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Safak Kalindamar Adef O. Kordon Hossam Abdelhamed Wei Tan Lesya M. Pinchuk Attila Karsi 《Cellular microbiology》2020,22(3)
Edwardsiella ictaluri is a Gram‐negative facultative anaerobe that can survive inside channel catfish phagocytes. E. ictaluri can orchestrate Type VI Secretion System (T6SS) for survival in catfish macrophages. evpP encodes one of the T6SS translocated effector proteins. However, the role of evpP in E. ictaluri is still unexplored. In this work, we constructed an E. ictaluri evpP mutant (EiΔevpP) and assessed its survival under complement and oxidative stress. Persistence of EiΔevpP in catfish as well as attachment and invasion in catfish macrophage and ovary cells were determined. Further, virulence of EiΔevpP in catfish and apoptosis it caused in macrophages were explored. EiΔevpP behaved same as wild type (EiWT) under complement and oxidative stress in complex media, whereas oxidative stress affected mutant's survival significantly in minimal media (p < .05). Persistence of EiΔevpP in live catfish and uptake and survival inside peritoneal macrophages were similar. The attachment and invasion capabilities of EiΔevpP in catfish ovary cells were significantly less than that of EiWT (p < .05). Although EiΔevpP showed reduced attenuation in catfish, causing decreased catfish mortality compared with EiWT (44.73% vs. 67.53%), this difference was not significant. The apoptosis assay using anterior kidney macrophages indicated that the number of live macrophages exposed to EiΔevpP was significantly higher compared with EiWT exposed macrophages at 24‐hr post‐treatment (p < .05). However, there were no significant differences in the early and late apoptosis. Remarkably, necrosis in EiΔevpP exposed macrophages was significantly less than that of EiWT exposed macrophages at 24 hr (p < .05). Our results demonstrated that evpP is required for colonisation of catfish ovary cells and increased apoptosis and necrosis in anterior kidney macrophages. 相似文献
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Citric acid production by Aspergillus niger grown on orange peel medium fortified with cane molasses
Hossam S. Hamdy 《Annals of microbiology》2013,63(1):267-278
Citric acid production (CAP) by Aspergillus niger was obtained following culture on an orange peel medium (OPM) fortified with cane molasses. The key physico-chemical parameters influencing CAP, such as bed loading, moisture levels, volume and age of inoculum, initial pH, incubation temperature and duration, agitation rate, sugar concentration, addition of nitrogen and phosphorus sources, treatment of molasses and the addition of different low levels of alcohols, were assessed. The suitability of molasses to increase the concentration of sugar in the fermentation medium without previous treatments with EDTA or ferro-cyanide was indicated. Maximum amounts of CA (640 g/kg orange peel) were obtained after 72 h of incubation on an OPM moisturized to 65 %?w/v, with bed loading of 20 %, an initial pH of 5, a temperature of 30 °C, an agitation rate of 250 rpm, with fortification of the medium with molasses at a final sugar concentration of 14 % in the presence of 3.5 % methanol. 相似文献
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Hossam El-Sheikh Ali Go Kitahara Kazumi Nibe Ryoji Yamaguchi Yoichiro Horii Samy Zaabel Takeshi Osawa 《Theriogenology》2013
Granulosa-theca cell tumors (GTCTs) are the most frequently reported ovarian tumors in cattle. Clinically, GTCTs could be confused with other ovarian abnormalities; therefore, the only definitive diagnosis for such tumors is histopathology of a biopsy from the affected ovary. However, this is an invasive technique and unsuitable for farm conditions. As a result, the key aim of this study was to evaluate the diagnostic value of anti-Müllerian hormone (AMH), a glycoprotein hormone that is synthesized exclusively by ovarian granulosa cells, as a sensitive noninvasive biomarker for diagnosing GTCTs in cattle. To achieve this aim, we conducted two experiments. In experiment 1, four clinically healthy Japanese Black cows had blood samples taken daily over one estrous cycle to characterize their AMH profiles throughout the estrous cycle. Additionally, single blood samples were collected from 21 cyclic cows to clarify the physiological range of AMH. In experiment 2, cows with histologically confirmed GTCT (GTCT group, n = 9) and cows affected with cystic ovarian disease (COD group, n = 8) had one blood sample taken before extraction of the tumorous ovary or therapeutic treatment for the COD. Blood samples (n = 105) from cyclic cows (n = 25) in experiment 1 were assigned as a physiologically cyclic group (PC group). Plasma AMH, immunoreactive inhibin (ir-INH), estradiol-17β (E2), testosterone (T), and progesterone (P4) concentrations were assayed in all samples. In experiment 1, the mean plasma AMH concentration was 0.09 ± 0.003 ng/mL and did not show substantial