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K Pelz

Publications and source records attributed to K Pelz.

At least 19 recordsLinked to original sources
PubMed2006

Differences in the fatty acid composition of KB-cells and gingival keratinocytes is culture medium additive dependent.

The influence of culture medium additives foetal bovine serum (FBS), serum effective substitutes (SES) and human autologous serum on the fatty acid profile of KB-cells and human gingival keratinocytes was examined. The KB-cells were cultivated in RPMI medium added with FBS or SES and the gingival keratinocytes in D-MEM added with FBS or human autologous serum. Two days before the cells were prepared for gas chromatography (GC), the media were changed to serum- and antibiotic-free media. Whole fatty acids of the cells were analysed using GC and the fatty acid profiles were compared. KB-cells as well as gingival keratinocytes changed their fatty acid composition, according to the medium additive used. Significant differences were observed. In the case of KB-cells cultivated with SES the fatty acid changes suggest an increase of the membrane fluidity. Corresponding and significant differences were observed with gingival keratinocytes cultivated in medium added with human autologous serum: the membrane fluidity of the gingival keratinocytes was increased. It is supposed that an increased membrane fluidity caused by a different fatty acid spectrum of the host cell may relate to mechanisms of bacterial adhesion. Consequently, in vitro studies on invasion and adhesion of bacteria or virus are dependent on the medium used. Further analyses are necessary of the functional effects caused by differences in the content of specific FAs, especially with regard to the application of cultivated cells in the field of tissue engineering.

Cell Line, Tumor↗
PubMed2005

Bacterial colonization on different suture materials--a potential risk for intraoral dentoalveolar surgery.

In this in vivo and in vitro study on resorbable (Monocryl and nonresorbable (Deknalon) monofilament sutures used in intraoral dentoalveolar surgery the bacterial colonization was compared. For the in vivo study the sutures were applied in 11 patients during dental surgery. Eight days postoperative the sutures were removed and the adhered bacteria were isolated and identified by biochemistry, morphology, antibiotic susceptibility, and gas chromatography. The colonization was studied by scanning electron microscopy. Aerobic and anaerobic bacteria were isolated in nearly equal colony-forming units (cfu) on each suture. In comparison with Monocryl about 15% more aerobic and anaerobic strains were isolated on Deknalon. Regarding the pathogens only, about three times more anaerobic strains were isolated on both sutures in total. Additionally, more pathogens were found on Deknalon than on Monocryl (aerobic >40%, anaerobic >25%). The variety of bacteria correspond with purulent infections, not with normal oral flora. Intraindividual comparisons of cfu showed differences in dependence of the patient as described for subgingivale plaques. For the in vitro study the sutures were incubated with Streptococcus intermedius and Prevotella intermedia for 0.5 h. Scanning electron microscopy was performed to examine qualitatively the level of bacterial adherence. After 0.5 h the bacteria adhered very well. The colonization rate of Streptococcus intermedius on both sutures was similar. Coccoid bacteria within biofilms were seen. The growth of Prevotella intermedia was much better on Deknalon than on Monocryl. The risk of bacteremia at the time of suture removal is discussed.

Bacteria↗
PubMed2004

Effect of different crown contours on periodontal health in dogs. Microbiological results.

OBJECTIVES: In some clinical circumstances, i.e. in cases when the upper anterior region has to be restored by prosthetic means, it is necessary to place the margins of crowns and fixed partial dentures subgingivally. In addition, in periodontally compromised patients the restoration sometimes has to be overcontoured in order to replace the lost interdental papilla. The overcontoured crown margin may influence the subgingival bacterial composition. Therefore, the aim of the present investigation was to evaluate the effect of three different subgingival crown contours in dogs on the composition of the subgingival microbiota. METHODS: In four adult beagle dogs the second and third premolars were prepared in three quadrants and restored with single gold crowns. The unprepared second and third premolars in the last quadrant served as controls. The crowns had three different emergence profiles including a normal contour, a 30 degrees and a 50 degrees over-contour. During the entire study period, professional oral hygiene was performed seven times a week. Microbiological samples were harvested from four sites of test and control teeth (mesial, distal, buccal and lingual) at baseline, after 3 months, and after 5 months. RESULTS: The microbiological analysis (DNA-DNA hybridization technique) of the subgingival microbial flora revealed a dominance of P. intermedia, T. denticola and C. showae in all test and control groups at baseline. At three months, the total amount of bacteria increased and a broader variety of bacterial species could be detected. The detection frequency of most bacterial species increased from baseline to the 5-month evaluation. The frequency of detection of some species was higher in the 30 degrees and 50 degrees overcontoured test groups compared to the normal contour group and to the natural teeth. CONCLUSIONS: It can be concluded within the limits of this investigation that overcontoured gold crowns placed subgingivally have only slight effects on the microbiological composition in dogs when an intensive oral hygiene regimen was executed.

