PubMed Health⌕ Search

Biomedical subjects

R Mutters

Publications and source records attributed to R Mutters.

At least 19 recordsLinked to original sources
PubMed2005

[Recommendations for the treatment of respiratory complications in case of a viruspandemic].

In case of a viral pandemic without availability of effective vaccination, one can expect to be faced with additional 250 to 300 new admissions per hospital per week given the worst case scenario. Major complications are expected to occur in the respiratory system with the focus on viral pneumonia often complicated by bacterial superinfection. Frequently these patients will require artificial ventilation. The present infrastructure will not be capable of dealing sufficiently with such high numbers of casualties. These recommendations of the German Society for Pneumonology are based on the successful application of non-invasive ventilation for acute respiratory failure in recent years. It is of importance to achieve effective treatment by the use of relative simple means. The recommendation proposes to use a separate building in order to realize quarantine. In terms of diagnostic tools, a simple x-ray apparatus should be available. To monitor patients pulsoxymetry and ECG devices should be sufficient in most cases. For the treatment of acute respiratory insufficiency a sufficient number of ventilators, masks, tubing systems and filters should be kept in stock. In terms of medical treatment antibiotics to treat superinfections are of major importance. Analgesics, sedatives and intravenous fluids will also be needed. Oxygen should be available for every single patient. The recommendation gives detailed advise for the enforcement of hygiene control, diagnostic as well as therapeutic steps for in hospital treatment of high numbers of casualties of a viral pandemic.

Disease Outbreaks↗
PubMed2004

Influence of O(3)/O(2)-pneumoperitoneum as an oxidative stressor on duration of anaesthesia, loss of different reflexes and cytokine mRNA expression.

We analysed the effect of intraperitoneal insufflated ozonized oxygen on the anaesthetic strength generated by tribromoethanol, ketamine/xylazine, chloral hydrate, pentobarbital, and urethane in male Wistar rats. High dosages of anaesthetic drugs normally used for deep surgical anaesthesia were injected. The ozonized oxygen gas mixture was given five times daily on five consecutive days at 0.8 mg ozone/kg body weight before anaesthesia. The reflexes were measured 15, 30, 60, 90, 120, 180, and 240 min after injection of the anaesthetic drug. The sleeping time and the loss and regain of six different reflexes on noxious and non-aversive stimuli were recorded during the 4 h of observation. O(3)/O(2)-pneumoperitoneum (O(3)/O(2)-PP) reduced the sleeping time induced by tribromoethanol and ketamine/xylazine and increased it for chloral hydrate and pentobarbital. In accordance to the changes in the duration of anaesthesia, the O(3)/O(2)-PP induced significant changes in the loss of different reflexes. Additionally, the modulatory effect of the anaesthetic drugs on splenic cytokine mRNA expression was further influenced by O(3)/O(2)-PP. Thus, the influence of an oxidative stressor on anaesthetic potency and on the resting immune system has to be taken into account for experimental designs in which surgical anaesthesia is necessary for small laboratory animals.

Analysis of Variance↗
PubMed2004

Influence of different anaesthetics on pro-inflammatory cytokine expression in rat spleen.

We examined the effect of five anaesthetic drugs commonly used in laboratory animal research (tribromoethanol, ketamine/xylazine, chloral hydrate, pentobarbital, and urethane) on the expression of four pro-inflammatory cytokines. The anaesthetic agents were applied at dosages normally used for deep surgical anaesthesia. Semiquantitative image analysis of interleukin (IL)-1beta, IL-2, IL-6, and tumour necrosis factor alpha (TNFalpha) mRNA expression in the spleen of male Wistar rats 4 h after application of the anaesthetic drugs showed that these had moderate immunomodulatory effects. Ketamine/xylazine, chloral hydrate, and pentobarbital enhanced the basal expression of IL-1beta and IL-6 mRNA in rat spleen, while urethane reduced splenic IL-1beta mRNA expression. Tribromoethanol, ketamine/xylazine, and urethane reduced the basal TNFalpha mRNA levels, whereas TNFalpha mRNA expression was unaffected by chloral hydrate and by pentobarbital. The data demonstrate that these anaesthetics have slight, but significant, effects on the basal immune status of rats.

