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V Brade

Publications and source records attributed to V Brade.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Antibacterial effectiveness of povidone-iodine (Betaisodona) against highly resistance gram positive organisms].

Antiseptics that are locally applicable gain in significance due to their reliable microbicidal effectiveness and especially due to the rising incidence of highly resistant bacteria. This is because systemically applied antibiotics are not sufficient in eradicating superficial mucodermal bacteria and locally applied antibiotics can cause new resistance rapidly. The aim of this study was to demonstrate the microbicidal effectiveness of Poly(1-vinyl-2-pyrrodlidon)-iodine (PVP-iodine) against ten genotypical different methicillin resistant Staphylococcus aureus-(MRSA-) and five Enterococcus faecium-strains in a quantitative suspension test. The effectiveness of PVP-iodine with protein load (0.2% and 2% albumin) was tested against three MRSA strains. Without any protein load best microbicidial activity (KRt-value > 5) was obtained with concentrations in the range between 1-10% of the original Betaisodona solution after 30s exposure time. With protein load (0.2% albumin) the optimum in microbicidal effectiveness shifts to concentrations > or = 10% Betaisodona solution referring to an exposure time of 30s. With a protein load up to 2% albumin and an exposure time of 30s the bactericidal activity of the undiluted Betaisodona solution is already satisfying, while the 10% solution is not active till an exposure time of 5 min. Summing up PVP-iodine is recommended as a local mucodermal antiseptic against highly resistant gram positives.

Anti-Infective Agents, Local↗
PubMed1997

Clonal heterogeneity, distribution, and pathogenicity of methicillin-resistant Staphylococcus aureus.

Four thousand eighty-eight Staphylococcus aureus isolates obtained from patients hospitalised in a university clinic and four community hospitals over a period of one year were screened for methicillin resistance. A resistance rate of 5% was detected among initial isolates. Distribution of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus showed an increased prevalence of MRSA in clinically significant specimens such as blood, central venous catheter tips, bronchial secretions, and wound secretions. Typing of 110 MRSA strains (initial isolates) by macrorestriction analysis of chromosomal DNA revealed 26 different genotypes that could be divided into five epidemic and 21 sporadic strains. More than 50% of all isolates belonged to one type that was confirmed to be closely related to the "southern-German" epidemic strain. Production of virulence factors such as enterotoxin A-D and toxic shock syndrome-toxin 1 among MRSA strains (initial isolates) occurred in ten of 26 different MRSA types. A strong correlation between genotype and toxin production was demonstrated.

Clone Cells↗
PubMed1997

Heterogeneity in the complement-dependent bacteriolysis within the species of Borrelia burgdorferi.

Sixteen Borrelia burgdorferi strains, including all three species, were compared in a colorimetric bactericidal assay for their ability to escape the complement-dependent bacteriolysis on incubation in normal human serum free of specific antibodies (NHS). The species B. afzelii was found to be serum resistant (EB1, EB3, FEM1, FEM2, Pko), whereas strains of the species B. garinii were found to be serum sensitive (1/B29, G1, G2, PSth, PBr, PTrob). Six strains, mainly B. burgdorferi sensu stricto, were only partially sensitive (Z25, 297, B31, PKa-I, PBi). All strains activated the complement cascade in NHS, whereas only four strains (G1, G2, PBr, PSth) could activate complement in the presence of EGTA-Mg. After complement activation, covalently bound C3 fragments (C3b, iC3b) were detected on serum-sensitive as well as serum-resistant borrelial strains. Heterogeneity, however, was observed between serum-resistant and serum-sensitive strains with respect to deposition of C6 and C9. Whereas serum-sensitive strains were strongly positive for C6 and C9 and were, therefore, killed by the terminal complement complex (TCC), serum-resistant strains were devoid of C6 and C9 on their cell surface. The serum resistance may, therefore, be due to an absent or only transient formation of TCC on the bacterial surface.

Bacteriolysis↗
PubMed1997

Role of quantitative cultures and microscopic examinations of endotracheal aspirates in the diagnosis of pulmonary infections in ventilated patients.

