[The impact of antihypertensive therapy on cerebral hemodynamics in patients with metabolic syndrome].

The aim of this work was the scintigraphic study of brain perfusion and the elucidation of the relationship between daily variations of arterial pressure (AP) and the results of single photon emission computed tomography (SPCT) of the brain in patients with metabolic syndrome (MS). The secondary objective was to estimate effect of combined antihypertensive therapy on cerebral circulation. 24 patients with MS underwent SPCT with 99mTc HMPOA and 24 hr AP monitoring before and 6 mo after therapy with long-acting verapamil combined with slow-release indapamide or enalapril. It was shown that all the patients suffered disturbances of regional cerebral blood flow even in the absence of focal neurological symptoms. Perfusion was especially impaired in the temporal, occipital and superior frontal lobes. The degree of the night-time fall in AP was related to the level of perfusion in the right temporal region (r = -0.5; p = 0.04) which confirms the danger of extreme AD decrease in hypertonics during sleep. Combined antihypertensive therapy has positive influence on cerebral perfusion. Verapamil plus enalapril has more pronounced effect than verapamil plus indapamide on cerebral blood flow in many brain regions.

[Comparative characteristics of revealing hibernated myocardium by means of perfusion and metabolic scintigraphy].

OBJECTIVE: comparative assessment of the informative value of the methods of perfusion and metabolic single-photon emission computed tomography (SPECT) in detecting the hibernated myocardium. MATERIALS AND METHODS: the study included a total of twenty six patients diagnosed with coronary artery disease (CAD). Of these, there were 24 men and 2 women, mean age 52.0±7.0 years. All the patients in order to detect the viable myocardium were subjected to perfusion scintigraphy of the myocardium with (99)mTc-technitrile («Diamed¼, Russia) at rest and in a combination with the nitroglycerine test, as well as metabolic scintigraphy of the myocardium with (123)I-labelled beta-methyl-ρ-iodophenyl pentadecanic acid (BMIPP). RESULTS: the studies showed that sensitivity of myocardial scintigraphy with (99)mTc-technitrile on the background of the nitroglycerine test amounted to 89%, with specificity of 85% and diagnostic accuracy of 86%. While calculating the diagnostic significance of SPECT with (123)I-BMIPP, in turned out that the method's sensitivity amounted to 94%, specificity to 87%, and diagnostic accuracy to 91%. CONCLUSION: perfusion scintigraphy of the myocardium on the background of the nitroglycerine test and scintigraphic assessment of metabolism of fatty acids are highly informative tests for revealing viable portions of the ischemic myocardium, with the diagnostic parameters of SPECT with (123)I-BMIPP being slightly superior to those of perfusion scintigraphy with (99)mTc-technitrile on the background of sublingual administration of nitroglycerine.

[Scintigraphic evaluation of cerebral circulation in prognosis of cerebrovascular complications of coronary artery bypass grafting].

The aim of the work was to study the possibility of using single-photon emission computed tomography (OECT) of brain using 99m Tc-hexamethyl propylene aminoxime for the evaluation of long-term prognosis of the development of neurocognitive deficit after coronary artery bypass grafting (CBG) and elucidation of relationship between variations of cognitive function and regional cerebral circulation. Surgical myocardial revascularization under artificial circulation was performed in 22 patients with CHD. All of them were examined for the assessment of neurologic and neuropsychological status, and OECT data before, 14 days and 6 months after CBg. Early cognitive deficit developed in 96% of the patients and persisted for 6 months in 55%. Cognitive dysfunction was manifest as post-operative impairment of short- and long-term memory, and general efficiency of remembering. Visual memory and psychomotor speed also deteriorated. Cerebral circulation decreased in frontal and parietal lobes of the right hemisphere. Deterioration of long-term memory 6 months postoperatively correlated with the early circulation decrease of in the right and left temporal lobes.

[Cognitive dysfunction and brain perfusion in patients with arterial hypertension: possibilities of pharmacological therapy].

The study included 31 patients with essential hypertension. Twenty-four hours blood pressure monitoring, assessment of neurological status and cognitive functions as well as single photon emission tomography were performed at baseline and three months after treatment. The beta-blocker therapy during 3 months exerted a positive effect on the brain perfusion that resulted in the improvement of cognitive function - verbal and visual memory, attention, psychomotor speed, thinking and visuoconstruction.

[Cerebral perfusion in patients with arterial hypertension associated with type 2 diabetes].

