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Biomedical subjects

M Hagedorn

Publications and source records attributed to M Hagedorn.

At least 73 records · Page 4Linked to original sources
PubMed1988

The development of the jamming avoidance response in the weakly electric fish, Eigenmannia.

The jamming avoidance response (JAR) in young weakly electric fish, Eigenmannia, develops at the onset of a functional electrosensory phase-coding system, a neural pathway that is critical for the performance of the JAR. Size (measured in head to tail length) seems to be the best predictor of the onset of the JAR. A distinguishable JAR value (0.15 Hz or greater) develops in fish at a length of 12-15 mm, and its strength continues to increase with maturity until it approaches an adult value (8-20 Hz) at a length of about 45 mm. The JAR is not dependent upon social interactions, as it can be performed correctly upon first stimulation by animals raised in individual aquaria from the egg stage. Preliminary studies suggest that there are anatomical correlates to the development of the JAR behavior. As the JAR strengthens with age, there is a concomitant increase in the number of giant cells and a development of the commissural plexus in lamina 6 of the torus semicircularis. Giant cells play a pivotal role in the phase comparison circuit. Both phase and amplitude information play a role in the proper performance of the JAR, but the discrete nature of the phase comparison circuit allows the correlation between the development of the JAR and an essential part of the phase comparison circuit (lamina 6 of the torus) to be observed in Eigenmannia.

Animals↗
PubMed1987

[Torre-Muir syndrome].

The Torre-Muir syndrome is a tumour syndrome characterized by multiple cutaneous and extracutaneous primary carcinomas and different sebaceous neoplasias. The visceral adenocarcinomas are mainly found in the gastrointestinal and urogenital tract. A case of Torre-Muir syndrome is described in a female patient and the different tumour localizations are demonstrated.

Biopsy↗
PubMed1986

[Lymphomatoid papulosis--pseudolymphoma with uncertain prognosis].

On account of its distinct clinical and histological picture, lymphomatoid papulosis (l.p.) is mostly considered an entity. A 70-year-old patient with l.p. is described. Histologically, there were similarities to the granulomatous type of pseudolymphoma. The oral treatment with penicillin for 4 weeks was successful, but we cannot exclude a spontaneous remission.

Aged↗
PubMed1986

Acoustic communication in an electric fish, Pollimyrus isidori (Mormyridae).

It has been known since von Frisch's work in the 1930's that mormyrid electric fishes are quite sensitive to sound. We now describe a repertoire of natural sounds produced by the mormyrid, Pollimyrus isidori, during breeding and aggression; reception of communication sounds is probably a major function for mormyrid audition. In aquaria, Pollimyrus isidori produce 'grunts', 'moans', 'growls', 'pops' and 'hoots' at various phases during nesting, courtship, and territory defense. All five sounds are produced primarily at night. Territorial males produce grunts, moans and growls during courtship. Vocalizing is stimulated by the presence of a gravid female on the male's territory and decreases with the onset of spawning. Hoots and pops are given during agonistic behavior. Grunts are bursts of acoustic pulses, stereotyped for an individual, with the potential as individual signatures. The electric organ is silent during grunts and moans and is discharged at a reduced rate during growls. The courtship and spawning of Pollimyrus isidori is described.

Agonistic Behavior↗
PubMed1986

[Treatment of symptomatic mucinosis follicularis in mycosis fungoides using fast electrons].

Mucinosis follicularis is a chronic type of dermatosis involving the sebaceous glands and outer root sheaths, which can be differentiated into primary and secondary types. The latter - also called symptomatic mucinosis follicularis - causes therapeutic problems because of the underlying malignant lymphoma. Successful treatment using electron beams supported by etretinate is described in detail in a 40-year-old man with symptomatic mucinosis follicularis based on plaque-type mycosis fungoides. After 6 months free of skin symptoms, the mycosis fungoides lesions recurred in the overlapping borders of the irradiation fields. These lesions were treated again with electron beams. A relapse after 32 months was controlled by PUVA. Electron beam therapy is recomended in the plaque type of mycosis fungoides, especially if PUVA has no effect for some reason.

Adult↗
PubMed1986

[Borrelia-associated dermatoses].

Erythema chronicum migrans (E.c.m.), Acrodermatitis chronica atrophicans (A.c.a.) and Lymphadenosis benigna cutis (L.b.c.) are infectious diseases according to Koch's criteria, after the infectious agent-Borrelia-Burgdorferi-could could be isolated. Clinic, pathology and therapy of these three diseases are presented in detail. The correlation to the lyme disease is being discussed. We believe that E.c.m., A.c.a. and L.b.c. are different entities determined by the virulence of the infectious agent and the individual immunological response.

