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D Keller

Publications and source records attributed to D Keller.

At least 73 records · Page 4Linked to original sources
PubMed1982

Immunological relationship among human adenoviruses of subgenus D.

Antigenic relationships between adenoviruses of subgenus D were determined by neutralization tests in HeLa cell cultures by CPE inhibition. For cross-testing, several antisera of the same species were tested against the prototype viruses. 39 wild strains belonging to 12 different virus species were also studied. Marked variation in the degree of cross-neutralization between individual sera of the same species was often observed. However, virus strains within a species mostly showed identical serological reactions. Hence, antigenic specificity appears to be a fairly constant property of any one species. Strong cross-neutralizations between species are presumably due to a relationship of the hexon (hexon) antigen, whereas weak cross-neutralizations found between viruses related by hemagglutination-inhibition are due to the gamma (fiber) antigen. Viruses related to adenovirus 15 (Mastadenovirus h 15) showed a variety of cross-reactions in neutralization tests. In view of the new species definitions of adenoviruses and to facilitate identification, changes in the classification of Ad 15, 25, 29, and 15/H9 are proposed. The prototypes of Ad 13, 15, 25, 29, and 30 have been cloned by terminal dilution.

Adenoviruses, Human↗
PubMed1982

[Virological diagnosis of ocular adenovirus infection].

For laboratory diagnosis, virus isolation and identification from conjunctival swabs should be combined with serology (two blood specimens: early and 14 days or later after onset of disease). The group-specific complement fixation fails in almost one-half of the cases. Additional type-specific reactions (neutralization, hemagglutination inhibition, type-specific complement fixation) may be performed with adenovirus 8 and, in epidemic outbreaks, also with other types. Immunofluorescence procedures have proved to be of limited value; rapid diagnostic procedures are not yet available.

Adenoviridae Infections↗
PubMed1981

Adenovirus 37: identification and characterization of a medically important new adenovirus type of subgroup D.

A new human adenovirus has been isolated from 62 eyes with (kerato)conjunctivitis and from nine genitourinary sites. The virus is closely related in haemagglutination inhibition tests to adenovirus type 19 (Ad 19) and Ad 10. Antiserum adsorption experiments demonstrated the presence of three haemagglutinin antigens in the virus: One unique, another common to Ad 19, and a third common to Ad 10 and 19. In neutralization tests, the virus is distantly related to Ad 13, 30, 19, and 10. Despite this relationship, it is proposed to call the virus adenovirus 37, in agreement with current species definitions. It belongs to subgroup D of human adenoviruses. Antisera to the new virus show virtually no neutralization of other human adenovirus types. Only bay use of this antiserum it is in practice possible to avoid wrong or indefinite typing, which has often occurred in the past.

Adenoviruses, Human↗
PubMed1980

Isolation of mRNA from bovine pituitary. The cell-free synthesis of the alpha and beta subunits of luteinizing hormone.

RNA derived from bovine steer pituitary was translated in wheat germ cell-free extracts containing [35S]methionine. Antisera generated against purified denatured alpha and beta subunits of lutropin were used to demonstrate the synthesis of both proteins in vitro. The immunoprecipitated products of the cell-free system were resolved on sodium dodecyl sulfate/polyacrylamide gels and it was observed that the molecular weight of the immunoprecipitated alpha subunit protein was approximately 14,000, while that of the beta protein was estimated to be 16,000. Since the molecular weights of authentic alpha and beta subunits are 10,600 and 14,000 respectively, the cell-free products presumably represented their pre-protein forms. The ratio of the immunoprecipitated subunit pre-proteins was dependent on the magnesium concentration in the translation mixtures; at 2.1 mM, translation of lutropin alpha and beta mRNAs was comparable. RNA isolated from cow pituitary tissue directed the synthesis of fivefold less of the alpha and beta immunoprecipitated proteins than did steer RNA. Since the blood levels of gonadal steroids are higher in the cow, the results supported the hypothesis that lutropin alpha and beta mRNA biosynthesis is repressed by these steroids. The data also suggest that synthesis of lutropin alpha and beta subunits is coordinately expressed in certain physiological situations.

Animals↗
PubMed1980

[Post-operative superior mesenteric arterio-venous fistulas. A report on one case (author's transl)].

