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Find video protocols related to scientific articles indexed in Pubmed.
A longitudinal investigation of changes to social resources associated with psychological distress among Kurdish torture survivors living in Northern Iraq.
J Trauma Stress
PUBLISHED: 07-30-2014
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Social resources can buffer against psychological distress following potentially traumatic events. Psychological distress can also lead to social resource deterioration. This longitudinal study evaluated whether baseline psychological distress symptoms and changes in these symptoms were associated with changes in social resources 5 months later among 96 adult male (52.6%) and female treatment-seeking torture survivors residing in Kurdistan, Iraq. Adapted versions of the Hopkins Symptom Checklist-25, Harvard Trauma Questionnaire, and a traumatic grief measure were used. Locally derived scales measured perceived social support, social integration, and frequency of social contact. Multinomial logistic regression models assessed the association between symptoms and loss or gain in social resources. We hypothesized that higher mental health symptoms would relate to decreased social resources. Higher baseline depression (adjusted conditional odds ratio [ACOR] = 1.14), posttraumatic stress disorder (PTSD; ACOR = 1.09), and traumatic grief symptoms (ACOR = 1.14) increased the odds of loss of social integration. For some, higher traumatic grief symptoms were associated with increased social integration (ACOR = 1.17). Increased anxiety (ACOR = 1.23) and PTSD symptoms (ACOR = 1.07) was associated with declines in social contact; decreased depression (ACOR = 1.06) and PTSD symptoms (ACOR = 1.04) were related to gaining social contact. This study highlights the complex relationship between mental health symptoms and losses and gains in social resources among torture survivors.
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The effect of cognitive therapy on structural social capital: results from a randomized controlled trial among sexual violence survivors in the Democratic Republic of the Congo.
Am J Public Health
PUBLISHED: 07-17-2014
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We evaluated changes in social capital following group-based cognitive processing therapy (CPT) for female survivors of sexual violence.
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The importance of establishing reliability and validity of assessment instruments for mental health problems: An example from Somali children and adolescents living in three refugee camps in Ethiopia.
Psychol Inj Law
PUBLISHED: 06-24-2014
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Assessing mental health problems cross-culturally for children exposed to war and violence presents a number of unique challenges. One of the most important issues is the lack of validated symptom measures to assess these problems. The present study sought to evaluate the psychometric properties of two measures to assess mental health problems: the Achenbach Youth Self-Report and the Child Posttraumatic Stress Disorder Symptom Scale. We conducted a validity study in three refugee camps in Eastern Ethiopia in the outskirts of Jijiga, the capital of the Somali region. A total of 147 child and caregiver pairs were assessed, and scores obtained were submitted to rigorous psychometric evaluation. Excellent internal consistency reliability was obtained for symptom measures for children and their caregivers. Validation of study instruments based on local case definitions was obtained for the caregivers but not consistently for the children. Sensitivity and specificity of study measures were generally low, indicating that these scales would not perform adequately as screening instruments. Combined test-retest and inter-rater reliability was low for all scales. This study illustrates the need for validation and testing of existing measures cross-culturally. Methodological implications for future cross-cultural research studies in low- and middle-income countries are discussed.
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Characterizing the developmental transcriptome of the oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae) through comparative genomic analysis with Drosophila melanogaster utilizing modENCODE datasets.
BMC Genomics
PUBLISHED: 05-28-2014
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The oriental fruit fly, Bactrocera dorsalis, is an important pest of fruit and vegetable crops throughout Asia, and is considered a high risk pest for establishment in the mainland United States. It is a member of the family Tephritidae, which are the most agriculturally important family of flies, and can be considered an out-group to well-studied members of the family Drosophilidae. Despite their importance as pests and their relatedness to Drosophila, little information is present on B. dorsalis transcripts and proteins. The objective of this paper is to comprehensively characterize the transcripts present throughout the life history of B. dorsalis and functionally annotate and analyse these transcripts relative to the presence, expression, and function of orthologous sequences present in Drosophila melanogaster.
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Loss of social resources predicts incident posttraumatic stress disorder during ongoing political violence within the Palestinian Authority.
Soc Psychiatry Psychiatr Epidemiol
PUBLISHED: 05-19-2014
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Exposure to ongoing political violence and stressful conditions increases the risk of posttraumatic stress disorder (PTSD) in low-resource contexts. However, much of our understanding of the determinants of PTSD in these contexts comes from cross-sectional data. Longitudinal studies that examine factors associated with incident PTSD may be useful to the development of effective prevention interventions and the identification of those who may be most at-risk for the disorder.
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A computer model of insect traps in a landscape.
Sci Rep
PUBLISHED: 05-16-2014
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Attractant-based trap networks are important elements of invasive insect detection, pest control, and basic research programs. We present a landscape-level, spatially explicit model of trap networks, focused on detection, that incorporates variable attractiveness of traps and a movement model for insect dispersion. We describe the model and validate its behavior using field trap data on networks targeting two species, Ceratitis capitata and Anoplophora glabripennis. Our model will assist efforts to optimize trap networks by 1) introducing an accessible and realistic mathematical characterization of the operation of a single trap that lends itself easily to parametrization via field experiments and 2) allowing direct quantification and comparison of sensitivity between trap networks. Results from the two case studies indicate that the relationship between number of traps and their spatial distribution and capture probability under the model is qualitatively dependent on the attractiveness of the traps, a result with important practical consequences.
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Suprabasal spread of melanocytes in dysplastic nevi and melanoma in situ: Ki-67-labeling rate of junctional melanocytes and suprabasal cells may be a helpful clue to the diagnosis.
Am. J. Surg. Pathol.
PUBLISHED: 05-09-2014
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Multiple criteria on routinely stained sections allow one to make a diagnosis of a dysplastic or "Clark" nevus (CN) versus melanoma in situ (MIS), and one of these is suprabasal spread of melanocytes. The extent of suprabasal spread of melanocytes in otherwise conventional CN and the combination of a sensitive marker of melanocytes combined with Ki-67 to assess the differences between the proliferation of melanocytes at the junction and those above it have not yet been studied. Fifty classic examples of CN and 27 cases of MIS were culled from the files of a university-based dermatopathology practice. All cases were stained with a 2-color method (MART-1/tyrosinase red, Ki-67 brown) to evaluate morphologic and immunohistochemical differences in these lesions. Fifteen of 50 cases of benign CN demonstrated suprabasal spread compared with 27 of 27 cases of MIS. The majority of CNs with suprabasal spread (13 of 15) showed a 0% Ki-67-labeling rate among the suprabasal melanocytes, and the majority of MISs (23 of 27) showed a 20% or greater Ki-67-labeling rate in suprabasal cells. Suprabasal melanocytes can be seen by immunostaining in otherwise unremarkable CN, wherein they are not notable in routinely stained sections, but their proliferation rate is much less than in MIS.
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Improving health services for African migrants in China: A health diplomacy perspective.
Glob Public Health
PUBLISHED: 05-07-2014
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Global health has become an increasingly prominent component of foreign policy in the last decade. The term health diplomacy has been used to describe this growing interface between foreign policy and global health, and it encompasses both the concept of using health to further foreign policy objectives as well as the idea that diplomatic tools can be helpful for attaining public health goals. The Chinese presence in Africa has grown in the last 15 years, generating increased interest in Sino-African relations. While much has been written in recent years about the Chinese presence in Africa, the growing numbers of Africans in China have attracted considerably less attention. Many are small-scale traders and might be expected to face many of the health challenges common among foreign migrants, but their health needs have been largely unrecognised. In this paper, we consider how a health diplomacy approach could be applied to African migrants in China, and the potential advantages and limitations of this strategy. We identify areas of overlap between public health, trade and foreign policy goals that can be emphasised to generate support for improved services for African migrants in China and to engage partners from a diversity of sectors.
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Regular drinking may strengthen the beneficial influence of social support on depression: findings from a representative Israeli sample during a period of war and terrorism.
Drug Alcohol Depend
PUBLISHED: 04-15-2014
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Social support is consistently associated with reduced risk of depression. Few studies have investigated how this relationship may be modified by alcohol use, the effects of which may be particularly relevant in traumatized populations in which rates of alcohol use are known to be high.
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Understanding resilience in armed conflict: social resources and mental health of children in Burundi.
Soc Sci Med
PUBLISHED: 02-20-2014
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Little is known about the role of cognitive social capital among war-affected youth in low- and middle-income countries. We examined the longitudinal association between cognitive social capital and mental health (depression and posttraumatic stress disorder (PTSD) symptoms), functioning, and received social support of children in Burundi. Data were obtained from face-to-face interviews with 176 children over three measurement occasions over the span of 4-months. Cognitive social capital measured the degree to which children believed their community was trustworthy and cohesive. Mental health measures included the Depression Self-Rating Scale (DSRS) (Birleson, 1981), the Child Posttraumatic Symptom Scale (Foa et al., 2001), and a locally constructed scale of functional impairment. Children reported received social support by listing whether they received different types of social support from self-selected key individuals. Cross-lagged path analytic modeling evaluated relationships between cognitive social capital, symptoms and received support separately over baseline (T1), 6-week follow-up (T2), and 4-month follow-up (T3). Each concept was treated and analyzed as a continuous score using manifest indicators. Significant associations between study variables were unidirectional. Cognitive social capital was associated with decreased depression between T1 and T2 (B = -.22, p < .001) and T2 and T3 (? = -.25, p < .001), and with functional impairment between T1 and T2 (? = -.15, p = .005) and T2 and T3 (? = -.14, p = .005); no association was found for PTSD symptoms at either time point. Cognitive social capital was associated with increased social support between T1 and T2 (? = .16, p = .002) and T2 and T3 (? = .16, p = .002). In this longitudinal study, cognitive social capital was related to a declining trajectory of children's mental health problems and increases in social support. Interventions that improve community relations in war-affected communities may alter the trajectories of resource loss and gain with conflict-affected children.
