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1.
High-affinity L-arabinose transport operon. Nucleotide sequence and analysis of gene products 总被引:20,自引:0,他引:20
J B Scripture C Voelker S Miller R T O'Donnell L Polgar J Rade B F Horazdovsky R W Hogg 《Journal of molecular biology》1987,197(1):37-46
The nucleotide sequence of the "high-affinity" L-arabinose transport operon has been determined 3' from the regulatory region and found to contain three open reading frames designated araF, araG and araH. The first gene 3' to the regulatory region, araF, encodes the 23-residue signal peptide and the 306-residue mature form of the L-arabinose binding protein (33,200 Mr). The binding protein, which has been described elsewhere, is hydrophilic, soluble and found in the periplasm of Escherichia coli. This gene is followed by an intragenic space of 72 nucleotides, which contains a region of dyad symmetry 23 nucleotides long capable of forming an 11-member stem-loop. The second gene, designated araG, contains an open reading frame capable of encoding an equally hydrophilic protein containing 504 residues (55,000 Mr). Following a 14-nucleotide spacer, which does not appear to have any secondary structure, the third open reading frame, herein designated araH, is capable of encoding a hydrophobic protein containing 329 residues (34,000 Mr) that can only be envisioned as having an integral membrane location. 3' to araH there is a T-rich region containing a 24-nucleotide area of dyad symmetry centered 55 nucleotides from the termination codon. Analysis of the derived primary sequences of the araG and araH products indicates the nature and potential features of these components. The araG protein was found to possess internal homology between its amino and carboxyl-terminal halves, suggesting a common origin. The araG gene product has been shown to be homologous to the rbsA gene product, the hisP product, the ptsB product and the malK product, all of which presumably play similar roles in their respective transport systems. Putative ATP binding sites are observed within the regions of homology. The araH gene product has been shown to be homologous to the rbsC gene product, which is the first observed homology between two purported membrane proteins. 相似文献
2.
Ivan Soldatovic Rade Vukovic Djordje Culafic Milan Gajic Vesna Dimitrijevic-Sreckovic 《PloS one》2016,11(1)
Objective
To evaluate siMS score and siMS risk score, novel continuous metabolic syndrome scores as methods for quantification of metabolic status and risk.Materials and Methods
Developed siMS score was calculated using formula: siMS score = 2*Waist/Height + Gly/5.6 + Tg/1.7 + TAsystolic/130—HDL/1.02 or 1.28 (for male or female subjects, respectively). siMS risk score was calculated using formula: siMS risk score = siMS score * age/45 or 50 (for male or female subjects, respectively) * family history of cardio/cerebro-vascular events (event = 1.2, no event = 1). A sample of 528 obese and non-obese participants was used to validate siMS score and siMS risk score. Scores calculated as sum of z-scores (each component of metabolic syndrome regressed with age and gender) and sum of scores derived from principal component analysis (PCA) were used for evaluation of siMS score. Variants were made by replacing glucose with HOMA in calculations. Framingham score was used for evaluation of siMS risk score.Results
Correlation between siMS score with sum of z-scores and weighted sum of factors of PCA was high (r = 0.866 and r = 0.822, respectively). Correlation between siMS risk score and log transformed Framingham score was medium to high for age groups 18+,30+ and 35+ (0.835, 0.707 and 0.667, respectively).Conclusions
siMS score and siMS risk score showed high correlation with more complex scores. Demonstrated accuracy together with superior simplicity and the ability to evaluate and follow-up individual patients makes siMS and siMS risk scores very convenient for use in clinical practice and research as well. 相似文献3.
