Dommes Aurélie
email: dommes@inrets.fr

Cavallo Viola
email: cavallo@inrets.fr

THE BENEFICIAL EFFECTS OF A SIMULATOR-BASED TRAINING ON THE ELDERLY PEDESTRIAN SAFETY

Keywords: street-crossing, aging, training, simulator

International accident statistics indicate that elderly pedestrians make up an extremely vulnerable road-user group. Past research has shown that older adults have trouble taking the speed of approaching vehicles into account in deciding whether or not to cross the street: contrary to younger pedestrians, older adults make many unsafe decisions when vehicles are approaching at high speeds and miss safe opportunities to cross when vehicles approach slowly. Although for many seniors, walking is the major way of getting around, there are surprisingly no studies on improving the safety of elderly pedestrians through training. The present study was aimed at contributing to this issue. Our objective was to develop and assess the effectiveness of a training program that combined educational and behavioral interventions. To this end, 20 seniors were enrolled in a simulator-based streetcrossing training program and 20 other seniors were assigned to the control group (internet-use training). Before the training, immediately after it, and 6 months later, the street-crossing decisions of the 40 older participants were assessed using a simulated street-crossing task. Twenty younger participants performed the same task to serve as a baseline against which the performance of the older trained group was compared. The results showed that the training produced significant short-and long-term benefits and enhanced the overall safety of the experimental participants' street-crossing decisions. In view of applying our method, it would be important to separate the effects of educational training (explicit feedback; training instructions) and repeated practice in crossing the street on the simulator. A partial answer to this question can be found by looking at the results of the control group, whose performance improved with task repetition in such a way that on the long-term followup test, no significant difference was found between the two groups. More generally, these findings suggest that combining repeated simulator-based street-crossing practice with enhanced awareness (acquired explicitly or implicitly) of street-crossing dangers has a positive effect. When compared with the younger participants, the older participants of the experimental group considerably improved their behavior so that age-related differences in the mean safety-related indicators were no longer observed after training. However, the older participants' ability to take the oncoming car's speed into account in their decisions did not improve with training. This finding may reflect age-related sensory and cognitive difficulties that cannot be remedied by a behavioral or educational method. Further studies are therefore required to identify the sensory, perceptual, and cognitive abilities involved in street-crossing decisionmaking. A better understanding of these skills would be useful in designing future cognitive training programs likely to improve the behavior of senior pedestrians.

PURPOSE OF THE STUDY

International accident statistics indicate that elderly pedestrians make up an extremely vulnerable road-user group. In France, more than half of all pedestrians killed on the road (51%) are over 65 years old, whereas this age group represents less than 15% of the population [ONISIR, 2006]. In French urban areas, the percentage of elderly pedestrians killed on the road even reaches 63%. Developing countermeasures for improving the safety of street crossing among older adults is therefore becoming an urgent problem. Past research [START_REF] Lobjois | Age-related differences in street-crossing decisions: The effects of vehicle speed and time constraints on gap selection in an estimation task[END_REF], 2009;[START_REF] Oxley | Differences in traffic judgments between young and old adults pedestrians[END_REF][START_REF] Oxley | Crossing roads safely: an experimental study of age differences in gap selection by pedestrians[END_REF] has highlighted some of the age-specific characteristics of road-crossing behavior: slowing of decision-making, decreased walking speed, difficulty in selecting safe gaps and adopting sufficient safety margins. More specifically, these studies showed that older adults have trouble taking the speed of approaching cars into account in deciding whether to cross the street: contrary to younger adults, who accepted constant time gaps, older pedestrians were found to accept shorter and shorter time gaps as the car's speed increased, putting them at a higher risk at high speeds. They also tended to miss safe opportunities to cross in front of cars approaching at low speeds. These behaviors are thought to reflect age-related difficulties in processing information about the approaching car's speed and integrating it into the decisionmaking process. With aging, distance gap seems to become the overriding parameter for deciding whether or not to cross [START_REF] Lobjois | Age-related differences in street-crossing decisions: The effects of vehicle speed and time constraints on gap selection in an estimation task[END_REF]. Walking is essential to the mobility of elderly road users, not only for carrying out daily living tasks, but also for social insertion and physical exercise. Although the number of pedestrian zones continues to increase, and urban planning had been updated with pedestrians in mind, walkers in the city are still far from being perfectly safe. Surprisingly, there doesn't seem to be any research on behavior-based safety measures, i.e., training programs to teach older adults to adopt safer street-crossing behaviors. The present study was aimed at contributing to this issue. Our objective was to develop and assess the effectiveness of a training program that combined educational and behavioral interventions. To our knowledge, the only street-crossing training programs that have been developed were aimed at child pedestrians [e.g., [START_REF] Thomson | Influence of virtual reality training on the roadside crossing judgments of child pedestrians[END_REF] or brain damaged pedestrians [e.g., [START_REF] Weiss | Design and testing of a virtual environment to train stroke patients with unilateral spatial neglect to cross a street safely[END_REF], but not seniors pedestrians. And yet, data from laboratory studies clearly indicate that elderly adults can improve their performance with practice and training. A new research trend on retraining older adults in the perceptual, motor, and/or cognitive skills of daily activities emerged about twenty years ago and has been growing ever since [e.g., [START_REF] Edwards | The impact of speed of processing training on cognitive and everyday performance[END_REF]. In this line, some studies focused on older drivers and how they handle their difficulties [for a review see [START_REF] Korner-Bitensky | Older driver retraining: An updated systematic review of evidence of effectiveness[END_REF].

The training method we used specifically addresses rehabilitation of the behavioral component of street crossing by providing simulator-based training. Simulators and virtual reality have already proven to be powerful training devices to prevent child pedestrian injury [e.g., [START_REF] Schwebel | Validation of virtual reality as a tool to understand and prevent child pedestrian injury[END_REF], rehabilitate brain damage deficits [e.g., [START_REF] Akinwuntan | Effect of simulator training on driving after stroke: A randomized controlled trial[END_REF] or learn basic driving skills [e.g., [START_REF] Kappé | The use of driving simulators for initial driver training and testing[END_REF]. Some other advantages of simulators are that they provide feedback, allow for graduated levels of task difficulty, and make it possible to adapt the training to each individual's abilities, in such a way that effective and personalized skill learning or relearning can be achieved [START_REF] Weiss | Design and testing of a virtual environment to train stroke patients with unilateral spatial neglect to cross a street safely[END_REF].

The validity of the interactive street-crossing simulator we used in the present study has already been demonstrated [see [START_REF] Cavallo | The interest of an interactive road crossing simulation for the study of adaptive road crossing behavior[END_REF]. With a high level of immersion and presence sensation, it allows for safe street crossing as well as a perfect control over the characteristics of the traffic (i.e., in our case, vehicle speed and time gaps). The simulator-based training method we developed promoted not only individual sensory-motor practice, but also addressed elderly adults' ways of thinking about the task and the strategies they bring into play. Through explicit online and offline behavioral feedback (about safety margins and median accepted time gap, respectively), the training was aimed at modifying older adults' street-crossing strategies. More specifically, one of our objectives was to improve the way seniors process the speed information and use it in their decisions and behaviors. In particular, pedestrians were encouraged to assess the approaching car's speed before crossing rather than considering its distance only, even if this meant starting to cross later. They were also encouraged to observe the approaching traffic as they crossed and to increase their pace if the car was arriving faster than expected. In sum, by means of repeated practice and a better understanding of the task constraints, our training program was aimed at improving the overall safety of elderly adults when crossing the street, and also at helping them take the approaching car's speed into account in a safer way. In addition, by recruiting younger adults, we also examined to what extent age-related differences in street-crossing safety could be reduced after older pedestrians participated in the street-crossing training program. The 40 seniors were retired individuals living on their own. They all underwent a medical examination (which included sight and hearing acuity and current medication) to ensure study eligibility (i.e., absence of major cardiac, neurological, and visual disorders or diseases). All seniors obtained a score over 27 (M = 28.96, SD = 0.93) on the Mini-Mental State Examination [START_REF] Folstein | Mini-mental state. A practical method for grading the cognitive state of patients for the clinician[END_REF], which indicated that they were not affected by cognitive impairments. Twenty younger participants (10 women and 10 men) ranging in age from 20 to 30 (M = 25.15 years, SD = 3.28) were also recruited. They did not receive any training.

Experimental Setup

The street-crossing simulation device was based on the INRETS Sim 2 driving simulator [START_REF] Espié | Vehicle-driven simulator versus traffic-driven simulator: The INRETS approach[END_REF] and adapted to the street-crossing situation [START_REF] Cavallo | The interest of an interactive road crossing simulation for the study of adaptive road crossing behavior[END_REF]. The device included a portion of experimental road (4.2-m wide, materialized on the ground), an image-generation system, three-screen projection (2.70 x 1.90 m), a 3D sound-rendition system, and a recording system. The setup provided the participant with a horizontal visual field between 90° (at the starting point) and 140° (in the middle). The vertical visual field was 40°. The images (30 Hz refresh rate) were calculated and projected at the participant's eye height. Scenes were updated interactively by a movement-tracking system that recorded the participant's motion via a cable attached to her/his waist. The visual scene represented a one-way street 4.20 m wide sidewalk-to-sidewalk. Traffic consisted of a motorcycle followed by two identical cars moving at a constant speed from left to right (with respect to the participant standing on the sidewalk).

