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Biomedical subjects

K Wicher

Publications and source records attributed to K Wicher.

At least 91 records · Page 5Linked to original sources
PubMed1976

Cellular and humoral immune response to guinea pig infected with Treponema pallidum.

Guinea pigs infected intradermally with Treponema pallidum Nichols strain were examined for the presence of lesions and for cellular and humoral response. Of the 26 guinea pigs (77%) demonstrated darkfield positive lesions between 6 and 20 days after infection. Animals divided into six groups of 4-5 in each were sacrificed between 2 and 24 weeks. The peritoneal exudate cells, obtained 4 days after injection of oil, were examined by the direct and the cells from lymphoid organs by the indirect capillary leukocyte migration method in the presence of 10 and 30 mug/ml of Reiter antigen. The peritoneal exudate cells responded with enhancement of leukocyte migration, reaching significant values between 6 and 24 weeks after injection. The cells from the lymphoid organs showed enhancement of leukocyte migration until the 4th week of infection. Treponemal antibodies, found in all animals, started to appear at the 4th week reaching a maximum titer at the 12th week after infection. The appearance of the antibodies correlated well (p less than 0.05) with the appearance of the enhancement of leukocyte migration. Wassermann antibodies were not detected throughout the 24 weeks of infection. The unique immune responses are discussed in view of the available data concerning natural acquired and experimental syphilis.

Animals↗
PubMed1975

Laboratory experience with a radiometric method for detecting bacteremia.

Two bacteriologic systems for detecting bacteria in blood were compared; the automated radiometric BACTEC and the conventional method used in our laboratory for many years. BACTEC consisted of two bottles with 30 ml and the conventional method with 50 ml of media for aerobes and anaerobes. The BACTEC bottles were inoculated with 2 to 3 ml and the conventional with 4 to 5 ml of blood at the patient's bedside. Out of the 3,045 blood specimens cultured (804 patients), 262 (117 patients) were positive by one or both methods. The conventional system detected 5more cultures. The explanation of the differences is discussed. Positive blood cultures were detected by the BACTEC procedure as early as 6 h after the blood collection. In the first 24 h, on the average, 77% of aerobic organisms were detected by the BACTEC as compared to 48% by the conventional system. All anaerobic BACTEC cultures were positive within 4 days, whereas the conventional system detected at that time 74%. At day 4, 67% of fungi were detected by the BACTEC and only 27% by the conventional system. Of the 3,045 blood cultures examined by the BACTEC, 208 were recorded as false positive with growth index readings ranging from 30 to 59.

Aerobiosis↗
PubMed1975

Cell response in rabbits infected with T. pallidum as measured by the leucocyte migration inhibition test.

Leucocyte migration in agarose was used to examine cell response in 48 rabbits infected with the Nichols strain of T. pallidum for 1 week to 16 months. The response of the peripheral leucocytes to T. pallidum antigen (TpAg), 3 and 15 mug/ml., Reiter antigen (RAg) 6 mug./ml., and VDRL reagent 1:500 was examined. The cells in the presence of RAg, TpAg--3 mug./ml.--and the VDRL reagent demonstrated a biphasic response; in the early stage of infection (until the 4th week) stimulation of leucocyte migration and in the later stage of disease inhibition of leucocyte migration was observed. The higher concentration of TpAg--15 mug./ml.--caused only inhibition of leucocyte migration. The leucocyte response in vitro could not be confirmed by intradermal skin tests with 5 x 10(7) heat-killed T. pallidum. No correlation between the cell response and the treponemal antibodies was observed.

Animals↗
PubMed1975

In vitro reaction of antibodies to ragweed. I. Radioimmunoassay for measuring antibody levels.

A radioimmunoassay was developed in which human antibodies to ragweed compete with 125I-labeled rabbit anti-ragweed antibodies for the ragweed antigen coupled to cellulose particles. By means of this test, antibodies to ragweed were determined in 96 sera of treated and untreated patients with ragweed allergy and in 32 sera of nonallergic individuals. Within the applied experimental conditions, it was possible to measure antibodies over a range from 0.4 to 200 mug/ml. In patients receiving immunotherapy, the mean value of the antibodies was 7.2 mug/ml, and in the untreated patients 1.8 mug/ml. Antibodies to ragweed were also found in the sera of nonallergic individuals. It is assumed that this test measures 'total' serum antibodies to ragweed.

Allergens↗
PubMed1975

In vitro reaction of antibodies to ragweed. II. Quantitative determination of non-IgE antibodies interferring in a radioallergosorbent test.

Immunoglobulin E-rich fractions and IgE-depleted fractions were prepared from individual and pooled sera of patients allergic to ragweed. The IgE-depleted fractions contained antibodies to ragweed associated with the immunoglobulins G, A and M. The IgE-rich fraction contained only IgE antibodies to ragweed, although other immunoglobulins were present in this fraction. The amount of antibodies in these fractions was determined by the radioimmunoassay described in a preceding publication. The inhibitory role of the non-IgE antibodies was examined in an allergosorbent test (RAST) by using various concentrations of the IgE-rich fraction. The RAST was performed using ragweed-coupled cellulose powder as well as paper discs. The IgE antibodies in concentration from 0.017 to 0.069 mug/ml were inhibited by 30-60% in the cellulose RAST by non-IgE antibodies in concentrations from 6.25 to 12.5 mug/ml. The inhibition effect was substantially less pronounced in the paper disc RAST. This would indicate that for diagnostic purposes, especially for examination of sera with high levels of IgG antibodies, it is more reliable to use the disc RAST instead of the cellulose powder RAST.

Allergens↗
PubMed1973

In vitro susceptibility of Neisseria gonorrhoeae to spectinomycin examined by a broth dilution method.

The in vitro susceptibility of 113 strains of Neisseria gonorrhoeae to spectinomycin was determined by the broth dilution method and was compared with their susceptibility to penicillin and ampicillin. All strains demonstrated a susceptibility to spectinomycin in a range between 2.5 and 20 mug/ml; 96% of these strains were susceptible in a range from 5 to 10 mug/ml. The same strains were susceptible to ampicillin at concentrations between 0.06 and 0.5 mug/ml and to penicillin between 0.02 and 1.25 units/ml. For the majority of strains, the minimal inhibitory and bactercidal concentrations were identical; however, with more than 10% of the strains, the minimal inhibitory concentration was lower than the minimal bactericidal concentration.

Ampicillin↗