Paresh Vamanrao Dave Amar Niranjan Shah Pankaj B. Nimavat Bhavesh B. Modi Kirit R. Pujara Pradip Patel Keshabhai Mehariya Kiran Vaman Rade Soma Shekar Kuldeep S. Sachdeva John E. Oeltmann Ajay M. V. Kumar 《PloS one》2016,11(2)
Background
The World Health Organization recommends direct observation of treatment (DOT) to support patients with tuberculosis (TB) and to ensure treatment completion. As per national programme guidelines in India, a DOT provider can be anyone who is acceptable and accessible to the patient and accountable to the health system, except a family member. This poses challenges among children with TB who may be more comfortable receiving medicines from their parents or family members than from unfamiliar DOT providers. We conducted a non-inferiority trial to assess the effect of family DOT on treatment success rates among children with newly diagnosed TB registered for treatment during June–September 2012.Methods
We randomly assigned all districts (n = 30) in Gujarat to the intervention (n = 15) or usual-practice group (n = 15). Adult family members in the intervention districts were given the choice to become their child’s DOT provider. DOT was provided by a non-family member in the usual-practice districts. Using routinely collected clinic-based TB treatment cards, we compared treatment success rates (cured and treatment completed) between the two groups and the non-inferiority limit was kept at 5%.Results
Of 624 children with newly diagnosed TB, 359 (58%) were from intervention districts and 265 (42%) were from usual-practice districts. The two groups were similar with respect to baseline characteristics including age, sex, type of TB, and initial body weight. The treatment success rates were 344 (95.8%) and 247 (93.2%) (p = 0.11) among the intervention and usual-practice groups respectively.Conclusion
DOT provided by a family member is not inferior to DOT provided by a non-family member among new TB cases in children and can attain international targets for treatment success.Trial Registration
Clinical Trials Registry–India, National Institute of Medical Statistics (Indian Council of Medical Research) CTRI/2015/09/006229 相似文献4.
Babić Z Bogdanović Z Dorosulić Z Basha M Krznarić Z Sjekavica I Kujundzić M Tadić M Banić M Jagić V Marusić M 《Collegium antropologicum》2012,36(1):145-150
The diagnosis and staging of acute cholecystitis, upon a lot of diagnostic methods and some scoring systems, is still a great clinical problem. The aim of the study was to investigate if serum Troponin I is elevated in patients with acute cholecystitis. Following informed consent, 65 patients with clinical and laboratory signs of acute cholecystitis were enrolled. All patients had measured serum Troponin I level and an abdominal ultrasound was done before definitive treatment was performed. Increased serum Troponin I level was found in most patients with severe form of acute cholecystitis (p < 0.00001). It reached sensitivity of 94.5% and specificity of 57.1% of this test. In multiple regression analysis Troponin I significantly correlated (p < 0.05) with the serum aspartate aminotransferase (r = 0.27), gamma-glutamyl transferase (r = 0.25) and gallbladder wall (> 6 mm) thickness (r = 0.58). Our study confirms that in most patients with severe and acute cholecystitis, serum Troponin I is increased. Troponin I level is in a lower range than it would be in patients with cardiac muscle damage or necrosis. Measuring serum Troponin I is a fast, reliable and widely performed test that could, with other routinely measured parameters, help in early diagnosis of the severe form of acute cholecystitis. 相似文献
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6.
Scott Gleim Jeremiah Stitham Wai Ho Tang Hong Li Karen Douville Prashen Chelikani Jeffrey J.Rade Kathleen A. Martin John Hwa 《PloS one》2013,8(6)
Thromboxane and its receptor have emerged as key players in modulating vascular thrombotic events. Thus, a dysfunctional hTP genetic variant may protect against (hypoactivity) or promote (hyperactivity) vascular events, based upon its activity on platelets. After extensive in silico analysis, six hTP-α variants were selected (C68S, V80E, E94V, A160T, V176E, and V217I) for detailed biochemical studies based on structural proximity to key regions involved in receptor function and in silico predictions. Variant biochemical profiles ranged from severe instability (C68S) to normal (V217I), with most variants demonstrating functional alteration in binding, expression or activation (V80E, E94V, A160T, and V176E). In the absence of patient platelet samples, we developed and validated a novel megakaryocyte based system to evaluate human platelet function in the presence of detected dysfunctional genetic variants. Interestingly, variant V80E exhibited reduced platelet activation whereas A160T demonstrated platelet hyperactivity. This report provides the most comprehensive in silico, in vitro and “in platelet” evaluation of hTP variants to date and highlightscurrent inherent problems in evaluating genetic variants, with possible solutions. The study additionally provides clinical relevance to characterized dysfunctional hTP variants. 相似文献
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8.
