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21.
Nasser Nassiri-Koopaei 《Biocatalysis and Biotransformation》2015,33(1):1-28
Steroids constitute a vital part of the active ingredients in pharmaceuticals and intermediates used to produce medicines, and their application in chemical and agrochemical fields is also valued. The complex stereochemistry of steroids requires attention to regio- and stereoselectivity of the reaction during preparation, and therefore, biocatalytic methods are appropriate for their production. This work reviews the recent application of fungi for the transformation of different steroid substrates, new biotransformation techniques, recently characterized reactions, and practical aspects, covering the period from 1990 to 2014. The future prospects of fungal biotechnology and biotransformation in the biopharmaceutical industry are also considered. 相似文献
22.
The focus of both clinical and basic studies on stem cells is increasing due to their potentials in regenerative medicine and cell-based therapies. Recently stem cells have been genetically modified to enhance an existing character in or to bring a new property to them. However, accomplishment of declared goals requires detailed knowledge about their molecular characteristics which could be achieved by genetic modifications mostly through nonviral transfection strategies. Capable of differentiating into multiple cells, human unrestricted somatic stem cells (hUSSCs) and human mesenchymal stem cells (hMSCs) seem to be suitable candidates for transfection approaches. Involvement of microRNAs (miRNAs) in many biological processes makes their transfection evaluation valuable. Herein we investigated the efficacy and toxicity of four typically used transfection reagents (Arrest-In, Lipofectamine 2000, Oligofectamine and HiPerfect) systematically to deliver fluorescent labeled-miRNA and Green Fluorescent Protein (GFP) expressing plasmid into hUSSCs and hMSCs. The authenticity of stem cells was verified by differentiation experiments along with flow cytometry of surface markers. Our study revealed that stemness properties of these stem cells were not affected by transient transfection. Moreover the ratios of cell viability and transfection efficiency in both analyzed stem cells were reversed. Considering cell viability, the highest fraction of GFP-expressing cells was obtained using Oligofectamine (~50%) while the highest transfection rate of miRNA was achieved by Lipofectamine 2000 (~90%). Moreover dependency of hMSCs to size of transfected nucleic acid and time-dependency of Oligofectamine and their affection on the yield of transfection were observed. Cytotoxicity assessments also showed that hUSSCs are sensitive to HiPerFect. In addition cells treated by Lipofectamine showed morphological changes. Representing the efficient nucleic acid transfection, our research facilitates comprehensive genetic modification of stem cells and demonstrates powerful approaches to understand stem cell molecular regulation mechanisms, which eventually improves nonviral cell-mediated gene therapy.
Electronic supplementary material
The online version of this article (doi:10.1007/s10616-012-9430-9) contains supplementary material, which is available to authorized users. 相似文献23.
Wamberg M Pedersen EB El-Brollosy NR Nielsen C 《Bioorganic & medicinal chemistry》2004,12(5):1141-1149
This paper reports the synthesis and the antiviral activities of a series of 6-arylvinyl substituted analogues of SJ-3366, a highly potent agent against HIV. The objective was to investigate whether substitution of the 6-arylketone with a 6-arylvinyl group could lead to an improved antiviral activity against HIV-1. The most active compounds 1-ethoxymethyl, 1-(2-propynyloxymethyl), and 1-(2-methyl-3-phenylallyloxymethyl) substituted 6-[1-(3,5-dimethylphenyl)vinyl]-5-ethyl-1H-pyrimidine-2,4-dione (5b, 16, and 18) showed activities against HIV-1 wild type in the range of Efavirenz, and moderate activities against Y181C and Y181C+K103N mutant strains were also observed. 相似文献
24.
Nasser S.A.M. Khalil 《Nucleosides, nucleotides & nucleic acids》2013,32(9):1277-1287
Synthetic routes toward the synthesis of some novel 1-(2,3,4-tri-O-acetyl-α-l-arabinopyranosyl)-azetidin-2-ones are described. Antimicrobial screening of three selected compounds revealed their activity against Bacillus subtilis and Escherichia coli. 相似文献
25.
Nasser M. Al-Daghri Hazim A. Al-Hazmi Abdulrahman Al-Ajlan Mohammad S. Masoud Abeer Al-Amro Amani Al-Ghamdi Abdullah M. Alnaami Omar S. Al-Attas Majed S. Alokail 《Saudi Journal of Biological Sciences》2018,25(4):710-714
Spexin (SPX) is a novel biomarker abundantly expressed in several animal and human tissues implicated in food intake and glucose control, respectively. As new roles for SPX are emerging, the present study explored for the first time, the associations of SPX to several cardiometabolic indices and inflammatory markers in pregnant women, a demographic not yet investigated with respect to SPX. A total of 117 Saudi women subdivided to those with gestational diabetes mellitus (GDM) (N?=?63) and those without (N?=?54) were included in this cross-sectional study. Anthropometry, glycemic, lipid, vitamin D, adipocytokines and inflammatory markers were measured consecutively at baseline and after the 2nd and 3rd trimesters. Age- and BMI adjusted comparisons revealed that levels of SPX were not significantly different in pregnant women with and without GDM. In all subjects, circulating levels of SPX showed modest associations with glucose (R?=?0.18; p?=?.08) and HOMA β (R?=??0.19; p?=?.09) as well as significant positive associations with total cholesterol (R?=?0.25; p?=?.02), LDL-cholesterol (R?=?0.25; p?=?.02), 25(OH)D (R?=?0.22; p?=?.04), albumin (R?=?0.30; p?<?.01) and IL1β (R?=?0.41; p?<?.01). Stepwise regression analysis also suggested that IL1β, leptin and albumin were the significant predictors of SPX. In summary, SPX levels modestly affect glucose and insulin sensitivity in pregnant women but is not associated with GDM and obesity. The significant association of SPX to ILβ warrants further investigation as to the role of SPX in immune modulation. 相似文献
26.