Adjuvants, Immunologic↗
PubMed2001

Phenotypic and genetic characterization of NAD-dependent Pasteurellaceae from the respiratory tract of pigs and their possible pathogenetic importance.

Nicotinamide adenine dinucleotide (NAD)-dependent Pasteurellaceae other than Actinobacillus pleuropneumoniae and Haemophilus parasuis are frequently isolated from the respiratory tract of pigs. The taxonomic classification and relevance for pathogenicity of these bacteria deserves further attention. In the present study, 107 of these NAD-dependent isolates from the porcine respiratory tract, primarily from lungs with pathological changes, were investigated. On the basis of phenotypic criteria, such as haemolysis, urease, catalase, and indole formation as well as other fermentative activities, 50 of the isolates were assigned to Actinobacillus minor, 36 isolates to Actinobacillus porcinus and 21 isolates to Actinobacillus indolicus. However, many isolates among the three species showed fermentative activities differing from those of the respective type strain of the species. Serotyping on the basis of heat-stable polysaccharide antigens and 16 rDNA sequencing also revealed substantial heterogeneity within each of the three species although they clustered together in three distinct groups in the phylogenetic analysis. These three groups of NAD-dependent bacteria are different from, or in a borderline position, to the existing species or genera within the family Pasteurellaceae. A considerable number of isolates of these three groups were isolated in pure cultures from pneumonic lungs. Consequently, it will be necessary to critically review the opinion, that these NAD-dependent Pasteurellaceae are only "agents colonizing the mucosa". Further, taxonomic examinations of the strains within these three groups are indispensable to testing isolates for their virulence in gnotobiotic pigs.

Animals↗
PubMed2001

Microbiological characteristics of subgingival microbiota in adult periodontitis, localized juvenile periodontitis and rapidly progressive periodontitis subjects.

OBJECTIVE: To describe the prevalence of the cultivable subgingival microbiota in periodontal diseases and to draw attention to the polymicrobial nature of periodontic infections. METHODS: The study population consisted of 95 patients, 51 females and 44 males, aged 14-62 years. Twenty-nine patients exhibited adult periodontitis (AP), six localized juvenile periodontitis (LJP), and 60 rapidly progressive periodontitis (RPP). Two to four pooled bacterial samples were obtained from each patient. Samples were collected with sterile paper points from the deepest periodontal pockets. The samples were cultured under anaerobic and microaerophilic conditions using selective and non-selective media. Isolates were characterized to species level by conventional biochemical tests and by a commercial rapid test system. RESULTS: Prevotella intermedia and Capnocytophaga spp. were the most frequently detected microorganisms in all diagnostic groups. Porphyromonas gingivalis and Peptostreptococcus micros were found more frequently in AP and RPP patients, while Actinobacillus actinomycetemcomitans and Eikenella corrodens were associated with AP, LJP and RPP patients. The other bacterial species, including Actinomyces spp., Streptococcus spp. and Eubacterium spp., were detected at different levels in the three disease groups. CONCLUSIONS: The data show the complexity of the subgingival microbiota associated with different periodontal disease groups, indicating that the detection frequency and levels of recovery of some periodontal pathogens are different in teeth affected by different forms of periodontal disease.

Adolescent↗
PubMed2001

Is characterization of a single isolate sufficient for valid publication of a new genus or species? Proposal to modify recommendation 30b of the Bacteriological Code (1990 Revision).

From 1990 to 2000, the number of published named taxa based upon new isolates at species and genus levels in International Journal of Systematic and Evolutionary Microbiology, formerly International Journal of Systematic Bacteriology, have increased by approximately four- and sevenfold, respectively. New taxa based upon characterization of only a single isolate remained at around 40% for both categories. The Bacteriological Code (1990 Revision) has no recommendations on the number of strains required for definition of new taxa. For a few groups, a minimum number of 5-10 strains has been suggested in minimal standards. Since an exponential increase in new taxa can be expected in the future, the authors discuss problems related to naming new species and genera based upon descriptions of a single isolate and suggest that this practice is re-evaluated. It is proposed that the following should be added to Recommendation 30b of the Bacteriological Code: 'Descriptions should be based on as many strains as possible (minimum five), representing different sources with respect to geography and ecology in order to be well characterized both phenotypically and genotypically, to establish the centre (from which the type strain could be chosen) and the extent of the cluster to be named. In addition, comparative studies should be performed, including reference strains that represent neighbouring species and/or genera, in order to give descriptions that are sufficiently detailed to allow differentiation from these neighbours.'