Animals↗
PubMed2002

Nosocomial pneumonia: a cost-of-illness analysis.

BACKGROUND: We investigated incremental cost of nosocomial pneumonia (NP) from the perspective of a hospital and health insurance funds. PATIENTS AND METHODS: The incremental cost was determined by calculating total costs for pneumonia patients and controls using prospective and retrospective matched-pairs analysis with 29 and 37 matched pairs, respectively. RESULTS: Compared to controls, patients who developed pneumonia had to be on artificial ventilation 5 days longer, needed markedly more intensive care with 6.55 additional days in intensive care. Excess cost per pneumonia patient amounted to DM 14,606 (95% CI: DM 5,285-23,927) from the hospital's perspective and to DM 7,988 (95% CI: DM 5,281-10,894) according to statutory insurance charges. According to the retrospective anaLysis carried out on the neurosurgical and neurological intensive care wards, pneumonia patients were ventiLated 5 days longer than patients without pneumonia, needed more intensive care over 30 days and had an additional 14.03 days of intensive care and 10.14 more days in hospital. Excess cost per patient was DM 29,610 (95% CI: DM 23,054-36,174) from the hospitals perspective and DM 18,000 (95% CI: 14,885-21,020) according to the statutory insurance criteria. CONCLUSION: The study gives insight into the structure of incremental cost caused by NP and shows that based on a conservative cost calculation the incremental cost per NP patient is higher for the hospital than for health insurance funds which indicates a significant financial deficit for the hospital. Antibiotics and microbiology together only contribute 6.8% to incremental cost. Therefore in a cost saving initiative their close relationship to length of hospitalization must be considered.

Anti-Bacterial Agents↗
PubMed2001

Surveillance of nosocomial infections in a neurology intensive care unit.

To identify overall and site-specific nosocomial infection (NI) rates in patients receiving neurological intensive care therapy, a prospective study was started in 1997 in the ten-bed neurological intensive-care unit (NICU) of the University Hospital of Freiburg, Germany. Case records and microbiology reports were reviewed twice a week, and ward staff were consulted. NI were defined according to the Center for Disease Control and Prevention (CDC) criteria and were categorised by specific infection site. Within 30 months, 505 patients with a total of 4,873 patient days were studied (mean length of stay: 9.6 days). 122 NI were identified in 96 patients (74 patients with one, 18 with two and 4 with three infections. An incidence of 24.2/100 patients and incidence density of 25.0/1,000 patient days of NI in the neurological ICU were documented. Site-specific incidence rates and incidence densities were: 1.4 bloodstream infections per 100 patients (1.9 central line-associated BSIs per 1,000 central line-days), 11.7 pneumonias per 100 patients (20.4 ventilator-associated pneumonias per 1,000 ventilator-days), 8.7 urinary tract infections per 100 patients (10.0 urinary catheter-associated urinary track infections (UTIs) per 1,000 urinary catheter-days). Additionally, 0.4 cases of meningitis, 0.8 ventriculitis, and 1.2 other infections (catheter-related local infection, diarrhea) were documented per 1,000 patient days. 15% of nosocomial pathogens were A. baumannii (due to a outbreak of an nosocomial pneumonia with A. baumannii), 13% S. aureus, 10% E. coli, 7% CNS,7% Bacteroides spp., 7% Enterobacter spp., 6,5% Klebsiella spp.,5.9% enterococci, 5.9% streptococci, and 4.7% Pseudomonas spp. In eight cases of NI no pathogen could be isolated. In future, data on NI in NICUs should be assessed in greater detail, both to improve the quality of care and serve as a basis for identification and implementation of the most effective measures by which to prevent these infections in patients receiving intensive neurological care.

Adolescent↗
PubMed2001

Antibacterial properties of electron beam-sterilized Gutta-Percha cones.

