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91.
Deformable sickle erythrocytes have been reported by Mohandas and Evans to be more adherent to vascular endothelium than rigid irreversibly sickled cells (ISC). To define the clinical implications of this finding we have determined genetic, hematological, clinical, and rheological characteristics of sickle erythrocytes obtained from 65 patients with sickle cell anemia and fetal hemoglobin (Hb F) levels less than 15%. The alpha-globin gene number had a significant effect on the hematological parameters, the percentage of dense cells, ISC number, and HB A2 levels. The presence or absence of alpha thalassemia, however, had no effect on the frequency and severity of the sickle cell painful crisis (r = 0.06, P greater than .05). RBC deformability, determined by an ektacytometer, showed great heterogeneity among patients with three or four alpha-globin genes. Linear regression analyses of the data showed significant positive correlation of the frequency and severity of the painful crisis with RBC deformability (r = 0.49, P less than .001), and negative correlations with the percentage of dense cells (r = -0.37, P = .002), and the percentage of ISC (r = -0.46, P less than .001). We propose that the more deformable the sickle RBC are, the greater their adherence to vascular endothelium, and the more they cause vaso-occlusive crises, RBC deformability and the percentage of dense cells (or ISC) seem to have a predictive value of the frequency and severity of painful crises in sickle cell anemia. 相似文献
92.
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
93.
Deeg HJ; Storb R; Thomas ED; Flournoy N; Kennedy MS; Banaji M; Appelbaum FR; Bensinger WI; Buckner CD; Clift RA 《Blood》1985,65(6):1325-1334
Seventy-five patients, 13 to 49 years of age, with acute nonlymphoblastic leukemia in first remission were treated with cyclophosphamide, fractionated total body irradiation, and marrow transplantation from an HLA-identical sibling and randomized to receive either cyclosporine (CSP) (n = 36) or methotrexate (MTX) (n = 39) as prophylaxis for graft-v-host disease (GVHD). All patients engrafted, and 22 who were given CSP and 21 who were given MTX, are alive at 20 to 47 (median, 35) months (P = .5). Engraftment as assessed by granulocyte recovery (P less than .0005) and platelet transfusion requirement (P = .01) was faster in patients on CSP. Twelve patients (33%) on CSP and 22 (56%) on MTX developed acute GVHD of grades II through IV (P = .07) and 15 of 30 on CSP and 14 of 32 on MTX that were at risk developed chronic GVHD. The most frequent causes of death were interstitial pneumonitis and marrow relapse of leukemia, which occurred with similar frequency in both groups. Beneficial effects observed in patients on CSP included less severe mucositis and shorter duration of hospitalization; adverse effects included renal function impairment and hypertension. These data confirm that CSP is a useful immunosuppressant in patients undergoing marrow transplantation but fail to show a significant improvement in survival as compared with the standard regimen of MTX. 相似文献
94.
95.
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
96.
Marrow transplantation with or without donor buffy coat cells for 65 transfused aplastic anemia patients 总被引:4,自引:3,他引:4
Storb R; Doney KC; Thomas ED; Appelbaum F; Buckner CD; Clift RA; Deeg HJ; Goodell BW; Hackman R; Hansen JA; Sanders J; Sullivan K; Weiden PL; Witherspoon RP 《Blood》1982,59(2):236-246
Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%). 相似文献
97.
Sustained, retransplantable, multilineage engraftment of highly purified adult human bone marrow stem cells in vivo 总被引:4,自引:8,他引:4
Civin CI; Almeida-Porada G; Lee MJ; Olweus J; Terstappen LW; Zanjani ED 《Blood》1996,88(11):4102-4109
Data from many laboratory and clinical investigations indicate that CD34+ cells comprise approximately 1% of human bone marrow (BM) mononuclear cells, including the progenitor cells of all the lymphohematopoietic lineages and lymphohematopoietic stem cells (stem cells). Because stem cells are an important but rare cell type in the CD34+ cell population, investigators have subdivided the CD34+ cell population to further enrich stem cells. The CD34+/CD38- cell subset comprises less than 10% of human CD34+ adult BM cells (equivalent to < 0.1% of marrow mononuclear cells), lacks lineage (lin) antigens, contains cells with in vitro replating capacity, and is predicted to be highly enriched for stem cells. The present investigation tested whether the CD34+/CD38- subset of adult human marrow generates human hematopoiesis after transfer to preimmune fetal sheep. CD34+/ CD38- cells purified from marrow using immunomagnetic microspheres or fluorescence-activated cell sorting generated easily detectable, long- term, multilineage human hematopoiesis in the human-fetal sheep in vivo model. In contrast, transfer of CD34+/CD38+ cells to preimmune fetal sheep generated only short-term human hematopoiesis, possibly suggesting that the CD34+/CD38+ cell population contains relatively early multipotent hematopoletic progenitor cells, but not stem cells. This work extends the prior in vitro evidence that the earliest cells in fetal and adult human marrow lack CD38 expression. In summary, the CD34+/ CD38- cell population has a high capacity for long-term multilineage hematopoietic engraftment, suggesting the presence of stem cells in this minor adult human marrow cell subset. 相似文献
98.
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99.