Street-Crossing Task

The 40 seniors and the 20 younger participants individually performed a simulated street-crossing task which served as pre-and post-tests. On each trial, participants were asked to stand at the edge of the sidewalk, facing the experimental road. They had to look left at the visual scene, paying attention to the approaching vehicles, and decide whether or not to cross between the two cars. If they thought there was not enough time, they were to remain on the sidewalk. If they thought it was safe to cross (without running), they had to walk (at any pace) over to the sidewalk on the other side of the street. The participant's crossing decisions and motion were recorded on each trial. Vehicle speed (30,40,50,60, and 70 km/hr) and time gap between the two cars (1 s to 7 s, in 1-s increments) were crossed. The number of repetitions per time gap differed according to their probability of being considered acceptable for crossing. In fact, it has been shown that the shortest gaps are always refused and the longest gaps always accepted [START_REF] Lobjois | Age-related differences in street-crossing decisions: The effects of vehicle speed and time constraints on gap selection in an estimation task[END_REF]. For this reason, the 1-and 7-s time gaps were presented once, the 2-and 6-s time gaps twice, and the 3-, 4-, and 5-s time gaps, three times. This combination of 15 trials and 5 speeds resulted in a total of 75 trials. The 75 trials were randomized and divided up into 2 blocks, with a break for the participants between the blocks. Before beginning the street-crossing task, the experimenter presented the basic principles of the study. Then the participants performed practice trials (vehicle speeds of 30, 50, and 70 km/hr and time gaps of 1, 4, and 7 s) until they fully understood the task. The complete test session lasted approximately 30-45 min. The younger participants group performed the task only once to assess their streetcrossing behaviors and serve as a baseline. The older participants groups performed the simulated street-crossing task three times, before they were trained, immediately after and 6 months later.

Older Training

Street-Crossing Training: The Older Experimental Group

The training program comprised two 1.5-hour sessions, which were separated by approximately one week. The first training session began with a discussion (approximately 30 min) about what information should be taken into account in order to cross the street safely and what safety-conscious behaviors should be adopted. The participant was then asked to do three street-crossing training modules. The presentation order of the three modules was counterbalanced over the two training sessions. The modules presented the same visual scene as the one used in the test session. The task was also identical. Vehicle speed (Module A: 30 vs 50 km/hr; Module B: 40 vs 60 km/hr; Module C: 50 vs 70 km/hr) and time gap (1 to 7 s) were varied, making for a total of 42 randomly presented trials per module. Each module was repeated immediately, so the participants did each module twice in a row. During and after each module, the experimenter gave the participant two kinds of feedback. The first concerned the safety margin, which was computed online for each trial. If the participant's safety margin was above 1.5 s [criterion set on the basis of [START_REF] Simpson | An investigation of road crossing in a virtual environment[END_REF], the crossing was scored as safe. The experimenter then initiated the next trial. If the safety margin was below 1.5 s, the experimenter informed the participant about its value. Then, they discussed about what made this behavior risky (time gap too short, initiation time too long, high speed of approaching car, etc.). When the experimenter felt the participant did not fully understand, the trial was repeated. The second kind of feedback pertained to the median accepted time gap. At the end of each training module, the experimenter and the participant looked together at the effect of the approaching car's speed on her/his median accepted time gap. For each trained speed, the participant's median accepted time gap was computed via a logistic function on the raw data [for more details see [START_REF] Lobjois | Age-related differences in street-crossing decisions: The effects of vehicle speed and time constraints on gap selection in an estimation task[END_REF]. If the participant's decisions exhibited a speed effect (i.e., the median accepted time gap decreased as speed increased), the experimenter stressed the importance of paying better attention to the speed of the approaching car before deciding whether or not to cross the street.

Internet-Use Training: The Older Control Group

Participants in the control group were given computer and internet-use training so that they could experience the same amount of social contact and have the same number of sessions as the experimental group. Participants received an introduction to the computer and instruction in how to use and access websites. They carried out information search exercises on topics that interested them (e.g., health, etc.).

RESULTS

For each accepted crossing, safety margin was calculated from the respective positions of i) the pedestrian on the experimental road and ii) the second car on the virtual road. Safety margin was the time between the moments when the participant reached the opposite sidewalk and when the front end of the second car reached the crossing line; safety margin was negative if the participant was still on the road when the front of the second car passed the crossing line. From the safety margins, two categories of decisions were defined: a crossing was scored as a safe decision when safety margin was greater than 1.5 s and the crossing was scored as an unsafe decision when safety margin was negative. These two variables were expressed as percentages of the total number of crossings accepted by the participant. Two types of analyses were performed. The first examined the short-and long-term effects of the street-crossing training program by comparing the performances of the experimental and control older groups. The second analysis examined age-related differences before and after street-crossing training by comparing the performances of the older experimental group with those obtained by the younger group.

Short-and Long-Term Effects of Street-Crossing Training

For each of the two variables (safe and unsafe decisions), an ANOVA was performed with group (experimental, control) as a between-participant factor, and with testing point (pre-test, immediate post-test, and 6-month post-test) and speed of the approaching car as within-participant factors. The significance level was set at .05. Partial η² was used as an index of the relative effect size. Significant effects were further examined using Tukey's post-hoc tests.

Safe decisions

The results yielded a significant group x testing point interaction F(2,76) = 10.9, p < .001, η² = .22. The post-hoc analyses indicated significant group differences on the immediate post-test only (p < .05), where the experimental group made more safe decisions than the control group. The experimental group exhibited a significant increase in the percentage of safe decisions between the pre-and the immediate post-tests (p < .001), which was maintained on the 6-month post-test (p < .001). The control group also exhibited a significant increase of safe decisions between the preand immediate post-tests (p < .001) that persisted on the 6-month post-test (p < .001). The results also yielded a significant effect of speed, F(4,152) = 440.1, p < .001, η² = .86, with safe decisions decreasing as speed increased.

Unsafe decisions

Given that there were no unsafe decisions when the vehicle was travelling at 30 km/hr, the ANOVA only pertained to speeds of 40, 50, 60, and 70 km/hr. The results yielded a significant group x testing point x speed interaction, F(6,228) = 2.9, p < .01, η² = .07 (see Figure 1). Post-hoc tests for the experimental group revealed a significant decrease in the mean percentage of unsafe decisions between the pretest and the immediate post-test (p < .05), which was maintained on the 6-month post-test (p < .05) when the vehicle was approaching at 50, 60, or 70 km/hr, whereas no significant differences appeared between the three testing points when the car was approaching at 40 km/hr. The control group also exhibited a significant decline in the mean percentage of unsafe decisions between the pre-test and the both posttests but only when the car was approaching at 70 km/hr (p < .001). The two groups did not differ significantly from each other on the immediate or 6-month post-test at any speed. However, while on the pre-test both groups made significantly more unsafe decisions at 70 than at 40 km/hr (p < .001), the speed effect was no longer observed in the experimental group on the immediate post-test. In contrast, the control group still made significantly more unsafe decisions at 70 than at 40 km/hr (p < .01). But, the reduction in the number of unsafe decisions at the high speed in the experimental group did not last: on the 6-month post-test, both groups made significantly more unsafe decisions at 70 km/hr than at 40 km/hr (p < .05).

Age-Related Differences Before and After Street-Crossing Training

For each of the two variables (safe and unsafe decisions), an ANOVA was performed with age (younger, older) as a between-participant factor, and with comparison point (before, immediately, and 6 months after older training) and speed of the approaching car as within-participant factors.

Safe decisions

The results yielded a significant age x comparison point interaction F(2,76)=49.1, p<.001, η² =.56. Post hoc tests showed that the two age groups differed significantly before older training (p<.05) with older participants making fewer safe decisions than the younger ones. Significant age-related differences were no longer observed immediately after (p>.09) and 6 months after older training (p>.70).

The results also yielded a significant age x comparison point x speed interaction F(8,304)=2.4, p<.05, η² =.06. Before training, older participants made less safe decisions than the younger ones when the car was approaching at high speeds (i.e., at 60 and 70 km/hr, see Figure 2, p<.05). Immediately and 6 months after older training, significant age-related differences were no longer observed at high speeds; age-related differences appeared only at low speed where older participants made significantly more safe decisions than the younger ones (i.e., at 30 km/hr, p<.05).

Unsafe decisions

The results indicated a significant age x comparison point interaction F(2,76)=34.9, p<.001, η² =.48. Post-hoc analyses showed significant age-related differences only before older training (p<.001) where the older participants made more unsafe decisions than the younger ones. Immediately and 6 months after older training, significant age-related differences were no longer observed (p>.60). The results also showed a significant age x comparison point x speed interaction F(8,304)=16.4, p<.001, η² =.30 (see Figure 3). While the younger participants showed no speed effect, the older participants made significantly more unsafe decisions as speed of the approaching car increased before they undertook the training program (p<.001 between each of the speeds excepts between 30 and 40 km/hr). They made more unsafe decisions than the younger participants when the car was approaching at high speeds (i.e., at 50, 60 and 70 km/hr, p<.001).

Immediately after training, the speed effect was no longer observed in the older participants' unsafe decisions, and no age-related differences appeared at any speed of the approaching car. However, 6 months after training, older participants' decisions showed again a speed effect: they made more unsafe decisions when the car was approaching at 70 km/hr than at 60, 50, 40 and 30 km/hr (p<.001). Whereas older participants made more unsafe decisions than the younger ones when the car was approaching at 70 km/hr (p<.01), no significant age-related differences were observed at 30, 40, 50 and 60 km/hr.

DISCUSSION

The participants who benefitted from the street-crossing training program exhibited a significant improvement in the safeness of their street-crossing decisions.

Immediately after the training, more safe and fewer unsafe decisions were observed. The benefits were still present six months after training. These results suggested that a combination of repeated practice and educational training can lead to safer streetcrossing decisions among elderly pedestrians. Two possible explanations can be formulated. The first is that participants may have taken advantage of the explicit and educational feedback given them during the training program, i.e., online safety margins and offline median accepted time gaps.

