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Find video protocols related to scientific articles indexed in Pubmed.
Per3 length polymorphism in patients with type 2 diabetes mellitus.
Horm Mol Biol Clin Investig
PUBLISHED: 11-13-2014
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Abstract Background: A number of observations support the involvement of circadian clock genes in the regulation of metabolic processes. One of these circadian genes, Per3, exhibits a variable number tandem repeat length polymorphism, consisting of two alleles, namely four and five repeat alleles, in its exon 18. The objective of this study was to examine the existence of Per3 variants in patients with type 2 diabetes mellitus (T2DM) as compared to a non T2DM control group.
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Cognitive Distortions and Suicide Attempts.
Cognit Ther Res
PUBLISHED: 10-09-2014
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Although theorists have posited that suicidal individuals are more likely than non-suicidal individuals to experience cognitive distortions, little empirical work has examined whether those who recently attempted suicide are more likely to engage in cognitive distortions than those who have not recently attempted suicide. In the present study, 111 participants who attempted suicide in the 30 days prior to participation and 57 psychiatric control participants completed measures of cognitive distortions, depression, and hopelessness. Findings support the hypothesis that individuals who recently attempted suicide are more likely than psychiatric controls to experience cognitive distortions, even when controlling for depression and hopelessness. Fortune telling was the only cognitive distortion uniquely associated with suicide attempt status. However, fortune telling was no longer significantly associated with suicide attempt status when controlling for hopelessness. Findings underscore the importance of directly targeting cognitive distortions when treating individuals at risk for suicide.
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Apathy is associated with white matter abnormalities in anterior, medial brain regions in persons with HIV infection.
J Clin Exp Neuropsychol
PUBLISHED: 10-02-2014
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Apathy is a relatively common psychiatric syndrome in HIV infection, but little is known about its neural correlates. In the present study, we examined the associations between apathy and diffusion tensor imaging (DTI) indices in key frontal white matter regions in the thalamocorticostriatal circuit, which has been implicated in the expression of apathy. Nineteen participants with HIV infection and 19 demographically comparable seronegative comparison subjects completed the Apathy subscale of the Frontal Systems Behavioral Scale as a part of a comprehensive neuropsychiatric research evaluation. When compared to the seronegative participants, the HIV+ group had significantly more frontal white matter abnormalities. Within HIV+ persons, and as predicted, higher ratings of apathy were associated with greater white matter alterations in the anterior corona radiata, genu, and orbital medial prefrontal cortex. The associations between white matter alterations and apathy were independent of depression and were stronger among participants with lower current cluster of differentiation 4 (CD4) counts. All told, these findings indicate that apathy is independently associated with white matter abnormalities in anterior, medial brain regions in persons infected with HIV, particularly in the setting of lower current immune functioning, which may have implications for antiretroviral therapy.
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Should we listen to our clock to prevent type 2 diabetes mellitus?
Diabetes Res. Clin. Pract.
PUBLISHED: 08-12-2014
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The circadian clock drives a number of metabolic processes including energy intake, storage and utilization coupled with the sleep/wake cycles. Globally, the increasing prevalence of type 2 diabetes (T2DM) has become a significant international public health concern. In view of the heavy societal burden caused by diabetes, and further, to reduce its growing incidence, it is clearly essential to understand the causes of this disease and to devise more effective strategies for its treatment. Although many factors cause T2DM, this article centers on the role of circadian regulation of metabolism. The correlation between the increased occurrence of T2DM and the ubiquity of modern social pressures such as 24/7 lifestyles as well as nocturnal lighting conditions point strongly to the hypothesis that malfunctioning of circadian controls may be involved in the etiology of the illness. Nocturnal light exposure, unusual timing of food, irregular sleep/wake schedules and traveling between different time zones are some of the factors responsible for improper entrainment of the clock. Recent reports have proposed that strengthening of circadian clock functioning and proper timing of food intake could stabilize glucose homeostasis. This strategy thus represents a chronotherapeutic option for non-pharmaceutical intervention in treating T2DM patients.
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In vivo functional analysis of a nuclear restorer PPR protein.
BMC Plant Biol.
PUBLISHED: 06-30-2014
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BackgroundNuclear restorers of cytoplasmic male fertility (CMS) act to suppress the male sterile phenotype by down-regulating the expression of novel CMS-specifying mitochondrial genes. One such restorer gene is Rfo, which restores fertility to the radish Ogura or ogu CMS. Rfo, like most characterized restorers, encodes a pentatricopeptide repeat (PPR) protein, a family of eukaryotic proteins characterized by tandem repeats of a 35 amino acid motif. While over 400 PPR genes are found in characterized plant genomes and the importance of this gene family in organelle gene expression is widely recognized, few detailed in vivo assessments of primary structure-function relationships in this protein family have been conducted.ResultsIn contrast to earlier studies, which identified 16 or 17 PPR domains in the Rfo protein, we now find, using a more recently developed predictive tool, that Rfo has 18 repeat domains with the additional domain N-terminal to the others. Comparison of transcript sequences from pooled rfo/rfo plants with pooled Rfo/Rfo plants of a mapping population led to the identification of a non-restoring rfo allele with a 12 bp deletion in the fourth domain. Introduction into ogu CMS plants of a genetic construct in which this deletion had been introduced into Rfo led to a partial loss in the capacity to produce viable pollen, as assessed by vital staining, pollen germination and the capacity for seed production following pollination of CMS plants. The degree of viable pollen production among different transgenic plants roughly correlated with the copy number of the introduced gene and with the reduction of the levels of the ORF138 CMS-associated protein. All other constructs tested, including one in which only the C-terminal PPR repeat was deleted and another in which this repeat was replaced by the corresponding domain of the related, non-restoring gene, PPR-A, failed to result in any measure of fertility restoration.ConclusionsThe identification of the additional PPR domain in Rfo indicates that the protein, apart from its N-terminal mitochondrial targeting presequence, consists almost entirely of PPR repeats. The newly identified rfo allele carries the same 4 amino acid deletion as that found in the neighboring, related, non-restoring PPR gene, PPR-A. Introduction of this four amino acid deletion into a central domain the Rfo protein, however, only partially reduces its restoration capacity, even though this alteration might be expected to alter the spacing between the adjoining repeats. All other tested alterations, generated by deleting specific PPR repeats or exchanging repeats with corresponding domains of PPR-A, led to a complete loss of restorer function. Overall we demonstrate that introduction of targeted alterations of Rfo into ogu CMS plants provides a sensitive in vivo readout for analysis of the relationship between primary structure and biological function in this important family of plant proteins.
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Invader immunology: invasion history alters immune system function in cane toads (Rhinella marina) in tropical Australia.
Ecol. Lett.
PUBLISHED: 06-24-2014
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Because an individual's investment into the immune system may modify its dispersal rate, immune function may evolve rapidly in an invader. We collected cane toads (Rhinella marina) from sites spanning their 75-year invasion history in Australia, bred them, and raised their progeny in standard conditions. Evolved shifts in immune function should manifest as differences in immune responses among the progeny of parents collected in different locations. Parental location did not affect the offspring's cell-mediated immune response or stress response, but blood from the offspring of invasion-front toads had more neutrophils, and was more effective at phagocytosis and killing bacteria. These latter measures of immune function are negatively correlated with rate of dispersal in free-ranging toads. Our results suggest that the invasion of tropical Australia by cane toads has resulted in rapid genetically based compensatory shifts in the aspects of immune responses that are most compromised by the rigours of long-distance dispersal.
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A review of evidence-based follow-up care for suicide prevention: where do we go from here?
Am J Prev Med
PUBLISHED: 06-04-2014
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Follow-up services are an important component of a comprehensive, national strategy for suicide prevention. Increasing our knowledge of effective follow-up care has been identified as an Aspirational Goal by The National Action Alliance for Suicide Prevention's Research Prioritization Task Force.
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Evidence-based psychotherapies for suicide prevention: future directions.
Am J Prev Med
PUBLISHED: 05-28-2014
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Psychotherapeutic interventions targeting suicidal thoughts and behaviors are essential for reducing suicide attempts and deaths by suicide. To determine whether specific psychotherapies are efficacious in preventing suicide and suicide-related behaviors, it is necessary to rigorously evaluate therapies using RCTs. To date, a number of RCTs have demonstrated efficacy for several interventions focused on preventing suicide attempts and reducing suicidal ideation. Although these studies have contributed greatly to the understanding of treatment for suicidal thoughts and behaviors, the extant literature is hampered by a number of gaps and methodologic limitations. Thus, further research employing increased methodologic rigor is needed to improve psychotherapeutic suicide prevention efforts. The aims of this paper are to briefly review the state of the science for psychotherapeutic interventions for suicide prevention, discuss gaps and methodologic limitations of the extant literature, and suggest next steps for improving future studies.
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Safety Planning for Military (SAFE MIL): rationale, design, and safety considerations of a randomized controlled trial to reduce suicide risk among psychiatric inpatients.
Contemp Clin Trials
PUBLISHED: 03-21-2014
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Mental health related hospitalizations and suicide are both significant public health problems within the United States Department of Defense (DoD). To date, few evidence-based suicide prevention programs have been developed for delivery to military personnel and family members admitted for psychiatric inpatient care due to suicidal self-directed violence. This paper describes the rationale and detailed methodology for a study called Safety Planning for Military (SAFE MIL) which involves a randomized controlled trial (RCT) at the largest military treatment facility in the United States. The purpose of this study is to test the efficacy of a brief, readily accessible, and personalized treatment called the Safety Planning Intervention (Stanley and Brown, 2012). Primary outcomes, measured by blinded assessors at one and six months following psychiatric discharge, include suicide ideation, suicide-related coping, and attitudes toward help seeking. Additionally, given the study's focus on a highly vulnerable patient population, a description of safety considerations for human subjects' participation is provided. Based on this research team's experience, the implementation of an infrastructure in support of RCT research within DoD settings and the processing of regulatory approvals for a clinical trial with high risk suicidal patients are expected to take up to 18-24 months. Recommendations for expediting the advancement of clinical trials research within the DoD are provided in order to maximize cost efficacy and minimize the research to practice gap.
