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1.
Islet transplantation has become a promising treatment in the therapy of type 1 diabetes. Its function improvement, after isolation and before transplantation, is crucial because of their loss both in number and function of islets after isolation procedures. Trace elements sodium orthovanadate (SOV) and sodium molybdate (SM), as well as medicinal plant Teucrium polium L. (TP), showed and possessed high beneficial antioxidative potential and even hypoglycemic properties via their effect on islets. We evaluated the effect of these components in combination on cultured islet function in order to improve pancreatic islet transplantation. Rat pancreatic islets were cultured for 24 h then incubated with different concentrations of TP (0.01 and 0.1 mg/mL) alone and in combination with SOV (1 mM) or SM (1 mM). Insulin concentration in buffer media was measured as islet secretory function. Administration of TP (0.01 mg/mL), SM, and SOV alone or in combination with each other significantly increased insulin secretion at high glucose concentration (16.7 mM); insulin secretion was significantly greater in the group containing both TP and SM than other treated groups (p < 0.05). The combination of the mentioned trace elements especially molybdate with TP could improve islet cells function before transplantation.  相似文献   
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Phyllody is a destructive disease of sesame (Sesamum indicum L.) in Iran. The major symptoms of the disease are floral virescence, phyllody and proliferation. Other symptoms which sometimes accompany the disease are yellowing, cracking of seed capsules, germination of seeds in the capsules and formation of dark exudates on the foliage. Light microscopy of hand-cut sections of sesame and colza (Brassica napus L. cv. Oro) stems treated with Dienes' stain showed blue areas in the phloem region of phyllody infected plants. Mycoplasma-like bodies were found in the sieve cells of infected sesame stems when thin sections were examined m an electron microscope. Sesame phyllody was successfully transmitted from sesame to sesame by grafting. Among various leafhoppers collected in sesame fields only Neoaliturus haematoceps transmitted the disease. This is the first report on the identification of a Mycoplasma-like organism (MLO) as the cause of sesame phyllody and N. haematoceps as an MLO vector in Iran. In host range studies using the leafhopper vector, only B. napus cv. Oro, Lepidium sativum, Catharanthus roseus, Lactuca sp. and Portulaca oleracea, but not 17 other species, developed symptoms. The species of vector and host range of MLO indicate that sesame phyllody in Iran is different from that reported in India and Upper Volta.  相似文献   
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Heavy metals’ origin, accumulation, and distribution in soil have been the focus of much attention by many researchers. The objective of this study was to recognize the sources of heavy metals in surface soils in Hamadan Province in western Iran using multivariate geostatistical techniques. A total of 263 surface (0–10 cm) soil samples and 18 rock samples from major parent materials were collected. Cobalt (Co), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) contents of the samples were determined. Selected soil physical and chemical characteristics were also measured. A multivariate geostatistical analysis was performed to identify the common source of heavy metals. The quantities of Co, Cr, and Ni were found to be associated with parent rocks, corresponding to the first factor termed the “lithologic component.” The second factor was mainly attributed to Cu, which also comprised the first and third factors, indicating a mixed source both from lithologic and anthropogenic inputs. Zn and Pb contents were related to the anthropogenic activities and comprised the third factor. A significant correlation was found between metals from the lithogenic sources and selected soil properties such as soil organic matter, clay, CEC, and carbonate, indicating an interaction among them. Generally, Zn and Pb showed a less significant correlation with soil properties.  相似文献   
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In this study, the diversity of Plasmodium vivax populations circulating in Pakistan and Iran has been investigated by using circumsporozoite protein (csp) and merozoite surface proteins 1 and 3α (msp-1 and msp-3α) genes as genetic markers. Infected P. vivax blood samples were collected from Pakistan (n = 187) and Iran (n = 150) during April to October 2008, and were analyzed using nested-PCR/RFLP and sequencing methods. Genotyping pvmsp-1 (variable block 5) revealed the presence of type 1, type 2 and recombinant type 3 allelic variants, with type 1 predominant, in both study areas. The sequence analysis of 33 P. vivax isolates from Pakistan and 30 from Iran identified 16 distinct alleles each, with one allele (R-8) from Iran which was not reported previously. Genotyping pvcsp gene also showed that VK210 type is predominant in both countries. Moreover, based on the size of amplified fragment of pvmsp-3α, three major types: type A (1800 bp), type B (1500 bp) and type C (1200 bp), were distinguished among the examined isolates that type A was predominant among Pakistani (72.7%) and Iranian (77.3%) parasites. PCR/RFLP products of pvmsp-3α with HhaI and AluI have detected 40 and 39 distinct variants among Pakistani and Iranian examined isolates, respectively. Based on these three studied genes, the rate of combined multiple genotypes were 30% and 24.6% for Pakistani and Iranian P. vivax isolates, respectively. These results indicate an extensive diversity in the P. vivax populations in both studies.  相似文献   
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Molecular Biology Reports - Monoclonal antibodies (mAbs) are widely employed as invaluable therapeutics for a vast number of human disorders. Several approaches have been introduced for the...  相似文献   
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Non-albicans Candida species and other rare yeasts have emerged as major opportunistic pathogens in fungal infections. Identification of opportunistic yeasts in developing countries is mainly performed by phenotypic assay, which are time-consuming and prone to errors. The aim of the present study was to evaluate PCR-RFLP as a routinely used identification technique for the most clinically important Candida species in Iran and make a comparison with a novel multiplex PCR, called 21-plex PCR. One hundred and seventy-three yeast isolates from clinical sources were selected and identified with sequence analysis of the D1/D2 domains of rDNA (LSU rDNA) sequencing as the gold standard method. The results were compared with those obtained by PCR-RFLP using MspI restriction enzyme and the 21-plex PCR. PCR-RFLP correctly identified 93.4% of common pathogenic Candida species (C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, and P. kudriavsevii (=?C. krusei)) and was able to identify 45.5% of isolates of the uncommon yeast species compared to the D1/D2 rDNA sequencing. Compared with PCR-RFLP, all common Candida species and 72.7% of uncommon yeast species were correctly identified by the 21-plex PCR. The application of the 21-plex PCR assay as a non-sequence-based molecular method for the identification of common and rare yeasts can reduce turnaround time and costs for the identification of clinically important yeasts and can be applied in resource-limited settings.

