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文章
Chen-Xiaoxi and Chen-Weiliang
Abstract: With a view to exploring whether there was a correlation between a novel antibiotic and a plasmid, the plasmid was eliminated by SDS. Because the elimination of the plasmid had no effect on the bacterium’s producing antibiotic, it was determined that the plasmid had nothing to do with the antibiotic. However, with the plasmid being eliminated, the ability of the bacterium to secrete a kind of adhesive substance was lost, and the phenotype of the bacterium was also changed. This indicated that the plasmid was closely related to this adhesive substance and that the adhesive substance determined the bacterium’s phenotype. In addition, losing the plasmid meant losing life if the bacterium was under adverse circumstances like cold condition. It meant that the function of the plasmid (or the adhensive substance) was to protect the bacterium.[...] Read More.
Keywords: Plasmid, phenotype, antibiotic, viability, bacterium.
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Dilek Satana*, Gonca Erkose Genc and Zayre Erturan
Abstract: Oropharyngeal candidiasis (OPC) is the most common HIV related oral lesion. Most patients are infected with a strain originally present as a commensal of the oral cavity. The resistance of Candida isolates to antifungal drugs is important due to morbidity and mortality. The aim of our study was to investigate the antifungal susceptibility profiles of oral Candida spp which were isolated from HIV-infected patients. In vitro susceptibility tests were performed using the broth microdilution method recommended by the Clinical and Laboratory Standard Institute (CLSI). A total of 67 oral Candida isolates from colonized HIV-infected patients, which were previously isolated and identified were included in this study. MIC ranges were 0.12 - 4.0, 0.12 - 16, 0.03 - 1.0, 0.03 - 1.0, and 0.03 - 0.25 µg/ml for amphotericin B, fluconazole, itraconazole, ketoconazole and voriconazole, respectively. All isolates were fully susceptible to voriconazole. Sixty five (97%) of all isolates were determined fully susceptible to amphotericin B, 66 (98.5%) to fluconazole, 64 (95.5%) to ketoconazole and 50 (88%) to itraconazole. No resistance was detected to fluconazole and voriconazole in oral Candida strains isolated from colonized Turkish HIV positive patients. Antifungal resistance was detected in 8.96% (6 strains) of all isolates tested.[...] Read More.
Keywords: HIV, Candida, oropharyngeal carriage, antifungal agents, antifungal susceptibility.
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Clara Prats*, Jordi Ferrer, Daniel López, Antoni Giró and Josep Vives-Rego
Abstract: Individual-based modelling (IbM) has become a fully incorporated part of predictive microbiology methodologies in the last decade. Previous studies of bacterial culture growth cycle with the IbM simulator INDISIM analysed the evolution of bacterial biomass distribution during the different phases of growth. The predicted forward shift during lag, stability during exponential and backward shift when entering the stationary phase have been experimentally observed in an Escherichia coli batch culture by means of flow cytometry and particle size analysis measurements. In addition, the experimental results were analysed using the product distance, a mathematical tool developed to assess the evolution of cell size distribution. These results confirmed the assumptions about the bacterial lag phase made by INDISIM. Moreover, flow cytometry and particle analysis methods were shown to be useful experimental techniques in combination with IbM simulations when studying the evolution of individual properties during the bacterial growth cycle. This is essential in order to provide a new and consistent interpretation of the dynamics and heterogeneity of cell biomass during the growth cycle.[...] Read More.
Keywords: Bacterial cell cycle phases, biomass distribution, individual-based modelling, flow cytometry, particle size analysis.
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G. Aydemir*, C. Meral, S. Suleymanoglu , F. Karademir and Tarık engör
Abstract: To determine the bacterial etiology of acute middle ear infections in preschool age children. This prospective descriptive clinical study was implemented in Marmaris town between November, 2008 and May, 2009 with 80 cases. Their age ranged from 2 - 6. One fourth of the cases were preschoolers. The diagnosis of acute middle ear infection was confirmed by an otolaryngologist following a pediatrician and paracentesis that was performed. Bacterial culture was done in regular conditions and antibacterial resistance was assessed with disk diffusion method. Streptococcus pneumoniae was the most frequent etiologic agent. It was followed by Haemophilus influenzae (15%) and Staphylococcus aureus (6%) in order of frequency. The penicillin resistance rate of pneumococci was 24%.[...] Read More.