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Not all distraction is bad: working memory vulnerability to implicit socioemotional distraction correlates with negative symptoms and functional impairment in psychosis.
Schizophr Res Treatment
PUBLISHED: 02-27-2014
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This study investigated implicit socioemotional modulation of working memory (WM) in the context of symptom severity and functional status in individuals with psychosis (N = 21). A delayed match-to-sample task was modified wherein task-irrelevant facial distracters were presented early and briefly during the rehearsal of pseudoword memoranda that varied incrementally in load size (1, 2, or 3 syllables). Facial distracters displayed happy, sad, or emotionally neutral expressions. Implicit socioemotional modulation of WM was indexed by subtracting task accuracy on nonfacial geometrical distraction trials from facial distraction trials. Results indicated that the amount of implicit socioemotional modulation of high WM load accuracy was significantly associated with negative symptoms (r = 0.63, P < 0.01), role functioning (r = -0.50, P < 0.05), social functioning (r = -0.55, P < 0.01), and global assessment of functioning (r = -0.53, P < 0.05). Specifically, greater attentional distraction of high WM load was associated with less severe symptoms and functional impairment. This study demonstrates the importance of the WM-socioemotional interface in influencing clinical and psychosocial functional status in psychosis.
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Cutaneous metastasis of prostate cancer: a case report and review of the literature with bioinformatics analysis of multiple healthcare delivery networks.
J. Cutan. Pathol.
PUBLISHED: 02-26-2014
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Distant cutaneous metastases of prostate carcinomas are extremely rare, despite its high incidence and prevalence. Most cases are either a result of local extension, such as into seminal vesicles or distant metastases to bone. Few cases of true cutaneous metastatic prostate carcinoma exist in the literature. Clinically, cutaneous prostate carcinoma has been reported to mimic many other conditions, such as cellulitis, sebaceous cysts, zosteriform lesions, telangectasias and more, resulting in poor recognition. We report a case of distant cutaneous metastasis of prostate carcinoma and recent review of the literature with an analysis of de-identified patient records from multiple healthcare delivery networks. A diagnosis of metastatic prostate carcinoma may have been easily overlooked given the location and nature of the rash. Reviewing case reports and using aggregated electronic health records (EHRs), we find that fewer than 0.1% of all prostate carcinomas result in cutaneous metastases, compared with much higher rates in other types of cancers. Coupled with the low frequency of metastases to skin, careful consideration must be taken when evaluating a rash in a patient with a prior history of cancer. A complete clinical history and strong suspicion would be required to make a diagnosis of cutaneous metastases of the prostate.
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Validity of HydraTrend reagent strips for the assessment of hydration status.
J Strength Cond Res
PUBLISHED: 02-21-2014
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Hydration is used by athletic governing organizations for weight class eligibility. The measurement of urine specific gravity (USG) as a measure of hydration by reagent strips is a controversial issue. The purpose of this study was to determine the validity of HydraTrend reagent strips that facilitate the correction of USG for alkaline urine samples against refractometry for the assessment of USG. Fifty-one participants (33 males, age = 22.3 ± 1.3 years; 18 females, age = 22.4 ± 1.2 years) provided 84 urine samples. The samples were tested for USG using refractometry and reagent strips and for pH using reagent strips and a digital pH meter. Strong correlation coefficients were found between refractometry and reagent strips for USG (rs(82) = 0.812, p < 0.01) and between reagent strips and pH meter for pH (rs(82) = 0.939, p < 0.01). It was observed that false negative results for National Collegiate Athletic Association (NCAA) requirements (fail refractometry with USG >1.020, pass reagent strips with USG ?1.020) occurred 39% (33/84) of the time and false negative results for National Federation of State High School Association (NFHS) requirements (fail refractometry with USG >1.025, pass reagent strips with USG ?1.025) occurred 14% (12/84) of the time. There were no false positives (pass refractometry and fail reagent strips) for NCAA or NFHS requirements. These data show that refractometry and reagent strips have strong positive correlations. However, the risk of a false negative result leading to incorrect certification of euhydration status outweighs the benefits of the HydraTrend reagent strips for the measurement of USG.
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Adaptive radiation, correlated and contingent evolution, and net species diversification in Bromeliaceae.
Mol. Phylogenet. Evol.
PUBLISHED: 02-12-2014
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We present an integrative model predicting associations among epiphytism, the tank habit, entangling seeds, C? vs. CAM photosynthesis, avian pollinators, life in fertile, moist montane habitats, and net rates of species diversification in the monocot family Bromeliaceae. We test these predictions by relating evolutionary shifts in form, physiology, and ecology to time and ancestral distributions, quantifying patterns of correlated and contingent evolution among pairs of traits and analyzing the apparent impact of individual traits on rates of net species diversification and geographic expansion beyond the ancestral Guayana Shield. All predicted patterns of correlated evolution were significant, and the temporal and spatial associations of phenotypic shifts with orogenies generally accorded with predictions. Net rates of species diversification were most closely coupled to life in fertile, moist, geographically extensive cordilleras, with additional significant ties to epiphytism, avian pollination, and the tank habit. The highest rates of net diversification were seen in the bromelioid tank-epiphytic clade (D(crown) = 1.05 My?¹), associated primarily with the Serra do Mar and nearby ranges of coastal Brazil, and in the core tillandsioids (D(crown) = 0.67 My?¹), associated primarily with the Andes and Central America. Six large-scale adaptive radiations and accompanying pulses of speciation account for 86% of total species richness in the family. This study is among the first to test a priori hypotheses about the relationships among phylogeny, phenotypic evolution, geographic spread, and net species diversification, and to argue for causality to flow from functional diversity to spatial expansion to species diversity.
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Disentangling working memory processes during spatial span assessment: a modeling analysis of preferred eye movement strategies.
J Clin Exp Neuropsychol
PUBLISHED: 02-05-2014
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The neurocognitive processes involved during classic spatial working memory (SWM) assessment were investigated by examining naturally preferred eye movement strategies. Cognitively healthy adult volunteers were tested in a computerized version of the Corsi Block-Tapping Task--a spatial span task requiring the short term maintenance of a series of locations presented in a specific order--coupled with eye tracking. Modeling analysis was developed to characterize eye-tracking patterns across all task phases, including encoding, retention, and recall. Results revealed a natural preference for local gaze maintenance during both encoding and retention, with fewer than 40% fixated targets. These findings contrasted with the stimulus retracing pattern expected during recall as a result of task demands, with 80% fixated targets. Along with participants' self-reported strategies of mentally "making shapes," these results suggest the involvement of covert attention shifts and higher order cognitive Gestalt processes during spatial span tasks, challenging instrument validity as a single measure of SWM storage capacity.
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Early and progressive circadian abnormalities in Huntington's disease sheep are unmasked by social environment.
Hum. Mol. Genet.
PUBLISHED: 01-31-2014
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Insidious changes in behaviour herald the onset of progressive neurodegenerative disorders such as Huntington's disease (HD), sometimes years before overt symptoms are seen. Sleep and circadian disturbances are particularly disruptive symptoms in patients with neurological disorders, but they are difficult to measure in humans. Here we studied circadian behaviour in transgenic HD sheep expressing the full-length human huntingtin protein with an expanded CAG repeat mutation in the juvenile range. Young HD sheep with no other symptoms exhibited circadian behavioural abnormalities that worsened with age. The most obvious change was a disturbed evening behaviour reminiscent of 'sundowning' that is seen in some patients with dementia. There were no structural abnormalities seen with magnetic resonance imaging, even in 5-year-old HD sheep. Interestingly, detection of the circadian abnormalities depended upon their social grouping. Abnormalities emerged in sheep kept in an 'HD-only' flock, whereas the behaviour of HD sheep kept mixed with normal sheep was relatively normal. Sleep-wake abnormalities in HD patients are also likely to be hidden, and may precede overt symptoms by many years. Sleep disruption has deleterious effects, even in normal people. The knock-on effects of sleep-wake disturbance may exacerbate, or even cause symptoms such as irritability and depression that are common in early stage HD patients. HD sheep will be useful models for probing the mechanisms underlying circadian behavioural disorder in HD.
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Transcranial direct current stimulation modulates activation and effective connectivity during spatial navigation.
Brain Stimul
PUBLISHED: 01-30-2014
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Allocentric navigation declines with age and neurologic disease whereas egocentric navigation does not; differences that likely arise from maladaptive changes in brain regions mediating spatial (parietal cortex; hippocampus) but not procedural processing (caudate nucleus). Transcranial direct current stimulation (tDCS) holds promise for treating such decline given its ability to modulate neuronal excitability, but its effects have yet to be examined on spatial navigation.
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nMAT4, a maturase factor required for nad1 pre-mRNA processing and maturation, is essential for holocomplex I biogenesis in Arabidopsis mitochondria.
Plant J.
PUBLISHED: 01-17-2014
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Group II introns are large catalytic RNAs that are found in bacteria and organellar genomes of lower eukaryotes, but are particularly prevalent within mitochondria in plants, where they are present in many critical genes. The excision of plant mitochondrial introns is essential for respiratory functions, and is facilitated in vivo by various protein cofactors. Typical group II introns are classified as mobile genetic elements, consisting of the self-splicing ribozyme and its own intron-encoded maturase protein. A hallmark of maturases is that they are intron-specific, acting as cofactors that bind their intron-containing pre-RNAs to facilitate splicing. However, the degeneracy of the mitochondrial introns in plants and the absence of cognate intron-encoded maturase open reading frames suggest that their splicing in vivo is assisted by 'trans'-acting protein factors. Interestingly, angiosperms harbor several nuclear-encoded maturase-related (nMat) genes that contain N-terminal mitochondrial localization signals. Recently, we established the roles of two of these paralogs in Arabidopsis, nMAT1 and nMAT2, in the splicing of mitochondrial introns. Here we show that nMAT4 (At1g74350) is required for RNA processing and maturation of nad1 introns 1, 3 and 4 in Arabidopsis mitochondria. Seed germination, seedling establishment and development are strongly affected in homozygous nmat4 mutants, which also show modified respiration phenotypes that are tightly associated with complex I defects.
