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71.
72.
Peritoneal mesothelioma is a rare and sometimes lethal malignancy that presents a clinical challenge for both diagnosis and management. Recent studies have led to a better understanding of the molecular biology of peritoneal mesothelioma. Translation of the emerging data into better treatments and outcome is needed. From two patients with peritoneal mesothelioma, we derived whole genome sequences, RNA expression profiles, and targeted deep sequencing data. Molecular data were made available for translation into a clinical treatment plan. Treatment responses and outcomes were later examined in the context of molecular findings. Molecular studies presented here provide the first reported whole genome sequences of peritoneal mesothelioma. Mutations in known mesothelioma-related genes NF2, CDKN2A, LATS2, amongst others, were identified. Activation of MET-related signaling pathways was demonstrated in both cases. A hypermutated phenotype was observed in one case (434 vs. 18 single nucleotide variants) and was associated with a favourable outcome despite sarcomatoid histology and multifocal disease. This study represents the first report of whole genome analyses of peritoneal mesothelioma, a key step in the understanding and treatment of this disease.  相似文献   
73.
Phencyclidine (PCP; 20 micrograms in 0.5 microliter) was tested by local brain injection for neurochemical effects in the nucleus accumbens and striatum of rats. Changes in dopamine turnover could not be detected in postmortem tissue assays. In contrast, extracellular levels of dopamine significantly increased as measured by microdialysis in freely moving animals. PCP also increased extracellular levels of serotonin and decreased 3,4-dihydroxyphenylacetic acid (DOPAC), but did not change homovanillic acid (HVA) or 5-hydroxyindoleacetic acid (5HIAA). Microdialysis suggests that PCP acts in some dopamine terminal regions to increase extracellular dopamine and serotonin.  相似文献   
74.

Background

Copy number variants (CNVs), including deletions, amplifications, and other rearrangements, are common in human and cancer genomes. Copy number data from array comparative genome hybridization (aCGH) and next-generation DNA sequencing is widely used to measure copy number variants. Comparison of copy number data from multiple individuals reveals recurrent variants. Typically, the interior of a recurrent CNV is examined for genes or other loci associated with a phenotype. However, in some cases, such as gene truncations and fusion genes, the target of variant lies at the boundary of the variant.

Results

We introduce Neighborhood Breakpoint Conservation (NBC), an algorithm for identifying rearrangement breakpoints that are highly conserved at the same locus in multiple individuals. NBC detects recurrent breakpoints at varying levels of resolution, including breakpoints whose location is exactly conserved and breakpoints whose location varies within a gene. NBC also identifies pairs of recurrent breakpoints such as those that result from fusion genes. We apply NBC to aCGH data from 36 primary prostate tumors and identify 12 novel rearrangements, one of which is the well-known TMPRSS2-ERG fusion gene. We also apply NBC to 227 glioblastoma tumors and predict 93 novel rearrangements which we further classify as gene truncations, germline structural variants, and fusion genes. A number of these variants involve the protein phosphatase PTPN12 suggesting that deregulation of PTPN12, via a variety of rearrangements, is common in glioblastoma.

