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81.
82.
Musilová E Fernandes V Silva NM Soares P Alshamali F Harich N Cherni L Gaaied AB Al-Meeri A Pereira L Cerný V 《American journal of physical anthropology》2011,145(4):592-598
Archaeological studies have revealed cultural connections between the two sides of the Red Sea dating to prehistory. The issue has still not been properly addressed, however, by archaeogenetics. We focus our attention here on the mitochondrial haplogroup HV1 that is present in both the Arabian Peninsula and East Africa. The internal variation of 38 complete mitochondrial DNA sequences (20 of them presented here for the first time) affiliated into this haplogroup testify to its emergence during the late glacial maximum, most probably in the Near East, with subsequent dispersion via population expansions when climatic conditions improved. Detailed phylogeography of HV1 sequences shows that more recent demographic upheavals likely contributed to their spread from West Arabia to East Africa, a finding concordant with archaeological records suggesting intensive maritime trade in the Red Sea from the sixth millennium BC onwards. Closer genetic exchanges are apparent between the Horn of Africa and Yemen, while Egyptian HV1 haplotypes seem to be more similar to the Near Eastern ones. 相似文献
83.
Ammar el-SM Said SA Suddek GM El-Damarawy SL 《Canadian journal of physiology and pharmacology》2011,89(4):269-276
The therapeutic usefulness of doxorubicin (Dox), an anthracycline antibiotic used as an anticancer agent, is limited by its cardiotoxicity. Dox-induced cardiotoxicity is mainly attributed to accumulation of reactive oxygen species and interaction of Dox with cellular iron metabolism. The present study investigated the effects of the iron chelator deferiprone (Def) against Dox-induced cardiotoxicity in rats. Dox (15?mg/kg) was injected intraperitoneally as a single dose, and Def (10?mg/kg) was administered orally for 10?days. Dox showed cardiotoxicity as evidenced by increased heart rate, elevated ST segment, prolonged QTc interval, and increased T wave amplitude. In addition, Dox enhanced aconitine cardiotoxicity by decreasing its dose, producing ventricular tachycardia. Administration of Def significantly attenuated Dox-induced electrocardiographic changes. Cardiotoxicity of Dox was confirmed biochemically by a significant elevation in serum creatine kinase-MB and lactate dehydrogenase activities as well as by myocardial malondialdehyde and reduced glutathione contents. Moreover, Dox caused a significant decrease in myocardial superoxide dismutase activity. Administration of Def significantly attenuated the biochemical changes. These results suggest that Def might be a potential cardioprotective agent against Dox-induced cardiotoxicity. 相似文献
84.
Ebrahim AM Eltayeb M Benker B Grill P Attahir M Osman A Elsadig M Michalke B 《Biological trace element research》2011,144(1-3):225-233
This study was performed to investigate trace elements and arsenic contents among Sudanese inhabitants living in the north, east, and west of Sudan. Inductively coupled plasma atomic emission spectrometry was used to determine the contents of Zn and Cu. Graphite furnace atomic absorption spectrometry was used to determine Se in serum samples. It was found that Se and Cu are in the normal range. Zinc showed discrepancies among all studied groups. Acute Zn deficiency was detected in the northern and eastern regions of Sudan. Inductively coupled plasma mass spectroscopy was operated in the dynamic reaction cell mode to determine the arsenic content in the nail samples of the northern inhabitants of Sudan. High values of arsenic were found in the northern people compared with the control group. This elevation could be linked to the misuse of insecticides and herbicides which might be associated with the high rate of cancer incidence in this region. 相似文献
85.
The aim of this study was to assess the impact of inoculation of Phaseolus vulgaris with two indigenous rhizobia strains on plant growth promotion, nitrogen turnover processes, richness and structure of the Rhizobiaceae and total bacterial communities in the bulk soil. Both strains used induced a significant increase in nodulation and grain yield. Analysis of bulk soil fertility showed positive, negative and strain-dependent effects of inoculation on nitrate, phosphorus and ammonium, respectively. Terminal-restriction fragment length polymorphism profiling demonstrated that inoculation significantly increased the phylotype richness of the bacterial communities. No significant difference in richness between the strains used and no additive effect of co-inoculation were observed. However, differences between both inoculants and a clear additive effect of co-inoculation on heterogeneity were found. This work gives original insights into the effect of rhizobial inoculation outside the restricted rhizospheric area. Effects on bacterial structure and diversity are clearly sensed in the neighbourhood of 25 cm and in a limited time course. Both Alpha- and Gammaproteobacteria, together with Firmicutes and Actinobacteria, were enhanced by inoculation, No evidence of terminal-restriction fragment inhibition was found. However, it remains to be answered how the impact on taxonomic groups can be related to effects on functional capabilities of soil microbial communities. 相似文献
86.
