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51.
We aimed to review and meta-analyze the inflammatory and oxidative factors following alpha lipoic acid (ALA) and its derivative “andrographolid-lipoic acid-1” (AL-1) in ulcerative colitis (UC). ALA plays an important role in scavenging intracellular radicals and inflammatory elements. AL-1 is found in herbal medicines with potent anti-inflammatory properties. Data were collected from the Google Scholar, PubMed, Scopus, Evidence-based medicine/clinical trials, and Cochrane library database until 2017, which finally resulted in 22 animal studies (70 rats and 162 mice). The beneficial effects of ALA or AL-1 on the most important parameters of UC were reviewed; also, studies were considered separately in mice and rats. Administration of ALA and AL-1 significantly reduced the tumor necrosis factor-α level compared with the controls, while data were not noteworthy in the meta-analysis (mean differences = −18.57 [95% CI = −42.65 to 5.51], P = 0.13). In spite of insignificant decrease in meta-analysis outcomes (differences = 6.92 [95% CI = −39.33 to 53.16], P = 0.77), a significant reduction in myeloperoxidase activity was shown following ALA or AL-1 treatment compared with the controls. Despite significant differences in each study, we had to exclude some studies to homogenize data for meta-analyzing as they showed insignificant results. Interleukin 6, cyclooxygenase-2, glutathione, malondialdehyde, superoxide dismutase, histopathological score, macroscopic and microscopic scores, disease activity index, body weight change, and colon length were also reviewed. Most studies have emphasized on significant positive effects of ALA and AL-1. Comprehensive clinical trials are obligatory to determine the precious position of ALA or AL-1 in the management of UC.  相似文献   
52.
53.
Fifteen Cases of Penicilliosis in Guangdong,China   总被引:7,自引:0,他引:7  
We analyzed the occurrence, clinical and physical features, laboratory findings, diagnostic criteria, reaction to therapy and prognosis of 15 cases Penecilliosis marneffei. Four were localized infection on skin, eleven were systemic infection, all cases were found in Guangdong province of China. We found that males were predominant in infection compared with females in 15 patients, and all patients observed had different occupations. The patients with AIDS as underlying disease were commonly drivers or unemployed. Thirteen of 15 patients had underlying diseases, i.e., connective tissue disease, aplastic anemia, kidney transplant, AIDS. Clinical features showed different symptoms, including weight loss, high fever, skin lesions, and respiratory system symptoms. Seven of 15 patients received antifungal therapy, the remaining eight patients did not receive therapy for different reasons. Nine of the patients died five recovered. Fifteen isolates were cultured from skin lesions, blood, bone marrow, peritoneum dialysis and pleural effusion and were confirmed to be Penicillium marneffei by morphology, thermal dimorphism, pathology and DNA sequence analysis. This report indicates that Penicillium marneffei may exist in nature in Guangdong province of SE China.  相似文献   
54.
Strategies for microsatellite isolation: a review   总被引:75,自引:0,他引:75  
In the last few years microsatellites have become one of the most popular molecular markers used with applications in many different fields. High polymorphism and the relative ease of scoring represent the two major features that make microsatellites of large interest for many genetic studies. The major drawback of microsatellites is that they need to be isolated de novo from species that are being examined for the first time. The aim of the present paper is to review the various methods of microsatellite isolation described in the literature with the purpose of providing useful guidelines in making appropriate choices among the large number of currently available options. In addition, we propose a fast and easy protocol which is a combination of different published methods.  相似文献   
55.
Refsum's disease (hereditary motor sensory neuropathy type IV, heredopathia atactica polyneuritiformis) is an autosomal recessive disorder the clinical features of which include retinitis pigmentosa, blindness, anosmia, deafness, sensory neuropathy, ataxia and accumulation of phytanic acid in plasma- and lipid-containing tissues. The transport and biochemical pathways of phytanic acid metabolism have recently been defined with the cloning of two key enzymes, phytanoyl-CoA 2-hydroxylase (PAHX) and 2-hydroxyphytanoyl-CoA lyase, together with the confirmation of their localization in peroxisomes. PAHX, an iron(II) and 2-oxoglutarate-dependent oxygenase is located on chromosome 10p13. Mutant forms of PAHX have been shown to be responsible for some, but not all, cases of Refsum's disease. Certain cases have been shown to be atypical mild variants of rhizomelic chondrodysplasia punctata type 1a. Other atypical cases with low-plasma phytanic acid may be caused by alpha-methylacyl-CoA racemase deficiency. A sterol-carrier protein-2 (SCP-2) knockout mouse model shares a similar clinical phenotype to Refsum's disease, but no mutations in SCP-2 have been described to-date in man. This review describes the clinical, biochemical and metabolic features of Refsum's disease and shows how the biochemistry of the alpha-oxidation pathway may be linked to the regulation of metabolic pathways controlled by isoprenoid lipids, involving calcineurin or the peroxisomal proliferator activating alpha-receptor.  相似文献   
56.