The second is that participants may have made better use of the implicit continuous visual feedback available in the interactive street-crossing task: the simulator provided a perception-action coupling that enabled participants to adapt their actions to their visual perceptions. Although a study by [START_REF] Lobjois | The effects of aging on street-crossing behavior: from estimation to actual crossing[END_REF] showed that elderly participants did not take advantage of the adjustment possibilities offered by the simulator, the results of the present study are compatible with the idea that the training program promoted better use of visual feedback. The fact of having attracted the participants' attention to the availability of this information may have helped them better adjust their actions to what they were perceiving and therefore make safer decisions as they repeated the task. In view of applying our method, it would be important to separate the effects of educational training (explicit feedback and instructions) and repeated practice in crossing the street on the simulator.

A partial answer to this question can be found by looking at the results of the control group, whose performance improved with task repetition. On the final post-test, no significant difference was found between the two older groups suggesting that the control group had progressed just about as much as the experimental group. The progress of the control group could be ascribed to enhanced awareness of streetcrossing dangers acquired implicitly over task repetition. Over time, they could also have benefitted from the perception-action coupling offered by the simulator. The progresses made by both older groups suggest that combining repeated simulator-based street-crossing practice with enhanced awareness (acquired explicitly or implicitly) of street-crossing dangers can have a positive effect. When compared with the younger participants, the older participants of the experimental group considerably improved their behavior so that age-related differences in the mean safety-related indicators were no longer observed after training. However, the older participants' ability to take the oncoming car's speed into account in their decisions did not improve with training. Contrary to the younger ones, older participants made more unsafe decisions when cars were approaching at high speeds than at low speeds. These age-related differences appeared before, as well as 6 months after training. This finding may reflect age-related sensory and cognitive difficulties that cannot be remedied by a simulator-based behavioral method.

CONCLUSION

The results of this study showed that training can improve the safety of elderly pedestrians and provided a basis for developing future programs adapted to their difficulties. The lack of effectiveness of our training program in the way older pedestrians used the approaching car's speed in their decisions may reveal agerelated sensory and cognitive difficulties that the simulator-based educational and behavioral method could not alleviate. Further studies are therefore required to identify the sensory, perceptual, and cognitive abilities involved in street-crossing decision-making. A better understanding of these skills would be useful in designing cognitive training programs likely to improve the behavior of senior pedestrians.

  Twenty elderly participants (11 women and 9 men) ranging in age from 65 to 83 (M = 73.05 years, SD = 4.44) were enrolled in the street-crossing training program. A control group of twenty elderly participants (12 women and 8 men) ranging in age from 61 to 82 (M = 71.35 years, SD = 5.78) was pre-and post-tested at the same time as were participants in the experimental group. Instead of the street-crossing training, the control group participants were given an internet-use training course.

Figure 1 .

 1 Figure 1. Mean percentage of unsafe decisions, by group, speed, and testing point.

Figure 2 .

 2 Figure 2. Mean percentage of safe decisions in function of age group, speed of the approaching car and comparison points.

Figure 3 .

 3 Figure 3. Mean percentage of unsafe decisions in function of age group, speed of the approaching car and comparison point.


J Vidal

P Tjørnelund

P Knoblauch

R Buhl-Jensen

R Molife

J S Brown

T R J De Bono

Evans

Dr N L Steele

J A Plumb

L Vidal

J Tjørnelund

P Buhl-Jensen

R Brown

J S De Bono

T R J Evans

Pharmacokinetic and pharmacodynamic properties of an oral formulation of the histone deacetylase inhibitor Belinostat (PXD101

Keywords: Histone deacetylase, Phase 1 trial, Pharmacokinetics, Pharmacodynamics, bioavailability

Pharmacokinetic and pharmacodynamic properties of an oral formulation of the histone deacetylase inhibitor Belinostat (PXD101)

Patients and Methods

Oral belinostat was administered in a range of doses and schedules (once, twice, or thrice daily), on either day 1 or days 1 -5, of the second or a subsequent treatment cycle in 15 patients who were included in the phase I trial of intravenous belinostat.

Serial blood samples were collected for pharmacokinetic and pharmacodynamic (histone acetylation) analyses, and the results compared with corresponding analyses following intravenous administration.

Results

A total mean daily AUC of 2767 1453 ng hr/ml (8.7 4.6 M hr) resulted from a dose of 1000 mg/m 2 once daily (qd). There was no clear evidence of drug accumulation on twice daily dosing (bid) however a trend towards accumulation was apparent when belinostat was given three times daily (tid). Mean half life (T½) of a single dose of 1000 mg/m 2 was 1.5 hr ( 0.3 hr) and peak levels were reached in an average of 1.9hrs ( 0.3 hr). The half life was found to be independent of dose, but a trend towards increasing half life following multiple dosing was observed. Histone H4

INTRODUCTION

Deregulation of the balance between histone acetylation and deacetylation plays a role in the generation and suppression of neoplasia. The histone deacetylase (HDAC) enzymes catalyse the removal of an acetyl group from the terminal lysine residues of histone proteins, leading to more compact chromatin and repression of associated genes. Inhibitors of HDAC enzymes alter patterns of gene expression, induce cellular differentiation and promote cell cycle arrest and apoptosis [START_REF] Marks | Histone deacetylase inhibitors: inducers of differentiation or apoptosis of transformed cells[END_REF]. Pharmacologic inhibition of histone deacetylation may therefore regulate gene expression patterns and, subsequently, cellular characteristics, making them attractive anti-cancer therapies. Histone deacetylase inhibitors (HDACi) are relatively selective for cancer cells, possibly due to their effects being limited to only a small number of genes [START_REF] Van Lint | The expression of a small fraction of cellular genes is changed in response to histone hyperacetylation[END_REF].

In addition, acetylation of non-histone proteins e.g. p53 [START_REF] Gu | Activation of p53 sequence-specific DNA binding by acetylation of the p53 C-terminal domain[END_REF] and Rb [START_REF] Chan | Acetylation control of the retinoblastoma tumour-suppressor protein[END_REF] may play a role in the anti-tumour activity of these compounds.

Belinostat (PXD101) is a novel hydroxamic acid HDAC inhibitor with potent antiproliferative and HDAC inhibitory activity both in vitro and in vivo [START_REF] Plumb | Pharmacodynamic response and inhibition of growth of human tumor xenografts by the novel histone deacetylase inhibitor PXD101[END_REF]. Inhibition of tumour growth by belinostat is associated with a marked increase in the level of acetylation of histone proteins [START_REF] Plumb | Pharmacodynamic response and inhibition of growth of human tumor xenografts by the novel histone deacetylase inhibitor PXD101[END_REF]. We have previously reported the results of a phase I trial of belinostat administered as a 30-minute intravenous infusion on days 1-5 of a 21-day cycle [START_REF] Steele | A phase 1 pharmacokinetic and pharmacodynamic study of the histone deacetylase inhibitor belinostat in patients with advanced solid tumors[END_REF]. In this trial, belinostat was well-tolerated, exhibited dose-dependent pharmacodynamic (PD) effects, and had promising anti-tumour activity. The maximum tolerated dose of belinostat administered intravenously in this dose and schedule was 1000mg/m 2 /day [START_REF] Steele | A phase 1 pharmacokinetic and pharmacodynamic study of the histone deacetylase inhibitor belinostat in patients with advanced solid tumors[END_REF].

However, pharmacodynamic effects of belinostat on histone acetylation were most marked in the first few hours following intravenous drug administration.

Consequently, a protracted or continuous daily oral dosing schedule could be advantageous, allowing continual target inhibition. In addition, patient convenience and health economic benefits also favour an oral route of administration. Furthermore, the availability of both intravenous and oral routes of administration would allow greater flexibility to design combination regimens with other anti-cancer agents in subsequent clinical studies.

The primary objective of this sub-study, undertaken as an extension to the previously reported phase I study, was to explore the feasibility, tolerability and pharmacokinetics (PK) of belinostat when administered by the oral route. Preliminary PD studies were also performed to enable comparison of the biologic effects of the oral and intravenous formulations.

PATIENTS AND METHODS

Patient Eligibility

This study was conducted as an extension to the phase 1 trial of intravenous belinostat which has previously been reported [START_REF] Steele | A phase 1 pharmacokinetic and pharmacodynamic study of the histone deacetylase inhibitor belinostat in patients with advanced solid tumors[END_REF]. Eligible patients were those with histologic or cytologic confirmed advanced malignancy, refractory to standard therapy, or for whom no standard therapy existed. Other inclusion criteria included age ≥ 18 years, ECOG performance status (PS) ≤ 2 and estimated life expectancy of ≥ 3 months.

Adequate bone marrow, hepatic and renal function for trial entry was defined as: Hb ≥ 9.0g/dl, absolute neutrophil count ≥ 1.5 x 10 9 /l, platelets ≥ 100 x 10 9 /l, total bilirubin ≤ 1.5 x upper limit of normal (ULN), AST and ALT ≤ 2.5 x ULN (or ≤ 5 x ULN if liver metastases were present), serum creatinine ≤ 1.5 x ULN. Female patients of reproductive potential were required to have a negative pregnancy test.

Patients were excluded from the trial if they had received any anti-cancer therapy within the preceding 4 weeks. Continuation of bisphosphonates, LHRH agonists or corticosteroids was permitted provided dosing was stable before and during the trial.

Other exclusions were co-existing illness likely to interfere with trial procedures, uncontrolled brain metastases, persistent neuropathy ≥ NCI-CTCAE grade 2 of any cause, pregnant or lactating women, and known HIV infection.

Amendments to the original trial protocol of intravenous belinostat, to allow oral administration using a variety of schedules, were approved by the Research Ethics Committees at both participating institutions. Specific written informed consent for the oral sub-study was obtained from each patient in addition to the consent previously obtained for the main trial of intravenous belinostat.

