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151.
Sex hormones such as estrogen and testosterone are essential for sexually dimorphic behaviors in vertebrates. However, the hormone-activated molecular mechanisms that control the development and function of the underlying neural circuits remain poorly defined. We have identified numerous sexually dimorphic gene expression patterns in the adult mouse hypothalamus and amygdala. We find that adult sex hormones regulate these expression patterns in a sex-specific, regionally restricted manner, suggesting that these genes regulate sex typical behaviors. Indeed, we find that mice with targeted disruptions of each of four of these genes (Brs3, Cckar, Irs4, Sytl4) exhibit extremely specific deficits in sex specific behaviors, with single genes controlling the pattern or extent of male sexual behavior, male aggression, maternal behavior, or female sexual behavior. Taken together, our findings demonstrate that various components of sexually dimorphic behaviors are governed by separable genetic programs. 相似文献
152.
Osama M. E. Seidahmed Safa A. Hassan Mohamed A. Soghaier Hanna A. M. Siam Fayez T. A. Ahmed Mubarak M. Elkarsany Suad M. Sulaiman 《PLoS neglected tropical diseases》2012,6(9)
Background
Dengue is an emerging health problem in several coastlines along the Red Sea. The objective of the present work is to elucidate spatial and temporal patterns of dengue transmission in Port Sudan.Methods/Findings
A longitudinal study with three cross-sectional surveys was carried out in upper, middle and lower class neighborhoods, from November 2008 to October 2009. Monthly, entomological surveys were followed by serological surveys in dengue vector-positive houses. Meteorological records were obtained from two weather stations in the city during the same time. Overall, 2825 houses were inspected. Aedes aegypti represented 65% (35,714/54,944) and 68% (2526/3715) of the collected larvae and pupae, respectively. Out of 4640 drinking water containers, 2297 were positive for Ae. aegypti. Clay-pots “Zeirr” followed by plastic barrels were key productive containers for pupae of dengue vector, 63% (n = 3959) and 26% (n = 1651), respectively. A total of 791 blood samples were tested using PanBio Capture/Indirect IgM ELISA. Overall, the sero-prevalence rate of dengue ranged between 3%–8% (41/791), compared to an incidence of 29–40 new cases per 10,000 (193/54886) in the same examined population. Lower and middle class neighborhoods had higher entomological indices compared with upper class ones (p<0.001). Although, dengue incidence rate was significantly lower in the middle and lower class neighborhoods (F = 73.97, d.f. = 2, p<0.001), no difference in IgM prevalence was shown. The city is subject to two transmission peaks in the winter (i.e. November–January), and summer (i.e. June–August). The serological peaks of dengue are preceded by entomological peaks that occur before the onset of winter (November) and summer (March) respectively.Conclusion
Dengue incidence is heterogeneously distributed across the neighborhoods of Port Sudan and exhibits a bi-cyclic intra-annual pattern. Hence, it should be feasible to carry out timely vector control measures to prevent or reduce dengue transmission. 相似文献153.
Mostafa A. El-Sayed Ali A. Shabaka Osama A. El-Shabrawy Nemat A. Yassin Sawsan S. Mahmoud Siham M. El-Shenawy Emad Al-Ashqar Wael H. Eisa Niveen M. Farag Marwa A. El-Shaer Nabila Salah Ahmed M. Al-Abd 《PloS one》2013,8(10)
Gold nanorods (GNR) within tumor microregions are characterized by their ability to absorb near IR light and emit heat in what is called photoplasmonic effect. Yet, the efficacy of nanoparticles is limited due to intratumoral tissue distribution reasons. In addition, distribution of GNRs to normal tissue might result in non specific toxicity. In the current study, we are assessing the intratumoral and tissue distribution of PEGylated GNRs on the top of its antitumor characteristics when given intravenously or intratumoral to solid tumor bearing mice and coupled with laser photoplasmonic sessions. PEGylated GNRs with a longitudinal size of less than 100 nm were prepared with aspect ratio of 4.6 showing strong surface plasmon absorption at wavelength 800 nm. Pharmacokinetics of GNR after single I.V. administration (0.1 mg/kg) showed very short systemic circulating time (less than 3 h). On the other hand, tissue distribution of I.V. GNR (0.1 mg/kg) to normal animals showed preferential deposition in spleen tissue. Repeated administration of I.V. GNR resulted in preferential accumulation in both liver and spleen tissues. In addition, I.V. administration of GNR to Ehrlich carcinoma tumor bearing mice resulted in similar tissue distribution; tumor accumulation and anti-tumor effect compared to intratumoral administration. In conclusion, the concentration of GNR achieved within tumors microregions after I.V. administration was comparable to I.T. administration and sufficient to elicit tumoral growth arrest when coupled with laser-aided photoplasmonic treatment. 相似文献
154.
