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111.
Reversible myocardial dysfunction: basics and evaluation 总被引:3,自引:0,他引:3
Large areas of non-functional but viable myocardium with reversible dysfunction are commonly seen in patients with acute myocardial infarction. Both reperfusion of acutely ischemic myocardium and chronic myocardial ischemia may produce a reversible forms of ventricular dysfunction. The two main conditions that lead to reversible myocardial dysfunction are stunned myocardium and hibernating myocardium. Myocardial stunning represents post-ischemic myocardial dysfunction that persists despite restoration of normal flow, with gradual return of contractile function. Hibernating myocardium is a state of persistently impaired myocardial function at rest due to reduced coronary blood flow owing to residual stenosis that can be restored toward normal by revascularization. The success of the revascularization procedures depends on the presence of amount of dysfunctional but viable myocardium. The basics and evaluation of reversible myocardial dysfunction are reviewed. 相似文献
112.
Upendra Kaul Ripen K Gupta Kottaram K Haridas Saligrama S Ramesh Kamal K Sethi Balbir Singh Rajiv Agarwal Ram D Yadave Tapan Ghose Rakesh R Sapra Rajiv Bajaj Madhukar Shahi Ajit Bhagwat Pramod Kumar Omen P Mathews Pratik K Soni 《Catheterization and cardiovascular interventions》2002,57(4):497-503
The results of primary coronary stenting for acute myocardial infarction (AMI) have been reported to improve significantly with the concomitant administration of platelet glycoprotein IIb/IIIa inhibitor abciximab. There are, however, no data available with the use of eptifibatide, a more cost-effective, small-molecule GP IIb/IIIa blocker with a shorter half-life. In a prospective multicenter feasibility and efficacy study, we assigned 55 consecutive patients with AMI being taken up for primary stenting to receive eptifibatide just before the procedure (two boluses of 180 microg/kg 10 min apart and a 24-hr infusion of 2 microg/kg/min). Clinical outcomes were evaluated at 30 days after the procedure. The angiographic patency of the vessel with TIMI flow rates, TIMI myocardial perfusion (TMP) grade, and corrected TIMI frame counts were assessed at the end of procedure and before hospital discharge. At 30 days, the primary endpoint, a composite of death, myocardial infarction, and urgent target vessel revascularization (TVR) was seen in 12.7% of patients. The TIMI 3 and TMP grade 3 flow, which was seen in 93% and 86% of patient, respectively, at the end of the procedure, declined to 86% and 78%, respectively (P < 0.05) before hospital discharge. Corrected TIMI frame counts also decreased from 25.7 +/- 7.2 to 22.9 +/- 6.8 (P < 0.05). There were five (9.1%) instances of subacute thrombosis (SAT) presenting as AMI, needing urgent TVR in all, within 3-5 days of the primary procedure. No excessive bleeding complication, directly attributable to the use of eptifibatide, was observed. The study was terminated prematurely because of an unacceptable SAT rate. Administration of eptifibatide along with primary stenting for AMI is associated with a high TIMI 3 and TMP grade 3 flow acutely. However, these flows decline significantly before hospital discharge and lead to a high rate of SAT. The dosage and duration of infusion of eptifibatide in this setting needs further evaluation. 相似文献
113.
Postoperative atrial fibrillation and mortality after coronary artery bypass surgery 总被引:4,自引:0,他引:4
Villareal RP Hariharan R Liu BC Kar B Lee VV Elayda M Lopez JA Rasekh A Wilson JM Massumi A 《Journal of the American College of Cardiology》2004,43(5):742-748
OBJECTIVES: We sought to determine if the occurrence of postoperative atrial fibrillation (AF) affects early or late mortality following coronary artery bypass surgery (CABG). BACKGROUND: Atrial fibrillation is the most common arrhythmia seen following CABG. METHODS: The Texas Heart Institute Cardiovascular Research Database was used to identify all patients that developed AF after isolated initial CABG from January 1993 to December 1999 (n = 994). This population was compared with patients who underwent CABG during the same period but did not develop AF (n = 5,481). In-hospital end points were adjusted using logistic regression models to account for baseline differences. Long-term survival was evaluated using a retrospective cohort design, where Cox proportional hazards methods were used to adjust for baseline differences, and with case-matched populations (n = 390, 195 per arm). RESULTS: Atrial fibrillation was diagnosed in 16% of the population. Postoperative AF was associated with greater in-hospital mortality (odds ratio [OR] 1.7, p = 0.0001), more strokes (OR 2.02, p = 0.001), prolonged hospital stays (14 vs. 10 days, p < 0.0001), and a reduced incidence of myocardial infarction (OR 0.62, p = 0.01). At four to five years, survival was worse in patients who developed postoperative AF (74% vs. 87%, p < 0.0001 in the retrospective cohort; 80% vs. 93%, p = 0.003 in the case-matched population). On multivariate analysis, postoperative AF was an independent predictor of long-term mortality (adjusted OR 1.5, p < 0.001 in the retrospective cohort; OR 3.4, p = 0.0018 in the case-matched population). CONCLUSIONS: The occurrence of AF following CABG identifies a subset of patients who have a reduced survival probability following CABG. The impact of various strategies, such as antiarrhythmics and warfarin, aimed at reducing AF and its complications deserves further study. 相似文献
114.