Bacteria↗
PubMed2001

Characterisation of a novel Mannheimia sp from Australian feedlot cattle.

OBJECTIVE: To characterise eight isolates of a Gram-negative organism obtained from the upper respiratory tract of cattle showing evidence of mild upper respiratory tract disease. DESIGN: The isolates were compared with the five recognised species within the genus Mannheimia - M haemolytica, M glucosida, M granulomatis, M ruminalis and M varigena--using a range of phenotypic and genotypic methods. RESULTS: Phenotypic characterisation indicated that the isolates belonged to the trehalose-negative [Pasteurella] haemolytica complex. This complex has recently been reorganised into five species within the new genus Mannheimia. Ribotyping performed using HindIII and a computerised analysis system indicated that the eight Australian isolates formed a distinct cluster that was related to, but different from, the five recognised species of Mannheimia. The 16S rRNA sequence of one isolate (BNO311) was determined and a phylogenetic analysis performed. Isolate BNO311 was distinct from the five named Mannheimia spp but did join a larger cluster consisting of rRNA cluster IV (M varigena) and the unnamed rRNA cluster V of Mannheimia. DNA:DNA hybridisation between isolate BNO311 and M haemolytica NCTC 9380T, M granulomatis P411 and Actinobacillus ligniersii NCTC 4189T all suggested similarities of approximately 30%. CONCLUSIONS: These phenotypic and genotypic characterisation studies suggest that the eight Australian isolates represent a new species of Mannheimia. Until further characterisation studies are performed, we are unwilling to propose a name for this taxon, preferring to refer to this possible new species as Bisgaard taxon 39 of cluster V of Mannheimia.

Animals↗
PubMed2000

DNA-DNA hybridization determined in micro-wells using covalent attachment of DNA.

The present study was aimed at reducing the time and labour used to perform DNA-DNA hybridizations for classification of bacteria at the species level. A micro-well-format DNA hybridization method was developed and validated. DNA extractions were performed by a small-scale method and DNA was sheared mechanically into fragments of between 400 and 700 bases. The hybridization conditions were calibrated according to DNA similarities obtained by the spectrophotometric method using strains within the family Pasteurellaceae. Optimal conditions were obtained with 300 ng DNA added per well and bound by covalent attachment to NucleoLink. Hybridization was performed with 500 ng DNA, 5% (w/w) of which was labelled with photo-activatable biotin (competitive hybridization) for 2.5 h at 65 degrees C in 2 x SSC followed by stringent washing with 2 x SSC at the same temperature. The criteria for acceptance of results were a maximum of 15% standard deviation, calculated as a percentage of the mean for four replicate micro-wells, and that DNA similarities were not significantly different in at least two independent experiments. The relationship between DNA similarities obtained by the micro-well method (y) and by the spectrophotometric method (x) was y = 0.534x+30.6, when these criteria had been applied to 23 pairs of strains of Actinobacillus species, avian [Pasteurella] haemolytica-like bacteria and Mannheimia species. The correlation (Pearson) between DNA similarities obtained by interchange of strains used for covalent binding and hybridization was 0.794. Significantly lower DNA similarities were observed by the spectrophotometric compared with the micro-well method for three pairs of hybridizations. After removal of these data, the relationship between DNA similarities obtained by the micro-well and spectrophotometric methods improved to y = 0.855x + 11.0. It was found that the accuracy and precision of the micro-well method was at the same level as that of the spectrophotometric method, but the labour and analysis time were reduced significantly. The use of hybridization in the micro-well format will allow DNA-DNA hybridizations to be carried out between all strains selected for a particular taxonomic study, in order to construct complete data matrices and improve species definition.

