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A Schwarzkopf

Publications and source records attributed to A Schwarzkopf.

At least 19 recordsLinked to original sources
PubMed2002

[Medicine behind bars. Illness is usual not grounds for modifying imprisonment].

The article describes the possibilities of medical care in prison as exemplified by the Kassel 1 prison with its attached central hospital facility. The main areas of medical care covered there are the treatment of wounds, conservative treatment of fractures, ophthalmology, ENT, urology, dentistry and, via external consultant physicians, also internal medicine, pneumology, dermatology and gynecology. Such infections as hepatitis B and C, syphilis, and tuberculosis have a greater prevalence among prisoners--in contrast to other infections afflicting people housed under similar living conditions, such as in communal living facilities, which show no such increased prevalence. Furthermore, there is a relatively high percentage of injuries, including those that are self-inflicted. The problem of certifying a prisoner medically unfit to tolerate imprisonment is discussed.

Adult↗
PubMed2001

Role of vascular remodeling in the pathogenesis of early transplant coronary artery disease: a multicenter prospective intravascular ultrasound study.

BACKGROUND: Luminal narrowing in transplant coronary artery disease is thought to be primarily caused by intimal proliferation, and the role of vascular remodeling is less certain. METHODS AND RESULTS: We studied cardiac allografts from 83 prospectively recruited patients immediately and 1 year after transplant using intravascular ultrasound in a multicenter study. We measured coronary artery dimensions in 310 angiographically matched segments (175 were also fully matched by ultrasound criteria). At 1 year, lumen area changed by -1.8 +/- 3.7 mm(2) (p < 0.0001, 14% of baseline lumen area). Thirty-three percent of this luminal loss was due to intimal thickening and 67% to vessel shrinkage. Shrinkage also occurred (-0.9 +/- 3.2 mm(2), 7% of baseline total area) in segments free of detectable intimal disease at baseline and at 1 year. Using the mean baseline total vessel area (13.9 mm(2)) as the cutoff, we divided the cohort into the large and the small coronary-segment groups. The large-segment group (n = 176) shrank more (-2.6 +/- 4.4 vs. -0.03 +/- 2.8 mm(2), p < 0.0001), but intimal growth was similar in both groups (0.8 +/- 2.2 vs. 0.4 +/- 1.3 mm(2), p = not significant). Analysis of the 175 fully ultrasound matched sub-cohort showed similar results. Changes in intimal area, total vessel area, and lumen area were similar in segments with (n = 132) and segments without (n = 178) pre-existing donor disease. Despite overall shrinkage, change in total vessel area positively correlated with change in intimal area (r = 0.29, p < 0.0001). CONCLUSION: In large coronary segments, coronary artery shrinkage plays an important role in the loss of luminal diameter early after cardiac transplantation, whereas new intimal growth occurs in both large and small segments. Pre-existent donor disease does not aggravate these processes. Compensatory remodeling with increasing intimal growth retards the rate of lumen loss. As is intimal thickening, shrinkage and compensatory remodeling are important pathogenic mechanisms in transplant coronary artery disease.

Adult↗
PubMed2000

Determinants of coronary remodeling in transplant coronary disease: a simultaneous intravascular ultrasound and Doppler flow study.

