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81.
McQueen AP Zhang D Hu P Swenson L Yang Y Zaha VG Hoffman JL Yun UJ Chakrabarti G Wang Z Albertine KH Abel ED Litwin SE 《Journal of molecular and cellular cardiology》2005,39(6):882-892
Diabetics have worse outcomes than nondiabetics after a variety of cardiac insults. We tested the hypothesis that impaired insulin receptor signaling in myocytes worsens cardiac remodeling and function following injury, even in the absence of hyperglycemia. Mice with cardiomyocyte-restricted knock out of the insulin receptor (CIRKO) and wild type (WT) mice were treated with isoproterenol (ISO) for 2 or 5 days. Heart rates and cardiac mass increased comparably following ISO in WT and CIRKO mice. After 5 days, WT hearts were hyperdynamic by echocardiographic and left ventricular pressure measurements. However, CIRKO hearts had a blunted increase in contractility and relaxation following ISO. Interestingly, single myocytes isolated from both CIRKO ISO and WT ISO hearts had increased cellular shortening with prolonged time to peak shortening vs. respective shams. Thus, loss of myocytes or extramyocyte factors, rather than intrinsic dysfunction of surviving myocytes, caused the blunted inotropic response in ISO treated CIRKO hearts. Indeed, CIRKO ISO mice had increased troponin release after 2 days and greater interstitial and sub-endocardial fibrosis at 5 days than did ISO WT. Apoptosis assessed by TUNEL and caspase staining was increased in CIRKO ISO compared to WT ISO hearts; however, very few of the apoptotic nuclei were clearly in cardiac myocytes. After 5 days of ISO treatment, VEGF expression was increased in WT but not in CIRKO hearts. In keeping with this finding, capillary density was reduced in CIRKO ISO relative to WT ISO. Basal expression of hypoxia-inducible factor-1alpha was lower in CIRKO vs. WT hearts and may explain the blunted VEGF response. Thus, absence of insulin receptor signaling in the cardiac myocyte worsens catecholamine-mediated myocardial injury, at least in part, via mechanisms that tend to impair myocardial blood flow and increase ischemic injury. 相似文献
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Daniel Quan Lucía Luna Wong Anita Shallal Raghav Madan Abel Hamdan Heaveen Ahdi Amir Daneshvar Manasi Mahajan Mohamed Nasereldin Meredith Van Harn Ijeoma Nnodim Opara Marcus Zervos 《Journal of general internal medicine》2021,36(5):1302
BackgroundThe impact of race and socioeconomic status on clinical outcomes has not been quantified in patients hospitalized with coronavirus disease 2019 (COVID-19).ObjectiveTo evaluate the association between patient sociodemographics and neighborhood disadvantage with frequencies of death, invasive mechanical ventilation (IMV), and intensive care unit (ICU) admission in patients hospitalized with COVID-19.DesignRetrospective cohort study.SettingFour hospitals in an integrated health system serving southeast Michigan.ParticipantsAdult patients admitted to the hospital with a COVID-19 diagnosis confirmed by polymerase chain reaction.Main MeasuresPatient sociodemographics, comorbidities, and clinical outcomes were collected. Neighborhood socioeconomic variables were obtained at the census tract level from the 2018 American Community Survey. Relationships between neighborhood median income and clinical outcomes were evaluated using multivariate logistic regression models, controlling for patient age, sex, race, Charlson Comorbidity Index, obesity, smoking status, and living environment.Key ResultsBlack patients lived in significantly poorer neighborhoods than White patients (median income: $34,758 (24,531–56,095) vs. $63,317 (49,850–85,776), p < 0.001) and were more likely to have Medicaid insurance (19.4% vs. 11.2%, p < 0.001). Patients from neighborhoods with lower median income were significantly more likely to require IMV (lowest quartile: 25.4%, highest quartile: 16.0%, p < 0.001) and ICU admission (35.2%, 19.9%, p < 0.001). After adjusting for age, sex, race, and comorbidities, higher neighborhood income ($10,000 increase) remained a significant negative predictor for IMV (OR: 0.95 (95% CI 0.91, 0.99), p = 0.02) and ICU admission (OR: 0.92 (95% CI 0.89, 0.96), p < 0.001).ConclusionsNeighborhood disadvantage, which is closely associated with race, is a predictor of poor clinical outcomes in COVID-19. Measures of neighborhood disadvantage should be used to inform policies that aim to reduce COVID-19 disparities in the Black community.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-020-06527-1.KEY WORDS: COVID-19, disparities, disadvantage, socioeconomic status, race 相似文献
84.
