PubMed Health⌕ Search

Biomedical subjects

R Wahl

Publications and source records attributed to R Wahl.

At least 73 records · Page 4Linked to original sources
PubMed1990

Compilation of DNA sequences of Escherichia coli (update 1990).

We have compiled the DNA sequence data for E.coli available from the GENBANK and EMBL data libraries and over a period of several years independently from the literature. This is the second listing replacing and increasing the former listing roughly by one third. After deletion of all detected overlaps a total of 1 248 696 individual bp is found to be determined till the beginning of 1990. This corresponds to a total of 26.46% of the entire E. coli chromosome consisting of about 4,720 kbp. This number may actually be higher by some extra 2% derived from the sequence of lysogenic bacteriophage lambda and various insertion sequences. This compilation is now available in machine readable form from the EMBL data library.

Base Sequence↗
PubMed1990

Determination of IgE-specificities in nasal secretions and sera of allergic subjects by crossed radio-immunoelectrophoresis.

Allergen-specific IgE antibodies have not only been demonstrated in the serum, but also in the nasal secretions of allergic patients by means of the radio-allergosorbent test (RAST). In this preliminary study we adapted the technique of crossed radio-immunoelectrophoresis (CRIE) to nasal secretions in order to obtain further insight into the specificity of locally collected antibodies. Based on RAST results we compared CRIE patterns in serum, nasal secretions in 13 out of 23 grass pollen allergic subjects and two out of three house dust mite allergic subjects. In the nasal secretions the same IgE specificities were found as in the corresponding serum of the individual subject and as in a reference serum pool. These data indicate that the same specificity of IgE antibody can be found in the serum and the target organ. From these data there is no evidence for a local mucosal immune response that differs in specificity from the serum response.

Animals↗
PubMed1990

Influence of thyroid hormones and catecholamines on myosin of swim-exercised rats.

To define the physiological signals involved in the redirection of myosin expression in the swim-exercised rat, the relative influence of thyroid hormones and beta-adrenergic blockade was determined. Swimming exercise resulted in an increased proportion of myosin V1 (60.9 +/- 9.7 vs. 38.0 +/- 4.1% of sedentary rats fed ad libitum) but did not increase serum concentrations of total and free thyroxine or triiodothyronine determined either 17-21 h or immediately after swimming. The proportion of V1 increased, although intermittently food-deprived rats with the body weight of swimming rats exhibited a reduced proportion of V1 (23.5 +/- 2.7). When swimming rats had only intermittent access to food, they had reduced concentrations of all thyroid hormones, but the proportion of V1 (51.5 +/- 7.6) was nonetheless increased. Thus the redirection of myosin expression cannot be attributed to an increased secretion of thyroid hormones. The influence of the adrenergic system was assessed by treating swimming rats with the beta-blocking drug atenolol. Because the proportion of V1 was reduced, but thyroid hormones were not affected, beta-adrenergic blockade seems to influence myosin expression independently of thyroid hormones.

Animals↗
PubMed1990

IgE-mediated allergic reactions to potatoes.

We investigated sera of 12 patients with IgE-mediated hypersensitivity reactions to potato, using different in vitro methods. Radioallergosorbent test classes 2-4 (7.6-46.5% binding) were measured with potato allergen disks. Immunoblot detected allergen bands with an isoelectric point range of approximately 4.5-5.2 and mainly in a molecular weight range between 16.00 and 30.00 kD. But also at molecular weights of 43.00 and 65.00 kD allergen bands (IgE specificities) could be detected. Histamine release assay performed with isolated fractions of the potato extract showed a great individual variation and positive results of fractions of molecular weights between 10.00 and 80.00 kD. From our data we conclude that raw potato is a 'multiallergenic' vegetable.

Adolescent↗
PubMed1990

Allergens of horse epithelium. I. Physicochemical and immunochemical characterization of five different horse epithelium raw materials used for allergen extract preparation.

