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What predicts adjustment among law students? A longitudinal panel study.

Although at the time of this article's publication, many anecdotes and cross-sectional studies had reported that law students experience significant distress during their 1st year, few researchers had controlled for prelaw school status (e.g., M. Garrison, B. Tomko, & I. Yip, 1996; L. Guinier, M. Fine, J. Balin, A. Bartow, & D. L. Stachel, 1994), and only a single group of researchers had explored a psychosocial factor that predicted these changes. The present authors tested 3 sets of potential predictors of adjustment: sources of stress, coping strategies, and relationship factors. The present data replicated declines in students' psychological health, physical health, and attitudes toward law over the 1st year of school. That result supports the generalizability and currency of previous studies. In contrast to other researchers, the present authors found few gender differences. Less relationship happiness, less emotional support, and use of less active coping tactics at the beginning of the year predicted poorer outcomes at the end of the year. Strain from academic pressures, lack of personal time, and social isolation were correlated with poorer outcomes.

Adaptation, Psychological↗

Stressful events related to childbearing in African-American women. A pilot study.

This pilot study replicated the Arizmendi and Affonso study that identified the frequency and intensity of stressors related to childbearing. The original study (n = 221) targeted chiefly middle-class white women. To date, there is no literature on stressful events as reported by African-American childbearing women. It was hypothesized that African-American women would identify differential patterns of stressful events in childbearing. A convenience sample of 50 African-American childbearing women were interviewed. Demographics were presented and compared with the original study. The frequency and intensity of stressors were analyzed and compared. It was proposed that the differential stressors between the chiefly white middle-class sample and the African-American sample relates to both the life experiences and the differential birth outcomes of African-American childbearing women. Areas for future research are targeted.

Adult↗

Oxidative stress and diabetic vascular complications.

Long-term vascular complications still represent the main cause of morbidity and mortality in diabetic patients. Although prospective randomized long-term clinical studies comparing the effects of conventional and intensive therapy have demonstrated a clear link between diabetic hyperglycemia and the development of secondary complications of diabetes, they have not defined the mechanism through which excess glucose results in tissue damage. Evidence has accumulated indicating that the generation of reactive oxygen species (oxidative stress) may play an important role in the etiology of diabetic complications. This hypothesis is supported by evidence that many biochemical pathways strictly associated with hyperglycemia (glucose autoxidation, polyol pathway, prostanoid synthesis, protein glycation) can increase the production of free radicals. Furthermore, exposure of endothelial cells to high glucose leads to augmented production of superoxide anion, which may quench nitric oxide, a potent endothelium-derived vasodilator that participates in the general homeostasis of the vasculature. In further support of the consequential injurious role of oxidative stress, many of the adverse effects of high glucose on endothelial functions, such as reduced endothelial-dependent relaxation and delayed cell replication, are reversed by antioxidants. A rational extension of this proposed role for oxidative stress is the suggestion that the different susceptibility of diabetic patients to microvascular and macrovascular complications may be a function of the endogenous antioxidant status.

Diabetes Mellitus, Type 1↗

Expressed emotion research in schizophrenia: theoretical and clinical implications.

The expressed emotion (EE) measure is a robust predictor of relapse in schizophrenia. At least twelve studies from a range of cultures have now shown this, although the authors of one maintain their findings are the result of confounding factors. A thirteenth study which failed to demonstrate a predictive effect was seriously weakened by methodological defects. There is now also evidence for the construct validity of EE, which has been shown to reflect ongoing family interactions. High EE relatives display less effective coping responses, and may adversely affect the patient by creating an unpredictable environment. EE may change with time, and probably reflects the interaction of external stresses, the real problems with the patient, and inappropriate coping responses. The association of high EE with arousal in the patient, as indicated by skin conductance abnormalities, has now been replicated. Although the EE phenomenon can be subsumed under a vulnerability-stress model, the way in which it might mediate relapse has not as yet been specified. Interventions have been successful in reducing relapse, and do so by increasing the tolerance and coping skills of the relatives, and by establishing more realistic expectations. As most have also involved the patient in the process of treatment, they have not fully resolved the question of causal direction. Future studies will clarify these issues, but will not detract from the value that EE has already had in energizing research. It has also provided a framework within which clinicians have begun to recognize and deal with the disabling problems that beset schizophrenic patients and their families.

