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PubMed1998

Diarrhea in returning Austrian tourists: epidemiology, etiology, and cost-analyses.

BACKGROUND: Between 1995 and 1997, stool samples of 322 Austrian tourists returning from abroad with diarrhea were examined for bacteria, parasites and viruses. METHODS: Epidemiologic data were collected from information furnished by physicians and hospitals and from questionnaires. Moreover, testing expenses and additional cost for treated cases were evaluated. RESULTS: In 97 of 322 patients examined (30%), one or more pathogens were detected in the stool. Bacteria were found in 38 patients (39%), parasites in 33 patients (34%) and viruses in 26 patients (27%). In 6 patients, mixed infections with parasites and viruses were detected and in 5 patients with bacteria and viruses. Among bacteria, Campylobacter jejuni was most frequent; among parasitic infections, Giardia lamblia. Significant correlations were established between the country of destination, age, travel style and length of stay. Forty-four percent of all patients visited Asia (including Turkey), 27% Africa, 18% Latin America, and only 10% southern Europe. The group between 20 and 29 years of age was most frequently affected (p<.001), the group between 0 and 19 years of age least. Fifty-seven percent stayed in a hotel without frequent changes of location; 43% undertook a trekking trip; and of those, 75% belonged to the group aged between 20 and 39. In terms of the correlation between travel style and pathogen, it was found that 74% of patients with bacterial infections stayed in a hotel (avg. 57.9%; p<.05) whereas 64% of all patients with parasitic infections undertook a trekking trip (avg. 42%; p<.001). Thirty-six percent of all patients with parasitic infections spent their vacation in India (avg. 13%; p<.001). The length of stay of patients with bacterial infections was shorter than average (72% spent between 1 and 2 weeks abroad, avg. 49.8%). Patients with parasitic infections spent significantly more time abroad than average (42% more than 2 months; avg. 17.7%; p<.001). Average cost of specific antimicrobial therapy was U.S.$31 whereas the average cost of identifying a patient needing such treatment was almost U.S.$580. CONCLUSION: Optimal detection rate and cost reduction for the diagnosis require precise history, adequate collection of samples using adequate transport media, and rapid transfer to the laboratory.

Adolescent↗

PubMed2004

The IHPK1 gene is disrupted at the 3p21.31 breakpoint of t(3;9) in a family with type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM) is a group of multifactorial disorders due to either defective insulin secretion or action. Despite the fact that numerous genetic researches of T2DM have been pursued, the pathogenic mechanisms remain obscure. We encountered a T2DM family associated with a balanced reciprocal translocation, t(3;9)(p21.31;q33.1). To isolate a candidate gene susceptible to T2DM, we constructed physical maps covering both the 3p and 9q breakpoints of the translocation in the family. Consequently, the inositol hexaphosphate kinase 1 gene ( IHPK1) (OMIM *606991) was found to be disrupted at the 3p21.31 breakpoint. We then carried out sequence analysis for all coding regions of IHPK1 in 405 unrelated T2DM patients in order to validate whether aberrations of the gene are common in T2DM patients, but we failed to detect any pathogenic changes. The disruption of IHPK1 or another predisposing gene affected by position effect of the translocation may explain the T2DM phenotype at least in this family. Alternatively, the IHPK1 disruption in the family is a chance association.

Adolescent↗

PubMed2004

The occurrence of campylobacters in water sources in South Africa.

Campylobacter spp., mainly C. jejuni and C. coli, are recognized as significant human bacterial pathogens, being responsible for increasing numbers of gastroenteritis cases worldwide. Several reports have indicated that environmental waters are potential reservoirs and transmitting vehicles for these bacteria. The purpose of this study was thus to examine the occurrence of campylobacters in drinking and environmental water sources of South Africa, a country with a warmer climate and higher microbial pollution levels than those previously addressed in the Northern Hemisphere where similar investigations have been undertaken. Various types of water samples (five drinking water, four ground water, 11 surface water and four raw sewage) were collected from different parts of South Africa. Detection was by enrichment in Bolton broth prior to plating on both selective mCCDA or through a 0.6microm membrane filter on non-selective blood agar isolation media. Out of 100 initially selected Campylobacter-like isolates, only 22 did not grow aerobically and were subsequently identified as Campylobacter spp. by biochemical tests. However, the results obtained by 16S rRNA sequence analysis indicated that only three of these strains (13.6%) were Campylobacter jejuni and the remaining 19 strains were identified as Arcobacter butzleri. The spread of Arcobacter via water warrants further investigation, especially in view of the higher levels of detection and pathogenic nature of these bacteria.