Mohd Rehan Ejaz Ahmad Ishfaq A. Sheikh Adel M. Abuzenadah Ghazi A. Damanhouri Osama S. Bajouh Samera F. AlBasri Mansour M. Assiri Mohd A. Beg 《PloS one》2015,10(9)
Exposure to toxic industrial chemicals that have capacity to disrupt the endocrine system, also known as endocrine disrupting chemicals (EDCs), has been increasingly associated with reproductive problems in human population. Bisphenol A (BPA; 4,4''-(propane-2,2-diyl)diphenol) and 4-tert-octylphenol (OP; 4-(1,1,3,3-tetramethylbutyl)phenol) are among the most common environmental contaminants possessing endocrine disruption properties and are present in plastics, epoxy resins, detergents and other commercial products of common personal and industrial use. A metabolite of BPA, 4-Methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene (MBP) is about 1000 times more biologically active compared to BPA. Epidemiological, clinical, and experimental studies have shown association of BPA and OP with adverse effects on male and female reproductive system in human and animals. The endocrine disruption activity can occur through multiple pathways including binding to steroid receptors. Androgen receptor (AR) and progesterone receptor (PR) are critical for reproductive tract growth and function. Structural binding characterization of BPA, MBP, and OP with AR and PR using molecular docking simulation approaches revealed novel interactions of BPA with PR, and MBP and OP with AR and PR. For BPA, MBP, and OP, five AR interacting residues Leu-701, Leu-704, Asn-705, Met-742, and Phe-764 overlapped with those of native AR ligand testosterone, and four PR interacting residues Leu-715, Leu-718, Met-756, and Met-759 overlapped with those of PR co-complex ligand, norethindrone. For both the receptors the binding strength of MBP was maximum among the three compounds. Thus, these compounds have the potential to block or interfere in the binding of the endogenous native AR and PR ligands and, hence, resulting in dysfunction. The knowledge of the key interactions and the important amino-acid residues also allows better prediction of potential of xenobiotic molecules for disrupting AR- and PR-mediated pathways, thus, helping in design of less potent alternatives for commercial use. 相似文献
155.
Chahrour O Abdalla A Lam F Midgley C Wang S 《Bioorganic & medicinal chemistry letters》2011,21(10):3066-3069
We herein report the synthesis, biological activity and structure activity relationship of derivatives of benzylstyrylsulfone, benzylstyrylsulfine and benzylsulfonyl-N-phenylacetamide. A lead compound 7 represents a new class of mitotic inhibitors that demonstrates potent anti-proliferative activity and selectively induces cancer cell apoptosis while sparing non-transformed lung fibroblast. 相似文献
156.
Ola M. Gomaa Osama A. Momtaz Hussein Abd El Kareem Riham Fathy 《World journal of microbiology & biotechnology》2011,27(7):1641-1648
Twenty-two local brown rot fungal isolates were obtained from 5 different environmental sources. Fourteen isolates were presumptively
identified as Aspergillus sp. and eight as Penicillium sp. using mycelium and spore morphology. All the fungal isolates were screened for their ability to decolorize Isolan Red and
colored waste water and to produce oxidase activity. Aspergillus isolate 2 was chosen for further study because it could decolorize both dyes and produce oxidase. A 400 bp fragment of the
18S rRNA gene from isolate 2 was analyzed by nucleotide sequence analysis. Blastn analysis of sequence data demonstrated 100%
identity to Aspergillus sp. and isolate 2 was assigned the strain designation Aspergillus sp. EL-2 (Accession number: HM140797). EL-2 could remove up to 80% of Disperse Blue in waste water effluent within 48 h in submerged
shake culture. The decolorization process was energy dependent, growth related, and required viable biomass. EL-2 was able
to grow and decolorize waste water over a broad pH range. Addition of inducers and inhibitors of specific enzymes or families
of enzymes demonstrated the involvement of phenol oxidase (laccase), cytochrome p-450 oxygenase and hydroxyl radicals in the
decolorization process. The data also suggest that it may be practical to enhance decolorizing activity of Aspergillus sp. EL-2 through the metabolic control of fungal degradative pathways by altering media composition. 相似文献
157.
158.
159.
Sara A. Abuelmaali Arwa H. Elaagip Mohammed A. Basheer Ehab A. Frah Fayez T. A. Ahmed Hassabelrasoul F. A. Elhaj Osama M. E. Seidahmed David Weetman Muzamil Mahdi Abdel Hamid 《PloS one》2013,8(11)
Background
Agricultural pesticides may play a profound role in selection of resistance in field populations of mosquito vectors. The objective of this study is to investigate possible links between agricultural pesticide use and development of resistance to insecticides by the major malaria vector Anopheles arabiensis in northern Sudan.Methodology/Principal Findings
Entomological surveys were conducted during two agricultural seasons in six urban and peri-urban sites in Khartoum state. Agro-sociological data were collected from 240 farmers subjected to semi-structured questionnaires based on knowledge attitude and practice (KAP) surveys. Susceptibility status of An. arabiensis (n=6000) was assessed in all sites and during each season using WHO bioassay tests to DDT, deltamethrin, permethrin, Malathion and bendiocarb. KAP analysis revealed that pesticide application was common practice among both urban and peri-urban farmers, with organophosphates and carbamates most commonly used. Selection for resistance is likely to be greater in peri-urban sites where farmers apply pesticide more frequently and are less likely to dispose of surpluses correctly. Though variable among insecticides and seasons, broad-spectrum mortality was slightly, but significantly higher in urban than peri-urban sites and most marked for bendiocarb, to which susceptibility was lowest. Anopheles arabiensis from all sites showed evidence of resistance or suspected resistance, especially pyrethroids. However, low-moderate frequencies of the L1014F kdr allele in all sites, which was very strongly associated with DDT, permethrin and deltamethrin survivorship (OR=6.14-14.67) suggests that resistance could increase rapidly.Conclusions
Ubiquitous multiple-resistance coupled with presence of a clear mechanism for DDT and pyrethroids (kdr L1014F) in populations of An. arabiensis from Khartoum-Sudan suggests careful insecticide management is essential to prolong efficacy. Our findings are consistent with agricultural insecticide use as a source of selection for resistance and argue for coordination between the integrated vector control program and the Ministry of Agriculture to permit successful implementation of rational resistance management strategies. 相似文献160.
J. Max Goodson Mary Tavares Xiaoshan Wang Richard Niederman Maryann Cugini Hatice Hasturk Roula Barake Osama Alsmadi Sabiha Al-Mutawa Jitendra Ariga Pramod Soparkar Jawad Behbehani Kazem Behbehani 《PloS one》2013,8(10)