Emotions↗

Need for DNA topoisomerase activity as a swivel for DNA replication for transcription of ribosomal RNA.

Yeast strains with mutations in the genes for DNA topoisomerases I and II have been identified previously in both Saccharomyces cerevisiae and Schizosaccharomyces pombe. The topoisomerase II mutants (top2) are conditional-lethal temperature-sensitive (ts) mutants. They are defective in the termination of DNA replication and the segregation of daughter chromosomes, but otherwise appear to replicate and transcribe DNA normally. Topoisomerase I mutants (top1), including strains with null mutations are viable and exhibit no obvious growth defects, demonstrating that DNA topoisomerase I is not essential for viability in yeast. In contrast to the single mutants, top1 top2 ts double mutants from both Schizosaccharomyces pombe and Saccharomyces cerevisiae grow poorly at the permissive temperature and stop growth rapidly at the non-permissive temperature. Here we report that DNA and ribosomal RNA synthesis are drastically inhibited in an S. cerevisiae top1 top2 ts double mutant at the restrictive temperature, but that the rate of poly(A)+ RNA synthesis is reduced only about threefold and transfer DNA synthesis remains relatively normal. The results suggest that DNA replication and at least ribosomal RNA synthesis require an active topoisomerase, presumably to act as a swivel to relieve torsional stress, and that either topoisomerase can perform the required function (except in termination of DNA replication where topoisomerase II is required).

DNA Replication↗

Assessment of combat-related stress and physical symptoms of Gulf War veterans: criterion validity of selected hand test variables.

We examined the utility of selected Hand Test (Wagner, 1983) variables in relation to posttraumatic stress and physical symptoms in Gulf War (GW) veterans. In this study, we sought to replicate and expand on prior empirical findings that have demonstrated efficacy of the Hand Test in the assessment of posttraumatic stress disorder (PTSD; Walter, Hilsenroth, Arsenault, Sloan, & Harvill, 1998). Based on this previous research, Hand Test variables were selected a priori and examined across three groups of veterans: (a) a control group of participants who were in a reserve unit not deployed to the GW theater of operations, (b) a subclinical group of deployed GW veterans who reported 1 to 5 Diagnostic and Statistical Manual of Mental Disorders (4th ed. [DSM-IV]; American Psychiatric Association, 1994) criteria for PTSD, and (c) a group of deployed GW veterans who met DSM-IV criteria for PTSD. Analyses demonstrated significant differences across the three groups and significant relationships among selected Hand Test variables with the number of DSM-IV symptoms of PTSD reported in the interviews as well as with the number of physical problems reported by these veterans. We discuss these findings in relation to the assessment and treatment of posttraumatic stress symptomatology.

Adult↗

DNA topoisomerase activity is required as a swivel for DNA replication and for ribosomal RNA transcription.

Yeast strains with mutations in the genes for DNA topoisomerases I and II have been identified previously. The topoisomerase II mutants (top2) are conditional-lethal, temperature-sensitive mutants defective in the termination of DNA replication and the segregation of daughter chromosomes. The topoisomerase I mutants (top1), including strains with null mutations, are viable and exhibit no obvious growth defects, demonstrating that DNA topoisomerase I is not essential for viability in yeast. In contrast to the single mutants, top1 top2 double mutants grow poorly at the permissive temperature and stop DNA and ribosomal RNA synthesis at the restrictive temperature. Transfer RNA synthesis remains relatively normal. The rate of polyA+ RNA synthesis is down about 3-fold in the double mutant at the non-permissive temperature but the synthesis of three specific RNA polymerase II transcripts is unaffected. The results suggest that DNA replication and at least ribosomal RNA synthesis require an active topoisomerase, presumably to act as a swivel to relieve torsional stress, and that either topoisomerase can perform the required function (except for termination of DNA replication where topoisomerase II is required).

DNA Replication↗

Computation of DNA structural variability--a new predictor of DNA regulatory regions.