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A multi-scanner study of subcortical brain volume abnormalities in schizophrenia.
Psychiatry Res
PUBLISHED: 01-13-2014
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Schizophrenia patients show significant subcortical brain abnormalities. We examined these abnormalities using automated image analysis software and provide effect size estimates for prospective multi-scanner schizophrenia studies. Subcortical and intracranial volumes were obtained using FreeSurfer 5.0.0 from high-resolution structural imaging scans from 186 schizophrenia patients (mean age±S.D.=38.9±11.6, 78% males) and 176 demographically similar controls (mean age±S.D.=37.5±11.2, 72% males). Scans were acquired from seven 3-Tesla scanners. Univariate mixed model regression analyses compared between-group volume differences. Weighted mean effect sizes (and number of subjects needed for 80% power at ?=0.05) were computed based on the individual single site studies as well as on the overall multi-site study. Schizophrenia patients have significantly smaller intracranial, amygdala, and hippocampus volumes and larger lateral ventricle, putamen and pallidum volumes compared with healthy volunteers. Weighted mean effect sizes based on single site studies were generally larger than effect sizes computed based on analysis of the overall multi-site sample. Prospectively collected structural imaging data can be combined across sites to increase statistical power for meaningful group comparisons. Even when using similar scan protocols at each scanner, some between-site variance remains. The multi-scanner effect sizes provided by this study should help in the design of future multi-scanner schizophrenia imaging studies.
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Effects of melatonin and epiphyseal proteins on fluoride-induced adverse changes in antioxidant status of heart, liver, and kidney of rats.
Adv Pharmacol Sci
PUBLISHED: 01-11-2014
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Several experimental and clinical reports indicated the oxidative stress-mediated adverse changes in vital organs of human and animal in fluoride (F) toxicity. Therefore, the present study was undertaken to evaluate the therapeutic effect of buffalo (Bubalus bubalis) epiphyseal (pineal) proteins (BEP) and melatonin (MEL) against F-induced oxidative stress in heart, liver, and kidney of experimental adult female rats. To accomplish this experimental objective, twenty-four adult female Wistar rats (123-143 g body weights) were divided into four groups, namely, control, F, F + BEP, and F + MEL and were administered sodium fluoride (NaF, 150?ppm elemental F in drinking water), MEL (10?mg/kg BW, i.p.), and BEP (100?µg/kg BW, i.p.) for 28 days. There were significantly (P < 0.05) high levels of lipid peroxidation and catalase and low levels of reduced glutathione, superoxide dismutase, glutathione reductase, and glutathione peroxidase in cardiac, hepatic, and renal tissues of F-treated rats. Administration of BEP and MEL in F-treated rats, however, significantly (P < 0.05) attenuated these adverse changes in all the target components of antioxidant defense system of cardiac, hepatic, and renal tissues. The present data suggest that F can induce oxidative stress in liver, heart, and kidney of female rats which may be a mechanism in F toxicity and these adverse effects can be ameliorated by buffalo (Bubalus bubalis) epiphyseal proteins and melatonin by upregulation of antioxidant defense system of heart, liver, and kidney of rats.
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Invasive cane toads: social facilitation depends upon an individual's personality.
PLoS ONE
PUBLISHED: 01-01-2014
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Individual variation in behavioural traits (including responses to social cues) may influence the success of invasive populations. We studied the relationship between sociality and personality in invasive cane toads (Rhinella marina) from a recently established population in tropical Australia. In our field experiments, we manipulated social cues (the presence of a feeding conspecific) near a food source. We captured and compared toads that only approached feeding sites where another toad was already present, with conspecifics that approached unoccupied feeding sites. Subsequent laboratory trials showed correlated personality differences (behavioural syndromes) between these two groups of toads. For example, toads that approached already-occupied rather than unoccupied feeding sites in the field, took longer to emerge from a shelter-site in standardized trials, suggesting these individuals are 'shy' (whereas toads that approached unoccupied feeding stations tended to be 'bold'). Manipulating hunger levels did not abolish this difference. In feeding trials, a bold toad typically outcompeted a shy toad under conditions of low prey availability, but the outcome was reversed when multiple prey items were present. Thus, both personality types may be favored under different circumstances. This invasive population of toads contains individuals that exhibit a range of personalities, hinting at the existence of a wide range of social dynamics in taxa traditionally considered to be asocial.
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Immune response varies with rate of dispersal in invasive cane toads (Rhinella marina).
PLoS ONE
PUBLISHED: 01-01-2014
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What level of immunocompetence should an animal maintain while undertaking long-distance dispersal? Immune function (surveillance and response) might be down-regulated during prolonged physical exertion due to energy depletion, and/or to avoid autoimmune reactions arising from damaged tissue. On the other hand, heightened immune vigilance might be favored if the organism encounters novel pathogens as it enters novel environments. We assessed the links between immune defense and long-distance movement in a population of invasive cane toads (Rhinella marina) in Australia. Toads were radio-tracked for seven days to measure their activity levels and were then captured and subjected to a suite of immune assays. Toads that moved further showed decreased bacteria-killing ability in their plasma and decreased phagocytic activity in their whole blood, but a heightened skin-swelling response to phytohemagglutinin. Baseline and post-stress corticosterone levels were unrelated to distance moved. Thus, long-distance movement in cane toads is associated with a dampened response in some systems and enhanced response in another. This pattern suggests that sustained activity is accompanied by trade-offs among immune components rather than an overall down or up-regulation. The finding that high mobility is accompanied by modification of the immune system has important implications for animal invasions.
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Group II intron splicing factors in plant mitochondria.
Front Plant Sci
PUBLISHED: 01-01-2014
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Group II introns are large catalytic RNAs (ribozymes) which are found in bacteria and organellar genomes of several lower eukaryotes, but are particularly prevalent within the mitochondrial genomes (mtDNA) in plants, where they reside in numerous critical genes. Their excision is therefore essential for mitochondria biogenesis and respiratory functions, and is facilitated in vivo by various protein cofactors. Typical group II introns are classified as mobile genetic elements, consisting of the self-splicing ribozyme and its intron-encoded maturase protein. A hallmark of maturases is that they are intron specific, acting as cofactors which bind their own cognate containing pre-mRNAs to facilitate splicing. However, the plant organellar introns have diverged considerably from their bacterial ancestors, such as they lack many regions which are necessary for splicing and also lost their evolutionary related maturase ORFs. In fact, only a single maturase has been retained in the mtDNA of various angiosperms: the matR gene encoded in the fourth intron of the NADH-dehydrogenase subunit 1 (nad1 intron 4). Their degeneracy and the absence of cognate ORFs suggest that the splicing of plant mitochondria introns is assisted by trans-acting cofactors. Interestingly, in addition to MatR, the nuclear genomes of angiosperms also harbor four genes (nMat 1-4), which are closely related to maturases and contain N-terminal mitochondrial localization signals. Recently, we established the roles of two of these paralogs in Arabidopsis, nMAT1 and nMAT2, in the splicing of mitochondrial introns. In addition to the nMATs, genetic screens led to the identification of other genes encoding various factors, which are required for the splicing and processing of mitochondrial introns in plants. In this review we will summarize recent data on the splicing and processing of mitochondrial introns and their implication in plant development and physiology, with a focus on maturases and their accessory splicing cofactors.
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Comparison of the Effectiveness of Cognitive Behavioral Therapy for Depression among Older Versus Younger Veterans: Results of a National Evaluation.
J Gerontol B Psychol Sci Soc Sci
PUBLISHED: 11-13-2013
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Objectives.The effectiveness of cognitive behavioral therapy for depression (CBT-D) among older adults in routine clinical settings has received limited attention. The current article examines and compares outcomes of older versus younger veterans receiving CBT-D nationally.Method.Patient outcomes were assessed using the Beck Depression Inventory-II and World Health Organization Quality of Life-BREF. Therapeutic alliance was assessed using the Working Alliance Inventory-Short Revised.
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Addressing risks to advance mental health research.
JAMA Psychiatry
PUBLISHED: 11-01-2013
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IMPORTANCE Risk communication and management are essential to the ethical conduct of research, yet addressing risks may be time consuming for investigators and institutional review boards may reject study designs that seem too risky. This can discourage needed research, particularly in higher-risk protocols or those enrolling potentially vulnerable individuals, such as those with some level of suicidality. Improved mechanisms for addressing research risks may facilitate much needed psychiatric research. OBJECTIVE To provide mental health researchers with practical approaches to (1) identify and define various intrinsic research risks, (2) communicate these risks to others (eg, potential participants, regulatory bodies, and society), (3) manage these risks during the course of a study, and (4) justify the risks. EVIDENCE REVIEW As part of a National Institute of Mental Health-funded scientific meeting series, a public conference and a closed-session expert panel meeting were held on managing and disclosing risks in mental health clinical trials. The expert panel reviewed the literature with a focus on empirical studies and developed recommendations for best practices and further research on managing and disclosing risks in mental health clinical trials. No institutional review board-review was required because there were no human subjects. FINDINGS Challenges, current data, practical strategies, and topics for future research are addressed for each of 4 key areas pertaining to management and disclosure of risks in clinical trials: identifying and defining risks, communicating risks, managing risks during studies, and justifying research risks. CONCLUSIONS AND RELEVANCE Empirical data on risk communication, managing risks, and the benefits of research can support the ethical conduct of mental health research and may help investigators better conceptualize and confront risks and to gain institutional review board-approval.
