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31.
Mu-En Liu Shih-Jen Tsai Wei-Chiao Chang Chun-Hung Hsu Ti Lu Kuo-Sheng Hung Wen-Ta Chiu Wei-Pin Chang 《PloS one》2013,8(4)
Background
This study estimates the risk of stroke within 5 years of newly diagnosed dementia among elderly persons aged 65 and above. We examined the relationship between antipsychotic usage and development of stroke in patients with dementia.Methods
We conducted a nationwide 5-year population-based study using data retrieved from the Longitudinal Health Insurance Database 2005 (LHID2005) in Taiwan. The study cohort comprised 2243 patients with dementia aged ≥65 years who had at least one inpatient service claim or at least 2 ambulatory care claims, whereas the comparison cohort consisted of 6714 randomly selected subjects (3 for every dementia patient) and were matched with the study group according to sex, age, and index year. We further classified dementia patients into 2 groups based on their history of antipsychotic usage. A total of 1450 patients were classified into the antipsychotic usage group and the remaining 793 patients were classified into the non-antipsychotic usage group. Cox proportional-hazards regressions were performed to compute the 5-year stroke-free survival rates after adjusting for potentially confounding factors.Results
The dementia patients have a 2-fold greater risk of developing stroke within 5 years of diagnosis compared to non-dementia age- and sex-matched subjects, after adjusting for other risk factors (95% confidence interval (CI) = 2.58–3.08; P<.001). Antipsychotic usage among patients with dementia increases risk of stroke 1.17-fold compared to patients without antipsychotic treatment (95% CI = 1.01–1.40; P<.05).Conclusions
Dementia may be an independent risk factor for stroke, and the use of antipsychotics may further increase the risk of stroke in dementia patients. 相似文献32.
Alex Gutteridge J. Michael Rukstalis Daniel Ziemek Mark Tié Lin Ji Rebeca Ramos-Zayas Nancy A. Nardone Lisa D. Norquay Martin B. Brenner Kim Tang John D. McNeish Rebecca K. Rowntree 《PloS one》2013,8(2)
We have used a previously unavailable model of pancreatic development, derived in vitro from human embryonic stem cells, to capture a time-course of gene, miRNA and histone modification levels in pancreatic endocrine cells. We investigated whether it is possible to better understand, and hence control, the biological pathways leading to pancreatic endocrine formation by analysing this information and combining it with the available scientific literature to generate models using a casual reasoning approach. We show that the embryonic stem cell differentiation protocol is highly reproducible in producing endocrine precursor cells and generates cells that recapitulate many aspects of human embryonic pancreas development, including maturation into functional endocrine cells when transplanted into recipient animals. The availability of whole genome gene and miRNA expression data from the early stages of human pancreatic development will be of great benefit to those in the fields of developmental biology and diabetes research. Our causal reasoning algorithm suggested the involvement of novel gene networks, such as NEUROG3/E2F1/KDM5B and SOCS3/STAT3/IL-6, in endocrine cell development We experimentally investigated the role of the top-ranked prediction by showing that addition of exogenous IL-6 could affect the expression of the endocrine progenitor genes NEUROG3 and NKX2.2. 相似文献
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【背景】大熊猫的肠道内微生物类群丰富,种群结构与宿主的年龄、生存环境、季节变化等因素有关,其中年龄是影响肠道菌群组成的重要因素之一。【目的】以不同年龄阶段的大熊猫粪便为研究对象,旨在了解不同年龄大熊猫肠道内芽孢杆菌的多样性,探究大熊猫肠道芽孢杆菌种类与年龄段之间的关系,并为优良益生菌剂的开发提供菌种资源。【方法】用稀释涂布法分离大熊猫粪便中的芽孢杆菌,对分离的菌株进行BOXA1R-PCR、16S rRNA基因系统发育及主成分分析,揭示大熊猫肠道中可培养芽孢杆菌的多样性;采用对峙生长法和药敏纸片琼脂扩散法分别检测菌株的抗菌能力和药敏性。【结果】从大熊猫粪便中共分离出90株芽孢杆菌,基于BOXA1R-PCR分析菌株的遗传多样性并从中选取41株代表菌株,经16Sr RNA基因测序分析后,结果显示归属于枯草芽孢杆菌(Bacillus subtilis)、萎缩芽孢杆菌(Bacillus atrophaeus)、贝莱斯芽孢杆菌(Bacillus velezensis)、甲基营养型芽孢杆菌(Bacillusmethylotrophicus)、解淀粉芽孢杆菌(Bacillusamyloliquefaciens)和短小芽孢杆菌(Bacillus pumilus)6个种;主成分分析结果表明大熊猫肠道芽孢杆菌种群组成与年龄存在一定的相关性。所有的供试菌株都具有纤维素降解潜力,大部分菌株对病原菌具有不同程度的抑制作用;除对青霉素具有耐药性外,供试菌株对常见的抗生素耐受性低。【结论】年龄是影响大熊猫肠道芽孢杆菌分布的重要因素,成年大熊猫肠道芽孢杆菌种类多样性最丰富,这为大熊猫益生菌制剂的开发提供了菌种资源。 相似文献
37.