Study Design

All patients received belinostat as a 30-minute intravenous infusion daily on days 1-5 of a 21-day cycle. The starting dose was 150 mg/m 2 . Sequential cohorts of 3-6 patients were entered into one of the escalating dose levels. Dose escalation was in 100% increments until grade 2 toxicity was observed, at which point dose escalation was in 50% increments until grade 3 toxicity was seen, following which further dose increments would be of 33%.

Following the initiation of the phase I trial of intravenous belinostat, a limited preliminary study of oral drug administration was planned in patients already enrolled to the main trial. On the basis that pre-clinical data from dogs had demonstrated an oral bioavailability for belinostat of 30-35% (Topotarget, personal communication), eligible patients with stable disease after 2 cycles of intravenous belinostat were given a single oral dose of belinostat on day 1 of cycle 3. The dose administered was equal to the dose that had been tolerated when administered intravenously to the same patient. Following the single oral dose, all subsequent doses for this, and subsequent, cycles were administered intravenously. Following further amendments to the trial protocol belinostat was subsequently administered orally, at the same dose as administered intravenously, twice or three times daily to eligible patients on day 1 only of their second, or subsequent, cycle and then administered, again at the same dose as administered intravenously, in a further cohort of patients once daily on days 1-5 of the second or third cycle. All other doses in all subsequent cycles were administered intravenously.

Toxicities were assessed weekly and graded and reported according to NCI-CTCAE v3.0. Patient assessments for toxicity and anti-tumour activity were not influenced by participation in this sub-study of oral administration of belinostat. Dose limiting toxicity (DLT) was based on the toxicities observed in the first 21 day cycle of intravenous belinostat. However, patients participating in the oral dosing sub-study were observed for any toxicity in addition to those seen with intravenous treatment.

Drug Preparation and Administration

Belinostat was supplied by Topotarget, Copenhagen, Denmark. Belinostat powder was formulated in standard gelatine capsules containing 250 mg for oral administration. Patients were not required to fast prior to drug administration.

Pharmacokinetic studies

PK samples were taken from 14 of the 15 patients enrolled in the oral study. Samples of 5 mL of blood were collected at the following time-points: once daily dosing schedule -time 0 (before oral administration of belinostat) then at 5, 15, 30, 60 and 90 minutes and 2, 4, 6, 8, 10 and 24 hours after administration; twice daily dosing schedule -time 0, then at 15, 30, 60 and 90 minutes and 2, 4, 6, 8 and 12 hours (immediately before the second oral dose) after administration, and at 2, 4, 6, 8 and 12 hours (prior to the next intravenous dose) after administration of the second oral dose; thrice daily dosing schedule -time 0, then at 15, 30, 60 and 90 minutes and 2, 4, 6 and 8 hours (immediately before the second dose) following the first dose, at 2, 4, 6 and 8 hours (prior to the third dose) following the second dose, and then at 8 hours (prior to the next intravenous dose) following the third dose.

Lithium heparinised blood samples were placed on ice then centrifuged at 4°C. Two milliliter aliquots of plasma were stored at -70°C until analysis. The concentration of belinostat in plasma was analysed by liquid chromatography with tandem mass spectrometry detection as previously described [START_REF] Steele | A phase 1 pharmacokinetic and pharmacodynamic study of the histone deacetylase inhibitor belinostat in patients with advanced solid tumors[END_REF]. PK calculations were performed using a non-compartmental method (WinNonLin version 5.1.0, model 200). The area under the plasma concentration time curve (AUC) was calculated using the linear trapezoid method and uniform weighting, and the elimination half-life was calculated by the log-linear method.

Pharmacodynamic Studies

Histone hyperacetylation in peripheral blood mononuclear cells

Histone acetylation was evaluated by Western blotting for histone H4 on histones isolated from peripheral blood mononuclear cells (PBMCs). Samples for histone acetylation were taken at various time points after intravenous administration of belinostat in cycle 1 and after oral administration in cycle 2. Blood samples (6 ml) were collected in lithium heparin vacutainer tubes, placed on ice and processed immediately using a modification of the method described by Yoshida et al [START_REF] Yoshida | Potent and specific inhibition of mammalian histone deacetylase both in vivo and in vitro by trichostatin A[END_REF] and as previously described [START_REF] Steele | A phase 1 pharmacokinetic and pharmacodynamic study of the histone deacetylase inhibitor belinostat in patients with advanced solid tumors[END_REF]. Densitometry was carried out on the resulting Western blots and the results were expressed relative to a control sample (histones extracted from A2780 ovarian cancer cell line treated for 1 hour with belinostat 0.2µM). The same cell line standard was used in all blots. AUC for histone acetylation was calculated by non-compartmental analysis using WinNonLin Version 4.0 software (Pharsight, Mountain View, USA).

RESULTS

Patient Characteristics

A total of 46 patients were recruited into the phase 1 trial of belinostat, by intravenous administration, between October 2003 and February 2006 as previously reported [START_REF] Steele | A phase 1 pharmacokinetic and pharmacodynamic study of the histone deacetylase inhibitor belinostat in patients with advanced solid tumors[END_REF].

Fifteen of these patients were also enrolled into this sub-study of oral belinostat between August 2004 and January 2006. Details of the oral dosing schedule for each patient are summarised in table 1. One patient received two schedules of oral belinostat in different treatment cycles. Baseline characteristics for these 15 patients are summarised in table 2.

Toxicity Assessments

There were no toxicities, in addition to those observed with the intravenous formulation, in any of the 15 patients who were treated in this sub-study with oral belinostat. The most frequent toxicities associated with the brief duration of the oral dosing schedules were nausea (2 patients), vomiting (2 patients), fatigue (2 patients) and decreased lymphocyte counts (3 patients). These were all mild and self-limiting.

Nausea and vomiting tended to occur several hours after oral dosing compared with the intravenous administration treatment schedule in which nausea and vomiting tended to occur at the end of the 30-minute intravenous infusion.

Pharmacokinetics

The pharmacokinetic profile of oral belinostat was evaluated in 14 patients using a variety of dosing schedules and compared with the pharmacokinetic profile of belinostat by intravenous administration in the same patients. These results are summarised in table 3. The exposure following oral dosing of belinostat was variable but sufficient to achieve histone acetylation (Figure 2) and in a potentially therapeutic range based on observations in pre-clinical models [START_REF] Tumber | The histone deacetylase inhibitor PXD101 synergises with 5-Fluorouracil to inhibit colon cancer cell growth in vitro and in vivo[END_REF][START_REF] Qian | Activity of PXD101, a histone deacetylase inhibitor, in preclinical ovarian cancer studies[END_REF][START_REF] Qian | Activity of the histone deacetylase inhibitor belinostat (PXD101) in preclinical models of prostate cancer[END_REF]. Total mean daily AUC of 2767 1453 ng hr/ml (8.7 4.6 M hr) resulted from a dose of 1000 mg/m 2 once daily (qd). There was no clear evidence of drug accumulation on twice daily dosing (bid) however a trend towards accumulation was apparent when belinostat was given three times daily (tid). Mean half life (T½) of a single dose of 1000 mg/m 2 was 1.5 hr ( 0.3 hr) and peak levels were reached in an average of 1.9hrs ( 0.3 hr). The half life was found to be independent of dose, but a trend towards increasing half life following multiple dosing was observed. Assessment of dose linearity was not performed due to the small number of patients in this sub-study combined with the large variation in clearance.

Pharmacodynamic Studies Histone H4 hyperacetylation in peripheral blood mononuclear cells

Histone H4 acetylation levels following intravenous and oral administration of belinostat are shown in Figure 1. The pre-treatment level of histone acetylation was slightly higher in the group given oral belinostat. Histone acetylation increases rapidly after intravenous administration of belinostat (Tmax 77.1 ± 20.3). The rate of increase is slower following oral administration (Tmax 210.0 min ± 46.8) although increased levels are sustained for longer. For two patients samples were collected at 12 hours, immediately before a second oral dose was administered. At 12 hours the level of acetylation was above the baseline level and histone acetylation increased rapidly after the second oral dose. The AUC for histone acetylation measured over the first 6 hours is 272.2 ± 14.9 for intravenous and 276.6 ± 16.0 for oral administration (n=7).

Clinical Outcomes

Objective response and survival for patients treated with intravenous belinostat have previously been reported [START_REF] Steele | A phase 1 pharmacokinetic and pharmacodynamic study of the histone deacetylase inhibitor belinostat in patients with advanced solid tumors[END_REF]. It was not anticipated that these would have been influenced by oral dosing as each patient only had limited exposure to the oral formulation. Consequently there is no efficacy data from this preliminary sub-study.

DISCUSSION

The preliminary data reported in this study are limited by the small sample size and the heterogenous dosing cohorts, particularly with the thrice daily schedule which was only administered to two patients. Nevertheless, these preliminary data provide support for the continued development of an oral formulation of the HDAC inhibitor belinostat. Oral belinostat was well tolerated at high doses and provides higher exposure (AUC) in plasma than other orally dosed HDAC inhibitors such as MS-275, vorinostat and MGCD0103 at their recommended doses or at their respective maximum tolerated doses [START_REF] Siu | Phase I study of MGCD0103 given as a three-times-per-week oral dose in patients with advanced solid tumors[END_REF][START_REF] Ryan | Phase I and pharmacokinetic study of MS-275, a histone deacetylase inhibitor, in patients with advanced and refractory solid tumors or lymphoma[END_REF][START_REF] Kelly | Phase I study of an oral histone deacetylase inhibitor, suberoylanilide hydroxamic acid, in patients with advanced cancer[END_REF]. A slight increase in the AUC of belinostat from day 1 to day 5 was observed (qd = 26%; bid = 17%), although it is unclear if this observation is due to drug accumulation. No significant accumulation was found following intravenous infusion of belinostat for 5 consecutive days [START_REF] Steele | A phase 1 pharmacokinetic and pharmacodynamic study of the histone deacetylase inhibitor belinostat in patients with advanced solid tumors[END_REF]. Intake of food or fluid with the oral formulation was not controlled in this small study, and no preclinical food effect studies have been performed. Consequently, an effect of food on drug pharmacokinetics may have contributed to the variable and, in some cases, increased exposure similar to that reported for vorinostat [START_REF] Rubin | A study to determine the effects of food and multiple dosing on the pharmacokinetics of vorinostat given orally to patients with advanced cancer[END_REF] and MGD0103 [START_REF] Siu | Phase I study of MGCD0103 given as a three-times-per-week oral dose in patients with advanced solid tumors[END_REF].

