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Biomedical subjects

E Pfeiffer

Publications and source records attributed to E Pfeiffer.

At least 19 recordsLinked to original sources
PubMed1990

Comparative tumorigenicity of picene and dibenz[a,h]anthracene in the mouse.

The carcinogenic activity of the two polycyclic aromatic hydrocarbons (PAHs), picene (benzo[a]chrysene) and dibenz[a,h]anthracene (DBA), was determined in NMRI mice by five different experimental protocols in order to find out if picene is a carcinogen as predicted by recent quantum mechanical calculations in contrast to earlier observations which could not confirm any carcinogenic activity of picene. Single s.c. treatment of adult mice with picene or DBA (308 nmol/animal, each) led to the formation of fibrosarcomas in 63.3% of treated animals regardless of the PAH used. Chronic epicutaneous application of both PAHs (total dose 1.36 mumol) to the back of mice resulted in the development of papillomas with a tumor rate of 22% in the case of picene and of 32% in the case of DBA. When newborn mice were s.c. treated once on day 2 of their life with each of the two PAHs (400 nmol/animal), 27.8% of treated animals developed lung adenomas after 40 weeks in the case of picene compared to 92.1% in the case of DBA. Histopathological examination of the tumors in the three experimental models revealed no difference in the type of tumor between picene and DBA. Epicutaneous application of both PAHs (600 nmol/animal) followed by chronic treatment with 12-O-tetradecanoyl-phorbol-13-acetate for 24 weeks led to the formation of papillomas in 93% of animals treated with DBA while picene showed no tumorigenic activity at all. Initiation of tumorigenesis in the two-stage tumor model with 7,12-dimethylbenz[a]anthracene (1 mumol/animal) and chronic treatment with picene (total dose 4.8 mumol) for 24 weeks was equally ineffective in producing tumors in NMRI mice. This rare biological property of picene, which is a complete carcinogen, yet at most a very weak tumor initiator, is explained in terms of its inefficient biotransformation to mutagenic and carcinogenic metabolites as compared to the strong tumor initiator DBA.

Animals↗
PubMed1989

Comparative studies of conversion disorders in childhood and adolescence.

In a syndrome validation study, four groups of patients suffering from conversion disorders, anxiety states, obsessive-compulsive disorder and emotional disorders, as well as a healthy control group, were compared. The following findings emerged: besides female preponderance and greater age, a higher rate of low SES subjects and social migration patients suffering from conversion disorders displayed a greater proportion of psychiatric and medical diseases in their parental heritage.

Adolescent↗
PubMed1988

Polyclonal IgG synthesis of mononuclear cells induced by the homopolymer of 4,6-dideoxy-4-formamido-alpha-D-mannopyranosyl units isolated from Brucella melitensis.

Brucella melitensis attaches selectively to B lymphocytes. The bacterium induces in vitro only a slight proliferation of mononuclear cells and inhibits the spontaneous IgG synthesis. In order to characterize these effects, the O-chain of the lipopolysaccharide of Brucella melitensis (a polysaccharide consisting of poly-4,6-dideoxy-4-formamido-alpha-D-mannoside) was prepared and its influence on lymphocyte functions tested. This compound had no effect on blast transformation whereas IgG synthesis of the cells was stimulated more than tenfold by the addition of the Brucella polymannoside.

Antibody Formation↗
PubMed1979

Treatment modalities in the affective disorders of old age.

In summary, I have reviewed the application of three major treatment modalities, psychotherapy, drug therapy, and electroconvulsive therapy, to the affective disorders of old age. Older patients are remarkably responsive to each of these forms of psychotherapy. Certain modifications in therapeutic approach must be introduced to make them effective. However, once these modifications are implemented many older patients can return to normal and satisfying lives following effective treatment of their affective disorders.

Affective Symptoms↗
PubMed1979

[Travellers' diarrhoea. I. Field study on frequency and causes in German tourists (author's transl)].

Even after successful localization of dangerous epidemics, infectious diseases represent a troublesome accompaniment of growing tourism to warm countries. Classical pathogens of diarrhoea are subjected to a worldwide control network to prevent this disease at least from being spread. Close surveillance has shown that, additionally, less clearly defined pathogens exist which affect a high percentage of tourists and cause a usually harmless but nevertheless often very annoying diarrhoea. In a tropic insular state a field study was carried out with voluntary assistance of German flight passengers in order to investigate the qualitative and quanitative importance of travellers' diarrhoea and to supplement American observations mainly gained in Mexico. In a first study we found that pathogens were detected only in six out of 173 stool samples: the pathogens were Salmonellae which had caused clinical symptoms in two cases only. With respect to diarrhoea with different origin which affected some 20 per cent of our examinees we will inquire into the importance of E. coli as pathogen, which is generally classified harmless but liable to interfere considerably with holidays and recreation.

Diarrhea↗
PubMed1978

[Use of flocculants for detection of viruses in fluids (author's transl)].

Hydroxide flocs of iron, aluminium, zinc, and tin were tested for their capabilities of virus enrichment in fluids (such as water and liquid foods). The virus used was polio type II att. The flocculation with tin yielded the best results because it gave the highest recovery rates (90%) and good reproducibility. A satisfactory enrichment was also obtained with the flocculation with aluminium- and iron salts. The losses were 31 and 33%. The lowest recovery rates were obtained with nickel- and zinc flocculation (losses: 70 and 77%). The difficulties in filtering the flocs and eluting the virus with 3% beefextract could be overcome by centrifugation and dissolution of aluminium and iron flocs with sodium-potassium-tartrate (average recovery rates 5 and 27%). In addition we tested the flocculation in lemonade as a model fluid loaded with a high content of organic material which usually interfere with the formation of flocs and in consequence the enrichment of viruses. An enrichment of viruses in lemonade was possible only with previously prepared and aged flocs of tin and iron. The loss was 18 and 12% respectively.

Aluminum↗
PubMed1976

19. Generic services for the long-term care patient.

The purpose of multidimensional functional assessment of the long-term care patient or client is to identify the relevant set of services or service package. This necessitates defining the universe of services independently of existing service providers and settings, which vary considerably in scope and type of activities. A list of 24 generic services developed by the Duke Center for the Study of Aging and Human Development has proved useful in assigning patients to the appropriate providers. It is also a means of describing accurately the service capacity of a given program or institution, as well as the precise nature of the intervention, or set of services, in studies of impact or outcome. Planners and evaluators can use the list to cost existing programs and to plan new ones more responsive to the requirements of long-term care patients and clients.

Aged↗