Animals↗
PubMed1999

Evaluation of ozonated oxygen in an experimental animal model of osteomyelitis as a further treatment option for skull-base osteomyelitis.

The standard treatment of chromic skull-base osteomyelitis is antibiotics and surgical removal of sequestrums. Hyperbaric oxygen therapy has been found to be a useful method for managing refractory cases of chronic osteomyelitis. Since a minimal blood supply is needed for hyperbaric oxygen therapy, chronic osteomyelitis can produce necrotic infected areas that are not nutrified and therefore not assessable for hyperbaric oxygen therapy. Ozone is known to be an oxidizing medium with a strong bactericidal effect. We investigated the influence of locally applied ozonated oxygen on the development of chronic osteomyelitis in an experimental animal model using the femur of the rabbit. The proximal sides of the femurs of 40 rabbits were prepared and a needle inserted into the intramedullary cavity. Osteomyelitis was induced with an infusion of Staphylococcus aureus and sodium morrhuate into the bone. The needle was left in a intramedular location. After a 4-week delay animals were randomly separated into treatment and control groups. The infected femur of treated animals was flushed three times a day with 20 ml of ozonated oxygen at an ozone concentration of 107 micrograms/ml O2 over periods of 2 or 4 weeks. Clinical, radiographic and microbiological findings were documented. Chronic osteomyelitis occurred in all animals. Ten rabbits were excluded from further study during the investigation because of excessive weight loss (> 15% of the original weight). Bacterial cultures showed no significant reduction of S. aureus concentrations in the ozone-treated group, although comparison of radiographic results revealed less serious osteomyelitis-related bone damage in these animals (P < 0.01). These findings indicate that refractory osteomyelitis in the head and neck may benefit from locally applied "flush" therapy with ozonated oxygen in addition to treatment with antibiotics, surgery and hyperbaric oxygen.

Animals↗
PubMed1999

Taxonomic relationships of the [Pasteurella] haemolytica complex as evaluated by DNA-DNA hybridizations and 16S rRNA sequencing with proposal of Mannheimia haemolytica gen. nov., comb. nov., Mannheimia granulomatis comb. nov., Mannheimia glucosida sp. nov., Mannheimia ruminalis sp. nov. and Mannheimia varigena sp. nov.

The present paper presents the conclusions of a polyphasic investigation of the taxonomy of the trehalose-negative [Pasteurella] haemolytica complex. Clusters previously identified by ribotyping and multilocus enzyme electrophoresis (MEE) have been evaluated by 16S rRNA sequencing and DNA-DNA hybridizations. Results obtained by the different techniques were highly related and indicated that the [P.] haemolytica complex contains distinct genetic and phenotypic groups. At least seven species were outlined, five of which were named. We refrained in formal naming of more groups until additional strains are characterized. Five 16S rRNA clusters were identified corresponding to distinct lineages previously outlined by MEE. Within 16S rRNA cluster I two distinct genotypic groups have been outlined in addition to [P.] haemolytica sensu stricto (biogroup 1). Each of the clusters II, III, IV and V represent at least one new species. The investigations underline that [P.] haemolytica sensu stricto only contains strains that do not ferment L-arabinose even though they are referred to as 'biotype A' of [P.] haemolytica. The five 16S rRNA clusters identified had a common root relative to the other species within the family Pasteurellaceae, and the overall sequence similarity among these five clusters was higher than what is observed within the existing genera of the family. The allocation of the trehalose-negative [P.] haemolytica complex to a new genus seems to be indicated. Based on the polyphasic investigation performed a new genus Mannheimia is proposed for the trehalose-negative [P.] haemolytica complex. At the present stage two previously named species are transferred to this new genus and three new species are described. [P.] haemolytica is reclassified as Mannheimia haemolytica comb. nov., whereas Pasteurella granulomatis, Bisgaard taxon 20 and [P.] haemolytica biovar 3J are reclassified and combined in the species Mannheimia granulomatis comb. nov. Mannheimia glucosida sp. nov. corresponds to [P.] haemolytica biogroups 3A-3H and the beta-glucosidase and meso-inositol-positive strains of [P.] haemolytica biogroup 9. All typable strains within M. glucosida belong to serotype 11. Mannheimia ruminalis sp. nov. consists of strains previously classified as Bisgaard taxon 18 and [P.] haemolytica biogroup 8D. Finally, Mannheimia varigena sp. nov. includes [P.] haemolytica biogroup 6 as well as Bisgaard taxon 15 and Bisgaard taxon 36. The type strains are NCTC 9380T (M. haemolytica), ATCC 49244T (M. granulomatis), CCUG 38457T = P925T (M. glucosida), CCUG 38470T = HPA92T (M. ruminalis) and CCUG 38462T = 177T (M. varigena).