The variability in clearance with oral belinostat is rather large. The coefficient of variation (CV) for the clearance has been calculated for dose groups with more than two patients. CV is 62% (n = 11) for the 1000 mg/m 2 dose level (qd and bid cohorts) whereas CVs are 39% (n = 4), 45% (n = 5), and 71% (n = 3) for the 1500, 1750, and 2000 mg groups, respectively. This indicates that dosing by body surface area does not eliminate variance in clearance for belinostat, similar to reported findings for MS-275 [START_REF] Acharya | Factors affecting the pharmacokinetic profile of MS-275, a novel histone deacetylase inhibitor, in patients with cancer[END_REF]. The reason for the variation in clearance has not been identified in this small study but correction for the patients' surface area may not be required for oral dosing of belinostat

The mean apparent half-life (t½) of 1.9 hours following oral administration of 1000 mg/m 2 on day 1 and 1.7 hours on day 5 were longer than the mean apparent t½ of 0.8 hours following intravenous administration of the oral-equivalent dose of belinostat.

This suggests an absorption-rate limited drug disposition in the GI tract and possibly entero-hepatic re-circulation. This observation is supported by pre-clinical studies with radiolabelled belinostat in the rat. In the intact rat, 45% of an oral dose is excreted via urine compared to 20% in bile ductcannulated rats. Influence of feeding conditions on absorption have been reported for other hydroxamate HDAC inhibitors including vorinostat [START_REF] Kelly | Phase I study of an oral histone deacetylase inhibitor, suberoylanilide hydroxamic acid, in patients with advanced cancer[END_REF] and MS-275 [START_REF] Siu | Phase I study of MGCD0103 given as a three-times-per-week oral dose in patients with advanced solid tumors[END_REF] The effects of belinostat on histone acetylation were comparable for the two routes of administration suggesting that oral dosing is an effective route of administration (Figure 1). Levels of acetylation increase more rapidly after intravenous than after oral administration which is consistent with the drug pharmacokinetics where the Tmax is later following oral drug administration. The level of acetylation was very low in untreated patients but was higher in the pre-treatment sample taken from patients prior to oral dosing. This could be explained by the effects of previous cycles of treatment. For two patients, levels of histone H4 acetylation were measured following the second oral dose (Figure 2). Acetylation levels increased rapidly as seen after the first dose indicating that twice daily dosing has a more prolonged effect on the drug target. tolerated in this small study. Preliminary indications of anti-tumour activity observed in the phase 1 trial of intravenous belinostat are encouraging and support further trials of this drug. An oral formulation could lead to enhanced drug exposure and, more importantly, prolonged effects on the intended drug target. A trial is ongoing to establish the optimal dose and schedule of oral administration of belinostat.

Fig 1

 1 Fig 1 Upper Figure: Plasma concentrations following intravenous administration of

Fig 2

 2 Fig 2 Plasma concentrations (open symbols) and histone H4 acetylation levels

Table 2 . Patient Characteristics

 2

	Characteristic	No. of patients
	Total	15
	Age (years)
	Median	57
	Range	25-70
	Sex
	Male	8
	Female	7
	ECOG Performance Status
	0	6
	1	9
	Tumour Type
	Colorectal	3
	Melanoma	1
	Renal	2
	Oesophago-gastric	1
	Sarcoma	3
	Ovary	1
	Thymoma	1
	Breast	1
	Prostate cancer	1
	NSCLC	1

Table 3 .

 3 Summary of Mean (±SD) PK Parameters after Oral Administration of belinostat *Data not sufficient for calculation of T½, AUC0-, Vz and Cl for one pt

	Administration Schedule (number of pt)	Dose (mg/m2)	Dose (mg)	Cmax (ng/mL)	Tmax (h)	T½ (h)	Vz (L)	CL (L/hr)	AUC 0-t (ng*hr/mL)	AUC 0-∞ (ng*hr/mL)	AUC 0-t/ AUC 0-∞
	Single day, qd n=2	900	1375 (±177)	3229 (±1376)	1.7 (±0.2)	0.9 (±0.2)	293 (±50)	219 (±1)	6266 (±862)	6292 (±862)	1.00
	Five days, qd Day 1 n=3	1000	1750 (±250)	681 (±350)	1.9 (±0.3)	1.5 (±0.3)	1511 (±592)	767 (±441)	2695 (±1461)	2767 (±1453)	0.97
	Five days, qd Day 5 n=3	1000	1750 (±250)	1317 (±736)	2.0 (±0.1)	1.7 (±1.1)	1416 (±1213)	516 (±134)	3016 (±573)	3476 (±648)	0.87
	Single day, qd n=1	1200	2500	1729	1.3	1.4	719	348	7139	7174	1.00
	Single day, bid, am n=7	1000	1750 (±189) 1447 (±782)	2.1 (±1.3)	1.6 (±0.4)	1104 (±691)	492 (±308)	4187 (±1552)	4357 (±1636)	0.96
	Single day, bid, pm* n=6	1000	1792 (±188)	817 (±299)	1.5 (±0.9)	2.6 (±1.6)	1356 (±736)	374 (±65) 4011 (±1278)	4706 (±711)	0.85
	Five days, bid am*(n=3)	1000	1917 (±144) 1054 (±663)	1.2 (±0.6)	3.4 (0.4)	2053 (±1180)	410 (±198)	3990 (±2270)	5116 (±2732)	0.78
	Single day, tid n=2 1 st dose*	1000	1875 (±177) 1227 (±780)	1.0 (±0.1)	2.0	1077	369	3688 (±1082)	4748	0.78
	Single day, tid n=2 2 nd dose	1000	1875 (±177)	1103 (±74)	3.1 (±1.5)	2.6 (± 0.8)	1515 (±979)	378 (±138)	4557 (± 1642)	5219 (±1432)	0.87
	Single day, tid n=2 3 rd dose	1000	1875 (±177)	974 (±485)	2.1 ±(0.0)	3.0 (±0.6)	1640 (±782)	370 (±104)	4327 (±1876)	5360 (±1984)	0.81

ACKNOWLEDGEMENTS

This study was supported by Topotarget, Copenhagen, Denmark. The investigators at both the study centres are supported by Cancer Research UK.

The investigators are grateful to the research teams at both study centres for their support of this study, and to the patients who agreed to participate in this study.


Sanjeev K Srivastava

Péter Antal

János Gál

Gábor Hullám

Ágnes F Semsei

György Nagy

Edit I András Falus

Buzás

Edit I Buzás
email: edit.buzas@gmail.com

Lack of evidence for association of two functional SNPs of CHI3L1 gene

à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Introduction

Rheumatoid arthritis (RA) is a common systemic inflammatory disease affecting approximately 1% of the adult population worldwide [START_REF] Lee | Rheumatoid arthritis[END_REF]. The disease is characterized by inflammation of synovial tissue, progressive cartilage destruction and bone erosion of affected joints. [START_REF] Lorentzen | Association of arthritis with a gene complex encoding C-type lectin-like receptors[END_REF] Despite of significant gains in knowledge of the immunopathology of RA, the exact etiology of the disease remains uncertain [START_REF] Lee | Rheumatoid arthritis[END_REF]. The genetic basis for RA is rather complex with a poorly understood cause. Several studies suggest roles of HLA-DRB1 [START_REF] Newton | A review of the MHC genetics of rheumatoid arthritis[END_REF] and PTPN22 [START_REF] Begovich | A missense single-nucleotide polymorphism in a gene encoding a protein tyrosine phosphatase (PTPN22) is associated with rheumatoid arthritis[END_REF][START_REF] Orozco | Association of a functional single-nucleotide polymorphism of PTPN22, encoding lymphoid protein phosphatase, with rheumatoid arthritis and systemic lupus erythematosus[END_REF][START_REF] Lee | The PTPN22 C1858T functional polymorphism and autoimmune diseases-a meta-analysis[END_REF] in RA pathogenesis. Three further RA risk loci have been identified recently, including the STAT4 gene [START_REF] Remmers | STAT4 and the risk of rheumatoid arthritis and systemic lupus erythematosus[END_REF][START_REF] Lee | Association of STAT4 with rheumatoid arthritis in the Korean population[END_REF][START_REF] Orozco | Association of STAT4 gene with rheumatoid arthritis: a replication study in three European populations[END_REF], loci in the 6q23 [START_REF] Thomson | Rheumatoid arthritis association at 6q23[END_REF][START_REF] Plenge | Two independent alleles at 6q23 associated with risk of rheumatoid arthritis[END_REF] and TRAF1/C5 [12][START_REF] Kurreeman | A candidate gene approach identifies the TRAF1/C5 region as a risk factor for rheumatoid arthritis[END_REF]. As RA is a major cause of disability and is even correlated with increased mortality in severe cases [START_REF] Kroot | No increased mortality in patients with rheumatoid arthritis: up to 10 years of follow up from disease onset[END_REF]. Identification of genetic risk factors of RA may help to understand basic mechanisms of autoimmunity and may be helpful in the development of targeted diagnostics and therapeutics.

Chitinase-3-like1 (CHI3L1) is a glycoprotein also known as human cartilage glycoprotein-39 (HC gp-39) or YKL-40. It has also been suggested to be a growth factor for connective tissue cells as well as a migration-promoting factor for endothelial cells [START_REF] Yamada | Failure to confirm genetic association of the CHI3L1 gene with schizophrenia in Japanese and Chinese populations[END_REF].

