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Biomedical subjects

V K Mazo

Publications and source records attributed to V K Mazo.

At least 55 records · Page 3Linked to original sources
PubMed1992

[The permeability of the barrier of the gastrointestinal tract for the macromolecules of polyethylene glycol-4000: an assessment of the mechanism and its reproducibility].

Polyethylene glycol (PEG)-4000 is proposed as a tracer of intestinal macromolecular permeability. The reproducibility of permeability testing with PEG-4000 and the mechanism of its penetration through intestinal mucosa were studied in adult rats. Permeability measurement for PEG-4000 was reproducible when repeated twice for 2 days. This makes it possible to repeat PEG-4000 permeability testing before and after any experimental impact on the intestine. I.p. administration of colchicine to rats (125 micrograms/100 g b. w.) significantly inhibited intestinal absorption of PEG-4000 fed to the animals 3 hours later. Hence, PEG-4000 penetration through the intestinal mucosa is mediated by the system of enterocyte cytoplasmic microtubules. Mucosal permeability for PEG-4000 may be consequently considered as a valuable model of permeability for protein macromolecules.

Animals↗
PubMed1985

[Effect of food deprivation on the absorption of chick ovalbumin in adult guinea pigs].

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.

Animals↗
PubMed1984

[Intestinal peptidase content of the mucous coat of the small intestine in dogs].

The content of leucine aminopeptidase, cathepsins B and D was measured in the mucous coating of the small intestine and duodenal juice of adult fistula dogs. It was shown that inhibitory assay was mandatory for measuring the content of intestinal peptidases. The authors discuss the possibility of hydrolysis of food substrates in the parietal layer of the mucous coating by proteolytic enzymes of both intestinal and pancreatic origin.

Animals↗
PubMed1984

[Effect of protein inhibitors of pancreatic proteinases on the breakdown and absorption of immunoreactive chicken ovalbumin in the intestines of adult rats].

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.

Animals↗
PubMedDate not supplied

[The selenium haemostasis during experimental anaphylaxis reaction in rats treated with reduced glutathione and selenium enriched spirulina].

The main events caused by anaphilaxis in selenium haemostasis in rats include significant increase of selenium excretion with urine (6.36 +/- 1.18 nM Se/18 h., n = 10, compared with 1.72 +/- 0.38 nM Se/18 h., n = 10) and decrease of selenium plasma/selenium erythrocytes ratio from 0.939 to 0.791. Reduced glutathione (G-SH) administration led to 1.5-fold decrease of plasma selenium level and 1.3-fold increase of selenium concentration in intestinal walls of sensitized rats (r = -0.720, P < 0.001). Chromatographic separation of plasma proteins showed that intragastric intubation of G-SH to sensibilized rats significantly decreased the protein P content and did not influence the concentration of Se-GSHPx, thus indicating the local selenium acceptor role of G-SH. G-SH administration did not influence the intestinal permeability in sensitised rats while use of complex additive: G-SH and selenium enriched spirulina--normalized the latter parameter and the ratio of protein P/Se-GSHPx in plasma.

Anaphylaxis↗
PubMedDate not supplied

[The effect of starvation on mast cell functional activity and on the content of microsomal cytochromes in the liver].

Histamine secretion and ATP levels were measured in mast cells from the abdominal and pleural cavities of Wistar rat males (250-300 g) which had been starving for 2-4 days. Food deprivation had no effect on histamine levels and secretion in exposure to substance 48/80. ATP concentration got reduced from starvation day 2. Food deprivation for 2 days led to decline in the content of cytochromes P-450, P-450B, in the ratio P-450B/P-450L, but had no effect on rat liver cytochrome B5. 4-day starvation did not entail further changes.

Adenosine Triphosphate↗
PubMedDate not supplied

[The effect of milk consumption on the activity of the formaldehyde detoxification system in sensitization to this compound].

The activity of formaldehyde dehydrogenase (FDG) and total nonspecific formaldehyde oxidative activity of nasal mucosa and liver and the amount of reduced glutathione in the liver were measured in guinea pig subjected to epicutaneous or inhalative action of formaldehyde and additionally fed with cow milk. Glutathione-deficient animals demonstrated an increase in FDG activity following formaldehyde sensitization both in the liver and in nasal mucosa, whereas FDG activity in glutathione-supplied animals did not change significantly. The concentration of formaldehyde in the internal environment is supposed to be controlled by the levels of coenzyme (reduced glutathione) and FDG activity.

Aldehyde Oxidoreductases↗
PubMedDate not supplied

[Experimental evaluation of the allergen activity of a peptide preparation produced from an enzymatic hydrolysate of milk proteins using ultrafiltration].

Noninbred guinea-pig experiments were performed to investigate specific potential allergenicity of cow milk proteins (CMP) consisting of casein (80%) and serum proteins (20%), of low-molecular peptides (LMP 20/80) produced from CMP 20/80 by enzymatic hydrolysis and ultrafiltration; to evaluate nonspecific effect of test diet CMP 20/80 and LMP 20/80 on anaphylactic response of the animals to ovalbumin and histamine LD50. LMP 20/80 versus CMP 20/80 had a hypoallergenic effect. Potential mechanisms of low anaphylactic sensitivity induced by LMP 20/80 are discussed.

Allergens↗
PubMedDate not supplied

[Experience with a selenium-containing biological active supplement used in children with pneumonias in an intensive care unit].

The efficacy of the biologically active additive (BAA) "Spirulin-Sochi-Selen" was evaluated in 45 children aged 3 to 15 years who had acute pneumonia treated in the intensive care unit for infected patients of the Tushino children's city hospital, Moscow. The levels of selenium were determined by the Alfthan microfluorimetric technique (1984). The time course of clinical, laboratory, functional, and X-ray changes was determined. A control group comprised 20 children taking no selenium-containing foods or biologically active additives. The findings suggest that the BAA "Spirulin-Sochi-Selen" is effective as part of therapy for acute pneumonia in children treated in an intensive care unit. There were no signs of selenium deficiency in any case despite the baseline reduction in the average serum levels in both groups.

Acute Disease↗