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排序方式: 共有1271条查询结果,搜索用时 31 毫秒
71.
72.
Nolan TW 《BMJ (Clinical research ed.)》2000,320(7237):771-773
73.
Celia van der Merwe Ben Loos Chrisna Swart Craig Kinnear Franclo Henning Lize van der Merwe Komala Pillay Nolan Muller Dan Zaharie Lize Engelbrecht Jonathan Carr Soraya Bardien 《Biochemical and biophysical research communications》2014
Parkinson’s disease (PD), defined as a neurodegenerative disorder, is characterized by the loss of dopaminergic neurons in the substantia nigra in the midbrain. Loss-of-function mutations in the parkin gene are a major cause of autosomal recessive, early-onset PD. Parkin has been implicated in the maintenance of healthy mitochondria, although previous studies show conflicting findings regarding mitochondrial abnormalities in fibroblasts from patients harboring parkin-null mutations. The aim of the present study was to determine whether South African PD patients with parkin mutations exhibit evidence for mitochondrial dysfunction. Fibroblasts were cultured from skin biopsies obtained from three patients with homozygous parkin-null mutations, two heterozygous mutation carriers and two wild-type controls. Muscle biopsies were obtained from two of the patients. The muscle fibers showed subtle abnormalities such as slightly swollen mitochondria in focal areas of the fibers and some folding of the sarcolemma. Although no differences in the degree of mitochondrial network branching were found in the fibroblasts, ultrastructural abnormalities were observed including the presence of electron-dense vacuoles. Moreover, decreased ATP levels which are consistent with mitochondrial dysfunction were observed in the patients’ fibroblasts compared to controls. Remarkably, these defects did not manifest in one patient, which may be due to possible compensatory mechanisms. These results suggest that parkin-null patients exhibit features of mitochondrial dysfunction. Involvement of mitochondria as a key role player in PD pathogenesis will have important implications for the design of new and more effective therapies. 相似文献
74.
Jie Jia Nolan Frantz Christina Khoo Glenn R. Gibson Robert A. Rastall & Anne L. McCartney 《FEMS microbiology ecology》2010,71(2):304-312
Diarrhoea is a common problem in dogs and can result in disturbance of the normal intestinal microbiota. However, little is known about the gastrointestinal microbiota of dogs with chronic diarrhoea and controlled canine studies of dietary management are scarce. The aims of this study were to investigate the predominant faecal microbiota of chronic diarrhoea dogs and to examine the effect(s) of a fibre blend on the canine faecal microbiota. A 3-week fibre supplementation feeding study was performed in nine chronic diarrhoea and eight control dogs. Atopobium cluster, Lactobacillus–Enterococcus group and Clostridium cluster XIV were the predominant bacterial groups in all dogs. Chronic diarrhoea dogs had significantly higher Bacteroides counts at baseline and significantly lower Atopobium cluster counts following fibre supplementation compared with control dogs. Atopobium cluster levels increased significantly in control dogs, while counts of sulphate-reducing bacteria decreased significantly and Clostridium clusters I and II counts increased significantly in chronic diarrhoea dogs during fibre supplementation. Microbial profiles (detected by denaturing gradient gel electrophoresis) demonstrated interindividual variation, with greater similarity seen between the chronic diarrhoea and control dogs' profiles after fibre supplementation compared with baseline. In conclusion, fibre supplementation induced changes in the canine faecal microbiota, with greater resemblance between the microbiota of chronic diarrhoea and control dogs after this dietary modulation. 相似文献
75.
76.
