Screening of Trichoderma isolates for their potential of biosorption of nickel and cadmium.

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Nongmaithem, Nabakishor; Roy, Ayon; Bhattacharya, Prateek Madhab

2016-01-01

Fourteen Trichoderma isolates were evaluated for their tolerance to two heavy metals, nickel and cadmium. Three isolates, MT-4, UBT-18, and IBT-I, showed high levels of nickel tolerance, whereas MT-4, UBT-18, and IBT-II showed better tolerance of cadmium than the other isolates. Under nickel stress, biomass production increased up to a Ni concentration of 60ppm in all strains but then decreased as the concentrations of nickel were further increased. Among the nickel-tolerant isolates, UBT-18 produced significantly higher biomass upon exposure to nickel (up to 150ppm); however, the minimum concentration of nickel required to inhibit 50% of growth (MIC50) was highest in IBT-I. Among the cadmium-tolerant isolates, IBT-II showed both maximum biomass production and a maximum MIC50 value in cadmium stress. As the biomass of the Trichoderma isolates increased, a higher percentage of nickel removal was observed up to a concentration of 40ppm, followed by an increase in residual nickel and a decrease in biomass production at higher nickel concentrations in the medium. The increase in cadmium concentrations resulted in a decrease in biomass production and positively correlated with an increase in residual cadmium in the culture broth. Nickel and cadmium stress also influenced the sensitivity of the Trichoderma isolates to soil fungistasis. Isolates IBT-I and UBT-18 were most tolerant to fungistasis under nickel and cadmium stress, respectively. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Human and Animal Isolates of Yersinia enterocolitica Show Significant Serotype-Specific Colonization and Host-Specific Immune Defense Properties

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Schaake, Julia; Kronshage, Malte; Uliczka, Frank; Rohde, Manfred; Knuuti, Tobias; Strauch, Eckhard; Fruth, Angelika; Wos-Oxley, Melissa

2013-01-01

Yersinia enterocolitica is a human pathogen that is ubiquitous in livestock, especially pigs. The bacteria are able to colonize the intestinal tract of a variety of mammalian hosts, but the severity of induced gut-associated diseases (yersiniosis) differs significantly between hosts. To gain more information about the individual virulence determinants that contribute to colonization and induction of immune responses in different hosts, we analyzed and compared the interactions of different human- and animal-derived isolates of serotypes O:3, O:5,27, O:8, and O:9 with murine, porcine, and human intestinal cells and macrophages. The examined strains exhibited significant serotype-specific cell binding and entry characteristics, but adhesion and uptake into different host cells were not host specific and were independent of the source of the isolate. In contrast, survival and replication within macrophages and the induced proinflammatory response differed between murine, porcine, and human macrophages, suggesting a host-specific immune response. In fact, similar levels of the proinflammatory cytokine macrophage inflammatory protein 2 (MIP-2) were secreted by murine bone marrow-derived macrophages with all tested isolates, but the equivalent interleukin-8 (IL-8) response of porcine bone marrow-derived macrophages was strongly serotype specific and considerably lower in O:3 than in O:8 strains. In addition, all tested Y. enterocolitica strains caused a considerably higher level of secretion of the anti-inflammatory cytokine IL-10 by porcine than by murine macrophages. This could contribute to limiting the severity of the infection (in particular of serotype O:3 strains) in pigs, which are the primary reservoir of Y. enterocolitica strains pathogenic to humans. PMID:23959720

Human isolates of Salmonella enterica serovar Typhimurium from Taiwan displayed significantly higher levels of antimicrobial resistance than those from Denmark.

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Torpdahl, Mia; Lauderdale, Tsai-Ling; Liang, Shiu-Yun; Li, Ishien; Wei, Sung-Hsi; Chiou, Chien-Shun

2013-02-01

Salmonella enterica serovar Typhimurium is a major zoonotic pathogen with a high prevalence of antimicrobial resistance. This pathogen can disseminate across borders and spread far distances via the food trade and international travel. In this study, we compared the genotypes and antimicrobial resistance of 378 S. Typhimurium isolates collected in Taiwan and Denmark between 2009 and 2010. Genotyping revealed that many S. Typhimurium strains were concurrently circulating in Taiwan, Denmark and other countries in 2009 and 2010. When compared to the isolates collected from Denmark, the isolates from Taiwan displayed a significantly higher level of resistance to 11 of the 12 tested antimicrobials. Seven genetic clusters (A-G) were designated for the isolates. A high percentage of the isolates in genetic clusters C, F and G were multidrug-resistant. Of the isolates in cluster C, 79.2% were ASSuT-resistant, characterized by resistance to ampicillin, streptomycin, sulfamethoxazole, and tetracycline. In cluster F, 84.1% of the isolates were ACSSuT-resistant (resistant to ASSuT and chloramphenicol). Cluster G was unique to Taiwan and characterized in most isolates by the absence of three VNTRs (ST20, ST30 and STTR6) as well as a variety of multidrug resistance profiles. This cluster exhibited very high to extremely high levels of resistance to several first-line drugs, and among the seven clusters, it displayed the highest levels of resistance to cefotaxime and ceftazidime, ciprofloxacin and gentamicin. The high prevalence of antimicrobial resistance in S. Typhimurium from Taiwan highlights the necessity to strictly regulate the use of antimicrobials in the agriculture and human health care sectors. Copyright © 2012 Elsevier B.V. All rights reserved.

Prevention of reperfusion lung injury by lidocaine in isolated rat lung ventilated with higher oxygen levels.

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Das K

2003-01-01

Full Text Available BACKGROUND: Lidocaine, an antiarrhythmic drug has been shown to be effective against post-ischaemic reperfusion injury in heart. However, its effect on pulmonary reperfusion injury has not been investigated. AIMS: We investigated the effects of lidocaine on a postischaemic reperfused rat lung model. MATERIALS AND METHODS: Lungs were isolated and perfused at constant flow with Krebs-Henseilet buffer containing 4% bovine serum albumin, and ventilated with 95% oxygen mixed with 5% CO2. Lungs were subjected to ischaemia by stopping perfusion for 60 minutes followed by reperfusion for 10 minutes. Ischaemia was induced in normothermic conditions. RESULTS: Postischaemic reperfusion caused significant (p < 0.0001 higher wet-to-dry lung weight ratio, pulmonary arterial pressure and peak airway pressure compared to control lungs. Lidocaine, at a dose of 5mg/Kg b.w. was found to significantly (p < 0.0001 attenuate the increase in the wet-to-dry lung weight ratio, pulmonary arterial pressure and peak airway pressure observed in post-ischaemic lungs. CONCLUSION: Lidocaine is effective in preventing post-ischaemic reperfusion injury in isolated, perfused rat lung.

Different Babesia canis isolates, different diseases.

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Schetters, T P; Moubri, K; Précigout, E; Kleuskens, J; Scholtes, N C; Gorenflot, A

1997-11-01

Using surface immunofluorescence isolate-specific antigens were detected on the membrane of erythrocytes infected with Babesia parasites. In addition, the strains reacted differently with Plasmagel in that the European isolate (B.c. canis) could be purified on Plasmagel effectively, whereas infected erythrocytes of the South-African isolate (B.c. rossi) could not. Experimental infection of dogs with Babesia canis isolates from geographically different areas revealed different pathology. The European isolate obtained from France exhibited transient parasitaemia, usually below 1%, associated with low PCV values and congestion of internal organs. Clinical disease was correlated with an effect on the coagulation system, and not with peripheral parasitaemia. Infection of dogs with South-African-derived isolate induced high parasitaemia usually much higher than 1%, which required chemotherapeutic treatment. In these animals clinical disease was correlated with peripheral parasitaemia and not with parameters of the coagulation system. The results show that the etiology of disease caused by these isolates of B.c. canis and B.c. rossi is different. This might have implications for the development of vaccines against these infections.

Academically Ambitious and Relevant Higher Education Research: The Legacy of the Consortium of Higher Education Researchers

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Teichler, Ulrich

2013-01-01

The Consortium of Higher Education Researchers (CHER) was founded in 1988 to stimulate international communication and collaboration of higher education researchers. A need was felt to offset the isolation of the small numbers of scholars in this area of expertise in many countries, as well as the isolation of individual disciplines addressing…

Characterisation of successive Acinetobacter baumannii isolates from a deceased haemophagocytic lymphohistiocytosis patient.

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Choi, Hyeon Jin; Kil, Min Cheol; Choi, Ji-Young; Kim, Sun Ju; Park, Ki-Sup; Kim, Yae-Jean; Ko, Kwan Soo

2017-01-01

In this study, 38 Acinetobacter baumannii isolates successively isolated from blood, skin swabs and tracheal aspirates from a single patient who died from haemophagocytic lymphohistiocytosis were investigated. The isolates were collected between March 2012 and August 2012. A. baumannii genotypes were determined by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). In vitro antimicrobial susceptibility testing was performed and colistin heteroresistance and persistence were evaluated. The structure of AbaR resistance islands was explored, and serum sensitivity was determined. Based on MLST analysis, all 38 A. baumannii isolates showed the same sequence type (ST138). However, PFGE analysis showed that isolates from blood samples belonged to different genotypes depending on the isolation time: whilst blood isolates obtained at the early stages showed restriction patterns similar to those of isolates from other sources, isolates obtained at later stages exhibited a distinct pattern. All isolates were resistant to imipenem, cefepime, ciprofloxacin and piperacillin/tazobactam. Five isolates from tracheal aspirates and one from a skin swab were resistant to polymyxins, and two isolates from skin swabs and one from another source were non-susceptible to tigecycline. All colistin-susceptible isolates showed heteroresistance to colistin, and four were persisters. Isolates from blood showed higher survival rates against human serum than those from other sources. This study shows that the patient was infected with more than one A. baumannii strain. Heteroresistance, persistence or evasion of the innate immune response may explain the failure of antimicrobial treatments in this patient. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Characterization of Trypanosoma brucei gambiense stocks isolated ...

African Journals Online (AJOL)

Trypanosoma brucei gambiense was isolated twice from each of 23 patients in Côte d'Ivoire. Genetic characterization using RAPD (Random Primed Amplified Polymorphic DNA) showed additional variability within a given isoenzyme profile (zymodeme), confirming that this fingerprinting method has a higher discriminative ...

The invasive wetland plant Alternanthera philoxeroides shows a higher tolerance to waterlogging than its native Congener Alternanthera sessilis.

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Yue Chen

Full Text Available Plant invasion is one of the major threats to natural ecosystems. Phenotypic plasticity is considered to be important for promoting plant invasiveness. High tolerance of stress can also increase survival of invasive plants in adverse habitats. Limited growth and conservation of carbohydrate are considered to increase tolerance of flooding in plants. However, few studies have examined whether invasive species shows a higher phenotypic plasticity in response to waterlogging or a higher tolerance of waterlogging (lower plasticity than native species. We conducted a greenhouse experiment to compare the growth and morphological and physiological responses to waterlogging of the invasive, clonal, wetland species Alternanthera philoxeroides with those of its co-occurring, native, congeneric, clonal species Alternanthera sessilis. Plants of A. philoxeroides and A. sessilis were subjected to three treatments (control, 0 and 60 cm waterlogging. Both A. philoxeroides and A. sessilis survived all treatments. Overall growth was lower in A. philoxeroides than in A. sessilis, but waterlogging negatively affected the growth of A. philoxeroides less strongly than that of A. sessilis. Alternanthera philoxeroides thus showed less sensitivity of growth traits (lower plasticity and higher waterlogging tolerance. Moreover, the photosynthetic capacity of A. philoxeroides was higher than that of A. sessilis during waterlogging. Alternanthera philoxeroides also had higher total non-structural and non-soluble carbohydrate concentrations than A. sessilis at the end of treatments. Our results suggest that higher tolerance to waterlogging and higher photosynthetic capacity may partly explain the invasion success of A. philoxeroides in wetlands.

Hanseniaspora uvarum from winemaking environments show spatial and temporal genetic clustering

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Warren eAlbertin

2016-01-01

Full Text Available Hanseniaspora uvarum is one of the most abundant yeast species found on grapes and in grape must, at least before the onset of alcoholic fermentation which is usually performed by Saccharomyces species. The aim of this study was to characterise the genetic and phenotypic variability within the H. uvarum species. One hundred and fifteen strains isolated from winemaking environments in different geographical origins were analysed using 11 microsatellite markers and a subset of 47 strains were analysed by AFLP. H. uvarum isolates clustered mainly on the basis of their geographical localisation as revealed by microsatellites. In addition, a strong clustering based on year of isolation was evidenced, indicating that the genetic diversity of Hanseniaspora uvarum isolates was related to both spatial and temporal variations. Conversely, clustering analysis based on AFLP data provided a different picture with groups showing no particular characteristics, but provided higher strain discrimination. This result indicated that AFLP approaches are inadequate to establish the genetic relationship between individuals, but allowed good strain discrimination. At the phenotypic level, several extracellular enzymatic activities of enological relevance (pectinase, chitinase, protease, β-glucosidase were measured but showed low diversity. The impact of environmental factors of enological interest (temperature, anaerobia and copper addition on growth was also assessed and showed poor variation. Altogether, this work provided both new analytical tool (microsatellites and new insights into the genetic and phenotypic diversity of H. uvarum, a yeast species that has previously been identified as a potential candidate for co-inoculation in grape must, but whose intraspecific variability had never been fully assessed.

Hydrocarbon-degradation by Isolate Pseudomonas lundensis UTAR FPE2

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Adeline, S. Y. Ting

2009-01-01

Full Text Available In this study, the potential of isolate Pseudomonas lundensis UTAR FPE2 as a hydrocarbon degrader was established. Their biodegradation activity was first detected with the formation of clearing zones on Bushnell-Hass agar plates, with the largest diameter observed on plates supplemented with paraffin, followed by mineral oil and petrol. Utilization of hydrocarbon sources were again detected in broth cultures supplemented with similar hydrocarbon substrates, where the mean viable cell count recovered from hydrocarbon-supplemented broth cultures were higher than the initial inoculum except for napthalene. In both tests, the isolate showed higher degradability towards aliphatic hydrocarbon sources, and the least activity towards the aromatic hydrocarbon naphthalene. The isolate P. lundensis UTAR FPE2 (8 log10 cfu/mL also degraded crude diesel sample, with 69% degradation during the first three days. To conclude, this study suggests the potential use of this isolate for bioremediation of hydrocarbon-contaminated environments.

Isolation, Identification, and Xanthine Oxidase Inhibition Activity of Alkaloid Compound from Peperomia pellucida

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Fachriyah, E.; Ghifari, M. A.; Anam, K.

2018-04-01

The research of the isolation and xanthine oxidation inhibition activity of alkaloid compound from Peperomia pellucida has been carried out. Alkaloid extract is isolated by column chromatography and preparative TLC. Alkaloid isolate is identified spectroscopically by UV-Vis spectrophotometer, FT-IR, and LC-MS/MS. Xanthine oxidase inhibition activity is carried out by in vitro assay. The result showed that the alkaloid isolated probably has piperidine basic structure. The alkaloid isolate has N-H, C-H, C = C, C = O, C-N, C-O-C groups and the aromatic ring. The IC50 values of ethanol and alkaloid extract are 71.6658 ppm and 76.3318 ppm, respectively. Alkaloid extract of Peperomia pellucida showed higher activity than ethanol extract.

Characterization of lactococci isolated from homemade kefir

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Kojić M.

2007-01-01

Full Text Available Five bacteriocin-producing lactococci isolates from traditionally prepared kefir were determined as Lactococcus lactis subsp. lactis. The analyzed isolates showed different plasmid profiles and no cross inhibition between them was detected. Moreover, natural isolate BGKF26 was resistant to the antimicrobial activity of nisin producing strain NP45. Plasmid curing experiments revealed that the genes encoding bacteriocin and proteinase production are located on separate genetic elements, except in BGKF26. Production of the tested bacteriocins depends on the concentration of casitone or triptone in the medium. Higher concentrations of casitone or triptone induce bacteriocin activity. Our DNA-DNA hybridization analyses suggest that the analyzed antimicrobial compounds probably are lactococcin-like bacteriocins.

Comparison of Microbiological and Probiotic Characteristics of Lactobacilli Isolates from Dairy Food Products and Animal Rumen Contents

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Neethu Maria Jose

2015-04-01

Full Text Available Lactobacilli are employed in probiotic food preparations and as feed additives in poultry and livestock, due to health benefits associated with their consumption. The objective of this study was to evaluate and compare the probiotic potential of ten lactobacilli strains isolated from commercial dairy food products and animal rumen contents in New Zealand. Genetic identification of the isolates revealed that all belonged to the genus Lactobacillus, specifically the species L. reuteri, L. rhamnosus and L. plantarum. All isolates did not show any haemolytic behaviour. Isolates of dairy origin showed better tolerance to low pH stress. On the other hand, rumen isolates exhibited a higher tolerance to presence of bile salts. All isolates exhibited resistance to aminoglycoside antibiotics, however most were sensitive to ampicillin. Isolates of rumen origin demonstrated a higher inhibitory effect on Listeria monocytogenes, Enterobacter aerogenes and Salmonella menston. Bacterial adherence of all isolates increased with a decrease in pH. This screening study on lactobacilli isolates has assessed and identified potential probiotic candidates for further evaluation.

[Study on VNTR diversity of clinical Mycobacterium tuberculosis isolates from Qinghai].

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Li, Bin; Liu, Haican; Wang, Zhaofen; Ma, Yongcheng; Su, Xiaodong; Jiang, Mingxia; Wan, Kanglin; Liu, Shou; Zhao, Xiuqin; Qu, Shugen

2015-10-01

To investigate the variable number tandem repeats (VNTR) genetic polymorphisms, genotyping and distribution pattern of clinical Mycobacterium (M.) tuberculosis isolates from Qinghai province. The clinical M. tuberculosis strains isolated from the patients with tuberculosis and related background data were collected from Qinghai Provincial Center for Disease Control and Prevention from 2009 to 2012. Genotyping was conducted by using multiple locus VNTR analysis (MLVA). Genomic DNA was extracted and 15 VNTR loci were amplified with PCR and the PCR products were detected with gel electrophoresis. The VNTR diversity and clusters of genotyping were analyzed with BioNumerics (Version 5.0). A total of 251 clinical M. tuberculosis isolates were analyzed with 15 VNTR loci showing that there were great genetic diversity in these isolates. Six of the 15 VNTR loci, showed that the Hunter-Gaston index (HGI) were higher than 0.6, in which the highest resolution was MIRU26. The clusters of genotyping showed that these isolates could be categorized into four gene clusters and 238 genotypes. The four gene clusters accounted for 4.9%, 91.9%, 1.6% and 1.6% of the clinical isolates, respectively. The results showed that there is great variety of VNTR genetic polymorphisms in clinical M. tuberculosis isolates in Qinghai province.

Isolation of human simple repeat loci by hybridization selection.

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Armour, J A; Neumann, R; Gobert, S; Jeffreys, A J

1994-04-01

We have isolated short tandem repeat arrays from the human genome, using a rapid method involving filter hybridization to enrich for tri- or tetranucleotide tandem repeats. About 30% of clones from the enriched library cross-hybridize with probes containing trimeric or tetrameric tandem arrays, facilitating the rapid isolation of large numbers of clones. In an initial analysis of 54 clones, 46 different tandem arrays were identified. Analysis of these tandem repeat loci by PCR showed that 24 were polymorphic in length; substantially higher levels of polymorphism were displayed by the tetrameric repeat loci isolated than by the trimeric repeats. Primary mapping of these loci by linkage analysis showed that they derive from 17 chromosomes, including the X chromosome. We anticipate the use of this strategy for the efficient isolation of tandem repeats from other sources of genomic DNA, including DNA from flow-sorted chromosomes, and from other species.

Composition, structure and functional properties of protein concentrates and isolates produced from walnut (Juglans regia L.).

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Mao, Xiaoying; Hua, Yufei

2012-01-01

In this study, composition, structure and the functional properties of protein concentrate (WPC) and protein isolate (WPI) produced from defatted walnut flour (DFWF) were investigated. The results showed that the composition and structure of walnut protein concentrate (WPC) and walnut protein isolate (WPI) were significantly different. The molecular weight distribution of WPI was uniform and the protein composition of DFWF and WPC was complex with the protein aggregation. H(0) of WPC was significantly higher (p structure of WPI was similar to WPC. WPI showed big flaky plate like structures; whereas WPC appeared as a small flaky and more compact structure. The most functional properties of WPI were better than WPC. In comparing most functional properties of WPI and WPC with soybean protein concentrate and isolate, WPI and WPC showed higher fat absorption capacity (FAC). Emulsifying properties and foam properties of WPC and WPI in alkaline pH were comparable with that of soybean protein concentrate and isolate. Walnut protein concentrates and isolates can be considered as potential functional food ingredients.

Comparison of chickpea rhizobia isolates from diverse Portuguese natural populations based on symbiotic effectiveness and DNA fingerprint.

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Laranjo, M; Branco, C; Soares, R; Alho, L; Carvalho, M D E; Oliveira, S

2002-01-01

To test the hypothesis that differences in chickpea yields obtained in four distinct Portuguese regions (Beja, Elvas-Casas Velhas, Elvas-Estação Nacional de Melhoramento de Plantas (ENMP) and Evora) could be due to variation between the natural rhizobia populations. Estimation of the size of the different rhizobial populations showed that Elvas-ENMP population was the largest one. Elvas-ENMP population also revealed a higher proportion of isolates carrying more than one plasmid. Assessment of genetic diversity of the native rhizobia populations by a DNA fingerprinting PCR method, here designated as DAPD (Direct Amplified Polymorphic DNA), showed a higher degree of variation in Elvas-ENMP and Beja populations. The symbiotic effectiveness (SE) of 39 isolates was determined and ranged 13-34%. Statistical analysis showed that SE was negatively correlated with plasmid number of the isolate. The largest indigenous rhizobia population was found in Elvas-ENMP. DAPD pattern and plasmid profile analysis both suggested a higher genetic diversity among the populations of Elvas-ENMP and Beja. No relationship was found between SE of the isolates and their origin site. The large native population, rather than the symbiotic performance of individual rhizobia, could contribute to the higher chickpea yields obtained in Elvas-ENMP.

Isolation and characterization of Pseudomonas putida WLY for ...

African Journals Online (AJOL)

Using the BMM medium containing 100 mg/L of reactive brilliant red X-3B, a decolorizing bacterium with higher decolorization activity was isolated and it showed a decolorization zone of 10 mm; this decolorizing bacterium was identified as Pseudomonas putida WLY based on physiological and biochemical characteristics ...

Microsatellite typing of clinical and environmental Cryptococcus neoformans var. grubii isolates from Cuba shows multiple genetic lineages.

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Maria-Teresa Illnait-Zaragozi

Full Text Available BACKGROUND: Human cryptococcal infections have been associated with bird droppings as a likely source of infection. Studies toward the local and global epidemiology of Cryptococcus spp. have been hampered by the lack of rapid, discriminatory, and exchangeable molecular typing methods. METHODOLOGY/PRINCIPAL FINDINGS: We selected nine microsatellite markers for high-resolution fingerprinting from the genome of C. neoformans var. grubii. This panel of markers was applied to a collection of clinical (n = 122 and environmental (n = 68; from pigeon guano C. neoformans var. grubii isolates from Cuba. All markers proved to be polymorphic. The average number of alleles per marker was 9 (range 5-51. A total of 104 genotypes could be distinguished. The discriminatory power of this panel of markers was 0.993. Multiple clusters of related genotypes could be discriminated that differed in only one or two microsatellite markers. These clusters were assigned as microsatellite complexes. The majority of environmental isolates (>70% fell into 1 microsatellite complex containing only few clinical isolates (49 environmental versus 2 clinical. Clinical isolates were segregated over multiple microsatellite complexes. CONCLUSIONS/SIGNIFICANCE: A large genotypic variation exists in C. neoformans var. grubii. The genotypic segregation between clinical and environmental isolates from pigeon guano suggests additional source(s of human cryptococcal infections. The selected panel of microsatellite markers is an excellent tool to study the epidemiology of C. neoformans var. grubii.

Dihydrochalcone Compounds Isolated from Crabapple Leaves Showed Anticancer Effects on Human Cancer Cell Lines

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Xiaoxiao Qin

2015-11-01

Full Text Available Seven dihydrochalcone compounds were isolated from the leaves of Malus crabapples, cv. “Radiant”, and their chemical structures were elucidated by UV, IR, ESI-MS, 1H-NMR and 13C-NMR analyses. These compounds, which include trilobatin (A1, phloretin (A2, 3-hydroxyphloretin (A3, phloretin rutinoside (A4, phlorizin (A5, 6′′-O-coumaroyl-4′-O-glucopyranosylphloretin (A6, and 3′′′-methoxy-6′′-O-feruloy-4′-O-glucopyranosyl-phloretin (A7, all belong to the phloretin class and its derivatives. Compounds A6 and A7 are two new rare dihydrochalcone compounds. The results of a MTT cancer cell growth inhibition assay demonstrated that phloretin and these derivatives showed significant positive anticancer activities against several human cancer cell lines, including the A549 human lung cancer cell line, Bel 7402 liver cancer cell line, HepG2 human ileocecal cancer cell line, and HT-29 human colon cancer cell line. A7 had significant effects on all cancer cell lines, suggesting potential applications for phloretin and its derivatives. Adding a methoxyl group to phloretin dramatically increases phloretin’s anticancer activity.

Toxigenic Corynebacterium ulcerans isolated from a free-roaming red fox (Vulpes vulpes).

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Sting, Reinhard; Ketterer-Pintur, Sandra; Contzen, Matthias; Mauder, Norman; Süss-Dombrowski, Christine

2015-01-01

Corynebacterium (C.) ulcerans could be isolated from the spleen of a red fox (Vulpes vulpes) that had been found dead in the state of Baden-Württemberg, Germany. Pathohistological examination suggested that the fox had died of distemper, as was confirmed by PCR. The isolate was identified biochemically, by MALDI-TOF MS, FT-IR and by partial 16S rRNA, rpoB and tox gene sequencing. Using the Elek test the C. ulcerans isolate demonstrated diphtheria toxin production. FT-IR and sequencing data obtained from the C. ulcerans isolate from the red fox showed higher similarity to isolates from humans than to those from wild game.

Educational Pathways to Remote Employment in Isolated Communities

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David Denkenberger

2015-01-01

Full Text Available Those who live in isolated communities often lack reliable, skilled employment opportunities, which fundamentally undermines their human security. For individuals who wish to remain in their isolated communities for family, religious, philosophical or other reasons, their attachment to their communities creates a disincentive for higher education. This promotes low educational achievement, which in turn results in low socioeconomic status, lack of social mobility, and a generational cycle of poverty. The human misery that results from such a feedback loop is observed in isolated communities throughout North America, including aboriginal communities in Canada. Fortunately, maturation of information and communication technologies now offers individuals the potential to gain high-skilled employment while living in an isolated community, using both (i virtual work/remote work and (ii remote training and education. To examine that potential, this study: 1 categorizes high-skill careers that demand a higher education and are widely viable for remote work, 2 examines options for obtaining the required education remotely, and 3 performs an economic analysis of investing in remote education, quantifying the results in return on investment. The results show that the Internet has now opened up the possibility of both remote education and remote work. Though the investment in college education is significant, there are loans available and the return on investment is generally far higher than the interest rate on the loans. The results identified several particularly promising majors and dozens of high-income careers. The ability to both obtain an education and employment remotely offers the potential to lift many people living in isolated communities out of poverty, reduce inequality overall, and provide those living in isolated communities with viable means of employment security, which not only allows personal sustainability, but also the potential for

Degradation and depolymerization of plastic waste by local bacterial isolates and bubble column reactor

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Hussein, Amal A.; Alzuhairi, Mohammed; Aljanabi, Noor H.

2018-05-01

Accumulation of plastics, especially Polyethylene terephthalate (PET), is an ever increasing ecological threat due to its excessive usage in everyday human life. Nowadays, there are many methods to get rid of plastic wastes including burning, recycling and burying. However, these methods are not very active since their long period, anaerobic conditions that increase the rate of toxic materials released into the environment. This work aims to study the biological degradation of PET microorganism isolated from soil sample. Thirty eight (38) bacterial isolates were isolated from ten soil and plastic waste sample collected from four different waste disposal sites in Baghdad city during different periods between December 2016 and March 2017. Isolation was performed using enrichment culture method (flasks method) by culturing the soil samples in flasks with MSM medium where there is no carbon source only PET. Results showed that Al-Za'farania sample gave a higher number of isolates (13 isolates), while other samples gave less number of isolates. Screening was performed depending on their ability to grow in liquid MSM which contains PET powder and pieces and change the color of the PET-emulsified liquid medium as well as their ability to form the clear zone on PET-MSM agar. The results showed that NH-D-1 isolate has the higher ability to degrade DPET and PET pieces. According to morphological, biochemical characterization and Vitek-2 technique, the most active isolate was identified as Acinetobacter baumannii.

Isolated vertigo and possibility of brain ischemia.

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Mosarrezai, Arash; Toghae, Mansoureh; Majed, Masoud; Aloosh, Mehdi

2012-08-01

In cases of isolated vertigo, physicians are unable to definitely distinguish between central or peripheral vertigo by history and physical examination. Some central causes of isolated vertigo such as cerebellar stroke can be life-threatening and require intervention. Brain infarction can be detected shortly after the onset of clinical symptoms by using diffusion-weighted MRI (DWI). We have conducted this study to perform DWI on isolated vertigo patients with a higher probability of brain infarction. We enrolled 55 consecutive patients with isolated vertigo who had at least one cardiovascular risk factor. A questionnaire that consisted of cardiovascular risk factors was completed and DWI performed for each patient. We analyzed the association of cardiovascular risk factors with infarction as identified by DWI. Using DWI, 5 (9.1%) patients had an acute ischemic stroke. Among cardiovascular risk factors, analysis showed a significant relationship between diabetes mellitus (DM) and infarction. Isolated vertigo may occur due to the occlusion of a small artery in the area of brain circulated by the posterior inferior cerebellar artery. According to our results, DWI may be used in diabetic patients with isolated vertigo to locate a probable infarction.

Serological characterisation of foot-and-mouth disease type 'O' field isolates from Peru: 1992-1994

International Nuclear Information System (INIS)

Espinoza, A.M.

1998-01-01

Nineteen field isolates of foot-and-mouth disease Virus (FMDV) recovered from bovine epithelial samples corresponding to outbreaks present in different regions of Peru, between 1992-1994 were studied. The relationship of the virus isolates to the O/Urubamba vaccine strain of Peru was determined by the calculation of the 'r' values obtained by the liquid-phase blocking ELISA. All the isolates showed 'r' values higher than 0.66 indicating that the vaccine strain should protect against the field strains. Characterization of the field isolates by a trapping ELISA using a panel of monoclonal antibodies against FMDV O/Switzerland and O/Caseros, showed slight differences in the profiles of the field isolates when compared with the O/Urubamba vaccine strain, but no differences were found among all the isolates. (author)

Fibroblasts maintained in 3 dimensions show a better differentiation state and higher sensitivity to estrogens

Energy Technology Data Exchange (ETDEWEB)

Montani, Claudia [Laboratory of Biotechnology, Department of Laboratory Medicine, Civic Hospital of Brescia (Italy); Steimberg, Nathalie; Boniotti, Jennifer [Laboratory of Tissue Engineering, Anatomy and Physiopathology Unit, Department of Clinical and Experimental Sciences, School of Medicine, University of Brescia (Italy); Biasiotto, Giorgio; Zanella, Isabella [Laboratory of Biotechnology, Department of Laboratory Medicine, Civic Hospital of Brescia (Italy); Department of Molecular and Translational Medicine, University of Brescia, Brescia (Italy); Diafera, Giuseppe [Integrated Systems Engineering (ISE), Milan (Italy); Biunno, Ida [IRGB-CNR, Milan (Italy); IRCCS-Multimedica, Milan (Italy); Caimi, Luigi [Laboratory of Biotechnology, Department of Laboratory Medicine, Civic Hospital of Brescia (Italy); Department of Molecular and Translational Medicine, University of Brescia, Brescia (Italy); Mazzoleni, Giovanna [Laboratory of Tissue Engineering, Anatomy and Physiopathology Unit, Department of Clinical and Experimental Sciences, School of Medicine, University of Brescia (Italy); Di Lorenzo, Diego, E-mail: diego.dilorenzo@yahoo.it [Laboratory of Biotechnology, Department of Laboratory Medicine, Civic Hospital of Brescia (Italy)

2014-11-01

Cell differentiation and response to hormonal signals were studied in a 3D environment on an in-house generated mouse fibroblast cell line expressing a reporter gene under the control of estrogen responsive sequences (EREs). 3D cell culture conditions were obtained in a Rotary Cell Culture System; (RCCS™), a microgravity based bioreactor that promotes the aggregation of cells into multicellular spheroids (MCS). In this bioreactor the cells maintained a better differentiated phenotype and more closely resembled in vivo tissue. The RCCS™ cultured fibroblasts showed higher expression of genes regulating cell assembly, differentiation and hormonal functions. Microarray analysis showed that genes related to cell cycle, proliferation, cytoskeleton, migration, adhesion and motility were all down-regulated in 3D as compared to 2D conditions, as well as oncogene expression and inflammatory cytokines. Controlled remodeling of ECM, which is an essential aspect of cell organization, homeostasis and tissue was affected by the culture method as assessed by immunolocalization of β-tubulin. Markers of cell organization, homeostasis and tissue repair, metalloproteinase 2 (MMP2) and its physiological inhibitor (TIMP4) changed expression in association with the relative formation of cell aggregates. The fibroblasts cultured in the RCCS™ maintain a better responsiveness to estrogens, measured as expression of ERα and regulation of an ERE-dependent reporter and of the endogenous target genes CBP, Rarb, MMP1 and Dbp. Our data highlight the interest of this 3D culture model for its potential application in the field of cell response to hormonal signals and the pharmaco-toxicological analyses of chemicals and natural molecules endowed of estrogenic potential. - Highlights: • We here characterized the first cell line derived from an estrogen reporter mouse. • In the RCCS cells express an immortalized behavior but not a transformed phenotype. • The RCCS provides a system for

Isolation and identification of Profenofos degrading bacteria

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Saadatullah Malghani

2009-12-01

Full Text Available An enrichment culture technique was used to isolate bacterial strains responsible for the biodegradation of profenofos in a soil from Hubei province of central China. Two pure bacterial cultures, named W and Y, were isolated and subsequently characterized by sequencing of 16S rRNA genes and biochemical tests. Isolate W showed 96% similarity to the 16S rRNA gene of a Pseudomonas putida unlike Y which showed 99% similarity to the 16S rRNA gene of Burkholderia gladioli. Both strains grew well at pH 5.5-7.2 with a broad temperature profile ranging from 28º to 36 ºC. Bioremediation of profenofos-contaminated soil was examined using soil treated with 200 ug g-1; profenofos resulted in a higher degradation rate than control soils without inoculation. In a mineral salt medium (FTW reduction in profenofos concentration was 90% within 96 hours of incubation. A literature survey revealed that no data is available regarding the role of Burkholderia gladioli on pesticide biodegradation as well as on profenofos.

MATLAB-based algorithm to estimate depths of isolated thin dike-like sources using higher-order horizontal derivatives of magnetic anomalies.

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Ekinci, Yunus Levent

2016-01-01

This paper presents an easy-to-use open source computer algorithm (code) for estimating the depths of isolated single thin dike-like source bodies by using numerical second-, third-, and fourth-order horizontal derivatives computed from observed magnetic anomalies. The approach does not require a priori information and uses some filters of successive graticule spacings. The computed higher-order horizontal derivative datasets are used to solve nonlinear equations for depth determination. The solutions are independent from the magnetization and ambient field directions. The practical usability of the developed code, designed in MATLAB R2012b (MathWorks Inc.), was successfully examined using some synthetic simulations with and without noise. The algorithm was then used to estimate the depths of some ore bodies buried in different regions (USA, Sweden, and Canada). Real data tests clearly indicated that the obtained depths are in good agreement with those of previous studies and drilling information. Additionally, a state-of-the-art inversion scheme based on particle swarm optimization produced comparable results to those of the higher-order horizontal derivative analyses in both synthetic and real anomaly cases. Accordingly, the proposed code is verified to be useful in interpreting isolated single thin dike-like magnetized bodies and may be an alternative processing technique. The open source code can be easily modified and adapted to suit the benefits of other researchers.

Isolated galaxies

International Nuclear Information System (INIS)

Einasto, Maret

1990-01-01

To test for the possible presence of really isolated galaxies, which form a randomly distributed population in voids, we compare the distribution of most isolated galaxies in an observed sample with distributions of the same number of random points using the nearest neighbour test. The results show that the random population of really isolated galaxies does not exist - even the most isolated galaxies are connected with systems of galaxies, forming their outlying parts. (author)

Analysis of pathogenic factors of Proteus mirabilis isolated from urinary tract infection

OpenAIRE

室谷,勝久

1991-01-01

Proteus mirabilis has several pathogenic factors such as adherent ability to urinary tract epitherial cells, urease, motility and resistance to urine. The pathogenic activities of clinically isolated P. mirabilis were analyzed. Higher pathogenic strains (No. 25 and No. 30) which had morphologically different pili but had a higher density of pili showed strong adherent activity to bladder epithelial cells of mouse and rat. These strains also showed a clear chemotaxis to urinary tract tissue ex...

Genome analysis of environmental and clinical P. aeruginosa isolates from sequence type-1146.

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David Sánchez

Full Text Available The genomes of Pseudomonas aeruginosa isolates of the new sequence type ST-1146, three environmental (P37, P47 and P49 and one clinical (SD9 isolates, with differences in their antibiotic susceptibility profiles have been sequenced and analysed. The genomes were mapped against P. aeruginosa PAO1-UW and UCBPP-PA14. The allelic profiles showed that the highest number of differences were in "Related to phage, transposon or plasmid" and "Secreted factors" categories. The clinical isolate showed a number of exclusive alleles greater than that for the environmental isolates. The phage Pf1 region in isolate SD9 accumulated the highest number of nucleotide substitutions. The ORF analysis of the four genomes assembled de novo indicated that the number of isolate-specific genes was higher in isolate SD9 (132 genes than in isolates P37 (24 genes, P47 (16 genes and P49 (21 genes. CRISPR elements were found in all isolates and SD9 showed differences in the spacer region. Genes related to bacteriophages F116 and H66 were found only in isolate SD9. Genome comparisons indicated that the isolates of ST-1146 are close related, and most genes implicated in pathogenicity are highly conserved, suggesting a genetic potential for infectivity in the environmental isolates similar to the clinical one. Phage-related genes are responsible of the main differences among the genomes of ST-1146 isolates. The role of bacteriophages has to be considered in the adaptation processes of isolates to the host and in microevolution studies.

Group and Individual Variability in Mouse Pup Isolation Calls Recorded on the Same Day Show Stability

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Terra D. Barnes

2017-12-01

Full Text Available Mice produce ultrasonic vocalizations (USVs in a variety of social situations, and USVs have been leveraged to study many neurological diseases including verbal dyspraxia, depression, autism and stuttering. Pups produce isolation calls, a common USV, spontaneously when they are isolated from their mother during the first 2 weeks of life. Several genetic manipulations affect (and often reduce pup isolation calls in mice. To facilitate the use of this assay as a means of testing whether significant functional differences in genotypes exist instead of contextual differences, we test the variability inherent in many commons measures of mouse vocalizations. Here we use biological consistency as a way of determining which are reproducible in mouse pup vocalizations. We present a comprehensive analysis of the normal variability of these vocalizations in groups of mice, individual mice and different strains of mice. To control for maturation effects, we recorded pup isolation calls in the same group of C57BL/6J 5 days old mice twice, with 1 h of rest in between recordings. In almost all cases, the group averages between the first and second recordings were the same. We also found that there were high correlations in some parameters in individual mice across recording while others were not well correlated. These findings could be replicated for the majority of features in a separate group of C57BL/6J mice and a group of 129/SvEvBrd-C57BL/6J mice. The averages of these mouse USV features are highly consistent and represent a robust assay to test the effects of genetic and other interventions in the experimental setting.

Neurophysiological correlates of word processing deficits in isolated reading and isolated spelling disorders.

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Bakos, Sarolta; Landerl, Karin; Bartling, Jürgen; Schulte-Körne, Gerd; Moll, Kristina

2018-03-01

In consistent orthographies, isolated reading disorders (iRD) and isolated spelling disorders (iSD) are nearly as common as combined reading-spelling disorders (cRSD). However, the exact nature of the underlying word processing deficits in isolated versus combined literacy deficits are not well understood yet. We applied a phonological lexical decision task (including words, pseudohomophones, legal and illegal pseudowords) during ERP recording to investigate the neurophysiological correlates of lexical and sublexical word-processing in children with iRD, iSD and cRSD compared to typically developing (TD) 9-year-olds. TD children showed enhanced early sensitivity (N170) for word material and for the violation of orthographic rules compared to the other groups. Lexical orthographic effects (higher LPC amplitude for words than for pseudohomophones) were the same in the TD and iRD groups, although processing took longer in children with iRD. In the iSD and cRSD groups, lexical orthographic effects were evident and stable over time only for correctly spelled words. Orthographic representations were intact in iRD children, but word processing took longer compared to TD. Children with spelling disorders had partly missing orthographic representations. Our study is the first to specify the underlying neurophysiology of word processing deficits associated with isolated literacy deficits. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Phenotypic and Genotypic Resistance of Salmonella Isolates from Healthy and Diseased Pigs in China During 2008-2015.

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Jiu, Yueguang; Zhu, Shun; Khan, Sher Bahadar; Sun, Mengzhen; Zou, Geng; Meng, Xianrong; Wu, Bin; Zhou, Rui; Li, Shaowen

2017-07-01

The antimicrobial resistance of Salmonella strains is rapidly increasing worldwide, which poses significant threats to animal and public health. In this study, a total of 249 porcine Salmonella isolates collected in China during 2008-2015 were examined, including 155 clinical isolates from diseased pigs and 94 nonclinical isolates from healthy pigs. Based on the minimum inhibitory concentration of seven antimicrobial agents, 96.4% of the isolates were resistant to at least one of the tested antibiotics and 81.0% of them showed multidrug resistance. The highest antimicrobial resistance was observed for tetracycline (85.9%), and the lowest was found for cefotaxime (13.3%). The isolates from diseased pigs exhibited significantly higher levels of antimicrobial resistance than those from healthy pigs. Twenty-two isolates from healthy pigs were resistant to ciprofloxacin, which may inhibit the curative effectiveness of fluoroquinolones on bacterial food-borne poisoning and infections in humans caused by contaminated food. Moreover, cefotaxime resistance of the strains isolated from diseased pigs during 2013-2015 was significantly higher compared with the strains isolated during 2008-2010. Further study showed that the correlation between phenotypic and genotypic resistance varied among the isolates from different sources, and in many cases, the presence of resistance genes was not consistent with the resistance to the corresponding antimicrobials. These results are very significant for veterinary practice and public health.

Antimicrobial Activity of Cell Free Supernatant of Irradiated Lactic Acid Bacteria Isolates

International Nuclear Information System (INIS)

Abdelaleem, M.A.; AL-Hagar, O.E.Aa.

2015-01-01

Attempts were made to isolate bio preservatives using food wastes with no value and low cost. Whey is the raw material achieved that value. Whey and many other food wastes are used in our study to isolate Lactic acid bacteria (LAB). Cell free supernatants (CFS) of isolates are used to evaluate their antimicrobial activity against indicator pathogenic bacterial strains. CFS-9 isolate from whey has the highest inhibitory activity compared to all other isolates. The inhibitory activity of CFS-9, Nisin (400 IU / ml) and the standard Lactococcus Lactis Subsp. Lactis ATCC 11454 (Lacto) were determined. Furthermore, isolate-9 and Lacto strains were exposed to irradiation at different doses. The inhibition zones of; control isolate-9 (non-irradiated) showed the highest values against all indicator strains, CFS of irradiated Lacto at dose 250 Gy was the highest value against Bacillus cereus and Escherichia coli compared to other irradiation treatments, CFS of irradiated Lacto at dose 100 Gy was the highest value against Staph aureus, while the inhibition zone was in the highest value in CFS of irradiated Lacto at dose 500 Gy against Salmonella typhimurium. Nisin (400 IU / ml) was significantly higher than all CFS of irradiated isolate-9 while, the inhibition zones of all CFS-Lacto (irradiated and nonirradiated) are better and higher than nisin-400

Molecular characterization, fitness and mycotoxin production of benzimidazole-resistant isolates of Penicillium expansum.

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Malandrakis, Anastasios A; Markoglou, Anastasios N; Konstantinou, Sotiris; Doukas, Eleftherios G; Kalampokis, John F; Karaoglanidis, George S

2013-04-01

Penicillium expansum field-strains resistant to benzimidazole fungicides were isolated in high frequency from decayed apple fruit collected from packinghouses and processing industries located in the region of Imathia, N. Greece. In vitro fungitoxicity tests resulted in the identification of two different resistant phenotypes: highly (BEN-HR) and moderately (BEN-MR) carbendazim-resistant. Thirty seven percent of the isolated P. expansum strains belonged to the BEN-HR phenotype, carried no apparent fitness penalties and exhibited resistance levels higher than 60 based on EC50 values. Cross resistance studies with other benzimidazole fungicides showed that all BEN-HR and BEN-MR isolates were also less sensitive to benomyl and thiabendazole. Fungitoxicity tests on the response of BEN-HR isolates to fungicides belonging to other chemical classes revealed no cross-resistance relationships between benzimidazoles and the phenylpyrrole fludioxonil, the dicarboximide iprodione, the anilinopyrimidine cyprodinil, the QoI pyraclostrobin, the imidazole imazalil and the triazole tebuconazole, indicating that a target-site modification is probably responsible for the BEN-HR phenotype observed. Contrary to the above, some BEN-MR isolates exhibited an increased sensitivity to cyprodinil compared to benzimidazole-sensitive ones. BEN-MR isolates had fitness parameters similar to the benzimidazole-sensitive isolates except for conidia production which appeared significantly decreased. Analysis of mycotoxin production (patulin and citrinin) showed that all benzimidazole-resistant isolates produced mycotoxins at concentrations significantly higher than sensitive isolates both on culture medium and on artificially inoculated apple fruit. Comparison of the β-tubulin gene DNA sequence between resistant and sensitive isolates revealed a point mutation resulting from the E198A substitution of the corresponding protein in most but not all HR isolates tested. Molecular analysis of the �

Isolation, Characterization and Application of Bacterial Population From Agricultural Soil at Sohag Province, Egypt

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Bahig, A. E.

2008-01-01

Full Text Available Forty soil samples of agriculture soil were collected from two different sites in Sohag province, Egypt, during hot and cold seasons. Twenty samples were from soil irrigated with canal water (site A and twenty samples were from soil irrigated with wastewater (site B. This study aimed to compare the incidence of plasmids in bacteria isolated from soil and to investigate the occurrence of metal and antibiotic resistance bacteria, and consequently to select the potential application of these bacteria in bioremediation. The total bacterial count (CFU/gm in site (B was higher than that in site (A. Moreover, the CFU values in summer were higher than those values in winter at both sites. A total of 771 bacterial isolates were characterized as Bacillus, Micrococcus, Staphylococcus, Pseudomonas, Eschershia, Shigella, Xanthomonas, Acetobacter, Citrobacter, Enterobacter, Moraxella and Methylococcus. Minimum inhibitory concentrations (MICs of Pb+2, Cu+2, Zn+2, Hg+2, Co+2, Cd+2, Cr+3, Te+2, As+2 and Ni+2 for plasmid-possessed bacteria were determined and the highest MICs were 1200 µg/mL for lead, 800 µg/mL for both Cobalt and Arsenate, 1200 µg/mL for Nickel, 1000 µg/ml for Copper and less than 600 µg/mL for other metals. Bacterial isolates from both sites A and B showed multiple heavy metal resistance. A total of 337 bacterial isolates contained plasmids and the incidence of plasmids was approximately 25-50% higher in bacteria isolated from site (B than that from site (A. These isolates were resistance to different antibiotics. Approximately, 61% of the bacterial isolates were able to assimilate insecticide, carbaryl, as a sole source of carbon and energy. However, the Citrobacter AA101 showed the best growth on carbaryl.

The drug target genes show higher evolutionary conservation than non-target genes.

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Lv, Wenhua; Xu, Yongdeng; Guo, Yiying; Yu, Ziqi; Feng, Guanglong; Liu, Panpan; Luan, Meiwei; Zhu, Hongjie; Liu, Guiyou; Zhang, Mingming; Lv, Hongchao; Duan, Lian; Shang, Zhenwei; Li, Jin; Jiang, Yongshuai; Zhang, Ruijie

2016-01-26

Although evidence indicates that drug target genes share some common evolutionary features, there have been few studies analyzing evolutionary features of drug targets from an overall level. Therefore, we conducted an analysis which aimed to investigate the evolutionary characteristics of drug target genes. We compared the evolutionary conservation between human drug target genes and non-target genes by combining both the evolutionary features and network topological properties in human protein-protein interaction network. The evolution rate, conservation score and the percentage of orthologous genes of 21 species were included in our study. Meanwhile, four topological features including the average shortest path length, betweenness centrality, clustering coefficient and degree were considered for comparison analysis. Then we got four results as following: compared with non-drug target genes, 1) drug target genes had lower evolutionary rates; 2) drug target genes had higher conservation scores; 3) drug target genes had higher percentages of orthologous genes and 4) drug target genes had a tighter network structure including higher degrees, betweenness centrality, clustering coefficients and lower average shortest path lengths. These results demonstrate that drug target genes are more evolutionarily conserved than non-drug target genes. We hope that our study will provide valuable information for other researchers who are interested in evolutionary conservation of drug targets.

Higher antibiotic yielding mutants of bacillus subtilis by gamma radiation

International Nuclear Information System (INIS)

Ahmad, M.S.; Shaukat, G.A.; Malik, M.A.

1987-01-01

When Bacillus Subtilis AECL69 was grown in malt extract-pepetone-molasses-sugar (MPMS) medium, it could produce antibiotic substance(s) with antibacterial and antifungal properties in the culture fluid. The bacterial cells grown in MPMS medium were washed and suspended into distilled water and irradiated with gamma rays in Gammacell 220 at different doses. Higher antibiotic yielding isolates (plus mutants) were obtained from cell pollutions irradiated at 15 Kr. These gamma rays-induced plus mutants showed simultaneous higher production of antibacterial as well as antifungal activity. (author)

Antimicrobial Effect of Bacteriocin produced Pediococcus pentosaceus on some clinical isolates

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Nehad A. Taher

2017-07-01

Full Text Available About 10 isolates of Pediococcus sp were isolated from different cheese made in Iraq, These isolates were identified morphologically and biochemically and Api20 kit, thus there was only 6 isolate were identified as Pediococcus pentosaceus (60%.In this study, we investigate, the effect of crude Bacteriocin from Pediococcus pentosaceus on 30 clinical isolates (5 E.coli, 5 Klepsiella pneumoniae, 5 Staphylococcus aureus, 5 Pseudomonas aeroginosa, 5 Bacillus subtilis, 5 Candida albicans. The protein concentration of this Bacteriocin was measured 67mg\\ml by Bradford method and used as (1:2 by vol during the measuring the antimicrobial activity against the above clinical isolates by two methods wells and  agar plug assay. The results showed that  the inhibitory activity of this Bacteriocin was higher by wells method than agar pluq assay against Gram–positive bacteria or Gram-negative bacteria and yeast under this study.

Molecular Characterization of Geographically Different Banana bunchy top virus Isolates in India.

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Selvarajan, R; Mary Sheeba, M; Balasubramanian, V; Rajmohan, R; Dhevi, N Lakshmi; Sasireka, T

2010-10-01

Banana bunchy top disease (BBTD) caused by Banana bunchy top virus (BBTV) is one of the most devastating diseases of banana and poses a serious threat for cultivars like Hill Banana (Syn: Virupakshi) and Grand Naine in India. In this study, we have cloned and sequenced the complete genome comprised of six DNA components of BBTV infecting Hill Banana grown in lower Pulney hills, Tamil Nadu State, India. The complete genome sequence of this hill banana isolate showed high degree of similarity with the corresponding sequences of BBTV isolates originating from Lucknow, Uttar Pradesh State, India, and from Fiji, Egypt, Pakistan, and Australia. In addition, sixteen coat protein (CP) and thirteen replicase genes (Rep) sequences of BBTV isolates collected from different banana growing states of India were cloned and sequenced. The replicase sequences of 13 isolates showed high degree of similarity with that of South Pacific group of BBTV isolates. However, the CP gene of BBTV isolates from Shervroy and Kodaikanal hills of Tamil Nadu showed higher amino acid sequence variability compared to other isolates. Another hill banana isolate from Meghalaya state had 23 nucleotide substitutions in the CP gene but the amino acid sequence was conserved. This is the first report of the characterization of a complete genome of BBTV occurring in the high altitudes of India. Our study revealed that the Indian BBTV isolates with distinct geographical origins belongs to the South Pacific group, except Shervroy and Kodaikanal hill isolates which neither belong to the South Pacific nor the Asian group.

Characterization of Staphylococcus aureus isolates from raw milk sources in Victoria, Australia.

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McMillan, Kate; Moore, Sean C; McAuley, Catherine M; Fegan, Narelle; Fox, Edward M

2016-07-29

Highly pathogenic strains of Staphylococcus aureus can cause disease in both humans and animals. In animal species, including ruminants, S. aureus may cause severe or sub-clinical mastitis. Dairy animals with mastitis frequently shed S. aureus into the milk supply which can lead to food poisoning in humans. The aim of this study was to use genotypic and immunological methods to characterize S. aureus isolates from milk-related samples collected from 7 dairy farms across Victoria. A total of 30 S. aureus isolates were collected from milk and milk filter samples from 3 bovine, 3 caprine and 1 ovine dairy farms across Victoria, Australia. Pulsed Field Gel Electrophoresis (PFGE) identified 11 distinct pulsotypes among isolates; all caprine and ovine isolates shared greater than 80 % similarity regardless of source. Conversely, bovine isolates showed higher diversity. Multi-Locus Sequence Typing (MLST) identified 5 different sequence types (STs) among bovine isolates, associated with human or ruminant lineages. All caprine and ovine isolates were ST133, or a single allele variant of ST133. Two new novel STs were identified among isolates in this study (ST3183 and ST3184). With the exception of these 2 new STs, eBURST analysis predicted all other STs to be founding members of their associated clonal complexes (CCs). Analysis of genetic markers revealed a diverse range of classical staphylococcal enterotoxins (SE) among isolates, with 11 different SEs identified among bovine isolates, compared with just 2 among caprine and ovine isolates. None of the isolates contained mecA, or were resistant to oxacillin. The only antibiotic resistance identified was that of a single isolate resistant to penicillin; this isolate also contained the penicillin resistance gene blaZ. Production of SE was observed at 16 °C and/or 37 °C in milk, however no SE production was detected at 12 °C. Although this study characterized a limited number of isolates, bovine-associated isolates

Isolation and identification of halotolerant soil bacteria from coastal Patenga area.

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Rahman, Shafkat Shamim; Siddique, Romana; Tabassum, Nafisa

2017-10-30

Halotolerant bacteria have multiple uses viz. fermentation with lesser sterility control and industrial production of bioplastics. Moreover, it may increase the crop productivity of coastal saline lands in Bangladesh by transferring the salt tolerant genes into the plants. The study focused on the isolation and identification of the halotolerant bacteria from three soil samples, collected from coastal Patenga area. The samples were inoculated in nutrient media containing a wide range of salt concentrations. All the samples showed 2, 4 and 6% (w/v) salt tolerance. The isolates from Patenga soil (4, 6%) and beach soil (2%) showed catalase activity and all the isolates showed negative results for oxidase activity, indole production, lactose and motility. All the samples provided positive results for dextrose fermentation. Other tests provided mixed results. Based on the morphological characteristics, biochemical tests and ABIS software analysis the isolates fall within the Enterobacteriaceae, Clostridium and Corynebacterium, with a predominance of Vibrios. Overall the isolates can be considered as mild halotolerant, with the best growth observed at lower salinities and no halophilism detected. Among many possibilities, the genes responsible for the salt tolerant trait in these species can be identified, extracted and inserted into the crop plants to form a transgenic plant to result in higher yield for the rest of the year.

Numerical conversion efficiency of thermally isolated Seebeck nanoantennas

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Edgar Briones

2016-11-01

Full Text Available In this letter, we evaluate the conversion efficiency of thermally isolated Seebeck nanoantennas by numerical simulations and discuss their uses and scope for energy harvesting applications. This analysis includes the simple case of titanium-nickel dipoles suspended in air above the substrate by a 200 nm silicon dioxide membrane to isolate the heat dissipation. Results show that substantially thermal gradients are induced along the devices leading to a harvesting efficiency around 10-4 %, 400 % higher than the previously reported Seebeck nanoantennas. In the light of these results, different optimizing strategies should be considered in order to make the Seebeck nanoantennas useful for harvesting applications.

Characterization of Candidate probionts isolated from human breast milk.

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Khalkhali, S; Mojgani, N

2017-05-20

This study was designed to isolate and identify the potential probionts present in 32 healthy mothers' breast milk. Microbial culture media and 16SrRNA sequencing were used to isolate and identify the bacteria and all isolates were analyzed for their antagonistic potential, resistance to acidic pH, bile salts and survival under simulated gastric and intestinal conditions. The colonization potential was further assessed based on adherence to human enterocyte-like Caco-2 cell lines. The breast milk samples harbored significant numbers of Gram positive and catalase negative (85%) bacteria. Based on 16SrRNA sequencing, these isolates were identified as Lactobacillus casei, L.gasseri, L.fermentum, L.plantarum, Pediococcus acidilactici, and Enterococcus facieum. Among the isolates, P. acidilactici was the most frequent species (71%) present in these samples. Few Gram and catalase positive isolates, Staphylococcus aureus and S.hominiis were also observed. The isolates were viable and unviable in pH 3 and 1.5, respectively, while all isolates survived in 1.0% bile salt. As putative probionts, P.acidilactici 1C showed a significantly higher percentage of adhesion to Caco-2 cells (p< 0.05)than the other two isolates L.plantarum 7A and E.facieum 2C. Bacterial strains isolated from human breast milk were shown to have probiotic properties including anti-infective protection and may be considered as future therapeutics for infants.

The heterogeneity of socially isolated older adults: a social isolation typology.

Science.gov (United States)

Machielse, Anja

2015-01-01

Recent statistics show a growing number of older adults who are living alone and are socially isolated. It is against this background that, in recent years, many interventions have been developed to address social isolation among the elderly. Evaluative studies show that most interventions are hardly effective, though. An important reason for this is the heterogeneity of the socially isolated. This article offers insight into this heterogeneity by presenting a typology with different profiles of socially isolated older adults and the intervention implications of this typology. The typology is derived from an extensive qualitative study on socially isolated elderly individuals in the Netherlands. The typology imposes some degree of order to a diversity of circumstances, ambitions, and possibilities of the socially isolated elderly, thereby deepening the understanding of the heterogeneity of this population. The definition of social isolation used in this study starts from a societal angle of incidence, namely the current policy context of Western European welfare states, in which governments emphasize the importance of independence and self-reliance of their citizens. Developed from that perspective, the typology provides a theoretical basis for applying interventions aimed at increasing self-reliance of social isolated elderly. This perspective on social isolation also has consequences for the way in which the effectiveness of interventions to alleviate social isolation is assessed.

[Community structure and diversity of culturable moderate halophilic bacteria isolated from Qrhan salt lake on Qinghai-Tibet Plateau].

Science.gov (United States)

Shen, Shuo

2017-04-04

I studied the community structure and diversity of culturable moderate halophilic bacteria isolated from Qrhan Salt Lake. I isolated and cultured the moderate halophilic bacteria on different selective media. After the 16S rRNA gene sequences was amplified and measured, I constructed the phylogenic tree, analyzed the community structure and calculated the diversity indexes according to the 16S rRNA gene information. A total of 421 moderate halophilic bacteria were isolated from water and mud samples in Qrhan Salt Lake. The 16S rRNA gene information showed that 4 potential novel species belonged to the family Bacillaceae. Eighty-three model strains belonged to 3 phylurms 6 families 16 genus. Among them, Bacillus sp., Oceanobacillus sp. and Halomonas sp. were dominant species. Diversity analysis showed that the diversity of strains isolated from water sample was higher than that from mud sample, but the dominance degree of strains isolated from mud sample was higher than that from water sample. The genetic diversity of moderate halophilic bacteria isolated from Qrhan Salt Lake was abundant. Also, there were dominant and novel species of culturable moderate halophilic bacteria in this lake.

Transcription of the var genes from a freshly-obtained field isolate of Plasmodium falciparum shows more variable switching patterns than long laboratory-adapted isolates.

Science.gov (United States)

Ye, Run; Zhang, Dongmei; Chen, Biaobang; Zhu, Yongqiang; Zhang, Yilong; Wang, Shengyue; Pan, Weiqing

2015-02-07

Antigenic variation in Plasmodium falciparum involves switching among multicopy var gene family and is responsible for immune evasion and the maintenance of chronic infections. Current understanding of var gene expression and switching patterns comes from experiments conducted on long laboratory-adapted strains, with little known about their wild counterparts. Genome sequencing was used to obtain 50 var genes from a parasite isolated from the China-Myanmar border. Four clones with different dominant var genes were cultured in vitro in replicates for 50 generations. Transcription of the individual var gene was detected by real-time PCR and then the switching process was analysed. The expression of multicopy var genes is mutually exclusive in clones of a wild P. falciparum isolate. The activation of distinct primary dominant var genes leads to different and favoured switching patterns in the four clones. The on/off rates of individual var genes are variable and the choice of subsequent dominant var genes are random, which results in the different switching patterns among replicates of each clonal wild P. falciparum isolate with near identical initial transcription profiles. This study suggests that the switching patterns of var genes are abundant, which consist of both conserved and random parts.

Volatile organic compounds emitted by filamentous fungi isolated from flooded homes after Hurricane Sandy show toxicity in a Drosophila bioassay.

