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1.
K R Shanmugasundaram K Dhandapani A Visvanathan 《Journal of biochemical and biophysical methods》1985,11(4-5):227-233
The use of ferric acetate-uranium acetate colour reaction for the estimation of cholesterol in the supernatants of plasma samples after precipitation of low density lipoprotein (LDL) and very low density lipoprotein (VLDL) cholesterol by heparin-MnCl2 was assessed and compared with the conventional method using the FeCl3 colour reaction and also with the method using o-phthalaldehyde as the colouring reagent. All three methods gave comparable values when total cholesterol in plasma samples was determined and also when high density lipoprotein (HDL) fractions were separated by ultracentrifugation and the cholesterol contents determined. But when heparin-MnCl2 precipitation was used for HDL separation, and the cholesterol content determined, the FeCl3 method gave significantly lower values. This could be due to interference of the cholesterol colour reaction with FeCl3, due to Mn2+ ions present in the supernatant. Addition of Mn2+ to cholesterol standards and subsequent colour development with ferric acetate-uranium acetate and FeCl3 reagents showed that Mn2+ decreased the absorbancy of the coloured complex at 560 nm only when FeCl3 was used. Percentage recovery of added cholesterol was also lower when the heparin-MnCl2 supernatant was treated with FeCl3 reagent for colour development. Use of ferric acetate-uranium acetate reagent provides a simpler and quicker method. It does not suffer from interference due to the presence of Mn2+ ions and gives results comparable to the o-phthalaldehyde method and those using ultracentrifugation as the separation procedure. 相似文献
2.
A thermophilic Bacillus stearothermophilus strain AP-4 excreting a thermostable alkaline protease, was isolated from a local compost. Maximum activity of protease (250 U/ml) was after 36 h growth in broth at pH 9.0 and at 55°C. The protease was optimally active at pH 9.0 and 55°C and was stable in 5 mm CaCl2. The enzyme was completely inactivated by PMSF, EDTA and -mercaptoethanol. It is therefore a metal ion-dependent, alkaline, serine protease.R. Dhandapani and R. Vijayaragavan are with the Centre for Plant Molecular Biology & Biotechnology, Tamil Nadu Agricultural University, Coimbatore 641 003, India 相似文献
3.
Kurinchi S. Gurusamy Edward Wilson Ronald L. Koretz Victoria B. Allen Brian R. Davidson Andrew K. Burroughs Christian Gluud 《PloS one》2013,8(12)
Background
Randomised clinical trials (RCTs) of antiviral interventions in patients with chronic hepatitis C virus (HCV) infection use sustained virological response (SVR) as the main outcome. There is sparse information on long-term mortality from RCTs.Methods
We created a decision tree model based on a Cochrane systematic review on interferon retreatment for patients who did not respond to initial therapy or who relapsed following SVR. Extrapolating data to 20 years, we modelled the outcome from three scenarios: (1) observed medium-term (5 year) annual mortality rates continue to the long term (20 years); (2) long-term annual mortality in retreatment responders falls to that of the general population while retreatment non-responders continue at the medium-term mortality; (3) long-term annual mortality in retreatment non-responders is the same as control group non-responders (i.e., the increased treatment-related medium mortality “wears off”).Results
The mean differences in life expectancy over 20 years with interferon versus control in the first, second, and third scenarios were -0.34 years (95% confidence interval (CI) -0.71 to 0.03), -0.23 years (95% CI -0.69 to 0.24), and -0.01 (95% CI -0.3 to 0.27), respectively. The life expectancy was always lower in the interferon group than in the control group in scenario 1. In scenario 3, the interferon group had a longer life expectancy than the control group only when more than 7% in the interferon group achieved SVR.Conclusions
SVR may be a good prognostic marker but does not seem to be a valid surrogate marker for assessing HCV treatment efficacy of interferon retreatment. The SVR threshold at which retreatment increases life expectancy may be different for different drugs depending upon the adverse event profile and treatment efficacy. This has to be determined for each drug by RCTs and appropriate modelling before SVR can be accepted as a surrogate marker. 相似文献4.
Annan Sudarsan Arun Kumar Gurusamy Umamaheswaran Ramamoorthy Padmapriya Jayaraman Balachandar Chandrasekaran Adithan 《Molecular biology reports》2013,40(2):1275-1281
Myocardial infarction (MI) is a complex multi-factorial, polygenic disorder which results from an interaction between a person’s genetic makeup and various environmental factors. Nitric oxide (NO), a potent vasodilator produced by endothelial cells, plays an important role in the regulation of blood pressure, regional blood flow and also inhibits platelet aggregation, vascular smooth muscle cell proliferation and leukocyte adhesion to vascular endothelium. Our aim was to analyze the association of NOS3 (endothelial nitric oxide synthase 3) 894G>T and ?786T>C gene polymorphisms and MI risk in the South Indian population. A total of 287 MI patients, 279 risk control patients and 321 healthy controls were recruited for the retrospective study. Genotyping was done using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). There was no significant association observed between NOS3 894G>T, ?786T>C polymorphisms and MI. A significant difference was observed in the distribution of GT genotype of the NOS3 894G>T polymorphism between the cases and the risk controls (p = 0.05) but the odds ratio (0.6) did not show risk for MI. The present study showed lack of association between NOS3 gene polymorphisms and MI in South Indian population. 相似文献
5.
