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41.
Uropathogenic Escherichia coli (UPEC) causes serious infections in people at risk and has a significant environmental prevalence due to contamination by human and animal excreta. In developing countries, UPEC assumes importance in certain dwellings because of poor community/personal hygiene and exposure to contaminated water or soil. We report the complete genome sequence of E. coli strain NA114 from India, a UPEC strain with a multidrug resistance phenotype and the capacity to produce extended-spectrum beta-lactamase. The genome sequence and comparative genomics emanating from it will be significant in under-standing the genetic makeup of diverse UPEC strains and in boosting the development of new diagnostics/vaccines.  相似文献   
42.
The Opuntia cochineal scale or false carmine cochineal scale, Dactylopius opuntiae (Cockerell) (Hemiptera: Dactylopiidae), is spreading rapidly in many countries, especially in the Mediterranean basin, where it has become a serious pest of prickly pear crops, Opuntia ficus‐indica (L.) Miller (Cactaceae). This crop is an important food resource both for humans and livestock. The cochineal was originally used as a biological agent to control cactaceous weeds in many countries where Opuntiaceae had been introduced. Currently, in some countries where the prickly pear is no longer considered a weed but a productive crop, as in the Mediterranean area, D. opuntiae has changed its role from a highly prized biological control agent to the status of serious pest. This paper provides an overview of the current knowledge on D. opuntiae for farmers and stakeholders in order to indicate the most appropriate way to limit or counteract the spread of this pest especially in new cultivated areas.  相似文献   
43.
The demand for increased formulation concentrations for protein therapeutics puts a significant strain on already existing tangential flow filtration (TFF) systems that were constructed with lower protein concentration targets as part of their design criteria. TFF is commonly used to buffer exchange and concentrate the product to the appropriate drug substance concentration. Analyzing the ability of an existing TFF system to process under conditions outside its original design specifications can be challenging. In this analysis, we present a systematic approach to assess the operational limits of a TFF process with consideration of system performance parameters for changing process targets. In two new engineering diagrams, the recovery efficiency diagram and the operating space plot, all relevant operational constraints and parameters are related to allow rapid process fit evaluation. The engineering assessment of TFF systems presented in this article allows a rational review of system limitations during process fit evaluations of existing TFF systems. It also provides a rational basis for targeted system upgrades and setting system design specifications for the design of new systems if existing systems are found inadequate. Biotechnol. Bioeng. 2012; 109: 3084–3092. © 2012 Wiley Periodicals, Inc.  相似文献   
44.
Marine compound database consists of marine natural products and chemical entities, collected from various literature sources, which are known to possess bioactivity against human diseases. The database is constructed using html code. The 12 categories of 182 compounds are provided with the source, compound name, 2-dimensional structure, bioactivity and clinical trial information. The database is freely available online and can be accessed at http://www.progenebio.in/mcdb/index.htm  相似文献   
45.
Traditional fermentation systems employed by rural people of India were initially screened for phytate-hydrolysing microbes on solid medium supplemented with calcium phytate. It was followed by enzyme assay of culture filtrates to differentiate the phytase-producing microbes. Three new microbial genera are added to the list of phytase-producing organisms.  相似文献   
46.
Tropomyosin represents a major allergen of decapod crustaceans such as shrimps and crabs, and its highly conserved amino acid sequence (>90% identity) is a molecular basis of the immunoglobulin E (IgE) cross-reactivity among decapods. At present, however, little information is available about allergens in edible crustaceans other than decapods. In this study, the major allergen in two species of edible crustaceans, Antarctic krill Euphausia superba and mantis shrimp Oratosquilla oratoria that are taxonomically distinct from decapods, was demonstrated to be tropomyosin by IgE-immunoblotting using patient sera. The cross-reactivity of the tropomyosins from both species with decapod tropomyosins was also confirmed by inhibition IgE immunoblotting. Sequences of the tropomyosins from both species were determined by complementary deoxyribonucleic acid cloning. The mantis shrimp tropomyosin has high sequence identity (>90% identity) with decapod tropomyosins, especially with fast-type tropomyosins. On the other hand, the Antarctic krill tropomyosin is characterized by diverse alterations in region 13–42, the amino acid sequence of which is highly conserved for decapod tropomyosins, and hence, it shares somewhat lower sequence identity (82.4–89.8% identity) with decapod tropomyosins than the mantis shrimp tropomyosin. Quantification by enzyme-linked immunosorbent assay revealed that Antarctic krill contains tropomyosin at almost the same level as decapods, suggesting that its allergenicity is equivalent to decapods. However, mantis shrimp was assumed to be substantially not allergenic because of the extremely low content of tropomyosin.  相似文献   
47.
In the present work, the mechanism of the interaction between a β1 receptor blocker, metoprolol succinate (MS) and human serum albumin (HSA) under physiological conditions was investigated by spectroscopic techniques, namely fluorescence, Fourier transform infra‐red spectroscopy (FT‐IR), fluorescence lifetime decay and circular dichroism (CD) as well as molecular docking and cyclic voltammetric methods. The fluorescence and lifetime decay results indicated that MS quenched the intrinsic intensity of HSA through a static quenching mechanism. The Stern–Volmer quenching constants and binding constants for the MS–HSA system at 293, 298 and 303 K were obtained from the Stern–Volmer plot. Thermodynamic parameters for the interaction of MS with HSA were evaluated; negative values of entropy change (ΔG°) indicated the spontaneity of the MS and HSA interaction. Thermodynamic parameters such as negative ΔH° and positive ΔS° values revealed that hydrogen bonding and hydrophobic forces played a major role in MS–HSA interaction and stabilized the complex. The binding site for MS in HSA was identified by competitive site probe experiments and molecular docking studies. These results indicated that MS was bound to HSA at Sudlow's site I. The efficiency of energy transfer and the distance between the donor (HSA) and acceptor (MS) was calculated based on the theory of Fosters' resonance energy transfer (FRET). Three‐dimensional fluorescence spectra and CD results revealed that the binding of MS to HSA resulted in an obvious change in the conformation of HSA. Cyclic voltammograms of the MS–HSA system also confirmed the interaction between MS and HSA. Furthermore, the effects of metal ions on the binding of MS to HSA were also studied.  相似文献   
48.