Acrodermatitis↗
PubMed1986

[Preventive lymphadenectomy in cutaneous malignant melanomas. A matched pair study].

Data on 70 patients with melanomas classified as clinical stage I, who had been treated surgically with wide excision (n = 49) or wide excision plus prophylactic lymph node dissection (n = 21) at the University Dermatology Clinic, Freiburg i. Br. between 1975 and 1977, were reviewed in a retrospective study. The effectiveness of elective lymph node dissection was examined by creating 21 pairs of patients, matched according to sex as well as to the level, location and thickness of the tumors (to within +/- 5%). One patient in each pair underwent wide local excision and prophylactic lymph node dissection (WE + PLND) to others did not (WE only). Depending on tumor thickness there was a better chance of survival for the PLND patient group. However, these differences were not statistically significant.

Female↗
PubMed1985

[Clinical picture and pathology of dermatofibrosarcoma protuberans].

Dermatofibrosarcoma protuberans (D.p.) is a rare connective skin tumor (0.1%). On the basis of the literature and 13 own cases, we present data concerning age, sex, localisation, as well as clinical and histological findings. We report on pre-operative planning of treatment, surgical therapy (wide excision and closure by rotation flap), and clinical course. The follow-up indicates that D.p. is a neoplasia bearing a low rate of malignancy, which may change into a highly malignant tumor especially after treatment with radiation.

Adult↗
PubMed1985

Bowenoid papulosis. Presence of human papillomavirus (HPV) structural antigens and of HPV 16-related DNA sequences.

This study reviews 39 cases of anogenital bowenoid papulosis lesions in 22 individuals of both sexes that were analyzed clinically, histologically, immunocytochemically, and virologically. Macroscopically, three different types of lesions were demonstrated: erythematous macules; papules (lichenoid and/or pigmented papules); and leukoplakialike lesions. Microscopically, bowenoid papulosis fulfills the criteria of a squamous cell carcinoma in situ. Much like oral precancers, three distinct growth patterns (flat, endophytic, and exophytic) could be differentiated, which did not correlate with the clinical aspect of the lesions. In only two (5.12%) of the 39 cases of bowenoid papulosis could structural antigens of papillomaviruses be detected immunocytochemically (peroxidase-antiperoxidase technique). The DNA from 12 lesions that were analyzed for the presence of papillomavirus-specific sequences hybridized stringently in all cases with the human papillomavirus 16 specific DNA probe labeled with phosphorus 32.

Adolescent↗
PubMed1985

Papillomavirus infection of the anogenital region: correlation between histology, clinical picture, and virus type. Proposal of a new nomenclature.

The clinical and histologic picture of 84 anogenital condylomatous and condyloma-like lesions of both sexes were analyzed in an effort to establish a correlation to the different papillomavirus (PV) types. The presence of human papillomavirus (HPV)-specific DNA sequences was confirmed through molecular hybridization and the presence of PV structure antigens was verified in thin sections by means of a group-specific anti-PV-antiserum using the peroxidase-antiperoxidase (PAP) technique. Three distinct clinical forms harboring distinct HPV types were distinguished: (1) Condylomata acuminata in which HPV-6 DNA was present in 37 of 59 samples and HPV-11 DNA in only 13 of 59 samples. HPV-16 DNA was not detected at all and 9 condylomatous lesions remained unclassified. (2) Flat condyloma-like lesions, where HPV-6 and HPV-11 were associated with lesions of low epidermal atypia in 8 and in 2 of 18 cases, respectively, and where HPV-16 was associated exclusively with 6 of 18 such lesions with severe atypia, called bowenoid papulosis. (3) Pigmented papules where HPV-16 was detected twice in lesions of bowenoid papulosis and HPV-11 in 2 of the benign pigmented lesions. The fourth clinical manifestation of genital papillomavirus infections--the so-called condylomata plana--was not available for virologic analysis. Histologically 5 different koilocytotic features were determined which could not be correlated either with one of the clinical pictures or with a specific PV type. HPV-16, however, was found frequently in non-koilocytotic lesions exhibiting the features of severe epithelial atypia known in bowenoid papulosis. The existence of PV structure antigens in these lesions could not be verified using the indirect immunoperoxidase--PAP-technique--in contrast to the koilocytotic lesions where clear evidence of the presence of HPV was proved in 36 of 56 (64.3%) of the cases.

Animals↗
PubMed1985

Epidermal growth factor receptors in different skin tumors.

