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排序方式: 共有250条查询结果,搜索用时 17 毫秒
31.
Nicola G. Ghazi Emad B. Abboud Sawsan R. Nowilaty Hisham Alkuraya Abdulrahman Alhommadi Huimin Cai Rui Hou Wen-Tao Deng Sanford L. Boye Abdulrahman Almaghamsi Fahad Al Saikhan Hassan Al-Dhibi David Birch Christopher Chung Dilek Colak Matthew M. LaVail Douglas Vollrath Kirsten Erger Wenqiu Wang Thomas Conlon Kang Zhang William Hauswirth Fowzan S. Alkuraya 《Human genetics》2016,135(3):327-343
32.
Atheer M. Mohammed Ibrahim A. Khardali Magbool E. Oraiby Abdulrahman F. Hakami Emad S. Shaheen Ibrahim M. Ageel Eyas H. Abutawil Gasem M. Abu-Taweel 《Saudi Journal of Biological Sciences》2021,28(11):6097-6111
Cannabis is an annual herbaceous plant sometimes grown for decoration and used as bird food that looks like flax. The study wanted to determine if a Cannabis extract may have an effect on how anxious and depressed the female mice behaved. forty healthy female mice were divided into four groups. Tap water was administered to the first group (control). Ethanol was administered to second group (positive control). The third and four groups were given 1 and 2 mg/kg cannabis extract respectively. Treatment continued for 14 days. After therapy, the light–dark chamber, forced swimming, tail suspension, plus lamb and open field tests were done to assess anxiety and depressive behavior. The results indicated that the anxiety and depression were increased in treated females significantly compared to control. Biochemical results showed that DA,5-HT, AChE, GSH, GST, CAT and SOD were decreased while TBARS, corticosterone and cortisol were increased. In conclusion, cannabis effects this kind of females’ behavior but the mechanisms are not clear yet. We need more researches on this trend. 相似文献
33.
Plankton abundance in relation to physicochemical factors in the Bui reservoir of Ghana's Black Volta River
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The relationship between physicochemical factors and plankton abundance in the newly created Bui reservoir was studied during 2011 and 2012. The objective was to assess the influence of physicochemical factors on plankton abundance and provide data for monitoring the hydrobiology of the newly created Bui reservoir. Two sampling stations were selected on the Black Volta upstream (Bui) and downstream (Bamboi) of the dam, with samples taken pre‐ and postimpoundment during the study period. Canonical Correspondence Analysis (CCA) was used to trace temporal plankton community changes and to examine the relationships between species composition and physicochemical variables. The relative abundance of some phytoplankton species such as Anabaena sp., Planktothrix sp. and Scenedesmus sp. was directly correlated to nitrates. CCA indicated that physicochemical variables explained 41–64% of zooplankton and 8–12% of phytoplankton variation. Hence, there were correlations between environmental variables and the structure of plankton assemblages. This feature should therefore be used for bio‐monitoring of environmental variables of the river by the Bui Power Authority to ensure protection of the aquatic biota downstream of the Bui dam. 相似文献
34.
Histone H4K20 tri‐methylation at late‐firing origins ensures timely heterochromatin replication
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![点击此处可从《The EMBO journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Charlotte Grimaud Paulina Prorok Christelle Cayrou Gunnar Schotta Alhassan F Abdelsamie Jérôme Déjardin Marcel Méchali Giuseppe Baldacci Claude Sardet Jean‐Charles Cadoret Aloys Schepers Eric Julien 《The EMBO journal》2017,36(18):2726-2741
Among other targets, the protein lysine methyltransferase PR‐Set7 induces histone H4 lysine 20 monomethylation (H4K20me1), which is the substrate for further methylation by the Suv4‐20h methyltransferase. Although these enzymes have been implicated in control of replication origins, the specific contribution of H4K20 methylation to DNA replication remains unclear. Here, we show that H4K20 mutation in mammalian cells, unlike in Drosophila, partially impairs S‐phase progression and protects from DNA re‐replication induced by stabilization of PR‐Set7. Using Epstein–Barr virus‐derived episomes, we further demonstrate that conversion of H4K20me1 to higher H4K20me2/3 states by Suv4‐20h is not sufficient to define an efficient origin per se, but rather serves as an enhancer for MCM2‐7 helicase loading and replication activation at defined origins. Consistent with this, we find that Suv4‐20h‐mediated H4K20 tri‐methylation (H4K20me3) is required to sustain the licensing and activity of a subset of ORCA/LRWD1‐associated origins, which ensure proper replication timing of late‐replicating heterochromatin domains. Altogether, these results reveal Suv4‐20h‐mediated H4K20 tri‐methylation as a critical determinant in the selection of active replication initiation sites in heterochromatin regions of mammalian genomes. 相似文献
35.
