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Biomedical subjects

S Hoffmann

Publications and source records attributed to S Hoffmann.

At least 181 records · Page 10Linked to original sources
PubMed1985

The throat carrier rate of group A and other beta hemolytic streptococci among patients in general practice.

In a one-year multicenter study in general practice the rate of asymptomatic throat carriage of group A beta hemolytic streptococci (GABHS) was investigated. 2,626 patients, none of whom had had sore throat or any other streptococcal illness during the preceding three months, were evaluated. The GABHS carrier rate was 2.2% with no sex or season dependent variation, and it was 10.9% in patients less than or equal to 14 years of age, 2.3% in patients between 15 and 44 years old, and 0.6% in patients greater than or equal to 45 years old. An additional 7.2% of the patients carried beta hemolytic streptococci of groups B, C, or G. For groups C and G the influence of age on carrier rates was similar to that found for GABHS. Tetracycline resistance was found in 21% of the group A strains, in 61% of the group B strains, and in 28% of the group C and group G strains.

Adolescent↗
PubMed1985

Lack of reliability of primary grouping of beta-hemolytic streptococci by culture of throat swabs with streptocult supplemented with bacitracin disks in general practice.

Fifty-eight general practitioners took throat swabs from 434 patients with sore throats. Office cultures were performed on Streptocult supplemented with bacitracin disks in an attempt to carry out primary grouping of beta-hemolytic streptococci (BHS). In 424 cases the findings were compared with those obtained in a microbiological laboratory. Streptocult showed a sensitivity of 75% and a specificity of 84% in the detection of BHS. The office-performed grouping procedure of the correctly detected BHS, however, only had a sensitivity of 65% and a specificity of 87%. Overall, as many as 45% of the patients with BHS group A were misdiagnosed. The unsatisfactory results obtained with primary grouping of BHS may be due partly to incorrect determinations of the diameter of the inhibition zone around the bacitracin disks and partly to an inappropriate choice of breakpoint. It is concluded that cultures of throat swabs on Streptocult in general practice should not be accompanied by attempts to carry out primary grouping with bacitracin disks. A laboratory investigation showed that incubation at room temperature for 48 h and at 35 degrees C for 24 h gave identical BHS positivity rates.

Bacitracin↗
PubMed1984

Blood ammonia measurement using a simple reflectometer.

We have assessed a compact Blood Ammonia Checker System (Ammonia Checker) consisting of a reflectometer which measures the intensity of colour formed by blood ammonia on a bromocresol green indicator reagent plate. The results show good correlation (r = 0.95) with our routine chemical method and a regression line y = 0.835X - 1.468. The Ammonia Checker has good precision (CV less than 10%) at the critical blood ammonia concentration and accurately measures predetermined ammonia concentrations. Blood sampling is improved with a precision pipette. The Ammonia Checker is simple, convenient and reliable and is ideally suited for a laboratory required to perform an urgent blood ammonia measurement.

Ammonia↗
PubMed1984

Silver sulfadiazine: an antibacterial agent for topical use in burns. A review of the literature.

Topical antibacterial treatment is of major importance in the burn patient. Silver sulfadiazine is an effective agent with low toxicity and few side effects. Deposition of silver in tissues, and absorption of sulfadiazine are both minimal. Present and future problems are represented by the emergence of resistant Gram negative bacilli, including Pseudomonas aeruginosa. The development of related metal sulfadiazines to be used against resistant bacteria is on an investigational stage, and clinical trials are few. Silver sulfadiazine may be used in a variety of other conditions than burns.

Administration, Topical↗
PubMed1983

Fatal meningitis with group JK Corynebacterium in a leukopenic patient.

A case of fatal meningitis and septicemia with group JK Corynebacterium species in a leukopenic patient is reported. The strain was susceptible to rifampicin and vancomycin only. The finding of diphtheroids in bacteriological samples from immunocompromised patients should not be ignored. The literature regarding meningitis caused by diphtheroid bacilli is reviewed.

Adult↗
PubMed1983

Cefotaxime versus ampicillin, methicillin and netilmicin in combination for treatment of febrile episodes in patients with haematologic malignancy.

