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51.
52.
Distinct conformations of the protein complex p97-Ufd1-Npl4 revealed by electron cryomicroscopy 总被引:1,自引:0,他引:1
Bebeacua C Förster A McKeown C Meyer HH Zhang X Freemont PS 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(4):1098-1103
p97 is a key regulator of numerous cellular pathways and associates with ubiquitin-binding adaptors to remodel ubiquitin-modified substrate proteins. How adaptor binding to p97 is coordinated and how adaptors contribute to substrate remodeling is unclear. Here we present the 3D electron cryomicroscopy reconstructions of the major Ufd1-Npl4 adaptor in complex with p97. Our reconstructions show that p97-Ufd1-Npl4 is highly dynamic and that Ufd1-Npl4 assumes distinct positions relative to the p97 ring upon addition of nucleotide. Our results suggest a model for substrate remodeling by p97 and also explains how p97-Ufd1-Npl4 could form other complexes in a hierarchical model of p97-cofactor assembly. 相似文献
53.
Hughes CM Woodside JV McGartland C Roberts MJ Nicholls DP McKeown PP 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2012,22(4):376-382
Background and aimsPatients with chronic heart failure (CHF) are known to be at risk of malnutrition, and cardiac cachexia is an adverse prognostic indicator. The aim of this study was to determine the dietary adequacy of CHF patients compared with Dietary Reference Values, to compare the nutritional intake and status of CHF patients to a healthy comparison group, and finally to determine whether nutritional intake and status depended on New York Heart Association (NYHA) functional class.Methods and ResultsPatients with CHF (n = 39) and a comparison group of 27 healthy participants, who did not have CHF, were asked to complete a four-day food diary, and energy and nutrient intakes were calculated. F2α-isoprostanes were measured in urine as an indicator of oxidative stress and antioxidants were measured in serum or plasma. Overall 73% of the CHF patients were consuming less than recommended energy intakes, and more than 50% of these patients were also consuming less than recommended vitamin D, selenium and zinc intakes. Nutrient intake (energy, vitamin B6, D, E, iron, folate and riboflavin) was lower in CHF patients than in the comparison group, with vitamin B6 and folate intake and antioxidant status decreasing, and isoprostane status increasing as NYHA functional class increased.ConclusionThe majority of CHF patients do not meet dietary reference values for energy and a range of nutrients, and nutrient intake is lower in CHF patients than in healthy individuals. Dietary inadequacy tends to be increased in those with more severe disease. 相似文献
54.
EJ Revie DW McKeown JA Wilson OJ Garden SJ Wigmore 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2012,14(9):611-618
Objectives
Epidural analgesia is recommended for the provision of analgesia following major abdominal surgery. Continuous local anaesthetic wound infiltration may be an effective alternative. A prospective randomized trial was undertaken to compare these two methods following open liver resection. The primary outcome was length of time required to fulfil criteria for discharge from hospital.Methods
Patients undergoing open liver resection were randomized to receive either epidural (EP group) or local anaesthetic wound infiltration plus patient-controlled opiate analgesia (WI group) for the first 2 days postoperatively. All other care followed a standardized enhanced recovery protocol. Time to fulfil discharge criteria, pain scores, physical activity measurements and complications were recorded.Results
Between August 2009 and July 2010, 65 patients were randomized to EP (n= 32) or WI (n= 33). The mean time required to fulfil discharge criteria was 4.5 days (range: 2.5–63.5 days) in the WI group and 6.0 days (range: 3.0–42.5 days) in the EP group (P= 0.044). During the first 48 h following surgery, pain scores were significantly lower in the EP group both at rest and on movement. Resting pain scores within both groups were rated as mild (range: 0–3). There was no significant difference between the groups in time to first mobilization or overall complication rate (48.5% in the WI group vs. 58.1% in the EP group; P= 0.443).Conclusions
Local anaesthetic wound infiltration combined with patient-controlled opiate analgesia reduces the length of time required to fulfil criteria for discharge from hospital compared with epidural analgesia following open liver resection. Epidural analgesia provides superior analgesia, but does not confer benefits in terms of faster mobilization or recovery. 相似文献55.
