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Proliferation, migration, and invasiveness of the normal placental extravillous trophoblast (EVT) cells are negatively regulated by transforming growth factor-beta (TGF-beta), whereas malignant EVT (JAR and JEG-3 choriocarcinoma) cells are resistant to TGF-beta. These malignant cells were found to have lost the expression of Smad3. Present study examined whether Smad3 restitution in JAR cells could restore TGF-beta response. We produced a stable Smad3 cDNA-transfected clone (JAR-smad3/c) which exhibited further upregulation of Smad3 in the presence of TGF-beta1. Since anti-invasive effects of TGF-beta in the normal EVT cells were shown to be mediated in part by plasminogen activator inhibitor-1 (PAI-1) and urokinase-type plasminogen activator (uPA), we compared the expression of PAI-1 and uPA in the normal EVT, JAR, and JAR-smad3/c cells in the presence or absence of TGF-beta1. The basal levels of PAI-1 mRNA and secreted PAI-1 and uPA proteins were found to be very low in JAR and JAR-smad3/c cells, as compared to the normal EVT cells. However, TGF-beta1 upregulated PAI-1 and downregulated uPA in JAR-smad3/c cells, but not in JAR cells. Thus, resistance of choriocarcinoma cells to anti-invasive effects of TGF-beta may, at least in part, be due to loss of Smad3 expression.  相似文献   
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This study examined the effects of a 15-day cessation of training on maximal oxygen consumption and selected physiological variables (maximal heart rate, cardiac output [Q], stroke volume [SV], arteriovenous oxygen difference [(a-v)O2 diff], blood plasma concentration) in 15 women middle-distance competitive runners (.VO2max: 49.8 +/- 1.1 ml.kg(-1).min(-1)). Subjects were randomly assigned to a cessation training (CT, n = 7) or maintenance training (MT, n = 8) group and tested every 5 days. Q was measured by CO2 rebreathing from which SV and (a-v)O2 diff were calculated. No significant changes were found at day 5. After 10 days there was a significant decrement in .VO2max (3.8 ml.kg(-1).min(-1)) in the CT group, being significantly lower than MT but no changes thereafter in any physiological variables. Performance (2,400 m) times did not change for MT but was significantly slower (21.5 +/- 7.1 seconds) for the CT group after 15 days, corresponding to the 7.8% decrease in .VO2max. These findings suggest that in competitive women middle-distance runners, actual performance decrements found after 15 days of CT most likely are due to declines in .VO2max.  相似文献   
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Pseudomonas aeruginosa biofilm is commonly associated with chronic wound infection. A FDA approved wireless electroceutical dressing (WED), which in the presence of conductive wound exudate gets activated to generate electric field (0.3–0.9V), was investigated for its anti-biofilm properties. Growth of pathogenic P. aeruginosa strain PAO1 in LB media was markedly arrested in the presence of the WED. Scanning electron microscopy demonstrated that WED markedly disrupted biofilm integrity in a setting where silver dressing was ineffective. Biofilm thickness and number of live bacterial cells were decreased in the presence of WED. Quorum sensing genes lasR and rhlR and activity of electric field sensitive enzyme, glycerol-3-phosphate dehydrogenase was also repressed by WED. This work provides first electron paramagnetic resonance spectroscopy evidence demonstrating that WED serves as a spontaneous source of reactive oxygen species. Redox-sensitive multidrug efflux systems mexAB and mexEF were repressed by WED. Taken together, these observations provide first evidence supporting the anti-biofilm properties of WED.  相似文献   
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C1 inhibitor (C1IN) is a multi-facet serine protease inhibitor in the plasma cascades, inhibiting several proteases, notably, regulates both complement and contact system activation. Despite huge advancements in the understanding of C1IN based on biochemical properties and its roles in the plasma cascades, the phylogenetic history of C1IN remains uncharacterized. To date, there is no comprehensive study illustrating the phylogenetic history of C1IN. Herein, we explored phylogenetic history of C1IN gene in vertebrates. Fishes have C1IN with two immunoglobulin like domains attached in the N-terminal region. The RCL regions of CIIN from fishes and tetrapod genomes have variations at the positions P2 and P1′. Gene structures of C1IN gene from selected ray-finned fishes varied in the Ig domain region with creation of novel intron splitting exon Im2 into Im2a and Im2b. This intron is limited to ray-finned fishes with genome size reduced below 1 Gb. Hence, we suggest that genome compaction and associated double-strand break repairs are behind this intron gain. This study reveals the evolutionary history of C1IN and confirmed that this gene remains the same locus for ∼450 MY in 52 vertebrates analysed, but it is not found in frogs and lampreys.  相似文献   
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In India, about 0.86 million people is engaged in pulling cycle rickshaws as occupation. There is no anthropometric data of cycle rickshaw pullers although data is available for Indian population. The objective of the study was to collect anthropometric data of the cycle rickshaw pullers so that these could be utilized for redesigning a cycle rickshaw. Anthropometric data for 34 body measurements were recorded from 880 rickshaw pullers (age 18 to 66 years) of four different places in India. The mean values of different standing heights, different lengths and breadths of cycle rickshaw pullers were significantly lower compared with Indian population. However, there was no significant difference in erect sitting height. The outcome of the research project is beneficial for the manufacturers of cycle rickshaws and similar products well as users of such products, including rickshaw pullers. The manufacturers would be able to use the data for fabricating newer models of cycle rickshaws which would be more compatible for rickshaw pullers as well as passengers.  相似文献   
28.
Tocochromanols encompass a group of compounds with vitamin E activity essential for human nutrition. Structurally, natural vitamin E includes eight chemically distinct molecules: -, β-, γ- and δ-tocopherol; and -, β-, γ- and δ-tocotrienol. Symptoms caused by -tocopherol deficiency can be alleviated by tocotrienols. Thus, tocotrienols may be viewed as being members of the natural vitamin E family not only structurally but also functionally. Palm oil and rice bran oil represent two major nutritional sources of natural tocotrienol. Taken orally, tocotrienols are bioavailable to all vital organs. The tocotrienol forms of natural vitamin E possesses powerful hypocholesterolemic, anti-cancer and neuroprotective properties that are often not exhibited by tocopherols. Oral tocotrienol protects against stroke-associated brain damage in vivo. Disappointments with outcomes-based clinical studies testing the efficacy of -tocopherol need to be handled with caution and prudence recognizing the untapped opportunities offered by the other forms of natural vitamin E. Although tocotrienols represent half of the natural vitamin E family, work on tocotrienols account for roughly 1% of the total literature on vitamin E. The current state of knowledge warrants strategic investment into investigating the lesser known forms of vitamin E.  相似文献   
29.
Tripathi R  Mishra D  Rizvi A  Singh C 《Life sciences》2007,81(21-22):1544-1548
In our search for synthetic substitutes for artemisinin and its derivatives we had earlier prepared a series of adamantane-based 1, 2, 4-trioxanes 5a-c which had shown promising activity against P. berghei in Swiss mice. We have further evaluated these and two new compounds (5d-e) against Plasmodium knowlesi W1, a virulent malaria parasite in rhesus monkeys, in the dose range of 40-80 mg/kg x 5 days by intramuscular route. Trioxanes 5b and 5c showed 100% protection and cure at 80 mg/kg x 5 days, while trioxane 5a showed 71% cure at this dose. Detailed studies again showed 50% curative effect of 5a at 40 mg/kg x 5 days treatment.  相似文献   
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