Campylobacter↗

PubMed2005

Innate control of adaptive immunity via remodeling of lymph node feed arteriole.

The adaptive immune system relies on rare cognate lymphocytes to detect pathogen-derived antigens. Naïve lymphocytes recirculate through secondary lymphoid organs in search of cognate antigen. Here, we show that the naïve-lymphocyte recirculation pattern is controlled at the level of innate immune recognition, independent of antigen-specific stimulation. We demonstrate that inflammation-induced lymphocyte recruitment to the lymph node is mediated by the remodeling of the primary feed arteriole, and that its physiological role is to increase the efficiency of screening for rare antigen-specific lymphocytes. Our data reveal a mechanism of innate control of adaptive immunity: by increasing the pool of naïve lymphocytes for detection of foreign antigens via regulation of vascular input to the local lymph node.

Animals↗

PubMed1996

The dynamics of microbial colonization of barrier membranes for guided tissue regeneration.

The microbial colonization of expanded polytetrafluoroethylene membrane by putative periodontopathogens at 3 minutes of intraoral manipulation was determined in 42 patients with 42 mandibular posterior two- to three-wall defects. Twenty patients exhibited no periodontal pockets of > or = 5 mm, other than the study site, and low levels of pathogens (group A). Twenty-two patients revealed multiple periodontal pockets of 5 mm or more and numerous pathogens (group B). Within the preceding 3 months of regenerative surgery, group A patients had received apically positioned flap surgery with osseous recontouring (except for the study site), and group B patients had been enrolled in a non-surgical maintenance program. The subgingival microbiota was examined prior to regenerative therapy, and the membrane microbiota was examined at 3 minutes and at the time of removal at 6 weeks by culture, DNA probes, and phase-contrast microscopy. The mean initial defect depth was 7.4 mm for group A and 7.2 mm for group B. At 6 months, the difference in mean clinical attachment gain was statistically significant (P < 0.001; group A: 3.4 mm; group B: 1.4 mm). At 3 minutes, putative pathogens were detected in seven (16.7%) membranes in group B (group Binfected), and the associated sites gained only 0.6 mm in clinical attachment at 6 months. Clinical attachment gain was modeled as a linear function of the explanatory variables (r2 = 86%). The presence of Porphyromonas gingivalis detected by DNA probe at 3 minutes was associated with 1.5 mm less expected gain (P = 0.0002). Total microbial counts and the percentage of Peptostreptococcus micros and Capnocytophaga species at baseline, and of motile rods on the membrane surface facing the gingiva at 6 weeks, were statistically significant negative predictors of clinical attachment. For each week the membrane remained covered, an additional 0.5 mm gain could be expected (P = 0.002); and for every 10 sites that exhibited bleeding on probing, the clinical attachment gain was 0.6 mm less at the site of regeneration (P < 0.0001). The present results showed that putative pathogens may colonize membranes within 3 minutes of intraoral manipulation. The patient group treated with periodontal osseous surgery revealed the lowest levels of periodontal pathogens in the membranes and exhibited the most gain in clinical attachment.

Adult↗

PubMed2002

Intrinsic sphincter deficiency: do the maximum urethral closure pressure and the Valsalva leak-point pressure identify different pathogenic mechanisms?

A prospective analysis of 166 women with genuine stress incontinence was performed comparing Valsalva leak-point pressure (VLPP) and maximum urethral closure pressure (MUCP) with age, previous urogynecologic surgery and/or hysterectomy, poor urethral mobility, weight, menopause and vaginal deliveries, to find correlations with intrinsic sphincter deficiency (ISD). Cut-off value for VLPP were 60 cmH2O and for MUCP 30 cmH2O. MUCP < or = 30 cmH2O identifies a group of patients with more severe incontinence, a shorter urethral functional length (UFL) (P = 0.02), more previous urogynecologic operations and the menopause (P = 0.004 and P = 0.000), and older age (P = 0.000). VLPP < or = 60 cmH2O identifies a group of patients with more severe incontinence, a shorter UFL (P = 0.005), more previous urogynecologic surgery (P=0.006) and poorer urethral mobility (P = 0.004). As these two tests measure different components of urethral functions we can hypothesize that they detect different pathogenic processes contributing to ISD. When one or both tests is abnormal incontinence is more severe and the incidence of poor prognostic factors is increased.