MOTIVATION: Local separation of the two strands of the DNA duplex is an essential step in important biological activities, including the initiation of transcription and replication. This conformational transition occurs in response to imposed stresses, which are stringently regulated in vivo. RESULTS: This paper describes two computational methods to analyse this phenomenon: an approximate statistical mechanical method and a Monte Carlo sampling technique. Analysis of genomic DNA sequences shows that sites of predicted duplex destabilization are closely associated with regions regulating transcription, with the most destabilized sites coinciding with 3' gene termini. Experimental results supporting this conclusion are described. The incorporation of this technique into computational searches for regulatory regions is discussed. AVAILABILITY: Because the programs implementing these calculations are complex to use and not completely developed, they have not been released yet. However, the author will analyze any DNA sequences upon request. Sequences may be submitted electronically to benham/msvax.mssm.edu.

DNA↗

CspD, a novel DNA replication inhibitor induced during the stationary phase in Escherichia coli.

CspD is a stationary phase-induced, stress response protein in the CspA family of Escherichia coli. Here, we demonstrate that overproduction of CspD is lethal, with the cells displaying a morphology typical of cells with impaired DNA replication. CspD consists mainly of beta-strands, and the purified protein exists exclusively as a dimer and binds to single-stranded (ss)DNA and RNA in a dose-dependent manner without apparent sequence specificity. CsdD effectively inhibits both the initiation and the elongation steps of minichromosome replication in vitro. Electron microscopic studies revealed that CspD tightly packs ssDNA, resulting in structures distinctly different from those of SSB-coated DNA. We propose that CspD dimers, with two independent beta-sheets interacting with ssDNA, function as a novel inhibitor of DNA replication and play a regulatory role in chromosomal replication in nutrient-depleted cells.

Amino Acid Sequence↗

Mitochondrial abnormalities and oxidative imbalance in Alzheimer disease.

A number of mitochondrial and metabolic abnormalities were identified in the hippocampal neurons of Alzheimer disease compared to age-matched controls. Hippocampal neurons are the most vulnerable to disease-associated pathology (i.e., cell death and proteinaceous lesions) and contain numerous markers of oxidative stress. Interestingly we found that the levels of mitochondrial DNA and cytochrome oxidase-1 in these neurons are markedly increased compared with those of age-matched control brains, even though the number of mitochondria per neuron is decreased. We hypothesize that the increased levels of mitochondrial DNA and cytochrome oxidase-1 may reflect an attempt by oxidatively-challenged neurons to replicate mitochondria, albeit unsuccessfully, as a response to the energetic/oxidative stress. Indeed, in this context, numerous signs of mitosis are observed in pyramidal neurons. Mitotic signals that promote cell cycle re-entry might be expected to also signal the synthesis of new mitochondria. Alternatively, these abnormalities may indicate altered turnover of mitochondrial components as a result of reduced degradation of mitochondrial byproducts or altered mitochondrial transport that redistributes mitochondrial DNA and cytochrome oxidase-1 to the cell body.

Alzheimer Disease↗

The effect of iron overload on in vitro HIV-1 infection.

BACKGROUND: It has been shown that Fe is required by HIV-infected cells for production of viral particles. Excess iron in the cell is detrimental to the host but beneficial to the pathogen. OBJECTIVES: Here, we investigated the effect of excess Fe (overload) and chelation of the metal on in vitro HIV infection by assessing host cell responses (viability/death, stress protein expression and cytokine production) as well as virus replication (core protein content and enzyme activity). RESULTS AND CONCLUSION: Excess iron decreased viability (21%, P<0.01) of HIV-infected cells, increased p24 levels by 8.6% (P=0.32) and elevated reverse transcriptase (RT) activity (81.7%, P<0.01). The stimulation of viral replication was decreased when Fe was first complexed to desferrioxamine (DFO). DFO alone (in the absence of excess Fe), lowered cell viability (35%, P=0.039) and in the presence of virus lowered both p24 levels (66%, P=0.054) and RT activity (43%, P<0.01) and unexpectedly increased cell viability (25%, P=0.01047). Interleukin-2 (IL-2) production of infected cells was completely inhibited by DFO and excess iron while stress protein (Hsp70) levels were lowered in the presence of HIV in combination with excess iron (37%, P<0.01) or DFO (47.2%, P<0.01) when compared to untreated cells. According to flow cytometric data, HIV infection caused a two-fold increase in the numbers of necrotic (P=0.006) and decreased apoptotic cells (28.5%, P=0.15) cells. These findings indicate that Fe overload associated with HIV infection is detrimental to host cell responses against viral infection and that chelation can prevent and/or reverse this effect.