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A genomic perspective to assessing quality of mass-reared SIT flies used in Mediterranean fruit fly (Ceratitis capitata) eradication in California.
BMC Genomics
PUBLISHED: 01-31-2014
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Temperature sensitive lethal (tsl) mutants of the tephritid C. capitata are used extensively in control programs involving sterile insect technique in California. These flies are artificially reared and treated with ionizing radiation to render males sterile for further release en masse into the field to compete with wild males and disrupt establishment of invasive populations. Recent research suggests establishment of C. capitata in California, despite the fact that over 250 million sterile flies are released weekly as part of the state's preventative program. In this project, genome-level quality assessment was performed, measured as expression differences between the Vienna-7 tsl mutants used in SIT programs and wild flies. RNA-seq was performed to provide a genome-wide map of the messenger RNA populations in C. capitata, and to investigate significant expression changes in Vienna-7 mass reared flies.
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Summarizing craniofacial genetics and developmental biology (SCGDB).
Am. J. Med. Genet. A
PUBLISHED: 01-30-2014
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This overview article highlights active areas of research in craniofacial genetics and developmental biology as reflected in presentations given at the 34th annual meeting of the Society of Craniofacial Genetics and Developmental Biology (SCGDB) in Montreal, Quebec on October 11, 2011. This 1-day meeting provided a stimulating occasion that demonstrated the present status of research in craniofacial genetics and developmental biology and where the field is heading. To accompany the abstracts published in this issue I have selected several themes that emerged from the meeting. After discussing the basis on which craniofacial defects/syndromes are classified and investigated, I address the multi-gene basis of craniofacial syndromes with an examination of the roles of Sox9 and FGF receptors in normal and abnormal craniofacial development. I then turn to the knowledge being gained from population-wide and longitudinal cohort studies and from the discovery of new signaling centers that regulate craniofacial development.
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Exploring the activated adipogenic niche: interactions of macrophages and adipocyte progenitors.
Cell Cycle
PUBLISHED: 01-06-2014
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Adult adipose tissue contains a large supply of progenitors that can renew fat cells for homeostatic tissue maintenance and adaptive growth or regeneration in response to external challenges. However, the in vivo mechanisms that control adipocyte progenitor behavior are poorly characterized. We recently demonstrated that recruitment of adipocyte progenitors by macrophages is a central feature of adipose tissue remodeling under various adipogenic conditions. Catabolic remodeling of white adipose tissue by ?3-adrenergic receptor stimulation requires anti-inflammatory M2-polarized macrophages to clear dying adipocytes and to recruit new brown adipocytes from progenitors. In this Extra Views article, we discuss in greater detail the cellular elements of adipogenic niches and report a strategy to isolate and characterize the subpopulations of macrophages and adipocyte progenitors that actively participate in adrenergic tissue remodeling. Further characterization of these subpopulations may facilitate identification of new cellular targets to improve metabolic and immune function of adipose tissue.
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Fine-needle aspiration cytology for the diagnosis of metastatic melanoma: systematic review and meta-analysis.
Am. J. Clin. Pathol.
PUBLISHED: 10-15-2013
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To perform a thorough review and meta-analysis of studies that have shown non-image-guided fine-needle aspiration cytology (FNAC) to be highly sensitive and specific for assessing questionable metastatic melanoma to lymph nodes.
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Forty days after the Great East Japan Earthquake: field research investigating community engagement and traumatic stress screening in a post-disaster community mental health training.
Int J Psychiatry Med
PUBLISHED: 08-28-2013
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The current article describes the results of posttraumatic stress educational outreach and screening offered to 141 citizens of Japan who attended a public-service mental health training regarding post-disaster coping 40 days after a 6.8 Richter Scale earthquake, local and regional deaths, and an ongoing nuclear radiation threat. Attendees were given access to anonymous questionnaires that were integrated into the training as a tool to help enhance mental health literacy and bridge communication gaps. Questionnaires were turned in by a third of those in attendance. Among respondents, multiple exposures to potentially-traumatic events were common. More than a quarter of respondents met criteria for probable PTSD. Physical health and loss of sense of community were related to PTSD symptoms. Associations and diagnosis rates represented in these data are not generalizable to the population as a whole or intended for epidemiological purposes; rather, they are evidence of a potentially useful approach to post-disaster clinical screening, education, and engagement. Results are presented in the context of previous findings in Japan and ecologically-supportive post-disaster field research is discussed.
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Atypical intradermal smooth muscle neoplasms (formerly cutaneous leiomyosarcomas): case series, immunohistochemical profile and review of the literature.
Appl. Immunohistochem. Mol. Morphol.
PUBLISHED: 07-31-2013
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Atypical intradermal smooth muscle neoplasms (AISMN, formerly known as cutaneous leiomyosarcomas) are uncommon neoplasms, which seem to be remarkable for their excellent prognosis in contrast to their deeper counterparts. The rarity of AISMN has posed a challenge for characterizing the morphologic spectrum, immunohistochemical staining pattern, and behavior. In this study we evaluated the histologic and immunohistochemical features of 20 cases of AISMN. Clinical follow-up was available on 19 out of 20 patients and ranged from 1 to 124 months with an average of 35 months and a median of 20 months with a male predominance (male to female ratio was 2.3:1). Our data show a wide variation in differentiation and atypical features. Among these, the presence of mitotic figures is diagnostically valuable in rendering the final diagnosis. A broad panel of immunohistochemical stains revealed that smooth muscle actin and muscle specific actin, when used in combination, identified smooth muscle differentiation in 100% of the cases. With some caveats, CD34, S100, and CK 5/6 were helpful in ruling out other important cutaneous spindle cell neoplasms. Significantly, loss of phosphatase and tensin homolog (PTEN) staining was seen in the majority of our cases (80%), supporting a role for PTEN loss in the etiology of these lesions. Logistic regression analysis revealed that positive margin status was helpful for predicting recurrence (100% sensitivity and 94% specificity). We conclude that AISMN can have significant morphologic variation and overlap with other spindle cell neoplasms of the skin and that a limited panel of key immunohistochemical stains should be used to distinguish this lesion. The different surgical measures such as wide excision versus Mohs procedure showed a similar clinical outcome. Although the significance of frequent PTEN loss supports a molecular mechanism of tumor genesis, the diagnostic utility of the stain remains to be determined.
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Examining the Binge Eating Scale in screening for binge eating disorder in bariatric surgery candidates.
Obes Surg
PUBLISHED: 07-03-2013
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This study assessed the utility of the Binge Eating Scale (BES) as a measure of binge eating disorder (BED) in a bariatric surgery-seeking population by (a) determining the optimal BES cut score for predicting BED, (b) calculating concordance statistics, and (c) determining the predictive value of each BES item.
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Post-traumatic lingual artery pseudoaneurysm treated with ultrasound-guided percutaneous thrombin injection.
Ann Vasc Surg
PUBLISHED: 06-28-2013
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Pseudoaneurysms of the lingual artery are extremely rare and are commonly iatrogenic in nature or less frequently a result of blunt or penetrating trauma. Traditionally, these vascular abnormalities have been repaired with open or endovascular techniques. Although ultrasound-guided percutaneous thrombin injection has become standard treatment of superficial pseudoaneurysms, there are no reports of this being used in the treatment of lingual artery pseudoaneurysms. We report the case of a 26-year-old male who suffered a penetrating head and neck injury after an improvised explosive device blast in Iraq who presented with persistent oropharyngeal swelling. Color-flow Doppler revealed the classic "yin/yang" sign of a pseudoaneurysm and a computed tomography scan was obtained which demonstrated a right lingual artery pseudoaneurysm. With lack of endovascular capabilities and excessive risk of open surgery, thrombin was injected under ultrasound-guidance directly into the pseudoaneurysm. Computed tomography scan and Doppler ultrasound confirmed complete resolution of the aneurysm. This article presents the first reported case in English literature of a lingual artery aneurysm after penetrating trauma managed successfully with ultrasound-guided percutaneous thrombin injection.
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Sleep Disturbances Predict Later Trauma-Related Distress: Cross-Panel Investigation Amidst Violent Turmoil.
Health Psychol
PUBLISHED: 05-13-2013
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Objective: Sleep disturbances, including trouble falling and remaining asleep and recurrent nightmares, are symptoms of posttraumatic stress. A growing body of literature indicates that sleep disturbance may also convey vulnerability for the continuation of other symptoms of posttraumatic stress, including fear, anxiety, and heightened arousal. However, longitudinal research, which could help understand how these relationships unfold over time, has been limited. Method: The longitudinal relationships between sleep disturbance and posttraumatic stress were investigated in 779 Palestinian adults randomly selected and interviewed twice during the period from April 2008 to November 2008, amid ongoing violent political turmoil. The recruitment method produced a representative sample and excellent retention. Cross-panel structural equation modeling was used to examine relationships between sleep and distress across two study periods. Results: Results indicated that initial sleep problems were associated with increased posttraumatic stress disorder (PTSD), depression, and intrapersonal resource loss at follow-up 6 months later, but initial PTSD, depression, and intrapersonal resource loss were not associated with increased sleep problems at follow-up. Conclusions: Sleep problems may confer vulnerability to longer-term distress in the presence of ongoing political violence. Future research should examine whether interventions targeting trauma-related sleep problems may improve prevention and treatment for PTSD and related disorders. (PsycINFO Database Record (c) 2013 APA, all rights reserved).
