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81.
Ramasamy Santhamani Revanaiah Yogisharadhya Gnanavel Venkatesan Sathish Bhadravati Shivachandra Awadh Bihari Pandey Muthannan Andavar Ramakrishnan 《Virus genes》2014,49(2):286-291
Sheeppox and goatpox are economically important diseases of small ruminants caused by sheeppox virus (SPPV) and goatpox virus (GTPV), respectively. Although SPPV and GTPV have host preference, some strains may infect both sheep and goats. As capripox viruses (SPPV, GTPV and LSDV) are antigenically related but genetically distinct, their differentiation requires analysis at molecular level. In the present study, RPO30 and GPCR genes of eight Indian SPPV and GTPV isolates were PCR amplified, cloned and sequences are genetically and phylogenetically analyzed. The RPO30 gene of SPPV and GTPV had lineage-specific signatures, and deletion of 21-nucleotide exclusively present in SPPV. Similarly, GPCR gene also had lineage-specific signatures for SPPV and GTPV. Phylogenetic analysis of capripox viruses based on RPO30 and GPCR genes revealed three distinct lineage-specific clusters as per their host origin. Our study supports that both RPO30 and GPCR genes could be used for differentiation of SPPV and GTPV as well as for molecular epidemiological studies. The study also highlights the distinct lineage specificities of the Indian SPPV and GTPV isolates including vaccine strains. 相似文献
82.
Nagarajan Ramakrishnan Bhuvaneshwari Shankar Lakshmi Ranganathan D. K. Daphnee Adithya Bharadwaj Ramesh Venkataraman 《Indian Journal of Critical Care Medicine》2016,20(1):36-39
Background:Enteral nutrition (EN) is preferred over parenteral nutrition (PN) in hospitalized patients based on International consensus guidelines. Practice patterns of PN in developing countries have not been documented.Objectives:To assess practice pattern and quality of PN support in a tertiary hospital setting in Chennai, India.Methods:Retrospective record review of patients admitted between February 2010 and February 2012.Results:About 351,008 patients were admitted to the hospital in the study period of whom 29,484 (8.4%) required nutritional support. About 70 patients (0.24%) received PN, of whom 54 (0.18%) received PN for at least three days. Common indications for PN were major gastrointestinal surgery (55.6%), intolerance to EN (25.9%), pancreatitis (5.6%), and gastrointestinal obstruction (3.7%).Conclusions:The proportion of patients receiving PN was very low. Quality issues were identified relating to appropriateness of indication and calories and proteins delivered. This study helps to introspect and improve the quality of nutrition support. 相似文献
83.
Illusory conjunctions in visual short‐term memory: Individual differences in corpus callosum connectivity and splitting attention between the two hemifields 下载免费PDF全文
Shuo Qin Nicholas R. Ray Nithya Ramakrishnan Kaoru Nashiro Margaret A. O'Connell Chandramallika Basak 《Psychophysiology》2016,53(11):1639-1650
Overloading the capacity of visual attention can result in mistakenly combining the various features of an object, that is, illusory conjunctions. We hypothesize that if the two hemispheres separately process visual information by splitting attention, connectivity of corpus callosum—a brain structure integrating the two hemispheres—would predict the degree of illusory conjunctions. In the current study, we assessed two types of illusory conjunctions using a memory‐scanning paradigm; the features were either presented across the two opposite hemifields or within the same hemifield. Four objects, each with two visual features, were briefly presented together followed by a probe‐recognition and a confidence rating for the recognition accuracy. MRI scans were also obtained. Results indicated that successful recollection during probe recognition was better for across hemifields conjunctions compared to within hemifield conjunctions, lending support to the bilateral advantage of the two hemispheres in visual short‐term memory. Age‐related differences regarding the underlying mechanisms of the bilateral advantage indicated greater reliance on recollection‐based processing in young and on familiarity‐based processing in old. Moreover, the integrity of the posterior corpus callosum was more predictive of opposite hemifield illusory conjunctions compared to within hemifield illusory conjunctions, even after controlling for age. That is, individuals with lesser posterior corpus callosum connectivity had better recognition for objects when their features were recombined from the opposite hemifields than from the same hemifield. This study is the first to investigate the role of the corpus callosum in splitting attention between versus within hemifields. 相似文献
84.
