[Prokaryotic Argonaute Proteins as a Tool for Biotechnology].

Programmable nucleases are the most important tool for manipulating the genes and genomes of both prokaryotes and eukaryotes. Since the end of the 20th century, many approaches were developed for specific modification of the genome. The review briefly considers the advantages and disadvantages of the main genetic editors known to date. The main attention is paid to programmable nucleases from the family of prokaryotic Argonaute proteins. Argonaute proteins can recognize and cleave DNA sequences using small complementary guide molecules and play an important role in protecting prokaryotic cells from invading DNA. Argonaute proteins have already found applications in biotechnology for targeted cleavage and detection of nucleic acids and can potentially be used for genome editing.

Prokaryotic Argonaute Proteins as a Tool for Biotechnology.

Programmable nucleases are the most important tool for manipulating the genes and genomes of both prokaryotes and eukaryotes. Since the end of the 20th century, many approaches were developed for specific modification of the genome. The review briefly considers the advantages and disadvantages of the main genetic editors known to date. The main attention is paid to programmable nucleases from the family of prokaryotic Argonaute proteins. Argonaute proteins can recognize and cleave DNA sequences using small complementary guide molecules and play an important role in protecting prokaryotic cells from invading DNA. Argonaute proteins have already found applications in biotechnology for targeted cleavage and detection of nucleic acids and can potentially be used for genome editing.

Mechanisms of Stress Resistance and Gene Regulation in the Radioresistant Bacterium Deinococcus radiodurans.

The bacterium Deinococcus radiodurans reveals extraordinary resistance to ionizing radiation, oxidative stress, desiccation, and other damaging conditions. In this review, we consider the main molecular mechanisms underlying such resistance, including the action of specific DNA repair and antioxidation systems, and transcription regulation during the anti-stress response.

[Immunomorphological study of angiotensin-converting enzyme in coronary shunts].

Coronary bypass surgery is the operation of choice in patients with coronary atherosclerosis. However, some time later, venous shunts frequently stop functioning after successful surgery. The reasons for this include intimal hyperplasia occurring in response to release of cytokines, angiotensin II in particular. In man, the latter is formed by angiotensin-converting enzyme or chimase. The findings show that elevated ATF concentrations are found in some cells in the area of intimal hyperplasia, in macrophages and smooth muscle cells of the shunt hyperplastic intima. The increased ATF concentration in the aorto-coronary shunt cells results in the elevated levels of angiotensin II, the migration of smooth muscle cells, their hypertrophy and hyperplasia, the formation of atherosclerotic plaques, thrombosis, and circulatory disorders.

[Pneumonia in patients with acute brain stroke].

One hundred and thirty-two patients, 86 men and 46 women, aged from 46 to 78 years, mean age 67 +/- 9 years, with ischemic stroke have been studied, the diagnosis confirmed using CT or section study. Pneumonia was developed in 15 (11%) of patients, its frequency was significantly higher in patients with hemorrhage stroke and brain infarction of the complex genesis as compared with other types of stroke (chi2 = 10.42, p < 0.05). Pneumonia was developed more often in patients with total infarction in the system of inner carotid artery than in patients with partial infarction in the carotid system (26.9 and 4.8%, respectively, p < 0.05) as well as in patients with consciousness and swallowing disorders in the acute period of disease. The correlation between the frequency of pneumonia and neurologic deficit has been studied. Higher mortality and disability rates were observed in the group of patients with pneumonia.

[Acute damage to the myocardium and left lung is a complication of high-frequency percutaneous thermoablation of solitary metastasis of renal cancer into the liver (a clinical observation)].

The paper describes a case of severe complication of radio-frequency percutaneous thermoablation of renal metastasis into the liver, which occurred in a young woman with the intact cardiovascular system and manifested itself in the development of alveolar edema of the lung and acute dilation of the stomach. Pulmonary edema resulted from left ventricular myocardial and pulmonary parenchymal lesions and acute mitral valvular insufficiency. The authors' considerations as to the possible cause and mechanisms of development of this life-threatening complication first described in the literature are also given.

Detection of circulating stromal stem cells with osteogenic potential in the blood of coronary patients by laser flow cytometry.