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Risk-benefit analysis of sampling methods for fine-needle aspiration cytology: a mathematical modeling approach.
Am. J. Clin. Pathol.
PUBLISHED: 02-23-2013
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The effectiveness of fine-needle aspiration (FNA) increases with the number of needle passes, but needle passes are also associated with increased risk of adverse events. The trade-off between needle passes and adequacy has not been well characterized. Clinical studies are limited because of their inherent variability and limited sample size. We developed mathematical models to compare the performance of a variety of sampling protocols under a wide range of conditions. Specifically, we compared the performance of sampling methods using a fixed number of needle passes with sampling methods using a rapid onsite evaluation (ROSE) with a variable number of needle passes. Variable sampling with ROSE generally required fewer needle passes than fixed sample size policies to achieve a desired adequacy rate. Variable sampling policies using ROSE achieve greater per-case adequacy with fewer needle passes than sampling policies using a fixed number of passes if assessor accuracy is high.
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Small-molecule suppressors of Candida albicans biofilm formation synergistically enhance the antifungal activity of amphotericin B against clinical Candida isolates.
ACS Chem. Biol.
PUBLISHED: 02-14-2013
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A new class of fungal biofilm inhibitors represented by shearinines D (3) and E (4) were obtained from a Penicillium sp. isolate. The inhibitory activities of 3 and 4 were characterized using a new imaging flow-cytometer technique, which enabled the rapid phenotypic analysis of Candida albicans cell types (budding yeast cells, germ tube cells, pseudohyphae, and hyphae) in biofilm populations. The results were confirmed by experimental data obtained from three-dimensional confocal laser scanning microscopy and 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assays. These data indicate that 3 and 4 inhibited C. albicans biofilm formation by blocking the outgrowth of hyphae at a relatively late stage of biofilm development (IC50 = 8.5 and 7.6 ?M, respectively). However, 3 and 4 demonstrated comparatively weak activity at disrupting existing biofilms. Compounds 3 and 4 also exhibited synergistic activities with amphotericin B against C. albicans and other clinical Candida isolates by enhancing the potency of amphotericin B up to 8-fold against cells in both developing and established biofilms. These data suggest that the Candida biofilm disruption and amphotericin B potentiating effects of 3 and 4 could be mediated through multiple biological targets. The shearinines are good tools for testing the potential advantages of using adjunctive therapies in combination with antifungals.
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The association between posttraumatic stress symptoms and functional impairment during ongoing conflict in the Democratic Republic of Congo.
J Anxiety Disord
PUBLISHED: 01-25-2013
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The Democratic Republic of Congo (DRC) has suffered from a bloody conflict for more than a decade. More than 5,400,000 people died from war-related causes since 1998 and exposure to violence was wide-spread. This study investigated the impact of posttraumatic stress disorder (PTSD) symptoms on perceived health and physical and social functioning, filling an important gap in the current literature. Data were collected from a sample of 93 adults living in Bunia, Eastern Democratic Republic of Congo. Structured in-person interviews included the PTSD section of the Composite International Diagnostic Interview and the World Health Organization Disability Assessment Scale. Additional questions were included to assess social resources. Study recruitment was balanced to achieve equal representation of both sexes and each quarter of town. Forty percent met symptom criteria for probable PTSD. Individuals with PTSD reported poor perceived general health and had high disability scores compared to those without PTSD. Of the three PTSD symptom clusters, hyperarousal was most strongly associated with disability. Individuals with PTSD were significantly more emotionally affected by their health problems than those without PTSD (85% versus 41%), had more difficulties in activities involving social contact (54% versus 16%) and in doing their daily work (54% versus 20%). The impact of war-related violence on mental health is severe in the DRC. Psychosocial interventions developed in conflict areas might be best targeted primarily to supporting social functioning and reducing hyperarousal. Implications for clinical treatment and future directions are discussed.
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Secondary cartilage revealed in a non-avian dinosaur embryo.
PLoS ONE
PUBLISHED: 01-17-2013
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The skull and jaws of extant birds possess secondary cartilage, a tissue that arises after bone formation during embryonic development at articulations, ligamentous and muscular insertions. Using histological analysis, we discovered secondary cartilage in a non-avian dinosaur embryo, Hypacrosaurus stebingeri (Ornithischia, Lambeosaurinae). This finding extends our previous report of secondary cartilage in post-hatching specimens of the same dinosaur species. It provides the first information on the ontogeny of avian and dinosaurian secondary cartilages, and further stresses their developmental similarities. Secondary cartilage was found in an embryonic dentary within a tooth socket where it is hypothesized to have arisen due to mechanical stresses generated during tooth formation. Two patterns were discerned: secondary cartilage is more restricted in location in this Hypacrosaurus embryo, than it is in Hypacrosaurus post-hatchlings; secondary cartilage occurs at far more sites in bird embryos and nestlings than in Hypacrosaurus. This suggests an increase in the number of sites of secondary cartilage during the evolution of birds. We hypothesize that secondary cartilage provided advantages in the fine manipulation of food and was selected over other types of tissues/articulations during the evolution of the highly specialized avian beak from the jaws of their dinosaurian ancestors.
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Predictors of continued HIV-risk behaviors among drug users in methadone maintenance therapy program in China--a prospective study.
Harm Reduct J
PUBLISHED: 01-06-2013
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To examine the predictors of continued drug- and sex-related HIV-risk behaviors among drug users in methadone maintenance therapy (MMT) programs in China.
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Reciprocal relationships between resource loss and psychological distress following exposure to political violence: an empirical investigation of COR theorys loss spirals.
Anxiety Stress Coping
PUBLISHED: 11-18-2011
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We conducted a four-wave prospective study of Palestinian adults living in the West Bank, Gaza Strip, and East Jerusalem, interviewed between 2007 and 2009 at 6-month interval to explore transactional relationships between resource loss (i.e., intra and interpersonal resource loss) and psychological distress (i.e., posttraumatic stress disorder and depression symptoms). Initially, 1196 Palestinians completed the first wave interview and 752 of these participants completed all four interviews. A cross-lagged panel design was constructed to model the effects of trauma exposure on both resource loss and psychological distress and the subsequent reciprocal effects of resource loss and psychological distress across four time waves. Specifically, resource loss was modeled to predict distress, which in turn was expected to predict further resource loss. Structural equation modeling was used to test this design. We found that psychological distress significantly predicts resource loss across shorter, 6-month time waves, but that resource loss predicts distress across longer, 12-month intervals. These findings support the Conservation of Resources theorys corollary of loss spirals.
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A systematic review and meta-analysis of the diagnostic accuracy of frozen section for parotid gland lesions.
Am. J. Clin. Pathol.
PUBLISHED: 10-28-2011
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We conducted a systematic literature review using MEDLINE and Embase to identify articles on diagnostic accuracy of frozen section (FS) for salivary gland lesions published between January 1, 1985, and December 31, 2010. We also reviewed the reference lists of all identified articles and conducted a forward search using Scopus to identify all articles citing the reference set. Meta-analysis was used to produce a summary receiver operating characteristic (SROC) curve from which summary estimates of sensitivity and specificity were obtained. Study quality was assessed using the Quality of Diagnostic Accuracy Study (QUADAS) survey. The accuracy of FS was compared with that of fine-needle aspiration cytology using results from an earlier review. A set of 13 studies (1,880 cases) with extractable data met our inclusion criteria. The summary estimates for the area under the SROC curve, FS sensitivity, and FS specificity are 0.99 (95% confidence interval [CI], 0.98-1.00), 0.90 (95% CI, 0.81-0.94), and 0.99 (95% CI, 0.98-1.00), respectively. FS has acceptable accuracy (90% sensitivity, 99% specificity) and is consistently accurate across study centers.
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A systematic review and meta-analysis of the diagnostic accuracy of ultrasound-guided core needle biopsy for salivary gland lesions.
Am. J. Clin. Pathol.
PUBLISHED: 09-16-2011
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Core needle biopsy (CNB) of salivary gland lesions is a relatively new technique that may offer benefits for diagnosis of the lesions. We conducted a systematic literature review to identify studies published between January 1, 1985, and March 15, 2011. Summary estimates of sensitivity and specificity were obtained by using a summary receiver-operating characteristic (SROC) curve. Study quality was assessed by using the QUADAS survey. We identified 5 studies (277 cases) for inclusion. The area under the SROC for CNB was 1.00 (95% confidence interval [CI], 0.99-1.00). Based on histologically verified cases, the sensitivity of CNB is 0.92 (95% CI, 0.77-0.98) and the specificity is 1.00 (95% CI, 0.76-1.00). We conclude that CNB has high accuracy and a low (1.2%) inadequacy rate. CNB is more accurate than fine-needle aspiration, at least in some settings, but the best selection of which test to use for an individual patient and setting remains to be defined.
