Diffusion MR imaging acquisition and analytics for microstructural delineation in pre-clinical models of TBI.

Significant progress has been made toward improving both the acquisition of clinical diffusion-weighted imaging (DWI) data and its analysis in the uninjured brain, through various techniques including a large number of model-based solutions that have been proposed to fit for multiple tissue compartments, and multiple fibers per voxel. While some of these techniques have been applied to clinical traumatic brain injury (TBI) research, the majority of these technological enhancements have yet to be fully implemented in the preclinical arena of TBI animal model-based research. In this review, we describe the requirement for preclinical, MRI-based efforts to provide systematic confirmation of the applicability of some of these models as indicators of tissue pathology within the injured brain. We review how current DWI techniques are currently being used in animal TBI models, and describe how both acquisition and analytic techniques could be extended to leverage the progress made in clinical work. Finally, we highlight remaining gaps in the preclinical pipeline from data acquisition to final analysis that currently have no real, preclinical-based correlate.

Adhesion and growth of osteoblast-like cells on laser-engineered porous titanium surface: expression and localization of N-cadherin and beta-catenin.

Response of different types of cells on biomaterials is crucial for the applications of tissue engineering and regenerative medicine. It is recognized that cell behaviour depends largely on material surface characteristics. The purpose of this study was to define the biologic response of MG63 cells to the innovative patented surface SYNTHEGRA. MG63 morphology and distribution on the three different titanium disk surfaces (sandblasted, smooth, and laser-treated) were evaluated by microscopy analysis after staining with hematoxylin and eosin. Cell adhesion was determined by crystal violet assay at 48 h while proliferation and cytotoxicity were performed by MTT assay at 24, 48, 72 and 240 h. The expression and localization of N-cadherin and beta-catenin were studied by immunofluorescence and confocal microscopy. At 48 h the adhesion was similar in all titanium surfaces, no difference in cell viability were observed in all titanium disks when compared with controls, while the cell growth on laser-treated disks was significantly higher at 240 h than at 24 and 72 h. Morphological analysis show that cells are aligned along the grooves and inside the cavities. beta-catenin signal appeared more diffuse and localized underneath the cell membrane, while N-cadherin signal was fainter in cells grown on SYNTHEGRA surface. This work put into evidence the performance of newly designed laser-micromachined surface for adhesion, growth and distribution of human osteoblast-like cells. SYNTHEGRA surface inducing modification of N-cadherin and beta-catenin expression and localization, are suggestive of cells undergoing differentiation towards osteocytes and could be particularly suited for immediate load implant procedures.

Cynicism, social support, and cardiovascular reactivity.

This study examined whether highly cynical individuals benefit less from social support during an acute stressor than individuals low in cynicism. College students (52 men, 52 women) performed a stressful speech task alone or in the presence of a supportive confederate. There was an interactive effect of social support and cynicism on cardiovascular reactivity: Low cynicism participants who received support has smaller increases in blood pressure during the speech than low cynicism participants without support and high cynicism participants with or without support. Participants' psychological stress appeared to mediate the main effects of support on blood pressure reactivity, but not the Support x Cynicism interaction. Results suggest that cynical attitudes may undermine the stress buffering potential of interpersonal support.

The role of social and cognitive processes in children's adjustment to community violence.

This study examined associations of community violence exposure and psychological well-being among 99 8-12 year old children (M = 10.7 years) using home interviews with mothers and children. Both moderators and mediators of the links between violence exposure and well-being were tested. After demographics and concurrent life stressors were controlled for violence exposure was significantly associated with intrusive thinking, anxiety, and depression. Regression analyses indicated that intrusive thinking partially mediated associated between violence exposure and internalizing symptoms. Planned comparisons revealed that violence exposure had the strongest effect on well-being among children with low social support or high levels of social strains. Furthermore, children with high levels of intrusive thinking were most likely to show heightened internalizing symptoms when they had inadequate social support.

Social conflict, social support, and psychological distress: evidence of cross-domain buffering effects.

A longitudinal study examined the relative and joint effects of perceived social support and social conflict on psychological distress in 228 college students. Women had higher perceived social support from roommates and friends and less conflict with roommates than did men; there were no gender differences in level of conflict with friends or psychological distress. Roommate conflict predicted increases in psychological distress over time; this effect was attenuated by high levels of perceived social support from friends. Friend conflict also predicted increases in psychological distress over time; this effect was attenuated by high levels of perceived social support from roommates. These results show the importance of negative and positive aspects of social experiences to emotional functioning and the importance of compensatory social support for individuals facing social conflicts.

Expressive writing moderates the relation between intrusive thoughts and depressive symptoms.

The author investigated whether expressive writing enhances emotional adaptation to a stressful event (graduate entrance exams) by reducing event-related intrusive thoughts or by desensitizing people to such thoughts. Participants in the experimental group, who were instructed to write their deepest thoughts and feelings about the exam, exhibited a significant decline in depressive symptoms from 1 month (Time 1) to 3 days (Time 2) before the exam. Participants in the control group, who wrote about a trivial topic, maintained a relatively high level of depressive symptoms over this same period. Expressive writing did not affect the frequency of intrusive thoughts, but it moderated the impact of intrusive thoughts on depressive symptoms. Specifically, intrusive thoughts at Time 1 were positively related to depressive symptoms at Time 2 in the control group and were unrelated to symptoms in the expressive writing group.

