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91.
Obesity Surgery - Metabolic dysfunction–associated fatty liver disease–related cirrhosis is possible at the time of bariatric surgery, complicated by further liver decompensation....  相似文献   
92.
Obesity Surgery - Bariatric surgery is the most effective and durable treatment option for clinically severe obesity. Unfortunately, some degree of weight regain (WR) is common after nadir weight...  相似文献   
93.
Kaposi’s sarcoma-associated herpesvirus (KSHV) is a cancer-related herpesvirus. Like other herpesviruses, the KSHV icosahedral capsid includes a portal vertex, composed of 12 protein subunits encoded by open reading frame (ORF) 43, which enables packaging and release of the viral genome into the nucleus through the nuclear pore complex (NPC). Capsid vertex-specific component (CVSC) tegument proteins, which directly mediate docking at the NPCs, are organized on the capsid vertices and are enriched on the portal vertex. Whether and how the portal vertex is selected for docking at the NPC is unknown. Here, we investigated the docking of incoming ORF43-null KSHV capsids at the NPCs, and describe a significantly lower fraction of capsids attached to the nuclear envelope compared to wild-type (WT) capsids. Like WT capsids, nuclear envelope-associated ORF43-null capsids co-localized with different nucleoporins (Nups) and did not detach upon salt treatment. Inhibition of nuclear export did not alter WT capsid docking. As ORF43-null capsids exhibit lower extent of association with the NPCs, we conclude that although not essential, the portal has a role in mediating the interaction of the CVSC proteins with Nups, and suggest a model whereby WT capsids can dock at the nuclear envelope through a non-portal penton vertex, resulting in an infection ‘dead end’.  相似文献   
94.
Antibodies of non-human mammals are glycosylated with carbohydrate antigens, such as galactose-α-1-3-galactose (α-Gal) and N-glycolylneuraminic acid (Neu5Gc). These non-human carbohydrate antigens are highly immunogenic in humans due to loss-of-function mutations of the key genes involved in their synthesis. Such immunogenic carbohydrates are expressed on therapeutic polyclonal rabbit anti-human T-cell IgGs (anti-thymocyte globulin; ATG), the most popular induction treatment in allograft recipients. To decipher the quantitative and qualitative response against these antigens in immunosuppressed patients, particularly against Neu5Gc, which may induce endothelial inflammation in both the graft and the host. We report a prospective study of the antibody response against α-Gal and Neu5Gc-containing glycans following rabbit ATG induction compared to controls. We show a drop in the overall levels of anti-Neu5Gc antibodies at 6 and 12 months post-graft compared to the pre-existing levels due to the major early immunosuppression. However, in contrast, in a cross-sectional study there was a highly significant increase in anti-Neu5Gc IgGs levels at 6 months post-graft in the ATG-treated compared to non-treated patients(P = 0.007), with a clear hierarchy favouring anti-Neu5Gc over anti-Gal response. A sialoglycan microarray analysis revealed that the increased anti-Neu5Gc IgG response was still highly diverse against multiple different Neu5Gc-containing glycans. Furthermore, some of the ATG-treated patients developed a shift in their anti-Neu5Gc IgG repertoire compared with the baseline, recognizing different patterns of Neu5Gc-glycans. In contrast to Gal, Neu5Gc epitopes remain antigenic in severely immunosuppressed patients, who also develop an anti-Neu5Gc repertoire shift. The clinical implications of these observations are discussed.  相似文献   
95.
OBJECTIVE: The efficacy of intravenous cyclosporin (CSA) in acute severe ulcerative colitis (UC) is well established. The aim of this study was to evaluate its efficacy in moderately severe colitis refractory to steroids. METHODS: Twenty-six patients (17 men, mean age 41 +/- 14 yr) with UC refractory to steroids treated with CSA were included in this study. Severity was defined according to Truelove criteria. A clinical activity score below 10 during 2 consecutive days defined clinical response. RESULTS: According to Truelove criteria, all patients had moderate UC. CSA was administered IV at a mean daily dose of 3.7 +/- 0,5 mg/kg until response and then orally for 3.5 +/- 2.6 months. A clinical response was achieved in 20/26 patients (76,9%) within 5.7 +/- 2.8 days (5/6 failures were treated by proctocolectomy). During a follow-up of 27.8 +/- 20.8 months, relapse rate was 60% (12/20): 7 patients underwent proctocolectomy and 5 had clinical remission with CSA retreatment (N=4) and steroids (N=1). At the end of follow-up, 12 patients (46%) were in clinical remission, 12 (46%) required colectomy, 1 had chronic active UC and 1 was lost of follow-up. The probability to avoid surgery was 52% at 78 months. The only factor associated with avoidance of surgery was concomitant treatment with azathioprine (P=0.007). Ten reversible adverse events occurred in 9 patients. CONCLUSION: This study shows that CSA is safe and effective in moderately severe steroid resistant UC. Concomitant treatment with azathioprine significantly decreases the rate of subsequent surgery. CSA may act as a "bridge" until the therapeutic action of azathioprine is achieved for maintenance treatment. These results should be further confirmed by a prospective controlled study.  相似文献   
96.
