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911.
Monika Sarkar Peter Bacchetti Phyllis Tien Elizabeth Mileti Audrey L. French Brian R. Edlin Marla Keller Eric Seaberg Marek J. Nowicki Mary Young Marion G. Peters 《Digestive diseases and sciences》2013,58(5):1341-1348
Background/Aims
Among individuals without human immunodeficiency virus (HIV), African Americans have lower spontaneous clearance of hepatitis C virus (HCV) than Caucasians, and women have higher clearance than men. Few studies report racial/ethnic differences in acute HCV in HIV infected, or Hispanic women. We examined racial/ethnic differences in spontaneous HCV clearance in a population of HCV mono- and co-infected women.Methods
We conducted a cross sectional study of HCV seropositive women (897 HIV infected and 168 HIV uninfected) followed in the US multicenter, NIH-funded Women’s Interagency HIV Study (WIHS), to determine the association of race/ethnicity with spontaneous HCV clearance, as defined by undetectable HCV RNA at study entry.Results
Among HIV and HCV seropositive women, 18.7 % were HCV RNA negative, 60.9 % were African American, 19.3 % Hispanic and 17.7 % Caucasian. HIV infected African American women were less likely to spontaneously clear HCV than Hispanic (OR 0.59, 95 % CI 0.38–0.93, p = 0.022) or Caucasian women (OR 0.57, 95 % CI 0.36–0.93, p = 0.023). Among HIV uninfected women, African Americans had less HCV clearance than Hispanics (OR 0.18, 95 % CI 0.07–0.48, p = 0.001) or Caucasians (OR 0.26, 95 % CI 0.09–0.79, p = 0.017). There were no significant differences in HCV clearance between Hispanics and Caucasians, among either HIV infected (OR 0.97, 95 % CI 0.57–1.66, p = 0.91) or uninfected (OR 1.45, 95 % CI 0.56–3.8, p = 0.45) women.Conclusions
African Americans were less likely to spontaneously clear HCV than Hispanics or Caucasians, regardless of HIV status. No significant differences in spontaneous HCV clearance were observed between Caucasian and Hispanic women. Future studies incorporating IL28B genotype may further explain these observed racial/ethnic differences in spontaneous HCV clearance. 相似文献912.
David Janson Marion Rietveld Rein Willemze Abdoelwaheb El Ghalbzouri 《Biogerontology》2013,14(2):131-140
Serial passaging has a profound effect on primary cells. Since serially passaged cells show signs of cellular aging, serial passaging is used as an in vitro model of aging. To relate the effect of in vitro aging more to in vivo aging, we generated human skin equivalents (HSEs). We investigated if HSEs generated with late passage fibroblasts show characteristics of aged skin when compared with HSEs generated with early passage fibroblasts. Late passage fibroblasts had enlarged cell bodies and were more often positive for myofibroblast marker α-smooth muscle actin, senescence associated β-galactosidase and p16 compared with early passage fibroblasts. Skin equivalents generated with late passage fibroblasts had a thinner dermis, which could partly be explained by increased matrix metalloproteinase-1 secretion. In equivalents generated with late passage fibroblasts epidermal expression of keratin 6 was increased, and of keratin 10 slightly decreased. However, epidermal proliferation, epidermal thickness and basement membrane formation were not affected. In conclusion, compared with HSEs generated with early passage fibroblasts, HSEs generated with late passage fibroblasts showed changes in the dermis, but no or minimal changes in the basement membrane and the epidermis. 相似文献
913.
Isabelle Ginon Evelyne Decullier Gerard Finet Jean-Francois Cordier Denis Marion Jean-Christophe Saurin Sophie Dupuis-Girod 《European Journal of Internal Medicine》2013,24(3):e35-e39
BackgroundHHT patients with liver vascular malformations (VMs) may develop high-output cardiac failure requiring liver transplant in few cases.ObjectiveOur aim is to show that echocardiography is a good tool to evaluate the severity of hepatic vascular malformations in HHT and can improve medical management in HHT patients.MethodsThe study is a cross-sectional study of cardiac parameters in HHT patients with dyspnea in a single referral center. All HHT patients with dyspnea, consecutively seen at HHT reference center in Lyon between May 2007 and November 2009 were included and had hepatic vascular Ultrasound and Echocardiography. Echocardiographic measures included cardiac output (CO) and index (CI), left ventricle (LV) filling pressures, and pulmonary artery pressure. Then, patients were classified in 4 groups according to the severity: group 1 (normal values), group 2 with isolated high CI, group 3 with high CI and increased LV-filling pressures and group 4 with increased LV-filling pressures and pulmonary hypertension.ResultsFifty-two HHT-patients were analyzed. Eight patients were in group 1, 25 in group 2, 6 in group 3 and 13 in group 4. Age, NYHA class dyspnea, edema, atrial fibrillation, hepatic artery diameter, and BNP (brain natriuretic peptide) levels significantly increased from groups 1 to 4 as well as left atrial area, and presence of mitral regurgitation. Patients with associated pulmonary VMs (n = 11) did not show any clinical or echocardiographic differences.ConclusionPerforming echocardiography in HHT patients with dyspnea allowed us to better understand the physiological processes of high-CO failure complicating liver vascular malformations and may improve follow-up of patients and treatment decisions. 相似文献
914.
