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261.
Alpha-1-antitrypsin (AAT) plays an important role in the pathogenesis of emphysema, the pathological lesion underlying the majority of the manifestations of Chronic Obstructive Pulmonary Disease (COPD). In this study we tested the hypothesis that common AAT polymorphisms influence the risk of developing COPDs. We investigated PiM1 (Ala213Val), PiM2 (Arg101His), PiM3 (Glu376Asp), PiS (Glu264Val) and PiZ (Glu342Lys) SERPINA1 alleles in 100 COPD patients and 200 healthy controls. No significant differences were observed in allele frequencies between COPD patients and controls, neither did haplotype analysis show significant differences between the two groups. A cross-sectional study revealed no significant relationship between common SERPINA1 polymorphisms (PiM1, PiM2, PiM3) and the emphysematous type of COPD. In addition, FEV(1) annual decline, determined during a two-year follow up period, revealed no difference among carriers of the tested polymorphisms.  相似文献   
262.
This work deals with the synthesis of a new nitrogen mustard derivative based on thymine. To introduce the bis(2-chloroethyl)amine group to position 4 of the pyrimidine base, many strategies were explored and the desired compound was finally obtained, thanks to a synthetic pathway in five steps.  相似文献   
263.
Artemia has a remarkable genetic variability that can be expressed in various phenotypic characteristics, such as morphometry, growth rate, reproductive isolation or molecular composition. This study presents reproduction characteristics, survival rate and sex-ratio of four Artemia salina populations from Tunisia cultured under standard conditions. Results show that both low (17.8% and 30.6% in Megrine saltwork and Sabkhet Sijoumi, respectively) and high (83.9% for Sahline saltwork) values were recorded for the percentage of total oviparous offspring. The offspring per brood varied from 70.3?±?41.9 (Megrine saltwork) to 73.6?±?51.4 (Sabkhet El Adhibet). Broods per female varied between 3.1?±?0.9 (Sahline saltwork) and 4.5?±?1.2 (Megrine saltwork), and time between broods ranged from 5.7?±?1.1 to 6.5?±?2.2 days for Megrine and Sahline, respectively. Statistical analysis (one-way analysis of variance, Tukey's HSD test, p?<?0.05) revealed no significant differences between reproductive traits of the four studied populations except for mean of oviparous and oviviparous offspring per female (F?=?9.158, p?<?0.05), and brood per female (F?=?4.779, p?<?0.05). The survival rate of the four studied A. salina populations fluctuated between 31.4% and 64.5% for Megrine and Sahline saltwork, respectively. However, the sex-ratio showed that for Megrine saltwork and Sabkhet El Adhibet, males predominated with 1?:?0.90 and 1?:?0.97 (males?:?females), respectively. The comparison between our results and those reported of other Artemia populations showed that the offspring per brood of Tunisian Artemia are comparable to A. persimilis but different to A. salina from Abu Kammash (Libya) and A. urmiana (Urmia Lake, Iran), and that days between brood, are similar to A. salina from Abu Kammash, A. sinica and polyploid A. parthenogenetica, but different from A. persimilis and A. franciscana.  相似文献   
264.
The Alternative Reading Frame (ARF) protein suppresses tumorigenesis through p53-dependent and p53-independent pathways. Most of ARF's anti-proliferative activity is conferred by sequences in its first exon. Previous work showed specific amino acid changes occurred in that region during primate evolution, so we programmed those changes into human p14ARF to assay their functional impact. Two human p14ARF residues (Ala14 and Thr31) were found to destabilize the protein while two others (Val24 and Ala41) promoted more efficient p53 stabilization and activation. Despite those effects, all modified p14ARF forms displayed robust p53-dependent anti-proliferative activity demonstrating there are no significant biological differences in p53-mediated growth suppression associated with simian versus human p14ARF residues. In contrast, p53-independent p14ARF function was considerably altered by several residue changes. Val24 was required for p53-independent growth suppression whereas multiple residues (Val24, Thr31, Ala41 and His60) enabled p14ARF to block or reverse the inherent chromosomal instability of p53-null MEFs. Together, these data pinpoint specific residues outside of established p14ARF functional domains that influence its expression and signaling activities. Most intriguingly, this work reveals a novel and direct role for p14ARF in the p53-independent maintenance of genomic stability.  相似文献   
265.
Abstract

The present work aims to investigate the attractive ability of the newly isolated bacterium Serratia plymuthica BMA1, to release phosphorus (P) from rock phosphate (RP) and also to assess its beneficial effect in promoting the growth of Vicia faba. This strain exhibited the highest RP-solubilization activity ever reported, with 450?mg l?1 of soluble P at 30?°C. At 10 and 20?°C, its RP-solubilization was estimated at 100 and 200?mg l?1, respectively. HPLC analysis revealed that RP-solubilizing activity was associated with the release of gluconic acid. The hydroxyapatite (HA) solubilization activity concomitantly occurred with the secretion of gluconic acid and lactic acid. Under greenhouse conditions, application of BMA1 strain as an inoculant in presence of RP as the sole P source, considerably increased phosphorus uptake by V. faba L. and upgraded its overall growth in terms of dry weight and length by 76% and 39%, respectively. This growth promoting effect was accompanied by a substantial increase in chlorophyll contents. Additionally, phosphorus levels within roots and shoots of S. plymuthica BMA1-treated plants were approximately three times greater, compared to the non-inoculated control plants. When HA was used instead of RP, bacterization with BMA1 strain also enhanced the plant growth parameters and P contents, but significantly less than RP. These findings revealed that S. plymuthica BMA1 could be a potential candidate to improve the agronomic effectiveness of RP, toward a clean P-nutrition through the formulation of bio-phosphate fertilizers for plant growth promotion.  相似文献   
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