fluctuation throughout the estrous cycle. In experiment 2, plasma AMH, ir-INH, and E2 concentrations were significantly elevated in the GTCT group in comparison with the PC group; among these parameters, only the AMH concentrations were significantly higher in the GTCT group than in the COD group. The area under the receiver operating characteristic curve of AMH for diagnosis of GTCT was 0.99 and was significantly higher than that of ir-INH (P < 0.001) and E2 (P < 0.01). Moreover, the AMH at a cutoff point of ≥0.36 ng/mL had the highest diagnostic accuracy (99.2%), sensitivity (100%), and specificity (99.1%) compared with the other tested parameters. In conclusion, plasma AMH concentration is probably a more reliable and sensitive biomarker for bovine GTCTs than the concentrations of ir-INH or ovarian steroids. 相似文献
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Ibrahim Sabrin R. M. Abdallah Hossam M. El-Halawany Ali M. Mohamed Gamal A. 《Phytochemistry Reviews》2016,15(2):197-220
Phytochemistry Reviews - Thiophenes are a class of heterocyclic aromatic compounds based on a five-membered ring made up of one sulfur and four carbon atoms. The thiophene nucleus is well... 相似文献
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Background
Selecting a subset of relevant properties from a large set of features that describe a dataset is a challenging machine learning task. In biology, for instance, the advances in the available technologies enable the generation of a very large number of biomarkers that describe the data. Choosing the more informative markers along with performing a high-accuracy classification over the data can be a daunting task, particularly if the data are high dimensional. An often adopted approach is to formulate the feature selection problem as a biobjective optimization problem, with the aim of maximizing the performance of the data analysis model (the quality of the data training fitting) while minimizing the number of features used.Results
We propose an optimization approach for the feature selection problem that considers a “chaotic” version of the antlion optimizer method, a nature-inspired algorithm that mimics the hunting mechanism of antlions in nature. The balance between exploration of the search space and exploitation of the best solutions is a challenge in multi-objective optimization. The exploration/exploitation rate is controlled by the parameter I that limits the random walk range of the ants/prey. This variable is increased iteratively in a quasi-linear manner to decrease the exploration rate as the optimization progresses. The quasi-linear decrease in the variable I may lead to immature convergence in some cases and trapping in local minima in other cases. The chaotic system proposed here attempts to improve the tradeoff between exploration and exploitation. The methodology is evaluated using different chaotic maps on a number of feature selection datasets. To ensure generality, we used ten biological datasets, but we also used other types of data from various sources. The results are compared with the particle swarm optimizer and with genetic algorithm variants for feature selection using a set of quality metrics. 相似文献10.
Al‐Sayed Al‐Soudy Tsuyoshi Nakanishi Seiya Mizuno Yoshikazu Hasegawa Hossam H. Shawki Megumi C. Katoh Walaa A. Basha Abdelaziz E. Ibrahim Hany A. El‐Shemy Hiroyoshi Iseki Atsushi Yoshiki Youhei Hiromori Hisamitsu Nagase Satoru Takahashi Hisashi Oishi Fumihiro Sugiyama 《Genesis (New York, N.Y. : 2000)》2016,54(7):389-397
Spermatogenesis is a complex and highly regulated process by which spermatogonial stem cells differentiate into spermatozoa. To better understand the molecular mechanisms of the process, the Cre/loxP system has been widely utilized for conditional gene knockout in mice. In this study, we generated a transgenic mouse line that expresses Cre recombinase under the control of the 2.5 kbp of the Prolactin family 3, subfamily b, member 1 (Prl3b1) gene promoter (Prl3b1‐cre). Prl3b1 was initially reported to code for placental lactogen 2 (PL‐2) protein in placenta along with increased expression toward the end of pregnancy. PL‐2 was found to be expressed in germ cells in the testis, especially in spermatocytes. To analyze the specificity and efficiency of Cre recombinase activity in Prl3b1‐cre mice, the mice were mated with reporter R26GRR mice, which express GFP ubiquitously before and tdsRed exclusively after Cre recombination. The systemic examination of Prl3b1‐cre;R26GRR mice revealed that tdsRed‐positive cells were detected only in the testis and epididymis. Fluorescence imaging of Prl3b1‐cre;R26GRR testes suggested that Cre‐mediated recombination took place in the germ cells with approximately 74% efficiency determined by in vitro fertilization. In conclusion, our results suggest that the Prl3b1‐cre mice line provides a unique resource to understand testicular germ‐cell development. genesis 54:389–397, 2016. © 2016 Wiley Periodicals, Inc. 相似文献