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231.
Banurekha Velayutham Beena Thomas Dina Nair Kannan Thiruvengadam Suma Prashant Sathyapriya Kittusami Harivanzan Vijayakumar Meenachi Chidambaram Shri Vijay Bala Yogendra Shivakumar Lavanya Jayabal Ashok Jhunjhunwala Soumya Swaminathan 《PloS one》2015,10(9)
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232.
Jiancheng Hu Lalima G. Ahuja Hiruy S. Meharena Natarajan Kannan Alexandr P. Kornev Susan S. Taylor Andrey S. Shaw 《Molecular and cellular biology》2015,35(1):264-276
A new model of kinase regulation based on the assembly of hydrophobic spines has been proposed. Changes in their positions can explain the mechanism of kinase activation. Here, we examined mutations in human cancer for clues about the regulation of the hydrophobic spines by focusing initially on mutations to Phe. We identified a selected number of Phe mutations in a small group of kinases that included BRAF, ABL1, and the epidermal growth factor receptor. Testing some of these mutations in BRAF, we found that one of the mutations impaired ATP binding and catalytic activity but promoted noncatalytic allosteric functions. Other Phe mutations functioned to promote constitutive catalytic activity. One of these mutations revealed a previously underappreciated hydrophobic surface that functions to position the dynamic regulatory αC-helix. This supports the key role of the C-helix as a signal integration motif for coordinating multiple elements of the kinase to create an active conformation. The importance of the hydrophobic space around the αC-helix was further tested by studying a V600F mutant, which was constitutively active in the absence of the negative charge that is associated with the common V600E mutation. Many hydrophobic mutations strategically localized along the C-helix can thus drive kinase activation. 相似文献
233.
X‐ray crystal structures of an orally available aminopeptidase inhibitor,Tosedostat, bound to anti‐malarial drug targets PfA‐M1 and PfA‐M17 下载免费PDF全文
Nyssa Drinkwater Rebecca S. Bamert Komagal Kannan Sivaraman Alessandro Paiardini Sheena McGowan 《Proteins》2015,83(4):789-795
New anti‐malarial treatments are desperately required to face the spread of drug resistant parasites. Inhibition of metalloaminopeptidases, PfA‐M1 and PfA‐M17, is a validated therapeutic strategy for treatment of Plasmodium falciparum malaria. Here, we describe the crystal structures of PfA‐M1 and PfA‐M17 bound to chemotherapeutic agent Tosedostat. The inhibitor occupies the enzymes' putative product egress channels in addition to the substrate binding pockets; however, adopts different binding poses when bound to PfA‐M1 and PfA‐M17. These findings will be valuable for the continued development of selective inhibitors of PfA‐M1 and PfA‐M17. Proteins 2015; 83:789–795. © 2015 Wiley Periodicals, Inc. 相似文献
234.
Krishnadev Oruganty Natarajan Kannan 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(7):1322-1329
The activation of protein kinases involves conformational changes in key functional regions of the kinase domain, a detailed understanding of which is essential for the design of selective protein kinase inhibitors. Through statistical analysis of protein kinase sequences and crystal structures from diverse organisms, we recently proposed that the activation of protein kinases involves a hidden strain switch in the catalytic loop. Specifically, we demonstrated that the backbone torsion-angles of residues in the catalytic loop switch from a “relaxed” to “strained” conformation upon kinase activation and the strained geometry results in a network of hydrogen bonds involving conserved non-catalytic residues in the ATP and substrate binding lobes. Here, we further explore this activation mechanism by analyzing families that lack the canonical hydrogen bonding interactions with the strained backbone. We find that alternative mechanisms have evolved to maintain catalytic loop strain. In PIM kinase, for example, two water molecules account for the lack of a conserved aspartate in the substrate binding by hydrogen bonds to the strained backbone. We discuss the relevance of these findings in the design of family-specific allosteric inhibitors, and in predicting the structural and functional impact of cancer mutations that alter the strain associated hydrogen bonding network. This article is part of a Special Issue entitled: Inhibitors of Protein Kinases (2012). 相似文献
235.