Base Composition↗
PubMed1998

Catalase-positive Eikenella corrodens and Eikenella-like isolates of human and canine origin.

Ten catalase-positive isolates and one catalase-negative isolate that had been assigned to Eikenella corrodens were compared to the nomenclatural type strain regarding selected phenotypic and molecular features and chromosomal deoxyribonucleic acid (DNA) relatedness using the spectrophotometric method. Five catalase-positive human isolates were assigned to the genomic species Eikenella corrodens on the basis of high DNA relatedness levels. Three others, among them strain Chen UB 204, exhibited only moderate degrees of DNA relatedness to the type strain and with each other. Two catalase-positive isolates from dogs were closely interrelated, but yielded only low degrees of DNA binding with Eikenella corrodens and the Eikenella-like human isolates. These findings confirm that the human eikenellas comprise more than one genomic species and that the canine strains represent a distinct taxonomic entity. The differentiation of the strains investigated by conventional phenotypic features, hydrolytic enzyme reactions, and cellular carbohydrate patterns was considered.

Animals↗
PubMed1998

[Bacteremia in intra-arterial angiography, percutaneous transluminal angioplasty and percutaneous transhepatic cholangio-drainage].

PURPOSE: Prospective evaluation of the rate of bacteremia attributed to invasive radiological techniques. METHODS: Aerobic and anerobic blood cultures were obtained in 100 patients (62 men, 38 women; mean age 65 +/- 14 years) undergoing intra-arterial angiography (N = 50), PTA (N = 30) or percutaneous transhepatic biliary drainage (PTCD; N = 20). Samples were taken before the treatment (T0), immediately after puncture of the vessel or bile duct (T2), and 30 min after the termination of the procedure (T3). RESULTS: The overall rate of bacteremia was 18%. During diagnostic angiography a 16% rate of temporary bacteremia (no positive T3 samples) was observed. During PTA the rate was 27% (no clinically significant infectious disease) and during PTCD the rate was 10% (5% cholangitis with septicemia). We isolated staphylococci (S. epidermidis: N = 7, S. species: N = 3, S. aureus: N = 1), streptococci (N = 2), Propionibacterium acnes (N = 5), E. coli (N = 1), Enterococcus faecium (N = 1), Enterobacter species (N = 1), and Clostridium perfringens (N = 1). Apart from the one patient with cholangitis no clinical infectious complication occurred. CONCLUSION: Temporary bacteremia is rather frequent during invasive radiological procedures. Strictly aseptic conditions and antibiotic prophylaxis, specially in case of implantation of a permanent foreign body, is warranted.

Aged↗
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↗
PubMed1996

Serodiagnosis of Porphyromonas gingivalis infection by immunoblot analysis with recombinant collagenase.