Proinsulin is a key autoantigen in type 1 diabetes. Evidence in the mouse has underscored the importance of the insulin B chain region in autoimmunity to pancreatic beta cells. In man, a majority of proteasome cleavage sites are predicted by proteasome cleavage algorithms within this region. To study CD8+ T cell responses to the insulin B chain and adjacent C peptide, we selected 8- to 11-mer peptides according to proteasome cleavage patterns obtained by digestion of two peptides covering proinsulin residues 28 to 64. We studied their binding to purified HLA class I molecules and their recognition by T cells from diabetic patients. Peripheral blood mononuclear cells from 17 of 19 recent-onset and 12 of 13 long-standing type 1 diabetic patients produced IFN-gamma in response to proinsulin peptides as shown by using an ELISPOT assay. In most patients, the response was against several class I-restricted peptides. Nine peptides were recognized within the proinsulin region covering residues 34 to 61. Four yielded a high frequency of recognition in HLA-A1 and -B8 patients. Three peptides located in the proinsulin region 41-51 were shown to bind several HLA molecules and to be recognized in a high percentage of diabetic patients.  相似文献   
97.
Patients with T-cell acute lymphoblastic leukemias (T-ALLs) within the Leucemies Aigues Lymphoblastiques de l'Adulte-94 (LALA-94) prospective trial were treated with a 4-drug per 4-week induction, with intermediate-dose cytarabine and mitoxantrone salvage treatment for patients not achieving complete remission (CR) in 1 course. Only the latter received allografts, if possible, thus providing an informative setting for assessing early response. Representative patients with T-ALL (91 patients) were classified into surface T-cell receptor (TCR)-expressing T-ALL patients (TCRalphabeta+ or TCRgammadelta+), pre-alphabeta T-ALL patients (cTCRbeta+, TCR-), and immature (IM) cTCRbeta-, TCR- T-ALL patients; 81 patients underwent genotyping for SIL-TAL1, CALM-AF10, HOX11, and HOX11L2. Overall, CR was obtained in 81 (89%) patients; relapse rate was 62% at 4 years and overall survival (OS) rate was 38%. CR rate was significantly lower in IM T-ALL patients after 1 course (45% vs 87%; P < .001) and after salvage (74% vs 97%; P = .002), with the latter inducing a higher rate of CR (9 [64%] of 14) than initial induction. Once CR was obtained, cumulative relapse rates were similar for IM, pre-alphabeta, and TCR+ T-ALL patients (P = .51), but were higher in HOX11L2 (83%) and SIL-TAL1 (82%) T-ALL patients compared with other genetic subgroups (48%; P = .05). This was associated with an inferior OS for HOX11L2 T-ALLs (13% vs 47% in HOX11L2-T-ALLs; P = .009). The majority of patients with HOX11 T-ALL underwent allografting, predominantly in second CR, but were not associated with a superior OS. Both TCR and genotypic stratification can therefore contribute to risk-adapted management of adult T-ALLs.  相似文献   
98.
Mycoplasmas were examined on the surfaces of tissue culture cells prepared for transmission and scanning electron microscopy. The pleomorphic bodies seen were proved to be mycoplasmas by the use of thin sections, passage of the infection from one cell line to another, and by autoradiography with [(3)H]thymidine both on the sections and the replicas. The mycoplasmas were not always evenly distributed over the cell's surface; their arrangement seemed to correlate with the activity or morphology of the cell. The use of replicas and scanning electron microscopy in routine examination of cultures for mycoplasma contamination is discussed.  相似文献   
99.
We treated 5 patients with polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome and multifocal bone lesions or diffuse bone marrow plasmacytic infiltration with high-dose therapy (HDT) and autologous blood stem cell transplantation. In all cases, the treatment produced remission of plasma cell proliferation associated with marked improvement in the patients' performance status, neurologic symptoms, and other manifestations of the syndrome. HDT with stem cell support should be investigated further as a therapeutic option in patients with POEMS syndrome and disseminated plasma cell dyscrasia.  相似文献   
100.
OBJECTIVES: We investigated the effects of short-term tezosentan treatment on cardiac function, pulmonary edema and long-term evolution of heart failure (HF) in a rat model of myocardial infarction (MI). BACKGROUND: Endothelin (ET) may play a major role in the progression from MI to HF. Tezosentan is a new dual ET(A)/ET(B) receptor antagonist. METHODS: Rats were subjected to coronary artery ligation and were treated with either vehicle or tezosentan (10 mg/kg IV bolus) at 1 h and 24 h after MI. Cardiac hemodynamics and lung weight were measured at 48 h after MI. Survival was assessed over a five-month period. RESULTS: At 48 h after ligation, vehicle-treated rats developed HF, as evidenced by a marked increase in left ventricular end-diastolic pressure (LVEDP), reduction in dP/dt(max) and mean arterial pressure (MAP), and development of pulmonary edema. Tezosentan treatment attenuated the increase in LVEDP and in lung weight and slightly reduced MAP without affecting dP/dt(max). Infarct size was not modified by tezosentan. Despite the fact that treatment with tezosentan was stopped after 24 h, the initial tezosentan administration significantly reduced cardiac hypertrophy (22%) and decreased mortality by 51% at five months (50% survival vs. 19% survival in vehicle-treated rats, p < 0.001). CONCLUSIONS: Tezosentan administered during the first day after MI in rats, in addition to improving acutely hemodynamic conditions, markedly increases long-term survival. This increase is associated with a decrease of pulmonary edema and prevention of cardiac hypertrophy. Tezosentan could be a safe and useful therapeutic agent in the prevention and treatment of ischemic HF.  相似文献   
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