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81.
Madhavan SR Reddy S Panuganti PK Joshi R Mallidi J Raju K Raju KR Iyengar S Reddy KS Patel A Neal B Calambur N Tandri H 《Indian pacing and electrophysiology journal》2011,11(4):93-102
Background
Sudden cardiac death (SCD) is a common initial presentation of coronary artery disease (CAD). Despite the growing epidemic of CAD in India, the epidemiology of SCD is largely unknown.Objective
The objective of the study was to define the prevalence and determinants of sudden cardiac deaths in rural South India.Methods
Prospective mortality surveillance was conducted in 45 villages (180,162 subjects) in rural South India between January 2006 and October 2007. Trained multipurpose health workers sought to do verbal autopsies within 4 weeks of any death. Detailed questionnaires including comorbidities and circumstances surrounding death were recorded. SCD was adjudicated using the modified Hinkle-Thaler classification.Results
A total of 1916 deaths occurred in the study population over the 22 month time period and verbal autopsy was obtained in 1827 (95%) subjects. Overall mean age of the deceased was 62 ± 20 years and 1007 (55%) were men. Cardiovascular and cerebrovascular diseases together accounted for 559 deaths (31%), followed by infectious disease (163 deaths, 9%), cancer (126 deaths, 7%) and suicide (93 deaths, 5%).Of the 1827 deaths, after excluding accidental deaths (89 deaths), 309 deaths (17%) met criteria for SCD. Cardiovascular disease was the underlying causes in the majority of the SCD events (231/309 (75%)). On multivariate analyses, previous MI/CAD (p < 0.001, OR 14.25), hypertension (p < 0.001, OR 1.84), and age groups between 40-60 yrs (p=0.029) were significantly associated with SCD.Conclusion
Sudden cardiac death accounted for up to half of the cardiovascular deaths in rural Southern India. Traditional cardiovascular risk factors were strongly associated with SCD. 相似文献82.
Iyengar A Gilbert T Woodfine T Knowles JM Diniz FM Brenneman RA Louis EE Maclean N 《Molecular ecology》2007,16(12):2436-2449
Scimitar-horned oryx, now considered extinct in the wild, persists in large numbers in captivity. In this first molecular genetic study on this species, we explore the patterns of genetic diversity across European, North American, and a few other captive groups using microsatellite markers and mitochondrial control region sequencing. Strong population structure was not evident from microsatellite data but we discovered deep divergence within the mitochondrial DNA haplotypes from a network analysis where three disconnected networks were obtained, with estimated divergence times of c. 2.1-2.7 million years. Mismatch distribution analyses suggest population expansions c. 1.2 and 0.5 million years ago. We discuss our findings in the context of historical climatic changes in North Africa and use information obtained on current patterns of genetic diversity within captive groups to make recommendations for future captive management and reintroduction strategies. 相似文献
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Pajvani UB Trujillo ME Combs TP Iyengar P Jelicks L Roth KA Kitsis RN Scherer PE 《Nature medicine》2005,11(7):797-803
We describe the generation and characterization of the first inducible 'fatless' model system, the FAT-ATTAC mouse (fat apoptosis through targeted activation of caspase 8). This transgenic mouse develops identically to wild-type littermates. Apoptosis of adipocytes can be induced at any developmental stage by administration of a FK1012 analog leading to the dimerization of a membrane-bound, adipocyte-specific caspase 8-FKBP fusion protein. Within 2 weeks of dimerizer administration, FAT-ATTAC mice show near-knockout levels of circulating adipokines and markedly reduced levels of adipose tissue. FAT-ATTAC mice are glucose intolerant, have diminished basal and endotoxin-stimulated systemic inflammation, are less responsive to glucose-stimulated insulin secretion and show increased food intake independent of the effects of leptin. Most importantly, we show that functional adipocytes can be recovered upon cessation of treatment, allowing the study of adipogenesis in vivo, as well as a detailed examination of the importance of the adipocyte in the regulation of multiple physiological functions and pathological states. 相似文献
86.