Marion R. Wofford MD MPH ; Margaret Miller Davis MD ; Kimberly G. Harkins MD ; Deborah S. King MD PharmD ; Sharon B. Wyatt MD PhD RN CS ; Daniel W. Jones MD 《Journal of clinical hypertension (Greenwich, Conn.)》2000,4(3):189-196
Obesity, now recognized as an independent risk factor for cardiovascular disease, is closely associated with hypertension. Complex mechanisms link increasing body weight with increasing blood pressure. Treatment of the obese patient with hypertension requires consideration of physiologic changes related to obesity hypertension. Lifestyle modification, including weight reduction and increased physical activity, can directly influence blood pressure levels and improve blood pressure control in obese, hypertensive patients. Clinical trials are needed to determine the most effective antihypertensive drugs for the obese, hypertensive patient. Antiobesity drugs offer viable adjunctive pharmacotherapy for obesity hypertension, but additional long-term studies are needed to support their safety and efficacy. 相似文献
915.
Pascal E. Sanchez Raafat P. Fares Jean-Jacques Risso Chantal Bonnet Sandrine Bouvard Marion Le-Cavorsin Béatrice Georges Colette Moulin Amor Belmeguenai Jacques Bodennec Anne Morales Jean-Marc Pequignot Etienne-Emile Baulieu Robert A. Levine Laurent Bezin 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(24):9848-9853
Erythropoietin receptor (EpoR) binding mediates neuroprotection by endogenous Epo or by exogenous recombinant human (rh)Epo. The level of EpoR gene expression may determine tissue responsiveness to Epo. Thus, harnessing the neuroprotective power of Epo requires an understanding of the Epo–EpoR system and its regulation. We tested the hypothesis that neuronal expression of EpoR is required to achieve optimal neuroprotection by Epo. The ventral limbic region (VLR) in the rat brain was used because we determined that its neurons express minimal EpoR under basal conditions, and they are highly sensitive to excitotoxic damage, such as occurs with pilocarpine-induced status epilepticus (Pilo-SE). We report that (i) EpoR expression is significantly elevated in nearly all VLR neurons when rats are subjected to 3 moderate hypoxic exposures, with each separated by a 4-day interval; (ii) synergistic induction of EpoR expression is achieved in the dorsal hippocampus and neocortex by the combination of hypoxia and exposure to an enriched environment, with minimal increased expression by either treatment alone; and (iii) rhEpo administered after Pilo-SE cannot rescue neurons in the VLR, unless neuronal induction of EpoR is elicited by hypoxia before Pilo-SE. This study thus demonstrates using environmental manipulations in normal rodents, the strict requirement for induction of EpoR expression in brain neurons to achieve optimal neuroprotection. Our results indicate that regulation of EpoR gene expression may facilitate the neuroprotective potential of rhEpo. 相似文献
916.
Els Troost Marion Delcroix Marc Gewillig Kristien Van Deyk Werner Budts 《Catheterization and cardiovascular interventions》2009,73(2):173-179
Aims: A significant number of patients with pulmonary hypertension are resistant to medical therapy. We wanted to evaluate whether the modified technique of stent fenestration of the interatrial septum would be feasible and safe, and offer clinical benefit. Methods and Results: The medical records of all patients with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension who underwent a stent fenestration of the interatrial septum between 2001 and 2008 were reviewed. In all fifteen patients (12 female, mean age 48.2 ± 20.5 years) a successful fenestration procedure could be performed. Median follow‐up time between diagnosis and fenestration was 2.3 years (range from 0.5 to 18.6 years). Mean event free survival since diagnosis and after septostomy was 9.8 ± 2.9 and 3.2 ± 0.8 years, respectively. When one extreme outlier was excluded, the 6 min walk distance improved significantly from 309 ± 69 m immediately before fenestration to 374 ± 84 m, 3–4 months after fenestration (n = 8, paired t‐test, P = 0.03). No stent occlusion occurred. Conclusion: The modified stent fenestration technique is feasible and safe in patients with severe pulmonary hypertension. In a selected group of patients, functional capacity might improve although disease progression continues. © 2008 Wiley‐Liss, Inc. 相似文献
917.