Aged↗

PubMed1995

Development of specific DNA probes and their usage in the detection of Plasmodium vivax infection in blood.

The application of nucleic acid probes, in the detection of pathogenic micro-organisms, has become an integral part of diagnostic technologies. In this study, Plasmodium vivax-specific DNA probes have been identified by carrying out genomic subtractive hybridization. In this approach, the recombinant clones from a P. vivax genomic library are screened with radiolabelled human and P. falciparum DNA. The colonies which react with labelled P. falciparum and human DNA are eliminated and those which do not produce any autoradiographic signal have been subjected to further screening procedures. Three P. vivax specific DNA probes have been obtained by these repeated screenings. Further analyses indicate that these probes are specific and sensitive enough to detect P. vivax infection in clinical blood samples when used in a non-radioactive DNA hybridization assay.

Animals↗

PubMed2002

Sequence of the Escherichia coli O26 O antigen gene cluster and identification of O26 specific genes.

Escherichia coli associated with outbreaks of gastroenteritis and hemolytic uremic syndrome include clones with O antigens O157 and O111. However, O26 has emerged as an O antigen present in pathogenic strains, particularly those implicated in cases of infantile gastroenteritis worldwide. The O26 O antigen gene cluster was sequenced. It was found to contain the genes expected for biosynthesis of nucleotide sugars L-rhamnose, N-acetyl-L-fucosamine and N-acetyl-glucosamine, as well genes for O unit flippase, O antigen polymerase and potential transferase genes. By polymerase chain reaction testing against representative strains for the 166 Escherichia coli O serogroups and some randomly selected Gram-negative bacteria, we identified three O antigen genes that are highly specific to O26. This work provides the basis for a sensitive test for the rapid detection of pathogenic clones with the O26 antigen, which has implications for public health, especially in the control of food-borne outbreaks.

DNA, Bacterial↗

PubMed1996

Pharmacokinetics and clinical effects of cefozopran in pediatric patients.

