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Heli H Amani M Moosavi-Movahedi AA Jabbari A Floris G Mura A 《Bioscience, biotechnology, and biochemistry》2008,72(1):29-36
The electrochemical behavior of redox centers in the active site of amine oxidases from lentil seedlings and Euphorbia characias latex was investigated using a mercury film electrode. Tyrosine-derived 6-hydroxydopa quinone (TPQ) and copper ions in the active site are redox centers of these amine oxidases. The enzymes undergo two reduction processes at negative potentials related to the reduction of the TPQ cofactor to the corresponding hydroquinones and the reduction of copper ions, (Cu(II)-->Cu(I)). Copper depleted enzymes, prepared by reduction with dithionite followed by dialysis against cyanide, undergo only one reduction process. Nyquist diagrams, recorded at potentials corresponding to the reduction of cofactors as dc-offset, represent charge transfer impedance followed by a Warburg-type line at low frequencies, indicating the occurrence of a diffusion controlled process in the rate-limiting step of the reduction process. 相似文献
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Parvin Salehi Shanjani Mohsen Mardi Leila Pazouki Marianna Hagidimitriou Damiano Avanzato S. Mostafa Pirseyedi Mohammad Reza Ghaffari S. Mojtaba Khayam Nekoui 《Tree Genetics & Genomes》2009,5(3):447-458
Knowledge of pistachio genetic diversity is necessary for the formulation of appropriate management strategies for the conservation
of these species. We analysed amplified fragment length polymorphisms in a total of 216 pistachio accessions, which included
seven populations from three wild species (Pistacia vera, Pistacia khinjuk and Pistacia atlantica subsp. kurdica) and most of the important cultivars from Iran, together with some foreign cultivars. High levels of genetic diversity were
detected within the Iranian cultivars, and they showed a clear separation from foreign cultivars, as revealed by unweighted
pair group method with arithmetic averaging and supported by analysis of molecular variance. The lowest amount of polymorphism
was observed in P. atlantica subsp. kurdica, which showed the lowest number of total bands as compared to the other species. This revealed strong genetic erosion of
P. atlantica subsp. kurdica, which reflected a severe decline in habitat and over-exploitation. Based on these findings, strategies are proposed for
the genetic conservation and management of pistachio species and cultivars. 相似文献
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Mojtaba Tabatabaei Yazdi Gholamreza Zarrini Elham Mohit Mohammad Ali Faramarzi Neda Setayesh Navid Sedighi Farzaneh Aziz Mohseni 《World journal of microbiology & biotechnology》2006,22(4):325-330
Summary One hundred and sixty-five strains of microorganisms with the ability to grow in a medium containing uric acid as a major
source of nitrogen were isolated from soil samples during a screening program. Among them, a zygomycete fungus with well-developed
columellae was recognized to produce high levels of the enzyme in a short time. Classification of the isolated fungus was
carried out according to the morphological and culture characteristics of the organism, and it was identified as Mucor hiemalis. The fungus was able to produce an intracellular urate oxidase in a fermentation medium mainly containing uric acid. Optimized
composition of the medium consisted of (l−1 of distilled water) uric acid, 7.0 g; maltose, 6.0 g; Vogel stock solution, 20 and 1 ml of 0.5 M copper sulphate. The optimum
pH and temperature for uricase production in the optimized medium were pH 6 and 30 °C, respectively. 相似文献
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Single-walled carbon nanotube-modified carbon–ceramic electrode (SWCNT/CCE) was employed for the simultaneous determination of acetaminophen (APAP) and ascorbic acid (AA). The SWCNT/CCE displayed excellent electrochemical catalytic activities toward APAP and AA oxidation compared with bare CCE. In the differential pulse voltammetry technique, both AA and APAP gave sensitive oxidation peaks at −62 and 302 mV versus saturated calomel electrode, respectively. Under the optimized experimental conditions, APAP and AA gave linear responses over ranges of 0.2 to 150.0 μM (R2 = 0.998) and 5.0 to 700.0 μM (R2 = 0.992), respectively. The lower detection limits were found to be 0.12 μM for APAP and 3.0 μM for AA. The investigated method showed good stability, reproducibility, and repeatability as well as high recovery in pharmaceutical and biological samples. 相似文献
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Mohammad Ali Assarehzadegan Mojtaba Sankian Farahzad Jabbari Mohsen Tehrani Reza Falak AbdolReza Varasteh 《Molecular biology reports》2011,38(1):65-73
Salsola kali pollen is a common cause of pollinosis during summer and early fall in desert and semi-desert regions. The aim of this study
was the identification and characterization of Sal k 3, a new allergen from S. kali pollen. S. kali pollen extract was fractionated by SDS-PAGE and the allergenic profile was determined by IgE-immunoblotting using twelve
S. kali allergic patients. Protein identification was carried out by the means of mass spectrometry. Using degenerated primers, two
DNA fragments encoding N- and C-terminal domain of Sal k 3 were amplified by PCR, then cloned into the PTZ57R/T vector and
