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31.
Beta-thalassemia major patients have chronic anemia and are dependent on blood transfusions to sustain life. Molecular characterization and prenatal diagnosis of beta3-thalassemia is essential in Malaysia because about 4.5% of the population are heterozygous carriers for beta-thalassemia. The high percentage of compound heterozygosity (47.62%) found in beta-thalassemia major patients in the Thalassaemia Registry, University of Malaya Medical Centre (UMMC), Malaysia, also supports a need for rapid, economical, and sensitive protocols for the detection of beta-thalassemia mutations. Molecular characterization of beta-thalassemia mutations in Malaysia is currently carried out using ARMS, which detects a single beta-thalassemia mutation per PCR reaction. We developed and evaluated Combine amplification refractory mutation system (C-ARMS) techniques for efficient molecular detection of two to three beta-thalassemia mutations in a single PCR reaction. Three C-ARMS protocols were evaluated and established for molecular characterization of common beta-thalassemia mutations in the Malay and Chinese ethnic groups in Malaysia. Two C-ARMS protocols (cd 41-42/IVSII #654 and -29/cd 71-72) detected the beta-thalassemia mutations in 74.98% of the Chinese patients studied. The CARMS for cd 41-42/IVSII #654 detected beta-thalassemia mutations in 72% of the Chinese families. C-ARMS for cd 41-42/IVSI #5/cd 17 allowed detection of beta-thalassemia mutations in 36.53% of beta-thalassemia in the Malay patients. C-ARMS for cd 41-42/IVSI #5/cd 17 detected beta-thalassemia in 45.54% of the Chinese patients. We conclude that C-ARMS with the ability to detect two to three mutations in a single reaction provides more rapid and cost-effective protocols for beta-thalassemia prenatal diagnosis and molecular analysis programs in Malaysia. 相似文献
32.
Cho SH Kim TS Lee HW Tsuji M Ishihara C Kim JT Wee SH Lee CG 《The Korean journal of parasitology》2002,40(1):33-40
Attempts were made to isolate and identify Korean bovine Babesia parasite. Blood samples were collected from Holstein cows in Korea, and Babesia parasites were propagated in SCID mice with circulating bovine red blood cells for isolation. The isolate was then antigenically and genotypically compared with several Japanese isolates. The Korean parasite was found to be nearly identical to the Oshima strain isolated from Japanese cattle, which was recently designated as Babesia ovata oshimensis n. var. Haemaphysalis longicornis was the most probable tick species that transmitted the parasite. 相似文献
33.
Human embryonic stem (ES) cells are pluripotent cells with the potential to differentiate into a variety of cell types, which could be used for cell transplantation therapies as well as drug discovery studies. However, the large-scale culture of undifferentiated human ES cells is currently limited by their dependency on mouse embryonic fibroblast feeder layers. The proteomics approach was employed to characterize the environment that supports the growth of undifferentiated human ES cells and to identify factors critical for their independent growth. Conditioned medium from mouse embryonic fibroblast feeder layers, STO cell line, was concentrated and subjected to analyses by two-dimensional electrophoresis mass spectrometry. In total, 136 unique protein species were identified which included some that are known to participate in cell growth and differentiation, extracellular matrix formation and remodeling, in addition to the unexpected but interesting finding of many nominally intracellular proteins. This approach has thus revealed the complexity of the environment provided by the feeder cells and provides a useful starting point for future studies. Moreover, candidates from the initial list of identified proteins can be further investigated for their effects on the growth and differentiation of human ES cells in a defined culture environment. 相似文献
34.
The COP9/signalosome (CSN) is known to remove the stimulatory NEDD8 modification from cullins. The activity of the fission yeast cullins Pcu1p and Pcu3p is dramatically stimulated when retrieved from csn mutants but inhibited by purified CSN. This inhibition is independent of cullin deneddylation but mediated by the CSN-associated deubiquitylating enzyme Ubp12p, which forms a complex with Pcu3p in a CSN-dependent manner. In ubp12 mutants, as in csn mutants, Pcu3p activity is stimulated. CSN is required for efficient targeting of Ubp12p to the nucleus, where both cullins reside. Finally, the CSN/Ubp12p pathway maintains the stability of the Pcu1p-associated substrate-specific adaptor protein Pop1p. We propose that CSN/Ubp12p-mediated deubiquitylation creates an environment for the safe de novo assembly of cullin complexes by counteracting the autocatalytic destruction of adaptor proteins. 相似文献
35.
The COP9 signalosome (CSN) is a highly conserved protein complex implicated in diverse biological functions that involve ubiquitin-mediated proteolysis. Paradoxically, conserved enzymatic activities associated with CSN inhibit cullin ubiquitin ligase activity in vitro, whereas mutational analysis suggests that CSN promotes cullin-dependent proteolysis in vivo. This apparent paradox can be resolved in a model that proposes CSN-mediated cullin inhibition is a prerequisite for the proper assembly and maintenance of active cullin ubiquitin ligase complexes. 相似文献
36.
37.
