460 research outputs found

    Barking up the wrong biomarker? Correspondence to Shobeiri et al. (2022) “Serum and plasma levels of brain-derived neurotrophic factor in individuals with eating disorders (EDs): a systematic review and meta-analysis”

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    Despite intensified research efforts into the underlying (neuro-)biology of eating disorders (EDs), only few reliable biomarkers of diagnostic or prognostic value have been identified to date. One promising line of research has focused on the role of peripheral blood-based biomarkers as potential contributors to the complex pathophysiology of EDs. One such candidate marker is brain-derived neurotrophic factor (BDNF), a neurotrophin broadly implicated in neuronal plasticity and food-intake regulation. A growing number of studies have targeted BDNF in EDs; culminating in several recent well-powered and controlled case–control studies, comprehensive meta-analyses, and review articles. In the current correspondence, we aim to put the recent meta-analysis of Shobeiri et al. (J Eat Disord 10(1):105, 2022) into perspective and argue that the finding suggestive of lower BDNF concentrations across individuals with EDs in comparison to healthy controls needs to be interpreted with caution. While this finding is compatible with those from earlier meta-analyses, it may be biased due to several reasons; most notably by the applied study selection procedures, insufficient consideration of influential determinants of BDNF concentrations, and generalization of results across the ED spectrum without sufficient statistical power. Further controlled and comprehensive studies are necessary to establish BDNF as a clinically informative biomarker of EDs

    The Status of Wildlife Damage Compensation in China.

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    The conservation management of natural ecosystems in China has significantly improved in recent decades, resulting in the effective protection of wildlife and the restoration of habitats. With the rapid growth in wildlife populations and corresponding range expansions, incidents of human-wildlife conflict have notably increased across China. However, only a few studies have paid adequate attention to wildlife damage management and compensation. In our review, we focus on the foremost mitigation measure to combat human-wildlife conflict, i.e., compensation for damage caused by wildlife. We conducted a questionnaire survey and an in-depth review of the literature across 19 Chinese provinces and autonomous regions, resulting in a total of 78 relevant sources. We first introduce the concept of wildlife damage compensation in China, followed by a review of Chinese legislation and policies regarding wildlife damage compensation. We compiled a comprehensive list of nuisance species, and we showcase four case studies in which we exemplarily describe the current situation of wildlife damage compensation. We reflect on difficulties and challenges such as delayed damage assessments or compensation quotas that do not correspond to current market prices. Since local legislation is often insufficient or completely absent, we make suggestions on how to improve existing policies and compensation mechanisms

    Is Serum BDNF Altered in Acute, Short- and Long-Term Recovered Restrictive Type Anorexia Nervosa?

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    Brain-derived neurotrophic factor (BDNF), a neurotrophin involved in the regulation of food intake and body weight, has been implicated in the development and maintenance of Anorexia nervosa (AN). The majority of previous studies reported lower BDNF levels in acutely underweight AN patients (acAN) and increasing levels after weight rehabilitation. Here, we investigated serum BDNF concentrations in the largest known AN sample to date, both before and after weight restoration therapy. Serum BDNF was measured in 259 female volunteers: 77 in-patient acAN participants of the restrictive type (47 reassessed after short-term weight rehabilitation), 62 individuals long-term recovered from AN, and 120 healthy controls. We validated our findings in a post-hoc mega-analysis in which we reanalyzed combined data from the current sample and those from our previous study on BDNF in AN (combined sample: 389 participants). All analyses carefully accounted for known determinants of BDNF (age, sex, storage time of blood samples). We further assessed relationships with relevant clinical variables (body-mass-index, physical activity, symptoms). Contrary to our hypotheses, we found zero significant differences in either cross-sectional or longitudinal comparisons and no significant relationships with clinical variables. Together, our study suggests that BDNF may not be a reliable state- or trait-marker in AN after all

    Community structure and environmental determinants of the bacterial and fungal gut microflora in Hainan gibbons (Nomascus hainanus)

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    High-throughput sequencing technology was used to establish the OTU (Operational Taxonomic Units) composition and diversity of bacteria and fungi in the gut of three family groups of Hainan gibbons (Nomascus hainanus) in the Bawangling National Nature Reserve on Hainan Island, southern China. Firmicutes (47.23%) and Bacteroidetes (36.54%) predominated at the phylum level, while the predominant genera were Prevotella-7 (15.30%), Lachnospiraceae_NK3A20_group (12.49%), and uncultured_bacterium_f_Erysipelotrichaceae (11.79%). At the phylum level, the dominant fungi were Ascomycota (66.41%), as well as Hanseniaspora (23.33%), Schwanniomyces (13.44%), and Pichia (5.43%) at the genus level. We found significant differences in the bacterial OTU diversity (Shannon index) between family groups living in Tropical Lowland or Tropical Montane Rain Forest, compared to those inhabiting Tropical Montane Evergreen Forest at higher altitudes. Bacterial OTU community composition also differed between family groups, unraveling significant differences among the 30 most dominant bacterial core taxa. Furthermore, we unraveled a significant difference of OTU richness in the fungal microbiome (Chao 1) between family groups living at lower altitudes, i.e., Tropical Lowland or Tropical Montane Rain Forest and those inhabiting the Tropical Montane Evergreen Forest. Our analysis further indicated significant differences in the fungal OTU community composition between the three family groups, especially regarding the three most dominant fungal core taxa. Subsequently, two habitat factors, and nine environmental and anthropogenic variables were used to explore possible causes of disparity in the microbial flora of gibbon groups. A factor reduction procedure resulted into three principal components which were correlated to bacterial and fungal OTU richness and diversity using Spearman's rank-order correlations. Bacterial and fungal OTU diversity was high in areas of high altitude, steep slopes, high tree density, but low tree height, while high fungal OTU richness corresponded to high altitude habitats, i.e., in the Tropical Montane Evergreen Forest. Distance to human settlements and to the next water body showed no significant relation with bacterial and fungal richness and diversity

