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121.
Summary In five families with idiopathic (hereditary) hemochromatosis, clinical and biochemical expression of the disease occurred in offspring of probands, suggesting an autosomal dominant mode of inheritance. However, HLA typing of subjects indicated that a homozygous-heterozygous mating almost certainly had occurred in four of the five families, resulting in homozygous offspring. Thus, in these families inheritance of the hemochromatosis trait was best explained in terms of an autosomal recessive or intermediate mode of inheritance. This study demonstrates the value of HLA typing in identifying homozygous-heterozygous matings in hemochromatosis families.  相似文献   
122.
Minute virus of mice (MVM) shows an oncotropic behavior reflected by its ability to amplify its genome more efficiently in a number of transformed versus normal cells. In vivo and in vitro studies revealed that the major effect of cell transformation on MVM DNA replication occurs at the level of double-stranded replicative-form amplification. In particular, resolution of MVM DNA concatemers into monomers was found to be highly sensitive to neoplastic transformation.  相似文献   
123.
Raza  Qasim  Riaz  Awais  Bashir  Khurram  Sabar  Muhammad 《Plant molecular biology》2020,104(1-2):97-112
Plant Molecular Biology - By integrating genetics and genomics data, reproductive tissues-specific and heat stress responsive 35 meta-QTLs and 45 candidate genes were identified, which could be...  相似文献   
124.
The use of primary somatic cells in nuclear transfer procedure has opened a new opportunity to manipulate domestic animal genomes via homologous recombination. To date, while a few loci have been targeted in somatic cells using similar enrichment strategies as those used in mouse ES cells, there have been problems of low efficiency, mixed targeted and non-targeted cells within a colony and difficulties in cloning the cell after targeting. Utilizing the hypoxanthine guanine phosphoribosyl transferase (HPRT) as a test locus, it was determined that while no targeted colonies were identified using a conventional targeting construct, an average of 1 per million targeted cells were identified when a nuclear localization signal (nls) was added to the construct. When the nls was combined with cell synchronization using a thymidine block, targeting efficiency increased 7-fold. Moreover, the number of random integrants decreased by over 54-fold resulting in a 1:3 targeted to random integration ratio. This method should facilitate the application of homologous recombination to primary somatic cells.  相似文献   
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The RANKL/OPG/RANK pathway is the key mediator of osteoclastogenesis. Mononuclear cells may be implicated in post-menopausal osteoporosis. The effect of estrogen or raloxifene on bone resorption and the expression of RANKL/OPG/RANK in peripheral blood mononuclear cells (PBMCs) was examined. Twenty-nine women with post-menopausal osteoporosis were treated with estrogen (HRT) or raloxifene for 12 months. Bone mineral density (BMD) was measured at baseline and at 12 months at the spine and hip. Serum C-terminal telopeptide (CTX) and OPG were measured at baseline and at 1, 3, 6 and 12 months. PBMCs were isolated from 17 women and changes in RANKL, OPG and RANK mRNA were determined. The effects of estrogen or raloxifene in PBMCs in vitro were also assessed. BMD increased following treatment (lumbar spine % change mean [S.E.M.]: 4.3% [0.9], p<0.001). Serum CTX decreased (6 months: -43.7% [6.0], p<0.0001). Serum OPG declined gradually (12 months: -26.4% [4.4], p<0.001). RANKL, OPG and RANK gene expression decreased (6 months: RANKL 50.0% [24.8] p<0.001, OPG: 21.7% [28] p<0.001, RANK: 76.6% [10.2] p=0.015). Changes in OPG mRNA correlated with changes in BMD (r=-0.53, p=0.027) and CTX (r=0.7, p=0.0044). Down-regulation in RANKL, OPG, RANK mRNA and reduction in bone resorption was also seen in vitro. These results suggest that the expression of RANKL/OPG/RANK in PBMCs are responsive to the slowing in bone turnover/remodeling associated with treatment with estrogen or raloxifene. Further confirmatory studies are needed.  相似文献   
127.
Succinic acid is an important platform chemical with a variety of applications. Model-guided metabolic engineering strategies in Escherichia coli for strain improvement to increase succinic acid production using glucose and glycerol remain largely unexplored. Herein, we report what are, to our knowledge, the first metabolic knockout of the atpE gene to have increased succinic acid production using both glucose and alternative glycerol carbon sources in E. coli. Guided by a genome-scale metabolic model, we engineered the E. coli host to enhance anaerobic production of succinic acid by deleting the atpE gene, thereby generating additional reducing equivalents by blocking H+ conduction across the mutant cell membrane. This strategy produced 1.58 and .49 g l?1 of succinic acid from glycerol and glucose substrate, respectively. This work further elucidates a model-guided and/or system-based metabolic engineering, involving only a single-gene deletion strategy for enhanced succinic acid production in E. coli.  相似文献   
128.
Blood samples were collected and follicle diameters were determined daily beginning on Day 12 (Day 0 = ovulation) in 35 interovulatory intervals (IOIs) in heifers. A minor follicular wave with maximal diameter (6.0 ± 0.3 mm) on Day −4 was detected in six of seven IOIs that were scanned for follicles 4 mm or greater. The number of IOIs with a CV-identified minor FSH surge toward the end of the IOI was greater (P < 0.03) in two-wave IOIs (10/17) than in three-wave IOIs (4/18). The 17 two-wave IOIs were used for study of the temporal relationships among preovulatory follicle, FSH, LH, and estradiol. Daily growth rate of the preovulatory follicle was maximum on Days −11 to −7, minimum (P < 0.05) on Days −7 to −4, and increased (resurged, P < 0.05) on Days −4 to −3. A transient increase in FSH was maximum on mean Day −4, and the peak of a minor FSH surge occurred on Day −4.5 ± 0.2. Concentration of LH and estradiol increased between Days −5 and −4. Results demonstrated resurgence of the preovulatory follicle apparently for the first time in any species. Resurgence seemed more related temporally to the minor FSH surge than to the LH increase, but further study is needed. Results supported the novel hypotheses that a minor FSH surge near the end of the IOI is temporally associated with (1) the emergence of a minor follicular wave and (2) the resurgence in growth rate of the preovulatory follicle.  相似文献   
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Metabolic syndrome is associated with disturbances in gut microbiota composition. We aimed to investigate the effect of Lactobacillus casei Shirota (LcS) on gut microbiota composition, gut barrier integrity, intestinal inflammation and serum bile acid profile in metabolic syndrome. In a single-centre, prospective, randomised controlled pilot study, 28 subjects with metabolic syndrome received either LcS for 12 weeks (n = 13) or no LcS (n = 15). Data were compared to healthy controls (n = 16). Gut microbiota composition was characterised from stool using 454 pyrosequencing of 16S rRNA genes. Serum bile acids were quantified by tandem mass spectrometry. Zonulin and calprotectin were measured in serum and stool by ELISA. Bacteroidetes/Firmicutes ratio was significantly higher in healthy controls compared to metabolic syndrome but was not influenced by LcS. LcS supplementation led to enrichment of Parabacteroides. Zonulin and calprotectin were increased in metabolic syndrome stool samples but not influenced by LcS supplementation. Serum bile acids were similar to controls and not influenced by LcS supplementation. Metabolic syndrome is associated with a higher Bacteroidetes/Firmicutes ratio and gut barrier dysfunction but LcS was not able to change this. LcS administration was associated with subtle microbiota changes at genus level.

Trial Registration

ClinicalTrials.gov NCT01182844  相似文献   
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