Dempewolf H Kane NC Ostevik KL Geleta M Barker MS Lai Z Stewart ML Bekele E Engels JM Cronk QC Rieseberg LH 《Molecular ecology resources》2010,10(6):1048-1058
We present an EST library, chloroplast genome sequence, and nuclear microsatellite markers that were developed for the semi-domesticated oilseed crop noug (Guizotia abyssinica) from Ethiopia. The EST library consists of 25 711 Sanger reads, assembled into 17 538 contigs and singletons, of which 4781 were functionally annotated using the Arabidopsis Information Resource (TAIR). The age distribution of duplicated genes in the EST library shows evidence of two paleopolyploidizations—a pattern that noug shares with several other species in the Heliantheae tribe (Compositae family). From the EST library, we selected 43 microsatellites and then designed and tested primers for their amplification. The number of microsatellite alleles varied between 2 and 10 (average 4.67), and the average observed and expected heterozygosities were 0.49 and 0.54, respectively. The chloroplast genome was sequenced de novo using Illumina’s sequencing technology and completed with traditional Sanger sequencing. No large re-arrangements were found between the noug and sunflower chloroplast genomes, but 1.4% of sites have indels and 1.8% show sequence divergence between the two species. We identified 34 tRNAs, 4 rRNA sequences, and 80 coding sequences, including one region (trnH-psbA) with 15% sequence divergence between noug and sunflower that may be particularly useful for phylogeographic studies in noug and its wild relatives. 相似文献
77.
Jessica AB van Nies Rute B Marques Stella Trompet Zuzana de Jong Fina AS Kurreeman Rene EM Toes J Wouter Jukema Tom WJ Huizinga Annette HM van der Helm-van Mil 《Arthritis research & therapy》2010,12(2):R38
Introduction
Recently an association between a genetic variation in TRAF1/C5 and mortality from sepsis or cancer was found in rheumatoid arthritis (RA). The most prevalent cause of death, cardiovascular disease, may have been missed in that study, since patients were enrolled at an advanced disease stage. Therefore, we used an inception cohort of RA patients to investigate the association between TRAF1/C5 and cardiovascular mortality, and replicate the findings on all-cause mortality. As TRAF1/C5 associated mortality may not be restricted to RA, we also studied a large cohort of non-RA patients. 相似文献78.
Intervention with mesenchymal stem cells (MSCs) represents a promising therapeutic tool in treatment-refractory autoimmune
diseases. A new report by Schurgers and colleagues in a previous issue of Arthritis Research & Therapy sheds novel mechanistic insight into the pathways employed by MSCs to suppress T-cell proliferation in vitro, but, at the same time, indicates that MSCs do not influence T-cell reactivity and the disease course in an in vivo arthritis model. Such discrepancies between the in vitro and in vivo effects of potent cellular immune modulators should spark further research and should be interpreted as a sign of caution
for the in vitro design of MSC-derived interventions in the setting of human autoimmune diseases. 相似文献
79.
80.
Kartchner Caverns in Benson, AZ, was opened for tourism in 1999 after a careful development protocol that was designed to
maintain predevelopment conditions. As a part of an ongoing effort to determine the impact of humans on this limestone cave,
samples were collected from cave rock surfaces along the cave trail traveled daily by tour groups (200,000 visitors year–1) and compared to samples taken from areas designated as having medium (30–40 visitors year–1) and low (2–3 visitors year–1) levels of human exposure. Samples were also taken from fiberglass moldings installed during cave development. Culturable
bacteria were recovered from these samples and 90 unique isolates were identified by using 16S rRNA polymerase chain reaction
and sequencing. Diversity generally decreased as human impact increased leading to the isolation of 32, 27, and 22 strains
from the low, medium, and high impact areas, respectively. The degree of human impact was also reflected in the phylogeny
of the isolates recovered. Although most isolates fell into one of three phyla: Actinobacteria, Firmicutes, or Proteobacteria,
the Proteobacteria were most abundant along the cave trail (77% of the isolates), while Firmicutes predominated in the low
(66%) and medium (52%) impact areas. Although the abundance of Proteobacteria along the cave trail seems to include microbes
of environmental rather than of anthropogenic origin, it is likely that their presence is a consequence of increased organic
matter availability due to lint and other organics brought in by cave visitors. Monitoring of the cave is still in progress
to determine whether these bacterial community changes may impact the future development of cave formations. 相似文献