A. W. Thompson A. I. Furness C. Stone C. M. Rade G. Ortí 《Journal of fish biology》2017,91(1):126-143
This study investigates zona pellucida (ZP) ultrastructure in fertilized eggs of annual killifishes (suborder Aplocheiloidei), a group of highly specialized fishes that are able to survive desiccation for several weeks to months before they hatch. Little is known about ZP or chorionic ultrastructure sustaining these life‐history modes, so scanning electron microscopy (SEM) was used to describe this trait in a large number of aplocheiloids with a focus on the family Rivulidae and the genus Hypsolebias. New images of ZP ultrastructure for 52 aplocheiloid species are provided, more than doubling the number characterized thus far. The evolution of chorionic structure within this group is studied using these new data. Characters were coded into a morphological matrix and optimized onto a consensus phylogeny to assess phylogenetic signal and reconstruct ancestral character states. Although ZP characters seem highly homoplastic and exhibit a large amount of structural convergence among lineages, aplocheiloid killifishes have evolved a number of unique structures associated with the chorion. Some annual species seem to have lost long filaments because eggs are deposited in the soil instead of being adhered to aquatic plants. 相似文献
9.
Background
Previous studies indicated that recombinant gas vesicles (r-GV) from a mutant strain of Halobacterium sp. NRC-1 could express a cassette containing test sequences of SIVmac gag derived DNA, and function as an antigen display/delivery system. Tests using mice indicated that the humoral immune response to the gag encoded sequences evoked immunologic memory in the absence of an exogenous adjuvant.Results
The goal of this research was to extend this demonstration to diverse gene sequences by testing recombinant gas vesicles displaying peptides encoded by different SIV genes (SIV tat, rev or nef ). Verification that different peptides can be successfully incorporated into the GvpC surface protein of gas vesicle would support a more general biotechnology application of this potential display/delivery system. Selected SIVsm-GvpC fusion peptides were generated by creating and expressing fusion genes, then assessing the resulting recombinant gas vesicles for SIV peptide specific antigenic and immunogenic capabilities. Results from these analyses support three conclusions: (i) Different recombinant gvpC-SIV genes will support the biosynthesis of chimeric, GvpC fusion proteins which are incorporated into the gas vesicles and generate functional organelles. (ii) Monkey antibody elicited by in vivo infection with SHIV recognizes these expressed SIV sequences in the fusion proteins encoded by the gvpC-SIV fusion genes as SIV peptides. (iii) Test of antiserum elicited by immunizing mice with recombinant gas vesicles demonstrated notable and long term antibody titers. The observed level of humoral responses, and the maintenance of elevated responses to, Tat, Rev and Nef1 encoded peptides carried by the respective r-GV, are consistent with the suggestion that in vivo there may be a natural and slow release of epitope over time.Conclusion
The findings therefore suggest that in addition to providing information about these specific inserts, r-GV displaying peptide inserts from other relevant pathogens could have significant biotechnological potential for display and delivery, or serve as a cost effective initial screen of pathogen derived peptides naturally expressed during infections in vivo. 相似文献10.
Peterlin-Masic L Kranjc A Marinko P Mlinsek G Solmajer T Stegnar M Kikelj D 《Bioorganic & medicinal chemistry letters》2003,13(19):3171-3176
Novel, highly selective and potent thrombin inhibitors were identified as a result of combing the 3-benzylsulfonylamino-2-pyridinone acetamide P(2)-P(3) surrogate with weakly basic partially saturated heterobicyclic P(1)-arginine mimetics 1-8. The design, synthesis, biological activity, and the binding modes of non-covalent thrombin inhibitors featuring P(1)-4,5,6,7-tetrahydroindazole, 5,6,7,8-tetrahydroquinazoline, and 4,5,6,7-tetrahydrobenzothiazole moieties are described. 相似文献