巨噬细胞迁移抑制因子最初是由于能抑制体外巨噬细胞随机迁移而被发现,现在它作为一种重要的调节因子参与一系列炎症性疾病过程.我们最近发现,巨噬细胞迁移抑制因子的缺失使一些由炎症介质诱发的白细胞-内皮细胞相互作用减弱,提示巨噬细胞迁移抑制因子在炎症反应中起作用的机制之一是促进白细胞聚集.…… 相似文献
56.
The cytoskeleton in Chediak-Higashi syndrome fibroblasts 总被引:2,自引:0,他引:2
The Chediak-Higashi syndrome (CHS) trait is expressed in cultured human skin fibroblasts as an abnormal perinuclear concentration of moderately enlarged lysosomes. The cytoskeleton of CHS fibroblasts appears intact. Microtubules are normal in number and morphology, as assessed by colchicine binding studies, antitubulin immunofluorescence, and electron microscopy. Deformability by shear force is unaltered and microfilaments are abundant. However, CHS lysosomes appear to interact abnormally with the cytoskeleton, since the perinculear aggregation partially disperses after depolymerization of cell microtubules with colchicine. These results suggest that CHS is associated with a defect of either the lysosomal membrane itself or of lysosomal membrane- microtubule interaction. 相似文献
57.
A five-drug remission induction regimen with intensive consolidation for adults with acute lymphoblastic leukemia: cancer and leukemia group B study 8811 总被引:23,自引:13,他引:23
Larson RA; Dodge RK; Burns CP; Lee EJ; Stone RM; Schulman P; Duggan D; Davey FR; Sobol RE; Frankel SR 《Blood》1995,85(8):2025-2037
The goal of this phase II multicenter clinical trial was to evaluate a new intensive chemotherapy program for adults with untreated acute lymphoblastic leukemia (ALL) and to examine prospectively the impact of clinical and biologic characteristics on the outcome. One hundred ninety-seven eligible and evaluable patients (16 to 80 years of age; median, 32 years of age) received cyclophosphamide, daunorubicin, vincristine, prednisone, and L-asparaginase; 167 patients (85%) achieved a complete remission (CR), 13 (7%) had refractory disease, and 17 (9%) died during induction. A higher CR rate was observed in younger patients (94% for those < 30 years old, 85% for those 30 to 59 years old, and 39% for those > or = 60 years old, P < .001) and in those who had a mediastinal mass (100%) or blasts with a T-cell immunophenotype. Eighty percent of B-lineage and 97% of T-cell ALL patients achieved a CR (P = .01). The coexpression of myeloid antigens did not affect the response rate or duration. Seventy percent of those with cytogenetic or molecular evidence of the Philadelphia (Ph) chromosome and 84% of those without such evidence achieved a CR (P = .11). Patients in remission received multiagent consolidation treatment, central nervous system prophylaxis, late intensification, and maintenance chemotherapy for a total of 24 months. After a median follow-up time of 43 months, the median survival for all 197 patients is 36 months; the median remission duration for the 167 CR patients is 29 months. Favorable pretreatment characteristics relative to remission duration or survival are younger age, the presence of a mediastinal mass or lymphadenopathy, a white blood cell count (WBC) less than 30,000/microL, L1 morphology, T or TMy immunophenotype, and the absence of the Ph chromosome. The estimates of the proportion surviving at 3 years are 69% for patients less than 30 years old, 39% for those 30 to 59 years old, 89% for those who had a mediastinal mass, 59% with WBC less than 30,000/microL, 63% with L1 morphology, 69% for T or TMy antigen expression, and 62% for those who lack the Ph chromosome. Fifteen patients (8%) had no unfavorable prognostic factors and have an estimated probability of survival at 5 years of 100% (95% confidence interval, 77% to 100%). This intensive chemotherapy regimen produces a high remission rate and a high proportion of durable remissions in adults with ALL. 相似文献
58.
