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Kidney biopsies from 10 patients with diagnosed insulin-dependent diabetes mellitus of various duration with clinical manifestations of hyperglycemia, increased rate of glomerular filtration, presence or absence of microalbuminuria, were studied morphologically. Gradual increase of kidney alterations was observed: changes of thickness and loosening of basal membrane of glomerular capillaries, its focal homogenization, partial mesangium increase due to the increase of membranous substance and decrease of cellular component. These alterations positively correlate with immunohistochemistry of renal glomeruli. Dynamics of morphological changes does not show a direct connection with the patient age and the duration of diagnosed disease but is stipulated by the presence of one or another antigen of the class II major histocompatibility complex.

Kidneys of 16 Wistar rats were examined by light and electron microscopy, immunofluorescence and biochemically for the transamidinase activity at various periods of experimental diabetes induced by the fractionated intraperitoneal administration of low (40 mg/kg) doses of streptozotocin. 18 rats of the same age and sex served as control. This model of diabetes is characterized by a gradual decrease of the serum immunoreactive insulin, increase of hyperglycemia, the presence of "insulitis" 19 days after the beginning of the experiment and the development of nephropathy in the genesis of which immune mechanisms might participate. Transamidinase activity correlated with the alterations of renal tubuli. The conclusion is made on the possibility of using this model of experimental diabetes for studying the pathogenetic mechanisms of renal lesions in diabetes; transamidinase activity allows one to evaluate the nephron function in diabetic nephropathy.

Ten patients with insulin-dependent diabetes mellitus not associated with any signs of diabetic nephropathy were examined for the reserves of filtration renal function and early morphological alterations in organ tissues. The reserves of filtration were detected under the conditions of acute oral administration of protein (1.5 g/kg) as difference between the initial and stimulated levels of glomerular filtration (GF). Two groups of patients were distinguished: group I included patients with preserved filtration reserves (increment of GF amounted to 35%), group II included patients with no filtration reserves (reduction of GF was 20%). Both the groups differed significantly only in the initial level of GF (120 and 209 ml/min, respectively) and in the degree of morphological changes in the glomeruli: group I manifested minimum structural changes, group II showed the commencing diabetic glomerulosclerosis characterized by pronounced injury to the manubrium of the glomeruli. Therefore, the lack of filtration reserves in diabetes mellitus patients suggests the presence of the commencing diabetic glomerulonephritis even with the lack of the clinical signs of renal injury, which does not require the resorting to organ biopsy. The primary injury to the manubrium of the glomeruli is likely to be related to a high gradient of intraglomerular hydrostatic pressure, resulting in hyperfiltration.

A description is given of the design and characteristics of an electron-beam-controlled CO2 laser with an output energy of up to 30 J and a pulse repetition frequency of up to 50 Hz. In the self-contained regime the input and output energies per pulse fell rapidly as the number of pulses increased and then rose and became stabilized at 50–60% of the initial level after 104 pulses. The rise in these parameters was associated with a change in the content of CO, O2, and the oxides of nitrogen in the active mixture during operation. It was found that stratification of the discharge and its operation in regions of increased electric field resulted in the existence of a prolonged low-current discharge during its final stage of development.

Model systems, comprising frozen glassy solutions of stabilized radicals and biradicals of the nitroxyl type, have been used to test the applicability of electron-electron double resonance in electron spin echo (ELDOR ESE) in studies of the spatial distributions of free radicals arranged in groups in solids. The method was used to investigate the spatial distribution of alkyl radicals generated by the sensitized photolysis of glassy naphthalene solutions in decalin at 77 K. and detected radical pairs.

1. The optimum conditions for conducting coupling reactions of terminal acetylenes with organic halides in the presence of amines, CuI, and palladium complexes were determined. 2. Pd(0)-Pd(PPh3)2 and Pd (II)-R'PdX (PPh3)2 complexes are intermediates in the catalytic reactions of RC≡CH with R'X(“Pd,” Et3N, CuI).

1. Terminal acetylenes have been reacted with allyl halides under mild conditions to give quantitative yields of the coupling products. 2. The best base for these reactions is K2CO3 and the most active catalyst is CuI. 3. Under these conditions, the reaction is not accompanied by allyl rearrangement of 1,1-disubstituted prop-1-ene 3-halides.

Vertebrate gastrulation involves complex coordinated movements of cells and cell layers to establish the axial structures and the general body plan. Adhesion molecules and the components of extracellular matrix were shown to be involved in this process. However, other participating molecules and detailed mechanisms of the control of gastrulation movements remain largely unknown. Here, we describe a novel Xenopus gene camello (Xcml) which is expressed in the suprablastoporal zone of gastrulating embryos. Injection of Xcml RNA into dorsovegetal blastomeres retards or inhibits gastrulation movements. Database searches revealed a family of mammalian mRNAs encoding polypeptides highly similar to Xcml protein. Characteristic features of the camello family include the presence of the central hydrophobic domain and the N-acetyltransferase consensus motifs in the C-terminal part, as well as functional similarity to Xcml revealed by overexpression studies in Xenopus embryos. Xcml expression results in the decrease of cell adhesion as demonstrated by the microscopic analysis and the blastomere aggregation assay. Cell fractionation and confocal microscopy data suggest that Xcml protein is localized in the secretory pathway. We propose that Xcml may fine tune the gastrulation movements by modifying the cell surface and possibly extracellular matrix proteins passing through the secretory pathway.

It was shown that in reactions of aryl iodides with terminal acetylenes catalyzed by palladium complexes, potash or alkali can be used as a base in the interfacial system.

This article examines the high-temperature reaction between boron carbide and silicon and confirms the assumption that silicon carbide and silicon hexaboride are the reaction products by calculating the isobaric-isothermal potential of the reaction at temperatures above the melting point of silicon and as high as the temperature of decomposition of silicon hexaboride. X-ray diffraction and crystallographic results are presented for the solution and crystallization behavior of the reaction participants.

Heterogeneity of diabetes mellitus, as the specialists see it nowadays, is determined by the presence of histocompatibility antigens and the onset of immune autoaggression against beta-cells of islet of Langerhans which leads to formation of circulating immune complexes and complexes in situ. This may give rise to diabetic nephropathy. In florid diabetes mellitus there also appeared disturbances induced by metabolic derangement, relevant antigens being then exogenic insulin and low-molecular lipoproteins entailing drastic changes of the basal membrane of glomerular capillaries, plasma saturation of the vascular walls and eventual hyalinosis and capillary obliteration.

1. Terminal acetylenes have been reacted with allyl halides under mild conditions to give quantitative yields of the coupling products. 2. The best base for these reactions is K2CO3 and the most active catalyst is CuI. 3. Under these conditions, the reaction is not accompanied by allyl rearrangement of 1,1-disubstituted prop-1-ene 3-halides.