Nagarajan Baskaran Govindarajan Kannan Uthrapathy Anbarasan Anisha Thapa Raman Sukumar 《Mammalian Biology》2013,78(6):470-481
Spatial information at the landscape scale is extremely important for conservation planning, especially in the case of long-ranging vertebrates. The biodiversity-rich Anamalai hill ranges in the Western Ghats of southern India hold a viable population for the long-term conservation of the Asian elephant. Through rapid but extensive field surveys we mapped elephant habitat, corridors, vegetation and land-use patterns, estimated the elephant population density and structure, and assessed elephant–human conflict across this landscape. GIS and remote sensing analyses indicate that elephants are distributed among three blocks over a total area of about 4600 km2. Approximately 92% remains contiguous because of four corridors; however, under 4000 km2 of this area may be effectively used by elephants. Nine landscape elements were identified, including five natural vegetation types, of which tropical moist deciduous forest is dominant. Population density assessed through the dung count method using line transects covering 275 km of walk across the effective elephant habitat of the landscape yielded a mean density of 1.1 (95% CI = 0.99–1.2) elephant/km2. Population structure from direct sighting of elephants showed that adult male elephants constitute just 2.9% and adult females 42.3% of the population with the rest being sub-adults (27.4%), juveniles (16%) and calves (11.4%). Sex ratios show an increasing skew toward females from juvenile (1:1.8) to sub-adult (1:2.4) and adult (1:14.7) indicating higher mortality of sub-adult and adult males that is most likely due to historical poaching for ivory. A rapid questionnaire survey and secondary data on elephant–human conflict from forest department records reveals that villages in and around the forest divisions on the eastern side of landscape experience higher levels of elephant–human conflict than those on the western side; this seems to relate to a greater degree of habitat fragmentation and percentage farmers cultivating annual crops in the east. We provide several recommendations that could help maintain population viability and reduce elephant–human conflict of the Anamalai elephant landscape. 相似文献
236.
Hiruy S. Meharena Philip Chang Malik M. Keshwani Krishnadev Oruganty Aishwarya K. Nene Natarajan Kannan Susan S. Taylor Alexandr P. Kornev 《PLoS biology》2013,11(10)
Eukaryotic protein kinases (EPKs) regulate numerous signaling processes by phosphorylating targeted substrates through the highly conserved catalytic domain. Our previous computational studies proposed a model stating that a properly assembled nonlinear motif termed the Regulatory (R) spine is essential for catalytic activity of EPKs. Here we define the required intramolecular interactions and biochemical properties of the R-spine and the newly identified “Shell” that surrounds the R-spine using site-directed mutagenesis and various in vitro phosphoryl transfer assays using cyclic AMP-dependent protein kinase as a representative of the entire kinome. Analysis of the 172 available Apo EPK structures in the protein data bank (PDB) revealed four unique structural conformations of the R-spine that correspond with catalytic inactivation of various EPKs. Elucidating the molecular entities required for the catalytic activation of EPKs and the identification of these inactive conformations opens new avenues for the design of efficient therapeutic EPK inhibitors. 相似文献
237.
Veeraperumal Suresh Namasivayam Senthilkumar Ramar Thangam Mayan Rajkumar Chinnathambi Anbazhagan Ramasamy Rengasamy Palani Gunasekaran Soundarapandian Kannan Perumal Palani 《Process Biochemistry》2013,48(2):364-373
Sulfated polysaccharides (SPs) were identified in different portions of the thallus of Sargassum plagiophyllum C. Agardh, with TBO staining. SPs were extracted using a blade and purified by Q sepharose fast flow anion-exchange chromatography, resulting in SP fractions F1, F2 and F3, with molecular weights of 30, 35 and 20 kDa, respectively. An SP yield of 43.1% was obtained in F3, while F2 yielded a sulfate content of 21.9%. Furthermore, the in vitro anticancer and antioxidant activities of the polysaccharide fractions were evaluated. The F2 fraction showed higher anticancer activity against HepG2 and A549 cells than the other two fractions, with IC50 values of 600 μg/mL and 700 μg/mL, respectively. The normal breast epithelial cell line (HBL-100) exhibited IC50 concentrations of 1200 and 1400 μg/mL for crude sulfated polysaccharides (CSPs) and all SP fractions (F1–F3). These results indicated that the anticancer activity of F2 could be related to its sulfate content. However, the antioxidant activities of F1–F3 were low at their tested concentrations. 相似文献
238.