It is has been first described as a major secretory product of rheumatoid synovial fibroblasts by Nyirkos et al. [START_REF] Nyirkos | Human synovial cells secrete a 39 kDa protein similar to a bovine mammary protein expressed during the non-lactating period[END_REF]. Later it was demonstrated to be produced by articular chondrocytes and macrophages [START_REF] Hakala | Human cartilage gp-39, a major secretory product of articular chondrocytes and synovial fluid cells, is a mammalian member of a chitinase protein family[END_REF].

Its expression is under control of NF-kB [START_REF] Recklies | Inflammatory cytokines induce production of CHI3L1 by articular chondrocytes[END_REF] . CHI3L1 mRNA was shown to be expressed in diseased human osteoarthritic cartilage and osteophyte, while it was not detected in healthy adult cartilage [START_REF] Connor | Human cartilage glycoprotein 39 (HC gp-39) mRNA expression in adult and fetal chondrocytes, osteoblasts and osteocytes by in-situ hybridization[END_REF]. Peptides derived from HC gp-39 can bind to RA-associated DR4 (DRB1*0401) molecules and are recognized by peripheral blood T cells from patients with RA [START_REF] Verheijden | Human cartilage glycoprotein-39 as a candidate autoantigen in rheumatoid arthritis[END_REF].

Furthermore, elevated levels of CHI3L1 are reported to be associated with inflammatory disorders, such as RA [21][22][START_REF] Johansen | Serum YKL-40 levels in healthy children and adults. Comparison with serum and synovial fluid levels of YKL-40 in patients with osteoarthritis or trauma of the knee joint[END_REF].

Recently, functional variants of the promoter region CHI3L1 (including rs4950928) have been shown to be associated with susceptibility to schizophrenia [START_REF] Zhao | Functional variants in the promoter region of Chitinase 3-like 1 (CHI3L1) and susceptibility to schizophrenia[END_REF]. Also, a CHI3L1 gene polymorphism (rs10399931) has been reported to contribute to inter-individual variations of the CHI3L1 levels in sarcoidosis [START_REF] Kruit | A CHI3L1 gene polymorphism is associated with serum levels of YKL-40, a novel sarcoidosis marker[END_REF].

Given the known elevated levels of CHI3L1 in various inflammatory diseases reported by numerous groups [21][22][START_REF] Johansen | Serum YKL-40 levels in healthy children and adults. Comparison with serum and synovial fluid levels of YKL-40 in patients with osteoarthritis or trauma of the knee joint[END_REF], in this study we made an attempt to identify a possible disease association of functional single nucleotide polymorphisms (SNPs) of CHI3L1 in a Hungarian cohort of patients with RA and healthy controls.

Materials and methods

Subjects

We examined 182 patients suffering from RA (156 females, 26 males, mean age 61,98±10,51, range 32-85), treated in the Department of Rheumatology, County Hospital Kecskemét, Hungary.

Control subjects (94 males and 100 females; aged 36.8±10.5 years) with no known history of inflammatory arthritis were randomly selected from healthy blood donors (n=192) of the same ethnicity and from the same geographical region as the patients. All study subjects belonged to the Hungarian (Caucasian)

population, and all RA patients had the typical symptoms and diagnosis of RA. All RA patients met the American College of Rheumatology criteria for rheumatoid arthritis [START_REF] Arnett | The American Rheumatism Association 1987 revised criteria for the classification of rheumatoid arthritis[END_REF].

During the entire investigation period the guidelines and regulations approved by the local Ethical Committee and the Helsinki Declaration in 1975 were followed; the patients gave their informed consent for use of their anonymized DNA samples for research purposes.

Genotyping

Genomic DNA was extracted from EDTA anticoagulated whole blood-derived buffy coats, after sedimentation at room temperature. A commercial kit QIAamp® DNA blood mini kit (QIAGEN Inc, Chatsworth, CA, USA) was used following the instructions of the manufacturer.

Biallelic SNP genotyping was performed with TaqMan allelic discrimination assays (Applied Biosystems)

according to the recommendations of the manufacturer. PCR was performed using an ABI 7000 thermocycler, and fluorescent signals were analyzed using an ABI 7000 sequence detector single point measurement and SDS v2.3 software (Applied Biosystems).

The following assays were used for allelic discrimination in the study:

CHI3L1-1 (rs10399931) and CHI3L1-2 (rs4950928). PCR was performed with components including12,5

μl Mastermix, 9.2 μl distilled water, 2 μl DNA (10 ng/ μl), 1.3 μl of primers and probes. The total reaction mixture was thus, 25 μl /well. The following cycle was repeated 45 times: 50 0 C -2 min, 95 0 C -10 min, 95 0 C -15 sec, 60 0 C -1 min.

Clinical and laboratory parameters

Gender, age of onset of the disease, levels of C-reactive protein (CRP), seropositivities for rheumatoid factor (RF) and anti-CCP antibodies, and the current disease activity scores (DAS28) of the patients were documented for all patients with RA. Controls did not suffer from any known joint diseases.

Statistical analysis

Genotypes were determined for all samples, and each SNP was assessed for deviation from Hardy-Weinberg equilibrium. Both allelic and genotypic association tests and Cochran-Armitage tests were performed using an online HWE calculator (http://ihg2.helmholtz-muenchen.de/cgi-bin/hw/hwa1.pl) [START_REF] Wigginton | A note on exact tests of Hardy-Weinberg equilibrium[END_REF].

Associations with susceptibility to RA were tested by calculating odds ration (OR) and 95% confidence interval (CI).

Results

We tested the possible association of two functional SNPs of the CHI3L1 gene with RA in a Hungarian cohort of patients by using allelic discrimination system. The baseline characteristics of the patients are summarized in Table 1.

Genotype frequencies were determined for both tested SNPs. Allele and genotype frequencies of the SNPs were calculated and are shown in Table 2. No deviation from the Hardy-Weinberg equilibrium (HWE) was observed either in RA patients or in controls. A comparison of allele and genotype frequencies of the polymorphism under study revealed no statistically significant differences between RA patients and healthy controls (Table 3).

After adjusting for age and gender using logistic regression, there was no significant association between the SNP-s and RA (we tested also their interaction) (data not shown).

Discussion

6

RA is a systemic autoimmune disease with complex genetic background, and dissecting its genetic components may shed light on important mechanism underlying the development of autoimmunity in susceptible individuals.

Several studies examined the role of CHI3L1 and reported to be associated with inflammatory disorders, such as RA [21][22][START_REF] Johansen | Serum YKL-40 levels in healthy children and adults. Comparison with serum and synovial fluid levels of YKL-40 in patients with osteoarthritis or trauma of the knee joint[END_REF]. Recently, the promoter SNP of the CHI3L1 gene (rs4950928) was found to be associated with elevated serum CHI3L1 levels as well in asthma, bronchial hyperresponsiveness, and measures of pulmonary functions [START_REF] Ober | Effect of variation in CHI3L1 on serum YKL-40 level, risk of asthma, and lung function[END_REF]. The same polymorphism was also demonstrated to be associated with schizophrenia [START_REF] Wigginton | A note on exact tests of Hardy-Weinberg equilibrium[END_REF].

The elevated levels and suggested role of CHI3L1 in the regulation of cytokine signaling as well as its protective role in inflammatory environments [START_REF] Ling | The chitinase 3-like protein human cartilage glycoprotein 39 inhibits cellular responses to the inflammatory cytokines interleukin-1 and tumour necrosis factor-alpha[END_REF] were compelling to hypothesize that functional polymorphisms of the CHI3L1gene might be associated with RA.

Surprisingly, there were no significant differences in the distributions of alleles and genotypes between the RA patients and controls. Haplotype analysis of these two polymorphisms did not show differences between the two groups either.

We also carried out power analysis in order to refine our conclusions. Assuming a dominant model, the sample size in the study (377), and a significance level 0.05, we investigated the power for the estimated allele frequency range (22%-29.5%) and the estimated OR range (<4). We found that the power diminished below OR=2, thus, based on our data, we can not exclude associations with RA below this level.

Our present data argue that the reported elevated CHI3L1 levels in RA might be consequences rather than causative components of the inflammatory processes in RA. However, further SNPs of the CHI3L1 gene need to be tested in order to entirely rule out the association of the gene with RA susceptibility.

Table 1 .

 1

	Cases in this study	Controls
	n=182	n=194

Table 2 .

 2 Genotype and allele frequencies of CHI3L1polymorphisms in patients with RA and controls

	SNP	Allele	Case	Control	Genotype	Case	Control	HWE	HWE
			(frequency %)	(frequency %)		(frequency %)	(frequency	(p value	(p value
							%)	Case)	control)
	CHI3L1-1	C	280 (76.4)	302 (77.8)	CC	108(59.34)	116 (59.79)	0,897 x	0.524 x
	rs4950928	G	84 (23.1)	86 (22.2)	CG	64 (35.16)	70 (36.08)	0,898 #	0.517 #
					GG	10 (5.49)	8 (4.12)	0,837 §	0.677 §
	CHI3L1-2	C	259 (72.4)	281 (70.8)	CC	93 (51.09)	100 (51.54)	0.627 x	0.528 x
	rs10399931	T	106 (27.6)	107 (29.2)	CT	73 (40.10)	81 (41.75)	0.628 #	0.524 #
					TT	17 (9.34)	13 (6.70)	0.596 §	0.593 §
	X Pearson test
	# Llr test
	§ Exact test
	HWE: Hardy Weinberg equilibrium

The authors declare that they have no conflict of interest.

