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61.
Catarina Rato Mehmet Zülfü Yıldız Naşit İğci Kurtuluş Olgun Çetin Ilgaz Aziz Avcı 《Zoology in the Middle East.》2013,59(4):324-331
The Persian Lizard, Iranolacerta brandtii, was until recently considered to be restricted to north-western Iran (Azerbaijan and Esfahan provinces). However, two recent studies have revealed the existence of populations in Eastern Anatolia, extending the range of this species for about 230?km westwards. The fragmented distribution of this species has been considered to be a consequence of the climatic oscillations during the Pleistocene and Holocene, which created events of alternating contact and isolation of populations in distinct glacial refugia. According to our obtained genealogy derived from three mitochondrial fragments (12S rRNA, 16S rRNA and cytb), the Turkish specimens cluster together but form an independent clade, sister to the individuals from Tabriz in Iran. The separation of these two clades is concurrent with the cladogenesis between the Esfahan and Ardabil clades, estimated to have taken place during the late Holocene. 相似文献
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63.
Exosomal GAPDH from Proximal Tubule Cells Regulate ENaC Activity 总被引:1,自引:0,他引:1
Kishore Kumar Jella Ling Yu Qiang Yue Daniel Friedman Billie J. Duke Abdel A. Alli 《PloS one》2016,11(11)
Exosomes are nanometer-scale, cell-derived vesicles that contain various molecules including nucleic acids, proteins, and lipids. These vesicles can release their cargo into adjacent or distant cells and mediate intercellular communication and cellular function. Here we examined the regulation of epithelial sodium channels in mpkCCD cells and distal tubule Xenopus 2F3 cells by exosomes isolated from proximal tubule LLC-PK1 cells. Cultured mpkCCD cells were stained with CTX coupled to a green fluorophore in order to label the cell membranes and freshly isolated exosomes from LLC-PK1 cells were labeled with the red lipophilic dye PKH26 in order to visualize uptake of exosomes into the cells. Single-channel patch clamp recordings showed the open probability of ENaC in Xenopus 2F3 cells and in freshly isolated split-open tubules decreased in response to exogenous application of exosomes derived from LLC-PK1 proximal tubule cells. Active GAPDH was identified within exosomes derived from proximal tubule LLC-PK1 cells. The effect on ENaC activity in Xenopus 2F3 cells was blunted after application of exosomes transfected with the GAPDH inhibitor heptelidic acid. Also, we show GAPDH and ENaC subunits associate in mpkCCD cells. These studies examine a potential role for exosomes in the regulation of ENaC activity and examine a possible mechanism for communication from proximal tubule cells to distal tubule and collecting duct cells. 相似文献
64.
Carol L. Beaver Anja E. Williams Estella A. Atekwana Farag M. Mewafy Gamal Abdel Aal Lee D. Slater 《Geomicrobiology journal》2016,33(5):441-452
Recent studies suggest that magnetic susceptibility (MS) measurements can play an important role in identifying zones where microbial-mediated iron mineral transformations are occurring. Here we investigated the microbial community variations within zones of elevated MS in a petroleum hydrocarbon-contaminated aquifer near Bemidji, Minnesota, USA. Our main objective was to 1) identify the key microbial populations that may play a role in hydrocarbon degradation, 2) analyze which microbial populations could be connected to the elevated MS and 3) explore the use of non-destructive geophysical techniques as a tool to guide microbial sampling. Clone libraries based on the 16S rRNA gene revealed the presence of iron-reducing β-Proteobacteria in the vadose zone, whereas the free petroleum phase on the water table was characterized by a methanogenic consortium, in which the syntrophic δ-proteobacterium Smithella and the hydrogenotrophic Methanoregula predominated. Nonmetric multidimensional scaling (NMDS) found a close relationship between elevated MS values and the methanogenic hydrocarbon-degrading consortium. Our results suggest that magnetic susceptibility measurements can guide microbiologists to zones of active microbial biodegradation in aged petroleum spills. 相似文献
65.
66.
Endothelial progenitor cells (EPC) participate in revascularization and angiogenesis. EPC can be cultured in vitro from mononuclear cells of peripheral blood, umbilical cord blood or bone marrow; they also can be transdifferentiated from mesenchymal stem cells (MSC). We isolated EPCs from Wharton's jelly (WJ) using two methods. The first method was by obtaining MSC from WJ and characterizing them by flow cytometry and their adipogenic and osteogenic differentiation, then applying endothelial growth differentiating media. The second method was by direct culture of cells derived from WJ into endothelial differentiating media. EPCs were characterized by morphology, Dil-LDL uptake/UEA-1 immunostaining and testing the expression of endothelial markers by flow cytometry and RT-PCR. We found that MSC derived from WJ differentiated into endothelial-like cells using simple culture conditions with endothelium induction agents in the medium. 相似文献
67.