BACKGROUND: Coronary remodeling plays a significant role in lumen loss in transplant allograft vasculopathy (TxCAD), but the determinants of remodeling are unknown. We assessed the relationship between remodeling and plaque topography, coronary compliance, and blood flow in TxCAD. METHODS AND RESULTS: One artery in each of 27 transplant patients was investigated with simultaneous intravascular ultrasound and coronary flow measurements (basal and hyperemic by Doppler flow wire). At 4 to 8 different cross sections (mean 5.1+/-1. 2), plaque topography (concentric or eccentric) was determined, and total vessel area, lumen area, and intimal/medial area (IMA) were measured. Mean remodeling ratio (vessel area/IMA) in eccentric lesions (E, n=28) was significantly larger than that in concentric lesions (C, n=70) (E 5.87+/-0.93 versus C 3.58+/-0.62; P<0.001), despite similar IMA (E 3.89+/-0.68 versus C 3.90+/-0.41; P=NS) and distribution of imaged segments. Remodeling ratio was consistently larger in eccentric lesions in all 3 vessel segments when analyzed separately, and mean remodeling ratio for each artery was larger in vessels with predominantly eccentric lesions. Coronary compliance ([Delta lumen area/diastolic lumen area]/Delta mean arterial pressure x 10(3)) was also significantly greater in eccentric lesions versus concentric lesions (proximal 1.00+/-0.39 versus 0.22+/-0.04; mid 0.71+/-0.17 versus 0.21+/-0.10; distal 0.43+/-0.13 versus 0. 01+/-0.08; all P<0.01). Coronary flow reserve was also significantly higher in coronary arteries with primarily eccentric lesions (E 2. 49+/-0.64 versus C 1.87+/-0.28; P<0.01). CONCLUSIONS: Vessel remodeling in transplant vasculopathy is significantly greater in eccentric lesions than in concentric lesions, possibly due to greater coronary compliance and resistive vessel function.

Compliance↗
PubMed1999

[Modification of bacterial growth by alloplastic bone substitutes].

BACKGROUND: To determine the applicability of alloplastic materials as bone substitutes it is now standard procedure to test materials for possible toxic effects and to study their behavior in animal models and cell cultures. This is especially important with respect to middle ear implants that can be put at risk by recurrent infections and require additional testing in a bacterially contaminated environment. MATERIALS AND METHODS: In the present study ionomeric cement (V-O CEM), bioactive glass ceramic and hydroxyapatite were subjected to contamination with S. aureus, E. coli, Pr. mirabilis, Ps. aeruginosa and Enterococci using agar diffusion and microbial suspension tests and examined for their antibacterial activity. A special feature of V-O CEM that had to be considered was that it could be implanted in two physical states (as a viscous substance and a fully hardened material). RESULTS: The agar diffusion test showed that an antibacterial effect of freshly mixed V-O CEM was demonstrable for up to 60 min. In the microbial suspension test growth of E. coli was found to be promoted after 48-h incubation by V-O CEM set for 1 h. S. aureus exhibited a depressed growth, while Pseudomonas cultures demonstrated cell death after 48 h. V-O CEM set for 24 h and 7 days, respectively, exerted a similar though less pronounced effect. Using the microbial suspension test, a comparison was also made of the antibacterial activities of 24-h V-O CEM, bioactive glass ceramic and hydroxyapatite against cultures of S. aureus, Pseudomonas and E. coli. The inhibitory effect of hydroxyapatite on the growth of S. aureus was found to persist beyond the 48-h incubation period. There was slight growth of E. coli in the presence of bioactive glass ceramic after 48 h, whereas hydroxyapatite produced inhibition of microbial growth. V-O CEM inhibited the growth of Pseudomonas, unlike bioactive glass ceramic and hydroxyapatite, which transiently promoted bacterial growth. DISCUSSION AND CONCLUSIONS: Our findings showed that V-O CEM, bioactive glass ceramic and hydroxyapatite exhibited material-dependent bacterial colonization and thus resembled polymeric bone substitutes (susceptible to invasion by S. epidermidis) and metals (sensitive to S. aureus). In general, users of bone substitutes should conduct preclinical tests in order to obtain advance information on the properties of possible replacement material. Since there can be varying interactions between the materials studied and bacterial growth, material-specific effects on bacterial growth should be investigated. While it is recognized that in vitro studies are an inadequate simulation of the clinical situation, they still provide some insight into the likely behavior of a bone substitutes in human sites.

Bacteriological Techniques↗
PubMed1999

Influence of different autotransfusion devices on the quality of salvaged blood.