We investigated five horse epithelial allergen extracts prepared from different qualities of raw material by several biochemical and immunochemical methods. Horse serum albumin and horse serum were used to identify serum-related antigens. We found high similarities as well as marked differences between the extracts. There were strong differences in the protein contents, the protein patterns obtained by isoelectric focusing and sodium dodecyl sulfate polyacrylamide gel electrophoresis, the total allergenic activities obtained by radioallergosorbent test inhibition assays and the amounts and numbers of serum-related proteins. The patterns of dander-related allergens in crossed radioimmunoelectrophoresis were similar but showed partly strong differences in allergen concentrations. Allergen compositions determined by blotting methods showed only minor differences between the investigated epithelial extracts. It appears that some of the differences, e.g. the content of serum-related proteins, depend on the way the different raw materials are prepared. Because serum-related extract components are not considered as major allergens, their content should be low in horse epithelial allergen extracts. For this reason whole skin cannot be recommended as starting material for horse epithelium allergen extract preparation.

Allergens↗
PubMed1989

Comparison of in-house allergen extracts of Phleum pratense (timothy grass) pollen with the international standard and investigation of IgE specificities of a grass-pollen serum pool from West Germany and of the one recommended by the World Health Organization.

We compared our in-house reference extract (RE) and a production extract (PE) with the international reference preparation (IRP) of International Union of Immunological Societies of timothy-grass pollen, using various biochemical and immunochemical methods. Furthermore, we compared the IgE composition of our in-house grass-pollen serum pool (West Germany) with the serum pool recommended by the World Health Organization, using the RE for crossed radioimmunoelectrophoresis (CRIE). Our extracts (RE and PE) were nearly comparable with the IRP. Only by CRIE one more allergen could be detected in RE and PE than in IRP and in another extract purchased from an American company. This finding may depend on the region where the source materials were harvested and which source materials were used for the preparation of the extracts. Furthermore, by high-performance liquid chromatography in the low-molecular-weight range, two distinct peaks could be detected in the nondiafiltered IRP, which were detected in the diafiltered RE and PE as traces only. The IgE composition of our in-house grass-pollen serum pool was comparable with the serum pool recommended by the World Health Organization, as detected by CRIE using RE.

Allergens↗
PubMed1989

Double-blind, placebo-controlled immunotherapy with mixed grass-pollen allergoids. III. Efficacy and safety of unfractionated and high-molecular-weight preparations in rhinoconjunctivitis and asthma.

Specific immunotherapy with unmodified formalinized allergoids is effective in grass-pollen allergy, but systemic reactions have been observed. A high-molecular-weight formalinized allergoid (HMW-GOID) was fractionated by gel filtration, retaining molecules of greater than 85,000 daltons in the expectation of improving safety without sacrificing efficacy. HMW-GOID and unfractionated allergoid (GOID) had a similar allergenic activity assessed by RAST inhibition, but the HMW-GOID preparation was 65 times less reactive when it was tested by skin prick test than the GOID preparation. A double-blind, placebo-controlled study was carried out in grass pollen-allergic patients with placebo (14 patients), GOID (15 patients), and HMW-GOID (13 patients). An additional group of 18 patients was treated by a rush schedule with a standardized orchard grass-pollen extract. A similar mean cumulative dose was administered with both allergoids. The fractionated allergoid only elicited minor systemic reactions similar to reactions elicited by placebo, whereas 20% of patients treated by GOID and 5.5% of patients receiving the standardized extract had a severe systemic reaction. For rhinitis, conjunctivitis, and asthma, the HMW-GOID and the standardized extract had a similar efficacy, significantly greater than placebo. GOID was less effective than the other two active treatments but was significantly more effective than placebo treatment for asthma and conjunctivitis.

Adolescent↗
PubMed1989

IgE-mediated allergic reactions to fruit gums and investigation of cross-reactivity between gelatine and modified gelatine-containing products.

A 32-year-old female reacted with a contact urticaria syndrome after eating 'gummy bears' (fruit gums). The reaction began in the oral mucosa and led to treatment on an inpatient basis. RAST measurements with allergen discs produced with gelatine and gelatine-containing products (among them 'gummy bears') demonstrated the presence of IgE antibodies in the serum of this patient. Proteins with molecular weights in the range of 40-120 kD were identified as the allergens in gelatine by using Western blot analysis. RAST inhibition showed cross-reactivity between gelatine, gelatine-containing products and the modified gelatine used in some plasma substitutes. Allergic reactions towards coloured fruit candies and 'gummy bears' may result from an IgE-mediated hypersensitivity towards gelatine. The long-known anaphylactoid reactions towards gelatine-containing plasma substitutes may, at least in part, be of an allergic nature.

