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Biomedical subjects

V V Korolev

Publications and source records attributed to V V Korolev.

At least 19 recordsLinked to original sources
PubMed2000

Processes of luminescence quenching in study of molecular oxygen diffusion in glassy matrices.

The methods have been developed for studying oxygen mobility by donor quenching in solutions with uniform concentration and in geminate pairs in a solid phase. It is shown that the kinetics of luminescence variations with time is described by a diffusion model. Oxygen mobility has been studied at low temperatures (77 K) in hard polymer matrices. squalane. glasses of low-molecular hydrocarbons and alcohols. The methods can be used to measure very low oxygen mobility with a diffusion coefficient of about 10(-23) cm2 s(-1).

Diffusion↗
PubMed1997

Cyclic AMP and sympathetic neuronal programmed cell death.

The survival and proper functioning of sympathetic neurons are dependent on nerve growth factor (NGF). When immature sympathetic neurons are deprived of NGF, they undergo an 'active' dying process usually termed 'programmed cell death' or 'apoptosis'. This trophic factor dependence is age-related such that the cells become less dependent on NGF as they mature. Removal of NGF in immature cultures, which triggered the process of programmed cell death, resulted in a significant decrease of intracellular cAMP levels. In contrast, when these cells matured in culture and became relatively NGF independent, NGF withdrawal did not lead to a drop of cAMP levels. Pituitary adenylate cyclase-activating polypeptide (PACAP), a naturally occurring bioactive peptide structurally similar to VIP, could increase cAMP levels in these sympathetic neurons, and delay neuronal cell death resulting from NGF deprivation. These results suggest that PACAP may serve as a neurotrophic factor in sympathetic neurons.

Animals↗
PubMed1997

Neurotoxicity of tunicamycin on cultured cerebellar granule cells.

Tunicamycin (TM) is known to cause severe neurological diseases in the central nervous system of animals. Cultured cerebellar granule cells were used to investigate the direct cytotoxicity of this agent on cerebellar neurons. Results indicate that TM is a potent inhibitor of glycosylation and protein synthesis. This agent killed granule cells in a dose- and time-dependent manner. TM treatment of these neurons lead to atrophic cell bodies and condensed nuclei. This TM-induced cell death could be prevented by cycloheximide and aurintricarboxylic acid. In contrast, TM had no apparent toxicity toward nerve growth factor-differentiated PC12 cells under similar conditions. These results suggest that TM kills cerebellar granule cells in a manner similar to programmed cell death.

Animals↗
PubMed1996

Cyclic AMP and pituitary adenylate cyclase-activating polypeptide (PACAP) prevent programmed cell death of cultured rat cerebellar granule cells.

Cultured cerebellar granule cells undergo programmed cell death when they are deprived of depolarizing KCl. Results from this study indicate that the cAMP analog cyclic 8-(4-chlorophenylthio) adenosine-3'5'-monophosphate (CPT-cAMP) can prevent the cell death in a dose-dependent manner, with the maximal effect seen at 500 microM. Approximately 70% of cells can be saved with this concentration of CPT-cAMP for at least 6 days. Pituitary adenylate cyclase-activating polypeptide (PACAP) increased the intracellular cAMP levels of these cells in a time- and dose-dependent manner. This agent can prevent the decrease of cAMP and cell death induced by KCl withdrawal. These results suggest that PACAP could function as a neurotrophic factor for cerebellar granule cells in vivo.

Animals↗
PubMed1996

Specific toxicity of tunicamycin in induction of programmed cell death of sympathetic neurons.

Tunicamycin belongs to a group of antibiotics which can cause severe a nd often fatal neurological malfunction in animals, commonly known as "annual ryegrass toxicity." At the cellular level, tunicamycin is a potent glycosylation inhibitor which is often used to elucidate the importance of glycosylation in protein functions. Earlier reports suggested that tunicamycin was able to interfere with the binding of nerve growth factor to its receptors. In this report, we showed that tunicamycin was able to kill sympathetic neurons in cultures. The mechanism of cell death was observed to be similar to that of "programmed cell death" in sympathetic neurons induced by nerve growth factor deprivation. Such tunicamycin-induced cell death could be prevented by the protein synthesis inhibitor cycloheximide, which was known to prevent the programmed cell death in sympathetic neurons. These results demonstrated that, in addition to the proven CNS neurotoxicity in animals, tunicamycin causes programmed cell death in peripheral (sympathetic) neurons.

Animals↗
PubMed1995

[Etiology of hypertensive states in workers engaged in expedition shifted-duty brigades].

