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Maryam Ghodrati Siahmazgi Mohammad Ali Nasiri Khalili Mehdi Zeinoddini Fathollah Ahmadpour Sirus Khodadadi 《International journal of peptide research and therapeutics》2020,26(2):767-774
Immunotoxin is a recombinant fusion toxin which has been developed to kill cancer cells selectively. DT389GCSF as a new immunotoxin consists of a truncated 相似文献
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Kohan SA Gundersen CB 《Journal of experimental zoology. Part A, Comparative experimental biology》2003,300(2):113-125
Calcium (Ca) ionophores trigger cortical granule exocytosis in progesterone-matured Xenopus oocytes (eggs), but not in immature oocytes. Prior work suggested that this secretory transition involved a Ca-dependent isoform of protein kinase C (PKC). To address this possibility, we treated eggs with several different inhibitors of Ca-dependent PKCs. Although these agents (eg., staurosporine, Ro31-8220) completely blocked cortical granule exocytosis that is triggered in eggs by phorbol esters, they had no impact on ionomycin-evoked secretion of cortical granule lectin. These data suggest that Ca-dependent PKCs do not mediate secretory triggering in eggs. Instead, further investigation revealed that protein synthesis (but not RNA synthesis) was required for eggs to secrete in response to ionomycin. Moreover, we observed that when oocytes were matured by injection of maturation promoting factor (MPF), they failed to secrete in response to ionomycin. Collectively, these results suggest that the progesterone-dependent maturation pathway induces these cells either to synthesize de novo, a protein that mediates Ca-dependent secretory triggering, or that intrinsic Ca-sensing machinery is modified in a protein-synthesis-dependent fashion. Initial efforts to distinguish between these possibilities (using Ca overlay, pharmacological and immunoblot strategies) revealed that such Ca-binding proteins as calmodulin, synaptotagmin1, CAPS, rabphilin-3A and calcineurin were unlikely to transduce the secretory effects of ionomycin in eggs. Thus, the cortical reaction in these cells may rely on a novel mechanism for initiating Ca-dependent exocytosis. 相似文献
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Rajendra K. Gangalum Joseph Horwitz Sirus A. Kohan Suraj P. Bhat 《The Journal of biological chemistry》2012,287(50):42407-42416
αA-Crystallin (αA) and αB-crystallin (αB), the two prominent members of the small heat shock family of proteins are considered to be two subunits of one multimeric protein, α-crystallin, within the ocular lens. Outside of the ocular lens, however, αA and αB are known to be two independent proteins, with mutually exclusive expression in many tissues. This dichotomous view is buoyed by the high expression of αA and αB in the lens and their co-fractionation from lens extracts as one multimeric entity, α-crystallin. To understand the biological function(s) of each of these two proteins, it is important to investigate the biological basis of this perceived dichotomy; in this report, we address the question whether αA and αB exist as independent proteins in the ocular lens. Discontinuous sucrose density gradient fractionation and immunoconfocal localization reveal that in early developing rat lens αA is a membrane-associated small heat shock protein similar to αB but with remarkable differences. Employing an established protocol, we demonstrate that αB predominantly sediments with rough endoplasmic reticulum, whereas αA fractionates with smooth membranes. These biochemical observations were corroborated with immunogold labeling and transmission electron microscopy. Importantly, in the rat heart also, which does not contain αA, αB fractionates with rough endoplasmic reticulum, suggesting that αA has no influence on the distribution of αB. These data demonstrate presence of αA and αB in two separate subcellular membrane compartments, pointing to their independent existence in the developing ocular lens. 相似文献
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Samira Shahnazariaval Jaber Karimi Sirus Aghajanzade Gholamhosein Hasanshahi Azizi sheikhi Gojan 《Archives Of Phytopathology And Plant Protection》2013,46(17):2062-2069
