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91.
Ali Dehestani Kamal Kazemitabar Gholamreza Ahmadian Nadali Babaeian Jelodar Ali Hatef Salmanian Mehdi Seyedi Heshmat Rahimian Seyedhadi Ghasemi 《Biotechnology letters》2010,32(4):539-546
The Bacillus pumilus SG2 chitinase gene (ChiS) and its truncated form lacking chitin binding (ChBD) and fibronectin type III (FnIII) domains were transformed to Arabidopsis plants and the expression, functionality and antifungal activity of the recombinant proteins were investigated. Results showed
that while the two enzyme forms showed almost equal hydrolytic activity toward colloidal chitin, they exhibited a significant
difference in antifungal activity. Recombinant ChiS in plant protein extracts displayed a high inhibitory effect on spore
germination and radial growth of hyphae in Alternaria brassicicola, Fusarium graminearum and Botrytis cinerea, while the activity of the truncated enzyme was strongly abolished. These findings demonstrate that ChBD and FnIII domains
are not necessary for hydrolysis of colloidal chitin but play an important role in hydrolysis of chitin–glucan complex of
fungal cell walls. Twenty microgram aliquots of protein extracts from ChiS transgenic lines displayed strong antifungal activity
causing up to 80% decrease in fungal spore germination. This is the first report of a Bacillus pumilus chitinase expressed in plant system. 相似文献
92.
Serum concentration of nitric oxide metabolites (NOx) is associated with cardiovascular disease risk factors in pediatrics. The aim of this study was to determine sex- and age-specific reference ranges for serum NOx concentrations in pediatrics. Serum NOx levels were measured in 401 subjects (189 boys and 212 girls), aged 4–19 years, using the Griess method. Study subjects selected from participants of Tehran lipid and glucose study, an ongoing cohort study aimed at determining of noncommunicable disease risk factors among Tehranian subjects. The International Federation of Clinical Chemistry guidelines and the robust method were used for determining reference values for sample sizes greater or less than 120 respectively. The 95% reference values for serum NOx concentrations were 13.6–69.2, 11.4–66.0, and 12.2–69.4 μmol/L in boys, girls, and total population respectively. The upper limit of serum NOx was 28% lower in otherwise healthy overweight and obese boys while it was 6% higher in overweight and obese girls, for both groups compared to their corresponding normal weight subjects. In conclusion, this study, for the first time, reports reference values for serum NOx levels in healthy children and adolescents. 相似文献
93.
Y. Ghasemi S. Rasoul-Amini A. T. Naseri N. Montazeri-Najafabady M. A. Mobasher F. Dabbagh 《Applied Biochemistry and Microbiology》2012,48(2):126-144
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
94.
Yari Maryam Ghoshoon Mohammad Bagher Nezafat Navid Ghasemi Younes 《International journal of peptide research and therapeutics》2020,26(3):1583-1591
International Journal of Peptide Research and Therapeutics - Erwinia chrysanthemi asparaginase is an important drug used in cancer treatment, especially in acute lymphoblastic leukemia (ALL).... 相似文献
95.
Victoria R. Vayer Lincoln R. Larson M. Nils Peterson Kangjae Jerry Lee Richard Von Furstenberg Daniel Y. Choi Kathryn Stevenson Adam A. Ahlers Christine Anhalt-Depies Taniya Bethke Jeremy Bruskotter Christopher J. Chizinski Brian Clark Ashley A. Dayer Benjamin Ghasemi Larry Gigliotti Alan Graefe Kris Irwin Samuel J. Keith Matt Kelly Gerard Kyle Elizabeth Metcalf Wayde Morse Mark D. Needham Neelam Poudyal Michael Quartuch Shari Rodriguez Chelsie Romulo Ryan L. Sharp William Siemer Matt Springer Richard Stedman Taylor Stein Tim Van Deelen Jason Whiting Richelle L. Winkler Kyle Maurice Woosnam 《The Journal of wildlife management》2021,85(5):1017-1030
Declining participation in hunting, especially among young adult hunters, affects the ability of state and federal agencies to achieve goals for wildlife management and decreases revenue for conservation. For wildlife agencies hoping to engage diverse audiences in hunter recruitment, retention, and reactivation (R3) efforts, university settings provide unique advantages: they contain millions of young adults who are developmentally primed to explore new activities, and they cultivate a social atmosphere where new identities can flourish. From 2018 to 2020, we surveyed 17,203 undergraduate students at public universities across 22 states in the United States to explore R3 potential on college campuses and assess key demographic, social, and cognitive correlates of past and intended future hunting behavior. After weighting to account for demographic differences between our sample and the larger student population, 29% of students across all states had hunted in the past. Students with previous hunting experience were likely to be white, male, from rural areas or hunting families, and pursuing degrees related to natural resources. When we grouped students into 1 of 4 categories with respect to hunting (i.e., non-hunters [50%], potential hunters [22%], active hunters [26%], and lapsed hunters [3%]), comparisons revealed differences based on demographic attributes, beliefs, attitudes, and behaviors. Compared to active hunters, potential hunters were more likely to be females or racial and ethnic minorities, and less likely to experience social support for hunting. Potential hunters valued game meat and altruistic reasons for hunting, but they faced unique constraints due to lack of hunting knowledge and skills. Findings provide insights for marketing and programming designed to achieve R3 objectives with a focus on university students. © 2021 The Wildlife Society. 相似文献
96.
97.