An investigation was made into pharmacokinetics and clinical effects of the newly-developed cephem antibiotic for injection, cefozopran (SCE-2787, CZOP), in pediatric patients. In 26 patients in whom pharmacokinetics were investigated, peak serum concentrations of CZOP administered at doses of 10, 20 and 40 mg/kg by i.v. injection were 21.3 +/- 10.0 (mean +/- standard deviation), 51.0 +/- 9.9 and 68.3 +/- 0.7 micrograms/ml, respectively. Serum concentrations at 6 hours after administration were 2.9 +/- 1.7, 2.3 +/- 0.9 and 4.6 +/- 2.6 micrograms/ml, with the levels roughly above MIC90s for dominating pathogenic bacteria being maintained until 6 hours after treatment. Urine concentrations were in the range between 200 and 560 micrograms/ml at 4 to 6 hours after dosing. Cumulative urine excretion accounted for 70 to 80% of dose. In 11 patients in whom pharmacokinetic investigations were performed, peak serum concentrations of CZOP administered at doses of 10, 20 and 40 mg/kg by 30-min. i. v. drip infusion were 37.1, 66.3 +/- 25.5 and 95.7 +/- 8.9 micrograms/ml, respectively. Serum concentrations at 6 hours after dosing were 1.6, 2.3 +/- 0.8 and 3.0 +/- 0.4 micrograms/ml, respectively, with the levels above MIC90s for dominating pathogenic bacteria also being maintained until 6 hours after administration. Urine concentrations were 190 micrograms/ml or more until 8 hours after dosing and the cumulative urinary excretion accounted for 50 to 70% of dose. In 9 patients with meningitis in whom CZOP penetration into cerebrospinal fluid was investigated, concentrations in the fluid of the compound i.v. injected at doses from 40 to 53 mg/kg were in the range between 1.6 and 43.4 micrograms/ml exceeding MICs for pathogenic bacteria at 1 to 1.5 hours after dosing. In all of the 38 patients in whom pharmacokinetic investigations and clinical evaluations were performed, CZOP was good to excellent (excellent in 22 patients and good in 16 patients). Also in bacteriological evaluations, all of the 31 strains of investigated pathogenic bacteria were eradicated. The clinical efficacy rates for the 335 subjects for clinical evaluations were 97.0% (195/201) for patients in whom pathogenic bacteria were detected (group A), and 95.5% (128/134) for patients in whom no pathogenic bacteria were detected (group B). In bacteriological evaluations, the eradication rates of Gram-positive and Gram-negative bacteria were 96.3% (77/80) and 94.5% (155/164), respectively, with the eradication rate in total being 95.1% (232/244). Safety investigations were performed in 364 patients. Adverse reactions were reported in 11 patients (3.0%), including diarrhea (aqueous stool and soft stool) in 7 patients (1.9%) and drug rash (rash, eruption and wheal) in 4 patients (1.1%). Abnormal laboratory test values were noted in 54 patients, including eosinophilia in 20 patients (6.3%) and elevated GPT in 20 patients (6.3%). The adverse reactions and abnormal laboratory test values were not serious, disappearing or improving during the continued treatment period or as a result of discontinuation of the treatment. Serum and urine concentrations of CZOP, when administered by i.v. injection and 30-min, i.v. drip infusion at doses of 10, 20 and 40 mg/kg, were higher than the MICs for pathogenic bacteria until 6 hours after dosing. The drug also showed favorable penetration into cerebrospinal fluid. It was therefore considered that CZOP was a highly useful drug for the treatment of pediatric infections with sufficient bacteriological and clinical efficacy when administered at a dose of 40 to 80 mg/kg three to four times daily.

Bacteria↗

PubMed2002

Environmental impact on the bacteriological quality of domestic water supplies in Lagos, Nigeria.

OBJECTIVE: To assess the impact of town planning, infrastructure, sanitation and rainfall on the bacteriological quality of domestic water supplies. METHODS: Water samples obtained from deep and shallow wells, boreholes and public taps were cultured to determine the most probable number of Escherichia coli and total coliform using the multiple tube technique. Presence of enteric pathogens was detected using selective and differential media. Samples were collected during both periods of heavy and low rainfall and from municipalities that are unique with respect to infrastructure planning, town planning and sanitation. RESULTS: Contamination of treated and pipe distributed water was related with distance of the collection point from a utility station. Faults in pipelines increased the rate of contamination (p<0.5) and this occurred mostly in densely populated areas with dilapidated infrastructure. Wastewater from drains was the main source of contamination of pipe-borne water. Shallow wells were more contaminated than deep wells and boreholes and contamination was higher during period of heavy rainfall (p<0.05). E. coli and enteric pathogens were isolated from contaminated supplies. CONCLUSIONS: Poor town planning, dilapidated infrastructure and indiscriminate siting of wells and boreholes contributed to the low bacteriological quality of domestic water supplies. Rainfall accentuated the impact.

City Planning↗

PubMed1996

Differential cytology of bronchoalveolar lavage fluid in immunosuppressed children with pulmonary infiltrates.

OBJECTIVE: Bronchoalveolar lavage (BAL) is a well established technique for the detection of pathogens in immunosuppressed children, but its diagnostic yield is variable. The aim of this study was to investigate whether BAL differential cell counts are helpful in the evaluation of pulmonary infiltrates in immunocompromised children. STUDY DESIGN: BAL was performed 28 times in 27 febrile immunocompromised children with pulmonary infiltrates. All patients were pretreated with broad spectrum antibiotics; 11 children also received amphotericin B. BAL was conducted with a flexible bronchoscope wedged in the area of maximal pathology as suggested by the chest radiograph or in the middle lobe in patients with diffuse interstitial radiographic changes. Differential cell counts were performed from cell smears obtained after centrifugation of BAL fluid. RESULTS: Bacterial or fungal organisms were detected in BAL fluid of 12 patients. Patients with bacterial or fungal infections (group 1) had a significantly higher percentage of granulocytes in BAL fluid both compared with patients with sterile BAL cultures (group 2) and with a control group of children without pulmonary disease (p < 0.001, Wilcoxon test). The proportion of lymphocytes was not different from the control group in group 1 but significantly increased in group 2 (p < 0.001, Wilcoxon test). Blood differential cell counts were not different in the two patient groups. Lymphocyte subsets of BAL fluid obtained in a subgroup of patients were not significantly different from controls. CONCLUSION: These data suggest that BAL differential cell counts may be a useful adjunct in the differential diagnosis of pulmonary infection in immunocompromised children.