The aim of the study was to assess cerebral perfusion (CP) in patients with arterial hypertension in combination with type II diabetes. The subjects were 57 patients with stage II AH (mean age 51.6 +/- 5.7 years), among who there were 33 patients without disturbances in carbohydrate exchange and 24 patients with compensated or subcompensated type II diabetes. All the patients underwent single-photon emission computed tomography of the brain with 99m Tchexamethylpropyleneamineoxime. The study showed that patients suffering from AH with or without type II diabetes had signs of cerebral hypoperfusion and lowered cerebrovascular reserve even in the absence of focal neurological symptoms. Disturbances in cerebral perfusion were more prominent in patients suffering from AH with type II diabetes vs. patients without carbohydrate exchange disorder.

[Hypotensive activity and cerebroprotective properties of carvedilol in patients with arterial hypertension associated with type 2 diabetes mellitus].

Aim of the study was to elucidate peculiarities of influence of carvedilol on 24-hour blood pressure (BP) profiles and changes of parameters of cerebral perfusion in patients with arterial hypertension (AH) associated with type 2 diabetes mellitus. Investigations were performed in 30 patients with I-III degree AH associated with type 2 diabetes of compensation and subcompensation stages. At baseline and after 24 weeks of treatment with carvedilol we carried out 24-hour BP monitoring, single photon emission computer tomography of the brain, and assessed the state of carbohydrate and lipid metabolism. According to data of 24-hour BP monitoring marked lowering of BP parameters occurred under the influence of therapy. This was accompanied with 26% decrease of the number of hypoperfused sectors of the brain (chi2=6.04, =0.014). During adenosine test number of hypoperfused sectors decreased from 136 to 117 (chi2=2,10, =0,147) what evidenced for a tendency to improvement of reactivity of cerebral vessels in response to vasodilating influences. The preparation exerted favorable effect on metabolic parameters and lowering of level of postprandial glycemia in dynamics of treatment was statistically significant.

Central hemodynamic and cognitive function in the short- and long-term periods after coronary bypass grafting.

The aim of the present work was to study cerebral hemodynamics and cognitive function in patients suffering from coronary artery disease (CAD) in the short- and long-term periods after coronary bypass grafting (CBG). The study accrued 65 patients who underwent myocardial revascularization using cardiopulmonary bypass (43 persons) and without heart interruption (22 persons). In 21 cases, CBG using cardiopulmonary bypass with a purpose of preventing cerebral events was supplemented by administration of instenon manufactured by the Nycomed Company, Perfusion tomoscintigraphy of the brain and neuropsychological testing were provided to all the patients prior to CBG, 14 days and 6 months following surgery. CBG coupled with preventive administration of instenon or beating heart operation allow to appreciably minimize the risk of disorders of cerebral hemodynamics and cognitive function in the long-term postoperative period.

[Anti-ischemic effects of trimetazidine in patients with post-infarction heart failure]. / Anti-ishemicheskaia éffektivnost' trimetazidina u bol'nykh s postinfarktnoi serdechnoi nedostatochnost'iu.

The antiishemic efficiency of course monotherapy with trimethazidine and its impact on myocardial perfusion were studied in patients with postinfarct dysfunction of the left ventricle (LV), which was associated with moderate heart failure (HF). This prospective controlled clinical study included 47 patients who had experienced myocardial infarction. The patients had also angina pectoris on exertion and NYHA Functional Classes (FC) II-III HF. The patients were randomized into 2 groups: Group 1 comprised patients with more than 50-W exercise tolerance (ET), FC II angina, and FC II HF; Group 2 consisted of those with 50-W or less ET, FC II-III angina, and FC II-III HF. Four-week course therapy with trimethazidine in a dose of 60 mg/day was found to exert a pronounced antiischemic effect in patients with reversible LV ischemia associated with HF. The tolerance of the drug during its 4-week course therapy was good and the drug caused no adverse reactions.

Scintigraphic evaluation of myocardial and cerebral blood flow in patients with a history of coronary artery bypass grafting.

This paper deals with a comparative scintigraphic evaluation of the changes that occur in coronary and cerebral circulation in patients with coronary artery disease (CAD) after coronary artery bypass grafting (CABG) under conditions of cardiopulmonary bypass (CPB) or beating heart. Twenty-nine CAD patients who underwent CPB were examined. Of these, 14 patients were operated on using CPB (the first group) and 15 patients on the beating heart using the myocardial "stabilizer" Octopus (the 2nd group). The patient groups matched in terms of the age, sex, the clinical and angiographic factors. Perfusion scintigraphy of the heart and brain by means of single-photon emission computed tomography (SPECT) and the neurologic evaluation were performed twice in all the patients: before and 2-4 weeks after CABG. The second group patients demonstrated a significant lowering of the mean magnitude of stable defects (SD) of myocardial perfusion. The lowering or disappearance of SD was observed in a greater percentage of cases versus the first group. All the patients were found to have areas of hypokinesis in the SD projection. Also, the second group showed a significant rise of the mean magnitude of left ventricle ejection fraction. Operations with CPB were associated with a 5% decrease of cerebral blood flow in the frontal and temporal lobes of the right hemisphere. No significant deterioration of brain perfusion was observed in patients (on the whole in the group) operated on without heart arrest. It is noteworthy that there was a significant improvement of the average group indicators of cerebral perfusion in the right occipital and posterior segments of the temporal lobes. The changes in cerebral perfusion were in agreement with the course of changes in the cognitive status. Thus, CABG on the resting heart in CAD patients favours a more remarkable restoration of perfusion and contractility of the hibernated myocardium versus revascularization performed under CPB and exerts, as a result, a beneficial effect on cerebral circulation and the neuropsychological status of the patients.

