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At least 145 records · Page 8Linked to original sources
PubMed1986

Preoperative irradiation potentiation with cisplatin: effect on rate of wound infection.

Platinum coordination complexes, such as cisplatin, potentiate the cytotoxicity of irradiation on squamous cell carcinoma and certain other solid tumors. Using a rat oro-cutaneous fistula model, an investigation was carried out to determine whether or not there was a concomitant potentiation with cisplatin of the deleterious effect of preoperative irradiation on the ability of a subsequent wound to handle a bacterial challenge. Auto-contaminated wounds were found to have increased rates of infection at single-dose orthovoltage pretreatments of 1,500 rads or more. Using quantitative bacteriologic techniques, would infection was found to be no more frequent after platinum-enhanced irradiation than after irradiation alone; however, there was the additive effect of weight loss associated with combined cisplatin treatment and irradiation.

Animals↗
PubMed1989

Local anti-P32 humoral response in tuberculous meningitis.

We report five cases of severe pulmonary tuberculosis admitted to hospital with a suspicion of meningeal involvement. The diagnosis of tuberculous meningitis was confirmed by standard bacteriological techniques in two of the five patients. Specific IgG class antibodies directed against the recently purified BCG antigen P32 were detected by a dot immunoblotting technique in the serum and in the cerebrospinal fluid of each patient; however, a higher anti-P32 immunoglobulins/total immunoglobulins ratio was observed in the cerebrospinal fluid of patients with tuberculous meningitis than in their serum while the reverse situation was observed in the other patients.

Adult↗
PubMed1996

Classification and identification of bacteria: current approaches to an old problem. Overview of methods used in bacterial systematics.

Most of the bacterial species are still unknown. Consequently, our knowledge about bacterial ecology is poor and expectations about specialized species with novel enzymatic functions or new products are high. Thus, bacterial identification is a growing field of interest within microbiology. In this review, suitability of developments for identification based on miniaturized biochemical and physiological investigations of bacteria are evaluated. Special emphasis is given to chemotaxonomic methods such as analysis of quinone system, fatty acid profiles, polar lipid patterns, polyamine patterns, whole cell sugars, peptidoglycan diaminoacids, as well as analytical fingerprinting methods and cellular protein patterning. 16S rDNA sequencing introduced to investigate the phylogenetic relationships of bacteria, nucleic acids hybridization techniques and G + C content determination are discussed as well as restriction fragment length polymorphism (RFLP), macrorestriction analysis and random amplified polymorphic DNA (RAPD). The importance of the different approaches in classification and identification of bacteria according to phylogenetic relationships are demonstrated on selected examples.

Bacteria↗
PubMed1992

Microbiology of postoperative wound infection: a prospective study of 1770 wounds.

A prospective study of postoperative wound infection was carried out over a 12-month period. Intra-operative swabs from the patients' anterior nares, the opened viscus and parietes were cultured using standard bacteriological techniques. Of the 1770 wounds studied, 167 (9.4%) became infected. Wound infection rates, according to clinical wound types, were clean 5.9%, clean-contaminated 10.7%, contaminated 24.3% and dirty 52.9%. The figures according to microbiological wound types were clean 4.7%, and potentially, lightly and heavily contaminated 15.3%, 22.1% and 30.2% respectively. The commonest causative organisms were Staphylococcus aureus 23.7%, Escherichia coli 16.9%, Staphylococcus epidermidis 13.5% and Pseudomonas aeruginosa 13.0%. When isolated intra-operatively, Enterobacter spp., Proteus spp., Klebsiella spp. and P. aeruginosa appeared to have a high probability of causing postoperative wound infection, but the intra-operative isolation of Bacteroides sp. was a poor predictor of subsequent wound infection.

Adolescent↗
PubMed1983

A report of an outbreak of Salmonella oranienburg in a hybrid mouse colony.