Sarita A. Y. Hartgring Joel A. G. van Roon Marion Wenting‐van Wijk Kim M. G. Jacobs Zalima N. Jahangier Cynthia R. Willis Johannes W. J. Bijlsma Floris P. J. G. Lafeber 《Arthritis \u0026amp; Rheumatology》2009,60(9):2595-2605
Objective
To evaluate the expression and functional ability of the high‐affinity interleukin‐7 receptor (IL‐7Rα) in patients with rheumatoid arthritis (RA).Methods
Expression of IL‐7Rα and IL‐7 was determined in synovial tissue from RA patients and was compared with that in synovial tissue from patients with undifferentiated arthritis (UA) and osteoarthritis (OA). IL‐7Rα expression on CD4 T cells, CD19 B cells, and CD14 monocyte/macrophages from RA synovial tissue, synovial fluid, and peripheral blood was also assessed. The proliferative capacity of IL‐7Rαbright and IL‐7Rαdim/− T cells was measured. In addition, we examined IL‐7R blockade with soluble human IL‐7Rα (hIL‐7Rα) in the prevention of immune activation of peripheral blood mononuclear cells.Results
We found significantly higher IL‐7Rα expression in RA and UA synovial tissue than in OA synovial tissue, and the level of IL‐7Rα expression correlated significantly with the levels of CD3 and IL‐7 expression. CD4 T cells from RA synovial fluid and synovial tissue strongly expressed IL‐7Rα. A substantial percentage of B cells and macrophages from RA synovial fluid and synovial tissue also expressed IL‐7Rα, although less prominently than T cells. We found that peripheral blood IL‐7Rαbright T cells that did not express FoxP3 were highly proliferative as compared with IL‐7Rαdim/− T cells that did express high levels of FoxP3. Soluble hIL‐7Rα inhibited IL‐7–induced proliferation and interferon‐γ production by mononuclear cells from RA patients.Conclusion
Our data suggest that enhanced expression of IL‐7Rα and IL‐7 in RA patients contributes significantly to the joint inflammation by activating T cells, B cells, and macrophages. The inhibition of IL‐7R–mediated immune activation by soluble hIL‐7Rα further indicates an important role of IL‐7Rα in inflammatory responses in RA, suggesting IL‐7Rα as a therapeutic target for immunotherapy in RA.918.
Corsten MF Papageorgiou A Verhesen W Carai P Lindow M Obad S Summer G Coort SL Hazebroek M van Leeuwen R Gijbels MJ Wijnands E Biessen EA De Winther MP Stassen FR Carmeliet P Kauppinen S Schroen B Heymans S 《Circulation research》2012,111(4):415-425
Rationale: Viral myocarditis results from an adverse immune response to cardiotropic viruses, which causes irreversible myocyte destruction and heart failure in previously healthy people. The involvement of microRNAs and their usefulness as therapeutic targets in this process are unknown. Objective: To identify microRNAs involved in viral myocarditis pathogenesis and susceptibility. Methods and Results: Cardiac microRNAs were profiled in both human myocarditis and in Coxsackievirus B3-injected mice, comparing myocarditis-susceptible with nonsusceptible mouse strains longitudinally. MicroRNA responses diverged depending on the susceptibility to myocarditis after viral infection in mice. MicroRNA-155, -146b, and -21 were consistently and strongly upregulated during acute myocarditis in both humans and susceptible mice. We found that microRNA-155 expression during myocarditis was localized primarily in infiltrating macrophages and T lymphocytes. Inhibition of microRNA-155 by a systemically delivered LNA-anti-miR attenuated cardiac infiltration by monocyte-macrophages, decreased T lymphocyte activation, and reduced myocardial damage during acute myocarditis in mice. These changes were accompanied by the derepression of the direct microRNA-155 target PU.1 in cardiac inflammatory cells. Beyond the acute phase, microRNA-155 inhibition reduced mortality and improved cardiac function during 7 weeks of follow-up. Conclusions: Our data show that cardiac microRNA dysregulation is a characteristic of both human and mouse viral myocarditis. The inflammatory microRNA-155 is upregulated during acute myocarditis, contributes to the adverse inflammatory response to viral infection of the heart, and is a potential therapeutic target for viral myocarditis. 相似文献
919.
