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Intraperitoneal injection of hydrocortisone in single daily doses from 0.1 to 25.0 mg/kg, for 3 days was followed by reduced activity of liver microsomal monooxygenases and decreased content of cytochrome P-450 and b5. Hydrocortisone diminished the activity of the liver cytochrome P-450 system in vivo that significantly potentiated hexenal sleep. The hydrocortisone-inhibited activity of the liver chromosome P-450 system was followed by intensified food anaphylaxis in guinea-pigs.

The authors review the theory of the development of meat products with the use of non-traditional protein sources. The main task that arises in the course of the development of combined meat products lies in the design of protein compositions whose biological value would not be inferior to that common to proteins contained by meat or to that common to an ideal protein. The authors discuss 2 varieties of combined meat products. Provide examples of calculating the amino acid content in these products. The first variety based on the replacement principle consists in the utilization of amino acid reserves in meat proteins, thereby enabling the introduction into meat products of certain amounts of less valuable proteins. The second variety is based on the design of preliminarily developed protein compositions in which the amino acid content is balanced at the expense of mutual protein enrichment.

Thirty-six patients operated on for peptic ulcer or pyloric stenosis received protein or low-lactose enpit via a probe in the early postoperative period. Twenty-four patients responded well to the intraintestinal nutrition, 6 patients satisfactorily, while the remaining 6 manifested dyspeptic disorders because of dynamic intestinal obstruction. In the control group (given beef-extract broth or decoction of dried apricots), 2 of the 13 subjects had phenomena of intestinal paresis. The nitrogenous balance in the patients given enpits was close to the state of equilibrium, whereas in the controls it was markedly negative. Enpit was found to be assimilable up to 92-95%. The authors discuss the importance of the level of protein and energy supply for reparative processes in the early postoperative period, the quality of the protein and specificity of caseins.

The single-strand specific nuclease S1 from Aspergillus oryzae (EC 3.1.4.21) was purified 600-fold in 16% yield from dried mycelia. Determination of the isoelectric point of S1 nuclease as 4.3-4.4 allowed adjustment of chromatographic conditions such that the enzyme was isolated free of contaminating ribonucleases T1 and T2. S1 nuclease so purified was used for removal of single-stranded portions from the RNA of the Escherichia coli phage MS2, which has a helical content of about 65% in vitro. At 23 degrees, increasing amounts of enzyme converted the RNA to mononucleotides in about equimolar base ratios. No small intermediates of chain length 2-8 were found. At 0 degrees, MS2 RNA hydrolysis was slower and reached, in exhaustive digests, a plateau where 70% of the substrate RNA remained insoluble in 66% EtOH. With [32P]MS2 RNA, strip chart counting of 6% acrylamide-6 M urea electrophoresis patterns of such digests gave recoveries of 80-91% in the form of defined oligomer bands. On 2.5% acrylamide-0.5% agarose gels, the molecular weights of the major oligomers were found to range from 25,000 to 41,000. Similar to purified tRNAArg used as a control, these oligomers were not resistant to pancreatic RNase-RNase T1 hydrolysis at 37 degrees, and were not bound on hydroxylapatite at 50 degrees in 0.14 M sodium phosphate (pH 6.8). Melting of the oligomers gave complex profiles without a clear Tm and showed an increase in A260 of 35% at 93 degrees over that at 28 degrees. Upon formaldehyde denaturation of MS2 RNA prior to S1 nuclease hydrolysis, no resistant oligomers were found.

The authors describe the results of studies into the common and local humoral immunological system in 60 children under one year of age suffering from atopic dermatitis of varying severity. The passive hemagglutination test with the use of a kit of erythrocytic diagnosticums devised at the Institute of Nutrition, Academy of Medical Sciences of the USSR, was used to study the degree of the child's body sensitization with cow's milk antigens and the content of IgG, IgM and IgA in the blood and that of secretory IgA in coprofiltrates. Polyvalent sensitization of the body with food antigens was found in 50% of the children examined to reveal an interplay between the degree of sensitization with the severity of the pathological process. It was demonstrated that penetration of food antigens through the epithelial barrier of the gastrointestinal tract was not related to the deficiency of the secretory IgA, since this class of immune proteins was detectable in the coprofiltrates from all the children. Besides, the content of these proteins was not reduced during the severe form of the disease. In this case, the intestine of all the children examined showed dysbacteriosis which needed correction. The blood serum manifested a decrease in the level of IgM and IgG which was more pronounced in the patients with a severe disease course.

Adult male Wistar rats received intragastrically a protein mixture containing 3H-labeled reserve protein of soy beans (PSB), the soy protein isolate 500-E of Ralston Purina Co (USA) being chosen as a protein source. Immunoreactive and TCA-precipitable 3H-PSB was determined in the stomach and small bowel content, 20 and 60 minutes after the administration. The experiment showed more complete inactivation of soy antigen as compared to chick ovalbumin (the authors' data), bovine serum albumin, chick ovomucoid and Kunitz trypsin inhibitor (the literature data). Basing on the results obtained, it is suggested that the soy reserve protein possesses low allergenic properties.

Adult male Wistar rats received protein mixtures containing chick ovalbumin (OVA) intragastrically, whereupon immunoreactive OVA was determined in the chymus of the gastrointestinal tract and in blood serum by the immunofluorescence technique and radioimmunoassay. Combined administration of OVA and the soybean inhibitor of trypsin suppressed the degradation of the antigenic structure of OVA in the intestine and augmentation of immunoreactive protein absorption. The suppression was less pronounced if OVA was combined with chick ovomucoid.