Mice in a hybrid breeding colony developed symptoms compatible with a diagnosis of salmonellosis. Salmonella oranienburg was recovered from feces by conventional bacteriological techniques. Active salmonellosis appeared to be precipitated by the stress of pregnancy among breeder female BALB/c mice. Necropsy examination of the BALB/c breeder females revealed diarrhea, roughened hair coats, enlarged spleens, white foci in the liver, and skin abscesses. S. oranienburg was recovered from the spleen, cecum, oropharynx, uterus, and skin abscesses of affected mice. DBA/2N breeder males were asymptomatic and S. oranienburg was recovered from the cecum only. Breeding productivity indices dropped to unacceptable levels in rooms containing infected animals. Relatively normal production was observed among uninfected animals of the same strains in adjacent rooms, thus demonstrating the detrimental effect S. oranienburg had on this breeder colony.

Animal Husbandry↗
PubMed2004

Optimal detection of Staphylococcus aureus from clinical specimens using a new chromogenic medium.

The new chromogenic medium CHROMagar Staph aureus (CASA) was evaluated for its ability to detect and presumptively identify Staphylococcus aureus. Nine hundred forty-two clinical specimens (742 wound, 200 sputum and bronchoalveolar lavage) were cultured on CASA, tryptic soy blood agar (TSBA), and mannitol salt agar (MSA). Of the 153 S. aureus isolates from wounds on any media, 151 grew on CASA and TSBA and 146 on MSA. Sensitivity after 24 hours was 93.5%, 94%, and 77%, respectively, and increased after 48 hours to 99% for CASA and TSBA and to 95% for MSA. Of the 41 isolates recovered from sputum and lavage, all grew on CASA, 27 on TSBA, and 36 on MSA. Sensitivity after 24 hours was 93%, 66%, and 81%, respectively, and 100%, 66%, and 88% after 48 hours. All specimens revealed 99% sensitivity for CASA, 92% for TSBA, and 94% for MSA. Specificity for CASA was 100%. Antimicrobial susceptibility tests showed full agreement between isolates from CASA and from reference media. In conclusion, CASA has a high sensitivity and can identify isolates undetected on conventional media (p value for CASA vs. TSBA was 0.001 and vs. MSA, 0.006). This difference is particularly notable when mixed flora are present. The simplicity of the colony recognition increased the medium specificity, allowing a reliable and rapid method for the detection of S. aureus on the primary plate.

Agar↗
PubMed2006

Enterotoxigenic Escherichia coli colonization factor types collected from 1997 to 2001 in US military personnel during operation Bright Star in northern Egypt.

Operation Bright Star (OBS) is a biennial, multinational exercise in Egypt involving 15000 US troops. Consistent with past observations in deployed troops, diarrhea is the most significant cause of morbidity. Focused efforts are ongoing to develop vaccines against the most common pathogens affecting our troops. As part of these efforts, diarrhea surveillance was conducted during OBS to monitor pathogens associated with illness and to identify new vaccine targets. A retrospective review was conducted of prior studies with similar methods. Soldiers with diarrhea presenting to the OBS clinic provided a stool sample that was inoculated into Carey-Blair transport media. Within 3 days, the Cary-Blair tubes were transported to the Naval Medical Research Unit no. 3 in Cairo where bacterial culture was performed. As part of the evaluation, 5 Escherichia coli-like colonies were collected and tested for toxin production using the GM1-ELISA. Toxin-positive isolates were further tested for colonization factors (CF) by a dot-blot assay using a standardized panel of monoclonal antibodies against CFA/I, CS1-CS7, CS17, CS8 (CFA/III), CS12 (PCFO159), and CS14 (PCFO166). Enterotoxigenic E. coli (ETEC) was the most frequently isolated pathogen during each OBS from which data were collected. The rate of ETEC-associated diarrhea ranged from 22% to 58%. Over time, there were dramatic shifts in the frequency and distribution of CFs. Over the 5 years of study, an increasing number of ETEC isolates had no known CF identified, and in 2001, only 40% of ETEC was associated with known CFs. The most commonly identified CF was CS6. Diarrheal disease, particularly ETEC, continues to be a common malady among US military personnel deployed to Egypt. We have identified ETEC CF types, especially CS6, which should be considered potential vaccine candidates. However, despite intensive testing, CFs could not be identified in most of the ETEC isolated, highlighting the need for further studies to identify novel CFs and alternative vaccine targets.

