The level and activity of molecular forms of monooxygenase P-450b and P-450c during their separate and consecutive induction in the liver

Studies with monospecific antibodies to individual forms of monooxygenases P-450b (phenobarbital-induced) and P-450c (3-methylcholanthrene-induced) by immunochemical, kinetic and spectral methods revealed differences in the dynamics of xenobiotic-induced changes in the content and monooxygenase activity of the total microsomal CO-binding hemoprotein and of its molecular forms. Correction was made in the estimation of the benzphetamine-demethylase and benzpyrene-hydroxylase activities based on the content of specific forms of P-450b and P-450c. Since consecutive injection of phenobarbital and 3-methylcholanthrene (or vice versa) is accompanied by selective induction of the corresponding isoforms and the redistribution of the relative content of P-450b and P-450c in the total pool of cytochrome P-450 in rat liver microsomes, a conclusion was drawn that these molecular forms are induced by different populations of hepatocytes. This conclusion was confirmed by data from immunohistochemical analysis.     

Formation of mevalonic acid, sterols and bile acids from [1-14C]acetyl-CoA and [2-14C]malonyl-CoA in the liver of rabbits with experimental hypercholesterolemia

The effect of cholesterol diet on the rate of mevalonic acid biosynthesis from 1-14C acetyl-CoA, 2-14C malonyl-CoA and the incorporation of these substrates into sterols and bile acids in rabbit liver were studied. Simultaneously, the activities of 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CoA reductase) and acetyl-CoA carboxylase and the biosynthesis of fatty acids from acetyl-CoA and malonyl-CoA were measured. Hypercholesterolemia was found to be concomitant with the inhibition of acetyl-CoA carboxylase activity only in cell-free (700 g) and mitochondrial fractions and slightly decreased the incorporation of acetyl-CoA and malonyl-CoA into fatty acids in the postmitochondrial fraction. The HMG-CoA reductase activity in all subcellular fractions except for the postmicrosomal one was inhibited under these conditions. A significant decrease of acetyl-CoA incorporation and an increase in malonyl-CoA incorporation into mevalonic acid in all liver fractions except for microsomal one were observed in rabbits with hypercholesterolemia. These data provide evidence for the existence of two pathways of mevalonic acid synthesis from the above-said substrates that are differently sensitive to cholesterol. Cholesterol feeding resulted in a decreased synthesis of the total unsaponified fraction including cholesterol from acetyl-CoA, malonyl-CoA and mevalonic acid. The rate of incorporation of these substrates into lanosterol was unchanged. All the indicated substrates (acetyl-CoA, malonyl-CoA, mevalonic acid) are precursors of bile acid synthesis in rabbit liver. Cholesterol feeding and the subsequent development of hypercholesterolemia resulted in bile acid synthesis stimulation, preferentially in the formation of the cholic + deoxycholic acids from these precursors.     

CD14 C-159T and early infection with Pseudomonas aeruginosa in children with cystic fibrosis

Early acquisition of Pseudomonas aeruginosa is associated with a poorer prognosis in patients with cystic fibrosis. We investigated whether polymorphisms in CD14, the lipopolysaccharide receptor, increase the risk of early infection. Forty-five children with cystic fibrosis were investigated with annual bronchoalveolar lavage (BAL) and plasma sCD14 levels. Plasma sCD14 levels were significantly lower in children from whom P.aeruginosa was subsequently isolated (492.75 μg/ml vs. 1339.43 μg/ml, p = 0.018). Those with the CD14 -159CC genotype had a significantly increased risk of early infection with P.aeruginosa suggesting that CD14 C-159T plays a role in determining the risk of early infection with P.aeruginosa.     

The effect of "social stress" during rat pregnancy on the anxiety level of the progeny

Anxiety and locomotion were studied in offsprings of female rats subjected to everyday stress (one a day being displaced into another cage with pregnant rats) during the 3d stage of pregnancy. At the age of 1 month, the prenatally stressed rats had higher anxiety and lower locomotion in comparison with control animals. At the age of 3 month, the prenatally stressed females did not significantly differ from the control in the level of anxiety and locomotion, while the males demonstrated lower ambulation than the control animals.     

Products of the photolysis of 3,6-dichloropicolinic acid (the herbicide lontrel) in aqueous solutions

We studied the composition of products of the photochemical degradation of 3,6-dichloropicolinic acid (DCPA), the active principle of Lontrel, a herbicide broadly used in agriculture. Ultraviolet irradiation (mimicking the natural sunlight action) did not degrade DCPA completely to environmentally safe products. The rate of DCPA degradation was notably lower when distilled water was replaced by river water and even lower in sea water. Chromatomass spectrometry revealed 9 compounds among the photolysis products, in addition to undegraded DCPA.     

Polarographic study of cell respiration in a tissue culture

A simple procedure for measuring the cells respiration without their transformation into the suspension, is suggested: seven glass slides with the cell culture of PKEV (pork, kidney, embryo, versen) are placed into the polarographic cell. Under these conditions the oxygen electrode easily records the fall of oxygen tension in the polarographic cell due to the respiration of 10(5) cells. Oxygen consumption is linear in time at the O2 concentration within the range from 480 to 200 nanoatoms per 1 ml of medium. The respiration rate is found to be enhanced by uncoupler and suppressed by the inhibitors of the electron flow chain (NaCN, antimycin A, amytal, rotenone) and mitochondrial ATPase (oligomycin and diciclohexylcarbodiimide). The above approach enables to evaluate the mitochondrial respiration of any cell monolayer keeping the cells intact.     

The development of connections in the tecto-thalamo-telencephalic visual system of the brain in 13-day-old chick embryos

Light and electron microscopic studies have been made on degenerative changes in the nervous tissue induced by experimental destruction of the median brain bulb at the 5th day of incubation, in parts of the tecto-thalamo-telencephalic visual system in 13-day chick embryos (in the visual tectum, round nucleus of the thalamus and ectostriatum of the telencephalon). It was shown that to this period tecto-thalamic connections are already formed in the visual system, whereas thalamo-telencephalic connections are, presumably, indirect ones.     

The ultrastructural characteristics of the bronchial mucosa in chronic inflammation in participants in the cleanup of the aftermath of the accident at the Chernobyl Atomic Electric Power Station]

Bronchial biopsies from persons exposed to radiation after the Chernobyl accident with clinically verified chronic bronchitis were studied by electron microscopy. The results demonstrate transformed alterative, compensatory-adaptive and inflammatory reactions in bronchial mucosa of contingent. Nevertheless, their integral significance does not alter the nosologic form, and some structural equivalents have dynamic expression.     

Hyperbaric oxygenation and drug therapy in treatment of nonspecific ulcerative colitis and Crohn's disease]

Patients with nonspecific ulcerative colitis and Crohn's disease were treated with drug therapy (prednisolone, sulphasalazine, metronidazole per os and hydrocortisone per rectum) and subjected to 12 sessions of HBO. Every 10-14 months the HBO course was repeated. After 7 years of such a treatment a gradual partial recovery of large intestine mucosa and in some cases even its absolute recovery were observed. It was most difficult to get good results when treating lesion of distal colon segments. HBO produced a good effect when the disease was diagnosed at the early stage, when the intestine injury was accompanied by hepatobiliary system disease and in teenagers.