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A Kaufhold

Publications and source records attributed to A Kaufhold.

At least 55 records · Page 3Linked to original sources
PubMed1992

M protein gene typing of Streptococcus pyogenes by nonradioactively labeled oligonucleotide probes.

A new approach for the typing of Streptococcus pyogenes is described. Oligonucleotide probes of 30 nucleotides in length were derived from currently known sequences of the N-terminal regions of M protein genes (emm genes). The oligonucleotides were labeled with digoxigenin-dUTP and hybridized to dot-blotted genomic DNA from 116 group A streptococcal strains of serotypes M-1, M-2, M-3, M-5, M-6, M-12, M-18, M-19, M-24, and M-49. Hybridization reactions were visualized with a chemiluminescent substrate. In comparison with conventional serological typing of expressed M proteins, the binding of the probes to the corresponding emm genes exhibited 100% sensitivity and specificity. The results emphasize the high degree of type-specific conservation of the N-terminal regions of emm genes from reference strains and epidemiologically unrelated U.S. and European clinical isolates. The existence of two distinct genetic subgroups among eight investigated M-49 strains was unequivocally shown by hybridization assays and further confirmed by nucleotide sequence data obtained from four selected M-49 strains. Because oligonucleotide probes are relatively easy to prepare, easy to handle, and known to give consistent interlaboratory results, the "oligotyping" technique appears to offer potential advantages over conventional serological typing methods.

Antigens, Bacterial↗
PubMed1992

[The vir-regulon of Streptococcus pyogenes: coordinate expression of important virulence factors].

Streptococcus pyogenes (group A streptococci; GAS) expresses important virulence factors like the antiphagocytic M protein, the complement factor-inactivating C5a peptidase and the immunoglobulin-Fc-binding proteins on its surface. The corresponding emm, scpA, and emm-related (fcrA, ennX) genes are adjacently encoded on the genome. They are coordinately in trans regulated by the positive regulatory VirR factor. The responsible virR gene is also located within this segment of the genome which was called vir-regulon. There are at least three different types of organization of the vir-regulon. A frequently encountered type is the "Large vir-regulon". It comprises from 5' to 3' the following genes: virR, fcrA, a relatively small emm, ennX, and a 4.6 kb version of scpA. Another common type is the "Small vir-regulon", which contains a virR deviating in its 3'-region, a relatively large emm, and a 3.5 kb version of scpA. The "Unusual vir-regulon" is less frequently detected. It closely resembles the small one, but harbors an additional 3 to 4 kb DNA fragment between emm and scpA, occasionally encoding an emm-related gene. The type of vir-regulon encoded by a GAS strain correlates to its serotype, its M class, and its expression of serum opacity factor. The structural genes of the vir-regulon are expressed at a high level during growth in exponential phase, under anaerobiosis, and at body temperature. The sensor molecule which modulates VirR activity according to these environmental conditions has not yet been detected.(ABSTRACT TRUNCATED AT 250 WORDS)

Adhesins, Bacterial↗
PubMed1992

[Infections by Streptococcus pyogenes: new aspects of diagnosis, epidemiology, clinical practice, and therapy].

Essential procedures for the cultural and serological laboratory diagnosis of Streptococcus pyogenes are described. A reliable and rapid species identification is achieved by serologic or biochemical tests. Direct antigen detection tests from throat swabs have broadened the diagnostic possibilities; however, they are often not satisfactory in terms of sensitivity. Typing of strains (either by classic serologic techniques or by molecular methods) is of high value for the study of clinical and therapeutic questions. In recent years, the epidemiology of the prevalent group A streptococcal strains has changed in Europe as well as in the U.S.: an increase of those M protein serotypes that are associated with higher virulence is being recognized. There is good evidence that the unexpected resurgence of rheumatic fever in the U.S. and the emerging number of life-threatening invasive and toxic manifestations of disease (including the toxic shock syndrome) in the U.S. and in Europe are related to the changing epidemiology. The existence of strains with rheumatogenic and nephritogenic potency has been established, but genetic host factors are a prerequisite for the sequelae as well. Although, based on experimental data, there are a lot of hypotheses concerning the nonsuppurative sequelae and the toxic shock syndrome, the exact pathogenesis of these diseases remains to be clarified. A thorough knowledge of the various clinical manifestations of group A streptococcal infections is necessary in order to apply the therapeutic and preventive measures in a rational and sophisticated manner. For most infections penicillins are considered the drug of choice, although no final conclusions regarding optimal dosages or the reasons for treatment failures can be made.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1992

[The possible nephrotoxicity of a bituminous coal dermatologic agent].