Gamma proteobacteria can nodulate legumes of the genus Hedysarum 总被引:1,自引:0,他引:1
Benhizia Y Benhizia H Benguedouar A Muresu R Giacomini A Squartini A 《Systematic and applied microbiology》2004,27(4):462-468
The bacteria hosted in the root nodules of the three Mediterranean wild legume species Hedysarum carnosum, Hedysarum spinosissimum subsp. capitatum, and Hedysarum pallidum, growing in native stands in different habitats in Algeria were isolated. Bacteria were recovered on yeast-mannitol-agar or on minimal media from a total of 52 nodules. Isolates were analyzed by Amplified Ribosomal DNA Restriction Analysis (ARDRA) using the enzyme CfoI, and further sorted by RAPD fingerprinting. A total of ten different types were found and their amplified 16S rDNA was sequenced and compared to databases. The BLAST alignment indicates that all the species whose sequences share 98 to 100% identity to the bacteria found in these nodules belong to the class Gammaproteobacteria and include Pantoea agglomerans, Enterobacter kobei, Enterobacter cloacae, Leclercia adecarboxylata, Escherichia vulneris, and Pseudomonas sp. No evidence of any rhizobial-like sequence was found even upon amplifying from the bulk of microbial cells obtained from the squashed nodules, suggesting that the exclusive occupants of the nodules formed by the three plants tested are members of the orders Enterobacteriales or Pseudomonadales. This is the first report of Gammaproteobacteria associated with legume nodules. Despite the presence of the related crop plant Hedysarum coronarium, specifically nodulated by Rhizobium sullae, these three Hedysarum species demonstrate to have undergone a separate path in terms of endophytic interactions with bacteria. An hypothesis to account for differences between the symbiotic relationships engaged by man-managed legumes, and those found in plants whose ecology is independent from human action, is discussed. 相似文献
87.
Ehab Mohamed Ammar Ying Jin Zhongqiang Wang Shang-Tian Yang 《Applied microbiology and biotechnology》2014,98(18):7761-7772
Propionic acid is currently produced mainly via petrochemicals, but there is increasing interest in its fermentative production from renewable biomass. However, the current propionic acid fermentation process suffers from low product yield and productivity. In this work, the gene encoding phosphoenolpyruvate carboxylase (PPC) was cloned from Escherichia coli and expressed in Propionibacterium freudenreichii. PPC catalyzes the conversion of phosphoenolpyruvate to oxaloacetate with the fixation of one CO2. Its expression in P. freudenreichii showed profound effects on propionic acid fermentation. Compared to the wild type, the mutant expressing the ppc gene grew significantly faster, consumed more glycerol, and produced propionate to a higher final titer at a faster rate. The mutant also produced significantly more propionate from glucose under elevated CO2 partial pressure. These effects could be attributed to increased CO2 fixation and resulting changes in the flux distributions in the dicarboxylic acid pathway. 相似文献
88.
Bouchlaka Souissi Chiraz Ammar Myriam Zarra Ines Jordan Catherine Bouazizi Fatma Cheour Ilhem Tekaya Raoudha Zeglaoui Hela Fourati Hela Bouajina Elyes Doss Nejib Helms Cindy Elgaaied Amel Sellami Slaheddine 《Molecular biology reports》2014,41(6):4141-4146
A deletion of two genes from the late cornified envelope (LCE), LCE3B and LCE3C within epidermal differentiation complex on chromosome 1 was shown to be associated with both psoriasis and psoriatic arthritis (PsA) in several populations. To assess whether this deletion may contribute to the genetic predisposition to PsA in Tunisia, a total of 73 patients with PsA and 120 healthy matched controls were screened for the deletion, LCE3C_LCE3B-del, and its tag SNP, rs4112788. We also evaluated a possible relationship between PSORS1 and LCE3C_LCE3B-del through genotyping two proxy markers to HLA-C (rs12191877 and rs2073048). Our results did not provide evidence for association between the LCE3C_LCE3B-del nor the rs4112788 and the PsA. Similarly, no significant epistatic effect was observed. Our data suggest that The LCE deletion, previously identified in patients with psoriasis, is not of a major importance in the development of PsA in Tunisian patients supporting the current perception that different genetic risk factors contribute to skin and joint disease. However, these results need to be confirmed by additional large-scale studies of Tunisian PsA patients and controls. 相似文献
89.
Elizabeth D. Hutchins Glenn J. Markov Walter L. Eckalbar Rajani M. George Jesse M. King Minami A. Tokuyama Lauren A. Geiger Nataliya Emmert Michael J. Ammar April N. Allen Ashley L. Siniard Jason J. Corneveaux Rebecca E. Fisher Juli Wade Dale F. DeNardo J. Alan Rawls Matthew J. Huentelman Jeanne Wilson-Rawls Kenro Kusumi 《PloS one》2014,9(8)
90.
Ammar Khairullah Laura Cousino Klein Suzanne M. Ingle Margaret T. May Courtney A. Whetzel Elizabeth J. Susman Tomá? Paus 《PloS one》2014,9(9)