Keywords: Child, infection, middle ear infection.
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O. ’Lanre Olaitan*, O. O. Oyerinde, O. Obiyemi and O. O Kayode
Abstract: The study determined the job stress among primary school teachers in South-west, Nigeria. A total of 624 teachers were chosen as subjects using a multistage sampling technique, and a structure questionnaire was used to gather information from the subjects. Research hypotheses were formulated and inferential statistics of test and analysis of variance ANOVA were employed to analyze significant differences at a = 0.05 level. The differences were significant only for age and gender. Majority of the teachers have headache as symptom of poor health and majority of them engage in watching TV as a strategy for coping with stress. The major source of stress for the subjects is the society. It was recommended among others that, teachers working condition should be improved by planning educational ergonomics and of some social facilities such as: satellite TV; computer connected with Internet; and that the school curriculum should take into cognizance, sporting activities especially for the teachers which should be given a bit of knowledge in health education so to be able to understand themselves and generate more coping techniques for job stress.[...] Read More.
Keywords: Job, stress, ergonomics.
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Pongsak Rattanachaikunsopon* and Parichat Phumkhachorn
Abstract: Carvacrol, a major compound naturally present in oregano and thyme and its precursor, cymene, were tested in vitro for their antimicrobial activity against Edwardsiella tarda, a fish pathogenic bacteria causing edwardsiellosis. When used alone, carvacrol, but not cymene, inhibited the bacterium with the minimal inhibitory concentration (MIC) of 20 ppm. However, cymene was shown to be able to enhance the inhibitory ability of carvacol indicated by the reduction of MIC to 5 ppm when used with 2.5 ppm of cymene. Based on mortalities in 2 weeks after intraperitoneal E. tarda injection, the median lethal dose (LD50) of E. tarda for tilapia (Oreochromis niloticus) was 5.0 × 102 CFU/g of fish. Fish diets supplemented with carvacrol and cymene were also tested for their protective effect against E. tarda infection in tilapia. The results showed that carvacrol (200 ppm) but not cymene (200 ppm) when fed prophylactically decreased the mortality in E. tarda-challenged tilapia. However, carvacrol at the same concentration could cause no mortality of E. tarda infected fish when used in conjunction with 200 ppm of cymene.[...] Read More.
Keywords: Carvacrol, cymene, Edwardsiella tarda, tilapia.
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Selvakumar Dharmaraj*, B. Ashokkumar and K. Dhevendaran
Abstract: Nearly ten isolates of Streptomyces were found to be associated with two species of sponges namely Mycale mytilorum (Annandale) and Tendania anhelans (Lieberkuhn). Among the ten isolates, four strains of white series were selected and characterized by conventional methods and assessed for their antagonistic activity against fish pathogens like Aeromonas hydrophila and Vibrio sp. All the strains showed inhibitory activity against these fish pathogens. The screening of antibacterial substances by the Streptomyces isolates proved the production of highly polyene nature compounds which were observed using criteria like thin layer chromatography (TLC) and spectral analysis. The results of the present investigation revealed that the sponges associated Streptomyces were found to be promising source of antibacterial bioactive substances. It concludes that development of appropriate fermentation and downstream processing technologies would bring out new classes of antibiotic leads.[...] Read More.
Keywords: Antimicrobials, marine Streptomyces, marine sponges.