Cell Survival↗

HIV: reactive oxygen species, enveloped viruses and hyperbaric oxygen.

This paper demonstrates that there are many examples in the literature of contradictory data concerning reactive oxygen intermediates (ROIs), responsible for producing cellular oxidative stress (OS), and their enhancement or diminution of viral replication. Nevertheless, ROIs repeatedly have been shown to be virucidal against enveloped-viruses, like the human immunodeficiency virus (HIV). Hyperbaric oxygen therapy (HBOT) increases the production of ROIs throughout the body, leaving no safe harbor for the virus to hide outside the genome. This technique already has been tried on acquired immune deficiency syndrome (AIDS) patients, with exciting results. Historically, the biggest setback to demonstrating HBO's antiviral effects has been the investigator's folly of studying non-enveloped viruses or failing to initiate ROI production. ROIs specifically attack areas of unsaturation occurring in the polyunsaturated fatty acids of cell membranes and viral envelopes. Moreover, it consistently has been shown that a peroxidized viral envelope breaches, and a breached viral envelope causes viral disintegration.

HIV↗

Fatal Sindbis virus infection of neonatal mice in the absence of encephalitis.

A comparative pathogenesis study was performed in neonatal mice using a molecularly cloned laboratory variant of Sindbis strain AR339, designated TRSB, and a single-site attenuated mutant of TRSB derived by site-directed mutagenesis of the E2 glycoprotein from Ser to Arg at residue 114 (TRSBr114). TRSB caused 100% mortality with an average survival time of 3.0 +/- 0.7 days, whereas mice inoculated with TRSBr114 exhibited an attenuated disease course with 46% mortality and an extended average survival time of 7.5 +/- 3.4 days for those animals that died. Reduced virulence of TRSBr114 was characterized by delayed appearance of detectable virus, relative to TRSB, and by lower peak virus titers in both sera and brains of infected mice. TRSB infection induced very high peak serum titers of interferon alpha/beta (215,000 units/ml compared to 2100 units/ml for TRSBr114). In situ hybridization analysis demonstrated replication of TRSB in brain, but only minimal histopathological changes and no evidence of encephalitis were observed. However, extensive extraneural lesions and viral replication were found in skin, connective tissue, and muscle. Moreover, dramatic involution of the thymus and loss of hematopoietic tissues were observed in the absence of virus replication at these sites, suggesting the involvement of a systemic physiological stress response in TRSB infection. TRSBr114 infection did not cause thymic lesions. Otherwise, the attenuated mutant demonstrated a similar pattern of tissue and organ involvement, but lesions and positive in situ hybridization signal were much more limited in scope and intensity compared to TRSB. TRSBr114-infected mice developed myositis and encephalomyelitis approximately 6 days postinfection. Therefore, TRSB-infected animals may succumb to an early syndrome associated with the stress response, preventing their survival for a time sufficient for the development of encephalitis. Alternatively, a systemic stress response, as evidenced by thymic involution, may result in immunosuppression, thus contributing to the absence of encephalitis. In any event, the attenuating mutation in the E2 glycoprotein significantly altered the course of Sindbis-induced disease by limiting virus replication and associated damage early in infection. Mutant-infected animals survived beyond Day 4 and progressed to a classical encephalomyelitis from which about half recovered.

3T3 Cells↗

A randomized, controlled trial of massage therapy as a treatment for migraine.