Some recent applications of stereoselective chromatography in the fields of clinical pharmacy, drug analysis, food, and natural products are reviewed. The review is documented with up-to-date literature, which will assist further expansion of research in these areas.  相似文献   
57.
A call to fins! Zebrafish as a gerontological model   总被引:1,自引:0,他引:1  
Gerhard GS  Cheng KC 《Aging cell》2002,1(2):104-111
Among the wide variety of model organisms commonly used for studies on aging, such as worms, flies and rodents, a wide research gap exists between the invertebrate and vertebrate model systems. In developmental biology, a similar gap has been filled by the zebrafish (Danio rerio). We propose that the zebrafish is uniquely suited to serve as a bridge model for gerontology. With high fecundity and economical husbandry requirements, large populations of zebrafish may be generated quickly and cheaply, facilitating large-scale approaches including demographic studies and mutagenesis screens. A variety of mutants identified in such screens have led to modelling of human disease, including cardiac disorders and cancer. While zebrafish longevity is at least 50% longer than in commonly used mouse strains, as an ectothermic fish species, its life span may be readily modulated by caloric intake, ambient temperature and reproductive activity. These features, coupled with a growing abundance of biological resources, including an ongoing genome sequencing project, make the zebrafish a compelling model organism for studies on aging.  相似文献   
58.
Exocytosis is, in all likelihood, an important communication method among microbes. Ciliates are highly differentiated and specialized micro-organisms for which versatile and/or sophisticated exocytotic organelles may represent important adaptive tools. Thus, in ciliates, we find a broad range of different extrusomes, i.e ejectable membrane-bound organelles. Structurally simple extrusomes, like mucocysts and cortical granules, are widespread in different taxa within the phylum. They play the roles in each case required for the ecological needs of the organisms. Then, we find a number of more elaborate extrusomes, whose distribution within the phylum is more limited, and in some way related to phylogenetic affinities. Herein we provide a survey of literature and our data on selected extrusomes in ciliates. Their morphology, distribution, and possible function are discussed. The possible phylogenetic implications of their diversity are considered.  相似文献   
59.
Pasteuria penetrans is a mycelial, endospore-forming, bacterial parasite that has shown great potential as a biological control agent of root-knot nematodes. Considerable progress has been made during the last 10 years in understanding its biology and importance as an agent capable of effectively suppressing root-knot nematodes in field soil. The objective of this review is to summarize the current knowledge of the biology, ecology, and biological control potential of P. penetrans and other Pasteuria members. Pasteuria spp. are distributed worldwide and have been reported from 323 nematode species belonging to 116 genera of free-living, predatory, plant-parasitic, and entomopathogenic nematodes. Artificial cultivation of P. penetrans has met with limited success; large-scale production of endospores depends on in vivo cultivation. Temperature affects endospore attachment, germination, pathogenesis, and completion of the life cycle in the nematode pseudocoelom. The biological control potential of Pasteuria spp. have been demonstrated on 20 crops; host nematodes include Belonolaimus longicaudatus, Heterodera spp., Meloidogyne spp., and Xiphinema diversicaudatum. Pasteuria penetrans plays an important role in some suppressive soils. The efficacy of the bacterium as a biological control agent has been examined. Approximately 100,000 endospores/g of soil provided immediate control of the peanut root-knot nematode, whereas 1,000 and 5,000 endospores/g of soil each amplified in the host nematode and became suppressive after 3 years.  相似文献   
60.
Mammalian cell retention devices for stirred perfusion bioreactors   总被引:4,自引:1,他引:3  
Within the spectrum of current applications for cell culture technologies, efficient large-scale mammalian cell production processes are typically carried out in stirred fed-batch or perfusion bioreactors. The specific aspects of each individual process that can be considered when determining the method of choice are presented. A major challenge for perfusion reactor design and operation is the reliability of the cell retention device. Current retention systems include cross-flow membrane filters, spin-filters, inclined settlers, continuous centrifuges and ultrasonic separators. The relative merits and limitations of these technologies for cell retention and their suitability for large-scale perfusion are discussed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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