A prospective, randomized trial comparing treatment of 61 febrile episodes with cefotaxime (CTX) versus a combination of ampicillin, methicillin, and netilmicin (AMN) was carried out in 58 patients with leukaemia or malignant lymphoma, of whom 28 had a granulocyte count of less than or equal to 500 X 10(6)/l. The overall response frequency was 63% for CTX against 49% for the AMN combination, the latter figure being lower than generally reported in the literature. The difference was not statistically significant. In 21 episodes pathogens were isolated, 16 of them from the blood. All isolated bacteria but one, a strain of Bacteroides fragilis, were fully sensitive to at least one of the three antibiotics in the combination, and all but one, a strain of Listeria monocytogenes, were fully sensitive to CTX. These results indicate that CTX seems to be a promising alternative as monotherapy for empiric treatment of febrile episodes in patients with haematologic malignancies. Further investigations will, however, be required before completely rational choices between mono and combination therapy of febrile episodes in immunosuppressed patients can be made.

Adolescent↗
PubMed1983

The survival of anaerobic bacteria at 4 degrees C and 22 degrees C on swabs in three transport systems. Statistical evaluation by application of a variance component model.

The survival of anaerobic bacteria on swabs in three transport systems at 4 degrees C and 22 degrees C was evaluated. The transport systems were a charcoal-impregnated cotton swab in modified Stuart's transport medium (MS), a plain cotton swab in a dry aerobic tube (DA) and a plain cotton swab in an aerobic agar tube (AA). The test strains were Bacteroides fragilis, B. melaninogenicus ss. intermedius, Fusobacterium necrophorum, Peptostreptococcus anaerobius, Eubacterium lentum and Clostridium ramosum. Inoculated swabs were kept at the described conditions for time periods ranging from 22 1/2 min through 32 d, after which surviving organisms were recovered quantitatively. Results were described by the survival rate, defined as the percentage of organisms initially present, that had survived storage for 24 h. The survival rate was uniformly higher at 4 degrees C than at 22 degrees C. In Stuart's transport medium at 4 degrees C the survival rate was 81.9% compared to 4.3% in dry aerobic tube at 4 degrees C. At 22 degrees C the survival rate in dry aerobic tube and aerobic agar tube was 0.003% or less whereas in Stuart's transport medium growth occurred with B. fragilis, E. lentum and C. ramosum.

Anaerobiosis↗
PubMed1983

The recovery of anaerobic bacteria from swabs in three transport systems. Statistical evaluation by application of a variance component model.

The recovery of six anaerobic species from swabs in three transport systems was quantitatively evaluated. The test strains were Bacteroides fragilis, B. melaninogenicus ss. intermedius, Fusobacterium necrophorum, Peptostreptococcus anaerobius, Eubacterium lentum, and Clostridium ramosum. The transport systems were a charcoal-impregnated cotton swab in modified Stuart's transport medium (MS), or a plain cotton swab in either a dry aerobic tube (DA) or an aerobic agar tube (AA). Swabs were charged with a known number of organisms of the test strain and inserted in the appropriate transport systems. Immediately hereafter the swabs were transferred to glass tubes with reduced buffer. After vigorous shaking, aliquots from the buffer were seeded onto blood agar plates, and the number of colony forming units (CFU) was counted after incubation. The number of CFUs from independent replications had a variation that was too large to be accounted for by the Poisson distribution. The probability of recovery (POR) was defined as the number of CFU recovered from a swab as a percentage of the original inoculum. The logarithms of the POR values were analyzed with a variance component model. This showed that estimated values of POR were significantly higher in DA (44%) than in AA (23%), while the value for MS (33%) did not differ significantly from those for AA or DA. It is concluded that in MS, friction between swab and medium does not contribute significantly to bacterial recovery loss, as compared to AA and DA.

Anaerobiosis↗
PubMed1982

Bacteriuria caused by Acinetobacter calcoaceticus biovars in a normal population and in general practice.

