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71.
Lupus nephritis is a major contributor to morbidity and mortality in systemic lupus erythematosus, but little is known about the pathogenic processes that underlie the progressive decay in renal function. A common finding in lupus nephritis is thickening of glomerular basement membranes associated with immune complex deposition. It has been speculated that alterations in the synthesis or degradation of membrane components might contribute to such changes, and thereby to initiation and progression of nephritis through facilitation of immune complex deposition. Matrix metalloproteinases (MMPs) are enzymes that are intimately involved in the turnover of major glomerular basement membrane constituents, including collagen IV and laminins. Alterations in the expression and activity of MMPs have been described in a number of renal diseases, suggesting their relevance to the pathogenesis of various glomerulopathies. The same is true for their natural inhibitors, the tissue inhibitor of metalloproteinase family. Recent data from our group have identified an increase in proteolytic activity within the glomerulus coinciding with the development of proteinuria in the mouse model of systemic lupus erythematosus. (NXB × NZW)F1 Here we review current understanding of MMP/tissue inhibitor of metalloproteinase function within the kidney, and discuss their possible involvement in the development and progression of lupus nephritis.  相似文献   
72.
赤红壤早稻田甲烷排放通量及其影响因素   总被引:5,自引:0,他引:5  
用封闭箱法对广东省赤红壤早稻田CH4排放通量进行了观测。结果表明,CH4排放有明显的季节变化规律,3个排放高峰分别出现在水稻分蘖末期、孕穗抽穗期和乳熟期,平均通量为5.7mg.m-2.h-1。在测定期内,CH4排放与5和10cm土壤温度呈显著正相关,与土壤Eh呈显著负相关,与土壤pH值、水层深浅相关不明显。  相似文献   
73.
Pectinase and cellulase, which are used to macerate plant material, always show traces of DNase activities that result in DNA nicking. Moreover, the DNA polymerase I usually applied in the in situ nick translation techniques shows both 5' to 3' and 3' to 5' exonuclease activities. As a result, significant nonspecific labeling appears in control preparations that are not digested by a restriction endonuclease. Our procedure includes blocking nonspecific nick labeling before incubation with restriction enzymes (HpaII and HaeIII). This is achieved by incorporation of ddGTP into DNA by the Taq polymerase which lacks 3' to 5' exonuclease activity. This method gives satisfactory results because it eliminates nonspecific nick translation signals that are present after applying the methods described for animal material.  相似文献   
74.

Background

The rapidly expanding availability of de novo sequencing technologies can greatly facilitate efforts to monitor the relatively high mutation rates of influenza A viruses and the detection of quasispecies. Both the mutation rates and the lineages of influenza A viruses are likely to play an important role in the natural history of these viruses and the emergence of phenotypically and antigenically distinct strains.

Methodology and Principal Findings

We evaluated quasispecies and mixed infections by de novo sequencing the whole genomes of 10 virus isolates, including eight avian influenza viruses grown in embryonated chicken eggs (six waterfowl isolates - five H3N2 and one H4N6; an H7N3 turkey isolate; and a bald eagle isolate with H1N1/H2N1 mixed infection), and two tissue cultured H3N2 swine influenza viruses. Two waterfowl cloacal swabs were included in the analysis. Full-length sequences of all segments were obtained with 20 to 787-X coverage for the ten viruses and one cloacal swab. The second cloacal swab yielded 15 influenza reads of ∼230 bases, sufficient for bioinformatic inference of mixed infections or quasispecies. Genomic subpopulations or quasispecies of viruses were identified in four egg grown avian influenza isolates and one cell cultured swine virus. A bald eagle isolate and the second cloacal swab showed evidence of mixed infections with two (H1 and H2) and three (H1, H3, and H4) HA subtypes, respectively. Multiple sequence differences were identified between cloacal swab and the virus recovered using embryonated chicken eggs.

Conclusions

We describe a new approach to comprehensively identify mixed infections and quasispecies in low passage influenza A isolates and cloacal swabs and add to the understanding of the ecology of influenza A virus populations.  相似文献   
75.
76.

Background

Children with neuromuscular disorders with a progressive muscle weakness such as Duchenne Muscular Dystrophy and Spinal Muscular Atrophy frequently develop a progressive scoliosis. A severe scoliosis compromises respiratory function and makes sitting more difficult. Spinal surgery is considered the primary treatment option for correcting severe scoliosis in neuromuscular disorders. Surgery in this population requires a multidisciplinary approach, careful planning, dedicated surgical procedures, and specialized after care.

