[Arterial hypertension after heart transplantation].

Aim To evaluate incidence of arterial hypertension (AH) in the posttransplantation period and to identify risk factors for this complication.Materials and methods From January, 2010 through December, 2017, 96 heart transplantations (HT) (70 men and 26 women aged 46.5±13.9 years) were performed. During the first month following HT, 8 recipients died and were excluded from the analysis. The retrospective evaluation of results included 88 patients followed up for more than one year.Results For the entire post-HT period (maximum 92 months), AH was observed in 75 of 88 (85%) recipients. Post-HT AH was correlated with male gender (r=0.24; p=0.031), history of smoking before HT (r=0.45; p<0.001), history of ischemic heart disease (IHD) (r=0.28; p=0.01), older age (r=0.35; p=0.001), higher body weight index (r=0.37; p=0.0005), creatinine level (r=0.37; p=0.001), and low-density lipoprotein cholesterol level (r=0.27; p=0.04). Interrelations with other AH risk factors were not found. Most patients developed AH within the first two years after HT. During the first year, AH was diagnosed in 60% (53 of 88) of patients (relapse, 85% (n=29); newly diagnosed, 45% (n=24), p=0.0003). At two years, AH was detected in 79% (46 of 58) of patients (relapse, 53% (n=18); newly diagnosed, 53% (n=28), p=0.9). All recipients received an adequate antihypertensive therapy. 40-63% of patients required a single-drug therapy at different points of follow-up; from 29 to 45% of patients required a two-drug therapy, and 5-15% of patients required three or more drugs. During all 5 years of treatment, most patients used angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) (70-87%) and slow calcium channel blockers (SCCB) (48-53%). The presence of AH following HT was associated with development of all cardiovascular events (CVE; r=0.31; p=0.012) whereas persistent AH, which required a combination antihypertensive treatment, was associated with a high mortality (r=0.61; p=0.015).Conclusion AH is a frequent complication of HT (85%), which is newly diagnosed in most patients during the first two years. AH incidence was higher for male recipients with a history of IHD, hypertension, and smoking. Approximately half of patients required only a single-drug antihypertensive therapy. After HT, the most frequently prescribed drugs included ACE inhibitors or ARBs and SCCBs (70-87% and 48-53%, respectively, depending on the time elapsed after HT). Persistent AH requiring a treatment with two or more antihypertensive drugs was associated with development of all CVEs and a higher long-term mortality.

Structural and Functional Analysis of the Small Intestine in Rats After Six-Month-Long Exposure to Multiwalled Carbon Nanotubes.

Structural and functional analysis of the small intestinal villi in outbred rats was performed after treatment with multiwalled carbon nanotube suspension in comparison with the effects of fine charcoal suspension. Chronic (6 months) exposure to nanotubes in a concentration of 0.2 mg/liter and, particularly, 0.5 mg/liter induced significant changes in the small intestine manifested in a decrease in the number of villi without changes in the brush border integrity, increase in the number of destructed villi, and appearance of villi with apical necrosis. These abnormalities were not observed after treatment for a shorter period of time (2 months).

[Morphological comparative assessment of in vivo 2-week oral exposure of silver nanoparticles and silver sulfate on the mice liver].