Presentation of a particularly evoking case of a post-opérative superior mesenteric arterio-venous fistula revealed by recurrent intestinal hemorrhages, diagnosed by selective arteriography and treated by resection of the anevrysmal pouch and the adjacent bowel. Review of the literature concerning 25 other cases from which it can be concluded that the digestive angiography was the only complementary examination that allowed the diagnosis. The curative surgical treatment has a 15% mortality rate in relation with hemorragic recurrences.

Adult↗
PubMed1978

Relationship of human adenoviruses 12, 18, and 31 as determined by hemagglutination inhibition.

Adenoviruses 12 and 31, but not Ad18, agglutinate rat blood cells at high titer, providing suitable blood cells be available and a prolonged contact period of virus with the erythrocytes is allowed. Purified virus particles show direct, and virus-free supernatants show direct and indirect, hemagglutination, ie, enhancement of HA by heterologous antiserum. Hemagglutination inhibition with rabbit antisera shows cross-reactions between Ad12 and Ad31 with titers 4--32 times lower than with homologous antigens; Ad18 antisera react with antigens from both of the other serotypes. No cross-reactions were seen with antisera from other adenoviruses. This suggests an antigenic relationship of the three viruses of subgroup IV in their fiber antigen gamma, in addition to the known relation in the hexon (epsilon), which is apparent in cross-neutralization.

Adenoviruses, Human↗
PubMed1977

Cholinergic blockade in reactive hypoglycemia.

The effects of cholinergic blockade on the plasma glucose and insulin responses during oral and intravenous glucose administration were studied. Propantheline (30 mg.) was given by mouth 45 minutes before standard glucose tolerance testing to produce symptomatic chollinergic blockade. In 10 normal subjects a flattening of the over-all plasma glucose response to oral glucose was observed compared with the control test, whereas insulin secretion was not different. In seven patients with repeated episodes of symptomatic reactive hypoglycemia, cholinergic blockade eliminated both symptomatic and chemical hypoglycemia in each, raising the mean nadir glucose from 44 +/- 4 mg./dl. to 84 +/- 8 mg./dl. (p less than 0.01) and significantly reducing insulin secretion. In contrast, following intravenous glucose challenge, cholinergic blockade produced no significant difference in the rate of glucose utilization or insulin secretion in either group. These results are compatible with the hypothesis that excessive vagal stimulation may contribute to the hypoglycemia seen in patients with reactive hypoglycemia but suggest that the predominant effect is on the gastrointestinal tract rather than on pancreatic islets directly. These studies confirm that anticholinergic drugs may be useful adjuvants in treating these patients.

Adult↗
PubMed1976

Laboratory procedures in adenoviruses. III. Sensitivity and specificity of serological tests (author's transl).

84 paired sera from patients with adenoviral infections were tested in neutralization and hemagglutination-inhibition (HI) against the homologous as well as against heterologous virus types of the respective subgroup. Only titer rises are considered as positive reactions. Sera of patients being infected with adenoviruses of subgroup I viruses (52 pairs, types 7, 3, 4, 14) exhibit high rates of positive reactions in the group-specific complementfixation (CF) and in homologous neutralization, lower rates in homologous HI. On the other hand, heterologous reactions are seen more frequently in neutralization than in HI. Patients with type 4 infections often show antibody responses with viruses of subgroup III (types 1, 2, 5, 6). In infections with these virus types, homologous antibody response is seen in approximately half of the cases only; heterologous reactions are observed rarely. Patients with type 8-infections (25 pairs) almost invariably show positive homologous neutralization, while HI or CF tests often fail to show rising titers. These patients, as well as 2 patients with type 19-infection, exhibit a remarcable high rate and range of cross-reactions in neutralization as well as in HI with numerous types if subgroup II and, to a lesser extent, with viruses outside of subgroup II. Although the relatively late appearance of type-specific antibodies (usually between the 10 th and 14 th days after onset of disease) is advantageous for the demonstration of antibody rises, the type-specific diagnosis of adenoviral infections should preferably be performed by isolation and typing of the virus. The heterologous reactions appear to be based on the presence of overlapping intertypic antigenic determinants rather than on an anamnestic antibody response.

Adenoviridae Infections↗