Is visfatin an adipokine or myokine? Evidence for greater visfatin expression in skeletal muscle than visceral fat in chickens 总被引:9,自引:0,他引:9
Krzysik-Walker SM Ocón-Grove OM Maddineni SR Hendricks GL Ramachandran R 《Endocrinology》2008,149(4):1543-1550
Visfatin, an adipokine hormone produced primarily by visceral adipose tissue in mammals, has been implicated in the immune system, cellular aging, and glucose metabolism. Increased visceral adiposity and hyperglycemia have been correlated with elevated plasma visfatin levels in humans. The present study investigated visfatin cDNA and protein expression as well as plasma visfatin levels in chickens that are selected for rapid growth and are naturally hyperglycemic relative to mammals. By RT-PCR, we detected visfatin cDNA in multiple tissues in the chicken. The deduced amino acid sequence of full-length chicken visfatin was 92-93% homologous to mammalian visfatin. Using real-time quantitative PCR and Western blotting, chicken skeletal muscle was found to contain 5- and 3-fold greater quantities of visfatin mRNA and protein than abdominal fat pad, respectively. Visfatin mRNA and protein quantities were not significantly different among sc and visceral adipose tissue depots. Skeletal muscle visfatin mRNA and protein quantities as well as plasma visfatin levels determined by enzyme immunoassay were significantly higher in 8-wk-old compared with 4-wk-old chickens, possibly due to rapid skeletal muscle growth and visceral fat accretion occurring in broiler chickens during this period. However, fasting and refeeding did not affect plasma visfatin levels in the chicken. Collectively, our results provide novel evidence that skeletal muscle, not the visceral adipose tissue, is the primary source of visfatin in chickens, thereby raising the possibility that visfatin may be acting as a myokine affecting skeletal muscle growth and metabolism. 相似文献
115.
Denny John Prabir Chatterjee Shruti Murthy Ramesh Bhat Baba Maiyaki Musa 《The Indian journal of tuberculosis》2018,65(3):208-217
Background
In India, multidrug-resistant tuberculosis (MDR-TB) patients are usually treated in hospitals. Decentralised care model, however, has been suggested as a possible alternative by the World Health Organization (WHO). In the “End TB Strategy”, the WHO highlights, as one of the key targets for 2035, that ‘no TB-affected families should face catastrophic hardship due to the tuberculosis’. Removal of financial barriers to health-care access and mitigation of catastrophic expenditures are therefore considered vital to achieve the universal health coverage (UHC) goal. Since forgoing healthcare due to the financial constraints is a known fact in India, decentralised care as an intervention choice (as against hospital-based care) might enhance equity provided it is an affordable choice. Thus, an economic evaluation was conducted, from the perspective of the national health system in India, to assess the cost-effectiveness of decentralised care compared to centralised care for MDR-TB.Methods
This study uses a decision-analytic model with a follow-up of two years to assess the expected costs of the decentralised versus the centralised approaches for MDR-TB treatment. A published systematic review of observational studies yielded the MDR-TB treatment outcomes, which included treatment success, treatment default, treatment failure, and mortality parameters. It was observed that these parameters did not vary significantly between the two alternatives. Treatment costs included the following costs: hospital admission costs, clinic costs, visits to laboratory and MDR-TB centre, drug therapy, injections and food. Costs data of drugs, diagnosis, hospital stay and travel to public facilities, based on a simple market survey, were taken from a recently published study on MDR-TB expenditures in the Chhattisgarh state of India. Potential cost savings related to the implementation of decentralised MDR-TB care for all patients who initiated MDR-TB treatment in India were additionally estimated.Results
Estimated average expected total treatment cost was US$ 3390.56 for the hospital-based model and US$ 1724.1 for the decentralised model for a patient treated for MDR-TB in India, generating potential savings of US$1666.50 per case, with ICER US$ 2382.68 per QALY gained. One of the primary drivers of this difference was the significantly more intensive (thus expensive) stay charges in the hospital. If the costs and treatment probabilities are extrapolated to the whole country, with 48114 MDR-TB patients initiated on treatment in 2017, decentralised care would have additional 1058 patients cured, gain additional 3824 QALYs, and avert 2165 deaths, as compared to centralised care, in India. At various scenarios of coverage rates of decentralised and centralised care the cost difference would range between 23% and 94% for the country.Conclusion
Our study provides evidence of cost savings for MDR-TB patients if patients choose decentralised treatment in comparison to suggested hospitalisation of these patients for centralised treatment with similar outcomes. The economic evaluation presented in this study expected significant efficiency gains in choice of two treatment options and the cost savings may improve equity. In India, treatment of MDR-TB using decentralised care is expected to result in similar patient outcomes at markedly reduced public health costs compared with centralised care. 相似文献116.
