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51.
Bacterial Synergism or Antagonism in a Gel Cassette System   总被引:3,自引:2,他引:1       下载免费PDF全文
The growth and the metabolic activity of Shewanella putrfaciens, Brochothrix thermosphacta, and Pseudomonas sp., when cultured individually or in all possible combinations in gel cassettes system supplemented with 0.1% glucose at 5°C, were investigated. The overall outcome was that the coexistence of the above-mentioned microorganisms affected not only each growth rate but also their type of metabolic end products compared to the control cultures. These effects were varied and depended on the selection of the combination of the tested bacteria. For example, the growth of Pseudomonas sp. strains cocultured with either B. thermosphacta or S. putrefaciens strains resulted in different effects: a promoting one for the first and an inhibitory one for the second. Moreover, the production of formic acid and two unidentified organic acids (peaks a and b) was characteristic in all cases in which S. putrefaciens was cultured.  相似文献   
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53.
The use of pluripotent stem cells in regenerative medicine and disease modeling is complicated by the variation in differentiation properties between lines. In this study, we characterized 13 human embryonic stem cell (hESC) and 26 human induced pluripotent stem cell (hiPSC) lines to identify markers that predict neural differentiation behavior. At a general level, markers previously known to distinguish mouse ESCs from epiblast stem cells (EPI-SCs) correlated with neural differentiation behavior. More specifically, quantitative analysis of miR-371-3 expression prospectively identified hESC and hiPSC lines with differential neurogenic differentiation propensity and in vivo dopamine neuron engraftment potential. Transient KLF4 transduction increased miR-371-3 expression and altered neurogenic behavior and pluripotency marker expression. Conversely, suppression of miR-371-3 expression in KLF4-transduced cells rescued neural differentiation propensity. miR-371-3 expression level therefore appears to have both a predictive and a functional role in determining human pluripotent stem cell neurogenic differentiation behavior.  相似文献   
54.

Background

Pirfenidone is an antifibrotic compound approved for the treatment of idiopathic pulmonary fibrosis (IPF). We present our real-world experience in terms of Pirfenidone’s effect on mortality and adverse events profile outside the restrictions of a clinical trial.

Methods

This is a retrospective observational intention to treat study of 82 consecutive IPF patients (UHH cohort).

