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41.
Pyrenophora teres f. teres (Ptt) causes net form net blotch disease of barley, partially by producing necrosis‐inducing proteins. The protein profiles of the culture filtrates of 28 virulent isolates were compared by a combination of 2DE and 1D‐PAGE with 105 spots and 51 bands chosen for analysis by liquid chromatography electrospray ionization tandem mass spectrometry. A total of 259 individual proteins were identified with 63 of these proteins being common to the selected virulent isolates. Ptt secretes a broad spectrum of proteins including cell wall degrading enzymes; virulence factors and effectors; proteins associated with fungal pathogenesis and development; and proteins related to oxidation–reduction processes. Potential virulence factors and effectors identified included proteins with glucosidase activity, ricin B and concanavalin A‐like lectins, glucanases, spherulin, cutinase, pectin lyase, leucine‐rich repeat protein, and ceratoplatanin. Small proteins with unknown function but cysteine‐rich, common to effectors, were also identified. Differences in the secretion profile of the Ptt isolates have also provided important insight into the different mechanisms contributing to virulence and the development of net form net blotch symptoms. 相似文献
42.
Ismail Lafri Lionel Almeras Idir Bitam Aurelia Caputo Amina Yssouf Claire-Lise Forestier Arezki Izri Didier Raoult Philippe Parola 《PLoS neglected tropical diseases》2016,10(1)
Background
Phlebotomine sand flies are known to transmit Leishmania parasites, bacteria and viruses that affect humans and animals in many countries worldwide. Precise sand fly identification is essential to prevent phlebotomine-borne diseases. Over the past two decades, progress in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has emerged as an accurate tool for arthropod identification. The objective of the present study was to investigate the usefulness of MALDI-TOF MS as a tool for identifying field-caught phlebotomine.Methodology/Principal Findings
Sand flies were captured in four sites in north Algeria. A subset was morphologically and genetically identified. Six species were found in these areas and a total of 28 stored frozen specimens were used for the creation of the reference spectrum database. The relevance of this original method for sand fly identification was validated by two successive blind tests including the morphological identification of 80 new specimens which were stored at -80°C, and 292 unknown specimens, including engorged specimens, which were preserved under different conditions. Intra-species reproducibility and inter-species specificity of the protein profiles were obtained, allowing us to distinguish specimens at the gender level. Querying of the sand fly database using the MS spectra from the blind test groups revealed concordant results between morphological and MALDI-TOF MS identification. However, MS identification results were less efficient for specimens which were engorged or stored in alcohol. Identification of 362 phlebotomine sand flies, captured at four Algerian sites, by MALDI-TOF MS, revealed that the subgenus Larroussius was predominant at all the study sites, except for in M’sila where P. (Phlebotomus) papatasi was the only sand fly species detected.Conclusion
The present study highlights the application of MALDI-TOF MS for monitoring sand fly fauna captured in the field. The low cost, reliability and rapidity of MALDI-TOF MS analyses opens up new ways in the management of phlebotomine sand fly-borne diseases. 相似文献43.
In this article, a new approach—namely, the extended Parker–Sochacki method (EPSM)—is presented for solving the Michaelis–Menten nonlinear enzymatic reaction model. The Parker–Sochacki method (PSM) is combined with a new resummation method called the Sumudu–Padé resummation method to obtain approximate analytical solutions for the model. The obtained solutions by the proposed approach are compared with the solutions of PSM and the Runge–Kutta numerical method (RKM). The comparison proves the practicality, efficiency, and correctness of the presented approach. It serves as a basis for solving other nonlinear biochemical reaction models in the future. 相似文献
44.
45.
Muhammad Khairul Izzuddin Sharaai Amir Hamzah Ismail Mohd Mansor Harun Rosta Yien Wong Siew 《The International Journal of Life Cycle Assessment》2019,24(5):935-944
The International Journal of Life Cycle Assessment - Palm oil is considered as the primary source of income for many farmers in Southeast Asia and become a very important agricultural commodity for... 相似文献
46.
Soltani Mehdi Badzohreh Gholamreza Mirzargar Saed Farhangi Mehrdad Shekarabi Pezhman Hosseini Lymbery Alan 《Probiotics and antimicrobial proteins》2019,11(3):765-773
Probiotics and Antimicrobial Proteins - Growth behavior and production of short-chain fatty acid (SCFA) of two probiotics, Pediococcus acidilactici and Lactococcus lactis, each at... 相似文献
47.
