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[Incidence and significance of pathogen detection in Douglas fluid in non-inflammatory genital diseases].

Between 1976 and 1986 the secretions from the pouch of Douglas of 1,219 patients with non-inflammatory genital diseases were microbiologically studied. Microorganisms were detected in 3.4%. In the majority of cases they were physiological skin organisms, with a count of less than 10 per ml of Douglas fluid. These findings support the view, that secondary contamination of the specimens occurred during removal, transportation, or laboratory processing.

Bacteria↗

Mismatch cleavage detects pathogenic microorganisms.

When a DNA probe hybridizes a DNA target and generates a G/A mismatch in the probe-target DNA heteroduplex, the mismatch enzyme, mutY, will cut the A base at the site of the mismatch. This specific cleavage at the mismatched A on the known probe will reveal the complementary DNA sequences of the targets. This study shows mismatch cleavage assays identify the complementary sequence of cryptic plasmid target in the extract of chlamydia infected cells in culture. In addition, the specific cleavage at a single base permits differentiation of two sequences with one base difference. This was shown in differentiating the subtypes of human immunodeficiency virus (HIV) type 1. The addition of amines in the assays increases the sensitivity by freeing the target for recycling. The combined assay system of high sensitivity and demonstrated specificity allows further evaluation for direct identification of pathogenic microorganisms in patient samples.

Acetates↗

How C-type lectins detect pathogens.

Glycosylation of proteins has proven extremely important in a variety of cellular processes, including enzyme trafficking, tissue homing and immune functions. In the past decade, increasing interest in carbohydrate-mediated mechanisms has led to the identification of novel carbohydrate-recognizing receptors expressed on cells of the immune system. These non-enzymatic lectins contain one or more carbohydrate recognition domains (CRDs) that determine their specificity. In addition to their cell adhesion functions, lectins now also appear to play a major role in pathogen recognition. Depending on their structure and mode of action, lectins are subdivided in several groups. In this review, we focus on the calcium (Ca(2+))-dependent lectin group, known as C-type lectins, with the dendritic cell-specific ICAM-3 grabbing non-integrin (DC-SIGN) as a prototype type II C-type lectin organized in microdomains, and their role as pathogen recognition receptors in sensing microbes. Moreover, the cross-talk of C-type lectins with other receptors, such as Toll-like receptors, will be discussed, highlighting the emerging model that microbial recognition is based on a complex network of interacting receptors.

Animals↗

Evaluation of two real-time polymerase chain reaction pathogen detection kits for Salmonella spp. in food.

AIMS: To evaluate the LightCycler Salmonella Detection Kit and the TaqMan Salmonella Gold Detection and Quantitation Kit for the real-time PCR detection of Salmonella in various food samples. METHODS AND RESULTS: Ready-to-eat foods and raw food samples were artificially contaminated with Salmonella serotypes. In the specificity test, bacterial DNA extracted from sample pre-enrichment culture was analysed with the detection kits performed respectively on the LightCycler Instrument or the ABI Prism 7000 Sequence Detection System. No false-positive or false-negative results were obtained, although the LightCycler system generated invalid PCR results on two occasions. In the sensitivity test using the LightCycler system, Salmonella could be detected in pre-enrichment cultures of 25-g samples inoculated with as low as 1.5 x 10(3) CFU (depending on food type), and false-negative results were obtained for samples with low inoculum levels. CONCLUSIONS: Two commercial kits for real-time PCR detection of Salmonella were evaluated. SIGNIFICANCE AND IMPACT OF THE STUDY: Evaluation using more food types and matrices, and foods that contain low number of Salmonella or high number of other competing bacteria, is needed before adopting the real-time PCR technique for routine food tests.

Bacteriological Techniques↗

Tickborne pathogen detection, Western Siberia, Russia.

Ixodes persulcatus (n = 125) and Dermacentor reticulatus (n = 84) ticks from Western Siberia, Russia, were tested for infection with Borrelia, Anaplasma/Ehrlichia, Bartonella, and Babesia spp. by using nested polymerase chain reaction assays with subsequent sequencing. I. persulcatus ticks were infected with Borrelia burgdorferi sensu lato (37.6% +/- 4.3% [standard deviation]), Anaplasma phagocytophilum (2.4% +/- 1.4%), Ehrlichia muris (8.8% +/- 2.5%), and Bartonella spp. (37.6% +/- 4.3%). D. reticulatus ticks contained DNA of B. burgdorferi sensu lato (3.6% +/- 2.0%), Bartonella spp. (21.4% +/- 4.5%), and Babesia canis canis (3.6% +/- 2.0%). Borrelia garinii, Borrelia afzelii, and their mixed infections were observed among I. persulcatus, whereas B. garinii NT29 DNA was seen in samples from D. reticulatus. Among the I. persulcatus ticks studied, no Babesia spp. were observed, whereas B. canis canis was the single subspecies found in D. reticulatus.

Anaplasma phagocytophilum↗

[Rapid bioluminescence method for pathogen detection of nephropyelitis patient].

ATP is a kind of necessary metabolites in the living cells. We detected ATP contents in 222 bacteriuria or the urine germ by bioluminescence method. The results showed that the patient had been infected when the mean value was > 130.9 +/- 11.38 and had not when the mean value was < 32.9 +/- 2.26. The results were the same with the Gram Stain, L-form bacteriuria culture and the common bacteriuria culture. The mean values of positive specimens are higher than that of the negative specimens by the bioluminescence. Thus, it is indicated that the bioluminescence method has high sensitivity. This method can be used to detect L-form bacteriuria in the urine germ quickly and is important for early diagnosis by the doctors.