Science.gov (United States)

Zhao, G; Yin, G; Inamdar, A A; Luo, J; Zhang, N; Yang, I; Buckley, B; Bennett, J W

2017-05-01

Superstorm Sandy provided an opportunity to study filamentous fungi (molds) associated with winter storm damage. We collected 36 morphologically distinct fungal isolates from flooded buildings. By combining traditional morphological and cultural characters with an analysis of ITS sequences (the fungal DNA barcode), we identified 24 fungal species that belong to eight genera: Penicillium (11 species), Fusarium (four species), Aspergillus (three species), Trichoderma (two species), and one species each of Metarhizium, Mucor, Pestalotiopsis, and Umbelopsis. Then, we used a Drosophila larval assay to assess possible toxicity of volatile organic compounds (VOCs) emitted by these molds. When cultured in a shared atmosphere with growing cultures of molds isolated after Hurricane Sandy, larval toxicity ranged from 15 to 80%. VOCs from Aspergillus niger 129B were the most toxic yielding 80% mortality to Drosophila after 12 days. The VOCs from Trichoderma longibrachiatum 117, Mucor racemosus 138a, and Metarhizium anisopliae 124 were relatively non-toxigenic. A preliminary analysis of VOCs was conducted using solid-phase microextraction-gas chromatography-mass spectrometry from two of the most toxic, two of the least toxic, and two species of intermediate toxicity. The more toxic molds produced higher concentrations of 1-octen-3-ol, 3-octanone, 3-octanol, 2-octen-1-ol, and 2-nonanone; while the less toxic molds produced more 3-methyl-1-butanol and 2-methyl-1-propanol, or an overall lower amount of volatiles. Our data support the hypothesis that at certain concentrations, some VOCs emitted by indoor molds are toxigenic. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Bioremediation Of Heavy Metals By Pseudomonas Putida Isolated From Groundwater In Egypt.

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Fawazy

2015-08-01

Full Text Available In this present study total four bacterial isolates were obtained from 34 collected groundwater samples in 10th of Ramadan Sharkia governorate Egypt. These isolate were grown on nutrient agar supplemented with 1mgl of iron manganese and combination between them VV. Further testing of the bacterial isolates were grown on nutrient agar supplemented with different concentrations 2 4 5 6 7 8 and 9 mgl of iron and manganese. Out of four isolates one bacterial isolate no.83 has shown the resistance to heavy metals at maximum concentration of 8mgl. Selected isolate no.S83 was identified as Pseudomonas putida S83 according to Bergeys manual depending on morphological and biochemical characteristics. Transmission electron microscopy study of P. putida isolate no. S83 showed accumulation of heavy metal salts within and external to bacterial cells. P. putida S83 have higher removal efficiency of Fe2 94.5 and Mn2 94 at concentration 2 mgl and 96 hours.

A urine midmolecule osteocalcin assay shows higher discriminatory power than a serum midmolecule osteocalcin assay during short-term alendronate treatment of osteoporotic patients.

Science.gov (United States)

Srivastava, A K; Mohan, S; Singer, F R; Baylink, D J

2002-07-01

We isolated and characterized a peptide fragment corresponding to amino acid sequence 14-28 of human osteocalcin in urine from Paget's disease, and developed a polyclonal antibody reactive to this peptide in urine. We used this antibody to measure urinary fragments of osteocalcin and compared to efficacy of the urinary osteocalcin assay with a serum osteocalcin (sOC) assay (ELISA-Osteo, Cis-Bio International) to monitor the short-term changes in bone turnover in response to alendronate treatment. The synthetic peptide-based urinary osteocalcin (uOC) radioimmunoassay (RIA) showed an analytical sensitivity of 6.25 ng/mL, standard curve range of 3.12-400 ng/mL, and mean intra- (n = 20) and interassay (n = 30) coefficient of variation (CV) of sALP) (Alkphose-B, Metra Biosystems) in serum samples. The percent change data obtained between baseline and 30 days (n = 18) posttreatment suggested a rapid decline in uOC concentration (-27%, p sALP (-3.4%, p = 0.689), two specific markers of bone formation. As expected, due to the coupling of bone formation and bone resorption, the concentration of all markers showed a 30%-45% decline compared with baseline values after 90 days (n = 16) of treatment. Correlation of markers after a 30 day treatment with alendronate revealed a higher correlation (r = 0.61, p sALP (r = -0.14, p = 0.295) with uNTx. Similarly, correlation coefficients with r values between 0.48 and 0.55 (p < 0.05) were observed between uOC, sNTx, and sCTx, whereas no significant correlation was observed between sOC and sNTx or sCTx. These results provide indirect evidence that fragments measured by the urine assay probably originated from bone resorption, and suggest that the uOC assay could be used to assess short-term changes in bone metabolism with regard to osteocalcin.

Extraordinary Diversity of Immune Response Proteins among Sea Urchins: Nickel-Isolated Sp185/333 Proteins Show Broad Variations in Size and Charge

Science.gov (United States)

Sherman, Lauren S.; Schrankel, Catherine S.; Brown, Kristy J.; Smith, L. Courtney

2015-01-01

Effective protection against pathogens requires the host to produce a wide range of immune effector proteins. The Sp185/333 gene family, which is expressed by the California purple sea urchin Strongylocentrotus purpuratus in response to bacterial infection, encodes a highly diverse repertoire of anti-pathogen proteins. A subset of these proteins can be isolated by affinity to metal ions based on multiple histidines, resulting in one to four bands of unique molecular weight on standard Western blots, which vary depending on the individual sea urchin. Two dimensional gel electrophoresis (2DE) of nickel-isolated protein samples followed by Western blot was employed to detect nickel-isolated Sp185/333 (Ni-Sp185/333) proteins and to evaluate protein diversity in animals before and after immune challenge with marine bacteria. Ni-Sp185/333 proteins of the same molecular weight on standard Western blots appear as a broad complex of variants that differ in pI on 2DE Western blots. The Ni-Sp185/333 protein repertoire is variable among animals, and shows a variety of changes among individual sea urchins in response to immune challenges with both the same and different species of bacteria. The extraordinary diversity of the Ni-Sp185/333 proteins may provide significant anti-pathogen capabilities for sea urchins that survive solely on innate immunity. PMID:26406912

Wideband Isolation by Frequency Conversion in a Josephson-Junction Transmission Line

Science.gov (United States)

Ranzani, Leonardo; Kotler, Shlomi; Sirois, Adam J.; DeFeo, Michael P.; Castellanos-Beltran, Manuel; Cicak, Katarina; Vale, Leila R.; Aumentado, José

2017-11-01

Nonreciprocal transmission and isolation at microwave frequencies are important in many practical applications. In particular, compact isolators are useful in protecting sensitive quantum circuits operating at cryogenic temperatures from amplifier backaction and other environmental noise such as black-body radiation from higher temperature stages. However, the size of commercial cryogenic isolators limits the ability to measure multiple quantum circuits because of space constraints in typical dilution refrigerator systems. Furthermore, isolators usually require the use of ferrite components that cannot be integrated at the chip level and, since they also need large biasing magnetic fields, are incompatible with superconducting quantum circuits. In this work we show one way to accomplish isolation in a superconducting chip-scale device, a traveling-wave unidirectional frequency converter based on a parametrically pumped superconducting Josephson-junction transmission line, demonstrating better than 4.8 dB of inferred signal isolation from 6.6 to 11.4 GHz, with a maximum of 12 dB at 9.5 GHz. By using frequency diplexing techniques a conventional isolator could be implemented over this bandwidth.

Effect of Origanum heracleoticum L. essential oil on food-borne Penicillium aurantiogriseum and Penicilium chrysogenum isolates

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Čabarkapa Ivana S.

2011-01-01

Full Text Available Molds are ubiquitously distributed in nature and their spores can be found in the atmosphere even at high altitudes. The difficulty of controlling these undesirable molds, as well as the growing interest of the consumers in natural products, have been forcing the industry to find new alternatives for food preservation. The modern trends in nutrition suggest the limitation of synthetic food additives or substitution with natural ones. Aromatic herbs are probably the most important source of natural antimicrobial agents. Origanum heracleoticum L. essential oil has been known as an interesting source of antimicrobial compounds to be applied in food preservation. In the this work, we have investigated the effect of essential oil obtained from O. heracleoticum on growth of six isolates of Penicillium aurantiogriseum and four isolates of Penicillium chrysogenum isolated from meat plant for traditional Petrovacka sausage (Petrovská klobása production. The findings reveal that the essential oil of O. heracleoticum provides inhibition of all of fungal isolates tested. O. heracleoticum L. essential oil exhibited higher antifungal activity against the isolates of P. chrysogenum than the isolates of P. aurantiogriseum. O. heracleoticum essential oil showed a MIC value ranging from 25 to 100 μL/mL. The fungi cultivated in the medium with higher concentration of essential oil showed certain morphological changes. The alterations included lack of sporulation and loss of pigmentation.

Input-output rearrangement of isolated converters

DEFF Research Database (Denmark)

Madsen, Mickey Pierre; Kovacevic, Milovan; Mønster, Jakob Døllner

2015-01-01

This paper presents a new way of rearranging the input and output of isolated converters. The new arrangement posses several advantages, as increased voltage range, higher power handling capabilities, reduced voltage stress and improved efficiency, for applications where galvanic isolation...

A Geographically Diverse Collection of Schizosaccharomyces pombe Isolates Shows Limited Phenotypic Variation but Extensive Karyotypic Diversity

NARCIS (Netherlands)

Brown, William R A; Liti, Gianni; Rosa, Carlos; James, Steve; Roberts, Ian; Robert, Vincent; Jolly, Neil; Tang, Wen; Baumann, Peter; Green, Carter; Schlegel, Kristina; Young, Jonathan; Hirchaud, Fabienne; Leek, Spencer; Thomas, Geraint; Blomberg, Anders; Warringer, Jonas

2011-01-01

The fission yeast Schizosaccharomyces pombe has been widely used to study eukaryotic cell biology, but almost all of this work has used derivatives of a single strain. We have studied 81 independent natural isolates and 3 designated laboratory strains of Schizosaccharomyces pombe.

Oligotrophic bacteria isolated from clinical materials.

OpenAIRE

Tada, Y; Ihmori, M; Yamaguchi, J

1995-01-01

Oligotrophic bacteria (oligotrophs) are microorganisms that grow in extremely nutritionally deficient conditions in which the concentrations of organic substances are low. Many oligotrophic bacteria were isolated from clinical materials including urine, sputum, swabbings of the throat, vaginal discharges, and others. Seventy-seven strains of oligotrophic bacteria from 871 samples of clinical material were isolated. A relatively higher frequency of isolation of oligotrophic bacteria was shown ...

Hydrogels from feather keratin show higher viscoelastic properties and cell proliferation than those from hair and wool keratins.

Science.gov (United States)

Esparza, Yussef; Bandara, Nandika; Ullah, Aman; Wu, Jianping

2018-09-01

Hydrogel prepared from keratin shows potential applications in tissue engineering. However, the importance of the keratin sources has not been considered. The objectives of this study were to characterize and compare the rheological (storage modulus), physical (porosity, pore size, swelling capacity, and water contact angle) and in vitro cell compatibility of hydrogel scaffolds prepared from various keratin sources. Keratins were characterized by means of their molecular weight, amino acid composition, thermal and conformational properties. Hydrogels from chicken feather keratins demonstrated substantially higher storage modulus (G') than hair and wool keratin hydrogels. However, higher swelling capacity (>3000%) was determined in hair and wool over feather keratin (1500%) hydrogels. Our results suggest that small molecular weight and β-sheet conformation of feather keratin (~10 kDa) facilitated the self-assembly of rigid hydrogels through disulfide bond re-oxidation. Whereas, high molecular weight (10-75 kDa) stretchable α-helix conformation in hair and wool keratins resulted in weaker hydrogels. The cell cultures using fibroblasts showed the highest proliferation rate on chicken feather keratin hydrogel scaffolds. After 15 days of culture, partial breakdown of keratin fibers was observed. Results indicate that stiffer avian keratins can be used to fabricate more mechanically robust biomaterials than mammalian keratins. Copyright © 2018 Elsevier B.V. All rights reserved.

Conjunctival sac bacterial flora isolated prior to cataract surgery

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Suto C

2012-01-01

a history of allergic conjunctivitis. Methicillin-resistant coagulase-negative staphylococci showed a significantly higher detection rate in diabetic patients than nondiabetic patients (20.3% versus 7.0%, P < 0.05. The percentage of all isolates resistant to levofloxacin, cefmenoxime, and tobramycin was 14.0%, 15.2%, and 17.9%, respectively, with no significant differences among these drugs.Conclusion: The high bacterial isolation rate in patients >60 years old and the high methicillin-resistant coagulase-negative staphylococci isolation rate in patients with diabetes are important to consider for prevention of perioperative infections.Keywords: endophthalmitis, cataract surgery, conjunctival sac, bacterial flora, diabetes mellitus

In Vitro Activities of Amphotericin B, Terbinafine, and Azole Drugs against Clinical and Environmental Isolates of Aspergillus terreus Sensu Stricto

Science.gov (United States)

Fernández, Mariana S.; Rojas, Florencia D.; Cattana, María E.; Sosa, María de los Ángeles; Iovannitti, Cristina A.; Giusiano, Gustavo E.

2015-01-01

The antifungal susceptibilities of 40 clinical and environmental isolates of A. terreus sensu stricto to amphotericin B, terbinafine, itraconazole, and voriconazole were determined in accordance with CLSI document M38-A2. All isolates had itraconazole and voriconazole MICs lower than epidemiologic cutoff values, and 5% of the isolates had amphotericin B MICs higher than epidemiologic cutoff values. Terbinafine showed the lowest MICs. No significant differences were found when MICs of clinical and environmental isolates were compared. PMID:25824228

VEGETATIVE COMPATIBILITY OF Fusarium oxysporum ISOLATED FROM WEEDS IN EASTERN CROATIA

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Jelena Ilić

2013-06-01

Full Text Available Different formae speciales of Fusarium oxysporum are the main causal agent of Fusarium wilts. In 2008 and 2009 we collected F. oxysporum samples from symptomless Abutilon theophrasti, Xanthium strumarium, Chenopodium album, Matricaria perforata, Ambrosia artemisiifolia, Polygonum lapathifolium, Sonchus arvensis, Amaranthus blitoides, Amaranthus retroflexus, Datura stramonium, Sorghum halepense and Hibiscus trionum. Only 16 out of 41 isolates of F. oxysporum yielded nit mutants. The frequency of nit3 mutants was higher (43% than the frequency of nit1 (35% and NitM (22% mutants. Two vegetative compatibility groups (VCGs of F. oxysporum were determined in the complementation tests. These results stress out the problem with isolation of nit mutants and show a high genetic diversity of F. oxysporum isolated from weeds.

Social isolation and risk for malnutrition among older people.

Science.gov (United States)

Boulos, Christa; Salameh, Pascale; Barberger-Gateau, Pascale

2017-02-01

Social isolation and loneliness are emerging issues among the geriatric population. The relationships between both, and their impact on health and nutritional status in older people are complex. The purpose of the present study was to evaluate the association between three components of social isolation: social network, feeling of loneliness, commensality and nutritional status. A total of 1200 randomly selected elderly individuals aged ≥65 years and living in rural areas of Lebanon participated in the present study. Data were collected during a face-to-face interview including nutritional status (Mini-Nutritional Assessment), measures of social isolation (Lubben Social Network Scale), subjective loneliness (Jong-Gierveld Loneliness Scale), sociodemographic conditions, and health and functional status. Both social isolation and loneliness were independently associated with a higher risk of malnutrition (OR 1.58, P = 0.011; OR 1.15, P = 0.020, respectively). However no association was found between the frequency of sharing meals and the risk of malnutrition. The present study showed that social isolation and subjective loneliness are two independent risk factors for malnutrition among older people. Geriatr Gerontol Int 2017; 17: 286-294. © 2016 Japan Geriatrics Society.

Effect of Fusarium isolates and their filtrates on respiratory rate and chemical analysis of squash plants.

Science.gov (United States)

El-Shenawy, Z; Mansour, M A; El-Behrawi, S

1978-01-01

The highly pathogenic isolate stimulated the emergence of the squash seedlings first, caused, however, the highest death rate of the seedlings finally. Fusarium isolates and their culture filtrates inhibited the respiratory rate of squash plants significantly. However, F. oxysporum isolates inhibited respiration more than F. solani isolates. Seasonal changes of respiration decline show that the respiratory rate decreased with plant growth in the case of infested soil and of plants injected with culture filtrates. However, spraying Fusarium culture filtrates on the foliage gave opposite results when the plants grew older. Fusarium solani isolates decreased nitrogen content of squash stems and leaves, while F. oxysporum isolates gave reverse results. Injecting Fusarium culture filtrate into the plant decreased nitrogen content of both stems and leaves, while spraying the foliage with the filtrates increased nitrogen content more than that of the control. Phosphorus content of the stems of squash plants, sown in infested soil, was less than in the control when the plants were treated with F. solani and higher when they were treated with F. oxysporum isolates. On the other hand, the phosphorus content of squash leaves was higher than in the control. In the case of injected plants, however, the phosphorus content in stems and leaves was equal to that of the control or less, and with sprayed plants it was higher than in the control. Infesting the soil with Fusarium isolates and spraying the foliage with their culture filtrates increased potassium content of squash stems and leaves, while injecting the filtrates into the plants decreased potassium content of both stems and leaves.

Sensitivity studies of a seismically isolated system to low frequency amplification

International Nuclear Information System (INIS)

Wu, T.S.; Seidensticker, R.W.

1987-06-01

Responses of a seismically isolated structure to earthquake motions will depend primarily on the input ground motion and the isolation system frequency. The isolation frequency generally is relatively low when isolating against horizontal ground motions. After installation, the isolation frequency could deviate from its designed value due to aging, manufacturing tolerance etc. In addition, under cettain soil conditions, the input motion could have high energy content at relatively low frequencies. This report covers the first of these two concerns by performing a sensitivity study of the variations in isolation frequency on the responses of a nuclear reactor module incorporated with an isolation system. Results from a number of ground motions have shown that, for most earthquake motions, a higher isolation frequency tends to yield higher maximum acceleration, higher transmitted shear force, and lower relative displacement between the isolated and unisolated parts of the structure. In one of the ground motions considered, a 7% increase in the isolation frequency from its original design value is observed to give over a 22% increase in the transmitted shear force. Other ground motions, especially those exhibiting sharp rise in spectral accelerations in the vicinity of the designed isolated frequency, yield responses following the same general trend

Screening of Lactic Acid Bacteria Isolated from Iranian sourdoughs for Antifungal Activity: Enterococcus faecium showed the Most Potent Antifungal Activity in Bread

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Alam Taghi-Zadeh

2017-09-01

Full Text Available Background and Objective: The use of antifungal lactic acid bacteria as starter for bread making could be a good alternative to improve the stability of bread shelf life.Material and Methods: In this study, a total of 57 lactic acid bacteria were isolated from spontaneously fermented wheat sourdoughs collected in Chahar-Mahalo Bakhryari province of Iran. The isolates were screened for in vitro antifungal activity (towards Aspergilus niger or Penicillium roqueforti; and the selected isolates (six isolates were applied in flat bread making. The freshly baked breads were nebulized with a suspension of either molds, containing 104 spores ml-1, and the fungal growth on breads was monitored over a 7-day storage period.Results and Conclusion: Bread produced with either isolates AN3 and MB1 (both were identified as Enterococcus faecium restrained the growth of Aspergillus niger for up to 5 days. Even though none of the isolates were strong enough to inhibit the growth of Penicillium roquforti on bread, the surface area of breads contaminated by this fungus was significantly lower than the control samples. To our knowledge, it was the first report indicating the anti-mold activity of Enterococcus faecium strains isolated from sourdough. These isolates seem to be promising for further analysis and their application in bread industry for prolonging the shelf life.Conflict of interest: The authors declare that there is no conflict of interest.

[Isolation and antimicrobial activities of actinomycetes from vermicompost].

Science.gov (United States)

Wang, Xue-jun; Yan, Shuang-lin; Min, Chang-li; Yang, Yan

2015-02-01

In this paper, actinomycetes were isolated from vermicompost by tablet coating method. Antimicrobial activities of actinomycetes were measured by the agar block method. Strains with high activity were identified based on morphology and biochemical characteristics, as well as 16S rDNA gene sequence analysis. The results showed that 26 strains of actinomycetes were isolated, 16 of them had antimicrobial activities to the test strains which accounts for 61.54% of all strains. Among the 16 strains, the strain QYF12 and QYF22 had higher antimicrobial activity to Micrococcus luteus, with a formed inhibition zone of 27 mm and 31 mm, respectively. While the strain QYF26 had higher antimicrobial activity to Bacillus subtilis, and the inhibition zone diameter was 21 mm. Based on the identification of strains with high activity, the strain QYF12 was identified as Streptomyces chartreusis, the strain QYF22 was S. ossamyceticus and the strain QYF26 was S. gancidicus. This study provided a theoretical basis for further separate antibacterial product used for biological control.

Research on typical topologies of a tubular horizontal-gap passive magnetic levitation vibration isolator

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Zhou Yiheng

2017-01-01

Full Text Available Magnetic levitation vibration isolators have attracted more and more attention in the field of high-precision measuring and machining equipment. In this paper, we describe a tubular horizontal-gap passive magnetic levitation vibration isolator. Four typical topologies of the tubular horizontal-gap passive magnetic levitation vibration isolator are proposed. The analytical expression of magnetic force is derived. The relationship between levitation force, force density, force ripple and major structural parameters are analysed by finite element method, which is conductive to the design and optimization of the tubular horizontal-gap passive magnetic levitation vibration isolator. The force characteristics of different topologies of the tubular horizontal-gap passive magnetic levitation vibration isolator are compared and evaluated from the aspect of force density, force ripple and manufacturability. In comparison with conventional passive magnetic levitation vibration isolators, the proposed tubular horizontal-gap passive magnetic levitation vibration isolator shows advantage in higher force density.

Isolated Proofs of Knowledge and Isolated Zero Knowledge

DEFF Research Database (Denmark)

Damgård, Ivan Bjerre; Nielsen, Jesper Buus; Wichs, Daniel

2008-01-01

. This is because the prover may just be forwarding messages between the environment and the verifier while the environment performs all the necessary computation. In this paper we consider an ℓ-isolated prover, which is restricted to exchanging at most ℓ bits of information with its environment. We introduce a new...... notion called ℓ-isolated proofs of knowledge (ℓ-IPoK). These protocols securely ensure that an ℓ-isolated prover knows the witness. To prevent the above-mentioned attack, an ℓ-IPoK protocol has to have communication complexity greater than ℓ. We show that for any relation in NP and any value ℓ...

Development of novel Alicyclobacillus spp. isolation medium.

Science.gov (United States)

Chang, S; Kang, D-H

2005-01-01

To develop a new isolation medium with higher recovery rates of Alicyclobacillus spp. SK agar was developed with optimized incubation temperature, pH, acidulant, Tween 80 concentration and divalent cation addition. Results indicate that detection of Alicyclobacillus spp. by SK agar was significantly higher (P > 0.05) than those obtained by K agar, orange serum agar, and potato dextrose agar. Current media used for Alicyclobacillus spp. isolation still resulted in high numbers of false negative products. The sensitivity of SK agar to Alicyclobacillus spp. allows detection of low numbers of Alicyclobacillus spp. and also provides a more higher isolation results compared with currently used media. SK agar will be useful to the fruit juice industry to obtain more accurate numbers of contaminant Alicyclobacillus spp. With this media, false negative samples can be reduced, and the likelihood of exported products being rejected can be greatly reduced.

Pathogenicity of Bacillus thuringiensis isolated from two species of Acromyrmex (Hymenoptera, Formicidae

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L. M. N. Pinto

Full Text Available The control of Acromyrmex leaf-cutting ants is necessary due to the severe damage they cause to diverse crops. A possibility was to control them using the bacterium Bacillus thuringiensis (Bt that characteristically produces insecticidal crystal proteins (ICPs. The ICPs have been effective in controlling lepidopterans, dipterans, and coleopterans, but their action against hymenopterans is unknown. This paper describes an attempt to isolate Bt from ants of two Acromyrmex species, to evaluate its pathogenicity towards these ants, and to test isolates by PCR. Bacterial isolates of Bt obtained from A. crassispinus and A. lundi have been assayed against A. lundi in the laboratory. The bioassays were carried out in BOD at 25°C, with a 12-hour photoperiod, until the seventh day after treatment. The Bt isolates obtained were submitted to total DNA extraction and tested by PCR with primers specific to cry genes. The results showed Bt presence in 40% of the assessed samples. The data from the in vivo assays showed a mortality rate higher than 50% in the target population, with the Bt HA48 isolate causing 100% of corrected mortality. The PCR results of Bt isolates showed a magnification of DNA fragments relative to cry1 genes in 22% of the isolates, and cry9 in 67%. Cry2, cry3, cry7, and cry8 genes were not detected in the tested samples, and 22% had no magnified DNA fragments corresponding to the assessed cry genes. The results are promising not only regarding allele identification in new isolates, but also fort the assays aimed at determining the Bt HA48 LC50's, which can eventually be applied in controlling of Acromyrmex leaf-cutting ants.

Experimental Study of Vibration Isolation Characteristics of a Geometric Anti-Spring Isolator

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Lixun Yan

2017-07-01

Full Text Available In order to realize low-frequency vibration isolation, a novel geometric anti-spring isolator consisting of several cantilever blade springs are developed in this paper. The optimal design parameters of the geometric anti-spring isolator for different nonlinear geometric parameters are theoretically obtained. The transmissibility characteristic of the geometric anti-spring isolator is investigated through mathematical simulation. A geometric anti-spring isolator with a nonlinear geometric parameter of 0.92 is designed and its vibration isolation performance and nonlinearity characteristic is experimentally studied. The experiment results show that the designed isolator has good low-frequency vibration isolation performance, of which the initial isolation frequency is less than 3.6 Hz when the load weight is 21 kg. The jump phenomena of the response of the isolator under linear frequency sweep excitation are observed, and this result demonstrates that the geometric anti-spring isolator has a complex nonlinearity characteristics with the increment of excitation amplitude. This research work provides a theoretical and experimental basis for the application of the nonlinear geometric anti-spring low-frequency passive vibration isolation technology in engineering practice.

Plasmodium falciparum isolates from Angola show the StctVMNT haplotype in the pfcrt gene

Science.gov (United States)

2010-01-01

Background Effective treatment remains a mainstay of malaria control, but it is unfortunately strongly compromised by drug resistance, particularly in Plasmodium falciparum, the most important human malaria parasite. Although P. falciparum chemoresistance is well recognized all over the world, limited data are available on the distribution and prevalence of pfcrt and pfmdr1 haplotypes that mediate resistance to commonly used drugs and that show distinct geographic differences. Methods Plasmodium falciparum-infected blood samples collected in 2007 at four municipalities of Luanda, Angola, were genotyped using PCR and direct DNA sequencing. Single nucleotide polymorphisms in the P. falciparum pfcrt and pfmdr1 genes were assessed and haplotype prevalences were determined. Results and Discussion The most prevalent pfcrt haplotype was StctVMNT (representing amino acids at codons 72-76). This result was unexpected, since the StctVMNT haplotype has previously been seen mainly in parasites from South America and India. The CVIET, CVMNT and CVINT drug-resistance haplotypes were also found, and one previously undescribed haplotype (CVMDT) was detected. Regarding pfmdr1, the most prevalent haplotype was YEYSNVD (representing amino acids at codons 86, 130, 184, 1034, 1042, 1109 and 1246). Wild haplotypes for pfcrt and pfmdr1 were uncommon; 3% of field isolates harbored wild type pfcrt (CVMNK), whereas 21% had wild type pfmdr1 (NEYSNVD). The observed predominance of the StctVMNT haplotype in Angola could be a result of frequent travel between Brazil and Angola citizens in the context of selective pressure of heavy CQ use. Conclusions The high prevalence of the pfcrt SVMNT haplotype and the pfmdr1 86Y mutation confirm high-level chloroquine resistance and might suggest reduced efficacy of amodiaquine in Angola. Further studies must be encouraged to examine the in vitro sensitivity of pfcrt SVMNT parasites to artesunate and amodiaquine for better conclusive data. PMID:20565881

MDS shows a higher expression of hTERT and alternative splice variants in unactivated T-cells.

Science.gov (United States)

Dong, Wen; Wu, Lei; Sun, Houfang; Ren, Xiubao; Epling-Burnette, Pearlie K; Yang, Lili

2016-11-01

Telomere instability and telomerase reactivation are believed to play an important role in the development of myelodysplastic syndromes (MDS). Abnormal enzymatic activity of human telomerase reverse transcriptase (hTERT), and its alternative splice variants have been reported to account for deregulated telomerase function in many cancers. In this study, we aim to compare the differences in expression of hTERT and hTERT splice variants, as well as telomere length and telomerase activity in unstimulated T-cells between MDS subgroups and healthy controls. Telomere length in MDS cases was significantly shorter than controls (n = 20, pMDS using World Health Organization classification (WHO subgroups versus control: RARS, p= 0.009; RCMD, p=0.0002; RAEB1/2, p=0.004, respectively) and the International Prognostic Scoring System (IPSS subgroups: Low+Int-1, pMDS patients (n=20) had significantly higher telomerase activity (p=0.002), higher total hTERT mRNA levels (p=0.001) and hTERT α+β- splice variant expression (pMDS (r=0.58, p=0.007). This data is in sharp contrast to data published previously by our group showing a reduction in telomerase and hTERT mRNA in MDS T-cells after activation. In conclusion, this study provides additional insight into hTERT transcript patterns and activity in peripheral T-cells of MDS patients. Additional studies are necessary to better understand the role of this pathway in MDS development and progression.

Thyroid nodules with isolated macrocalcification: Malignancy and diagnostic efficacy of fine-needle aspiration and core needle biopsy

Energy Technology Data Exchange (ETDEWEB)

Na, Dong Gyu; Kim, Dae Sik; Kim, Soo Jin [Dept. of Radiology, Human Medical Imaging and Intervention Center, Seoul (Korea, Republic of); Ryoo, Jae Wook [Dept. of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Jung, So Lyung [Dept. of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

2016-07-15

This study was performed to determine the malignancy risk of thyroid nodules with isolated macrocalcification and to evaluate the diagnostic efficacy of fine-needle aspiration (FNA) and core needle biopsy (CNB). From May 2008 to December 2014, a total of 44 patients with isolated macrocalcifications were enrolled from 4,081 consecutive patients who underwent FNA or CNB at a single institution. We assessed the malignancy risk of nodules with isolated macrocalcification. We compared the diagnostic results between FNA and CNB, and the diagnostic efficacy of each procedure was evaluated by the rate of inconclusive results. We compared the diagnostic performance for malignancy between FNA and CNB with a criterion of malignant or atypia/follicular lesion of undetermined significance (indeterminate) diagnostic results. We investigated whether the ultrasonographic feature of isolated macrocalcification was predictive of malignancy. The malignancy risk of nodules with isolated macrocalcification was 16.1% in 31 nodules with final diagnoses and 11.4% in all nodules. CNB demonstrated a significantly lower rate of nondiagnostic and inconclusive results than FNA (7.7% vs. 53.8%, P=0.002 and 15.4% vs. 57.7%, P=0.003, respectively) in 26 nodules that underwent both FNA and CNB. CNB showed a marginally higher diagnostic performance for identifying malignancy than FNA (P=0.067). The ultrasonographic features of the anterior margin of isolated macrocalcification were not predictive of malignancy (P>0.999). Thyroid nodules with isolated macrocalcification had a low to intermediate malignancy risk and should not be considered benign nodules. CNB showed a higher diagnostic efficacy than FNA in these nodules.

Thyroid nodules with isolated macrocalcification: Malignancy and diagnostic efficacy of fine-needle aspiration and core needle biopsy

International Nuclear Information System (INIS)

Na, Dong Gyu; Kim, Dae Sik; Kim, Soo Jin; Ryoo, Jae Wook; Jung, So Lyung

2016-01-01

This study was performed to determine the malignancy risk of thyroid nodules with isolated macrocalcification and to evaluate the diagnostic efficacy of fine-needle aspiration (FNA) and core needle biopsy (CNB). From May 2008 to December 2014, a total of 44 patients with isolated macrocalcifications were enrolled from 4,081 consecutive patients who underwent FNA or CNB at a single institution. We assessed the malignancy risk of nodules with isolated macrocalcification. We compared the diagnostic results between FNA and CNB, and the diagnostic efficacy of each procedure was evaluated by the rate of inconclusive results. We compared the diagnostic performance for malignancy between FNA and CNB with a criterion of malignant or atypia/follicular lesion of undetermined significance (indeterminate) diagnostic results. We investigated whether the ultrasonographic feature of isolated macrocalcification was predictive of malignancy. The malignancy risk of nodules with isolated macrocalcification was 16.1% in 31 nodules with final diagnoses and 11.4% in all nodules. CNB demonstrated a significantly lower rate of nondiagnostic and inconclusive results than FNA (7.7% vs. 53.8%, P=0.002 and 15.4% vs. 57.7%, P=0.003, respectively) in 26 nodules that underwent both FNA and CNB. CNB showed a marginally higher diagnostic performance for identifying malignancy than FNA (P=0.067). The ultrasonographic features of the anterior margin of isolated macrocalcification were not predictive of malignancy (P>0.999). Thyroid nodules with isolated macrocalcification had a low to intermediate malignancy risk and should not be considered benign nodules. CNB showed a higher diagnostic efficacy than FNA in these nodules

Effect of media composition, including gelling agents, on isolation of previously uncultured rumen bacteria.

Science.gov (United States)

Nyonyo, T; Shinkai, T; Tajima, A; Mitsumori, M

2013-01-01

The aim of this study was to develop novel anaerobic media using gellan gum for the isolation of previously uncultured rumen bacteria. Four anaerobic media, a basal liquid medium (BM) with agar (A-BM), a modified BM (MBM) with agar (A-MBM), an MBM with phytagel (P-MBM) and an MBM with gelrite (G-MBM) were used for the isolation of rumen bacteria and evaluated for the growth of previously uncultured rumen bacteria. Of the 214 isolates composed of 144 OTUs, 103 isolates (83 OTUs) were previously uncultured rumen bacteria. Most of the previously uncultured strains were obtained from A-MBM, G-MBM and P-MBM, but the predominant cultural members, isolated from each medium, differed. A-MBM and G-MBM showed significantly higher numbers of different OTUs derived from isolates than A-BM (P rumen bacteria were isolated from all media used, the ratio of previously uncultured bacteria to total isolates was increased in A-MBM, P-MBM and G-MBM. © 2012 The Society for Applied Microbiology.

Biosurfactant production by yeasts isolated from hydrocarbon polluted environments.

Science.gov (United States)

Kaur, Kamalpreet; Sangwan, Seema; Kaur, Harpreet

2017-11-03

Thirty-two yeast isolates were retrieved from four soil samples collected from hydrocarbon-polluted locations of Hisar, Haryana, using enrichment culture technique with 1% (v/v) diesel as carbon source. Total nine isolates showing blood agar haemolysis were screened further for biosurfactant production. Yeast isolate, YK32, gave highest 8.4-cm oil displacement which was found to be significantly higher as compared to positive control, 0.2% (w/v) SDS (6.6 cm), followed by 6.2 and 6.0 cm by isolates YK20 and YK21, respectively. Maximum emulsification index was obtained in case of isolates YK20 and YK21 measuring 53.8%, after 6 days of incubation utilizing glucose as carbon source, whereas isolate YK32 was found to be reducing surface tension up to 93 dynes/cm and presented 99.6% degree of hydrophobicity. Olive oil has supported maximum surface tension reduction in isolates YK32 and YK21 equivalent to 53 and 48 dynes/cm and gave 88.3 and 88.5% degree of hydrophobicity, respectively. Diesel was not preferred as carbon source by most of the isolates except YK28 which generated 5.5-cm oil displacement, 25% emulsification index, reduced surface tension to the level of 38 dynes/cm and presented 89% degree of hydrophobicity. Conclusively, isolates YK20, YK21, YK22 and YK32 were marked as promising biosurfactant producers and were subjected to identification. Based on microscopic examination and biochemical peculiarities, isolates YK21 and YK22 might be identified as Candida spp., whereas, isolates YK20 and YK32 might be identified as Saccharomycopsis spp. and Brettanomyces spp., respectively. Interestingly it is the first report indicating Saccharomycopsis spp. and Brettanomyces spp. as a potential biosurfactant producer.

Characterization of bacterial isolates from rotting potato tuber tissue showing antagonism to Dickeya sp. biovar 3 in vitro and in planta

NARCIS (Netherlands)

Czajkowski, R.L.; De Boer, W.J.; Van Veen, J.A.; Van der Wolf, J.M.

2012-01-01

Possibilities for biocontrol of biovar 3 Dickeya sp. in potato were investigated, using bacteria from rotting potato tissue isolated by dilution plating on nonselective agar media. In a plate assay, 649 isolates were screened for antibiosis against Dickeya sp. IPO2222 and for the production of

High Isolation Dual-Polarized Patch Antenna with Hybrid Ring Feeding

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Xian-Jing Lin

2017-01-01

Full Text Available This paper presents a hybrid ring feeding dual-polarized patch antenna with high isolation in a wide working band. The proposed antenna consists of a circular radiating patch printed on the upper horizontal substrate, two pairs of Γ shaped strips printed on two vertical substrates, and a hybrid ring feeding network printed on the lower two horizontal substrates. The proposed antenna adopts Γ shape strips coupled feeding structure to achieve a wide operating band. Furthermore, a hybrid ring feeding structure with high isolation in a wide bandwidth, which is firstly proposed, is applied as feeding network. When one port is excited, the feeding network can realize twice the power cancellation. Thus, high ports isolation characteristics can be obtained. A prototype of the proposed antenna is fabricated and measured. Measured results show that the 10 dB reflection coefficient bandwidths of the two ports are both about 38.7%, with port isolation higher than 40 dB through most of the band, and the cross-polarizations are below −24 dB.

Short communication: In vitro antimicrobial susceptibility of Mycoplasma agalactiae strains isolated from dairy goats.

Science.gov (United States)

Paterna, A; Sánchez, A; Gómez-Martín, A; Corrales, J C; De la Fe, C; Contreras, A; Amores, J

2013-01-01

This study examined the susceptibility to several antimicrobials of 28 isolates of Mycoplasma agalactiae obtained from goats in a region (southeastern Spain) where contagious agalactia is endemic. For each isolate, the minimum inhibitory concentration (MIC) against 12 antimicrobials of the quinolone, macrolide, aminoglycoside, and tetracycline families was determined. The antimicrobials with the lowest MIC were enrofloxacin, ciprofloxacin, tylosin, and doxycycline, all with MIC90 (concentration at which growth of 90% of the isolates is inhibited) <1 µg/mL. Norfloxacin (a quinolone) showed a wide MIC range (0.1-12.8 µg/mL), suggesting a resistance mechanism toward this antimicrobial that was not elicited by enrofloxacin or ciprofloxacin (the other quinolones tested). Erythromycin showed the highest MIC90 such that its use against Mycoplasma agalactiae is not recommended. Finally, Mycoplasma agalactiae isolates obtained from goat herds with clinical symptoms of contagious agalactia featured higher MIC90 and MIC50 (concentration at which growth of 50% of the isolates is inhibited) values for many of the antimicrobials compared with isolates from asymptomatic animals. The relationship between the extensive use of antimicrobials in herds with clinical contagious agalactia and variations in MIC requires further study. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Notable fibrolytic enzyme production by Aspergillus spp. isolates from the gastrointestinal tract of beef cattle fed in lignified pastures.

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Flávia Oliveira Abrão

Full Text Available Fungi have the ability to degrade vegetal cell wall carbohydrates, and their presence in the digestive tract of ruminants can minimize the effects of lignified forage on ruminal fermentation. Here, we evaluated enzyme production by Aspergillus spp. isolates from the digestive tracts of cattle grazed in tropical pastures during the dry season. Filamentous fungi were isolated from rumen and feces by culture in cellulose-based medium. Ninety fungal strains were isolated and identified by rDNA sequence analysis, microculture, or both. Aspergillus terreus was the most frequently isolated species, followed by Aspergillus fumigatus. The isolates were characterized with respect to their cellulolytic, xylanolytic, and lignolytic activity through qualitative evaluation in culture medium containing a specific corresponding carbon source. Carboxymethyl cellulase (CMCase activity was quantified by the reducing sugar method. In the avicel and xilan degradation test, the enzyme activity (EA at 48 h was significantly higher other periods (P < 0.05. Intra- and inter-specific differences in EA were verified, and high levels of phenoloxidases, which are crucial for lignin degradation, were observed in 28.9% of the isolates. Aspergillus terreus showed significantly higher EA for avicelase (3.96 ±1.77 and xylanase (3.13 ±.091 than the other Aspergillus species at 48 h of incubation. Isolates AT13 and AF69 showed the highest CMCase specific activity (54.84 and 33.03 U mg-1 protein, respectively. Selected Aspergillus spp. isolates produced remarkable levels of enzymes involved in vegetal cell wall degradation, suggesting their potential as antimicrobial additives or probiotics in ruminant diets.

Isolation and functional characterization of a biosurfactant produced by Lactobacillus paracasei.

Science.gov (United States)

Gudiña, Eduardo J; Teixeira, José A; Rodrigues, Lígia R

2010-03-01

In this study, the crude biosurfactant produced by a Lactobacillus paracasei strain isolated in a Portuguese dairy industry was characterized. The minimum surface tension (41.8mN/m) and the critical micelle concentration (2.5mg/ml) obtained were found to be similar to the values previously reported for biosurfactants isolated from other lactobacilli. The biosurfactant was found to be stable to pH changes over a range from 6 to 10, being more effective at pH 7, and showed no loss of surface activity after incubation at 60 degrees C for 120h. Although the biosurfactant chemical composition has not been determined yet, a fraction was isolated through acidic precipitation, which exhibited higher surface activity as compared with the crude biosurfactant. Furthermore, this isolated biosurfactant showed antimicrobial and anti-adhesive activities against several pathogenic microorganisms. In addition, L. paracasei exhibited a strong autoaggregating phenotype, which was maintained after washing and resuspending the cells in PBS, meaning that this attribute must be related to cell surface components and not to excreted factors. The autoaggregation ability exhibited by this strain, together with the antimicrobial and anti-adhesive properties observed for this biosurfactant opens the possibility for its use as an effective probiotic strain.

Cellulose biosynthesis in higher plants

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Krystyna Kudlicka

2014-01-01

Full Text Available Knowledge of the control and regulation of cellulose synthesis is fundamental to an understanding of plant development since cellulose is the primary structural component of plant cell walls. In vivo, the polymerization step requires a coordinated transport of substrates across membranes and relies on delicate orientations of the membrane-associated synthase complexes. Little is known about the properties of the enzyme complexes, and many questions about the biosynthesis of cell wall components at the cell surface still remain unanswered. Attempts to purify cellulose synthase from higher plants have not been successful because of the liability of enzymes upon isolation and lack of reliable in vitro assays. Membrane preparations from higher plant cells incorporate UDP-glucose into a glucan polymer, but this invariably turns out to be predominantly β -1,3-linked rather than β -1,4-linked glucans. Various hypotheses have been advanced to explain this phenomenon. One idea is that callose and cellulose-synthase systems are the same, but cell disruption activates callose synthesis preferentially. A second concept suggests that a regulatory protein as a part of the cellulose-synthase complex is rapidly degraded upon cell disruption. With new methods of enzyme isolation and analysis of the in vitro product, recent advances have been made in the isolation of an active synthase from the plasma membrane whereby cellulose synthase was separated from callose synthase.

Frequency of isolation and antibiotic resistance patterns of bacterial isolates from wound infections

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Stojanović-Radić, Z.

2016-12-01

Full Text Available Six hundred and thirteen bacterial strains were isolated from wound swabs and the isolates were identified on the basis of growth on differential and selective media. In order to test the sensitivity of isolated strains to different antibiotics, the disc diffusion method, according to EUCAST protocol v 5.0 was used. The most common species isolated from wound swabs was Staphylococcus epidermidis (18.4%, followed by Staphylococcus aureus, Pseudomonas aeruginosa and Enterococcus faecalis (16.8%, 12.7% and 10.4%, respectively. The maximum resistance of Gram-positive cocci was observed to penicillin and the lowest to linezolid. Gram-negative bacteria showed the highest resistance to tetracyclines, while the same strains demonstrated the highest sensitivity to polypeptide antibiotics. Comparison of the resistance patterns of Gramnegative and Gram-positive bacterial strains showed significant difference in the tetracycline efficiency.

Single-provenance mature conifers show higher non-structural carbohydrate storage and reduced growth in a drier location.

Science.gov (United States)

Piper, Frida I; Fajardo, Alex; Hoch, Günter

2017-08-01

Since growth is more sensitive to drought than photosynthesis, trees inhabiting dry regions are expected to exhibit higher carbohydrate storage and less growth than their conspecifics from more humid regions. However, the same pattern can be the result of different genotypes inhabiting contrasting humidity conditions. To test if reduced growth and high carbohydrate storage are environmentally driven by drought, we examined the growth and non-structural carbohydrate (NSC) concentrations in single-provenance stands of mature trees of Pinus contorta Douglas and Pinus ponderosa Douglas ex C. Lawson planted at contrasting humidity conditions (900 versus 300 mm of annual precipitation) in Patagonia, Chile. Individual tree growth was measured for each species and at each location as mean basal area increment of the last 10 years (BAI10), annual shoot elongation for the period 2011-14, and needle length for 2013 and 2014 cohorts. Additionally, needle, branch, stem sapwood and roots were collected from each sampled tree to determine soluble sugars, starch and total NSC concentrations. The two species showed lower mean BAI10 and 2013 needle length in the dry site; P. ponderosa also had lower annual shoot extension for 2011 and 2014, and lower 2014 needle length, in the dry than in the mesic site. By contrast, NSC concentrations of all woody tissues for both species were either similar or higher in the dry site when compared with the mesic site. Patterns of starch and sugars were substantially different: starch concentrations were similar between sites except for roots of P. ponderosa, which were higher in the dry site, while sugar concentrations of all woody tissues in both species were higher in the dry site. Overall, our study provides evidence that reduced growth along with carbon (C) accumulation is an environmentally driven response to drought. Furthermore, the significant accumulation of low-molecular weight sugars in the dry site is compatible with a prioritized C

Phylogenetic analysis, fumonisin production and pathogenicity of Fusarium fujikuroi strains isolated from rice in the Philippines.

Science.gov (United States)

Cruz, Alejandra; Marín, Patricia; González-Jaén, M Teresa; Aguilar, Kristel Grace I; Cumagun, Christian Joseph R

2013-09-01

Fusarium fujikuroi Nirenberg is a maize and rice pathogen causing important agricultural losses and produces fumonisins - mycotoxins which pose health risk to humans and farm animals. However, little information is available about the phylogenetics of this species and its ability to produce fumonisins in rice. We studied 32 strains isolated from rice in the Philippines and performed a phylogenetic analysis using the partial sequence of Elongation Factor 1 alpha (EF-1α) including isolates belonging to closely related species. Fumonisin B1 (FB1 ) production was analyzed in 7-day-old cultures grown in fumonisin-inducing medium by an enzyme-linked immunosorbent assay-based method and by real-time reverse transcriptase-polymerase chain reaction using primers for FUM1 gene, a key gene in fumonisin biosynthesis. Nucleotide diversities per site (π) were 0.00024 ± 0.00022 (standard deviation) for the 32 F. fujikuroi strains from the Philippines and 0.00189 ± 0.00143 for all 34 F. fujikuroi strains, respectively. F. fujikuroi isolates grouped into one cluster separated from the rest of isolates belonging to the closely related F. proliferatum and showed very low variability, irrespective of their geographic origin. The cluster containing strains of F. proliferatum showed higher intraspecific variability than F. fujikuroi. Thirteen of the 32 strains analyzed were FB1 producers (40.62%), with production ranging from 0.386 to 223.83 ppm. All isolates analyzed showed FUM1 gene expression above 1 and higher than the CT value of the non-template control sample. Both seedling stunting and elongation were induced by the isolates in comparison with the control. F. fujikuroi are distinct from F. proliferatum isolates based on phytogenetic analysis and are potential fumonisin producers because all are positive for FUM1 gene expression. No relationship between fumonisin production and pathogenicity could be observed. © 2013 Society of Chemical Industry.

The Growth of Higher Educators for Social Justice: Collaborative Professional Development in Higher Education

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Molly K. Ness, PhD

2010-08-01

Full Text Available In this article, we investigate what happened when, contrary to the typical isolation of faculty in higher education, a group of higher educators from various disciplines in a graduate school of education met regularly to discuss issues related to our teaching and social justice. More specifically, we explored the following research question: How does collaboration among higher educators from various disciplines shape their beliefs and practices of teaching for social justice? Over three years of collaboration and conversation, not only did we expand our own knowledge and understandings of notions of social justice, but we began to take important steps towards increasing our social justice actions in our teaching. This article explores our efforts to create a self-directed professional development group of higher educators and provides suggestions for similarly interested higher educators.

Improvement of vitamin B-6 production by gamma radiation in bacterial isolates from soil sample

International Nuclear Information System (INIS)

Trongpanich, Yanee; Anutrakunchai, Chitchanok; Piadang, Nattayana

2006-09-01

A vitamin B-6 producing bacterium, Rhizobium sp. 6.1C1 was isolated from soil and produced vitamin B-6 (mainly pyridoxamine) 0.27 mg per liter. Rhizobium sp. 6.1C1 is mesophile bacterium which was not able to grow at over 4 0C. The objective of this study was to improve vitamin B-6 production in high temperature by gamma radiation. The result showed that 677 mutant isolates which were obtained from irradiation dose 0.8 and 1 kGy, were able to grow at 5 0C. Only 4 isolates (08-361, 10-3, 10-94 and 10-98) showed high amount of vitamin B-6 per mg protein. From the results of optimum temperature and initial pH of medium showed high amount of vitamin B-6 per mg protein. From the results of optimum temperature and initial pH of medium showed that isolate 08-361 showed higher amount of vitamin b-6 than wild type. However, this value of vitamin B-6 from this mutant was lower than that when screening. Forms of produced vitamin B-6 from mutant were identified by HPLC. The result showed produced vitamin B-6 were PM and PMP, similar with wild type. Effect of gamma radiation stability of mutant is further study.

Social Isolation Stress Induces Anxious-Depressive-Like Behavior and Alterations of Neuroplasticity-Related Genes in Adult Male Mice

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Alessandro Ieraci

2016-01-01

Full Text Available Stress is a major risk factor in the onset of several neuropsychiatric disorders including anxiety and depression. Although several studies have shown that social isolation stress during postweaning period induces behavioral and brain molecular changes, the effects of social isolation on behavior during adulthood have been less characterized. Aim of this work was to investigate the relationship between the behavioral alterations and brain molecular changes induced by chronic social isolation stress in adult male mice. Plasma corticosterone levels and adrenal glands weight were also analyzed. Socially isolated (SI mice showed higher locomotor activity, spent less time in the open field center, and displayed higher immobility time in the tail suspension test compared to group-housed (GH mice. SI mice exhibited reduced plasma corticosterone levels and reduced difference between right and left adrenal glands. SI showed lower mRNA levels of the BDNF-7 splice variant, c-Fos, Arc, and Egr-1 in both hippocampus and prefrontal cortex compared to GH mice. Finally, SI mice exhibited selectively reduced mGluR1 and mGluR2 levels in the prefrontal cortex. Altogether, these results suggest that anxious- and depressive-like behavior induced by social isolation stress correlates with reduction of several neuroplasticity-related genes in the hippocampus and prefrontal cortex of adult male mice.

Ciprofloxacin susceptibility of Pseudomonas aeruginosa isolates from keratitis

DEFF Research Database (Denmark)

Lomholt, JA; Kilian, Mogens

2003-01-01

keratitis, endophthalmitis, contact lens associated red eye (CLARE), and contact lens storage cases showed MIC values below 1 mg/l. Several allelic forms of gyrA and a single variation in the mexR gene product were detected in 10 ciprofloxacin susceptible strains. CONCLUSIONS: The vast majority of eye......AIM: To examine the ciprofloxacin susceptibility of 106 Pseudomonas aeruginosa eye isolates from the United Kingdom, Denmark, India, the United States, and Australia, and to determine the molecular mechanisms of resistance. METHODS: Ciprofloxacin susceptibility was tested by an agar dilution method...... isolates of P aeruginosa from European countries are fully susceptible to ciprofloxacin and the concentration of ciprofloxacin eye drops used for local treatment (3000 mg/l) exceeds MIC values for strains recorded as resistant. Mutations in more than one target gene were associated with higher MIC values....

Ciprofloxacin susceptibility of Pseudomonas aeruginosa isolates from keratitis

DEFF Research Database (Denmark)

Lomholt, JA; Kilian, Mogens

2003-01-01

AIM: To examine the ciprofloxacin susceptibility of 106 Pseudomonas aeruginosa eye isolates from the United Kingdom, Denmark, India, the United States, and Australia, and to determine the molecular mechanisms of resistance. METHODS: Ciprofloxacin susceptibility was tested by an agar dilution method...... keratitis, endophthalmitis, contact lens associated red eye (CLARE), and contact lens storage cases showed MIC values below 1 mg/l. Several allelic forms of gyrA and a single variation in the mexR gene product were detected in 10 ciprofloxacin susceptible strains. CONCLUSIONS: The vast majority of eye...... isolates of P aeruginosa from European countries are fully susceptible to ciprofloxacin and the concentration of ciprofloxacin eye drops used for local treatment (3000 mg/l) exceeds MIC values for strains recorded as resistant. Mutations in more than one target gene were associated with higher MIC values....

ERP for Romanian Higher Education

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2007-01-01

Full Text Available Also most of the big ERP providers provide solutions for higher education, including SAP AG, Oracle, JD Eduards, Peoplesoft, universities preferr other specialized applications which better fit their specific needs. This paper presents the advantages of an integrated solution for higher education and analyzes the solutions offered for this sector by the Romanian ERP market. The conlusion is more like an invitation to discussion about possible solutions to the present Romanian university situation: low budgets, changing regulations, isolated, self-developed applications.

Reforming Iraqi Journalism and Mass Communication Higher Education: Adapting the UNESCO Model Curricula for Journalism Education to Iraqi Higher Education

Science.gov (United States)

Pavlik, John V.; Laufer, Peter D.; Burns, David P.; Ataya, Ramzi T.

2012-01-01

Journalism and mass communication higher education in Iraq is well established but largely isolated from global developments since the 1970s. In the post-Iraq war period, the United Nations Educational, Scientific and Cultural Organization (UNESCO) implemented a multiyear project to work with the leadership of Iraqi higher education to help update…

[A 53-year-old man with herpes encephalitis showing acceleration of improvement in higher brain function after general anesthesia with sevoflurane: a case report].

Science.gov (United States)

Togashi, Naohiko; Kaida, Kenichi; Hongo, Yu; Ogawa, Go; Ishikawa, Yukinobu; Takeda, Katsuhiko; Kamakura, Keiko

2014-01-01

We experienced a right-handed 53-year-old man who presented with disturbance of consciousness and fever. Herpes simplex encephalitis (HSE) was diagnosed based on the detection of herpes simplex virus DNA in the cerebrospinal fluid. The administration of acyclovir for 42 days improved his consciousness level. Drowsiness, fever and seizures reappeared 20 days after stopping acyclovir treatment (day 67) and he responded well to vidarabine and methylprednisolone pulse therapy. An assessment of aphasia on day 98 revealed transcortical sensory aphasia. Brain MRI showed lesion in the left temporal lobe, bilateral insular cortexes and bilateral frontal lobe. His higher brain dysfunction continued. On day 156, he underwent hip replacement arthroplasty under general anesthesia sevoflurane. His higher brain dysfunction rapidly improved thereafter. We concluded that the accelerated improvement in our patient's higher brain function was related to the protective effect of sevoflurane. Some reports also show the protective effects of sevoflurane in experimental allergic encephalomyelitis by inhibition of T cell activation. These protective and anti-inflammatory effects may explain the accelerated improvement in higher brain function after general anesthesia.

Genetic characterization of commercial Saccharomyces cerevisiae isolates recovered from vineyard environments.

Science.gov (United States)

Schuller, Dorit; Pereira, Leonor; Alves, Hugo; Cambon, Brigitte; Dequin, Sylvie; Casal, Margarida

2007-08-01

One hundred isolates of the commercial Saccharomyces cerevisiae strain Zymaflore VL1 were recovered from spontaneous fermentations carried out with grapes collected from vineyards located close to wineries in the Vinho Verde wine region of Portugal. Isolates were differentiated based on their mitochondrial DNA restriction patterns and the evaluation of genetic polymorphisms was carried out by microsatellite analysis, interdelta sequence typing and pulsed-field gel electrophoresis (PFGE). Genetic patterns were compared to those obtained for 30 isolates of the original commercialized Zymaflore VL1 strain. Among the 100 recovered isolates we found a high percentage of chromosomal size variations, most evident for the smaller chromosomes III and VI. Complete loss of heterozygosity was observed for two isolates that had also lost chromosomal heteromorphism; their growth and fermentative capacity in a synthetic must medium was also affected. A considerably higher number of variant patterns for interdelta sequence amplifications was obtained for grape-derived strains compared to the original VL1 isolates. Our data show that the long-term presence of strain VL1 in natural grapevine environments induced genetic changes that can be detected using different fingerprinting methods. The observed genetic changes may reflect adaptive mechanisms to changed environmental conditions that yeast cells encounter during their existence in nature. (c) 2007 John Wiley & Sons, Ltd.

Characterization of Fusobacterium necrophorum isolated from llama and alpaca.

Science.gov (United States)

Kumar, Amit; Anderson, David; Amachawadi, Raghavendra G; Nagaraja, Tiruvoor G; Narayanan, Sanjeev K

2013-07-01

Fusobacterium necrophorum, a Gram-negative, anaerobic bacterium, is an opportunistic animal and human pathogen that causes a variety of infections termed necrobacillosis. There are 2 subspecies of F. necrophorum (subsp. necrophorum and subsp. funduliforme) that differ morphologically and biochemically and in virulence. Leukotoxin, a secreted protein, is considered to be the major virulence factor. In camelids, F. necrophorum causes a variety of infections, generally involving the lips, tongue, pharynx, interdigital spaces, foot pad, larynx, mandible, or maxillary bones. The objective of the current study was to characterize the presumptive Fusobacterium isolates from a variety of necrotic infections in llama (Lama glama) and alpaca (Vicugna pacos) and determine whether the strains possess leukotoxin activities. A total of 7 isolates from alpaca and 2 isolates from llama were characterized. Based on growth characteristics in broth culture, and biochemical and polymerase chain reaction analyses, all 9 isolates belonged to subsp. necrophorum and possessed the putative hemagglutinin gene. Western blot analysis with antileukotoxin antibodies raised in rabbit showed the presence of leukotoxin protein in the culture supernatant of all isolates. Furthermore, flow cytometry of the culture supernatants demonstrated cytotoxicity to bovine and alpaca polymorphonuclear leukocytes (PMNs). The extent of cytotoxicity to either alpaca or bovine PMNs differed among camelid strains. The cytotoxicity of many of the camelid strains was higher (P llama and alpaca are similar to bovine isolates, and leukotoxin may be a major virulence factor.

Use of Limiting Dilution Method for Isolation of Nucleus Pulposus Mesenchymal Stem/Progenitor Cells and Effects of Plating Density on Biological Characteristics and Plasticity

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Linghan Lin

2017-01-01

Full Text Available Objectives. To evaluate the effects of the limiting dilution method and plating density in rat nucleus pulposus mesenchymal stem/progenitor cells (NPMSCs. Materials and Methods. Nucleus pulposus tissues were isolated from 12-week-old male Sprague-Dawley rats and NPMSCs were isolated using limiting dilution method. Cells were then classified into 3 groups according to plating density. Cell morphologies were observed, and colony-forming units, migration abilities, proliferative capacities, cell cycle percentages, multilineage differentiation capacities, stem cell biomarker expression levels, and immunophenotyping were also examined in each group. Results. Low density group (LD had higher morphological homogeneity, stronger colony-forming ability, higher cell proliferation capacity, and enhanced cell migration ability relative to the other two groups (p<0.05. Moreover, LD had more cells entering S phase, with fewer cells arrested in G0/G1 phase (p<0.05. While all three density groups showed a multilineage differentiation potential, LD showed a higher degree of observed and semiquantified lineage specific staining (p<0.05. Furthermore, LD displayed higher expression levels of stem cell biomarkers (Nanog, Oct4, and Sox2 and showed higher percentages of CD29+, CD44+, and CD90+ cells (p<0.05 following flow cytometry analysis. Conclusions. Limiting dilution method is suggested when isolating NPMSCs as a means of improving cell activity and plasticity.

Molecular characterization of Mycobacterium tuberculosis isolates from Tehran, Iran by restriction fragment length polymorphism analysis and spoligotyping

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Seifu Gizaw Feyisa

2016-04-01

Full Text Available Abstract: INTRODUCTION Characterization of Mycobacterium tuberculosis (MTB isolates by DNA fingerprinting has contributed to tuberculosis (TB control. The aim of this study was to determine the genetic diversity of MTB isolates from Tehran province in Iran. METHODS MTB isolates from 60 Iranian and 10 Afghan TB patients were fingerprinted by standard IS6110-restriction fragment length polymorphism (RFLP analysis and spoligotyping. RESULTS The copy number of IS6110 ranged from 10-24 per isolate. The isolates were classified into 22 clusters showing ≥ 80% similarity by RFLP analysis. Fourteen multidrug-resistant (MDR isolates were grouped into 4 IS6110-RFLP clusters, with 10 isolates [71% (95% CI: 45-89%] in 1 cluster, suggesting a possible epidemiological linkage. Eighteen Iranian isolates showed ≥ 80% similarity with Afghan isolates. There were no strains with identical fingerprints. Spoligotyping of 70 isolates produced 23 distinct patterns. Sixty (85.7% isolates were grouped into 13 clusters, while the remaining 10 isolates (14.2% were not clustered. Ural (formerly Haarlem4 (n = 22, 31.4% was the most common family followed by Central Asian strain (CAS (n = 18, 25.7% and T (n = 9, 12.8% families. Only 1strain was characterized as having the Beijing genotype. Among 60 Iranian and 10 Afghan MTB isolates, 25% (95% CI: 16-37 and 70% (95% CI: 39-89 were categorized as Ural lineage, respectively. CONCLUSIONS A higher prevalence of Ural family MTB isolates among Afghan patients than among Iranian patients suggests the possible transmission of this lineage following the immigration of Afghans to Iran.

