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991.
992.
Forman DE Chen AY Wiviott SD Wang TY Magid DJ Alexander KP 《The American journal of cardiology》2010,106(10):1382-1388
ST-segment elevation myocardial infarction (STEMI) is common in older adults and has high age-related mortality. We describe contemporary STEMI care using the National Cardiovascular Data Registry Acute Coronary Treatment and Intervention Network Registry-Get With The Guidelines (ACTION-GWTG) database. Patients with STEMI (n = 30,188) from 285 ACTION-GWTG sites from January 1, 2007 to June 30, 2008 were grouped by age (<75, 75 to 84, and ≥ 85 years) to compare baseline characteristics, reperfusion, and in-hospital outcomes. In this population, 79.7% (24,070) were <75 years old, 14.2% (4,273) were 75 to 84 years old, and 6.1% (1,845) were ≥ 85 years old (the oldest old). Compared to younger patients, the oldest-old patients (median age 88 years, interquartile range 86 to 91) were more often women, had more hypertension, and end-organ co-morbidity (heart failure and stroke, p <0.0001 for all). More than 42% of the oldest old were also cited as having contraindications to reperfusion, but with absolute or relative contraindications noted in only 10%, and patient preference was the most common reason indicated (45%). Even in reperfusion-eligible patients, the oldest old were less likely to receive it. Although patients who received reperfusion had better outcomes than those who did not, this was significant only for younger patients (< 75 years old, odds ratio 0.58, confidence interval 0.40 to 0.84). In conclusion, > 42% of the oldest old have reported contraindications to reperfusion, with neither mortality benefit nor harm in those who receive it. Disparities in process of care and co-morbidity may explain these observational findings. Whether efforts to optimize patient selection and initiate reperfusion therapy can improve outcomes in the oldest old with STEMI is unknown. 相似文献
993.
Robinson JS Featherstone D Vasanthapuram R Biggerstaff BJ Desai A Ramamurty N Chowdhury AH Sandhu HS Cavallaro KF Johnson BW 《The American journal of tropical medicine and hygiene》2010,83(5):1146-1155
We evaluated performance of three commercial Japanese encephalitis virus (JEV) IgM antibody capture enzyme-linked immunosorbent assay (MAC ELISA) kits with a panel of serological specimens collected during a surveillance project of acute encephalitis syndrome in India and acute meningitis and encephalitis syndrome in Bangladesh. The serum and cerebral spinal fluid specimens had been referred to the Centers for Disease Control and Prevention (CDC) for confirmatory testing. The CDC results and specimen classifications were considered the reference standard. All three commercial kits had high specificity (95-99.5%), but low sensitivities, ranging from 17-57%, with both serum and cerebrospinal fluid samples. Specific factors contributing to low sensitivity compared with the CDC ELISA could not be determined through further analysis of the limits and dilution end points of IgM detection. 相似文献
994.
ObjectiveHyperhomocysteinemia (HHcy) has been shown to impair the endothelial function of arterial vessels and promote thrombosis. There are no studies, however, assessing the effects of HHcy on the vasomotor function of venules. We hypothesized that HHcy activates pathophysiological mechanisms impairing flow/shear stress-dependent responses of venules.Methods and resultsChanges in diameter of isolated gracilis muscle venules (diameter: ~250 μm at 10 mmHg) of control and HHcy rats (induced by methionine diet for 5 weeks) to increases in intraluminal flow were measured. Increases in flow elicited dilations in control (at max.: 14 ± 1%), but induced constrictions in HHcy venules (at max.: ?24 ± 4%). Flow-induced constrictions in HHcy venules were converted to dilations in the presence of the thromboxane A2 (TxA2) receptor (TP) antagonist SQ 29,548, which were then abolished by the simultaneous administration of nitric oxide (NO) synthase inhibitor, L-NAME and non-selective cyclooxygenase (COX) blocker, indomethacin. In addition, the selective COX-2 inhibitor NS 398 reversed flow-induced constrictions to dilations, which were significantly decreased by additional COX-1 inhibitor, SC 560. Also, as compared to controls, a SOD/CAT sensitive increased ethidium bromide fluorescence was detected in HHcy small veins, indicating substantial production of reactive oxygen species (ROS) in HHcy. Correspondingly, SOD/CAT diminished flow-induced constrictions in venules of HHcy rats.ConclusionsIn hyperhomocysteinemia increases in flow/shear stress increases the production of COX-2-derived TxA2, and reactive oxygen species – that overcome the dilator effects of NO and prostaglandins – eliciting constrictions in skeletal muscle venules; changes which can increase vascular resistance and favor thrombus formation in the venular circulation. 相似文献
995.
