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101.
Smriti Panda Sankanika Roy Rohit K. Garg Gan Hui Jack Gorard Mayank Bhutada Yuanli Sun Sushma Bhatnagar Anant Mohan Lalit Dar Mao Liu 《Journal of medical virology》2022,94(1):272-278
Data pertaining to risk factor analysis in coronavirus disease 2019 (COVID-19) is confounded by the lack of data from an ethnically diverse population. In addition, there is a lack of data for young adults. This study was conducted to assess risk factors predicting COVID-19 severity and mortality in hospitalized young adults. A retrospective observational study was conducted at two centers from China and India on COVID-19 patients aged 20–50 years. Regression analysis to predict adverse outcomes was performed using parameters including age, sex, country of origin, hospitalization duration, comorbidities, lymphocyte count, and National Early Warning Score 2 (NEWS2) score at admission. A total of 420 patients (172 East Asians and 248 South Asians) were included. The predictive model for intensive care unit (ICU) admission with variables NEWS2 Category II and higher, diabetes mellitus, liver dysfunction, and low lymphocyte counts had an area under the curve (AUC) value of 0.930 with a sensitivity of 0.931 and a specificity of 0.784. The predictive model for mortality with NEWS2 Category III, cancer, and decreasing lymphocyte count had an AUC value of 0.883 with a sensitivity of 0.903 and a specificity of 0.701. A combined predictive model with bronchial asthma and low lymphocyte count, in contrast, had an AUC value of 0.768 with a sensitivity of 0.828 and a specificity of 0.719 for NEWS2 score (5 or above) at presentation. NEWS2 supplemented with comorbidity profile and lymphocyte count could help identify hospitalized young adults at risk of adverse COVID-19 outcomes. 相似文献
102.
V. Ravi Sonal Saxena Pragyan Swagatika Panda 《Indian journal of medical microbiology》2022,40(2):182-186
BackgroundSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a highly transmissible pathogenic coronavirus emerged in late 2019 causing a pandemic of acute respiratory disease, named ‘coronavirus disease 2019’ (COVID-19). It has spread fast all over the world posing an extraordinary threat to global public health. Along with SARS-CoV-2, there are seven human coronaviruses. Those causing mild diseases are the 229E, OC43, NL63 and HKU1, and the pathogenic ones are SARSCoV, MERS-CoV and SARS-CoV-2.ObjectiveThis review has highlighted the basic virology of SARS CoV-2 including its origin, structure, genomic characteristics, pathogenesis, immunological response and clinical manifestation along with the key difference of SARS CoV2 from the previous Coronaviruses.ContentCoronaviruses are spherical and enveloped with club-shaped spikes on the surface. It has a large positive sense, single stranded RNA genome within the nucleocapsid with a helical symmetry. It has been known to cause infection to innumerable mammalian hosts, like humans, cats, bats, civets, dogs, and camels. The viral genome contains four major structural proteins: the spike (S), membrane (M), envelope (E) and the nucleocapsid (N) protein encoded within the 3’ end of the genome. Virus binds to the host cell by the S protein with specific receptor. Following receptor binding, the virus enters host cell cytosol and there is fusion of the viral and cellular membranes followed by the translation of the viral genomic RNA. Following the viral replication and sub-genomic RNA synthesis, there is formation of the mature virus. The virions are then transported to the cell surface in vesicles and are released by exocytosis. 相似文献
103.
A number of secondary and tertiary amines bearing 2-chloro-6-methylquinoline were synthesized by nucleophilic substitution reaction of 3-(chloromethyl)-2-chloro-6-methylquinoline with substituted aromatic primary and secondary amines in presence of catalytic amount of triethylamine (TEA) and K(2)CO(3). All the compounds were characterized by combined use of IR, (1)H-NMR, (13)C-NMR, mass spectral data, and microanalyses. The newly synthesized quinolinyl amines were screened in vitro for their antifungal activity against Aspergillus niger MTCC 281, Aspergillus flavus MTCC 277, Monascus purpureus MTCC 369, Penicillium citrinum NCIM 768 and for antibacterial activity strains viz. Escherichia coli NCTC 10418, Staphylococcus aureus NCTC 65710, and Pseudomonas aeruginosa NCTC 10662 by agar diffusion technique. Results of the preliminary screening revealed that some of the compounds mainly those with electron withdrawing groups in the phenyl ring showed promising antifungal activity. 相似文献
104.
Natural products are regarded as vital key source of lead compounds for drug discovery due to their structural diversity and broad array of biological activities. Phenylpropanoid sucrose esters are naturally occurring compounds isolated from various plants and are structurally characterized by a sucrose core connected to one or more Ph-CH=CH-CO- moieties through an ester linkage. These compounds were extensively used in folk medicine and are found to possess many biological activities such as antitumor, antibacterial, antioxidant, antiviral, anti-inflammatory, neuro-protective and glycosidase inhibitory activities. This extensive review, which is the first of its kind on phenylpropanoid sucrose esters, aims to provide an up-to-date account of naturally occurring known phenylpropanoid sucrose esters with special focus on their sources, structures, biological and pharmacological activities. 相似文献
105.
106.
