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Biomedical subjects

B Kraus

Publications and source records attributed to B Kraus.

At least 73 records · Page 4Linked to original sources
PubMed1976

The juxtaglomerular apparatus in malignant hypertension of man.

Investigation of the behaviour of the renal juxtaglomerular apparatus in 19 patients with malignant hypertension has shown that in kidneys fixed immediately after operation the juxtaglomerular granulation index is twice as high as in autopsy kidneys. The formation of renin by the epitheloid cells begins with the appearance of osmiophilic substances in the region of the endoplasmic reticulum. The first stages of granule formation are small rhomboid particles in the Golgi cisternes, which aggregate to form bigger round or polymorphic granules in the Golgi area. In pathological conditions the substances synthesized may be set free and become active locally as a result of fibrinoid necrosis of the vascular wall. The rate of production is increased firstly by forcing the production of active agents in the preexistent epitheloid cells, secondly by transformation of the so-called bivalent cells and finally, by cell division. In accelerated hypertension the production of renin also takes place in nephrons whose glomeruli, tubules and macula densa, are damaged. There is a correlation between blood pressure elevation and the juxtaglomerular granulation index.

Adult↗
PubMed1976

Vascular reactivity to angiotensin II and to norepinephrine in diabetic subjects.

Vascular responsiveness to infused angiotensin II and to norepinephrine was determined in 14 normal subjects and two groups of diabetic subjects, 16 with no clinically detectable diabetic complications and 14 with diabetic retinopathy but no clinical evidence of nephropathy. All were maintained on a 100-mEq. -Na- 100-mEq. -K diet. Serum electrolytes, 24-hour urinary sodium, creatinine clearance, and plasma renin activity did not differ significantly among the groups. Group mean baseline diastolic pressure in those with retinopathy was higher than in normal subjects but no significantly different from that of uncomplicated diabetics. The pressor dose of angiotensin II (ng./kg./min. to increase diastolic blood pressure 20 mm. Hg) for each group respectively was 11.5 +/-0.9, 12.9+/- 1.3, and 8.3 +/- 1.3, and the slope of the dose-response curve (mm. Hg rise in blood pressure resulting from the infusion of 1 ng./kg./min. following the initial increment in blood pressure) was 2.0 +/-0.2, 1.6+/-0.2, 3.3+/- 0.6. For norepinephrine, the pressor doses were 163 +/- 24, 212+/-21, and123 +/- 11 and slopes were 0.17 +/- 0.03, 0.13 +/- 0.02, and 0.20 +/-0.02. Neither diabetic group differed significantly from normal subjects. Diabetics with retinopathy were more sensitive to angiotensin II, pressor dose (P less than 0.059) and slope (P less than 0.02), and to norepinephrine, pressor dose (P less than 0.006) and slope (P =0.05) than those without complications. These data suggest that vascular reactivity is enhanced in diabetics with retinopathy.

Angiotensin II↗
PubMed1975

[Mitochondrial changes in the tubular epithelium of wistar-rats with spontaneous nephropathy (author's transl)].

The proximal tubular epithelium of Wistar-rats with a spontaneous glomerulopathy is greatly strained by the consecutive massive tubular storage of proteins in aging animals and by the progression of the disease. Together with the onset of increased tubular insufficiency the mitochondria show remarkable changes. These changes occur mainly in the epithelial cells containing many pigmented residual bodies. Besides changes of the mitochondrial arrangement of the cytoplasm most frequently megamitochondria can be seen. Matrix and cristae may contain multiple inclusions, the nature of which is not clear. The changes in the mitochondria are regarded as the expression of adaptation to an altered situation of energy.

Age Factors↗
PubMed1975

[The lymphocytoma of the lung. Etiology, pathogenesis, differential-diagnosis and dignity (author's transl)].

Tumor-like lymphoplasias of the human lung are named in different ways and differently classified according to their characteristic features: inflammatory, benign, semi-malignant, and malignant. From the cellular point of view the term "lymphocytoma" is appropriate. There are different stages in the course, each respresenting characteristic histological pictures. An early symptom is a strong lymphatic hyperplasia in the walls of small bronchia followed by a voluminous lymphoplasmacellular infiltration of the interalveolar septa with formation of follicles containing germinal centres. The interstitial infiltration may periodically become more "colored" by facultative participation of basophil stem cells, macrophages, reticular cells, eosinophiles and multinucleated giant cells. The alveolar epithelium reacts with hypertrophy and hyperplasy and finally the alveoles are totally obliterated. Fibroses and hyalinoses develop in later stages. Clinically and morphologically they bear a close relationship to the inflammatory lymphoma Saltzstein and to the lymphoid interstitial pneumonia Liebow. Probably there are transitorial stages between these diseases. The cause is to be seen in immunological reactions of the lymphoepithelial system of the lung. Antigens contact immunocompetent cells at the tonsilla pulmonis. Thus the lymphoplasia is put into action. Is the noxa not diminished it may be followed by the formation of autoantibodies, which support the chronic course. The process can become independent and in that way assume the character of a tumor. Such cases may be named immunocytoma.

Adult↗
PubMed1975

[Serum and liver lipase activity in chickens during the 1st month of life].

Method according to DIRSTINE (1968) was employed to study the activities of serum and liver lipase in White Leghorn cockerels during early post-incubation ontogenesis; as to serum lipase, two embryo intervals were also studied (the 13th and 20th day of incubation). From the average value of 4.4 ummol (13th day), serum lipase activity increased to the average value of 7.5 ummol (20th day). The first day after hatching the average value was 3.5 ummol which remained almost unchanged until the 9th day, with the exception of a slight drop the third day; an increase of activities was observed on the 13th day (4.9 ummol), 15th day (3.5 ummol), 21st day (7.6 ummol), 22nd day (5.5 ummol), and 24th day (8.8 ummol). The minimum average activity of 2.5 ummol was measured the 32nd day. Liver lipase activity was observed to drop from the first-day starting value of 20.6 ummol to 9.8 ummol (the second day), with a subsequent increase to 14.9 ummol (the 4th day). The maximum values were recorded the 13th day (26.2 ummol) and the 15th day (28.7 ummol) whereas the minimum average value was obtained the 32nd day (6.3 ummol). Liver lipase activity drop on the second day of age and serum lipase activity drop on the third day with subsequent increase are probably associated with the change from yolk-sac nutrition to feeding per os. Some stabilization of serum and liver lipase occurs the 32nd day; the values found in adult fowl were almost the same as the 32nd day values.

Adrenocorticotropic Hormone↗