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Lactation defect with impaired secretory activation in AEBP1-null mice.
PLoS ONE
PUBLISHED: 07-18-2011
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Adipocyte enhancer binding protein 1 (AEBP1) is a multifunctional protein that negatively regulates the tumor suppressor PTEN and I?B?, the inhibitor of NF-?B, through protein-protein interaction, thereby promoting cell survival and inflammation. Mice homozygous for a disrupted AEBP1 gene developed to term but showed defects in growth after birth. AEBP1(-/-) females display lactation defect, which results in the death of 100% of the litters nursed by AEBP1(-/-) dams. Mammary gland development during pregnancy appears normal in AEBP1(-/-) dams; however these mice exhibit expansion of the luminal space and the appearance of large cytoplasmic lipid droplets (CLDs) in the mammary epithelial cells at late pregnancy and parturition, which is a clear sign of failed secretory activation, and accumulation of milk proteins in the mammary gland, presumably reflecting milk stasis following failed secretory activation. Eventually, AEBP1(-/-) mammary gland rapidly undergoes involution at postpartum. Stromal restoration of AEBP1 expression by transplanting wild-type bone marrow (BM) cells is sufficient to rescue the mammary gland defect. Our studies suggest that AEBP1 is critical in the maintenance of normal tissue architecture and function of the mammary gland tissue and controls stromal-epithelial crosstalk in mammary gland development.
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Traumatic noncombat-related hand injuries in U.S. troops in the combat zone.
Mil Med
PUBLISHED: 06-28-2011
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The epidemiology of traumatic, nonbattle, Combat Zone hand injuries has not been well explored.
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A systematic review and meta-analysis of the diagnostic accuracy of fine-needle aspiration cytology for parotid gland lesions.
Am. J. Clin. Pathol.
PUBLISHED: 06-21-2011
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The clinical usefulness of fine-needle aspiration cytology (FNAC) for the diagnosis of parotid gland lesions is controversial. Many accuracy studies have been published, but the literature has not been adequately summarized. We identified 64 studies on the diagnosis of malignancy (6,169 cases) and 7 studies on the diagnosis of neoplasia (795 cases). The diagnosis of neoplasia (area under the summary receiver operating characteristic [AUSROC] curve, 0.99; 95% confidence interval [CI], 0.97-1.00) had higher accuracy than the diagnosis of malignancy (AUSROC, 0.96; 95% CI, 0.94-0.97). Several sources of bias were identified that could affect study estimates. Studies on the diagnosis of malignancy showed significant heterogeneity (P < .001). The subgroups of American, French, and Turkish studies showed greater homogeneity, but the accuracy of these subgroups was not significantly different from that of the remaining subgroup. It is not possible to provide a general guideline on the clinical usefulness of FNAC for parotid gland lesions owing to the variability in study results. There is a need to improve the quality of reporting and to improve study designs to remove or assess the impact of bias.
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A novel role for the NLRC4 inflammasome in mucosal defenses against the fungal pathogen Candida albicans.
PLoS Pathog.
PUBLISHED: 05-10-2011
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Candida sp. are opportunistic fungal pathogens that colonize the skin and oral cavity and, when overgrown under permissive conditions, cause inflammation and disease. Previously, we identified a central role for the NLRP3 inflammasome in regulating IL-1? production and resistance to dissemination from oral infection with Candida albicans. Here we show that mucosal expression of NLRP3 and NLRC4 is induced by Candida infection, and up-regulation of these molecules is impaired in NLRP3 and NLRC4 deficient mice. Additionally, we reveal a role for the NLRC4 inflammasome in anti-fungal defenses. NLRC4 is important for control of mucosal Candida infection and impacts inflammatory cell recruitment to infected tissues, as well as protects against systemic dissemination of infection. Deficiency in either NLRC4 or NLRP3 results in severely attenuated pro-inflammatory and antimicrobial peptide responses in the oral cavity. Using bone marrow chimeric mouse models, we show that, in contrast to NLRP3 which limits the severity of infection when present in either the hematopoietic or stromal compartments, NLRC4 plays an important role in limiting mucosal candidiasis when functioning at the level of the mucosal stroma. Collectively, these studies reveal the tissue specific roles of the NLRP3 and NLRC4 inflammasome in innate immune responses against mucosal Candida infection.
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Intracellular invasion of green algae in a salamander host.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 04-04-2011
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The association between embryos of the spotted salamander (Ambystoma maculatum) and green algae ("Oophila amblystomatis" Lamber ex Printz) has been considered an ectosymbiotic mutualism. We show here, however, that this symbiosis is more intimate than previously reported. A combination of imaging and algal 18S rDNA amplification reveals algal invasion of embryonic salamander tissues and cells during development. Algal cells are detectable from embryonic and larval Stages 26-44 through chlorophyll autofluorescence and algal 18S rDNA amplification. Algal cell ultrastructure indicates both degradation and putative encystment during the process of tissue and cellular invasion. Fewer algal cells were detected in later-stage larvae through FISH, suggesting that the decline in autofluorescent cells is primarily due to algal cell death within the host. However, early embryonic egg capsules also contained encysted algal cells on the inner capsule wall, and algal 18S rDNA was amplified from adult reproductive tracts, consistent with oviductal transmission of algae from one salamander generation to the next. The invasion of algae into salamander host tissues and cells represents a unique association between a vertebrate and a eukaryotic alga, with implications for research into cell-cell recognition, possible exchange of metabolites or DNA, and potential congruence between host and symbiont population structures.
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Phytobezoar as a cause of intestinal obstruction.
J. Gastrointest. Surg.
PUBLISHED: 03-16-2011
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A small bowel phytobezoar is a rare cause of intestinal obstruction, whose most common cause is adhesion.
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Are community studies of psychological traumas impact accurate? A study among Jews and Palestinians.
Psychol Assess
PUBLISHED: 03-09-2011
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We evaluated the accuracy of posttraumatic stress disorder (PTSD) and major depression (MD) diagnoses using brief assessment instruments conducted by phone. PTSD and MD were assessed by telephone interview in a randomly selected sample of Jewish and Palestinian residents of Jerusalem (N = 150) during a period of marked threat of terrorism and war. We utilized the PTSD Symptom Scale Interview Format (Foa, Riggs, Dancu, & Rothbaum, 1993) and the Patient Health Questionnaire-9 (PHQ-9; Kroenke, Spitzer, & Williams, 2001). We then conducted in-depth, in-person interviews within 2 weeks, assessing PTSD and MD using the Composite International Diagnostic Interview (CIDI; Kessler et al., 2004). The prevalence of PTSD and MD diagnosis ascertained by the 2 assessment modalities was similar. Indices of classification accuracy for the phone interview, using the in-person interview as the standard, ranged from modest to high. Brief phone and in-depth in-person measures of PTSD and MD also correlated similarly with other demographic, stress, and coping factors, suggesting convergent validity. Brief phone interviews appear useful for estimating the prevalence of psychological disorders in mass casualty contexts and may have a critical role in both epidemiologic work and guiding public health interventions.
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The limits of resilience: distress following chronic political violence among Palestinians.
Soc Sci Med
PUBLISHED: 02-10-2011
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We examined posttraumatic stress disorder (PTSD) and depression symptom trajectories during ongoing exposure to political violence, seeking to identify psychologically resilient individuals and the factors that predict resilience. Face-to-face interviews were conducted with a random sample of 1196 Palestinian adult residents of the West Bank, Gaza, and East Jerusalem across three occasions, six months apart (September 2007-November 2008). Latent growth mixture modeling identified PTSD, and depression symptom trajectories. Results identified three PTSD trajectories: moderate-improving (73% moderate symptoms at baseline, improving over time), severe-chronic (23.2% severe and elevated symptoms over the entire year); and severe-improving (3.5% severe symptoms at baseline and marked improvement over time). Depression trajectories were moderate-improving (61.5%); severe-chronic (24.4%); severe-improving (14.4%). Predictors of relatively less severe initial symptom severity, and improvement over time for PTSD were less political violence exposure and less resource loss; and for depression were younger age, less political violence exposure, lower resource loss, and greater social support. Loss of psychosocial and material resources was associated with the level of distress experienced by participants at each time period, suggesting that resource-based interventions that target personal, social, and financial resources could benefit people exposed to chronic trauma.
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CD81 is essential for the re-entry of hematopoietic stem cells to quiescence following stress-induced proliferation via deactivation of the Akt pathway.
PLoS Biol.
PUBLISHED: 01-20-2011
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The regulatory mechanisms governing the cell cycle progression of hematopoietic stem cells (HSCs) are well characterized, but those responsible for the return of proliferating HSCs to a quiescent state remain largely unknown. Here, we present evidence that CD81, a tetraspanin molecule acutely responsive to proliferative stress, is essential for the maintenance of long-term repopulating HSCs. Cd81(-/-) HSCs showed a marked engraftment defect when transplanted into secondary recipient mice and a significantly delayed return to quiescence when stimulated to proliferate with 5-fluorouracil (5FU). In addition, we found that CD81 proteins form a polarized patch when HSCs are returning to quiescence. Thus, we propose that the spatial distribution of CD81 during the HSC recovery phase drives proliferative HSC to quiescence, and is important to preserve the self-renewal properties. Here, we show that lack of CD81 leads to loss of HSC self-renewal, and the clustering of CD81 on HSC membrane results in deactivation of Akt, which subsequently leads to nuclear translocation of FoxO1a. Thus, CD81 functions as part of a previously undefined mechanism that prohibits excessive proliferation of HSCs exposed to environmental stress.