In the present study an attempt has been made to load Poly (Lactic-Co-glycolic acid) microspheres with hydroxyapatite (HA) and ofloxacin and propose the composite microspheres to be used as local drug delivery system with the drug releasing capability for periodontitis treatment. A modified single emulsion method has been used for the preparation of microspheres. Experiments were conducted to optimize the formulation by RSM-Box-Behnken Method, which is an independent quadratic design involving three or four independent variables against a pre determined set of dependant parameters. The particle size of composite microspheres was analyzed and the average size was found to be 22.05 μm. Photomicrographs and scanning electron micrographs showed that the composite microspheres are spherical in shape and porous in nature. The microbiological activity of optimized formulation was evaluated using strain: S. aureus-ATCC- 29213 and E. coli-ATCC-25922. In vivo/in situ toxicity evaluation of the formulation was assessed by MTT assay and the formulation was found to be biocompatible. 相似文献
107.
Ghosh A Choudhury A Das A Chatterjee NS Das T Chowdhury R Panda K Banerjee R Chatterjee IB 《Toxicology》2012,292(2-3):78-89
Earlier we had reported that irrespective of the source cigarette smoke (CS) contains substantial amounts of p-benzosemiquinone, which is readily converted to p-benzoquinone (p-BQ) by disproportionation and oxidation by transition metal containing proteins. Here we show that after CS-exposure, p-BQ-protein adducts are formed in the lungs as well as serum albumin of guinea pigs. We also show that serum of human smokers contains p-BQ-albumin adduct. It is known that human serum albumin (HSA) plays a very important role in binding and transport of a variety of ligands, including fatty acids and drugs. We show in vitro that p-BQ forms covalent adducts with free amino groups of all twenty amino acids as well as ?-amino groups of lysine residues of HSA in a concentration dependent manner. When HSA is incubated with p-BQ in the molar ratio of 1:1, the number of p-BQ incorporated is 1. At the molar ratio of 1:60, the number of p-BQ incorporated is 40. The formation of HSA-p-BQ adduct has been demonstrated by absorption spectroscopy, MALDI-MS and MALDI-TOF-TOF-MS analyses. Upon complexation with p-BQ, the secondary structure and conformation of HSA are altered, as evidenced by steady state and time-resolved fluorescence, circular dichroism, 8-anilino-1-napthalenesulfonic acid binding and differential scanning calorimetry. Alteration of the structure and conformation of HSA results in impairment of its ligand binding properties with respect to myristic acid, quercitin and paracetamol. This might be one of the reasons why transport and distribution of lipids and drugs are impaired in smokers. 相似文献
108.
Melissa J. Mulla rew G. Yu Ingrid Cardenas Seth Guller Britta Panda Vikki M. Abrahams 《American journal of reproductive immunology (New York, N.Y. : 1989)》2009,61(4):294-302
Problem: The cytoplasmic pattern recognition receptors, Nod1 and Nod2, are thought to be important for detecting intracellular bacteria. We have previously reported that first trimester trophoblast cells express Nod1 and Nod2, and that trophoblast Nod2 activation triggers an inflammatory response. The objectives of this study were to characterize the effects of Nod1 stimulation, and to determine the regulation of Nod1 and Nod2, in the trophoblast.
Method of Study: The effect of Nod1 activation on trophoblast cells was determined by analyzing the cytokine response following treatment with γ-D-glutamyl- meso -diaminopimelic acid (iE-DAP). The regulation of Nod1 and Nod2 expression by trophoblast cells was evaluated by RT-PCR.
Results: Treatment of trophoblast cells with iE-DAP significantly increased their production of cytokines and chemokines. In addition, Nod1 and Nod2 mRNA expression was upregulated following treatment of trophoblast cells with lipopolysaccharide (LPS), and this was significantly reduced by the presence of a NFκB inhibitor and a TLR4-dominant negative (DN).
Conclusion: This study demonstrates that LPS, through TLR4, increases trophoblast expression of Nod1 and Nod2 via the NFκB pathway; and that Nod1 is functional in the trophoblast. These findings suggest that extracellular recognition of bacterial LPS by TLR4 may prime the trophoblast in preparation for its cytoplasmic recognition of, and response to, bacterial peptides through the Nod proteins. 相似文献
Method of Study: The effect of Nod1 activation on trophoblast cells was determined by analyzing the cytokine response following treatment with γ-D-glutamyl- meso -diaminopimelic acid (iE-DAP). The regulation of Nod1 and Nod2 expression by trophoblast cells was evaluated by RT-PCR.
Results: Treatment of trophoblast cells with iE-DAP significantly increased their production of cytokines and chemokines. In addition, Nod1 and Nod2 mRNA expression was upregulated following treatment of trophoblast cells with lipopolysaccharide (LPS), and this was significantly reduced by the presence of a NFκB inhibitor and a TLR4-dominant negative (DN).
Conclusion: This study demonstrates that LPS, through TLR4, increases trophoblast expression of Nod1 and Nod2 via the NFκB pathway; and that Nod1 is functional in the trophoblast. These findings suggest that extracellular recognition of bacterial LPS by TLR4 may prime the trophoblast in preparation for its cytoplasmic recognition of, and response to, bacterial peptides through the Nod proteins. 相似文献
109.
110.