A total of 14 strains of Acinetobacter calcoaceticus biovar anitratus and 93 strains of A. calcoaceticus biovar lwoffi from a total of 97 patients participating in studies of significant bacteriuria were cultured. These studies involved an interview survey of asymptomatic significant bacteriuria and a multiple-center investigation of urinary tract infection diagnosed in general practice. Antibiotic susceptibilities of the strains as determined by a disk diffusion technique were generally in agreement with the results in the available literature, although we found high activity exhibited by ampicillin, cephalosporin, chloramphenicol, erythromycin, and streptomycin. The following resistance patterns were seen. (i) The strains from the interview survey were more often resistant to ampicillin, oxacillin, and tetracycline than were strains from the general practice study. (ii) More biovar anitratus strains than biovar lwoffi strains were resistant to chloramphenicol, erythromycin, and mecillinam. (iii) More biovar anitratus strains than biovar lwoffi strains were resistant to carbenicillin in the interview survey. The literature relevant to the incidence and significance of A. calcoaceticus biovars in urinary cultures, as well as predisposing factors, was reviewed. The incidence of these organisms in significant bacteriuria seems to be increasing. We concluded that A. calcoaceticus biovars can cause urinary tract infection in abnormal hosts as well as in basically healthy individuals.

Acinetobacter↗
PubMed1982

Comparison of two methods for very low density and low density lipoprotein cholesterol determination.

It is shown that VLDL-cholesterol cannot be calculated from serum triacylglycerol at elevated triacylglycerol concentrations (above 2 g/l). Using the method of Friedewald et al. ((1972) Clin. Chem. 18,499-502), VLDL-cholesterol is usually overestimated in these sera and, consequently, LDL-cholesterol underestimated. Quantitative lipoprotein electrophoresis according to Wieland & Seidel ((1979) Innere Medizin 5,290-300), on the other hand, yields VLDL-cholesterol values which correspond to ultracentrifugation data within narrow limits, even in sera with high triacylglycerol contents. A nomogram has been developed for the evaluation of electropherogram.

Chemical Precipitation↗
PubMed1981

The dsRNA motif in interferon induction.

A dynamic recognition process is proposed for the triggers of interferon induction. It might account not only for dsRNAs but also for a more general dsRNA-type recognition motif, created by various low-- and high-molecular-weight nucleic acid effectors.

Interferon Inducers↗
PubMed1980

Effect of temperature, humidity and exposure to oxygen on the survival of anaerobic bacteria.

The relative effect of humidity, temperature and exposure to oxygen on the survival of 11 strains of Bacteriodes spp., Fusobacterium necrophorum, Eubacterium lentum, Clostridium ramosum, Peptococcus asaccharolyticus and Peptostreptococcus anaerobius was evaluated. Suspensions of the test strains were applied to membrane filters either in empty sterile petri dishes or on plates of non-nutrient agar to provide dry or moist conditions. The filters were stored aerobically or anaerobically in an atmosphere containing 10% CO2 at either 4 degrees C or 35 degrees C. After holding periods of 0.375-384 h, the filters were transferred to nutrient plates inside an anaerobic glove box. After incubation the growth on the filters was compared with that on control filters that had not been stored. Survival was better at 4 degrees C than at 35 degrees C. For the gram-negative organisms, survival was better under moist than under dry conditions, whereas for gram-positive organisms this finding was sometimes reversed. The results indicate that, generally, anaerobic bacteria kept under aerobic conditions survive best under moist conditions at 4 degrees C.

Anaerobiosis↗
PubMed1979

Macrophage-related suppressor cells in human renal transplant recipients.

In this study 66 renal transplant recipients were studied by in vitro immunologic monitoring assays in an attempt to delineate some immune reactivity parameters which migh explain the successful long-term survival of HLA incompatible allografts. Ninety percent of the recipients were found to be responsive to their specific donors in one-way mixed lymphocyte culture assays, indicating the presence of antigen reactive proliferating T cells. In contrast, studies of the in vitro generation of cytotoxic T cells showed that 73% of the long-term recipients demonstrated a marked hyporesponsiveness to the donor in cell-mediated lympholysis (CML) assays. Longitudinal studies indicated that specific CML hyporesponsiveness to the donor developed after transplantion. In the majority of recipients, CML hyporesponsiveness could be related to a suppressor cell phenomenon, since recipient mononuculear cells specifically suppressed the CML reactivity of third-party cells to the donor. Recipient CML hyporesponsiveness to the donor could be abrogated by removal of recipient adherent cells, most of which were monocytes or macrophages. The suppressor cell effect on CML is postulated to be related to macrophages which are either acting independently or under the regulation of suppressor T cells. These studies are among the first to suggest that suppressor cell regulation of relevant effector T cell activity may be important in the facilitation of successful human renal transplantation.

Cell Adhesion↗