The kinetics of phagocytosis of colloidal substances in experimental insulinopenic diabetes.

Because of a reduction in the rate of phagocytosis by the reticuloendothelial system, the removal of large doses of colloids from the blood is much slower in rats with experimentally induced insulinopenic diabetes than in controls having a normal metabolism. This kinetics corresponds to the exponential response reported in the literature for an injected dose exceeding the "critical dose", with phagocytosis being a crucial parameter. In the case of smaller doses of colloids, however, clearance follows a different kinetic pattern which is here formulated mathematically.

The permeability of large arteries to labeled protein.

Using labeled albumin, the permeability index was determined for the aorta and other arteries of the rabbit after different circulation times. The results were reproducible. Different indices of permeability were obtained for different arteries.

[Antigenicity of the glomerular basement membrane of longtime diabetics].

8 rabbits were immunized with isolated fractions of renal glomerular basement membrane of 18 human diabetics and 18 human controls. The antisera were tested with the indirect immunofluorescence at frozen kidney sections of 31 longtime diabetics and 31 controls. One part of the sera was absorbed with isolated glomerular basement membrane of both groups before.

Glomerular immune complex deposition, circulating immune complexes, and antibodies in experimental insulinopenic diabetes.

Compared with control animals with a normal metabolism, rats with insulinopenic diabetes generally show an increase in glomerular deposition of complement-fixing immune complexes after immunization with bovine albumin and bovine gamma-globulin. Compared with the control group, the serum of the diabetic animals showed a reduction in the titers of IgM-isotype antibodies, which have a lower affinity. The concentration of the circulating immune complexes is the same.

[Changed retinal cell content in diabetics (author's transl)].

A quantitative exploration of retinal cell content was carried out in diabetics and metabolically healthy controls of the same age and sex distribution. After diabetes of 6 years duration there was a drastic diminution of cells in the ganglion cell layer of the central retinal area, while the number of cells of the inner nuclear layer was slightly reduced and that of the outer nuclear layer was still unchanged. The periphery of short duration diabetic retinae showed a normal cell content in all nuclear layers.

[Frequency of metastases of extracranial tumours in the choroid plexus (author's transl)].

5% of malignant extracranial tumours metastasize into the choroid plexus, especially tumours with a higher grade of malignancy. Metastases in the choroid plexus are more frequent than mestastases in the brain corresponding to the relation of weight of choroid plexus and brain. This fact can be explained with the vascularisation by capillaries containing endothelial pores.

Phagocytosis of inert particles in the reticuloendothelial system in rats with experimental insulinopenic diabetes.

Phagocytosis of inert, radioactive gold particles in the reticuloendothelial system in rats in the case of experimental insulinopenic diabetes was studied. In the spleen, phagocytosis was seen to have fallen to a relatively low level after four weeks from the induction of diabetes. In the liver, there was noted a reduction of phagocytosis per gram of organ, though it remained the same for the total organ which in the case of diabetes mellitus increases in weight relative to body weight.

[Permeability of the arterial vessel wall for labeled plasma proteins].

The permeability of the large arteries may be analysed by different methods. It is of different size in the individual arteries and is increased by hypoxia, by hypertension and by mediators. Thus increasedly atherogenic substances may enter the wall of the vessel.

[Comparison of the results of computer tomography and isotope diagnostics in pathologic processes of the infratentorial range (author's transl)].

1. Computer tomography is much more clearly superior to cranial scintigraphy with regard to the identification and localization of pathologic infratentorial processes, than in the supratentorial range. 2.

Index of permeability of large arteries to labeled albumin after administration of prostaglandin E2.

Prostaglandin (PG)E2 tends to increase the permeability to labeled albumin of the arterial walls of rabbits. The blood pressure decreases after administration of PGE2. The increase in permeability is probably due to direct effects of prostaglandin upon the endothelium, perhaps to an increase of cytopempsis or formation of leaks in the integrity of the cell layer.

[Cysts in the villous stroma of the placenta in maternal diabetes mellitus (author's transl)].

Edemateous placentae of diabetic mothers have been examined by light as well as electron microscopy. In addition to typical fetal capillaries there were observed thin-walled cysts containing Hofbauer-cells rather than blood cells which, unlike the capillary system, cannot be filled up with intraarterially injected ink. Derivation and significance of these cavities are discussed.

Arterial permeability to labeled protein.

Labeled albumin, which was administered intravenously, was detected, with the use of a scintillation counter, in the aortic wall of rabbits. Relative to weight, the permeability index was highest in the aortic arch and abdominal aorta and lowest in the medial thoracic aorta. Angiotensin II and various mediators were found to increase the permeability of the aortic wall.

The problem of diabetic angiolopathy in sand rats (Psammomys obesus).

No diabetic angiolopathy was found in the retinas, kidneys and skeletal muscles of protodiabetic and overtly diabetic sand rats. The terminal blood vessels were investigated using histological, enzyme histochemical, immunofluorescence microscopic, autoradiographic and electron microscopic methods. There seems to be little or no connection in sand rats between the diabetic metabolism syndrome and the metabolic process leading to angiolopathy.

Scanning electron microscopy of the aorta.

The folds of the intimal surface do not represent the endothelia. Rather, they are produced by tissue shrinkage occurring during preparation, with the shrinking process proceeding in the arteriosclerotic bed differing from that in the normal vessel wall. Consequently, the surface appearance, or texture, of arteriosclerotic beds is different from that of the normal vessel wall.

Renal biopsies performed on diabetics.

Metabolic disorders and immunological factors are discussed in connection with the pathogenesis of diabetic microangiopathy. Renal biopsies were obtained from 22 diabetics (8 women aged 18 to 53, 14 men aged 15 to 52). 7 of the 22 patients had been suffering from diabetes for 2 weeks to 3 years, 10 for 7 to 25 years, 2 showed a pathological glucose-tolerance test, i.

The epithelial and capillary basal laminae of the placenta in maternal diabetes mellitus.

The thickness of the epithelial and endothelial basal laminae was determined in placentas from mothers without known metabolic disease (control) and mothers with diabetes mellitus. The measurements were carried out on electron micrographs. Frequency distributions and statistical parameters were calculated; in 20 cases, 16,331 values were measured.