Fahd Al-Mulla Mahera Abdulrahman Govindarajulu Varadharaj Nadeem Akhter Jehoram T Anim 《The journal of histochemistry and cytochemistry》2005,53(5):621-629
Breast cancer is a major cause of cancer-related mortality in women. There are major discrepancies concerning the usefulness of various antibodies in detecting breast cancer susceptibility gene 1 (BRCA1) protein and its subcellular localization. The aim of the present study was to determine the specificity and sensitivity of immunohistochemistry (IHC) as a screening method for demonstrating BRCA1 expression. BRCA1 gene expression in archival paraffin-embedded breast cancer tissues was studied simultaneously at the protein and mRNA levels, and the two findings were compared. Forty-eight archival paraffin-embedded breast cancer tissues were studied for BRCA1 gene expression at protein level by IHC using four different antibodies against different BRCA1 epitopes and at mRNA level using real-time RT-PCR. BRCA1 mRNA expression was reduced or absent in 79% of the samples, and this finding correlated significantly with loss of BRCA1 protein expression in 83% of breast cancer tissues using one BRCA1 antibody studied (AB-1, against N-terminus epitope). The specificity of this antibody was 91.3%, and its sensitivity was 66.6%. There was no significant correlation between BRCA1 mRNA and protein expression as demonstrated by the remaining three antibodies. Antibody 8F7 had the highest sensitivity of 100%, but its specificity was 30.4% if mRNA levels were considered as the reference standard. 相似文献
36.
Mohammed M. Alanazi Elwan Alaa Nawaf A. Alsaif Ahmad J. Obaidullah Hamad M. Alkahtani Abdulrahman A. Al-Mehizia Sultan M. Alsubaie Mohammed S. Taghour Ibrahim H. Eissa 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):1732
There is an urgent need to design new anticancer agents that can prevent cancer cell proliferation even with minimal side effects. Accordingly, two new series of 3-methylquinoxalin-2(1H)-one and 3-methylquinoxaline-2-thiol derivatives were designed to act as VEGFR-2 inhibitors. The designed derivatives were synthesised and evaluated in vitro as cytotoxic agents against two human cancer cell lines namely, HepG-2 and MCF-7. Also, the synthesised derivatives were assessed for their VEGFR-2inhibitory effect. The most promising member 11e were further investigated to reach a valuable insight about its apoptotic effect through cell cycle and apoptosis analyses. Moreover, deep investigations were carried out for compound 11e using western-plot analyses to detect its effect against some apoptotic and apoptotic parameters including caspase-9, caspase-3, BAX, and Bcl-2. Many in silico investigations including docking, ADMET, toxicity studies were performed to predict binding affinity, pharmacokinetic, drug likeness, and toxicity of the synthesised compounds. The results revealed that compounds 11e, 11g, 12e, 12g, and 12k exhibited promising cytotoxic activities (IC50 range is 2.1 − 9.8 µM), comparing to sorafenib (IC50 = 3.4 and 2.2 µM against MCF-7 and HepG2, respectively). Moreover, 11b, 11f, 11g, 12e, 12f, 12g, and 12k showed the highest VEGFR-2 inhibitory activities (IC50 range is 2.9 − 5.4 µM), comparing to sorafenib (IC50 = 3.07 nM). Additionally, compound 11e had good potential to arrest the HepG2 cell growth at G2/M phase and to induce apoptosis by 49.14% compared to the control cells (9.71%). As well, such compound showed a significant increase in the level of caspase-3 (2.34-fold), caspase-9 (2.34-fold), and BAX (3.14-fold), and a significant decrease in Bcl-2 level (3.13-fold). For in silico studies, the synthesised compounds showed binding mode similar to that of the reference compound (sorafenib). 相似文献
37.
