Biomedical subjects
Publications and source records attributed to W Schmidt.
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We report on 12 early prenatal diagnoses of "Potter syndrome" and other severe fetal kidney diseases by ultrasonic observations of persistent oligohydramnios and absence of kidney function; seven pregnancies were terminated. These cases are discussed together with others observed in a total of 23 families. Special attention is given to the difficulty of classifying the various kidney diseases pathoanatomically, and also of determining the recurrence risk in the affected families. For genetic counselling, the possibility of early prenatal diagnosis is a practical solution to this problem. Routine ultrasound supervision of pregnancies can already detect a first, sporadic case of the various kidney diseases.
The properties of the catecholamine-storing organelles from transplantable rat phaeochromocytoma and rat adrenal glands were compared by density gradient centrifugation. It was shown that tumour granules are more heterogeneous and less dense than adrenal granules. Both granule preparations can take up catecholamines and nucleotides by a process driven by an electrochemical proton gradient. Dopamine beta-hydroxylase and glycoprotein III were analysed by immunological techniques. Glycoprotein III was shown to be a specific component of chromaffin granules. Tumour tissue (average weight 700 mg) contains amounts of these antigens comparable to those in 210 adrenals. The biosynthesis of granules in the tumour apparently occurs at a low rate, making turnover studies difficult. The transplantable rat phaeochromocytoma is very useful for studies on the uptake properties and the immunological characteristics of rat catecholamine storage granules because on tumour provides an amount of material that could otherwise be obtained only from a large number of adrenal glands.
The significance of ultrasound examinations in early stages of pregnancy is illustrated by the detection of four severe congenital malformations within the first trimester and one malformation syndrome within the first part of the second trimester of pregnancy. We report on the diagnosis of a fetal POTTER syndrome (13 weeks), an anencephalic fetus (13 weeks), MECKEL-GRUBER syndrome (16 weeks), fetal exomphalos (12 weeks) and finally "Siamese twins" (11 weeks). Characteristic ultrasonographic findings are presented and described in detail. The incidence of these severe fetal abnormalities vary between 1:1000 (anencephaly), 1:6000 (exomphalos), 3:10,000 (POTTER-Syndrome), 1:50,000 (MECKEL-GRUBER Syndrome) and 1:250,000 (conjoined twins) live births. The sonographical diagnosis of all these malformation syndromes could be established by thorough and repeated inspection of the fetal head and fetal body with longitudinal and transversal scans. It is concluded, that the high and still increasing reliability congenital structural anomalies renders routine systemic ultrasound screening an attractive possibility already at this "early" stage of pregnancy.
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Adrenal chromaffin granules are known to possess an F1-ATPase which according to biochemical criteria is very similar to the mitochondrial one. To find a morphological equivalent for this enzyme chromaffin granules from bovine adrenal medullar were subjected to negative staining and freeze-etching. With both methods globular particles of 8 to 9 min diameter could be demonstrated on the surface of these organelles. A single granule possessed on average 22 particles. In negative staining the particles appeared separated from the membrane by a stalk of 8 nm. This typical morphological appearance was independent from a great variety of experimental procedures. After freeze-etching the particles were closely apposed to the membrane without any evidence for an interposed stalk. Pretreatment of chromaffin granules with pronase or trypsin led to a time dependent disappearance of the surface particles. In negative staining the stalked of chromaffin granules were found to be very similar in structure and size to those of mitochondria which have already been identified as F1-complexes. Based on this observation and other lines of evidence we suggest that the stalk particles found on the surface of chromaffin granules represent the F1-complex of the proton-pumping ATPase of these organelles.
We investigated the effect of whole body irradiation (6.0 Gy) on the development of low-dose streptozotocin diabetes in male C57 Bl/KsJ-mice. After induction of the process of diabetes development irradiation failed to interfere with the development of hyperglycemia and did not modify the reduced pancreatic insulin content after exogenous diabetes induction.
A prospective double-blind clinical trial was carried out to determine whether ambroxol (bromhexine metabolite VIII) treatment (1000 mg/day for a period of 5 days) reduces the risk of hyaline membrane disease (HMD) in potentially premature infants. Amniocentesis was performed before the first and 24 h after the last application of ambroxol or placebo to assess the development of the total phospholipid phosphorus content, the L/S ratio, the P/S ratio, and the properties of the surface tension of the amniotic fluid after ambroxol or placebo. There were 246 infants born to 224 mothers. Of the 116 infants with less than or equal to 36 completed weeks' gestation, 56 were in the ambroxol and 60 in the placebo group. No differences between groups occurred in risk factors for HMD (diabetes, asphyxia, male sex, cesarean section). Statistically significant differences in favor of the infants in the ambroxol group were found in the HMD incidence: 23.2% in the ambroxol group compared with 41.7% in the placebo group (p less than 0.05). There was no reduction of the HMD incidence in the less than or equal to 32-week gestational age category in the ambroxol group compared with the placebo group inspite of the fact that all the examined parameters for determining lung maturity reflected a stimulatory effect of ambroxol compared with the results of the placebo group, particularly before the 33rd week of gestation. Prolonged rupture of the membranes played no protective role against HMD.