BACKGROUND: Migraine is a distressing disorder that is often triggered by stress and poor sleep. Only one randomized controlled trial (RCT) has assessed the effects of massage therapy on migraine experiences, which yielded some promising findings. PURPOSE: An RCT was designed to replicate and extend the earlier findings using a larger sample, additional stress-related indicators, and assessments past the final session to identify longer-term effects of massage therapy on stress and migraine experiences. METHODS: Migraine sufferers (N = 47) who were randomly assigned to massage or control conditions completed daily assessments of migraine experiences and sleep patterns for 13 weeks. Massage participants attended weekly massage sessions during Weeks 5 to 10. State anxiety, heart rates, and salivary cortisol were assessed before and after the sessions. Perceived stress and coping efficacy were assessed at Weeks 4, 10, and 13. RESULTS: Compared to control participants, massage participants exhibited greater improvements in migraine frequency and sleep quality during the intervention weeks and the 3 follow-up weeks. Trends for beneficial effects of massage therapy on perceived stress and coping efficacy were observed. During sessions, massage induced decreases in state anxiety, heart rate, and cortisol. CONCLUSIONS: The findings provide preliminary support for the utility of massage therapy as a nonpharmacologic treatment for individuals suffering from migraines.

Adaptation, Psychological↗

Occupational stress and strain in the Naval Service: 1999 and 2004.

BACKGROUND: Surveys of occupational stress were undertaken in 1999 and 2004. OBJECTIVE: To measure the prevalence of psychological strain and exposure to work-related stressors in personnel. METHOD: A cross-sectional survey using a validated, reliable questionnaire was undertaken in 1999 and was replicated in 2004. The data were combined and models of stress-strain were developed for male and female personnel in the Royal Navy (RN) and males in the Royal Marines (RM). RESULTS: The response rates were 78% in 1999 and 67% in 2004. Strain prevalence was 32% in 1999 and 33.5% in 2004. Strain rates were higher in females than in males and in personnel serving at sea. Reduced organizational commitment was associated with strain in males and females. Dissatisfaction with the physical work environment was associated with strain in RN females and RM. Role conflict was associated with strain in all groups. Work-family conflict was associated with strain in males, but not in females. The models accounted for 20-30% of the variance in strain. CONCLUSION: The strain rate in the Naval Service appeared to be similar to that in the other service occupations such as the UK Police, as did the sex difference in strain. The strain rate and stressor exposure ratings were remarkably stable over the period. Role conflict was found to be a generic stressor associated with strain.

England↗

Changes in gene expression following high-temperature adaptation in experimentally evolved populations of E. coli.

Transcription profiling (quantitative analysis of RNA abundance) can provide a genome-wide picture of gene expression changes that accompany organismal adaptation to a new environment. Here, we used DNA microarrays to characterize genome-wide changes in transcript abundance in three replicate lines of the bacterium E. coli grown for 2,000 generations at a stressful high temperature (41.5 degrees C). Across these lines, 12% of genes significantly changed expression during high-temperature adaptation; the majority of these changes (55%) were less than twofold increments or decrements. Thirty-nine genes, four times the number expected by chance alone, exhibited moderately or highly replicated expression changes across lines. Expression changes within a priori defined functional categories showed an even greater level of replication than did individual genes. Expression changes in the phenotypically defined stress genes and adaptation functional categories were important in evolutionary adaptation to high temperature.

Adaptation, Physiological↗

Meditation practice as related to occupational stress, health and productivity.

This article reviews three studies giving evidence on the effects of meditation practice on employees' health in the work setting. Although there may be a beneficial role for meditation, unfortunately, these findings await further replication so it would be premature to conclude that meditation practice reduces occupational stress.

Achievement↗

Home environmental consequences of commute travel impedance.

The physical and perceptual dimensions of commuting travel impedance were again found to have stressful consequences in a study of 99 employees of two companies. This quasi-experimental replication study, which focuses here on home environment consequences, investigated the effects of physical impedance and subjective impedance on multivariate measures of residential satisfaction and personal affect in the home. Both sets of residential outcome measures were significantly related to the two impedance dimensions. As predicted, gender was a significant moderator of physical impedance effects. Women commuting on high physical impedance routes were most negatively affected. Previously found subjective impedance effects on negative home mood, regardless of gender, were strongly replicated with several methods and were buttressed by convergent results with objective indices. The theoretical conjecture that subjective impedance mediates the stress effects of physical impedance was supported by the personal affect cluster but only for one variable in the residential satisfaction cluster. Traffic congestion has increased in metropolitan areas nationwide, and commuters, families, and organizations are absorbing associated hidden costs. The results are reviewed in terms of our ecological model, and the moderating effects of gender are discussed in terms of choice and role constraints.

Adult↗