Isolation and characterization of avian metapneumovirus from chickens in Korea.

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Kwon, Ji-Sun; Lee, Hyun-Jeong; Jeong, Seung-Hwan; Park, Jeong-Yong; Hong, Young-Ho; Lee, Youn-Jeong; Youn, Ho-Sik; Lee, Dong-Woo; Do, Sun-Hee; Park, Seung-Yong; Choi, In-Soo; Lee, Joong-Bok; Song, Chang-Seon

2010-03-01

Avian metapneumovirus (aMPV) causes upper respiratory tract infections in chickens and turkeys. Although the swollen head syndrome (SHS) associated with aMPV in chickens has been reported in Korea since 1992, this is the study isolating aMPV from chickens in this country. We examined 780 oropharyngeal swab or nasal turbinate samples collected from 130 chicken flocks to investigate the prevalence of aMPV and to isolate aMPV from chickens from 2004-2008. Twelve aMPV subtype A and 13 subtype B strains were detected from clinical samples by the aMPV subtype A and B multiplex real-time reverse transcription polymerase chain reaction (RRT-PCR). Partial sequence analysis of the G glycoprotein gene confirmed that the detected aMPVs belonged to subtypes A and B. Two aMPVs subtype A out of the 25 detected aMPVs were isolated by Vero cell passage. In animal experiments with an aMPV isolate, viral RNA was detected in nasal discharge, although no clinical signs of SHS were observed in chickens. In contrast to chickens, turkeys showed severe nasal discharge and a relatively higher titer of viral excretion than chickens. Here, we reveal the co-circulation of aMPV subtypes A and B, and isolate aMPVs from chicken flocks in Korea.

Comprehensive Molecular Characterization of Escherichia coli Isolates from Urine Samples of Hospitalized Patients in Rio de Janeiro, Brazil

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Ana Carolina C. Campos

2018-02-01

Full Text Available Urinary tract infections (UTIs are often caused by Escherichia coli. Their increasing resistance to broad-spectrum antibiotics challenges the treatment of UTIs. Whereas, E. coli ST131 is often multidrug resistant (MDR, ST69 remains susceptible to antibiotics such as cephalosporins. Both STs are commonly linked to community and nosocomial infections. E. coli phylogenetic groups B2 and D are associated with virulence and resistance profiles making them more pathogenic. Little is known about the population structure of E. coli isolates obtained from urine samples of hospitalized patients in Brazil. Therefore, we characterized E. coli isolated from urine samples of patients hospitalized at the university and three private hospitals in Rio de Janeiro, using whole genome sequencing. A high prevalence of E. coli ST131 and ST69 was found, but other lineages, namely ST73, ST648, ST405, and ST10 were also detected. Interestingly, isolates could be divided into two groups based on their antibiotic susceptibility. Isolates belonging to ST131, ST648, and ST405 showed a high resistance rate to all antibiotic classes tested, whereas isolates belonging to ST10, ST73, ST69 were in general susceptible to the antibiotics tested. Additionally, most ST69 isolates, normally resistant to aminoglycosides, were susceptible to this antibiotic in our population. The majority of ST131 isolates were ESBL-producing and belonged to serotype O25:H4 and the H30-R subclone. Previous studies showed that this subclone is often associated with more complicated UTIs, most likely due to their high resistance rate to different antibiotic classes. Sequenced isolates could be classified into five phylogenetic groups of which B2, D, and F showed higher resistance rates than groups A and B1. No significant difference for the predicted virulence genes scores was found for isolates belonging to ST131, ST648, ST405, and ST69. In contrast, the phylogenetic groups B2, D and F showed a higher

Isolated tumor endothelial cells maintain specific character during long-term culture

International Nuclear Information System (INIS)

Matsuda, Kohei; Ohga, Noritaka; Hida, Yasuhiro; Muraki, Chikara; Tsuchiya, Kunihiko; Kurosu, Takuro; Akino, Tomoshige; Shih, Shou-Ching

2010-01-01

Tumor angiogenesis is necessary for solid tumor progression and metastasis. Increasing evidence indicates that tumor endothelial cells (TECs) are more relevant to the study of tumor angiogenesis than normal endothelial cells (NECs) because their morphologies and gene expression are different from NECs. However, it is challenging to isolate and culture large numbers of pure ECs from tumor tissue since the percentage of ECs is only about 1-2% and tumor cells and fibroblasts easily overgrow them. In addition, there has been concern that isolated TECs may lose their special phenotype once they are dissociated from tumor cells. In this study, we have successfully purified murine TECs from four different human tumor xenografts and NECs from murine dermal tissue. Isolated ECs expressed endothelial markers, such as CD31, VE-cadherin (CD144), and endoglin (CD105), for more than 3 months after isolation. TECs maintained tumor endothelial-specific markers, such as tumor endothelial marker 8 (TEM8) and aminopeptidase N (APN), as in tumor blood vessels in vivo. In addition, TECs were more proliferative and motile than NECs. TECs showed a higher response to VEGF and higher expression of VEGF receptors-1 and -2 than NECs did. Stem cell antigen-1 was up-regulated in all four TECs, suggesting that they have a kind of stemness. Cultured TECs maintain distinct biological differences from NECs as in vivo. In conclusion, it was suggested that TECs are relevant material for tumor angiogenesis research.

Isolation, characterization, antibiogram and pathology of Pasteurella multocida isolated from pigs

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Mamta Tigga

2014-05-01

Full Text Available Aim: Isolation, characterization and antibiogram of Pasteurella multocida from diseased pigs of district Durg of Chhattisgarh, and to study pathological changes caused by swine pasteurellosis. Materials and Methods: An outbreak of swine pasteurellosis was suspected in pigs of Ruwabandha (Bhilai, Anjora, Somni, Tedesara, Tirgajhola villages of Durg district in Chhattisgarh, India during August and September of 2011. Nasal Swabs and blood samples from ailing pigs and heart blood and impression smears from morbid pigs were processed for detection and isolation of P. multocida by bacteriological methods. Detailed necropsy was conducted and gross and histopathological lesions were recorded. The test Isolates were subjected to antimicrobial sensitivity profile by disc-diffusion method. Results: The blood smears from heart blood and tissue impression smears revealed teaming of bipolar organisms indicating the presence of Pasteurella spp. The isolates obtained were subjected to Gram's staining for checking the purity and bipolar morphology and characterized biochemically. Gross lesions included severe acute pneumonia and haemorrhages in lungs, petechial haemorrhages on serous membranes and other visceral organs. On histopathological examination, lungs showed typical fibrinous bronchopneumonia, multifocal suppuration. All the isolates of P. multocida were 100% sensitive to Amoxicillin, Gentamicin, Enrofloxacin and showed100% resistance to Ceftizoxim and Cloxacillin. Conclusion: Gross and microscopic lesions in dead animals are of great diagnostic value and are of characteristic of P. multocida infection. Cultural, morphological and biochemical characters are useful to rule out the causative agent as P. multocida. Antibiotic sensitivity pattern of the isolates should routinely be carried out for knowing the antibiotic resistance trends in an endemic area.

Evaluation of Mycelium Growth Rate and Yield of White Button Mushroom Isolates (Agaricus bisporus in Iran

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Mohammad Javad Ahmadi Lahijani

2017-10-01

using LSD test at 5% significance level. Results and discussion: There were significant differences among isolates based on mycelium growth rate and yield. In PDA medium, 2200 isolate showed the fastest mycelium growth rate with 1.9 mm.day-1 and final colony diameter of 8.1 cm. were This isolate also showed the fastest mycelium growth rate on CYM medium and covering the spawn and compost media surfaces, and produced the highest yield along with A15a isolate (A15a and 2200 with 22.1 and 19.4 kg.m-2, respectively. Magnum d with mycelium growth rate of 0.7 mm.day-1 and final colony diameter of 3.1 cm showed the slowest mycelium growth rate. On average, 75% of isolates were grouped in slow mycelium growth rate class and 25% were placed in fast mycelium growth rate class. Isolates A15a, 2200, A15, M7219 and F64d showed fast mycelium growth rate. All of the isolates showed filamentous mycelium growth type and no abnormal mycelium growth type was observed. Isolate A15a with 50% coverage of compost surface during the first 5 days and 90% during the 15 days showed the fastest mycelium growth rate on this medium, followed by isolates F64d, 2200 and A15a. Normal mycelium growth rate on compost medium varied from 6-8 to sometimes 10-12 mm.day-1 (Farsi and Pooyanfar, 2011. There was a high positive correlation between mycelium growth rate and the yield component, so that isolates with faster mycelium growth rate produced higher yield. Farsi and Gordan, (2001 also reported significant positive correlation between filamentous mycelium type and yield, so that isolates with filamentous mycelium growth type and high mycelium growth rate produced higher yield. Faster mycelium growth rate is considered as a desire characteristic in mushroom cultivation due to the reduction of contamination risk of other micro-organisms (Oie, 2003. Conclusion: There was a high significant difference among white button mushroom isolates in terms of mycelium growth rate and yield. Isolates with faster

Bioconversion of glycerol for bioethanol production using isolated Escherichia coli SS1

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Sheril Norliana Suhaimi

2012-06-01

Full Text Available Bioconverting glycerol into various valuable products is one of glycerol's promising applications due to its high availability at low cost and the existence of many glycerol-utilizing microorganisms. Bioethanol and biohydrogen, which are types of renewable fuels, are two examples of bioconverted products. The objectives of this study were to evaluate ethanol production from different media by local microorganism isolates and compare the ethanol fermentation profile of the selected strains to use of glucose or glycerol as sole carbon sources. The ethanol fermentations by six isolates were evaluated after a preliminary screening process. Strain named SS1 produced the highest ethanol yield of 1.0 mol: 1.0 mol glycerol and was identified as Escherichia coli SS1 Also, this isolated strain showed a higher affinity to glycerol than glucose for bioethanol production.

Efficient Isolation of Cardiac Stem Cells from Brown Adipose

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Zhiqiang Liu

2010-01-01

Full Text Available Cardiac stem cells represent a logical cell type to exploit in cardiac regeneration. The efficient harvest of cardiac stem cells from a suitable source would turn promising in cardiac stem cell therapy. Brown adipose was recently found to be a new source of cardiac stem cells, instrumental to myocardial regeneration. Unfortunately, an efficient method for the cell isolation is unavailable so far. In our study we have developed a new method for the efficient isolation of cardiac stem cells from brown adipose by combining different enzymes. Results showed that the total cell yield dramatically increased (more than 10 times, P<.01 compared with that by previous method. The content of CD133-positive cells (reported to differentiate into cardiomyocytes with a high frequency was much higher than that in the previous report (22.43% versus 3.5%. Moreover, the isolated cells could be the efficiently differentiated into functional cardiomyocytes in optimized conditions. Thus, the new method we established would be of great use in further exploring cardiac stem cell therapy.

Isolation, characterization, virulence and immunogenicity testing of field isolates of Pasteurella multocida, Staphylococcus aureus, and Streptococcus agalactiae in laboratory settings.

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Qudratullah; Muhammad, G; Saqib, M; Bilal, M Qamar

2017-08-01

The present study was designed to investigate isolation, characterization, virulence and immunogenicity testing of field isolates of Pasteurella multocida, Staphylococcus aureus, and Streptococcus agalactiae in rabbits and mice. Isolates of P. multocida, S. aureus and Str. agalactiae recovered from field cases of Hemorragic septicemia and mastitis were scrutinized for virulence/pathogenicity and immunogenicity. Mouse LD 50 of P. multocida showed that P. multocida isolate No.1 was more virulent than isolates No. 2 and 3. Virulence of isolate No.1S. aureus and Str. agalactiae revealed that 100, 80% rabbits died within 18h of inoculation. Seven-digit numerical profiles of these 4 isolates with API ® Staph test strips isolates, No.1 (6736153) showed good identification (S. aureus id=90.3%). Indirect ELISA-based serum antibody titers to P. multocida isolate No.1, S. aureus No.1, Str. agalactiae, isolate No.1 elicited high antibody titers 1.9, 1.23, 1.12 respectively. All the pathogens of Isolate No. 1 (P. multocida, S. aureus Str. agalactiae), were high antibody than others isolates. Copyright © 2017 Elsevier B.V. All rights reserved.

Isolation and Characterization of Pollulan Produced by a Local Isolate of Aureobasidium Pullulans

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Kassim, Mohammad Bashir Ismail [محمد بشيراسماعيل قاسم

2000-01-01

A local isolate of Aureobasidium pullulans was obtained from fig leaves surface. The isolate was identified as A. pullulans on the basis of appearance of polymorphism in the colonies, melanin pigment and pullulan production in shake flask cultures. Pullulan production by the local isolate of A pullulans was two thirds of that produced by ATCC 42023. The studies of physico — chemical properties, chemical analysis, sugar composition periodate oxidation and smith degradation showed that the pull...

Molecular identification of clinical Nocardia isolates from India.

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Rudramurthy, Shivaprakash M; Honnavar, Prasanna; Kaur, Harsimran; Samanta, Palash; Ray, Pallab; Ghosh, Anup; Chakrabarti, Arunaloke

2015-10-01

The epidemiology of nocardiosis is evolving with increasing number of Nocardia spp. causing human infection. In recent years, molecular techniques have been used to identify Nocardia spp. There are limited data available on the spectrum of Nocardia spp. isolated from clinical samples in India. Here, a molecular study was carried on 30 clinical isolates maintained in our National Culture Collection to evaluate the techniques used for identifying the agents. The isolates were identified by sequencing two promising genes: the 16S rRNA gene and hsp65. Both hsp65 and the 16S rRNA gene could reliably identify 90 % of Nocardia isolates, i.e. N. farcinica, N. cyriacigeorgica, N. brasiliensis, N. otitidiscaviarum, N. amamiensis and N. pneumoniae. The mean percentage dissimilarity of sequence identification was higher using the hsp65 gene (4 %, range 0-7.9 %) compared with the 16S rRNA gene (2.3 %, range 0-8.9 %). Two isolates that showed ambiguous results in both the short segment of the 16S rRNA gene and hsp65 sequences could be resolved by sequencing a larger fragment (∼1000 bp) of the 16S rRNA gene. Both of these isolates were identified as N. beijingensis with similarities of 99.8 and 100 % compared with the standard strain. Genotyping of N. cyriacigeorgica strains was performed using hsp65 gene sequences and compared with previously described genotypes. Our N. cyriacigeorgica isolates belonged to genotype 1 (n = 4) and genotype 2 (n = 2). The present study highlights a wide spectrum of Nocardia spp. in India and emphasizes the need for molecular techniques for identification to the species level.

Discrete optimization of isolator locations for vibration isolation systems: An analytical and experimental investigation

Energy Technology Data Exchange (ETDEWEB)

Ponslet, E.R.; Eldred, M.S. [Sandia National Labs., Albuquerque, NM (United States). Structural Dynamics Dept.

1996-05-17

An analytical and experimental study is conducted to investigate the effect of isolator locations on the effectiveness of vibration isolation systems. The study uses isolators with fixed properties and evaluates potential improvements to the isolation system that can be achieved by optimizing isolator locations. Because the available locations for the isolators are discrete in this application, a Genetic Algorithm (GA) is used as the optimization method. The system is modeled in MATLAB{trademark} and coupled with the GA available in the DAKOTA optimization toolkit under development at Sandia National Laboratories. Design constraints dictated by hardware and experimental limitations are implemented through penalty function techniques. A series of GA runs reveal difficulties in the search on this heavily constrained, multimodal, discrete problem. However, the GA runs provide a variety of optimized designs with predicted performance from 30 to 70 times better than a baseline configuration. An alternate approach is also tested on this problem: it uses continuous optimization, followed by rounding of the solution to neighboring discrete configurations. Results show that this approach leads to either infeasible or poor designs. Finally, a number of optimized designs obtained from the GA searches are tested in the laboratory and compared to the baseline design. These experimental results show a 7 to 46 times improvement in vibration isolation from the baseline configuration.

Antioxidant Activity of Whey from Milk Fermented with Lactobacillus Species Isolated from Nigerian Fermented Foods

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Ifeoma Korie

2010-01-01

Full Text Available Eight Lactobacillus isolates obtained from five indigenous fermented foods (ogi, ogi baba, wara, kunnu and ugba were investigated. Wara is a dairy-based food while the others are not dairy-based. The bacteria were isolated on MRS agar and purified by successive streaking on the same medium. The whey fraction of skimmed milk fermented with each isolate was assayed for radical scavenging effects using 2,2-diphenyl-1-picrylhydrazyl (DPPH radical. All the whey fractions showed radical scavenging activities. The five isolates with the highest activities were selected. On the basis of Gram stain reaction, cellular morphology, biochemical tests and carbohydrate utilization profiles they were identified as strains of Lactobacillus brevis, L. fermentum, L. plantarum, L. casei and L. delbrueckii. The antioxidant activities of whey fractions from 24-hour fermentations with the selected organisms were investigated using both radical scavenging effects and lipid peroxidation inhibitory activity. The radical scavenging activity was generally higher than the lipid peroxidation inhibition, except in the L. plantarum strain, which did not show any significant difference in both activities. The probiotic potential of the isolates was evaluated by pH and bile tolerance. None of the selected isolates showed any growth at pH=2.0 but L. casei and L. delbrueckii survived at this pH. Four of the five selected isolates were able to grow in 0.5 % dehydrated bile, with L. casei strain showing the highest level of growth, followed by L. delbrueckii. L. plantarum strain was not bile tolerant. The ability of L. casei and L. delbrueckii strains to survive at pH=2 and grow in the presence of bile indicates that the isolates may be able to colonize the gastrointestinal tract. The findings of this study indicate that Lactobacillus strains isolated from indigenous Nigerian fermented foods could be useful as starter cultures to provide antioxidants in food and that fermented milk

Age-related associative deficits and the isolation effect.

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Badham, Stephen P; Maylor, Elizabeth A

2013-01-01

If all but one of the items in a list are similar (e.g., all black except one red), memory for the different item is enhanced (the isolation effect). Older adults generally show similar or smaller isolation effects compared to young adults, which has been attributed to age-related deficits in associative memory whereby older adults are less able to associate an isolated stimulus to its isolating feature. Experiment 1 examined the isolation effect for isolation based on spatial position, modality and color; in Experiment 2, the criterion for isolation was the associative relation between stimuli. The results consistently showed no differences between young and older participants in the magnitude of the isolation effect. Whilst age deficits in associative memory may act to reduce the isolation effect in older adults, age deficits in self-initiated processing and inhibitory functionality may counteract this reduction by enhancing the isolation effect in older adults.

Investigation of the Antimicrobial Activity of Bacillus licheniformis Strains Isolated from Retail Powdered Infant Milk Formulae.

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Alvarez-Ordóñez, Avelino; Begley, Máire; Clifford, Tanya; Deasy, Thérèse; Considine, Kiera; O'Connor, Paula; Ross, R Paul; Hill, Colin

2014-03-01

This study investigated the potential antimicrobial activity of ten Bacillus licheniformis strains isolated from retail infant milk formulae against a range of indicator (Lactococcus lactis, Lactobacillus bulgaricus and Listeria innocua) and clinically relevant (Listeria monocytogenes, Staphylococcus aureus, Streptococcus agalactiae, Salmonella Typhimurium and Escherichia coli) microorganisms. Deferred antagonism assays confirmed that all B. licheniformis isolates show antimicrobial activity against the Gram-positive target organisms. PCR and matrix-assisted laser desorption ionization time-of-flight mass spectrometry analyses indicated that four of the B. licheniformis isolates produce the bacteriocin lichenicidin. The remaining six isolates demonstrated a higher antimicrobial potency than lichenicidin-producing strains. Further analyses identified a peptide of ~1,422 Da as the most likely bioactive responsible for the antibacterial activity of these six isolates. N-terminal sequencing of the ~1,422 Da peptide from one strain identified it as ILPEITXIFHD. This peptide shows a high homology to the non-ribosomal peptides bacitracin and subpeptin, known to be produced by Bacillus spp. Subsequent PCR analyses demonstrated that the six B. licheniformis isolates may harbor the genetic machinery needed for the synthesis of a non-ribosomal peptide synthetase similar to those involved in production of subpeptin and bacitracin, which suggests that the ~1,422 Da peptide might be a variant of subpeptin and bacitracin.

Characteristics of enterotoxin distribution, hemolysis, lecithinase, and starch hydrolysis of Bacillus cereus isolated from infant formulas and ready-to-eat foods.

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Hwang, Ji-Yeon; Park, Jong-Hyun

2015-03-01

Bacillus cereus is a ubiquitous environmental microbe implicated as a main cause of food poisoning with various symptoms, depending on the strain type and the isolation source. In this study, the potential virulence factors and biochemical properties of B. cereus isolated from infant formulas and ready-to-eat (RTE) foods were analyzed and compared. A total of 347 B. cereus strains were isolated and identified from 687 infant food formulas and RTE food samples. All the isolates had one or more enterotoxin genes, and one-half of the strains had all 3 enterotoxin genes (hbl, nhe, and cytK) that are involved in food poisoning in humans. Here, all the 3 genes were detected in 50% of the B. cereus isolates from RTE foods and only 14% of the isolates were identified from infant formulas. The latter harbored low cytK and bceT, and very low hbl genes. Most B. cereus isolates possessed the hemolysis gene, but not the ces gene. The infant formula isolates showed stronger hemolysis activity than the other isolates. In addition, 26% of the total isolates showed low lecithinase activities and 10% showed high lecithinase activities. A greater number of isolates from the infant formula showed high lecithinase activity than those from the RTE foods. Approximately 83% of the isolates were positive and 17% were negative for starch hydrolysis. Over 90% of the RTE food isolates and only 35% of the infant formula isolates were positive for starch hydrolysis. However, all the strains possessed nhe, but their harboring patterns of hbl and cytK were significantly different. Most starch-hydrolyzing strains possessed hbl, but only 23% nonstarch-hydrolyzing isolates possessed this gene. Moreover, very low nonstarch hydrolyzing strains harbored cytK. Most nonstarch-hydrolyzing isolates showed high lecithinase and strong hemolysis activities, and very low hbl and cytK harboring. In summary, most infant formula isolates showed stronger hemolysis and higher lecithinase activities with lower

Marine fungi isolated from Chilean fjord sediments can degrade oxytetracycline.

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Ahumada-Rudolph, R; Novoa, V; Sáez, K; Martínez, M; Rudolph, A; Torres-Diaz, C; Becerra, J

2016-08-01

Salmon farming is the main economic activity in the fjords area of Southern Chile. This activity requires the use of antibiotics, such as oxytetracycline, for the control and prevention of diseases, which have a negative impact on the environment. We analyzed the abilities of endemic marine fungi to biodegrade oxytetracycline, an antibiotic used extensively in fish farming. We isolated marine fungi strains from sediment samples obtained from an area of fish farming activity. The five isolated strains showed an activity on oxytetracycline and were identified as Trichoderma harzianum, Trichoderma deliquescens, Penicillium crustosum, Rhodotorula mucilaginosa, and Talaromyces atroroseus by a scanning electron microscopy and characterized by molecular techniques. Results showed significant degradation in the concentration of oxytetracycline at the first 2 days of treatment for all strains analyzed. At 21 days of treatment, the concentration of oxytetracycline was decreased 92 % by T. harzianum, 85 % by T. deliquescens, 83 % by P. crustosum, 73 % by R. mucilaginosa, and 72 % by T. atroroseus, all of which were significantly higher than the controls. Given these results, we propose that fungal strains isolated from marine sediments may be useful tools for biodegradation of antibiotics, such as oxytetracycline, in the salmon industry.

Characterization of ESBL-producing Escherichia coli and Klebsiella pneumoniae strains isolated from urine of nonhospitalized patients in the Zagreb region

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Branka Bedenić,

2010-02-01

Full Text Available Aim To determine the prevalence of ESBL-producing Escherichia coli and Klebsiella pneumoniae strains isolated from urine of nonhospitalized patients during a three-year period, to determine their antibiotic susceptibility, investigate the transfer of ESBL genes with cotransfer of resistance and to characterize isolated beta-lactamases. Methods Antimicrobial susceptibility was determined by disk diffusion and broth microdilution methods. The double-disk test was used for ESBL detection. Transfer of resistance was performed by broth mating method and characterization of isolated beta-lactamases by polymerase chain reaction. Results The prevalence of ESBL-producing E. coli was 1.5% and of K. pneumoniae 4.1% with its different distribution according to patients`age and gender. ESBL-producing K. pneumoniae showed high resistance rates to aminoglycosides, cotrimoxazole, nitrofurantoin and quinolones while ESBL-producing E. coli isolates, with exception of high aminoglycoside resistance, showed low resistance rates to other antibiotics. Successful conjugation of ESBL genes was obtained with 25% E. coli and 76.2% K. pneumoniae strains. Comparing to E. coli, K. pneumoniae strains showed higher rates of aminoglycosideand cotrimoxazole resistance cotransfer. Beta-lactamases of investigated strains belonged to TEM, SHV and CTX-M families.Conclusion The existence of multiple-resistant ESBL-producing E. coli and K. pneumoniae strains was confirmed in observed outpatient population. ESBL-producing K. pneumoniae isolates, in contrast toESBL-producing E. coli, showed higher resistance rates to non-beta-lactam antibiotics, probably caused by cotransfer of resistance genes located on the same plasmid as ESBL genes. It is important to monitor the prevalence of such strains and their possible spreading in the outpatient population of the Zagreb region

Isolation, Identification, and Evaluation of Novel Probiotic Strains Isolated from Feces of Breast-Fed Infants.

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Panya, Marutpong; Lulitanond, Viraphong; Rattanachaikunsopon, Pongsak; Srivoramas, Thanyakarn; Chaiwong, Tarinee

2016-01-01

To isolate, identify, and evaluate the probiotic properties of lactic acid bacteria (LAB) isolated from the feces of breast-fed infants. The probiotic tests included investigation of hemolysis activity, survival in simulated gastrointestinal tract conditions (acid and bile salt tolerance), susceptibility to antibiotics, and ability to inhibit selected bacterial pathogens (Escherichia coli O157:H7, Vibrio cholerae and Salmonella enterica subsp enterica serovar Typhimurium). The bacterial species identification was performed by both carbohydrate utilization and partial 16S ribosomal RNA sequencing. Five of fifty LAB isolates (UBU-03, UBU-06, UBU-09, UBU-34, and UBU-37) showed good probiotic properties. These five isolates showed non-hemolysis type (gamma-hemolysis), susceptibility to all antibiotics tested except for vancomycin, ability to survive in the simulated gastrointestinal conditions of both acid and bile salt solution, and ability to inhibit growth of E. coli O157: H7 and V. cholerae. Bacterial species identification revealed that all five isolates were firmly identified as Lactobacillus rhamnosus species. The L. rhamnosus strains that were isolated and characterized in this study could be considered as probiotic strains, and then used for further probiotic characterization in human cell cultures or animal models.

Slime production and antibiotic susceptibility in staphylococci isolated from clinical samples

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Seza Arslan

2007-02-01

Full Text Available A total of 187 isolates from several clinical specimens were identified to species level as 129 Staphylococcus aureus strains and 58 coagulase-negative staphylococci (CNS strains by the API Staph System (Biomerieux. Slime production was detected both by the conventional Christensen's method as well as by the Congo red agar method. Seventy-two strains of staphylococci isolates (38.5% were found to be slime producers by Christensen's test tube method whereas 58 strains (31% were slime positive with Congo red agar method. There was no statistically significant difference between the two methods for the detection of slime production (P > 0.05. Susceptibility of isolates against antimicrobial agents was tested by the disk diffusion method. Staphylococcal species had resistance to one or more antibiotics. Among the various antimicrobial agents, oxacillin (71.1% and erythromycin (47.1% showed higher resistance than most of the agents used against all isolates. Oxacillin resistant S. aureus (ORSA and oxacillin resistant coagulase-negative staphylococci (ORCNS, 97 (75.2% and 36 (62.1% respectively were frequently observed in strains isolated from clinical materials. Among the ORSA strains, two strains were resistant to vancomycin. Moreover, 96 (74.4% of 129 S. aureus strains were positive for blactamase enzyme. However, 78 (81.25% of 96 b-lactamase positive S. aureus strains were b-lactamase positive ORSA isolates, but none of them had vancomycin resistance.

Production of cellulases by fungal cultures isolated from forest litter soil

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A. Sri Lakshmi

2012-06-01

Full Text Available The aims of this study were the isolation and screening of fungal cultures from forest litter soil for cellulases production. In the present study, four fungal cultures were isolated and identified. Among these fungal cultures, three belonged to the genus Aspergillus and one belonged to the genus Pencillium. These fungal cultures were tested to find their ability to produce cellulases, that catalyze the degradation of cellulose, which is a linear polymer made of glucose subunits linked by beta-1, 4 glycosidic bonds. The fungal isolate 3 (Aspergillus sp. was noticed to show maximum zone of hydrolysis of carboxy-methyl cellulose and produce higher titers of cellulases including exoglucanase, endoglucanase and beta -D-glucosidase. The activities of the cellulases were determined by Filter paper assay (FPA, Carboxy-methly cellulase assay (CMCase and beta -D-glucosidase assay respectively. The total soluble sugar and extracellular protein contents of the fungal filtrates were also determined.

Antimicrobial Susceptibility of Bordetella bronchiseptica Isolates from Swine and Companion Animals and Detection of Resistance Genes.

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Sandra Prüller

Full Text Available Bordetella bronchiseptica causes infections of the respiratory tract in swine and other mammals and is a precursor for secondary infections with Pasteurella multocida. Treatment of B. bronchiseptica infections is conducted primarily with antimicrobial agents. Therefore it is essential to get an overview of the susceptibility status of these bacteria. The aim of this study was to comparatively analyse broth microdilution susceptibility testing according to CLSI recommendations with an incubation time of 16 to 20 hours and a longer incubation time of 24 hours, as recently proposed to obtain more homogenous MICs. Susceptibility testing against a panel of 22 antimicrobial agents and two fixed combinations was performed with 107 porcine isolates from different farms and regions in Germany and 43 isolates obtained from companion animals in Germany and other European countries. Isolates with increased MICs were investigated by PCR assays for the presence of resistance genes. For ampicillin, all 107 porcine isolates were classified as resistant, whereas only a single isolate was resistant to florfenicol. All isolates obtained from companion animals showed elevated MICs for β-lactam antibiotics and demonstrated an overall low susceptibility to cephalosporines. Extension of the incubation time resulted in 1-2 dilution steps higher MIC50 values of porcine isolates for seven antimicrobial agents tested, while isolates from companion animals exhibited twofold higher MIC50/90 values only for tetracycline and cefotaxime. For three antimicrobial agents, lower MIC50 and MIC90 values were detected for both, porcine and companion animal isolates. Among the 150 isolates tested, the resistance genes blaBOR-1 (n = 147, blaOXA-2, (n = 4, strA and strB (n = 17, sul1 (n = 10, sul2 (n = 73, dfrA7 (n = 3 and tet(A (n = 8 were detected and a plasmid localisation was identified for several of the resistance genes.

Efficacy of Metarhizium anisopliae isolate MAX-2 from Shangri-la, China under desiccation stress

Science.gov (United States)

2014-01-01

Background Metarhizium anisopliae, a soil-borne entomopathogen found worldwide, is an interesting fungus for biological control. However, its efficacy in the fields is significantly affected by environmental conditions, particularly moisture. To overcome the weakness of Metarhizium and determine its isolates with antistress capacity, the efficacies of four M. anisopliae isolates, which were collected from arid regions of Yunnan Province in China during the dry season, were determined at different moisture levels, and the efficacy of the isolate MAX-2 from Shangri-la under desiccation stress was evaluated at low moisture level. Results M. anisopliae isolates MAX-2, MAC-6, MAL-1, and MAQ-28 showed gradient descent efficacies against sterile Tenebrio molitor larvae, and gradient descent capacities against desiccation with the decrease in moisture levels. The efficacy of MAX-2 showed no significant differences at 35% moisture level than those of the other isolates. However, significant differences were found at 8% to 30% moisture levels. The efficacies of all isolates decreased with the decrease in moisture levels. MAX-2 was relatively less affected by desiccation stress. Its efficacy was almost unaffected by the decrease at moisture levels > 25%, but slowly decreased at moisture levels molitor larvae under desiccation stress and in wet microhabitat. Local black patches were found on the cuticles of the insects, and the cadavers dried without fungal growth under desiccation stress. However, dark black internodes and fungal growth were found after death of the insects in the wet microhabitat. Conclusions MAX-2 showed significantly higher efficacy and superior antistress capacity than the other isolates under desiccation stress. The infection of sterile T. molitor larvae at low moisture level constituted a valid laboratory bioassay system in evaluating M. anisopliae efficacy under desiccation stress. PMID:24383424

Efficacy of Metarhizium anisopliae isolate MAX-2 from Shangri-la, China under desiccation stress.

Science.gov (United States)

Chen, Zi-Hong; Xu, Ling; Yang, Feng-lian; Ji, Guang-Hai; Yang, Jing; Wang, Jian-Yun

2014-01-03

Metarhizium anisopliae, a soil-borne entomopathogen found worldwide, is an interesting fungus for biological control. However, its efficacy in the fields is significantly affected by environmental conditions, particularly moisture. To overcome the weakness of Metarhizium and determine its isolates with antistress capacity, the efficacies of four M. anisopliae isolates, which were collected from arid regions of Yunnan Province in China during the dry season, were determined at different moisture levels, and the efficacy of the isolate MAX-2 from Shangri-la under desiccation stress was evaluated at low moisture level. M. anisopliae isolates MAX-2, MAC-6, MAL-1, and MAQ-28 showed gradient descent efficacies against sterile Tenebrio molitor larvae, and gradient descent capacities against desiccation with the decrease in moisture levels. The efficacy of MAX-2 showed no significant differences at 35% moisture level than those of the other isolates. However, significant differences were found at 8% to 30% moisture levels. The efficacies of all isolates decreased with the decrease in moisture levels. MAX-2 was relatively less affected by desiccation stress. Its efficacy was almost unaffected by the decrease at moisture levels > 25%, but slowly decreased at moisture levels molitor larvae under desiccation stress and in wet microhabitat. Local black patches were found on the cuticles of the insects, and the cadavers dried without fungal growth under desiccation stress. However, dark black internodes and fungal growth were found after death of the insects in the wet microhabitat. MAX-2 showed significantly higher efficacy and superior antistress capacity than the other isolates under desiccation stress. The infection of sterile T. molitor larvae at low moisture level constituted a valid laboratory bioassay system in evaluating M. anisopliae efficacy under desiccation stress.

Correlates of Objective Social Isolation from Family and Friends among Older Adults.

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Chatters, Linda M; Taylor, Harry Owen; Nicklett, Emily J; Taylor, Robert Joseph

2018-03-03

This study examined the correlates of objective social isolation from extended family members and friends among older adults. The analysis is based on the older adult sub-sample of the National Survey of American Life ( n = 1321). Multinomial logistic regression analyses examined race/ethnicity, demographics, functional health and family and friend network factors as correlates of objective isolation from family and friends. Only 4.47% of respondents were objectively isolated from both their extended family and friends, 10.82% were isolated from their friends, and 7.43% were isolated from their family members. Men were more likely to be objectively isolated from both family and friends and older adults who live with others were significantly more likely to be objectively isolated from their friends. When controlling for subjective social isolation, the two measures of functional health were significantly associated with objective social isolation. In particular, higher levels of self-care impairment decreased the risk of being objectively isolated from friends only, whereas higher mobility impairment was associated with an increased likelihood of being objectively isolated from friends only. Subjective evaluations of social isolation from family and friends were consistently associated with being objectively isolated from family and friends. There were no significant differences between African-Americans, Black Caribbeans and non-Hispanic Whites in objective isolation. These and other findings are discussed in detail.

Correlates of Objective Social Isolation from Family and Friends among Older Adults

Science.gov (United States)

Chatters, Linda M.; Taylor, Harry Owen; Taylor, Robert Joseph

2018-01-01

This study examined the correlates of objective social isolation from extended family members and friends among older adults. The analysis is based on the older adult sub-sample of the National Survey of American Life (n = 1321). Multinomial logistic regression analyses examined race/ethnicity, demographics, functional health and family and friend network factors as correlates of objective isolation from family and friends. Only 4.47% of respondents were objectively isolated from both their extended family and friends, 10.82% were isolated from their friends, and 7.43% were isolated from their family members. Men were more likely to be objectively isolated from both family and friends and older adults who live with others were significantly more likely to be objectively isolated from their friends. When controlling for subjective social isolation, the two measures of functional health were significantly associated with objective social isolation. In particular, higher levels of self-care impairment decreased the risk of being objectively isolated from friends only, whereas higher mobility impairment was associated with an increased likelihood of being objectively isolated from friends only. Subjective evaluations of social isolation from family and friends were consistently associated with being objectively isolated from family and friends. There were no significant differences between African-Americans, Black Caribbeans and non-Hispanic Whites in objective isolation. These and other findings are discussed in detail. PMID:29510504

Antifungal Activity of Bee Venom and Sweet Bee Venom against Clinically Isolated Candida albicans

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Seung-Bae Lee

2016-03-01

Full Text Available Objectives: The purpose of this study was to investigate the antifungal effect of bee venom (BV and sweet bee venom (SBV against Candida albicans (C. albicans clinical isolates. Methods: In this study, BV and SBV were examined for antifungal activities against the Korean Collection for Type Cultures (KCTC strain and 10 clinical isolates of C. albicans. The disk diffusion method was used to measure the antifungal activity and minimum inhibitory concentration (MIC assays were performed by using a broth microdilution method. Also, a killing curve assay was conducted to investigate the kinetics of the anti- fungal action. Results: BV and SBV showed antifungal activity against 10 clinical isolates of C. albicans that were cultured from blood and the vagina by using disk diffusion method. The MIC values obtained for clinical isolates by using the broth microdilution method varied from 62.5 μg/ mL to 125 μg/mL for BV and from 15.63 μg/mL to 62.5 μg/mL for SBV. In the killing-curve assay, SBV behaved as amphotericin B, which was used as positive control, did. The antifungal efficacy of SBV was much higher than that of BV. Conclusion: BV and SBV showed antifungal activity against C. albicans clinical strains that were isolated from blood and the vagina. Especially, SBV might be a candidate for a new antifungal agent against C. albicans clinical isolates.

Bioremediation capability and characterization of bacteria isolated from petroleum contaminated soils in Iran

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Golafarin Ghoreishi

2017-07-01

Full Text Available This study was carried out to isolate bacteria for bioremediation of petroleum polluted soils. Five samples were used for isolation in this study. They were four soil samples in addition to one kerosene sample. The soil samples including soils contaminated by crude oil and gas oil and two soil samples with no outward contamination which were collected from Shiraz Oil Refinery sites. Seven strains were selected among the isolated colonies for further experiments. The selected isolates were cultured in standard succinate medium (SSM minimal medium in which 2.5% v/v kerosene was used as carbon source. In another bacterial SSM culture, carbon, sulfur or nitrogen source was removed and 20% v/v kerosene added to check the ability of isolates to utilizekerosene as sole source for C, N and S. Finally, cultures of four strains with higher growth in modified SSM cultures were selected for GC analysis. In this study they were named C2 and C4 which were isolated from crude oil contaminated soil and SI1 and SI2 isolated from soils with no outward contamination. GC analysis showed that C2 could degrade 69% of 5% v/v kerosene in 7 d, while C4 and SI1 degraded 48% and 42% of 5% v/v kerosene during this 7-d period respectively, and the degradation ability of SI2 was 38% after 7 d. Analysis of 16S rRNA gene showed that C2 was close to Citrobacter sedlakii, C4 and SI1 were related to Entrobacter hormeachei and SI2 was close to Entrobacter cloacae, respectively.

In vitro antimicrobial activity of extracts and isolated compound from Dalbergia stipulacea Roxb. leaves

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Kumar, Arvind; Bhat, Tahir Ahmad; Singh, Rattan Deep

2017-07-01

The study was designed to examine the in vitro antimicrobial efficacy of extracts and isolated compound of Dalbergia stipulacea. Combined extracts (chloroform and methanol) of plant leaves fractionated with n-butanol loaded with column afforded a flavonoid glycoside compound identified as luteolin 4'-rutinoside. Different extracts and isolated compound exhibited pronounced antibacterial and antifungal varied activities against four bacteria (Clostridium acetobutylinium, Bacillus subtilis, Streptococcus mutans, and Pseudomonas sp.) and one fungus (Candida albicans) susceptibility were determined using disc diffusion method. The minimum inhibitory concentration (MIC) of extracts and isolated compounds was determined by broth dilution method. The maximum activity was shown by chloroform extract against C. albicans with a zone of inhibition of 17 mm and minimum activity was displayed by methanolic extract against Pseudomonas sp. with 5 mm. However, isolated compound has shown maximum activity against Pseudomonas sp. with 15 mm. The MIC values higher in methanol extract against Pseudomonas sp. and isolated compound shows good against Pseudomonas sp. and B. subtilis. Our findings indicate that plant could be used as a good antimicrobial agent in food, pharmaceutical and bio-pesticide industries.

Antimicrobial Agent of Susceptibilities and Antiseptic Resistance Gene Distribution among Methicillin-Resistant Staphylococcus aureus Isolates from Patients with Impetigo and Staphylococcal Scalded Skin Syndrome

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Noguchi, Norihisa; Nakaminami, Hidemasa; Nishijima, Setsuko; Kurokawa, Ichiro; So, Hiromu; Sasatsu, Masanori

2006-01-01

The susceptibilities to antimicrobial agents of and distributions of antiseptic resistance genes in methicillin-resistant Staphylococcus aureus (MRSA) strains isolated between 1999 and 2004 in Japan were examined. The data of MRSA strains that are causative agents of impetigo and staphylococcal scalded skin syndrome (SSSS) were compared with those of MRSA strains isolated from patients with other diseases. The susceptibilities to antiseptic agents in MRSA isolates from patients with impetigo and SSSS were higher than those in MRSA isolates from patients with other diseases. The distribution of the qacA/B genes in MRSA strains isolated from patients with impetigo and SSSS (1.3%, 1/76) was remarkably lower than that in MRSA strains isolated from patients with other diseases (45.9%, 95/207). Epidemiologic typings of staphylococcal cassette chromosome mec (SCCmec) and pulsed-field gel electrophoresis (PFGE) showed that MRSA strains isolated from patients with impetigo and SSSS had type IV SCCmec (75/76), except for one strain, and 64.5% (49/76) of the strains had different PFGE types. In addition, the patterns of restriction digestion of all tested qacA/B plasmid in MRSA isolates having different PFGE types were identical. The results showed that a specific MRSA clone carrying qacA/B was not prevalent, but qacA/B was spread among health care-associated MRSA strains. Therefore, it was concluded that the lower distribution rate of qacA/B resulted in higher susceptibilities to cationic antiseptic agents in MRSA isolated from patients with impetigo and SSSS. PMID:16757607

Potential Antioxidant Anthraquinones Isolated from Rheum emodi Showing Nematicidal Activity against Meloidogyne incognita

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Brijesh Tripathi

2014-01-01

Full Text Available Antioxidant and nematicidal properties were evaluated for R. emodi extractives which are extracted by standardizing and adopting accelerated solvent extraction (ASE method along with traditional Soxhlet extraction. The extracted material was separated using flash chromatography and the separation conditions and solvents were standardized for the extracted plant constituents. The purity was detected by using analytical reverse phase high pressure liquid chromatography (HPLC. LC-MS/MS detection in the direct infusion mode of the isolated, purified products afforded four anthraquinones, characterized by their infrared spectra (IR and 1H spectra as chrysophanol, physcion, emodin, and aloe-emodin. Five antraquinone glucoside derivatives and piceatannol-3-O-β-d-glucopyranoside have also been detected from the extracted product. During in vitro evaluation the antioxidant potential of methanolic crude extract (CE1 was the highest, followed by ethyl acetate crude extract (CE2 and chloroform extract (CE3 in DPPH radical scavenging activity. The CE1 also demonstrated outstanding nematicidal activity as compared with other extracts, pure anthraquinones, and even positive control azadirachtin. The study conclusively demonstrated the antioxidant potential of R. emodi extracts and also its ability in extenuating the Meloidogyne incognita (root-knot nematode. The bioassay results can be extrapolated to actual field condition and clinical studies.

Chlorine-containing natural compounds in higher plants

DEFF Research Database (Denmark)

Engvild, Kjeld Christensen

1986-01-01

More than 130 chlorine-containing compounds have been isolated from higher plants and ferns; about half are polyacetylenes, thiophenes and sesquiterpene lactones from the Asteraceae. A chlorinated chlorophyll may be an important part of photosystem 1. High biological activity is found in 4...

Isolation of Antagonistic Endophytes from Banana Roots against Meloidogyne javanica and Their Effects on Soil Nematode Community

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Lanxi Su

2017-10-01

Full Text Available Banana production is seriously hindered by Meloidogyne spp. all over the world. Endophytes are ideal candidates compared to pesticides as an environmentally benign agent. In the present study, endophytes isolated from banana roots infected by Meloidogyne spp. with different disease levels were tested in vitro, and in sterile and nature banana monoculture soils against Meloidogyne javanica. The proportion of antagonistic endophytes were higher in the roots of middle and high disease levels. Among those, bacteria were dominant, and Pseudomonas spp., Bacillus spp. and Streptomyces spp. showed more abundant populations. One strain, named as SA, with definite root inner-colonization ability was isolated and identified as Streptomyces sp. This strain showed an inhibiting rate of >50% in vitro and biocontrol efficiency of 70.7% in sterile soil against Meloidogyne javanica, compared to the control. Greenhouse experiment results showed that the strain SA exhibits excellent biological control ability for plant-parasites both in roots and in root-knot nematode infested soil. SA treatment showed a higher number of bacterivores, especially Mesorhabditis and Cephalobus. The maturity index was significantly lower, while enrichment index (EI was significantly higher in the SA treatment. In conclusion, this study presents an important potential application of the endophytic strain Streptomyces sp. for the control of plant-parasitic nematodes, especially Meloidogyne javanica, and presents the effects on the associated variation of the nematode community.

K. OXYTOCA BACTERIOPHAGES ISOLATION METHODS IMPROVEMENT

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G. R. Sadrtdinova

2017-01-01

Full Text Available The article presents the results of a study related to increasing the efficiency of phage isolation of bacteria of the species K. oxytoca, by developing the optimal composition of the medium used in the work. In scientific research, in almost all methods associated with the isolation of bacteriophages, meat-peptone broth and meat-peptone agar are used as the nutrient basis. The peculiarities of growth and cultivation of microorganisms create certain difficulties for the isolation of phages active against bacteria of the species K. oxytoca. The selection of components and the creation of an environment that would ensure the optimal growth of both the bacterial culture and the reproduction of the virus makes it possible to facilitate the isolation of bacteriophages. The number of bacterial strains used in the work was 7. All strains of cultures were obtained from the Museum of the Department of Microbiology, Virology, Epizootology and Veterinary and Sanitary Expertise of the Federal State Budget Educational Institution of Higher Education “Ulyanovsk State Agrarian University named after P.A. Stolypin”. The studies included 2 main stages. The first stage consisted in isolation of bacteriophages by the method of isolation from the external environment by the method of Adelson L.I., Lyashenko E.A. The material for the studies were samples: soil, sewage sample, fecal samples (2. Only 4 samples. According to the chosen method, the sowing of the putative phagolysate was carried out on meat-peptone agar (1.5% and the agar for isolating bacteriophages (Aph (1.5%. A positive result was the presence on the environment of negative colonies, clearly visible on the matt background of deep growth of bacteria. A negative result is a continuous growth (“lawn” of bacterial culture. As a control, the culture of the microorganism studied was used for the media. In the course of the conducted studies for the first stage, 2 bacteriophages were isolated, active

Reciprocal Hosts' Responses to Powdery Mildew Isolates Originating from Domesticated Wheats and Their Wild Progenitor.

Science.gov (United States)

Ben-David, Roi; Dinoor, Amos; Peleg, Zvi; Fahima, Tzion

2018-01-01

The biotroph wheat powdery mildew, Blumeria graminis (DC.) E.O. Speer, f. sp. tritici Em. Marchal ( Bgt ), has undergone long and dynamic co-evolution with its hosts. In the last 10,000 years, processes involved in plant evolution under domestication, altered host-population structure. Recently both virulence and genomic profiling separated Bgt into two groups based on their origin from domestic host and from wild emmer wheat. While most studies focused on the Bgt pathogen, there is significant knowledge gaps in the role of wheat host diversity in this specification. This study aimed to fill this gap by exploring qualitatively and also quantitatively the disease response of diverse host panel to powdery mildew [105 domesticated wheat genotypes ( Triticum turgidum ssp. dicoccum, T. turgidum ssp. durum , and T. aestivum ) and 241 accessions of its direct progenitor, wild emmer wheat ( T. turgidum ssp. dicoccoides )]. A set of eight Bgt isolates, originally collected from domesticated and wild wheat was used for screening this wheat collection. The isolates from domesticated wheat elicited susceptible to moderate plant responses on domesticated wheat lines and high resistance on wild genotypes (51.7% of the tested lines were resistant). Isolates from wild emmer elicited reciprocal disease responses: high resistance of domesticated germplasm and high susceptibility of the wild material (their original host). Analysis of variance of the quantitative phenotypic responses showed a significant Isolates × Host species interaction [ P (F) < 0.0001] and further supported these findings. Furthermore, analysis of the range of disease severity values showed that when the group of host genotypes was inoculated with Bgt isolate from the reciprocal host, coefficient of variation was significantly higher than when inoculated with its own isolates. This trend was attributed to the role of major resistance genes in the latter scenario (high proportion of complete resistance). By

Reciprocal Hosts' Responses to Powdery Mildew Isolates Originating from Domesticated Wheats and Their Wild Progenitor

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Roi Ben-David

2018-02-01

Full Text Available The biotroph wheat powdery mildew, Blumeria graminis (DC. E.O. Speer, f. sp. tritici Em. Marchal (Bgt, has undergone long and dynamic co-evolution with its hosts. In the last 10,000 years, processes involved in plant evolution under domestication, altered host-population structure. Recently both virulence and genomic profiling separated Bgt into two groups based on their origin from domestic host and from wild emmer wheat. While most studies focused on the Bgt pathogen, there is significant knowledge gaps in the role of wheat host diversity in this specification. This study aimed to fill this gap by exploring qualitatively and also quantitatively the disease response of diverse host panel to powdery mildew [105 domesticated wheat genotypes (Triticum turgidum ssp. dicoccum, T. turgidum ssp. durum, and T. aestivum and 241 accessions of its direct progenitor, wild emmer wheat (T. turgidum ssp. dicoccoides]. A set of eight Bgt isolates, originally collected from domesticated and wild wheat was used for screening this wheat collection. The isolates from domesticated wheat elicited susceptible to moderate plant responses on domesticated wheat lines and high resistance on wild genotypes (51.7% of the tested lines were resistant. Isolates from wild emmer elicited reciprocal disease responses: high resistance of domesticated germplasm and high susceptibility of the wild material (their original host. Analysis of variance of the quantitative phenotypic responses showed a significant Isolates × Host species interaction [P(F < 0.0001] and further supported these findings. Furthermore, analysis of the range of disease severity values showed that when the group of host genotypes was inoculated with Bgt isolate from the reciprocal host, coefficient of variation was significantly higher than when inoculated with its own isolates. This trend was attributed to the role of major resistance genes in the latter scenario (high proportion of complete resistance. By

Candida species isolated from the vaginal mucosa of HIV-infected women in Salvador, Bahia, Brazil

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Paula Matos Oliveira

Full Text Available BACKGROUND: Vulvovaginal candidiasis (VVC is the second most common vaginal infection. HIV-infection is a risk factor for this infection. OBJECTIVE: To determine the frequency of VVC and to describe the main Candida species isolated and their susceptibility to antifungal drugs in HIV-infected patients, compared to HIV-uninfected women in Salvador, Brazil. METHODS: Cross-sectional study including a group of 64 HIV-infected women and 76 uninfected women, followed up at the AIDS reference center and at the Gynecological Clinic of Escola Bahiana de Medicina e Saúde Pública (Salvador, Bahia, Brazil. RESULTS: Frequency of Candida spp. was higher in HIV-infected women (29.7% than in HIV-uninfected controls (14.5% (p = 0.02. The odds ratio value for vulvovaginal candidiasis in HIV-infected patients was 2.6 (95% CI: 1.07 - 6.32 p = 0.03. Candida albicans was the most commonly isolated species in both HIV-infected (52.3% and uninfected women (85.7%, followed by C. parapsolis in 17.6% and 14.3%, respectively. In HIV-infected women, C. glabrata, C. parapsilosis, and a coinfection of C. albicans and C. glabrata were also identified. There was no significant difference between Candida species isolated from the vaginal mucosa of women with VVC and colonization of the vaginal mucosa of HIV-infected and HIV-uninfected women. One C. glabrata isolate from an HIV-infected patient was resistant to fluconazole and other two isolates exhibited a dose-dependent susceptibility. CONCLUSION: Our results confirm a higher frequency of Candida spp. isolated from the vaginal mucosa of HIV-infected women and a broader spectrum of species involved. Only Candida glabrata isolates showed decreased susceptibility to fluconazole.

Isolated optic nerve pseudotumour

International Nuclear Information System (INIS)

Patankar, T.; Prasad, S.; Krishnan, A.; Laxminarayan, R.

2000-01-01

Isolated optic nerve involvement by the idiopathic inflammatory process is a rare finding and very few reports are available. Here a case of an isolated optic nerve inflammatory pseudotumour presenting with gradually progressive unilateral loss of vision is described. It showed dramatic response to a trial of steroids and its differential diagnoses are discussed. Copyright (1999) Blackwell Science Pty Ltd

Frequency of antiseptic resistance genes in clinical staphycocci and enterococci isolates in Turkey

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Seyda Ignak

2017-08-01

Full Text Available Abstract Background Disinfectants and antiseptics are biocides widely used in hospitals to prevent spread of pathogens. It has been reported that antiseptic resistance genes, qac’s, caused tolerance to a variety of biocidal agents, such as benzalkonium chloride (BAC and chlorhexidine digluconate (CHDG in Staphylococcus spp. isolates. We aimed to search the frequency of antiseptic resistance genes in clinical Staphylococcus spp. and Enterococcus spp. isolates to investigate the possible association with antiseptic tolerance and antibiotic resistance. Methods Antiseptic resistance genes (qacA/B, smr, qacG, qacH, and qacJ isolated from Gram-positive cocci (69 Staphylococcus spp. and 69 Enterococcus spp. were analyzed by PCR method. The minimum inhibitory concentrations (MICs of BAC and CHDG were determined by agar dilution method, whereas antibiotic susceptibility was analyzed by disk diffusion method according to Clinical and Laboratory Standards Institute (CLSI criteria. Results The frequency of antiseptic resistance genes was found to be high (49/69; 71.0% in our clinical staphylococci isolates but absent (0/69; 0% in enterococci isolates. The frequency of qacA/B and smr genes was higher (25/40; 62.5% and 7/40; 17.5%, respectively in coagulase negative staphylococci (CNS when compared to Staphylococcus aureus strains (3/29; 10.3%, and 4/29; 13.8%, respectively. In contrast, the frequency of qacG and qacJ genes was higher (11/29; 37.9% and 8/29; 27.5%, respectively in S. aureus than those of CNS (5/40; 12.5%, 10/40; 25.0% strains. qacH was not identified in none of the strains. We found an association between presence of antiseptic resistance genes and increased MIC values of BAC (>4 μg/mL in staphylococci and it was found to be statistically statistically significant (p < 0.01. We also showed that MICs of BAC and CHDG of vancomycin-resistant enterococci (VRE isolates were significantly higher than those of vancomycin

CFT/gravity correspondence on the isolated horizon

Energy Technology Data Exchange (ETDEWEB)

Ghosh, Amit, E-mail: amit.ghosh@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, 700064 Kolkata (India); Pranzetti, Daniele, E-mail: daniele.pranzetti@gravity.fau.de [Institute for Quantum Gravity, University of Erlangen-Nürnberg (FAU), Staudtstrasse 7/B2, 91058 Erlangen (Germany)

2014-12-15

A quantum isolated horizon can be modelled by an SU(2) Chern–Simons theory on a punctured 2-sphere. We show how a local 2-dimensional conformal symmetry arises at each puncture inducing an infinite set of new observables localised at the horizon which satisfy a Kac–Moody algebra. By means of the isolated horizon boundary conditions, we represent the gravitational flux degrees of freedom in terms of the zero modes of the Kac–Moody algebra defined on the boundary of a punctured disk. In this way, our construction encodes a precise notion of CFT/gravity correspondence. The higher modes in the algebra represent new nongeometric charges which can be represented in terms of free matter field degrees of freedom. When computing the CFT partition function of the system, these new states induce an extra degeneracy factor, representing the density of horizon states at a given energy level, which reproduces the Bekenstein's holographic bound for an imaginary Immirzi parameter. This allows us to recover the Bekenstein–Hawking entropy formula without the large quantum gravity corrections associated with the number of punctures.

Biofilm-forming activity of bacteria isolated from toilet bowl biofilms and the bactericidal activity of disinfectants against the isolates.

Science.gov (United States)

Mori, Miho; Gomi, Mitsuhiro; Matsumune, Norihiko; Niizeki, Kazuma; Sakagami, Yoshikazu

2013-01-01

To evaluate the sanitary conditions of toilets, the bacterial counts of the toilet bowl biofilms in 5 Kansai area and 11 Kansai and Kanto area homes in Japan were measured in winter and summer seasons, respectively. Isolates (128 strains) were identified by analyzing 16S ribosomal RNA sequences. The number of colonies and bacterial species from biofilms sampled in winter tended to be higher and lower, respectively, than those in summer. Moreover, the composition of bacterial communities in summer and winter samples differed considerably. In summer samples, biofilms in Kansai and Kanto areas were dominated by Blastomonas sp. and Mycobacterium sp., respectively. Methylobacterium sp. was detected in all toilet bowl biofilms except for one sample. Methylobacterium sp. constituted the major presence in biofilms along with Brevundimonas sp., Sphingomonas sp., and/or Pseudomonas sp. The composition ratio of the sum of their genera was 88.0 from 42.9% of the total bacterial flora. The biofilm formation abilities of 128 isolates were investigated, and results suggested that Methylobacterium sp. and Sphingomonas sp. were involved in biofilm formation in toilet bowls. The biofilm formation of a mixed bacteria system that included bacteria with the highest biofilm-forming ability in a winter sample was greater than mixture without such bacteria. This result suggests that isolates possessing a high biofilm-forming activity are involved in the biofilm formation in the actual toilet bowl. A bactericidal test against 25 strains indicated that the bactericidal activities of didecyldimethylammonium chloride (DDAC) tended to be higher than those of polyhexamethylene biguanide (PHMB) and N-benzyl-N,N-dimethyldodecylammonium chloride (ADBAC). In particular, DDAC showed high bactericidal activity against approximately 90% of tested strains under the 5 h treatment.

Isolation of cells for selective treatment and analysis using a magnetic microfluidic chip

KAUST Repository

Yassine, Omar

2014-05-01

This study describes the development and testing of a magnetic microfluidic chip (MMC) for trapping and isolating cells tagged with superparamagnetic beads (SPBs) in a microfluidic environment for selective treatment and analysis. The trapping and isolation are done in two separate steps; first, the trapping of the tagged cells in a main channel is achieved by soft ferromagnetic disks and second, the transportation of the cells into side chambers for isolation is executed by tapered conductive paths made of Gold (Au). Numerical simulations were performed to analyze the magnetic flux and force distributions of the disks and conducting paths, for trapping and transporting SPBs. The MMC was fabricated using standard microfabrication processes. Experiments were performed with E. coli (K12 strand) tagged with 2.8 μm SPBs. The results showed that E. coli can be separated from a sample solution by trapping them at the disk sites, and then isolated into chambers by transporting them along the tapered conducting paths. Once the E. coli was trapped inside the side chambers, two selective treatments were performed. In one chamber, a solution with minimal nutrition content was added and, in another chamber, a solution with essential nutrition was added. The results showed that the growth of bacteria cultured in the second chamber containing nutrient was significantly higher, demonstrating that the E. coli was not affected by the magnetically driven transportation and the feasibility of performing different treatments on selectively isolated cells on a single microfluidic platform.

IDENTIFICATION AND BIOLOGICAL ACTIVITY OF POTENTIAL PROBIOTIC BACTERIA ISOLATED FROM POECILIA RETICULATA (GUPPY

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Aparna Balakrishna

2014-08-01

Full Text Available Antagonistic activities against candidate indicator strains, adhesion to mucus and biofilm formation of potential probiotic strains isolated from Poecilia reticulata were evaluated. Four isolated strains (MBTU_PB1, MBTU_PB2, MBTU_PB3 and MBTU_PB4 showed moderate to strong antagonistic activities against the tested five indicator strains (Aeromonas hydrophila1739, Vibrio cholera 3906, Flavobacterium 2495, Acinetobacter 1271 and Alcaligenes 1424 and these isolates were further identified using biochemical tests and 16S rDNA gene sequence analysis. Except the whole cell product, the other three cellular components, namely, heat-killed whole cell product, intracellular product and extracellular product of all the four selected isolates were equally effective, as revealed by the zone of inhibitions to the tested indicator strains. The in vitro adhesion property or the ability of colonization is often considered as a selection criteria for probiotics. All the selected four strains had higher adhesion abilities than the indicator strains. Further, these four strains had the ability to form biofilms on polystyrene surfaces. The in vitro characterization of these four strains suggests possibility of using the isolates, as individual strain or in combination, for probiotic therapy in aquaculture.

Isolation and characterization of Faecalibacterium prausnitzii from calves and piglets.

