191 research outputs found

    IDENTIFIKASI PARASIT PADA BIAWAK AIR (VARANUS SALVATOR) DI BANDA ACEH

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    IDENTIFIKASI PARASIT PADA BIAWAK AIR (Varanus salvator) DI BANDA ACEHABSTRAKPenelitian ini bertujuan mengidentifikasi jenis parasit serta menentukan tingkat prevalensi jenis-jenis parasit pada biawak air (Varanus salvator) yang ditangkap di Banda Aceh. Biawak yang digunakan sebanyak 50 ekor dan diperiksa di Laboratorium Parasitologi Fakultas Kedokteran Hewan Universitas Syiah Kuala. Pemeriksaan ektoparasit pada permukaan tubuh dilakukan dengan cara langsung. Pemeriksaan endoparasit dilakukan dengan cara pengamatan pada darah dengan menggunakan metode darah apus dan teknik sentrifugasi mikrohematokrit (mHCT), sedangkan pemeriksaan feses menggunakan metode apung, sedimentasi Borray dan pembedahan saluran pencernaan dilakukan apabila didapatkan minimal 3 jenis telur cacing (1 cestoda, 1 nematoda, dan 1 trematoda). Identifikasi parasit dilakukan secara mikroskopis. Hasil pengamatan pada darah tidak ditemukan parasit. Pengamatan pada kulit didapatkan ektoparasit Amblyomma sp dengan tingkat prevalensi 100% kategori selalu. Pengamatan pada feses ditemukan Ascaris sp dengan tingkat prevalensi 74% kategori biasa dan Stronyloides spp. dengan tingkat prevalensi 8% kategori kadang-kadang. Berdasarkan hasil penelitian, dapat disimpulkan bahwa ada beberapa jenis parasit yang dapat menginfestasi biawak air (Varanus salvator) antara lain Amblyomma sp, Ascaris sp, dan Strongyloides spp. dengan tingkat prevalensi berbeda-beda

    A common framework of NBTI generation and recovery in plasma-nitrided SiON p-MOSFETs

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    Generation and recovery of degradation during and after negative bias temperature instability (NBTI) stress are studied in a wide variety of plasma-nitrided (PN) silicon oxynitride (SiON) p-MOSFETs. An ultrafast on-the-fly linear drain current (IDLIN) technique, which is capable of measuring the shift in threshold voltage from very short (approximately in microseconds) to long (approximately in hours) stress/ recovery time, is used. The mechanics of NBTI generation and recovery are shown to be strongly correlated and can be consistently explained using the framework of an uncorrelated sum of a fast and weakly temperature (T)-dependent trapped-hole (Vh) component and a relatively slow and strongly T-activated interface trap (VIT) component. The SiON process dependences are attributed to the difference in the relative contributions of Vh and VIT to the overall degradation (VT), as dictated by the nitrogen (N) content and thickness of the gate insulator

    Polysaccharides Cellulose, Poly-Β -1,6-N-Acetyl-D-Glucosamine, and Colanic Acid Are Required for Optimal Binding of Escherichia coli O157:H7 Strains to Alfalfa Sprouts and K-12 Strains to Plastic but Not for Binding to Epithelial Cells

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    When Escherichia coli O157:H7 bacteria are added to alfalfa sprouts growing in water, the bacteria bind tightly to the sprouts. In contrast, laboratory K-12 strains of E. coli do not bind to sprouts under similar conditions. The roles of E. coli O157:H7 lipopolysaccharide (LPS), capsular polysaccharide, and exopolysaccharides in binding to sprouts were examined. An LPS mutant had no effect on the binding of the pathogenic strain. Cellulose synthase mutants showed a significant reduction in binding; colanic acid mutants were more severely reduced, and binding by poly-Ξ²-1,6-N-acetylglucosamine (PGA) mutants was barely detectable. The addition of a plasmid carrying a cellulose synthase gene to K-12 strains allowed them to bind to sprouts. A plasmid carrying the Bps biosynthesis genes had only a marginal effect on the binding of K-12 bacteria. However, the introduction of the same plasmid allowed Sinorhizobium meliloti and a nonbinding mutant of Agrobacterium tumefaciens to bind to tomato root segments. These results suggest that although multiple redundant protein adhesins are involved in the binding of E. coli O157:H7 to sprouts, the polysaccharides required for binding are not redundant and each polysaccharide may play a distinct role. PGA, colanic acid, and cellulose were also required for biofilm formation by a K-12 strain on plastic, but not for the binding of E. coli O157:H7 to mammalian cells

    Highlights of the 11th International Bordetella Symposium: from Basic Biology to Vaccine Development