Methods

The guideline is based on scientific evidence and expert opinions. A multidisciplinary working group representing experts from all relevant specialties performed the research. A literature search was conducted to collect scientific evidence in answer to specific questions posed by the working group. Literature was classified according to the level of evidence.

Results

For most aspects of the treatment scientific evidence is scarce and only low level cohort studies were found. Nevertheless, a high degree of consensus was reached about the management of patients with scoliosis in neuromuscular disorders. This was translated into a set of recommendations, which are now officially accepted as a general guideline in the Netherlands.

Conclusion

In order to optimize the treatment for scoliosis in neuromuscular disorders a Dutch guideline has been composed. This evidence-based, multidisciplinary guideline addresses conservative treatment, the preoperative, perioperative, and postoperative care of scoliosis in neuromuscular disorders.  相似文献   
77.

Introduction  

The aim of our study was to investigate the association between arthritic disease activity and antibodies to mutated citrullinated vimentin (anti-MCV), because such a relation has been suggested.  相似文献   
78.
Objectives: The aim of this study was to assess persistence and tissue invasion of Candida albicans strains isolated from a 65 year‐old patient with chronic hyperplastic candidosis (CHC), that subsequently developed into squamous cell carcinoma (SCC). Materials and Methods: C. albicans (n=7) were recovered from the oral cavity of the patient over seven years. Confirmation of CHC and SCC in this patient was achieved by histopathological examination of incisional biopsy tissue. DNA fingerprinting was performed on the seven isolates from the CHC patient together with a further eight isolates from patients with normal oral mucosa (n=2), chronic atrophic candidosis (n=1), SCC (n=1) and CHC (n=4). Genotyping involved the use of inter‐repeat PCR using the eukaryotic repeat primer 1251. Characterisation of the tissue invasive abilities of the isolates was achieved by infecting a commercially available reconstituted human oral epithelium (RHE; SkinEthic, Nice, France). After 24 h. C. albicans tissue invasion was assessed by histopathological examination. Results: DNA fingerprinting demonstrated strain persistence of C. albicans in the CHC patient over a seven year period despite provision of systemic antifungal therapy. The strain of C. albicans isolated from this patient was categorised as a high invader within the RHE compared to other isolates. Conclusions: Candidal strain persistence was evident in a patient with CHC over seven years. This persistence may be due to incomplete eradication from the oral cavity following antifungal therapy or subsequent recolonisation from other body sites or separate exogenous sources. The demonstration of enhanced in vitro tissue invasion by this particular strain may, in part, explain the progression to carcinoma.  相似文献   
79.
Asif  MJ  Mak  C  Othman  RY 《Plant Cell, Tissue and Organ Culture》2001,67(3):267-270
In vitro zygotic embryo culture of wild banana significantly increased the germination compared to greenhouse grown seeds. Embryo orientation and BAP concentration significantly affected germination rate. These factors together with gelling agent, dark and light conditions and coconut water, also showed variable effects on the number of roots per plant, root length, shoot length, number of days to root emergence and number of days to shoot emergence.  相似文献   
80.
An NSO/GS cell line secreting a humanized antibody was routinely propagated in a T-flask using 2% serum. For scale-up of antibody production, this cell line was inoculated into a hollow fiber system using the same serum concentration. The metabolic activity increased for a few days in the hollow fiber system, but invariably the activity dropped dramatically as the cells died by day 7. A hollow fiber micro-bioreactor was used as a screening tool to examine possible reasons for cell death in the large-scale system. As seen in the hollow fiber system, cells died when 2% serum was used either on the cell side only or on both sides of the fiber in the micro-bioreactor. In contrast, the use of 20% serum on the cell side of the fiber and basal medium on the non-cell side resulted in good cell expansion at high viability. Regardless of the cell side serum concentration, no further growth enhancements were seen when up to 20% serum was placed on the non-cell side of the fiber. These results suggest that a serum component that does not readily cross the fiber is limiting cell growth in the hollow fiber bioreactors. The addition of a cholesterol-rich lipid supplement resulted in better cell growth in the micro-bioreactor, while the addition of other non-cholesterol lipid supplements resulted in no growth enhancement. The growth-enhancing properties of the cholesterol supplement were more pronounced at lower serum concentrations, suggesting that poor growth at low serum concentration was due to suboptimal cholesterol levels. When the cell side serum concentration was increased to 20% in the hollow fiber system, cells grew and filled the bioreactor, allowing a 39-day production run. These results demonstrate that this NSO cell line requires an increased cell side serum concentration for optimal growth and that this requirement is likely due to the inherent cholesterol dependency of this cell line.  相似文献   
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