Angiotensinogen (a substrate of renin) was isolated from pig and sheep blood plasma. Content of angiotensinogen was estimated in the preparations obtained by an indirect biological method, which was based on estimation of an increase in blood pressure in rats, caused by angiotensin, liberated from angiotensinogen during incubation with renin. The preparation, obtained by ammonium sulphate fractionation of pig blood plasma, contained 0.4% of angiotensinogen. Angiotensinogen was also isolated from sheep blood plasma using ammonium sulphate fractionation, DEAE-Sephadex chromatography and gel filtration through Sephadex G-100; this preparation contained 10-13% of angiotensinogen.

Pancreatic Kallikrein was purified by affinity chromatography on BPTI-Sepharose. Immobilized BPTI was prepared via three stages: a) formation of the BPTI--acetylated trypsin complex; b) coupling of the resultant complex with CNBr-activated Sepharose; c) dissociation of the bound complex at pH 2.0 to yield immobilized BPTI and acetylated trypsin. The final product contained 59 X 10(-3) micronmoles insolubilized BPTI/ml Sepharose. Trypsin occurring in commercial Kallikrein preparations was separated by the batch procedure with ovomucoid-Sepharose. This method allows 100-fold purification of commercial Kallikrein.

The guinea-pigs kept on standard diet given in animal houses and fed some soluble proteins of animal origin demonstrated circulating anaphylactic antibodies and developed anaphylactic sensitivity (to proteins of chicken eggs, normal equine serum and pasteurized cow's milk) marked by a considerable number of lethal outcomes upon intravenous resolution. The severity of anaphylaxis depends on the nature of allergenic proteins, the sensitizing dose and time of resolution. Allergenic properties of proteins correlate with period of the preservation of the antigenic determinants. Immune induction was found to be selective on animals' sensitization with a mixture of allergenic proteins.

Proteolysis and intestinal absorption of 3H-protein alimentary antigens (bovine serum albumin--BSA and chicken ovalbumin--OVA) administered jointly to the digestive tract of rats were studied. It was shown that antigenic structure of OVA is marked by a far greater resistance in the course of protein assimilation by the body as compared with that of BSA.

A problem of leukotrienes--metabolites of arachidonic acid is reviewed in immunological aspects. Their nomenclature is given; basic pathways of biosynthesis, transformation and mode of leukotriens participation in hypersensitivity and inflammatory reactions are considered. The possibility of application of leukotrienes antagonists and inhibitors of their formation for allergic diseases treatment is discussed.

Adult rats were examined for the time course of inactivation of antigenic determinants of tritium-labeled bovine serum albumin (BSA) or chicken ovalbumin administered intragastrically. Immunoreactive protein in the perfusates was determined according to the amount of the radioactive label retained by the immunosorbent. Antigenic determinants of protein disintegrated very rapidly after protein penetrated the gastrointestinal tract. Within 20 minutes after administration their amount did not exceed 12% of the dose administered. BSA disintegrated more rapidly than ovalbumin. At the same time after 20, 60 and 180 min an insignificant amount (about 1%) of immunoreactive protein penetrated the distal part of the small and large intestines. The amount of high-molecular fragments in all the parts of the gastrointestinal tract exceeded the discovered amount of immunoreactive protein. The data obtained indicate that a small amount of foreign food antigens is capable of overcoming the barrier of the cavitary proteolysis and of reaching those parts of the intestine where they can be absorbed in the intact form.

Rats weighing 290 g each were fasting for 12 days with no changes occurring in the weight of the testicles, total lipids, phospholipids, di- and triglycerides content therein. The cholesterol ethers level increased by 53 per cent and in the composition of di- and triglycerides and the cholesterol ethers the relative content of high-molecular polyunsaturated fatty acids was going up, while the fatty acids composition of the phospholipids remained the same.

A study was made of the effect of complete alimentary fasting of varying duration on barrier permeability of the gastrointestinal tract for chick ovalbumin (OA). Guinea-pigs which fasted for 96, 48 and 12 (control) hours were fed intragastrically 300 mg chick ovalbumin in saline, and after 3 hours immunoreactive OA was measured in blood serum by competitive radioimmunoassay. It was established that fasting of the animals for 96 h led to a significant increase in unchanged food antigen uptake by systemic circulation. The similar increase of OA intake after 48 h of fasting was insignificant. The data obtained can be explained in terms of a decrease in protease activity and inhibition of amino acid uptake by the intestinal epithelium under complete alimentary fasting.

A study was made of the permeability of the gastrointestinal barrier of intact adult rats for bovine serum albumin (BSA) labeled with 3H during antigen administration into an isolated loop of the proximal jejunum and intragastric administration via a probe. The content of the tritium label was determined in the peripheral blood serum and liver cytoplasm obtained upon homogenate centrifugation. The content of the BSA antigenic determinants in biological fluids was determined by immunosorption. In addition, the presence of high-molecular peptides precipitated with trichloroacetic acid was also assayed in the fluids. It was demonstrated that an immunologically significant amount of BSA penetrated the internal medium of the body whatever the route of administration. In all the cases the content of BSA in the liver cytoplasm was significantly higher than in the blood serum. A considerable part of radioactivity falls within the high-molecular peptides. It is inferred that the liver plays the principal role in the deposition and catabolism of foreign antigenic structures.