Abdulrahman GO 《The Yale journal of biology and medicine》2011,84(3):311-319
Trinucleotide repeat disorders are a set of genetic disorders characterized by the expansion of certain genes of a segment of DNA that contains a repeat of three nucleotides, thus exceeding the normal stable threshold. These repeats in the DNA cause repeats of a specific amino acid in the protein sequence, and it is the repeated amino acid that results in a defective protein. Huntington's disease is a well-known genetic disorder associated with trinucleotide repeat expansions. Patients first present clinically in midlife and manifest a typical phenotype of sporadic, rapid, and involuntary control of limb movement; stiffness of limbs; impaired cognition; severe psychiatric disturbances; and ultimately, death. There have been a number of therapeutic advances in the treatment of Huntington's disease, such as foetal neural transplantation, RNA interference, and transglutaminase inhibitor. Although there is intensive research into Huntington's disease and recent findings seem promising, effective therapeutic strategies may not be developed until the next few decades. 相似文献
38.
39.
A Simple Isothermal DNA Amplification Method to Screen Black Flies for Onchocerca volvulus Infection
Andy Alhassan Benjamin L. Makepeace Elwyn James LaCourse Mike Y. Osei-Atweneboana Clotilde K. S. Carlow 《PloS one》2014,9(10)
Onchocerciasis is a debilitating neglected tropical disease caused by infection with the filarial parasite Onchocerca volvulus. Adult worms live in subcutaneous tissues and produce large numbers of microfilariae that migrate to the skin and eyes. The disease is spread by black flies of the genus Simulium following ingestion of microfilariae that develop into infective stage larvae in the insect. Currently, transmission is monitored by capture and dissection of black flies and microscopic examination of parasites, or using the polymerase chain reaction to determine the presence of parasite DNA in pools of black flies. In this study we identified a new DNA biomarker, encoding O. volvulus glutathione S-transferase 1a (OvGST1a), to detect O. volvulus infection in vector black flies. We developed an OvGST1a-based loop-mediated isothermal amplification (LAMP) assay where amplification of specific target DNA is detectable using turbidity or by a hydroxy naphthol blue color change. The results indicated that the assay is sensitive and rapid, capable of detecting DNA equivalent to less than one microfilaria within 60 minutes. The test is highly specific for the human parasite, as no cross-reaction was detected using DNA from the closely related and sympatric cattle parasite Onchocerca ochengi. The test has the potential to be developed further as a field tool for use in the surveillance of transmission before and after implementation of mass drug administration programs for onchocerciasis. 相似文献
40.
Sandra Jose Sreevidya
S. Devi Anjana Sajeev Sosmitha Girisa Mohammed
S. Alqahtani Mohamed Abbas Abdulrahman Alshammari Gautam Sethi Ajaikumar
B. Kunnumakkara 《Bioscience reports》2023,43(3)
Farnesoid X receptor (FXR) modulates the expression of genes involved in lipid and carbohydrate homeostasis and inflammatory processes. This nuclear receptor is likely a tumor suppressor in several cancers, but its molecular mechanism of suppression is still under study. Several studies reported that FXR agonism increases the survival of colorectal, biliary tract, and liver cancer patients. In addition, FXR expression was shown to be down-regulated in many diseases such as obesity, irritable bowel syndrome, glomerular inflammation, diabetes, proteinuria, and ulcerative colitis. Therefore, development of novel FXR agonists may have significant potential in the prevention and treatment of these diseases. In this scenario, computer-aided drug design procedures can be resourcefully applied for the rapid identification of promising drug candidates. In the present study, we applied the molecular docking method in conjunction with molecular dynamics (MD) simulations to find out potential agonists for FXR based on structural similarity with the drug that is currently used as FXR agonist, obeticholic acid. Our results showed that alvimopan and montelukast could be used as potent FXR activators and outperform the binding affinity of obeticholic acid by forming stable conformation with the protein in silico. However, further investigational studies and validations of the selected drugs are essential to figure out their suitability for preclinical and clinical trials. 相似文献