The number of cells expressing antigen to osteonectin was appreciably increased in the blood of coronary patients, but no cells of this kind were detected in donors. The number of CD34+ stem cells in these patients virtually did not differ from that in normal subjects. A close relationship between atherosclerosis development and presence of stromal stem cells with osteogenic potential in the blood is hypothesized.

[Immunomorphological study of coronary grafts].

Most patients subjected to coronary artery bypass grafting develop graft occlusions in some time after successful coronary surgery. Causes of graft occlusions comprise hyperplasia of intima occurring as a response to release of cytokines and angiotensin II. Angiotensin II is formed in human body with participation of angiotensin converting enzyme (ACE) or chymase. We found high concentrations of ACE in some smooth muscle cells in hyperplasia zone. Proliferation of smooth muscle cells, their hypertrophy and increased synthesis of intercellular space proteins facilitate graft occlusion. Moreover ACE was found in cytoplasm of macrophages infiltrating graft's intima. Thus ACE can be an important contributor to the process of coronary artery bypass graft obstruction.

[Dynamics of heart rate variability in ischemic heart disease patients after coronary artery bypass grafting]. / Dinamika variabel'nosti ritma serdtsa u bol'nykh ishemicheskoi bolezn'iu serdtsa posle operatsii koronarnogo shuntirovaniia.

AIM: To study dynamics of 24-hour heart rate variability (HRV) after coronary artery bypass grafting (CABG) and to elucidate relationship between HRV dynamics and clinical course of the disease. METHODS AND MATERIAL: A novel methodological approach to evaluation of HRV based on measurement of mean weighted rhythmogram variation (MWRV) was implemented. Ninety patients were studied before CABG. Then HRV was assessed in 2 weeks (61 patients), 2 (45 patients), 6 (24 patients)and 12 (33 patients) months after surgery. RESULTS: At all study points HRV was lower in CHD patients than in healthy persons. Substantial lowering of average MWRV 2 weeks after surgery was followed by return to preoperative level by the end of 2 months, leveling off until 6 months and some decline by the end of a year. Individual changes of MWRV were assessed in 29 patients in whom HRV was evaluated at 5 or 4 study points. Three types of MWRV changes were distinguished: type 1 - "normal" dynamics (9 patients) - elevation of MWRV 2, 6 and 12 months; type 2 (10 patients) - elevation of MWRV after 2 and 6 months with subsequent lowering by the end of 1 year; type 3 (10 patients) - lowering of MWRV In 2 and/or 6 months. The following relationships between MWRV changes and clinical course after surgery were observed: there were no complications among patients with type 1 MWRV dynamics; 8 of 10 type 2 patients had signs of heart failure, or blood pressure elevation, or recurrence of angina by the end of 1 year: among 10 type 3 patients 6 experienced various complications. Recurrence of angina at various intervals after CABG occurred in 5 patients and in all it was associated with MWRV decrease. CONCLUSION: Pronounced decrease of MWRV between 2 and 12 months after CABG is associated with worse clinical course and its detection should trigger additional investigation and care of a patient.

[Heart rate variability before and after coronary artery bypass surgery in patients with ischemic heart disease]. / Variabel'nost' ritma serdtsa do i posle operatsii koronarnogo shuntirovaniia u bol'nykh ishemicheskoi bolezn'iu serdtsa.

Short term heart rate variability (HRV) was studied in 44 patients before, in 2 weeks and 2 months after coronary artery bypass grafting (CABG). Prior to surgery the patients were divided into 2 groups: with normal and substantially lowered HRV parameters. In 2 weeks after CABG lowering of HRV was registered in all patients. In 2 months parameters of HRV returned to preoperative level almost in all patients but did not exceed it despite restoration of coronary blood flow and improvement of myocardial contractility. Intergroup differences of characteristics of HRV remained the same as before CABG.

[Detection of natural anti-angiotensin converting enzyme antibodies in human serum using immunoenzyme technique ]. / Opredelenie estestvennykh antitel k angiotenzinprevrashchaiushchemu frmentu v syvorotke krovi cheloveka immunofermentnym metodom.

Solid-phase enzyme immunoassay (EIA) was developed for detecting natural antibodies to angiotensine-converting enzyme (ACE). Optimal conditions for detecting natural anti-ACE by EIA in the sera of donors and patients with disorders of arterial pressure are selected. The findings indicate that the level of natural anti-ACE is normally constant, while in the patients it is increased in 50% cases.