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9.

One of the technology for increasing the safety and welfare of humans in roads is Vehicular Cloud Computing (VCC). This technology can utilize cloud computing advantages in the Vehicular Ad Hoc Network (VANET). VCC by utilizing modern equipment along with current vehicles, can play a significant role in the area of smart transportation systems. Given the potential of this technology, effective methods for managing existing resources and providing the expected service quality that is essential for such an environment are not yet available as it should. One of the most important barriers to providing such solutions seems to be resource constraints and very high dynamics in vehicles in VCC. In this article, based on virtualization and taking into account the environment with these features, we propose simple ways to manage resources better and improve the quality of service. We were able to achieve better results in simulation than previous methods by providing a flexible data structure to control the important data in the environment effectively. To illustrate the impact of the proposed methods, we compared them with some of the most important methods in this context, and we used SUMO 1.2.0 and MATLAB R2019a software to simulate them. Simulation results indicate that the proposed methods provide better results than previous methods in terms of resource efficiency, Quality of Service (QoS), and load balancing.

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10.
Constitutive phosphorylation of protein kinase B (AKT) is a common feature of cancer caused by genetic alteration in the phosphatase and tensin homolog (PTEN) gene and is associated with poor prognosis. This study determined the role of cytosolic phospholipase A2α (cPLA2α) in AKT, extracellular signal-regulated kinase (ERK) and androgen receptor (AR) signaling in PTEN-null/mutated prostate cancer cells. Doxycycline (Dox)-induced expression of cPLA2α led to an increase in pAKT, pGSK3β and cyclin D1 levels in LNCaP cells that possess a PTEN frame-shift mutation. In contrast, silencing cPLA2α expression with siRNA decreased pAKT, pGSK3β and cyclin D1 levels in both PC-3 (PTEN deletion) and LNCaP cells. Silencing of cPLA2α decreased pERK and AR protein levels. The inhibitory effect of cPLA2α siRNA on pAKT and AR protein levels was reduced by the addition of arachidonic acid (AA), whereas the stimulatory effect of AA on pAKT, pERK and AR levels was decreased by an inhibitor of 5-hydroxyeicosatetraenoic acid production. Pharmacological blockade of cPLA2α with Efipladib reduced pAKT and AR levels with a concomitant inhibition of PC-3 and LNCaP cell proliferation. These results demonstrate an important role for cPLA2α in sustaining AKT, ERK and AR signaling in PTEN-null/mutated prostate cancer cells and provide a potential molecular target for treating prostate cancer.  相似文献   
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