119 research outputs found

    Metarhizium brunneum Blastospore Pathogenesis in Aedes aegypti Larvae: Attack on Several Fronts Accelerates Mortality

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    Aedes aegypti is the vector of a wide range of diseases (e.g. yellow fever, dengue, Chikungunya and Zika) which impact on over half the world's population. Entomopathogenic fungi such as Metarhizium anisopliae and Beauveria bassiana have been found to be highly efficacious in killing mosquito larvae but only now are the underlying mechanisms for pathogenesis being elucidated. Recently it was shown that conidia of M. anisopliae caused stress induced mortality in Ae. aegypti larvae, a different mode of pathogenicity to that normally seen in terrestrial hosts. Blastospores constitute a different form of inoculum produced by this fungus when cultured in liquid media and although blastospores are generally considered to be more virulent than conidia no evidence has been presented to explain why. In our study, using a range of biochemical, molecular and microscopy methods, the infection process of Metarhizium brunneum (formerly M. anisopliae) ARSEF 4556 blastospores was investigated. It appears that the blastospores, unlike conidia, readily adhere to and penetrate mosquito larval cuticle. The blastospores are readily ingested by the larvae but unlike the conidia are able infect the insect through the gut and rapidly invade the haemocoel. The fact that pathogenicity related genes were upregulated in blastospores exposed to larvae prior to invasion, suggests the fungus was detecting host derived cues. Similarly, immune and defence genes were upregulated in the host prior to infection suggesting mosquitoes were also able to detect pathogen-derived cues. The hydrophilic blastospores produce copious mucilage, which probably facilitates adhesion to the host but do not appear to depend on production of Pr1, a cuticle degrading subtilisin protease, for penetration since protease inhibitors did not significantly alter blastospore virulence. The fact the blastospores have multiple routes of entry (cuticle and gut) may explain why this form of the inoculum killed Ae. aegypti larvae in a relatively short time (12-24hrs), significantly quicker than when larvae were exposed to conidia. This study shows that selecting the appropriate form of inoculum is important for efficacious control of disease vectors such as Ae. aegypti

    Histopathological and apoptotic changes on marine mussels Mytilus galloprovincialis (Lamark, 1819) following exposure to environmental pollutants

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    Marine bivalve mussels, especially Mytilus species are an earlywarning system used for determining of damage caused by the various aquatic pollutions. In the present study, Mytilus galloprovincialis L. (black mussel) have been utilised as a biomonitoring organism to reveal environmental pollution in the Aliaga, Foca and Urla where located along the Izmir Coast of Turkey. Mussels were collected at these areas and gill and hepatopancreas (digestive gland) tissues were excised. mRNA expressions of initiator (caspase-2 and -8) and executioner (caspase -3/7-1, -3/7-2, -3/7-3 and -3/7-4) caspases of mussels tissues in areas exposed to pollution agent have been observed. TUNEL immunoreactivity in paralel to histopathological changes in both Aliaga and Foca areas were compared with Urla. This study is the first report to reveal the pollution with apoptotic expression on mussels in the coast of Turkey. (C) 2016 Elsevier Ltd. All rights reserved

    HISTOLOGICAL EFFECTS OF POLLUTION ON GILL AND HEPATOPANCREAS TISSUES OF BLACK MUSSELS (M. GALLOPROVINCIALIS L.) FROM IZMIR BAY OF TURKEY

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    In the present study, the histological examination of the hepatopancreas (digestive gland) and gills of black mussels, Mytilus galloprovincialis was performed as a part of the biomonitoring programs carried out to assess the biological effects of the Izmir Bay (Western coast of Turkey). Mussels collected from five stations; Urla in the outer Bay and Inciralti, Goztepe, Konak, Pasaport in the inner Bay of Izmir Bay. While normal histology on hepatopancreas tissue was observed in Urla samples, vacuolar degenerations and hemocytic infiltrations were abundant in hepatopancreas throughout the other four stations. Also breakdown of digestive epithelium was determined in only Pasaport station. In gill tissues, while hemocytic infiltration was observed in Urla samples, gradually increasing cilia erosion, fusion, cell loss and necrosis was observed in Inciralti, Goztepe, Konak, Pasaport samples. Lumen was determined as normal in Urla and Goztepe samples and enlarged in Inciralti samples. The lumen in each filament was thinner and in some parts adjoined to each other and in Konak and Pasaport samples. Also the gills abfrontal tissue integrity was disturbed in these two stations

    Angiogenic effect and wound healing potential of Enteromorpha linza L. (Linnaeus) J. Agardh (Green algae) methanol extract

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    41st FEBS Congress on Molecular and Systems Biology for a Better Life -- SEP 03-08, 2016 -- Kusadasi, TURKEYWOS: 000383616900185FEB

    Fluvastatin attenuates doxorubicin-induced testicular toxicity in rats by reducing oxidative stress and regulating the blood–testis barrier via mTOR signaling pathway

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    ###EgeUn###Doxorubicin (DOX) is an anthracycline derivative antibiotic that still frequently used in the treatment of solid tumors and hematological malignancies. The clinical use of DOX is largely restricted due to acute and chronic renal, cardiac, hematological, and testicular toxicities. Previous studies have indicated that oxidative stress, lipid peroxidation, and apoptosis in germ cells are the main factors in DOX-induced testicular toxicity, but the entire molecular mechanisms that responsible for DOX-induced testicular damage are not yet fully understood. Fluvastatin is a cholesterol-lowering agent that acts by inhibiting hydroxylmethyl glutaryl coenzyme A, the key enzyme for cholesterol biosynthesis. In addition to its cholesterol-lowering effect, fluvastatin showed an antioxidant effect by cleaning hydroxyl and superoxide radicals and this drug could have a protective effect by acting on the mammalian target of rapamycin (mTOR) signal pathway in testicular damage caused by obesity. This study aimed to investigate the possible protective and therapeutic effects of fluvastatin on the DOX-induced testicular toxicity model by histochemical, immunohistochemical, biochemical, and real-time polymerase chain reaction analyses. The present study indicates that fluvastatin may have a protective and therapeutic effect by removing reactive oxygen species and by regulating the mTOR, connexin 43, and matrix metalloproteinase 9 protein and messenger ribonucleic acid expressions, which play an important role in regulating the blood–testis barrier. On the other hand, the use of fluvastatin as a protective/prophylactic agent was found to be more effective than the use of this drug for treatment. In light of this information, fluvastatin may be a candidate agent that can be used to prevent testicular toxicity observed in men receiving DOX treatment. © The Author(s) 2019
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