Antibodies, Monoclonal↗
PubMed2004

Methods for the isolation and identification of Listeria spp. and Listeria monocytogenes: a review.

Listeria monocytogenes is an important food-borne pathogen and is widely tested for in food, environmental and clinical samples. Identification traditionally involved culture methods based on selective enrichment and plating followed by the characterization of Listeria spp. based on colony morphology, sugar fermentation and haemolytic properties. These methods are the gold standard; but they are lengthy and may not be suitable for testing of foods with short shelf lives. As a result more rapid tests were developed based on antibodies (ELISA) or molecular techniques (PCR or DNA hybridization). While these tests possess equal sensitivity, they are rapid and allow testing to be completed within 48 h. More recently, molecular methods were developed that target RNA rather than DNA, such as RT-PCR, real time PCR or nucleic acid based sequence amplification (NASBA). These tests not only provide a measure of cell viability but they can also be used for quantitative analysis. In addition, a variety of tests are available for sub-species characterization, which are particularly useful in epidemiological investigations. Early typing methods differentiated isolates based on phenotypic markers, such as multilocus enzyme electrophoresis, phage typing and serotyping. These phenotypic typing methods are being replaced by molecular tests, which reflect genetic relationships between isolates and are more accurate. These new methods are currently mainly used in research but their considerable potential for routine testing in the future cannot be overlooked.

Animals↗
PubMed2006

Inhibition of the growth of Paenibacillus larvae, the causal agent of American foulbrood of honeybees, by selected strains of aerobic spore-forming bacteria isolated from apiarian sources.

The bacterium Paenibacillus larvae, the causative agent of American foulbrood disease of honeybee larvae, occurs throughout the world and is found in many beekeeping areas of Argentina. The potential as biocontrol agents of antagonic aerobic spore-forming bacteria isolated from honey samples and other apiarian sources were evaluated. Each isolate was screened against one strain of Paenibacillus larvae (ATCC 9545) by using a perpendicular streak technique. Ten randomly selected bacterial strains from the group that showed the best antagonistic effect to P. larvae ATCC 9545 were selected for further study. These were identified as Bacillus subtilis (m351), B. pumilus (m350), B. licheniformis (m347), B. cereus (mv33), B. cereus (m387), B. cereus (m6c), B. megaterium (m404), Brevibacillus laterosporus (BLAT169), B. laterosporus (BLAT170), and B. laterosporus (BLAT171). The antagonistic strains were tested against 17 P. larvae strains from different geographical origins by means of a spot test in wells. The analysis of variance and posterior comparison of means by Tukey method (P < 0.01) showed that the best antagonists were B. megaterium (m404), B. licheniformis (m347), B. cereus (m6c), B. cereus (mv33), and B. cereus (m387).

Animals↗
PubMed2005

Rapid phenotypic characterization of Salmonella enterica strains by pyrolysis metastable atom bombardment mass spectrometry with multivariate statistical and artificial neural network pattern recognition.