Behrooz Soltani Narges Bodaghabadi Gita Mahpour Nasser Ghaemi Majid Sadeghizadeh 《Biotechnology letters》2016,38(12):2081-2088
Objectives
To investigated the potential of a novel dendrosomal nanoformulation of curcumin (DNC) in blocking radiation-induced changes in irradiated human umbilical vein endothelial cells (HUVECs), and their adhesion to human THP-1 monocytoid cells.Results
Co60 gamma rays reduced viability, raised the expression of adhesion molecules, ICAM-1, VCAM-1 and E-selectin (mRNA and protein), augmented the adhesion of THP-1 cells to HUVECs, activated NF-κB binding, increased the release of pro-inflammatory cytokines (IL-6, IL-8 and MCP-1) and induced oxidative damage (reduced glutathione declined, while 8-OHdG and TBARS increased). 5 µM DNC significantly inhibited these radiation-induced changes, activated the Nrf-2 pathway, and effectively suppressed THP-1 adhesion to HUVECs, implicating p38 MAPK signaling.Conclusion
DNC treatment is a potential preventive method against inflammation and vascular damage from ionizing radiation.27.
Singh P Sachdeva S Raj R Kumar V Mahajan MP Nasser S Vivas L Gut J Rosenthal PJ Feng TS Chibale K 《Bioorganic & medicinal chemistry letters》2011,21(15):4561-4563
3-Azido-, 3-amino- and 3-(1,2,3-triazol-1-yl)-β-lactams were synthesized and evaluated for their antiplasmodial activity against four strains of Plasmodium falciparum and KB cells for their cytotoxicity profiles. The presence of a cyclohexyl substituent at N-1 and a phenyl group on the triazole ring markedly improved the activity profiles of triazole-tethered β-lactam exhibiting IC50 values of 1.13, 1.21 and 1.00 μM against 3D7, K1 and W2 strains respectively. 相似文献
28.
Mukhtar Ahmed Daoud Ali Abdel Halim Harrath Tajamul Hussain Nasser Al-Daghri Majed S. Alokail Ravindranath H. Aladakatti Mukhtar Ahmed G. Ghodesawar 《Comptes rendus biologies》2014,337(4):250-257
Boswellia papyrifera and Boswellia carterii diffuses smoke polluting air that adversely affects indoor environment that certainly harm human health. Therefore, this study aims at ascertaining the effect of these plants on gonadal hormones and molecular changes in rat spermatozoa. The animals were exposed to 4 g/kg body weight of B. papyrifera and B. carterii daily for 120 days along with suitable controls. Significant decreases in FSH, LH and testosterone levels were evidenced, along with a reduction of protein, sialic acid, and carnitine levels. In sperm physiology, sperm count, motility, speed decrease, whereas sperm anomalies increase. TEM observation indicates morphological changes in plasma and acrosomal membranes, cytoplasmic droplet in the tail region, vacuolated, and disorganization of the mitochondrial sheath. These findings demonstrate that B. papyrifera and B. carterii smoke affects the process of sperm formation and maturation, which indicates the detrimental effects of these plants on the reproductive system. 相似文献
29.
Diosque P Barnabé C Padilla AM Marco JD Cardozo RM Cimino RO Nasser JR Tibayrenc M Basombrío MA 《International journal for parasitology》2003,33(10):997-1003
A set of 65 Trypanosoma cruzi stocks from dogs, opossums, insect vectors and humans was isolated in a geographically restricted endemic area for Chagas' disease in Argentina and was analysed by multilocus enzyme electrophoresis for 15 loci. The results show that at least five multilocus genotypes (clonets) circulate in the study area, one belonging to T. cruzi IIe, one to T. cruzi IId and three clonets belonging to T. cruzi I; and they confirm the presence of these lineages in the country. The three clonets attributed to T. cruzi I were identical to each other for all loci except for Sod-2, where three different patterns were identified. These patterns suggest the presence of two homozygous genotypes and one heterozygous genotype. Our results also suggest association of clonet IIe with dogs, clonet IId with humans and the three T. cruzi I clonets with Didelphis albiventris. On the other hand, there was no significant association between Triatoma infestans and any particular clonet circulating in the area. These findings are consistent with the hypothesis of natural selection, from mixed populations of T. cruzi in vectors, toward more restricted populations in mammals. The epidemiological implications of the possible selection of different clonets by different mammal hosts and the significance of two homozygous genotypes and one heterozygous genotype for the Sod-2 locus are discussed. 相似文献
30.
The pecS regulatory locus negatively modulates the expression of many virulence genes in Erwinia chrysanthemi. This locus consists of two genes, pecS and pecM, divergently transcribed. Previous studies have shown that PecS down-regulates the expression of both pecSand pecMgenes and that PecM is required for full PecS activity. Computer-aided hydropathy analysis of PecM predicted the presence of between 8 to 10 potential transmembrane segments. We analyzed the membrane topology of PecM using the beta-lactamase gene fusion system and obtained the following unique characteristics. PecM contains 10 membrane spanning segments, with both the amino and carboxyl termini located in the cytoplasmic side of the inner membrane. The fourth periplasmic loop, which has a relatively long hydrophilic domain containing 17 amino acid residues, may play an important role in PecM function. The topological model obtained for PecM can be applied to PecM homologues in other bacteria. Measurement of the extrusion of the blue pigment indigoidine by the E. chrysanthemi derivative isogenic mutants pecS, pecM and pecS-pecM revealed that PecM is required for complete efflux of the pigment. Its relation to other efflux systems and its potential physiological role are discussed. 相似文献