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    ABSTRACT Pertussis is a severe respiratory disease caused by infection with the bacterial pathogen Bordetella pertussis . The disease affects individuals of all ages but is particularly severe and sometimes fatal in unvaccinated young infants. Other Bordetella species cause diseases in humans, animals, and birds. Scientific, clinical, public health, vaccine company, and regulatory agency experts on these pathogens and diseases gathered in Buenos Aires, Argentina from 5 to 8 April 2016 for the 11th International Bordetella Symposium to discuss recent advances in our understanding of the biology of these organisms, the diseases they cause, and the development of new vaccines and other strategies to prevent these diseases. Highlights of the meeting included pertussis epidemiology in developing nations, genomic analysis of Bordetella biology and evolution, regulation of virulence factor expression, new model systems to study Bordetella biology and disease, effects of different vaccines on immune responses, maternal immunization as a strategy to prevent newborn disease, and novel vaccine development for pertussis. In addition, the group approved the formation of an International Bordetella Society to promote research and information exchange on bordetellae and to organize future meetings. A new Bordetella.org website will also be developed to facilitate these goals

    Highlights of the 11th International Bordetella Symposium: From basic biology to vaccine development

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    Pertussis is a severe respiratory disease caused by infection with the bacterial pathogen Bordetella pertussis. The disease affects individuals of all ages but is particularly severe and sometimes fatal in unvaccinated young infants. Other Bordetella species cause diseases in humans, animals, and birds. Scientific, clinical, public health, vaccine company, and regulatory agency experts on these pathogens and diseases gathered in Buenos Aires, Argentina from 5 to 8 April 2016 for the 11th International Bordetella Symposium to discuss recent advances in our understanding of the biology of these organisms, the diseases they cause, and the development of new vaccines and other strategies to prevent these diseases. Highlights of the meeting included pertussis epidemiology in developing nations, genomic analysis of Bordetella biology and evolution, regulation of virulence factor expression, new model systems to study Bordetella biology and disease, effects of different vaccines on immune responses, maternal immunization as a strategy to prevent newborn disease, and novel vaccine development for pertussis. In addition, the group approved the formation of an International Bordetella Society to promote research and information exchange on bordetellae and to organize future meetings. A new Bordetella.org website will also be developed to facilitate these goals.Instituto de Biotecnologia y Biologia Molecula

    Highlights of the 11th International Bordetella Symposium: From basic biology to vaccine development

    Get PDF
    Pertussis is a severe respiratory disease caused by infection with the bacterial pathogen Bordetella pertussis. The disease affects individuals of all ages but is particularly severe and sometimes fatal in unvaccinated young infants. Other Bordetella species cause diseases in humans, animals, and birds. Scientific, clinical, public health, vaccine company, and regulatory agency experts on these pathogens and diseases gathered in Buenos Aires, Argentina from 5 to 8 April 2016 for the 11th International Bordetella Symposium to discuss recent advances in our understanding of the biology of these organisms, the diseases they cause, and the development of new vaccines and other strategies to prevent these diseases. Highlights of the meeting included pertussis epidemiology in developing nations, genomic analysis of Bordetella biology and evolution, regulation of virulence factor expression, new model systems to study Bordetella biology and disease, effects of different vaccines on immune responses, maternal immunization as a strategy to prevent newborn disease, and novel vaccine development for pertussis. In addition, the group approved the formation of an International Bordetella Society to promote research and information exchange on bordetellae and to organize future meetings. A new Bordetella.org website will also be developed to facilitate these goals.Instituto de Biotecnologia y Biologia Molecula

    Genotoxic agents promote the nuclear accumulation of annexin A2: role of annexin A2 in mitigating DNA damage

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    Annexin A2 is an abundant cellular protein that is mainly localized in the cytoplasm and plasma membrane, however a small population has been found in the nucleus, suggesting a nuclear function for the protein. Annexin A2 possesses a nuclear export sequence (NES) and inhibition of the NES is sufficient to cause nuclear accumulation. Here we show that annexin A2 accumulates in the nucleus in response to genotoxic agents including gamma-radiation, UV radiation, etoposide and chromium VI and that this event is mediated by the nuclear export sequence of annexin A2. Nuclear accumulation of annexin A2 is blocked by the antioxidant agent N-acetyl cysteine (NAC) and stimulated by hydrogen peroxide (H2O2), suggesting that this is a reactive oxygen species dependent event. In response to genotoxic agents, cells depleted of annexin A2 show enhanced phospho-histone H2AX and p53 levels, increased numbers of p53-binding protein 1 nuclear foci and increased levels of nuclear 8-oxo-2'-deoxyguanine, suggesting that annexin A2 plays a role in protecting DNA from damage. This is the first report showing the nuclear translocation of annexin A2 in response to genotoxic agents and its role in mitigating DNA damage.Natural Sciences and Engineering Research Council of Canada (NSERC); European Union [PCOFUND-GA-2009-246542]; Foundation for Science and Technology of Portugal; Beatrice Hunter Cancer Research Institute; Terry Fox Foundationinfo:eu-repo/semantics/publishedVersio