Endotracheal aspirates (EA) from 20 intubated patients in a surgical intensive care unit (mean ventilation time/patient = 16.5 days) were investigated serially by performing quantitative cultures using growth of 10(5) cfu/mL as a cut-off point. Microscopic examinations were made using Giemsa's stain for polymorphonuclear neutrophils (PMN). The spectrum of pathogens encountered was determined and compared with clinical data to distinguish colonization from infection of the lower respiratory tract. Out of 301 EA cultures, 156 (51.8%) were positive and 145 (48.2%) were below the cut-off point. Counts of PMN were significantly higher in samples which gave positive cultures. Seventy-five different bacterial strains were isolated (64% were Gram-negative bacilli). Seventeen patients (85%) were colonized with Gram-negative bacteria. Nine patients (45%) developed nosocomial pneumonia (NP), five (25%) had no signs of pneumonia, and six (30%) had an uncertain status. Main causative agents for NP were Pseudomonas aeruginosa, Enterobacteriaceae and Staphylococcus aureus. Quantitative EA cultures had a sensitivity of 81.5%, a specificity of 64.8%, a positive predictive value of 55% and a negative predictive value of 87%. Our results suggest that EA quantitative cultures (cut-off value 10(5) cfu/mL), species identification and microscopic examination of EA may help to differentiate tracheobronchial colonization and infection, especially when bronchoscopic techniques are not available.

Adult↗
PubMed1996

High- and low-level cytokine induction in human peripheral blood mononuclear cells by different Borrelia burgdorferi strains.

In this report we have compared the ability of 14 Borrelia burgdorferi sensu lato isolates to stimulate monocytes. From these isolates, all three human pathogen genospecies were represented. To determine the stimulatory activity of the different strains, interleukin-1 beta (IL-1 beta) was measured in the supernatant of monocyte cultures. This was achieved with borrelial strains in a ratio of 10 bacteria to 1 monocyte. In the majority of strains the stimulation induced a release of about 8000 pg/ml IL-1 beta, whereas four strains (B31, 297, EB3, 1/B29) induced more than 18,000 pg/ml IL-1 beta. We could, therefore, define two groups: low-level inductors and high-level inductors for IL-1 beta. The strains in the defined groups could not be ascribed to one distinct genospecies or a biological source. Further experiments confirmed the same differential release for tumor necrosis factor-alpha, but not for IL-6. Studies on IL-1 beta indicated that high- and low-level release of cytokine was due to differences in protein synthesis.

Borrelia burgdorferi Group↗
PubMed1996

Frequency, clonal heterogeneity and antibiotic resistance of methicillin-resistant Staphylococcus aureus (MRSA) isolated in 1992-1994.

Since 1992, the proportion of methicillin-resistant Staphylococcus aureus (MRSA) isolated from patients of the University Hospital of Frankfurt/Main and six community hospitals increased to a level of 11% and has remained constant during the following two years. MRSA and methicillin-sensitive Staphylococcus aureus (MSSA) were distributed equally among almost all specimens except blood. There was evidence of a diminished potency of MRSA to cause bacteremia. All MRSA strains were susceptible to glycopeptides and mupirocin. Resistance rates to other non-beta-lactam antibiotics were low for fusidic acid (7.1%), fosfocin (8.3%), amikacin (11.4%) and cotrimoxazole (18.3%) and high for gentamicin (90.7%), ofloxacin (94.3%) and erythromycin (95.5%). Among 378 MRSA strains originating from 180 individuals, macrorestriction analysis of chromosomal DNA revealed 39 different genotypes. These could be divided into 14 epidemic strains isolated from 155 patients and 25 sporadic strains isolated from single patients. As most of the sporadic strains emerged in close local proximity to epidemic strains, we suppose a horizontal genetic transfer from MRSA to MSSA leading to the appearance of novel MRSA genotypes. Upon repeated isolation of MRSA strains from the same individuals, resistance rates and genotypes remained stable. Resistance patterns of the non-beta-lactams correlated poorly with macrorestriction analysis, whereas several MRSA genotypes could be distinguished by particular MICs of methicillin.

Anti-Bacterial Agents↗
PubMed1995

[Postmortem diagnosis of tropical malaria].