6.
Kurinchi S. Gurusamy Jessica Vaughan Ian S. Fraser Lawrence M. J. Best Toby Richards 《PloS one》2016,11(2)
Background
Uterine fibroids are common, often symptomatic and a third of women need repeated time off work. Consequently 25% to 50% of women with fibroids receive surgical treatment, namely myomectomy or hysterectomy. Hysterectomy is the definitive treatment as fibroids are hormone dependent and frequently recurrent. Medical treatment aims to control symptoms in order to replace or delay surgery. This may improve the outcome of surgery and prevent recurrence.Purpose
To determine whether any medical treatment can be recommended in the treatment of women with fibroids about to undergo surgery and in those for whom surgery is not planned based on currently available evidence.Study Selection
Two authors independently identified randomised controlled trials (RCT) of all pharmacological treatments aimed at the treatment of fibroids from a list of references obtained by formal search of MEDLINE, EMBASE, Cochrane library, Science Citation Index, and ClinicalTrials.gov until December 2013.Data Extraction
Two authors independently extracted data from identified studies.Data Synthesis
A Bayesian network meta-analysis was performed following the National Institute for Health and Care Excellence—Decision Support Unit guidelines. Odds ratios, rate ratios, or mean differences with 95% credible intervals (CrI) were calculated.Results and Limitations
A total of 75 RCT met the inclusion criteria, 47 of which were included in the network meta-analysis. The overall quality of evidence was very low. The network meta-analysis showed differing results for different outcomes.Conclusions
There is currently insufficient evidence to recommend any medical treatment in the management of fibroids. Certain treatments have future promise however further, well designed RCTs are needed. 相似文献7.
8.
Transforming growth factor-β (TGF-β) has diverse and multiple roles throughout the body. This review focuses on the evidence
supporting its functions in the central nervous system, with a particular emphasis on its purported role in cerebral ischemia.
Numerous studies have documented that TGF-β1 levels are enhanced in the brain following cerebral ischemia. As evidence that
such an upregulation is beneficial, agonist studies have demonstrated that TGF-β1 reduces neuronal cell death and infarct
size following middle cerebral artery occlusion (MCAO), while conversely, antagonist studies have shown increased neuronal
cell death and infarct size after MCAO. These studies suggest that TGF-β1 has a neuroprotective role in cerebral ischemia.
Recent work with adenoviral-mediated overexpression of TGF-β1 in vivo in mice has further implicated a neuroprotective role
for TGF-β1 in cerebral ischemia, as evidenced by a reduction in neuronal cell death, infarct size, and neurological outcome.
Additionally, numerous in vitro studies have documented the neuroprotective ability of TGF-β1 in neurons from a variety of
species, including rats, mice, chicks, and humans. Of significant interest, TGF-β1 was shown to be protective against a wide
variety of death-inducing agents/insults, including hypoxia/ischemia, glutamate excitotoxicity, β-amyloid, oxidative damage,
and human immunodeficiency virus. The mechanism of TGF-β1-mediated neuroprotection remains to be resolved, but early evidence
suggests that TGF-β1 regulates the expression and ratio of apoptotic (Bad) and antiapoptotic proteins (Bcl-2, Bcl-x1), creating an environment favorable for cell survival of death-inducing insults. Taken as a whole, these results suggest
that TGF-β1 is an important neuroprotective factor that can reduce damage from a wide-array of death-inducing agents/insults
in vitro, as well as exert protection of the brain during cerebral ischemia.
The authors’ research is supported by research grants (HD-28964 and AG-17186 to DWB) from the National Institutes of Health,
NICHD, and NIA. 相似文献
9.
Seasonal changes in the fatty acid composition of phospholipids (PL), monoglycerides (MG), diglycerides (DG), free fatty acids (FA) and triglycerides (TG) separated from oleosomes (lipid bodies) of perennial root nodules of beach pea (Lathyrus maritimus) were analysed. Thin layer chromatography (TLC) revealed that PL and MG are the major lipids in nodule oleosomes. The fatty acid profile and overall double bond index (DBI) varied among lipid classes depending upon the season. High DBI in PL and MG found during late winter and early spring indicated that they may play a major role in winter survival and regeneration of perennial nodules. The DBI of DG was high at the end of the fall season and the DBI of FA and TG was high in summer months. The dominant fatty acids are C16:0 followed by C18:0 and C18:1. The levels of many unsaturated fatty acids such as C18:1, C18:2 and C18:3 increased while saturated fatty acid C18:0 decreased during winter. These unsaturated fatty acids possibly play an important role in the protection of nodule cells from cold stress. Nodules seem to retain some fatty acids and selectively utilize specific fatty acids to survive the winter and regenerate in spring. 相似文献
10.
Detailed structural analysis of protein necessitates investigation at primary, secondary and tertiary levels, respectively. Insight into protein secondary structures pave way for understanding the type of secondary structural elements involved (α-helices, β-strands etc.), the amino acid sequence that encode the secondary structural elements, number of residues, length and, percentage composition of the respective elements in the protein. Here we present a standalone tool entitled "ExSer" which facilitate an automated extraction of the amino acid sequence that encode for the secondary structural regions of a protein from the protein data bank (PDB) file. AVAILABILITY: ExSer is freely downloadable from http://code.google.com/p/tool-exser/ 相似文献