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Carla Foditsch

Full Text Available The goal of our study was to isolate and characterize Faecalibacterium prausnitzii from fecal samples of healthy calves and piglets, in order to develop a novel probiotic for livestock animals. We identified 203 isolates of Faecalibacterium sp., which were clustered in 40 genetically distinct groups. One representative isolate from each cluster was selected for further characterization. The concentrations of the short chain fatty acids (SCFA acetate, butyrate, propionate and isobutyrate in the culture media were measured by gas chromatography. We observed reduction in the concentration of acetate followed by concomitant increase in the concentration of butyrate, suggesting that the isolates were consuming acetate present in the media and producing butyrate. Butyrate production correlated positively with bacterial growth. Since butyrate has many benefits to the colonic epithelial cells, the selection of strains that produce higher amounts of butyrate is extremely important for the development of this potential probiotic. The effect of pH and concentration of bile salts on bacterial growth was also evaluated in order to mimic the conditions encountered by F. prausnitzii in vivo. The optimal pH for growth ranged between 5.5 and 6.7, while most isolates were inhibited by of the lowest concentration of bile salts tested (0.1%. Antimicrobial resistance profile showed that most isolates of Faecalibacterium sp. were resistant against ciprofloxacin and sulfamethoxazole-trimethoprim. More than 50% of the isolates were resistant to tetracycline, amikacin, cefepime and cefoxitin. A total of 19 different combinations of multidrug resistance were observed among the isolates. Our results provide new insights into the cultural and physiological characteristics of Faecalibacterium prausnitzii illustrating large variability in short chain fatty acid production, in vitro growth, sensitivity to bile salts, and antibiotic resistance and suggesting that future

Selection and characterisation of monepantel resistance in Teladorsagia circumcincta isolates

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D.J. Bartley

2015-08-01

To address these questions three MPTL-resistant Teladorsagia circumcincta isolates (MTci2-11, MTci5-13 and MTci7-12 have been artificially selected in vivo from phenotypically characterised parent isolates (MTci2, MTci5, MTci7 respectively. The selection process involved collecting and culturing eggs from surviving worms from sheep administered sub-optimal dosages of MPTL (Zolvix® to provide infective larvae to infect further sheep until resistant isolates were generated (between 9 and 13 rounds of selection. A controlled efficacy test was conducted using the original parental isolates and the newly generated MPTL resistant isolates (n = 5 per group. Selected isolates were assessed both under anthelmintic stress (Zolvix®, 2.5 mg/kg bodyweight; MTci-MPTL and at rest (untreated, MTci-CON. A number of life-history traits were assessed, namely, worm establishment rates, time to patency, faecal egg output, body length of adults and eggs in utero. The estimated resistance status of the selected isolates was confirmed with 48%, 28% and 9% reductions in worm burden at 7-days post Zolvix® administration for MTci2-11-MPTL, MTci5-13-MPTL and MTci7-12-MPTL, respectively, compared with untreated controls. One of the selected isolates MTci7-12-CON showed significantly greater total worm burden (p = 0.025, greater establishment rate (p = 0.033, decreased time to patency (p = 0.048, higher cumulative egg outputs (p = 0.002 compared with its parental derivative MTci7. The trial results suggest that anthelmintic selection in T. circumcincta, albeit under experimental conditions, can select for more prolific/fecund and quicker maturing populations. These data provide an insight into how parasites evolve in response to anthelmintic pressure.

Entomopathogens Isolated from Invasive Ants and Tests of Their Pathogenicity

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Maria Fernanda Miori de Zarzuela

2012-01-01

Full Text Available Some ant species cause severe ecological and health impact in urban areas. Many attempts have been tested to control such species, although they do not always succeed. Biological control is an alternative to chemical control and has gained great prominence in research, and fungi and nematodes are among the successful organisms controlling insects. This study aimed to clarify some questions regarding the biological control of ants. Invasive ant species in Brazil had their nests evaluated for the presence of entomopathogens. Isolated entomopathogens were later applied in colonies of Monomorium floricola under laboratory conditions to evaluate their effectiveness and the behavior of the ant colonies after treatment. The entomopathogenic nematodes Heterorhabditis sp. and Steinernema sp. and the fungi Beauveria bassiana, Metarhizium anisopliae, and Paecilomyces sp. were isolated from the invasive ant nests. M. floricola colonies treated with Steinernema sp. and Heterorhabditis sp. showed a higher mortality of workers than control. The fungus Beauveria bassiana caused higher mortality of M. floricola workers. However, no colony reduction or elimination was observed in any treatment. The defensive behaviors of ants, such as grooming behavior and colony budding, must be considered when using fungi and nematodes for biological control of ants.

[A study on genotype of 271 mycobacterium tuberculosis isolates in 6 prefectures in Yunnan Province].

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Chen, L Y; Yang, X; Ru, H H; Yang, H J; Yan, S Q; Ma, L; Chen, J O; Yang, R; Xu, L

2018-01-06

Objective: To understand the characteristics of genotypes of Mycobacterium tuberculosis isolates in Yunnan province, and provide the molecular epidemiological evidence for prevention and control of tuberculosis in Yunnan Province. Methods: Mycobacterium Tuberculosis isolates were collected from 6 prefectures of Yunnan province in 2014 and their Genetypes of Mycobacterium tuberculosis isolates were obtained using spoligotyping and multiple locus variable numbers of tandem repeats analysis (MLVA). The results of spoligotyping were entered into the SITVITWEB database to obtain the Spoligotyping International Type (SIT) patterns and the sublineages of MTB isolates. The genoyping patterns were clustered with BioNumerics (version 5.0). Results: A total of 271 MTB isolates represented patients were collected from six prefectures in Yunnan province. Out of these patients, 196 (72.3%) were male. The mean age of the patients was (41.9±15.1) years. The most MTB isolates were from Puer, totally 94 iusolates(34.69%). Spoligotyping analysis revealed that 151 (55.72%) MTB isolates belonged to the Beijing genotype, while the other 120 (44.28%) were from non-Beijing genotype; 40 genotypes were consisted of 24 unique genotypes and 16 clusters. The 271 isolates were differentiated into 30 clusters (2 to 17 isolates per cluster) and 177 unique genotypes, showing a clustering rate of 23.62%. Beijing genotype strains showed higher clustering rate than non-Beijing genotype strains (29.14% vs 16.67%). The HGI of 12-locus VNTR in total MTB strains, Beijing genotype strains and non-Beijing genotype was 0.993, 0.982 and 0.995 respectively. Conclusion: The Beijing genotype was the predominant genotype in Yunnan Province, the characteristics of Mycobacterium tuberculosis showed high genetic diversity. The genotyping data reflect the potential recent ongoing transmission in some area, which highlights the urgent need for early diagnosis and treatment of the infectious TB cases, to cut off the

Candida tropicalis from veterinary and human sources shows similar in vitro hemolytic activity, antifungal biofilm susceptibility and pathogenesis against Caenorhabditis elegans.

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Brilhante, Raimunda Sâmia Nogueira; Oliveira, Jonathas Sales de; Evangelista, Antônio José de Jesus; Serpa, Rosana; Silva, Aline Lobão da; Aguiar, Felipe Rodrigues Magalhães de; Pereira, Vandbergue Santos; Castelo-Branco, Débora de Souza Collares Maia; Pereira-Neto, Waldemiro Aquino; Cordeiro, Rossana de Aguiar; Sidrim, José Júlio Costa; Rocha, Marcos Fábio Gadelha

2016-08-30

The aim of this study was to evaluate the in vitro hemolytic activity and biofilm antifungal susceptibility of veterinary and human Candida tropicalis strains, as well as their pathogenesis against Caenorhabditis elegans. Twenty veterinary isolates and 20 human clinical isolates of C. tropicalis were used. The strains were evaluated for their hemolytic activity and biofilm production. Biofilm susceptibility to itraconazole, fluconazole, voriconazole, amphotericin B and caspofungin was assessed using broth microdilution assay. The in vivo evaluation of strain pathogenicity was investigated using the nematode C. elegans. Hemolytic factor was observed in 95% of the strains and 97.5% of the isolates showed ability to form biofilm. Caspofungin and amphotericin B showed better results than azole antifungals against mature biofilms. Paradoxical effect on mature biofilm metabolic activity was observed at elevated concentrations of caspofungin (8-64μg/mL). Azole antifungals were not able to inhibit mature C. tropicalis biofilms, even at the higher tested concentrations. High mortality rates of C. elegans were observed when the worms were exposed to with C. tropicalis strains, reaching up to 96%, 96h after exposure of the worms to C. tropicalis strains. These results reinforce the high pathogenicity of C. tropicalis from veterinary and human sources and show the effectiveness of caspofungin and amphotericin B against mature biofilms of this species. Copyright © 2016 Elsevier B.V. All rights reserved.

Preparation and characterization of baru (Dipteryx alata Vog) nut protein isolate and comparison of its physico-chemical properties with commercial animal and plant protein isolates.

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Nunes, Ângela A; Favaro, Simone P; Miranda, Cesar H B; Neves, Valdir A

2017-01-01

The Brazilian leguminous tree locally known in the Cerrado Biome as baru (Dipteryx alata Vog), provides a healthy edible oil source. The proteinaceous cake remaining after oil extraction could be transformed into new products to foodstuff development, such as protein concentrates and isolates, adding value to the production chain. In this study, it is described the preparation and characterization of baru nut protein isolate (BPI) from deffated baru flour, and measurements of its functional, nutritional, and thermal properties, in comparison to the more common vegetable (soybeans) and animal (casein and albumin) protein sources of the food industry. BPI presented higher protein content than soybean, casein and albumin commercial protein isolates, despite losses of albumins and low molecular weight globulins during the isolation procedure. Thermodynamics studies suggested that BPI has a well-conserved protein arrangement and lower thermostability than the other protein sources. BPI showed high in vitro digestibility and suitable and desirable functional properties such as water and oil absorption capacity, emulsifying activity, and foam formation and stability at mild and neutral pH. BPI could be used either as a substitute ingredient in oily food formulations or in the development of new products of its own. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Zeaxanthin Radical Cation Formation in Minor Light-Harvesting Complexes of Higher Plant Antenna

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Avenson, Thomas H.; Ahn, Tae Kyu; Zigmantas, Donatas; Niyogi, Krishna K.; Li, Zhirong; Ballottari, Matteo; Bassi, Roberto; Fleming, Graham R.

2008-01-31

Previous work on intact thylakoid membranes showed that transient formation of a zeaxanthin radical cation was correlated with regulation of photosynthetic light-harvesting via energy-dependent quenching. A molecular mechanism for such quenching was proposed to involve charge transfer within a chlorophyll-zeaxanthin heterodimer. Using near infrared (880-1100 nm) transient absorption spectroscopy, we demonstrate that carotenoid (mainly zeaxanthin) radical cation generation occurs solely in isolated minor light-harvesting complexes that bind zeaxanthin, consistent with the engagement of charge transfer quenching therein. We estimated that less than 0.5percent of the isolated minor complexes undergo charge transfer quenching in vitro, whereas the fraction of minor complexes estimated to be engaged in charge transfer quenching in isolated thylakoids was more than 80 times higher. We conclude that minor complexes which bind zeaxanthin are sites of charge transfer quenching in vivo and that they can assume Non-quenching and Quenching conformations, the equilibrium LHC(N)<--> LHC(Q) of which is modulated by the transthylakoid pH gradient, the PsbS protein, and protein-protein interactions.

Genetic diversity among brazilian isolates of beauveria bassiana: comparisons with non-brazilian isolates and other beauveria species

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Fernandes, E.K.K.; Moraes, A.M.L.; Pacheco, R.S.; Rangel, D.E.N.; Miller, M.P.; Bittencourt, V.R.E.P.; Roberts, D.W.

2009-01-01

Aims: The genetic diversity of Beauveria bassiana was investigated by comparing isolates of this species to each other (49 from different geographical regions of Brazil and 4 from USA) and to other Beauveria spp. Methods and Results: The isolates were examined by multilocus enzyme electrophoresis (MLEE), amplified fragment length polymorphism (AFLP), and rDNA sequencing. MLEE and AFLP revealed considerable genetic variability among B. bassiana isolates. Several isolates from South and Southeast Brazil had high similarity coefficients, providing evidence of at least one population with clonal structure. There were clear genomic differences between most Brazilian and USA B. bassiana isolates. A Mantel test using data generated by AFLP provided evidence that greater geographical distances were associated with higher genetic distances. AFLP and rDNA sequencing demonstrated notable genotypic variation between B. bassiana and other Beauveria spp. Conclusion: Geographical distance between populations apparently is an important factor influencing genotypic variability among B. bassiana populations in Brazil. Significance and Impact of the Study: This study characterized many B. bassiana isolates. The results indicate that certain Brazilian isolates are considerably different from others and possibly should be regarded as separate species from B. bassiana sensu latu. The information on genetic variation among the Brazilian isolates, therefore, will be important to comprehending the population structure of B. bassiana in Brazil. ?? 2009 The Society for Applied Microbiology.

The expression of extracellular fungal cell wall hydrolytic enzymes in different Trichoderma harzianum isolates correlates with their ability to control Pyrenochaeta lycopersici

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LUZ MARÍA PÉREZ

2002-01-01

Full Text Available Four isolates of Trichoderma harzianum (ThN3, Th11, Th12 and Th16 were selected for their ability to control the in vitro development of the tomato root pathogen Pyrenochaeta lycopersici. Analysis of the mechanisms involved in biocontrol showed that the formation of non-volatile metabolites appears to be one of those involved in biocontrol of P. lycopersici by all T. harzianum isolates tested. Nevertheless, the higher secretion of chitinases, both in number of isoenzymes and activity by the Th11 strain, correlated well with its higher ability to control this agent in laboratory and greenhouse experiments as compared to the other T. harzianum isolates tested. The secretion of ß -1,3-endoglucanases and/or proteases appeared to have less significance than endochitinases in the biological control of P. lycopersici

Multiple, novel biologically active endophytic actinomycetes isolated from upper Amazonian rainforests.

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Bascom-Slack, Carol A; Ma, Cong; Moore, Emily; Babbs, Beatrice; Fenn, Kathleen; Greene, Joshua S; Hann, Bradley D; Keehner, Jocelyn; Kelley-Swift, Elizabeth G; Kembaiyan, Vivek; Lee, Sun Jin; Li, Puyao; Light, David Y; Lin, Emily H; Schorn, Michelle A; Vekhter, Daniel; Boulanger, Lori-Ann; Hess, W M; Vargas, Percy Núñez; Strobel, Gary A; Strobel, Scott A

2009-08-01

Microbial biodiversity provides an increasingly important source of medically and industrially useful compounds. We have isolated 14 actinomycete species from a collection of approximately 300 plant stem samples from the upper Amazonian rainforest in Peru. All of the cultured isolates produce substances with inhibitory activity directed at a range of potential fungal and bacterial pathogens. For some organisms, this activity is very broad in spectrum while other organisms show specific activity against a limited number of organisms. Two of these organisms preferentially inhibit bacterial test organisms over eukaryotic organisms. rDNA sequence analysis indicates that these organisms are not equivalent to any other cultured deposits in GenBank. Our results provide evidence of the untapped biodiversity in the form of biologically active microbes present within the tissues of higher plants.

Rearing of germfree chicks in a vinyl isolator

International Nuclear Information System (INIS)

Ishibashi, Teru; Kametaka, Masao; Ozaki, Akira; Yamamoto, Tetsuzo; Kaneuchi, Choji.

1977-01-01

A method of rearing germfree chicks in a vinyl isolator was developed, Hatchability of eggs was higher than 95% when eggs were sterilized in a 1.5% mercuric chloride solution on the 2nd day before hatching. Sterility was 93% when 5 to 10 chicks were reared in a vinyl isolator for 2 weeks. Depression of body weight gain was observed in chicks fed diet irradiated at higher than 4 Mrad. However, no effects of irradiation on chick growth were observed when fat and the other components were sterilized separately and mixed before feeding. The growth rates of germfree chicks were higher than those of the conventional chicks which were supplied a diluted solution of fresh cecum feces of young hens with a normal intestinal flora pattern at the first feeding. (auth.)

Genetic diversity and antimicrobial resistance of Campylobacter and Salmonella strains isolated from decoys and raptors.

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Jurado-Tarifa, E; Torralbo, A; Borge, C; Cerdà-Cuéllar, M; Ayats, T; Carbonero, A; García-Bocanegra, I

2016-10-01

Infections caused by thermotolerant Campylobacter spp. and Salmonella spp. are the leading causes of human gastroenteritis worldwide. Wild birds can act as reservoirs of both pathogens. A survey was carried out to determine the prevalence, genetic diversity and antimicrobial resistance of thermotolerant Campylobacter and Salmonella in waterfowl used as decoys and wild raptors in Andalusia (Southern Spain). The overall prevalence detected for Campylobacter was 5.9% (18/306; CI95%: 3.25-8.52) in decoys and 2.3% (9/387; CI95%: 0.82-3.83) in wild raptors. Isolates were identified as C. jejuni, C. coli and C. lari in both bird groups. Salmonella was isolated in 3.3% (10/306; CI95%: 2.3-4.3) and 4.6% (18/394; CI95%: 3.5-5.6) of the decoys and raptors, respectively. Salmonella Enteritidis and Typhimurium were the most frequently identified serovars, although Salmonella serovars Anatum, Bredeney, London and Mikawasima were also isolated. Pulsed-field gel electrophoresis analysis of isolates showed higher genetic diversity within Campylobacter species compared to Salmonella serovars. Campylobacter isolates showed resistance to gentamicin, ciprofloxacin and tetracycline, while resistance to erythromycin and tetracycline was found in Salmonella isolates. The results indicate that both decoys and raptors can act as natural carriers of Campylobacter and Salmonella in Spain, which may have important implications for public and animal health. Copyright © 2016 Elsevier Ltd. All rights reserved.

Toxigenic profile of methicillin-sensitive and resistant Staphylococcus aureus isolated from special groups.

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de Souza, Camila Sena Martins; Fortaleza, Carlos Magno Castelo Branco; Witzel, Claudia Lima; Silveira, Mônica; Bonesso, Mariana Fávero; Marques, Silvio Alencar; Cunha, Maria de Lourdes Ribeiro de Souza da

2016-02-16

Staphylococcus aureus is characterized by its pathogenicity and high prevalence, causing disease in both healthy and immunocompromised individuals due to its easy dissemination. This fact is aggravated by the widespread dissemination of S. aureus carrying toxigenic genes. The objective of this study was to determine the toxigenic profile of methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) in patients with purulent skin and/or soft tissue infections seen at the Dermatology Department of the University Hospital of the Botucatu Medical School, asymptomatic adults older than 60 years living in nursing homes, and prison inmates of the Avaré Detention Center. PCR was used for the detection of the mecA gene, enterotoxin genes (sea, seb, and sec), exfoliative toxins A and B (eta and etb), toxic shock syndrome toxin 1 (tst), panton-valentine leukocidin (lukS-PV and lukF-PV), and alpha- and delta-hemolysins or cytotoxins (hla and hld). The results showed a significant prevalence of toxigenic genes among S. aureus isolates from asymptomatic individuals, with the observation of a higher prevalence of cytotoxin genes. However, the panton-valentine leukocidin gene was only detected in MSSA isolated from patients with skin infections and the tst gene was exclusively found in MSSA isolated from prison inmates. The present study demonstrated a significant prevalence of toxigenic genes in MSSA and MRSA strains isolated from asymptomatic S. aureus carriers. There was a higher prevalence of cytotoxin genes.

Prevalence and Biotyping of Pasteurella Haemolytica Isolates from ...

African Journals Online (AJOL)

P. haemolytica isolated from Sahel sheep and goat in Maiduguri was characterized phenotypically. A total of 92 P. haemolytica isolates were obtained from the nasopharyngeal swabs while a total of 15 isolates came from pneumonic lung samples. The results showed that 37(20.22%) P. haemolytica isolates were obtained ...

Two bee-pollinated plant species show higher seed production when grown in gardens compared to arable farmland.

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John Cussans

2010-07-01

Full Text Available Insect pollinator abundance, in particular that of bees, has been shown to be high where there is a super-abundance of floral resources; for example in association with mass-flowering crops and also in gardens where flowering plants are often densely planted. Since land management affects pollinator numbers, it is also likely to affect the resultant pollination of plants growing in these habitats. We hypothesised that the seed or fruit set of two plant species, typically pollinated by bumblebees and/or honeybees might respond in one of two ways: 1 pollination success could be reduced when growing in a floriferous environment, via competition for pollinators, or 2 pollination success could be enhanced because of increased pollinator abundance in the vicinity.We compared the pollination success of experimental plants of Glechoma hederacea L. and Lotus corniculatus L. growing in gardens and arable farmland. On the farms, the plants were placed either next to a mass-flowering crop (oilseed rape, Brassica napus L. or field beans, Vicia faba L. or next to a cereal crop (wheat, Triticum spp.. Seed set of G. hederacea and fruit set of L. corniculatus were significantly higher in gardens compared to arable farmland. There was no significant difference in pollination success of G. hederacea when grown next to different crops, but for L. corniculatus, fruit set was higher in the plants growing next to oilseed rape when the crop was in flower.The results show that pollination services can limit fruit set of wild plants in arable farmland, but there is some evidence that the presence of a flowering crop can facilitate their pollination (depending on species and season. We have also demonstrated that gardens are not only beneficial to pollinators, but also to the process of pollination.

Isolation and partial characterization of starch from banana cultivars grown in Colombia.

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Chávez-Salazar, A; Bello-Pérez, L A; Agama-Acevedo, E; Castellanos-Galeano, F J; Álvarez-Barreto, C I; Pacheco-Vargas, G

2017-05-01

Banana starch is resistant to hydrolysis by digestive enzymes due to its structure and dietary fibre content. Starch was isolated from the following three cultivars of Colombian Musaceae: Gros Michel (dessert), Dominico Harton and FHIA 20 (cooking); also, the amylose and amylopectin contents, morphology of the granules, thermal properties, pasting, molecular characteristics and digestibility were determined. The total starch content, amylose content and digestibility (gelatinized starch) were higher in cooking varieties; the purity and gelatinization temperature were similar for the three varieties, but the enthalpy was higher in the dessert variety. The three varieties showed higher viscosities in the pasting profile compared to commercial maize starch in both acid and neutral conditions. Starch granules presented with heterogeneous sizes and shapes (elongated and ovals) that had birefringence. The Dominico Hartón variety showed the lowest rapidly digestible starch (RDS) value in the gelatinized sample that is in agreement with the greater proportion of long chains. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of isolation techniques on the characteristics of pigeon pea (Cajanus cajan) protein isolates.

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Adenekan, Monilola K; Fadimu, Gbemisola J; Odunmbaku, Lukumon A; Oke, Emmanuel K

2018-01-01

In this study, the effect of different isolation techniques on the isolated proteins from pigeon pea was investigated. Water, methanol, ammonium sulfate, and acetone were used for the precipitation of proteins from pigeon pea. Proximate composition, and antinutritional and functional properties of the pigeon pea flour and the isolated proteins were measured. Data generated were statistically analyzed. The proximate composition of the water-extracted protein isolate was moisture 8.30%, protein 91.83%, fat 0.25%, ash 0.05%, and crude fiber 0.05%. The methanol-extracted protein isolate composition was moisture 7.87%, protein 91.83%, fat 0.17%, and ash 0.13%, while crude fiber and carbohydrates were not detected. The composition of the ammonium sulfate-extracted protein isolate was moisture 7.73%, protein 91.73%, fat 0.36, ash 0.13%, and crude fiber 0.67%. The acetone-extracted protein isolate composition was moisture 8.03%, protein 91.50%, ash 0.67%, and fat 0.30%, but crude fiber and carbohydrates were not detected. The isolate precipitated with ammonium sulfate displayed the highest foaming capacity (37.63%) and foaming stability (55.75%). Isolates precipitated with methanol and acetone had the highest water absorption capacity (160%). Pigeon pea protein isolates extracted with methanol and ammonium sulfate had the highest oil absorption capacity of 145%. Protein isolates recovered through acetone and methanol had the highest emulsifying capacity of 2.23% and emulsifying stability of 91.47%, respectively. The proximate composition of the recovered protein isolates were of high purity. This shows the efficiency of the extraction techniques. The isolates had desirable solubility index. All the isolation techniques brought significant impact on the characteristics of the isolated pigeon pea protein.

Single spore isolation and morphological characterization of local Malaysian isolates of rice blast fungus Magnoporthe grisea

Science.gov (United States)

Mishra, Ankitta; Ratnam, Wickneswari; Bhuiyan, Md Atiqur Rahman; Ponaya, Ariane; Jena, Khisord K.

2015-09-01

Rice blast is a destructive disease, caused by the fungal pathogen Magnaporthe grisea. It causes considerable damage to rice and leads to crop loss in rice growing regions worldwide. Although fungicides can be used to control rice blast, they generate additional cost in rice production and contamination of environment and food. Therefore, the use of resistant varieties is thought to be one of the most economically and environmentally efficient ways of crop protection from the disease. Six new local Malaysian isolates of M. grisea were isolated using single spore isolation method. Five isolates were from infected leaf samples collected from Kompleks Latihan MADA, Kedah and one was from Kelantan. These isolates were identified using morphological characteristics and microscopic studies and later confirmed by ITSequences. These isolates were induced to sporulate and used for greenhouse screening on two differential rice varieties: Mahsuri (susceptible) and Pongsu Seribu 2 (resistant). Among the 6 isolates, isolate number 3 was found to be the most virulent showing high sporulation while isolate number 4 was very slow growing, and the least virulent.

Molecular differentiation of sheep and cattle isolates of Fasciola hepatica using RAPD-PCR

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Khakpour, M.

2012-11-01

Full Text Available Understanding genetic structure and status of genetic variation of Fasciola hepatica isolates from different hosts, has important implications on epidemiology and effective control of fasciolosis. Random amplified polymorphic DNA (RAPD-PCR was used to study the genetic variation of F. hepatica in sheep and cattle. DNA was extracted from adult helminthes removed from livers of each infected animal in slaughterhouse at East-Azerbaijan province, North-West of Iran. DNA template amplified by the polymerase chain reaction, using three oligonucleotide decamers with arbitrary DNA sequences as primers. RAPD patterns showed the specific but different pattern DNA patterns for each primer. The intraspecific similarity coefficient within two isolates of F. hepatica was ranged between 69 to 100%. Present findings showed that the interspecific genetic distance was higher than intraspecific genetic distances (19-47% compares to 0-19%. Pair wise similarity matrices generated from each isolates-primer combination were totaled and the similarity coefficient between strains were calculated both manually (Nei and Li method and software analysis (Free-Tree-Freeware program. The inferred phylogenetic tree on the fingerprinting of these isolates clearly demonstrated the existence of population genetic diversity sub structuring within F. hepatica of sheep and cattle of Iran, raising interesting questions on the host specificity, epidemiology (e.g., zoonotic transmission and ecology of this fluke. RAPD-PCR is useful for both individual identification and epidemiological investigations in endemic regions.

Compost as a source of microbial isolates for the bioremediation of heavy metals: In vitro selection

International Nuclear Information System (INIS)

Vargas-García, María del Carmen; López, María José; Suárez-Estrella, Francisca; Moreno, Joaquín

2012-01-01

Heavy metal pollution has become a major environmental concern nowadays and the bioremediation of polluted habitats is an increasingly popular strategy due to both its efficiency and safety. A screening and selection protocol based on different composting processes was designed in order to isolate heavy metal-resistant microorganisms. A collection of 51 microorganisms was obtained and most of them showed the capability to tolerate heavy metals in multi-polluted aqueous systems (Cd(II), Cr(VI), Ni, Pb, Zn(II)), as well as to remove them. The highest detoxification ratios were observed for Pb. Some of the isolates detoxifying more than a 90% of this metal, while the other metals were removed in a range between 20% and 60%. The best isolates (Graphium putredinis, Fusarium solani, Fusarium sp. and Penicillium chrysogenum) were further assayed in order to determine the predominant removal mechanism and the potential use of their dead biomass as a biosorbent. Intracellular accumulation was the prevalent mechanism for most isolates and metals, with the exception of Ni. In this case, the proportion removed by extracellular adsorption was similar or even higher than that removed by intracellular accumulation. Thus, the efficiency of living cells was higher than that of dead biomass except in the case of Ni. - Highlights: ► Composting is a good reservoir for the isolation of HM-resistant microorganisms. ► Pb was the most removed heavy metal in multi-polluted aqueous systems. ► Intracellular accumulation was the predominant mechanism for heavy metal removal. ► Graphium putredinis, which detoxifies organic pollutants, was the most efficient isolate.

Characterisation of Commensal Escherichia coli Isolated from Apparently Healthy Cattle and Their Attendants in Tanzania.

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Balichene P Madoshi

Full Text Available While pathogenic types of Escherichia coli are well characterized, relatively little is known about the commensal E. coli flora. In the current study, antimicrobial resistance in commensal E. coli and distribution of ERIC-PCR genotypes among isolates of such bacteria from cattle and cattle attendants on cattle farms in Tanzania were investigated. Seventeen E. coli genomes representing different ERIC-PCR types of commensal E. coli were sequenced in order to determine their possible importance as a reservoir for both antimicrobial resistance genes and virulence factors. Both human and cattle isolates were highly resistant to tetracycline (40.8% and 33.1%, sulphamethazole-trimethoprim (49.0% and 8.8% and ampicillin (44.9% and 21.3%. However, higher proportion of resistant E. coli and higher frequency of resistance to more than two antimicrobials was found in isolates from cattle attendants than isolates from cattle. Sixteen out of 66 ERIC-PCR genotypes were shared between the two hosts, and among these ones, seven types contained isolates from cattle and cattle attendants from the same farm, suggesting transfer of strains between hosts. Genome-wide analysis showed that the majority of the sequenced cattle isolates were assigned to phylogroups B1, while human isolates represented phylogroups A, C, D and E. In general, in silico resistome and virulence factor identification did not reveal differences between hosts or phylogroups, except for lpfA and iss found to be cattle and B1 phylogroup specific. The most frequent plasmids replicon genes found in strains from both hosts were of IncF type, which are commonly associated with carriage of antimicrobial and virulence genes. Commensal E. coli from cattle and attendants were found to share same genotypes and to carry antimicrobial resistance and virulence genes associated with both intra and extraintestinal E. coli pathotypes.

Polymer Film-Based Screening and Isolation of Polylactic Acid (PLA)-Degrading Microorganisms.

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Kim, Mi Yeon; Kim, Changman; Moon, Jungheun; Heo, Jinhee; Jung, Sokhee P; Kim, Jung Rae

2017-02-28

Polylactic acid (PLA) has been highlighted as an alternative renewable polymer for the replacement of petroleum-based plastic materials, and is considered to be biodegradable. On the other hand, the biodegradation of PLA by terminal degraders, such as microorganisms, requires a lengthy period in the natural environment, and its mechanism is not completely understood. PLA biodegradation studies have been conducted using mainly undefined mixed cultures, but only a few bacterial strains have been isolated and examined. For further characterization of PLA biodegradation, in this study, the PLA-degrading bacteria from digester sludge were isolated and identified using a polymer film-based screening method. The enrichment of sludge on PLA granules was conducted with the serial transference of a subculture into fresh media for 40 days, and the attached biofilm was inoculated on a PLA film on an agar plate. 3D optical microscopy showed that the isolates physically degraded the PLA film due to bacterial degradation. 16S rRNA gene sequencing identified the microbial colonies to be Pseudomonas sp. MYK1 and Bacillus sp. MYK2. The two isolates exhibited significantly higher specific gas production rates from PLA biodegradation compared with that of the initial sludge inoculum.

Isolation and characterization of cellulolytic Bacillus licheniformis ...

African Journals Online (AJOL)

Eight cellulose degrading bacteria were isolated from compost and were identified as Bacillus licheniformis by 16S rRNA sequencing. Among the eight isolates, Bacillus licheniformis B4, B7 and B8 showed the highest cellulase activity. B. licheniformis B4 and B8 showed the maximum cellulase activity during the stationary ...

Molecular Detection of Inducible Clindamycin Resistance among Staphylococcal Strains Isolated from Hospital Patients

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Shadiyeh Abdollahi

2013-04-01

Full Text Available Background & Objectives: Macrolide, lincosamide and streptogramin B (MLSB antimicrobial agents are used in the treatment of staphylococcal infections. They prevent the microbial protein synthesis system through binding to 23 S rRNA. The aim of this study was to apply molecular methods to detect inducible clindamycin resistance genes among staphylococcal strains isolated from clinical specimens.   Methods : Two hundred staphylococcus strains were isolated from nose and throat swabs of patients in Toohid and Besat hospitals in Sanandaj . Antimicrobial susceptibilities of isolates were determined using disc diffusion method, agar screen test and D-Test. A multiplex PCR was performed using primers specific for erm (A, B, C, TR genes.   Results: Out of 200 isolates, 18.5 % were MRSA and 32% were MRCNS (methicillin resistant coagulase negative staphylococci. Of 80 erythromycin resistant isolates, 48 were coagulase negative and 32 were S. aureus. Among the 48 coagulase negative staphylococci (CONS isolates, 11.63% expressed the MLSB-inducible phenotypes. Using PCR, the frequency of different genes in the collection of isolates were as follows: ermA 5.41 % , erm B 5.41 % , and erm C 3.13%. The ermTR gene was negative in all isolates. Among the 32 S. aureus isolates, 9.38% expressed the MLSB-nducible phenotype. Using PCR, these isolates harbored erm A (2.22%, ermB (2.22%, ermC (2.22% and ermTR (2.22% .   Conclusion: This is the first study to show the rate of inducible clindamycin clinical isolates of staphylococci harboring erm genes in Sananadaj. It also demonstrated the frequency of erm genes was higher among CONS isolates than S. aureus. This data suggested the transfer of resistance gene from nonpathogenic to pathogenic strains is likely to happen. Therefore, screening and control of these resistance genes is recommended at clinical laboratories.

Genetic characterization of Toxoplasma gondii isolates from Portugal, Austria, and Israel reveals higher genetic variability within the type II lineage

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This study compared genetic diversity of Toxoplasma gondii isolates from Portugal, Austria and Israel. For this, we genotyped 90 T. gondii isolates (16 from Portugal, 67 from Austria and 7 from Israel) using 10 nested PCR-restriction length polymorphism (RFLP) genetic markers and 15 microsatellite (...

Technical note: Antimicrobial susceptibility of Portuguese isolates of Staphylococcus aureus and Staphylococcus epidermidis in subclinical bovine mastitis.

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Nunes, S F; Bexiga, R; Cavaco, L M; Vilela, C L

2007-07-01

To evaluate the antimicrobial resistance traits of staphylococci responsible for subclinical bovine mastitis in Portugal, the minimum inhibitory concentrations (MIC) of 7 antimicrobial agents, frequently administered for mastitis treatment, were determined for 30 Staphylococcus aureus and 31 Staphylococcus epidermidis field isolates. Beta-lactamase production was detected through the use of nitrocefin-impregnated discs. The MIC that inhibited 90% of the isolates tested (MIC90) of penicillin, oxacillin, cefazolin, gentamicin, sulfamethoxazole/trimethoprim, oxytetracycline, and enrofloxacin were, respectively, 4, 0.5, 1, 1, 0.25, 0.25, and 0.06 microg/mL for Staph. aureus and > or = 64, 8, 1, 32, > or = 64, > or = 64, and 0.06 microg/mL for Staph. epidermidis. All Staph. aureus isolates showed susceptibility to oxacillin, cefazolin, gentamicin, sulphamethoxazole/trimethoprim, and enrofloxacin. Beta-lactamase production was detected in 20 of these isolates (66.7%), all of which were resistant to penicillin. Of the 31 Staph. epidermidis tested, 24 (77.4%) were beta-lactamase positive. All isolates were susceptible to both cefazolin and enrofloxacin. Nine Staph. epidermidis isolates were resistant to oxacillin, with MIC values ranging from 4 to 8 microg/mL. The MIC values of 5 antimicrobial agents tested were higher than those reported in other countries. Enrofloxacin was the only exception, showing lower MIC values compared with other reports. Overall, the antimicrobial agents tested in our study, with the exception of penicillin, were active against the 61 isolates studied.

Phylogenetic groups among Klebsiella pneumoniae isolates from Brazil: relationship with antimicrobial resistance and origin.

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de Melo, Maíra Espíndola Silva; Cabral, Adriane Borges; Maciel, Maria Amélia Vieira; da Silveira, Vera Magalhães; de Souza Lopes, Ana Catarina

2011-05-01

The objectives of this study were to determine the distribution of phylogenetic groups among Klebsiella pneumoniae isolates from Recife, Brazil and to assess the relationship between the groups and the isolation sites and resistance profile. Ninety four isolates of K. pneumoniae from hospital or community infections and from normal microbiota were analyzed by gyrA PCR-RFLP, antibiotic susceptibility, and adonitol fermentation. The results revealed the distinction of three phylogenetic groups, as it has also been reported in Europe, showing that these clusters are highly conserved within K. pneumoniae. Group KpI was dominantly represented by hospital and community isolates while groups KpII and KpIII displayed mainly normal microbiota isolates. The resistance to third generation cephalosporins, aztreonam, imipenem, amoxicillin/clavulanic acid, and streptomycin was only observed in KpI. The percentage of resistance was higher in KpI, followed by KpII and KpIII. The differences in the distribution of K. pneumoniae phylogenetic groups observed in this study suggest distinctive clinical and epidemiological characteristics among the three groups, which is important to understand the epidemiology of infections caused by this organism. This is the first study in Brazil on K. pneumoniae isolates from normal microbiota and community infections regarding the distribution of phylogenetic groups based on the gyrA gene.

Isolated Diastolic Hypertension Associated Risk Factors among Chinese in Anhui Province, China

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Yanchun Wang

2015-04-01

Full Text Available Objective: To explore potential risk factors of isolated diastolic hypertension (IDH among young and middle-aged Chinese. Methods: A community-based cross-sectional study was conducted among 338 subjects, aged 25 years and above, using random sampling technique. There were 68 cases of IDH, 46 cases of isolated systolic hypertension (ISH, 89 cases of systolic and diastolic hypertension (SDH, and 135 of subjects with normal blood pressure. Cases and controls were matched on sex by frequency matching. Demographic characteristics, blood pressure and other relevant information were collected. Results: Compared with controls, patients with IDH and ISH had significant higher level of triglyceride, high density lipoprotein, blood glucose and body mass index (BMI (p < 0.05; while patients with SDH had significantly higher level of total cholesterol, triglyceride, glucose and BMI (p < 0.05. Linear mixed effects model showed that drinking tea, family history of hypertension (FHH, higher blood glucose, triglyceride and low density lipoprotein were related with elevated diastolic blood pressure (DBP (p < 0.01; HFH, blood glucose, creatinine and BMI have positive effect on systolic blood pressure (SBP (p < 0.05. Conclusions: Drinking tea, FHH, high levels of triglyceride, high density lipoprotein, blood glucose and BMI are associated with IDH among young and middle-aged Chinese.

Effects of Hydrogen Peroxide on Different Toxigenic and Atoxigenic Isolates of Aspergillus flavus

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Jake C. Fountain

2015-08-01

Full Text Available Drought stress in the field has been shown to exacerbate aflatoxin contamination of maize and peanut. Drought and heat stress also produce reactive oxygen species (ROS in plant tissues. Given the potential correlation between ROS and exacerbated aflatoxin production under drought and heat stress, the objectives of this study were to examine the effects of hydrogen peroxide (H2O2-induced oxidative stress on the growth of different toxigenic (+ and atoxigenic (− isolates of Aspergillus flavus and to test whether aflatoxin production affects the H2O2 concentrations that the isolates could survive. Ten isolates were tested: NRRL3357 (+, A9 (+, AF13 (+, Tox4 (+, A1 (−, K49 (−, K54A (−, AF36 (−, and Aflaguard (−; and one A. parasiticus isolate, NRRL2999 (+. These isolates were cultured under a H2O2 gradient ranging from 0 to 50 mM in two different media, aflatoxin-conducive yeast extract-sucrose (YES and non-conducive yeast extract-peptone (YEP. Fungal growth was inhibited at a high H2O2 concentration, but specific isolates grew well at different H2O2 concentrations. Generally the toxigenic isolates tolerated higher concentrations than did atoxigenic isolates. Increasing H2O2 concentrations in the media resulted in elevated aflatoxin production in toxigenic isolates. In YEP media, the higher concentration of peptone (15% partially inactivated the H2O2 in the media. In the 1% peptone media, YEP did not affect the H2O2 concentrations that the isolates could survive in comparison with YES media, without aflatoxin production. It is interesting to note that the commercial biocontrol isolates, AF36 (−, and Aflaguard (−, survived at higher levels of stress than other atoxigenic isolates, suggesting that this testing method could potentially be of use in the selection of biocontrol isolates. Further studies will be needed to investigate the mechanisms behind the variability among isolates with regard to their degree of oxidative stress

Isolation and screening of azo dye decolorizing bacterial isolates from dye-contaminated textile wastewater

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Shahid Mahmood

2011-04-01

Full Text Available Azo dyes are released into wastewater streams without any pretreatment and pollute water and soilenvironments. To prevent contamination of our vulnerable resources, removal of these dye pollutants is of greatimportance. For this purpose, wastewater samples were collected from dye-contaminated sites of Faisalabad. About200 bacterial isolates were isolated through enrichment and then tested for their potential to remove RemazolBlack-B azo dye in liquid medium. Five bacterial isolates capable of degrading Remazol Black-B azo dye efficientlywere screened through experimentation on modified mineral salt medium. Isolate SS1 (collected from wastewater ofSupreme Textile Industry was able to completely remove the Remazol Black-B dye from the liquid medium in 18 h.Further, the isolate showed the best performance at the dye concentration of 100 mg L-1 medium (pH 7 and attemperature 35oC. Similarly, yeast extract proved to be the best carbon source for decolorization purpose. Theresults imply that the isolate SS1 could be used for the removal of the reactive dyes from textile effluents.

Antimicrobial susceptibility pattern of Brachyspira intermedia isolates from European layers.

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Verlinden, Marc; Boyen, Filip; Pasmans, Frank; Garmyn, An; Haesebrouck, Freddy; Martel, An

2011-09-01

A broth microdilution method was used to determine the antimicrobial susceptibility of 20 Brachyspira intermedia isolates obtained from different layer flocks in Belgium and The Netherlands between 2008 and 2010. The antimicrobial agents used were tylosin, tilmicosin, tiamulin, valnemulin, doxycycline, and lincomycin. The minimal inhibitory concentration (MIC) distribution patterns of tylosin, tilmicosin, lincomycin, and doxycycline were bimodal, demonstrating acquired resistance against doxycycline in three strains, against the macrolides in two strains, and against lincomycin in one strain. The MICs of tiamulin and valnemulin showed a monomodal distribution, but with tailing toward the higher MIC values, possibly suggesting low-level acquired resistance in six isolates. Sequencing revealed a G1058C mutation in the 16S rRNA gene in all doxycycline-resistant strains. The strain resistant to tylosin, tilmicosin, and lincomycin had an A2058T mutation in the 23S rRNA gene.

Seminational surveillance of fungemia in Denmark: notably high rates of fungemia and numbers of isolates with reduced azole susceptibility

DEFF Research Database (Denmark)

Arendrup, Maiken Cavling; Fuursted, Kurt; Gahrn-Hansen, Bente

2005-01-01

laboratory systems documented a continuous increase of candidemia cases since the early 1990s. For the 272 susceptibility-tested isolates, MICs of amphotericin B and caspofungin were within the limits expected for the species or genus. However, decreased azole susceptibility, defined as a fluconazole MIC...... of >8 microg/ml and/or itraconazole MIC of >0.125 microg/ml, was detected for 11 Candida isolates that were neither C. glabrata nor C. krusei. Including intrinsically resistant fungi, we detected decreased susceptibility to fluconazole and/or itraconazole in 87 (32%) current Danish bloodstream fungal...... isolates. We showed a continuous increase of fungemia in Denmark and an annual rate in 2003 to 2004 higher than in most other countries. The proportion of bloodstream fungal isolates with reduced susceptibility to fluconazole and/or itraconazole was also notably high....

THE LESSONIA NIGRESCENS SPECIES COMPLEX (LAMINARIALES, PHAEOPHYCEAE) SHOWS STRICT PARAPATRY AND COMPLETE REPRODUCTIVE ISOLATION IN A SECONDARY CONTACT ZONE(1).

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Tellier, Florence; Tapia, Javier; Faugeron, Sylvain; Destombe, Christophe; Valero, Myriam

2011-08-01

During secondary contact between phylogenetically closely related species (sibling species) having diverged in allopatry, the maintenance of species integrity depends on intrinsic and extrinsic reproductive barriers. In kelps (Phaeophyceae), the observations of hybrids in laboratory conditions suggest that reproductive isolation is incomplete. However, not all interspecific crosses are successful, and very few hybrids have been observed in nature, despite the co-occurrence of many kelp species in sympatry. This suggests that there are reproductive barriers that maintain species integrity. In this study, we characterized the fine genetic structure of a secondary contact zone to clarify the extent of reproductive isolation between two sister species. In Lessonia nigrescens Bory (Laminariales, Phaeophyta) species complex, two cryptic species have been recently found out from gene phylogenies, and-waiting for a formal taxonomic description-we used their geographic distribution to name them (northern and southern species). We studied 12 populations, distributed along 50 km of coastline, and employed two molecular approaches, assigning individuals to phylogenetic species according to a diagnostic mitochondrial marker (351 individuals analyzed) and quantifying interspecific gene flow with four microsatellite markers (248 individuals analyzed). No hybridization or introgression was revealed, indicating complete reproductive isolation in natural conditions. Unexpectedly, our study demonstrated that the two species were strictly segregated in space. This absence of co-occurrence along the contact zone can partially explain the lack of hybridization, raising new interesting questions as to the mechanisms that limit sympatry at small spatial scales. © 2011 Phycological Society of America.

A comparison of surface water natural organic matter in raw filtered water samples, XAD, and reverse osmosis isolates

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Maurice, P.A.; Pullin, M.J.; Cabaniss, S.E.; Zhou, Q.; Namjesnik-Dejanovic, K.; Aiken, G.R.

2002-01-01

This research compared raw filtered waters (RFWs), XAD resin isolates (XAD-8 and XAD-4), and reverse osmosis (RO) isolates of several surface water samples from McDonalds Branch, a small freshwater fen in the New Jersey Pine Barrens (USA). RO and XAD-8 are two of the most common techniques used to isolate natural organic matter (NOM) for studies of composition and reactivity; therefore, it is important to understand how the isolates differ from bulk (unisolated) samples and from one another. Although, any comparison between the isolation methods needs to consider that XAD-8 is specifically designed to isolate the humic fraction, whereas RO concentrates a broad range of organic matter and is not specific to humics. The comparison included for all samples: weight average molecular weight (Mw), number average molecular weight (Mn), polydispersity (??), absorbance at 280nm normalized to moles C (??280) (RFW and isolates); and for isolates only: elemental analysis, % carbon distribution by 13C NMR, and aqueous FTIR spectra. As expected, RO isolation gave higher yield of NOM than XAD-8, but also higher ash content, especially Si and S. Mw decreased in the order: RO>XAD-8>RFW>XAD-4. The Mw differences of isolates compared with RFW may be due to selective isolation (fractionation), or possibly in the case of RO to condensation or coagulation during isolation. 13C NMR results were roughly similar for the two methods, but the XAD-8 isolate was slightly higher in 'aromatic' C and the RO isolate was slightly higher in heteroaliphatic and carbonyl C. Infrared spectra indicated a higher carboxyl content for the XAD-8 isolates and a higher ester:carboxyl ratio for the RO isolates. The spectroscopic data thus are consistent with selective isolation of more hydrophobic compounds by XAD-8, and also with potential ester hydrolysis during that process, although further study is needed to determine whether ester hydrolysis does indeed occur. Researchers choosing between XAD and RO

Biomineralization processes of calcite induced by bacteria isolated from marine sediments.

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Wei, Shiping; Cui, Hongpeng; Jiang, Zhenglong; Liu, Hao; He, Hao; Fang, Nianqiao

2015-06-01

Biomineralization is a known natural phenomenon associated with a wide range of bacterial species. Bacterial-induced calcium carbonate precipitation by marine isolates was investigated in this study. Three genera of ureolytic bacteria, Sporosarcina sp., Bacillus sp. and Brevundimonas sp. were observed to precipitate calcium carbonate minerals. Of these species, Sporosarcina sp. dominated the cultured isolates. B. lentus CP28 generated higher urease activity and facilitated more efficient precipitation of calcium carbonate at 3.24 ± 0.25 × 10(-4) mg/cell. X-ray diffraction indicated that the dominant calcium carbonate phase was calcite. Scanning electron microscopy showed that morphologies of the minerals were dominated by cubic, rhombic and polygonal plate-like crystals. The dynamic process of microbial calcium carbonate precipitation revealed that B. lentus CP28 precipitated calcite crystals through the enzymatic hydrolysis of urea, and that when ammonium ion concentrations reached 746 mM and the pH reached 9.6, that favored calcite precipitation at a higher level of 96 mg/L. The results of this research provide evidence that a variety of marine bacteria can induce calcium carbonate precipitation, and may influence the marine carbonate cycle in natural environments.

Isolation and characterization of plant growth promoting endophytic diazotrophic bacteria from Korean rice cultivars.

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Ji, Sang Hye; Gururani, Mayank Anand; Chun, Se-Chul

2014-01-20

We have isolated 576 endophytic bacteria from the leaves, stems, and roots of 10 rice cultivars and identified 12 of them as diazotrophic bacteria using a specific primer set of nif gene. Through 16S rDNA sequence analysis, nifH genes were confirmed in the two species of Penibacillus, three species of Microbacterium, three Bacillus species, and four species of Klebsiella. Rice seeds treated with these plant growth-promoting bacteria (PGPB) showed improved plant growth, increased height and dry weight and antagonistic effects against fungal pathogens. In addition, auxin and siderophore producing ability, and phosphate solubilizing activity were studied for the possible mechanisms of plant growth promotion. Among 12 isolates tested, 10 strains have shown higher auxin producing activity, 6 isolates were confirmed as strains with high siderophore producing activity while 4 isolates turned out to have high phosphate-solubilizing activity. These results strongly suggest that the endophytic diazotrophic bacteria characterized in this study could be successfully used to promote plant growth and inducing fungal resistance in plants. Copyright © 2013 Elsevier GmbH. All rights reserved.

Biofilm production by clinical isolates of Pseudomonas aeruginosa and structural changes in LasR protein of isolates non biofilm-producing

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Jailton Lobo da Costa Lima

2018-03-01

Full Text Available Introduction: Biofilm production is an important mechanism for the survival of Pseudomonas aeruginosa and its relationship with antimicrobial resistance represents a challenge for patient therapeutics. P. aeruginosa is an opportunistic pathogen frequently associated to nosocomial infections, especially in imunocompromised hosts. Objectives: Analyze the phenotypic biofilm production in P. aeruginosa isolates, describe clonal profiles, and analyze quorum sensing (QS genes and the occurrence of mutations in the LasR protein of non-biofilm producing isolates. Methods: Isolates were tested for biofilm production by measuring cells adherence to the microtiter plates. Clonal profile analysis was carried out through ERIC-PCR, QS genes were by specific PCR. Results: The results showed that 77.5% of the isolates were considered biofilm producers. The results of genotyping showed 38 distinct genetic profiles. As for the occurrence of the genes, 100% of the isolates presented the lasR, rhlI and rhlR genes, and 97.5%, presented the lasI gene. In this study nine isolates were not biofilm producers. However, all presented the QS genes. Amplicons related to genes were sequenced in three of the nine non-biofilm-producing isolates (all presenting different genetic similarity profile and aligned to the sequences of those genes in P. aeruginosa strain PAO1 (standard biofilm-producing strain. Alignment analysis showed an insertion of three nucleotides (T, C and G causing the addition of an amino acid valine in the sequence of the LasR protein, in position 53. Conclusion: The modeling of the resulting LasR protein showed a conformational change in its structure, suggesting that this might be the reason why these isolates are unable to produce biofilm. Keywords: Pseudomonas aeruginosa, Biofilm, Multiresistance, Quorum sensing (QS

Acid-producing capacity from sugars and sugar alcohols among Lactobacillus isolates collected in connection with radiation therapy.

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Almståhl, Annica; Rudbäck, Helena; Basic, Amina; Carlén, Anette; Alstad, Torgny

2017-12-01

To investigate the acid-producing capacity from sugars and sugar alcohols of oral Lactobacillus collected in connection with radiation therapy (RT) to the head and neck region. Lactobacillus were collected from the tongue, buccal mucosa and supragingival plaque in 24 patients before, during, and after RT. The acid-producing capacity of Lactobacillus isolates (n=211) was analyzed using a colorimetric fermentation test in microtiter plates. Solutions containing 2% sugars (sucrose, glucose, fructose, lactose) or sugar-alcohols (sorbitol and xylitol) were used. After 24h of incubation, bacterial acid-producing capacity was determined as strong (pH6). Data regarding intake frequency of sugar-rich products and products with sugar-alcohols was collected. The highest acid-producing capacity using the sugars was seen for isolates collected during RT. Sorbitol was fermented to a higher extent during and post RT, especially among isolates from plaque. Lactobacillus fermenting xylitol showed the highest acid-producing capacity during RT (psugar-rich products or sugar-alcohol containing products and Lactobacillus acid-producing capacity, were found. The results suggest that Lactobacillus isolates, collected from the tongue, buccal mucosa and supragingival plaque, have a higher acid-producing capacity using sugars and sugar-alcohols during RT than one year post RT. Copyright © 2017 Elsevier Ltd. All rights reserved.

Isolated Horizon, Killing Horizon and Event Horizon

OpenAIRE

Date, G.

2001-01-01

We consider space-times which in addition to admitting an isolated horizon also admit Killing horizons with or without an event horizon. We show that an isolated horizon is a Killing horizon provided either (1) it admits a stationary neighbourhood or (2) it admits a neighbourhood with two independent, commuting Killing vectors. A Killing horizon is always an isolated horizon. For the case when an event horizon is definable, all conceivable relative locations of isolated horizon and event hori...

Comparative characterisation of the biofilm-production abilities of Staphylococcus epidermidis isolated from human skin and platelet concentrates.

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Taha, Mariam; Kohnen, Carissa; Mallya, Shruti; Kou, Yuntong; Zapata, Adriana; Ramirez-Arcos, Sandra

2018-02-01

Staphylococcus epidermidis is the predominant contaminant of platelet concentrates (PCs), a blood product used to treat patients with platelet deficiencies. This microorganism is able to form surface-attached aggregates (biofilms) in human skin. Herein, the abundance of S. epidermidis biofilm-producers in contaminated PCs compared to skin isolates was explored. Furthermore, the potential positive selection of S. epidermidis biofilm-producers during the blood donation process and PC manufacturing was investigated. Twenty-four S. epidermidis isolates obtained from contaminated PCs and 48 S. epidermidis isolates obtained from the venipuncture area of human volunteers were compared for their ability to form biofilms in laboratory media and in PCs using a semi quantitative crystal violet assay. Also, the presence of the biofilm-associated icaA and icaD genes was assessed by PCR-amplification.Results/Key findings.Biofilm production in laboratory media showed a higher number of S. epidermidis biofilm-producers in the skin-derived group (43.7 %) compared to the PC-derived isolates (25 %). However, all skin and PC isolates formed biofilms in PCs. The prevalence of ica-positive biofilm-producer isolates was similar in PC and skin isolates (16.6 and 18.8 %, respectively). In contrast, the abundance of ica-negative biofilm-producers was lower in PC isolates compared to skin isolates (8.3 vs 25 %, respectively). Positive selection of S. epidermidis biofilm-producers during blood donation and PC manufacturing was not observed. Interestingly, ica-negative biofilm-producers seem to be negatively affected by skin disinfection, blood processing and PC storage. Furthermore, this study shows that S. epidermidis adopts a biofilm-forming phenotype in PCs regardless of its genetic background or origin.

Social Isolation, Depression, and Psychological Distress Among Older Adults.

Science.gov (United States)

Taylor, Harry Owen; Taylor, Robert Joseph; Nguyen, Ann W; Chatters, Linda

2018-02-01

To investigate the impact of objective and subjective social isolation from extended family members and friends on depressive symptoms and psychological distress among a national sample of older adults. Data for older adults (55 years and above) from the National Survey of American Life ( N = 1,439) were used to assess level of objective social isolation and subjective social isolation and to test regression models examining their impact on depressive symptoms (Center for Epidemiologic Studies Depression [CES-D] Scale) and psychological distress (Kessler 6 [K6] Scale). The majority of respondents were not socially isolated from family or friends; 5% were objectively isolated from family and friends, and less than 1% were subjectively isolated from family and friends. Regression analyses using both social isolation measures indicated that objective social isolation was unrelated to depressive symptoms and psychological distress. However, subjective social isolation from both family and friends and from friends only was associated with more depressive symptoms, and subjective social isolation from friends only was associated with higher levels of psychological distress. Assessments of social isolation among older populations should account for both subjective and objective dimensions, as well as both family and friend social networks. Social isolation from friends is an important, but understudied, issue that has significant consequences for older adult mental health.

Loneliness, Social Isolation, and Cardiovascular Health.

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Xia, Ning; Li, Huige

2018-03-20

Social and demographic changes have led to an increased prevalence of loneliness and social isolation in modern society. Recent Advances: Population-based studies have demonstrated that both objective social isolation and the perception of social isolation (loneliness) are correlated with a higher risk of mortality and that both are clearly risk factors for cardiovascular disease (CVD). Lonely individuals have increased peripheral vascular resistance and elevated blood pressure. Socially isolated animals develop more atherosclerosis than those housed in groups. Molecular mechanisms responsible for the increased cardiovascular risk are poorly understood. In recent reports, loneliness and social stress were associated with activation of the hypothalamic-pituitary-adrenocortical axis and the sympathetic nervous system. Repeated and chronic social stress leads to glucocorticoid resistance, enhanced myelopoiesis, upregulated proinflammatory gene expression, and oxidative stress. However, the causal role of these mechanisms in the development of loneliness-associated CVD remains unclear. Elucidation of the molecular mechanisms of how CVD is induced by loneliness and social isolation requires additional studies. Understanding of the pathomechanisms is essential for the development of therapeutic strategies to prevent the detrimental effects of social stress on health. Antioxid. Redox Signal. 28, 837-851.

Comparison of Enterococcus faecium and Enterococcus faecalis Strains isolated from water and clinical samples: antimicrobial susceptibility and genetic relationships.

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Castillo-Rojas, Gonzalo; Mazari-Hiríart, Marisa; Ponce de León, Sergio; Amieva-Fernández, Rosa I; Agis-Juárez, Raúl A; Huebner, Johannes; López-Vidal, Yolanda

2013-01-01

Enterococci are part of the normal intestinal flora in a large number of mammals, and these microbes are currently used as indicators of fecal contamination in water and food for human consumption. These organisms are considered one of the primary causes of nosocomial and environmental infections due to their ability to survive in the environment and to their intrinsic resistance to antimicrobials. The aims of this study were to determine the biochemical patterns and antimicrobial susceptibilities of Enterococcus faecalis and E. faecium isolates from clinical samples and from water (groundwater, water from the Xochimilco wetland, and treated water from the Mexico City Metropolitan Area) and to determine the genetic relationships among these isolates. A total of 121 enterococcus strains were studied; 31 and 90 strains were isolated from clinical samples and water (groundwater, water from the Xochimilco wetland, and water for agricultural irrigation), respectively. Identification to the species level was performed using a multiplex PCR assay, and antimicrobial profiles were obtained using a commercial kit. Twenty-eight strains were analyzed by pulsed-field gel electrophoresis (PFGE). E. faecium strains isolated from water showed an atypical biochemical pattern. The clinical isolates showed higher resistance to antibiotics than those from water. Both the enterococci isolated from humans, and those isolated from water showed high genetic diversity according to the PFGE analysis, although some strains seemed to be closely related. In conclusion, enterococci isolated from humans and water are genetically different. However, water represents a potential route of transmission to the community and a source of antimicrobial resistance genes that may be readily transmitted to other, different bacterial species.

Comparison of Enterococcus faecium and Enterococcus faecalis Strains isolated from water and clinical samples: antimicrobial susceptibility and genetic relationships.

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Gonzalo Castillo-Rojas

Full Text Available Enterococci are part of the normal intestinal flora in a large number of mammals, and these microbes are currently used as indicators of fecal contamination in water and food for human consumption. These organisms are considered one of the primary causes of nosocomial and environmental infections due to their ability to survive in the environment and to their intrinsic resistance to antimicrobials. The aims of this study were to determine the biochemical patterns and antimicrobial susceptibilities of Enterococcus faecalis and E. faecium isolates from clinical samples and from water (groundwater, water from the Xochimilco wetland, and treated water from the Mexico City Metropolitan Area and to determine the genetic relationships among these isolates. A total of 121 enterococcus strains were studied; 31 and 90 strains were isolated from clinical samples and water (groundwater, water from the Xochimilco wetland, and water for agricultural irrigation, respectively. Identification to the species level was performed using a multiplex PCR assay, and antimicrobial profiles were obtained using a commercial kit. Twenty-eight strains were analyzed by pulsed-field gel electrophoresis (PFGE. E. faecium strains isolated from water showed an atypical biochemical pattern. The clinical isolates showed higher resistance to antibiotics than those from water. Both the enterococci isolated from humans, and those isolated from water showed high genetic diversity according to the PFGE analysis, although some strains seemed to be closely related. In conclusion, enterococci isolated from humans and water are genetically different. However, water represents a potential route of transmission to the community and a source of antimicrobial resistance genes that may be readily transmitted to other, different bacterial species.

Comparative Genome Analyses of Streptococcus suis Isolates from Endocarditis Demonstrate Persistence of Dual Phenotypic Clones.

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Tohya, Mari; Watanabe, Takayasu; Maruyama, Fumito; Arai, Sakura; Ota, Atsushi; Athey, Taryn B T; Fittipaldi, Nahuel; Nakagawa, Ichiro; Sekizaki, Tsutomu

2016-01-01

Many bacterial species coexist in the same niche as heterogeneous clones with different phenotypes; however, understanding of infectious diseases by polyphenotypic bacteria is still limited. In the present study, encapsulation in isolates of the porcine pathogen Streptococcus suis from persistent endocarditis lesions was examined. Coexistence of both encapsulated and unencapsulated S. suis isolates was found in 26 out of 59 endocarditis samples. The isolates were serotype 2, and belonged to two different sequence types (STs), ST1 and ST28. The genomes of each of the 26 pairs of encapsulated and unencapsulated isolates from the 26 samples were sequenced. The data showed that each pair of isolates had one or more unique nonsynonymous mutations in the cps gene, and the encapsulated and unencapsulated isolates from the same samples were closest to each other. Pairwise comparisons of the sequences of cps genes in 7 pairs of encapsulated and unencapsulated isolates identified insertion/deletions (indels) ranging from one to 104 bp in different cps genes of unencapsulated isolates. Capsule expression was restored in a subset of unencapsulated isolates by complementation in trans with cps expression vectors. Examination of gene content common to isolates indicated that mutation frequency was higher in ST28 pairs than in ST1 pairs. Genes within mobile genetic elements were mutation hot spots among ST28 isolates. Taken all together, our results demonstrate the coexistence of dual phenotype (encapsulated and unencapsulated) bacterial clones and suggest that the dual phenotypes arose independently in each farm by means of spontaneous mutations in cps genes.