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Measuring the Prevalence of Current, Severe Symptoms of Mental Health Problems in a Canadian Correctional Population: Implications for Delivery of Mental Health Services for Inmates.
Int J Offender Ther Comp Criminol
PUBLISHED: 10-23-2013
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This study measured the prevalence of current, severe symptoms of a mental health problem in an adult population of inmates in Ontario, Canada. The Resident Assessment Instrument-Mental Health was used to measure the prevalence of symptoms among a sample of 522 inmates. Propensity score weighting was used to adjust for nonrandom selection into the sample. Prevalence estimates were derived for the total inmate population, remand and sentenced, males and females, and Aboriginal and non-Aboriginal inmates. It is estimated that 41.1% of Ontario inmates will have at least one current, severe symptom of a mental health problem; of this group, 13.0%, will evidence two or more symptoms. The number of symptoms is strongly associated with presence of a psychiatric diagnosis and level of mental health care needs. Female (35.1%) and Aboriginal (18.7%) inmates are more likely to demonstrate two or more current, severe symptoms. Greater efforts must be made to bridge the gap between correctional and mental health care systems to ensure inmates in correctional facilities can access and receive appropriate mental health care services.
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Using neuroimaging to inform clinical practice for the diagnosis and treatment of mild cognitive impairment.
Clin. Geriatr. Med.
PUBLISHED: 10-08-2013
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Advances in structural and functional neuroimaging techniques have unquestionably improved understanding of the development and progression of Alzheimer disease (AD), with evidence supporting regional (and network) change that underlies cognitive decline across the "healthy" aging/mild cognitive impairment (MCI)/AD spectrum. This review focuses on visual rating scales and volumetric analyses that could be easily integrated into clinical practice, followed by a review of functional neuroimaging findings suggesting that widespread cerebral dysfunction underlies the learning and memory deficits in MCI. Evidence of preserved neuroplasticity in this population and that cognitive rehabilitation techniques may capitalize on this plasticity to improve cognition in those with MCI is also discussed.
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Rapid shifts in dispersal behavior on an expanding range edge.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-29-2013
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Dispersal biology at an invasion front differs from that of populations within the range core, because novel evolutionary and ecological processes come into play in the nonequilibrium conditions at expanding range edges. In a world where species range limits are changing rapidly, we need to understand how individuals disperse at an invasion front. We analyzed an extensive dataset from radio-tracking invasive cane toads (Rhinella marina) over the first 8 y since they arrived at a site in tropical Australia. Movement patterns of toads in the invasion vanguard differed from those of individuals in the same area postcolonization. Our model discriminated encamped versus dispersive phases within each toads movements and demonstrated that pioneer toads spent longer periods in dispersive mode and displayed longer, more directed movements while they were in dispersive mode. These analyses predict that overall displacement per year is more than twice as far for toads at the invasion front compared with those tracked a few years later at the same site. Studies on established populations (or even those a few years postestablishment) thus may massively underestimate dispersal rates at the leading edge of an expanding population. This, in turn, will cause us to underpredict the rates at which invasive organisms move into new territory and at which native taxa can expand into newly available habitat under climate change.
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Cost-effectiveness of low-molecular-weight heparin compared with aspirin for prophylaxis against venous thromboembolism after total joint arthroplasty.
J Bone Joint Surg Am
PUBLISHED: 07-19-2013
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There is controversy regarding the most appropriate strategy to prevent venous thromboembolism following total joint arthroplasty. Our objective was to estimate the lifetime costs, quality-adjusted life-years (QALYs), and costs per QALY gained using low-molecular-weight heparin compared with low-dose aspirin for two weeks after total knee or total hip arthroplasty in patients with no history of venous thromboembolism.
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Experimental manipulation of working memory model parameters: an exercise in construct validity.
Psychol Assess
PUBLISHED: 07-01-2013
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As parametric cognitive models become more commonly used to measure individual differences, the construct validity of the interpretation of individual model parameters needs to be well established. The validity of the interpretation of 2 parameters of a formal model of the Continuous Recognition Memory Test (CRMT) was investigated in 2 experiments. The 1st study found that manipulating the percentage of trials on the CRMT for which degraded pseudowords were presented altered the models stimulus encoding parameter but not the working memory displacement parameter. The 2nd experiment showed that manipulating the number of syllables forming a pseudoword altered the models working memory displacement parameter for each syllable added to the pseudoword. Findings from both experiments supported the construct representation of the model parameters, supporting the construct validity of the models use to interpret CRMT performance. Combining parametric models with the manipulation of factors that theory predicts are related to model parameters provides an approach to construct validation that bridges experimental and individual difference methods of studying human cognition.
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"Frontal systems" behaviors in comorbid human immunodeficiency virus infection and methamphetamine dependency.
Psychiatry Res
PUBLISHED: 03-27-2013
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Human immunodeficiency virus (HIV) infection and methamphetamine (MA) dependence are associated with neural injury preferentially involving frontostriatal circuits. Little is known, however, about how these commonly comorbid conditions impact behavioral presentations typically associated with frontal systems dysfunction. Our sample comprised 47 HIV-uninfected/MA-nondependent; 25 HIV-uninfected/MA-dependent; 36 HIV-infected/MA-nondependent; and 28 HIV-infected/MA-dependent subjects. Participants completed self-report measures of "frontal systems" behaviors, including impulsivity/disinhibition, sensation-seeking, and apathy. They also underwent comprehensive neurocognitive and neuropsychiatric assessments that allowed for detailed characterization of neurocognitive deficits and comorbid/premorbid conditions, including lifetime Mood and Substance Use Disorders, Attention-Deficit/Hyperactivity Disorder, and Antisocial Personality Disorder. Multivariable regression models adjusting for potential confounds (i.e., demographics and comorbid/premorbid conditions) showed that MA dependence was independently associated with increased impulsivity/disinhibition, sensation-seeking and apathy, and HIV infection with greater apathy. However, we did not see synergistic/additive effects of HIV and MA on frontal systems behaviors. Global neurocognitive impairment was relatively independent of the frontal systems behaviors, which is consistent with the view that these constructs may have relatively separable biopsychosocial underpinnings. Future research should explore whether both neurocognitive impairment and frontal systems behaviors may independently contribute to everyday functioning outcomes relevant to HIV and MA.
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Linking mathematical modeling with human neuroimaging to segregate verbal working memory maintenance processes from stimulus encoding.
Neuropsychology
PUBLISHED: 03-27-2013
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A fundamental dissociation for most working memory (WM) theories involves the separation of sensory-perceptual encoding of stimulus information from the maintenance of this information. The present paper reports tests of this separability hypothesis for visually presented pseudowords at both mathematical and neuroimaging levels of analysis.
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Joint modeling compliance and outcome for causal analysis in longitudinal studies.
Stat Med
PUBLISHED: 03-06-2013
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This article discusses joint modeling of compliance and outcome for longitudinal studies when noncompliance is present. We focus on two-arm randomized longitudinal studies in which subjects are randomized at baseline, treatment is applied repeatedly over time, and compliance behaviors and clinical outcomes are measured and recorded repeatedly over time. In the proposed Markov compliance and outcome model, we use the potential outcome framework to define pre-randomization principal strata from the joint distribution of compliance under treatment and control arms, and estimate the effect of treatment within each principal strata. Besides the causal effect of the treatment, our proposed model can estimate the impact of the causal effect of the treatment at a given time on future compliance. Bayesian methods are used to estimate the parameters. The results are illustrated using a study assessing the effect of cognitive behavior therapy on depression. A simulation study is used to assess the repeated sampling properties of the proposed model. Copyright © 2013 John Wiley & Sons, Ltd.
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Discovery of 1-(1,3,5-triazin-2-yl)piperidine-4-carboxamides as inhibitors of soluble epoxide hydrolase.
Bioorg. Med. Chem. Lett.
PUBLISHED: 02-13-2013
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1-(1,3,5-Triazin-yl)piperidine-4-carboxamide inhibitors of soluble epoxide hydrolase were identified from high through-put screening using encoded library technology. The triazine heterocycle proved to be a critical functional group, essential for high potency and P450 selectivity. Phenyl group substitution was important for reducing clearance, and establishing good oral exposure. Based on this lead optimization work, 1-[4-methyl-6-(methylamino)-1,3,5-triazin-2-yl]-N-{[[4-bromo-2-(trifluoromethoxy)]-phenyl]methyl}-4-piperidinecarboxamide (27) was identified as a useful tool compound for in vivo investigation. Robust effects on a serum biomarker, 9, 10-epoxyoctadec-12(Z)-enoic acid (the epoxide derived from linoleic acid) were observed, which provided evidence of robust in vivo target engagement and the suitability of 27 as a tool compound for study in various disease models.
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Parallel psychometric and cognitive modeling analyses of the Penn Face Memory Test in the Army Study to Assess Risk and Resilience in Servicemembers.
J Clin Exp Neuropsychol
PUBLISHED: 02-05-2013
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The psychometric properties of the Penn Face Memory Test (PFMT) were investigated in a large sample (4,236 participants) of U.S. Army Soldiers undergoing computerized neurocognitive testing. Data were drawn from the initial phase of the Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS), a large-scale study directed towards identifying risk and resilience factors for suicidal behavior and other stress-related disorders in Army Soldiers. In this paper, we report parallel psychometric and cognitive modeling analyses of the PFMT to determine whether ability estimates derived from the measure are precise and valid indicators of memory in the Army STARRS sample.
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The early toad gets the worm: cane toads at an invasion front benefit from higher prey availability.