sequenced. The open reading frame of Sal k 3 fragments were subcloned in the pET-32b(+) vector, expressed in E. coli, and purified by Ni2+ affinity chromatography. The IgE-binding capacity of rSal k 3 fragments was then studied by IgE-immunoblotting, inhibition
assays, and skin prick tests. A 45-kDa allergen was identified as a fragment of the cobalamin-independent methionine synthase
(MetE) by mass spectrometry and was detected in the sera of 8/12 (66.6%) of S. kali allergic patients. Moreover, inhibition assays demonstrated that the purified rSal k 3 fragments were similar to their counterparts
in the crude extract. Sal k 3 represents a new allergen of S. kali pollen and seems to be an important allergenic compound in S. kali pollen. 相似文献
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Panjehpour M Karami-Tehrani F 《The international journal of biochemistry & cell biology》2004,36(8):1502-1509
A3 adenosine receptor agonists have been reported to influence cell death and survival. Here we report the effects of an A3 adenosine receptor agonist, IB-MECA, on the cell growth of human breast cancer cell lines, MCF-7 (estrogen receptor positive) and MDA-MB468 (estrogen receptor negative). Therefore, this study was aimed to investigate the expression and possible action of A3 receptor in the human breast cancer cell lines. IB-MECA, at 1-100 microM, resulted in a significant cell growth inhibition (P < 0.05) which reached the maximum at 48 h, in the cell lines. In both cell lines, agonist-induced effects were antagonized by pretreatment with a selective A3 adenosine receptor antagonist, MRS1220. Using RT-PCR method, further confirmation was provided by the presence of mRNA of A3 receptor in the cells. In addition, IB-MECA was able to inhibit forskolin-stimulated cAMP levels, which indicate the functional form of A3 receptor on the cell surface of these breast cancer cell lines. These results suggest that the inhibitory effect of IB-MECA on the growth of human breast cancer cell lines is mediated through activation of A3 adenosine receptor. 相似文献
58.
Chaitanya Pant Abhishek Deshpande Mojtaba Olyaee Michael P. Anderson Anas Bitar Marilyn I. Steele Pat F. Bass III Thomas J. Sferra 《PloS one》2014,9(5)
Background
Single-center studies suggest an increasing incidence of acute pancreatitis (AP) in children. Our specific aims were to (i) estimate the recent secular trends, (ii) assess the disease burden, and (iii) define the demographics and comorbid conditions of AP in hospitalized children within the United States.Methods
We used the Healthcare Cost and Utilization Project Kids’ Inpatient Database, Agency for Healthcare Research and Quality for the years 2000 to 2009. Extracted data were weighted to generate national-level estimates. We used the Cochrane-Armitage test to analyze trends; cohort-matching to evaluate the association of AP and in-hospital mortality, length of stay, and charges; and multivariable logistic regression to test the association of AP and demographics and comorbid conditions.Results
We identified 55,012 cases of AP in hospitalized children (1–20 years of age). The incidence of AP increased from 23.1 to 34.9 (cases per 10,000 hospitalizations per year; P<0.001) and for all-diagnoses 38.7 to 61.1 (P<0.001). There was an increasing trend in the incidence of both primary and all-diagnoses of AP (P<0.001). In-hospital mortality decreased (13.1 to 7.6 per 1,000 cases, P<0.001), median length of stay decreased (5 to 4 days, P<0.001), and median charges increased ($14,956 to $22,663, P<0.001). Children with AP compared to those without the disease had lower in-hospital mortality (adjusted odds ratio, aOR 0.86, 95% CI, 0.78–0.95), longer lengths of stay (aOR 2.42, 95% CI, 2.40–2.46), and higher charges (aOR 1.62, 95% CI, 1.59–1.65). AP was more likely to occur in children older than 5 years of age (aORs 2.81 to 5.25 for each 5-year age interval). Hepatobiliary disease was the comorbid condition with the greatest association with AP.Conclusions
These results demonstrate a rising incidence of AP in hospitalized children. Despite improvements in mortality and length of stay, hospitalized children with AP have significant morbidity. 相似文献59.
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Mojtaba Alimolaei Mehdi Golchin Jalil Abshenas Majid Ezatkhah Mehrdad Shamsaddini Bafti 《Probiotics and antimicrobial proteins》2018,10(2):251-257
The alpha-toxin is one of the virulence factors of Clostridium perfringens for gas gangrene in humans and animals or necrotic enteritis in poultry. The C-terminal domain of this toxin ( cpa 247-370 ) was synthesized and cloned into pT1NX vector to construct the pT1NX-alpha plasmid. This surface-expressing plasmid was electroporated into Lactobacillus casei ATCC 393, generating the recombinant L. casei strain expressing alpha-toxoid (LC-α strain). Expression of this modified alpha-toxoid was confirmed by SDS-PAGE, immunoblotting, and direct immunofluorescence microscopy. BALB/c mice, immunized orally by the recombinant LC-α strain, elicited mucosal and significantly humoral immune responses (p < 0.05) and developed a protection against 900 MLD/mL of the standard alpha-toxin. This study showed that this recombinant LC-α strain could be a promising vaccine candidate against gas gangrene and necrotic enteritis. 相似文献