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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
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Aluminium oxide nanoparticles induced morphological changes,cytotoxicity and oxidative stress in Chinook salmon (CHSE‐214) cells
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Koigoora Srikanth Amit Mahajan Eduarda Pereira Armando Costa Duarte Janapala Venkateswara Rao 《Journal of applied toxicology : JAT》2015,35(10):1133-1140
Aluminium oxide nanoparticles (Al2O3 NPs) are increasingly used in diverse applications that has raised concern about their safety. Recent studies suggested that Al2O3 NPs induced oxidative stress may be the cause of toxicity in algae, Ceriodaphnia dubia, Caenorhabditis elegans and Danio rerio. However, there is paucity on the toxicity of Al2O3 NPs on fish cell lines. The current study was aimed to investigate Al2O3 NPs induced cytotoxicity, oxidative stress and morphological abnormality of Chinnok salmon cells (CHSE‐214). A dose‐dependent decline in cell viability was observed in CHSE‐214 cells exposed to Al2O3 NPs. Oxidative stress induced by Al2O3 NPs in CHSE‐214 cells has resulted in the significant reduction of superoxide dismutase, catalase and glutathione in a dose‐dependent manner. However, a significant increase in glutathione sulfo‐transferase and lipid peroxidation was observed in CHSE‐214 cells exposed to Al2O3 NPs in a dose‐dependent manner. Significant morphological changes in CHSE‐214 cells were observed when exposed to Al2O3 NPs at 6, 12 and 24 h. The cells started to detach and appear spherical at 6 h followed by loss of cellular contents resulting in the shrinking of the cells. At 24 h, the cells started to disintegrate and resulted in cell death. Our data demonstrate that Al2O3 NPs induce cytotoxicity and oxidative stress in a dose‐dependent manner in CHSE‐214 cells. Thus, our current work may serve as a base‐line study for future evaluation of toxicity studies using CHSE‐214 cells. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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George M. Varghese Jeshina Janardhanan Sanjay K. Mahajan David Tariang Paul Trowbridge John A.J. Prakash Thambu David Sowmya Sathendra O.C. Abraham 《Emerging infectious diseases》2015,21(1):64-69
Scrub typhus, an acute febrile illness that is widespread in the Asia-Pacific region, is caused by the bacterium Orientia tsutsugamushi, which displays high levels of antigenic variation. We conducted an investigation to identify the circulating genotypes of O. tsutsugamushi in 3 scrub typhus–endemic geographic regions of India: South India, Northern India, and Northeast India. Eschar samples collected during September 2010–August 2012 from patients with scrub typhus were subjected to 56-kDa type-specific PCR and sequencing to identify their genotypes. Kato-like strains predominated (61.5%), especially in the South and Northeast, followed by Karp-like strains (27.7%) and Gilliam and Ikeda strains (2.3% each). Neimeng-65 genotype strains were also observed in the Northeast. Clarifying the genotypic diversity of O. tsutsugamushi in India enhances knowledge of the regional diversity among circulating strains and provides potential resources for future region-specific diagnostic studies and vaccine development. 相似文献
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D K Mahajan G Anderson W K Poole R B Billiar B Little 《The Journal of clinical endocrinology and metabolism》1983,57(3):585-591
To study whether an alteration of placental steroid metabolism occurs during human pregnancy similar to that in the ewe, we measured the concentration of 17 alpha,20 alpha-dihydroxypregn-4-en-3-one (17,20 alpha-OHP) in peripheral plasma. As the pregnant ewe nears term, the utero-ovarian venous concentrations of 17,20 alpha-OHP increase, suggesting induction of placental 17 alpha-hydroxylase. The mean plasma concentration of 17,20 alpha-OHP measured by RIA in normal menstruating women was 1.1 +/- 0.12 (+/- SE) ng/ml. Similar values were found in plasma from ovariectomized women. In the first and second trimesters of pregnancy, the plasma values of 17,20 alpha-OHP were not significantly different from those in the nonpregnant women, while in the third trimester, the mean plasma concentration was significantly increased (mean +/- SE, 2.6 +/- 0.3 ng/ml). The plasma concentration of 17,20 alpha-OHP was studied in 15 women in late pregnancy, during labor, at delivery, and postpartum. The concentration increased during labor as delivery approached and reached a maximum at the time of delivery, ranging from 4.1-11.2 ng/ml, followed by a significant decrease within 1-4 h postpartum. The mean (+/- SE) 17,20 alpha-OHP concentrations in the venous and arterial cord blood were 8.7 +/- 1.6 and 5.8 +/- 2.0 ng/ml, respectively. To study the effect of increased