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The Obsessive Compulsive Cocaine Scale: assessment of factor structure, reliability, and validity.
Addict Behav
PUBLISHED: 01-12-2011
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The present study assessed the factor structure, reliability, test retest, convergent validity, and predictive validity of the Obsessive Compulsive Cocaine Scale (OCCS), a newly developed questionnaire adapted from the Obsessive Compulsive Drinking Scale (OCDS). The questionnaire was administered to 189 cocaine-dependent individuals participating in two medication treatment trials for cocaine dependence. Confirmatory factor analysis of this measure revealed that it primarily assesses two factors, obsessions and compulsions. In addition, the data provided strong support for the internal consistency, test-retest reliability, predictive validity, and convergent validity of this two-factor measure. Overall, the data provide support for the psychometric strength of a modified version of the OCDS specifically designed to assess obsessive and compulsive cocaine use among those with cocaine dependence.
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Levels of biological organization and the origin of novelty.
J. Exp. Zool. B Mol. Dev. Evol.
PUBLISHED: 01-12-2011
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The concept of novelty in evolutionary biology pertains to multiple tiers of biological organization from behavioral and morphological changes to changes at the molecular level. Identifying novel features requires assessments of similarity (homology and homoplasy) of relationships (phylogenetic history) and of shared developmental and genetic pathways or networks. After a brief discussion of how novelty is used in recent literature, we discuss whether the evolutionary approach to homology and homoplasy initially formulated by Lankester in the 19th century informs our understanding of novelty today. We then discuss six examples of morphological features described in the recent literature as novelties, and assess the basis upon which they are regarded as novel. The six are: origin of the turtle shell, transition from fish fins to tetrapod limbs, origination of the neural crest and neural crest cells, cement glands in frogs and casquettes in fish, whale bone-eating tubeworms, and the digestion of plant proteins by nematodes. The article concludes with a discussion of means of acquiring novel genetic information that can account for novelty recognized at higher levels. These are co-options of existing genetic circuitry, gene duplication followed by neofunctionalization, gene rearrangements through mobile genetic elements, and lateral gene transfer. We conclude that on the molecular level only the latter category provides novel genetic information, in that there is no homologous precursor. However, novel phenotypes can be generated through both neofunctionalization and gene rearrangements. Therefore, assigning phenotypic or genotypic "novelty" is contingent on the level of biological organization addressed.
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Ultrasound diagnosis of a patellar tendon rupture.
Mil Med
PUBLISHED: 12-01-2010
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Many forward units are being deployed with portable ultrasound capability. We describe a case of a patient with a complete patellar tendon rupture that was diagnosed in the deployed environment using a portable ultrasound. Military physicians can benefit from sonographic evaluation of patients with musculoskeletal injuries in a deployed setting. The information they gain can assist them in giving better care to their patients and in making decisions on patient evacuation.
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Sociocultural domains of depression among indigenous populations in Latin America.
Int Rev Psychiatry
PUBLISHED: 09-30-2010
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Not enough research has been carried out on depression up to now in Latin America. The knowledge that has resulted from research activities in the USA or Europe offers limited generalizability to other regions of the world, including Latin America. In the Andean highlands of Ecuador, we found very high rates of moderate and severe depressive symptoms, a finding that must be interpreted within its cultural context. Somatic manifestations of depression predominated over cognitive manifestations, and higher education level was protective against depression. These findings call for an appreciation of culturally specific manifestations of depression and the social factors that influence them. These factors must be further studied in order to give them the deserved priority, allocate resources appropriately, and formulate innovative psychosocial interventions.
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Exposure to prolonged socio-political conflict and the risk of PTSD and depression among Palestinians.
Psychiatry
PUBLISHED: 09-17-2010
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Little is known about the impact of traumatic experiences and stressful life conditions on people in low-income countries who live in conditions of ongoing political violence. In order to determine the prevalence and predictors of post-traumatic stress disorder (PTSD) and major depression (MD) among Palestinians subjected to chronic political violence and upheaval, we used a stratified multi-stage cluster random sampling strategy to interview a representative sample of 1,200 Palestinian adults living in Gaza, the West Bank, and East Jerusalem. Prevalence of PTSD/MD for men living in the West Bank, Gaza, and East Jerusalem was 25.4%/29.9%, 22.6%/27.6%, and 16.1%/16.1%, respectively. For women, the prevalence of PTSD/MD was 23.8%/29.0%, 23.9%/28.9%, and 19.7%/27.6%. Among men, PTSD was significantly positively associated with age group, two or more incidences of political violence (compared to none), greater intrapersonal resource loss, and loss of faith in government. MD was positively associated with experiencing exposure to one, or two or more, incidences of political violence (compared to none), and greater interpersonal and intrapersonal resource loss. Among women, PTSD was positively associated with greater interpersonal and intrapersonal resource loss, and MD was positively associated with death of a loved one, two or more socio-political stressors (compared to none) previous to the past year, one or more socio-political stressors (compared to none) in the past year, and greater interpersonal and intrapersonal resource loss. Interpersonal and intrapersonal resource losses were consistently associated with PTSD and MD, suggesting potential targets for intervention and prevention efforts and thus provide important keys to treatment in areas of ongoing conflict.
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C1q deficiency leads to the defective suppression of IFN-alpha in response to nucleoprotein containing immune complexes.
J. Immunol.
PUBLISHED: 09-15-2010
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Almost all humans with homozygous deficiency of C1q develop systemic lupus erythematosus (SLE). The precise cellular mechanism(s) by which C1q prevents the development of SLE remains unclear. In this study, we tested the role of C1q in the regulation of IFN-? induced by immune complexes (ICs) in vitro, as well as the consequences of lack of C1q in vivo. Our experiments revealed that C1q preferentially promotes the binding of SLE ICs to monocytes rather than plasmacytoid dendritic cells, but this inhibition was not due to the induction of inhibitory soluble factors. The presence of C1q also altered the trafficking of ICs within monocytes such that ICs persisted in early endosomes. In patients with C1q deficiency, serum and cerebrospinal fluid levels of IFN-? and IFN-?-inducible protein-10 levels were elevated and strongly correlated with Ro autoantibodies, demonstrating the clinical significance of these observations. These studies therefore associate C1q deficiency with defective regulation of IFN-? and provide a better understanding of the cellular mechanisms by which C1q prevents the development of IC-stimulated autoimmunity.
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HSP90 expression in two migratory cell types during ascidian development: test cells deposit HSP90 on the larval tunic.
Int. J. Dev. Biol.
PUBLISHED: 08-17-2010
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Heat shock protein 90 (HSP90) is a ubiquitously expressed molecular chaperone that controls the folding, assembly and activity of proteins, many of which are involved in signal transduction. Recent work has shown that HSP90 is present extracellularly, indicating a heretofore under-appreciated requirement for extracellular chaperoning, particularly among migratory cells. We applied immunological and surgical techniques to document the differential expression of HSP90 during ascidian development. Relative to other cell types during development, test cells and trunk lateral cells (TLCs), two migratory cell types in the ascidian Boltenia villosa, express elevated levels of HSP90. Late in embryogenesis, test cells deposit HSP90 onto the tunic, the second report of extracellular HSP90 during animal development. The pyurid ascidian Halocynthia igaboja and the styelids Cnemidocarpa finmarkiensis and Botrylloides violaceus all express HSP90 at elevated levels in larval mesenchyme, suggesting that this pattern of expression is widespread in the Ascidiaceae. We show that HSP90 expression in TLCs and test cells is coincident with the presence of HNK-1. Whereas in B. violaceous, cell populations expressing elevated levels of HSP90 are distinct from those expressing HNK-1, in B. villosa both these antigens are present in the TLCs. We evaluate existing hypotheses about test cell function and, in reference to the similarities between test cells and some of the descendants of TLCs, hypothesize that test cells are TLC descendants. Implications for the proposed evolutionary relationship between TLCs and neural crest are briefly discussed.
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Macrophage activation differentially modulates particle binding, phagocytosis and downstream antimicrobial mechanisms.
Dev. Comp. Immunol.
PUBLISHED: 05-05-2010
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Phagocytosis provides a critical first line of defense against invading pathogens. Engagement of particles through receptor-mediated binding precedes internalization and induction of cellular antimicrobial responses. Phagocytes have the capacity to differentially regulate binding and internalization processes through changes in their receptor profile and modulation of downstream events. This is necessary for the intricate control of phagocytic antimicrobial responses. Several methods are available for evaluation of phagocytosis. Unfortunately, none allow for accurate quantitation of both binding and internalization events. To overcome these limitations, we have developed a novel phagocytosis assay based on a multi-spectral imaging flow cytometry platform. This assay discriminates between internalized and surface-bound particles in a statistically robust manner and allows multi-parametric analysis of phagocytosis and downstream anti-microbial responses. We also devised a novel approach for examination of phagolysosome fusion, which provides an improved capacity for quantitative assessment of phagolysosome fusion in mixed populations of intact cells. Importantly, our approaches are likely amenable to a broad range of comparative model systems based on our examination of murine RAW 264.7 cells and a goldfish primary kidney macrophage (PKM) model system. The latter allowed us to examine the evolutionary conservation of phagocytic antimicrobial responses in a lower vertebrate model. While it has been previously reported that mixed populations of these macrophage cultures are phagocytic, it remained unclear if sub-populations within them contributed differentially to this activity. In accordance with higher vertebrate models, we found that differentiation along the macrophage pathway leads to an increased capacity for phagocytosis in goldfish PKM. Interestingly, cellular activation differentially regulated particle internalization in PKM monocyte and mature macrophage subsets. We also found differential regulation of phagolysosome fusion and downstream production of reactive oxygen intermediates (ROI). The temporal activation of specific phagocytic antimicrobial responses at distinct stages of PKM differentiation suggests specialization within the macrophage compartment early in evolution, geared to meet specific host immunity requirements within specialized niches.