Iyengar A Babu VN Hedges S Venkataraman AB Maclean N Morin PA 《Molecular ecology》2005,14(8):2281-2297
The Asiatic wild dog or dhole was once very widely distributed across Asia but now has a very fragmented range. In this first genetic study of this little-known species, we obtained information on genetic diversity, phylogeography, and social structure using both mitochondrial control region sequencing and microsatellite genotyping of noninvasive faecal samples from wild populations, as well as from museum and captive samples. A pattern largely consistent with isolation by distance across the Asian mainland was observed, with no clear subspecies distinctions. However, two major phylogeographical groupings were found across the mainland, one extending from South, Central, and North India (south of the Ganges) into Myanmar, and the other extending from India north of the Ganges into northeastern India, Myanmar, Thailand and the Malaysian Peninsula. We propose a scenario involving glaciation events that could explain this pattern. The origin of the dhole populations in Sumatra and Java is enigmatic and requires further study. Very low levels of genetic diversity were observed among wild dholes from Baluran National Park in Java, Indonesia, but in contrast, high levels were observed in Mudumalai Wildlife Sanctuary in South India. 相似文献
87.
Effects of glucagon and guanyl nucleotides on the rat liver plasma membrane adenylyl cyclase were studied. It was established that: 1) glucagon stimulates the fully guanyl-5'-yl imidodiphosphate (GMP-P(NH)P)-activated enzyme between 20 and 70%, provided a guanyl nucleotide is present in the assay; 2) glucagon has no effect on adenylyl cyclase activity in membranes activated fully by GMP-P(NH)P and then washed free of nucleotides. It is concluded that occupancy of the guanyl nucleotide binding site that activates the catalytic moiety of the system is not sufficient to promote hormone-receptor coupling to adenylyl cyclase and that occupancy of a second site by guanyl nucleotides is essential to effect stimulation of adenylyl cyclase by the glucagon-receptor complex. The data presented raise the question whether the guanyl nucleotide site that promotes coupling is distinct from the guanyl nucleotide site that modulates binding of glucagon to receptor and whether the occupancy of the guanyl nucleotide site associated with the catalytic moiety is necessary for coupling. 相似文献
88.
Jose A. Martinez-Perez Smriti Iyengar Harlan E. Shannon David Bleakman Andrew Alt David K. Clawson Brian M. Arnold Michael G. Bell Thomas J. Bleisch Ana M. Castaño Miriam Del Prado Esteban Dominguez Ana M. Escribano Sandra A. Filla Ken H. Ho Kevin J. Hudziak Carrie K. Jones Ana Mateo Paul L. Ornstein 《Bioorganic & medicinal chemistry letters》2013,23(23):6463-6466
We have explored the decahydroisoquinoline scaffold, bearing a phenyl tetrazole, as GluK1 antagonists with potential as oral analgesics. We have established the optimal linker atom between decahydroisoquinoline and phenyl rings and demonstrated an improvement of both the affinity for the GluK1 receptor and the selectivity against the related GluA2 receptor with proper phenyl substitution. In this Letter, we also disclose in vivo data that led to the discovery of LY545694·HCl, a compound with oral efficacy in two persistent pain models. 相似文献
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90.
The present work demonstrates the utility of the functionalized carbon nanotubes, poly(4-aminobenzene sulfonic acid) (PABS) grafted multiwalled carbon nanotubes, MWNT-g-PABS, as an electrode modifier towards achieving ultrasensitive detection of a model drug, sildenafil citrate (SC). PABS units in MWNT-g-PABS interact with SC, pre-concentrate and accumulate at the surface. The electron transduction from SC to electrode is augmented via MWNT-g-PABS. As a result, the MWNT-g-PABS modified electrode exhibited ultrasensitive (57.7 μA/nM) and selective detection of SC with a detection limit of 4.7 pM. The present work provides scope towards targeting ultrasensitivity for the detection of biomolecules/drug through rational design and incorporation of appropriate chemical components to carbon nanotubes. 相似文献