circulating level of corticosteroids on the serum concentration of progestins, 74 women with premature labor with or without premature rupture of membranes were treated with either placebo or 4 im injections of dexamethasone phosphate (5 mg each) at 12-h intervals. Blood samples were drawn at 0, 14, 26, and 46 h, approximately 2 h after each dexamethasone dose. Plasma progesterone, 17 alpha-hydroxyprogesterone (17-OHP), and 17,20 alpha-OHP values at zero time were 140 +/- 15.8 (+/- SE; n = 21), 7.8 +/- 1.5 ng/ml (n = 16), and 2.3 +/- 0.3 ng/ml (n = 20), respectively. In patients treated with dexamethasone, the plasma progesterone values tended to increase at 14, 20, and 46 h, but 17-OHP and 17,20 alpha-OHP values decreased significantly compared to levels in placebo-treated patients. In conclusion, the concentration of plasma 17,20 alpha-OHP increased during the third trimester of pregnancy, and the increment continued through labor and delivery. During antenatal dexamethasone administration, progesterone in the maternal circulation tended to increase, while 17-OHP and 17,20 alpha-OHP decreased significantly. In the human, in contrast to the ewe, dexamethasone treatment in the third trimester does not appear to stimulate placental 17 alpha-hydroxylase activity. 相似文献
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Aims/hypothesis Insulin has nitric-oxide-dependent vasodilatory effects in muscle, including capillary recruitment, that enhance access for itself and glucose. However, nitric-oxide-dependent vasodilators other than methacholine do not enhance insulin action. Our hypothesis is that methacholine, unlike bradykinin, enhances insulin-mediated glucose uptake in muscle by augmenting capillary recruitment.Methods Local infusion of either methacholine or bradykinin into one leg of the anaesthetised rat was made during physiological insulin (3 mU·kg–1·min–1) infusion under euglycaemic conditions and without affecting systemic blood pressure. Whole-body glucose infusion was determined, as was femoral blood flow, 2-deoxyglucose uptake into calf muscles and the metabolism of infused 1-methylxanthine, a measure of capillary recruitment for each leg.Results Methacholine alone (0.3 µmol·l–1) increased femoral arterial blood flow, increased capillary recruitment but had no effect on 2-deoxyglucose uptake of the test leg relative to the contra-lateral control leg. Insulin alone (systemically) required a glucose infusion rate of 8.7 mg·kg–1·min–1 to maintain euglycaemia, increased 2-deoxyglucose uptake and capillary recruitment, but was without effect on femoral blood flow in either leg. Local methacholine with systemic insulin infusion increased femoral blood flow, 2-deoxyglucose uptake and capillary recruitment in the test leg only. Bradykinin (0.07 µmol·l–1), alone or with insulin, administered in a manner that increased femoral blood flow similarly to methacholine, did not affect 2-deoxyglucose uptake or capillary recruitment.Conclusions/interpretation Methacholine but not bradykinin enhances insulin-mediated muscle glucose uptake in vivo. We conclude that methacholine acts at specific sites in the vasculature of muscle to stimulate capillary recruitment and thereby enhance insulin access. 相似文献
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BACKGROUND AND OBJECTIVES: The aim of this study was to demonstrate the efficiency of diverting the initial 20-ml donation from the collection bag and of an improved donor-arm disinfection procedure in reducing bacterial contamination in blood. MATERIALS AND METHODS: Donations were collected in bags specially manufactured for the study. These bags incorporated two satellite pouches into each of which 20 ml of blood was collected. Blood initially flowed into sample pouch P1, representing a diversion pouch. Pouch P2 was then filled with 20 ml of blood, which allowed us to sample the collection bag after diversion was complete. Blood then flowed into the standard collection bag. The contents of the pouches were aerobically and anaerobically cultured on the BacT/ALERT automated culture system for 7 days. Two procedures were investigated in the study (each involving 1409 blood donations): one analysed the current disinfection procedure; and the other analysed an improved donor-arm disinfection procedure. RESULTS: The use of diversion alone resulted in a 47% reduction in contamination, and improved donor-arm disinfection alone resulted in a 57% reduction in contamination. Diversion plus improved donor-arm disinfection produced a predicted 77% reduction in contamination. CONCLUSIONS: The study validates diversion and an improved donor-arm disinfection procedure. In combination, these two interventions produced a substantial reduction in contamination. These procedures are to be introduced by the English National Blood Service to enhance the safety of the blood supply. 相似文献