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11.
Hasan Mirzahoseini Farideh Mehraein Eskandar Omidinia Mohamad R. Razavi 《World journal of microbiology & biotechnology》2004,20(2):161-165
Four different expression systems were developed for expression of the cDNA encoding human basic fibroblast growth factor (hbFGF), using Escherichia coli as host organism. The hbfgf structural gene was cloned into four expression vectors, pET-3a, pTrc99A, pPR37 and pKK223-3 differing only in their promoters, which were T7, trc, PR and tac respectively. Expression of the gene was induced by adding 0.5 mM (final concentration) of isopropyl--D-thio-galactopyranoside (IPTG) for the vectors carrying T7, trc and tac promoters or by a temperature shift from 30 to 42 °C for the vector carrying PR. The highest level of expression was observed in pET-1005 (a pET-3a derivative)/BL21 (DE3) system with 18.5 mg/l rhbFGF and the second high level expression was in pR37-1007 (pPR37 derivative) BL21 (DE3) system with 5 mg of rhbFGF/l. Since in the latter system a temperature shift was used for induction, 29% of the hbFGF was recovered as inclusion bodies in the insoluble cell fraction. The level of expression for the two other systems (pTrc-1006 and pKK-1008) was very low. 相似文献
12.
Bis‐ and Tetrakis(carboxylato)platinum(IV) Complexes with Mixed Axial Ligands – Synthesis,Characterization, and Cytotoxicity
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Björn R. Hoffmeister Michaela Hejl Mahsa S. Adib‐Razavi Michael A. Jakupec Markus Galanski Bernhard K. Keppler 《化学与生物多样性》2015,12(4):559-574
A series of twelve novel diamminetetrakis(carboxylato)platinum(IV) and 18 novel bis(carboxylato)dichlorido(ethane‐1,2‐diamine)platinum(IV) complexes with mixed axial carboxylato ligands was synthesized and characterized by multinuclear 1H‐, 13C‐, 15N‐, and 195Pt‐NMR spectroscopy. Their cytotoxic potential was evaluated (by MTT assay) against three human cancer cell lines derived from ovarian teratocarcinoma (CH1/PA‐1), lung (A549), and colon carcinoma (SW480). In the cisplatin‐sensitive CH1/PA‐1 cancer cell line, diamminetetrakis(carboxylato)platinum(IV) complexes showed IC50 values in the low micromolar range, whereas, for the most lipophilic compounds of the bis(carboxylato)dichlorido(ethane‐1,2‐diamine)platinum(IV) series, IC50 values in the nanomolar range were found. 相似文献
13.
Khadijeh Bijangi-Vishehsaraei Mohammad Reza Saadatzadeh Su Huang Michael P. Murphy Ahmad R. Safa 《Molecular and cellular biochemistry》2010,342(1-2):133-142
Cellular FLICE (FADD-like IL-1β-converting enzyme)-inhibitory protein (c-FLIP) is a major resistance factor for the tumor necrosis factor-related apoptosis-inducing ligand TRAIL and in drug resistance in human malignancies. c-FLIP is an antagonist of caspases-8 and -10, which inhibits apoptosis and is expressed as long (c-FLIPL) and short (c-FLIPS) splice forms. c-FLIP is often overexpressed in various human cancers, including breast cancer. Several studies have shown that silencing c-FLIP by specific siRNAs sensitizes cancer cells to TRAIL and anticancer agents. However, systemic use of siRNA as a therapeutic agent is not practical at present. In order to reduce or inhibit c-FLIP expression, small molecules are needed to allow targeting c-FLIP without inhibiting caspases-8 and -10. We used a small molecule inhibitor of c-FLIP, 4-(4-chloro-2-methylphenoxy)-N-hydroxybutanamide (CMH), and show that CMH, but not its inactive analog, downregulated c-FLIPL and c-FLIPS mRNA and protein levels, caused poly(ADP-ribose) polymerase (PARP) degradation, reduced cell survival, and induced apoptosis in MCF-7 breast cancer cells. These results revealed that c-FLIP is a critical apoptosis regulator that can serve as a target for small molecule inhibitors that downregulate its expression and serve as effective targeted therapeutics against breast cancer cells. 相似文献
14.
Khadijeh Zare Hossein Nazemiyeh Ali Movafeghi Mahmood Khosrowshahli Alireza Motallebi-Azar Mohammadreza Dadpour Yadollah Omidi 《Plant Cell, Tissue and Organ Culture》2010,100(2):157-164
An in vitro cell suspension culture of Echium italicum was established and assayed for the production of shikonin and alkannin derivatives. Callus tissues were induced from cotyledon
explants of the plant incubated onto the solidified B5 medium. A two-liquid-phase system suspension culture was then established
to elicit pigments of shikonin and alkannin derivatives using liquid paraffin. The presence of liquid paraffin efficiently
induced production of pigments in cultured cells. The production and/or accumulation of these compounds in the E. italicum cells was examined using fluorescence microscopy as the naphthoquinone molecules display autofluorescent properties. Phytochemical
analysis of the n-hexane extract of the medium was also carried out using preparative HPLC. The chemical structure of shikonin and alkannin
derivatives were characterized by UV, 1H-NMR, and 13C-NMR techniques. Based on our findings, this bioprocess engineering approach
resulted in induction of shikonin and alkannin derivatives, whereupon it may be recruited for production of these important
secondary metabolites. 相似文献
15.