Results

We observed a high 3-years survival rate of 73% without excluding patients who discontinued treatment for different reasons. The survival was compared to the survival of an IPF cohort from a tertiary referral center (RBH cohort). After exclusion of severe cases (DLco<?30%), in unadjusted analysis, the survival in the UHH cohort was better than in the RBH cohort (HR:0.32, 95% CI: 0.19–0.53, p?<?0.0001). After adjustment for age, gender and FVC, the survival remained higher in the UHH cohort (HR:0.28, 95% CI: 0.16–0.48, p?<?0.0001). We observed a similar safety profile compared to previously published data and a lower rate of drug discontinuation due to photosensitivity reactions. Conclusion: Pirfenidone provides a survival benefit in a real-life IPF cohort compared to previously used medications. Counselling patients and proactively managing possible adverse effects can reduce the necessity to discontinue pirfenidone.
  相似文献   
55.
We report the current best estimate of the effects of cognitive behavior therapy (CBT) in the treatment of major depression (MDD), generalized anxiety disorder (GAD), panic disorder (PAD) and social anxiety disorder (SAD), taking into account publication bias, the quality of trials, and the influence of waiting list control groups on the outcomes. In our meta‐analyses, we included randomized trials comparing CBT with a control condition (waiting list, care‐as‐usual or pill placebo) in the acute treatment of MDD, GAD, PAD or SAD, diagnosed on the basis of a structured interview. We found that the overall effects in the 144 included trials (184 comparisons) for all four disorders were large, ranging from g=0.75 for MDD to g=0.80 for GAD, g=0.81 for PAD, and g=0.88 for SAD. Publication bias mostly affected the outcomes of CBT in GAD (adjusted g=0.59) and MDD (adjusted g=0.65), but not those in PAD and SAD. Only 17.4% of the included trials were considered to be high‐quality, and this mostly affected the outcomes for PAD (g=0.61) and SAD (g=0.76). More than 80% of trials in anxiety disorders used waiting list control groups, and the few studies using other control groups pointed at much smaller effect sizes for CBT. We conclude that CBT is probably effective in the treatment of MDD, GAD, PAD and SAD; that the effects are large when the control condition is waiting list, but small to moderate when it is care‐as‐usual or pill placebo; and that, because of the small number of high‐quality trials, these effects are still uncertain and should be considered with caution.  相似文献   
56.
BackgroundHuntington’s disease is an inherited neurodegenerative disorder characterised by motor, cognitive and psychiatric disturbances. Patients exhibit other symptoms including sleep and mood disturbances, muscle atrophy and weight loss which may be linked to hypothalamic pathology and dysfunction of hypothalamo-pituitary axes.MethodsWe studied neuroendocrine profiles of corticotropic, somatotropic and gonadotropic hypothalamo-pituitary axes hormones over a 24-hour period in controlled environment in 15 healthy controls, 14 premanifest and 13 stage II/III Huntington’s disease subjects. We also quantified fasting levels of vasopressin, oestradiol, testosterone, dehydroepiandrosterone sulphate, thyroid stimulating hormone, free triiodothyronine, free total thyroxine, prolactin, adrenaline and noradrenaline. Somatotropic axis hormones, growth hormone releasing hormone, insulin-like growth factor-1 and insulin-like factor binding protein-3 were quantified at 06:00 (fasting), 15:00 and 23:00. A battery of clinical tests, including neurological rating and function scales were performed.Results24-hour concentrations of adrenocorticotropic hormone, cortisol, luteinizing hormone and follicle-stimulating hormone did not differ significantly between the Huntington’s disease group and controls. Daytime growth hormone secretion was similar in control and Huntington’s disease subjects. Stage II/III Huntington’s disease subjects had lower concentration of post-sleep growth hormone pulse and higher insulin-like growth factor-1:growth hormone ratio which did not reach significance. In Huntington’s disease subjects, baseline levels of hypothalamo-pituitary axis hormones measured did not significantly differ from those of healthy controls.ConclusionsThe relatively small subject group means that the study may not detect subtle perturbations in hormone concentrations. A targeted study of the somatotropic axis in larger cohorts may be warranted. However, the lack of significant results despite many variables being tested does imply that the majority of them do not differ substantially between HD and controls.  相似文献   
57.
Thymidine phosphorylase (TP) first identified as platelet derived endothelial cell growth factor (PD-ECGF) plays a key role in nucleoside metabolism. Human TP (hTP) is implicated in angiogenesis and is overexpressed in several solid tumors. Here, we report the crystal structures of recombinant hTP and its complex with a substrate 5-iodouracil (5IUR) at 3.0 and 2.5 Å, respectively. In addition, we provide information on the role of specific residues in the enzymatic activity of hTP through mutagenesis and kinetic studies.  相似文献   
58.
In sheep, scrapie susceptibility is so strongly associated with single nucleotide polymorphisms (SNPs) in the gene encoding the prion protein (PrP) that this linkage constitutes the basis for selective breeding strategies directed toward controlling the disease. For goats, in contrast, the association between scrapie susceptibility/resistance and variations in the PrP gene is far weaker, with only a few identified SNPs showing an influence on scrapie susceptibility. A recent survey of PrP genotypes in Cypriot goats, however, revealed the existence of a robust association between polymorphisms at codon 146 of the caprine PrP gene and resistance/susceptibility to natural scrapie. Here we describe here a high-throughput assay, based on homogeneous MassExtend technology coupled with mass spectrometry, for genotyping codon 146 of the caprine PrP gene. Our results demonstrate that this assay exhibits high accuracy, reproducibility, and repeatability, thereby making it suitable for large-scale SNP genotyping, as required for scrapie surveillance programs.  相似文献   
59.
Abnormal apoptotic events in chronic obstructive pulmonary disease (COPD) subvert cellular homeostasis and may play a primary role in its pathogenesis. However, studies in human subjects are limited.p53 and bcl2 protein expression was measured by western blot on lung tissue specimens from 43 subjects (23 COPD smokers and 20 non-COPD smokers), using beta-actin as internal control. Additionally, p53 and bcl2 expression patterns were evaluated by immunohistochemistry in formalin-fixed, paraffin-embedded lung tissue sections from the same individuals.Western blot analysis showed statistically significant increased p53 protein levels in COPD smokers in comparison with non-COPD smokers (p = 0.038), while bcl2 protein levels were not statistically different between the two groups. Lung immunohistochemistry showed increased ratio of positive p53-stained type II pneumocytes/total type II pneumocytes in COPD smokers compared to non-COPD smokers (p = 0.01), whereas the p53 staining ratio in alveolar macrophages and in lymphocyte-like cells did not differ statistically between the two groups. On the other hand, bcl2 expression did not differ between the two groups in all three cell types.The increased expression of pro-apoptotic p53 in type II pneumocytes of COPD patients not counterbalanced by the anti-apoptotic bcl2 could reflect increased apoptosis in the alveolar epithelium of COPD patients. Our results confirm previous experiments and support the hypothesis of a disturbance in the balance between the pro- and anti-apoptotic mediators in COPD.  相似文献   
60.
The aim of this paper was to evaluate the use of different bulking agents in different ratios as a means to control, optimise and eventually reduce the duration of the thermophilic period in two-phase olive oil mill sludge (OOMS) composting. The bulking agents used were: (i) olive tree leaves (OTL), (ii) olive tree shredded branches (OTB) and (iii) woodchips (WDC). The selection of these materials was based on their abundance and availability on the island of Crete, the southernmost point of Greece. The ratios studied were: Pile 1, OOMS:OTL in 1:1 v/v; Pile 2, OOMS:WDC in 1:1.5 v/v; Pile 3, OOMS:OTL in 1:2 v/v; Pile 4, OOMS:OTL:OTB in 1:1:1 v/v; and Pile 5, OOMS:OTL:OTB in 1:1:2 v/v. The composting system used was that of windrows with the volume of each pile approximately 20–25 m3. The experiments took place over two consecutive years. A composting turner was used and turnings were performed at one and two week intervals. In each pile a variety of physiochemical parameters were monitored. Temperature remained high in all five trials. Piles 1, 2, 3, 4 and 5 temperatures recorded values of above 50 °C for 106, 158, 160, 175 and 183 days, respectively. Volumes were reduced by approximately 67%, 62%, 63%, 80% and 84%, respectively. Temperature remained high, mainly due to the presence in large amounts of oily substances which during their complete oxidation release important amounts of energy and aid the cometabolism of more stable molecules such as lignin. This process is better described as the slow “burning” of a “fuel” mixture in an “engine” than composting. This approach is based on the extensive similarities of this process to that of crude oil sludge or similar waste composting.  相似文献   
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