Fahimeh Ramezani Tehrani Mahsa Noroozzadeh Saleh Zahediasl Asghar Ghasemi Abbas Piryaei Fereidoun Azizi 《PloS one》2013,8(8)
The reproductive system is extremely susceptible to environmental insults, for example exogenous steroids during gestational development and differentiation. Experimental induction of androgen excess during prenatal life in female animal models reprograms their reproductive physiology, however the fetal programming of the male reproductive system by androgen excess has not been well studied. We aimed to determine the effect of prenatal exposure of two different doses of testosterone on different gestational days, on the male reproductive system using a rat model. Sixteen pregnant rats were randomly divided into two experimental groups and two control groups. Experimental group І were subcutaneously injected with 3 mg free testosterone on gestational days 16-19 and its controls received solvent for that time; experimental group П were subcutaneously injected with 20 mg free testosterone on day 20 of gestational period and its controls received solvent at the same time. The reproductive system morphology and function of 32 male offspring of these study groups were compared at days 6-30-60 of age and after puberty. The anogenital distance of the male offspring of both experimental groups had no significant differences on the different days of measurement, compared with controls. In the offspring of experimental group І, the testes weight, number of Sertoli, Spermatocyte and Spermatid cells, sperm count and motility and the serum concentration of testosterone after puberty were significantly decreased; except for reduction of sperm motility (p< 0.01), the other effects were not observed in the offspring of experimental group ІІ. In summary, our data show that prenatal exposure of male rat fetuses to excess testosterone disrupted reproductive function, an effect highly dependent on the time, duration and level of exposure. It seems that the reproductive system in individuals exposed to high levels of androgens during fetal life should be evaluated at puberty and likely to be treated. 相似文献
98.
Soleiman Ghasemi 《Archives Of Phytopathology And Plant Protection》2013,46(13):1552-1563
Fermentation optimisation to achieve high biomass and high efficiency of a biocontrol product is millstone in biocontrol sciences. Here, a Placket–Burman design used for comparison and screening of some environmental factors that are effective on bacterial biomass of Bacillus subtilis UTB96. A response surface methodology used to determine the optimal points for three factors including pH, temperature and C/N ratio where the biomass is high. The results of response surface methodology application showed that the optimum conditions for maximum production of biomass in the medium occurs at pH 7, temperature 30?°C and C/N ratio of 23:1. Bacteria derived from optimised conditions either from laboratory or semi-industrial bioreactors, showed a considerable increase in biomass and also, their antagonistic activity against Phytophthora drechsleri in a plate assay. However, optimisation of culture medium in a laboratory bioreactor decreased the antagonistic activity against Aspergillus flavus. Application of the optimised culture medium in both semi-industrial and laboratory bioreactors reduced the length of the lag phase of bacterial growth. 相似文献
99.
Sedigheh Zakeri Mandana Afsharpad Faezeh Ghasemi Ahmad Raeisi Qutbuddin Kakar Hoda Atta Navid Dinparast Djadid 《Experimental parasitology》2011,(1):167-172
The main aim of the present study was to investigate the frequency of SNPs-haplotypes of dhfr and dhps genes associated to sulfadoxine–pyrimethamine (SP) resistance in Plasmodium vivax clinical isolates circulating in a malaria endemic area, Pakistan. All 164 collected isolates were analyzed for SNPs-haplotypes at positions 13, 33, 57, 58, 61, 117 and 173 of pvdhfr and 383 and 553 of pvdhps genes using PCR–RFLP methods. All examined isolates were found to carry wild-type amino acids at positions 13, 33, 57, 61 and 173, while 58R and 117N mutations were detected among 15.2% and 53.6% of isolates, respectively. Based on the size polymorphism of pvdhfr genes at repeat region, type B (79.3%) was the most prevalent variant. The combination of pvdhfr and pvdhps haplotypes demonstrated nine distinct haplotypes. The three most prevalent haplotypes were I13P33F57S58T61S117I173/A383A553 (43.9%), I13P33F57S58T61N117I173/A383A553 (33.6%) and I13P33F57R58T61N117I173/A383A553 (12.2%). The presence of mutant haplotypes is worrying and indicates the emergence of drug tolerant/resistant P. vivax isolates in Pakistan in near future. 相似文献
100.
Ghadami SA Khodarahmi R Ghobadi S Ghasemi M Pirmoradi S 《Biophysical chemistry》2011,159(2-3):311-320
The misfolding and extracellular amyloid deposition of specific proteins are associated with a large family of human pathologies, often called protein conformational diseases. Despite the many efforts expended to characterize amyloid formation in vitro, there is no deep knowledge about the environment (in which aggregation occurs) as well as mechanism of this type of protein aggregation. Recently, β-lactoglobulin (β-lg) was driven toward amyloid aggregation under specific extreme conditions. In the present study, citraconylation was employed to neutralize the charges on accessible lysine residues of β-lg and different approaches such as turbidimetry, thermodynamic analysis, extrinsic fluorimetry and theoretical studies have been successfully used to compare the different behaviors of the native and modified proteins. Kinetic analyses of native β-lg aggregation showed a gradual development of turbidity, whereas the modified β-lg displayed an increased propensity toward aggregation. Our results clearly demonstrated that the stability of modified β-lg is markedly reduced, compared to the native one. Using of TANGO and WALTZ algorithms (as well as modelling softwares) which describe aggregation tendencies of different parts of a protein structure, we suggested critical importance of some of the lysine residues in the aggregation process. The results highlighted the critical role of protein stability and elucidated the underlying role of hydrophobic/electrostatic interactions in lactoglobulin-based experimental system. 相似文献