The Porphyromonas gingivalis collagenase-specific serum immunoglobulin A (IgA), IgM, and IgG responses from 20 patients with early-onset periodontitis (EOP), 20 patients with adult periodontitis, (AP), and 20 age- and sex-matched healthy controls were examined by immunoblot analysis. A recombinant collagenase antigen used for the immunoblot analysis was produced by using the plasmid pGEX-2T, which allows the fusion between the collagenase and glutathione S-transferase. There was no significant difference in collagenase-specific IgG antibody detection between samples from the EOP, AP, and control groups. In contrast, 85% of AP and EOP sera had collagenase-specific IgA antibodies, whereas only 20% of control sera showed collagenase-specific IgA reactivity. Plaque samples from all groups were assessed by PCR with primers complementary to the collagenase-encoding gene prtC. The results indicated that 90% of AP and EOP plaque samples and 10% of control samples were positive for P. gingivalis. All patients with collagenase-specific IgA antibodies were PCR positive. The results of the study indicate a nearly complete concordance (k = 0.856) between the presence of collagenase-specific IgA antibodies and PCR detection of P. gingivalis. By using PCR as the "gold standard," the sensitivity and specificity of the IgA immunoblot test were 94.7 and 90.9%, respectively. Therefore, the recombinant collagenase is a potential candidate for use in the serodiagnosis of periodontitis.

Adult↗
PubMed1996

PCR reaction and dot-blot hybridization to monitor the distribution of oral pathogens within plaque samples of periodontally healthy individuals.

The purpose of this study was to determine the distribution of the putative periodontal pathogens Prevotella intermedia, Prevotella nigrescens, the three oral Capnocytophaga species (C. ochracea, C. sputigena, C. gingivalis), as well as Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans in plaque samples of periodontally healthy individuals. We chose a newly developed 16S rDNA directed polymerase chain reaction (PCR) and a previously described dot-blot hybridization assay to detect, differentiate, and quantify these bacteria directly in clinical samples. The subjects of these investigations were 66 sulcus fluid samples from 17 children (ages 3 to 5) attending a kindergarten, 48 sulcus fluid samples from 12 children (ages 9 and 10) from a primary school, and 25 subgingival plaque samples isolated from 6 different periodontally healthy dental students (ages 24 to 27). We were able to demonstrate the presence of P. nigrescens in 54 (kindergarten: 5; primary school: 33; students: 16) samples by PCR and quantified it by dot-blot hybridization. In addition, we found C. ochracea in 12 (kindergarten: 2; primary school: 10) samples by PCR reaction only. The other tested bacterial species were absent by the methods used. Furthermore we confirmed the specificity of our P. nigrescens-PCR in selected samples by enzyme electrophoresis.

Adult↗
PubMed1994

Rapid differentiation of avian Haemophilus-like strains by their whole-cell carbohydrate patterns.

The whole-cell carbohydrate patterns of 14 Haemophilus-like strains isolated from diseased birds were examined by capillary gas chromatography/mass spectrometry. The analysis of the peracetylated aldononitrile and O-methyloxime derivatives allowed the differentiation between the phenotypically and genetically different isolates. Starting from a pure culture the procedure needs only 5 hours for the preparation of the samples and 30 minutes for subsequent analysis and is of special value for rapid diagnosis.

Animals↗
PubMed1994

Differentiation of selected members of the family Neisseriaceae (Alysiella, Eikenella, Kingella, Simonsiella and CDC groups EF-4 and M-5) by carbohydrate fingerprints and selected phenotypic features.

On the basis of nucleic acid relationships, the family Neisseriaceae consists of the genera Neisseria, Kingella, Simonsiella and of Alysiella filiformis, Eikenella corrodens, and the CDC groups EF-4 and M-5. Differentiation, especially of the new members of the family, by conventional phenotypic characteristics is difficult and in some cases leads to doubtful results. On the other hand, cellular components proved to be suitable for the characterization of bacterial taxa. We investigated the cellular carbohydrates derived from whole cell hydrolysates of the above mentioned taxa with the exception of Neisseria by gas chromatography/mass-spectrometry. The analysis revealed characteristic patterns for all taxa considered, although with some species of which only few strains were investigated so far only preliminary results could be established. With the method used, the carbohydrate analysis could be completed within six hours starting from a pure culture. All strains investigated exhibited a common pattern with ribose, arabinose, glucose, and galactose. Qualitative and quantitative differences in contents of fucose, sorbose, rhamnose, threose, heptose, galactosamine and an amino sugar similar to glucosamine discriminated members of the taxa investigated. To achieve a taxonomically precise differentiation of the species investigated by conventional phenotypic features as available in commercial rapid test kits, these tests should be completed by the carbohydrate analysis technique presented.

Carbohydrates↗