The purpose of the study was to determine the effect of electron beam sterilization on gutta-percha cones (GPCs) at different times after sterilization. An agar diffusion test was used with -one aerobic bacterium (Bacillus subtilis) and five oral anaerobic bacteria (Fusobacterium nucleatum, Peptostreptococcus micros, Porphyromonas gingivalis, Propionibacterium acnes, and Veillonella parvula). With each microorganism 30 agar plates were prepared, evenly distributed among three groups (group 1: unsterilized GPCs; groups 2 and 3: GPCs sterilized by electron beam irradiation 5 months and 5 yr before, respectively). One GPC of the selected group was placed in each plate. After incubation the area of inhibition was read on the agar plates. Inhibition of growth was significantly different for the tested microorganisms. However no significant difference was observed between the sterilized and unsterilized GPCs. Both the tested sterilized and unsterilized GPCs impair the growth of endodontic pathogens, with no influence of the time elapsed since sterilization.

Agar↗
PubMed2001

Bartonella schoenbuchii sp. nov., isolated from the blood of wild roe deer.

The genus Bartonella comprises two human-specific pathogens and a growing number of zoonotic or animal-specific species. Domesticated as well as wild mammals can serve as reservoir hosts for the zoonotic agents and transmission to humans may occur by blood sucking arthropods or by direct blood to blood contact. Humans may come into intimate contact with free-ranging mammals during hunting, especially during evisceration with bare hands, when accidental blood to blood contact frequently occurs. The objective of this work was to determine the presence and the polymorphism of Bartonella strains in wild roe deer (Capreolus capreolus) as the most widely spread game in Western Europe. We report the isolation of four Bartonella strains from the blood of five roe deer. These strains carry polar flagella similar to Bartonella bacilliformis and Bartonella clarridgeiae. Based on their phenotypic and genotypic characteristics, three of the four roe deer isolates were different and they were all distinct from previously described Bartonella species. They can be distinguished from each other and from other Bartonella species by their protein profile, ERIC-PCR pattern, 16S rRNA and citrate synthase (gitA) gene sequences, as well as by whole DNA-DNA hybridization. In spite of their considerable heterogeneity, all four strains fulfil the criteria for belonging to a single new species. The name Bartonella schoenbuchii is proposed for this new species. The type strain R1T of Bartonella schoenbuchii has been deposited in the National Collection of Type Cultures as NCTC 13165T and the Deutsche Sammlung von Mikroorganismen und Zellkulturen as DSM 13525T.

Animals↗
PubMed2001

Small intestinal bacterial overgrowth in patients with cirrhosis: prevalence and relation with spontaneous bacterial peritonitis.

OBJECTIVES: The significance of small intestinal bacterial overgrowth in patients with cirrhosis is not fully understood and its diagnostic criteria are not uniform. We examined the association of small intestinal bacterial overgrowth with spontaneous bacterial peritonitis and compared various microbiological criteria. METHODS: Jejunal secretions from 70 patients with cirrhosis were cultivated quantitatively and classified according to various definitions. Clinical characteristics of patients were evaluated and the incidence of spontaneous bacterial peritonitis was monitored during a 1-yr follow-up. RESULTS: Small intestinal bacterial overgrowth, defined as > or = 10(5) total colony-forming units/ml jejunal secretions, was present in 61% of patients. Small intestinal bacterial overgrowth was associated with acid-suppressive therapy (p = 0.01) and hypochlorhydria (p < 0.001). Twenty-nine patients with persistent ascites were observed. Six episodes of spontaneous bacterial peritonitis occurred after an average 12.8 wk. Occurence of spontaneous bacterial peritonitis correlated with ascitic fluid protein concentration (p = 0.01) and serum bilirubin (p = 0.04) but not with small intestinal bacterial overgrowth (p = 0.39). Its association with acid-suppressive therapy was of borderline significance (hazard ratio = 7.0, p = 0.08). CONCLUSIONS: Small intestinal bacterial overgrowth in cirrhotic patients is associated with acid-suppressive therapy and hypochlorhydria, but not with spontaneous bacterial peritonitis. The potential role of acid-suppressive therapy in the pathogenesis of spontaneous bacterial peritonitis merits further studies.

Adult↗
PubMed2000

[Endophthalmitis: improvement of culture results].