117.
Altered anxiety and weight gain in corticotropin-releasing hormone-binding protein-deficient mice 总被引:6,自引:0,他引:6 下载免费PDF全文
I. Jill Karolyi Heather L. Burrows Tennore M. Ramesh Masaharu Nakajima J. Shonee Lesh Eunju Seong Sally A. Camper Audrey F. Seasholtz 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(20):11595-11600
Corticotropin-releasing hormone (CRH) is widely recognized as the primary mediator of the neuroendocrine and behavioral responses to stress, including stress-induced anxiety. The biological activity of CRH and other mammalian CRH-like peptides, such as urocortin, may be modulated by CRH-binding protein (CRH-BP). To assess directly the CRH-BP function, we created a mouse model of CRH-BP deficiency by gene targeting. Basal adrenocorticotropic hormone and corticosterone levels are unchanged in the CRH-BP-deficient mice, and the animals demonstrate a normal increase in adrenocorticotropic hormone and corticosterone after restraint stress. In contrast, adult male CRH-BP-deficient mice show significantly reduced body weight when compared with wild-type controls. CRH-BP-deficient mice also exhibit a significant increase in anxiogenic-like behavior as assessed by the elevated plus maze and defensive withdrawal tests. The increased anorectic and anxiogenic-like behavior most likely is caused by increased "free" CRH and/or urocortin levels in the brain of CRH-BP-deficient animals, suggesting an important role for CRH-BP in maintaining appropriate levels of these peptides in the central nervous system. 相似文献
118.
119.
G. Ramalingam K. Venkata Saravanan T. Kayal Vizhi M. Rajkumar Kathirvelu Baskar 《RSC advances》2018,8(16):8516
Many synthesized semiconductor QDs materials are formed using trioctylphosphine oxide (TOPO) but it requires high temperature, is very expensive and is also hydrophobic. Our study deals with selective syntheses of CdSe and core–shell CdSe/ZnS quantum dots (QDs) in aqueous solution by a simple heating and refluxing method. It is more hydrophilic, needs less temperature, is economically viable and is eco-friendly. Bio-ligands, such as thioacetamide, itaconic acid and glutathione, were used as stabilizers for the biosynthesis of QDs. A simplified aqueous route was used to improve the quality of the colloidal nanocrystals. As a result, highly monodisperse, photoluminescent and biocompatible nanoparticles were obtained. The synthesized QDs were characterized by XRD, FTIR, confocal microscopy, ultraviolet (UV) absorption and photoluminescence (PL). The size of synthesized QDs was observed as 5.74 nm and the core–shell shape was confirmed by using XRD and confocal microscopy respectively. The QD nanoparticles showed antibacterial activity against pathogenic bacteria. The QDs could be applied for biological labelling, fluorescence bio-sensing and bio-imaging etc.Mystristic capped CdSe QDs with schematic diagram and formation mechanism of bio-taggable CdSe@ZnS QDs. 相似文献
120.
Inna Y. Gong Bandar Al-Amro G. V. Ramesh Prasad Philip W. Connelly Rachel M. Wald Ron Wald Djeven P. Deva Howard Leong-Poi Michelle M. Nash Weiqiu Yuan Lakshman Gunaratnam S. Joseph Kim Charmaine E. Lok Kim A. Connelly Andrew T. Yan 《Journal of cardiovascular magnetic resonance》2018,20(1):83