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91.
92.
Esmat M. Hegazi Maria A. Konstantopoulou Annette Herz Wedad E. Khafagi Essam Agamy Sania Showiel Atwa Atwa Gehan M. Abd El‐Aziz Safaa M. Abdel‐Rahman 《Insect Science》2011,18(5):565-574
Abstract Prays oleae Bern, (OM) and Palpita unionalis Hüb., (JM) are two of the most important pests in olive groves in Egypt. A 3‐year monitoring study using sex pheromone traps in semi‐arid and arid olive groves was performed. In the semi‐arid grove, flight pattern of the OM was the same as in other Mediterranean countries, but in dates concordating plant phenology. The moth completes three generations annually: the first flight is in March to April, the second is in May to June and the third occurs in August to October. In the arid olive grove, an interesting flight pattern was observed. First flight was always very close or overlapped with the second one with no male catches during August to October. However, eggs were present most of the season, indicating unusually high female presence and oviposition activity of the OM during the absence of males in the traps. Generally, moth densities were significantly lower in low fruiting years than in higher ones and were also lower in the arid olive grove than in the semi‐arid one. In contrast, JM males were present all season, exhibiting six to seven and three to four overlapping flight peaks in arid and semi‐arid olive groves, respectively. Moth densities were significantly higher in the arid olive grove than those in the semi‐arid one. This study shows that trapping location and fruit bearing year are characteristics that strongly affect the grove‐specific information needed to estimate correctly adult emergence and thus the timing of control measures. 相似文献
93.
94.
Proteomic characterisation of Echinococcus granulosus hydatid cyst fluid from sheep, cattle and humans 总被引:1,自引:0,他引:1
The hydatid cyst fluid (HCF) of Echinococcus granulosus is a complex biological mixture containing a wide range of proteins of both parasite and host origin. Using a combination of in- and off-gel protein fractionation techniques and tandem mass spectrometry 130 HCF proteins were identified from fertile cysts of sheep and human origin and infertile cysts from cattle. Forty-eight proteins were of parasite origin including Antigen 5 and Antigen B--the most abundant parasite proteins, thioredoxin, low-density lipoprotein receptors, cyclophilin and ferritin. Across the three host species the identified HCF proteins were broadly similar although, based on spectral counts, three proteins, including an antigen B isoform, were more abundant in sheep HCF compared with the fluids of cattle and human origin. Eighty-two host proteins were identified in HCF from the three species. Host plasma proteins were the most abundant, although approximately thirty of the host proteins that were identified are not considered constituents of plasma. The identification of parasite heat shock proteins and annexin A13 exclusively in infertile cysts, along with an increased spectral count for cathepsin B, supports the hypothesis of increased cellular stress and apoptosis as the cause of their infertility. 相似文献
95.
The identification of species constitutes the first basic step in phylogenetic studies, biodiversity monitoring and conservation. DNA barcoding, i.e. the sequencing of a short standardized region of DNA, has been proposed as a new tool for animal species identification. The present study provides an update on the composition of shark in the Egyptian Mediterranean waters off Alexandria, since the latest study to date was performed 30 years ago, DNA barcoding was used in addition to classical taxonomical methodologies. Thus, 51 specimen were DNA barcoded for a 667 bp region of the mitochondrial COI gene. Although DNA barcoding aims at developing species identification systems, some phylogenetic signals were apparent in the data. In the neighbor-joining tree, 8 major clusters were apparent, each of them containing individuals belonging to the same species, and most with 100% bootstrap value. This study is the first to our knowledge to use DNA barcoding of the mitochondrial COI gene in order to confirm the presence of species Squalus acanthias, Oxynotus centrina, Squatina squatina, Scyliorhinus canicula, Scyliorhinus stellaris, Mustelus mustelus, Mustelus punctulatus and Carcharhinus altimus in the Egyptian Mediterranean waters. Finally, our study is the starting point of a new barcoding database concerning shark composition in the Egyptian Mediterranean waters (Barcoding of Egyptian Mediterranean Sharks [BEMS], http://www.boldsystems.org/views/projectlist.php?Barcoding%20Fish%20%28FishBOL%29). 相似文献
96.