A verbal description of a mathematical model is given which theoretically explains the basis of the biological specificity of the tumour-tetanus phenomenon. The main postulate of the model concerns a mitosis-controlled clostridial growth. It is based on the experimental and mathematical demonstration that clostridia are stimulated by the dividing tumour cells. In particular, we have shown that the parameters which describe the kinetics of the pacemaker cells of the host can be deduced from the experimental tetanus lethality curves of the animals. Using these mathematical parameters one obtains stimulated curves which excellently fit the experimental test results. The pacemaker mechanism is the prerequisite of a specific clostridium-tumour assay utilizing serological methods with atoxic non-oncolytic clostridial strains as test microbes.
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Lipid droplets, between 0.5 and 1.0 microns in size, were recorded by means of optical light microscopy from syncytiotrophoblast, villous stroma, and villous vessels in the full-term human placenta. Their distribution patterns varied greatly in different sections of the villous tree. -- Lipid droplets were recorded also from a thick smear in arterial and venous umbilical cord blood, following haemolysis and concentration of haemolysate. They resembled chylomicrons. -- Histochemical assays have shown the droplets to consist of triglycerides and a cover of phospholipids, quite often visible, sometimes even of a mixture of triglycerides and phospholipids. Some of the droplets, which were located in the villous stroma, seemed to consist of phospholipids only. -- The conclusion drawn from morphological findings is that triglycerides in the form of chylomicrons are absorbed through endocytosis from maternal blood, before they traverse the syncytium to penetrate the embryonic vascular system. Phospholipids are thought to be admixed in that phase. Some of the phospholipid droplets are actually formed in the syncytium.
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Reviewing the records of 131 patients with malign tumors of the mouth and oropharynx 36 (35%) alcoholics were found among 103 male patients with carcinoma. The highest incidence of alcoholism (58%) was seen in patients with carcinoma of the floor of the mouth. In alcoholics the age distribution showed a peak in the 4th decennium, whereas non-alcoholics had this peak in the 6th decennium. With 64% T3-tumors the alcoholics revealed on an average markedly more advanced tumor stages before treatment than the other patient group with only 29% T3-tumors; metastases in the regional lymphnodes were seen in 50% of the latter, but in 72% of the alcoholics. Skin reaction to radiation therapy appeared particulary pronounced more often in alcoholics (87%) than in the other patients (63%). The 3-year survival rates were 38.5% (alcoholics) and 44.5% (non-alcoholics). These observations suggest that alcoholism with its numerous accompaniments does not only play a role in etiology, but does also have unfavourable effects on the course and the prognosis of cancer of the mouth and oropharynx.
In the course of a series of histiophysiological tests, a structural analysis was made of the different layers of foetal membranes. They were based on optical light and electron microscopy. Particular attention was given to the question for the secretory and resorptive faculties of this intermediate layer between the compartments of mother and amniotic fluid. --The first tests were made by means of amnion morphology, histochemistry, and thin-layer chromatography for the purpose of elucidating the composition of lipid droplets. Their form and chemical composition were both found to be similar to those of lipid droplets (liposomes) which were suspended in amniotic fluid. This fact, together with the morphological aspect, was likely to indicate hat the liposomes were expelled by exocytosis from amniotic epithelial cells. The endoplasmatic reticulum was active and granular, an indicator to sizeable formation of proteins in the amniotic epithelial cells. --Analysis by thin-layers chromatography showed lipids in both the amnion and amniotic fluid to consist of lysolecithin, sphingomyelin, phosphatidylserin, phosphatidylinosite, lecithin, kephalin, phosphatidyl-ethanolamine, cholesterinester, triglycerides, and sebacic acids. --The large intercellular spaces in the amniotic epithelium were found to form a labyrinth between surface differentiations of surrounding cell walls. There were numerous vesicles in the amniotic epithelial cells which were attributed to absorption of amniotic fluid from intercellular spaces as well as to its emission to cell surfaces. Some of the amniotic fluid was removed through the connective tissue of the amnion. Fibroblasts, located in connective tissue of the amnion, differed from connective tissue cells of adults, in that they were highly capable of synthesizing and storing both lipids and glycogen. They were also capable of meconium storage. Structures recorded by electron microscopy from the intermediate layer were safely identified as remnants of extraembryonic mesenchyma.
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Results obtained from studies into chorion (consisting of chorionic connective tissue and trophoblast) and into decidua are reported in Part II of this publication.--Storage of glycogen and lipids in high quantity was recordable from the cells of these three layers. Lipid droplets did not substantially differ for composition from storage phenomena described elsewhere in the context of amnion.--The trophoblast consisted of cells which exhibited signs of unusual storage form. There was enormous vacuolisation of cytoplasm. This as well as manifestations of nuclear polymorphism were interpreted as expressions of excessive cellular activity rather than of degenerative change. Spaces between trophoblast cells were filled up with a substance of structural and histochemical similarity with basal lamina, but not identical with the latter. The label of chorionic "epithelium" appears to be no longer justifiable for the presence of intercellular substances.--The connection between maternal (decidual) and infantile (chorionic) tissue was maintained in the fetomaternal contact zone. Here, perished cells and their products were transformed into structureless material, with small trophoblast cells being incorporated.--A network of extremely large blood capillaries was found to be incorporated into the decidua.--The cells in each of the above layers were obviously linked together in functional groups. The buildup of lipids and glycogen was attributed to phylogenesis and early embryogenesis.