Clostridium difficile isolates from presumed community-associated infections (n = 92) were characterized by toxinotyping, pulsed-field gel electrophoresis, tcdC and cdtB PCR, and antimicrobial ...susceptibility. Nine toxinotypes (TOX) and 31 PFGE patterns were identified. TOX 0 (48, 52%), TOX III (18, 20%), and TOX V (9, 10%) were the most common; three isolates were nontoxigenic.
► MiR-101 inhibits expression of reporter under control of APP 3′-UTR in human cells. ► MiR-101 mediates this effect through one of two predicted target sites. ► MiR-101 reduces expression of ...endogenous APP in human cultured cells. ► APP expression is regulated by endogenous miR-101 in human cells.
The full repertoire of regulatory interactions utilized by human cells to control expression of amyloid-β precursor protein (APP) is still undefined. We investigated here the contribution of microRNA (miRNA) to this regulatory network. Several bioinformatic algorithms predicted miR-101 target sites within the APP 3′-untranslated region (3′-UTR). Using reporter assays, we confirmed that, in human cell cultures, miR-101 significantly reduced the expression of a reporter under control of APP 3′-UTR. Mutation of predicted site 1, but not site 2, eliminated this reporter response. Delivery of miR-101 directly to human HeLa cells significantly reduced APP levels and this effect was eliminated by co-transfection with a miR-101 antisense inhibitor. Delivery of a specific target protector designed to blockade the interaction between miR-101 and its functional target site within APP 3′-UTR enhanced APP levels in HeLa. Therefore, endogenous miR-101 regulates expression of APP in human cells via a specific site located within its 3′-UTR. Finally, we demonstrate that, across a series of human cell lines, highest expression of miR-101 levels was observed in model NT2 neurons.
This study investigated the effect of gametogenesis pattern and sex on levels of paralytic shellfish toxins (PST) accumulated by triploid oysters Crassostrea gigas exposed to a natural bloom of the ...toxic dinoflagellate Alexandrium minutum in the Bay of Brest (Western Brittany, France), over the summer 2014. Toxin accumulation in oysters was proposed to be influenced by the proportion of energy allocated to reproduction versus other metabolisms, as proposed by Haberkorn et al. (2010). Thus, we hypothesized that triploid oysters with different gametogenesis patterns (α or β, producing respectively numerous gametes or rare gametes) could result in differences in toxin accumulation. Toxin level could also be different according to the gender of the oysters. To test these hypotheses, PST levels were measured in the digestive gland of oysters using an ELISA method. Sex, gametogenesis stage and pattern (α or β) of the triploid oysters were determined by histology. Males (24%), females (38%) and hermaphrodites (38%), including synchronous or successive hermaphrodites were represented among the sampled oysters. All of them were at mature stage (III) of gametogenesis. Both α (46%) and β (54%) patterns were represented in the sample set. In these oysters, PST levels appeared independent from sex and gametogenesis pattern. These results suggest that, in triploid oysters, PST accumulation is not influenced by energy allocated to reproduction.
This study appears to be the first to investigate toxin levels depending on gametogenesis pattern in triploid oysters.
This study highlighted that triploid oysters were divided into two classes, α (triploid oysters that maturate with unlocked germ cells and have a consequent number of gametes) and β (triploid oysters that display strongly reduced number of gametes and locked gonial mitosis), with the latter class subdivided into two categories: β1, which presents no germinal cell lineage, and β2, which presents germinal cell lineage.
This study showed that toxin levels in the digestive glands of triploids were not significantly different, neither between gametogenesis patterns nor between sexes. Additionally, despite the different patterns of gametogenesis in the triploid oysters of the present study, no difference in toxin levels accumulated in the digestive glands was detected between α and β oysters, suggesting that reproductive investment in triploid oysters does not influence toxin accumulation.
•Triploid Crassostrea gigas were exposed to a natural bloom of Alexandrium minutum.•Oyster sex does not seem to influence paralytic shellfish toxin levels in triploid oysters.•Gametogenesis pattern does not seem to influence paralytic shellfish toxin levels in triploid oysters.•Fifty percent of sampled triploid oysters showed α pattern, producing numerous mature gametes.
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This work investigates a vacuum induction melted-vacuum arc re-melted (VIM-VAR) and thermo-mechanically processed ternary NiTiCo shape memory alloy. The NiTiCo ingot was hot processed to ...6.35-mm-diameter coiled wire. The coiled wire was subsequently cold drawn to a final wire diameter of 0.53 mm, with interpass anneals. The wires were shape set at 450 °C for 3.5 min. After electropolishing, the wires were subjected to microstructural, thermal, and mechanical characterization studies. Microstructural analysis was performed by transmission electron microscope (TEM), thermal analyses by differential scanning calorimeter (DSC), and bend-free recovery and mechanical testing by uniaxial tensile testing. TEM did not reveal Ni-rich precipitates—either at the grain boundary or in the grain interior. Energy dispersive x-ray spectroscopy showed a uniform distribution of Ni, Ti, and Co in the sample. The DSC results on the shape set wire showed a single-step transformation between the austenite and the R-phase, in the forward and reverse directions. Cyclic tensile tests of the shape set wire, processed under optimum conditions, showed minimum residual strain and a stable upper plateau stress. Further, the fatigue behavior of NiTi and NiTiCo alloys was studied by rotating beam testing. The results showed that the fatigue properties of NiTiCo, under zero mean strain, are equivalent to that of binary NiTi in the high-cycle and medium-cycle regimes, taking into account the higher stiffness of NiTiCo. The above analyses helped in establishing the processing-structure-property correlation in a VIM-VAR-melted NiTiCo shape memory alloy.