BACKGROUND: Infectious endophthalmitis is a rare, but serious complication. Identification of the responsible microorganism is important for prognosis and therapy. In the literature positive cultures have been reported in 35-85% of cases. The purpose of our work was to improve the proportion of positive culture results. METHODS AND PATIENTS: All necessary materials (culture media: Columbia, Hämatin, ENDO and yeast-cystein-blood agar, fungus media) and instructions were always available in the operation theater. Thus, intraocularly derived samples could be cultured by less experienced residents right in the operation theater, especially off duty. At night the culture plates were incubated in the Department of Ophthalmology under optimal conditions and passed on to an experienced microbiologist later. Culture results of the first 21 patients suffering from endophthalmitis (acute or chronic postoperative, endogen) after introduction of this "endophthalmitis set" were compared to the results of the 21 patients before. RESULTS: As a result of the introduction of the "endophthalmitis set", the proportion of positive culture results improved from 11/21 to 18/21. The detected microorganisms were all representative of the pathogens commonly causing endophthalmitis (gram-positive bacteria, anaerobic bacteria). CONCLUSION: An appropriate culture set that is always available in the operation theater may increase the number of positive cultures dramatically and hence help to find the adequate antibiotic treatment in endophthalmitis cases.

Bacteria↗
PubMed2000

Inflammatory consequences of the translocation of bacteria and endotoxin to mesenteric lymph nodes.

BACKGROUND: Translocation of intestinal bacteria to mesenteric lymph nodes (MLNs) has been documented in humans under a variety of circumstances, yet its clinical significance remains to be established. The aim of this study was to correlate detectable translocation to MLNs of bacteria and endotoxin with local and systemic signs of inflammation. METHODS: From each of 10 patients with carcinoma of the cecal region two MLNs were harvested prior to resection. The presence of bacteria and endotoxin in the lymphatic tissue and blood was determined by culture methods and DNA preparation (PCR) and by a Limulus assay, respectively. Inflammatory mediators were determined in plasma and in MLN homogenates. RESULTS: Viable bacteria were detected in MLNs of 7 patients and in 9 of 20 lymph nodes. PCR revealed traces of bacteria in 4 patients and in 6 of their MLNs. Combining both modalities, the translocation rate was 80% and 55% for patients and MLNs, respectively. There was no detectable bacteremia. Endotoxin was found in the plasma of 7 patients and in 9 MLNs from 5 patients. There was no correlation between culture findings and endotoxin concentrations. Moreover, bacteriological data did not correspond to local or systemic inflammation. The group of MLN with detectable endotoxin differed significantly from LPS-negative nodes with respect to interleukin-6, interleukin-10, and sCD14. Systemic concentrations of endotoxin and inflammatory parameters did not correspond to levels within MLNs. CONCLUSION: Translocation to MLNs occurs in patients with cecal carcinoma. This, however, seems not to be of major clinical significance if no additional physiologic insults are encountered. Irrespective of the presence of bacteria, there are variations in inflammatory reactions between lymph nodes from one and the same patient, probably reflecting fluctuating response mechanisms to low-grade translocation.

Analysis of Variance↗
PubMed1999

Routine identification of Campylobacter jejuni and Campylobacter coli from human stool samples.

Correct identification of Campylobacter jejuni and Campylobacter coli isolates to the species or subspecies level is a cumbersome but nevertheless important task for a routine diagnostic laboratory. The widely used biochemical tests might be often misleading while more sophisticated phenotypic or genotypic methods are not generally available. This investigation was performed to assess the performance of common biochemical identification in comparison with species-specific PCR and gas liquid chromatography of whole cell fatty acid extracts (GLC). A total of 150 consecutive isolates from human stool samples were investigated (134 C. jejuni ssp. jejuni, 14 C. coli, two Helicobacter pullorum). From these 144, 145 and 149 isolates were correctly identified by biochemistry, GLC and PCR, respectively. Biochemical identification of all C. jejuni isolates was confirmed by PCR. GLC detected both H. pullorum strains but misidentified two C. coli strains as C. jejuni and one C. jejuni strain as C. coli. No single method can be defined as 'gold standard' for identification of C. jejuni and C. coli but a combination of techniques is needed. Therefore a stepwise identification scheme starting with biochemical reactions is suggested. All results other than C. jejuni should be confirmed by further methods. For indoxyl acetate-positive isolates species-specific PCR is recommended while GLC seems to be advantageous in indoxyl acetate-negative isolates.

