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121.
Ghasemi Y Rasoul-Amini S Naseri AT Montazeri-Najafabady N Mobasher MA Dabbagh F 《Prikladnaia biokhimiia i mikrobiologiia》2012,48(2):150-168
With the decrease of fossil based fuels and the environmental impact of them over the planet, it seems necessary to seek the sustainable sources of clean energy. Biofuels, is becoming a worldwide leader in the development of renewable energy resources. It is worthwhile to say that algal biofuel production is thought to help stabilize the concentration of carbon dioxide in the atmosphere and decrease global warming impacts. Also, among algal fuels' attractive characteristics, algal biodiesel is non toxic, with no sulfur, highly biodegradable and relatively harmless to the environment if spilled. Algae are capable of producing in excess of 30 times more oil per acre than corn and soybean crops. Currently, algal biofuel production has not been commercialized due to high costs associated with production, harvesting and oil extraction but the technology is progressing. Extensive research was conducted to determine the utilization of microalgae as an energy source and make algae oil production commercially viable. 相似文献
122.
Maryam Ghasemi Burkhard A. Hense Hermann J. Eberl Christina Kuttler 《Bulletin of mathematical biology》2018,80(7):1736-1775
We present a mathematical model of biofilm response to antibiotics, controlled by a quorum sensing system that confers increased resistance. The model is a highly nonlinear system of partial differential equations that we investigate in computer simulations. Our results suggest that an adaptive, quorum sensing-controlled, mechanism to switch between modes of fast growth with little protection and protective modes of slow growth may confer benefits to biofilm populations. It enhances the formation of micro-niches in the inner regions of the biofilm in which bacteria are not easily reached by antibiotics. Whereas quorum sensing inhibitors can delay the onset of increased resistance, their advantage is lost after up-regulation. This emphasizes the importance of timing for treatment of biofilms with antibiotics. 相似文献
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124.
Sabouri Atefeh Afshari Reza Raiesi Tayebeh Babaei Raouf Haniyeh Nasiri Elham Esfahani Masoud Kafi Ghasemi Ali Kumar Arvind 《Molecular biology reports》2018,45(5):1037-1053
Molecular Biology Reports - Drought is one of the biggest challenges for rice (Oryza sativa L.) production in rainfed areas. Developing “aerobic rice” cultivars could be a valuable... 相似文献
125.
Kate E. Slessor Jeanette E. Stok Sonia M. Cavaignac David B. Hawkes Younes Ghasemi James J. De Voss 《Bioorganic chemistry》2010,38(2):81-86
The first steps in the biodegradation of 1,8-cineole involve the introduction of an alcohol and its subsequent oxidation to a ketone. In Citrobacter braakii, cytochrome P450cin has previously been demonstrated to perform the first oxidation to produce (1R)-6β-hydroxycineole. In this study, we have cloned cinD from C. braakii and expressed the gene product, which displays significant homology to a number of short-chain alcohol dehydrogenases. It was demonstrated that the gene product of cinD exhibits (1R)-6β-hydroxycineole dehydrogenase activity, the second step in the degradation of 1,8-cineole. All four isomers of 6-hydroxycineole were examined but only (1R)-6β-hydroxycineole was converted to (1R)-6-ketocineole. The (1R)-6β-hydroxycineole dehydrogenase exhibited a strict requirement for NAD(H), with no reaction observed in the presence of NADP(H). The enzyme also catalyses the reverse reaction, reducing (1R)-6-ketocineole to (1R)-6β-hydroxycineole. During this study the N-terminal His-tag used to assist protein purification was found to interfere with NAD(H) binding and lower enzyme activity. This could be recovered by the addition of Ni2+ ions or proteolytic removal of the His-tag. 相似文献
126.
Asghar Ghasemi Saleh Zahediasl Leila Syedmoradi Fereidoun Azizi 《Biological trace element research》2010,136(1):18-25
This study aims at determining possible association between serum magnesium (Mg) concentrations and metabolic syndrome (MetS)
in elderly subjects. Subjects were 137 men and women aged 60 to 90 years, selected from among participants of the Tehran Lipid
and Glucose Study after excluding those taking medications for hypertension and dyslipidemia. Serum Mg levels were measured
by atomic absorption spectrometry and MetS was defined according to ATP III criteria. The overall prevalence of MetS was 43.8%.
Among MetS components, only plasma glucose showed a negative correlation with serum Mg concentrations (r = −0.194, p = 0.024). Subjects with MetS had significantly lower serum Mg concentrations compared with non-MetS ones (2.09 ± 0.03 vs.