Nephrotoxic effects are discussed as a possible risk of dermatological coal tar preparations. Therefore, we have performed a renal tolerance study with a modern coal tar preparation for the scalp, Berniter. 15 healthy volunteers, randomly subjected to 3 different modes of application, applied the preparation: twice weekly (mode I) or daily (mode II) for a period of 8 weeks. In both modes, application time was 15 min. In mode III, the preparation was used under occlusion for 30 min every second day for a period of 4 weeks. Before, during and after treatment, renal functions and urinary phenol levels were assayed. No pathological change or impairment of renal functions was detected. A relationship between urinary phenol content and the coal tar treatment was not observed, either. We conclude that the coal tar preparation investigated here has no nephrotoxic properties.

Administration, Topical↗
PubMed1991

Isolation of Enterococcus mundtii from normally sterile body sites in two patients.

Enterococcus mundtii, a recently described nonmotile, yellow-pigmented enterococcal species, was isolated from a chronic thigh abscess and from operatively obtained sinus mucosa. It is emphasized that this species may be encountered in clinical specimens and that the correct species identification may be missed when commercially available identification systems are relied on.

Abscess↗
PubMed1991

[Evaluation of a rapid test for direct detection of group A streptococcal antigen in throat swabs. Study of 4 commercial test systems].

Four commercially prepared test reagent kits for the rapid screening of throat swabs for group A streptococci were examined in comparison to bacteriological cultures of 963 double throat swabs. The sensitivities of the test systems were 86.7% (Abbott Test Pack Strep A), 81.8% (Hybritech Tandem Icon Strep A), 79.6% (Pharmacia Phadirect Strep A), and 72.6% (Wellcome Reveal Colour Strep A) respectively. The specificity of the four tests was above 90%. Marked variations between different test reagent batches could be observed. The two tests based on the enzyme immunoassay principle proved to be superior to the agglutination tests investigated with respect to sensitivity and reading accuracy. Our results are evaluated in the light of the published literature on these tests.

Antigens, Bacterial↗
PubMed1990

Flavimonas oryzihabitans septicaemia in a T-cell leukaemic child: a case report and review of the literature.

We describe the first case of septicaemia with Flavimonas oryzihabitans reported from Germany and possibly associated with colonisation of a venous port system. The patient, an 8-year-old T-cell leukaemic girl, was receiving a third course of chemotherapy before bone marrow transplantation. The cardinal symptom, fever, subsided when the venous port system for administration of drugs was no more used. The organism was tested extensively for characteristic biochemical features and antimicrobial susceptibility. We discuss the relevant literature and suggest the means of making a definitive microbiological diagnosis.

Anti-Bacterial Agents↗
PubMed1989

Few-minutes tests for the identification of group A streptococci and enterococci with chromogenic substrates.

The usefulness of paper strip tests for rapid identification of Streptococcus pyogenes and enterococci cultured on blood agar plates was investigated. The paper strips used contain dried chromogenic substrates for pyrrolidonyl peptidase (PYRase) and beta-glucosidase (beta-Gluc). Material from only a few colonies needed to be applied to the test strips. The reactions could be read after two min (PYRase) and 5-7 min (beta-Gluc), respectively. Results from testing 503 streptococcal strains were evaluated. The reactions proved very useful for rapid differentiation of S. pyogenes and enterococci from human sources. Nearly all strains of these streptococcal species showed positive reactions in the PYRase test whereas only the enterococci (E. faecalis and E. faecium) were positive for both enzymes.

Chromogenic Compounds↗
PubMed1988

[Systemic infection caused by Streptococcus suis].

Streptococcus suis type 2 was isolated from blood and cerebrospinal fluid in a 49-year-old butcher as the causative organism of a generalized septic infection with meningeal involvement. High-dosage penicillin G treatment quickly terminated the fever and all neurological signs disappeared completely. Streptococcus suis type 2 causes a zoonosis, which usually occurs as an occupational disease among those handling pigs or pork (farmers, butchers etc.). Sequelae of such infection not rarely are damage to the VIIIth cranial nerve, especially loss of hearing.

Animals↗
PubMed1985

[Serotypes and antibiotic sensitivity of Streptococcus pneumoniae (pneumococci) in the cologne area (1980-1982)].