Eman Saad Elzanfaly Enas Abdel Hakim Amer Sara Abdel Basset Galal Hala Elsayed Zaazaa 《Luminescence》2019,34(1):64-69
A spectrofluorimetric method for the determination of eptifibatide is presented based on its native fluorescence. The type of solvent and the wavelength of maximum excitation and emission were carefully selected to optimize the experimental conditions. Under the specified experimental conditions, the linearities obtained between the emission intensity and the corresponding concentrations of eptifibatide were in the range 0.1–2.5 μg/ml for the calibration curve constructed for direct determination of eptifibatide in dosage form and 0.05–2.2 μg/ml for the calibration curve constructed in spiked human plasma with a good correlation coefficient (r > 0.99). The lower limit of quantification for the calibration curve constructed in human plasma was 0.05 μg/ml. Recovery results for eptifibatide in spiked plasma samples and in dosage form, represented as mean ± % RSD, were 95.17 ± 1.94 and 100.29 ± 1.33 respectively. The suggested procedures were validated according to the International Conference on Harmonization (ICH) guidelines for the direct determination of eptifibatide in its pure form and dosage form and United States Food and Drug Administration (US FDA) Guidance for Industry, Bioanalytical Method Validation for the assay of eptifibatide in human plasma. 相似文献
68.
Barbara Hernando Viki B. Swope Steven Guard Renny J. Starner Kevin Choi Ayesha Anwar Pamela Cassidy Sancy Leachman Ana Luisa Kadekaro Dorothy C. Bennett Zalfa A. Abdel‐Malek 《Pigment cell & melanoma research》2019,32(2):259-268
Coinheritance of germline mutation in cyclin‐dependent kinase inhibitor 2A (CDKN2A) and loss‐of‐function (LOF) melanocortin 1 receptor (MC1R) variants is clinically associated with exaggerated risk for melanoma. To understand the combined impact of these mutations, we established and tested primary human melanocyte cultures from different CDKN2A mutation carriers, expressing either wild‐type MC1R or MC1RLOF variant(s). These cultures expressed the CDKN2A product p16 (INK4A) and functional MC1R. Except for 32ins24 mutant melanocytes, the remaining cultures showed no detectable aberrations in proliferation or capacity for replicative senescence. Additionally, the latter cultures responded normally to ultraviolet radiation (UV) by cell cycle arrest, JNK, p38, and p53 activation, hydrogen peroxide generation, and repair of DNA photoproducts. We propose that malignant transformation of melanocytes expressing CDKN2A mutation and MC1RLOF allele(s) requires acquisition of somatic mutations facilitated by MC1R genotype or aberrant microenvironment due to CDKN2A mutation in keratinocytes and fibroblasts. 相似文献
69.
Loubna Tifarouine Faissal Aziz Abdallah El Abidi Nawal Hichami Salma Benmokhtar Bouabid Badaoui Hamid Rguibi Idrissi Mohamed Fekhaoui Abdelaziz Benhoussa 《Saudi Journal of Biological Sciences》2019,26(7):1682-1688
The influence of age and sex on the bioaccumulation of heavy metals in Apodemus sylvaticus was studied in Merja Zerga lagoon in northern Morocco. Five trace metal elements (Zn, Pb, Cr, Cu and Fe) were quantitatively analyzed by Varian AA 240 atomic absorption spectroscopy with graphite furnace in three organs (Liver, Kidney and Heart) from animals of different age and sex. The maximum metal level of the analyzed samples was recorded in adults and was limited to 46.62 μg/g for Pb and 35.1 μg/g for Cu, while it reached 22.69 μg/g, 7.59 μg/g and 6.78 μg/g for Cr, Zn and Fe, respectively. Highly significant differences were found for bioaccumulation of heavy metals according to animal ages and no significant differences were observed between the two sexes among the studied animals. Our results revealed also the existence of a strong correlation (r > 0.65) between the majority of biometric parameters and the trace element concentrations. In general, we found that age is a critical factor in estimating the level of heavy metal pollution. Other characteristics such as habitat, feeding habits and anti-predator behavior of the species need to be studied. 相似文献
70.
Nibedita Das Mst. Shahnaj Parvin Mahadi Hasan Masuma Akter Md. Sanowar Hossain G.M.Masud Parvez Ashish Kumar Sarker Md. Aziz Abdur Rahman Al Mamun Md. Ekramul Islam 《Biochemistry and Biophysics Reports》2022
Among the major constituents of Leea rubra (Family Vitaceae) leaves, phenolic and flavonoind compounds are most important for therapeutic purposes and the plant parts have been used in traditional medicine to treat several diseases for long. Thus, in order to scientifically confirm the traditional uses of the L. rubra leaves, the present study was designed to investigate the efficacy of the isolated flavones against AAPH induced oxidative damage to pUC19 DNA by gel electrophoresis and antineoplastic activity was evaluated on Ehrlich ascites carcinoma (EAC) bearing Swiss albino mice by evaluating percentage inhibition of cell growth, morphological changes of EAC cells and hematological parameters of the mice. The isolation was carried out by column chromatography and structure was revealed by 1H-NMR and 13C NMR. The result shows that, the isolated compound was identified as myricetin 4'-methoxy-3-O-α-l-rhamnopyranoside based on previously reported data. The isolated flavone effectively inhibited AAPH-induced oxidative damage to DNA; because it could inhibit the formation of circular and linear forms of the DNA. In anti-proliferative assay, 76% growth inhibition of EAC cells was observed as compare to the control mice (p<0.05) at a dose 100 mg/kg body weight. Thus the isolated flavone showed great importance as a possible therapeutic agent in preventing oxidative damage to DNA and the chronic diseases caused by such DNA damage, and can also become important in cancer chemotherapy. 相似文献