Conclusions

We demonstrate that NBC is useful for detection of recurrent breakpoints resulting from copy number variants or other structural variants, and in particular identifies recurrent breakpoints that result in gene truncations or fusion genes. Software is available at http://http.//cs.brown.edu/people/braphael/software.html.  相似文献   
75.
76.
Sexually transmitted microbes are hypothesized to influence the evolution of reproductive strategies. Though frequently discussed in this context, our understanding of the reproductive microbiome is quite nascent. Indeed, testing this hypothesis first requires establishing a baseline understanding of the temporal dynamics of the reproductive microbiome and of how individual variation in reproductive behavior and age influence the assembly and maintenance of the reproductive microbiome as a whole. Here, we ask how mating activity, breeding stage, and age influence the reproductive microbiome. We use observational and experimental approaches to explain variation in the cloacal microbiome of free‐living, female tree swallows (Tachycineta bicolor). Using microsatellite‐based parentage analyses, we determined the number of sires per brood (a proxy for female mating activity). We experimentally increased female sexual activity by administering exogenous 17ß‐estradiol. Lastly, we used bacterial 16S rRNA amplicon sequencing to characterize the cloacal microbiome. Neither the number of sires per brood nor the increased sexual activity of females significantly influenced female cloacal microbiome richness or community structure. Female age, however, was positively correlated with cloacal microbiome richness and influenced overall community structure. A hypothesis to explain these patterns is that the effect of sexual activity and the number of mates on variation in the cloacal microbiome manifests over an individual''s lifetime. Additionally, we found that cloacal microbiome alpha diversity (Shannon Index, Faith''s phylogenetic distance) decreased and community structure shifted between breeding stages. This is one of few studies to document within‐individual changes and age‐related differences in the cloacal microbiome across successive breeding stages. More broadly, our results contribute to our understanding of the role that host life history and behavior play in shaping the cloacal microbiomes of wild birds.  相似文献   
77.
In an agroindustrial wastewater pond, a naturally occurring unicellular microalga, Chlorella vulgaris, was closely associated with the terrestrial plant-associative N2-fixing bacterium Phyllobacterium myrsinacearum. When the two microorganisms were artificially coimmobilized in alginate beads, they shared the same internal bead cavities, and the production of five microalgal pigments increased, but there were no effects on the number of the cells or the biomass of the microalga. The association, however, reduces the ability of C. vulgaris to remove ammonium ions and phosphorus from water. The bacterium produced nitrate from ammonium in synthetic wastewater with or without the presence of the microalga, and fixed nitrogen in two culture media. Our results suggest that interactions between microalgae and associative bacteria should be considered when cultivating microalgae for wastewater treatment.  相似文献   
78.
79.
The need to replace conventional polymers due to environmental pollution caused by them has led to increased production of biodegradable polymers such as starch. Thus, the application possibilities of starch have increased. In this study, we produced and characterized biodegradable films derived from native and oxidized potato starch. The film-forming solution was prepared with different concentrations of extracted starch (native or oxidized) and a plasticizer (glycerol or sorbitol). Then, the mechanical, barrier, morphological, and structural properties of the films were characterized. The moisture content of the films varied from 15.35?±?1.31 to 21.78?±?0.49%. The elastic modulus of the films ranged from 219?±?14.97 to 2299?±?62.91 MPa. The film of oxidized starch plasticized with sorbitol in the lowest content was the most resistant and flexible; moreover, this film also presented lower water vapor permeability and low solubility in water. Fourier-transform infrared spectroscopic analysis of the biodegradable films indicated the presence of same functional groups as those of starch with bands in the same regions. The film thickness was lower for the films plasticized with glycerol whereas the color variation (Δ?) was lower for the ones plasticized with sorbitol. In case of both plasticizers, the increase in their content decreased the Δ? value. All the biodegradable films presented stability against water absorption owing to their low solubility in water. Morphological evaluation revealed the presence of partially gelatinized starch granules in the films. The roughness parameter (Rq) of the films varied from 3.39 to 10.9 nm, indicating that their surfaces are smooth. X-ray diffraction studies showed a B-type pattern for the starches, which is representative of tubers. Further, the films present higher relative crystallinity (RC) compared to the starches. The biodegradable starch films are uniform, transparent and with low solubility in water. The oxidation of starch and use of sorbitol as a plasticizer resulted in improved properties of the starch films, which is suitable for application.  相似文献   
80.

Background

Cross-sectional and retrospective studies have associated major depressive disorder with glial activation and injury as well as blood–brain barrier disruption, but these associations have not been assessed prospectively. Here, we aimed to determine the relationship between changes in depressive symptom severity and in blood levels of S-100 calcium-binding protein B (S-100B), high-sensitivity C-reactive protein, and interleukin-6 following an inflammatory challenge.

Methods

Fifty unselected participants were recruited from a randomized, controlled trial comparing coronary artery bypass grafting procedures performed with versus without cardiopulmonary bypass for the risk of neurocognitive decline. Depressive symptom severity was measured at baseline, discharge, and six-month follow-up using the Beck Depression Inventory II (BDI-II). The primary outcome of the present biomarker study was acute change in depressive symptom severity, defined as the intra-subject difference between baseline and discharge BDI-II scores. Blood biomarker levels were determined at baseline and 2 days postoperative.

Results

Changes in S-100B levels correlated positively with acute changes in depressive symptom severity (Spearman ρ, 0.62; P = 0.0004) and accounted for about one-fourth of their observed variance (R2, 0.23; P = 0.0105). This association remained statistically significant after adjusting for baseline S-100B levels, age, weight, body-mass index, or β-blocker use, but not baseline BDI-II scores (P = 0.064). There was no statistically significant association between the primary outcome and baseline S-100B levels, baseline high-sensitivity C-reactive protein or interleukin-6 levels, or changes in high-sensitivity C-reactive protein or interleukin-6 levels. Among most participants, levels of all three biomarkers were normal at baseline and markedly elevated at 2 days postoperative.

Conclusions

Acute changes in depressive symptom severity were specifically associated with incremental changes in S-100B blood levels, largely independent of covariates associated with either. These findings support the hypothesis that glial activation and injury and blood–brain barrier disruption can be mechanistically linked to acute exacerbation of depressive symptoms in some individuals.  相似文献   
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