Comparative Genome Analyses of Streptococcus suis Isolates from Endocarditis Demonstrate Persistence of Dual Phenotypic Clones.

Directory of Open Access Journals (Sweden)

Mari Tohya

Full Text Available Many bacterial species coexist in the same niche as heterogeneous clones with different phenotypes; however, understanding of infectious diseases by polyphenotypic bacteria is still limited. In the present study, encapsulation in isolates of the porcine pathogen Streptococcus suis from persistent endocarditis lesions was examined. Coexistence of both encapsulated and unencapsulated S. suis isolates was found in 26 out of 59 endocarditis samples. The isolates were serotype 2, and belonged to two different sequence types (STs, ST1 and ST28. The genomes of each of the 26 pairs of encapsulated and unencapsulated isolates from the 26 samples were sequenced. The data showed that each pair of isolates had one or more unique nonsynonymous mutations in the cps gene, and the encapsulated and unencapsulated isolates from the same samples were closest to each other. Pairwise comparisons of the sequences of cps genes in 7 pairs of encapsulated and unencapsulated isolates identified insertion/deletions (indels ranging from one to 104 bp in different cps genes of unencapsulated isolates. Capsule expression was restored in a subset of unencapsulated isolates by complementation in trans with cps expression vectors. Examination of gene content common to isolates indicated that mutation frequency was higher in ST28 pairs than in ST1 pairs. Genes within mobile genetic elements were mutation hot spots among ST28 isolates. Taken all together, our results demonstrate the coexistence of dual phenotype (encapsulated and unencapsulated bacterial clones and suggest that the dual phenotypes arose independently in each farm by means of spontaneous mutations in cps genes.

Comparative Genome Analyses of Streptococcus suis Isolates from Endocarditis Demonstrate Persistence of Dual Phenotypic Clones

Science.gov (United States)

Tohya, Mari; Watanabe, Takayasu; Maruyama, Fumito; Arai, Sakura; Ota, Atsushi; Athey, Taryn B. T.; Fittipaldi, Nahuel; Nakagawa, Ichiro; Sekizaki, Tsutomu

2016-01-01

Many bacterial species coexist in the same niche as heterogeneous clones with different phenotypes; however, understanding of infectious diseases by polyphenotypic bacteria is still limited. In the present study, encapsulation in isolates of the porcine pathogen Streptococcus suis from persistent endocarditis lesions was examined. Coexistence of both encapsulated and unencapsulated S. suis isolates was found in 26 out of 59 endocarditis samples. The isolates were serotype 2, and belonged to two different sequence types (STs), ST1 and ST28. The genomes of each of the 26 pairs of encapsulated and unencapsulated isolates from the 26 samples were sequenced. The data showed that each pair of isolates had one or more unique nonsynonymous mutations in the cps gene, and the encapsulated and unencapsulated isolates from the same samples were closest to each other. Pairwise comparisons of the sequences of cps genes in 7 pairs of encapsulated and unencapsulated isolates identified insertion/deletions (indels) ranging from one to 104 bp in different cps genes of unencapsulated isolates. Capsule expression was restored in a subset of unencapsulated isolates by complementation in trans with cps expression vectors. Examination of gene content common to isolates indicated that mutation frequency was higher in ST28 pairs than in ST1 pairs. Genes within mobile genetic elements were mutation hot spots among ST28 isolates. Taken all together, our results demonstrate the coexistence of dual phenotype (encapsulated and unencapsulated) bacterial clones and suggest that the dual phenotypes arose independently in each farm by means of spontaneous mutations in cps genes. PMID:27433935

Comparison of MKP and BSK-H media for the cultivation and isolation of Borrelia burgdorferi sensu lato.

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Eva Ružić-Sabljić

Full Text Available The isolation of B. burgdorferi sensu lato requires the use of complex cultivation media. The aim of the study was to compare the usefulness of BSK-H (a commercial medium produced by HiMedia, India and MKP medium. MKP and BSK-H media were prepared in accordance with the relevant protocols. Borrelia strains and skin culture biopsies were simultaneously inoculated into both media, incubated and checked for growth. Borrelial growth characteristics, isolation rates and characteristics of the isolated borreliae were analysed and compared. Initially, numbers of spirochaetes were higher in BSK-H than in MKP; however, in comparison with MKP, the strains subcultured in BSK-H medium were more frequently irregular, thin and non-motile, and rapidly died. In addition, the borrelial isolation rate from erythema migrans skin samples was higher in MKP than in BSK-H medium (108/171, 63.2% versus 70/171, 40.9%; p<0.0001. The far most frequently isolated species was Borrelia afzelii (92.9% and 97.2% strains isolated from BSK-H and MKP, respectively. Comparison of strains cultured from individual patients in both media showed differences in plasmid contents in 9/46 (19.6% strain pairs, and protein profiles differed in 30/43 (69.8% strain pairs, most often in the expression of OspC (in 27/28 patients OspC was expressed only in strains growing in MKP. BSK-H medium supports the growth of borrelial strains but MKP is superior with regard to the isolation rate, morphology and motility of strains. BSK-H medium supports fast initial growth of borreliae but this is followed by rapid deformation and death of the spirochaetes.

Osmotically and thermally isolated forward osmosis-membrane distillation (fo-md) integrated module for water treatment applications

KAUST Repository

Ghaffour, Noreddine

2016-09-01

An integrated forward osmosis-membrane distillation (FO-MD) module and systems and methods incorporating the module is disclosed providing higher efficiencies and using less energy. The FO-MD module is osmotically and thermally isolated. The isolation can prevent mixing of FO draw solution/FO permeate and MD feed, and minimize dilution of FO draw solution and cooling of MD feed. The module provides MD feed solution and FO draw solution streams that flow in the same module but are separated by an isolation barrier. The osmotically and thermally isolated FO-MD integrated module, systems and methods offer higher driving forces of both FO and MD processes, higher recovery, and wider application than previously proposed hybrid FO- MD systems.

Osmotically and thermally isolated forward osmosis-membrane distillation (fo-md) integrated module for water treatment applications

KAUST Repository

Ghaffour, NorEddine; Francis, Lijo; Li, Zhenyu; Valladares, Rodrigo; Alsaadi, Ahmad S.; Ghdaib, Muhannad Abu; Amy, Gary L.

2016-01-01

An integrated forward osmosis-membrane distillation (FO-MD) module and systems and methods incorporating the module is disclosed providing higher efficiencies and using less energy. The FO-MD module is osmotically and thermally isolated. The isolation can prevent mixing of FO draw solution/FO permeate and MD feed, and minimize dilution of FO draw solution and cooling of MD feed. The module provides MD feed solution and FO draw solution streams that flow in the same module but are separated by an isolation barrier. The osmotically and thermally isolated FO-MD integrated module, systems and methods offer higher driving forces of both FO and MD processes, higher recovery, and wider application than previously proposed hybrid FO- MD systems.

Effect of drying methods on the structure, thermo and functional properties of fenugreek (Trigonella foenum graecum) protein isolate.

Science.gov (United States)

Feyzi, Samira; Varidi, Mehdi; Zare, Fatemeh; Varidi, Mohammad Javad

2018-03-01

Different drying methods due to protein denaturation could alter the functional properties of proteins, as well as their structure. So, this study focused on the effect of different drying methods on amino acid content, thermo and functional properties, and protein structure of fenugreek protein isolate. Freeze and spray drying methods resulted in comparable protein solubility, dynamic surface and interfacial tensions, foaming and emulsifying properties except for emulsion stability. Vacuum oven drying promoted emulsion stability, surface hydrophobicity and viscosity of fenugreek protein isolate at the expanse of its protein solubility. Vacuum oven process caused a higher level of Maillard reaction followed by the spray drying process, which was confirmed by the lower amount of lysine content and less lightness, also more browning intensity. ΔH of fenugreek protein isolates was higher than soy protein isolate, which confirmed the presence of more ordered structures. Also, the bands which are attributed to the α-helix structures in the FTIR spectrum were in the shorter wave number region for freeze and spray dried fenugreek protein isolates that show more possibility of such structures. This research suggests that any drying method must be conducted in its gentle state in order to sustain native structure of proteins and promote their functionalities. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Biofilm Formation and Disinfectant Susceptibility of Persistent and Nonpersistent Listeria monocytogenes Isolates from Gorgonzola Cheese Processing Plants.

Science.gov (United States)

Costa, Annalisa; Bertolotti, Luigi; Brito, Luisa; Civera, Tiziana

2016-11-01

The aim of this study was to investigate whether the biofilm-forming ability and/or the disinfectant susceptibility accounted for the persistence of Listeria monocytogenes in Gorgonzola cheese processing plants. For this purpose, a set of 16 L. monocytogenes isolates collected in the 2004-2007 period was analyzed, including 11 persistent isolates collected in different years, within the collection period, and displaying identical or highly correlated pulsotypes. The evaluation of biofilm-forming ability was assessed using crystal violet (CV) staining and the enumeration of viable cells on stainless steel coupons (SSC). Absorbance values obtained with CV staining for persistent and nonpersistent isolates were not significantly different (rm-ANOVA p > 0.05) and the cell counts from nonpersistent isolates showed to be higher compared with persistent isolates (rm-ANOVA p biofilms on SSC, grown in nutrient-rich (dirty) and limiting (clean) conditions using acid acetic-hydrogen peroxide (P3) and acid citric-hydrogen peroxide (MS) commercial disinfectants. The treatment was considered effective when a 4 Log reduction in viable cell count was observed. The Log reductions of persistent and nonpersistent isolates, obtained with both the assays in clean and dirty conditions, were compared and no significant differences were detected (rm-ANOVA p > 0.05). A greater influence of organic matter on MS could explain why P3 was efficient in reducing to effective levels the majority of the isolates at the lowest concentration suggested by the manufacturer (0.2% [v/v]), while the same purpose required a higher concentration (1% [v/v]) of MS. In conclusion, our results demonstrate that the persistence of these isolates in Gorgonzola cheese processing plants was linked neither to the biofilm-forming ability nor to their susceptibility to hydrogen peroxide-based disinfectants; therefore, other factors should contribute to the persistent colonization of the dairies.

Social isolation after spinal cord injury: Indicators from the Longitudinal Aging Study.

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Newman, Susan D; Li, Chao; Krause, James S

2016-11-01

The purpose of this study was to develop and test a conceptual model of social isolation, incorporating social disconnectedness (objective measures) and perceived isolation (subjective appraisals) in an aging sample of participants with spinal cord injury (SCI). The study used cross-sectional data from 768 participants from the most recent administration of the SCI Longitudinal Aging Study, which was initiated in 1973. Measures included the revised version of the Life Situation Questionnaire, items from the Craig Handicap Assessment Reporting Technique, and the Patient Reported Outcomes Measurement Information System. Indicators of social isolation were combined into scales assessing social disconnectedness and perceived isolation. We tested the hypothesized model of social isolation, including both social disconnectedness and perceived isolation, after SCI using structural equation modeling. Results of structural equation modeling indicated good fit between the hypothesized model and data (root-mean-square error of approximation = 0.073, 90% confidence interval [0.070, 0.075]; comparative fit index = 0.949; Tucker Lewis Index = 0.946). Perceived isolation was significantly related with social disconnectedness (standardized coefficient [r] = .610). Several exogenous factors were significantly related to social disconnectedness and perceived isolation. Older participants were more likely to report lower levels of perceived isolation. Time since injury demonstrated an inverse relationship with both social disconnectedness and perceived isolation. Higher level and severity of injury were associated with higher levels of social disconnectedness. Our study establishes a stable model of social isolation to guide future research exploring the effect of social isolation on health after SCI. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A rapid, efficient, and economic device and method for the isolation and purification of mouse islet cells.

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Yin Zongyi

Full Text Available Rapid, efficient, and economic method for the isolation and purification of islets has been pursued by numerous islet-related researchers. In this study, we compared the advantages and disadvantages of our developed patented method with those of commonly used conventional methods (Ficoll-400, 1077, and handpicking methods. Cell viability was assayed using Trypan blue, cell purity and yield were assayed using diphenylthiocarbazone, and islet function was assayed using acridine orange/ethidium bromide staining and enzyme-linked immunosorbent assay-glucose stimulation testing 4 days after cultivation. The results showed that our islet isolation and purification method required 12 ± 3 min, which was significantly shorter than the time required in Ficoll-400, 1077, and HPU groups (34 ± 3, 41 ± 4, and 30 ± 4 min, respectively; P 1000 islets. In summary, the MCT method is a rapid, efficient, and economic method for isolating and purifying murine islet cell clumps. This method overcomes some of the shortcomings of conventional methods, showing a relatively higher quality and yield of islets within a shorter duration at a lower cost. Therefore, the current method provides researchers with an alternative option for islet isolation and should be widely generalized.

EFFECT OF HIGHLY ACTIVE ANTIRETROVIRAL THERAPY ON VAGINAL Candida spp. ISOLATION IN HIV-INFECTED COMPARED TO HIV-UNINFECTED WOMEN

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Silvia de Souza Dantas ALCZUK

2015-04-01

Full Text Available Vulvovaginal candidiasis (VVC in HIV-infected women contributed to the impairment of their quality of life. The aim of this study was to evaluate the effect of highly active antiretroviral therapy (HAART use on the vaginal Candida spp. isolation in HIV-infected compared to HIV-uninfected women. This cross-sectional study included 178 HIV-infected (HIV group and 200 HIV-uninfected women (control that were studied at the Specialized Assistance Service (SAE for sexually transmitted diseases (STD/AIDS of the city of Maringá, Brazil, from April 1 to October 30, 2011. The yeasts were isolated and identified by phenotypic and molecular methods. The in vitro antifungal susceptibility to fluconazole, itraconazole, nystatin and amphotericin B was tested by the reference microdilution method. Higher frequencies of total vaginal Candida spp. isolation were found in the HIV-infected group than in the control group. However, both groups showed a similar frequency of colonization and VVC. Although C. albicans was the most frequent and sensitive to azolics and polyenes in both HIV-infected and uninfected women, the emerging resistance of C. glabrata to amphotericin B in the HIV-infected women was observed. Although higher frequency of vaginal Candida spp. isolation had been observed in the HIV-infected than in HIV-uninfected women, colonization and VVC showed similar frequency in both groups, indicating that HAART appears to protect against vaginal colonization and VVC.

Isolation, identification and anti-candidal activity of filamentous fungi from Saudi Arabia soil

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Nouf M. Al-Enazi

2018-02-01

Full Text Available Ten fungal strains; namely, Penicillium melinii, Petriella setifera, Aspergillus pseudo-niger, Alternaria chlamydospora, Pythium nayoroense, Phoma glomerata, Mucor ramosissimus, Mucor racemosus, Fusarium chlamydosporum and Rhizopus azygosporus were isolated from soil. The extra- and intra-cellular extracts of the fungal strains grown on malt extract and yeast-extract sucrose media were screened for their anticandidal activity against different clinically-isolated Candida species. Most of the fungal extracts showed activity against different Candida species. However, the fungal strains grew on malt extract showed greater activities than those grew on yeast extract sucrose media. The activity of the intracellular was higher than the extracellular metabolites. All fungal extracts (extra and intra were similar in chemical constituent; they contained carbohydrates and/or glycosides, unsaturated sterols and/or triterpens, tannins and traces of coumarins. Alkaloids, flavonoids, saponins, anthraquinones and cardenolides were no detected. The intra-cellular extracts contained more compounds than the extra-cellular extracts.

Dental Pulp Cells Isolated from Teeth with Superficial Caries Retain an Inflammatory Phenotype and Display an Enhanced Matrix Mineralization Potential

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Reem El-Gendy

2017-04-01

Full Text Available We have isolated dental pulp cells (DPCs from three healthy (hDPCs and three carious (cDPCs donors and shown that compared to hDPCs cells isolated from superficial carious lesions show higher clonogenic potential; show an equivalent proportion of cells with putative stem cell surface markers; show enhanced matrix mineralization capability; have enhanced angiogenic marker expression and retain the inflammatory phenotype in vitro characteristic of superficial caries lesions in vivo. Our findings suggest that cDPCs may be used for further investigation of the cross talk between inflammatory, angiogenic and mineralization pathways in repair of carious pulp. In addition cells derived from carious pulps (almost always discarded may have potential for future applications in mineralized tissue repair and regeneration.

Molecular and in vitro Characterization of Field Isolates of Bovine Herpesvirus-1

Institute of Scientific and Technical Information of China (English)

Julian Ruiz-Saenz; Jairo Jaime; Gloria Ramirez; Victor Vera

2012-01-01

Bovine Herpesvirus-1 (BoHV-1) is distributed worldwide and is a major pathogen in cattle,being the causal agent of a variety of clinical syndromes.The aim of this study was to isolate and to characterize (molecular and biological characterization) BoHV- 1 from 29 immunosuppressed animals.It was possible to obtain 18 isolates,each from a different animal,such as from the respiratory and reproductive tracts.In some cases the cytopathic effect was visible 12 hours post-inoculation,and became characteristic after 36-48 hours.Biological characteristics were evaluated and compared with Iowa and Colorado-1 reference strains,and differences were found in plaque size,virus titer measured by TCID50 and PFU/mL,and one step virus curves.These results showed that some isolates had a highly virulent-like behavior in vitro,compared to the reference strains,with shorter eclipse periods,faster release of virus into the supematants,and higher burst size and viral titer.There were no differences in glycoprotein expression of BoHV-1 isolates,measured by Western blot on monolayers.Moreover,using restriction endonucleases analysis,most of the viruses were confirmed as BoHV-1.1 and just one of them was confirmed as BoHV-1.2a subtype.These findings suggest that some wild-type BoHV-1 isolates could be useful as seeds to develop new monovalent vaccines.

The isolated anatase for dye sensitized solar cell

Energy Technology Data Exchange (ETDEWEB)

Ilmi, Irfan, E-mail: irfan.ilmi149@gmail.com [Postgraduate Program, Department of Chemistry, Universitas Gadjah Mada, Yogyakarta 55281 Indonesia (Indonesia); Functional Coating Materials Research Group, Department of Chemistry, Universitas Gadjah Mada, Yogyakarta 55281 Indonesia (Indonesia); Kartin, Indriana; Suyanta [Functional Coating Materials Research Group, Department of Chemistry, Universitas Gadjah Mada, Yogyakarta 55281 Indonesia (Indonesia); Department of Chemistry,Universitas Gadjah Mada, Yogyakarta 55281 Indonesia (Indonesia); Ohtani, Bunsho; Wang, Kunlei [Graduate School of Environmental and Earth Science, Hokkaido University Japan (Japan)

2015-09-30

The isolation of crystallite anatase from commercial TiO{sub 2} P25 Degussa was investigated. The aim of this research was to study of isolated anatase based DSSC as an effort to develop industrial DSSC. The crystal phase, crystallite size and crystal shape both of original P25 and isolated anatase were characterized by XRD and TEM. By observing DSSC parameters such as FF, Jsc and Voc resulted in cell test, the efficiency of samples based DSSC was known. The isolation of anatase crystal was done by dissolving P25 in ammonia catalyzed hydrogen peroxide solution for 15 hours followed by washing and drying. DSSC cell performance was evaluated by applying the isolated anantase and original P25 as photoanode in the Gratzel cell system. The observation of cell efficiency was measured under 100 mW /cm{sup 2} with active area 1.5 cm{sup 2}. X-ray diffraction pattern showed obviously that no rutile contaminant in produced isolated anatase. TEM image shows typical anatase crystal with the particle size 21 nm. Surface area measurement exhibits that surface area of isolated anatase was 64.7m{sup 2}/g. I-V measurement showed that the efficiency of anatase based cell and P25 based cell is 0.79% and 0.51% respectively.

Adsorption of pharmaceuticals onto isolated polyamide active layer of NF/RO membranes.

Science.gov (United States)

Liu, Yan-Ling; Wang, Xiao-Mao; Yang, Hong-Wei; Xie, Yuefeng F

2018-06-01

Adsorption of trace organic compounds (TrOCs) onto the membrane materials has a great impact on their rejection by nanofiltration (NF) and reverse osmosis (RO) membranes. This study aimed to investigate the difference in adsorption of various pharmaceuticals (PhACs) onto different NF/RO membranes and to demonstrate the necessity of isolating the polyamide (PA) active layer from the polysulfone (PS) support layer for adsorption characterization and quantification. Both the isolated PA layers and the PA+PS layers of NF90 and ESPA1 membranes were used to conduct static adsorption tests. Results showed that apparent differences existed between the PA layer and the PA+PS layer in the adsorption capacity of PhACs as well as the time necessary to reach the adsorption equilibrium. PhACs with different physicochemical properties could be adsorbed to different extents by the isolated PA layer, which was mainly attributed to electrostatic attraction/repulsion and hydrophobic interactions. The PA layer of ESPA1 exhibited apparently higher adsorption capacities for the positively charged PhACs and similar adsorption capacities for the neutral PhACs although it had significantly less total interfacial area (per unit membrane surface area) for adsorption compared to the PA layer of NF90. The higher affinity of the PA layer of ESPA1 for the PhACs could be due to its higher capacity of forming hydrogen bonds with PhACs resulted from the modified chemistry with more -OH groups. This study provides a novel approach to determining the TrOC adsorption onto the active layer of membranes for the ease of investigating adsorption mechanisms. Copyright © 2018 Elsevier Ltd. All rights reserved.

Comparative studies on mitochondria isolated from neuron-enriched and glia-enriched fractions of rabbit and beef brain.

Science.gov (United States)

Hamberger, A; Blomstrand, C; Lehninger, A L

1970-05-01

Fractions enriched in neuronal and glial cells were obtained from dispersions of whole beef brain and rabbit cerebral cortex by large-scale density gradient centrifugation procedures. The fractions were characterized by appropriate microscopic observation. Mitochondria were then isolated from these fractions by differential centrifugation of their homogenates. The two different types of mitochondria were characterized with respect to certain enzyme activities, respiratory rate, rate of protein synthesis, and their buoyant density in sucrose gradients. The mitochondria from the neuron-enriched fraction were distinguished by a higher rate of incorporation of amino acids into protein, higher cytochrome oxidase activity, and a higher buoyant density in sucrose density gradients. Mitochondria from the glia-enriched fraction showed relatively high monoamine oxidase and Na(+)- and K(+)-stimulated ATPase activities. The rates of oxidation of various substrates and the acceptor control ratios did not differ appreciably between the two types of mitochondria. The difference in the buoyant density of mitochondria isolated from the neuron-enriched and glia-enriched cell fractions was utilized in attempts to separate neuronal and glial mitochondria from the mixed mitochondria obtained from whole brain homogenates in shallow sucrose gradients. The appearance of two peaks of cytochrome oxidase, monoamine oxidase, and protein concentration in such gradients shows the potential feasibility of such an approach.

The complete genome sequence of a south Indian isolate of Rice tungro spherical virus reveals evidence of genetic recombination between distinct isolates.

Science.gov (United States)

Sailaja, B; Anjum, Najreen; Patil, Yogesh K; Agarwal, Surekha; Malathi, P; Krishnaveni, D; Balachandran, S M; Viraktamath, B C; Mangrauthia, Satendra K

2013-12-01

In this study, complete genome of a south Indian isolate of Rice tungro spherical virus (RTSV) from Andhra Pradesh (AP) was sequenced, and the predicted amino acid sequence was analysed. The RTSV RNA genome consists of 12,171 nt without the poly(A) tail, encoding a putative typical polyprotein of 3,470 amino acids. Furthermore, cleavage sites and sequence motifs of the polyprotein were predicted. Multiple alignment with other RTSV isolates showed a nucleotide sequence identity of 95% to east Indian isolates and 90% to Philippines isolates. A phylogenetic tree based on complete genome sequence showed that Indian isolates clustered together, while Vt6 and PhilA isolates of Philippines formed two separate clusters. Twelve recombination events were detected in RNA genome of RTSV using the Recombination Detection Program version 3. Recombination analysis suggested significant role of 5' end and central region of genome in virus evolution. Further, AP and Odisha isolates appeared as important RTSV isolates involved in diversification of this virus in India through recombination phenomenon. The new addition of complete genome of first south Indian isolate provided an opportunity to establish the molecular evolution of RTSV through recombination analysis and phylogenetic relationship.

Bile Salt and Acid Tolerant of Lactic Acid Bacteria Isolated from Proventriculus of Broiler Chicken

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E. Damayanti

2014-08-01

Full Text Available The aim of this research was to obtain the lactic acid bacteria (LAB as probiotic candidates which have resistance to bile salt and acid condition. LAB was obtained using isolation method from proventriculus of broiler chicken. Selective MRS media with 0.2% CaCO3 addition were used for LAB isolation using pour plate sampling method under anaerobic condition. The result showed that four selected isolates had morphological and biochemical characteristics as LAB. The selected LAB was characterized as follow: antibacterial activities, antibiotic sensitivity, resistance on bile salt, gastric juice and acid condition, and biochemical identification. Antibacterial activities assay of cell free supernatant was confirmed using disc paper diffusion method which was arranged on factorial design and each treatment consisted of three replications. The cell free supernatant of LAB isolates had antibacterial activities against Escherichia coli, Pseudomonas aerugenosa, and Salmonella pullorum. Molecular identification procedure using 16S rRNA sequence analysis showed that R01 and R02 as Pediococcus acidilactici. The viability of the two isolates were tested by acid pH (pH 1, 2, and 3, gastric juice pH 2, and bile salt condition for digestives tract simulation. The result showed that R01 and R02 had a high viability percentages at pH 1, 2, and 3 (95.45%, 99.49%, 104.01%, and 67.17%, 120.74%, 103.4%, respectively and at bile salt simulation for 1-2 hours (100.35%-102.71% and 100.02%-102.65%, respectively, but at gastric juice simulation for 1-2 hours, the P. acidilactici R01 had higher viability than P. acidilactici R02 (59.69%-76.53% versus 43.57%-40.69%, respectively. In the antibiotic sensitivity test for three antibiotics (i.e. erythromicin 15 µg, penicillin G 10 µg, and streptomycin 10 µg, the P. acidilactici R02 showed resistance to Streptomycin and Penicillin. It is concluded that P. acidilactici R01 and P. acidilactici R02 isolated from proventriculus

Short communication: In vitro antimicrobial susceptibility of Mycoplasma bovis isolates identified in milk from dairy cattle in Belgium, Germany, and Italy.

Science.gov (United States)

Barberio, A; Flaminio, B; De Vliegher, S; Supré, K; Kromker, V; Garbarino, C; Arrigoni, N; Zanardi, G; Bertocchi, L; Gobbo, F; Catania, S; Moroni, P

2016-08-01

The objective of this study was to assess the in vitro antimicrobial susceptibility of 73 isolates of Mycoplasma bovis isolated from milk of dairy cattle herds of Belgium, Germany, and Italy. Minimal inhibitory concentration (MIC) values were determined by the microbroth dilution method for the following antimicrobials: erythromycin, spiramycin, tilmicosin, tylosin, lincomycin, enrofloxacin, doxycycline, oxytetracycline, florfenicol, and tiamulin. Macrolides, florfenicol, oxytetracycline, and enrofloxacin, were chosen because they represent antimicrobials families commonly used in several countries for treatment of M. bovis, and their MIC values in cattle population are reported in several studies, allowing a comparison with previous data. Doxycycline and tiamulin were selected to assess the susceptibility of M. bovis to new antimicrobials, because they are not registered in the European Union for the treatment of dairy cattle. Among the agents of the different antimicrobial classes, the macrolides showed the highest concentration to inhibit 90% of isolates (MIC90), all above the highest concentration tested: >8μg/mL for erythromycin, >16μg/mL for spiramycin, and >32μg/mL for tilmicosin and tylosin. Also the MIC90 of lincomycin was above the highest concentration tested (>32μg/mL), but the distribution of the MIC values was almost perfectly bimodal: 41 isolates had a MIC ≤0.5μg/mL and 30 isolates >32μg/mL. Oxytetracycline had a 2-fold higher concentration to inhibit 50% of isolates (2 vs. 0.5μg/mL) and 1-fold higher MIC90 (4 vs. 2μg/mL) than doxycycline. Enrofloxacin and florfenicol had both a MIC90 of 2μg/mL, whereas tiamulin had a MIC90 of 0.5μg/mL. Significant differences on the MIC values were found among the 3 countries for several antimicrobials: compared with Germany, Belgium and Italy showed significantly higher MIC for lincomycin, spiramycin, and tylosin, and lower for oxytetracycline and florfenicol. The Belgian isolates showed the lowest MIC

Seismic isolation systems designed with distinct multiple frequencies

International Nuclear Information System (INIS)

Wu, Ting-shu; Seidensticker, R.W.

1991-01-01

Two systems for seismic base isolation are presented. The main feature of these system is that, instead of only one isolation frequency as in conventional isolation systems, they are designed to have two distinct isolation frequencies. When the responses during an earthquake exceed the design value(s), the system will automatically and passively shift to the secondly isolation frequency. Responses of these two systems to different ground motions including a harmonic motion with frequency same as the primary isolation frequency, show that no excessive amplification will occur. Adoption of these new systems certainly will greatly enhance the safety and reliability of an isolated superstructure against future strong earthquakes. 3 refs

[Isolation and identification of cow-origin Cryptosporidium isolates in Hefei].

Science.gov (United States)

Sun, Tao; Liu, Wei; Wang, Ju-Hua; Xue, Xiu-Heng; Zhao, Chang-Cheng; Li, Pei-Ying

2011-12-01

To isolate cow-origin Cryptosporidium in Hefei, and identify its species. 285 dairy cattle fecal samples collected from a farm in Hefei were examined by using floating saturated solution of sucrose and modified acid-fast staining. Cryptosporidium oocysts were isolated and purified from positive fecal samples. Genetic DNA was extracted to be the template. According to the sequence of 18S rRNA gene and HSP70 gene from Cryptosporidium sp., the primers were designed and synthesized. The PCR products were amplified by PCR and nested-PCR. The nested PCR products were cloned and sequenced. Homology searches and phylogenic tree construction were done by DNAStar software. Five fecal samples were positive by morphological methods with an infection rate of 1.8% (5/285). Oocysts from the 5 positive fecal samples were elliptical or ovoid detected by using floating saturated solution of sucrose and modified acid-fast staining with the size of 7.37 microm x 6.13 microm and 7.58 microm x 6.20 microm, and a shape index of 1.20 and 1.22, respectively. Nested-PCR resulted in a 18S rRNA and HSP70 gene fragments with approximately 250 bp and 325 bp, respectively. The five isolates showed a high level of nucleic acid identity with sequence data of the 18S rRNA gene of Cryptosporidium andersoni (DQ989573), and they were clustered in the same clade. The highest HSP70 gene sequence identity was found among the five isolates and other reported C. andersoni isolates (AY954892 and DQ989576), and they were placed into the same clade. The cow-origin Cryptosporidium isolates derived from Hefei is Cryptosporidium andersoni.

Characterization of lactic acid bacteria isolated from poultry farms in ...

African Journals Online (AJOL)

The Lactobacilli strains, both isolated from faeces, produced higher amounts of cells and lactic acid from soils as compared to the lactococci strain isolated from feathers. L (+)-lactic acid is the only optical isomer for use in pharmaceutical and food industries because is only adapted to assimilate this form. The optical isomers ...

A half mode inkjet printed tunable ferrite isolator

KAUST Repository

Ghaffar, Farhan A.; Vaseem, Mohammed; Bray, Joey. R.; Shamim, Atif

2017-01-01

. The isolation band can be controlled by changing the applied magnetostatic bias. As the bias is varied from 1500 Oe to 3500 Oe the center frequency of the isolation band varies from 4.45 GHz to 9 GHz. The measured response of the isolator shows that it can

Differentiation of enzymatic activity of yeasts and yeast-like microorganisms isolated from various environments

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Elżbieta Bogusławska-Wąs

2014-08-01

Full Text Available The aim of study was to determinate enzymatic activity of yeast-like organisms - Candida lipolytica, Rhodotorula rubra, Trichosporon beigelii, Zygosaccharomyces sp. - isolated from the Szczecin Lagoon and herring salads. We have shown that lipolytic activity was higher than protcolytic for every strain tested. The lowest activity level was found out for amylolytic hydrolases. The results also demonstrated that yeast-like organisms isolated from the Szczecin Lagoon revealed much higher average enzymatic activity compared to tbe same species isolated from herring salads, excepting C. lipolytica.

Compost as a source of microbial isolates for the bioremediation of heavy metals: In vitro selection

Energy Technology Data Exchange (ETDEWEB)

Vargas-Garcia, Maria del Carmen, E-mail: mcvargas@ual.es; Lopez, Maria Jose, E-mail: mllopez@ual.es; Suarez-Estrella, Francisca, E-mail: fsuarez@ual.es; Moreno, Joaquin, E-mail: jcasco@ual.es

2012-08-01

Heavy metal pollution has become a major environmental concern nowadays and the bioremediation of polluted habitats is an increasingly popular strategy due to both its efficiency and safety. A screening and selection protocol based on different composting processes was designed in order to isolate heavy metal-resistant microorganisms. A collection of 51 microorganisms was obtained and most of them showed the capability to tolerate heavy metals in multi-polluted aqueous systems (Cd(II), Cr(VI), Ni, Pb, Zn(II)), as well as to remove them. The highest detoxification ratios were observed for Pb. Some of the isolates detoxifying more than a 90% of this metal, while the other metals were removed in a range between 20% and 60%. The best isolates (Graphium putredinis, Fusarium solani, Fusarium sp. and Penicillium chrysogenum) were further assayed in order to determine the predominant removal mechanism and the potential use of their dead biomass as a biosorbent. Intracellular accumulation was the prevalent mechanism for most isolates and metals, with the exception of Ni. In this case, the proportion removed by extracellular adsorption was similar or even higher than that removed by intracellular accumulation. Thus, the efficiency of living cells was higher than that of dead biomass except in the case of Ni. - Highlights: Black-Right-Pointing-Pointer Composting is a good reservoir for the isolation of HM-resistant microorganisms. Black-Right-Pointing-Pointer Pb was the most removed heavy metal in multi-polluted aqueous systems. Black-Right-Pointing-Pointer Intracellular accumulation was the predominant mechanism for heavy metal removal. Black-Right-Pointing-Pointer Graphium putredinis, which detoxifies organic pollutants, was the most efficient isolate.

Isolation and Identification of L-asparaginase producing Erwinia strains which isolated from Potato Farms

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Arastoo Badoei-Dalfard

2016-09-01

Full Text Available Introduction: L-Asparaginase can be effectively used for the treatment of lymphoblastic leukemia. The rapid growth of cancer cells are needed for L-asparagine abundant storage. L-asparaginase catalyzes the hydrolysis of L-asparagine into L-aspartic acid and ammonia. The purpose of this study was to isolate and identify the L-asparaginase producing Erwinia strains from the potato farms of Jiroft. Materials and methods: Pectolytic Erwinia species isolated from crumbling potato in M9 medium. The desired L-asparaginase producing bacteria were isolated based on the color changes. Biochemical-microbial and the plant pathogenicity tests of these strains were also investigated with potato and geranium. The L-asparaginase production and molecular detection of these Erwinia strains were also investigated. Results: In this study, L-asparaginase producing Erwinia was isolated on the CVP and M9 mediums. The inoculation of Erwinia strains on the potato and geranium plants showed that Er8 and Er11 species have the ability to cause plant pathogenicity. Results showed that the maximum pathogenicity of Er8 and Er11 was observed after 48 and 15 h of inoculation in potato and geranium plants, respectively. 16S rDNA sequencing and phylogenetic analyses exhibited that Er8 and Er11 strains were similar to Erwinia chrysanthemi with 98% homology. Discussion and conclusion: Because of several applications of the Erwinia L-asparaginase in various fields, isolated Erwinia and their L-asparaginase can be suitable for applied utilization.

High prevalence and antimicrobial resistance of urinary tract infection isolates in febrile young children without localizing signs in Taiwan.

Science.gov (United States)

Wu, Chang-Teng; Lee, Hao-Yuan; Chen, Chyi-Liang; Tuan, Pao-Lan; Chiu, Cheng-Hsun

2016-04-01

Antimicrobial susceptibility and prevalence of pediatric urinary tract infection (UTI) is very useful for pediatricians in selecting effective antibiotics in time to improve outcomes in patients. This study aimed to determine the prevalence rate, bacterial distribution, and antimicrobial susceptibility of UTI in febrile young children at a teaching hospital in northern Taiwan. From January 2011 to December 2011, all urinary isolates from suspected cases of UTI in febrile young children aged from 1 day to 36 months visiting the Pediatric Emergency Room of Chang Gung Children's Hospital, Taoyuan, Taiwan were identified by conventional methods. Antibiotic susceptibility was determined according to the Clinical and Laboratory Standards Institute. A total of 5470 (78%) from 7009 eligible children were enrolled in the study, and 619 (11.3%) had a diagnosis of UTI. The most prevalent bacterium was Escherichia coli (68%) followed by Klebsiella pneumoniae (8.1%) and Proteus mirabilis (6.8%). Ampicillin, piperacillin, and trimethoprim-sulfamethoxazole (TMP-SMX) showed a higher resistance rate in the three predominant bacteria. All tested bacteria showed higher resistance to ampicillin (79.3%) and TMP-SMX (44.1%), and lower resistance to cefazolin (17.7%) and gentamicin (13.0%). Fourteen percent of the isolates produced extended spectrum β-lactamase (ESBL), among which 93.33% were E. coli isolates. The overall prevalence of UTI in this study was higher than previously reported in febrile children. Higher antimicrobial resistance was found in ampicillin and TMP-SMX. Among commonly used antibiotics, cefazolin and gentamicin are recommended to treat UTI in febrile children aged < 3 years without localizing signs. Copyright © 2015. Published by Elsevier B.V.

Isolation and antibiogram of Staphylococcus, Streptococcus and Escherichia coli isolates from clinical and subclinical cases of bovine mastitis

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Nihar Nalini Mohanty,

2013-08-01

Full Text Available Aim: The present study was aimed to isolate and evaluate the continuous change in the pattern of drug resistance showed by different mastitogenic organisms, isolated from clinical and subclinical cases of mastitis.Materials and Methods: The study was carried out using 150 milk samples received from various clinical and subclinical cases, from which the causative organisms were isolated and subjected to in vitro antibiotic sensitivity test.Results: The bacteriological analysis of the samples indicated the presence of both Gram positive and Gram negative organisms followed by isolation of isolates like Staphylococcus, E. coli, Streptococcus, Bacillus, Corynebacterium, Listeria, Klebsiella. The in vitro sensitivity of Staphylococcus, E. coli and Streptococcus isolates revealed that they were more sensitive towards newer antimicrobials like Levofloxacin and Enrofloxacin.Conclusion: The prevalence of Staphylococcus was found to be maximum followed by Streptococcus and E. coli among the isolated organisms. Levofloxacin and Enrofloxacin were found to be most effective against the targeted isolates.

Measuring protected-area isolation and correlations of isolation with land-use intensity and protection status.

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Seiferling, Ian S; Proulx, Raphaël; Peres-Neto, Pedro R; Fahrig, Lenore; Messier, Christian

2012-08-01

Protected areas cover over 12% of the terrestrial surface of Earth, and yet many fail to protect species and ecological processes as originally envisioned. Results of recent studies suggest that a critical reason for this failure is an increasing contrast between the protected lands and the surrounding matrix of often highly altered land cover. We measured the isolation of 114 protected areas distributed worldwide by comparing vegetation-cover heterogeneity inside protected areas with heterogeneity outside the protected areas. We quantified heterogeneity as the contagion of greenness on the basis of NDVI (normalized difference vegetation index) values, for which a higher value of contagion indicates less heterogeneous land cover. We then measured isolation as the difference between mean contagion inside the protected area and mean contagion in 3 buffer areas of increasing distance from the protected-area border. The isolation of protected areas was significantly positive in 110 of the 114 areas, indicating that vegetation cover was consistently more heterogeneous 10-20 km outside protected areas than inside their borders. Unlike previous researchers, we found that protected areas in which low levels of human activity are allowed were more isolated than areas in which high levels are allowed. Our method is a novel way to assess the isolation of protected areas in different environmental contexts and regions. ©2011 Society for Conservation Biology.

Biochemical analysis of a papain-like protease isolated from the latex of Asclepias curassavica L.

Science.gov (United States)

Liggieri, Constanza; Obregon, Walter; Trejo, Sebastian; Priolo, Nora

2009-02-01

Most of the species belonging to Asclepiadaceae family usually secrete an endogenous milk-like fluid in a network of laticifer cells in which sub-cellular organelles intensively synthesize proteins and secondary metabolites. A new papain-like endopeptidase (asclepain c-II) has been isolated and characterized from the latex extracted from petioles of Asclepias curassavica L. (Asclepiadaceae). Asclepain c-II was the minor proteolytic component in the latex, but showed higher specific activity than asclepain c-I, the main active fraction previously studied. Both enzymes displayed quite distinct biochemical characteristics, confirming that they are different enzymes. Crude extract was purified by cation exchange chromatography (FPLC). Two active fractions, homogeneous by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and mass spectrometry, were isolated. Asclepain c-II displayed a molecular mass of 23,590 Da, a pI higher than 9.3, maximum proteolytic activity at pH 9.4-10.2, and showed poor thermostability. The activity of asclepain c-II is inhibited by cysteine proteases inhibitors like E-64, but not by any other protease inhibitors such as 1,10-phenantroline, phenylmethanesulfonyl fluoride, and pepstatine. The Nterminal sequence (LPSFVDWRQKGVVFPIRNQGQCGSCWTFSA) showed a high similarity with those of other plant cysteine proteinases. When assayed on N-alpha-CBZ-amino acid-p-nitrophenyl esters, the enzyme exhibited higher preference for the glutamine derivative. Determinations of kinetic parameters were performed with N-alpha-CBZ-L-Gln-p-nitrophenyl ester as substrate: K(m)=0.1634 mM, k(cat)=121.48 s(-1), and k(cat)/K(m)=7.4 x 10(5) s(-1)/mM.

Comparison of Vibrio harveyi strains isolated from shrimp farms and from culture collection in terms of toxicity and antibiotic resistance.

Science.gov (United States)

Nakayama, Tatsuya; Ito, Emi; Nomura, Nakao; Nomura, Nobuhiko; Matsumura, Masatoshi

2006-05-01

Vibrio harveyi strains isolated from shrimp farms (wild strains) were compared with those from culture collections in terms of minimum inhibitory concentration (MIC) and toxicity. Wild strains had higher MIC values for four antibiotics (kanamycin, carbenicillin, oxytetracycline and ampicillin) and also showed higher toxicity compared with culture collection strains. Vibrio harveyi with the lowest antibacterial resistance was chosen to test if a gradual increase in antibiotic concentration and frequent subculture would enhance its antibiotic resistance. Results showed that V. harveyi was able to develop resistance to oxytetracycline. The MIC value was 250 times higher compared with the MIC before subculturing. Moreover, the V. harveyi strain developed slightly higher toxicity. Therefore, it is possible that there is a relationship between antibiotic resistance and toxicity in V. harveyi.

The study of salinity and drought tolerance of Sinorhizobium meliloti isolated from province of Kerman in vivo condition

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mahboobe abolhasani zeraatkar

2009-06-01

Full Text Available It is well known that the host plant inoculation by native strains with high efficiency has a positive effect on plant yield and biological nitrogen fixation process. The main aim of this investigation was to based on salinity and drought experiments, four isolates of Sinorhizobium meliloti (S27K and S36K tolerant isolates, S109K semi-sensitive isolate, S56K sensitive isolate were selected for plant inoculation which was under drought stress in greenhouse condition. This experiment was carried out by using a factorial model in completely randomized design. Results showed that inoculation of alfalfa plants with high salinity and drought tolerant of Sinorhizobium meliloti bacteria could increased biological nitrogen fixation process (symbiotic efficiency, percent crude protein and yield of alfalfa under salinity and drought conditions significantly. There were not any significant differences between S27K and S36K isolates and positive control (no nitrogen limitation. Symbiotic efficiency increased 3.4 times higher than alfalfa plants were inoculated by sensitive isolates S56K when alfalfa plants were inoculated by S27K and S36K isolates.

Plant-Adapted Escherichia coli Show Increased Lettuce Colonizing Ability, Resistance to Oxidative Stress and Chemotactic Response

Science.gov (United States)

Dublan, Maria de los Angeles; Ortiz-Marquez, Juan Cesar Federico; Lett, Lina; Curatti, Leonardo

2014-01-01

Background Escherichia coli is a widespread gut commensal and often a versatile pathogen of public health concern. E. coli are also frequently found in different environments and/or alternative secondary hosts, such as plant tissues. The lifestyle of E. coli in plants is poorly understood and has potential implications for food safety. Methods/Principal Findings This work shows that a human commensal strain of E. coli K12 readily colonizes lettuce seedlings and produces large microcolony-like cell aggregates in leaves, especially in young leaves, in proximity to the vascular tissue. Our observations strongly suggest that those cell aggregates arise from multiplication of single bacterial cells that reach those spots. We showed that E. coli isolated from colonized leaves progressively colonize lettuce seedlings to higher titers, suggesting a fast adaptation process. E. coli cells isolated from leaves presented a dramatic rise in tolerance to oxidative stress and became more chemotactic responsive towards lettuce leaf extracts. Mutant strains impaired in their chemotactic response were less efficient lettuce colonizers than the chemotactic isogenic strain. However, acclimation to oxidative stress and/or minimal medium alone failed to prime E. coli cells for enhanced lettuce colonization efficiency. Conclusion/Significance These findings help to understand the physiological adaptation during the alternative lifestyle of E. coli in/on plant tissues. PMID:25313845

Maltaricin CPN, a new class IIa bacteriocin produced by Carnobacterium maltaromaticum CPN isolated from mould-ripened cheese.

Science.gov (United States)

Hammi, I; Delalande, F; Belkhou, R; Marchioni, E; Cianferani, S; Ennahar, S

2016-11-01

The purpose of this study was to isolate, characterize and determine the structure and the antibacterial activities of a bacteriocin produced by Carnobacterium maltaromaticum CPN, a strain isolated from unpasteurized milk Camembert cheese. This bacteriocin, termed maltaricin CPN, was produced at higher amounts in MRS broth at temperatures between 15°C and 25°C. It was purified to homogeneity from culture supernatant by using a simple method consisting of cation-exchange and reversed-phase chromatographies. Mass spectrometry showed that maltaricin was a 4427·29 Da bacteriocin. Its amino acid sequence was determined by Edman degradation which showed that it had close similarity with bacteriocins of the class IIa. Maltaricin CPN consisted in fact of 44 unmodified amino acids including two cysteine residues at positions 9 and 14 linked by a disulphide bond. The antimicrobial activity of maltaricin CPN covered a range of bacteria, with strong activity against many species of Gram-positive bacteria, especially the food-borne pathogen Listeria monocytogenes, but no activity against Gram-negative ones. In the studied conditions, C. maltaromaticum CPN produced a new class IIa bacteriocin with strong anti-Listeria activity. The study covers the purification and the structural characterization of a new bacteriocin produced by strain C. maltaromaticum CPN isolated from Camembert cheese. Its activity against strains of L. monocytogenes and higher production rates at relatively low temperatures show potential technological applications to improve the safety of refrigerated food. © 2016 The Society for Applied Microbiology.

Effect of nanocellulose isolation techniques on the formation of reinforced poly(vinyl alcohol nanocomposite films

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H. Y. Zhan

2012-10-01

Full Text Available Three techniques including acid hydrolysis (AH, 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO-mediated oxidation (TMO and ultrasonication (US were introduced to isolate nanocellulose from microcrystalline cellulose, in order to reinforce poly(vinyl alcohol (PVA films. Important differences were noticed in fiber quality of nanocellulose and film properties of PVA nanocomposite films. The TMO treatment was more efficient in nanocellulose isolation with higher aspect ratio, surface charge (–47 mV and yields (37%. While AH treatment resulted in higher crystallinity index (88.1% and better size dispersion. The fracture surface, thermal behavior and mechanical properties of the PVA nanocomposite films were investigated by means of scanning electron microscopy (SEM, differential scanning calorimetry (DSC, thermogravimetric analysis (TGA and tensile testing. The results showed that both the TMO-derived and AH-derived nanocellulose could be dispersed homogeneously in the PVA matrices. AH/PVA films had higher elongation at break (51.59% at 6 wt% nanocellulose loading as compared with TMO/PVA, while TMO/PVA films shown superior tensile modulus and strength with increments of 21.5% and 10.2% at 6wt% nanocellulose loading. The thermal behavior of the PVA nanocomposite films was higher improved with TMO-derived nanofibrils addition.

Evaluation of Virulence Factors In vitro, Resistance to Osmotic Stress and Antifungal Susceptibility of Candida tropicalis Isolated from the Coastal Environment of Northeast Brazil

Science.gov (United States)

Zuza-Alves, Diana L.; de Medeiros, Sayama S. T. Q.; de Souza, Luanda B. F. C.; Silva-Rocha, Walicyranison P.; Francisco, Elaine C.; de Araújo, Maria C. B.; Lima-Neto, Reginaldo G.; Neves, Rejane P.; Melo, Analy S. de Azevedo; Chaves, Guilherme M.

2016-01-01

Several studies have been developed regarding human health risks associated with the recreational use of beaches contaminated with domestic sewage. These wastes contain various micro-organisms, including Candida tropicalis. In this context, the objective of this study was to characterize C. tropicalis isolates from the sandy beach of Ponta Negra, Natal, Rio Grande do Norte, Brazil, regarding the expression of in vitro virulence factors, adaptation to osmotic stress and susceptibility to antifungal drugs. We analyzed 62 environmental isolates and observed a great variation among them for the various virulence factors evaluated. In general, environmental isolates were more adherent to human buccal epithelial cells (HBEC) than C. tropicalis ATCC13803 reference strain, and they also showed increased biofilm production. Most of the isolates presented wrinkled phenotypes on Spider medium (34 isolates, 54.8%). The majority of the isolates also showed higher proteinase production than control strains, but low phospholipase activity. In addition, 35 isolates (56.4%) had high hemolytic activity (hemolysis index > 0.55). With regard to C. tropicalis resistance to osmotic stress, 85.4% of the isolates were able to grow in a liquid medium containing 15% sodium chloride. The strains were highly resistant to the azoles tested (fluconazole, voriconazole and itraconazole). Fifteen strains were resistant to the three azoles tested (24.2%). Some strains were also resistant to amphotericin B (14 isolates; 22.6%), while all of them were susceptible for the echinocandins tested, except for a single strain of intermediate susceptibility to micafungin. Our results demonstrate that C. tropicalis isolated from the sand can fully express virulence attributes and showed a high persistence capacity on the coastal environment; in addition of showing high minimal inhibitory concentrations to several antifungal drugs used in current clinical practice, demonstrating that environmental isolates may

Isolation and screening phosphate solubilizers from composts as biofertilizer

International Nuclear Information System (INIS)

Phua Choo Kwai Hoe; Khairuddin Abdul Rahim; Latiffah Norddin; Abdul Razak Ruslan

2006-01-01

Phosphate solubilizers are miroorganisms that able to solubilize insoluble inorganic phosphate compounds or hydrolyze organic phosphate to inorganic P. Therefore make the P to be available for plant and consequently enhance plant growth and yield. Recently, phosphate solubilizing microorganisms has been shown to play an important role in the biofertilizer industry. Fifty-one bacterial were isolated from eleven composts. Most of the phosphate solubilizers were isolated from natural farming composted compost and normal composting compost. This shows that both of these composts are more suitable to use for phosphate solubilizer isolation compare commercial composts. Fourteen of the isolates were found to be phosphate solubilizers. These isolates produced a clear zone on the phosphate agar plates, showing their potential as biofertilizer. AP3 was significantly produced the largest clear zone compared with other isolates. This indicates that isolate AP 3 could be a good phosphate solubilizer. Thus, their effectiveness in the greenhouse and field should be evaluated. (Author)

Isolate resistance of Blastocystis hominis to metronidazole.

Science.gov (United States)

Haresh, K; Suresh, K; Khairul Anus, A; Saminathan, S

1999-04-01

Isolates of Blastocystis hominis from infected immigrant workers from Indonesia, Bangladesh and infected individuals from Singapore and Malaysia were assessed for growth pattern and degree of resistance to different concentrations of metronidazole. Viability of the cells was assessed using eosin-brillian cresyl blue which stained viable cells green and nonviable cells red. The Bangladeshi and Singaporean isolates were nonviable even at the lowest concentration of 0.01 mg/ml, whereas 40% of the initial inoculum of parasites from the Indonesian isolate at day one were still viable in cultures with 1.0 mg/ml metronidazole. The study shows that isolates of B. hominis of different geographical origin have different levels of resistance to metronidazole. The search for more effective drugs to eliminate th parasite appears inevitable, especially since surviving parasites from metronidazole cultures show greater ability to multiply in subcultures than controls.

Porcine Pancreatic Lipase Inhibitory Agent Isolated from Medicinal Herb and Inhibition Kinetics of Extracts from Eleusine indica (L. Gaertner

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Siew Ling Ong

2016-01-01

Full Text Available Eleusine indica (Linnaeus Gaertner is a traditional herb known to be depurative, febrifuge, and diuretic and has been reported with the highest inhibitory activity against porcine pancreatic lipase (PPL among thirty two plants screened in an earlier study. This study aims to isolate and identify the active components that may possess high potential as an antiobesity agent. Of the screened solvent fractions of E. indica, hexane fraction showed the highest inhibitory activity of 27.01±5.68% at 100 μg/mL. Bioactivity-guided isolation afforded three compounds from the hexane fraction of E. indica, namely, β-sitosterol, stigmasterol, and lutein. The structures of these compounds were elucidated using spectral techniques. Lutein showed an outstanding inhibitory activity against PPL (55.98±1.04%, with activity 60% higher than that of the reference drug Orlistat. The other compounds isolated and identified were β-sitosterol (2.99±0.80% and stigmasterol (2.68±0.38%. The enzyme kinetics of E. indica crude methanolic extract on PPL showed mixed inhibition mechanism.

Porcine Pancreatic Lipase Inhibitory Agent Isolated from Medicinal Herb and Inhibition Kinetics of Extracts from Eleusine indica (L.) Gaertner.

Science.gov (United States)

Ong, Siew Ling; Mah, Siau Hui; Lai, How Yee

2016-01-01

Eleusine indica (Linnaeus) Gaertner is a traditional herb known to be depurative, febrifuge, and diuretic and has been reported with the highest inhibitory activity against porcine pancreatic lipase (PPL) among thirty two plants screened in an earlier study. This study aims to isolate and identify the active components that may possess high potential as an antiobesity agent. Of the screened solvent fractions of E. indica , hexane fraction showed the highest inhibitory activity of 27.01 ± 5.68% at 100  μ g/mL. Bioactivity-guided isolation afforded three compounds from the hexane fraction of E. indica , namely,  β -sitosterol, stigmasterol, and lutein. The structures of these compounds were elucidated using spectral techniques. Lutein showed an outstanding inhibitory activity against PPL (55.98 ± 1.04%), with activity 60% higher than that of the reference drug Orlistat. The other compounds isolated and identified were  β -sitosterol (2.99 ± 0.80%) and stigmasterol (2.68 ± 0.38%). The enzyme kinetics of E. indica crude methanolic extract on PPL showed mixed inhibition mechanism.

Frozen cord blood hematopoietic stem cells differentiate into higher numbers of functional natural killer cells in vitro than mobilized hematopoietic stem cells or freshly isolated cord blood hematopoietic stem cells.

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Martha Luevano

Full Text Available Adoptive natural killer (NK cell therapy relies on the acquisition of large numbers of NK cells that are cytotoxic but not exhausted. NK cell differentiation from hematopoietic stem cells (HSC has become an alluring option for NK cell therapy, with umbilical cord blood (UCB and mobilized peripheral blood (PBCD34(+ being the most accessible HSC sources as collection procedures are less invasive. In this study we compared the capacity of frozen or freshly isolated UCB hematopoietic stem cells (CBCD34(+ and frozen PBCD34(+ to generate NK cells in vitro. By modifying a previously published protocol, we showed that frozen CBCD34(+ cultures generated higher NK cell numbers without loss of function compared to fresh CBCD34(+ cultures. NK cells generated from CBCD34(+ and PBCD34(+ expressed low levels of killer-cell immunoglobulin-like receptors but high levels of activating receptors and of the myeloid marker CD33. However, blocking studies showed that CD33 expression did not impact on the functions of the generated cells. CBCD34(+-NK cells exhibited increased capacity to secrete IFN-γ and kill K562 in vitro and in vivo as compared to PBCD34(+-NK cells. Moreover, K562 killing by the generated NK cells could be further enhanced by IL-12 stimulation. Our data indicate that the use of frozen CBCD34(+ for the production of NK cells in vitro results in higher cell numbers than PBCD34(+, without jeopardizing their functionality, rendering them suitable for NK cell immunotherapy. The results presented here provide an optimal strategy to generate NK cells in vitro for immunotherapy that exhibit enhanced effector function when compared to alternate sources of HSC.

Phylogenetic analysis of Newcastle disease viruses isolated from commercial poultry in Mozambique, 2011 to 2016

International Nuclear Information System (INIS)

Mapaco, L.P.; Monjane, I.V.A.; Nhamusso, A.E.; Viljoen, G.J; Dundon, W.G.; Achá, S.J.

2016-01-01

Full text: The complete sequence of the fusion (F) protein gene from eleven Newcastle disease viruses (NDV) isolated from commercial poultry in Mozambique between 2011 and 2016 has been generated. The F gene cleavage site motif for all eleven isolates was 112RRRKRF117 indicating that the viruses are virulent. A phylogenetic analysis using the full F gene sequence revealed that the viruses clustered within genotype VIIh and showed a higher similarity to NDVs from South Africa, China and Southeast Asia than to viruses previously described in Mozambique in 1994 to 1995 and 2005. The characterization of these new NDVs has important implications for Newcastle disease management and control in Mozambique. (author)

Isolation and characterization of lignin from the oak wood bioethanol production residue for adhesives.

Science.gov (United States)

Lee, Soo Jung; Kim, Hyun Joo; Cho, Eun Jin; Song, Younho; Bae, Hyeun-Jong

2015-01-01

Lignin was isolated from the residue of bioethanol production with oak wood via alkaline and catalyzed organosolv treatments at ambient temperature to improve the purity of lignin for the materials application. The isolated lignins were analyzed for their chemical composition by nitrobenzene oxidation method and their functionality was characterized via wet chemistry method, element analysis, (1)H NMR, GPC and FTIR-ATR. The isolated lignin by acid catalyzed organosolv treatment (Acid-OSL) contained a higher lignin content, aromatic proton, phenolic hydroxyl group and a lower nitrogen content that is more reactive towards chemical modification. The lignin-based adhesives were prepared and the bond strength was measured to evaluate the enhanced reactivity of lignin by the isolation. Two steps of phenolation and methylolation were applied for the modification of the isolated lignins and their tensile strengths were evaluated for the use as an adhesive. The acid catalyzed organosolv lignin-based adhesives had comparable bond strength to phenol-formaldehyde adhesives. The analysis of lignin-based adhesives by FTIR-ATR and TGA showed structural similarity to phenol adhesive. The results demonstrate that the reactivity of lignin was enhanced by isolation from hardwood bioethanol production residues at ambient temperature and it could be used in a value-added application to produce lignin-based adhesives. Copyright © 2014 Elsevier B.V. All rights reserved.

Speciation and antifungal susceptibility profiles of Candida isolates from vaginitis patients attending STD Clinic at a Tertiary Care Hospital

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G Sasikala

2018-01-01

Full Text Available Back ground: Candidiasis is the most common vaginal infection affecting approximately 50–72% of women. Rapid identification of yeast isolates to species level is essential to optimize antifungal treatment. Aim: To determine the prevalence of various Candida species among vaginal candidiasis and to determine the antifungal susceptibility pattern of the isolates. Materials and Methods: A total of 471 women who were clinically diagnosed to have vaginal candidiasis were included in the study. Out of 471 vaginitis patients, 91 were positive for Candida species. All the isolates were speciated comprising five species – C. albicans 42 (46.1%, C. krusei 5 (5.5%, C. glabrata 40 (43.9%, C. tropicalis 3 (3.3%, and C. gullermondi 1 (1.1%. Antifungal susceptibility testing result of all Candida isolates are 100% susceptible to amphotericin B, nystatin, flucytosine, econazole, ketoconazole, miconazole, fluconazole. C. krusei isolates are showing 100% resistance to fluconazole. Discussion: In the present study, C. albicans is most common species 46.1% followed by C. glabarata. C. albicans adhere to vaginal, epithelial cells in significantly higher number than other Candida species. This could explain relative higher frequency of C. albicans in vaginal candidiasis. Conclusion: Presumptive identification followed by confirmation of Candida species helps to initiate early appropriate antifungal treatment, thereby reducing the morbidity and mortality.

Isolation of peat swamp forest foliar endophyte fungi as biofertilizer

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Safinah Surya Hakim

2017-01-01

Full Text Available Peatland restoration activity is facing many obstacles, particularly in planting techniques and poor nutrient in peat soil. Naturally, endophytic fungi are abundant and have great potential as biofertilizer. This research investigates the potential endophytic fungi isolated from leaves of peat swamp tree species for biofertilizer. Research activities include: exploration, in vitro test to examine the phosphate solubilization and identification. Result showed that there were 360 leave segments collected from 4 sampling locations. The colonization percentage of 222 isolates ranged from 52.17% - 60.17%. Fifty seven morphospecies were selected from 222 isolates. Twelve isolates demonstrated ability to produce clear zones and ten isolates were selected for identification. It is concluded that twelve isolated demonstrated potential ability to produce clear zone and Penicillum citrinum isolate P3.10 was identified as an isolate that show the highest potential ability as a biofertilizer

Phylogenetic relationships of Chaetomium isolates based on the ...