Pyrolysis mass spectrometry was investigated for rapid characterization of bacteria. Spectra of Salmonella were compared to their serovars, pulsed-field gel electrophoresis (PFGE) patterns, antibiotic resistance profiles, and MIC values. Pyrolysis mass spectra generated via metastable atom bombardment were analyzed by multivariate principal component-discriminant analysis and artificial neural networks (ANNs). Spectral patterns developed by discriminant analysis and tested with Leave-One-Out (LOO) cross-validation distinguished Salmonella strains by serovar (97% correct) and by PFGE groups (49%). An ANN model of the same PFGE groups was cross-validated, using the LOO rule, with 92% agreement. Using an ANN, thirty previously unseen spectra were correctly classified by serotype (97%) and at the PFGE level (67%). Attempts by ANN to model spectra grouped by resistance profile-but ignoring PFGE or serotype-failed (10% correct), but ANNs differentiating ten samples of the same serotype/PFGE class were more successful. To assess the information content of PyMS data serendipitously associated with or directly related to resistance character, the ten isolates were grouped into four, three, or two categories. The four categories corresponded to four resistance profiles. The four class and three class ANNs showed much improved but insufficient modeling power. The two-class ANN and a corresponding multivariate model maximized inferential power for a coarse antibiotic-resistance-related distinction. They each cross-validated by LOO at 90%. This is the first direct correlation of pyrolysis metastable atom bombardment mass spectrometry with immunological (e.g. serology) or molecular biology (e.g. PFGE) based techniques.

Bacterial Typing Techniques↗
PubMed2005

A new genetic test for the rapid identification of shiga-toxines producing (STEC), enteropathogenic (EPEC) E. coli isolates from children.

Routine bacteriological techniques do not allow detection of the most frequent enteric pathogens in young children: enteropathogenic Escherichia coli (EPEC) and shigatoxinogenic E. coli (STEC/EHEC). Since there is no correlation between serotype and pathotype, a genotypic determination is therefore necessary for the identification of these pathogenic strains. We evaluated the Genotype EHEC test (Hain Life Science, Germany), a new rapid system based on DNA multiplex amplification and further hybridization for the detection of shigatoxin stx1, stx2 genes, intimin eae gene and invasin ipaH gene harbored by Shigella and enteroinvasive E. coli (EIEC). E. coli strains of various serogroups isolated from children with acute gastroenteritis, hemorrhagic colitis or hemolytic-uremic syndrome were tested. Their genotypes were first determined by standard in-house PCR. The strains collection included 11 STEC/EHEC (serogroups O157, O111, O26, O91, O-untypable) and nine EPEC (serogroups O26, O157, O55, O126, O127, O-untypable). The same strains were tested with Genotype EHEC. For all the strains, the hybridization banding pattern obtained by Genotype EHEC correlated with their expected genotypic characteristics. No specific equipment is required, except a thermocycler. Absence of electrophoresis system, of ethidium bromide staining and imaging system is a clear-cut advantage of Genotype EHEC. In addition, the short testing time (less than 2 h) optimizes treatment orientation. The Genotype EHEC test allows an easy and reliable identification of EHEC, STEC, EPEC and also EIEC. As such, it is a useful tool for the rapid diagnosis of diarrheal diseases.

Child↗
PubMed2007

Bacterial flora and risk of infection of the ovine teat duct and mammary gland throughout lactation.

We collected samples of teat duct material and mammary secretion from ewes in three farms (flock A, polyparous n=7; flock B, polyparous n=6, primiparous n=4; flock C, polyparous n=4): 14 samples immediately after lambing (before sucking of lambs), 244 samples during the suckling period and 156 samples during the milking period. Conventional bacteriological techniques were used. The results were modeled using survival analysis, initially by the Kaplan-Meier method and then by the Cox Proportional Hazards method. Then, we calculated the minimum true risk of an "at-risk" teat or mammary gland being infected and analyzed these data with STATA using the GLLAMM program for Generalised Linear Latent and Mixed Models. During the suckling period, bacteria were isolated from 52 (21%) duct material and 19 (8%) secretion samples; respective results for the milking period were 20 (13%) and 9 (6%). There was an increased risk of duct rather than secretion samples being infected (P<0.001). There was a significant difference among flocks in isolating bacteria from duct (P<0.01) or secretion (P<0.001) samples during suckling period, but not during hand-milking period (P>0.4 and 0.1, respectively). There were no differences between isolation of bacteria from duct (P>0.5) or secretion (P>0.7) samples among primiparous and polyparous animals. Most bacterial isolates were staphylococci. Persistent isolation of the same bacterial species from duct material samples obtained from a particular ewe was recorded with five Staphylococcus spp. and two Mannheimia haemolytica isolates. The results indicate that infections of the teat duct can take place easily; however, not all infections result to infection of the mammary gland. The results support experimental evidence that defence mechanisms of the healthy teat are able to limit the infection. Maintenance of healthy teats contributes to effective defence mechanisms, and coupled with minimal infections of the teat duct, would contribute to the prevention of mastitis in ewes.

