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81.
Salehi Jouzani G Seifinejad A Saeedizadeh A Nazarian A Yousefloo M Soheilivand S Mousivand M Jahangiri R Yazdani M Amiri RM Akbari S 《Canadian journal of microbiology》2008,54(10):812-822
The characterization of nematode-effective strains and cry genes in the Iranian Bacillus thuringiensis (Bt) collection (70 isolates) is presented. Characterization was based on PCR analysis using 12 specific primers for cry5, cry6, cry12, cry13, cry14, and cry21 genes encoding proteins active against nematodes, crystal morphology, and protein band patterns as well as their nematicidal activity on root-knot nematode (Meloidogyne incognita) and two free-living nematodes (Chiloplacus tenuis and Acrobeloides enoplus). PCR results with primers for these genes showed that 22 isolates (31.5%) contain a minimum of one nematode-active cry gene. Strains containing the cry6 gene were the most abundant and represent 22.8% of the isolates. Bt strains harboring cry14 genes were also abundant (14.2%). cry21 and cry5 genes were less abundant, found in 4.2% and 2.8% of the strains, respectively. In total, six different nematode-active cry gene profiles were detected in this collection. Four isolates did not show the expected PCR product size for cry5, cry6, and cry21 genes; they might contain potentially novel insecticidal crystal protein genes. Twenty-two Bt isolates containing nematode-active cry genes were selected for preliminary bioassays on M. incognita. Based on these bioassays, four isolates were selected for detailed bioassays. Isolates YD5 and KON4 at 2 x 10(8) CFU/mL concentrations showed 77% and 81% toxicity on M. incognita, respectively. The free-living nematodes C. tenuis and A. enoplus were more susceptible and the highest mortality was observed within 48 h of incubation at all of the concentrations tested. Maximum mortality was recorded for isolates SN1 and KON4 at 2 x 10(8) CFU/mL concentrations and resulted in 68% and 77% adults deaths of C. tenuis and 68% and 72% for A. enoplus, respectively. Our results showed that PCR is a useful technique for toxicity prediction of nematicidal Bt isolates. 相似文献
82.
Kavoosi G Ardestani SK Kariminia A Zeinali M Alimohammadian MH 《Experimental parasitology》2008,120(1):62-66
Protozoan parasites of the genus Leishmania secrete a range of proteophosphoglycans (PPG) known to be important for successful colonization of Leishmania in the sandfly and for virulence in the mammalian host. PPGs are a large family of extensively glycosylated proteins with some unusual and unique features. In this study we purified PPG from culture supernatant of Leishmania major metacyclic promastigotes. In discontinuous SDS-PAGE, PPG could not enter the resolving gel but after mild acid hydrolysis several bands resolved. Agarose gel electrophoresis and immunoblot analysis using monoclonal antibody (WIC 79.3) indicated that the PPG preparation consisted of heterogeneous molecules. Compositional analysis showed that the PPG preparation contained 67% glycan, 28% protein and 5% phosphate. Additionally, the effect of PPG on reactive oxygen species (ROS) production and induction of IL-10, IL-12 and IFN-γ secretion by human peripheral blood mononuclear cells (PBMCs) isolated from healthy individuals was investigated. The water-soluble secreted form of PPG at a concentration of 1 μg glycan/ml seems to be a potent inducer of ROS and IL-10 and to a lesser extent of IFN-γ and IL-12. Cytokines and ROS production was decreased in a dose-dependent manner as the concentration of PPG was increased to 100 μg glycan/ml. 相似文献
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84.
Samaneh Shojaei Seyed Mahmoud Hashemi Hossein Ghanbarian Mohammad Salehi Samira Mohammadi-Yeganeh 《Journal of cellular physiology》2019,234(4):3394-3409
Mesenchymal stem cells (MSCs) are multipotent cells with the potential to differentiate into different cell types. Owing to their immunosuppressive and anti-inflammatory properties, they are widely used in regenerative medicine, but they have a dual effect on cancer progression and exert both growth-stimulatory or -inhibitory effects on different cancer types. It has been proposed that these controversial effects of MSC in tumor microenvironment (TME) are mediated by their polarization to proinflammatory or anti-inflammatory phenotype. In addition, they can polarize the immune system cells that in turn influence tumor progression. One of the mechanisms involved in the TME communications is extracellular vesicles (EVs). MSCs, as one of cell populations in TME, produce a large amount of EVs that can influence tumor development. Similar to MSC, MSC-EVs can exert both anti- or protumorigenic effects. In the current study, we will investigate the current knowledge related to MSC role in cancer progression with a focus on the MSC-EV content in limiting tumor growth, angiogenesis, and metastasis. We suppose MSC-EVs can be used as safe vehicles for delivering antitumor agents to TME. 相似文献
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88.
Karimeh Haghani Pouyan Asadi Gholamreza Taheripak Ali Noori-Zadeh Shahram Darabi Salar Bakhtiyari 《生物学前沿》2018,13(6):406-417
Background
Diabetes mellitus (DM) is one of the most prevalent chronic diseases, and its prevalence continues to increase globally. The impact of mitochondrial dysfunction and lipid metabolism on diabetes mellitus and insulin resistance (IR) has been implicated in several previous reports; however, the results of studies are confusing despite four decades of study.Methods/Results
This review has evaluated updated understanding of the role of mitochondrial dysfunction and lipid metabolism on type 2 diabetes, and found that mitochondrial dysfunction and lipid metabolism disorder induce the dysregulation of liver and pancreatic beta cells, insulin resistance, and type 2 diabetes.Conclusion
Mitochondrial dysfunction and lipid metabolism induce metabolic dysregulation and finally increasing the possibility of diabetes.89.
Bijan Keikhaei Pejman Slehi-fard Gholamreza Shariati Abbas Khosravi 《Biochemical genetics》2018,56(5):506-521
Alpha thalassemia is the most prevalent monogenic gene disorder in the world, especially in Mediterranean countries. In the current hematological phenotype of patients with different genotypes, the effects of missense mutations on the protein function and also stability were evaluated in a large cohort study. A total of 1,560 subjects were enrolled in the study and divided into two groups: 259 normal subjects; and 1301 alpha-thalassemia carriers. Genomic DNA was extracted and analyzed using ARMS PCR, Multiplex Gap, and direct sequencing. The effects of single nucleotide change on the protein function and stability were predicted by freely available databases of human polymorphisms. Sixty-three different genotypes were seen in the patients. The more prevalent was heterozygote form of ?α3.7 (41.4%) followed by ?α3.7 homozygote (11.6%) and ?MED (3.8%). The significant differences were seen in mean hemoglobin level [F?=?20.5, p?<?0.001] between the Alpha-globin genotypes, when adjusted for gender. Moreover, 28 different mutations were found in our study. A significant relationship was seen between ethnicity and the alpha-globin mutation frequency χ2 (df;8)?=?38.36, p?<?0.0001). Different genotypes could display as different phenotypes. The mutation frequency distributions in our region are different from those of other parts of Iran. Significant differences are seen in the spectrum of mutation frequency among various ethnicities. Finally, some missense mutations might not have considerable effect on the proteins, and they could be neutral mutations. 相似文献