African Journals Online (AJOL)

Molecular characterization of 18 Chaetomium isolates collected from India based on the internal transcribed spacer (ITS) region of the rRNA gene sequences was done. Phylogenetic analysis of full length ITS region showed that Chaetomium globosum isolates, Cg1, Cg2, Cg6, Cg11 and Cg15, Chaetomium spp. isolates, ...

Isolation and characterization of copper tolerant bacterial isolates

International Nuclear Information System (INIS)

Farooq, S.; Shoeb, E.; Badar, U.; Akhtar, J.

2008-01-01

Twelve bacterial strains were isolated from metal contaminated sites close to the chemical factory, Purification and characterization of these strains was done. Maximum tolerable concentration (MTC) of all the isolated strains was determined against heavy metals cadmium chloride (CdCl/sub 2/), copper sulphate (CuSO/sub 4/), and nickel chloride (NiCI/sub 2/) and antibiotics kanamycin (Km), streptomycin (Sm), and chloramphenicol (Cm). Most promising strain was found to be GESSF012 which showed MTC of 4.5 mM and 1.6 mM against CdCI/sub 2/ in enriched and minimal media respectively; whereas MTC of 750 micro g/ml was against Sm. GESSF012 demonstrated the occurrence of multiple stress tolerance as this strain showed considerable tolerance against other heavy metals including CuSO/sub 4/, (3.0 mM in enriched media and 1.8 mM in minimal media) and NiCl/sub 2/, (2.0 mM in enriched media and 1.8 mM in minimal media) as well as other antibiotics Cm and Km (150 and 125 micro g/ml respectively). Plasmids were detected in most of the strains including GESSF012. (author)

The biofilm-positive Staphylococcus epidermidis isolates in raw materials, foodstuffs and on contact surfaces in processing plants.

Science.gov (United States)

Schlegelová, J; Babák, V; Holasová, M; Dendis, M

2008-01-01

Isolates from the "farm to fork" samples (182 isolates from 2779 samples) were examined genotypically (icaAB genes) and phenotypically (in vitro biofilm formation, typical growth on Congo red agar; CRA) with the aim to assess the risk of penetration of virulent strains of Staphylococcus epidermidis into the food chain. The contamination of meat and milk products was significantly higher in comparison with raw materials. Contamination of contact surfaces in the meat-processing plants was significantly lower than that of contact surfaces in the dairy plants. The ica genes (which precondition the biofilm formation) were concurrently detected in 20 isolates that also showed a typical growth on CRA. Two ica operon-negative isolates produced biofilm in vitro but perhaps by an ica-independent mechanism. The surfaces in the dairy plants and the milk products were more frequently contaminated with ica operon-positive strains (2.3 and 1.2 % samples) than the other sample types (0-0.6 % samples).

Arginase activity of Leishmania isolated from patients with cutaneous leishmaniasis.

Science.gov (United States)

Badirzadeh, A; Taheri, T; Abedi-Astaneh, F; Taslimi, Y; Abdossamadi, Z; Montakhab-Yeganeh, H; Aghashahi, M; Niyyati, M; Rafati, S

2017-09-01

Cutaneous leishmaniasis (CL) is one of the most important vector-borne parasitic diseases, highly endemic in Iran, and its prevalence is increasing all over the country. Arginase (ARG) activity in isolated Leishmania parasites from CL patients is yet to be explored. This study aimed to compare the ARG activity of isolated Leishmania promastigotes from CL patients with a standard strain of Leishmania major and its influences on the disease pathogenesis. We recruited 16 confirmed CL patients from Qom Province, in central Iran; after detection of Leishmania species using PCR-RFLP, we assessed the levels of ARG in the isolated promastigotes and determined the parasites' growth rate. Only L. major was identified from CL patients. The level of ARG activity in the isolated Leishmania promastigotes from CL patients was significantly higher than that obtained from the standard strain of L. major. No significant correlations between ARG activity and lesion size, number or duration were observed; in contrast, a significant negative correlation was seen between ARG level and Leishmania' growth rate. The obtained results suggest that increased ARG expression and activity in the isolated Leishmania promastigotes might contribute to the higher parasite infectivity and play a major role in the pathogenicity of the CL. © 2017 John Wiley & Sons Ltd.

Magnetic Quasi-Phase Matching All-Fiber Isolator

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Chunte A. Lu

2010-01-01

Full Text Available We have experimentally demonstrated an all-fiber optical isolator with 20 dB isolation. The result shows that the quasi-phase matching technique via a meter-long magnet array is highly feasible to generate more than 45 degrees of Faraday rotation in the fibers. The all-fiber isolator can also be temperature tuned to operate between 1048 nm and 1066 nm wavelength.

AMT1;1 transgenic rice plants with enhanced NH4(+) permeability show superior growth and higher yield under optimal and suboptimal NH4(+) conditions.

Science.gov (United States)

Ranathunge, Kosala; El-Kereamy, Ashraf; Gidda, Satinder; Bi, Yong-Mei; Rothstein, Steven J

2014-03-01

The major source of nitrogen for rice (Oryza sativa L.) is ammonium (NH4(+)). The NH4(+) uptake of roots is mainly governed by membrane transporters, with OsAMT1;1 being a prominent member of the OsAMT1 gene family that is known to be involved in NH4(+) transport in rice plants. However, little is known about its involvement in NH4(+) uptake in rice roots and subsequent effects on NH4(+) assimilation. This study shows that OsAMT1;1 is a constitutively expressed, nitrogen-responsive gene, and its protein product is localized in the plasma membrane. Its expression level is under the control of circadian rhythm. Transgenic rice lines (L-2 and L-3) overexpressing the OsAMT1;1 gene had the same root structure as the wild type (WT). However, they had 2-fold greater NH4(+) permeability than the WT, whereas OsAMT1;1 gene expression was 20-fold higher than in the WT. Analogous to the expression, transgenic lines had a higher NH4(+) content in the shoots and roots than the WT. Direct NH4(+) fluxes in the xylem showed that the transgenic lines had significantly greater uptake rates than the WT. Higher NH4(+) contents also promoted higher expression levels of genes in the nitrogen assimilation pathway, resulting in greater nitrogen assimilates, chlorophyll, starch, sugars, and grain yield in transgenic lines than in the WT under suboptimal and optimal nitrogen conditions. OsAMT1;1 also enhanced overall plant growth, especially under suboptimal NH4(+) levels. These results suggest that OsAMT1;1 has the potential for improving nitrogen use efficiency, plant growth, and grain yield under both suboptimal and optimal nitrogen fertilizer conditions.

AMT1;1 transgenic rice plants with enhanced NH4 + permeability show superior growth and higher yield under optimal and suboptimal NH4 + conditions

Science.gov (United States)

Rothstein, Steven J.

2014-01-01

The major source of nitrogen for rice (Oryza sativa L.) is ammonium (NH4 +). The NH4 + uptake of roots is mainly governed by membrane transporters, with OsAMT1;1 being a prominent member of the OsAMT1 gene family that is known to be involved in NH4 + transport in rice plants. However, little is known about its involvement in NH4 + uptake in rice roots and subsequent effects on NH4 + assimilation. This study shows that OsAMT1;1 is a constitutively expressed, nitrogen-responsive gene, and its protein product is localized in the plasma membrane. Its expression level is under the control of circadian rhythm. Transgenic rice lines (L-2 and L-3) overexpressing the OsAMT1;1 gene had the same root structure as the wild type (WT). However, they had 2-fold greater NH4 + permeability than the WT, whereas OsAMT1;1 gene expression was 20-fold higher than in the WT. Analogous to the expression, transgenic lines had a higher NH4 + content in the shoots and roots than the WT. Direct NH4 + fluxes in the xylem showed that the transgenic lines had significantly greater uptake rates than the WT. Higher NH4 + contents also promoted higher expression levels of genes in the nitrogen assimilation pathway, resulting in greater nitrogen assimilates, chlorophyll, starch, sugars, and grain yield in transgenic lines than in the WT under suboptimal and optimal nitrogen conditions. OsAMT1;1 also enhanced overall plant growth, especially under suboptimal NH4 + levels. These results suggest that OsAMT1;1 has the potential for improving nitrogen use efficiency, plant growth, and grain yield under both suboptimal and optimal nitrogen fertilizer conditions. PMID:24420570

Biochemical and physicochemical analysis of fish protein isolate recovered from red snapper (Lutjanus sp.) by-product using isoelectric solubilization/precipitation method

Science.gov (United States)

Pramono, H.; Pujiastuti, D. Y.; Sahidu, A. M.

2018-04-01

The effect of acid- and alkali-process on biochemical and physicochemical characteristics of fish protein isolate from red snapper (Lutjanus sp) by-product was evaluated. Protein recovered by alkali process (16.79%) was higher compared to acid process (13.75%). Reduction of lipid content and total volatile basic nitrogen (TVB-N) exhibited in both treatments indicated both process improved fish protein isolate recovered from red snapper by-product. In addition, the increasing of water holding capacity and oil binding capacity were observed. However, high peroxide value of fish protein isolate was showed in both treatment. This finding indicated that acid and alkali process can be used as a useful method to recover proteins from red snapper by-product. Alkali process gave a protein isolate with better overall quality compared to acid process.

Identification of virulence genes carried by bacteriophages obtained from clinically isolated methicillin-resistant Staphylococcus aureus.

Science.gov (United States)

Karasartova, Djursun; Cavusoglu, Zeynep Burcin; Turegun, Buse; Ozsan, Murat T; Şahin, Fikret

2016-12-01

Bacteriophages play an important role in the pathogenicity of Staphylococcus aureus (S. aureus) either by carrying accessory virulence factors or several superantigens. Despite their importance, there are not many studies showing the actual distribution of the virulence genes carried by the prophages obtained from the clinically isolated Staphylococcus. In this study, we investigated prophages obtained from methicillin-resistant S. aureus (MRSA) strains isolated from hospital- and community-associated (HA-CA) infections for the virulence factors. In the study, 43 phages isolated from 48 MRSA were investigated for carrying toxin genes including the sak, eta, lukF-PV, sea, selp, sek, seg, seq chp, and scn virulence genes using polymerase chain reaction (PCR) and Southern blot. Restriction fragment length polymorphism was used to analyze phage genomes to investigate the relationship between the phage profiles and the toxin genes' presence. MRSA strains isolated from HA infections tended to have higher prophage presence than the MRSA strains obtained from the CA infections (97% and 67%, respectively). The study showed that all the phages with the exception of one phage contained one or more virulence genes in their genomes with different combinations. The most common toxin genes found were sea (83%) followed by sek (77%) and seq (64%). The study indicates that prophages encode a significant proportion of MRSA virulence factors.

Interlaboratory reproducibility of DiversiLab rep-PCR typing and clustering of Acinetobacter baumannii isolates.

Science.gov (United States)

Higgins, Paul G; Hujer, Andrea M; Hujer, Kristine M; Bonomo, Robert A; Seifert, Harald

2012-01-01

We have investigated the reproducibility of DiversiLab rep-PCR fingerprints between two laboratories with the aim of determining if the fingerprints and clustering are laboratory-specific or portable. One-hundred non-duplicate Acinetobacter baumannii isolates were used in this study. DNA isolation and rep-PCR were each performed separately in two laboratories and rep-PCR patterns generated in laboratory A were compared with those from laboratory B. Twelve A. baumannii isolates processed in laboratory A showed ≥98 % pattern similarity with the corresponding 12 isolates tested in laboratory B and were considered identical. Sixty-four isolates showed 95-97.9 % similarity with their corresponding isolates. Twenty-three isolates showed 90-94 % similarity with the corresponding isolates, while one isolate showed only 87.4 % similarity. However, intra-laboratory clustering was conserved: isolates that clustered in laboratory A also clustered in laboratory B. While clustering was conserved and reproducible at two different laboratories, demonstrating the robustness of rep-PCR, interlaboratory comparison of individual isolate fingerprints showed more variability. This comparison allows conclusions regarding clonality to be reached independent of the laboratory where the analysis is performed.

We've Got High Hopes: Using Hope to Improve Higher Education

Science.gov (United States)

Acosta, Alan

2017-01-01

In recent years, higher education's focus has changed from curricula-focused on student learning to curricula-intended to meet performance metrics and secure institutional resources. Shifting attention from students' learning to students' performance has left many students, faculty, and staff within higher education feeling isolated and…

Antagonistic Activity of Trichoderma ISolates against Sclerotium rolfsii : Screening of Efficient Isolates from Morocco Soils for Biological Control

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N. Khattabi

2004-12-01

Full Text Available Seventy Trichoderma spp. isolates collected from different regions of Morocco were tested for their capacity to inhibit in vitro mycelial growth of Sclerotium rolfsii, and for their effect on the viability of S. rolfsii sclerotia in the soil. The Trichoderma spp. isolates inhibited mycelial growth of S. rolfsii to various degrees, with 52% of isolates expressing an average inhibition, varying between 45 and 55%. The effect on the viability of sclerotia in the soil also varied between isolates of Trichoderma, with the majority (84% having a slight effect. A group of twenty isolates identified as Trichoderma harzianum when tested in sterilized soil, significantly reduced sclerotial viability though not in natural soil. Four of these isolates (Nz, Kb2, Kb3 and Kf1 showed good antagonistic activity against S. rolfsii and were also highly competitive in natural soil. These isolates would therefore be candidates for development in biological control program.

Species identification of Streptococcus bovis group isolates causing bacteremia

DEFF Research Database (Denmark)

Agergaard, Charlotte N; Knudsen, Elisa; Dargis, Rimtas

2017-01-01

This study compared two MALDI-TOF MS systems (Biotyper and VITEK MS) on clinical Streptococcus bovis group isolates (n=66). The VITEK MS gave fewer misidentifications and a higher rate of correct identifications than the Biotyper. Only the identification of S. lutetiensis by the VITEK MS was reli......This study compared two MALDI-TOF MS systems (Biotyper and VITEK MS) on clinical Streptococcus bovis group isolates (n=66). The VITEK MS gave fewer misidentifications and a higher rate of correct identifications than the Biotyper. Only the identification of S. lutetiensis by the VITEK MS...

Molecular epidemiology of pneumococcal isolates from children in China

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Li-Hua Kang

2016-04-01

Full Text Available Objectives: To investigate the molecular epidemiology of pneumococcal isolates in Chongqing, China. Methods: In this cross-sectional study, 51 invasive Streptococcus pneumoniae (S. pneumoniae strains were from children with invasive pneumococcal disease (IPD and 32 carriage strains from healthy children from January 2010 to December 2013 at the Children’s Hospital of Chongqing Medical University, Chongqing, China. Multilocus sequence typing was used to identify the sequence types (STs. Capsular serotypes were determined by multiplex polymerase chain reaction. Drug susceptibility and resistance was determined by minimum inhibitory concentrations. Results: In this study, 11 serotypes were identified among the 83 S. pneumoniae clinical isolates tested. Prevalent serotypes were 19A (20.4%, 6A/B (20.4%, 19F (15.7%, 14 (14.5%, and 23F (10.8%. Serotype 19F was the most frequent carriage strain, and serotype 19A was the most frequent invasive strain. The ST983 was the most prevalent ST for carriage strains, and ST320 was the most prevalent ST for invasive strains. For gene analysis, psaA (99.5% and piaA (98.6% were present and much conserved in all pneumococci tested. The cps2A and pcsB genes were more frequent in invasive isolates than carriage strains. Antimicrobial resistance rates of invasive pneumococcal isolates to erythromycin, penicillin, meropenem, cefotaxime, and clindamycin were higher than the carriage isolates from children. Conclusion: Our epidemiological evidence shows that 19A, 6A/B, 19F, 14, and 23F remain the most prevalent serotypes, which can be targeted by PCV13. Genotypes and drug resistance varied between carriage and invasive strains. The PsaA and PiaA may be good protein vaccine candidates.

Isolation of cellulose microfibrils - An enzymatic approach

Directory of Open Access Journals (Sweden)

Sain, M.

2006-11-01

Full Text Available Isolation methods and applications of cellulose microfibrils are expanding rapidly due to environmental benefits and specific strength properties, especially in bio-composite science. In this research, we have success-fully developed and explored a novel bio-pretreatment for wood fibre that can substantially improve the microfibril yield, in comparison to current techniques used to isolate cellulose microfibrils. Microfibrils currently are isolated in the laboratory through a combination of high shear refining and cryocrushing. A high energy requirement of these procedures is hampering momentum in the direction of microfibril isolation on a sufficiently large scale to suit potential applications. Any attempt to loosen up the microfibrils by either complete or partial destruction of the hydrogen bonds before the mechanical process would be a step forward in the quest for economical isolation of cellulose microfibrils. Bleached kraft pulp was treated with OS1, a fungus isolated from Dutch Elm trees infected with Dutch elm disease, under different treatment conditions. The percentage yield of cellulose microfibrils, based on their diameter, showed a significant shift towards a lower diameter range after the high shear refining, compared to the yield of cellulose microfibrils from untreated fibres. The overall yield of cellulose microfibrils from the treated fibres did not show any sizeable decrease.

Identification of Salmonella serovars isolated from live molluscan shellfish and their significance in the marine environment.

Science.gov (United States)

Martinez-Urtaza, Jaime; Saco, Montserrat; Hernandez-Cordova, Gustavo; Lozano, Antonio; Garcia-Martin, Oscar; Espinosa, Joaquin

2003-02-01

A study on the presence of Salmonella spp. in live molluscs was performed, which included a description of the different serovars isolated and their relationship to the marine environment. A total of 2,980 samples of shellfish from Galicia (N.W. Spain) were tested for the presence of Salmonella spp. between September 1998 and August 2001. The overall incidence of Salmonella was 1.8% and showed a slight rise during the 3 years of the study. Mussels and oysters presented a higher incidence than clams and cockles, possibly because of their distinct growing habitat. A seasonal pattern was noted for the isolation of Salmonella spp.: 54% of the isolations were detected from September to November. That nearly 67% of the total Salmonella was isolated from shellfish with fecal coliform levels fecal coliforms do not necessarily indicate the absence of Salmonella. A total of nine serovars were found in the 54 Salmonella isolated. Salmonella Senftenberg was the most frequent (50%), followed by Salmonella Typhimurium (18%) and Salmonella Agona (17%). Salmonella Senftenberg was detected frequently during the year, whereas the remaining serovars were detected only on occasional contamination events.

Antibiotic resistance and biofilm formation of some bacteria isolated from sediment, water and fish farms in Malaysia

Science.gov (United States)

Faja, Orooba Meteab; Usup, Gires; Ahmad, Asmat

2018-04-01

A total of 90 isolates of bacteria were isolated, from sediment (10) samples, water (10) samples and fish (12) samples (Sea bass, Snapper, Grouper and Tilapia). These include 22 isolates of bacteria from sediment, 28 isolates from water and 40 isolates from fish. All the isolates were tested for sensitivity to 13 antibiotics using disc diffusion method. The isolates showed high resistance to some antibiotics based on samples source. Isolates from sediment showed highest resistance toward novobiocin, kanamycin, ampicillin and streptomycin while isolates from water showed highest resistance against vancomycin, penicillin, streptomycin and tetracycline, in contrast, in fish sample showed highest resistance toward vancomycin, ampicillin, streptomycin and tetracycline. Most of the isolates showed biofilm formation ability with different degrees. Out of 22 bacteria isolates from water, two isolates were weak biofilm formers, six isolates moderate biofilm formers and fourteen isolates strong biofilm formers. While, out of 28 bacteria isolates from water one isolate was weak biofilm former, five isolates moderate biofilm formers and 22 strong biofilm formers Fish isolate showed three isolates (8%) moderate biofilm formers and 27 isolates strong biofilm formers. Biofilm formation was one of the factors that lead to antibiotic resistance of the bacterial isolates from these samples.

Isolation & characterization of Brucella melitensis isolated from patients suspected for human brucellosis in India

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Anita Barua

2016-01-01

Interpretation & conclusions: The present study showed an overall isolation rate of 17.64 per cent for B. melitensis. There is a need to establish facilities for isolation and characterization of Brucella species for effective clinical management of the disease among patients as well as surveillance and control of infection in domestic animals. Further studies are needed from different geographical areas of the country with different level of endemicity to plan and execute control strategies against human brucellosis.

Similarities between Salmonella Enteritidis isolated from humans and captive wild animals in South Africa.

Science.gov (United States)

Smith, Anthony M; Ismail, Husna; Henton, Maryke M; Keddy, Karen H

2014-12-15

Salmonella is well recognized as an aetiological agent of gastrointestinal and diarrhoeal disease. Salmonella enterica serotype Enteritidis (Salmonella Enteritidis) is one of the commonest serotypes associated with foodborne illness. In South Africa, we compared Salmonella Enteritidis strains isolated from humans with gastroenteritis and strains isolated from captive wild animals, between June 2011 and July 2012. Bacteria were phenotypically characterized using standard microbiological techniques. Genotypic relatedness of isolates was investigated by pulsed-field gel electrophoresis (PFGE) analysis. a diversity of 27 PFGE patterns amongst 196 human non-invasive isolates was shown; two PFGE patterns predominated and accounted for 74% of all human isolates. Human isolates showed a 12% prevalence rate for nalidixic acid resistance. Animal isolates from 5 different sources were investigated. With the exception of an isolate from a ground hornbill, all animal isolates (jaguar, crocodile, lion and poultry) showed PFGE pattern matches to a human isolate. Animal isolates showed susceptibility to all antimicrobial agents tested, with the exception of nalidixic acid resistance in isolates from the lion and poultry source. Our data showed similarities between Salmonella Enteritidis strains isolated from humans and captive wild animals, suggesting a probable common source for strains from humans and animals.

Characterization of Leishmania isolates from Nepalese patients with visceral leishmaniasis.

Science.gov (United States)

Pandey, Kishor; Yanagi, Testuo; Pandey, Basu Dev; Mallik, Arun Kumar; Sherchand, Jeevan Bahadur; Kanbara, Hiroji

2007-05-01

In Nepal, visceral leishmaniasis (VL) is endemic in 13 districts of the central and eastern regions. A total of 166 bone-marrow aspirates were obtained from patients with suspected VL. Ninety-seven were identified as positive by microscopy, and 29 of those were successfully isolated and cultured. We characterized these isolates by molecular analysis and by their ability to infect mice. PCR-restriction fragment length polymorphism analysis of the mini-exon and the cysteine proteinase b gene showed that all isolates were Leishmania donovani, and the restriction pattern of the Nepalese isolates corresponded to the standard Indian strain of L. donovani but differed from that of the Kenyan strain. The single-strand conformation polymorphism analysis of ribosomal internal transcribed spacer showed no genetic heterogeneity within Nepalese isolates. Intraperitoneal inoculation with the promastigotes of all isolates resulted in amastigote proliferation in the spleen of 20 nude mice, of which ten isolates were highly infective, and ten were moderately infective, including one BALB/c mouse. Of the 20 amastigotes isolated from the spleen of nude mice, only the ten highly infective isolates infected BALB/c mice, of which, two isolates were considered to have low infectivity, three isolates were considered to be moderately infective, and five isolates were considered to be highly infective.

Incremental conditions of isolation as a predictor of suicide in prisoners.

Science.gov (United States)

Roma, Paolo; Pompili, Maurizio; Lester, David; Girardi, Paolo; Ferracuti, Stefano

2013-12-10

In a study of the incidence of suicide in jails and prisons under increasing conditions of deprivation in Italy from 2004 to 2008, imprisonment involving greater levels of isolation was found to be associated with a higher rate of suicide. Greater care should be taken to ensure that prisoners in isolation do not commit suicide by limiting this option when possible or providing mental health services when isolation is necessary. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Improved protocol for isolation of Campylobacter spp. from retail broiler meat and use of pulsed field gel electrophoresis for the typing of isolates.

Science.gov (United States)

Oyarzabal, Omar A; Williams, Aretha; Zhou, Ping; Samadpour, Mansour

2013-10-01

To improve the detection of Campylobacter spp. in retail broiler meat, a reference method (R subsamples) based on the enrichment of 25 g of meat in Bolton broth at 42°C under microaerobiosis was compared with an alternative method (A subsamples) consisting in the rinsing of meat samples for 30s in buffered peptone water with antimicrobials with incubation at 42°C under aerobiosis. One piece of meat (breasts, tenderloins and thighs) was rinse in experiment 1 (A1) and two pieces in experiment 2 (A2). Campylobacter spp. were isolated on agar plates and identified by PCR. Retail samples in Alabama had less prevalence (P ≤ 0.05) than samples in the state of Washington. The percentage of positive was higher (P ≤ 0.05) in A than in R subsamples and rinsing two pieces of meat yielded the highest percentage of positive subsamples. R subsamples showed variations in the prevalence by product. However, A subsamples had similar prevalence of positives among products compare to the result from reference method. More Campylobacter coli isolates were collected in A2 subsamples. Pulse field gel electrophoresis (PFGE) was used as subtyping method to study the genome similarity among the isolates from all methods. A larger diversity of isolates were detected by PFGE in A2 subsamples. Denaturing gradient gel electrophoresis analysis suggested that the initial bacterial populations of the meat samples impact the final bacterial profile after enrichment. Rinsing broiler meats was less time consuming, required less sample preparation and was more sensitive than the reference method for the isolation of naturally occurring Campylobacter spp. This new method could help with epidemiological and intervention studies to control Campylobacter spp. Copyright © 2013 Elsevier B.V. All rights reserved.

Seismic isolation structure for pool-type LMFBR - isolation building with vertically isolated floor for NSSS

International Nuclear Information System (INIS)

Sakurai, A.; Shiojiri, H.; Aoyagi, S.; Matsuda, T.; Fujimoto, S.; Sasaki, Y.; Hirayama, H.

1987-01-01

The NSSS isolation floor vibration characteristics were made clear. Especially, the side support bearing (rubber bearing) is effective for horizontal floor motion restraint and rocking motion control. Seismic isolation effects for responses of the reactor components can be sufficiently expected, using the vertical seismic isolation floor. From the analytical and experimental studies, the following has been concluded: (1) Seismic isolation structure, which is suitable for large pool-type LMFBR, were proposed. (2) Seismic response characteristics of the seismic isolation structure were investigated. It was made clear that the proposed seismic isolation (Combination of the isolated building and the isolated NSSS floor) was effective. (orig./HP)

Challenges in hardening technologies using shallow-trench isolation

International Nuclear Information System (INIS)

Shaneyfelt, M.R.; Dodd, P.E.; Draper, B.L.; Flores, R.S.

1998-02-01

Challenges related to radiation hardening CMOS technologies with shallow-trench isolation are explored. Results show that trench hardening can be more difficult than simply replacing the trench isolation oxide with a hardened field oxide

CHARACTERIZATION OF LACTIC ACID BACTERIA ISOLATED FROM SUMBAWA MARE MILK

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Nengah Sujaya

2008-06-01

Full Text Available A study was carried out to isolate and characterize lactic acid bacteria (LAB from the Sumbawa mares milk The Isolation of LAB was conducted in Man Rogosa Sharpe (MRS agar. The isolates were characterized by standard methods, such as Gram staining, cell morphology study and fermentation activities. The ability of the isolates to inhibit some pathogenic bacteria was studied by dual culture assay. Isolates showing the widest spectrum of inhibiting pathogenic bacteria were further identified using API 50 CHL. The results showed that Sumbawa mare milk was dominated by lactobacilli and weisella/leuconostoc. As many as 26 out 36 isolates belong to homofermentative lactobacilli and another 10 isolates belong to both heterofermentative lactobacilli and weissella or leuconostoc. Twenty four isolates inhibited the growth of Escherichia coli 25922, Shigela flexneri, Salmonella typhimurium, and Staphylococcus aureus 29213. Two promising isolates with the widest spectrum of inhibiting pathogenic bacteria, Lactobacillus sp. SKG34 and Lactobacillus sp. SKG49, were identified respectively as Lactobacillus rhamnosus SKG34 and Lactobacillus ramnosus SKG49. These two isolates were specific strains of the sumbawa mare milk and are very potential to be developed as probiotic for human.

Isolate, functionalize, and release: the ISOFURE platform for the functionalization of nanoparticles

International Nuclear Information System (INIS)

Chirra, Hariharasudhan D.; Spencer, David; Hilt, J. Zach

2012-01-01

Polymer-coated inorganic nanoparticles are widely studied as carrier systems for various biomedical applications. For their translation into clinical applications, it is critical that they remain in a stable, non-agglomerated state and are also produced at a high yield with ease. Herein, we introduce a novel methodology called the isolate-functionalize-release (ISOFURE) strategy to synthesize stable hydrogel-coated nanoparticles in the absence of a stabilizing reagent. As a model platform, we isolated and functionalized gold nanoparticles (GNPs) in a degradable poly(beta amino ester) (PBAE) hydrogel composite. Isolation was done either by adding GNPs to the PBAE hydrogel precursor solution or via in situ precipitation of GNPs inside the pre-synthesized PBAE hydrogel. Atom transfer radical polymerization (ATRP) was used as the model reaction to grow a temperature responsive poly(ethylene glycol) 600 dimethacrylate crosslinked poly(N-isopropyl acrylamide) hydrogel shell over the GNP core. Release of the temperature responsive hydrogel-coated GNPs was done by degrading the PBAE ISOFURE matrix in water. Characterization of the various nanoparticles using UV–Vis spectroscopy confirmed in situ precipitation of GNPs as well as ATRP over the GNPs. Light scattering confirmed the presence of temperature sensitive hydrogel shell over the GNP surface. Aging studies showed that the ISOFURE method based crosslinked hydrogel-coated GNPs showed higher stability and yield than that of the solution-based functionalized GNPs. The use of ISOFURE strategy shows promise as a simple tool for enhanced functionalization and stabilization over various nanocarriers under flexible experimental conditions.

New Data on Vaccine Antigen Deficient Bordetella pertussis Isolates

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Valérie Bouchez

2015-09-01

Full Text Available Evolution of Bordetella pertussis is driven by natural and vaccine pressures. Isolates circulating in regions with high vaccination coverage present multiple allelic and antigenic variations as compared to isolates collected before introduction of vaccination. Furthermore, during the last epidemics reported in regions using pertussis acellular vaccines, isolates deficient for vaccine antigens, such as pertactin (PRN, were reported to reach high proportions of circulating isolates. More sporadic filamentous hemagglutinin (FHA or pertussis toxin (PT deficient isolates were also collected. The whole genome of some recent French isolates, deficient or non-deficient in vaccine antigens, were analyzed. Transcription profiles of the expression of the main virulence factors were also compared. The invasive phenotype in an in vitro human tracheal epithelial (HTE cell model of infection was evaluated. Our genomic analysis focused on SNPs related to virulence genes known to be more likely to present allelic polymorphism. Transcriptomic data indicated that isolates circulating since the introduction of pertussis vaccines present lower transcription levels of the main virulence genes than the isolates of the pre-vaccine era. Furthermore, isolates not producing FHA present significantly higher expression levels of the entire set of genes tested. Finally, we observed that recent isolates are more invasive in HTE cells when compared to the reference strain, but no multiplication occurs within cells.

Phylogenetic Analysis of Apple scar skin viroid Isolates in Korea

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Kang Hee Cho

2015-12-01

Full Text Available To identify genome sequences of Apple scar skin viroid (ASSVd isolates in Korea, the field survey was performed from ‘Hongro’ apple orchards located in eight sites in South Korea (Bongwha, Cheongsong, Dangjin, Gimchoen, Muju, Mungyeong, Suwon, and Yeongwol. ASSVd was detected by RT-PCR and PCR fragments were cloned into cloning vector. Full-length viral genomes of eight ASSVd isolates were sequenced and compared with 21 isolates reported previously from Korea, India, China, Japan and Greece. Eight isolates in this study showed 92.2-99.7% nucleotide sequence identities with those reported previously. Phylogenetic analysis showed that seven isolates reported in this study belong to the same group distinct from other groups.

Detection of meca gene from methicillin resistant staphylococcus aureus isolates of north sumatera

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Septiani Nasution, Gabriella; Suryanto, Dwi; Lia Kusumawati, R.

2018-03-01

Methicillin Resistant Staphylococcus aureus (MRSA) is a major pathogen associated with hospital-acquired infections (nosocomial infections). MRSA is a type of S. aureus resistant to the sub-group of beta-lactam antibiotics such as penicillin, cephalosporin, monobactam, and carbapenem. MRSA is resistant because of genetic changes caused by exposure to irrational antibiotic therapy. This study aimed to detect mecA gene in North Sumatra isolates of MRSA and to determine the pattern of antibiotic resistance in S.aureus isolates classified as MRSA by Vitek 2 Compact in the Central Public Hospital Haji Adam Malik, Medan. Samples were 40 isolates of S. aureus classified as MRSA obtained from clinical microbiology specimens. DNA isolation of the isolates was conducted by a method of freeze-thaw cycling. Amplification of mecA gene was done by PCR technique using specific primer for the gene. PCR products were visualized using mini-gel electrophoresis. The results showed that all MRSA isolates showed to have 533 bp band of mecA. Antibiotics test of Vitek 2 Compact showed that despite all isolates were resistant to beta-lactam antibiotics groups; the isolates showed multidrug resistant to other common antibiotics, such as aminoglycosides, macrolides, and fluoroquinolones. However, they were still sensitive to vancomycin (82.5% isolates), linezolid (97.5% isolates), and tigecycline (100% isolates).

Differences in cell morphometry, cell wall topography and gp70 expression correlate with the virulence of Sporothrix brasiliensis clinical isolates.

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Rafaela A Castro

Full Text Available Sporotrichosis is a chronic infectious disease affecting both humans and animals. For many years, this subcutaneous mycosis had been attributed to a single etiological agent; however, it is now known that this taxon consists of a complex of at least four pathogenic species, including Sporothrix schenckii and Sporothrix brasiliensis. Gp70 was previously shown to be an important antigen and adhesin expressed on the fungal cell surface and may have a key role in immunomodulation and host response. The aim of this work was to study the virulence, morphometry, cell surface topology and gp70 expression of clinical isolates of S. brasiliensis compared with two reference strains of S. schenckii. Several clinical isolates related to severe human cases or associated with the Brazilian zoonotic outbreak of sporotrichosis were genotyped and clustered as S. brasiliensis. Interestingly, in a murine subcutaneous model of sporotrichosis, these isolates showed a higher virulence profile compared with S. schenckii. A single S. brasiliensis isolate from an HIV-positive patient not only showed lower virulence but also presented differences in cell morphometry, cell wall topography and abundant gp70 expression compared with the virulent isolates. In contrast, the highly virulent S. brasiliensis isolates showed reduced levels of cell wall gp70. These observations were confirmed by the topographical location of the gp70 antigen using immunoelectromicroscopy in both species. In addition, the gp70 molecule was sequenced and identified using mass spectrometry, and the sequenced peptides were aligned into predicted proteins using Blastp with the S. schenckii and S. brasiliensis genomes.

Antimicrobial susceptibilities and molecular typing of neisseria gonorrhoeae isolates at a medical centre in Taiwan, 2001-2013 with an emphasis on high rate of azithromycin resistance among the isolates.

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Liu, Yen-Hung; Huang, Yu-Tsung; Liao, Chun-Hsing; Hsueh, Po-Ren

2018-05-01

A high prevalence of gonococcal resistance to various antimicrobials and Neisseria gonorrhoeae isolates exhibiting resistance to extended-spectrum cephalosporins have been reported in the past few decades. A total of 226 N. gonorrhoeae isolates obtained from the National Taiwan University Hospital from 2001 to 2013 were evaluated. The minimum inhibitory concentrations (MICs) of the isolates to antimicrobials were determined by the agar dilution method and interpreted using the 2017 clinical breakpoints or epidemiological cut-off values recommended by the Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST). The genetic relatedness of these isolates was determined by multilocus sequence typing. None of the isolates was resistant to ceftriaxone and cefotaxime, and the resistance rates to cefixime, spectinomycin, cefpodoxime, ciprofloxacin, and penicillin were 0.4%, 0.4%, 13.3%, 91.6%, and 87.6%, respectively. The rate of isolates resistant to azithromycin was 14.6% (EUCAST criteria), which is higher than in previous surveillance studies. A total of 57 sequence types (ST) were identified, and ST1901, ST7365, and ST1927 prevailed. Isolates of ST8143 emerged after 2011. ST1901 isolates had relatively higher MIC values for ceftriaxone and azithromycin than those of the other STs. In conclusion, ceftriaxone remains an effective drug of choice for gonorrhoeal management in Taiwan. High rates of azithromycin resistance among N. gonorrhoeae isolates were found. The circulating ST1901 strains with high MIC values for ceftriaxone and azithromycin and the emerging ST8143 strains were alarming. Copyright © 2018 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Differences in pathogenicity of three animal isolates of Mycobacterium species in a mouse model.

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Haodi Dong

Full Text Available Animal mycobacterioses are among the most important zoonoses worldwide. These are generally caused by either Mycobacterium tuberculosis (MTB, M. bovis (MBO or M. avium (MAV. To test the hypothesis that different species of pathogenic mycobacteria isolated from varied anatomic locations or animal species differ in virulence and pathogenicity, we performed experiments with three mycobacteria strains (NTSE-3(MTB, NTSE-4(MBO and NTSE-5 (MAV obtained from animal species. Spoligotyping analysis was used to confirm both MTB and MBO strains while the MAV strain was confirmed by 16s rDNA sequencing. BALB/c mice were intranasally infected with the three strains at low and high CFU doses to evaluate variations in pathogenicity. Clinical and pathological parameters were assessed. Infected mice were euthanized at 80 days post-inoculation (dpi. Measures of lung and body weights indicated that the MBO infected group had higher mortality, more weight loss, higher bacterial burden and more severe lesions in lungs than the other two groups. Cytokine profiles showed higher levels of TNF-α for MBO versus MTB, while MAV had the highest amounts of IFN-β in vitro and in vivo. In vitro levels of other cytokines such as IL-1β, IL-10, IL-12, IL-17, and IFN-β showed that Th1 cells had the strongest response in MBO infected mice and that Th2 cells were inhibited. We found that the level of virulence among the three isolates decreased in the following order MBO>MTB>MAV.

Isolation and immunomodulatory properties of a flavonoid, casticin from Vitex agnus-castus.

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Mesaik, M Ahmed; Murad, Shahnaz; Khan, Khalid Mohammed; Tareen, Rasool Bakhsh; Ahmed, Aqeel; Choudhary, Muhammad Iqbal

2009-11-01

Casticin (1), a flavonoid isolated from the aerial parts of Vitex agnus-castus, was found to be a potent immunomodulatory and cytotoxic compound. The activity was tested in vitro for chemiluminescence, chemotaxis, T-cell proliferation and cytotoxicity. Casticin (1) exhibited a significant inhibitory effect on monocyte oxidative burst in a dose dependent manner. It was found to have a significant suppressive effect on the chemotaxic action at higher concentrations on fMLP (10(-8) m) stimulated neutrophils. It also showed a potent suppressive effect on PHA stimulated T-cell (PMBC).

Isolation, characterization, and evaluation of wild isolates of Lactobacillus reuteri from pig feces.

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Lee, Deog Yong; Seo, Yeon-Soo; Rayamajhi, Nabin; Kang, Mi Lan; Lee, Su In; Yoo, Han Sang

2009-12-01

Lactic acid bacteria (LAB) are a well-used probiotics for health improvements in both humans and animals. Despite of several benefits, non-host-specific LAB showed poor probiotics effects due to difficulty in colonization and competition with normal flora. Therefore, the feasibility of porcine LAB isolates was evaluated as a probiotics. Ten of 49 Lactobacillus spp. isolates harbored 2 approximately 10 kb plasmid DNA. Seven strains were selected based on the safety test, such as hemolytic activity, ammonia, indole, and phenylalanine production. After safety test, five strains were selected again by several tests, such as epithelial adherence, antimicrobial activity, tolerance against acid, bile, heat, and cold-drying, and production of acid and hydrogen peroxide. Then, enzyme profiles (ZYM test) and antibiotics resistance were analyzed for further characterization. Five Lactobacillus reuteri isolates from pig feces were selected by safety and functional tests. The plasmid DNA which was able to develop vector system was detected in the isolates. Together with these approaches, pig-specific Lactobacillus spp. originated from pigs were selected. These strains may be useful tools to develop oral delivery system.

Longitudinal Relationship Between Loneliness and Social Isolation in Older Adults: Results From the Cardiovascular Health Study.

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Petersen, Johanna; Kaye, Jeffrey; Jacobs, Peter G; Quinones, Ana; Dodge, Hiroko; Arnold, Alice; Thielke, Stephen

2016-08-01

To understand the longitudinal relationship between loneliness and isolation. Participants included 5,870 adults 65 years and older (M = 72.89 ± 5.59 years) from the first 5 years of the Cardiovascular Health Study. Loneliness was assessed using a dichotomized loneliness question. Social isolation was assessed using six items from the Lubben Social Network Scale. Yearly life events were included to assess abrupt social network changes. Mixed effects logistic regression was employed to analyze the relationship between isolation and loneliness. Higher levels of social isolation were associated with higher odds of loneliness, as was an increase (from median) in level of social isolation. Life events such as a friend dying were also associated with increased odds of loneliness. These results suggest that average level of isolation and increases in the level of isolation are closely tied to loneliness, which has implications for future assessment or monitoring of loneliness in older adult populations. © The Author(s) 2015.

Photoproduction of isolated photons, inclusively and with a jet, at HERA

International Nuclear Information System (INIS)

Abramowicz, H.; Abt, I.; Adamczyk, L.

2013-12-01

The photoproduction of isolated photons, both inclusive and together with a jet, has been measured with the ZEUS detector at HERA using an integrated luminosity of 374 pb -1 . Differential cross sections are presented in the isolated-photon transverse-energy and pseudorapidity ranges 6 T γ γ T jet jet 2 2 . Differential cross sections are also presented for inclusive isolated photon production as functions of the transverse energy and pseudorapidity of the photon. Higher-order theoretical calculations are compared to the results.

Microbiological features and clinical impact of the type VI secretion system (T6SS) in Acinetobacter baumannii isolates causing bacteremia.

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Kim, Jungok; Lee, Ji-Young; Lee, Haejeong; Choi, Ji Young; Kim, Dae Hun; Wi, Yu Mi; Peck, Kyong Ran; Ko, Kwan Soo

2017-10-03

We investigated the genetic background and microbiological features of T6SS-positive Acinetobacter baumannii isolates and clinical impact of the T6SS in patients with A. baumannii bacteremia. One hundred and 62 A. baumannii isolates from patients with bacteremia in 2 tertiary-care hospitals in Korea were included in this study. Approximately one-third (51/162, 31.5%) of the A. baumannii clinical isolates possessed the hcp gene, and the hcp-positive isolates were found in several genotypes in multilocus sequence typing. The expression and secretion of Hcp protein varied among the clinical isolates. A. baumannii isolates with detectable Hcp secretion (T6SS+) could better outcompete Escherichia coli compared with T6SS- isolates, including hcp-negative and inactivated hcp-positive isolates. In addition, T6SS+ isolates showed higher biofilm-forming activity and better survival in the presence of normal human serum than the T6SS- isolates. T6SS+ isolates were more frequently detected in patients with catheter-related bloodstream infection, haematopoietic stem cell transplant recipients, and patients receiving immunosuppressive agents. However, T6SS was not a prognostic factor for mortality. Our results suggest that the T6SS of A. baumannii is associated with virulence and contributes to infections in immunocompromised patients and those with implanted medical devices.

Isolation & characterization of Brucella melitensis isolated from patients suspected for human brucellosis in India

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Barua, Anita; Kumar, Ashu; Thavaselvam, Duraipandian; Mangalgi, Smita; Prakash, Archana; Tiwari, Sapana; Arora, Sonia; Sathyaseelan, Kannusamy

2016-01-01

Background & objectives: Brucellosis is endemic in the southern part of India. A combination of biochemical, serological and molecular methods is required for identification and biotyping of Brucella. The present study describes the isolation and biochemical, molecular characterization of Brucella melitensis from patients suspected for human brucellosis. Methods: The blood samples were collected from febrile patients suspected to have brucellosis. A total of 18 isolates were obtained from 102 blood samples subjected to culture. The characterization of these 18 isolates was done by growth on Brucella specific medium, biochemical reactions, CO2 requirement, H2S production, agglutination with A and M mono-specific antiserum, dye sensitivity to basic fuchsin and thionin. Further, molecular characterization of the isolates was done by amplification of B. melitensis species specific IS711 repetitive DNA fragment and 16S (rRNA) sequence analysis. PCR-restriction fragment length polymorphism (RFLP) analysis of omp2 locus and IS711 gene was also done for molecular characterization. Results: All 102 suspected samples were subjected to bacteria isolation and of these, 18 isolates could be recovered on blood culture. The biochemical, PCR and PCR-RFLP and 16s rRNA sequencing revealed that all isolates were of B. melitensis and matched exactly with reference strain B. melitensis 16M. Interpretation & conclusions: The present study showed an overall isolation rate of 17.64 per cent for B. melitensis. There is a need to establish facilities for isolation and characterization of Brucella species for effective clinical management of the disease among patients as well as surveillance and control of infection in domestic animals. Further studies are needed from different geographical areas of the country with different level of endemicity to plan and execute control strategies against human brucellosis. PMID:27488010

Inhibitory and enzyme-kinetic investigation of chelerythrine and lupeol isolated from Zanthoxylum rhoifolium against krait snake venom acetylcholinesterase

Energy Technology Data Exchange (ETDEWEB)

Ahmad, Mustaq, E-mail: mushtaq213@yahoo.com [University of Science and Technology, Bannu, (Pakistan). Department of Biotechnology; Weber, Andrea D.; Zanon, Graciane; Tavares, Luciana de C.; Ilha, Vinicius; Dalcol, Ionara I.; Morel, Ademir F., E-mail: ademirfariasm@gmail.com [Universidade Federal de Santa Maria, RS (Brazil). Dept. de Quimica

2014-01-15

The in vitro activity of chelerythrine and lupeol, two metabolites isolated from Zanthoxylum rhoifolium were studied against the venom of the snake Bungarus sindanus (Elapidae). The venom, which is highly toxic to humans, consists mainly by the enzyme acetylcholinesterase (AChE). Both compounds showed activity against the venom, and the alkaloid chelerythrine presented higher activity than did triterpene lupeol. (author)

Genomic and biological characterization of Newcastle disease viruses isolated from migratory mallards (Anas platyrhynchos).

Science.gov (United States)

Habib, Momena; Yaqub, Tahir; Nazir, Jawad; Shehzad, Wasim; Aziz-Ul-Rahman; Sohail, Tayyebah; Mukhtar, Nadia; Mehboob, Arsalan; Munir, Muhammad; Shabbir, Muhammad Zubair

2018-04-30

Given the global evolutionary dynamics of Newcastle disease viruses (NDVs), it is imperative to continue extensive surveillance, routine monitoring and characterization of isolates originating from natural reservoirs (waterfowls). In this report, we isolated and characterized two virulent NDV strains from clinically healthy mallard (Anas platyrhynchos). Both isolates had a genome of 15,192 nucleotides encoding six genes in an order of 3´-NP-P-M-F-HN-L-5´. The biological characteristics (mean death time: 49.5-50 hr, EID 50 10 8.5  ml -1 ) and presence of a typical cleavage site in the fusion (F) protein (112R-R-Q-K-R↓F117) confirmed the velogenic nature of these isolates. Phylogenetic analysis classified both isolates as members of genotype VII within class-II. Furthermore, based upon the hypervariable region of the F gene (375 nt), isolates showed clustering within sub-genotype VIIi. Similarity index and parallel comparison revealed a higher nucleotide divergence from commonly used vaccine strains; LaSota (21%) and Mukteswar (17%). A comparative residues analysis with representative strains of different genotypes, including vaccine strains, revealed a number of substitutions at important structural and functional domains within the F and hemagglutinin-neuraminidase (HN) proteins. Together, the results highlight consistent evolution among circulating NDVs supporting extensive surveillance of the virus in waterfowl to better elucidate epidemiology, evolutionary relationships and their impacts on commercial and backyard poultry.

Psychopathology of social isolation

OpenAIRE

Baek, Sang-Bin

2014-01-01

The most important defining factor of being human is the use of symbolic language. Language or communication problem occurs during the growth, the child will have a higher risk of social isolation and then the survival will be threatened constantly. Today, adolescents and youths are familiar with computer and smart-phone devices, and communication with others by these devices is easy than face-to-face communication. As adolescents and youths live in the comfortable and familiar cyber-world ra...

Purification and characterization of a thermostable alkaline cellulase produced by Bacillus licheniformis 380 isolated from compost

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ÉVILIN G. DE MARCO

2017-10-01

Full Text Available ABSTRACT During composting processes, the degradation of organic waste is accomplished and driven by a succession of microbial populations exhibiting a broad range of functional competencies. A total of 183 bacteria, isolated from a composting process, were evaluated for cellulase activity at different temperatures (37, 50, 60, and 70°C and pH values. Out of the 22 isolates that showed activity, isolate 380 showed the highest cellulase activity. Its ability to produce cellulase was evaluated in culture medium supplemented with carboxymethyl cellulose, microcrystalline cellulose, wheat straw, and rice husk. The culture medium supplemented with carboxymethyl cellulose induced higher enzyme activity after 6 hours of incubation (0.12 UEA mL-1 min-1. For wheat straw and rice husk, the results were 0.08 UEA mL-1 min-1 for both, while for microcrystalline cellulose, 0.04 UEA mL-1 min-1 were observed. The highest carboxymethyl cellulase activity was observed at 60°C (0.14 UEA mL-1 min-1 for both crude and partially purified enzyme after 30 and 120 min of incubation, respectively. Alkalinization of the medium was observed during cultivation in all substrates. The cellulase had a molecular mass of 20 kDa determined by SDS-Page. Isolate 380 was identified as Bacillus licheniformis. This work provides a basis for further studies on composting optimization.

Susceptibility to antimicrobial agents among bovine mastitis pathogens isolated from North American dairy cattle, 2002-2010.

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Lindeman, Cynthia J; Portis, Ellen; Johansen, Lacie; Mullins, Lisa M; Stoltman, Gillian A

2013-09-01

Approximately 8,000 isolates of Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus uberis, Staphylococcus aureus, and Escherichia coli, isolated by 25 veterinary laboratories across North America between 2002 and 2010, were tested for in vitro susceptibility to beta-lactam, macrolide, and lincosamide drugs. The minimal inhibitory concentrations (MICs) of the beta-lactam drugs remained low against most of the Gram-positive strains tested, and no substantial changes in the MIC distributions were seen over time. Of the beta-lactam antimicrobial agents tested, only ceftiofur showed good in vitro activity against E. coli. The MICs of the macrolides and lincosamides also remained low against Gram-positive mastitis pathogens. While the MIC values given by 50% of isolates (MIC50) for erythromycin and pirlimycin and the streptococci were all low (≤0.5 µg/ml), the MIC values given by 90% of isolates (MIC90) were higher and more variable, but with no apparent increase over time. Staphylococcus aureus showed little change in erythromycin susceptibility over time, but there may be a small, numerical increase in pirlimycin MIC50 and MIC90 values. Overall, the results suggest that mastitis pathogens in the United States and Canada have not shown any substantial changes in the in vitro susceptibility to beta-lactam, macrolide, and lincosamide drugs tested over the 9 years of the study.

Occurrence Of Virulence Factors And Antimicrobial Resistance In Pasteurella Multocida Strains Isolated From Slaughter Cattle In Iran

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Faham eKhamesipour

2014-10-01

Full Text Available A total of 30 Pasteurella multocida strains isolated from 333 pneumonic and apparently health slaughter cattle were examined for capsule biosynthesis genes and 23 virulence associated genes by polymerase chain reaction. The disc diffusion technique was used to determine antimicrobial resistance profiles among the isolates. Of the isolates, 23 belonged to capsular type A, 5 to capsular type D and two isolates were untypeable. The distribution of the capsular types in pneumonic lungs and in apparently health lungs was statistically similar. All virulence genes tested were detected among the isolates derived from pneumonic lungs; whereas isolates derived from apparently health lungs carried 16 of the 23 genes. The frequently detected genes among isolates from pneumonic lungs were exbD, hgbA, hgbB, ompA, ompH, oma87 and sodC; whereas tadD, toxA and pmHAS genes occurred less frequently. Most of the adhesins and superoxide dismutases; and all of the iron acquisition and protectin proteins occurred at significantly (p≤0.05 higher frequencies in isolates from pneumonic lungs. Isolates from apparently healthy lungs didn’t carry the following genes; hsf-1, hsf-2, tadD, toxA, nanB, nanH and pmHAS. One adhesion (hsf-1 and two iron acquisition (exbD and tonB genes occurred at significantly (p≤0.05 higher frequencies among capA isolates. All the P. multocida isolates were susceptible to ciprofloxacin, co-trimoxazole, doxycycline, enrofloxacin, nitrofurantoin and tetracyclines. Different proportions of the isolates were however resistant to ampicillin, amoxicillin, erythromycin, lincomycin, penicillin, rifampin, streptomycin and florfenicol. Our results reveal presence of virulence factors in P. multocida strains isolated from symptomatic and asymptomatic bovids. A higher frequency of the factors among isolates from symptomatic study animals may suggest their role in pathogenesis of P. multocida-associated bovine respiratory disease. The results further

Seismic isolation of Advanced LIGO: Review of strategy, instrumentation and performance

International Nuclear Information System (INIS)

Matichard, F; Mittleman, R; Mason, K; Biscans, S; Barnum, S; Evans, M; Foley, S; Lantz, B; Celerier, C; Clark, D; DeBra, D; Kissel, J; Allwine, E; Abbott, B; Abbott, R; Abbott, S; Coyne, D; McIver, J; Birch, J; DeRosa, R

2015-01-01

The new generation of gravitational waves detectors require unprecedented levels of isolation from seismic noise. This article reviews the seismic isolation strategy and instrumentation developed for the Advanced LIGO observatories. It summarizes over a decade of research on active inertial isolation and shows the performance recently achieved at the Advanced LIGO observatories. The paper emphasizes the scientific and technical challenges of this endeavor and how they have been addressed. An overview of the isolation strategy is given. It combines multiple layers of passive and active inertial isolation to provide suitable rejection of seismic noise at all frequencies. A detailed presentation of the three active platforms that have been developed is given. They are the hydraulic pre-isolator, the single-stage internal isolator and the two-stage internal isolator. The architecture, instrumentation, control scheme and isolation results are presented for each of the three systems. Results show that the seismic isolation sub-system meets Advanced LIGO’s stringent requirements and robustly supports the operation of the two detectors. (paper)

Heterogeneous production of proteases from Brazilian clinical isolates of Pseudomonas aeruginosa.

Science.gov (United States)

Galdino, Anna Clara M; Viganor, Lívia; Ziccardi, Mariangela; Nunes, Ana Paula F; Dos Santos, Kátia R N; Branquinha, Marta H; Santos, André L S

2017-12-01

Pseudomonas aeruginosa is an important human pathogen that causes severe infections in a wide range of immunosuppressed patients. Herein, we evaluated the proteolytic profiles of 96 Brazilian clinical isolates of P. aeruginosa recovered from diverse anatomical sites. Cell-associated and extracellular proteases were evidenced by gelatin-SDS-PAGE and by the cleavage of soluble gelatin. Elastase was measured by using the peptide substrate N-succinyl-Ala-Ala-Ala-p-nitroanilide. The prevalence of elastase genes (lasA and lasB) was evaluated by PCR. Bacterial extracts were initially applied on gelatin-SDS-PAGE and the results revealed four distinct zymographic profiles as follows: profile I (composed by bands of 145, 118 and 50kDa), profile II (118 and 50kDa), profile III (145kDa) and profile IV (118kDa). All the proteolytic enzymes were inhibited by EDTA, identifying them as metalloproteases. The profile I was the most detected in both cellular (79.2%) and extracellular (84.4%) extracts. Overall, gelatinase and elastase activities measured in the spent culture media were significantly higher (around 2-fold) compared to the cellular extracts and the production level varied according to the site of bacterial isolation. For instance, tracheal secretion isolates produced elevated amount of gelatinase and elastase measured in both cellular and extracellular extracts. The prevalence of elastase genes revealed that 100% isolates were lasB-positive and 85.42% lasA-positive. Some positive/negative correlations were showed concerning the production of gelatinase, elastase, isolation site and antimicrobial susceptibility. The protease production was highly heterogeneous in Brazilian clinical isolates of P. aeruginosa, which corroborates the genomic/metabolic versatility of this pathogen. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Isolated Early-type Galaxies in the 2dFGRS

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Fuse, Christopher R.; Lamir, C.

2014-01-01

Isolated galaxies are systems that have experienced limited external perturbations, thus the properties of these galaxies are largely due to internal processes. The features of isolated early-type galaxies (IEGs) provide a baseline from which to compare early-type systems residing in higher-density environments. We use the Two-Degree Field Galaxy Redshift Survey (2dFGRS) and the NASA Extragalactic Database (NED) to identify IEGs in the nearby universe. Search criteria in the 2dFGRS were chosen to insure that the IEGs have remained separated from neighboring galaxies for the majority of their lifetimes. Isolated galaxies are chosen utilizing a minimum projected physical separation of 1 Mpc from any neighboring non-dwarf galaxy brighter than Mb = -16.5 mags. A minimum redshift separation of 350 km/s between a candidate galaxy and a neighboring was imposed to further insure the candidate’s isolation. Early results of the search for isolated early-type galaxies in the southern sky are presented.

Mapping of Geographically Isolated Wetlands of Western Siberia Using High Resolution Space Images

Science.gov (United States)

Dyukarev, E.; Pologova, N.; Dyukarev, A.; Lane, C.; Autrey, B. C.

2014-12-01

Using the remote sensing data for integrated study of natural objects is actual for investigation of difficult to access areas of West Siberia. The research of this study focuses on determining the extent and spectral signatures of isolated wetlands within Ob-Tom Interfluve area using Landsat and Quickbird space images. High-resolution space images were carefully examined and wetlands were manually delineated. Wetlands have clear visible signs at the high resolution space images. 567 wetlands were recognized as isolated wetlands with the area about 10 000 ha (of 2.5% of the study area). Isolated wetlands with area less 2 ha are the most frequent. Half of the total amount of wetlands has area less than 6.4 ha. The largest isolated wetland occupies 797 ha, and only 5% have area more than 50 ha. The Landsat 7 ETM+ data were used for analysis of vegetation structure and spectral characteristics of wetlands. The masked isolated wetlands image was classified into 12 land cover classes using ISODATA unsupervised classification. The attribution of unsupervised classification results allowed us to clearly recognize 7 types of wetlands: tall, low and sparse ryams (Pine-Shrub-Sphagnum community), open wetlands with shrub, moss or sedge cover, and open water objects. Analysis of spectral profiles for all classes has shown that Landsat spectral bands 4 and 5 have higher variability. These bands allow to separate wetland classed definitely. Accuracy assessment of isolated wetland map shows a good agreement with expert field data. The work was supported by grants ISTC № 4079.

Increased thiol levels in antimony-resistant Leishmania infantum isolated from treatment-refractory visceral leishmaniasis in Brazil.

Science.gov (United States)

Magalhães, Lucas S; Bomfim, Lays Gs; Mota, Sthefanne G; Cruz, Geydson S; Corrêa, Cristiane B; Tanajura, Diego M; Lipscomb, Michael W; Borges, Valéria M; Jesus, Amélia R de; Almeida, Roque P de; Moura, Tatiana R de

2018-02-01

BACKGROUND Treatment-refractory visceral leishmaniasis (VL) has become an important problem in many countries. OBJECTIVES We evaluated the antimony-resistance mechanisms of Leishmania infantum isolated from VL patients refractory or responsive to treatment with pentavalent antimony. METHODS Strains isolated from antimony-refractory patients (in vitro antimony-resistant isolates) and antimony-responsive patients (in vitro antimony-sensitive isolates) were examined. Morphological changes were evaluated by transmission electron microscopy after trivalent antimony exposure. P-glycoprotein (P-gp) efflux pump activity was evaluated using the pump-specific inhibitor verapamil hydrochloride, and the role of thiol in trivalent antimony resistance was investigated using the enzymatic inhibitor L-buthionine sulfoximine. FINDINGS Antimony treatment induced fewer alterations in the cellular structure of L. infantum resistant isolates than in that of sensitive isolates. P-gp efflux activity was not involved in antimony resistance in these isolates. Importantly, the resistant isolates contained higher levels of thiol compared to the sensitive isolates, and inhibition of thiol synthesis in the resistant isolates recovered their sensitivity to trivalent antimony treatment, and enhanced the production of reactive oxygen species in promastigotes exposed to the drug. MAIN CONCLUSIONS Our results demonstrate that isolates from patients with antimony-refractory VL exhibited higher thiol levels than antimony-sensitive isolates. This indicates that redox metabolism plays an important role in the antimony-resistance of New World VL isolates.

Viscoelasticity of new generation thermoplastic polyurethane vibration isolators

Science.gov (United States)

Bek, Marko; Betjes, Joris; von Bernstorff, Bernd-Steffen; Emri, Igor

2017-12-01

This paper presents the analysis of pressure dependence of three thermoplastic polyurethane (TPU) materials on vibration isolation. The three TPU Elastollan® materials are 1190A, 1175A, and 1195D. The aim of this investigation was to analyze how much the performance of isolation can be enhanced using patented Dissipative bulk and granular systems technology. The technology uses granular polymeric materials to enhance materials properties (without changing its chemical or molecular composition) by exposing them to "self-pressurization," which shifts material energy absorption maxima toward lower frequencies, to match the excitation frequency of dynamic loading to which a mechanical system is exposed. Relaxation experiments on materials were performed at different isobaric and isothermal states to construct mastercurves, the time-temperature-pressure interrelation was modeled using the Fillers-Moonan-Tschoegl model. Dynamic material functions, related to isolation stiffness and energy absorption, were determined with the Schwarzl approximation. An increase in stiffness and energy absorption at selected hydrostatic pressure, compared to its stiffness and energy absorption at ambient conditions, is represented with κk(p, ω), defining the increase in stiffness and κd(p, ω), defining the increase in energy absorption. The study showed that close to the glassy state, moduli of 1190A and 1195D are about 6-9 times higher compared to 1175A, whereas their properties at ambient conditions are, for all practical purposes, the same. TPU 1190A turns out to be most sensitive to pressure: at 300 MPa its properties are shifted for 5.5 decades, while for 1195D and 1175A this shift is only 3.5 and 1.5 decades, respectively. In conclusion, the stiffness and energy absorption of isolation may be increased with pressure for about 100 times for 1190A and 1195D and for about 10 times for 1175A.