Acknowledgements

This work has been supported by grants OTKA 73247, OTKA77537, MRTN-CT-2005-019561, NKTH (National Research and Technology) TECH 08-A1/2-2008-0120, OTKA PD-76348. György Nagy and Peter Antal are J. Bolyai Research Fellows.

Conflict of interest


Dr Jochen Hardt
email: hardt@mail.uni-mainz.de

Malgorzata Dragan

Sonja Schultz

Katarzyna Schier

Comparison of childhood adversities and their possible consequences in Poland and Germany

Keywords: childhood adversities, family atmosphere, psychometric assessment, international survey

published or not. The documents may come

The comparison of childhood adversities and their possible consequences in

Poland and Germany

Running head: childhood adversities in Poland and Germany

Word Count: Adverse childhood experiences have been reported from countries all over the world. Worldwide, we face rates of childhood sexual abuse before the age of 14 of about 2% for boys and 5% for girls [START_REF] Andrews | Comparative risk assessment: child sexual abuse. Final report WHO Collaborating Centre on Evidence and Health Policy in Mental Health[END_REF]. The overall percentages for child maltreatment range from about 10% [START_REF] Finkelhor | Violence, abuse, and crime exposure in a national sample of children and youth[END_REF]) to about 50% [START_REF] Euser | Prevalence of child maltreatment in The Netherlands[END_REF]; such large variations are due to different definitions of maltreatment. Physical, sexual abuse and neglect are most apparent [START_REF] Dong | The interrelatedness of multiple forms of childhood abuse, neglect, and household dysfunction[END_REF]), but there are additional adverse childhood experiences, e.g. parental discord

or parental mental disorders such as depression and alcohol abuse, which may be associated with long-term sequelae (Hardt 2004;[START_REF] Hardt | Suicide attempts and retrospective reports about parent-child relationships: evidence for the affectionless control hypothesis[END_REF]). In addition, social, economic, and cultural circumstances have an impact on how children are perceived by parents, on child-rearing practices, and on aspects of the parent-child relationship [START_REF] Schier | Piekne brzydactwo. Problematyka obrazu ciala I jego zaburzen[END_REF]. Children who grow up in adverse social circumstances have a greater risk for unhealthy exposures such as environmental tobacco smoke and fewer opportunities for physical activity (Bolte et al.). Furthermore, children with low levels of education have a greater risk for mental health problems [START_REF] Havas | Mental health problems of Dutch adolescents: the association with adolescents' and their parents' educational level[END_REF]) and unhealthy behaviours such as smoking and risky alcohol use. [START_REF] Drieskens | Multiple risk behaviour: increasing socio-economic gap over time?[END_REF]. Likewise, childhood experiences of maltreatment are associated with psychiatric disorders and health-related risk behaviours [START_REF] Felitti | The Relationship of Adverse Childhood Experiences to Adult Medical Disease, Psychiatric Disorders, and Sexual Behavior: Implications for Healthcare[END_REF] as well as marital difficulties in adult life [START_REF] Dilillo | Child maltreatment history among newlywed couples: a longitudinal study of marital outcomes and mediating pathways[END_REF].

Poland and Germany have had different histories over the past 50 years. The period of poverty after World War II ended relatively quickly in Germany but was prolonged in Poland during the communist regime until 1989. Even after the end of that regime, Poland could only slowly and partly catch up to Western standards. communist eastern part and capitalist western part in 1989. There also were economic differences, i.e. in Germany the communist East was (and still is) poorer than the West, but the differences were smaller in comparison to the change of systems that people experienced in Poland.

METHOD

SAMPLE

Subjects were asked via Internet to fill out a survey containing about 280 items. The questions about childhood [START_REF] Hardt | Der Kindheitsfragebogen, ein Instrument zur Beschreibung der erlebten Kindheitsbeziehungen zu den Eltern[END_REF]

RESULTS

We present the results in four groups: (1) demographics and general background, (2) family problems (the image of the mother, the father, and their relationship), (3) forms of abuse, and (4) alcohol consumption and suicidal ideation).

1. Demographics and general background (Please insert Table 1 about here)

As seen in Table 1, there were slightly more females (about 55%) than males in both samples. The average age was about 39 years. Regarding current partner in life, most respondents from both countries were married or had been living with a partner for more than six months. In both countries, the older groups were more often married than the younger groups (X² = 131, p < .001). Regarding job status, Polish respondents designated themselves mostly as on level II of the Registrar General's Classification System [START_REF] Goldthorpe | The Social Grading of Occupations[END_REF]; in contrast, Germans settled mainly on level IIIa (X² = 204, p < .001). There were neither age nor sex differences.

Concerning religiousness, there were prominent differences between the two countries (X² = 314, p < .001). In Poland, almost 90% of the participants were Christians, whereas in Germany only about 50% were Christians. In contrast, the percentage of non-church members was about 50% in Germany, compared with only 10% in Poland. In addition, there was an age effect: older people tended to be more religious.

(Please insert Table 2 about here)

Polish subjects significantly more often reported that they believed they had been a planned child (80%), compared with Germans (50%; X² = 124, p < .001). No age effect was seen in either country. The rooms per person in the household differed significantly between the countries; in Germany there was more space (X² = 143, p < .001). Furthermore, there was an age effect; younger probands reported having more space.

A feeling of having felt secure at home was reported more often in Poland than in Germany (X² = 51.0, p < .001); no age effect was observed. Absence of a parent for more than six months was reported by 80% of the Poles, compared with only 23% of the Germans (X² = 319, p < .001), with no age effect. German and Polish subjects did not differ significantly in having grandparents who cared for them (X² = 7.52; p = .057). The number of siblings was smaller for the younger groups in both countries (X² = 23.3, p < .001); in Germany the difference was larger than in Poland. Having been successful at school was more often reported by Poles than by Germans (X² = 63.6, p < .001), whereas having been a member of a youth group was more often reported by Germans (X² = 22.7, p < .001).

2. Description of the family

Chronic maternal illness or disability did not differ between the countries but showed a strong age effect (Table 2). In the younger groups about 6% of mothers were said to have been chronically ill or handicapped; in the older groups the percentage was about 12% (X² = 11.6, p = .009). Regarding the question of whether their fathers were chronically ill or handicapped, German and Polish subjects again did not differ in their answers (X² = 5.03, p = .170); however, there was no age effect. Maternal chronic pain was reported more often in Poland than in Germany, and the rates in the older groups were about twice as high as in the younger groups (X² = 23, p < .001). Regarding paternal chronic pain, Germans reported higher values than Poles, and again the older groups reported more pain (X² = 11.5, p < .009). In Germany, 20% of the younger respondents and 26.8% of the older ones reported maternal mental illness, whereas in Poland only 11% of the younger respondents and 4% of the older ones did so (X² = 57, p < .001). Paternal mental illness in general was reported less frequently than maternal mental illness; rates were in the range of 5% except for young Germans, who reported about 14% (X² = 21.6, p < .001). Maternal alcohol problems were reported more often in Germany than in Poland (X² = 34.0, p < .001), with an age effect showing a higher percentage for the younger participants. Paternal alcohol problems were reported by about onequarter of the respondents, without any difference between countries and age groups (X² = 2.93, p < .402).

. Abuse (Please insert Table 3 about here)

Regular physical punishment was reported more often by the younger groups, and more often in Germany than in Poland (X² = 24.4, p < .001). Physical abuse was reported by about 15% of the respondents (X² = 1.80, p = .615) and threat of physical abuse by about 17% (X² = 1.77, p = .622), without differences between countries or age groups. Physical arguments between the parents were reported by about one-fourth of the subjects; also, no differences between the countries and age groups were observed (X² = 2.00, p = .573). However, when asked about the reasons for arguments between the parents, differences could be observed: the younger respondents in both countries reported arguments due to the temperaments of their parents more often (X² = 34.6, p < .001) than did the older respondents. Germans reported more parental arguments due to financial problems and jealousy than did Poles (X² = 14.5, p = .002; X² = 12.2, p = .007). An interacting age effect indicated jealousy as a more frequent reason for arguments between parents of older respondents in Germany, whereas in Poland parental arguments due to jealousy were reported more often by younger respondents. No differences were found regarding arguments between parents because of alcohol; the rate was constantly high, at about 25%.

Unwanted sexual experiences were reported more often in Germany than in Poland (X² = 12.7, p = .005), as were experiences that were considered to be sexual abuse (X² = 16.1, p < .001), i.e. in Poland about 5% and in Germany about 13% reported sexual abuse.

4. Alcohol consumption and suicidality (Please insert Table 4 about here)

About 20% of the subjects in the older groups reported that they never drink alcohol, compared with about 12% of the younger subjects (X² = 17.9, p < .001);

higher rates of never drinking were observed in Germany than in Poland. All four symptoms that were taken from the CAGE questionnaire were more often assented to by Poles than by Germans. In Poland no age effect was seen, whereas in Germany the rates of CAGE symptoms were higher for the younger respondents.

Reported suicidality was generally higher in Germany than in Poland (X² = 70, p < .001). This result holds true for all three categories: suicide attempts, suicide plans, and ideations. The data show that Poles of the older group, in particular, reported low suicidality.

The only significant predictor for suicide attempts in both country was childhood physical abuse (p < .001, table 5). The risk of reporting a suicide attempt was strongly increased in those participants who reported abuse (pseudo R² = 10,9%). It should be noted however, that other effects were close to significance, i.e. the interaction between childhood sexual abuse and country had a p value of p = .022.

Possible alcohol abuse was predicted by two variables: Gender and Country. Men drink more than women, Poles more than Germans. Both effects did not explain much variance, i.e. 2.3 %. Possible alcohol problems and reported suicide attempts were positively associated (X² = 27.27, p y .001), 20.4 % of the subjects with possible alcohol abuse reported at least one suicide attempt compared to 6.9 % of the others.

