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Different Microorganisms (different + microorganism)

Distribution by Scientific Domains

Medical Sciences	40%
Life Sciences	40%

Selected Abstracts

Real-time PCR with internal amplification control for detecting tuberculosis: method design and validation

APMIS, Issue 8 2009
E. FLORES
Flores E, Rodríguez JC, Garcia-Pachón E, Soto JL, Ruiz M, Escribano I, Royo G. Real-time PCR with internal amplification control for detecting tuberculosis: method design and validation. APMIS 2009; 117: 592,7. Real-time PCR has been a major development in the diagnosis of tuberculosis. However, most tests do not include an internal amplification control (IAC), which therefore limits it clinical application. In this study a new, easy to perform real-time PCR test with IAC was designed and validated in clinical samples. The primers amplified a 163-bp fragment of IS6110 of Mycobacterium tuberculosis and the IAC was designed with a fragment of a different microorganism (Chlamydia trachomatis). The interassay and intraassay variation of this test were very low (0.45,1.65% and 0.18,1.80%, respectively). The detection accuracy was validated in 50 samples (25 urine, 25 sputum) with different concentrations of M. tuberculosis, 18 clinical isolates of non-tuberculous mycobacteria and 148 samples with clinical suspicion of pulmonary tuberculosis. The specificity was 100%. The detection limit of this PCR test without IAC was approximately 15 bacteria and with IAC approximately 32 bacteria. This real-time PCR with IAC assay can improve the detection of M. tuberculosis and contribute to standardization of this diagnostic technique. [source]

Lipid biomarkers, pigments and cyanobacterial diversity of microbial mats across intertidal flats of the arid coast of the Arabian Gulf (Abu Dhabi, UAE)

FEMS MICROBIOLOGY ECOLOGY, Issue 3 2008
Raeid M.M. Abed
Abstract Variations in morphology, fatty acids, pigments and cyanobacterial community composition were studied in microbial mats across intertidal flats of the arid Arabian Gulf coast. These mats experience combined extreme conditions of salinity, temperature, UV radiation and desiccation depending on their tidal position. Different mat forms were observed depending on the topology of the coast and location. The mats contained 63 fatty acids in different proportions. The increased amounts of unsaturated fatty acids (12,39%) and the trans/cis ratio (0.6,1.6%) of the cyanobacterial fatty acid n- 18:1,9 in the higher tidal mats suggested an adaptation of the mat microorganisms to environmental stress. Chlorophyll a concentrations suggested lower cyanobacterial abundance in the higher than in the lower intertidal mats. Scytonemin concentrations were dependent on the increase in solar irradiation, salinity and desiccation. The mats showed richness in cyanobacterial species, with Microcoleus chthonoplastes and Lyngbya aestuarii morphotypes as the dominant cyanobacteria. Denaturing gradient gel electrophoresis patterns suggested shifts in the cyanobacterial community dependent on drainage efficiency and salinity from lower to higher tidal zones. We conclude that the topology of the coast and the variable extreme environmental conditions across the tidal flat determine the distribution of microbial mats as well as the presence or absence of different microorganisms. [source]

Spectroscopic Differentiation and Quantification of Microorganisms in Apple Juice

JOURNAL OF FOOD SCIENCE, Issue 7 2004
Chenxu Yu
ABSTRACT: A fast and easy-to-operate Fourier Transform Infrared (FTIR) spectrometry-based approach was developed for microbial differentiation and quantification in apple juice. Eight different microorganisms were evaluated: Enterobacter cloacae, Salmonella typhimurium, Enterobacteraerogenes, Salmonella choleraesuis, Serratia marcescens, Pseudomonas vulgaris, Vibrio cholerae, and Hafnia alvei. FTIR spectroscopy combined with chemometrics could differentiate the microorganisms studied at low concentration level of 103 colony-forming units (CFU) /mL in apple juice. The chemometric models developed to count microorganisms in apple juice were validated by an independent test set consisting of 18 samples and correlated against plate counts satisfactorily up to a detection limit of 103 CFU/mL. [source]

The limit of leucocytospermia from the microbiological viewpoint

ANDROLOGIA, Issue 5 2003
Margus Punab
Summary. The aim of the study was to find out the correlation between white blood cell (WBC) counts in semen and quantitative composition of seminal microflora, and to establish the minimum WBC count associated with significant bacteriospermia. The research included 159 men with different WBC counts in their semen, 84 of them with chronic prostatitis/chronic pelvic pain syndrome. Semen samples were cultivated quantitatively for detecting anaerobic, microaerophilic and aerobic bacteria. Bryan-Leishman stained slides were used for detecting WBC in semen. Seminal fluid was colonized by eight different microorganisms, and the total count of microorganisms in semen ranged from 102 to 107 CFU ml,1. A high frequency of anaerobic microorganisms was found. A positive correlation was observed between the WBC count and the number of different microorganisms, and also between the WBC count and the total count of microorganisms in semen sample. The receiver operating characteristic curve analysis demonstrated that the WHO-defined WBC cut-off point (1 × 106 WBC ml,1) has very low sensitivity for discriminating between patients with and without significant bacteriospermia, as a more optimal sensitivity/specificity ratio appears at 0.2 × 106 WBC ml,1 of semen. The quantitative microbiological finding of semen in the patients of National Institute of Health (NIH) categories IIIa and IV was very similar, i.e. a high number of different microorganisms and a high total count of microorganisms. In the control group (without leucocytospermia and prostatitis symptoms) both parameters were significantly lower. [source]

Insect immunity and its implication in mosquito,malaria interactions

CELLULAR MICROBIOLOGY, Issue 1 2003
George Dimopoulos
Summary Insects' resistance to infectious agents is essential for their own survival and also for the health of the plant, animal and human populations with which they closely interact. Several of the major human diseases are spread by insects and are rapidly expanding as a result of the development of insecticide resistance in vectors and drug resistance in parasites. A vector insects' permissiveness to a pathogen, and hence the spread of the disease, will largely depend on the compatibility of the molecular interactions between the two species and the capability of the insect immune system to recognize and kill the pathogen. The innate immune system comprises a variety of components and mechanisms that can discriminate between different microorganisms and mount specific responses to control pathogenic infections. An impressive body of knowledge on the insects' innate immunity has been generated from studies in the model organism Drosophila. These studies are now guiding the exploration of the immune system in the vector mosquito of human malaria, Anopheles, and its implication in the elimination of parasites. Anopheles immune responses have been linked to parasite losses and some refractory mosquitoes can kill all parasites through specific defence mechanisms. The recently sequenced Drosophila and Anopheles genomes provide a detailed and comparative view on their immune gene repertoires that in combination with post-genomic analyses is used to further dissect the complex mechanisms of Plasmodium killing in the mosquito. [source]