Adult↗
PubMed1989

Investigation of the allergenic activity of isolated fractions of a standardized partly purified whole mite body (Dermatophagoides pteronyssinus) extract.

Twelve fractions of a molecular weight range of 1.35-670.00 kilodaltons (kD) were isolated from a biologically standardized partly purified whole mite body extract (Dermatophagoides pteronyssinus) by preparative size exclusion high-performance liquid chromatography. The allergenic activity and the antigen and allergen patterns of the isolated fractions were investigated by RAST, RAST inhibition and crossed (radio)immunoelectrophoresis (CIE/CRIE). By CRIE, each of the fractions showed allergen patterns, mostly of different compositions. Each fraction showed allergenic activity of different degrees by RAST inhibition. The highest allergenic activity could be measured by RAST inhibition with fractions which contained predominantly the major allergens Der pI and PY as detected by CRIE. Also proteins of higher molecular weights (greater than 158 kD) showed IgE-binding capacities. Nearly all antigens detected by CIE could be identified as allergens using CRIE.

Allergens↗
PubMed1989

Effects of human thyroxine-binding globulin and prealbumin on the reverse flow of thyroid hormones from extravascular space into the bloodstream in rabbits.

A plasma fraction rich in thyroid hormone-binding globulin (hTBG, human thyropexin) was injected iv into rabbits in order to see whether thyroid hormone concentrations in plasma would increase by return of T3 and T4 from the extravascular space. For this purpose, both [125I]T3 and [131I]T4 were simultaneously injected. After 1 h, or after 16 h in another series of experiments, 50 mg hTBG were injected iv. Thereafter, the mean radioactivity of both [125I]T3 and [131I]T4 in the plasma rose, and reached its peak 20-30 min after hTBG injection; [125I]T3 and [131I]T4 returned to the preinjection value slowly, after more than 3 h. When hTBG was injected 15-16 h after the radioactive hormones, the mean radioactivity of [125I]T3 reached its peak about 1 h after hTBG injection and returned to the base value after approximately 5.5 h, [131I]T4 reached its peak about 1 h after hTBG injection and returned to the base value within 12 h. After injection of hTBG, total T4 and T3 concentrations in plasma increased about 3- to 5-fold over the base values. At the same time, the percentage of both, free T4 and free T3 dropped instantly whereas absolute free T4 and free T3 values remained almost constant. After injection of 500 mg transthyretin (hTBPA), a similar flux of [125I]T3 and [131I]T4 was observed, whereas 500 mg human serum albumin were ineffective. These marked effects of injected hTBG and hTBPA on the serum levels of [125I]T3, [131I]T4, and total T3 indicate that reentry of T3 and T4 into the intravascular compartment is an important component of thyroid hormone distribution and transport. As can be anticipated from the animal experiments, the efficiency of plasmapheresis or hemofiltration methods may be improved by previous application of large doses of hTBPA or hTBG in cases of thyrotoxicosis.

Animals↗
PubMed1989

Comparison of Alternaria tenuis extracts prepared from different raw materials.

Alternaria extracts, prepared from three different sources under the same conditions, were compared by several biochemical/immunochemical methods. Two raw materials (A,G) contained mostly mycelia. The third raw material (C) contained mycelia (35%) and spores (65%). Extracts A and G were different in total allergenic potency, antigen/allergen pattern, and in the Alt 1 content. Extract C was of similar total allergenic potency as extract A but showed a somewhat different antigen/allergen pattern and a different Alt 1 content. Although there were some compositional differences among the extracts, all extracts regardless of source materials (spores and mycelia) demonstrated strong RAST inhibition activity and parallelism of the inhibition curves.

Allergens↗
PubMed1989

(Radio) rocket immunoelectrophoresis a useful screening method for house dust extracts.