The ATR-Chk1 DNA damage checkpoint pathway is a critical regulator of the cellular response to DNA damage and replication stress in human cells. The variety of environmental, chemotherapeutic, and carcinogenic agents that activate this signal transduction pathway do so primarily through the formation of bulky adducts in DNA and subsequent effects on DNA replication fork progression. Because there are many protein-protein and protein-DNA interactions proposed to be involved in activation and/or maintenance of ATR-Chk1 signaling in vivo, we systematically analyzed the association of a number of ATR-Chk1 pathway proteins with relevant checkpoint-inducing DNA structures in vitro. These DNA substrates included single-stranded DNA, branched DNA, and bulky adduct-containing DNA. We found that many checkpoint proteins show a preference for single-stranded, branched, and bulky adduct-containing DNA in comparison to undamaged, double-stranded DNA. We additionally found that the association of checkpoint proteins with bulky DNA damage relative to undamaged DNA was strongly influenced by the ionic strength of the binding reaction. Interestingly, among the checkpoint proteins analyzed the checkpoint mediator proteins Tipin and Claspin showed the greatest differential affinity for checkpoint-inducing DNA structures. We conclude that the association and accumulation of multiple checkpoint proteins with DNA structures indicative of DNA damage and replication stress likely contribute to optimal ATR-Chk1 DNA damage checkpoint responses. 相似文献
97.
Crystel Bonnet M’hamed Grati Sandrine Marlin Jacqueline Levilliers Jean-Pierre Hardelin Marine Parodi Magali Niasme-Grare Diana Zelenika Marc Délépine Delphine Feldmann Laurence Jonard Aziz El-Amraoui Dominique Weil Bruno Delobel Christophe Vincent Hélène Dollfus Marie-Madeleine Eliot Albert David Catherine Calais Jacqueline Vigneron Bettina Montaut-Verient Dominique Bonneau Jacques Dubin Christel Thauvin Alain Duvillard Christine Francannet Thierry Mom Didier Lacombe Françoise Duriez Valérie Drouin-Garraud Marie-Françoise Thuillier-Obstoy Sabine Sigaudy Anne-Marie Frances Patrick Collignon Georges Challe Rémy Couderc Mark Lathrop José-Alain Sahel Jean Weissenbach Christine Petit Françoise Denoyelle 《Orphanet journal of rare diseases》2011,6(1):1-19
Background
Usher syndrome (USH) combines sensorineural deafness with blindness. It is inherited in an autosomal recessive mode. Early diagnosis is critical for adapted educational and patient management choices, and for genetic counseling. To date, nine causative genes have been identified for the three clinical subtypes (USH1, USH2 and USH3). Current diagnostic strategies make use of a genotyping microarray that is based on the previously reported mutations. The purpose of this study was to design a more accurate molecular diagnosis tool.Methods
We sequenced the 366 coding exons and flanking regions of the nine known USH genes, in 54 USH patients (27 USH1, 21 USH2 and 6 USH3).Results
Biallelic mutations were detected in 39 patients (72%) and monoallelic mutations in an additional 10 patients (18.5%). In addition to biallelic mutations in one of the USH genes, presumably pathogenic mutations in another USH gene were detected in seven patients (13%), and another patient carried monoallelic mutations in three different USH genes. Notably, none of the USH3 patients carried detectable mutations in the only known USH3 gene, whereas they all carried mutations in USH2 genes. Most importantly, the currently used microarray would have detected only 30 of the 81 different mutations that we found, of which 39 (48%) were novel.Conclusions
Based on these results, complete exon sequencing of the currently known USH genes stands as a definite improvement for molecular diagnosis of this disease, which is of utmost importance in the perspective of gene therapy. 相似文献98.
Background
Following an AMI, it is important for patients and their physicians to appreciate the subsequent risk of death, and the potential benefits of invasive cardiac procedures and secondary preventive therapy. Studies, to-date, have focused largely on high-risk populations. We wished to determine the risk of death in a population-derived cohort of 2,887 patients after a first acute myocardial infarction (AMI).Methods
Logistic regression and survival analysis were conducted to investigate the effect of different baseline characteristics, pharmacological therapies and revascularization procedures on coronary heart disease (CHD) and all-cause mortality outcomes.Results
Within five years 44.4% of patients died (27.1% short-term [<30 days] and 23.7% longer-term [≥30 days]). Percutaneous transluminal coronary angioplasty (Adjusted Hazards Ratio (AHR) = 0.49, 95% Confidence Interval (CI) 0.26–0.93), β-blockers (AHR = 0.58, 95%CI 0.46–0.74) and statins (AHR = 0.60, 95%CI 0.47–0.77) were all associated with significant reductions in longer-term CHD-related mortality. However, not all patients received secondary preventive therapy (8.7%). Diabetes (AHR = 1.83, 95%CI 1.43–2.34), stroke (AHR = 1.73, 95%CI 1.35–2.22), heart failure (AHR = 1.69, 95%CI 1.28–2.22), smoking (AHR = 1.72, 95%CI 1.18–2.51) and obesity (>30 kg/m2; AHR = 1.39, 95%CI 1.01–1.90) increased the risk of longer-term mortality independent of other risk factors.Conclusions
It is encouraging that the coronary procedure PTCA and pharmacological secondary prevention therapies were found to be strongly associated with an important reduced risk of subsequent death, although not all patients received these interventions. Smoking, being obese and having cardiovascular related disease at baseline were also associated with an increased likelihood of longer-term mortality, independent of other baseline characteristics. Thus, the provision of smoking cessation, advice on diet (for obese patients) and optimal treatment is likely to be crucial for reducing mortality in all patients after AMI. 相似文献99.