    Extrinsic factors, endocrine mechanisms, and behavioral indicators of migratory restlessness in wintering whooper swans (Cygnus cygnus).

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    Extrinsic factors, endocrine mechanisms, and behavioral indicators of migratory restlessness were studied in wintering whooper swans (Cygnus cygnus) in the Sanmenxia Swan National Wetland Park in western Henan Province, central China. First, the fecal glucocorticoid metabolite (FGM) concentration was established and related to mean air temperature or photo period (day length) using simple linear or non-linear regression models. After a model selection procedure, the best fitted model revealed that an increase of FGM concentration was associated with an increase in the squared mean air temperature (R2 = 0.88). Other models showed an increasing FGM concentration to correspond with increasing values of day length, squared day length, and mean air temperature-however without statistical support. In a second step, behavioral frequencies of seven behaviors were condensed into three behavioral principal components (PCs) using principal components analysis. Behavioral PCs largely corresponded to three activity phases described for wintering whooper swans in central China and were correlated with the FGM concentration using Spearman's rank-order correlations. Results revealed a significant correlation between FGM and behavioral PC2 (positive factor loadings from vigilance and preening, negative loading from foraging). Finally, we tested for an effect of behavioral PCs on changes in winter home range size using a set of multiple linear regression models. Results of averaged model parameter estimates showed only the behavioral PC3 (positive factor loadings from fighting and calling, negative loading from locomotion) had a marginal significant effect on home range size. Results confirmed findings of previous studies on migratory restlessness in whooper swans. However, due to the small sample size (N = 15 weeks) the effect of PC3 on home range size was weak and should be viewed with caution

    Stress distribution correlated with damage in duplex stainless steel studied by synchrotron diffraction during plastic necking

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    The goal of this work was the determination of lattice strains distribution in two phases of duplex steel during plastic necking. Subsequently, the stress heterogeneity in the neck was studied in order to determine the reason for the damage initiation and to verify the hypothesis that the damage begins in the ferritic phase. To do this, X-ray synchrotron radiation was used to scan the ‘in situ’ variation of the interplanar spacings along the necking zone for samples subjected to tensile loading. A self-consistent model and FEM simulation were applied for the experimental data interpretation. It was found that for advanced necking the phase lattice strains, especially those measured at some distance from the neck centre, show a large inversion of the loads localised in both phases compared to the undamaged state (the lattice strains in the ferrite become smaller than in the austenite). This effect indicates stress relaxation in the ferrite which is connected with the damage phenomenon. Correlation of the experimental results with the modelling shows that the value of von Mises stress is responsible for the initiation of the ferritic phase softening

    Prognostic factors for outcomes after whole-brain irradiation of brain metastases from relatively radioresistant tumors: a retrospective analysis

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    <p>Abstract</p> <p>Background</p> <p>This study investigated potential prognostic factors in patients treated with whole-brain irradiation (WBI) alone for brain metastases from relatively radioresistant tumors such as malignant melanoma, renal cell carcinoma, and colorectal cancer. Additionally, a potential benefit from escalating the radiation dose was investigated.</p> <p>Methods</p> <p>Data from 220 patients were retrospectively analyzed for overall survival and local control. Nine potential prognostic factors were evaluated: tumor type, WBI schedule, age, gender, Karnofsky performance score, number of brain metastases, extracerebral metastases, interval from diagnosis of cancer to WBI, and recursive partitioning analysis (RPA) class.</p> <p>Results</p> <p>Survival rates at 6 and 12 months were 32% and 19%, respectively. In the multivariate analysis, WBI doses >30 Gy (p = 0.038), KPS ≥70 (p < 0.001), only 1-3 brain metastases (p = 0.007), no extracerebral metastases (p < 0.001), and RPA class 1 (p < 0.001) were associated with improved survival. Local control rates at 6 and 12 months were 37% and 15%, respectively. In the multivariate analyses, KPS ≥70 (p < 0.001), only 1-3 brain metastases (p < 0.001), and RPA class 1 (p < 0.001) were associated with improved local control. In RPA class 3 patients, survival rates at 6 months were 10% (35 of 39 patients) after 10 × 3 Gy and 9% (2 of 23 patients) after greater doses, respectively (p = 0.98).</p> <p>Conclusions</p> <p>Improved outcomes were associated with WBI doses >30 Gy, better performance status, fewer brain metastases, lack of extracerebral metastases, and lower RPA class. Patients receiving WBI alone appear to benefit from WBI doses >30 Gy. However, such a benefit is limited to RPA class 1 or 2 patients.</p
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