Adolescent↗

PubMed2004

Molecular epidemiology of childhood mitochondrial encephalomyopathies in a Finnish population: sequence analysis of entire mtDNA of 17 children reveals heteroplasmic mutations in tRNAArg, tRNAGlu, and tRNALeu(UUR) genes.

OBJECTIVES: Many heteroplasmic point mutations in tRNA genes of mitochondrial DNA (mtDNA) have been associated with human diseases. We recently reported on a prospective 7-year study in which we enrolled 116 consecutive children with undefined encephalomyopathy. Seventeen of them were found to have both a defect in the mitochondrial respiratory chain and abnormal ultrastructure of muscle mitochondria, suggesting a clinically probable mitochondrial encephalopathy. METHODS: We determined the frequency of mtDNA mutations in these 17 children by analyzing the entire sequence of mtDNA by conformation-sensitive gel electrophoresis and sequencing. RESULTS: Three heteroplasmic tRNA mutations that were considered to be pathogenic were detected. Two of the mutations were novel transitions, 10438A>G in the tRNA(Arg) gene and 14696A>G in the tRNA(Glu) gene, whereas the third one was 3243A>G, the common MELAS mutation. The mutant load was very high in the blood and skeletal muscle of the patients and markedly lower in the blood of asymptomatic maternal relatives. The 10438A>G mutation changes the nucleotide flanking the anticodon, whereas 14696A>G changes a nucleotide in the stem of the pseudouridine loop, creating a novel base pair and reducing the wobble. CONCLUSIONS: Our results emphasize that the analysis of the entire sequence of mtDNA is worthwhile in the diagnostic evaluation of patients with clinically probable mitochondrial encephalomyopathy. The frequency of pathogenic mtDNA mutations was found to be 18% among children with biochemically and histologically defined mitochondrial disease, suggesting that the likelihood of nuclear DNA mutations in such a group is several times higher than that of mtDNA mutations.

Base Sequence↗

PubMed2002

[Changes of pathogenic bacteria in pediatric patients of septicemia and drug resistance there of in Zhejiang Children's Hospital 1991 approximately 2000].

OBJECTIVE: To investigate the changes of pathogenic bacteria detected from the blood culture of pediatric patients with septicemia in the past 10 years, and to observe the drug resistance thereof in the past two years. METHODS: The blood samples of 4 425 pediatric patients aged 0 approximately 14 with the diagnosis of septicemia 1991 approximately 2000 in Zhejiang Children's Hospital were cultured in broth (1991 approximately 1996) or VITA AER blood culture apparatus (1997 approximately 2000). Analytic Product Inc. (API ) system and KB paper strip method and VITEK automicroscan were used to identify the species and conduct drug resistance test. The results were interpreted according to the guideline of National Committee for Clinical Laboratory Standards. RESULTS: In the past 10 years, Gram-positive bacteria remained the more frequent pathogens than Gram-negative bacteria in pediatric patients with septicemia. The proportion of coagulase-negative staphylococcus (CNS) had been increasing and reached 69% in 2000. The proportions of Staphylococcus aureus and Escherichia coli decreased from 35.4% and 18.2% in 1991 to 5.3% and 1.5% in 2000. In the past two years, the drug resistance rate of staphylococci against penicillin and erythromycin were more than 90% and 70% respectively. The oxacillin resistance rate of CNS was 60.3%, significantly higher than that of Staphylococcus aureus (10.3%). No strain of Staphylococcus and Enterococcus resistant to vancomycin was found. Escherichia coli and Psudomonas aeruginosa and other species of Enterobacteriae were sensitive to imipenem/cilastin sodium, whereas the resistance rate of them to ampicillin and first generation cephalosporins was more than 50%. CONCLUSION: (1) Gram-positive bacteria are the predominant pathogens of pediatric patients with septicemia, with the species of Staphylococcus ranking first among which CNS is the main pathogen for infants and Staphylococcus aureus is the main pathogen for school children. (2) Escherichia coli is the most frequently found pathogenic Gram-negative bacterium in infants with septicemia whereas Salmonella in school children. (3) Drug resistance of isolated pathogenic bacteria in department of pediatrics is a serious problem. Monitoring the change of pathogen and the trends of antimicrobial resistance is very important in guiding therapy.