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Maurice S. Mikhail, Kamel K. Sabet, Moawad R. Omar, Amal A. Asran and Khaled K. Kasem,*
Abstract: Twenty eight isolates of Rhizoctonia solani were obtained from cotton seedlings and twenty three isolates from other hosts; eight from peanut, five from chickpea, two from each of flax, tomato and watermelon and one from each of potato, cantaloupe, pepper and lupine. Microscopic examination revealed that 17 isolates (33.33%) each belonged to AG-2- 2, 17 and AG-4 HG-I, while 7 isolates (13.73%) belonged to AG -4 HG-II and 10 isolates (19.61%) belonged to AG-5. Pathogenicity test on cotton cultivar Giza 86, under greenhouse conditions, showed that 19 isolates significantly induced pre- and post-emergence damping-off, while they significantly decreased survival, plant height and dry weight. However, the pathogenic isolates of AG-2-2 represented 19.61% of the total isolates as well as the highest percentage of the pathogenic isolates (52.63%). There were no significant differences between effects of different AGs on the cotton seedling variables. Cluster analysis suggested that grouping the isolates based on their virulence patterns was not related to their geographic origins, AG or host.[...] Read More.
Keywords: Rhizoctonia solani, anastomosis groups, cotton, pathogenicity.
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Elmira Gheytanchi, Fariba Heshmati, Bahareh Kordestani Shargh, Jamileh Nowroozi and
Abstract: -galactosidases enzyme have been used in the dairy industry for the improvement of lactose intolerance. The aim of this study was to detect b-galactosidase enzyme produced by isolated lactobacilli from milk and cheese. Isolated lactobacilli were cultured on MRS agar. Lactobacilli were identified by Gram stain and standard bacteriological and biochemical methods. Their ability to hydrolyze 5-bromo-4-chloro-3-indolyl- -D- galactopyranoside (X-Gal) and O-nitrophenyl- -D-galactopyranoside (ONPG) was determined. A protein band of indicated b-galactosidase enzyme was also detected by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) method. The colonies that produced green color on X-Gal plates were lactobacilli with b-galactosidase enzyme which had ONPG positive results. The highest enzymatic value (1,966 U/ml) was observed in one strain of Lactobacillus delbrueckii. A 116 kDa protein band was detected in some strains (37%) with highest enzyme value and in others (63%), protein band was weak by SDS-PAGE method. By adding Lactobacilli producing b-galactosidase enzyme as probiotic to dairy products, could help lactose intolerant people.[...] Read More.
Keywords: Lactobacillus,  -galactosidase, X-Gal, ONPG, SDS-PAGE.
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文章
 I. A. Adeoye, M. D. Dairo, L. V. Adekunle, H. O. Adedokun and J. Makanjuola
Abstract: The global burden of measles has remained a public health challenge. Worldwide, measles is the fifth leading cause of death among under-five children with an estimate of 197,000 deaths in 2007. In Nigeria, measles is an important cause of childhood morbidity and mortality. Measles outbreaks have been increasingly common in the country with 30, 194 and 256 outbreaks reported in 2006, 2007 and 2008 respectively. This paper describes the investigation, findings and mitigation efforts of a measles outbreak in Ogunmakin, a rural community in South-western Nigeria from 7th January to 15 th February 2009. The study design was descriptive and cross-sectional in nature. The investigation was multi-disciplinary in nature performed based on the national guidelines for investigating a measles outbreak. This involved data and blood sample collection from the initial cases, notification of the local government health authority, active search and line listing of cases from other health facilities. A household survey was conducted to find additional cases as well as to define the extent of the outbreak. Qualitative techniques were also employed to explore the issues associated with the uptake of immunization in the community. A total of 29 measles cases were identified, all were less than five years old. There were two deaths giving a case fatality rate of 6.9%. Majority of the cases (96.5%) were not immunized against measles. The epidemic spanned 5 weeks with majority of the cases occurring in the 2nd week. There was a clustering of cases in one of the five quarters/settlement – Otesile. The measles immunization coverage for the community was estimated as 22.9%. The stated reasons for the poor uptake of immunization were lack of time, not regarding it as important. A total of 432 children aged 9 months to 15 years received measles antigen during the response vaccination campaign. The measles outbreak in Ogunmakin village was due to low routine immunization coverage resulting in an accumulation of susceptible children. Socio-cultural factors and weak health infrastructure contribute significantly to the low uptake of immunization. There is the need mobilized the entire community on the importance of immunization as well as strengthen the provision of routine immunization.[...] Read More.
Keywords: Measles, public health, immunization, childhood morbidity, childhood mortality, vaccination.
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