Thirteen days after returning from a four week holiday in Kenya a 35-year-old man consulted his doctor complaining of feeling unwell. The doctor diagnosed influenza and gave him a sickness certificate for three days. Because the patient did not reappear at his workplace a search was made and he was found dead in his flat seven days after seeing his doctor. A medicolegal autopsy was performed two days after the estimated time of death. There was marked swelling of liver and spleen together with jaundice and "dirty grey" colouration of the viscera. Samples of heart blood and spleen puncture material were taken. Giemsa stained preparations (ordinary and thick blood smears) revealed numerous objects 1.2 to 1.5 microns in size with indistinct reddish blue staining, some of them arranged in rosettes reminiscent of schizonts. A few of them contained pigment. In material from the spleen there were masses of blackish-brown pigment. The malaria immunofluorescence test performed on serum gave a weakly positive titre of 1:40. The findings were considered enough to support a diagnosis of fulminant falciparum malaria, and this was confirmed by histological changes in various organs, notably the typical capillary blockages in the brain. Because of the popularity of long-haul tourism, cases of imported malaria are increasingly frequent and, in view of the insidiously progressive course of the disease, it should always be considered in the differential diagnosis. In cases of unexplained death, if there is any suspicion of malaria, blood should always be taken for appropriate investigations, in addition to blocks for histological examination.

Adult↗
PubMed1995

Epidemiology of penicillin-resistant Neisseria gonorrhoeae in Frankfurt, Germany.

In the present study 150 Neisseria gonorrhoeae strains from prostitutes in Frankfurt, Germany, were investigated for their in vitro susceptibility to eight antimicrobial agents by the agar dilution test. While 21.3% of gonococci were highly resistant to penicillin (MICs > or = 2 mg/l), 49.4% of the organisms were moderately sensitive (MICs = 0.125-0.5 mg/l) and only 29.3% of strains were fully susceptible to penicillin (MICs < or = 0.06 mg/l). No resistance to other antibiotics tested was observed, with the exception of doxycycline, to which overall resistance was 9.7%. Genotypic analysis of Neisseria gonorrhoeae by the restriction enzyme technique showed that most penicillin-resistant strains could be grouped into two main bacterial clones, whereas penicillin-susceptible isolates displayed a remarkable heterogeneity. This observation suggests that a restricted number of resistant Neisseria gonorrhoeae strains are likely to spread within the prostitute population of Frankfurt, Germany.

Female↗
PubMed1994

Evaluation of a passive hemagglutination assay as screening test and of a recombinant immunoblot as confirmatory test for serological diagnosis of Lyme disease.

In order to evaluate a commercially available passive hemagglutination assay (PHA) as a screening test for the diagnosis of Lyme disease, 173 sera were tested by PHA and the results compared with those obtained by an indirect immunofluorescence assay (IFA) and a conventional immunoblot using whole cell antigen (IB). Identical results were found by PHA and IFA in 80% of all cases. The sensitivity of the PHA was comparable to that of the IB (96%). However, confirmation of positive PHA results was necessary due to lack of specificity. A commercially available recombinant immunoblot (RIB) was compared to a conventional IB for its efficiency as a confirmatory assay. The rate of agreement was 86% of 64 sera tested positive or negative by IB. However, in order to obtain this high concordance of the RIB and IB, it was necessary to modify the RIB interpretation criteria of the manufacturer. Thus, screening of serum specimens by the PHA and confirmation of test results by the RIB appears to be a convenient test combination that allows the serological diagnosis of Lyme disease in most cases.

Fluorescent Antibody Technique↗
PubMed1994

Serological distinction between syphilis and Lyme borreliosis.

The serological distinction of an immune response to the agent of syphilis, Treponema (T.) pallidum, and Lyme disease borreliae is difficult due to the existence of cross-reacting antibodies. In this study, the immunoblot technique is used to compare the immune response of sera from patients with syphilis or Lyme borreliosis to either T. pallidum or Borrelia (B.) burgdorferi. Patients with syphilis showed an IgG response to the 17 and 15 kDa antigens of T. pallidum, whereas sera from patients with Lyme borreliosis-especially in late stages of the disease-reacted with the 95 and 19-17 kDa antigens of B. burgdorferi. Thus, IgG antibodies against low molecular weight antigens of T. pallidum (17, 15 kDa) or B. burgdorferi (19-17 kDa) may represent useful markers for the serological diagnosis of syphilis or Lyme borreliosis.

Antibodies, Bacterial↗
PubMed1994

[Have the incidence and resistance of tuberculosis increased? Epidemiologic follow-up based on diseases confirmed by culture].