Adolescent↗

PubMed2005

Quantitative assessment of the effect of uracil-DNA glycosylase on amplicon DNA degradation and RNA amplification in reverse transcription-PCR.

Although PCR and RT-PCR provided a valuable approach for detection of pathogens, the high level of sensitivity of these assays also makes them prone to false positive results. In addition to cross-contamination with true positive samples, false positive results are also possible due to "carry-over" contamination of samples with amplicon DNA generated by previous reactions. To reduce this source of false positives, amplicon generated by reactions in which dUTP was substituted for dTTP can be degraded by uracil DNA glycosylase (UNG). UNG does not degrade RNA but will cleave contaminating uracil-containing DNA while leaving thymine-containing DNA intact. The availability of heat-labile UNG makes use of this approach feasible for RT-PCR. In this study, real-time RT-PCR was used to quantify UNG degradation of amplicon DNA and the effect of UNG on RNA detection. Using the manufacturers' recommended conditions, complete degradation of DNA was not observed for samples containing 250 copies of amplicon DNA. Doubling the UNG concentration resulted in degradation of the two lowest concentrations of DNA tested, but also resulted in an increase of 1.94 cycles in the CT for RNA detection. To improve DNA degradation while minimizing the effect on RNA detection, a series of time, temperature and enzyme concentrations were evaluated. Optimal conditions were found to be 0.25 U UNG per 25 microl reaction with a 20 min, 30 degrees C incubation prior to RT-PCR. Under these conditions, high concentrations of amplicon DNA could be degraded while the CT for RNA detection was increased by 1.2 cycles.

Arterivirus↗

PubMedDate not supplied

Production of pro- and anti-inflammatory cytokines of human placental trophoblasts in response to pathogenic bacteria.

OBJECTIVE: We studied the production of cytokines in purified cultures of human term trophoblasts in the presence of pathogenic strains of Escherichia coli, Bacteroides fragilis, Mycoplasma hominis, Staphylococcus aureus, and Streptococcus agalactiae, which have been identified in intrauterine infections. METHODS: Human villous trophoblasts were isolated from term placentas after cesarean section and purified by several steps. After 6, 12, and 24 hours of incubation with the different heat-inactivated bacteria, interleukin-1beta (IL-1beta), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-10 (IL-10) as well as tumor necrosis factor-alpha (TNF-alpha) were measured from supernatants by commercially available enzyme-linked immunosorbent assay. Expression of cytokine mRNAs was determined by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: In nonstimulated cultures, low (IL-1beta and TNF-alpha) and high (IL-6, IL-8, and IL-10) basal secretion of cytokines was detectable. The pathogenic microorganisms induced a dose- and time-dependent release of IL-1beta, IL-6, IL-8, and IL-10, whereas TNF-alpha secretion was not elevated. E coli was the most potent inducer followed by B fragilis, S agalactiae, S aureus, and M hominis. Transcripts encoding IL-1beta, IL-6, IL-8, or IL-10 were elevated in the RT-PCR reactions, suggesting that transcriptional mechanisms contribute to elevated cytokine expression. CONCLUSION: Pathogenic microorganisms stimulated mRNA expression and polypeptide release of pro- and anti-inflammatory cytokines from placental trophoblasts. Induction of both inflammation-promoting and inflammation-inhibiting cytokines by bacterial products could play a role in modulating the inflammatory response associated with chorioamnionitis.

Bacterial Infections↗

PubMed2005

A rapid and quantitative method for the detection of Leptospira species in human leptospirosis.