Aims
The study aims to demonstrate the antimicrobial and disinfectant resistance phenotypes and genotypes of Escherichia coli isolates obtained from giant pandas (Ailuropoda melanoleuca).
Methods and ...Results
Antimicrobial testing was performed according to the standard disk diffusion method. The minimal inhibitory concentrations (MICs) of disinfectants were determined using the agar dilution method. All isolates were screened for the presence of antimicrobial and disinfectant resistance genes and further analysed for genetic relatedness by pulse‐field gel electrophoresis (PFGE). Results showed that 46·6% of the isolates were resistant to at least one antimicrobial. Escherichia coli isolates showed resistance to fewer antimicrobials as panda age increased. Among antimicrobial‐resistant E. coli isolates, the antimicrobial resistance genes blaCTX‐M (88·2%) and sul1 (92·3%) were most prevalent. The disinfectant resistance genes emrE, ydgE/ydgF, mdfA and sugE(c) were commonly present (68·2–98·9%), whereas qac and sugE(p) were relatively less prevalent (0–21·3%). The frequencies of resistance genes tended to be higher in E. coli isolated in December than in July, and PFGE profiles were also more diverse in isolates in December. The qacEΔ1 and sugE(p) genes were higher in adolescent pandas than in any other age groups. PFGE revealed that antimicrobial resistance correlated well with sampling time and habitat.
Conclusions
This study demonstrated that antimicrobial and disinfectant resistance was common in giant panda‐derived E. coli, and the antimicrobial resistance was associated with sampling time and habitat. Escherichia coli could serve as a critical vector in spreading disinfectant and antimicrobial resistance.
Significance and Impact of the Study
This is the first study that demonstrated the phenotypic and genetic characterizations of antimicrobial and disinfectant resistance in E. coli isolates from more than 60 giant pandas. Frequent transfer of pandas to other cages may lead to the dissemination of antimicrobial resistance. The study highlights the need for regularly monitoring the antimicrobial and disinfectant resistance in bacteria from giant pandas.
DNA microarrays make possible the rapid and comprehensive assessment of the transcriptional activity of a cell, and as such have proven valuable in assessing the molecular contributors to biological ...processes and in the classification of human cancers. The major challenge in using this technology is the analysis of its massive data output, which requires computational means for interpretation and a heightened need for quality data. The optimal analysis requires an accounting and control of the many sources of variance within the system, an understanding of the limitations of the statistical approaches, and the ability to make sense of the results through intelligent database interrogation.
Objective Synthetic glucocorticoid administration to women threatening preterm delivery increases neonatal survival. However, mounting evidence shows that fetal exposure to glucocorticoid levels ...higher than appropriate for current maturation adversely programs offspring development. We examined fetal synthetic glucocorticoid multigenerational metabolic effects on F1 and F2 female offspring. Study Design At 0.7 gestation, pregnant F0 ewes received 4 injections of dexamethasone (2 mg, approximately 60 ug.kg−1 day−1 12 hours apart) or saline (control). F1 female offspring were bred to produce F2 female offspring. Postpubertal pancreatic β-cell function was tested in F1 and F2 by intravenous glucose tolerance test. Results F1 and F2 ewe lambs showed reduced birthweight and morphometrics, and similar increased fasting glucose and decreased intravenous glucose tolerance test β-cell response. Conclusion This is the first demonstration of multigenerational programming of later life β-cell response by clinically relevant doses of synthetic glucocorticoid indicating the need for study of long-term effects of fetal exposure to synthetic glucocorticoid.
Objective Synthetic glucocorticoids (sGCs) are administered to women threatening preterm labor. We have shown multigenerational endocrine and metabolic effects of fetal sGC exposure. We hypothesized ...that sGC exposure would alter the second filial generation (F2) offspring neonatal leptin peak that controls development of appetitive behavior with metabolic consequences. Study Design F0 nulliparous ewes were bred to a single ram. Beginning at day 103 of gestation (term 150 days), dexamethasone (DEX) ewes received 4 injections of 2 mg DEX intramuscularly, 12 hours apart. Control ewes received saline. Ewes lambed naturally. At 22 months of age, F1 offspring were mated to produce F2 offspring. At 10 months of age, F2 female offspring were placed on an ad libitum feeding challenge for 12 weeks. Results DEX F2 female offspring did not show a postnatal leptin peak and their plasma cortisol concentration was elevated in the first days of life. During the feeding challenge, DEX F2 offspring consumed 10% more feed and gained 20% more weight compared with control F2 offspring. At the end of the feeding challenge, DEX F2 offspring had greater adiposity compared with control F2 offspring. F2 sGC offspring showed impaired insulin secretion in response to an intravenous glucose tolerance test. Conclusion sGC administration to F0 mothers eliminates the neonatal leptin peak in F2 female offspring potentially by inhibition caused by elevated cortisol in the DEX F2 offspring. F2 offspring showed increased appetite, weight gain, and adiposity during an ad libitum feeding challenge accompanied by decreased insulin response to an intravenous glucose tolerance test.
The copper mould and molten steel were modelled simultaneously by a three-dimensional (3D) model, which couples fluid flow, heat transfer and solidification. Thermal boundary conditions (e.g. air gap ...distribution, slag resistance, contact resistance) along casting direction and circumference direction were discussed and applied. The results of solid shell thickness distribution were compared with reference experimental data and reasonable agreements were found. The calculations indicate that, the shell thickness distribution along circumference in web was affected by the cross-section sizes. The uniform shell thickness distributions at narrow face and R corner were caused by the scouring of fluid flow. The heat transfer fluxes at hot face of mould were various at different locations.
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