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991.
992.
Vandana Prasad Indra Bir Singh Sunil Bajpai Rahul Garg Biswajeet Thakur Abha Singh Nachiappan Saravanan Vivesh Vir Kapur 《Facies》2013,59(4):737-761
Geological records of early Paleogene warming are rare in low latitudinal regions. The Indian subcontinent preserves records of this global event on western and eastern margins. We attempt to decipher paleoenvironmental setup and facies architecture of the paleo-equatorial early Eocene succession at the Vastan Lignite Mine, Gulf of Cambay, western India. The Vastan lignite succession was deposited in a low-energy coastal marsh-bay complex receiving only fine-grained muddy sediments from the weathered Deccan Traps. The lower part of the Vastan lignite deposit, designated as “Vastan Succession A”, comprises four depositional facies representing distinct environments (open bay, restricted bay, creek and channel, and coastal marsh) and one diagenetic facies. Palynofacies analysis, backed by precise sedimentological framework, records changes in terrestrial supply and fluctuating marine characters of bay and marshes. Eleven Palyno-Units are identified in distinct lithofacies sequences stacked in shallowing-upward cycles representing five parasequences that constitute a Transgressive Systems Tract (TST) deposit. Each parasequence starts with a transgressive sheet deposit, followed by shallowing-upward bay fill-marsh deposits. In the vertical succession, each parasequence acquires increasing marine character, culminating in a maximum flooding surface (shell carbonate) that represents large-scale coastal onlap during early Ypresian time. The TST is followed by a Highstand Systems Tract deposit, which shows an erosional surface at the top of the upper lignite indicating Lowstand Systems Tract and a sequence boundary at ~52 Ma. The Vastan Succession A represents TST (3rd-order cycle) deposits with parasequences and hemicycles representing 4th- and 5th-order cycles. The study demonstrates sea level rise along the Indian western coastal margin in response to early Eocene warming between ~55 and ~52 Ma with maximum transgression at 53.7 Ma. 相似文献
993.
Katie Stone Emily Woods Susann M. Szmania Owen W. Stephens Tarun K. Garg Bart Barlogie John D. Shaughnessy Jr Brett Hall Manjula Reddy Antje Hoering Emily Hansen Frits van Rhee 《PloS one》2013,8(1)
Multicentric Castleman Disease is largely driven by increased signaling in the pathway for the plasma cell growth factor interleukin-6. We hypothesized that interleukin-6/interleukin-6 receptor/gp130 polymorphisms contribute to increased interleukin-6 and/or other components of the interleukin-6 signaling pathway in HIV-negative Castleman Disease patients. The study group was composed of 58 patients and 50 healthy donors of a similar racial/ethnic profile. Of seven polymorphisms chosen for analysis, we observed an increased frequency between patients and controls of the minor allele of interleukin-6 receptor polymorphism rs4537545, which is in linkage disequilibrium with interleukin-6 receptor polymorphism rs2228145. Further, individuals possessing at least one copy of the minor allele of either polymorphism expressed higher levels of soluble interleukin-6 receptor. These elevated interleukin-6 receptor levels may contribute to increased interleukin-6 activity through the trans-signaling pathway. These data suggest that interleukin-6 receptor polymorphism may be a contributing factor in Castleman Disease, and further research is warranted. 相似文献
994.
Sclerotinia rot caused by Sclerotinia sclerotiorum is one of the most serious diseases of oilseed rape. To understand the resistance mechanisms in the Brassica napus to S. sclerotiorum, comparative disease progression, histological and proteomic studies were conducted of two B. napus genotypes (resistant cv. Charlton, susceptible cv. RQ001-02M2). At 72 and 96 h post inoculation (hpi), lesion size on cotyledons was significantly (P≤0.001) smaller in the resistant Charlton. Anatomical investigations revealed impeded fungal growth (at 24 hpi and onwards) and hyphal disintegration only on resistant Charlton. Temporal changes (12, 24, 48 and 72 hpi) in protein profile showed certain enzymes up-regulated only in resistant Charlton, such as those related to primary metabolic pathways, antioxidant defence, ethylene biosynthesis, pathogenesis related proteins, protein synthesis and protein folding, play a role in mediating defence responses against S. sclerotiorum. Similarly a eukaryotic translation initiation factor 5A enzyme with increased abundance in susceptible RQ001-02M2 and decreased levels in resistant Charlton has a role in increased susceptibility to this pathogen. This is the first time that the expression of these enzymes has been shown to be associated with mediating the defence response against S. sclerotinia in cotyledon tissue of a resistant cultivar of B. napus at a proteomics level. This study not only provides important new insights into the resistance mechanisms within B. napus against S. sclerotiorum, but opens the way for novel engineering of new B. napus varieties that over-express these key enzymes as a strategy to enhance resistance and better manage this devastating pathogen. 相似文献
995.