DISCUSSION

In summary, childhood in Poland was described consistently more in favourable terms than in Germany. This outcome might reflect true experiences, of course, but we believe an alternative explanation could be that there is some idealisation among Polish respondents. When we analysed the demographic data, some inconsistencies appeared that can be interpreted as suggesting possible idealisation. The Poles felt more secure at home during their childhoods than the

Germans; yet, 80% of the former reported that one of their parents was absent from home for a long period of time, i.e. mother or father was not available. Poles also think that they are highly professional, but a comparison of the data between

Poland and Germany shows an unrealistic or at least questionable tendency among Polish respondents when reporting their profession. In no country does more than one-half of the population belong to the Registrar General's Classification categories I and II ( high-and low-grade professional [START_REF] Goldthorpe | The Social Grading of Occupations[END_REF].

Regarding this variable, the Germans seem to be more realistic: only 20%-30% of them reported that they belonged in these two categories of profession. In addition,

Poles think of themselves as successful pupils at school much more than Germans do; admittedly, this finding also could reflect differences in the school systems.

Finally, the hypothesis of idealisation may be supported by the answer to the question of whether one thinks that she or he was a wanted child. Eighty percent of Poles believe they were wanted children, compared with only 50% of Germans.

This perception seems unrealistic high even when one considers that from 1956 to 1993 abortion was allowed in Poland during the first 12 weeks of pregnancy and was widely practiced.

The most striking findings among the German probands were the very high rates of mental problems or nervous disorders, particularly among their mothers, as well as high rates of suicide attempts, plans, and ideations reported for the probands themselves. The results show that Germans reported twice the rates of mental disorders in their parents than did Poles-with the exception of fathers in the older groups. The latter result could reflect the fact that these fathers were absent, most probably due to war [START_REF] Radebolt | Bez tchu i bez slowa. Wiez psychiczna i regulacja emocji u osób chorych na astme oskrzelowa[END_REF]. The former result may illustrate a state of poor mental health in Germany but also may be partly an effect of greater social acceptance of mental disorders in Germany than in Poland. Also striking in this survey was the high rate of childhood sexual abuse in Germany-it greatly exceeds the rates shown by previous surveys [START_REF] Wetzels | Gewalterfahrungen in der Kindheit: Sexueller Missbrauch, körperliche Misshandlung und deren langfristige Konsequenzen. Nomos, Baden-Baden World Health Organization[END_REF][START_REF] Andrews | Comparative risk assessment: child sexual abuse. Final report WHO Collaborating Centre on Evidence and Health Policy in Mental Health[END_REF].

No explanation for this effect could be found; in this regard, the Polish data are more plausible. Harsh regular punishment was reported in Germany more than twice as often as in Poland, an outcome that confirms the cliché that the Germans traditionally beat their children. Concerning alcohol, a strange pattern was seen in Germany: fathers were reported to have had as many alcohol problems as fathers in Poland and German mothers even more than Polish mothers, but the probands themselves did not feel bad or guilty about their drinking. It is not plausible that in a country where the parents drink, children do not drink. A representative survey using standardized methodology (CIDI: World Health Organization 1990) in Germany revealed a rate of 3.8 % of alcoholic depend subjects [START_REF] Meyer | Lebenszeitprävalenzen psychischer Störungen in der erwachsenen Allgemeinbevölkerung. Ergebnisse der TACOS-Studie[END_REF] comparable data for Poland were not found. A look at the objective data reveals that alcohol consumption in Germany was consistently about 10 litres per person and year (Statistisches Bundesamt 2009a), whereas in Poland it increased from about six litres in the years after the war to eight to nine at the millennium (Landberg 2008). Perhaps we can observe here an opposite tendency to the one concerning the idealisation pattern observed among the Polish group. The Germans might be trivialising their alcohol problems and underestimating the consequences of their alcohol consumption. This interpretation is supported by the results of a study by Stock et al. (2009), who asked students in six different countries if alcohol selling should be forbidden on the campus. In this study, 70 % of the Polish students consented, compared to only 20 % of the German students. Childhood physical abuse proved to be a strong risk factor for suicide attempts in both countries, a result found in Poland and Germany on a different samples before [START_REF] Dragan | Lifetime exposure to potentially traumatic events in a sample of alcoholdependent patients in Poland[END_REF][START_REF] Hardt | Childhood adversities and suicide attempts: a retrospective study[END_REF]. Surprisingly, possible alcohol abuse was predicted by sex and country only, no childhood adversity found entrance into the risk factor model. It is possible, that the CAGE-questions, even if widely used in psychiatry, partly measure a self critical reflection on one's own alcohol consume rather than abuse [START_REF] Chan | Detection by the CAGE of alcoholism or heavy drinking in primary care outpatients and the general population[END_REF].

Our results also reveal some interesting time trends in both countries. One trend concerns parental chronic illness and parental pain: the younger groups in both countries reported considerably fewer problems in the functioning of their parents than the older groups. We think this finding could reflect the effects of better economic and medical conditions and a longer break from the disturbing consequences of World War II. Another time trend is worrisome: regular (i.e.

habitual) harsh, physical punishment was reported more often by the younger cohorts than by the older ones. Of course, this result does not necessarily mean that physical abuse is increasing over time; indeed, some data from the US and the UK show an opposite trend [START_REF] Gilbert | Burden and consequences of child maltreatment in high-income countries[END_REF]. It is possible that the younger generation may respond to this item more sensitively; however, the positive time trend regarding sexual and physical abuse as observed in other countries cannot be postulated in Poland and Germany.

Summarising our results, we can say that the comparison of retrospective data on childhood and childhood adversities in Poland and Germany-two countries with different social and economic systems-reveals two different ways of coping.

The Poles have a good opinion of their parents and may partly regulate their emotions by drinking alcohol [START_REF] Taylor | Disorders of Affedt Regulation. Alexithymia in Medical and Psychiatric Illness[END_REF]Schier 2005). They practise idealisation, a mechanism that allows them to avoid mentalising, i.e. thinking about the existential, difficult problems of everyday life and asking questions about the past and about the intentions and emotions of their caregivers [START_REF] Allen | Mentalisierungsgestützte Therapie. Das MBT-Handbuch -Konzepte und Praxis[END_REF]. The Germans seem to be generally more open in their evaluation of the past but may tend to magnify other people's problems by trivialising their own.

Supplementing the focus of the discussion on the negative aspects of family image, our results also present some positive features of perceptions of childhood by residents of Poland and Germany. The mean values for the feeling of being secure at home ranged between 70% and 80% in both countries; this outcome indicates that most subjects at least felt subjectively secure within their families. We believe that this result can be explained partly by the presence of the grandparents in the children's upbringing; such presence was reported by more than one-half of the respondents from both countries. The role of an alternative caregiver in the physical and psychological development of a person is strongly emphasized in attachment theory [START_REF] Bowlby | Mental care and mental health[END_REF][START_REF] Bowlby | The nature of childs tie to his mother[END_REF][START_REF] Bowlby | Attachment and loss[END_REF][START_REF] Bowlby | Separation: anxiety and anger[END_REF][START_REF] Bowlby | Fifty Years of Attachment Theory[END_REF][START_REF] Schier | Piekne brzydactwo. Problematyka obrazu ciala I jego zaburzen[END_REF].

The study has various limitations.

(1) The present data were collected via Internet and are not representative of the populations of both countries. Participants were younger and better educated than average in both Poland and Germany. It is not fully known how Internet users differ from the general population. Therefore, this method of data collection may have caused a bias in the results.

(2) Even though the items were translated and back-translated and discrepancies discussed, it is still possible that the content was not identical. (3) In addition, there is always some concern that retrospective reports about childhood may be biased in some way. [START_REF] Hardt | Validity of adult retrospective reports of adverse childhood experiences: review of the evidence[END_REF] showed that in most cases this type of bias may be smaller than researchers fear; nevertheless, it cannot be ruled out totally.

Given the limitations discussed above, the present study demonstrates interesting differences and analogies between Germany and Poland; such comparisons illustrate the extent to which the image of oneself and of one's family can be linked to specific social, economic, and cultural factors. Our results might be directly useful for the purposes of educational policy-making when one considers the latest trends, which stress the importance of stimulating the development of mentalization. Mentalization refers to the capacity to think and talk about the past, present, and future of a person and to reflect on his or her social experiences and emotions [START_REF] Allen | Mentalisierungsgestützte Therapie. Das MBT-Handbuch -Konzepte und Praxis[END_REF]. These skills play an important role in the prevention of mental illness and in the development of a positive, realistic image of the self and other people [START_REF] Schier | Piekne brzydactwo. Problematyka obrazu ciala I jego zaburzen[END_REF].

  Abstract: 181 Text (w/o. List of references): ~ 3800, 5 tables 1. INTRODUCTION

  Unemployment, basically not existent during the communistic area, reached rates of about 20 % in 2002, and was associated with increased death rates particularly for suicide and as consequence of alcohol abuse (relative risks ~ 3: Zagozdzon et al. 2009). Still in 2009, the average income per month in Poland was € 730 (GUS 2009), whereas in Germany it was € 2500 (Statistisches Bundesamt 2009b). The aim of the present paper was to systematically compare reports from subjects who grew up in Poland with those who grew up in Germany during this period. In addition, childhood sexual and physical abuse as risk factors for suicide attempts and alcohol abuse were compared in both countries. Due to the communist era in Poland, we divided the sample at the age of 40. Because the survey was performed in 2008, the older individuals in the Polish sample grew up mainly under the communist regime; the younger persons experienced mainly capitalist social and economic rules. Germany underwent a union between its

Table 1 : Demographics

 1

	Poland	Germany

Table 2 : History within and outside the family and family problems

 2

	Poland	Germany

Acknowledgements

The present work was supported, in part, by the Heigl-Stiftung, Düsseldorf, and the Köhler-Stiftung, Essen.

Conflicts of Interest

-None declared.