The commercial availability of a 14-valent pneumococcal polysaccharide vaccine justifies repeated investigations of the prevalent pneumococcal serotypes to estimate the probable efficacy of vaccination for patients at high risk of pneumococcal infection. Immunoprophylaxis of infection with S. pneumoniae appears to gain importance since more and more isolates with reduced sensitivity to antibiotics including penicillin are reported. Our investigation of 324 pneumococcal strains, isolated between October 1980 and December 1982 from various clinical sources at the Institute of Hygiene, Cologne, showed that the distribution of predominant serotypes did not differ substantially from that of 1970 to 1972. This distribution resembled closely to those reported from other European countries. However, a lower percentage of the Cologne isolates belonged to the serotypes of the 14-valent vaccine. The potential coverage of the vaccine in our area would probably be in the range of about 60% or less. Determination of the antibiotic sensitivity of the isolates demonstrated resistances against tetracycline, chloramphenicol, and macrolides. Moreover, 1.7% of the strains were "relatively resistant" to penicillin G (MIC 0.125 to 0.25 mg/l). Some isolates were multiply resistant.

Anti-Bacterial Agents↗
PubMedDate not supplied

Endocarditis caused by Gemella haemolysans.

Gemella haemolysans, a coccus related to the "Streptococcaceae", was isolated from the blood of a patient with endocarditis. The patient was successfully treated with a combination of penicillin G and tobramycin, followed by clindamycin. The taxonomy of this organism, especially its relationship to "Streptococcus morbillorum" is discussed and previously reported cases of Gemella infections are reviewed.

Anti-Bacterial Agents↗
PubMedDate not supplied

Ochrobactrum anthropi bacteremia: report of four cases and short review.

Ochrobactrum anthropi, formerly "Achromobacter" CDC group Vd, is a nonfermentative, nonfastidious gram-negative bacillus, that only recently has been given attention as a potential human pathogen. Over a 2-year period, we observed four patients with multiple blood cultures that were positive for the organism. The patients had acute leukemia as underlying disease, and presented with clinical and microbiologic features consistent with catheter-related bacteremia. In three of the patients the infection initially appeared to be unrelated to chemotherapy-associated profound neutropenia and occurred early after, or was the reason for, hospital admission. The antimicrobial susceptibility of the isolates varied: unlike previously reported cases, resistance in some of our isolates included aminoglycosides, newer fluoroquinolones, and trimethoprim-sulfamethoxazole. Despite in vitro susceptibility to imipenem in initial isolates, treatment of two patients with this agent obviously failed to eradicate the organism, and the patients either relapsed with bacteremia shortly after discontinuation of treatment or remained persistently febrile and bacteremic. O. anthropi appears to be increasingly recognized as a human opportunist pathogen associated with intravascular catheters and unpredictable multiple antibiotic resistance.

Adult↗
PubMedDate not supplied

Bacteremia caused by Stomatococcus mucilaginosus: report of seven cases and review of the literature.

During a three-year period eight patients with blood cultures positive for Stomatococcus mucilaginosus were identified at two university hospitals. One patient without any signs of infection had a central venous catheter that was colonized with this organism, two patients had transient bacteremia without definite relationship to underlying disease, whereas the remaining five patients suffered from clinically significant infections. Of these last five patients, one had undergone prior head and neck surgery and four had hematologic malignancy with mild to severe neutropenia; two of the latter patients developed the infection subsequent to dental surgery. Besides neutropenia and mucosal damage in the oropharynx, quinolone antibacterial prophylaxis may have been an additional risk factor for the development of S. mucilaginosus bacteremia in these patients. A thorough review of the literature revealed that in addition to our findings, endocarditis and foreign body infections are further typical clinical manifestations. Although the overall antibiotic susceptibility pattern of S. mucilaginosus resembles that of streptococci, it is suggested that penicillin G may not be the drug of choice for initial therapy of particularly severe infections. S. mucilaginosus can be easily differentiated from other gram-positive bacteria when certain key criteria (e.g. adherence to agar surfaces, poor growth on Mueller-Hinton agar, presence of a capsule) as well as an array of biochemical tests, including commercially available identification systems, are applied. Our own and published data emphasize that both microbiologists and clinicians should be increasingly aware of this opportunistic pathogen.

Adolescent↗
PubMedDate not supplied

Does aggregation substance of Enterococcus faecalis contribute to development of endocarditis?

Aggregation substance (AS) of Enterococcus faecalis which is encoded by so-called sex pheromone plasmids enables the bacteria to bind to in vitro-cultured pig kidney tubular cells. It is reported that the presence of AS is not of pivotal importance for the ability of E. faecalis to cause infective endocarditis (EN). The lines of evidence for this are twofold: 1) sex pheromone plasmids and, therefore, the gene for AS were not present more often in epidemiologically unrelated strains of E. faecalis isolated from human cases of EN than in isolates from well-water (26 vs. 18%); 2) the presence of the adhesin did not correlate with the establishment of EN in an animal (rat) model. The data are discussed with respect to the specificity of interaction of AS with eukaryotic cells and the results of other studies.

Adhesins, Bacterial↗