The unexpected increase in the incidence of tuberculosis in many industrialized countries, which was recorded in Germany for the first time in 1992, provided the incentive for this retrospective analysis over the past 13 years of the epidemiology and resistance situation for Tbc in the Rhine/Main area. Basis for the evaluation were the data from our laboratory which is the only institution in the region performing type and resistance determinations on mycobacteria. During the period of the investigation, in which 3,738 tuberculoses were confirmed in cultures, the number of cases of the disease among German citizens decreased continuously. However, the still stagnating incidence rates can probably be attributed to the increasing flow of immigrants from countries with a high Tbc prevalence. Extrapulmonary manifestations were detected more often among foreigners than among Germans (19.6% versus 13.3%, p < 0.0001). In 9.5% of the cases, resistance against at least one of the five primordial antituberculosis agents (INH, SM, EMB, RMP, and PZA) was observed; but the rate was almost twice as high among foreigners as among Germans (13.8% versus 7.4%, p < 0.001). An increase in resistance either against individual substances or in regard to combination resistance could not be observed. In spite of the relatively high number of HIV-positive persons in the Frankfurt region, HIV-associated tuberculosis is still too seldom to make a noticeable impression on the total incidence. In the light of the regional incidence and resistance rates determined by us, a special position or even pace-setting function of our conurbation within the epidemiological tuberculosis situation in Germany cannot be recognized at present.

AIDS-Related Opportunistic Infections↗
PubMed1993

[Tick bite and Lyme borreliosis. An epidemiologic study in the Erlangen area].

BACKGROUND: Lyme borreliosis is transmitted by tick bites. Approximately every fifth local tick (Ixodes ricinus) is infected. Transmission, therefore does not occur with every bite, and disease doesn't always follow infection. The goal of the study was to investigate the risks of infection and disease after tick bites in the area of Erlangen/Germany. METHODS: Between April 1989 and October 1991 seventy-one of our out-patients (30 females, 41 males) aged 6 months to 29 years had a tick bite and were enrolled into the study. After the ticks had been removed, a blood specimen for a specific Borrelia burgdorferi antibody assay (IFT) was collected. An interview by phone was performed 4 weeks later and an appointment for a second blood collection was arranged. RESULTS: In 69 patients the initial titer was negative, in two patients it was 1:32. Sixty patients could be reached by phone, and in 43 a second blood sample was available. There was seroconversion detectable in 4 instances, two of whom were asymptomatic, one had unspecific symptoms and one developed lymphocytoma. There were no manifestations of late stage disease in the study population. CONCLUSION: These results confirm the current recommendation of the Bundesgesundheitsamt (German Federal Health Institute) that generally antibiotic treatment after a tick bite is not necessary.

Adolescent↗
PubMed1992

Differences of two Borrelia burgdorferi strains in complement activation and serum resistance.

Complement activation and serum resistance of the Borrelia burgdorferi strains B31 (American strain) and PKo (European strain) were compared. In 25% (v/v) normal human serum (NHS) free of B. burgdorferi-specific antibodies the cells of the PKo strain were high activators of complement as indicated by rapid and strong C9 consumption, by deposition of up to 336763 C9 molecules per cell and by the formation of the terminal complement complex on the cell surface. By comparison, complement activation by the B31 strain was low with 5.4-fold less C9 deposited per cell. The addition of B. burgdorferi-specific antibodies to NHS either as purified IgG or heat-inactivated patient sera, had no influence on the results with both strains. After an incubation period of 2h at 37 degrees C in 25% (v/v) NHS most cells of the PKo strain had lost their viability as indicated by cell immobilization and failure to multiply in subcultures. In addition, extensive cell fragmentation and bleb formation were observed in the electron microscope. In contrast, the B31 strain remained alive and morphologically intact after the same incubation with NHS. We conclude from our results that complement activation and serum resistance are properties which differ considerably between isolated strains of B. burgdorferi.

Antibodies, Bacterial↗
PubMed1992

Mechanism of YadA-mediated serum resistance of Yersinia enterocolitica serotype O3.

Complement activation via the alternative pathway was analyzed with isogenic strains of Yersinia enterocolitica serotype O3 differing in plasmid content (p- or p+ strains) or selective lack of YadA expression (YadA- strain). The p+ strain was serum resistant, even after antibody-enhanced complement activation. Serum sensitivity was observed with the p- and YadA- strains but was more pronounced in the p- strain. The p+ strain deposited less C5b-9(m) complexes on its surface than the p- and YadA- strains. No size difference, however, was detected with solubilized C5b-9(m) complexes obtained from resistant and sensitive strains. At the C3 level, it became evident that surface-bound C3b was degraded faster into iC3b on the p+ strain than on the p- and YadA- strains. Our results demonstrate that YadA inhibits complement activation at the C3 and C9 level. As a result, reduced amounts of C5b-9(m) are generated on the surface of YadA-bearing bacteria. In addition, YadA seems to protect against the lytic action of those C5b-9(m) complexes whose deposition could not be prevented.