J Anim Ecol
PUBLISHED: 01-29-2013
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In biological invasions, rates of range expansion tend to accelerate through time. What kind of benefits to more rapidly dispersing organisms might impose natural selection for faster rates of dispersal, and hence the evolution of range-edge acceleration? We can answer that question by comparing fitness-relevant ecological traits of individuals at the invasion front compared with conspecifics in the same area a few years post-invasion. In tropical Australia, the rate of invasion by cane toads (Rhinella marina) has increased substantially over recent decades, due to shifts in heritable traits. Our data on field-collected cane toads at a recently invaded site in the Australian wet-dry tropics span a 5-year period beginning with toad arrival. Compared with conspecifics that we monitored in the same sites post-invasion, toads in the invasion vanguard exhibited higher feeding rates, larger energy stores, better body condition and faster growth. Three processes may have contributed to this pattern: (i) higher prey availability at the front (perhaps due to reduced competition from conspecifics); (ii) the lack of viability-reducing parasites and pathogens in invasion-front toads; and (iii) distinctive (active, fast-growing) phenotypes of the invasion-front toads. Nutritional benefits to individuals in the invasion vanguard (whether because of higher prey availability, or lower pathogen levels) thus may have conferred a selective advantage to accelerated dispersal in this system.
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An application of item response theory to fMRI data: prospects and pitfalls.
Psychiatry Res
PUBLISHED: 01-11-2013
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When using functional brain imaging to study neuropsychiatric patients an important challenge is determining whether the imaging task assesses individual differences with equal precision in healthy control and impaired patient groups. Classical test theory (CTT) requires separate reliability studies of patients and controls to determine equivalent measurement precision with additional studies to determine measurement precision for different levels of disease severity. Unlike CTT, item response theory (IRT) provides estimates of measurement error for different levels of ability, without the need for separate studies, and can determine if different tests are equivalently difficult when investigating differential deficits between groups. To determine the potential value of IRT in functional brain imaging, IRT was applied to behavioral data obtained during a multi-center functional MRI (fMRI) study of working memory (WM). Average item difficulty was approximately one standard deviation below the ability scale mean, supporting the tasks sensitivity to individual differences within the ability range of patients with WM impairment, but not within the range of most controls. The correlation of IRT estimated ability with fMRI activation during the task recognition period supported the linkage of the latent IRT scale to brain activation data. IRT can meaningfully contribute to the design of fMRI tasks.
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Sleep and circadian rhythm dysregulation in schizophrenia.
Prog. Neuropsychopharmacol. Biol. Psychiatry
PUBLISHED: 01-11-2013
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Sleep-onset and maintenance insomnia is a common symptom in schizophrenic patients regardless of either their medication status (drug-naive or previously treated) or the phase of the clinical course (acute or chronic). Regarding sleep architecture, the majority of studies indicate that non-rapid eye movement (NREM), N3 sleep and REM sleep onset latency are reduced in schizophrenia, whereas REM sleep duration tends to remain unchanged. Many of these sleep disturbances in schizophrenia appear to be caused by abnormalities of the circadian system as indicated by misalignments of the endogenous circadian cycle and the sleep-wake cycle. Circadian disruption, sleep onset insomnia and difficulties in maintaining sleep in schizophrenic patients could be partly related to a presumed hyperactivity of the dopaminergic system and dysfunction of the GABAergic system, both associated with core features of schizophrenia and with signaling in sleep and wake promoting brain regions. Since multiple neurotransmitter systems within the CNS can be implicated in sleep disturbances in schizophrenia, the characterization of the neurotransmitter systems involved remains a challenging dilemma.
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A Review of Traditional and Novel Treatments for Seizures in Autism Spectrum Disorder: Findings from a Systematic Review and Expert Panel.
Front Public Health
PUBLISHED: 01-01-2013
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Despite the fact that seizures are commonly associated with autism spectrum disorder (ASD), the effectiveness of treatments for seizures has not been well studied in individuals with ASD. This manuscript reviews both traditional and novel treatments for seizures associated with ASD. Studies were selected by systematically searching major electronic databases and by a panel of experts that treat ASD individuals. Only a few anti-epileptic drugs (AEDs) have undergone carefully controlled trials in ASD, but these trials examined outcomes other than seizures. Several lines of evidence point to valproate, lamotrigine, and levetiracetam as the most effective and tolerable AEDs for individuals with ASD. Limited evidence supports the use of traditional non-AED treatments, such as the ketogenic and modified Atkins diet, multiple subpial transections, immunomodulation, and neurofeedback treatments. Although specific treatments may be more appropriate for specific genetic and metabolic syndromes associated with ASD and seizures, there are few studies which have documented the effectiveness of treatments for seizures for specific syndromes. Limited evidence supports l-carnitine, multivitamins, and N-acetyl-l-cysteine in mitochondrial disease and dysfunction, folinic acid in cerebral folate abnormalities and early treatment with vigabatrin in tuberous sclerosis complex. Finally, there is limited evidence for a number of novel treatments, particularly magnesium with pyridoxine, omega-3 fatty acids, the gluten-free casein-free diet, and low-frequency repetitive transcranial magnetic simulation. Zinc and l-carnosine are potential novel treatments supported by basic research but not clinical studies. This review demonstrates the wide variety of treatments used to treat seizures in individuals with ASD as well as the striking lack of clinical trials performed to support the use of these treatments. Additional studies concerning these treatments for controlling seizures in individuals with ASD are warranted.
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Larger body size at metamorphosis enhances survival, growth and performance of young cane toads (Rhinella marina).
PLoS ONE
PUBLISHED: 01-01-2013
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Body size at metamorphosis is a key trait in species (such as many anurans) with biphasic life-histories. Experimental studies have shown that metamorph size is highly plastic, depending upon larval density and environmental conditions (e.g. temperature, food supply, water quality, chemical cues from conspecifics, predators and competitors). To test the hypothesis that this developmental plasticity is adaptive, or to determine if inducing plasticity can be used to control an invasive species, we need to know whether or not a metamorphosing anurans body size influences its subsequent viability. For logistical reasons, there are few data on this topic under field conditions. We studied cane toads (Rhinella marina) within their invasive Australian range. Metamorph body size is highly plastic in this species, and our laboratory studies showed that larger metamorphs had better locomotor performance (both on land and in the water), and were more adept at catching and consuming prey. In mark-recapture trials in outdoor enclosures, larger body size enhanced metamorph survival and growth rate under some seasonal conditions. Larger metamorphs maintained their size advantage over smaller siblings for at least a month. Our data support the critical but rarely-tested assumption that all else being equal, larger body size at metamorphosis is likely to enhance an individuals long term viability. Thus, manipulations to reduce body size at metamorphosis in cane toads may help to reduce the ecological impact of this invasive species.
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The Columbia-Suicide Severity Rating Scale: initial validity and internal consistency findings from three multisite studies with adolescents and adults.
Am J Psychiatry
PUBLISHED: 12-24-2011
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Research on suicide prevention and interventions requires a standard method for assessing both suicidal ideation and behavior to identify those at risk and to track treatment response. The Columbia-Suicide Severity Rating Scale (C-SSRS) was designed to quantify the severity of suicidal ideation and behavior. The authors examined the psychometric properties of the scale.
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Rescuers may vary their side of approach to a casualty without impact on cardiopulmonary resuscitation performance.
Emerg Med J
PUBLISHED: 12-08-2011
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To determine whether cardiopulmonary resuscitation (CPR) performance is influenced by a rescuers preferred side of approach.
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Therapeutic potential of melatonin and its analogs in Parkinsons disease: focus on sleep and neuroprotection.
Ther Adv Neurol Disord
PUBLISHED: 10-20-2011
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Sleep disorders constitute major nonmotor features of Parkinsons disease (PD) that have a substantial effect on patients quality of life and can be related to the progression of the neurodegenerative disease. They can also serve as preclinical markers for PD, as it is the case for rapid eye movement (REM)-associated sleep behavior disorder (RBD). Although the etiology of sleep disorders in PD remains undefined, the assessment of the components of the circadian system, including melatonin secretion, could give therapeutically valuable insight on their pathophysiopathology. Melatonin is a regulator of the sleep/wake cycle and also acts as an effective antioxidant and mitochondrial function protector. A reduction in the expression of melatonin MT(1) and MT(2) receptors has been documented in the substantia nigra of PD patients. The efficacy of melatonin for preventing neuronal cell death and for ameliorating PD symptoms has been demonstrated in animal models of PD employing neurotoxins. A small number of controlled trials indicate that melatonin is useful in treating disturbed sleep in PD, in particular RBD. Whether melatonin and the recently developed melatonergic agents (ramelteon, tasimelteon, agomelatine) have therapeutic potential in PD is also discussed.
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Melatonin and its analogs in insomnia and depression.
J. Pineal Res.
PUBLISHED: 09-23-2011
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Benzodiazepine sedative-hypnotic drugs are widely used for the treatment of insomnia. Nevertheless, their adverse effects, such as next-day hangover, dependence and impairment of memory, make them unsuitable for long-term treatment. Melatonin has been used for improving sleep in patients with insomnia mainly because it does not cause hangover or show any addictive potential. However, there is a lack of consistency on its therapeutic value (partly because of its short half-life and the small quantities of melatonin employed). Thus, attention has been focused either on the development of more potent melatonin analogs with prolonged effects or on the design of slow release melatonin preparations. The MT(1) and MT(2) melatonergic receptor ramelteon was effective in increasing total sleep time and sleep efficiency, as well as in reducing sleep latency, in insomnia patients. The melatonergic antidepressant agomelatine, displaying potent MT(1) and MT(2) melatonergic agonism and relatively weak serotonin 5HT(2C) receptor antagonism, was found effective in the treatment of depressed patients. However, long-term safety studies are lacking for both melatonin agonists, particularly considering the pharmacological activity of their metabolites. In view of the higher binding affinities, longest half-life and relative higher potencies of the different melatonin agonists, studies using 2 or 3mg/day of melatonin are probably unsuitable to give appropriate comparison of the effects of the natural compound. Hence, clinical trials employing melatonin doses in the range of 50-100mg/day are warranted before the relative merits of the melatonin analogs versus melatonin can be settled.
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Characteristics of individuals who make impulsive suicide attempts.