In vitro and in vivo correlates of physiological and neoplastic human Fallopian tube stem cells 下载免费PDF全文
85.
Bianca Dimitrov Nastassja Himmelreich Agnes L. Hipgrave Ederveen Christian Lüchtenborg Jürgen G. Okun Maximilian Breuer Anna-Marlen Hutter Matthias Carl Luca Guglielmi Andrea Hellwig Kai Christian Thiemann Markus Jost Verena Peters Christian Staufner Georg F. Hoffmann Annette Hackenberg Nagarajan Paramasivam Stefan Wiemann Christian Thiel 《Molecular genetics and metabolism》2018,123(3):364-374
Congenital disorders of glycosylation (CDG) are genetic defects in the glycoconjugate biosynthesis. > 100 types of CDG are known, most of them cause multi-organ diseases. Here we describe a boy whose leading symptoms comprise cutis laxa, pancreatic insufficiency and hepatosplenomegaly. Whole exome sequencing identified the novel hemizygous mutation c.542 T > G (p.L181R) in the X-linked ATP6AP1, an accessory protein of the mammalian vacuolar H+-ATPase, which led to a general N-glycosylation deficiency. Studies of serum N-glycans revealed reduction of complex sialylated and appearance of truncated diantennary structures. Proliferation of the patient's fibroblasts was significantly reduced and doubling time prolonged. Additionally, there were alterations in the fibroblasts' amino acid levels and the acylcarnitine composition. Especially, short-chain species were reduced, whereas several medium- to long-chain acylcarnitines (C14-OH to C18) were elevated. Investigation of the main lipid classes revealed that total cholesterol was significantly enriched in the patient's fibroblasts at the expense of phophatidylcholine and phosphatidylethanolamine. Within the minor lipid species, hexosylceramide was reduced, while its immediate precursor ceramide was increased. Since catalase activity and ACOX3 expression in peroxisomes were reduced, we assume an ATP6AP1-dependent impact on the β-oxidation of fatty acids. These results help to understand the complex clinical characteristics of this new patient. 相似文献
86.
Deepthi Kappala Ratanti Sarkhel Sunil Kumar Dixit Manish Mahawar Mithilesh Singh Saravanan Ramakrishnan Tapas Kumar Goswami 《Immunobiology》2018,223(6-7):501-507
Bacterial attachment to host cell is the first event for pathogen entry. The attachment is mediated through membrane expressed adhesins present on the organism and receptors on the cell surface of host. The objective of this study was to investigate the significance of Fc receptors (FcRs), actin filament polymerization, mannose receptors (MRs), carbohydrate moieties like N-linked glycans and sialic acid on chicken macrophages for invasion of S. Typhimurium. Opsonisation of S. Typhimurium resulted in three folds more invasion in chicken monocyte derived macrophages. Cytochalasin D, an inhibitor of actin filament polymerization prevented uptake of S. Typhimurium. Pre-incubation of macrophages with cytochalasin D, showed severe decrease (28 folds) in S. Typhimurium invasion. Next we attempted to analyse the role of carbohydrate receptors of macrophages in S. Typhimurium invasion. Treatment of macrophages with methyl α-d-mannopyranoside, PNGase F and neuraminidase, showed 2.5, 5 and 2.5 folds decrease in invasion respectively. Our data suggest that deglycosylation of N-linked glycans including sialic acid by PNGase F is more effective in inhibition of S. Typhimurium invasion than neuraminidase which removes only sialic acid. These findings suggested FcRs, actin filament polymerization, MRs, N-linked glycans and sialic acid may act as gateway for entry of S. Typhimurium. 相似文献
87.
88.