Specific binding of 125I-labeled epidermal growth factor (EGF) was measured in 62 skin tumors of different severity. Within a group of 28 benign tumors, 11 of 15 condylomata acuminata were receptor positive, whereas the investigated mesenchymal tumors and normal skin as a control were receptor negative. 6 of 18 basal cell epitheliomas bound EGF specifically. In the group of precancerous and malignant skin tumors, 7 of 8 squamous cell carcinomas had the highest number of EGF binding sites and a high affinity state, whereas 5 malignant melanomas were receptor negative. The clinical relevance of these findings is not yet clear due to the short follow-up of the patients.

Binding Sites↗
PubMed1985

Defining scholarly activity in nursing education.

In an attempt to address the question of what activities should be considered scholarly, thereby warranting their inclusion in a nursing faculty evaluation model, a study was undertaken which surveyed all National League for Nursing accredited baccalaureate educational programs. The items in the instrument were generated utilizing the Delphi method and a pilot study established inter-respondent reliability. A response rate of 73% was attained. Scholarly activity was considered highly important in evaluation for promotion and tenure in over 50% of the schools. There were distinct differences in the activities deemed scholarly when respondents were broken down into categories such as size and type of institution and the existence or non-existence of graduate nursing programs in the same institution.

Colorado↗
PubMed1984

[Detection of papillomavirus capsid antigens and human papillomavirus 16-related DNA in Bowenoid papulosis and Bowen disease].

In one out of 22 cases of histologically diagnosed bowenoid papulosis, we could detect human papilloma virus (HPV) capsid antigen in paraffin sections fixed with formalin by means of the peroxidase-antiperoxidase (PAP) test; there were no positive findings regarding biopsies taken from Bowen's disease. Southern blot hybridization technique revealed HPV 16 DNA in 8 out of 10 cases of bowenoid papulosis; there was one positive identification out of 5 cases of Bowen's disease.

Adult↗
PubMed1984

Acanthosis nigricans maligna. Clinical and virological investigations.

2 cases of acanthosis nigricans associated with an adenocarcinoma (signet ring cell carcinoma) of the stomach and a metastasizing small-cell carcinoma of unknown origin are reported. In both cases the skin lesions preceded the diagnosis of the carcinoma by months and acanthosis nigricans maligna was suspected by onset and localization of the dermatosis. There was no evidence of a papillomavirus etiology of the warty skin lesions. Virus particles could not be demonstrated either in ultrathin sections or in buffer extracts. Virus-specific DNA was not detectable after CsCL-ethidium bromide gradient centrifugation and cellular DNA did not hybridize under stringent or relaxed conditions with 32P-labelled human papillomavirus 6 or human papillomavirus 8 DNA.

Acanthosis Nigricans↗
PubMed1983

[Roentgenmorphologic findings in scleroderma].

In 28 patients with progressive systemic sclerosis clinical symptoms are correlated with roentgen findings. The systemic disease of connective tissue shows typical roentgenological signs, such as soft tissue calcifications, generalized or localized osteoporosis, arthritis, dysfunction of oesophagus, small and large bowel, pulmonary fibrosis and cardiomegaly. A limited prognostic statement according to a clinical and radiological classification seems possible.

Adolescent↗
PubMed1983

Effect of oral aromatic retinoid (Ro 10-9359) on human papilloma virus-2-induced common warts.

Persisting human papilloma virus (HPV) 2 induced common warts of a chronic lymphatic leukemia patient were orally treated with aromatic retinoid Ro 10-9359 (Tigason). Clinically, the lesions improved rapidly. Virus-specific cytopathogenic effects (CPE), virus particles and viral DNA were no longer detectable. Therapy was discontinued because of the development of a liposarcoma, which led to a complete relapse of the cutaneous lesions. HPV-2 specific parameters, CPE and viral DNA, were restored. Comparison of the restriction enzyme cleavage patterns revealed that warts before and after therapy contained the same HPV-2 subtype. The implications of the observation on the effect of Tigason on virus-induced papillomas are discussed.

Administration, Oral↗
PubMed1983

[Morphological studies of papillomatosis confluens et reticularis in diabetes mellitus].

Macroscopically papillomatosis confluens et reticularis (PCR) is a typical dermatosis with three different clinical forms. Histologically the characteristics are orthokeratosis, papillomatosis and hyperpigmentation. A case report of PCR and diabetes mellitus reveals further histological factors, these being interstitial and intracellular edema in the epidermis and a homogenization of collagen and rarefication of elastic fibres. Ultrastructurally intracytoplasmic lipid vacuoles in the basal and suprabasal squamous cell layer were a prominent feature. These findings could be demonstrated in normal and PCR skin, which until now has not been described in the skin of diabetes mellitus patients. The question arises if PCR can be interpreted as a symptom of a fat metabolism disease in which unknown additional factors may play a role.

Adipose Tissue↗