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Comparative development of the crocodylian interclavicle and avian furcula, with comments on the homology of dermal elements in the pectoral apparatus.
J. Exp. Zool. B Mol. Dev. Evol.
PUBLISHED: 04-28-2010
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The pectoral apparatus (shoulder girdle plus sternum) of amniotes plesiomorphically includes an unpaired element of dermal origin. In crocodylians, lepidosaurs, and nontherian synapsids (monotremes and their ancestors) this element is identified as the interclavicle, in Testudines (turtles and tortoises) as the entoplastron, and in Aves as the furcula. We investigated embryonic development of the interclavicle in Alligator mississippiensis (American alligator) and of the furcula in Gallus gallus (domestic chicken). The interclavicle and furcula are among the first skeletal elements to ossify, beginning at Ferguson stage 19 (Alligator) and Hamburger and Hamilton stage 33 (Gallus). Both elements: occupy a similar mid-ventral position within the pectoral apparatus; develop from paired (bilateral) cell condensations; never coexist at anytime during ontogeny or in the adult; and undergo intramembranous (i.e., direct) ossification. For both the interclavicle and the furcula, the initial onset of ossification is concomitant with mineralization of elements of the dermatocranium, and occurs in advance of mineralization of the replacement bones (e.g., scapula, metacoracoid) of the pectoral apparatus. Shortly after the initiation of ossification the paired condensations of both elements fuse. For each of Alligator and Gallus, only one pair of skeletogenic condensations is present during embryonic development. Based on these data and a review of the evolution and development of dermal elements in the pectoral apparatus, we conclude that the interclavicle is equally parsimonious as a homolog of the furcula.
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Skeletal advance and arrest in giant non-metamorphosing African clawed frog tadpoles (Xenopus laevis: Daudin).
J. Anat.
PUBLISHED: 04-21-2010
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This study examines the skeletons of giant non-metamorphosing (GNM) Xenopus laevis tadpoles, which arrest their development indefinitely before metamorphosis, and grow to excessively large sizes in the absence of detectable thyroid glands. Cartilage growth is isometric; however, chondrocyte size is smaller in GNM tadpoles than in controls. Most cartilages stain weakly with alcian blue, and several cartilages are calcified (unlike controls). However, cartilages subjacent to periosteum-derived bone retain strong affinities for alcian blue, indicating a role for periosteum-derived bone in the retention of glycosaminoglycans during protracted larval growth. Bone formation in the head, limb, and axial skeletons is advanced in comparison with stage-matched controls, but arrests at various mid-metamorphic states. Both dermal and periosteum-derived bones grow to disproportionately large sizes in comparison to controls. Additionally, mature monocuspid teeth form in several GNM tadpoles. Advances in skeletal development are attributable to the old ages and large sizes of these tadpoles, and reveal unexpected developmental potentials of the pre-metamorphic skeleton.
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Thermodynamics of peptide and non-peptide interactions with the human 5HT1a receptor.
Pharmacology
PUBLISHED: 03-30-2010
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The human serotonin 1a receptor (H5HT1aR) is a highly studied member of the 7 transmembrane G protein-coupled receptors. This model receptor, negatively coupled to adenylyl cyclase via Gi, is linked to physiological processes such as cognition and mood regulation and to associated disorders like anxiety and depression. Gibbs free energies, enthalpies, and entropies were calculated for the agonist [(3)H]8-OH-DPAT in the presence of synthetic peptides derived from sequences of intracellular loops 2 and 3 of the H5HT1aR. For comparative purposes, the thermodynamic parameters were also determined in the presence of a limited number of ligand-binding site substances (the partial agonist dipropyltryptamine [DPT], and the full agonist [(3)H]8-OH-DPAT alone). All of these thermodynamic measurements were based on binding data accumulated over a range of temperatures (0-35 degrees C). Representative examples of binding constant experiments and vant Hoff plots are shown to establish the thermodynamic variables. Although differences exist between the peptides themselves and the non-peptide agonists, in all situations the binding events are highly entropy driven. Differences between this information and published data for rat 5HT1aR are discussed, as are relationships to other receptor systems. Overall, the conclusions should be useful in further defining a comprehensive model of 5HT1aR, and for future development of binding-site and non-binding-site directed agents for the receptor.
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Conventional apoptosis assays using propidium iodide generate a significant number of false positives that prevent accurate assessment of cell death.
J. Immunol. Methods
PUBLISHED: 03-26-2010
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The advent of flow cytometry-based applications has significantly impacted the study of cellular apoptosis. Propidium iodide (PI) is a commonly used viability stain in these studies. Unfortunately, we find that conventional Annexin V/PI protocols lead to a significant number of false positive events (up to 40%), which are associated with PI staining of RNA within the cytoplasmic compartment. Both primary cells and cell lines are affected, with large cells (nuclear: cytoplasmic ratios <0.5) showing the highest occurrence. This distribution spans a wide range of animal models including mice, swine, avian, and teleost fish and potentially affects up to 1016 out of 1019 of peer-reviewed papers published in this area since 1995. We show that the primary ramifications from these findings relate to cells experiencing changes in RNA content. Virally infected cells, for example, are qualified as undergoing apoptosis in response to infection based on conventional staining protocols; in fact, these cells are alive and actively producing viral RNA that can serve to produce additional infectious viral particles. Based on our observations we propose a modified protocol, show that it overcomes previous drawbacks for this technique, and that it will allow for more accurate assessment of cell death across various platforms.
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Exploring the association between posttraumatic growth and PTSD: a national study of Jews and Arabs following the 2006 Israeli-Hezbollah war.
J. Nerv. Ment. Dis.
PUBLISHED: 03-11-2010
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Posttraumatic growth (PTG)-deriving benefits following potentially traumatic events-has become a topic of increasing interest. We examined factors that were related to self-reported PTG, and the relationship between PTG and symptoms of post-traumatic stress (PTS) following the 2006 Israel-Hezbollah. Drawing from a national random sample of Israel, data from 806 terrorism-exposed Israeli adults were analyzed. PTG was associated with being female, lower education, greater recent terrorism exposure, greater loss of psychosocial resources, greater social support, and greater self-efficacy. PTG was a consistent predictor of PTS across hierarchical linear regression models that tested whether demographic, stress, or personal resources moderated the relationship between PTG and PTS. PTG did not relate to PTS differently for people who differed by age, sex, ethnicity, education, religiosity, degree of terrorism exposure, self-efficacy, nonterrorism stressful life events, and loss of psychosocial and economic resources. PTG was not related to well-being for any of these subgroups.
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Somatic and cognitive domains of depression in an underserved region of Ecuador: some cultural considerations.
World Psychiatry
PUBLISHED: 10-09-2009
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Not enough research efforts on depression have been carried out up to now in Latin America. The knowledge that has resulted from research activities in the United States or Europe offers limited generalizability to other regions of the world, including Latin America. In the Andean highlands of Ecuador, we found very high rates of moderate and severe depressive symptoms, a finding that must be interpreted within its cultural context. Somatic manifestations of depression predominated over cognitive manifestations, and higher education level was protective against depression. These findings call for an appreciation of culturally-specific manifestations of depression and the social factors that influence them. These factors must be further studied in order to give them the deserved priority, allocate resources appropriately, and formulate innovative psychosocial interventions.
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Sniffing out new data and hypotheses on the form, function, and evolution of the echinopluteus post-oral vibratile lobe.
Biol. Bull.
PUBLISHED: 06-27-2009
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The performance requirements of ciliary band feeding explain the convoluted forms of many marine invertebrate larvae. Convolutions increase surface area and therefore feeding rates per unit body volume. We review recent advances in morphology, neural development, and behavior at settlement of the echinoid Lytechinus pictus and provide new ultrastructural and expression data on larvae of its congener, L. variegatus. Larvae of the echinometrid Colobocentrotus atratus contain neurons identified by their expression of nitric oxide synthase (NOS), indicating that this character is not unique to Lytechinus. We hypothesize that in some echinoids the convoluted shape of the post-oral vibratile lobe (POVL) covaries with the distribution of identified sensory neurons to enable olfaction during settlement. An analysis of variation in structural elaboration of the post-oral transverse ciliary band (PTB) within Echinoida and in feeding larvae of other echinoderm classes indicates that only echinoids, but not all echinoids, possess this novel character; larvae that do are distributed heterogeneously within the class. In recognition of this specialized function for the POVL and surrounding ectoderm, and because it is lobate and grows toward the mouth, we propose naming this structure the adoral lobe.
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Psychosocial correlates of binge eating in Hispanic, African American, and Caucasian women presenting for bariatric surgery.