RNase MRP cleaves the CLB2 mRNA to promote cell cycle progression: novel method of mRNA degradation 下载免费PDF全文
RNase mitochondrial RNA processing (RNase MRP) mutants have been shown to have an exit-from-mitosis defect that is caused by an increase in CLB2 mRNA levels, leading to increased Clb2p (B-cyclin) levels and a resulting late anaphase delay. Here we describe the molecular defect behind this delay. CLB2 mRNA normally disappears rapidly as cells complete mitosis, but the level remains high in RNase MRP mutants. This is in direct contrast to other exit-from-mitosis mutants and is the result of an increase in CLB2 mRNA stability. We found that highly purified RNase MRP cleaved the 5' untranslated region (UTR) of the CLB2 mRNA in several places in an in vitro assay. In vivo, we identified RNase MRP-dependent cleavage products on the CLB2 mRNA that closely matched in vitro products. Disposal of these products was dependent on the 5'-->3' exoribonuclease Xrn1 and not the exosome. Our results demonstrate that the endoribonuclease RNase MRP specifically cleaves the CLB2 mRNA in its 5'-UTR to allow rapid 5' to 3' degradation by the Xrn1 nuclease. Degradation of the CLB2 mRNA by the RNase MRP endonuclease provides a novel way to regulate the cell cycle that complements the protein degradation machinery. In addition, these results denote a new mechanism of mRNA degradation not seen before in the yeast Saccharomyces cerevisiae. 相似文献
38.
Ling TC Loong CK Tan WS Tey BT Abdullah WM Ariff A 《Journal of microbiology (Seoul, Korea)》2004,42(3):228-232
In this paper, we investigated the development of a simplified and rapid primary capture step for the recovery of M13 bacteriophage from particulate-containing feedstock. M13 bacteriophage, carrying an insert, was propagated and subsequently purified by the application of both conventional multiple steps and expanded bed anion exchange chromatography. In the conventional method, precipitation was conducted with PEG/NaCl, and centrifugation was also performed. In the single step expanded bed anion exchange adsorption, UpFront FastLine 20 (20 mm i.d.) from UpFront Chromatography was used as the contactor, while 54 ml (Ho = 15 cm) of STREAMLINE DEAE (rho = 1.2 g/cm3) from Amersham Pharmacia Biotechnology was used as the anion exchanger. The performance of the two methods were evaluated, analysed, and compared. It was demonstrated that the purification of the M13 bacteriophage, using expanded bed anion exchange adsorption, yielded the higher recovery percentage, at 82.86%. The conventional multiple step method yielded the lower recovery percentage, 36.07%. The generic application of this integrated technique has also been assessed. 相似文献
39.
Beng?Ti?TeyEmail author Kok?Hoe?Yong Hong?Puay?Ong Tau?Chuan?Ling Swee?Tin?Ong Yan?Peng?Tan Arbakariya?Ariff Wen?Siang?Tan 《Biotechnology and Bioprocess Engineering》2004,9(5):374-378
The effects of various environmental factors such as pH (5, 6, 7, 8 and 9), temperature (30, 37 and 40°C) and rotational speed
(150, 200 and 250 rpm) on the growth and the hepatitis B core antigen (HBcAg) production ofEscherichia coli W3110IQ were examined in the present study. The highest growth rate is achieved at PH 7, 37°C and at a rotational speed of
250 rpm which is 0.927 h−1. The effect of pH on cell growth is more substantial compared to other parameters; it recorded a 123% different between the
highest growth rate (0.927 h−1) at pH 7 and lowest growth at pH 5. The highest protein yield is achieved at pH 9, rotational speed of 250 rpm and 40°C.
The yield of protein at pH 7 is 154% higher compared to the lowest yield achieved at pH 5. There is about 28% different of
the protein yield for theE. coli cultivated at 250 rpm compared to that at 150 rpm which has the lowest HBcAg yield. The yield of protein at 40°C is 38% higher
compared to the lowest yield achieved, at 30°C. 相似文献
40.
Erdodi F Kiss E Walsh MP Stefansson B Deng JT Eto M Brautigan DL Hartshorne DJ 《Biochemical and biophysical research communications》2003,306(2):382-387
Protein phosphatases play key roles in cellular regulation and are subjected to control by protein inhibitors whose activity is in turn regulated by phosphorylation. Here we investigated the possible regulation of phosphorylation-dependent type-1 protein phosphatase (PP1) inhibitors, CPI-17, PHI-1, and KEPI, by various kinases. Protein kinases A (PKA) and G (PKG) phosphorylated CPI-17 at the inhibitory site (T38), but not PHI-1 (T57). Phosphorylated CPI-17 inhibited the activity of both the PP1 catalytic subunit (PP1c) and the myosin phosphatase holoenzyme (MPH) with IC(50) values of 1-8 nM. PKA predominantly phosphorylated a site distinct from the inhibitory T73 in KEPI, whereas PKG was ineffective. Integrin-linked kinase phosphorylated KEPI (T73) and this dramatically increased inhibition of PP1c (IC(50)=0.1 nM) and MPH (IC(50)=8 nM). These results suggest that the regulatory phosphorylation of CPI-17 and KEPI may involve distinct kinases and signaling pathways. 相似文献