A high-affinity inhibitor of yeast carboxypeptidase Y is encoded by TFS1 and shows homology to a family of lipid binding proteins

DEFF Research Database (Denmark)

Bruun, A W; Svendsen, I; Sørensen, S O

1998-01-01

signals for transport into the endoplasmic reticulum. Surprisingly, Ic is encoded by TFS1, which has previously been isolated as a high-copy suppressor of cdc25-1. CDC25 encodes the putative GTP exchange factor for Ras1p/Ras2p in yeast. In an attempt to rationalize this finding, we looked...... degree of specificity, showing a 200-fold higher Ki toward a carboxypeptidase from Candida albicans which is highly homologous to carboxypeptidase Y. The TFS1 gene product shows extensive similarity to a class of proteins termed "21-23-kDa lipid binding proteins", members of which are found in several...

Evaluation of Drug Resistance Pattern of Escherichia coli Strains Isolated from Fasa Vali-e-Asr Hospital Patients

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Sara Abdollahi Kheirabadi

2013-03-01

Full Text Available Background & Objective: Antibiotic resistance due to the widespread use of antibiotics is one of the major causes of failure in antibiotic treatment. The aim of this study was to investigate the rates of antibiotic resistance among Escherichia coli isolates from Fasa Vali-e-Asr Hospital patients.   Materials & Methods : In total, 234 isolates of Escherichia coli strains, obtained from inpatients and outpatients, were studied. The identity of the isolated strains was confirmed by bacteriologic methods. T he drug sensitivity definition test to 17 antibiotics was done via the disk diffusion antibiogram method. Minimum inhibitory concentration (MIC of the resistant isolates to Ciprofloxacin and Imipenem was measured using the s erial dilution method according to the CLSI standards.   Results : The resistance rates of the isolates to Ciprofloxacin and Imipenem by disk diffusion antibiogram method were 22.65% and 11.11% and by serial dilution method were 19.66 % and 9.4% of all the isolates, respectively.   Conclusion: These results show higher resistance of Escherichia coli to Ciprofloxacin and Imipenem as compared to the results in previous studies. Further investigation will shed light on how to more effectively battle antibiotic resistance of virulent microorganisms.

Identifying Rare Variation in Cases of Schizophrenia in the Isolated Population of the Faroe Islands using Whole-genome Sequencing

DEFF Research Database (Denmark)

Als, Thomas Damm; Lescai, Francesco; Dahl, Hans

to map risk variants involved in complex traits. We aim at utilizing samples of cases and controls of the isolated population of the Faroe Islands to conduct whole-genome-sequence analysis in order to identify rare genetic variants associated with schizophrenia. We will search for rare genetic variants...... of developing SZ. However, these studies are designed to examining only “the common variant” proportion of the genomic landscape of SZ. Due to increased genetic drift during founding and potential bottlenecks, followed by population expansion, isolated populations may be particularly useful in identifying rare...... disease variants, that may appear at higher frequencies and/or within a more clearly distinct haplotype structure compared to outbred populations. Small isolated populations also typically show reduced phenotypic, genetic and environmental heterogeneity, thus making them advantageous in studies aiming...

Selection and characterisation of monepantel resistance in Teladorsagia circumcincta isolates.

Science.gov (United States)

Bartley, D J; Devin, L; Nath, M; Morrison, A A

2015-08-01

Monepantel (MPTL) is one of two new anthelmintic compounds introduced onto the sheep market to control gastro-intestinal nematodes. Resistance to this compound is rare but has been reported. In order to preserve the efficacy of this and other anthelmintics, it is essential to understand both (a) the mechanisms involved in the selection of resistance and (b) how the parasites evolve to deal with these compounds. To address these questions three MPTL-resistant Teladorsagia circumcincta isolates (MTci2-11, MTci5-13 and MTci7-12) have been artificially selected in vivo from phenotypically characterised parent isolates (MTci2, MTci5, MTci7 respectively). The selection process involved collecting and culturing eggs from surviving worms from sheep administered sub-optimal dosages of MPTL (Zolvix®) to provide infective larvae to infect further sheep until resistant isolates were generated (between 9 and 13 rounds of selection). A controlled efficacy test was conducted using the original parental isolates and the newly generated MPTL resistant isolates (n = 5 per group). Selected isolates were assessed both under anthelmintic stress (Zolvix®, 2.5 mg/kg bodyweight; MTci-MPTL) and at rest (untreated, MTci-CON). A number of life-history traits were assessed, namely, worm establishment rates, time to patency, faecal egg output, body length of adults and eggs in utero. The estimated resistance status of the selected isolates was confirmed with 48%, 28% and 9% reductions in worm burden at 7-days post Zolvix® administration for MTci2-11-MPTL, MTci5-13-MPTL and MTci7-12-MPTL, respectively, compared with untreated controls. One of the selected isolates MTci7-12-CON showed significantly greater total worm burden (p = 0.025), greater establishment rate (p = 0.033), decreased time to patency (p = 0.048), higher cumulative egg outputs (p = 0.002) compared with its parental derivative MTci7. The trial results suggest that anthelmintic selection in T

Isolation and Characterization of Gramineae and Fabaceae Soda Lignins.

Science.gov (United States)

Domínguez-Robles, Juan; Sánchez, Rafael; Espinosa, Eduardo; Savy, Davide; Mazzei, Pierluigi; Piccolo, Alessandro; Rodríguez, Alejandro

2017-02-04

Some agricultural residues such as wheat or barley straw, as well as certain fast-growing plants like Leucaena leucocephala and Chamaecytisus proliferus , could be used as raw materials for the paper industry as an alternative to traditional plants (eucalyptus, pine, etc.). In the present study, four types of lignin obtained from the spent liquors produced by the pulping processes using the abovementioned feedstocks were isolated and characterized. Lignin samples were acquired through an acid precipitation from these spent liquors. The characterization of the precipitated lignin samples were performed using a Fourier transform infrared spectroscopy (FT-IR) and both liquid- and solid-state nuclear magnetic resonance spectroscopy (NMR) to analyse the chemical structure, and thermogravimetric analysis (TGA) for determining the thermal properties. Additionally, chemical composition of lignin fractions was also measured. Even though they were of different botanical origin, all the studied samples except for wheat straw lignin had a similar chemical composition and thermal behaviour, and identical chemical structure. Wheat straw lignin showed a greater amount of Klason lignin and lower carbohydrate content. Furthermore, this lignin sample showed a higher thermal stability and significantly different cross-peak patterns in the 2D-NMR experiments. The molecular structures corresponding to p -coumarate (PCA), ferulate (FA) and cinnamyl aldehyde end-groups (J) were only detected in wheat isolated lignin.

Isolation and Characterization of Gramineae and Fabaceae Soda Lignins

Science.gov (United States)

Domínguez-Robles, Juan; Sánchez, Rafael; Espinosa, Eduardo; Savy, Davide; Mazzei, Pierluigi; Piccolo, Alessandro; Rodríguez, Alejandro

2017-01-01

Some agricultural residues such as wheat or barley straw, as well as certain fast-growing plants like Leucaena leucocephala and Chamaecytisus proliferus, could be used as raw materials for the paper industry as an alternative to traditional plants (eucalyptus, pine, etc.). In the present study, four types of lignin obtained from the spent liquors produced by the pulping processes using the abovementioned feedstocks were isolated and characterized. Lignin samples were acquired through an acid precipitation from these spent liquors. The characterization of the precipitated lignin samples were performed using a Fourier transform infrared spectroscopy (FT-IR) and both liquid- and solid-state nuclear magnetic resonance spectroscopy (NMR) to analyse the chemical structure, and thermogravimetric analysis (TGA) for determining the thermal properties. Additionally, chemical composition of lignin fractions was also measured. Even though they were of different botanical origin, all the studied samples except for wheat straw lignin had a similar chemical composition and thermal behaviour, and identical chemical structure. Wheat straw lignin showed a greater amount of Klason lignin and lower carbohydrate content. Furthermore, this lignin sample showed a higher thermal stability and significantly different cross-peak patterns in the 2D-NMR experiments. The molecular structures corresponding to p-coumarate (PCA), ferulate (FA) and cinnamyl aldehyde end-groups (J) were only detected in wheat isolated lignin. PMID:28165411

Isolation and Characterization of Gramineae and Fabaceae Soda Lignins

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Juan Domínguez-Robles

2017-02-01

Full Text Available Some agricultural residues such as wheat or barley straw, as well as certain fast-growing plants like Leucaena leucocephala and Chamaecytisus proliferus, could be used as raw materials for the paper industry as an alternative to traditional plants (eucalyptus, pine, etc.. In the present study, four types of lignin obtained from the spent liquors produced by the pulping processes using the abovementioned feedstocks were isolated and characterized. Lignin samples were acquired through an acid precipitation from these spent liquors. The characterization of the precipitated lignin samples were performed using a Fourier transform infrared spectroscopy (FT-IR and both liquid- and solid-state nuclear magnetic resonance spectroscopy (NMR to analyse the chemical structure, and thermogravimetric analysis (TGA for determining the thermal properties. Additionally, chemical composition of lignin fractions was also measured. Even though they were of different botanical origin, all the studied samples except for wheat straw lignin had a similar chemical composition and thermal behaviour, and identical chemical structure. Wheat straw lignin showed a greater amount of Klason lignin and lower carbohydrate content. Furthermore, this lignin sample showed a higher thermal stability and significantly different cross-peak patterns in the 2D-NMR experiments. The molecular structures corresponding to p-coumarate (PCA, ferulate (FA and cinnamyl aldehyde end-groups (J were only detected in wheat isolated lignin.

Serotypes and typability of Campylobacter jejuni and Campylobacter coli isolated from poultry products

DEFF Research Database (Denmark)

Nielsen, Eva Møller; Nielsen, Niels Ladefoged

1999-01-01

to study the serotype distribution of C. jejuni and C. coli isolated from different food products of poultry origin sampled from retail outlets in Denmark. A total of 156 isolates were serotyped, 85% of these were C. jejuni and 15% were C. coli. The most common C. jejuni serotypes were O:2 (30%), O:1...... nontypable. This rate of nontypable isolates is significantly higher than experienced for isolates from other sources than food products, i.e faecal samples from animals and humans. Subculturing and re-typing of the nontypable isolates improved the typability. After two, five and 10 subcultures 16, six...

Characterization of Bacillus thuringiensis soil isolates from Cuba, with insecticidal activity against mosquitoes

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Aileen González

2011-09-01

Full Text Available Chemical insecticides may be toxic and cause environmental degradation. Consequently, biological control for insects represents an alternative with low ecological impact. In this work, three soil isolates (A21, A51 and C17 from different regions of the Cuban archipelago were identified, characterized and evaluated against Aedes aegypti and Culex quinquefasciatus. The new isolates were compared with reference IPS82 strain and two strains isolated from biolarvicides Bactivec and Bactoculicida, respectively. The differentiation was done by morphological, biochemical, bioassays activity and molecular methods (SDS-PAGE, plasmid profile and random amplified polymorphic analysis. All isolates were identified as Bacillus thuringiensis. The A21, A51 and C17 isolates showed higher larvicide activity than Bactivec’s isolated reference strain, against both A. aegypti and C. quinquefasciatus. A21 isolate had a protein profile similar to IPS82 and Bactivec strain. A51 and C17 isolates produced a characteristic proteins pattern. A21 and A51 isolates had plasmid patterns similar to IPS82 standard strain, while C17 isolate had different both plasmid profile and protein bands. All the studied isolates showed a diverse RAPD patterns and were different from the strains previously used in biological control in Cuba. Rev. Biol. Trop. 59 (3: 1007-1016. Epub 2011 September 01.El uso prolongado de insecticidas ha conducido al desarrollo de resistencia en diferentes especies de mosquitos y al incremento de la degradación del ambiente. El control biológico de insectos ha devenido como una alternativa útil y de bajo impacto ambiental. En nuestro estudio fueron identificados, caracterizados tres aislamientos de suelos procedentes de diferentes regiones del archipiélago cubano y comparados con cepas de referencia: aisladas de los biolarvicidas Bactivec y Bactoculicida, además de IPS82. La diferenciación de los mismos se llevó a cabo mediante métodos morfol

Characterization of antimicrobial resistance in Salmonella enterica strains isolated from Brazilian poultry production.

Science.gov (United States)

Mattiello, Samara P; Drescher, Guilherme; Barth, Valdir C; Ferreira, Carlos A S; Oliveira, Sílvia D

2015-11-01

Antimicrobial resistance profiles and presence of resistance determinants and integrons were evaluated in Salmonella enterica strains from Brazilian poultry. The analysis of 203 isolates showed that those from the poultry environment (88 isolates) were significantly more resistant to antimicrobials than isolates from other sources, particularly those isolated from poultry by-product meal (106 isolates). Thirty-seven isolates were resistant to at least three antimicrobial classes. Class 1 integrons were detected in 26 isolates, and the analysis of the variable region between the 5' conserved segment (CS) and 3' CS of each class 1 integron-positive isolate showed that 13 contained a typical 3' CS and 14 contained an atypical 3' CS. One Salmonella Senftenberg isolate harbored two class 1 integrons, showing both typical and atypical 3' CSs. The highest percentage of resistance was found to sulfonamides, and sul genes were detected in the majority of the resistant isolates. Aminoglycoside resistance was detected in 50 isolates, and aadA and aadB were present in 28 and 32 isolates, respectively. In addition, strA and strB were detected in 78.1 and 65.6% isolates resistant to streptomycin, respectively. Twenty-one isolates presented reduced susceptibility to β-lactams and harbored bla(TEM), bla(CMY), and/or bla(CTX-M). Forty isolates showed reduced susceptibility to tetracycline, and most presented tet genes. These results highlight the importance of the environment as a reservoir of resistant Salmonella, which may enable the persistence of resistance determinants in the poultry production chain, contributing, therefore, to the debate regarding the impacts that antimicrobial use in animal production may exert in human health.

Isolation and Characterization of Thermophilic Bacteria from Jordanian Hot Springs: Bacillus licheniformis and Thermomonas hydrothermalis Isolates as Potential Producers of Thermostable Enzymes.

Science.gov (United States)

Mohammad, Balsam T; Al Daghistani, Hala I; Jaouani, Atef; Abdel-Latif, Saleh; Kennes, Christian

2017-01-01

The aim of this study was the isolation and characterization of thermophilic bacteria from hot springs in Jordan. Ten isolates were characterized by morphological, microscopic, biochemical, molecular, and physiological characteristics. Sequencing of the 16S rDNA of the isolates followed by BLAST search revealed that nine strains could be identified as Bacillus licheniformis and one isolate as Thermomonas hydrothermalis . This is the first report on the isolation of Thermomonas species from Jordanian hot springs. The isolates showed an ability to produce some thermostable enzymes such as amylase, protease, cellulose, gelatins, and lecithin. Moreover, the UPGMA dendrogram of the enzymatic characteristics of the ten isolates was constructed; results indicated a high phenotypic diversity, which encourages future studies to explore further industrial and environmental applications.

Isolation and Characterization of Thermophilic Bacteria from Jordanian Hot Springs: Bacillus licheniformis and Thermomonas hydrothermalis Isolates as Potential Producers of Thermostable Enzymes

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Balsam T. Mohammad

2017-01-01

Full Text Available The aim of this study was the isolation and characterization of thermophilic bacteria from hot springs in Jordan. Ten isolates were characterized by morphological, microscopic, biochemical, molecular, and physiological characteristics. Sequencing of the 16S rDNA of the isolates followed by BLAST search revealed that nine strains could be identified as Bacillus licheniformis and one isolate as Thermomonas hydrothermalis. This is the first report on the isolation of Thermomonas species from Jordanian hot springs. The isolates showed an ability to produce some thermostable enzymes such as amylase, protease, cellulose, gelatins, and lecithin. Moreover, the UPGMA dendrogram of the enzymatic characteristics of the ten isolates was constructed; results indicated a high phenotypic diversity, which encourages future studies to explore further industrial and environmental applications.

Heterogeneity of proteins expressed by Brazilian Sporothrix schenckii isolates.

Science.gov (United States)

Fernandes, Geisa Ferreira; Do Amaral, Cristiane Candida; Sasaki, Alexandre; Godoy, Patrício Martinez; De Camargo, Zoilo Pires

2009-12-01

The profiles of proteins present in the exoantigens of Brazilian Sporothrix schenckii isolates were studied and compared by electrophoresis (SDS-PAGE). Thirteen isolates from five different regions of Brazil (1,000 to 2,000 km apart) and ten from a more limited region (200 to 400 km apart within the state of São Paulo) were cultured in Sabouraud, M199 and minimum (MM) media. Qualitative and quantitative differences in the expression of proteins, which varied according to the medium and the isolate, were observed. Fractions with the same MW but varying in intensity were detected, as well as fractions present in 1 isolate but absent in others. Dendrograms were constructed and isolates grouped based on the fractions obtained, irrespective of the intensity. The results showed that Brazilian S. schenckii isolates express different protein profiles, a feature also present in isolates from a more restricted region. The exoantigens were found to have a maximum of 15 protein fractions, ranging in MW from 19-220 KDaltons depending on the medium used for the cultures. These data show the great heterogeneity of Brazilian S. schenckii protein expression.

Draft genome sequencing of giardia intestinalis assemblage B isolate GS: is human giardiasis caused by two different species?

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Oscar Franzén

2009-08-01

Full Text Available Giardia intestinalis is a major cause of diarrheal disease worldwide and two major Giardia genotypes, assemblages A and B, infect humans. The genome of assemblage A parasite WB was recently sequenced, and the structurally compact 11.7 Mbp genome contains simplified basic cellular machineries and metabolism. We here performed 454 sequencing to 16x coverage of the assemblage B isolate GS, the only Giardia isolate successfully used to experimentally infect animals and humans. The two genomes show 77% nucleotide and 78% amino-acid identity in protein coding regions. Comparative analysis identified 28 unique GS and 3 unique WB protein coding genes, and the variable surface protein (VSP repertoires of the two isolates are completely different. The promoters of several enzymes involved in the synthesis of the cyst-wall lack binding sites for encystation-specific transcription factors in GS. Several synteny-breaks were detected and verified. The tetraploid GS genome shows higher levels of overall allelic sequence polymorphism (0.5 versus <0.01% in WB. The genomic differences between WB and GS may explain some of the observed biological and clinical differences between the two isolates, and it suggests that assemblage A and B Giardia can be two different species.

Primary isolated hepatic tuberculosis

International Nuclear Information System (INIS)

Sheikh, A.S.F.; Qureshi, I.H.; Saba, K.; Bukhari, M.H.

2013-01-01

Isolated hepatic tuberculosis without pulmonary or bowel involvement is a diagnostic challenge and can cause considerable morbidity. A young lady from Lahore presented with fever, pain in right hypochondria, nausea and weight loss. CT scan of abdomen showed multiple small hypodense non-enhancing lesions and a heterogeneous texture of liver. Biopsy confirmed the diagnosis of hepatic tuberculosis. It was concluded a case of isolated hepatic tuberculosis without evidence of other primary sites involvement. It is important to consider tuberculosis in the differential diagnosis when suspecting lymphoproliferative or metastatic diseases in a patient with vague symptoms and abnormal hepatic texture on CT. (author)

Diazotrophic bacteria isolated from wild rice Oryza glumaepatula (Poaceae in the Brazilian Amazon

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Paulo Ivan Fernandes Júnior

2013-06-01

. The growth- promoting ability was confirmed for at least five isolates. For these bacteria, the root and shoot growing results showed higher increases when compared to those observed in plants inoculated with the evaluated reference strains. These results indicate that O. glumaepatula is colonized by a high diverse diazotrophic community in the Brazilian Amazon. Further investigations are now being carried out to determine the taxonomic positions of these isolates and their growth promoting mechanisms.

Diazotrophic bacteria isolated from wild rice Oryza glumaepatula (Poaceae) in the Brazilian Amazon.

Science.gov (United States)

Júnior, Paulo Ivan Fernandes; Pereira, Gilmara Maria Duarte; Perin, Liamara; da Silva, Luana Mesquita; Baraúna, Alexandre Cardoso; Alvess, Francilene Muniz; Passos, Samuel Ribeiro; Zilli, Jerri Edson

2013-06-01

-promoting ability was confirmed for at least five isolates. For these bacteria, the root and shoot growing results showed higher increases when compared to those observed in plants inoculated with the evaluated reference strains. These results indicate that O. glumaepatula is colonized by a high diverse diazotrophic community in the Brazilian Amazon. Further investigations are now being carried out to determine the taxonomic positions of these isolates and their growth promoting mechanisms.

Photoproduction of isolated photons, inclusively and with a jet, at HERA

International Nuclear Information System (INIS)

Abramowicz, H.; Abt, I.; Adamczyk, L.; Adamus, M.; Aggarwal, R.; Antonelli, S.; Arslan, O.; Aushev, V.; Aushev, Y.; Bachynska, O.; Barakbaev, A.N.; Bartosik, N.; Behnke, O.; Behr, J.; Behrens, U.; Bertolin, A.; Bhadra, S.; Bloch, I.; Bokhonov, V.; Boos, E.G.

2014-01-01

The photoproduction of isolated photons, both inclusive and together with a jet, has been measured with the ZEUS detector at HERA using an integrated luminosity of 374 pb −1 . Differential cross sections are presented in the isolated-photon transverse-energy and pseudorapidity ranges 6 T γ γ T jet jet 2 2 . Differential cross sections are also presented for inclusive isolated-photon production as functions of the transverse energy and pseudorapidity of the photon. Higher-order theoretical calculations are compared to the results

Isolation of rat adrenocortical mitochondria

Energy Technology Data Exchange (ETDEWEB)

Solinas, Paola [Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States); Department of Medicine, Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States); Fujioka, Hisashi [Electron Microscopy Facility, Department of Pharmacology, Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States); Tandler, Bernard [Department of Biological Sciences, School of Dental Medicine, Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States); Hoppel, Charles L., E-mail: charles.hoppel@case.edu [Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States); Department of Medicine, Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States)

2012-10-12

Highlights: Black-Right-Pointing-Pointer A method for isolation of adrenocortical mitochondria from the adrenal gland of rats is described. Black-Right-Pointing-Pointer The purified isolated mitochondria show excellent morphological integrity. Black-Right-Pointing-Pointer The properties of oxidative phosphorylation are excellent. Black-Right-Pointing-Pointer The method increases the opportunity of direct analysis of adrenal mitochondria from small animals. -- Abstract: This report describes a relatively simple and reliable method for isolating adrenocortical mitochondria from rats in good, reasonably pure yield. These organelles, which heretofore have been unobtainable in isolated form from small laboratory animals, are now readily accessible. A high degree of mitochondrial purity is shown by the electron micrographs, as well as the structural integrity of each mitochondrion. That these organelles have retained their functional integrity is shown by their high respiratory control ratios. In general, the biochemical performance of these adrenal cortical mitochondria closely mirrors that of typical hepatic or cardiac mitochondria.

Antimicrobial susceptibilities and random amplified polymorphic DNA-PCR fingerprint characterization of Lactococcus lactis ssp. lactis and Lactococcus garvieae isolated from bovine intramammary infections.

Science.gov (United States)

Plumed-Ferrer, C; Barberio, A; Franklin-Guild, R; Werner, B; McDonough, P; Bennett, J; Gioia, G; Rota, N; Welcome, F; Nydam, D V; Moroni, P

2015-09-01

In total, 181 streptococci-like bacteria isolated from intramammary infections (IMI) were submitted by a veterinary clinic to Quality Milk Production Services (QMPS, Cornell University, Ithaca, NY). The isolates were characterized by sequence analysis, and 46 Lactococcus lactis ssp. lactis and 47 Lactococcus garvieae were tested for susceptibility to 17 antibiotics. No resistant strains were found for β-lactam antibiotics widely used in clinical practice (penicillin, ampicillin, and amoxicillin), and all minimum inhibitory concentrations (MIC) were far from the resistance breakpoints. Eight strains had MIC intermediate to cefazolin. The random amplification of polymorphic DNA (RAPD)-PCR fingerprint patterns showed a slightly higher heterogeneity for Lc. lactis ssp. lactis isolates than for Lc. garvieae isolates. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Specific Gene Loci of Clinical Pseudomonas putida Isolates.

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Lázaro Molina

Full Text Available Pseudomonas putida are ubiquitous inhabitants of soils and clinical isolates of this species have been seldom described. Clinical isolates show significant variability in their ability to cause damage to hosts because some of them are able to modulate the host's immune response. In the current study, comparisons between the genomes of different clinical and environmental strains of P. putida were done to identify genetic clusters shared by clinical isolates that are not present in environmental isolates. We show that in clinical strains specific genes are mostly present on transposons, and that this set of genes exhibit high identity with genes found in pathogens and opportunistic pathogens. The set of genes prevalent in P. putida clinical isolates, and absent in environmental isolates, are related with survival under oxidative stress conditions, resistance against biocides, amino acid metabolism and toxin/antitoxin (TA systems. This set of functions have influence in colonization and survival within human tissues, since they avoid host immune response or enhance stress resistance. An in depth bioinformatic analysis was also carried out to identify genetic clusters that are exclusive to each of the clinical isolates and that correlate with phenotypical differences between them, a secretion system type III-like was found in one of these clinical strains, a determinant of pathogenicity in Gram-negative bacteria.

High Proportions of Multidrug-Resistant Acinetobacter spp. Isolates in a District in Western India: A Four-Year Antibiotic Susceptibility Study of Clinical Isolates

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Ingvild Odsbu

2018-01-01

Full Text Available The purpose of the study was to determine the proportions of multidrug-resistant (MDR Acinetobacter spp. isolates from the district of Nashik in Western India during the period from 2011–2014. Antibacterial susceptibility testing of isolates from inpatients and outpatients was performed using Kirby–Bauer disc diffusion method to determine inhibitory zone diameters. Proportions of non-susceptible isolates were calculated from the antibacterial susceptibility data. MDR was defined as an isolate being non-susceptible to at least one antibacterial agent in at least three antibacterial categories. The change in proportions of MDR isolates; extended-spectrum β-lactamase (ESBL-producing isolates; and non-susceptible isolates to specific antibacterial categories over calendar time was investigated by logistic regression. The proportions of MDR and ESBL-producing isolates ranged from 89.4% to 95.9% and from 87.9% to 94.0%; respectively. The proportions of non-susceptible isolates to aminoglycosides; carbapenems; antipseudomonal penicillins/β-lactamase inhibitors; cephalosporins; folate pathway inhibitors; or penicillins/β-lactamase inhibitors exceeded 77.5%. Proportions of fluoroquinolone and tetracycline non-susceptible isolates ranged from 65.3% to 83.3% and from 71.3% to 75.9%; respectively. No changes in trends were observed over time; except for a decreasing trend in fluoroquinolone non-susceptible isolates (OR = 0.75 (95% CI, 0.62–0.91. Significantly higher proportions of non-susceptible; MDR and ESBL-producing isolates were found among isolates from the respiratory system compared to isolates from all other specimen types (p < 0.05. High proportions of MDR Acinetobacter spp. isolates were observed in the period from 2011–2014. Antimicrobial stewardship programmes are needed to prevent the emergence and spread of antibiotic resistance.

Teaching basic lung isolation skills on human anatomy simulator: attainment and retention of lung isolation skills.

Science.gov (United States)

Latif, Rana K; VanHorne, Edgar M; Kandadai, Sunitha Kanchi; Bautista, Alexander F; Neamtu, Aurel; Wadhwa, Anupama; Carter, Mary B; Ziegler, Craig H; Memon, Mohammed Faisal; Akça, Ozan

2016-01-20

Lung isolation skills, such as correct insertion of double lumen endobronchial tube and bronchial blocker, are essential in anesthesia training; however, how to teach novices these skills is underexplored. Our aims were to determine (1) if novices can be trained to a basic proficiency level of lung isolation skills, (2) whether video-didactic and simulation-based trainings are comparable in teaching lung isolation basic skills, and (3) whether novice learners' lung isolation skills decay over time without practice. First, five board certified anesthesiologist with experience of more than 100 successful lung isolations were tested on Human Airway Anatomy Simulator (HAAS) to establish Expert proficiency skill level. Thirty senior medical students, who were naive to bronchoscopy and lung isolation techniques (Novice) were randomized to video-didactic and simulation-based trainings to learn lung isolation skills. Before and after training, Novices' performances were scored for correct placement using pass/fail scoring and a 5-point Global Rating Scale (GRS); and time of insertion was recorded. Fourteen novices were retested 2 months later to assess skill decay. Experts' and novices' double lumen endobronchial tube and bronchial blocker passing rates showed similar success rates after training (P >0.99). There were no differences between the video-didactic and simulation-based methods. Novices' time of insertion decayed within 2 months without practice. Novices could be trained to basic skill proficiency level of lung isolation. Video-didactic and simulation-based methods we utilized were found equally successful in training novices for lung isolation skills. Acquired skills partially decayed without practice.

Sloshing of coolant in a seismically isolated reactor

International Nuclear Information System (INIS)

Wu, T.S.; Guildys, J.; Seidensticker, R.W.

1988-01-01

During a seismic event, the liquid coolant inside the reactor vessel has sloshing motion which is a low-frequency phenomenon. In a reactor system incorporated with seismic isolation, the isolation frequency usually is also very low. There is concern on the potential amplification of sloshing motion of the liquid coolant. This study investigates the effects of seismic isolation on the sloshing of liquid coolant inside the reactor vessel of a liquid metal cooled reactor. Based on a synthetic ground motion whose response spectra envelop those specified by the NRC Regulator Guide 1.60, it is found that the maximum sloshing wave height increases from 18 in. to almost 30 in. when the system is seismically isolated. Since higher sloshing wave may introduce severe impact forces and thermal shocks to the reactor closure and other components within the reactor vessel, adequate design considerations should be made either to suppress the wave height or to reduce the effects caused by high waves

Screening and characterization of bacteriocins produced by some Strains of Lactobacillus spp isolated from Iranian Dairy products

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S Mirdamadi

2011-11-01

Full Text Available In this study, the inhibitory effects of bacteriocins of lactobacilli which were isolated from Iranian traditional dairy products was determined against known gram positive, gram negative and yeast by well diffusion technique. Among 8 isolates with higher capability of bacteriocin production, 2 isolates were selected for further investigations. The bacteriocins were purified by iso-propanol and ammonium sulfate precipitation following by dialysis and chromatography technique. The molecular weight of bacteriocins was determined as 45 to 66/2 KDa. by SDS-page electrophoresis. According to the results, the produced bacteriocins had more inhibition effect on Micrococcus luteus PTCC1169, Staphylococcus epidermidis PTCC1435 as well as Bacillus cereus PTCC1247 and with lesser degree of extent on Listeria monocytogenes PTCC 1301. Results also revealed that, Micrococcus luteus  was the most sensitive bacterium among indicator bacteria, while Candid albicans PTCC 5027 identified as the most resistance organism. This research showed that, bacteriocins produced by lactobacilli isolated from traditional dairy products have high potency to be used against microbial pathogens and could be applied as bio-preservative in food products.

Development of Probiotic Milk Drinks Using Probiotic Strain Isolated From Local Yogurt

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Md. Ahmadul Islam

2018-08-01

Full Text Available Obtained result suggested that, Isolate 1 and Isolate 2 during storage at 5±1oC for 15days ranged between 8.75 – 9.55 log cfu/ml those were higher than 5 log cfu/ml. That means isolated lactic acid bacteria (LAB contain probiotic characteristics & among three samples, the probiotic milk drink that was mixed with 10% mango juice was the most acceptable. [Fundam Appl Agric 2018; 3(2.000: 446-452

Partial Sequencing of 16S rRNA Gene of Selected Staphylococcus aureus Isolates and its Antibiotic Resistance

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Harsi Dewantari Kusumaningrum

2016-08-01

Full Text Available The choice of primer used in 16S rRNA sequencing for identification of Staphylococcus species found in food is important. This study aimed to characterize Staphylococcus aureus isolates by partial sequencing based on 16S rRNA gene employing primers 16sF, 63F or 1387R. The isolates were isolated from milk, egg dishes and chicken dishes and selected based on the presence of sea gene that responsible for formation of enterotoxin-A. Antibiotic susceptibility of the isolates towards six antibiotics was also tested. The use of 16sF resulted generally in higher identity percentage and query coverage compared to the sequencing by 63F or 1387R. BLAST results of all isolates, sequenced by 16sF, showed 99% homology to complete genome of four S. aureus strains, with different characteristics on enterotoxin production and antibiotic resistance. Considering that all isolates were carrying sea gene, indicated by the occurence of 120 bp amplicon after PCR amplification using primer SEA1/SEA2,  the isolates were most in agreeing to S. aureus subsp. aureus ST288. This study indicated that 4 out of 8 selected isolates were resistant towards streptomycin. The 16S rRNA gene sequencing using 16sF is useful for identification of S. aureus. However, additional analysis such as PCR employing specific gene target, should give a valuable supplementary information, when specific characteristic is expected.

Full-length genome sequence analysis of four subgroup J avian leukosis virus strains isolated from chickens with clinical hemangioma.

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Lin, Lulu; Wang, Peikun; Yang, Yongli; Li, Haijuan; Huang, Teng; Wei, Ping

2017-12-01

Since 2014, cases of hemangioma associated with avian leukosis virus subgroup J (ALV-J) have been emerging in commercial chickens in Guangxi. In this study, four strains of the subgroup J avian leukosis virus (ALV-J), named GX14HG01, GX14HG04, GX14LT07, and GX14ZS14, were isolated from chickens with clinical hemangioma in 2014 by DF-1 cell culture and then identified with ELISA detection of ALV group specific antigen p27, the detection of subtype specific PCR and indirect immunofluorescence assay (IFA) with ALV-J specific monoclonal antibody. The complete genomes of the isolates were sequenced and it was found that the gag and pol were relatively conservative, while env was variable especially the gp85 gene. Homology analysis of the env gene sequences showed that the env gene of all the four isolates had higher similarities with the hemangioma (HE)-type reference strains than that of the myeloid leukosis (ML)-type strains, and moreover, the HE-type strains' specific deletion of 205-bp sequence covering the rTM and DR1 in 3'UTR fragment was also found in the four isolates. Further analysis on the sequences of subunits of env gene revealed an interesting finding: the gp85 of isolates GX14ZS14 and GX14HG04 had a higher similarity with HPRS-103 and much lower similarity with the HE-type reference strains resulting in GX14ZS14, GX14HG04, and HPRS-103 being clustered in the same branch, while gp37 had higher similarities with the HE-type reference strains when compared to that of HPRS-103, resulted in GX14ZS14, GX14HG04, and HE-type reference strains being clustered in the same branch. The results suggested that isolates GX14ZS14 and GX14HG04 may be the recombinant strains of the foreign strain HPRS-103 with the local epidemic HE-type strains of ALV-J.

Characterization of Candida spp. isolated from vaginal fluid: identification, antifungal susceptibility, and virulence profile - doi: 10.4025/actascihealthsci.v35i1.13557

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Terezinha Inez Estivalet Svidzinski

2013-03-01

Full Text Available A total of 101 (20.0% yeast samples were isolated from vaginal fluids of 504 non-hospitalized patients in Maringá, Paraná State, Brazil and Candida albicans was more frequent specie (93.1% identified by seminested PCR method. All the isolates were susceptible to amphotericin B and nystatin, and 93.1% of them were susceptible to fluconazole. The acid proteinase, hemolytic and phospholipase activities were observed in 99.0, 90.0, and 88.0% of Candida spp., respectively. Around 67.0% of the strains had adherence indexes of 0.5 to 1.5 yeasts by Vero cell, and most of them showed a hydrophilic profile. Correlation studies indicated hydrophilic yeasts presented higher adherence index, proteinase, and phospholipase activities; and a positive correlation between all enzymes was also observed. In addition, the isolates with high hemolytic activity were less susceptible to fluconazole and amphotericin B. These results of Candida prevalence and antifungal susceptibility corroborate with literature’s datas and correlation between virulence factors and MIC values suggest Candida isolates from vaginal fluid less susceptible to antifungal and with higher extracellular enzymes production can be more virulent to cause tissue damage.  

Characterization of Malaysian Trichoderma isolates using random amplified microsatellites (RAMS).

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Siddiquee, Shafiquzzaman; Tan, Soon Guan; Yusuf, Umi Kalsom; Fatihah, Nur Hasan Nudin; Hasan, Md Mainul

2012-01-01

Trichoderma species are commercially applied as biocontrol agents against numerous plant pathogenic fungi due to their production of antifungal metabolites, competition for nutrients and space, and mycoparasitism. However, currently the identification of Trichoderma species from throughout the world based on micro-morphological descriptions is tedious and prone to error. The correct identification of Trichoderma species is important as several traits are species-specific. The Random Amplified Microsatellites (RAMS) analysis done using five primers in this study showed different degrees of the genetic similarity among 42 isolates of this genus. The genetic similarity values were found to be in the range of 12.50-85.11% based on a total of 76 bands scored in the Trichoderma isolates. Of these 76 bands, 96.05% were polymorphic, 3.95% were monomorphic and 16% were exclusive bands. Two bands (250 bp and 200 bp) produced by primer LR-5 and one band (250 bp) by primer P1A were present in all the Trichoderma isolates collected from healthy and infected oil palm plantation soils. Cluster analysis based on UPGMA of the RAMS marker data showed that T. harzianum, T. virens and T. longibrachiatum isolates were grouped into different clades and lineages. In this study we found that although T. aureoviride isolates were morphologically different when compared to T. harzianum isolates, the UPGMA cluster analysis showed that the majority isolates of T. aureoviride (seven from nine) were closely related to the isolates of T. harzianum.

Ecophysiological characterization of Aspergillus carbonarius, Aspergillus tubingensis and Aspergillus niger isolated from grapes in Spanish vineyards.

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García-Cela, E; Crespo-Sempere, A; Ramos, A J; Sanchis, V; Marin, S

2014-03-03

The aim of this study was to evaluate the diversity of black aspergilli isolated from berries from different agroclimatic regions of Spain. Growth characterization (in terms of temperature and water activity requirements) of Aspergillus carbonarius, Aspergillus tubingensis and Aspergillus niger was carried out on synthetic grape medium. A. tubingensis and A. niger showed higher maximum temperatures for growth (>45 °C versus 40-42 °C), and lower minimum aw requirements (0.83 aw versus 0.87 aw) than A. carbonarius. No differences in growth boundaries due to their geographical origin were found within A. niger aggregate isolates. Conversely, A. carbonarius isolates from the hotter and drier region grew and produced OTA at lower aw than other isolates. However, little genetic diversity in A. carbonarius was observed for the microsatellites tested and the same sequence of β-tubulin gene was observed; therefore intraspecific variability did not correlate with the geographical origin of the isolates or with their ability to produce OTA. Climatic change prediction points to drier and hotter climatic scenarios where A. tubingensis and A. niger could be even more prevalent over A. carbonarius, since they are better adapted to extreme high temperature and drier conditions. Copyright © 2013 Elsevier B.V. All rights reserved.

Classification of a moderately oxygen-tolerant isolate from baby faeces as Bifidobacterium thermophilum

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Fliss Ismaïl

2007-08-01

Full Text Available Abstract Background Bifidobacteria are found at varying prevalence in human microbiota and seem to play an important role in the human gastrointestinal tract (GIT. Bifidobacteria are highly adapted to the human GIT which is reflected in the genome sequence of a Bifidobacterim longum isolate. The competitiveness against other bacteria is not fully understood yet but may be related to the production of antimicrobial compounds such as bacteriocins. In a previous study, 34 Bifidobacterium isolates have been isolated from baby faeces among which six showed proteinaceous antilisterial activity against Listeria monocytogenes. In this study, one of these isolates, RBL67, was further identified and characterized. Results Bifidobacterium isolate RBL67 was classified and characterized using a polyphasic approach. RBL67 was classified as Bifidobacterium thermophilum based on phenotypic and DNA-DNA hybridization characteristics, although 16S rDNA analyses and partial groEL sequences showed higher homology with B. thermacidophilum subsp. porcinum and B. thermacidophilum subsp. thermacidophilum, respectively. RBL67 was moderately oxygen-tolerant and was able to grow at pH 4 and at a temperature of 47°C. Conclusion In order to assign RBL67 to a species, a polyphasic approach was used. This resulted in the classification of RBL67 as a Bifidobacterium thermophilum strain. To our knowledge, this is the first report about B. thermophilum isolated from baby faeces since the B. thermophilum strains were related to ruminants and swine faeces before. B. thermophilum was previously only isolated from animal sources and was therefore suggested to be used as differential species between animal and human contamination. Our findings may disapprove this suggestion and further studies are now conducted to determine whether B. thermophilum is distributed broader in human faeces. Furthermore, the postulated differentiation between human and animal strains by growth above 45�

Molecular epidemiology of Corynebacterium pseudotuberculosis isolated from horses in California.

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Haas, Dionei J; Dorneles, Elaine M S; Spier, Sharon J; Carroll, Scott P; Edman, Judy; Azevedo, Vasco A; Heinemann, Marcos B; Lage, Andrey P

2017-04-01

Corynebacterium pseudotuberculosis biovar Equi is an important pathogen of horses. It is increasing in frequency in the United States, and is responsible for various clinical forms of infection, including external abscesses, internal abscesses of the abdominal or thoracic cavities, and ulcerative lymphangitis. The host/pathogen factors dictating the form or severity of infection are currently unknown. Our recent investigations have shown that genotyping C. pseudotuberculosis isolates using enterobacterial repetitive intergenic consensus (ERIC)-PCR is useful for understanding the evolutionary genetics of the species as well for molecular epidemiology studies. The aims of the present study were to assess (i) the genetic diversity of C. pseudotuberculosis strains isolated from horses in California, United States and (ii) the epidemiologic relationships among isolates. One hundred and seven C. pseudotuberculosis biovar Equi isolates from ninety-five horses, and two C. pseudotuberculosis biovar Ovis strains, C. pseudotuberculosis ATCC 19410 T type strain and C. pseudotuberculosis 1002 vaccine strain, were fingerprinted using the ERIC 1+2-PCR. C. pseudotuberculosis isolated from horses showed a high genetic diversity, clustering in twenty-seven genotypes with a diversity index of 0.91. Minimal spanning tree showed four major clonal complexes with a pattern of temporal clustering. Strains isolated from the same horse showed identical ERIC 1+2-PCR genotype, with the exception of two strains isolated from the same animal that showed distinct genotypes, suggesting a co-infection. We found no strong genetic signals related to clinical form (including internal versus external infections). However, temporal clustering of genotypes was observed. Copyright © 2016. Published by Elsevier B.V.

Chemical Compositions and Macrophage Activation of Polysaccharides from Leon's Mane Culinary-Medicinal Mushroom Hericium erinaceus (Higher Basidiomycetes) in Different Maturation Stages.

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Li, Qiao-Zhen; Wu, Di; Chen, Xia; Zhou, Shuai; Liu, Yanfang; Yang, Yan; Cui, Fengjie

2015-01-01

We studied the effect of the maturation stage on the chemical compositions and macrophage activation activity of polysaccharides from the culinary-medicinal mushroom Hericium erinaceus. Results showed that total polysaccharides increased, whereas protein content decreased with the maturation stage development of fruiting body. Nine polysaccharide fractions, 3 from each of the maturity stages IV (small fungal spine stage), V (mid-fungal spine stage) and VI (mature), were prepared using the gradient ethanol precipitation method. The polysaccharide fraction HP4A isolated from the maturating-stage (stage IV) fruiting body had a significant difference from the fractions HP5A (stage V) and HP6A (stage VI) in the molecular weight distribution and monosaccharide compositions. Immunostimulating tests revealed that the polysaccharide fraction HP6 isolated from the mature stage (stage VI) fruiting body presented higher macrophage activation activity. Our findings provided important information for the harvest and use of H. erinaceus with higher qualities and functional benefits.

Enzymatic activity of fungi isolated from crops

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Wioletta A. Żukiewicz-Sobczak

2016-12-01

Full Text Available Aim: To detect and assess the activity of extracellular hydrolytic enzymes and to find differences in enzymograms between fungi isolated from wheat and rye samples and grown on Czapek-Dox Broth and Sabouraud Dextrose Broth enriched with cereal (wheat or rye. Isolated strains were also classified in the scale of biosafety levels (BSL. Material and methods: The study used 23 strains of fungi cultured from samples of wheat and rye (grain, grain dust obtained during threshing and soil collected in the Lublin region (eastern Poland. API ZYM test (bioMérieux was carried out according to the manufacturer’s instructions. Classification of BSL (Biosafety levels was based on the current literature. Results : High enzymatic activity was found in strains cultured in media containing 1% of wheat grain ( Bipolaris holmi, Penicillium decumbens and with an addition of 1% of rye grain ( Cladosporium herbarum, Aspergillus versicolor, Alternaria alternata . The total number of enzymes varied depending on the type of media, and in most cases it was higher in the culture where an addition of cereal grains was used. Conclusions : Isolated strains of fungi reveal differences in the profiles of the enzyme assay. It can be assumed that the substrate enriched in grains stimulate the higher activity of mold enzymes. Key words: enzymatic activity, mold fungi, zymogram, biohazards.

The genotypic characterization of Cronobacter spp. isolated in China.

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Jinghua Cui

Full Text Available Cronobacter spp. (Enterobacter sakazakii is an important pathogen contaminating powdered infant formula (PIF. To describe the genotypic diversity of Cronobacter isolated in China, we identified the isolates using fusA allele sequencing, and subtyped all of the isolates using pulsed-field gel electrophoresis (PFGE, multi-locus sequence typing (MLST, and multiple-locus variable-number tandem-repeat analysis (MLVA. A total of 105 isolates were identified, which included C. sakazakii (58 isolates, C. malonaticus (30 isolates, C. dublinensis (11 isolates, C. turicensis (5 isolates, and C. muytjensii (1 isolate. These isolates were showed to have 85 PFGE-patterns, 71 sequence types (STs, and 55 MLVA-patterns. Comparisons among the three molecular subtyping methods revealed that the PFGE method was the most distinguishable tool in identifying clusters of Cronobacter spp. through DNA fingerprinting, and MLST method came second. However, ESTR-1, ESTR-2, ESTR-3, and ESTR-4 were not effective loci for subtyping Cronobacter spp. such that the MLVA method requires further improvement.

Screening Brazilian Macrophomina phaseolina isolates for alkaline lipases and other extracellular hydrolases.

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Schinke, Claudia; Germani, José C

2012-03-01

Macrophomina phaseolina, phylum Ascomycota, is a phytopathogenic fungus distributed worldwide in hot dry areas. There are few studies on its secreted lipases and none on its colony radial growth rate, an indicator of fungal ability to use nutrients for growth, on media other than potato-dextrose agar. In this study, 13 M. phaseolina isolates collected in different Brazilian regions were screened for fast-growth and the production of hydrolases of industrial interest, especially alkaline lipases. Hydrolase detection and growth rate determination were done on citric pectin, gelatin, casein, soluble starch, and olive oil as substrates. Ten isolates were found to be active on all substrates tested. The most commonly detected enzymes were pectinases, amylases, and lipases. The growth rate on pectin was significantly higher (P media identified CMM 2105, CMM 1091, and PEL as the fastest-growing isolates. The lipase activity of four isolates grown on olive oil was followed for 4 days by measuring the activity in the cultivation broth. The specific lipolytic activity of isolate PEL was significantly higher at 96 h (130 mU mg protein(-1)). The broth was active at 37 °C, pH 8, indicating the potential utility of the lipases of this isolate in mild alkaline detergents. There was a strong and positive correlation (0.86) between radial growth rate and specific lipolytic activity.

Salmonella strains isolated from Galápagos iguanas show spatial structuring of serovar and genomic diversity.

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Lankau, Emily W; Cruz Bedon, Lenin; Mackie, Roderick I

2012-01-01

It is thought that dispersal limitation primarily structures host-associated bacterial populations because host distributions inherently limit transmission opportunities. However, enteric bacteria may disperse great distances during food-borne outbreaks. It is unclear if such rapid long-distance dispersal events happen regularly in natural systems or if these events represent an anthropogenic exception. We characterized Salmonella enterica isolates from the feces of free-living Galápagos land and marine iguanas from five sites on four islands using serotyping and genomic fingerprinting. Each site hosted unique and nearly exclusive serovar assemblages. Genomic fingerprint analysis offered a more complex model of S. enterica biogeography, with evidence of both unique strain pools and of spatial population structuring along a geographic gradient. These findings suggest that even relatively generalist enteric bacteria may be strongly dispersal limited in a natural system with strong barriers, such as oceanic divides. Yet, these differing results seen on two typing methods also suggests that genomic variation is less dispersal limited, allowing for different ecological processes to shape biogeographical patterns of the core and flexible portions of this bacterial species' genome.

Structural markers of the evolution of whey protein isolate powder during aging and effects on foaming properties.

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Norwood, E-A; Le Floch-Fouéré, C; Briard-Bion, V; Schuck, P; Croguennec, T; Jeantet, R

2016-07-01

The market for dairy powders, including high added-value products (e.g., infant formulas, protein isolates) has increased continuously over the past decade. However, the processing and storage of whey protein isolate (WPI) powders can result in changes in their structural and functional properties. It is therefore of great importance to understand the mechanisms and to identify the structural markers involved in the aging of WPI powders to control their end use properties. This study was performed to determine the effects of different storage conditions on protein lactosylations, protein denaturation in WPI, and in parallel on their foaming and interfacial properties. Six storage conditions involving different temperatures (θ) and water activities (aw) were studied for periods of up to 12mo. The results showed that for θ≤20°C, foaming properties of powders did not significantly differ from nonaged whey protein isolates (reference), regardless of the aw. On the other hand, powders presented significant levels of denaturation/aggregation and protein modification involving first protein lactosylation and then degradation of Maillard reaction products, resulting in a higher browning index compared with the reference, starting from the early stage of storage at 60°C. These changes resulted in a higher foam density and a slightly better foam stability (whisking) at 6mo. At 40°C, powders showed transitional evolution. The findings of this study will make it possible to define maximum storage durations and to recommend optimal storage conditions in accordance with WPI powder end-use properties. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A half mode inkjet printed tunable ferrite isolator

KAUST Repository

Ghaffar, Farhan A.

2017-10-24

A novel half mode waveguide based ferrite isolator design is presented in this work. For the first time, tunability of the isolation band is demonstrated for a ferrite isolator. Instead of using the conventional antisymmetric bias the isolator requires a single direction of the magnetic bias field due to the half mode operation. Yttrium Iron Garnet (YIG) is used as the substrate for the device. The metallic walls of the waveguide are realized using inkjet printing. The magnetic biasing applied to the waveguide causes the RF waves to experience negative permeability in one direction of propagation hence providing isolation for this direction. For an applied bias of 3000 Oe, the device provides a maximum isolation figure of merit of 76.7 dB at 7.5 GHz. The isolation band can be controlled by changing the applied magnetostatic bias. As the bias is varied from 1500 Oe to 3500 Oe the center frequency of the isolation band varies from 4.45 GHz to 9 GHz. The measured response of the isolator shows that it can be integrated in any RF system requiring lower cost and good isolation.

Experimental Inoculation of BFDV-Positive Budgerigars (Melopsittacus undulatus with Two Mycobacterium avium subsp. avium Isolates

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Aleksandra Ledwoń

2014-01-01

Full Text Available Beak and feather disease virus- (BFDV- positive (naturally infected but clinically healthy budgerigars (Melopsittacus undulatus were inoculated with two isolates of Mycobacterium avium subsp. avium isolated from naturally infected golden pheasant (Chrysolophus pictus and peafowl (Pavo cristatus. During a period of more than two months after inoculation, samples of cloacal and crop swabs, faeces, and blood were obtained for BFDV and Mycobacterium avium testing with PCR. Birds were euthanized nine weeks after inoculation. All infected budgerigars developed signs typical of mycobacteriosis, but more advanced clinical and pathological changes were visible in the group infected with the pheasant isolate. Only a few cloacal and crop swab samples were positive for Mycobacterium avium subsp. avium despite advanced pathological changes in the internal organs. In the groups infected with mycobacterium isolates the frequency of BFDV-positive samples was higher than in the control group. In the infected groups the frequency of BFDV was substantially higher in the cloacal swabs of birds inoculated with the pheasant isolate than in the peafowl-isolate-infected group.

Experimental inoculation of BFDV-positive budgerigars (Melopsittacus undulatus) with two Mycobacterium avium subsp. avium isolates.

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Ledwoń, Aleksandra; Sapierzyński, Rafał; Augustynowicz-Kopeć, Ewa; Szeleszczuk, Piotr; Kozak, Marcin

2014-01-01

Beak and feather disease virus- (BFDV-) positive (naturally infected) but clinically healthy budgerigars (Melopsittacus undulatus) were inoculated with two isolates of Mycobacterium avium subsp. avium isolated from naturally infected golden pheasant (Chrysolophus pictus) and peafowl (Pavo cristatus). During a period of more than two months after inoculation, samples of cloacal and crop swabs, faeces, and blood were obtained for BFDV and Mycobacterium avium testing with PCR. Birds were euthanized nine weeks after inoculation. All infected budgerigars developed signs typical of mycobacteriosis, but more advanced clinical and pathological changes were visible in the group infected with the pheasant isolate. Only a few cloacal and crop swab samples were positive for Mycobacterium avium subsp. avium despite advanced pathological changes in the internal organs. In the groups infected with mycobacterium isolates the frequency of BFDV-positive samples was higher than in the control group. In the infected groups the frequency of BFDV was substantially higher in the cloacal swabs of birds inoculated with the pheasant isolate than in the peafowl-isolate-infected group.

Proteome Analysis of the Plant Pathogenic Fungus Monilinia laxa Showing Host Specificity

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Olja Bregar

2012-01-01

Full Text Available Brown rot fungus Monilinia laxa (Aderh. & Ruhl. Honey is an important plant pathogen in stone and pome fruits in Europe. We applied a proteomic approach in a study of M. laxa isolates obtained from apples and apricots in order to show the host specifity of the isolates and to analyse differentially expressed proteins in terms of host specifity, fungal pathogenicity and identification of candidate proteins for diagnostic marker development. Extracted mycelium proteins were separated by 2-D electrophoresis (2-DE and visualized by Coomassie staining in a non-linear pH range of 3–11 and Mr of 14–116 kDa. We set up a 2-DE reference map of M. laxa, resolving up to 800 protein spots, and used it for image analysis. The average technical coefficient of variance (13 % demonstrated a high reproducibility of protein extraction and 2-D polyacrylamide gel electrophoresis (2-DE PAGE, and the average biological coefficient of variance (23 % enabled differential proteomic analysis of the isolates. Multivariate statistical analysis (principal component analysis discriminated isolates from two different hosts, providing new data that support the existence of a M. laxa specialized form f. sp. mali, which infects only apples. A total of 50 differentially expressed proteins were further analyzed by LC-MS/MS, yielding 41 positive identifications. The identified mycelial proteins were functionally classified into 6 groups: amino acid and protein metabolism, energy production, carbohydrate metabolism, stress response, fatty acid metabolism and other proteins. Some proteins expressed only in apple isolates have been described as virulence factors in other fungi. The acetolactate synthase was almost 11-fold more abundant in apple-specific isolates than in apricot isolates and it might be implicated in M. laxa host specificity. Ten proteins identified only in apple isolates are potential candidates for the development of M. laxa host-specific diagnostic markers.

Comparative analysis on antibiotic resistance characteristics of Listeria spp. and Enterococcus spp. isolated from laying hens and eggs in conventional and organic keeping systems in Bavaria, Germany.

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Schwaiger, K; Schmied, E-M V; Bauer, J

2010-05-01

By investigating the prevalence and antimicrobial resistance characteristics of Gram-positive bacteria from organic and conventional keeping systems of laying hens, it was to be determined to what extent these properties are influenced by the different systems. For this purpose, a total of 799 cloacal swabs and 800 egg samples were examined. Prevalences for all selected bacteria from cloacal swabs were much the same for both organic and caged birds: Listeria spp.1.3%[org] versus 1.6%[con]; Enterococcus spp. 95.5%[org] versus 97.5%[con]. Egg contents and eggshells were generally contaminated to a lesser extent, primarily with Enterococcus spp. Listeria isolates were susceptible to almost all tested antibiotics, only three Listeria innocua from conventional keepings were resistant to clindamycin; one isolate additionally to imipenem. High percentages of Enterococcus faecalis were resistant to doxycycline and macrolides. Enterococcus faecium proved to have high resistance rates to clindamycin, fosfomycin and erythromycin; 9.1% were even resistant to the reserve antibiotic synercid. Further, Enterococcus spp. showed higher resistance rates to doxycycline, erythromycin, fosfomycin and rifampicin. No glycopeptide resistant enterococci were detected. A correlation between keeping system and resistance/susceptibility rates could be demonstrated. In detail, E. faecalis from organic laying hen husbandries showed significant lower resistance prevalences to tylosin, streptomycin and doxycycline; susceptibility rates were higher for enrofloxacin and ciprofloxacin. Rifampicin and imipenem were more effective in isolates from conventional keepings (P < 0.05). The amounts of resistant isolates of the Enterococcus raffinosus from organic farms were significantly lower, the amounts of sensitive isolates were significantly higher than from conventional farms concerning eight antibiotics (P < 0.05). When comparing the susceptibility/resistance rates, as well as the mean minimum

STREPTOMYCETE Producing Antibiotics Isolated From Egyptian Soil

International Nuclear Information System (INIS)

SALAMA, S.M; MAHMOUD, S.M; ELKABBANY, H.M.

2010-01-01

An investigation was concerned the distribution of Streptomyces species in some types of Egyptian soils. Thirty nine actinomycetes isolates were obtained from 7 types of Egyptian soils; 8 isolates exhibited antimicrobial activities against all tested organisms and three of them were identified as Streptomyces griseoluteus (YM23), Streptomyces aurantiogriseus (S15) and Streptomyces nogalator (H12). RAPD-PCR showed correlation between 8 isolates in 3 clades. The active metabolite was extracted with ethyl acetate and concentrated in vacuum and the crude fraction was purified using thin layer and column chromatography

Influence of culture conditions for clinically isolated non-albicans Candida biofilm formation.

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Tan, Yulong; Leonhard, Matthias; Ma, Su; Schneider-Stickler, Berit

2016-11-01

Non-albicans Candida species have been isolated in increasing numbers in patients. Moreover, they are adept at forming biofilms. This study analyzed biofilm formation of clinically isolated non-albicans Candida, including Candida tropicalis, Candida krusei and Candida parapsilosis under the influence of different growth media (RPMI 1640, YPD and BHI) and several culture variables (inoculum concentration, incubation period and feeding conditions). The results showed that culture conditions strongly influenced non-albicans Candida species biofilm formation. YPD and BHI resulted in larger amount of biofilm formation with higher metabolic activity of biofilms. Furthermore, the growth media seems to have varying effects on adhesion and biofilm development. Growth conditions may also influence biofilm formation, which was enhanced when starting the culture with a larger inoculum, longer incubation period and using a fed-batch system. Therefore, the potential influences of external environmental factors should be considered when studying the non-albicans Candida biofilms in vitro. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of acaricidal components isolated from lettuce (Lactuca sativa) on carmine spider mite (Tetranychus cinnabarinus Boisd.).

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Li, M; Zhang, Y; Ding, W; Luo, J; Li, S; Zhang, Q

2018-06-01

This study aimed to evaluate the acaricidal activity of lettuce (Lactuca sativa) extracts against carmine spider mites (Tetranychus cinnabarinus Boisd.) and isolate the acaricidal components. Acaricidal activities of lettuce extracts isolated from different parts (the leaf, root and seed) using various solvents (petroleum ether, acetone and methanol) were evaluated with slide-dip bioassay and relatively high median lethal concentration (LC50) values were detected. Acetone extracts of lettuce leaves harvested in July and September were fractionated and isolated with silica gel and thin-layer chromatography. Consequently, acetone extracts of lettuce leaves harvested in July exhibited higher acaricidal activity than those harvested in September, with an LC50 value of 0.268 mg ml-1 at 72 h post-treatment. A total of 27 fractions were obtained from the acetone extract of lettuce leaves harvested in July, and mite mortalities with the 11th and 12th fractions were higher than those with the other 25 fractions (LC50: 0.751 and 1.258 mg ml-1 at 48 h post-treatment, respectively). Subsequently, active acaricidal components of the 11th fraction were identified by infrared, nuclear magnetic resonance and liquid chromatography/mass spectrometry. Five components were isolated from the 11th fraction, with components 11-a and 11-b showing relatively high acaricidal activities (LC50: 0.288 and 0.114 mg ml-1 at 48 h post-treatment, respectively). Component 11-a was identified as β-sitosterol. In conclusion, acetone extracts of lettuce leaves harvested in July might be used as a novel phytogenic acaricide to control mites.

Isolation of quercetin from the methanolic extract of Lagerstroemia speciosa by HPLC technique, its cytotoxicity against MCF-7 cells and photocatalytic activity.

Science.gov (United States)

Sai Saraswathi, V; Saravanan, D; Santhakumar, K

2017-06-01

The flavonoids present in the leaves of Lagerstroemia speciosa were extracted, characterized by spectral methods and studied for its cytotoxicity activity against MCF-cell lines and photocatalytic activity against azo dye. Direct and sequential soxhlet extraction was performed and its concentrated crude extract was subjected to high performance liquid chromatography. The yield obtained by the isolated compound (MEI-quercetin) from leaves of L. speciosa was found to be 1.8g from the methanolic extract. The phytochemical analysis and the Rf value of the isolated flavonoid was found to be 3.59. The isolated compound was characterized by Infrared Spectroscopy, NMR and Mass. Based on the characterization, the structure was elucidated as quercetin - a flavonoid. The isolated compound showed the significant in vitro cytotoxicity activity against MCF-7 cell lines at 500μg/ml when compared to the crude extract. Among the various concentrations (25, 50, 100, 250, and 500μg/ml), at higher concentration the cell viability was pronounced and also compared with that of the control. It was first time to report that the isolated flavonoid showed photocatalytic against azo dye-methyl orange. The dye degradation was monitored by UV-Vis spectrophotometry. The isolated compound showed dye degradation of 91.66% with the crude extract 82.47% at 160min. Hence in the present findings, the photocatalytic degradation of MO dye under UV irradiation was investigated over isolated compound of L. speciosa. Hence we expect that this can be used to treat the waste water in near future based on the photocatalytic technique. Copyright © 2017 Elsevier B.V. All rights reserved.