Eat Behav
PUBLISHED: 05-27-2009
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Research suggests that that binge eating, stress, and depression are prevalent among individuals seeking bariatric surgery. However, ethnic differences in the prevalence of binge eating and binge eating disorder (BED) in this population remain unclear, as does the impact of depression and stress on any such relationship. Further, no studies to date have examined the prevalence of binge eating in Hispanic women presenting for bariatric surgery. This study sought to (a) compare the prevalence and severity of binge eating symptomatology and BED diagnosis in Hispanic, African American, and Caucasian women presenting for gastric bypass surgery, (b) examine the impact of depressive symptoms and stress on binge eating symptomatology, and (c) investigate whether ethnicity moderated any relationship between depression, stress, and binge eating. Results indicated that Hispanic women exhibited equal rates of binge eating symptomatology, BED, and depressive symptomatology as African American and Caucasian women. However, Caucasian women exhibited greater binge eating symptomatology than African American women, and African American women endorsed greater levels of stress than Caucasian women. Across all ethnic groups, depressive symptomatology, but not stress, significantly predicted binge eating severity. These findings suggest that Hispanic women presenting for bariatric surgery report binge eating rates equivalent to Caucasian and African American women, and that depressive symptoms are an important predictor of binge eating in female bariatric surgery candidates across ethnic groups.
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Regulation of LKB1/STRAD localization and function by E-cadherin.
Curr. Biol.
PUBLISHED: 04-30-2009
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LKB1 kinase is a tumor suppressor that is causally linked to Peutz-Jeghers syndrome. In complex with the pseudokinase STRAD and the scaffolding protein MO25, LKB1 phosphorylates and activates AMPK family kinases, which mediate many cellular processes. The prototypical family member AMPK regulates cell energy metabolism and epithelial apicobasal polarity. This latter event is also dependent on E-cadherin-mediated adherens junctions (AJs) at lateral borders. Strikingly, overexpression of LKB1/STRAD can also trigger establishment of epithelial polarity in the absence of cell-cell or cell-matrix contacts. However, the upstream factors that normally govern LKB1/STRAD function are unknown. Here we show by immunostaining and fluorescence resonance energy transfer that active LKB1/STRAD kinase complex colocalizes with E-cadherin at AJs. LKB1/STRAD localization and AMPK phosphorylation require E-cadherin-dependent maturation of AJs. However, LKB1/STRAD complex kinase activity is E-cadherin independent. These data suggest that in polarized epithelial cells, E-cadherin regulates AMPK phosphorylation by controlling the localization of the LKB1 complex. The LKB1 complex therefore appears to function downstream of E-cadherin in tumor suppression.
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An essential role for the NLRP3 inflammasome in host defense against the human fungal pathogen Candida albicans.
Cell Host Microbe
PUBLISHED: 04-11-2009
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Candida albicans is an opportunistic fungal pathogen causing life-threatening mucosal and systemic infections in immunocompromised humans. Using a murine model of mucosal Candida infection, we investigated the role of the proinflammatory cytokine IL-1beta in host defense to Candida albicans. We find that the synthesis, processing, and release of IL-1beta in response to Candida are tightly controlled and first require transcriptional induction, followed by a second signal leading to caspase-1-mediated cleavage of the pro-IL-1beta cytokine. The known fungal pattern recognition receptors TLR2 and Dectin-1 regulate IL-1beta gene transcription, whereas the NLRP3-containing proinflammatory multiprotein complex, the NLRP3 inflammasome, controls caspase-1-mediated cleavage of pro-IL-1beta. Furthermore, we show that TLR2, Dectin-1, and NLRP3 are essential for defense against dissemination of mucosal infection and mortality in vivo. Therefore, in addition to sensing bacterial and viral pathogens, the NLRP3 inflammasome senses fungal pathogens and is critical in host defense against Candida.
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Cartilage differentiation in cephalopod molluscs.
Zoology (Jena)
PUBLISHED: 03-17-2009
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Amongst the various metazoan lineages that possess cartilage, tissues most closely resembling vertebrate hyaline cartilage in histological section are those of cephalopod molluscs. Although elements of the adult skeleton have been described, the development of these cartilages has not. Using serial histology of sequential developmental stages of the European cuttlefish, Sepia officinalis, we investigate these skeletal elements and offer the first description of the formation of any cellular invertebrate cartilage. Our data reveal that cuttlefish cartilage most often differentiates from uncondensed mesenchymal cells near the end of embryonic development, but that the earliest-forming cartilages differentiate from a cellular condensation which goes through a protocartilage stage in a manner typical of vertebrate primary cartilage formation. We further investigate the distribution and degree of differentiation of cartilages at the time of hatching in an additional four cephalopod species. We find that the timing of cartilage development varies between elements within a single species, as well as between species. We identify a tendency towards cartilage differentiation from uncondensed connective tissue in elements that form at the end of embryogenesis or after hatching. These data suggest a form of metaplasia from connective tissue is the ancestral mode of cartilage formation in this lineage.
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Alpha6beta4 integrin crosslinking induces EGFR clustering and promotes EGF-mediated Rho activation in breast cancer.
J. Exp. Clin. Cancer Res.
PUBLISHED: 02-26-2009
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The alpha6beta4 integrin is overexpressed in the basal subtype of breast cancer and plays an important role in tumor cell motility and invasion. EGFR is also overexpressed in the basal subtype of breast cancer, and crosstalk between alpha6beta4 integrin and EGFR appears to be important in tumor progression.
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Repeated episodes of difficulty with arousal following general anesthesia in a patient with ulnar neuropathy.
J Anesth
PUBLISHED: 02-22-2009
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Delayed emergence following general anesthesia may be due to serious life-threatening disorders and deserves prompt evaluation. Rarely, delayed emergence has been attributed to a psychiatric or psychological cause. This report describes an otherwise healthy and mentally sound 52-year-old woman who experienced repeated dissociative episodes following general anesthesia for minor surgical procedures. These episodes lasted for 5 h and resulted in admission to the intensive care unit. The current literature is reviewed to identify commonalities among previously reported cases and to discuss different psychiatric and psychological mechanisms that can play a role in the development of this disorder.
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A presentation of longstanding toxoplasmosis chorioretinitis.
Optometry
PUBLISHED: 02-14-2009
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Toxoplasmosis gondii is the most common cause of focal necrotizing retinitis in healthy individuals. This case report describes a presentation of toxoplasmosis chorioretintis and reviews the current management options.
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Embryos in evolution: evo-devo at the Naples Zoological Station in 1874.
Theory Biosci.
PUBLISHED: 02-13-2009
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Eighteen seventy-four was a high point in evolutionary embryology. Thanks to Charles Darwin, the theory of evolution by natural selection provided a revolutionary new way of viewing the relationships and origins of organisms on Earth. Thanks to Ernst Haeckel, embryos were the way to study evolution (Haeckel in Generelle morphologie der organismen, vols 1, 2. Verlag Georg Reimer, Berlin, 1866)-it really was embryos in evolution-and recapitulation was in the air. Thanks to Anton Dohrn, a new research facility was on the ground, designed, located and structured to facilitate the study of embryos in evolution. Anton Dohrn devised, designed, financed, supervised the construction and then administered the Naples Zoological Station specifically so that researchers from all nations would have a facility where Darwins theory of evolution by natural selection could be tested. The zoologists who took advantage of the brand new facility within weeks of its opening late in 1873 established lines of research into evolutionary embryology, the field we now know as evolutionary developmental biology (evo-devo), the study of embryos in evolution. I examine the approach taken by Ambrosius Hubrecht, the first Dutch embryologist to undertake research at the station, and then evaluate the research of three British zoologists-E. Ray Lankester, Albert Dew-Smith, and Francis Maitland (Frank) Balfour. All four sought insights into origins, especially vertebrate origins that rested on comparative embryology, homology, germ layers, and a Darwinian approach to origins.
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Trajectories of resilience, resistance, and distress during ongoing terrorism: the case of Jews and Arabs in Israel.
J Consult Clin Psychol
PUBLISHED: 01-28-2009
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This is the 1st longitudinal examination of trajectories of resilience and resistance (rather than ill-being) among a national sample under ongoing threat of mass casualty. The authors interviewed a nationally representative sample of Jews and Arabs in Israel (N = 709) at 2 times during a period of terrorist and rocket attacks (2004-2005). The resistance trajectory, exhibiting few or no symptoms of traumatic stress and depression at both time points, was substantially less common (22.1%) than has previously been documented in studies following single mass casualty events. The resilience trajectory, exhibiting initial symptoms and becoming relatively nonsymptomatic, was evidenced by 13.5% of interviewees. The chronic distress trajectory was documented among a majority of participants (54.0%), and a small proportion of persons were initially relatively symptom-free but became distressed (termed delayed distress trajectory; 10.3%). Less psychosocial resource loss and majority status (Jewish) were the most consistent predictors of resistance and resilience trajectories, followed by greater socioeconomic status, greater support from friends, and less report of posttraumatic growth.
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THE DEFENSIVE NATURE OF BENEFIT FINDING DURING ONGOING TERRORISM: AN EXAMINATION OF A NATIONAL SAMPLE OF ISRAELI JEWS.