Household crowding and social support: a quasiexperimental analysis.

People often cope with crowded living conditions by socially withdrawing from their housemates. This coping strategy may overgeneralize, influencing social interactions with others outside the home. In a stressful laboratory situation, Ss from crowded homes, in comparison with uncrowded counterparts, are less likely to seek support from a confederate and rate the confederate as less supportive. Moreover, Ss from crowded homes are less likely to offer support to a confederate in need. These differences in social interaction behaviors appear to be attributable to crowded residents' social withdrawal.

Talking facilitates cognitive-emotional processes of adaptation to an acute stressor.

The authors examined the influence of talking and the social context of talking on cognitive-emotional processes of adjustment to stressors. Two hundred fifty-six undergraduates viewed a stressful stimulus and were then assigned to a no-talk control condition or 1 of 3 talk conditions: talk alone, talk to a validating confederate, or talk to an invalidating confederate. Two days later, they were reexposed to the stressor. Compared with individuals in the no-talk condition, those in the talk alone and validate conditions had a lower level of intrusive thoughts in the 2-day interim, and they had lower perceived stress when reexposed to the stressor. The effects of talking and validation on perceived stress appeared to be mediated by lowered intrusions. The benefits of talking were diluted when disclosures were invalidated. These findings suggest that talking about acute stressors can facilitate adjustment to stressors through cognitive resolution.

Dynamic role of social support in the link between chronic stress and psychological distress.

How a chronic environmental stressor can interfere with the buffering effects of social support by eroding social support was analyzed in this prospective, longitudinal study. A classic buffering effect of support was found after 2 months of exposure to the stressor, household crowding. Crowded residents with low perceived support had greater increases in psychological distress than did crowded residents with high perceived support. However, after 8 months exposure the buffering effect disappeared. Moreover, greater crowding had become directly associated with lower support, which in turn was associated with greater increases in psychological distress. All analyses controlled for prior distress. Under some types of chronic stress, the buffering effects of social support may be short-lived because the stressor eventually erodes social support.

Residential density and psychological health: the mediating effects of social support.

People report excessive, unwanted social interactions, insufficient privacy, and are observed to be more socially withdrawn under crowded living conditions. If people socially withdraw from one another as a way to cope with crowding, this could lead to an unintended side effect of breakdowns in socially supportive relationships. A breakdown in socially supportive relationships could, in turn, account for some of the pathological consequences of chronic, high density living conditions. An empirical study of 175 male heads of household among inner city residents in India suggests that the adverse effects of residential crowding on psychological health are mediated by a breakdown of social support systems. The study also points to the value of examining social support as an endogenous variable in the stress and health process.

Cross-cultural differences in tolerance for crowding: fact or fiction?

It is widely believed that cultures vary in their tolerance for crowding. There is, however, little evidence to substantiate this belief, coupled with serious shortcomings in the extant literature. Tolerance for crowding has been confused with cultural differences in personal space preferences along with perceived crowding. Furthermore, the few studies that have examined cultural variability in reactions to crowding have compared subgroup correlations, which is not equivalent to a statistical interaction. Although the authors found a statistical interaction indicating that Asian Americans and Latin Americans differ in the way they perceive crowding in comparison to their fellow Anglo-American and African American citizens, all four ethnic groups suffer similar, negative psychological distress sequelae of high-density housing. These results hold independently of household income.

Social constraints, intrusive thoughts, and depressive symptoms among bereaved mothers.

The study examined how social constraints on discussion of a traumatic experience can interfere with cognitive processing of and recovery from loss. Bereaved mothers were interviewed at 3 weeks (T1), 3 months (T2), and 18 months (T3) after their infants' death. Intrusive thoughts at T1, conceptualized as a marker of cognitive processing, were negatively associated with talking about infant's death at T2 and T3 among socially constrained mothers. The reverse associations were found among unconstrained mothers. Controlling for initial level of distress, there was a positive relation between T1 intrusive thoughts and depressive symptoms over time among socially constrained mothers. However, higher levels of T1 intrusive thoughts were associated with a decrease in T3 depressive symptoms among mothers with unconstrained social relationships.

Daily hassles and chronic strains: a hierarchy of stressors?

Among 105 poor, male heads of household in an urban center of India, common daily hassles were similar to those experienced by individuals from economically advantaged, western countries. However, we did not replicate the correlation between hassle frequency and mental health problems that has been previously found in a middle-class, western sample. In contrast to daily hassles, which include low-intensity, relatively discrete stressors (e.g. disagreement with spouse, missing a bus), chronic strains include ongoing social and environmental conditions that represent high-intensity stressors (e.g. substandard housing, inadequate access to water) that threaten survival. We found that chronic strains were associated with greater levels of psychosomatic symptomatology, as well as lower perceived social support. Furthermore, the correlation between chronic strains and psychosomatic symptoms increased when the effects of income were statistically controlled, suggesting that income attenuates the effects of chronic strains and that chronic strains affect symptoms independent of income. In sum, chronic strains may be a more valid and potent stressor than daily hassles in poor, urban populations in developing countries.

