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91.
Denise C. Carty Daniel J. Kruger Tonya M. Turner Bettina Campbell E. Hill DeLoney E. Yvonne Lewis 《Journal of urban health》2011,88(1):84-97
Many community-based participatory research (CBPR) partnerships address social determinants of health as a central consideration.
However, research studies that explicitly address racism are scarce in the CBPR literature, and there is a dearth of available
community-generated data to empirically examine how racism influences health disparities at the local level. In this paper,
we provide results of a cross-sectional, population-based health survey conducted in the urban areas of Genesee and Saginaw
Counties in Michigan to assess how a sustained community intervention to reduce racism and infant mortality influenced knowledge,
beliefs, and experiences of racism and to explore how perceived racism is associated with self-rated health and birth outcomes.
We used ANOVA and regression models to compare the responses of intervention participants and non-participants as well as
African Americans and European Americans (N = 629). We found that intervention participants reported greater acknowledgment of the enduring and differential impact of
racism in comparison to the non-intervention participants. Moreover, survey analyses revealed that racism was associated with
health in the following ways: (1) experiences of racial discrimination predicted self-rated physical health, mental health,
and smoking status; (2) perceived racism against one’s racial group predicted lower self-rated physical health; and (3) emotional
responses to racism-related experiences were marginally associated with lower birth-weight births in the study sample. Our
study bolsters the published findings on perceived racism and health outcomes and highlights the usefulness of CBPR and community
surveys to empirically investigate racism as a social determinant of health. 相似文献
92.
Bettina Stolp Andrea Imle Fernanda Matos Coelho Miroslav Hons Roser Gorina Ruth Lyck Jens V. Stein Oliver T. Fackler 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(45):18541-18546
HIV-1 negative factor (Nef) elevates virus replication and contributes to immune evasion in vivo. As one of its established in vitro activities, Nef interferes with T-lymphocyte chemotaxis by reducing host cell actin dynamics. To explore Nef’s influence on in vivo recirculation of T lymphocytes, we assessed lymph-node homing of Nef-expressing primary murine lymphocytes and found a drastic impairment in homing to peripheral lymph nodes. Intravital imaging and 3D immunofluorescence reconstruction of lymph nodes revealed that Nef potently impaired T-lymphocyte extravasation through high endothelial venules and reduced subsequent parenchymal motility. Ex vivo analyses of transendothelial migration revealed that Nef disrupted T-lymphocyte polarization and interfered with diapedesis and migration in the narrow subendothelial space. Consistently, Nef specifically affected T-lymphocyte motility modes used in dense environments that pose high physical barriers to migration. Mechanistically, inhibition of lymph node homing, subendothelial migration and cell polarization, but not diapedesis, depended on Nef’s ability to inhibit host cell actin remodeling. Nef-mediated interference with in vivo recirculation of T lymphocytes may compromise T-cell help and thus represents an important mechanism for its function as a HIV pathogenicity factor. 相似文献
93.
Irving PM Alstead EM Greaves RR Feakins RM Pollok RC Rampton DS 《European journal of gastroenterology & hepatology》2005,17(12):1429-1432
We present four cases of acute mesenteric infarction in patients with active ulcerative colitis: one presenting prior to the diagnosis of ulcerative colitis, two at the time of diagnosis, and one many years after the diagnosis had been made. Intestinal ischaemia is an important part of the differential diagnosis in patients with ulcerative colitis presenting with abdominal pain. Conversely, in patients presenting with bloody diarrhoea after mesenteric ischaemia, ulcerative colitis should be considered. 相似文献
94.
95.