Monisha Dhiman Yun A. Coronado Cecilia K. Vallejo John R. Petersen Adetoun Ejilemele Sonia Nu?ez Maria Paola Zago Heidi Spratt Nisha Jain Garg 《PLoS neglected tropical diseases》2013,7(8)
Background
We investigated the pathological and diagnostic role of selected markers of inflammation, oxidant/antioxidant status, and cellular injury in human Chagas disease.Methods
Seropositive/chagasic subjects characterized as clinically-symptomatic or clinically-asymptomatic (n = 116), seronegative/cardiac subjects (n = 102), and seronegative/healthy subjects (n = 45) were analyzed for peripheral blood biomarkers.Results
Seropositive/chagasic subjects exhibited an increase in sera or plasma levels of myeloperoxidase (MPO, 2.8-fold), advanced oxidation protein products (AOPP, 56%), nitrite (5.7-fold), lipid peroxides (LPO, 12–17-fold) and malondialdehyde (MDA, 4–6-fold); and a decline in superoxide dismutase (SOD, 52%) and glutathione (GSH, 75%) contents. Correlation analysis identified a significant (p<0.001) linear relationship between inflammatory markers (AOPP/nitrite: r = 0.877), inflammation and antioxidant/oxidant status (AOPP/glutathione peroxidase (GPX): r = 0.902, AOPP/GSH: r = 0.806, Nitrite/GPX: 0.773, Nitrite/LPO: 0.805, MDA/MPO: 0.718), and antioxidant/oxidant levels (GPX/MDA: r = 0.768) in chagasic subjects. Of these, MPO, LPO and nitrite biomarkers were highly specific and sensitive for distinguishing seropositive/chagasic subjects from seronegative/healthy controls (p<0.001, training and fitting AUC/ROC >0.95). The MPO (r = 0.664) and LPO (r = 0.841) levels were also correlated with clinical disease state in chagasic subjects (p<0.001). Seronegative/cardiac subjects exhibited up to 77% decline in SOD, 3–5-fold increase in LPO and glutamate pyruvate transaminase (GPT) levels, and statistically insignificant change in MPO, AOPP, MDA, GPX, GSH, and creatine kinase (CK) levels.Conclusions
The interlinked effects of innate immune responses and antioxidant/oxidant imbalance are major determinants of human Chagas disease. The MPO, LPO and nitrite are excellent biomarkers for diagnosing seropositive/chagasic subjects, and MPO and LPO levels have potential utility in identifying clinical severity of Chagas disease. 相似文献996.
Topical gene delivery to the epidermis has the potential to be an effective therapy for skin disorders, cutaneous cancers, vaccinations and systemic metabolic diseases. Previously, we reported on a non-invasive multielectrode array (MEA) that efficiently delivered plasmid DNA and enhanced expression to the skin of several animal models by in vivo gene electrotransfer. Here, we characterized plasmid DNA delivery with the MEA in a hairless guinea pig model, which has a similar histology and structure to human skin. Significant elevation of gene expression up to 4 logs was achieved with intradermal DNA administration followed by topical non-invasive skin gene electrotransfer. This delivery produced gene expression in the skin of hairless guinea pig up to 12 to 15 days. Gene expression was observed exclusively in the epidermis. Skin gene electrotransfer with the MEA resulted in only minimal and mild skin changes. A low level of human Factor IX was detected in the plasma of hairless guinea pig after gene electrotransfer with the MEA, although a significant increase of Factor IX was obtained in the skin of animals. These results suggest gene electrotransfer with the MEA can be a safe, efficient, non-invasive skin delivery method for skin disorders, vaccinations and potential systemic diseases where low levels of gene products are sufficient. 相似文献
997.
Objectives
To perform a systematic review of randomized controlled trials to determine whether prevention or slowing of progression of chronic kidney disease would translate into improved mortality, and if so, the attributable risk due to CKD itself on mortality.Background
CKD is associated with increased mortality. This association is largely based on evidence from the observational studies and evidence from randomized controlled trials is lacking.Methods
We searched Ovid, Medline and Embase for RCTs in which an intervention was given to prevent or slow the progression of CKD and mortality was reported as primary, secondary or adverse outcomes were eligible and selected. For the first phase, pooled relative risks for renal endpoints were assessed. For the second phase, we assessed the effect on mortality in trials of interventions that definitively reduced CKD endpoints.Results
Among 52 studies selected in first phase, only renin-angiotensin-aldosterone-system blockade vs. placebo (n = 18 trials, 32,557 participants) met the efficacy criteria for further analysis in the second phase by reducing renal endpoints 15 to 27% compared to placebo. There was no difference in all-cause mortality (RR 0.99, 95% CI 0.92 to 1.08) or CV death (RR 0.97, 95% CI 0.78 to 1.21) between the treatment and control groups in these trials. There was sufficient statistical power to detect a 9% relative risk reduction in all-cause mortality and a 14% relative risk reduction in cardiovascular mortality.Conclusions
Firm evidence is lacking that prevention of CKD translates into reductions in mortality. Larger trials with longer follow-up time are needed to determine the benefit of CKD prevention on survival. 相似文献998.