Cerebral glucose metabolism and cerebral blood flow are altered in patients with lupus who have neuropsychiatric manifestations. However, the dynamics of changes in glucose metabolism remain unclear. The present study was undertaken using 1H and 13C nuclear magnetic resonance (NMR) spectroscopy to determine the rates of incorporation of glucose into amino acids and lactate via cell-specific pathways in mice with lupus. In the well-established MRL/lpr lupus mouse model, 24-week-old mice had a significant increase of 30-80% (P<0.001) in total brain glutamine, glutamate and lactate concentrations, while alanine, aspartate, N-acetyl aspartate (NAA) and gamma-aminobutyric acid (GABA) remained unchanged as compared to the congenic MRL+/+control mice. Although succinate concentration was increased in lupus brain, it did not reach statistical significance. Furthermore, 13C isotopomer analysis showed a selective increase of de novo synthesis of lactate from [1-(13)C] glucose through glycolysis resulting in 1.5-fold increased fractional 13C enrichments in lactate in MRL/lpr mice. [4-(13)C] Glutamate, which is synthesized mainly by the neuronal pyruvate dehydogenase, was selectively increased, while [2-(13)C] and [3-(13)C] GABA synthesis were decreased by 25% compared to controls. In accordance with the total concentrations, aspartate synthesis remained unaltered in brains of lupus mice, while alanine synthesis was elevated, indicating increased utilization of alanine. Creatine was unchanged in MRL/lpr mice as compared to controls. An interesting finding was a significant increase (158%, P<0.005) in choline concentration in MRL/lpr mice while the myo-inositol concentration remained the same in both groups. Furthermore a significant increase in total brain water content was observed, indicative of possible edema. In conclusion, the cumulative effect of increased brain lactate synthesis, altered glucose metabolism and intracellular glutamine accumulation could be an important mechanism causing brain pathology in SLE. The alteration in metabolites could alter downstream pathways and cause neurological dysfunction. Future NMR spectroscopic studies using stable isotopes and real-time measurements of metabolic rates, along with levels of metabolites in plasma and cerebrospinal fluid, could be valuable in the elucidation of the cerebral metabolic consequences of systemic lupus erythematosis (SLE) in humans. 相似文献
100.
Qabar A Nelson M Guzman J Corun C Hwang BJ Steinberg M 《Journal of biochemical and molecular toxicology》2005,19(4):213-225
We compared the effects of overexpressing a tightly regulated anti-inflammatory cytokine, interleukin 10 (IL-10), and the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) on sulfur mustard induced cytotoxicity in human epidermal keratinocytes. Both cytokines were overexpressed when compared with the cells transfected with the empty vector as determined by quantitative ELISA. Cells overexpressing interleukin 10 suppressed the pro-inflammatory cytokines interleukin 8 and interleukin 6 following exposure to 50-300 microM sulfur mustard. These cells exhibited delayed onset of sulfur mustard induced cell death. On the other hand, cells overexpressing tumor necrosis factor alpha induced a sustained elevation in both interleukin 6 and 8 expression following exposure to 50-300 microM sulfur mustard. These cells were sensitized to the effects of sulfur mustard that resulted in an increased sulfur mustard induced cell death. Normal human epidermal keratinocytes treated with sulfur mustard exhibited elevated levels of tumor necrosis factor alpha expression and increased activity of nuclear factor kappa B. Gene array data indicated that cells overexpressing interleukin 10 induced several genes that are involved in growth promotion and cell-fate determination. We, therefore, identify IL-10 and TNF-alpha signal transduction pathways and their components as possible candidates for early therapeutic intervention against sulfur mustard induced cell injury. 相似文献