Anand Srivastava Stéphane Gangnard Adam Round Sébastien Dechavanne Alexandre Juillerat Bertrand Raynal Grazyna Faure Bruno Baron Stéphanie Ramboarina Saurabh Kumar Singh Hassan Belrhali Patrick England Anita Lewit-Bentley Artur Scherf Graham A. Bentley Beno?t Gamain 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(11):4884-4889
Pregnancy-associated malaria (PAM) is a serious consequence of sequestration of Plasmodium falciparum-parasitized erythrocytes (PE) in the placenta through adhesion to chondroitin sulfate A (CSA) present on placental proteoglycans. Recent work implicates var2CSA, a member of the PfEMP1 family, as the mediator of placental sequestration and as a key target for PAM vaccine development. Var2CSA is a 350 kDa transmembrane protein, whose extracellular region includes six Duffy-binding-like (DBL) domains. Due to its size and high cysteine content, the full-length var2CSA extracellular region has not hitherto been expressed in heterologous systems, thus limiting investigations to individual recombinant domains. Here we report for the first time the expression of the full-length var2CSA extracellular region (domains DBL1X to DBL6ε) from the 3D7 parasite strain using the human embryonic kidney 293 cell line. We show that the recombinant extracellular var2CSA region is correctly folded and that, unlike the individual DBL domains, it binds with high affinity and specificity to CSA (KD = 61 nM) and efficiently inhibits PE from binding to CSA. Structural characterization by analytical ultracentrifugation and small-angle x-ray scattering reveals a compact organization of the full-length protein, most likely governed by specific interdomain interactions, rather than an extended structure. Collectively, these data suggest that a high-affinity, CSA-specific binding site is formed by the higher-order structure of the var2CSA extracellular region. These results have important consequences for the development of an effective vaccine and therapeutic inhibitors. 相似文献
996.
Sebastian L Desai A Madhusudana SN Ravi V 《International journal of antimicrobial agents》2009,33(2):168-173
Several investigations have shown that pentoxifylline possesses broad-spectrum antiviral activity against a range of RNA and DNA viruses. However, its ability to inhibit Japanese encephalitis virus (JEV) replication has not yet been studied. The present study was designed to investigate the antiviral activity of pentoxifylline against JEV in vitro and in vivo. The activity of pentoxifylline against JEV was evaluated in vitro using cytopathic effect inhibition and plaque reduction assays. Pentoxifylline was able to inhibit JEV replication in a dose-dependent manner at a 50% inhibitory concentration (IC(50)) of 50.3microg/mL (0.00018microM) and a therapeutic index (TI) of 10. Experiments to study the mechanism of antiviral action of pentoxifylline using in vitro translation of viral mRNA suggested that the drug did not interfere either with early or late protein synthesis but most likely exerted its action on virus assembly and/or release. Furthermore, the in vivo study showed that pentoxifylline at a concentration of 100mg/kg and 200mg/kg body weight was able to protect completely mice challenged with 50 x 50% lethal dose (LD(50)) of JEV. 相似文献
997.
Ram M. Meena Anita Garg Sangeeta Jadhav 《Bulletin of environmental contamination and toxicology》2009,82(5):586-589
Surface seawaters from the Dona Paula Bay, were collected at weekly intervals during March 2007 to March 2008, and analyzed
for butyltins (BT) such as tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT) using a GC–MS system. The mean concentrations
of TBT, DBT, MBT and total BT varied from <1–37, 4–19, 6–28 and 21–84 ng Sn L−1, respectively. Highest levels of BTs were recorded during May followed by April 2007 and March 2007 probably because the
shipping and tourism activities are very high during these months. 相似文献
998.
Anna María Nápoles Steven E. Gregorich Jasmine Santoyo-Olsson Helen O'Brien Anita L. Stewart 《Health services research》2009,44(4):1326-1344
Objective. Describe association of patient satisfaction with interpersonal processes of care (IPC) by race/ethnicity.
Data Sources/Study Setting. Interview with 1,664 patients (African Americans, English- and Spanish-speaking Latinos, and non-Latino Whites).