Introduction

Tuberculosis (TB) is a notifiable disease and health care providers are required to notify every TB case to local authorities. We conducted a pilot study to determine the usefulness and feasibility of mobile interface in TB notification (MITUN) voice based system for notification of TB cases by private medical practitioners.

Methodology

The study was conducted during September 2013 to October 2014 in three zones of Chennai, an urban setting in South India. Private clinics wherein services are provided by single private medical practitioners were approached. The steps involved in MITUN included: Registration of the practitioners and notification of TB cases by them through voice interactions. Pre and post-intervention questionnaires were administered to collect information on TB notification practices and feasibility of MITUN after an implementation period of 6 months.

Results

A total of 266 private medical practitioners were approached for the study. Of them, 184 (69%) participated in the study; of whom 11 (6%) practitioners used MITUN for TB notification. Reasons for not using MITUN include lack of time, referral of patients to government facility, issues related to patient confidentiality and technical problems. Suggestions for making mobile phone based TB notification process user-friendly included reducing call duration, including only crucial questions and using missed call or SMS options.

Conclusion

The performance (feasibility and usefulness) of MITUN voice based system for TB notification in the present format was sub-optimal. Perceived problems, logistical and practical issues preclude scale–up of notification of TB by private practitioners.  相似文献   
49.
Protection against microbial pathogens involves the activation of cellular immune responses in eukaryotes, and this cellular immunity likely involves changes in subcellular membrane trafficking. In eukaryotes, members of the Rab GTPase family of small monomeric regulatory GTPases play prominent roles in the regulation of membrane trafficking. We previously showed that RabA4B is recruited to vesicles that emerge from trans-Golgi network (TGN) compartments and regulates polarized membrane trafficking in plant cells. As part of this regulation, RabA4B recruits the closely related phosphatidylinositol 4-kinase (PI4K) PI4Kβ1 and PI4Kβ2 lipid kinases. Here, we identify a second Arabidopsis thaliana RabA4B-interacting protein, PLANT U-BOX13 (PUB13), which has recently been identified to play important roles in salicylic acid (SA)-mediated defense signaling. We show that PUB13 interacts with RabA4B through N-terminal domains and with phosphatidylinositol 4-phosphate (PI-4P) through a C-terminal armadillo domain. Furthermore, we demonstrate that a functional fluorescent PUB13 fusion protein (YFP-PUB13) localizes to TGN and Golgi compartments and that PUB13, PI4Kβ1, and PI4Kβ2 are negative regulators of SA-mediated induction of pathogenesis-related gene expression. Taken together, these results highlight a role for RabA4B and PI-4P in SA-dependent defense responses.  相似文献   
50.
An assay method has been developed for the measurement of tissue levels of S-adenosylmethionine based upon the ability of this compound to activate tripolyphosphatase associated with S-adenosylmethionine synthetase beta prepared from rat liver. The method has been used to measure S-adenosylmethionine levels in rat liver after feeding rats on various concentrations of methionine in the diet. The results obtained by this method agree well with those measured by the spectrophotometric method. The limit of sensitivity of the assay was about 0.1 nmol of S-adenosylmethionine in an incubation volume of 0.1 ml (10(-6) M).  相似文献   
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