Evidence of adaptive tolerance to nickel in isolates of Cenococcum geophilum from serpentine soils.

Science.gov (United States)

Gonçalves, Susana C; Martins-Loução, M Amélia; Freitas, Helena

2009-04-01

Selection for metal-tolerant ecotypes of ectomycorrhizal (ECM) fungi has been reported in instances of metal contamination of soils as a result of human activities. However, no study has yet provided evidence that natural metalliferous soils, such as serpentine soils, can drive the evolution of metal tolerance in ECM fungi. We examined in vitro Ni tolerance in isolates of Cenococcum geophilum from serpentine and non-serpentine soils to assess whether isolates from serpentine soils exhibited patterns consistent with adaptation to elevated levels of Ni, a typical feature of serpentine. A second objective was to investigate the relationship between Ni tolerance and specific growth rates (micro) among isolates to increase our understanding of possible tolerance/growth trade-offs. Isolates from both soil types were screened for Ni tolerance by measuring biomass production in liquid media with increasing Ni concentrations, so that the effective concentration of Ni inhibiting fungal growth by 50% (EC(50)) could be determined. Isolates of C. geophilum from serpentine soils exhibited significantly higher tolerance to Ni than non-serpentine isolates. The mean Ni EC(50) value for serpentine isolates (23.4 microg ml(-1)) was approximately seven times higher than the estimated value for non-serpentine isolates (3.38 microg ml(-1)). Although there was still a considerable variation in Ni sensitivity among the isolates, none of the serpentine isolates had EC(50) values for Ni within the range found for non-serpentine isolates. We found a negative correlation between EC(50) and micro values among isolates (r = -0.555). This trend, albeit only marginally significant (P = 0.06), indicates a potential trade-off between tolerance and growth, in agreement with selection against Ni tolerance in "normal" habitats. Overall, these results suggest that Ni tolerance arose among serpentine isolates of C. geophilum as an adaptive response to Ni exposure in serpentine soils.

Production of nanodrug for Bacillus cereus isolated from HIV positive patient using Mallotus philippensis

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R. Bhuvaneswari

2016-04-01

Full Text Available The present investigation was aimed to synthesis of silver nanoparticles (AgNPs using Mallotus philippensis leaf extract and their antibacterial potential against Bacillus cereus isolated from HIV positive patient. In this, UV- Visible spectroscopy showed the high peak of absorption band at 450 nm. Based on XRD analysis, face centered cubic structure and average size of the AgNPs was around 16 nm. FTIR spectroscopy study revealed the seventeen functional groups of the AgNPs was observed. The morphology of AgNPs was spherical, oval shapes and diameter of the particle size ranges between 9 and 24 nm was measured using transmission electron microscopy (TEM. In addition to these green synthesized AgNPs were found to express the higher efficacy in inhibiting the growth of Bacillus cereus (B. cereus isolated from the HIV-positive patient.

Potential virulence of Klebsiella sp. isolates from enteral diets

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S.C.L. Pereira

2015-01-01

Full Text Available We aimed to evaluate the potential virulence of Klebsiella isolates from enteral diets in hospitals, to support nosocomial infection control measures, especially among critical-care patients. Phenotypic determination of virulence factors, such as capsular expression on the external membrane, production of aerobactin siderophore, synthesis of capsular polysaccharide, hemolytic and phospholipase activity, and resistance to antibiotics, which are used therapeutically, were investigated in strains of Klebsiella pneumoniae and K. oxytoca. Modular industrialized enteral diets (30 samples as used in two public hospitals were analyzed, and Klebsiella isolates were obtained from six (20% of them. The hypermucoviscous phenotype was observed in one of the K. pneumoniae isolates (6.7%. Capsular serotypes K1 to K6 were present, namely K5 and K4. Under the conditions of this study, no aerobactin production, hemolytic activity or lecithinase activity was observed in the isolates. All isolates were resistant to amoxicillin and ampicillin and sensitive to cefetamet, imipenem, chloramphenicol, gentamicin and sulfamethoxazole-trimethoprim. Most K. pneumoniae isolates (6/7, 85.7% from hospital B presented with a higher frequency of resistance to the antibiotics tested in this study, and multiple resistance to at least four antibiotics (3/8; 37.5% compared with isolates from Hospital A. The variations observed in the antibiotic resistance profiles allowed us to classify the Klebsiella isolates as eight antibiotypes. No production of broad-spectrum β-lactamases was observed among the isolates. Our data favor the hypothesis that Klebsiella isolates from enteral diets are potential pathogens for nosocomial infections.

Molecular epidemiology of Klebsiella pneumoniae K1 and K2 isolates in Japan.

Science.gov (United States)

Harada, Sohei; Ishii, Yoshikazu; Saga, Tomoo; Aoki, Kotaro; Tateda, Kazuhiro

2018-03-20

Although severe infections caused by hypervirulent Klebsiella pneumoniae isolates, such as K1 isolates belonging to sequence type (ST) 23, have been a significant problem in Asian countries, epidemiology of these isolates in Japan remains unclear. We performed a nationwide molecular epidemiological study of K. pneumoniae K1 and K2 isolates in Japan. Of the 259K. pneumoniae isolates collected, 14 and 16 isolates were identified as capsular genotypes K1 and K2, respectively. All K1 isolates were ST23 or its closely related clones and showed high genetic similarity by pulsed-field gel electrophoresis (PFGE) and the DiversiLab system (DL). K2 isolates, belonging to ST14, ST25, ST65, ST86, and ST110, were more genetically diverse than K1 isolates. Isolates belonging to a specific ST showed identical virulence gene profiles with a few exceptions. PFGE and DL results using K1 and K2 isolates were generally in agreement. Copyright © 2018. Published by Elsevier Inc.

Isolation and identification of citrus psorosis virus Egyptian isolate (CPsV-EG).

Science.gov (United States)

Ghazal, S A; El-Dougdoug, Kh A; Mousa, A A; Fahmy, H; Sofy, A R

2008-01-01

Citrus psorosis ophiovirus (CPsV), is considered to be of the most serious and deter mental virus pathogen's citrus species trees in Egypt. CPsV-EG was isolated from infected citrus grapefruit (C. paradisi Macf.) at Agric. Res. Centre (ARC). The grapefruit which used for CPsV-EG isolate was found to be free from CTV, CEVd and Spiroplasma citri where as gave -ve results with DTBIA, tissue print hybridization and Diene's stain respectively. CPsV-EG was detected on the basis of biological indexing by graft inoculation which gave oak leaf pattern (OLP) on Dweet tangor and serological assay by DAS-ELISA using Mab specific CPsV. CPsV-EG was reacted with variable responses on 16 host plants belonging to 6 families. Only 8 host plants are susceptible and showed visible external symptoms which appeared as local, systemic and local followed by systemic infections. CPsV-EG isolate was transmitted from infected citrus to citrus by syringe and grafting and herbaceous plants by forefinger inoculation and syringe. The woody indicators and rootstocks were differed in response to CPsV-EG isolate which appeared as no-response, response, sensitivity and hypersensitivity. The serological characters represented as the antigenic determinants of CPsV-EG isolate related to monoclonal antibodies specific CPsV strain where as appeared precipitation reaction by DAS-ELISA and DTBIA. The partial fragment of RNA3 (coat protein gene) of CPsV-EG (-1140bp and -571bp) was amplified by reverse transcription-polymerase chain reaction (RT-PCR) from grapefruit tissues using two sets primers specific CPsV (CPV3 and CPV4) and (PS66 and PS65) respectively. The virus under study was identified as CPsV-EG isolate according to biological, serological and molecular characters.

New nanostructured silica incorporated with isolated Ti material for the photocatalytic conversion of CO2 to fuels

Science.gov (United States)

2014-01-01

In this work, new nanoporous silica (Korea Advanced Institute of Science and Technology-6 (KIT-6)-dried or KIT-6-calcined) incorporated with isolated Ti materials with different Si/Ti ratios (Si/Ti = 200, 100, and 50) has been synthesized and investigated to establish photocatalytic reduction of CO2 in the presence of H2O vapors. The properties of the materials have been characterized through N2 adsorption/desorption, UV-vis, TEM, FT-IR, and XPS analysis techniques. The intermediate amount of the isolated Ti (Si/Ti = 100) has resulted to be more uniformly distributed on the surface and within the three-dimensional pore structure of the KIT-6 material, without its structure collapsing, than the other two ratios (Si/Ti = 200 and 50). However, titania agglomerates have been observed to have formed due to the increased Ti content (Si/Ti = 50). The Ti-KIT-6 (calcined) materials in the reaction showed higher activity than the Ti-KIT-6 (dried) materials, which produced CH4, H2, CO, and CH3OH (vapors) as fuel products. The Ti-KIT-6 (Si/Ti = 100) material also showed more OH groups, which are useful to obtain a higher production rate of the products, particularly methane, which was even higher than the rate of the best commercial TiO2 (Aeroxide P25, Evonik Industries AG, Essen, Germany) photocatalyst. PMID:24690396

Food insecurity and mental illness: disproportionate impacts in the context of perceived stress and social isolation.

Science.gov (United States)

Martin, M S; Maddocks, E; Chen, Y; Gilman, S E; Colman, I

2016-03-01

Food insecurity is associated with elevated risk of mental illness. This risk may be further compounded by stressful life events and by social isolation. This study investigated whether the risk of mental illness is higher among individuals experiencing food insecurity along with greater stress and social isolation. Cross-sectional self-report survey data from the 2009-10 Canadian Community Health Survey (N = 100,401). We estimated prevalence differences of the risk of self-reported mental illness associated with food insecurity alone and in combination with stressful life events and social isolation. Sensitivity analyses were conducted on a sub-sample who completed a structured diagnostic interview. Overall, the prevalence of mental illness was 18.4% [95% CI 16.7-20.1] higher for women and 13.5% higher [95% CI 11.9, 15.2] for men in severely food insecure households compared to those reporting food security. The increased risk of mental illness associated with food insecurity was more pronounced among females and those reporting higher stress and social isolation. Individuals reporting food insecurity are at increased risk of mental illness. This increased risk is further exacerbated in high stress and socially isolated environments. Policies, clinical and public health interventions must address broader constellations of risks that exist when food insecurity is present. Copyright © 2015 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Genotypic and phenotypic diversity of Alicyclobacillus acidocaldarius isolates.

Science.gov (United States)

Félix-Valenzuela, L; Guardiola-Avila, I; Burgara-Estrella, A; Ibarra-Zavala, M; Mata-Haro, V

2015-10-01

The fruit juice industry recognizes Alicyclobacillus as a major quality control target micro-organism. In this study, we analysed 19 bacterial isolates to identify Alicyclobacillus species by polymerase chain reaction (PCR) and sequencing analyses. Phenotypic and genomic diversity among isolates were investigated by API 50CHB system and ERIC-PCR (enterobacterial repetitive intergenic consensus-PCR) respectively. All bacterial isolates were identified as Alicyclobacillus acidocaldarius, and almost all showed identical DNA sequences according to their 16S rRNA (rDNA) gene partial sequences. Only few carbohydrates were fermented by A. acidocaldarius isolates, and there was little variability in the biochemical profile. Genotypic fingerprinting of the A. acidocaldarius isolates showed high diversity, and clusters by ERIC-PCR were distinct to those obtained from the 16S rRNA gene phylogenetic tree. There was no correlation between phenotypic and genotypic variability in the A. acidocaldarius isolates analysed in this study. Detection of Alicyclobacillus strains is imperative in fruit concentrates and juices due to the production of guaiacol. Identification of the genera originates rejection of the product by processing industry. However, not all the Alicyclobacillus species are deteriorative and hence the importance to differentiate among them. In this study, partial 16S ribosomal RNA sequence alignment allowed the differentiation of species. In addition, ERIC-PCR was introduced for the genotypic characterization of Alicyclobacillus, as an alternative for differentiation among isolates from the same species. © 2015 The Society for Applied Microbiology.

Antagonistic bioactivity of endophytic strains isolated from Salvia ...

African Journals Online (AJOL)

The antibiotic-producing potential of endophytic populations from medical plant of Salvia miltiorrhiza was examined. A total of 63 isolates was screened against five fungal and three bacterial species for the production of antimicrobial compounds. It showed that more isolates was antagonistic to fungi than to bacteria.

Biological activity of some bacterial isolates against soil borne pathogenic fungi

International Nuclear Information System (INIS)

Makbol, H.; Refae, R.I.; Eid, H.A.; Mohamed, O.M.

2011-01-01

The antagonistic activity of three bacterial isolates namely Micro bacterium terregens, Cellulosimicrobium cellulans and Bacillus amyloliquefaciens was evaluated through direct confrontation method and filtrates culture against the growth of Fusarium solani, Fusarium oxysporum, Rhizoctonia solani and Phytophthra cactorum. All bacterial isolates showed the inhibition of the mycelia growth of the isolated fungi as resulting to confrontation methods except R. solani with C. cellulans that showed no inhibitory effect and energized the low activity with B. amyloliquefaciens. Culture filtrate of different bacterial isolates after different incubation periods revealed that the highest antifungal activity between 3-10 days

Growth in serum-free medium improves isolation of Chlamydia pneumoniae.

OpenAIRE

Maass, M; Essig, A; Marre, R; Henkel, W

1993-01-01

Infectivity titers were determined for eight Chlamydia pneumoniae strains simultaneously grown in serum-free and serum-supplemented cell culture media. Use of serum-free medium resulted in a 10- to 50-fold increase in the susceptibility of HL cells to chlamydial infection. Comparative primary isolation of a wild-type strain also produced higher inclusion counts in a serum-free environment. Serum-free cultivation is recommended to increase the efficiency of C. pneumoniae isolation from clinica...

Multidrug-Resistance and Toxic Metal Tolerance of Medically Important Bacteria Isolated from an Aquaculture System

Science.gov (United States)

Resende, Juliana Alves; Silva, Vânia L.; Fontes, Cláudia Oliveira; Souza-Filho, Job Alves; de Oliveira, Tamara Lopes Rocha; Coelho, Cíntia Marques; César, Dionéia Evangelista; Diniz, Cláudio Galuppo

2012-01-01

The use of antimicrobials and toxic metals should be considered carefully in aquaculture and surrounding environments. We aimed to evaluate medically relevant bacteria in an aquaculture system and their susceptibility to antimicrobials and toxic metals. Selective cultures for enterobacteria (ENT), non-fermenting Gram-negative rods (NFR) and Gram-positive cocci (GPC) were obtained from water samples collected in two different year seasons. The isolated bacteria were biochemically identified and antimicrobial and toxic metal susceptibility patterns were determined. Overall, 407 representative strains were recovered. In general, bacteria isolated from fish ponds showed higher multiple antibiotic resistance indices when compared to those isolated from a water-fed canal. Resistance to penicillin and azithromycin was observed more frequently in the GPC group, whereas resistance to ampicillin and ampicillin/sulbactam or gentamicin was observed more frequently in the ENT and NFR groups, respectively. All the isolated bacteria were tolerant to nickel, zinc, chromium and copper at high levels (≥1,024 μg mL−1), whereas tolerance to cadmium and mercury varied among the isolated bacteria (2–1,024 μg mL−1). Multidrug-resistant bacteria were more frequent and diverse in fish ponds than in the water-fed canal. A positive correlation was observed between antimicrobial resistance and metal tolerance. The data point out the need for water treatment associated with the aquaculture system. PMID:22972388

The prevalence of virulence genes of E. coli strains isolated from children with urinary tract infection

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Farshad Shohreh

2009-01-01

Full Text Available To evaluate the prevalence of virulence genes in E. coli strains isolated from urine samples of children with urinary tract infection(UTI and their correlation with clinical data, we iso-lated E. coli strains from urine samples of children with UTI during the period of August 2005 - August 2006 and studied them for the presence of the virulence genes by PCR. A total of 96 E. coli strains were isolated. The prevalence of genes, pyelonephritis associated pili (pap genes, S-family adhesions (sfa gene, hemolysin (hly gene, and cytotoxic nercotizing factor type 1 (cnf-1-1 gene among the isolated strains was 27.1%, 14.6%, 13.5% and 22.9 %, respectively. Pyelonephritis was more prevalent in the cases with positive virulence genes. The results showed significant correlation bet-ween age of the patient and the presence of the genes (P< 0.05. Cnf-1 gene was significantly more common in samples of patients with abnormal finding on the ultrasound of kidneys (P= 0.049. Our study demonstrated higher prevalence of pyelonephritis in the presence of E. coli virulence genes. Detection of the genes in urine samples may help in the management of UTI.

The prevalence of virulence genes of E. coli strains isolated from children with urinary tract infection

International Nuclear Information System (INIS)

Farshad, Shohreh; Emamghorashi, Fatemeh

2009-01-01

To evaluate the prevalence of virulence genes in E. coli strains isolated from urine samples of children with urinary tract infection(UTI) and their correlation with clinical data, we isolated E. coli strains from urine samples of children with UTI during the period of August 2005 - August 2006 and studied them for the presence of the virulence genes by PCR. A total of 96 E. coli strains were isolated. The prevalence of genes, pyelonephritis associated pili (pap genes), S-family adhesions (sfa gene), hemolysin (hly gene), and cytotoxic nercotizing factor type 1 (cnf-1-1 gene) among the isolated strains was 27.1%, 14.6%, 13.5% and 22.9 %, respectively. Pyelonephritis was more prevalent in the cases with positive virulence genes. The results showed significant correlation between age of the patient and the presence of the genes (P< 0.05). Cnf-1 gene was significantly more common in samples of patients with abnormal finding on the ultrasound of kidneys (P0.049). Our study demonstrated higher prevalence of pyelonephritis in the presence of E. coli virulence genes. Detection of the genes in urine samples may help in the management of UTI. (author)

Metallo-β-lactamase-producing clinical isolates from patients of a tertiary care hospital

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Durgesh Gopalrao Deshmukh

2011-01-01

Results: Of 638 gram negative bacilli isolates and 3.39% showed imipenem resistance, 2.9% showed MBL production, of which 1.7% were non-fermenters and 1.25% were Enterobacteriaceae, 0.3% showing non-MBL KPC carbapenemas. Most isolates were from the intensive care unit and from post-operative patients. Our findings show that there are significant numbers of isolates having MBL production along with multidrug resistance. There is a need for active surveillance to detect MBL producers.

Characterization of Clostridium perfringens isolated from mammals and birds from Guwahati city, India

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Mafruza S Rahman

2012-01-01

Full Text Available Of the 102 samples collected from mammals and birds, both domestic and captive wild, 48 were found to be positive for Clostridium perfringens. Most of the mammal isolates (84.38% appeared to have been collected from clinically affected animals, while 33.33% of the bird samples were from clinically affected and 21.43% from apparently healthy birds infected with C. perfringens. Isolates revealed high sensitivity to ciprofloxacin, enrofloxacin and norfloxacin. Among the isolated C. perfringens, 30 (62.50% showed DNase production. Hemolytic activity was recorded in 14 (24.16% of the isolates and 28 (58.33% showed phospholipase C production. All the phospholipase C positive isolates revealed the presence of cpa gene encoding alpha (α toxin. Of the 102 samples collected from mammals and birds, both domestic and captive wild, 48 were found to be positive for Clostridium perfringens. Most of the mammal isolates (84.38% appeared to have been collected from clinically affected animals, while 33.33% of the bird samples were from clinically affected and 21.43% from apparently healthy birds infected with C. perfringens. Isolates revealed high sensitivity to ciprofloxacin, enrofloxacin and norfloxacin. Among the isolated C. perfringens, 30 (62.50% showed DNase production. Hemolytic activity was recorded in 14 (24.16% of the isolates and 28 (58.33% showed phospholipase C production. All the phospholipase C positive isolates revealed the presence of cpa gene encoding α toxin.

Genetic Variability of Macrophomina phaseolina Isolates from Dry Beans in Turkey

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Serkan Yeşil

2016-04-01

Full Text Available Charcoal rot is a soil and seed borne, economically important fungal disease on dry bean in Turkey. Twenty bean isolates of M. phaseolina collected from different locations in Turkey during 2008 and 2012 years were studied for genetic variability using random amplified polymorphic DNA (RAPD assay, chlorate sensitivity on medium supplemented with 120mM of potassium, phenotype of colony, and pathogenicity. Isolates were identified as M. phaseolina based on morhological features and PCR assays using species-specific primers (MPKF1and MPKR1. Isolates of M. phaseolina were analysed for their aggressiveness on the susceptible bean cv. Akman 98, by soil inoculation method. Isolates exhibiting a dense chlorate phenotype were chlorate-resistant, while those possessing feathery and restricted chlorate phenotypes were chlorate-sensitive. More than half of the isolates (55% were resistant to chlorate and produced dense phenotype, while 35% isolates showed feathery and two isolates (10% showed restricted growth. DNA from 20 isolates was subjected to genetic diversity analysis by the RAPD method using 14 randomly chosen 10-base random primers, and low genetic diversity (33.3% was observed among the tested isolates.

The Role of Isolation Methods on a Nanoscale Surface Structure and Its Effect on the Size of Exosomes

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JungReem Woo

2016-06-01

Full Text Available Exosomes are ~100 nanometre diameter vesicles secreted by mammalian cells. These emerging disease biomarkers carry nucleic acids, proteins and lipids specific to the parental cells that secrete them. Exosomes are typically isolated in bulk by ultracentrifugation, filtration or immu‐ noaffinity precipitation for downstream proteomic, genomic, or lipidomic analysis. However, the structural properties and heterogeneity of isolated exosomes at the single vesicle level are not well characterized due to their small size. In this paper, by using high-resolution atomic force microscope imaging, we show the nanoscale mor‐ phology and structural heterogeneity in exosomes derived from U87 cells. Quantitative assessment of single exosomes reveals nanoscale variations in morphology, surface roughness and counts isolated by ultracentrifugation (UC and immunoaffinity (IA purification. Both methods produce intact globular, 30-120 nm sized vesicles when imaged under fluid and in air. However, IA exosomes had higher surface roughness and bimodal size population compared to UC exosomes. The study highlights the differences in size and surface topography of exosomes purified from a single cell type using different isolation methods.

Sensitivity of some local isolates of Mycoplasma gallisepticum against antibiotics

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Sutiastuti Wahyuwardani

1998-03-01

Full Text Available Sensitivity of five local isolates ofMycoplasma gallisepticum (MG strain and two standard MG isolates obtained from Australia were tested against antibiotics of oxytetracycline, doxycycline, erythromycin, bacitracin, vancomycin, methicillin and penicillin using antibiogram disc method. The result showed that one, 2 and 3 local MG isolates were resistent to doxycycline, erythromycin and oxytetracycline respectively . MG isolate of ADA7 from Australia was found to be resistent to all antibiotics tested. None ofthe local MG isolates were sensitive against bacitracin, vancomycin, methicillin and penicillin.

Spectrum and Sensitivity of Bacterial Keratitis Isolates in Auckland

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S. Marasini

2016-01-01

Full Text Available Background. The bacteria isolated from severe cases of keratitis and their antibiotic sensitivity are recognised to vary geographically and over time. Objectives. To identify the most commonly isolated bacteria in keratitis cases admitted over a 24-month period to a public hospital in Auckland, New Zealand, and to investigate in vitro sensitivity to antibiotics. Methods. Hospital admissions for culture-proven bacterial keratitis between January 2013 and December 2014 were identified. Laboratory records of 89 culture positive cases were retrospectively reviewed and antibiotic sensitivity patterns compared with previous studies from other NZ centres. Results. From 126 positive cultures, 35 species were identified. Staphylococcus was identified to be the most common isolate (38.2%, followed by Pseudomonas (21.3%. Over the last decade, infection due to Pseudomonas species, in the same setting, has increased (p≤0.05. Aminoglycosides, cefazolin, ceftazidime, erythromycin, tetracycline, and doxycycline were 100% effective against tested isolates in vitro. Amoxicillin (41.6%, cefuroxime (33.3%, and chloramphenicol (94.7% showed reduced efficacy against Gram-negative bacteria, whereas penicillin (51% and ciprofloxacin (98.8% showed reduced efficacy against Gram-positive bacteria. Conclusions. Despite a shift in the spectrum of bacterial keratitis isolates, antibiotic sensitivity patterns have generally remained stable and show comparability to results within the last decade from NZ centres.

Spectrum and Sensitivity of Bacterial Keratitis Isolates in Auckland.

Science.gov (United States)

Marasini, S; Swift, S; Dean, S J; Ormonde, S E; Craig, J P

2016-01-01

Background. The bacteria isolated from severe cases of keratitis and their antibiotic sensitivity are recognised to vary geographically and over time. Objectives. To identify the most commonly isolated bacteria in keratitis cases admitted over a 24-month period to a public hospital in Auckland, New Zealand, and to investigate in vitro sensitivity to antibiotics. Methods. Hospital admissions for culture-proven bacterial keratitis between January 2013 and December 2014 were identified. Laboratory records of 89 culture positive cases were retrospectively reviewed and antibiotic sensitivity patterns compared with previous studies from other NZ centres. Results. From 126 positive cultures, 35 species were identified. Staphylococcus was identified to be the most common isolate (38.2%), followed by Pseudomonas (21.3%). Over the last decade, infection due to Pseudomonas species, in the same setting, has increased (p ≤ 0.05). Aminoglycosides, cefazolin, ceftazidime, erythromycin, tetracycline, and doxycycline were 100% effective against tested isolates in vitro. Amoxicillin (41.6%), cefuroxime (33.3%), and chloramphenicol (94.7%) showed reduced efficacy against Gram-negative bacteria, whereas penicillin (51%) and ciprofloxacin (98.8%) showed reduced efficacy against Gram-positive bacteria. Conclusions. Despite a shift in the spectrum of bacterial keratitis isolates, antibiotic sensitivity patterns have generally remained stable and show comparability to results within the last decade from NZ centres.

Spectrum and Sensitivity of Bacterial Keratitis Isolates in Auckland

Science.gov (United States)

Swift, S.; Dean, S. J.; Ormonde, S. E.

2016-01-01

Background. The bacteria isolated from severe cases of keratitis and their antibiotic sensitivity are recognised to vary geographically and over time. Objectives. To identify the most commonly isolated bacteria in keratitis cases admitted over a 24-month period to a public hospital in Auckland, New Zealand, and to investigate in vitro sensitivity to antibiotics. Methods. Hospital admissions for culture-proven bacterial keratitis between January 2013 and December 2014 were identified. Laboratory records of 89 culture positive cases were retrospectively reviewed and antibiotic sensitivity patterns compared with previous studies from other NZ centres. Results. From 126 positive cultures, 35 species were identified. Staphylococcus was identified to be the most common isolate (38.2%), followed by Pseudomonas (21.3%). Over the last decade, infection due to Pseudomonas species, in the same setting, has increased (p ≤ 0.05). Aminoglycosides, cefazolin, ceftazidime, erythromycin, tetracycline, and doxycycline were 100% effective against tested isolates in vitro. Amoxicillin (41.6%), cefuroxime (33.3%), and chloramphenicol (94.7%) showed reduced efficacy against Gram-negative bacteria, whereas penicillin (51%) and ciprofloxacin (98.8%) showed reduced efficacy against Gram-positive bacteria. Conclusions. Despite a shift in the spectrum of bacterial keratitis isolates, antibiotic sensitivity patterns have generally remained stable and show comparability to results within the last decade from NZ centres. PMID:27213052

Genetic diversity of tomato-infecting Tomato yellow leaf curl virus (TYLCV) isolates in Korea.

Science.gov (United States)

Kim, Sue Hoon; Oh, Sung; Oh, Tae-Kyun; Park, Jae Sung; Kim, Sei Chang; Kim, Seong Hwan; Kim, Young Shik; Hong, Jeum Kyu; Sim, Sang-Yun; Park, Kwon Seo; Lee, Hwan Gu; Kim, Kyung Jae; Choi, Chang Won

2011-02-01

Epidemic outbreaks of Tomato yellow leaf curl virus (TYLCV) diseases occurred in greenhouse grown tomato (Solanum lycopersicum) plants of Busan (TYLCV-Bus), Boseong (TYLCV-Bos), Hwaseong (TYLCV-Hwas), Jeju Island (TYLCV-Jeju), and Nonsan (TYLCV-Nons) in Korea during 2008-2009. Tomato disease by TYLCV has never occurred in Korea before. We synthesized the full-length genomes of each TYLCV isolate from the tomato plants collected at each area and determined their nucleotides (nt) sequences and deduced the amino acids of six open reading frames in the genomes. TYLCV-Bus and -Bos genomes shared higher nt identities with four Japanese isolates -Ng, -Omu, -Mis, and -Miy. On the other hand, TYLCV-Hwas, -Jeju, and -Nons genomes shared higher nt identities with five Chinese isolates TYLCV-AH1, -ZJ3, -ZJHZ12, -SH2, -Sh10, and two Japanese isolates -Han and -Tosa. On the basis of a neighbor-joining tree, five Korean TYLCV isolates were separated into three clades. TYLCV-Bus and -Bos formed the first clade, clustering with four Japanese isolates TYLCV-Mis, -Omu, -Ng, and -Miy. TYLCV-Jeju and -Nons formed the second clade, clustering with two Chinese isolates -ZJHZ212 and -Sh10. TYLCV-Hwas was clustered with two Japanese isolates -Han and -Tosa and three Chinese isolates -AH1, -ZJ3, and -SH2. Two fragments that had a potentially recombinant origin were identified using the RDP, GENECONV, BootScan, MaxChi, Chimaera, SiScan, and 3Seq methods implemented in RDP3.41. On the basis of RDP analysis, all TYLCV isolates could originated from the interspecies recombination between TYLCV-Mld[PT] isolated from Portugal as a major parent and TYLCTHV-MM isolated from Myanmar as a minor parent.

Pheno- and genotyping of Staphylococcus epidermidis isolated from bovine milk and human skin

DEFF Research Database (Denmark)

Thorberg, B. M.; Kuhn, I.; Aarestrup, Frank Møller

2006-01-01

showed one pattern, which was identical to the most common pattern found in the milk isolates. Isolates from herd 2 showed three to four patterns, two of these being identical to skin isolates from the milker. As dairy cows are not a natural host for S. epidermidis the results suggest a human source...... (PFGE) and 122 by ribotyping. PFGE showed single patterns in the human strains with one exception; one strain was categorised as the same clone as four of the milk strains. PFGE divided 73 of the milk strains into 62 different patterns. The PFGE method had high discriminatory power and shows that many...... different S. epidermidis types exist in milk samples. Antibiotic resistance patterns matched the SmaI profiles closely in the two herds, but poorly in the routinely collected milk samples. Isolates from herd I showed one to five patterns, depending on the typing method used. Isolates from the milker's skin...

Three distinct clones of carbapenem-resistant Acinetobacter baumannii with high diversity of carbapenemases isolated from patients in two hospitals in Kuwait

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N.A. Al-Sweih

2012-02-01

Full Text Available Summary: Objectives: This study was undertaken to investigate the clonal relatedness of multidrug-resistant (MDR Acinetobacter baumannii isolates collected from patients in two teaching hospitals in Kuwait. Materials and methods: Clinically significant consecutive isolates of A. baumannii obtained from patients in the Mubarak (36 and Adan (58 hospitals over a period of 6 months were studied. These isolates were identified using molecular methods, and their antimicrobial susceptibility was determined by the Etest method. The mechanism of resistance to carbapenem was investigated by PCR, and pulsed-field gel electrophoresis (PFGE was used to determine the clonal relatedness of MDR isolates. Results: Of the 94 isolates investigated, 80 (85.1% were multidrug resistant (MDR. The A. baumannii PFGE clone A and subclone A1 were the most prevalent in patients infected with MDR isolates. Fifty-five (94.8% and 15 (41.7% of the MDR isolates from the Adan and Mubarak hospitals, respectively, belonged to PFGE clone A; isolates in this group showed higher resistance rates to antibiotics than isolates form other groups. Of the 94 isolates, 40 (42.6% were resistant to either imipenem or meropenem or to both (CRAB. Most CRAB isolates (29/40 or 72.5% carried bla genes, which code for MBL (VIM-2 and IMP-1 enzymes. Two isolates harbored blaOXA-23. Conclusion: Three distinct clones of CRAB were isolated, providing evidence of a high diversity of carbapenemases among our geographically related isolates. Keywords: MDR A. baumannii, Genotypes, bla genes, Kuwait hospitals

Association between physical activity, participation in Physical Education classes, and social isolation in adolescents.

Science.gov (United States)

Santos, Simone José dos; Hardman, Carla Menêses; Barros, Simone Storino Honda; Santos da Franca, Carolina; Santos, Carolina da F B F; Barros, Mauro Virgilio Gomes de

2015-01-01

To analyze the association between physical activity, participation in Physical Education classes, and indicators of social isolation among adolescents. This was an epidemiological study based on secondary analysis of data from a representative sample of students (14-19 years) from public high schools (n=4,207). Data were collected through the questionnaire Global School-based Student Health Survey. The independent variables were the level of physical activity and enrollment in Physical Education classes, while the dependent variables were two indicators of social isolation (feeling of loneliness and having few friends). Descriptive and inferential procedures were used in the statistical analysis. Most of the adolescents were classified as insufficiently active (65.1%) and reported not attending Physical Education classes (64.9%). Approximately two in each ten participants reported feeling of loneliness (15.8%) and, in addition, about one in each five adolescents reported have only one friend (19.5%). In the bivariate analysis, a significantly lower proportion of individuals reporting social isolation was observed among adolescents who referred higher enrollment in Physical Education classes. After adjustment for confounding variables, binary logistic regression showed that attending Physical Education classes was identified as a protective factor in relation to the indicator of social isolation 'having few friends,' but only for girls. It was concluded that participation in Physical Education classes is associated with reduced social isolation among female adolescents. Copyright © 2015 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Isolation, Characterization and Anti-Inflammatory Property of Thevetia Peruviana

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R. Thilagavathi

2010-01-01

Full Text Available Thevetia peruviana seeds contain glucosides of neriifolin, acetylneriifolin and thevetin. Seed oil distillates of Thevetia peruviana have been found to contain anti-bacterial activity. In the persent work, the fresh flowers of Thevetia peruviana was subjected to phytochemical studies. The results of the study showed that the flowers contain quercetin, kaempferol and quercetin-7-o-galactoside. The structure of the isolated compound was characterized by UV, 1H NMR and 13C NMR spectra. The anti-inflammatory character of the isolated compound was tested by in vitro method and the results of the study revealed that the isolated compound showed a biphasic property.

Isolation and Characterization of a Bacteriophage Preying an Antifungal Bacterium

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Aryan Rahimi-Midani

2016-12-01

Full Text Available Several Bacillus species were isolated from rice field soils, and 16S rRNA gene sequence analysis showed that Bacillus cereus was the most abundant. A strain named BC1 showed antifungal activity against Rhizoctonia solani. Bacteriophages infecting strain BC1 were isolated from the same soil sample. The isolated phage PK16 had an icosahedral head of 100 ± 5 nm and tail of 200 ± 5 nm, indicating that it belonged to the family Myoviridae. Analysis of the complete linear dsDNA genome revealed a 158,127-bp genome with G + C content of 39.9% comprising 235 open reading frames as well as 19 tRNA genes (including 1 pseudogene. Blastp analysis showed that the proteins encoded by the PK16 genome had the closest hits to proteins of seven different bacteriophages. A neighbor-joining phylogenetic tree based on the major capsid protein showed a robust clustering of phage PK16 with phage JBP901 and BCP8-2 isolated from Korean fermented food.

Responses of an isolation system with distinct multiple frequencies

International Nuclear Information System (INIS)

Wu, Ting-shu; Seidensticker, R.W.

1991-01-01

Base isolation systems are generally designed with a single natural frequency. A major concern for these isolation systems is that, if the dominant frequency of a future earthquake is equal or close to the system's natural frequency, the ground motion will be greatly amplified because of resonance,and the superstructure would suffer severe damages. This paper present an isolation system designed with two distinct frequencies. Its responses to different ground motions, including a harmonic motion, show that no excessive amplification will occur. Adoption of this isolation system would greatly enhance the safety of an isolated superstructure against future strong earthquakes. 3 refs., 4 figs., 2 tabs

Globalisation and Higher Education

NARCIS (Netherlands)

Marginson, Simon; van der Wende, Marijk

2007-01-01

Economic and cultural globalisation has ushered in a new era in higher education. Higher education was always more internationally open than most sectors because of its immersion in knowledge, which never showed much respect for juridical boundaries. In global knowledge economies, higher education

Preliminary Study on Keratinase from Two Indonesian Isolates

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S Rahayu

2010-01-01

Full Text Available Keratinases (E.C.3.4.99.11 constitute a group of enzymes capable of disrupting the highly stable keratin structure consisting of disulphide, hydrogen, and hydrophobic bonds in the form of α-helices and β-sheets B. licheniformis MB-2 and Bacillus sp. MTS are two feather-degrading bacteria isolated from Tompaso crater at North Sulawesi and sulfuric land around Tangkuban Perahu in West Java. They were both capable of breaking down whole chicken feathers. In addition both isolates were capable of degrading other proteinous substrates rich in beta structure such as coccon, silk, human hair and fish scales. Result of fermentation experiment implied that addition of nitrogen sources (0.02% yeast extract and 0.02% tryptone to the basal medium increased keratinase production. Our experiments showed that keratinase production of Bacillus sp. MTS was higher and faster than that from B. licheniformis MB-2. Maximum extracellular keratinase activity of the enzyme derived from B. licheniformis was obtained during stationary phase at 72 h, while Bacillus sp. MTS was reached at 48 h. Disulfide reductase activity also detected in the extracellular fluid of Bacillus sp. MTS. The maximum condition for extracellular keratinase activity was 55oC and the enzyme showed two maximum pHs : pH 8.0 and pH 10. The zymogram analysis indicated sixth protein bands of 17, 25, 32, 53, 96 and 122 kD which were able to hydrolyze gelatin substrate in-situ. (Animal Production 12(1: 60-68 (2010Key Words : Bacillus, feather, keratinase, disulfide reductase

Preponderance of bacterial isolates in urine of HIV-positive malaria-infected pregnant women with urinary tract infection.

Science.gov (United States)

Ako-Nai, Kwashie Ajibade; Ebhodaghe, Blessing Itohan; Osho, Patrick; Adejuyigbe, Ebun; Adeyemi, Folasade Mubiat; Kassim, Olakunle O

2014-12-15

This study examined HIV and malaria co-infection as a risk factor for urinary tract infections (UTIs) in pregnancy. The study group included 74 pregnant women, 20 to 42 years of age, who attended the antenatal clinic at the Specialist Hospital at Akure, Ondo State, Nigeria. Forty-four of the pregnant women were either HIV seropositive with malaria infection (HIV+Mal+) or HIV seropositive without malaria (HIV+Mal-). The remaining thirty pregnant women served as controls and included women HIV seronegative but with malaria (HIV-Mal+) and women HIV seronegative without malaria. UTI was indicated by a bacterial colony count of greater than 10⁵/mL of urine, using cysteine lactose electrolyte deficient medium (CLED) as the primary isolation medium. Bacterial isolates were characterized using convectional bacteriological methods, and antibiotics sensitivity tests were carried out using the disk diffusion method. A total of 246 bacterial isolates were recovered from the cultures, with a mean of 3.53 isolates per subject. Women who were HIV+Mal+ had the most diverse group of bacterial isolates and the highest frequency of UTIs. The bacterial isolates from the HIV+Mal+ women also showed the highest degree of antibiotic resistance. While pregnancy and HIV infection may each represent a risk factor for UTI, HIV and malaria co-infection may increase its frequency in pregnancy. The higher frequency of multiple antibiotic resistance observed among the isolates, particularly isolates from HIV+Mal+ subjects, poses a serious public health concern as these strains may aggravate the prognosis of both UTI and HIV infection.

Biodegradation of Bonnylight crude oil by locally isolated fungi from oil contaminated soils in Akure, Ondo state

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Ekundayo, F.O.

2012-01-01

Full Text Available Aim: This present investigation was conducted to determine the capability of fungi isolated from soil samples collected from two automobile workshopsto bioremediate Bonnylight crude oil.Methodology and Results: The fungi present on the soil samples collected from two automobile workshops in Akure, Nigeria were investigated using standard microbiological techniques. These fungal isolates were screened for the ability to degrade Bonnylight crude oil. The bioremediation of Bonnylight crude oil was observed spectrophotometrically using the broth culture (non- harvested cells and harvested cells of the fungi isolated from the contaminated sites for a period of 20 days on minimal salt broth. Mycotypha microspora, Penicllium italicum, Botryris cinerea, Gliocladium deliquescence, Verticillium albo–atrum and Aspergillus niger were isolated from the contaminated site while Neurospora crassa, A. parasiticus, A. niger and Gonatobotryum apiculatum were isolated from uncontaminated sites. All the fungal isolates were capable of active degradation in varying degrees.Conclusion: The study shows that all the isolated fungi were capable of degrading the crude oil in varying degrees. The active crude oil utilizing fungi in this study were Aspergillus niger (both harvested and non harvested cells and Gliocladium deliquescence (non harvested cells and Penicillium italicum (harvested cells. Aspergillus niger has best degrading ability than other fungi in non harvested and harvested cell condition. However, non harvested cells recorded the higher degradative ability than harvested cells. Therefore, non harvested cells can be employed in bioremediation of Bonnylight crude oil.Significance and Impact of Study: The fungi isolated from automobile mechanic workshops contaminated soil can be exploited in the bioremediation of Bonny Light crude oil.

Study the effect of stable magnetic field on the inhibition activity of Saccharomyces boulardii against pathogenic bacteria isolated from urinary tract infection

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Nada Sabah Razouqi

2017-09-01

Full Text Available An increasing trend to use probiotic and study their effects on the pathogens has been conductor where they are defined as live micro-organisms that give a health benefit to the host when ingested in sufficient quantities, including the yeast Saccharomyces boulardii In addition research show that a magnetic field (MF has a biological effect. This study aims to investigate the effects of magnetic field on the inhibitory action of Saccharomyces boulardii against bacteria isolated from urinary tract infection, Study the sensitivity of bacterial isolates to antibiotics after diagnosis by microscopic, Cultural and biochemical examinations as well as Api20 E examinations were used gram negative bacteria , Most isolates were resistant to antibiotics elected, using Well diffusion method to investigate the inhibitory action of suspension and supernatant of the yeast with and without magnetic field in four different intensities (200-300-400-500 milli Tesla. The results show that inhibitory efficacy of each was higher wish increasing the magnetic field strength and differed in their impact depending on the type of bacteria and the isolate of K.pneumoniea was the most sensitive in all experiments, and suspension was more effective

Population Structure among Mycobacterium tuberculosis Isolates from Pulmonary Tuberculosis Patients in Colombia

Science.gov (United States)

Realpe, Teresa; Correa, Nidia; Rozo, Juan Carlos; Ferro, Beatriz Elena; Gomez, Verónica; Zapata, Elsa; Ribon, Wellman; Puerto, Gloria; Castro, Claudia; Nieto, Luisa María; Diaz, Maria Lilia; Rivera, Oriana; Couvin, David; Rastogi, Nalin; Arbelaez, Maria Patricia; Robledo, Jaime

2014-01-01

Background Phylogeographic composition of M. tuberculosis populations reveals associations between lineages and human populations that might have implications for the development of strategies to control the disease. In Latin America, lineage 4 or the Euro-American, is predominant with considerable variations among and within countries. In Colombia, although few studies from specific localities have revealed differences in M. tuberculosis populations, there are still areas of the country where this information is lacking, as is a comparison of Colombian isolates with those from the rest of the world. Principal Findings A total of 414 M. tuberculosis isolates from adult pulmonary tuberculosis cases from three Colombian states were studied. Isolates were genotyped using IS6110-restriction fragment length polymorphism (RFLP), spoligotyping, and 24-locus Mycobacterial interspersed repetitive units variable number tandem repeats (MIRU-VNTRs). SIT42 (LAM9) and SIT62 (H1) represented 53.3% of isolates, followed by 8.21% SIT50 (H3), 5.07% SIT53 (T1), and 3.14% SIT727 (H1). Composite spoligotyping and 24-locus MIRU- VNTR minimum spanning tree analysis suggest a recent expansion of SIT42 and SIT62 evolved originally from SIT53 (T1). The proportion of Haarlem sublineage (44.3%) was significantly higher than that in neighboring countries. Associations were found between M. tuberculosis MDR and SIT45 (H1), as well as HIV-positive serology with SIT727 (H1) and SIT53 (T1). Conclusions This study showed the population structure of M. tuberculosis in several regions from Colombia with a dominance of the LAM and Haarlem sublineages, particularly in two major urban settings (Medellín and Cali). Dominant spoligotypes were LAM9 (SIT 42) and Haarlem (SIT62). The proportion of the Haarlem sublineage was higher in Colombia compared to that in neighboring countries, suggesting particular conditions of co-evolution with the corresponding human population that favor the success of this

[Investigation of in vitro metronidazole resistance in the clinical isolates of Trichomonas vaginalis].

Science.gov (United States)

Ertabaklar, Hatice; Yaman Karadam, Senem; Malatyalı, Erdoğan; Ertuğ, Sema

2016-10-01

Trichomonas vaginalis, a flagellated, urogenital anaerobic protozoon is reported as an important cause of vaginitis with a global distribution. Although metronidazole is the primary choice of drug for the treatment of trichomoniasis, the presence of resistant isolates from many different countries highlights the need of novel drugs for the treatment. Many studies from Turkey mostly dealing with the in vitro effects of compounds and natural products against T.vaginalis have been reported, however, only one study has been encountered searching the metronidazole resistance in a single T.vaginalis isolate. The aim of this study was to determine the in vitro metronidazole resistance and minimum lethal concentrations (MLCs) of the isolates from symptomatic cases. T.vaginalis strains isolated from vaginal discharge samples of symptomatic women that were sent to Adnan Menderes University Faculty of Medicine, Research and Training Hospital Parasitology Laboratory, between 2009-2014 period, were included in the study. The strains were isolated by the inoculation of samples into trypticase-yeast-maltose medium supplemented with 10% fetal calf serum. A total of 40 T.vaginalis isolates stored by cryopreservation were revived before the experiments. T.vaginalis trophozoites were incubated with different concentrations of metronidazole (200, 100, 50, 25, 12.5, 6.25, 3.12, 1.56 μg/ml) and the viability of cells were examined in both aerobic and anaerobic conditions under phase contrast microscope. Additionally, non-motile isolates were further inoculated into fresh media and viability was checked. The wells containing motile trophozoites after 48 hours of incubation with 15 µg/ml and/or higher metronidazole concentration in anaerobic condition and 75 µg/ml and/or higher metronidazole concentration in aerobic conditions were determined as resistant isolates. Of the 40 T.vaginalis isolates three (7.5%) were resistant to metronidazole. MLC mean values of metronidazole

Genetic Variation of Giardia lamblia Isolates from Food-handlers in Kashan, Central Iran

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Hossein HOOSHYAR

2017-02-01

Full Text Available Background: Based on genotyping study of human isolates of Giardia lamblia; humans are mainly infected by two assemblages A and B. The present study was carried out to determine the sub-assemblages of G. lamblia isolated from food handlers referred to Kashan health centers, central Iran, 2015.Methods: In this cross-sectional study, 3653 stool samples collected from food-handlers that annually refer to health center for getting a health certification and examined microscopically for G. lamblia cyst. Totally, 44 isolates were selected from 47 Giardia positive samples. Cysts were partially purified by the sucrose density gradient method. After freeze-thaw cycles, genomic DNA was extracted using QIAamp Stool Mini kit. A single step PCR-RFLP method was used to amplify a 458bp fragment at the glutamate dehydrogenase (gdh locus, restriction enzymes BspLI and RsaI were used for distinguish between genotypes A and B and their subgroups.Results: Of 44 isolates, 24(54.5% were sub-assemblage AII, 9(20.5% group B including 7(15.9% BIII and 2(4.6% BIV sub-assemblage and 11(25% isolates showed a mixed pattern of AII and B. Sub-assemblage AI was not detected in this study.Conclusion: The higher rate of sub-assemblage AII demonstrated an anthroponotic origin of the infection so infected food-handlers could directly transmit this protozoan to consumers via contaminated food and water. For finding of pattern of transmission and distribution of Giardia assemblages and sub-assemblage, more studies in human and animal population in different regions are necessary.

Salmonella Strains Isolated from Galápagos Iguanas Show Spatial Structuring of Serovar and Genomic Diversity

Science.gov (United States)

Lankau, Emily W.; Cruz Bedon, Lenin; Mackie, Roderick I.

2012-01-01

It is thought that dispersal limitation primarily structures host-associated bacterial populations because host distributions inherently limit transmission opportunities. However, enteric bacteria may disperse great distances during food-borne outbreaks. It is unclear if such rapid long-distance dispersal events happen regularly in natural systems or if these events represent an anthropogenic exception. We characterized Salmonella enterica isolates from the feces of free-living Galápagos land and marine iguanas from five sites on four islands using serotyping and genomic fingerprinting. Each site hosted unique and nearly exclusive serovar assemblages. Genomic fingerprint analysis offered a more complex model of S. enterica biogeography, with evidence of both unique strain pools and of spatial population structuring along a geographic gradient. These findings suggest that even relatively generalist enteric bacteria may be strongly dispersal limited in a natural system with strong barriers, such as oceanic divides. Yet, these differing results seen on two typing methods also suggests that genomic variation is less dispersal limited, allowing for different ecological processes to shape biogeographical patterns of the core and flexible portions of this bacterial species' genome. PMID:22615968

Salmonella strains isolated from Galápagos iguanas show spatial structuring of serovar and genomic diversity.

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Emily W Lankau

Full Text Available It is thought that dispersal limitation primarily structures host-associated bacterial populations because host distributions inherently limit transmission opportunities. However, enteric bacteria may disperse great distances during food-borne outbreaks. It is unclear if such rapid long-distance dispersal events happen regularly in natural systems or if these events represent an anthropogenic exception. We characterized Salmonella enterica isolates from the feces of free-living Galápagos land and marine iguanas from five sites on four islands using serotyping and genomic fingerprinting. Each site hosted unique and nearly exclusive serovar assemblages. Genomic fingerprint analysis offered a more complex model of S. enterica biogeography, with evidence of both unique strain pools and of spatial population structuring along a geographic gradient. These findings suggest that even relatively generalist enteric bacteria may be strongly dispersal limited in a natural system with strong barriers, such as oceanic divides. Yet, these differing results seen on two typing methods also suggests that genomic variation is less dispersal limited, allowing for different ecological processes to shape biogeographical patterns of the core and flexible portions of this bacterial species' genome.

Molecular characterization of two isolates of sweet potato leaf curl ...

African Journals Online (AJOL)

Comparison analysis showed that DNA-A sequence of JS1 isolate was closely related to that of sweet potato leaf curl virus (SPLCV) from United States with nucleotide sequence identity of 97.0% and DNA-A of Y338 showed highest sequence identity at 97.8% with an isolate of SPLCV from China. Phylogenetic analysis ...

Isolation of Campylobacter from Brazilian broiler flocks using different culturing procedures.

Science.gov (United States)

Vaz, C S L; Voss-Rech, D; Pozza, J S; Coldebella, A; Silva, V S

2014-11-01

Conventional culturing methods enable the detection of Campylobacter in broiler flocks. However, laboratory culture of Campylobacter is laborious because of its fastidious behavior and the presence of competing nontarget bacteria. This study evaluated different protocols to isolate Campylobacter from broiler litter, feces, and cloacal and drag swabs. Samples taken from commercial Brazilian broiler flocks were directly streaked onto Preston agar (PA), Campy-Line agar (CLA), and modified charcoal cefoperazone deoxycholate agar (mCCDA) and also enriched in blood-free Bolton broth (bfBB) for 24 and 48 h followed by plating onto the different selective media. Higher numbers of Campylobacter-positive cloacal and drag swab samples were observed using either direct plating or enrichment for 24 h before plating onto PA, compared with enrichment for 48 h (P media. Together, these data showed that direct plating onto PA and onto either CLA or mCCDA as the second selective agar enabled the reliable isolation of thermophilic Campylobacter species from broiler samples. Finally, Campylobacter was detected in all broiler flocks sampled. ©2014 Poultry Science Association Inc.

The complete nucleotide sequence of the barley yellow dwarf GPV isolate from China shows that it is a new member of the genus Polerovirus.

Science.gov (United States)

Zhang, Wenwei; Cheng, Zhuomin; Xu, Lei; Wu, Maosen; Waterhouse, Peter; Zhou, Guanghe; Li, Shifang

2009-01-01

The complete nucleotide sequence of the ssRNA genome of a Chinese GPV isolate of barley yellow dwarf virus (BYDV) was determined. It comprised 5673 nucleotides, and the deduced genome organization resembled that of members of the genus Polerovirus. It was most closely related to cereal yellow dwarf virus-RPV (77% nt identity over the entire genome; coat protein amino acid identity 79%). The GPV isolate also differs in vector specificity from other BYDV strains. Biological properties, phylogenetic analyses and detailed sequence comparisons suggest that GPV should be considered a member of a new species within the genus, and the name Wheat yellow dwarf virus-GPV is proposed.

Comparison of protocols and RNA carriers for plasma miRNA isolation. Unraveling RNA carrier influence on miRNA isolation

Science.gov (United States)

Martos, Laura; Fernández-Pardo, Álvaro; Oto, Julia; Medina, Pilar; España, Francisco; Navarro, Silvia

2017-01-01

microRNAs are promising biomarkers in biological fluids in several diseases. Different plasma RNA isolation protocols and carriers are available, but their efficiencies have been scarcely compared. Plasma microRNAs were isolated using a phenol and column-based procedure and a column-based procedure, in the presence or absence of two RNA carriers (yeast RNA and MS2 RNA). We evaluated the presence of PCR inhibitors and the relative abundance of certain microRNAs by qRT-PCR. Furthermore, we analyzed the association between different isolation protocols, the relative abundance of the miRNAs in the sample, the GC content and the free energy of microRNAs. In all microRNAs analyzed, the addition of yeast RNA as a carrier in the different isolation protocols used gave lower raw Cq values, indicating higher microRNA recovery. Moreover, this increase in microRNAs recovery was dependent on their own relative abundance in the sample, their GC content and the free-energy of their own most stable secondary structure. Furthermore, the normalization of microRNA levels by an endogenous microRNA is more reliable than the normalization by plasma volume, as it reduced the difference in microRNA fold abundance between the different isolation protocols evaluated. Our thorough study indicates that a standardization of pre- and analytical conditions is necessary to obtain reproducible inter-laboratory results in plasma microRNA studies. PMID:29077772

Pebble-isolation mass: Scaling law and implications for the formation of super-Earths and gas giants

Science.gov (United States)

Bitsch, Bertram; Morbidelli, Alessandro; Johansen, Anders; Lega, Elena; Lambrechts, Michiel; Crida, Aurélien

2018-04-01

The growth of a planetary core by pebble accretion stops at the so-called pebble isolation mass, when the core generates a pressure bump that traps drifting pebbles outside its orbit. The value of the pebble isolation mass is crucial in determining the final planet mass. If the isolation mass is very low, gas accretion is protracted and the planet remains at a few Earth masses with a mainly solid composition. For higher values of the pebble isolation mass, the planet might be able to accrete gas from the protoplanetary disc and grow into a gas giant. Previous works have determined a scaling of the pebble isolation mass with cube of the disc aspect ratio. Here, we expand on previous measurements and explore the dependency of the pebble isolation mass on all relevant parameters of the protoplanetary disc. We use 3D hydrodynamical simulations to measure the pebble isolation mass and derive a simple scaling law that captures the dependence on the local disc structure and the turbulent viscosity parameter α. We find that small pebbles, coupled to the gas, with Stokes number τf gap at pebble isolation mass. However, as the planetary mass increases, particles must be decreasingly smaller to penetrate the pressure bump. Turbulent diffusion of particles, however, can lead to an increase of the pebble isolation mass by a factor of two, depending on the strength of the background viscosity and on the pebble size. We finally explore the implications of the new scaling law of the pebble isolation mass on the formation of planetary systems by numerically integrating the growth and migration pathways of planets in evolving protoplanetary discs. Compared to models neglecting the dependence of the pebble isolation mass on the α-viscosity, our models including this effect result in higher core masses for giant planets. These higher core masses are more similar to the core masses of the giant planets in the solar system.

Isolation and identification of crude oil degrading bacteria from gastropod Haustrum scobina collected from Persian Gulf (Bandar Abbas Shoreline provenance

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Zinab Bayat

2016-06-01

Full Text Available Introduction: Biodegradation is a good alternative rather than chemical and physical methods for cleaning oil contaminated areas. Several factors like crude oil concentration, biosurfactant production, salinity and incubation time affect the biodegradation. Materials and methods: In this study, seawater sample and gastropod were collected from Persian Gulf. To isolate oil degrading bacteria from collected samples, ONR7a medium was used. The strains that had more growth and higher oil removal were selected and identified. The factors such as the effect of different concentrations of oil, incubation time, mixed cultures and salinity on the biodegradation were investigated. Results: Six crude oil degrading bacteria were isolated. Between these bacteria 2 strains were selected based on higher oil removal. These strains belonged to the genus Vibrio and Halomonas. Strains with higher Emulsification activity produce more biosurfactant and have higher oil biodegradation. Growth and oil degradation have increment pattern by prolonging the incubation time. Mixed culture of Vibrio and Halomonas strains have higher rates of degradation rather than culturing with one of them. Increase in crudeoil concentration to 2.5% caused reduction in growth of bacteria and degradation of oil. Discussion and conclusion: The results of this study show that crude oil degrading bacteria have high diversity in Persian Gulf. These bacteria have higher capability for oil degradation thus they can be used for remediation of oil contaminated areas.

Genetic diversity of Enterococcus faecalis isolated from environmental, animal and clinical sources in Malaysia

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Diane S. Daniel

2017-09-01

Full Text Available Enterococcus faecalis ranks as one of the leading causes of nosocomial infections. A strong epidemiological link has been reported between E. faecalis inhabiting animals and environmental sources. This study investigates the genetic diversity, antibiotic resistance and virulence determinants in E. faecalis from three sources in Malaysia. A total of 250 E. faecalis isolates were obtained consisting of 120 isolates from farm animals, 100 isolates from water sources and 30 isolates from hospitalized patients. Pulse-field gel electrophoresis-typing yielded 63 pulsotypes, with high diversity observed in all sources (D = ≥0.901. No pulsotype was common to all the three sources. Each patient room had its own unique PFGE pattern which persisted after six months. Minimum inhibitory concentrations of Vancomycin, Gentamicin, Penicillin, Tetracycline, Nitrofurantoin, Levofloxacin, Ciprofloxacin and Fosfomycin were evaluated. Resistance to Tetracycline was most prevalent in isolates from farm animals (62% and water sources (49%. Water isolates (86% had a higher prevalence of the asa1 gene, which encodes for aggregation substance, whereas clinical (78% and farm animal isolates (87% had a higher prevalence of the esp gene, encoding a surface exposed protein. This study generates knowledge on the genetic diversity of E. faecalis with antibiotic resistance and virulence characteristics from various sources in Malaysia. Keywords: Antibiotic resistance, Enterococcus faecalis, Genetic diversity, Molecular typing, Virulence markers

Comparative study of Microsporum canis isolates by DNA fingerprinting.

Science.gov (United States)

Shafiee, Shabnam; Khosravi, Ali Reza; Ashrafi Tamai, Iradj

2014-08-01

Microsporum canis is a zoophilic fungus and it is an important agent of dermatophytosis. Cats act as important reservoirs. Clinically, it is too difficult to differentiate dermatophytosis caused by various species, also this fungus loses its morphological characteristics easily because of subculture; so using of rapid and accurate laboratory techniques for identifying the dermatophytes is important, therefore, RAPD-PCR was applied for the differentiation of the isolates. In this study, 10 M. canis isolates were detected in cats, dog, human, fox and rabbit at the Mycology Research Center, Faculty of Veterinary Medicine, University of Tehran. For running the RAPD-PCR, PCR set system and three random primers OPU 15, OPU 13 and OPA 04 were used. Then phylogenetic tree and similarity coefficient table were drawn. The results showed that there were some common bands between M. canis isolates. There were some specific bands for each isolates, as well. Our study showed, despite the typical morphology of the whole isolates, they were placed in different branches in molecular typing. © 2014 Blackwell Verlag GmbH.

Detection of phospholipase activity of Candida albicans and non albicans isolated from women of reproductive age with vulvovaginal candidiasis in rural area

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S R Fule

2015-01-01

Full Text Available Background: Vulvovaginal candidiasis (VVC is most common accounting for 17 to 39% of symptomatic women. Both Candida albicans and non albicans Candida species are involved in VVC. Amongst various virulence factors proposed for Candida, extracellular phospholipases is one of the virulence factor implicated in its pathogenicity. With this background the present study was carried out to find the prevalence of different Candida species and to detect phospholipase producing strains isolated from symptomatic women with VVC. Materials and Methods: At least two vaginal swabs from 156 women of reproductive age with abnormal vaginal discharge were collected. Direct microscopy and Gram′s stained smear examined for presence of budding yeast and pseudo mycelia followed by isolation and identification of Candida species. Extracellular phospholipase activity was studied by inoculating all isolates on Sabouraud′s dextrose egg yolk agar (SDA medium. Results: Of the 156 women with curdy white discharge alone or in combination with other signs, 59 (37.82% women showed laboratory evidence of VVC. A total of 31 (52.54% women had curdy white discharge followed by 12 (20.33% with other signs and symptoms. C. albicans (62.59% and non albicans Candida (37.28% in a ratio of 1.68:1 were isolated. Of the 37 strains of C. albians 30 (81.08% showed the enzyme activity. Seventeen (56.66% strains showed higher Pz value of < 0.70 (++++. Conclusion: Although there may be typical clinical presentation of Candidiasis. all the patients did not show laboratory evidence of infection. Pregnancy was found to be major risk factor for development of VVC. C. albicans was prevalent species but non albicans species were also frequently isolated. Extracellular phospholipase activity was seen in C. albicans and not in non albicans Candida isolates.