Animals↗
PubMed1999

Leukocytes in semen from men with spinal cord injuries.

OBJECTIVE: To assess the leukocyte populations in semen samples from men with spinal cord injuries (SCIs) and their relation to sperm motility. DESIGN: Cross-sectional study. SETTING: A joint spinal cord injury and fertility clinic at an academic tertiary referral center for fertility treatment and a university-based department of immunology. PATIENT(S): Nine men with chronic SCIs and seven healthy sperm donors as controls. INTERVENTION(S): Semen samples were obtained by electroejaculation from men with SCIs and by masturbation from donors. MAIN OUTCOME MEASURE(S): Leukocyte populations determined by immunohistochemical techniques, bacteriologic assessment of urine, and sperm density and motility. RESULT(S): The most cellular specimens were antegrade specimens obtained from men with SCIs and coexisting urinary tract infections. The highest proportion of leukocytes occurred in retrograde samples from men with SCIs and urinary tract infections. The most predominant leukocytes in all specimens were granulocytes. Infection increased the number of T cells and the degree of cell activation. There was no significant correlation between leukocyte populations and total motile sperm counts. CONCLUSION(S): Increased numbers of leukocytes in semen samples from men with SCIs are the result of urinary tract infections. The reduced sperm motility seen in men with SCIs does not correlate with the numbers of leukocytes; therefore, other factors also contribute to the semen abnormalities in these patients.

Adult↗
PubMed1988

Current concepts in the pathogenesis and management of brain abscesses in children.

Brain abscesses represent the most frequent intracranial suppurative process occurring in children. Improved bacteriologic techniques for isolating anaerobic microorganisms have shown that anaerobes play a major role in brain abscesses in conjunction with aerobic organisms such as alpha-streptococci. Computerized tomography has improved the diagnosis of brain abscesses and has changed the management in certain circumstances. Although surgical drainage still remains the definitive treatment modality, conservative medical management with serial CT scans has been successful. Still, the mortality and morbidity of brain abscesses remain substantial.

Brain Abscess↗
PubMed2002

Bacteriological and epidemiological findings during examination of the uterine content of ewes with retention of fetal membranes.

We included 92 pairs of ewes with or without retention of fetal membranes in a cohort study of 25 flocks in Southern Greece. We obtained two uterine content samples under aseptic conditions, by introducing a swab into the uterus of these ewes, on the 2nd-4th and the 5th-9th day after lambing. We used conventional bacteriological techniques to isolate and identify bacteria and to carry out antimicrobial agents susceptibility testing. The prevalence of bacterial intrauterine contamination among ewes with retention was 24% on the first and 46% on the second sampling (P < 0.0001) and that among ewes without retention was 8 and 2% (P > 0.05), respectively. Clinical signs accompanying the retention of fetal membranes were more frequently observed among ewes with intrauterine contamination than among those without (P = 0.0007). The odds of an ewe having an intrauterine contamination increased multiplicatively by 1.06 when the median duration of retention in the flock increased by 6 h. The principal bacteria isolated from the ewes with retention were Arcanobacterium pyogenes and Escherichia coli; 21% of 73 isolates tested were found resistant to at least one antimicrobial agent.

Actinomycetaceae↗