Chigozie Jesse Uneke Abel Ebeh Ezeoha Henry Uro-Chukwu Chinonyelum Thecla Ezeonu Ogbonnaya Ogbu Friday Onwe Chima Edoga 《Online Journal of Public Health Informatics》2015,7(2)
Background
In Nigeria, one of the major challenges associated with evidence-to-policy link in the control of infectious diseases of poverty (IDP), is deficient information literacy knowledge and skill among policymakers. There is need for policymakers to acquire the skill to discover relevant information, accurately evaluate retrieved information and to apply it correctly.Objectives
To use information literacy tool of International Network for Availability of Scientific Publications (INASP) to enhance policymakers'' knowledge and skill for policymaking on control of IDP in Nigeria.Methods
Modified "before and after" intervention study design was used in which outcomes were measured on target participants both before the intervention is implemented and after. This study was conducted in Ebonyi State, south-eastern Nigeria and participants were career health policy makers. A two-day health-policy information literacy training workshop was organized to enhance participants" information literacy capacity. Topics covered included: introduction to information literacy; defining information problem; searching for information online; evaluating information; science information; knowledge sharing interviews; and training skills.Results
A total of 52 policymakers attended the workshop. The pre-workshop mean rating (MNR) of knowledge and capacity for information literacy ranged from 2.15-2.97, while the post-workshop MNR ranged from 3.34-3.64 on 4-point scale. The percentage increase in MNR of knowledge and capacity at the end of the workshop ranged from 22.6%-55.3%.Conclusion
The results of this study suggest that through information literacy training workshop policy makers can acquire the knowledge and skill to identify, capture and share the right kind of information in the right contexts to influence relevant action or a policy decision. 相似文献85.
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87.
Miller MA Croft LB Belanger AR Romero-Corral A Somers VK Roberts AJ Goldman ME 《The American journal of cardiology》2008,101(9):1281-1284
The National Institute of Occupational Safety and Health mortality study of National Football League (NFL) players concluded that retired NFL linemen have an increased risk of cardiovascular death compared with both nonlinemen and the general population. Though elevated body mass index contributed to the increased cardiac risk of linemen, it could not fully account for the mortality observed, suggesting that other unmeasured cardiovascular risk factors were involved. We performed a cross-sectional prevalence study of metabolic syndrome (MS), and its individual component criteria, in 510 retired NFL players who were recruited to multicity health screenings from February 2004 through June 2006. The International Diabetes Federation criteria were used to define MS. The MS component criteria of body mass index>30 kg/m2, reduced high-density lipoprotein, and raised fasting glucose were more prevalent in linemen compared with nonlinemen (85.4% vs 50.3%, p<0.001; 42.1% vs 32.7%, p=0.04; 60.4% vs 37.6%, p<0.001, respectively). Metabolic syndrome was more prevalent in linemen compared with nonlinemen (59.8% vs 30.1%, p<0.001). In conclusion, linemen exhibited a high prevalence of MS, almost double the prevalence of their nonlinemen counterparts. These findings may partially explain the increased risk for cardiovascular death observed in retired linemen and could have significant public health implications for preprofessional training regimens and postprofessional health maintenance. 相似文献
88.