BACKGROUND: Cardiopulmonary bypass causes a systemic inflammatory response and impaired hemostasis. We investigated whether intraoperative blood salvage with the cardiotomy suction contributes to these alterations. Furthermore, an alternative autotransfusion device (Haemonetics cell-saving device) was examined. METHODS: In 10 patients, interleukin-6, interleukin-8, tumor necrosis factor-alpha, thrombin-antithrombin complex, plasmin-antiplasmin complex, free hemoglobin, and the percentage of CD62+ thrombocytes were determined in the systemic circulation during cardiopulmonary bypass, in the cardiotomy suction tube, and in the blood from the cell-saving device. Additionally, bacterial contamination was examined. RESULTS: Median levels of interleukin-6 (52 versus 10 microg/L; p = 0.005), interleukin-8 (26 versus 20 microg/L; p = 0.017), tumor necrosis factor-alpha (24 versus 1 microg/L; p = 0.005), thrombin-antithrombin complex (113 versus 43 microg/L; p = 0.005), plasmin-antiplasmin complex (566 versus 489 microg/L; p = 0.022), and free hemoglobin (61 versus 30 mg/dL; p = 0.005) were higher in the cardiotomy suction tube compared with the systemic circulation. After processing the blood from the cell-saving device, interleukin-8, thrombin-antithrombin complex, and free hemoglobin remained above reference range, and in 90% of the cases bacterial contamination was observed. CONCLUSIONS: Cardiotomy suction additionally contributes to the release of proinflammatory cytokines, activation of coagulation, and hemolysis. Because blood salvage with a Haemonetics cell-saving device led to normalization of some, but not all, parameters and bacterial contamination was common, the alternative use seems at least questionable.

Adult↗
PubMed1997

The challenge of postoperative infections: does the surgeon make a difference?

Postoperative infections remain a challenge in many surgical procedures despite improved surgical technique and powerful antibiotics. The number of sepsis cases has tripled from 1979 to 1992 due to increased invasive procedures in older and immune-suppressed patients. Increasingly, in recent years, outbreaks of resistant pathogens have been published, provoking the question of how postoperative infections and resistant pathogens should be dealt with. Wound classification and risk stratification were developed to identify patients at risk for postoperative infection. However, other important intrinsic factors of the patient were not included, and further attempts have been made to increase sensitivity and specificity (eg, Study on the Efficacy of Nosocomial Infection Control project, National Nosocomial Infection Surveillance System score); the American Society of Anesthesiologists preoperative assessment score and the operation duration for specific procedures were introduced into the system as risk stratifiers. Advances in immunology have identified new ways in which the surgeon can moderate the immune response (eg, hemorrhage and blood transfusion-induced immune suppression). The increased rate of resistance in enterococci and staphylococci has refocused attention on infection control in surgery. However, there are recent reports from both sides of the Atlantic indicating that guidelines for infection control and antibiotic policy have not become reflected in standard procedures in many hospitals. New antibiotics may be developed, but resistance soon may follow. Sound techniques in surgery, with careful infection control and antibiotic policies, may be the only strategy to prevent further increases in resistance of pathogens in postoperative infections.

Antibiotic Prophylaxis↗
PubMed1996

Listeria monocytogenes--aspects of pathogenicity.

The genus Listeria includes different species of ubiquitary present gram-positive rod shaped bacteria. The species Listeria monocytogenes causes severe diseases like meningitis and meningoencephalitis in humans. Additional groups of syndromes associated with this microorganism are the listeriosis of the pregnant woman, mostly appearing as an abortion or septic premature birth and the meningitis of the newborn. Transmission of Listeria may occur on the oral route due to infected food like raw milk and cheese, raw meat or soil contaminated food like prepacked salads, respectively. The understanding of Listeria virulence was improved by different investigations employing cell cultures and molecular methods like knockout of genes encoding potential virulence factors. Nowadays the procedure of infection of cells is divided in four different parts: internalisation, escape from intracellular vacuole, nucleation of actin filaments and cell-to-cell spread. So called Internalins are produced by Listeria and are obviously needed for cell invasion. Listeria could escape intracellular vacuoles producing a hemolysin, Listeriolysin O, and proliferate inside the host cells. The surface bounded protein Actin A mediates the contact to the actin filament system of the host cell. This is important for the intracellular spread of Listeria. In the next step a cell-to-cell spread supported by phospholipase and lecithinase occurs. Despite the high incidence of contaminated food only a little incidence of listeriosis is observed. This may be explained in an indirect vaccination due to less virulent strains. However, the immune response of patients even with well documented listeriosis may be poor and causes false negative serological results sometimes. In this paper the know virulence factors of the interesting species L. monocytogenes are demonstrated and the course of infection is discussed.