2.18 ± 0.03 mg/dL, p = 0.033) even after adjustments with MetS components except for hyperglycemia (2.04 ± 0.06 vs. 2.20 ± 0.05 mg/dL, p = 0.011). However, after adjustment for hyperglycemia per se or along with the other MetS components, the significant difference
between serum Mg levels in subjects with and without MetS disappeared. In conclusion, serum Mg level is diminished in elderly
subjects with MetS, and hyperglycemia may play dominant role in this decrease; however, the results do not clarify whether
the low serum Mg level is a consequence of hyperglycemia or is a risk factor contributing to its development. 相似文献
127.
Asghar Ghasemi Saleh Zahediasl Fereidoun Azizi 《Biological trace element research》2010,138(1-3):99-106
This study aims at determining the reference values for serum magnesium (Mg) concentrations in Iranian adults. Serum Mg level was measured using flame atomic absorption spectrometry in 491 subjects (233 men and 258 women), aged 20-50 years, randomly selected from a population-based study. The International Federation of Clinical Chemistry guidelines and the robust method were used for determining the reference values. The 95% reference values for serum Mg concentration were 1.83-2.49, 1.79-2.48, and 1.83-2.55 mg/dL in men, women, and total population, respectively. The prevalences of hypo- and hypermagnesemia, according to the reference values obtained in the current study, were 2.5% and 4.0%, respectively. In conclusion, this study reports serum Mg reference values based on current standards in a large healthy population of young Iranian adults. 相似文献
128.
Members of the polychaete family Nereididae do not occur naturally in the Caspian Sea but are documented intentional human introductions that commenced in 1939. However, the identity of the species involved has been uncertain; material has been identified as both Alitta succinea and Hediste diversicolor. In this study, we confirm the presence of both species in the Caspian Sea. We discuss the distribution of both species, based on tolerance to physical factors, especially salinity. Although establishment of this partially predatory Nereidid, as a food reservoir could facilitate the recreation of commercially exploited fish stock, the consequences for native benthic communities are unclear and may be subject to unforeseen negative impacts. 相似文献
129.
l-Asparaginase is an anti-neoplastic drug used in lymphoblastic leukemia chemotherapy. Nowadays, this enzyme derived from bacterial
sources, mostly l-asparaginase II from Escherichia coli and in lesser amount l-asparaginase of Erwinia sp. has medical utilization. The long-term usage of these agents leads to allergic reactions and new asparaginase with new
immunological characteristics is required. Halophilic bacteria might contain l-asparaginase with novel immunological properties that can be used in hypersensitive patients. In this experiment, we have
screened moderate Halophilic bacteria for l-asparaginase production ability and showed that Halophilic bacteria produce intra- and extracellular l-asparaginase. Bacillus sp. BCCS 034 was found to produce the highest l-asparaginase (1.64 IU/ml supernatant) extracellularly. 相似文献
130.
Marzieh Ghasemi Mahnaz Azarnia Mansoor Jamali Ghadireh Mirabolghasemi Shahram Nazarian Mohammad Mehdi Naghizadeh Majid Rajabi Yaser Tahamtani 《Tissue & cell》2014
Inflammation and oxidation are two important factors in the pathogenesis of liver. Ephedra pachyclada (EP) is a traditional medical herb that has anti-inflammatory and anti-oxidant activities. During this study, anti-oxidant activities of the EP extract was measured in vitro by 2,2′- diphenyl-1-picrylhydrazyl (DPPH) and β-Carotene bleaching assays. Then, we examined possible in vivo hepatoprotective effects of EP extract on mouse models of carbon tetrachloride (CCl4)-induced chronic and acute liver failure. To produce mouse models of chronic and acute liver injuries, male SW1 mice were interaperitoneally injected with 1 ml/kg body weight (bw) CCl4 biweekly for 42 days and a single dose of 2 ml/kg bw, respectively. In the experimental groups, mouse models were treated with low (140 mg/kg bw) and high (1400 mg/kg bw) doses of the EP extract. Olive oil and water treated mice were considered as controls during model derivation and EP extract treatment respectively. The results showed the antioxidant activity of EP extract and a significant reduction of all parameters of CCl4-induced liver injury such as relative liver weight, necrosis, fibrosis, inflammation, and serum aspartate transaminase (AST) and alanine aminotransferase (ALT) in mouse models of acute and chronic liver injury treated with EP extract. Therefore, EP induces its hepatoprotective effects probably by suppressing oxidative stress and inhibit inflammation in the liver and is able to protect the liver against CCl4-induced acute and chronic injuries. 相似文献