Prompt laboratory diagnosis of leptospirosis infection facilitates patient management and initiation of therapy. A cost effective real-time PCR assay using SYBR Green I was developed for detection of pathogenic leptospires in serum specimens. Specific PCR products were obtained only with DNA of pathogenic Leptospira genomospecies. LightCycler PCR ability to distinguish between species was possible using melting curves, providing an approach for identification with a specific Tm assigned to a single species or set of species. Assay sensitivity was approximately 50 leptospires/ml, corresponding to one to two genome copies in a PCR mixture. Fifty-one patients who had clinical symptoms consistent with leptospirosis were tested both with a previously described rrs amplification and our real-time assay. Our LFB1 real-time assay confirmed the diagnosis for 25 patients (49%, 25/51) and revealed an estimated density of 8.0x10(1)-3.9x10(4) leptospires/ml of blood. The total assay time for 12 clinical samples from sample to data analysis was less than 3 h. These data illustrate the potential of our LFB1 real-time assay for the rapid detection of leptospires in serum samples and their subsequent quantification in a single run.

Adolescent↗

PubMed1999

Characterization of porcine T lymphocytes and their immune response against viral antigens.

T lymphocytes play a central role in the antigen-specific immune response against various pathogens. To detect and to characterize porcine T lymphocytes, monoclonal antibodies (mAb) against leukocyte differentiation antigens had been raised and classified for their specificity. Analyses of porcine T lymphocytes with specific mAb against CD4 and CD8 differentiation antigens revealed differences in the composition of the porcine T-lymphocyte population compared to other species. In addition to the known subpopulations, CD4+CD8- T helper cells and CD4-CD8+ cytolytic T lymphocytes, extra-thymic CD4+CD8+ T lymphocytes and a substantial proportion of CD2-CD4-CD8- T cell receptor (TcR)-gamma delta+ T cells could be detected in swine. Functional analyses of porcine T-lymphocyte subpopulations revealed the existence of two T-helper cell fractions with the phenotype CD4+CD8- and CD4+CD8+. Both were reactive in primary immune responses in vitro, whereas only cells derived from the CD4+CD8+ T-helper-cell subpopulation were able to respond to recall antigen in a secondary immune response. With regard to T lymphocytes with cytolytic activities, two subsets within the CD4-CD8+ T-cell subpopulation could be defined by the expression of CD6 differentiation antigens: CD6- cells which showed spontaneous cytolytic activity and CD6+ MHC I-restricted cytolytic T lymphocytes including virus-specific cytolytic T lymphocytes. These results enable now a detailed view into the porcine T-cell population and the reactivity of specific T cells involved in the porcine immune response against pathogens. Furthermore this knowledge offers the possibility to investigate specific interactions of porcine T lymphocytes with virus-specific epitopes during vaccination and viral infections.

Animals↗

PubMedDate not supplied

[The interrelations of genital lesions-urinary tract infections in girls].

This investigation was aimed at emphasizing the importance of early detection and elimination of the favoring factors which associated with an adequate treatment of urinary tract infection (UTI) represent the only way to prevent the recurrences that with time might cause severe kidney dysfunctions. It is a retrospective study of 220 girls aged 1 month to 16 years referred in the interval 1993-1997 to Iaşi Polyclinic No. 1 for pediatric gynecological examination and diagnosed with urinary tract infection. The clinical and laboratory evaluations were directed at determining the site of UTI, the factors that favored the recurrences, and the effects on renal function. The following favoring factors were found: disorders of the genital tract (22.2%), constipation (11.6%), oxyuriasis (4.5%), urinary tract obstructions (5.9%). The genital tract disorders were represented by inflammation (70%) (vaginitis, vulvovaginitis) and malformations (30%) (labia minora fusion, imperforate hymen, etc). The specific inflammation (48.5%) was mycotic (41.1%), bacterial (29.3%), the same pathogen being detected both in urine and vaginal discharge, trichomonal (17.6%), and gonococcal (11.6%). The high rate of recurrence in some UTI cases has proved once again the important role played by the favoring factors (genital tract disorders, urinary tract obstruction, constipation) and suggested that the correction of these conditions should be the only reasonable way to prevent recurrences.

Adolescent↗