Female↗
PubMed1995

Bactericidal properties of Campylobacter jejuni-specific immunoglobulin M antibodies in commercial immunoglobulin preparations.

Campylobacter jejuni is one of the most common enterocolitis-causing microorganisms worldwide. It is of particular importance in immunodeficient patients, who frequently are prone to develop extraintestinal manifestations. Since these cases respond poorly to antibiotic treatment, a supportive immunomodulating therapy including the administration of C. jejuni-specific immunoglobulins would be desirable. In the present study, nine commercial immunoglobulin preparations for intravenous use were tested for the presence of C. jejuni lipopolysaccharide (LPS)- and outer membrane protein (OMP)-specific antibodies by using immunoblot and enzyme-linked immunosorbent assay techniques. The immunoglobulin G (IgG) antibody reactivities against these antigens were comparable in eight of nine tested immunoglobulin preparations. Only in one preparation were C. jejuni OMP- and LPS-specific IgM antibodies found. In this preparation the immunoblot test revealed a strong reactivity against both flagellin and a major OMP. Moreover, all immunoglobulin preparations recognized OMPs of C. jejuni serotypes Lior 4, 9, 11, and 29 equally strongly, while the reactivity to an anti-Lior 36 isolate was less marked. Furthermore, the bactericidal properties of three immunoglobulin preparations were tested by means of chemiluminescence signaling in and bacterial killing by human polymorphonuclear leukocytes (PMNL). The results show that the IgM preparation enhanced Campylobacter-triggered chemiluminescence signaling in PMNL as well as killing of C. jejuni by PMNL, while the other immunoglobulin preparations did not do so. These results suggest that the administration of immunoglobulin preparations containing C. jejuni-specific IgM antibodies would be beneficial for patients with severe C. jejuni infections.

Antibodies, Bacterial↗
PubMed1995

Long-term shedding and clonal turnover of enterohemorrhagic Escherichia coli O157 in diarrheal diseases.

To investigate the length of time that Shiga-like toxin-producing Escherichia coli O157 is excreted after the onset of diarrhea, 456 serial stool specimens were obtained from 53 children. E. coli O157 cells were identified by the use of DNA probes followed by agglutination with a specific antiserum. Specimens were collected until three consecutive stool samples (collected within 9 days) were negative for E. coli O157. The median durations of shedding were 13 days (range, 2 to 62 days) in patients with diarrhea or hemorrhagic colitis and 21 days (range, 5 to 124 days) in patients that developed hemolytic uremic syndrome. In 36 (68%) of the patients, only the first culture was O157 positive, and the three cultures that followed were negative. In 7 (13%) of the patients, E. coli O157 cells were shed for more than 32 days after the onset of diarrhea; these long-term shedders were clinically asymptomatic by the end of this period. In 12 patients, one or two serial O157-negative cultures, obtained up to 8 days after a positive culture, were followed by another positive culture. Comparison of the first and last E. coli O157 isolates by pulsed-field gel electrophoresis revealed that in three of the seven long-term shedders, pulsed-field gel electrophoresis types varied. In two cases, a Shiga-like toxin gene was apparently lost during infection. The observation of long-term shedding accompanied by genotypic turnover has epidemiological and diagnostic implications.

Bacterial Toxins↗
PubMed1995

[Coagulase gene polymorphism in Staphylococcus aureus--a new epidemiologic marker].