Study Design/Methods. Cross-sectional study of seven IPC measures (communication, patient-centered decision making, and interpersonal style) and three satisfaction measures (satisfaction with physicians, satisfaction with health care, and willingness to recommend physicians). Regression models explored associations, controlling for patient characteristics.
Principal Findings. In all groups: patient-centered decision making was positively associated with satisfaction with physicians ( B =0.10, p <.0001) and health care ( B =0.07, p <.001), and "recommend physicians" (OR=1.23, 95 percent CI 1.06, 1.43); discrimination was negatively associated with satisfaction with physicians ( B =0.09, p <.05) and health care ( B =0.17, p <.001). Unclear communication was associated with less satisfaction with physicians among Spanish-speaking Latinos. Explaining results was positively associated with all satisfaction outcomes for all groups with one exception (no association with satisfaction with physicians for Latino Spanish-speakers). Compassion/respect was positively associated with all outcomes for all groups with two exceptions (no association with satisfaction with health care among English-speaking Latinos and Whites).
Conclusions. All IPC measures were associated with at least one satisfaction outcome for all groups except for unclear communication. 相似文献
Data Sources/Study Setting. Interview with 1,664 patients (African Americans, English- and Spanish-speaking Latinos, and non-Latino Whites).
Study Design/Methods. Cross-sectional study of seven IPC measures (communication, patient-centered decision making, and interpersonal style) and three satisfaction measures (satisfaction with physicians, satisfaction with health care, and willingness to recommend physicians). Regression models explored associations, controlling for patient characteristics.
Principal Findings. In all groups: patient-centered decision making was positively associated with satisfaction with physicians ( B =0.10, p <.0001) and health care ( B =0.07, p <.001), and "recommend physicians" (OR=1.23, 95 percent CI 1.06, 1.43); discrimination was negatively associated with satisfaction with physicians ( B =0.09, p <.05) and health care ( B =0.17, p <.001). Unclear communication was associated with less satisfaction with physicians among Spanish-speaking Latinos. Explaining results was positively associated with all satisfaction outcomes for all groups with one exception (no association with satisfaction with physicians for Latino Spanish-speakers). Compassion/respect was positively associated with all outcomes for all groups with two exceptions (no association with satisfaction with health care among English-speaking Latinos and Whites).
Conclusions. All IPC measures were associated with at least one satisfaction outcome for all groups except for unclear communication. 相似文献
999.
1000.
Objectives To examine the association between state economic, political and health services capacity and state allocations for Title
V capacity for Children and Youth with Special Health Care Needs (CSHCN). Methods Numerous datasets were reviewed to select 13 state capacity measures: per capita Gross State Product (economic); governor’s
institutional powers and legislative professionalism (political); percent of Children with Special Health Care Needs, percent
of uninsured children, percent of children enrolled in Medicaid, state health funds as a percent of Gross State Product, ratio
of Medicaid to Medicare fees, percent of children in Medicaid enrolled in managed care, per capita Medicaid expenditures for
children, ratios of pediatricians/family practitioners and pediatric subspecialists per 10,000 children, and categorical versus
functional state definition of CSHCN (health). Five measures of Title V capacity were selected from the Title V Information
System, four that reflect allocation decisions by states and the fifth a state assessment of the role of families in Title
V decision-making: ratio of state/federal Title V spending; per capita state Title V spending; percent of state Title V spending
on CSHCN; state per child spending on CSHCN; and, state Title V Family Participation Score. OLS regression was used to model
the association between state and Title V capacity measures. Results The percentage of the state’s gross state product (GSP) accounted for by state health funds and the per capita GSP were positively
associated with the per capita expenditures on all children. The percentage of CSHCN in the state was negatively associated
with the ratio of state to federal support for Title V and the per child expenditures on CSHCN. Lower family participation
scores were associated with having a hybrid legislature; however, higher family participation scores were found in states
using a functional definition of special needs. Conclusions Measures of state economic, political and health services capacity do not demonstrate consistent and significant associations
with the Title V capacity measures that we explored. States with greater economic capacity appear to devote more financial
resources to Title V. Our finding that per capita CSHCN expenditures are negatively associated with the percentage of CSHCN
in the state suggests that there is an upper limit on what states devote to CSHCN. Our current understanding of what state
factors influence Title V capacity remains limited. 相似文献