Okon EB Chung AW Zhang H Laher I van Breemen C 《Canadian journal of physiology and pharmacology》2007,85(5):562-567
Diabetes mellitus impairs endothelial function, which can be considered as the hallmark in the development of cardiovascular diseases. Hyperglycemia, hyperinsulinemia, and hyperlipidemia are believed to contribute to endothelial dysfunction. In the present study, we investigated the possible links among these plasma metabolic markers and endothelial function in a mouse model during the development of type 2 diabetes. C57BL/6J-Lepob/ob mice at 8, 12, and 16 weeks were used to study endothelial function during the establishment of type 2 diabetes. Endothelial function was accessed in vitro in the thoracic aorta by measuring acetylcholine (ACh)-stimulated vasodilatation. Blood plasma was obtained for the measurements of glucose, insulin, triglycerides, and cholesterol levels. Correlation and multiple regression analysis revealed strong negative associations between the ACh responsiveness and the plasma levels of glucose, insulin, and lipid profiles at the age of 8 weeks. Associations were observed at neither older age nor in C57BL/6J mice. In conclusion, the increase in plasma levels of glucose, insulin, and lipids is associated with the impairment of the endothelial function during the early stage of the development of type 2 diabetes. The loss of correlation at an older age suggests multifactorial regulation of endothelial function and cardiovascular complications at later stages of the disease. 相似文献
48.
49.
Anvar Soleimani Amirhossein Bahreyni Mostafa K. Roshan Arash Soltani Mikhail Ryzhikov Mojtaba Shafiee Mohammad Soukhtanloo Mahmoud R. Jaafari Baratali Mashkani Seyed M. Hassanian 《Journal of cellular physiology》2019,234(3):2329-2336
The hypoxic niche of tumor leads to a tremendous increase in the extracellular adenosine concentration through alteration of adenosine metabolism in the tumor microenvironment (TME). This consequently affects cancer progression, local immune responses, and apoptosis of tumor cells. Regulatory effect of adenosine on apoptosis in TME depends on the cancer cell type, pharmacological characteristics of adenosine receptor subtypes, and the adenosine concentration in the tumor niche. Exploiting specific pharmacological adenosine receptor agonist and antagonist inducing apoptosis in cancer cells can be considered as a proper procedure to control cancer progression. This review summarizes the regulatory role of adenosine in cancer cell apoptosis for a better understanding, and hence better management of the disease. 相似文献
50.
Arash Soltani Kolsoum Rezaie Kahkhaie Saeed Mohammadian Haftcheshmeh Ahmad Ali Jalali Nezhad Masoud Mashhadi Akbar Boojar 《Journal of cellular biochemistry》2019,120(5):7573-7580
Nowadays, increased use of nanomaterials in industry and biomedicine poses potential risks to human health and the environment. Studying their possible toxicological effects is therefore of great significance. The present investigation was designed to examine the status of oxidative stress induced by nanoparticles (NPs) of ferric oxide (Fe2O 3) and titanium oxide (TiO 2) with their micro-sized counterpart on mouse lung and bone marrow–derived normal tissue cells. We assessed the induction of oxidative stress by measuring its indicators such as antioxidant scavenging activity of superoxide dismutase and catalase as well as malondialdehyde concentration. Moreover, colony formation of bone marrow cells was assayed following induction with colony stimulating factor (CSF) from lung cells. NPs had a more potent stimulatory effect on the oxidative stress status than their micron-sized counterparts. In addition, the highest level of oxidative stress derived from TiO 2 NPs was observed in both tissue types. Cotreatment with NPs and the antioxidant α-tocopherol reduced antioxidant activities and membrane lipid peroxidation (LPO) in the lung cells, but increased CSF-induced colony formation activity of bone marrow cells, suggesting that oxidative stress may be the cause of the cytotoxic effects of NPs. It is concluded that free radicals generated following exposure to NPs resulted in significant oxidative stress in mouse cells, indicated by increased LPO and antioxidant enzyme activity and decreased colony formation. 相似文献