J Soc Clin Psychol
PUBLISHED: 01-01-2009
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A study examining the effects of terrorism on a national sample of 1,136 Jewish adults was conducted in Israel via telephone surveys, during the Second Intifada. The relationship between reports of positive changes occurring subsequent to terrorism exposure (i.e., Benefit finding), posttraumatic stress disorder (PTSD) symptom severity, and negative outgroup attitudes toward Palestinian citizens of Israel (PCI) was examined. Benefit finding was related to greater PTSD symptom severity. Further, Benefit finding was related to greater threat perception of PCI and ethnic exclusionism of PCI. Findings were consistent with hypotheses derived from theories of outgroup bias and support the anxiety buffering role of social affiliation posited by terror management theory. This study suggests that benefit finding may be a defensive coping strategy when expressed under the conditions of ongoing terrorism and external threat.
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A unified anatomy ontology of the vertebrate skeletal system.
PLoS ONE
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The skeleton is of fundamental importance in research in comparative vertebrate morphology, paleontology, biomechanics, developmental biology, and systematics. Motivated by research questions that require computational access to and comparative reasoning across the diverse skeletal phenotypes of vertebrates, we developed a module of anatomical concepts for the skeletal system, the Vertebrate Skeletal Anatomy Ontology (VSAO), to accommodate and unify the existing skeletal terminologies for the species-specific (mouse, the frog Xenopus, zebrafish) and multispecies (teleost, amphibian) vertebrate anatomy ontologies. Previous differences between these terminologies prevented even simple queries across databases pertaining to vertebrate morphology. This module of upper-level and specific skeletal terms currently includes 223 defined terms and 179 synonyms that integrate skeletal cells, tissues, biological processes, organs (skeletal elements such as bones and cartilages), and subdivisions of the skeletal system. The VSAO is designed to integrate with other ontologies, including the Common Anatomy Reference Ontology (CARO), Gene Ontology (GO), Uberon, and Cell Ontology (CL), and it is freely available to the community to be updated with additional terms required for research. Its structure accommodates anatomical variation among vertebrate species in development, structure, and composition. Annotation of diverse vertebrate phenotypes with this ontology will enable novel inquiries across the full spectrum of phenotypic diversity.
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Early lens ablation causes dramatic long-term effects on the shape of bones in the craniofacial skeleton of Astyanax mexicanus.
PLoS ONE
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The Mexican tetra, Astyanax mexicanus, exists as two morphs of a single species, a sighted surface morph and a blind cavefish. In addition to eye regression, cavefish have an increased number of taste buds, maxillary teeth and have an altered craniofacial skeleton compared to the sighted morph. We investigated the effect the lens has on the development of the surrounding skeleton, by ablating the lens at different time points during ontogeny. This unique long-term study sheds light on how early embryonic manipulations on the eye can affect the shape of the adult skull more than a year later, and the developmental window during which time these effects occur. The effects of lens ablation were analyzed by whole-mount bone staining, immunohistochemisty and landmark based morphometric analyzes. Our results indicate that lens ablation has the greatest impact on the skeleton when it is ablated at one day post fertilisation (dpf) compared to at four dpf. Morphometric analyzes indicate that there is a statistically significant difference in the shape of the supraorbital bone and suborbital bones four through six. These bones expand into the eye orbit exhibiting plasticity in their shape. Interestingly, the number of caudal teeth on the lower jaw is also affected by lens ablation. In contrast, the shape of the calvariae, the length of the mandible, and the number of mandibular taste buds are unaltered by lens removal. We demonstrate the plasticity of some craniofacial elements and the stability of others in the skull. Furthermore, this study highlights interactions present between sensory systems during early development and sheds light on the cavefish phenotype.
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An exploration of comorbid symptoms and clinical correlates of clinically significant hoarding symptoms.
Depress Anxiety
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Hoarding disorder (HD) is currently being considered for inclusion in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), yet remains poorly understood. Consensus is building that hoarding may constitute a separate disorder, although comorbidity remains high and complicates the diagnostic picture. The purpose of this investigation was to explore patterns of comorbidity among people who engage in hoarding behavior in order to better understand its clinical presentation and phenomenology.
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The comparative effectiveness of fine-needle aspiration cytology sampling policies: a simulation study.
Am. J. Clin. Pathol.
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Sample adequacy is an important aspect of overall fine-needle aspiration cytology (FNAC) performance. FNAC effectiveness is augmented by an increasing number of needle passes, but increased needle passes are associated with higher costs and greater risk of adverse events. The objective of this study was to compare the impact of several different sampling policies on FNAC effectiveness and adverse event rates using discrete event simulation. We compared 8 different sampling policies in 12 different sampling environments. All sampling policies were effective when the per-pass accuracy is high (>80%). Rapid on-site evaluation (ROSE) improves FNAC effectiveness when the per-pass adequacy rate is low. ROSE is unlikely to be cost-effective in sampling environments in which the per-pass adequacy is high. Alternative ROSE assessors (eg, cytotechnologists) may be a cost-effective alternative to pathologists when the per-pass adequacy rate is moderate (60%-80%) or when the number of needle passes is limited.
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Confirmatory factor analysis of the Beck Depression Inventory-II in bariatric surgery candidates.
Psychol Assess
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Screening for depression is an integral part of psychological evaluations conducted prior to bariatric surgery. The Beck Depression Inventory-II (BDI-II) is the most commonly used measure of depression in these treatment evaluations. The reliability and validity of the BDI-II has not yet been evaluated within bariatric surgery-seeking samples, evidencing a significant gap in the present literature. The purpose of the present study is to evaluate the structural validity of the BDI-II and to examine the reliability and convergent and criterion validity of this instrument within a bariatric surgery-seeking sample. The study population consisted of 505 ethnically diverse bariatric surgery candidates presenting for presurgical psychological evaluations in a midwestern urban academic medical center. Confirmatory factor analytic results indicated that a 3-factor model consisting of affective, cognitive, and somatic factors was the best fitting model of depression within this sample. Internal consistency reliability was satisfactory for each subscale, ranging from .72 to .82. Moderate to large correlations were observed between each BDI-II subscale and a measure of depression previously validated with bariatric surgery candidates indicating adequate convergent validity. On the basis of clinical interview, 14% of the sample was diagnosed with current major depression. Significant mean differences were observed between depressed and nondepressed patients with respect to each BDI-II subscale score, demonstrating criterion-related validity. The BDI-II is a reliable and valid measure of depression for bariatric surgery candidates. Understanding the factor structure of the BDI-II can be useful for planning potential presurgical psychological interventions.
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Cartilage on the move: cartilage lineage tracing during tadpole metamorphosis.
Dev. Growth Differ.
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The reorganization of cranial cartilages during tadpole metamorphosis is a set of complex processes. The fates of larval cartilage-forming cells (chondrocytes) and sources of adult chondrocytes are largely unknown. Individual larval cranial cartilages may either degenerate or remodel, while many adult cartilages appear to form de novo during metamorphosis. Determining the extent to which adult chondrocytes/cartilages are derived from larval chondrocytes during metamorphosis requires new techniques in chondrocyte lineage tracing. We have developed two transgenic systems to label cartilage cells throughout the body with fluorescent proteins. One system strongly labels early tadpole cartilages only. The other system inducibly labels forming cartilages at any developmental stage. We examined cartilages of the skull (viscero- and neurocranium), and identified larval cartilages that either resorb or remodel into adult cartilages. Our data show that the adult otic capsules, tecti anterius and posterius, hyale, and portions of Meckels cartilage are derived from larval chondrocytes. Our data also suggest that most adult cartilages form de novo, though we cannot rule out the potential for extreme larval chondrocyte proliferation or de- and re-differentiation, which could dilute our fluorescent protein signal. The transgenic lineage tracing strategies developed here are the first examples of inducible, skeleton-specific, lineage tracing in Xenopus.
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Cleft lip, nose, and palate: the nasal septum as the pacemaker for midfacial growth.
Oral Surg Oral Med Oral Pathol Oral Radiol
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The need to be aware of the dynamics of cartilage development and growth is encountered by surgeons whenever they attempt to correct craniofacial defects such as unilateral or bilateral cleft lip/cleft palate or midfacial injuries after trauma. Within the craniofacial region, the nasal septal cartilage and the sphenoethmoidal and sphenooccipital cranial synchondroses are distinguished from other craniofacial cartilages in possessing intrinsic growth potential. Indeed, growth of the nasal septal cartilage outstrips the growth of other skeletal and soft tissues in the midface to such an extent that it is the pacemaker for growth of the face and anterior portion of the skull. We revisit and reinforce the importance of the nasal septum as pacemaker with analysis of 3 classes of evidence: in vivo growth of the nasal septum in nonhuman mammalian models; composition and in vitro growth of nasal septal cartilage or chondrocytes; and experience from the surgical repair of unilateral or bilateral facial clefts.
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Parallelism, deep homology, and evo-devo.
Evol. Dev.
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Parallelism has been the subject of a number of recent studies that have resulted in reassessment of the term and the process. Parallelism has been aligned with homology leaving convergence as the only case of homoplasy, regarded as a transition between homologous and convergent characters, and defined as the independent evolution of genetic traits. Another study advocates abolishing the term parallelism and treating all cases of the independent evolution of characters as convergence. With the sophistication of modern genomics and genetic analysis, parallelism of characters of the phenotype is being discovered to reflect parallel genetic evolution. Approaching parallelism from developmental and genetic perspectives enables us to tease out the degree to which the reuse of pathways represent deep homology and is a major task for evolutionary developmental biology in the coming decades.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.