The contribution of von Willebrand factor (vWF)-platelet binding to platelet-collagen interaction was examined in vitro. The binding of vWF to platelets was mediated and regulated by ristocetin. Subthreshold concentrations of ristocetin (less than or equal to 1 mg/mL), insufficient to cause ristocetin-induced platelet aggregation (RIPA), were added to platelet-rich plasma (PRP) prior to the addition of collagen. The collagen-induced platelet aggregation (CIPA) was modified by ristocetin and the degree of alteration was dependent on the ristocetin concentration. Response as a function of ristocetin concentration was designated the Collagen-Platelet Aggregation Response (CoI-PAR). In normal PRP the CoI-PAR was a progressive inhibition followed by decreasing inhibition and then an enhanced response. The enhanced response occurred over a narrow range of ristocetin concentrations (0.8 to 1.0 mg/mL). In the absence of vWF (severe von Willebrand's disease, Type I, vWF less than 1%) the CoI-PAR was a progressive, eventually complete inhibition with no enhanced response (with ristocetin concentrations up to 3.0 mg/mL). With addition of vWF to this PRP an enhanced response was observed at a ristocetin concentration inversely proportional to the vWF level. PRP from a patient with severe Hemophilia A showed a response within the normal range. Subthreshold ristocetin did not cause plasma protein precipitation or platelet release of 3H-serotonin, nor induce micro platelet aggregate formation. Digestion of platelet membrane glycoproteins (GP(s] with chymotrypsin demonstrated that upon removal of GPI, RIPA was absent, CIPA retained and the CoI-PAR was progressive inhibition, with no enhancement. With removal of GPs I, II, and III, RIPA, CIPA, and the CoI-PAR were absent. A dose-response 125I-vWF- platelet binding occurred with increasing ristocetin concentrations which was unchanged by the addition of collagen. These results demonstrated that ristocetin-platelet association inhibited CIPA, and vWF-platelet binding enhanced platelet-collagen adhesion and platelet aggregation. The in vitro-enhanced CIPA represents a vWF-dependent aggregation of sufficient magnitude to overcome the inhibitory effect of ristocetin. These studies demonstrate an influential interaction of ristocetin, vWF, and collagen with the platelet membrane and imply an important hemostatic contribution of vWF-platelet binding in platelet- collagen interaction. 相似文献
59.
The common cuttlefish, Sepia officinalis, represents a model mobile marine species for studies of evolutionary processes occurring across a range of spatial and temporal scales. Such studies are relevant to sustainable fishery management and biodiversity conservation as the species is intensely exploited and an important component of inshore marine ecosystems. The isolation and preliminary characterisation of 10 dinucleotide repeat microsatellite loci is described. Genotyping of 48 adults from Agon Coutainville (France) revealed polymorphism at 9 of the loci. Among the polymorphic loci there was an average of 8.8 alleles per locus (range 3–14) with observed and expected heterozygosity per locus ranging from 0.104 to 0.792 and from 0.101 to 0.806, respectively. No evidence of linkage disequilibrium was detected between any locus pair. The loci described here represent a valuable addition to the suite of genetic markers applicable to S. officinalis research. 相似文献
60.
Susan B Roberts Rachel E Silver Sai Krupa Das Roger A Fielding Cheryl H Gilhooly Paul F Jacques Jennifer M Kelly Joel B Mason Nicola M McKeown Meaghan A Reardon Sheldon Rowan Edward Saltzman Barbara Shukitt-Hale Caren E Smith Allen A Taylor Dayong Wu Fang Fang Zhang Karen Panetta Sarah Booth 《Advances in nutrition (Bethesda, Md.)》2021,12(4):1438