Leila Hatami-Baroogh Shahnaz Razavi Hamid Zarkesh-Esfahani Marziyeh Tavalaee Somayeh Tanhaei Kamran Ghaedi Mohamad Reza Deemeh Farzaneh Rabiee Mohammad Hossein Nasr-Esfahani 《Reproductive biology and endocrinology : RB&E》2010,8(1):17
Background
Leptin, a 167 amino acid peptide hormone, profoundly effects reproduction exerting its biological effects via interaction with the leptin receptor (ObR) which is widely expressed on peripheral tissues. In this study, we have attempted to assess leptin receptor expression in the spermatozoa of fertile males and those diagnosed with male factor infertility; both at the mRNA or protein levels. 相似文献16.
Ali Amoozegar M Zahra Fatemi A Reza Karbalaei-Heidari H Reza Razavi M 《Microbiological research》2007,162(4):369-377
An extracellular protease was produced under stress conditions of high temperature and high salinity by a newly isolated moderate halophile, Salinivibrio sp. strain AF-2004 in a basal medium containing peptone, beef extract, glucose and NaCl. A modification of Kunitz method was used for protease assay. The isolate was capable of producing protease in the presence of sodium chloride, sodium sulfate, sodium nitrate, sodium nitrite, potassium chloride, sodium acetate and sodium citrate. The maximum protease was secreted in the presence of 7.5 to 10% (w/v) sodium sulfate or 3% (w/v) sodium acetate (4.6 U ml−1). Various carbon sources including glucose, lactose, casein and peptone were capable of inducing enzyme production. The optimum pH, temperature and aeration for enzyme production were 9.0, 32 °C and 220 rpm, respectively. The enzyme production corresponded with growth and reached a maximum level during the mid-stationary phase. Maximum protease activity was exhibited in the medium containing 1% (w/v) NaCl at 60 °C, with 18% and 41% activity reductions at temperature 50 and 70 °C, respectively. The optimum pH for enzyme activity was 8.5, with 86% and 75% residual activities at pH 10 and 6, respectively. The activity of enzyme was inhibited by EDTA. These results suggest that the protease secreted by Salinivibrio sp. strain AF-2004 is industrially important from the perspectives of its activity at a broad pH ranges (5.0–10.0), its moderate thermoactivity in addition to its high tolerance to a wide range of salt concentration (0–10% NaCl). 相似文献
17.
Type 1 diabetes (T1D) results from autoimmune-mediated loss of insulin-producing beta-cells. Recent findings suggest that the events controlling T1D development are not only immunological, but also neuronal in nature. In the non-obese diabetic (NOD) mouse model of T1D, a mutant sensory neuron channel, TRPV1, initiates chronic, progressive beta-cell stress, inducing islet cell inflammation. This novel mechanism of organ-specific damage requires a permissive, autoimmune-prone host, but ascribes tissue specificity to the local secretory dysfunction of sensory afferent neurons. In NOD mice, normalizing this neuronal function by administration of the neurotransmitter substance P clears islet cell inflammation, reduces insulin resistance and restores normoglycemia. Here, we discuss this neuro-immuno-endocrine model, its implications and the involvement of sensory neurons in other autoimmune disorders. These developments might provide novel neuronal-based therapeutic interventions, particularly in diabetes. 相似文献
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Predation rate and numerical response are basic to any investigation of predator–prey relationships and key components in the selection of predators for biological control. The density-dependent predation rate and numerical response of Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae) to varying densities (5, 10, 20, 40, 60 and 80) of third-instar Aphis craccivora (Koch) (Hemiptera: Aphididae), were studied in laboratory conditions [23±1°C, 70 ± 5% relative humidity (RH), and a photoperiod of 16:8 h L:D. Predation rate data were analysed using the age-stage, two-sex consumption rate software. Net consumption rate (C0) increased by increasing prey density. The lowest and highest net consumption rates were 20.75 and 190.8 prey nymphs at densities of 5 and 80 A. craccivora. The transformation rate from prey population to predator offspring (Qp) increased by increasing prey density. The reproductive numerical response, in terms of eggs laid, increased curvilinearly with increasing prey density. Females laid 121.375 ± 4.301 eggs when exposed to the highest prey density (80) and 52.5 ± 1.544 eggs at lowest prey density (5). It can be concluded that different densities of A. craccivora influenced the reproductive performance of A. aphidimyza in terms of predation rate and numerical response. 相似文献
20.
Z. E. Mousavi S. M. Mousavi S. H. Razavi Z. Emam-Djomeh H. Kiani 《World journal of microbiology & biotechnology》2011,27(1):123-128
In this research, production of probiotic pomegranate juice through its fermentation by four strains of lactic acid bacteria:
Lactobacillus plantarum, L. delbruekii, L. paracasei, L. acidophilus was examined. Fermentation was carried out at 30°C for 72 h under microaerophilic conditions. Microbial population, pH, titrable
acidity, sugar and organic acid metabolism were measured during the fermentation period and the viability of all strains was
also determined during the storage time at 4°C within 4 weeks. The results indicated that L. plantarum and L. delbruekii increased the pH sharply at the initial stages of fermentation and the sugar consumption was also higher in comparison with
other strains, better microbial growth was also observed for these two strains during fermentation. Citric acid, as a major
organic acid in pomegranate juice was significantly consumed by all probiotic lactic acid bacteria. L. plantarum and L. delbruekii showed higher viability during the storage time. Viable cells remained at their maximum level within 2 weeks but decreased
dramatically after 4 weeks. Pomegranate juice was proved to be a suitable media for production of a fermented probiotic drink. 相似文献