The citrus cottony scale, Pulvinaria aurantii Cock. (Hem.: Coccidae) is one of the most important citrus pests in Iran. This study investigated the toxicity and synergistic effects of organophosphorous insecticides (Malathion, Chlorpyrifos, Buprofezin and DG oil) on first nymphal instars of P. aurantii in the laboratory conditions (25?±?1?°C, 75?±?5% RH and 16L:8D photoperiod). The values of LC50 for Malathion, Chlorpyrifos and Buprofezin insecticides on the first nymphal instars were calculated as 76.90, 105.25 and 24.70?ppm, respectively. Also, results indicated that Buprofezin and Pyriproxifen are the most effective insecticides on first nymphal instars of P. aurantii. The values of LC50 for each insecticide without oil and in half dose along with DG oil were equal. This was an indication for synergism role of DG oil combination. The results of this study showed that DG oil not only decreases the consumption of insecticides, but also increases their efficacy. 相似文献
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Oveis Karima Gholamhossein Riazi Sirus Khodadadi Hassan Aryapour Mohammad Ali Nasiri Khalili Leila Yousefi Ali Akbar Moosavi-Movahedi 《FEBS letters》2012,586(21):3914-3919
Tau isoforms promote neuronal integrity through binding and stabilization of microtubule proteins (MTP). It has been shown that hyperphosphorylation of tau contributes to Alzheimer’s disease (AD) pathology and related tauopathies. However, other pathogenic modifications of tau have not been well characterized. It is well accepted that elevated level of homocysteine (Hcy) is associated with neurodegenerative diseases such as AD. As a result of N-homocysteinylation of lysine residues, Hcy becomes a component of proteins, as a protein–homocystamide adduct, which affects protein structure and function. Here we demonstrate that N-homocysteinylation of human tau (4R/1N isoform) inhibits its function via impaired tau–tubulin specific binding and MTP assembly dynamics in vitro. 相似文献
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Hatam Boustani Sirus Pakseresht Mohammad-Reza Haghdoust Saeid Qanbari Hadis Mehregan-Nasab 《生物学前沿》2017,12(3):235-239
Background
Gastrointestinal disorders are common complaints for which endoscopy and colonoscopy are the most important diagnostic procedures. Anxiety is an unpleasant, ambiguous feeling of apprehension and fear of unknown origin that occurs during stressful situations or injury. Lack of sufficient information and fear of pain can cause anxiety prior to a colonoscopy, reducing the number of patients willing to undergo the procedure and increasing colonoscopy time. The aim of this study was to evaluate the efficacy of psychological preparation on anxiety before colonoscopy in patients presenting to Golestan Hospital during the years 1994 and 1995.Material and Methods
This study was a double-blind clinical trial of patients presenting to the colonoscopy unit in Golestan Hospital in 1994 and 1995. A total of 80 patients were divided into two groups: intervention and control. A primary assessment of anxiety was performed using Spielberger’s State-Trait Anxiety Inventory. Before the colonoscopy, the State-Trait Anxiety Inventory was completed by the patients again. The effectiveness of psychological preparation before colonoscopy and its effect on anxiety were evaluated using statistical software SPSS 20.Results
The mean age of participants was 46.33±12.2 years in the intervention group and 44.8±12.26 years in the control group. In this study, there were 41 males (51.3%) and 39 females (48.7%); 15 patients (18.7%) were single and the rest married. In terms of demographic variables, there were no significant differences between the two groups (p>0.05). The average scores of state and trait anxiety in the intervention group showed a statistically significant difference before and after the intervention (p = 0.000).Conclusion
Trait and state anxiety levels after psychological preparation showed a statistically significant reduction. This indicates the effectiveness of intervention programs to reduce anxiety before colonoscopy.8.
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Abstract Hyperhomocysteinemia has recently been identified as an important risk factor for Alzheimer's disease (AD). One of the potential mechanisms underlying harmful effects of homocysteine (Hcy) is site-specific acylation of proteins at lysine residues by homocysteine thiolactone (HCTL). The accumulation of amyloid β-peptide (Aβ) in the brain is a neuropathological hallmark of AD. In the present study we were interested to investigate the effects of N-homocysteinylation on the aggregation propensity and neurotoxicity of Aβ(1-42). By coupling several techniques, we demonstrated that the homocysteinylation of lysine residues increase the neurotoxicity of the Aβ peptide by stabilizing soluble oligomeric intermediates. 相似文献
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