Libani IV Guy EC Melchiori L Schiro R Ramos P Breda L Scholzen T Chadburn A Liu Y Kernbach M Baron-Lühr B Porotto M de Sousa M Rachmilewitz EA Hood JD Cappellini MD Giardina PJ Grady RW Gerdes J Rivella S 《Blood》2008,112(3):875-885
In β-thalassemia, the mechanism driving ineffective erythropoiesis (IE) is insufficiently understood. We analyzed mice affected by β-thalassemia and observed, unexpectedly, a relatively small increase in apoptosis of their erythroid cells compared with healthy mice. Therefore, we sought to determine whether IE could also be characterized by limited erythroid cell differentiation. In thalassemic mice, we observed that a greater than normal percentage of erythroid cells was in S-phase, exhibiting an erythroblast-like morphology. Thalassemic cells were associated with expression of cell cycle–promoting genes such as EpoR, Jak2, Cyclin-A, Cdk2, and Ki-67 and the antiapoptotic protein Bcl-XL. The cells also differentiated less than normal erythroid ones in vitro. To investigate whether Jak2 could be responsible for the limited cell differentiation, we administered a Jak2 inhibitor, TG101209, to healthy and thalassemic mice. Exposure to TG101209 dramatically decreased the spleen size but also affected anemia. Although our data do not exclude a role for apoptosis in IE, we propose that expansion of the erythroid pool followed by limited cell differentiation exacerbates IE in thalassemia. In addition, these results suggest that use of Jak2 inhibitors has the potential to profoundly change the management of this disorder. 相似文献
96.
de Vries-Sluijs TE Hansen BE van Doornum GJ Springeling T Evertsz NM de Man RA van der Ende ME 《The Journal of infectious diseases》2008,197(2):292-294
Double-dose hepatitis B virus revaccination of human immunodeficiency virus (HIV)-infected patients proved to be effective in 50.7% of 144 patients who had previously failed to respond to standard doses. In the multivariate analysis, female patients were found to have a significantly better response (P= .03). The effect of age on the response depended on the viral load at the time of revaccination. For patients with a detectable HIV RNA load, the effect of age was stronger (odds ratio [OR], 0.34 per 10 years older [95% confidence interval {CI}, 0.16-0.72]; P= .005) than for patients with an undetectable HIV RNA load (OR, 0.74 per 10 years older [95% CI, 0.50-1.09]; P= .12). 相似文献
97.
98.
Liu Y Hangoc G Campbell TB Goodman M Tao W Pollok K Srour EF Broxmeyer HE 《Experimental hematology》2008,36(8):947-956
OBJECTIVE: Human cord blood (CB) is a potential source of hematopoietic stem cells (HSC) for gene therapy to treat patients with hematopoietic disorders. However, limited numbers of CB CD34(+) cells, low transduction efficiency with lentiviral vectors (LVs), and low engraftment efficiency of nonobese diabetic/severe combined immunodeficient (NOD/SCID) repopulating cells (SRC), a measure of HSC, are blocks to this procedure. To optimize culture and transduction conditions, we compared various lengths of time for prestimulation before transduction, transduction duration, and posttransduction cell culture. MATERIALS AND METHODS: We used a LV to transduce human CB CD34(+) cells followed by engraftment into NOD/SCID mice. We evaluated the effects of prestimulation and transduction time and optimized ex vivo cell culture duration before transplantation. RESULTS: We were able to achieve up to 40% transduction efficiency and up to 50% engraftment efficiency of SRC in CB CD34(+) cells when CB CD34(+) cells were either not prestimulated or prestimulated in 1% fetal bovine serum medium for 1 hour, followed by 5 hours transduction and 3 days culture in a cocktail of growth factors after transduction. No apparent functional changes of CB CD34(+) cells were noted under these conditions. CONCLUSION: This gene-transduction/cell-expansion protocol is the first systematic study to optimize prestimulation time, transduction time, and, very importantly, ex vivo culture time after transduction, and may be of use for LV gene transduction in a gene therapy setting. 相似文献
99.
100.
Paul Declerck Georgios Bakalos Elias Zintzaras Bettina Barton Thomas Schreitmüller 《Clinical therapeutics》2018,40(5):798-809.e2