Campylobacter coli↗
PubMed1999

Nosocomial infections in a neurosurgery intensive care unit.

In order to identify overall and site-specific nosocomial infection (NI) rates in patients receiving neurosurgical intensive care therapy, a prospective study was started in February 1997 in the eight-bed neurosurgical ICU of the University Hospital of Freiburg, Germany. Case records were reviewed twice a week, all microbiology reports were reviewed and ward staff was consulted. NI were defined according to the CDC-criteria and were categorised into specific infection sites. Within 20 months, 545 patients with a total of 5,117 patient days were investigated (mean length of stay: 9.4 days). 113 NI were identified in 90 patients (72 pts. with one, 13 with two and 5 with three infections, respectively). A moderate to high overall incidence (20.7/100 pts.) and a moderate incidence density (22.1/1,000 patient days) of NI in the neurosurgical ICU could be documented; these figures are well within the range of published data. Site specific incidence rates and incidence densities were: 1 bloodstream infection per 100 patients (0.9 central line-associated BSIs per 1,000 central line-days), 9 pneumonias per 100 patients (15.1 ventilator-associated pneumonias per 1,000 ventilator-days), 7.3 urinary tract infections per 100 patients (8.5 urinary catheter-associated UTIs per 1,000 urinary catheter-days). Additionally, 1.1 cases of meningitis, 0.7 brain abscesses/ventriculitis, and 1.7 other infections (surgical site infection, bronchitis, catheter related local infection, diarrhoea) were documented per 100 patients, respectively. 14.6% of isolated pathogens were E. coli, 10.2% enterococci, 9.6% S. aureus, 6.4% CNS, 6.4% Klebsiella spp., 5% Enterobacter spp. and 5% Pseudomonas spp. In 11 cases of NI no pathogen could be isolated.

Adolescent↗
PubMed1998

Discrimination of Helicobacter pullorum and Campylobacter lari by analysis of whole cell fatty acid extracts.

Helicobacter pullorum and Campylobacter lari are rarely isolated from humans with acute enteritis. Hitherto the two species could only be identified by genotypic techniques. Gas liquid chromatography of whole cell fatty acid extracts is described as the first phenotypic method for discrimination of the two species. Cholesteryl glucoside, a characteristic feature of the genus Helicobacter, but seldom found in other bacteria, could not be detected in Helicobacter pullorum. Therefore, rapid determination of this glycolipid may serve as a discrimination marker for Helicobacter pullorum from most other Helicobacter species.

Animals↗
PubMed1997

[Chlamydia pneumoniae infection in a family].

UNLABELLED: HISTORY AND SYMPTOMS: For 11 weeks a 38-year-old woman had suffered from a respiratory infection with peribronchitis, nocturnal coughing fits and earache. INVESTIGATIONS, TREATMENT AND COURSE: The Chlamydia-CFR titre was raised. Subsequent throat swabs of her husband and two daughters grew Chlamydia pneumoniae (C.p.), but not in her case; 5 days earlier she had been started on roxithromycin. 3 weeks before the patient fell ill her two daughters had a flu-like illness with cough and subfebrile temperature and her husband also had flu-like symptoms, which regressed after few days. Antibiotic treatment with roxithromycin improved the symptoms in the mother and older daughter, but the younger daughter was not given treatment because she had no symptoms at the time the microorganism had been isolated. She developed joint symptoms, like those of reactive arthritis, 12 weeks after the mother's illness had begun, and conjunctivitis 5 weeks later. CONCLUSIONS: It is likely that the daughters had the C.p. infection first and then infected their parents. While the father's and older daughter's illness quickly regressed, the mother became quite ill. Her serology was positive for a primary infection in adulthood, but in the daughters the serology was negative and, despite demonstration of the organism, the diagnosis of acute C.p. infection could not be made.

Adolescent↗
PubMed1997

DNA-probes for the differentiation of Capnocytophaga species.

We designed oligonucleotides to differentiate between the seven currently known Capnocytophaga species. The oligonucleotides were labelled non-radioactively at the 3' end with digoxigenin. The specificity could be demonstrated in a dot-blot hybridization assay by using the type strains, reference strains, and 37 clinical Capnocytophaga isolates as well as 11 representative strains of other taxa as a template. The sensitivity of the assay was calculated with 10(3) bacteria per dot.

Bacterial Typing Techniques↗