    Use of wild Pennisetum species for improving biotic and abiotic stress tolerance in pearl millet

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    Pearl millet [Pennisetum glaucum (L.) R. Br.] is one of the world’s hardiest warmseason cereal crop cultivated for food and animal feed in the semi-arid tropics of Asia and Africa. This crop faces terminal drought during rainy and flowering-stage heat stress during summer seasons. Blast is emerging as a serious threat affecting its production and productivity in India. Using wild P. violaceum (Lam) Rich. and pearl millet cultivars, prebreeding populations were developed following backcross method. These populations were evaluated in target ecologies in India at three locations during the 2018 summer season for flowering-stage heat stress and at two locations during the 2018 rainy season for terminal drought stress.Atotal 18 introgression lines (ILs) from Population (Pop) 3 exhibited improved seed set under high heat stress vs. the cultivated parent, whereas no IL was better than the cultivated parent in Pop 4. Under rainfed conditions at Hisar and Bawal, India, 19 ILs from Pop 3 and 16 ILs from Pop 4 showed significantly higher dry fodder yield than the cultivated parents. Further, screening of ILs for five diverse pathotype isolatesβ€”Pg 45, Pg 138, Pg 186, Pg 204, and Pg 232β€”of blast resulted in the identification of resistant ILs. Use of these promising ILs in breeding programs will assist in developing new varieties and hybrids with improved tolerance to biotic and abiotic stresses. The study indicated the genetic differences between the parents involved in crossing and also highlighted the importance of precise phenotyping of wild species for target trait prior to use in prebreeding work

    Molecular Evolution of the Two-Component System BvgAS Involved in Virulence Regulation in Bordetella

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    The whooping cough agent Bordetella pertussis is closely related to Bordetella bronchiseptica, which is responsible for chronic respiratory infections in various mammals and is occasionally found in humans, and to Bordetella parapertussis, one lineage of which causes mild whooping cough in humans and the other ovine respiratory infections. All three species produce similar sets of virulence factors that are co-regulated by the two-component system BvgAS. We characterized the molecular diversity of BvgAS in Bordetella by sequencing the two genes from a large number of diverse isolates. The response regulator BvgA is virtually invariant, indicating strong functional constraints. In contrast, the multi-domain sensor kinase BvgS has evolved into two different types. The pertussis type is found in B. pertussis and in a lineage of essentially human-associated B. bronchiseptica, while the bronchiseptica type is associated with the majority of B. bronchiseptica and both ovine and human B. parapertussis. BvgS is monomorphic in B. pertussis, suggesting optimal adaptation or a recent population bottleneck. The degree of diversity of the bronchiseptica type BvgS is markedly different between domains, indicating distinct evolutionary pressures. Thus, absolute conservation of the putative solute-binding cavities of the two periplasmic Venus Fly Trap (VFT) domains suggests that common signals are perceived in all three species, while the external surfaces of these domains vary more extensively. Co-evolution of the surfaces of the two VFT domains in each type and domain swapping experiments indicate that signal transduction in the periplasmic region may be type-specific. The two distinct evolutionary solutions for BvgS confirm that B. pertussis has emerged from a specific B. bronchiseptica lineage. The invariant regions of BvgS point to essential parts for its molecular mechanism, while the variable regions may indicate adaptations to different lifestyles. The repertoire of BvgS sequences will pave the way for functional analyses of this prototypic system

    The Type III Secreted Protein BspR Regulates the Virulence Genes in Bordetella bronchiseptica

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    Bordetella bronchiseptica is closely related with B. pertussis and B. parapertussis, the causative agents of whooping cough. These pathogenic species share a number of virulence genes, including the gene locus for the type III secretion system (T3SS) that delivers effector proteins. To identify unknown type III effectors in Bordetella, secreted proteins in the bacterial culture supernatants of wild-type B. bronchiseptica and an isogenic T3SS-deficient mutant were compared with iTRAQ-based, quantitative proteomic analysis method. BB1639, annotated as a hypothetical protein, was identified as a novel type III secreted protein and was designated BspR (Bordetella secreted protein regulator). The virulence of a BspR mutant (Ξ”bspR) in B. bronchiseptica was significantly attenuated in a mouse infection model. BspR was also highly conserved in B. pertussis and B. parapertussis, suggesting that BspR is an essential virulence factor in these three Bordetella species. Interestingly, the BspR-deficient strain showed hyper-secretion of T3SS-related proteins. Furthermore, T3SS-dependent host cell cytotoxicity and hemolytic activity were also enhanced in the absence of BspR. By contrast, the expression of filamentous hemagglutinin, pertactin, and adenylate cyclase toxin was completely abolished in the BspR-deficient strain. Finally, we demonstrated that BspR is involved in the iron-responsive regulation of T3SS. Thus, Bordetella virulence factors are coordinately but inversely controlled by BspR, which functions as a regulator in response to iron starvation
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