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Biomedical subjects

M Heinrichs

Publications and source records attributed to M Heinrichs.

29 records · Page 2Linked to original sources
PubMed1986

Ontogenetical development of the chick and duck subcommissural organ. An immunocytochemical study.

The ontogenetical development of the subcommissural organ (SCO) was investigated in chick embryos collected daily from the 1st to the 21st day in incubation. Some duck embryos, and adult chickens and ducks were also studied. Immunocytochemistry using an anti-Reissner's fiber (RF) serum as the primary antibody was the principal method used. In the chick embryos the events occurring at different days of incubation were: day 3 morphologically undifferentiated cells in the dorsal diencephalon displayed immunoreactive material (IRM); days 4 to 6 immunoreactive cells proliferated, formed a multilayered structure and developed processes which traversed the growing posterior commissure and ended at the brain surface; day 7 blood vessels penetrated the SCO, scarce hypendymal cells appeared, the first signs of ventricular release of IRM were noticed, appearance of IRM bound to cells of the floor of the Sylvius aqueduct; day 7 to 10 the number of apical granules and amount of extracellular IRM increased progressively; day 11 RF was observed along the Sylvian aqueduct, day 12 RF was present in the lumbar spinal cord; day 13 IRM on the aqueductal floor disappeared; days 10 to 21 hypendymal cells proliferated, developed processes and migrated dorsally, ependymal processes elongated and their endings covered the external limiting membrane. In adult specimens the ependymal cells lacked basal processes and the external membrane was contacted by hypendymal cells. the duck SCO appears to follow a similar pattern of development.

Aging↗
PubMed1982

Immunoreactive neuropeptide systems in avian embryos (domestic mallard, domestic fowl, Japanese quail).

In embryos of the domestic mallard, domestic fowl, and Japanese quail vasotocin-, mesotocin-, luliberin (LHRH)-, met-enkephalin-, corticotropin-, and somatostatin-immunoreactive perikarya and fiber formations were visualized at different incubation stages by means of the PAP technique (Sternberger 1979). The most striking results were: (1) Vasotocin-, mesotocin-, and luliberin-immunoreactive systems display, up to the late embryonic period, morphological features most probably related to a neurohormonal function. (2) Met-enkephalin immunoreactivity appears very late during embryonic life; it is restricted to fiber networks and not found in perikarya. (3) Corticotropin immunoreactivity is observed in the tuberal region temporarily at the end of the second and the beginning of the last third of the incubation period. (4) Somatostatin-immunoreactive material is present (i) at the end of the first third of incubation, in association with the olfactory system; (ii) during the same period, adjacent to thin-layered portions of the roof of the brain; (iii) shortly thereafter, in cells of both pancreatic primordia and thyroid gland; and (iv) onward from the middle of the incubation period, in a mesencephalic cell group. The striking difference, in the early embryo, between the mature somatostatin plays a role in the development of the brain, as well as the pancreas, and the thyroid gland.

Adrenocorticotropic Hormone↗
PubMed1976

[Musical-rhythmic discrimination ability and recall in children with reading and spelling disorders].

Thirty 9- to 11-year-old children of normal intelligence, who are poor readers and spellers, were tested using shortened series of problems of the Seashore test of musical talents as well as Colured Progressive Matrices. Also, the children had to write from dictation using Kossakowski's table of words. All of the problems, with the exception of writing from dictation, were also presented to, and solved by, a correspondingly composed reference group of thirty normal schoolchildren. There were found considerable statistically significant group differences especially in respect of the ability to absorb successions of tones and distinguish between different tone colors and intensities of sound. The importance of these results to the development of methods of early diagnosis is discussed in detail.

Auditory Perception↗
PubMedDate not supplied

Psychoneuroendocrinological contributions to the etiology of depression, posttraumatic stress disorder, and stress-related bodily disorders: the role of the hypothalamus-pituitary-adrenal axis.

Following the assumption that stressors play an important part in the etiology and maintenance of psychiatric disorders, it is necessary to evaluate parameters reflecting stress-related physiological reactions. Results from these examinations may help to deepen the insight into the etiology of psychiatric disorders and to elucidate diagnostic uncertainties. One of the best-known stress-related endocrine reactions is the hormonal release of the hypothalamic-pituitary-adrenal (HPA) axis. Dysregulations of this axis are associated with several psychiatric disorders. Profound hyperactivity of the HPA-axis has been found in melancholic depression, alcoholism, and eating disorders. In contrast, posttraumatic stress disorder, stress-related bodily disorders like idiopathic pain syndromes, and chronic fatigue syndrome seem to be associated with diminished HPA activity (lowered activity of the adrenal gland). Hypotheses referring to (a) the psychophysiological meaning and (b) the development of these alterations are discussed.

Arousal↗
PubMedDate not supplied

Pathology of the oropharyngeal cavity in six strains of rats: predisposition of Fischer 344 rats for inflammatory and degenerative changes.

The sagittolongitudinal histopathological evaluation of the oropharyngeal cavity in 6 strains of rats revealed a clear predisposition of the Fischer 344 strain for degenerative and inflammatory lesions in this region. A degeneration and calcification predominantly of the laryngeal cartilage is evident in 72%, granulomas of the seromucinous glands in 38%, and an inflammation with bacterial colonies or plant material in the basal part of the laryngotracheal junction in 26% of the Fischer 344 rats. The incidences of these types of lesions were negligible in the other rat strains evaluated. The comparison of control Fischer 344 rats from 2 carcinogenicity studies (untreated group; gavaged group with water, pH 10; gavaged group with propylene glycol/methocel) showed an influence of the gavage technique with the solvent on the survival rate in the female Fischer 344 rats. The lower survival rate was accompanied by the occurrence of food impaction in the oropharyngeal cavity. This increased mortality in female Fischer 344 rats was also associated with a degeneration of the laryngeal cartilages, whereas the formation of granulomas and inflammation seemed to have no direct relationship to the mortality. The gavage technique with the applied solvent was an enhancing factor in the female Fischer 344 rats on mortality, on cartilage degeneration, but not on inflammatory changes. In contrast to the females, male Fischer 344 rats had a higher incidence of granulomas and inflammation, which, however, did not influence the survival rate. In conclusion, Fischer 344 rats, especially the female sex, exposed to chronic daily irritation by gavage, are predisposed to have a high mortality rate in chronic toxicologic tests. An explanation lies in the disposition of the Fischer 344 rat to a high incidence of cartilage degeneration, which presumably leads to a dysfunction of the larynx.

Animals↗
PubMedDate not supplied

[Heart involvement in progressive systemic sclerosis (generalized scleroderma)].

17 patients with progressive systemic sclerosis were examined for cardiac involvement using standard ECG, chest X-ray, 24-h Holter ECG, and echocardiography. The control groups consisted of 7 patients with mixed connective tissue disease, 10 patients with systemic lupus erythematosus, and 10 patients with rheumatoid arthritis. The results disclosed a cardiac involvement of 70% using all 4 methods, which is more than is reported in the literature. The data also show that all 4 methods are necessary to diagnose the cardiac involvement. Conduction and rhythm disorders especially are more frequent than in other collagen vascular diseases. The use of calcium channel blockers is discussed as a new therapeutic possibility.

Electrocardiography↗