Currently the problem of the impact of nanoparticles and nanomaterials on human health remains to be poorly understood. As in our studies of the impact of silver nanoparticles on rats liver as well in works of other researchers there were investigated morphofunctional indices under peroral exposure. Although all researchers took different sizes, doses and concentrations of silver nanoparticles, various exposure time and different stabilizers, the same effects had been obtained, which, however, were occurred under both different doses and time of exposure. However, it was interesting to compare the impact of silver nanoparticles with reference substance - silver sulfate on the mice liver with the previously evaluated effect produced on the rats ' liver. By ourselves there was executed the morphological comparative evaluation of in vivo oral 2-weeks exposure of 4 concentrations (0.1; 5; 50 and 500 mg/l) of silver nanoparticles with size of 14 nm, stable arabian gum 1:7 by weight, and of 4 similar concentrations of silver sulfate on the liver of male mice СВАхС57В1/6 weighing 25-35g. 2 groups were considered as control: intact mice and mice received gum in water. Results of the exposure were assessed according to 10 morphological and functional indices. The impact of nanosilver was shown to initiate from its concentration of 50 mg/l and to express in the gain of the index of alteration of the cytoplasm of hepatocytes with the increasing in both severity of steatosis and the number of micronecroses, persisting at the same level at concentrations of 500 mg/l and with the elevation of the index of alteration of nuclei of hepatocytes, while the similar effect develops under the influence of silver sulfate at a concentration of 500 mg/l only. The remaining investigated morphofunctional indices did not differ significantly in all groups of mice. Unlike previously executed studies on rats, mice appeared to be sensitive to the effects of nano-silver more than to silver sulfate.

[Morphofunctional cell assessment of dynamics of silver nanoparticles exposure on the rat liver].

There was investigated the dynamics of 1-, 3- and 6-month exposure to 4 doses of silver nanoparticles of size 14.3 +/- 0.05 nm stabilized with gum arabic, and 4 doses of silver sulfate on the liver of male outbred rats by 13 cell morphofunctional indices. As the solvent to obtain a working solution there was used distilled water solutions of different conccentrations were obtained on the base of Moscow tap water cleaned out by a charcoal filter. The animals had free acccess to the drinkers with the studied water. For silver sulfate as a control intact rats served, for silver nanoparticles--acacia gum. The increase in the number of polyploid hepatocytes, micronekroses and discomplexation of hepatic beams and the decreasing the number of reticular endothelial system cells in the liver were shown to permit to evaluate the effect of 6-month nanosilver exposure to the liver at a dose of 0.3 mg/kg as pronounced harmful (Fel), 0.023 mg/ kg--as LOAEL, and 0.0028 and 0.0006 mg/kg--as NOEL. The effect of silver sulfate in doses of 0.28 and 0.03 mg/ kg is assessed as pronounced harmful (Fel), 0,0028 mg/kg--as LAOEL and 0.0005 mg/kg--as NOEL. More earlier detection of toxicity of silver sulfate as Fel (at 3 months) and in smaller doses indicates its greater toxicity to the liver than silver nanoparticles.

Mutagenic activity of acrylamide in the rat thyroid cells under conditions of a subacute experiment.

Experimental mutagenic effect of acrylamide on thyroid gland cells was studied by an extended micronucleus test. Acrylamide in doses corresponding to 0.004-0.1 LD(50) increased the incidence of thyroid follicular cells (A-cells) with micronuclei and other karyological parameters in exposed rats after hemithyroidectomy. This cytogenetic effect allows regarding acrylamide as a mutagen for the thyroid gland and as a carcinogen for this organ.

Effective selection of Proteus mirabilis clones producing mirabilicin D-52.

From a defective-lysogenic Proteus mirabilis strain we isolated several clones differing in the pattern of their growth on agar plates. Using electron microscopy we have shown some of the selected clones to be efficient in producing mirabilicin D-52 after UV induction, while other clones produced defective mirabilicin polysheaths and polycores. Clones producing polysheaths and polycores can be detected electron microscopically only, since these defective particles are biologically inactive.

Electron microscopy of phages liberated by megacin A producing lysogenic Bacillus megaterium strains.

Mitomycin C was added at fairly high concentration (5-10 mug/ml) to exponentially growing cultures of selected strains of Bacillus megaterium. Lysis of the bacteria followed, associated by liberation of phage and megacin A production. In contrast, a low concentration (0.5 mug/ml) of mitomycin induced only megacin A production. Electron microscopic examination of the lysates induced by 5-10 mug/ml of mitomycin in 19 strains of B. megaterium showed them all to contain phages; most of the strains proved polylysogenic. Their lysates contained distinct complete phages of different structures and dimensions. A few strains released defective phage particles. The significance of the electron microscopic findings is discussed in relation to megacinogeny.