J Affect Disord
PUBLISHED: 08-18-2011
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Previous research has identified only a few variables that have been associated with making an impulsive suicide attempt. The aim of the current study was to compare individuals who made an impulsive suicide attempt with those who made a premeditated attempt on both previously examined and novel characteristics.
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Evaluation of blood antioxidant defense and apoptosis in peripheral lymphocytes on exogenous administration of pineal proteins and melatonin in rats.
J. Physiol. Biochem.
PUBLISHED: 07-23-2011
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In view of the significant health impact of oxidative stress and apoptosis dysfunction, and further, because of suggestions that administration of antioxidants might reduce apoptosis rate through up-regulation of body antioxidant defense systems, therefore the purpose of this study was to compare the effect of buffalo (Bubalus bubalis) pineal proteins (PP at 100 ?g/kg BW, i.p.) with melatonin (MEL at 10 mg/kg BW, i.p.) on blood (erythrocytes) antioxidant defense system and apoptosis in isolated peripheral blood lymphocytes of female Wistar albino rats. The cell viability index (%) and apoptosis index (%), which are directly related to the apoptosis rate of the cells, were used as dependent measures for inferring PP and MEL activity. The total cell viability index did not differ between rats treated with MEL and PP from control animals. The percentage of apoptotic cell death through fluorescence microscopy also did not change in MEL and PP groups as compared with control. DNA fragmentation as an index of apoptosis was detected with propidium iodide staining and assessed by flow cytometry. Pineal proteins and MEL administration caused significant (p?
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A guide for the assessment and treatment of suicidal patients with traumatic brain injuries.
J Head Trauma Rehabil
PUBLISHED: 07-08-2011
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People with traumatic brain injuries (TBIs) are at elevated risk for suicide. Postinjury cognitive limitations, personality factors, and psychological problems may independently or in conjunction with preinjury correlates contribute to suicidal thoughts and behaviors. Rehabilitation practitioners can best serve the needs of this high-risk population by increasing their knowledge and competence in evidence-informed approaches to suicide prevention. This article provides a review of suicide nomenclature, epidemiology, risk and protective factors, as well as evidence-informed assessment, management, and treatment practices for suicidal patients. The science of clinical practice in the area of rehabilitation and suicide prevention is in its infancy. Practitioners who provide treatment for suicidal patients with TBI are encouraged to adapt and individualize existing evidence-informed suicide assessment and prevention practices for implementation within their settings. Each patient with a TBI who endorses suicidal thoughts and/or behaviors presents a complex array of clinical challenges associated with the nature of his or her brain injury, preinjury, and postinjury functioning. Clinical as well as research recommendations are provided in the context of an understanding of such challenges and an overriding objective of minimizing suicide risk during the recovery process and maximizing treatment gains.
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Microarray assessment of methylation in individual mouse blastocyst stage embryos shows that in vitro culture may have widespread genomic effects.
Hum. Reprod.
PUBLISHED: 06-17-2011
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Although assisted reproductive technology (ART) is reported to result in abnormal genomic imprinting and/or altered genomic methylation, few if any studies have used high-throughput methods to analyze genomic methylation in ART embryos. We hypothesized that a microarray-based assessment of genomic methylation could be used to reveal differences between ART and normal preimplantation embryos.
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Using combined morphological, allometric and molecular approaches to identify species of the genus Raillietiella (Pentastomida).
PLoS ONE
PUBLISHED: 06-14-2011
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Taxonomic studies of parasites can be severely compromised if the host species affects parasite morphology; an uncritical analysis might recognize multiple taxa simply because of phenotypically plastic responses of parasite morphology to host physiology. Pentastomids of the genus Raillietiella are endoparasitic crustaceans primarily infecting the respiratory system of carnivorous reptiles, but also recorded from bufonid anurans. The delineation of pentastomids at the generic level is clear, but the taxonomic status of many species is not. We collected raillietiellids from lungs of the invasive cane toad (Rhinella marina), the invasive Asian house gecko (Hemidactylus frenatus), and a native tree frog (Litoria caerulea) in tropical Australia, and employed a combination of genetic analyses, and traditional and novel morphological methods to clarify their identity. Conventional analyses of parasite morphology (which focus on raw values of morphological traits) revealed two discrete clusters in terms of pentastome hook size, implying two different species of pentastomes: one from toads and a tree frog (Raillietiella indica) and another from lizards (Raillietiella frenatus). However, these clusters disappeared in allometric analyses that took pentastome body size into account, suggesting that only a single pentastome taxon may be involved. Our molecular data revealed no genetic differences between parasites in toads versus lizards, confirming that there was only one species: R. frenatus. This pentastome (previously known only from lizards) clearly is also capable of maturing in anurans. Our analyses show that the morphological features used in pentastomid taxonomy change as the parasite transitions through developmental stages in the definitive host. To facilitate valid descriptions of new species of pentastomes, future taxonomic work should include both morphological measurements (incorporating quantitative measures of body size and hook bluntness) and molecular data.
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The ecological impact of invasive cane toads on tropical snakes: field data do not support laboratory-based predictions.
Ecology
PUBLISHED: 05-31-2011
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Predicting which species will be affected by an invasive taxon is critical to developing conservation priorities, but this is a difficult task. A previous study on the impact of invasive cane toads (Bufo marinus) on Australian snakes attempted to predict vulnerability a priori based on the assumptions that any snake species that eats frogs, and is vulnerable to toad toxins, may be at risk from the toad invasion. We used time-series analyses to evaluate the accuracy of that prediction, based on >3600 standardized nocturnal surveys over a 138-month period on 12 species of snakes and lizards on a floodplain in the Australian wet-dry tropics, bracketing the arrival of cane toads at this site. Contrary to prediction, encounter rates with most species were unaffected by toad arrival, and some taxa predicted to be vulnerable to toads increased rather than declined (e.g., death adder Acanthophis praelongus; Childrens python Antaresia childreni). Indirect positive effects of toad invasion (perhaps mediated by toad-induced mortality of predatory varanid lizards) and stochastic weather events outweighed effects of toad invasion for most snake species. Our study casts doubt on the ability of a priori desktop studies, or short-term field surveys, to predict or document the ecological impact of invasive species.
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Voxel-based morphometry of patients with schizophrenia or bipolar I disorder: a matched control study.
Psychiatry Res
PUBLISHED: 05-06-2011
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Controlled trials provide critical tests of hypotheses generated by meta-analyses. Two recent meta-analyses have reported that gray matter volumes of schizophrenia and bipolar I patients differ in the amygdala, hippocampus, or perigenual anterior cingulate. The present magnetic resonance imaging study tested these hypotheses in a cross-sectional voxel-based morphometry (VBM) design of 17 chronic schizophrenia and 15 chronic bipolar patients and 21 healthy subjects matched for age, gender and duration of illness. Whole brain gray matter volume of both the schizophrenia and bipolar groups was smaller than among healthy control subjects. Regional voxel-wise comparisons showed that gray matter volume was smallest within frontal and temporal regions of both patient groups. Region of interest analyses found moderately large to large differences between schizophrenia and healthy subjects in the amygdala and hippocampus. There were no group differences in the perigenual anterior cingulate. When schizophrenia and bipolar groups were directly compared, the schizophrenia group showed smaller gray matter volumes in right subcortical regions involving the right hippocampus, putamen, and amygdala. The hippocampal and amygdala findings confirm predictions derived from recent meta-analyses. These structural abnormalities may be important factors in the differential manifestations of these two functional psychotic disorders.
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Phylogeny, adaptive radiation, and historical biogeography in Bromeliaceae: insights from an eight-locus plastid phylogeny.
Am. J. Bot.
PUBLISHED: 05-02-2011
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Bromeliaceae form a large, ecologically diverse family of angiosperms native to the New World. We use a bromeliad phylogeny based on eight plastid regions to analyze relationships within the family, test a new, eight-subfamily classification, infer the chronology of bromeliad evolution and invasion of different regions, and provide the basis for future analyses of trait evolution and rates of diversification.
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Assessing conservation opportunity on private land: socio-economic, behavioral, and spatial dimensions.
J. Environ. Manage.
PUBLISHED: 03-28-2011
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This study presents a method for assessing conservation opportunity on private land based on landholders socio-economic, behavioral, and farm characteristics. These characteristics include age, gender, education, level of off-farm income, farm size, proportion of remnant native vegetation on-farm, and ecological value of native vegetation on-farm. A sample of landholders who own greater than 2 ha of land in the South Australian Murray-Darling Basin region were sent a mail-based survey about their values and preferences for environmental management (N = 659, 52% response). Cross-tabulations and ANOVA statistical analysis techniques were used to compare the socio-economic attributes across three landholder classes: disengaged, moderately engaged, and highly engaged in native vegetation planting. Results indicate that highly engaged landholders were more likely to be female, formally educated, hobby farmers who managed small parcels of land and have high off-farm incomes, whereas disengaged landholders held significantly stronger farming connections (more farming experience, family have lived on the farm for more generations). Spatial analysis revealed area-specific differences in conservation opportunity and conservation priority. In some areas, properties of high ecological value were managed by highly engaged landholders, but nearby properties of high value were managed by moderately engaged or disengaged landholders. Environmental managers therefore cannot assume areas of high conservation priority will be areas of high conservation opportunity. At the regional scale, the potential for revegetation seems most promising within the moderately engaged landholder group considering the vast amount of land managed by this group in areas of high ecological value, particularly within the less represented Mallee and Coorong and Rangelands sub-regions. We suggest that incentive schemes which purchase conservation need to be targeted at disengaged landholders; mentoring schemes led by commercial farmers highly engaged in native vegetation planting should be directed at moderately engaged landholders, and; awards programs which acknowledge conservation successes should be targeted at highly engaged landholders.
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Melatonin agonists in primary insomnia and depression-associated insomnia: are they superior to sedative-hypnotics?