Nosocomial infections with Staphylococcus aureus necessitate the prompt recognition of the infectious chain as well as a rapid investigation and exclusion of infectious sources. Conventional typification procedures (e.g. phage typing) and genotyping methods with pulsed-field gel electrophoresis (PFGE) are labor-intensive and time-consuming and can be performed only in a few laboratories. A new attractive typing technique for S. aureus utilizes the polymorphism of the coagulase (coa) gene as an epidemiological marker. This typing method is performed with primers, homologous to a conserved region within the coa gene, in order to amplify the sequences encoding the C-terminal region of this molecule. Since the number of repetitive sequences varies within the coa gene, the resulting PCR products of individual strains can be of different lengths. We have assessed the coa gene length polymorphism in 150 strains of S. aureus. By the sizes of the PCR products these strains could be categorized into 10 subgroups. AluI restriction analysis of the PCR products resulted in a significantly higher degree of discrimination. Since the repeated sequences, consisting of 81 base pairs, possess a high variability of the nucleotides, a characteristic restriction fragment length polymorphism (coa-RFLP) pattern is yielded. Overall, we could distinguish 64% of the clinical isolates by RFLP analysis; in strains sharing identical antibiograms, 56% could be distinguished. 46% oxacillin-resistant strains, some of which originated from epidemic outbreaks, could be discriminated by their RFLP pattern. Comparing these results with those obtained from the PFGE method, isolates which differed by their coagulase gene RFLP also differed by their PFGE patterns.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteriophage Typing↗
PubMed1994

Differentiation in virulence patterns of Escherichia coli possessing eae genes.

In this study 98 Escherichia coli strains which belonged to traditional enteropathogenic (EPEC) serotypes and 82 enterohemorrhagic E. coli (EHEC) strains were screened by polymerase chain reaction (PCR) for the presence of E. coli-attaching and -effacing (eae) genes. These strains were also hybridized with the enteropathogenic adherence factor (EAF) probe and examined in the fluorescence actin staining (FAS) test. The results obtained from the individual strains demonstrated that all 26 class I EPEC with localized adherence to HEp-2 cells carried EAF and eae genes. In contrast, of 72 EPEC strains with no or diffuse adherence only 1 strain was EAF positive and 6 strains had eae. Of 82 EHEC strains a total of 75 carried eae sequences. Of considerable interest, 15 of 21 E. coli strains that lost their slt genes during subcultivation were found to be eae positive. As controls a total of 53 enterotoxigenic and enteroinvasive E. coli, and 125 E. coli strains from the normal flora were investigated and all displayed negative results in the eae-PCR. From the 201 strains comprising classical EPEC serotypes, EHEC and E. coli with lost slt genes, a total of 126 displayed a positive FAS test and 122 reacted in the eae-PCR. Only 4 strains were FAS test positive but eae-PCR negative. Our data indicate that E. coli strains possessing the eae genes are heterogenous with respect to their virulence determinants. Loss of virulence plasmids and phage-encoded slt genes either in the host or during storage may contribute to this heterogeneity. The eae-PCR detected all class I EPEC and 91.5% of the EHEC.(ABSTRACT TRUNCATED AT 250 WORDS)

Adhesins, Bacterial↗
PubMed1994

Prevalence of attaching and effacing Escherichia coli in stool samples from patients and controls.

Enteropathogenic E. coli (EPEC) and enterohemorrhagic E. coli (EHEC) have the ability to cause 'attaching and effacing' (AE) lesions; the genes necessary to cause AE in both of these pathogroups have been identified and termed eae. Using colony hybridization, we screened 237 stool samples from patients with diarrhea, and 237 stool samples from age-matched controls for the presence of E. coli carrying eae. Individual colonies harbouring eae could be recovered from 7 (2.9%) of the patient stools, as well as from 6 (2.5%) of the control stools. All these E. coli isolates were positive in the fluorescence actin staining (FAS) test. In addition, all the samples were also probed for Shiga-like toxin (slt) genes and the EPEC adherence factor (EAF) to evaluate whether testing for eae identified all EHEC and class I EPEC. Of the 7 patient samples harbouring E. coli with eae, 4 had E. coli with eae and slt genes, and 2 had E. coli with eae and EAF sequences. In 2 of the 237 patient stools, E. coli which were eae and EAF negative but slt probe positive could be recovered. These 2 E. coli strains were non-reactive in the FAS test. Of the control samples, none of the E. coli strains, including the 6 samples containing eae positive strains, possessed EAF or slt-sequences. In concrete terms, the similar eae incidence found in both E. coli isolates from patients and controls is currently of limited clinical diagnostic value and more importantly, the eae probe could not identify all slt-harbouring E. coli. On the basis of these results, the use of the eae-probe cannot be recommended in preference to the slt probes for the detection of EHEC.