High Performance Flexible Supercapacitor Electrodes Composed of Ultralarge Graphene Sheets and Vanadium Dioxide
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Little is known regarding the effect of the graphene lateral size on the electrochemical performance of hybrid graphene electrode. This work examines the electrochemical performance of a flexible hybrid supercapacitor electrode composed of ultralarge graphene oxide (UGO; mean lateral size of 47 ± 22 μm) and vanadium dioxide (VO2) nanobelts, referring to a reference electrode composed of small scale graphene oxide (SGO; mean lateral size of 0.8 ± 0.5 μm) and VO2.Thermal treatment converts UGO/VO2 and SGO/VO2 to URGO/VO2 (denoted VURGO) and SRGO/VO2 (denoted VSRGO) electrodes, respectively. The sheet resistance of the VURGO film (0.57 ± 0.03 kΩ sq.–1) was two orders of magnitude lower than that of the VSRGO (55.74 ± 9.35 kΩ sq.–1). The VURGO hybrid electrode showed a specific capacitance of 769 F g?1, which was significantly better than the corresponding values for the VSRGO electrode (385 F/g). These results support the notion that the use of ultralarge graphene sheets (≈22 500 μm2) lowers the intersheet resistance due to the presence of fewer intersheet tunneling barriers. This article highlights the potential utility of URGO (as a conductive support) in hybrid electrode containing VO2 nanobelts for high performance flexible hybrid supercapacitor. 相似文献
38.
Claire H. den Hoedt Muriel P. C. Grooteman Michiel L. Bots Peter J. Blankestijn Ingeborg van der Tweel Neelke C. van der Weerd E. Lars Penne Albert H. A. Mazairac Renée Levesque Piet M. ter Wee Menso J. Nubé Marinus A. van den Dorpel CONTRAST investigators 《PloS one》2015,10(8)
Background
Hemodialysis (HD) patients have a high risk of infections. The uremic milieu has a negative impact on several immune responses. Online hemodiafiltration (HDF) may reduce the risk of infections by ameliorating the uremic milieu through enhanced clearance of middle molecules. Since there are few data on infectious outcomes in HDF, we compared the effects of HDF with low-flux HD on the incidence and type of infections.Patients and Methods
We used data of the 714 HD patients (age 64 ±14, 62% men, 25% Diabetes Mellitus, 7% catheters) participating in the CONvective TRAnsport STudy (CONTRAST), a randomized controlled trial evaluating the effect of HDF as compared to low-flux HD. The events were adjudicated by an independent event committee. The risk of infectious events was compared with Cox regression for repeated events and Cox proportional hazard models. The distributions of types of infection were compared between the groups.Results
Thirty one percent of the patients suffered from one or more infections leading to hospitalization during the study (median follow-up 1.96 years). The risk for infections during the entire follow-up did not differ significantly between treatment arms (HDF 198 and HD 169 infections in 800 and 798 person-years respectively, hazard ratio HDF vs. HD 1.09 (0.88–1.34), P = 0.42. No difference was found in the occurrence of the first infectious event (either fatal, non-fatal or type specific). Of all infections, respiratory infections (25% in HDF, 28% in HD) were most common, followed by skin/musculoskeletal infections (21% in HDF, 13% in HD).Conclusions
HDF as compared to HD did not result in a reduced risk of infections, larger studies are needed to confirm our findings.Trial Registration
ClinicalTrials.gov NCT00205556 相似文献39.
WanFen Yip Charumathi Sabanayagam Boon Wee Teo Wan Ting Tay M. Kamran Ikram E. Shyong Tai Khuan Yew Chow Tien Y. Wong Carol Y. Cheung 《PloS one》2015,10(2)
BackgroundRetinal microvascular signs may provide insights into the structure and function of small vessels that are associated with renal disease. We examined the relationship of retinal microvascular signs with both prevalent and incident end-stage renal disease (ESRD) in a multi-ethnic Asian population.MethodsA total of 5763 subjects (aged ≥40 years) from two prospective population-based studies (the Singapore Malay Eye Study and the Singapore Prospective Study) were included for the current analysis. Retinopathy was graded using the modified Airlie House classification system. Retinal vascular parameters were measured using computer-assisted programs to quantify the retinal vessel widths (arteriolar and venular caliber) and retinal vascular network (fractal dimension). Data on ESRD was obtained by record linkage with the ESRD cases registered by National Registry of Diseases Office, Singapore. Multi-variable adjusted regression analyses were performed to assess the associations of baseline retinal vascular parameters and prevalent and incident ESRD.ResultsAt baseline, 21(0.36%) persons had prevalent ESRD. During a median follow-up of 4.3 years, 33 (0.57%) subjects developed ESRD. In our analyses, retinopathy was associated with prevalent ESRD (multi-variable adjusted odds ratio [OR], 3.21, 95% confidence interval [CI]: 1.28–8.05) and incident ESRD (multi-variable adjusted hazard ratio [HR], 2.51, 95%CI: 1.14–5.54). This association was largely seen in person with diabetes (HR, 2.60, 95%CI: 1.01–6.66) and not present in persons without diabetes (HR, 1.65, 95%CI: 0.14–18.98). Retinal arteriolar caliber, retinal venular caliber and retinal vascular fractal dimension were not associated with ESRD.ConclusionRetinopathy signs in persons with diabetes are related to an increased risk of ESRD; however, other microvascular changes in the retina are not associated with ESRD. 相似文献
40.
Kavita Venkataraman Luor Shyuan Maudrene Tan Dianne Carrol Tan Bautista Konstadina Griva Yasmin Laura Marie Zuniga Mohamed Amir Yung Seng Lee Jeannette Lee E. Shyong Tai Eric Yin Hao Khoo Hwee Lin Wee 《PloS one》2015,10(9)