147 research outputs found

    Histamine release theory and roles of antihistamine in the treatment of cytokines storm of COVID-19

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    Histamine initiates abnormal immune response leading to cytokine storm and multi-organs failure. Thus, the use of antihistaminic medications could result in a significant immune modulation which may help in the treatment of cytokine storm of COVID-19. Future studies could compare H2R antagonists with those of steroid therapy in addition to the effect of combination therapy in relation to standard therapy

    Genetically modified animals for use in research and biotechnology

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    Transgenic animals are used extensively in the study of in vivo gene function, as models for human diseases and in the production of biopharmaceuticals. The technology behind obtaining these animals involves molecular biology techniques, cell culture and embryo manipulation; the mouse is the species most widely used as an experimental model. In scientific research, diverse models are available as tools for the elucidation of gene function, such as transgenic animals, knockout and conditional knockout animals, knock-in animals, humanized animals, and knockdown animals. We examined the evolution of the science for the development of these animals, as well as the techniques currently used in obtaining these animal models. We review the phenotypic techniques used for elucidation of alterations caused by genetic modification. We also investigated the role of genetically modified animals in the biotechnology industry, where they promise a revolution in obtaining heterologous proteins through natural secretions, such as milk, increasing the scale of production and facilitating purification, thereby lowering the cost of production of hormones, growth factors and enzyme

    Can Influenza Vaccine Modify COVID-19 Clinical Course?

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    This article is made available for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic

    Efficient removal of phenol compounds from water environment using Ziziphus leaves adsorbent

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    Β© 2020 Elsevier B.V. Industrial processes generate toxic organic molecules that pollute environment water. Phenol and its derivative are classified among the major pollutant compounds found in water. They are naturally found in some industrial wastewater effluents. The removal of phenol compounds is therefore essential because they are responsible for severe organ damage if they exist above certain limits. In this study, ground Ziziphus leaves were utilized as adsorbents for phenolic compounds from synthetic wastewater samples. Several experiments were performed to study the effect of several conditions on the capacity of the Ziziphus leaves adsorbent, namely: the initial phenol concentration, the adsorbent concentration, temperature, pH value, and the presence of foreign salts (NaCl and KCl). The experimental results indicated that the adsorption process reached equilibrium in about 4 h. A drop in the amount of phenol removal, especially at higher initial concentration, was noticed upon increasing the temperature from 25 to 45 Β°C. This reflects the exothermic nature of the adsorption process. This was also confirmed by the calculated negative enthalpy of adsorption (βˆ’64.8 kJ/mol). A pH of 6 was found to be the optimum value at which the highest phenol removal occurred with around 15 mg/g at 25 Β°C for an initial concentration of 200 ppm. The presence of foreign salts has negatively affected the phenol adsorption process. The fitting of the experimental data, using different adsorption isotherms, indicated that the Harkins-Jura isotherm model was the best fit, evident by the high square of the correlation coefficient (R2) values greater than 0.96. The kinetic study revealed that the adsorption was represented by a pseudo-second-order reaction. The results of this study offer a basis to use Ziziphus leaves as promising adsorbents for efficient phenol removal from wastewater

    CASZ1b, the Short Isoform of CASZ1 Gene, Coexpresses with CASZ1a during Neurogenesis and Suppresses Neuroblastoma Cell Growth