Nagarajan Ramakrishnan D. K. Daphnee Lakshmi Ranganathan S. Bhuvaneshwari 《Indian Journal of Critical Care Medicine》2014,18(3):144-148
Background and Aims:
Adequate nutritional support is crucial in prevention and treatment of malnutrition in critically ill-patients. Despite the intention to provide appropriate enteral nutrition (EN), meeting the full nutritional requirements can be a challenge due to interruptions. This study was undertaken to determine the cause and duration of interruptions in EN.Materials and Methods:
Patients admitted to a multidisciplinary critical care unit (CCU) of a tertiary care hospital from September 2010 to January 2011 and who received EN for a period >24 h were included in this observational, prospective study. A total of 327 patients were included, for a total of 857 patient-days. Reasons and duration of EN interruptions were recorded and categorized under four groups-procedures inside CCU, procedures outside CCU, gastrointestinal (GI) symptoms and others.Results:
Procedure inside CCU accounted for 55.9% of the interruptions while GI symptoms for 24.2%. Although it is commonly perceived that procedures outside CCU are the most common reason for interruption, this contributed only to 18.4% individually; ventilation-related procedures were the most frequent cause (40.25%), followed by nasogastric tube aspirations (15.28%). Although GI bleed is often considered a reason to hold enteral feed, it was one of the least common reasons (1%) in our study. Interruption of 2-6 h was more frequent (43%) and most of this (67.1%) was related to “procedures inside CCU”.Conclusion:
Awareness of reasons for EN interruptions will aid to modify protocol and minimize interruptions during procedures in CCU to reach nutrition goals. 相似文献89.
Tatyana Shamliyan Kristine M.C. Talley Rema Ramakrishnan Robert L. Kane 《Ageing research reviews》2013,12(2):719-736
Frailty is a known risk factor for those aged 65 and over, and its prevalence increases with age. Definitions of frailty vary widely, and prevalence estimates are affected by the way frailty is defined. Systematic reviews have yet to examine the literature on the association between definitions of frailty and mortality.We examined the definitions and prevalence of frailty and its association with survival in older community-dwelling adults. We conducted a systematic review of observational population-based studies published in English. We calculated pooled prevalence of frailty with a random effects model.We identified 24 population-based studies that examined frailty in community-dwelling older adults. The pooled prevalence was 14% when frailty was defined as a phenotype exhibiting three or more of the following: weight loss, fatigue/exhaustion, weakness, low physical activity/slowness, and mobility impairment. The pooled prevalence was 24% when frailty was defined by accumulation of deficits indices that included up to 75 diseases and impairments. The prevalence of frailty increased with age and was greater in women and in African Americans. Frailty in older adults was associated with poor survival with a dose–responsive reduction in survival per increasing number of frailty criteria. Taking into account population prevalence and multivariate adjusted relative risks, we estimated that 3–5% of deaths among older adults could be delayed if frailty was prevented.Frailty is a prevalent and important geriatric syndrome associated with decreased survival. Geriatric assessment of frailty provides clinically important information about functional status and survival of older adults. 相似文献
90.
Srikantan S. Nagarajan Dominique M. Durand Kai Hsuing-Hsu 《Annals of biomedical engineering》1997,25(1):112-125
We determined the location of excitation for different positions of a round and butterfly coil duringin vitro magnetic stimulation of cut peripheral nerves. We analyzed the conditions under which excitation occurs, either at the termination
or at the peak of the field gradients (first spatial derivative of the electric field). These results were then compared to
predictions about the location of excitation sites from a theoretical model of magnetic stimulation of finite neuronal structures.
Excitation along a straight nerve occurred at terminations when 1) a coil was positioned close to the end of a nerve (at least
one diameter length from the end), 2) a nerve ended in a finite terminating impedance much greater than the axial resistance
of the nerve, 3) the induced electric field was of sufficient magnitude, pointing in a direction away from the axis of a nerve.
Excitation occurred at the negative peak of the field gradients along a nerve when 1) a coil was positioned far away from
the ends of a nerve, 2) there were no geometric or volume conductor inhomogeneities around a nerve, and 3) it was of sufficient
magnitude. Threshold strengths for excitation at terminations were significantly lower than that for field gradient excitation
and comparable to that due to geometric and volume conductor inhomogeneities. 相似文献