Context
Treatment Resistant Depression (TRD) is a significant and burdensome health concern.Objective
To characterize, compare and understand the difference between TRD and non-TRD patients and episodes in respect of their episode duration, treatment patterns and healthcare resource utilization.Design and Setting
Patients between 18 and 64 years with a new diagnosis of major depressive disorder (MDD) and without a previous or comorbid diagnosis of schizophrenia or bipolar disease were included from PharMetrics Integrated Database, a claims database of commercial insurers in the US. Episodes of these patients in which there were at least two distinct failed regimens involving antidepressants and antipsychotics were classified as TRD.Patients
82,742 MDD patients were included in the analysis; of these patients, 125,172 episodes were identified (47,654 of these were drug-treated episodes).Main Outcome Measures
Comparison between TRD and non-TRD episodes in terms of their duration, number and duration of lines of treatment, comorbidities, and medical resource utilization.Results
Of the treated episodes, 6.6% (N = 3,134) met the criteria for TRD. The median time to an episode becoming TRD was approximately one year. The mean duration of a TRD episode was 1,004 days (vs. 452 days for a non-TRD episode). More than 75% of TRD episodes had at least four lines of therapy; half of the treatment regimens included a combination of drugs. Average hospitalization costs were higher for TRD than non-TRD episodes: $6,464 vs. $1,734, as were all other health care utilization costs.Conclusions
While this study was limited to relatively young and commercially covered patients, used a rigorous definition of TRD and did not analyze for cause or consequence, the results highlight high unmet medical need and burden of TRD on patients and health care resources. 相似文献999.
Donald E. Curtis Christopher S. Hlady Gaurav Kanade Sriram V. Pemmaraju Philip M. Polgreen Alberto M. Segre 《PloS one》2013,8(12)
We present a comprehensive approach to using electronic medical records (EMR) for constructing contact networks of healthcare workers in a hospital. This approach is applied at the University of Iowa Hospitals and Clinics (UIHC) – a 3.2 million square foot facility with 700 beds and about 8,000 healthcare workers – by obtaining 19.8 million EMR data points, spread over more than 21 months. We use these data to construct 9,000 different healthcare worker contact networks, which serve as proxies for patterns of actual healthcare worker contacts. Unlike earlier approaches, our methods are based on large-scale data and do not make any a priori assumptions about edges (contacts) between healthcare workers, degree distributions of healthcare workers, their assignment to wards, etc. Preliminary validation using data gathered from a 10-day long deployment of a wireless sensor network in the Medical Intensive Care Unit suggests that EMR logins can serve as realistic proxies for hospital-wide healthcare worker movement and contact patterns. Despite spatial and job-related constraints on healthcare worker movement and interactions, analysis reveals a strong structural similarity between the healthcare worker contact networks we generate and social networks that arise in other (e.g., online) settings. Furthermore, our analysis shows that disease can spread much more rapidly within the constructed contact networks as compared to random networks of similar size and density. Using the generated contact networks, we evaluate several alternate vaccination policies and conclude that a simple policy that vaccinates the most mobile healthcare workers first, is robust and quite effective relative to a random vaccination policy. 相似文献
1000.
Rupali Chopra Shafat Ali Amit K. Srivastava Shweta Aggarwal Bhupender Kumar Siddharth Manvati Ponnusamy Kalaiarasan Mamta Jena Vijay K. Garg Sambit N. Bhattacharya Rameshwar N. K. Bamezai 《PLoS genetics》2013,9(7)
Leprosy is a chronic infectious disease caused by Mycobacterium Leprae, where the host genetic background plays an important role toward the disease pathogenesis. Various studies have identified a number of human genes in association with leprosy or its clinical forms. However, non-replication of results has hinted at the heterogeneity among associations between different population groups, which could be due to differently evolved LD structures and differential frequencies of SNPs within the studied regions of the genome. A need for systematic and saturated mapping of the associated regions with the disease is warranted to unravel the observed heterogeneity in different populations. Mapping of the PARK2 and PACRG gene regulatory region with 96 SNPs, with a resolution of 1 SNP per 1 Kb for PARK2 gene regulatory region in a North Indian population, showed an involvement of 11 SNPs in determining the susceptibility towards leprosy. The association was replicated in a geographically distinct and unrelated population from Orissa in eastern India. In vitro reporter assays revealed that the two significantly associated SNPs, located 63.8 kb upstream of PARK2 gene and represented in a single BIN of 8 SNPs, influenced the gene expression. A comparison of BINs between Indian and Vietnamese populations revealed differences in the BIN structures, explaining the heterogeneity and also the reason for non-replication of the associated genomic region in different populations. 相似文献