Adenosine Triphosphate↗

[Infections with Borrelia burgdorferi in Würzburg blood donors: antibody prevalence, clinical aspects and pathogen detection in antibody positive donors].

The prevalence of antibodies against Borrelia burgdorferi, the etiologic agent of Lyme borreliosis, was determined in a group of blood donors from the Würzburg area (Southern Germany). 26 of 472 donors (5.5%) tested positive in a hemagglutination test. When performing immunoblots only 13 donors (2.7%) gave rise to B. burgdorferi-specific antibodies. 9 of them were examined in more detail by anamnesis, physical examination, determination of inflammation parameters of the blood and polymerase chain reaction (PCR) analysis of urine. All persons were asymptomatic for Lyme borreliosis. One of 4, who remembered a tick bite, actually had suffered from an erythema migrans 5 years ago. Another one had been affected by fever, headaches and pains in the limbs, arthralgia and motoric disorder in both hands 6 months before examination. Analysis of the blood did not provide any evidence of an acute infection. In the urine of 2 donors we detected B. burgdorferi-specific DNA by PCR. No seroconversion due to blood transfusion could be observed, when 9 recipients of blood products provided by the 13 seropositive donors were serologically reexamined. PCR analysis of urine samples of 5 recipients was also negative.

Antibodies, Bacterial↗

[Microscopy procedures for direct pathogen detection in Lyme borreliosis].

Dark-field microscopy, fuchsin stain and Fontana silver stain were used for a rapid detection of spirochaetes in fresh materials from patients with Lyme-borreliosis. The spirochaetes were shown to be present in 2 cerebrospinal fluids, 2 synovial fluids and in one brain cyst fluid. It is pointed out that these techniques require further improvement and optimization.

Bacteriological Techniques↗

[Value of detecting pathogens in fertility disorders].

The present study was carried out on 1092 asymptomatic male patients suffering from unexplained infertility without any history or clinical signs of inflammatory diseases of the genital tract. Semen samples were cultured for mycoplasma. In 214 of the patients, we additionally performed bacteriological investigations on seminal fluid, smears from the glans penis or prepuce, and urine specimens. Semen analysis included the common ejaculate parameters. We found significantly elevated counts of mycoplasma in 13% of the semen samples examined; pathogenic isolation rates of bacteria were observed in 36%. Increased counts of various bacterial species associated with high numbers of mycoplasma seem to be one of the causative factors in male infertility. There was not observed any close relationship between the recovery of microorganism and poor semen quality, except for fructose and citrate. When follow-up investigations were carried out in untreated patients, the concentrations of mycoplasma and bacteria in the semen fluid revealed a spontaneous variability of considerable extent, indicating frequent contamination of the semen. Therefore, we recommend to perform a culture control test of the semen prior to specific antibiotic treatment.

Adult↗

Investigations of milk quality from teats with milk flow disorders.

The objective of this study was to investigate the quality of milk from teats with milk flow disorders. Somatic cell count, pathogens, and signs of mastitis (>100,000 cells/ml and pathogens detected) were determined in the milk from all teats of the udder before treatment of the affected teat, as well as 1 and 6 mo later. Teats with milk flow disorders were compared to all of the other teats from the same udder. Before treatment, the SCC from affected teats was 4.3 million higher, the odds of detecting pathogens 6 times higher, and the odds of mastitis 11 times higher than in control teats (when adjusted for other significant explanatory variables). SCC and the risk of mastitis decreased after surgical treatment of the affected teats, whereas the chance of detecting pathogens was not affected. Six months after treatment, the SCC was 1.3 million higher, and the odds of mastitis 6.5 times higher than in control teats. Throughout the study period neither SCC, the odds of detecting pathogens, nor mastitis changed significantly in control teats. It may be concluded from this study that milk quality from teats with milk flow disorders is decreased before treatment and does not reach the milk quality from unaffected teats within 6 mo after treatment.

Animals↗

Use of DNA hybridization to detect vaginal pathogens associated with bacterial vaginosis among asymptomatic pregnant women.

OBJECTIVE: The purpose of this study was to determine whether microbial DNA hybridization is a useful method to study bacterial vaginosis in asymptomatic pregnant women. STUDY DESIGN: Vaginal specimens were collected at <26 weeks' gestation from 230 women, and analyzed for bacterial vaginosis by both Gram stain using Nugent criteria and DNA hybridization for Gardnerella vaginalis, Prevotella bivia, Bacteroides ureolyticus, and Mobiluncus curtisii. Results were analyzed using McNemar's paired test and chi-square test for trend, with significance set at P < .05. RESULTS: By Gram stain, 60 (26.1%) of 230 were positive for bacterial vaginosis, and 134 (58.3%) were negative. By DNA hybridization, 99 (43%) were positive for at least 1 pathogen, and DNA results were significantly associated with Gram-stain results (P < .01). As the Nugent score progressed from normal to abnormal flora, the proportion with >1 pathogen detected by DNA hybridization increased significantly (P < .001). CONCLUSION: DNA hybridization may be a useful method to study shifts in vaginal flora during pregnancy.

DNA↗