Adhesins, Bacterial↗
PubMed1991

T cell proliferation induced by Borrelia burgdorferi in patients with Lyme borreliosis. Autologous serum required for optimum stimulation.

The cellular immune response to Borrelia burgdorferi was studied in 24 patients with seropositive and seronegative Lyme borreliosis, 30 patients with arthritides of different origin (non-Lyme arthritides), and 20 normal blood donors. By far, the strongest T cell stimulation was induced by incubation with autologous serum; there was a significantly lower response or no response after incubation with allogeneic or heterologous sera. In patients with Lyme borreliosis, including seronegative patients, there was a strikingly elevated proliferation in response to whole B burgdorferi bacteria (mean 64,750 dpm) compared with that of normal donors (mean 19,700 dpm; P less than 0.0001) and especially that of non-Lyme arthritis patients (mean 11,600 dpm; P less than 0.0001). Levels of proliferation declined significantly in patients with Lyme borreliosis after successful antibiotic treatment. Parallel cultures using B burgdorferi and Treponema phagedenis as antigens showed that cells from patients with Lyme borreliosis responded significantly more to B burgdorferi than to T phagedenis, but this did not occur with cells from individuals with non-Lyme arthritides. There was no correlation between disease stages and proliferation values. These data indicate that lymphocyte proliferation assays may provide an important tool for the diagnosis of Lyme borreliosis, most notably in patients with arthritides and in those who are seronegative. Conversely, the lack of reactivity appears to be a strong indicator of the absence of active Lyme disease. It seems to be crucial, however, to use autologous sera in these assays.

Adolescent↗
PubMed1991

Evasion of Yersinia enterocolitica serotype 03 from complement-mediated killing.

Using isogenic strains of Y. enterocolitica serotype 03 (isolate 75) differing in LPS side chains (S and R), plasmid content (p+ and p-) or selective failure of YOP1 expression (YOP1-) we observed comparable C9 consumption via the alternative pathway by all strains. Differences became apparent in the bactericidal assays in which the 75S p+ strain was resistant whereas the plasmid-negative S and R strains were killed. Increased but submaximal resistance was observed with the 75R p+ and 75S YOP1- strains indicating that LPS side chains and plasmid-encoded factors other than YOP1 also contribute to serum resistance. Deposition of C9 and terminal complement complex (TCC) formation were greatly reduced on the resistant 75S p+ strain compared to the sensitive 75S p- strain. The 75S YOP1- variant behaved like the 75S p- strain with respect to C9 deposition and TCC formation suggesting that YOP1 prevents terminal C activation. A comparison of TCC deposited on resistant and sensitive Y. enterocolitica revealed no differences with respect to their salt- and protease-resistance and their size. We conclude from our experiments that serum resistance of 75S p+ depends on several surface components YOP1 being the most important. The YOP1 protein clearly interferes with C9 deposition and TCC formation and thereby contributes to serum resistance of plasmid-positive, YOP1 expressing Y. enterocolitica.

Centrifugation, Density Gradient↗
PubMed1990

[Fatal pneumococcal meningitis in a 1-year-old child with homozygous C2 deficiency].

The 1-year old girl died of recurrent bacterial meningitis. Streptococcus pneumoniae was isolated from the cerebrospinal fluid. The analysis of the immune system revealed only a defect of the complement system. The following results were obtained: 1. No function of the classical complement pathway. 2. Reduced function of the alternative complement pathway. 3. No functional C2 activity. 4. No C2 protein. The parents had half normal C2 titers. HLA typing was only possible for the parents with the following results: A1, A32(w19), B18, DR2, DRw11(5) (father) and A3, A10, B18, B7, DR2 (mother). These data are compatible with a B18, DR2 haplotype of the child which is found in most cases of homozygous C2 deficiency. Our patient list another example for the high risk of recurrent severe infectious diseases in persons with a total complement defect.

Complement C2↗