Social hassles and psychological health in the context of chronic crowding.

Data are presented on the interactive effects of an enduring environmental stressor with acute, daily social stressors on psychological distress. A cross-sectional study of males in urban India and a longitudinal study of male and female American college students examined the interplay of these two types of stressors. In India, social hassles in the home predicted psychological symptoms only among residents of crowded homes, after statistically adjusting for income. In America, the interaction between social hassles and crowding was replicated in analyses adjusting for prior psychological symptoms, prior social acquaintanceship with housemates, and income. A six-month follow-up study with the American sample replicated the interaction. In all three analyses of the social hassle-crowding interaction, there was a main effect of crowding but no main effect of social hassles on psychological symptoms. These findings suggest that some chronic environmental stressors may increase the impact of acute social stressors, and highlight the importance of examining contextual factors in the stress and health process.

Distorting children's reports and interpretations of events through suggestion.

Fifty-four children (33 girls and 21 boys), 4 to 6 years old, participated in an experiment examining the effects of leading interviews on their interpretations and factual recall of an interaction with a teaching assistant (TA). Children were either familiar or unfamiliar with the TA and were interviewed in either an incriminating or a neutral manner. In comparison with neutral-interview children, incriminating-interview children made more cued-recall errors and endorsed more biased interpretations of the TA's actions. Familiarity with the TA had limited effects on free recall and interpretations of the TA's actions and had no effect on cued recall. Results indicated that 4- to 6-year-olds will produce misleading reports about their interactions with either familiar or unfamiliar adults when they are prompted to do by an opinionated adult interviewer.

Osteoid osteoma of the clavicle.

We describe a case of osteoid osteoma of the clavicle in an Olympic free-style wrestler who presented to us with persistent and increasingly elevated pain in his right shoulder. Originally a persistent injury was considered to be causing the pain, however, the correct diagnosis was made three months after the onset of the symptoms. Even in sportsman where muscle pain is commonplace, non-traumatic conditions should be considered in the presence of persistent and increasingly elevated pain that is not relieved by rest and physiotherapy.

[The Japanese community in Argentina]. / La colectividad japonesa en la Argentina.

"Based on original survey data and census materials, the authors estimate the Japanese community in Argentina comprises about 10,000 native Japanese and some 40,000 ethnic Japanese born in Argentina. A complete picture is given of this community, including its evolution since the early arrivals around 1900. Data cover several aspects: demographic traits, socio-economic origin of immigrants, present employment structure, education, level of living, degree of acculturation in Argentina, intensity of connections with Japan, membership and participation in community organisations." (SUMMARY IN ENG)

Problems confronting migrants and members of their families when they return to their country of origin.

PIP: The problems which migrants and their families face when they return to their own country arise from the personal circumstances of the individuals themselves as well as the characteristics of both the country of origin and the host country. A great variety of conflicts can arise during reintegration and the interrelation between them is complex. Nevertheless, some problems occur more frequently than others; a number of the most common include the following: 1) reintegrating the return migrant into the labor force is very difficult, particularly when unemployment is a problem in his homeland. 2) Degrees earned abroad often do not transfer from one high school or university to another at the same academic level. 3) Most returning migrant workers lose their retirement benefits acquired during the period of emigration because of no social security convention between the countries concerned. 4) Patriotic feelings and ties to family and friends lead the migrant to gloss over the real problems he faces. 5) Migrant children commonly face problems related to education because of differences between languages, teaching contents, and educational methods practiced in the two countries. Recommendations to relieve these and other problems migrants face upon reintegration include: 1) efforts should be made to orient return migration when jobs are available; 2) cultural agreements allowing recognition of studies and accreditation of degrees and diplomas should be promoted; 3) social security conventions between countries should be extended to include the transfer of benefits and recognition of years of work; 4) priority should be given to educational problems faced by migrant children with a dual sociocultural identity; and 5) assistance should be given to countries in carrying out empirical studies on reintegration problems and measures to solve them.^ieng

Problems and prospects for the social support-reactivity hypothesis.

Social support and integration have been linked to health and longevity in many correlational studies. To explain how social relationships might enhance health, investigators are examining the effects of social support on physiological processes implicated in disease. Much of this research focuses on testing the social support-reactivity hypothesis, which maintains that social support enhances health by reducing psychobiologic reactivity to stressors. This article identifies the basic assumptions, problems, and prospects of this research endeavor. The major problems discussed include: (a) inconsistent findings across studies; (b) unidentified cognitive and emotional mediators; (c) individual differences in response to social support; and (d) a lack of experimental studies on the role of social support in adjustment to chronic stress. Besides raising consciousness about these problems, I offer ideas for advancing research in this area.