[Cerebral microcirculation and structural changes in the brain in essential hypertension]. / Tserebral'naia mikrotsirkuliatsiia i strukturnye izmeneniia golovnogo mozga pri essentsial'noi gipertonii.

The purpose of the study was to examine cerebral microcirculatory and structural changes in 32 patients (20 males and 12 females whose age varied from 37 to 63 years) with moderate arterial hypertension (AH). All the patients underwent single-photon emission computed tomography of the brain, using (99m)Tc-hexamethylpropyleneaminoxylfor the evaluation of perfusion, as well as magnetic resonance imaging for the examination of cerebral structures. Cerebral structural changes and perfusion impairments were detected in patients with AH, even if they had no clinical signs of cerebrovascular insufficiency. Inadequate blood flow most frequently occurred in the parietal and temporal regions of the brain. There was a reduction in the cerebrovascular reserve in the frontal lobes in AH.

[Pharmacological prevention of cerebrovascular complications in cardiac patients after coronary artery bypass surgery]. / Medikamentoznaia profilaktika tserebrovasculiarnykh oslozhnenii u bol'nykh ishemicheskoi bolezn'iu serdtsa posle aortokoronarnogo shuntirovaniia.

The aim of the study was to evaluate cognitive functions and cerebral perfusion in cardiac patients following coronary artery bypass graft surgery (CABG) and to investigate a potential of pharmacological prevention of neurocognitive deficit and cerebral perfusion disorders. Forty patients undergone CABG with cardiopulmonary bypass (CPB) were included in the study. For prevention of cerebral perfusion impairments and cognitive deficit, instenon ("Nycomed") was administered to 18 of the patients. The results revealed that the use of instenon allowed reducing a negative effect of CABG with CPB on neuropsychological state of the patients, thus preventing cerebral perfusion disturbances during surgery intervention.

[Patterns of cerebral blood flow reactivity in adenosine stress-test in patients with carotid stenosis evaluated with MRI and emission tomography with 99m Tc-HMPAO]. / Otsenka reaktivnosti krovotoka golovnogo mozga s pomoshch'iu adenozinovoi proby u patsientov so stenozom sonnykh arterii, po dannym MRT i émissionnoi tomografii s 99m Tc-GMPAO.

In this study we evaluated the adenosine stress-test combined with 99mTc-HMPAO SPECT as a possible tool for evaluation of brain perfusion reserve in patients with various degrees of cortical neurologic damage due to internal carotid artery stenosis. The investigation comprised 37 patients with atherosclerotic carotid disease, in everybody of whom the stenosis was detected by echo-Doppler study of carotids and later in 28 verified also using invasive intraarterial digital subtractive angiography. In everybody the 99mTc-HMPAO SPECT study was performed twice: at rest and during stress-test with intravenous injection of adenosine with the patient in the supine position. It was gathered three groups of patients with different kinds of cerebral blood flow reactivity in adenosine stress-test. Henceforth, we conclude that, first, the 99mTc-HMPAO SPECT adenosin stress challenge of cerebral blood flow is a reliable functional test for every group of patients with extensive atherosclerosis and can be used for detection of patients with exhausted or decreased cerebral perfusion reserve in whom the risk of future cerebral vascular ischaemic events is elevated.

[Effect of oligoribonucleotides specifically bound by E. coli RNA-polymerase on DNA-dependent RNA synthesis]. / Vliianie oligoribonykleotidov, izbiratel'no sviazyvaemykh RNK-Polimerazoi E. coli na DNK-zavisimyi sintez RNK:

It was shown previously that E. coli RNA-polymerase (EC 2.7.7.6) selectively binds certain fractions of penta- or hexaribonucleotides random mixtures (Knorre V. L., Vasilenko S. V., Salganik R. I., FEBS Lett., 30, 229, 1973). The data obtained demonstrate that such oligoribonucleotides compete with DNA for the RNA polymerase active centre and inhibit DNA dependent RNA synthesis catalyzed by the enzyme. These properties are absent in tri- and tetraribonucleotides which cannot be bound by RNA polymerase. The inhibitory action of the pentaribonucleotides was higher when they had been added prior to DNA to the mixture containing RNA polymerase.