House dust (HD) extracts prepared from HD collected in households from West Germany, USA, and Spain were investigated by (radio) rocket immunoelectrophoresis. By pouring agarose gels containing different antisera side by side in strips onto a glass plate, the antigen/allergen components of HD extracts could be detected simultaneously in one electrophoretic separation. In addition to mite and animal dander, antigens/allergens of pollens, mold and food (ovalbumin and cow serum) could be detected in most of the extracts.

Allergens↗
PubMed1988

T-cell lymphomas containing Epstein-Barr viral DNA in patients with chronic Epstein-Barr virus infections.

Fatal T-cell lymphomas developed in three patients with a chronic illness manifested by fever, pneumonia, dysgammaglobulinemia, hematologic abnormalities, and extraordinarily high titers of antibody to the Epstein-Barr virus (EBV) capsid antigen (greater than 10,000) and early antigen (greater than 640) but low titers to the EBV nuclear antigen (less than or equal to 40). To understand the pathogenesis of these tumors better, we determined the immunophenotype of the tumor cells and analyzed tumor-cell DNA for EBV genomes and for lymphoid-cell gene rearrangements. More than 80 percent of the cells in tumors had an activated helper T-cell phenotype (T4, T11, la positive). The EBV genome was found by in situ hybridization in tumor tissue from each patient. Southern blot assay of DNA digests from one patient showed the same pattern as that of the EBV-infected marmoset line, B95-8. DNA digests from two patients showed a monoclonal proliferation of T cells determined on the basis of uniform T-cell-receptor gene rearrangements and a single band for the joined termini of the EBV genome. We conclude that EBV may infect T cells and contribute to lymphomas in selected patients with severe EBV infections.

Adult↗
PubMed1988

Double-blind, placebo-controlled immunotherapy with mixed grass-pollen allergoids. II. Comparison between parameters assessing the efficacy of immunotherapy.

Specific immunotherapy is effective in alleviating symptoms in grass pollen-induced rhinitis, but there are no clear data demonstrating a correlation between symptom-medication scores and objective parameters. Twenty-five patients taking part in a double-blind, placebo-controlled immunotherapy with mixed grass pollen-formalinized allergoids were studied. All patients had the same investigations. Symptom-medication scores were significantly (p less than 0.005, Mann-Whitney U test) reduced in the treated group by comparison to the placebo-treated patients. Nasal challenges performed with threefold increasing numbers of orchard grass-pollen grains demonstrated that patients treated with allergoid tolerated a significantly (p less than 0.005, Wilcoxon W test) greater number of grains after treatment, whereas there was no mean difference in the placebo-treated patients. There was a significant (p less than 0.005, Spearman rank-correlation) correlation between nasal challenges and symptom scores during the season. The skin prick test end point was significantly (p less than 0.001, Wilcoxon W test) reduced after treatment in the allergoid-treated group and remained unchanged in the placebo-treated group. There was a significant (p less than 0.001) correlation between the skin prick test end point and symptom scores during the season. Serum grass-pollen IgG titrated by a solid-phase radioimmunoassay with Staphylococcus A protein was significantly (p less than 0.01, Wilcoxon W test) increased after treatment with allergoid, but there was no significant correlation between IgG titer and symptom scores during the season. Serum grass-pollen IgE increased (p less than 0.04, Wilcoxon W test) in the treated group but there was no correlation with symptom scores.

Adult↗
PubMed1988

Investigations of patients allergic to the house dust mite Dermatophagoides pteronyssinus by crossed radioimmunoelectrophoresis using purified mite bodies and whole mite culture extracts.

Sera of 20 patients allergic to the house dust mite Dermatophagoides pteronyssinus were investigated by crossed radioimmunoelectrophoresis (CRIE) using extracts prepared from purified mite bodies (PMB) and whole mite culture (WMC). By CRIE, different allergen patterns and different numbers of allergens were detected in the two extracts. By summarizing the values of the CRIE patterns of the 20 patients' sera into allergograms, 6 out of 16 allergens in PMB and 5 out of 10 allergens in WMC extracts could be identified as major allergens. These diverging results, together with the published literature, emphasize the necessity to reevaluate the International Standard for D. pteronyssinus.

Allergens↗