Strullu M Rialland F Cahu X Brissot E Corradini N Thomas C Blin N Rialland X Méchinaud F Mohty M 《European journal of haematology》2012,88(6):504-509
This single-center retrospective study reported the outcome of 19 children treated with a reduced-intensity conditioning (RIC) regimen prior to allogeneic stem cell transplantation (allo-SCT), for hematologic malignancies (n = 17), bone marrow failure (n = 1), and neuroblastoma (n = 1). Children were ineligible for standard myeloablative conditioning because of severe comorbidities (n = 9), a previous auto or allo-SCT (n = 7) or a prior history of extensive chemotherapy (n = 3). All patients underwent a fludarabine-based RIC regimen, and received grafts from matched-related donors (n = 5), match-unrelated donors (n = 6), or unrelated cord blood (UCB, n = 8). In this series, two patients treated with UCB failed to engraft and 63% achieved full donor chimerism at day 100 after allo-SCT. With a median follow-up of 537 d (range, 115-4136), treatment-related mortality was 16% and overall survival was 47%. The principal cause of death was disease relapse (n = 7). Acute graft versus host disease (GVHD) occurred in 53% of patients, while only 10% developed extensive chronic GVHD. Overall, results from this series suggest that RIC allo-SCT can be a valid alternative treatment option in unfit children with malignant hematological diseases. Prospective studies are needed to enlarge pediatric experience in this domain and better identify those children more suitable for a RIC allo-SCT approach. 相似文献
920.
OBJECTIVES: To compare, by sex, selected behavioral and biologic characteristics among normotensive, white-coat hypertensive, and essential hypertensive patients, and to assess the similarities and differences in these characteristics between men and women diagnosed as having white-coat hypertension. METHODS: The subjects of this study were 764 men (80 normotensives, 112 white-coat hypertensives, and 572 essential hypertensives) and 442 women (53 normotensives, 81 white-coat hypertensives and 308 essential hypertensives) who were a nonrandom subset of a larger cohort of patients being assessed to determine the prognostic significance of ambulatory blood pressure measurements. Physician-measured technician-measured and ambulatory (average awake and asleep) blood pressures, daytime blood pressure variability, the difference between awake and sleeping blood pressures, cholesterol levels, plasma renin activity (PRA) and anthropometric and demographic characteristics were compared across the patient classifications within each sex group and between male and female white-coat hypertensives using one-way analysis of variance. Student's t tests and chi squared analysis. RESULTS: Among men, cholesterol levels of normotensives were significantly lower than those of either white-coat or essential hypertensives (P < 0.05 and P < 0.01, respectively). White-coat hypertensives were significantly younger than the essential hypertensives. The ambulatory and technician-measured blood pressures of the white-coat hypertensives were similar to those of the normotensives, as were most measures of variability of blood pressure. Among women, there were no differences in cholesterol level; however, white-coat hypertensives had lower PRA than did the essential hypertensives (P < 0.01) In contrast to the men, women with white-coat hypertension were similar in age to those with essential hypertension, and 10 years older than normotensives (P < 0.01). The ambulatory blood pressures of white-coat hypertensives were similar to those of normotensives, but their technician-measured blood pressures were intermediate between those of the normotensive and essential hypertensive groups. The daily variability of diastolic blood pressure among the white-coat-hypertensive women was greater than that of the normotensive women and similar to that of the essential hypertensive women. For all other measures of variability, data for white-coat-hypertensive women were similar to those for the normotensive women. There was no anthropometric or demographic difference among the patients either for men or for women. White-coat-hypertensive women were older than white-coat-hypertensive men and had higher systolic blood pressures and variabilities of blood pressure (P < 0.05). They also had lower PRA. CONCLUSIONS: These results are consistent with the ideas that the phenomenon of white-coat hypertension is similar for the two sexes, women may exhibit white-coat hypertension at a greater age than do men, and women with white-coat hypertension may further exhibit a broader white-coat effect, reflected in blood pressures measured by other medical personnel. 相似文献