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    In Drosophila, the CASZ1 (castor) gene encodes a zinc finger transcription factor and is a neural fate-determination gene. In mammals, the CASZ1 gene encodes two major isoforms, CASZ1a with 11 zinc fingers and CASZ1b with 5 zinc fingers. CASZ1b is more evolutionally conserved since it is the only homologue found in drosophila and Xenopus. Our previous study showed that full length CASZ1 (CASZ1a) functions to suppress growth in neuroblastoma tumor. However, the function of CASZ1b isoform in mammals is unknown. In this study, realtime PCR analyses indicate that mouse CASZ1b (mCASZ1b) is dynamically expressed during neurogenesis. CASZ1b and CASZ1a co-exist in all the neuronal tissues but exhibit distinct expression patterns spatially and temporally during brain development. CASZ1b and CASZ1a expression is coordinately upregulated by the differentiation agent Retinoic Acid, as well as agents that modify the epigenome in neural crest derived neuroblastoma cell lines. In contrast CASZ1b is down regulated while CASZ1a is upregulated by agents that raise intracellular cAMP levels. CASZ1b and CASZ1a have no synergistic or antagonistic activities on the regulation of their target NGFR gene transcription. Specific restoration of CASZ1b in NB cells suppresses tumor growth in vitro and in vivo. Consistent with its function role, we find that low CASZ1b expression is significantly associated with decreased survival probability of neuroblastoma patients (p<0.02). This study indicates that although their mechanisms of regulation may be distinct, both CASZ1b and CASZ1a have largely redundant but critical roles in suppressing tumor cell growth

    Naturally Occurring Variants of Human Ξ‘9 Nicotinic Receptor Differentially Affect Bronchial Cell Proliferation and Transformation

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    Isolation of polyadenilated mRNA from human immortalized bronchial epithelial cell line BEP2D revealed the presence of multiple isoforms of RNA coded by the CHRNA9 gene for Ξ±9 nicotinic acetylcholine receptor (nAChR). BEP2D cells were homozygous for the rs10009228 polymorphism encoding for N442S amino acid substitution, and also contained mRNA coding for several truncated isoforms of Ξ±9 protein. To elucidate the biologic significance of the naturally occurring variants of Ξ±9 nAChR, we compared the biologic effects of overexpression of full-length Ξ±9 N442 and S442 proteins, and the truncated Ξ±9 variant occurring due to a loss of the exon 4 sequence that causes frame shift and early termination of the translation. These as well as control vector were overexpressed in the BEP2D cells that were used in the assays of proliferation rate, spontaneous vs. tobacco nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced cellular transformation, and tumorigenicity in cell culture and mice. Overexpression of the S442 variant significantly increased cellular proliferation, and spontaneous and NNK-induced transformation. The N442 variant significantly decreased cellular transformation, without affecting proliferation rate. Overexpression of the truncated Ξ±9 significantly decreased proliferation and suppressed cellular transformation. These results suggested that Ξ±9 nAChR plays important roles in regulation of bronchial cell growth by endogenous acetylcholine and exogenous nicotine, and susceptibility to NNK-induced carcinogenic transformation. The biologic activities of Ξ±9 nAChR may be regulated at the splicing level, and genetic polymorphisms in CHRNA9 affecting protein levels, amino acid sequence and RNA splicing may influence the risk for lung cancer

    Tumor Suppressor RASSF1A Promoter: p53 Binding and Methylation

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    Oncogenes and tumor suppressors work in concert to regulate cell growth or death, which is a pair of antagonist factors for regulation of tumorigenesis. Here we show promoter characteristic of tumor suppressor RASSF1A, which revealed a p53 binding site in the distal and a GC-rich region in the proximal promoter region of RASSF1A, in despite of TATA box-less. The GC-rich region, which is ∼300 bp upstream from the RASSF1A ATG, showed the strongest promoter activity in an assay of RASSF1A-driving GFP expression. Methylation analysis of the CpG island showed that 78.57% of the GC sties were methylated in testis tumor samples compared with methylation-less in normal testis. Hypermethylation of the GC-rich region is associated with RASSF1A silencing in human testis tumors. In addition, electrophoretic mobility shift assay indicated that p53 protein bound to the RASSF1A promoter. Further chromatin immunoprecipitation confirmed p53 binding to the RASSF1A. Moreover, p53 binding to the promoter down-regulated RASSF1A expression. These results suggest that p53 protein specifically binds to the RASSF1A promoter and inhibits its expression. Our results provide new insight into the mechanism of action of tumor suppressors and may be a starting point for development of new approaches to cancer treatment
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