Cardiovascular risk after bariatric surgery for obesity 总被引:1,自引:0,他引:1
Batsis JA Sarr MG Collazo-Clavell ML Thomas RJ Romero-Corral A Somers VK Lopez-Jimenez F 《The American journal of cardiology》2008,102(7):930-937
Obese patients have an increased prevalence of cardiovascular (CV) risk factors, which improve with bariatric surgery, but whether bariatric surgery reduces long-term CV events remains ill defined. A systematic review of published research was conducted, and CV risk models were applied in a validation cohort previously published. A standardized MEDLINE search using terms associated with obesity, bariatric surgery, and CV risk factors identified 6 test studies. The validation cohort consisted of a population-based, historical cohort of 197 patients who underwent Roux-en-Y gastric bypass and 163 control patients, identified through the Rochester Epidemiology Project. Framingham and Prospective Cardiovascular Munster Heart Study (PROCAM) risk scores were applied to calculate 10-year CV risk. In the validation cohort, absolute 10-year Framingham risk score for CV events was lower at follow-up in the bariatric surgery group (7.0% to 3.5%, p <0.001) compared with controls (7.1% to 6.5%, p = 0.13), with an intergroup absolute difference in risk reduction of 3% (p <0.001). PROCAM risk in the bariatric surgery group decreased from 4.1% to 2.0% (p <0.001), whereas the control group exhibited only a modest decrease (4.4% to 3.8%, p = 0.08). Using mean data from the validation study, the trend and directionality in risk was similar in the Roux-en-Y group. The test studies confirmed the directionality of CV risk, with estimated relative risk reductions for bariatric surgery patients ranging from 18% to 79% using the Framingham risk score compared with 8% to 62% using the PROCAM risk score. In conclusion, bariatric surgery predicts long-term decreases in CV risk in obese patients. 相似文献
89.
90.
Daxing Gao Michael J. Ciancanelli Peng Zhang Oliver Harschnitz Vincent Bondet Mary Hasek Jie Chen Xin Mu Yuval Itan Aurlie Cobat Vanessa Sancho-Shimizu Benedetta Bigio Lazaro Lorenzo Gabriele Ciceri Jessica McAlpine Esperanza Anguiano Emmanuelle Jouanguy Damien Chaussabel Isabelle Meyts Michael S. Diamond Laurent Abel Sun Hur Gregory A. Smith Luigi Notarangelo Darragh Duffy Lorenz Studer Jean-Laurent Casanova Shen-Ying Zhang 《The Journal of clinical investigation》2021,131(1)
Human herpes simplex virus 1 (HSV-1) encephalitis can be caused by inborn errors of the TLR3 pathway, resulting in impairment of CNS cell-intrinsic antiviral immunity. Deficiencies of the TLR3 pathway impair cell-intrinsic immunity to vesicular stomatitis virus (VSV) and HSV-1 in fibroblasts, and to HSV-1 in cortical but not trigeminal neurons. The underlying molecular mechanism is thought to involve impaired IFN-α/β induction by the TLR3 recognition of dsRNA viral intermediates or by-products. However, we show here that human TLR3 controls constitutive levels of IFNB mRNA and secreted bioactive IFN-β protein, and thereby also controls constitutive mRNA levels for IFN-stimulated genes (ISGs) in fibroblasts. Tlr3–/– mouse embryonic fibroblasts also have lower basal ISG levels. Moreover, human TLR3 controls basal levels of IFN-β secretion and ISG mRNA in induced pluripotent stem cell–derived cortical neurons. Consistently, TLR3-deficient human fibroblasts and cortical neurons are vulnerable not only to both VSV and HSV-1, but also to several other families of viruses. The mechanism by which TLR3 restricts viral growth in human fibroblasts and cortical neurons in vitro and, by inference, by which the human CNS prevents infection by HSV-1 in vivo, is therefore based on the control of early viral infection by basal IFN-β immunity. 相似文献