Prog. Neuropsychopharmacol. Biol. Psychiatry
PUBLISHED: 03-22-2011
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Current pharmacological treatment of insomnia involves the use of sedative-hypnotic benzodiazepine and non-benzodiazepine drugs. Although benzodiazepines improve sleep, their multiple adverse effects hamper their application. Adverse effects include impairment of memory and cognitive functions, next-day hangover and dependence. Non-benzodiazepines are effective for initiating sleep but are not as effective as benzodiazepines for improving sleep quality or efficiency. Furthermore, their prolonged use produces adverse effects similar to those observed with benzodiazepines. Inasmuch as insomnia may be associated with decreased nocturnal melatonin, administration of melatonin is a strategy that has been increasingly used for treating insomnia. Melatonin can be effective for improving sleep quality without the adverse effects associated with hypnotic-sedatives. Ramelteon, a synthetic analog of melatonin which has a longer half life and a stronger affinity for MT1 and MT2 melatonergic receptors, has been reportedly effective for initiating and improving sleep in both adult and elderly insomniacs without showing hangover, dependence, or cognitive impairment. Insomnia is also a major complaint among patients suffering from depressive disorders and is often aggravated by conventional antidepressants especially the specific serotonin reuptake inhibitors. The novel antidepressant agomelatine, a dual action agent with affinity for melatonin MT1 and MT2 receptors and 5-HT2c antagonistic properties, constitutes a new approach to the treatment of major depressive disorders. Agomelatine ameliorates the symptoms of depression and improves the quality and efficiency of sleep. Taken together, the evidence indicates that MT1/MT2 receptor agonists like ramelteon or agomelatine may be valuable pharmacological tools for insomnia and for depression-associated insomnia.
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An evolutionary process that assembles phenotypes through space rather than through time.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 03-21-2011
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In classical evolutionary theory, traits evolve because they facilitate organismal survival and/or reproduction. We discuss a different type of evolutionary mechanism that relies upon differential dispersal. Traits that enhance rates of dispersal inevitably accumulate at expanding range edges, and assortative mating between fast-dispersing individuals at the invasion front results in an evolutionary increase in dispersal rates in successive generations. This cumulative process (which we dub "spatial sorting") generates novel phenotypes that are adept at rapid dispersal, irrespective of how the underlying genes affect an organisms survival or its reproductive success. Although the concept is not original with us, its revolutionary implications for evolutionary theory have been overlooked. A range of biological phenomena (e.g., acceleration of invasion fronts, insular flightlessness, preadaptation) may have evolved via spatial sorting as well as (or rather than) by natural selection, and this evolutionary mechanism warrants further study.
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Effects of biologically-active chemical mixtures on fish in a wastewater-impacted urban stream.
Sci. Total Environ.
PUBLISHED: 02-05-2011
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Stream flow in urban aquatic ecosystems often is maintained by water-reclamation plant (WRP) effluents that contain mixtures of natural and anthropogenic chemicals that persist through the treatment processes. In effluent-impacted streams, aquatic organisms such as fish are continuously exposed to biologically-active chemicals throughout their life cycles. The North Shore Channel of the Chicago River (Chicago, Illinois) is part of an urban ecosystem in which >80% of the annual flow consists of effluent from the North Side WRP. In this study, multiple samplings of the effluent and stream water were conducted and fish (largemouth bass and carp) were collected on 2 occasions from the North Shore Channel. Fish also were collected once from the Outer Chicago Harbor in Lake Michigan, a reference site not impacted by WRP discharges. Over 100 organic chemicals with differing behaviors and biological effects were measured, and 23 compounds were detected in all of the water samples analyzed. The most frequently detected and highest concentration (>100?g/L) compounds were ethylenediaminetetraacetic acid and 4-nonylphenolmono-to-tetraethoxycarboxylic acids. Other biologically-active chemicals including bisphenol A, 4-nonylphenol, 4-nonylphenolmono-to-tetraethoxylates, 4-tert-octylphenol, and 4-tert-octylphenolmono-to-tetraethoxylates were detected at lower concentrations (<5?g/L). The biogenic steroidal hormones 17?-estradiol, estrone, testosterone, 4-androstene-3,17-dione, and cis-androsterone were detected at even lower concentrations (<0.005?g/L). There were slight differences in concentrations between the North Side WRP effluent and the North Shore Channel, indicating minimal in-stream attenuation. Fish populations are continuously exposed to mixtures of biologically-active chemicals because of the relative persistency of the chemicals with respect to stream hydraulic residence time, and the lack of a fresh water source for dilution. The majority of male fish exhibited vitellogenin induction, a physiological response consistent with exposure to estrogenic compounds. Tissue-level signs of reproductive disruption, such as ovatestis, were not observed.
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Variability in the definition and reporting of adverse events in suicide prevention trials: an examination of the issues and a proposed solution.
Arch Suicide Res
PUBLISHED: 02-05-2011
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Adverse events (AEs) and serious adverse events (SAEs) are important outcomes of any intervention study yet are under-researched. Vague and variable definitions and substantial underreporting make comparisons of risk between studies difficult and evaluation of the safety of a particular intervention almost impossible. These realities may deter researchers from studying at-risk populations. Suicidal behavior is an adverse event in any study, and potentially a very serious one. Thus the issues of reporting and definition are particularly salient for researchers who work with populations at risk for suicidal behavior, especially when the suicidal behavior is the outcome of interest. We conducted a qualitative study with experienced suicide researchers and intervention experts to delineate the issues related to reporting serious adverse events faced by investigators conducting trials in suicide prevention. Participants from multiple sites were interviewed by phone, interviews transcribed and coded for definition and reporting issues and suggested solutions. A narrative synthesis was prepared and validated by all participants. Participants highlighted the difficulties in defining AEs and SAEs and stressed the importance and complexity of ensuring the AE was related to the study and reported properly, and were in agreement about the consequences of AEs to both institutions and individuals. Participants identified the need for the development of clear and consistent AE definitions and reporting requirements. Clear and consistently applied definitions of adverse and serious adverse events and reporting requirements would enhance the comparability of intervention studies in suicidal populations.
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Participation bias among suicidal adults in a randomized controlled trial.
Suicide Life Threat Behav
PUBLISHED: 02-02-2011
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Although individuals who attempt suicide have poor compliance rates with treatment recommendations, the nature and degree of participation bias in clinical treatment research among these individuals is virtually unknown. The purpose of this study was to examine participation bias by comparing the demographic and diagnostic characteristics of adult suicide attempters who participated in a randomized controlled trial to a sample of nonparticipants. Results indicated that males and individuals with a diagnosis of substance abuse or dependence were more likely to be participants in the randomized controlled trial. The implications of these findings for suicide intervention research are discussed.
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Cerebral epiphyseal proteins and melatonin modulate the hepatic and renal antioxidant defense of rats.
Int J Nephrol
PUBLISHED: 01-17-2011
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The cerebral epiphysis (pineal gland) secrets melatonin and number of other proteins and peptides. It was thus hypothesized that antioxidant properties of epiphyseal proteins and melatonin could potentially benefit from exogenous therapies. In view of the therapeutic potential of these proteins, the present experiment was conducted to investigate the effect of buffalo epiphyseal proteins (BEP, at 100??g/kg BW, i.p.) and melatonin (MEL, at 10?mg/kg BW, i.p) on changes in hepatic and renal antioxidant enzymes of adult female Wistar rats. Buffalo epiphyseal proteins significantly (P < .05) increased hepatic lipid peroxidation (LPO), superoxide dismutase (SOD), glutathione reductase (GR), glutathione peroxidase (GPx), reduced glutathione (GSH), and renal LPO, catalase (CAT), GR, GSH, GPx levels as compared to control animals. Similarly, MEL treatment significantly (P < .05) up-regulated hepatic SOD and GPx activity, whereas CAT, GR, GPx, and GSH levels in renal tissues were increased while SOD and LPO remained unaffected. Buffalo epiphyseal protein treatment produced greater effects on hepatic GPx and renal CAT and GSH levels than did MEL. These findings support the conclusion that buffalo epiphyseal proteins and melatonin activate a number of antioxidant mechanisms in hepatic and renal tissues.
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Predictors of suicide relative to other deaths in patients with suicide attempts and suicide ideation: a 30-year prospective study.
J Affect Disord
PUBLISHED: 01-08-2011
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Although there is a large literature that prospectively examines predictors of suicide, low base rates of suicide and imprecision of measurement hinder definitive conclusions from being drawn.
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Suicide and suicide risk in lesbian, gay, bisexual, and transgender populations: review and recommendations.
J Homosex
PUBLISHED: 01-08-2011
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Despite strong indications of elevated risk of suicidal behavior in lesbian, gay, bisexual, and transgender people, limited attention has been given to research, interventions or suicide prevention programs targeting these populations. This article is a culmination of a three-year effort by an expert panel to address the need for better understanding of suicidal behavior and suicide risk in sexual minority populations, and stimulate the development of needed prevention strategies, interventions and policy changes. This article summarizes existing research findings, and makes recommendations for addressing knowledge gaps and applying current knowledge to relevant areas of suicide prevention practice.
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Pharmacotherapy of insomnia with ramelteon: safety, efficacy and clinical applications.
J Cent Nerv Syst Dis
PUBLISHED: 01-01-2011
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Ramelteon is a tricyclic synthetic analog of melatonin that acts specifically on MT1 and MT2 melatonin receptors. Ramelteon is the first melatonin receptor agonist approved by the Food and Drug Administration (FDA) for the treatment of insomnia characterized by sleep onset difficulties. Ramelteon is both a chronobiotic and a hypnotic that has been shown to promote sleep initiation and maintenance in various preclinical and in clinical trials. The efficacy and safety of ramelteon in patients with chronic insomnia was initially confirmed in short-term placebo-controlled trials. These showed little evidence of next-day residual effects, withdrawal symptoms or rebound insomnia. Other studies indicated that ramelteon lacked abuse potential and had a minimal risk of producing dependence or adverse effects on cognitive or psychomotor performance. A 6-month placebo-controlled international study and a 1-year open-label study in the USA demonstrated that ramelteon was effective and well tolerated. Other potential off-label uses of ramelteon include circadian rhythm sleep disorders such as shift-work and jet lag. At the present time the drug should be cautiously prescribed for short-term treatment only.
