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91.
Apoptosis of skeletal muscle fibers is a well-known event occurring in patients suffering from muscular dystrophies. In this study, we hypothesized that functional polymorphisms in genes involved in the mitochondrial apoptotic pathway might modulate the apoptotic capacity underlying the muscle loss and contributing to intrafamilial and interfamilial variable phenotypes in LGMD2C (Limb Girdle Muscular Dystrophy type 2C) patients sharing the same c.521delT mutation in SGCG gene. Detection of apoptosis was confirmed on muscle biopsies taken from LGMD2C patients using the TUNEL method. We genotyped then ten potentially functional SNPs in TP53, BCL-2 and BAX genes involved in the mitochondrial apoptotic pathway. Potential genotype-dependent Bcl-2 and p53 protein expressed in skeletal muscle was investigated using western blot and ELISA assays. The result showed that muscle cells carrying the TP53-R72R and TP53-16?bp del/del genotypes displayed an increased p53 level which could be more effective in inducing apoptosis by activation of the pro-apoptotic gene expression. In addition, the BCL2-938 AA genotype was associated with increased Bcl-2 protein expression in muscle from LGMD2C patients compared to -938CC genotype, while there was no evidence of significant difference in the BAX haplotype. Our findings suggest that increased Bcl-2 protein expression may counteract pro-apoptotic pathways and thus reduce the muscle loss. To the best of our knowledge, this is a pioneer study evaluating the role of apoptotic BCL-2 and TP53 genes in contributing to the phenotypic manifestation of c.521delT mutation in LGMD2C patients. Larger studies are needed to validate these findings.  相似文献   
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Background

Given the high occurrence of prostate cancer worldwide and one of the major sources of the discovery of new lead molecules being medicinal plants, this research undertook to investigate the possible anti-cancer activity of two natural cycloartanes; cycloartane-3,24,25-diol (extracted in our lab from Tillandsia recurvata) and cycloartane-3,24,25-triol (purchased). The inhibition of MRCKα kinase has emerged as a potential solution to restoring the tight regulation of normal cellular growth, the loss of which leads to cancer cell formation.

Methods

Kinase inhibition was investigated using competition binding (to the ATP sites) assays which have been previously established and authenticated and cell proliferation was measured using the WST-1 assay.

Results

Cycloartane-3,24,25-triol demonstrated strong selectivity towards the MRCKα kinase with a Kd50 of 0.26 μM from a total of 451 kinases investigated. Cycloartane-3,24,25-triol reduced the viability of PC-3 and DU145 cell lines with IC50 values of 2.226?±?0.28 μM and 1.67?±?0.18 μM respectively.

Conclusions

These results will prove useful in drug discovery as Cycloartane-3,24,25-triol has shown potential for development as an anti-cancer agent against prostate cancer.  相似文献   
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Effective herbicide resistance management requires an assessment of the range of spatial dispersion of resistance genes among weed populations and identification of the vectors of this dispersion. In the grass weed Alopecurus myosuroides (black-grass), seven alleles of the acetyl-CoA carboxylase (ACCase) gene are known to confer herbicide resistance. Here, we assessed their respective frequencies and spatial distribution on two nested geographical scales (the whole of France and the French administrative district of C?te d'Or) by genotyping 13 151 plants originating from 243 fields. Genetic variation in ACCase was structured in local populations at both geographical scales. No spatial structure in the distribution of resistant ACCase alleles and no isolation by distance were detected at either geographical scale investigated. These data, together with ACCase sequencing and data from the literature, suggest that evolution of A. myosuroides resistance to herbicides occurred at the level of the field or group of adjacent fields by multiple, independent appearances of mutant ACCase alleles that seem to have rather restricted spatial propagation. Seed transportation by farm machinery seems the most likely vector for resistance gene dispersal in A. myosuroides.  相似文献   
95.
Cuttlefish powder (CFP) from Sepia officinalis by-products was prepared and tested as a fermentation substrate for microbial growth and protease production by several species of bacteria: Bacillus licheniformis, Bacillus subtilis, Pseudomonas aeruginosa, Bacillus cereus BG1, and Vibrio parahaemolyticus. All microorganisms studied grew well and produced protease activity when cultivated in medium containing only CFP indicating that the strains can obtain their carbon and nitrogen source requirements directly from whole by-product proteins. Moreover, it was found that the addition to the cuttlefish medium of diluted fishery wastewaters (FWW), generated by marine-products processing factories, enhanced the production of protease. Maximum activity was obtained when cells were grown in cuttlefish media containing 5-times or 10-times diluted FWW. Five-times diluted FWW enhanced protease production by B. cereus BG1 and B. subtilis by 467% and 75% more than control media, respectively. The enhancement could have been due to the high organic content or high salts in FWW.As a result, cuttlefish by-products powder enriched with diluted FWW was found to be a suitable growth media for protease-producing strains. This new process, which converts underutilized wastes (liquid and solid) into more marketable and acceptable forms, coupled with protease production, can be an alternative way to the biological treatment of solid and liquid wastes generated by the cuttlefish processing industry.  相似文献   
96.
Potato is the world's fourth largest food crop yet it continues to endure late blight, a devastating disease caused by the Irish famine pathogen Phytophthora infestans. Breeding broad-spectrum disease resistance (R) genes into potato (Solanum tuberosum) is the best strategy for genetically managing late blight but current approaches are slow and inefficient. We used a repertoire of effector genes predicted computationally from the P. infestans genome to accelerate the identification, functional characterization, and cloning of potentially broad-spectrum R genes. An initial set of 54 effectors containing a signal peptide and a RXLR motif was profiled for activation of innate immunity (avirulence or Avr activity) on wild Solanum species and tentative Avr candidates were identified. The RXLR effector family IpiO induced hypersensitive responses (HR) in S. stoloniferum, S. papita and the more distantly related S. bulbocastanum, the source of the R gene Rpi-blb1. Genetic studies with S. stoloniferum showed cosegregation of resistance to P. infestans and response to IpiO. Transient co-expression of IpiO with Rpi-blb1 in a heterologous Nicotiana benthamiana system identified IpiO as Avr-blb1. A candidate gene approach led to the rapid cloning of S. stoloniferum Rpi-sto1 and S. papita Rpi-pta1, which are functionally equivalent to Rpi-blb1. Our findings indicate that effector genomics enables discovery and functional profiling of late blight R genes and Avr genes at an unprecedented rate and promises to accelerate the engineering of late blight resistant potato varieties.  相似文献   
97.
Sleep and Biological Rhythms - The aim of this cross-sectional study was to determine the prevalence, risk factors, other associated sleep disorders and commodities of Restless Legs Syndrome (RLS)...  相似文献   
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