Victor John Sundar Arumugam Gnanamani Chellappa Muralidharan Narasiman Kannan Chandrababu Asit Baran Mandal 《Reviews in Environmental Science and Biotechnology》2011,10(2):151-163
Hides and skins, by-product of the meat industry is converted into a value added product namely leather by the tanners. Tanning
essentially is the process of converting raw hides and skins into imputrescible substance. The tanning process has number
of steps and generates significant quantities of by products and wastes. These solid and liquid wastes pose major environmental
problem if not managed effectively. Large–scale production systems are adopted for leather processing in clusters and therefore,
the industry receives focus of environmentalists and society. Consequently tremendous pressure is exerted by various pollution
regulatory bodies. The hides and skins, after trimming, removal of flesh and fat, are treated with chemicals, which cross-link
the collagen fibers to form a stable, durable material. The chemicals used may be derived from traditional vegetable products,
or inorganic metal salts. During leather processing number of size reduction, leveling and purification operations are carried
out which results in generation of untanned and tanned proteinous waste materials. In this paper, various recovery processes
and utilization methodologies of proteinous solid wastes, emanating from leather processing operations prior to tanning is
reviewed. 相似文献
239.
Pati A Abt B Teshima H Nolan M Lapidus A Lucas S Hammon N Deshpande S Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Mavromatis K Ovchinikova G Chen A Palaniappan K Land M Hauser L Jeffries CD Detter JC Brambilla EM Kannan KP Rohde M Spring S Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Ivanova N 《Standards in genomic sciences》2011,4(2):221-232
Cellulophaga lytica (Lewin 1969) Johansen et al. 1999 is the type species of the genus Cellulophaga, which belongs to the family Flavobacteriaceae within the phylum 'Bacteroidetes' and was isolated from marine beach mud in Limon, Costa Rica. The species is of biotechnological interest because its members produce a wide range of extracellular enzymes capable of degrading proteins and polysaccharides. After the genome sequence of Cellulophaga algicola this is the second completed genome sequence of a member of the genus Cellulophaga. The 3,765,936 bp long genome with its 3,303 protein-coding and 55 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
240.
Candida albicans is a commensal opportunistic pathogen, which can cause superficial infections as well as systemic infections in immuocompromised hosts. Among nosocomial fungal infections, infections by C. albicans are associated with highest mortality rates even though incidence of infections by other related species is on the rise world over. Since C. albicans and other Candida species differ in their susceptibility to antifungal drug treatment, it is crucial to accurately identify the species for effective drug treatment. Most diagnostic tests that differentiate between C. albicans and other Candida species are time consuming, as they necessarily involve laboratory culturing. Others, which employ highly sensitive PCR based technologies often, yield false positives which is equally dangerous since that leads to unnecessary antifungal treatment. This is the first report of phage display technology based identification of short peptide sequences that can distinguish C. albicans from other closely related species. The peptides also show high degree of specificity towards its different morphological forms. Using fluorescence microscopy, we show that the peptides bind on the surface of these cells and obtained clones that could even specifically bind to only specific regions of cells indicating restricted distribution of the epitopes. What was peculiar and interesting was that the epitopes were carbohydrate in nature. This gives insight into the complexity of the carbohydrate composition of fungal cell walls. In an ELISA format these peptides allow specific detection of relatively small numbers of C. albicans cells. Hence, if used in combination, such a test could help accurate diagnosis and allow physicians to initiate appropriate drug therapy on time. 相似文献