Adhesins, Bacterial↗
PubMed1994

DNA fingerprinting of Eikenella corrodens by pulsed-field gel electrophoresis.

In order to conduct molecular typing of Eikenella corrodens strains by macrorestriction fingerprinting, we evaluated different restriction enzymes for digestion of genomic DNA and determined the optimal parameters for separating E. corrodens DNA by pulsed-field gel electrophoresis. Ten E. corrodens strains isolated from oral and extraoral infection sites in different individuals were analyzed. The rare-cutting restriction endonucleases DraI, SmaI and XbaI usually used for pulsed-field gel electrophoresis analyses were not suitable for digestion of E. corrodens genomic DNA because they either did not digest the DNA or produced bands of similar molecular weights that could not be separated. Accordingly, among additional enzymes including BamHI, BglII, EcoRI and Hind III, we found BamHI and BglII to be the most suitable rare-cutting enzymes for pulsed-field gel electrophoresis analysis. They cleaved the genomes of all the above strains into 15-20 fragment bands that were clearly separated by the following pulsed-field gel electrophoresis conditions: 140 V with a running time of 40 h, pulse times of 5 to 50 s with linear ramping and an electrical field angle of 120 degrees. These conditions enabled us to distinguish 8 individual pulsed-field gel electrophoresis patterns from the 10 strains analyzed. However, only 4 identical outer membrane protein profiles were differentiated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The data obtained in this analysis showed clonal divergence among members of the E. corrodens species, at the same time revealing this pulsed-field gel electrophoresis as being a highly attractive procedure for epidemiological investigation of this organism, including its acquisition and transmission.

Bacterial Outer Membrane Proteins↗
PubMed1994

Characterization of transposon mutants of biofilm-producing Staphylococcus epidermidis impaired in the accumulative phase of biofilm production: genetic identification of a hexosamine-containing polysaccharide intercellular adhesin.

The primary attachment to polymer surfaces followed by accumulation in multilayered cell clusters leads to production of Staphylococcus epidermidis biofilms, which are thought to contribute to virulence in biomaterial-related infections. We isolated Tn917 transposon mutants of biofilm-producing S. epidermidis 13-1, which were completely biofilm negative. In pulsed-field gel electrophoresis no obvious deletions of the mutants were noted. The Tn917 insertions of mutants M10 and M11 were located on different EcoRI fragments but on identical 60-kb SmaI and 17-kb BamHI chromosomal fragments. Linkage of transposon insertions of mutants M10 and M11 with the altered phenotype was demonstrated by phage transduction, whereas the several other mutants apparently represented spontaneous variants. In a primary attachment assay with polystyrene spheres, no significant difference between any of the mutants and the wild type could be detected. Cell clustering as an indication of intercellular adhesion, which is a prerequisite for accumulation in multilayered cell clusters, was not detected with any mutant. These results demonstrate that the mutants were impaired in the accumulative phase of biofilm production. Mutants M10 and M11 did not produce detectable amounts of a specific polysaccharide antigen (D. Mack, N. Siemssen, and R. Laufs, Infect. Immun. 60:2048-2057, 1992), whereas substantially reduced amounts of antigen were produced by the spontaneous variants. Hexosamine was determined as the major specific component of the antigen enriched by gel filtration of biofilm-producing S. epidermidis 1457 because almost no hexosamine was detected in material prepared from the isogenic biofilm-negative transductant 1457-M11, which differentiates the antigen from other S. epidermidis polysaccharide components. Our results provide direct genetic evidence for a function of the antigen in the accumulative phase of biofilm production by S. epidermidis by mediating intercellular adhesion.