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Melatonin--a pleiotropic, orchestrating regulator molecule.
Prog. Neurobiol.
PUBLISHED: 10-12-2010
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Melatonin, the neurohormone of the pineal gland, is also produced by various other tissues and cells. It acts via G protein-coupled receptors expressed in various areas of the central nervous system and in peripheral tissues. Parallel signaling mechanisms lead to cell-specific control and recruitment of downstream factors, including various kinases, transcription factors and ion channels. Additional actions via nuclear receptors and other binding sites are likely. By virtue of high receptor density in the circadian pacemaker, melatonin is involved in the phasing of circadian rhythms and sleep promotion. Additionally, it exerts effects on peripheral oscillators, including phase coupling of parallel cellular clocks based on alternate use of core oscillator proteins. Direct central and peripheral actions concern the up- or downregulation of various proteins, among which inducible and neuronal NO synthases seem to be of particular importance for antagonizing inflammation and excitotoxicity. The methoxyindole is also synthesized in several peripheral tissues, so that the total content of tissue melatonin exceeds by far the amounts in the circulation. Emerging fields in melatonin research concern receptor polymorphism in relation to various diseases, the control of sleep, the metabolic syndrome, weight control, diabetes type 2 and insulin resistance, and mitochondrial effects. Control of electron flux, prevention of bottlenecks in the respiratory chain and electron leakage contribute to the avoidance of damage by free radicals and seem to be important in neuroprotection, inflammatory diseases and, presumably, aging. Newly discovered influences on sirtuins and downstream factors indicate that melatonin has a role in mitochondrial biogenesis.
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Functional brain imaging in schizophrenia: selected results and methods.
Curr Top Behav Neurosci
PUBLISHED: 08-25-2010
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Functional brain imaging studies of patients with schizophrenia may be grouped into those that assume that the signs and symptoms of schizophrenia are due to disordered circuitry within a critical brain region and studies that assume that the signs and symptoms are due to disordered connections among brain regions. Studies have investigated the disordered functional brain anatomy of both the positive and negative symptoms of schizophrenia. Studies of spontaneous hallucinations find that although hallucinations are associated with abnormal brain activity in primary and secondary sensory areas, disordered brain activation associated with hallucinations is not limited to sensory systems. Disordered activation in non-sensory regions appear to contribute to the emotional strength and valence of hallucinations, to be a factor underlying an inability to distinguish ongoing mental processing from memories, and to reflect the brains attempt to modulate the intensity of hallucinations and resolve conflicts with other processing demands. Brain activation studies support the view that auditory/verbal hallucinations are associated with an impaired ability of internal speech plans to modulate neural activation in sensory language areas. In early studies, negative symptoms of schizophrenia were hypothesized to be associated with impaired function in frontal brain areas. In support of this hypothesis meta-analytical studies have found that resting blood flow or metabolism in frontal cortex is reduced in schizophrenia, though the magnitude of the effect is only small to moderate. Brain activation studies of working memory (WM) functioning are typically associated with large effect sizes in the frontal cortex, whereas studies of functions other than WM generally reveal smaller effects. Findings from some functional connectivity studies have supported the hypothesis that schizophrenia patients experience impaired functional connections between frontal and temporal cortex, although the nature of the disordered connectivity is complex. More recent studies have used functional brain imaging to study neural compensation in schizophrenia, to serve as endophenotypes in genetic studies and to provide biomarkers in drug development studies. These emerging trends in functional brain imaging research are likely to help stimulate the development of a general neurobiological theory of the complex symptoms of schizophrenia.
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Life-history evolution in range-shifting populations.
Ecology
PUBLISHED: 06-30-2010
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Most evolutionary theory does not deal with populations expanding or contracting in space. Invasive species, climate change, epidemics, and the breakdown of dispersal barriers, however, all create populations in this kind of spatial disequilibrium. Importantly, spatial disequilibrium can have important ecological and evolutionary outcomes. During continuous range expansion, for example, populations on the expanding front experience novel evolutionary pressures because frontal populations are assorted by dispersal ability and have a lower density of conspecifics than do core populations. These conditions favor the evolution of traits that increase rates of dispersal and reproduction. Additionally, lowered density on the expanding front eventually frees populations on the expanding edge from specialist, coevolved enemies, permitting higher investment into traits associated with dispersal and reproduction rather than defense against pathogens. As a result, the process of range expansion drives rapid life-history evolution, and this seems to occur despite ongoing serial founder events that have complex effects on genetic diversity at the expanding front. Traits evolving on the expanding edge are smeared across the landscape as the front moves through, leaving an ephemeral signature of range expansion in the life-history traits of a species across its newly colonized range. Recent studies suggest that such nonequilibrium processes during recent population history may have contributed to many patterns usually ascribed to evolutionary forces acting in populations at spatial equilibrium.
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Influence of lung parasites on the growth rates of free-ranging and captive adult cane toads.
Oecologia
PUBLISHED: 06-22-2010
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Many parasites affect the viability of their hosts, but detailed studies combining empirical data from both the field and the laboratory are limited. Consequently, the nature and magnitude of such effects are poorly known for many important host-parasite systems, including macroparasites of amphibians. We examined the effects of lungworm (Rhabdias pseudosphaerocephala) infections in cane toads (Bufo marinus) within their invasive Australian range. The host-specificity of this parasite suggests that it might serve as a biological control agent for toads in Australia, if infection proves to reduce toad viability. Mark-recapture studies in the field (near Darwin, Northern Territory) revealed lowered growth rates in infected adult toads when compared to uninfected toads, and a laboratory experiment confirmed causality: experimental infection with R. pseudosphaerocephala reduce toad growth rates. In combination with previous work on the current host-parasite system, it is now evident that nematode lungworms reduce the viability of both newly metamorphosed and adult cane toads, and do so in the field as well as in the laboratory. Rhabdias pseudosphaerocephala may be a valuable component of a biological control strategy for cane toads in Australia.
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Jet lag, circadian rhythm sleep disturbances, and depression: the role of melatonin and its analogs.
Adv Ther
PUBLISHED: 06-21-2010
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Traveling through several time zones results in a constellation of symptoms known as jet lag. These include reduced alertness, daytime fatigue, loss of appetite, reduced cognitive skills, and disruption of the sleep/wake cycle. In susceptible air travel passengers, jet lag may exacerbate affective illness and result in psychiatric morbidity. Dysregulation of circadian rhythms and melatonin secretion represent the common underlying factor in jet lag and other circadian disorders. Recent studies have established the effectiveness of strategically timed administration of melatonin and appropriate timed exposure to environmental schedules including light in counteracting the dysregulation (chronobiologic actions). With the introduction of melatonergic agonists such as ramelteon and tasimelteon, which have both a stronger affinity for MT? and MT? melatonin receptors and a longer half-life, new therapeutic options now exist for treating the sleep disturbances associated with jet lag. The melatonin analogs are unique inasmuch as they can also enhance daytime alertness. The recently introduced melatonergic antidepressant agomelatine, which has established its supremacy over other antidepressants in having a significant chronobiologic activity, represents a good choice for treating depressive symptoms that are associated with jet lag.
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Melatonin as a therapeutic tool in ophthalmology: implications for glaucoma and uveitis.
J. Pineal Res.
PUBLISHED: 05-13-2010
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Several lines of evidence support the view that increased free radical generation and altered nitric oxide (NO) metabolism play a role in the pathogenesis of highly prevalent ocular diseases, such as glaucoma and uveitis. Data are discussed indicating that melatonin, being an efficient antioxidant that displays antinitridergic properties, has a promising role in the treatment of these ocular dysfunctions. Melatonin synthesis occurs in the eye of most species, and melatonin receptors are localized in different ocular structures. In view of the fact that melatonin lacks significant adverse collateral effects even at high doses, the application of melatonin could potentially protect ocular tissues by effectively scavenging free radicals and excessive amounts of NO generated in the glaucomatous or uveitic eye.
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Comparison of energy expenditure on a treadmill vs. an elliptical device at a self-selected exercise intensity.
J Strength Cond Res
PUBLISHED: 05-11-2010
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Treadmills (TM) and elliptical devices (EL) are popular forms of exercise equipment. The differences in the training stimulus presented by TM or EL are unknown. The purpose of this investigation was to evaluate oxygen consumption, energy expenditure, and heart rate on a TM or EL when persons exercise at the same perceived level of exertion. After measuring peak oxygen uptake (VO2peak) in 9 male and 9 female untrained college-aged participants, the subjects performed 2 separate 15-minute submaximal exercise tests on the TM and EL at a rating of perceived exertion (RPE) of 12-13. VO2peak was higher (p<0.05) in the males (48.6+/-1.5 vs. 45.2+/-1.6 ml/kg/min) than the females (41.7+/-1.8 vs. 38.8+/-2.2 ml/kg/min) for both TM and EL (means+/-standard error of the mean; for TM vs. EL respectively), but there were no differences in the measured VO2peak between TM or EL. During submaximal exercise there were no differences in RPE between TM and EL. Total oxygen consumption was higher (p<0.05) in males (30.8+/-2.2 vs. 34.9+/-2.2 L) than females (24.1+/-1.8 vs. 26.9+/-1.7 L) but did not differ between TM and EL. Energy expenditure was not different between TM (569+/-110 J) or EL (636+/-120 kJ). Heart rate was higher (p<0.05) on the EL (164+/-16 beats/min) compared to the TM (145+/-15 beats/min). When subjects exercise at the same RPE on TM or EL, oxygen consumption and energy expenditure are similar in spite of a higher heart rate on the EL. These data indicate that during cross training or noncompetition-specific exercise, an elliptical device is an acceptable alternative to a treadmill.
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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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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.