[Fixation of the endocardial electrode in cardiac pacing]. / K voprosu fiksatsii éndokardial'nogo élektroda pri élektricheskoi stimuliatsii serdtsa.

The late outcomes of continuous endocardial pacing surgery were studied in 34 patients when various approaches were used to fix a proximal endocardial electrode. When fixed to a vein or its adjacent tissues, the electrode remained to be stable while raising hands. When fixed to the cephalic vein, this procedure was accompanied by the displacement of the endocardial electrode and the appearance of X-ray signs of electrode instability. The new procedure for fixing the proximal electrode contributes to the stability preservation of the intracardiac part of an endocardial electrode.

[Dynamics of physical exercise tolerance in patients with ischemic heart disease during the 1st year after direct myocardial revascularization operation]. / Dinamika tolerantnosti k fizicheskoi nagruzke u bol'nykh ishemicheskoi bolezn'iu serdtsa v techenie 1-go goda posle operatsii priamoi revaskuliarizatsii miokarda.

The bicycle ergometric testing was performed in different periods within the first year of direct myocardial revascularization by using microsurgical techniques. The parameters of physical fitness and myocardial blood flow were found to be substantially increased in the early periods of postoperation (10-18 days later), less increased at months 2-4, and then unchanged within the year. Thus, it is suggested that cardiovascular performance becomes stable 2-4 months after a successful operation. In this connection, the time the patients with coronary heart disease can resume work after the operation should be revised.

[Transplantation of the heart-lung complex (the first clinical experience)]. / Transplantatsiia kompleksa serdtse-legkie(pervyi klinicheskii opyt).

The article deals with experience in the first transplantation of a heart-lung complex in the USSR. The recipient was a 34-year-old male with dilation cardiomyopathy. It was decided to perform the transplantation because the terminal stage of cardiac failure and secondary pulmonary hypertension developed (cardiac index 1.3 l/m, pressure in pulmonary artery 80/50 mm Hg, resistance of pulmonary vessels 10.4 units after Wood). The heart and lung were transplanted from a 19-year-old male who died from a craniocerebral injury. Cyclosporine, metipred , imuran, dopamine in small doses, cardiotonics, and antibiotics were given in the postoperative period; the patient was kept on artificial respiration for 48 hours. For up to 10 days the patient's condition was relatively stable and his consciousness was clear. Bilateral pneumonia developed, however, from which he died on the 12th postoperative day. The article discusses organizational problems and some questions of immunosuppressive therapy, immunological monitoring, and the management of patients after transplantation of a heart-lung complex.

[Early prognosis of work capacity in patients with ischemic heart disease after direct myocardial revascularization]. / Rannii prognoz trudosposobnosti u bol'nykh ishemicheskoi bolezn'iu serdtsa posle operatsii priamoi revaskuliarizatsii miokarda.

The study was designed to estimate the clinical status and exercise tolerance in 25 patients in the preoperative and early postoperative periods, as well as at weeks 6-8 of direct myocardial revascularization performed by applying microsurgical techniques. The clinical status improved in all the patients. Their exercise tolerance was increased by 67 and 106% 2-3 and 6-8 weeks after the surgery, respectively. Thus, with uncomplicated coronary artery reconstruction, the patients can perform graded physical exercise in the early postoperative period, which provides evidence for reduction of a patient's stay in hospital.

[Indicators of central hemodynamics in patients with disorders of cardiac rhythm and conductivity and nonspecific ECG changes without organic myocardial lesions]. / Pokazateli tsentral'noi gemodinamiki u bol'nykh s narusheniiami ritma i provodimosti serdtsa, nespetsificneskimi izmeneniiami EKG bez organicneskogo porazheniia miokarda.

Pulmonary arterial diastolic pressure (PADP) and cardiac index (CI) were measured by thermodilution at rest and during sitting bicycle ergometry in 95 patients at risk for cardiomyopathy in the future. Normal parameters were recorded in 85 patients: CI increased at least 2.5-fold, and PADP was within 16 mmHg at the peak of exercise. Ten patients showed an abnormal rise of PADP up to 29.0 +/- +/- 1.2 mmHg in the presence of an adequate CI increment. This may be an early manifestation of myocardial contractility disorders.