Antigens, Bacterial↗
PubMed1994

Genetic variation in Staphylococcus aureus coagulase genes: potential and limits for use as epidemiological marker.

To perform coagulase gene typing, the repeated units encoding hypervariable regions of the Staphylococcus aureus coagulase gene were amplified by the PCR technique; this was followed by AluI restriction enzyme digestion and analysis of restriction fragment length polymorphism (RFLP) patterns. In order to assess the discriminatory power of this typing method, 30 epidemiologically unrelated S. aureus strains which differed by their pulsed-field gel electrophoresis patterns were examined. Although 18 of the 30 strains had unique and unshared AluI RFLP patterns, there were only four observed patterns in the remaining 12 strains. This finding indicated that unrelated strains may share identical AluI RFLP patterns. To elucidate the degree of genetic variation in the C-terminus-encoding loci within the coagulase genes, the PCR products of these 12 strains were subjected to Taq polymerase-mediated sequencing. Sequence analysis confirmed the AluI recognition sites in each of the four RFLP groups and demonstrated that AluI appears to yield the highest RFLP in restriction enzyme analysis. By their DNA sequences the majority of strains sharing common AluI groups could be clearly differentiated from each other and revealed between 93.2 and 98.5% homology. When we determined the nucleotide sequences of two strains after six subcultivations no significant alterations were observed. Because the discriminatory power of the current coagulase gene typing method is not great enough to be used as the sole method to type S. aureus, additional techniques are necessary. Sequence analysis of the repeated unit-encoding region for the typing of S. aureus may be potentially useful as an alternative to other current molecular typing techniques.

Base Sequence↗
PubMed1994

Nucleotide sequence analysis of enteropathogenic Escherichia coli (EPEC) adherence factor probe and development of PCR for rapid detection of EPEC harboring virulence plasmids.

The 1-kb BamHI-SalI fragment from plasmid pMAR2 termed the enteropathogenic Escherichia coli (EPEC) adherence factor (EAF) probe was cloned in pUC19 and pK18. The nucleotide sequence of this fragment was determined, and a set of primers was designed to amplify a 397-bp region associated with pMAR2 by PCR. An analysis of the whole EAF sequence with database libraries indicated no significant homology to any known genes. However, between bases 701 and 787 of the fragment, an 82.8% homology between the EAF and the insertion sequence IS630 of Shigella sonnei exists. The results of PCR with primers of the EAF sequence demonstrated that all of the 151 EAF probe-positive EPEC strains with localized adherence to HEp-2 cells yielded positive EAF PCR results. In contrast, none of the 277 EAF probe-negative strains reacted to the EAF PCR. In addition, the PCR assay was successfully used to generate vector-free digoxigenin-labeled EAF fragments that gave valid results in colony blot hybridization assays. The EAF PCR appears to be a specific and efficient method for the detection of EPEC strains carrying the EAF plasmids.

Adhesins, Escherichia coli↗
PubMed1994

Demonstration of Borrelia burgdorferi DNA in urine samples from healthy humans whose sera contain B. burgdorferi-specific antibodies.

Since the possibility of asymptomatic infection with Borrelia burgdorferi has been suggested by a positive serology found in healthy subjects, we hypothesized that these subjects might excrete borrelial DNA sequences in urine as happens in patients with Lyme borreliosis. We found borrelial sequences by nested PCR in the urine samples from 3 of 13 healthy B. burgdorferi antibody-positive adults but not in urine samples from 79 antibody-negative healthy controls. After therapy with doxycycline, the urine samples were repeatedly negative for B. burgdorferi DNA. We conclude that urinary excretion of borrelial DNA sequences may occur in seropositive healthy subjects during asymptomatic infection. Demonstration of such sequences in urine must be interpreted cautiously and may not necessarily prove a borrelial cause of disease.

Adult↗