The state of peripheral and central hemodynamics was examined in 603 workers engaged into shifted duty expeditions in West Siberia, considering the length of service in the shifted duty cycle. The examination revealed high occurrence of cardiovascular diseases with prevalent hypertension. Rheographic findings proved that in 5 years of the shifted duty work high blood pressure develops with increased peripheral vascular tone (especially in brain) and enhanced contractility of left ventricle. Important role in the high blood pressure formation is played by changes of hemodynamics in first days after the duty shift.

Adult↗
PubMed1992

[The efficacy of polychemotherapy with cisplatin, methotrexate and 5-fluorouracil in inoperable forms of squamous cell cancer of the head and neck area].

The results of treatment of 19 cases of inoperable squamous cell tumors of the head and neck are discussed. The treatment schedule used three drugs: 100 mg/m2 cisplatin at day 1, 25 mg/m2 methotrexate, intravenously, at day 4, and a total of 1000 mg/m2 5-fluorouracil, at days 4-8 of treatment, by continuous 120 hour-long infusion. Effect was observed in 15 patients. The treatment was effective in 47.4% (complete regression--in 1 case, morphologically confirmed and partial regression--in 8 cases), stabilization--in 26.3 (5 patients) and further progression--in 26.3% (5 patients). Among the untoward side-effects were nausea, vomiting, anorexia, stomatitis and diarrhea. The toxicity proved tolerable.

Adult↗
PubMed1991

[The adequacy and safety of low epidural anesthesia in urological operations on patients with concomitant ischemic heart disease].

An electrocardiographic evaluation of the functional state of the myocardium in patients operated upon for urological diseases under conditions of low epidural anesthesia has shown that in the absence of a cardiovascular pathology the method of anesthesia fails to exert a substantial influence on the circulation homeokinesis and functional state of the myocardium. The following use of the low epidural anesthesia in 105 patients with a coexistent ischemic heart disease during urological operative interventions results in two times less amount of cardiovascular complications, lethality and duration of the postoperative period.

Adult↗
PubMed1990

[The dynamics of the kallikrein-kinin system indices in patients with eczema vera during treatment by the laser photophoresis method with ortofen].

A drastic increase (by 30.6 times) vs. the norm) of kallikrein activity was revealed in 70 patients with true eczema during exacerbation; blood plasma amidase activity was elevated 4.4-fold, serum alpha 2 macroglobulin antiprotease activity 1.4-fold. Laser photophoresis combined with application of a new Soviet nonsteroid anti-inflammatory agent orthofen reduced the parameters of the kallikrein-kinin system, and a tendency to their normalization could be observed.

Adult↗
PubMed1983

[Problem of defining psychopathies and so-called preclinical states in borderline psychiatry].

The structure of the personality of mentally deficient law violators of sound mind can be differentiated into two types of aberrations, namely pathological (clinical disturbances) and nonpathological (social and psychologic deformations). These properties in different combinations were detected in all law violators examined. The role of these deviations in the genesis of law violation is discussed. Differential assessment of clinical, social and psychological phenomena allows a more clear-cut differentiation of psychopathic, psychopathlike and some preclinical conditions and also determination of their probable time-course.

Antisocial Personality Disorder↗
PubMed1982

[Ultrastructural bases of heart failure in the early period of the prolonged crush syndrome].

Histological, electron microscopic, and physiological studies on the myocardium of rats and dogs in severe forms of compression syndrome (6-9 hours of compression and 2-4-7 hours after decompression) revealed three groups of morphological changes underlying cardiac insufficiency: (1) predominantly microcirculatory disorders with mild changes in cardiomyocytes detectable in bradycardia. Under these conditions the development of cardiac weakness may be based on both calcium overloading and reflectory weakening of the heart activity; (2) combination of microcirculatory disorders with marked hypoxic damage of the cardiomyocytes structure detectable under conditions of tachycardia may be an independent cause of the cardiac muscle weakness; (3) changes in the structures of cardiomyocytes responsible for nervous impulses conduction: sarcolemma and its derivatives. Under this condition, the probable cause of cardiac disorders may be electrolyte imbalance accompanying postcompression toxemia.

Animals↗
PubMed1981

[Morphology of the capillaries and muscle fibers in endarteritis obliterans].

The ultrastructure of blood capillaries and muscle fibers was examined in the I, II, III, and IV stages of obliterating endarteritis (OE) of the lower extremities. A number of morphological parameters were analysed quantitatively. The pathogenetic importance of changes in the fine structure of capillaries and muscle fibers for each stage of the disease was demonstrated. Each stage of OE is characterized by definite morphological features of the structure of blood capillaries and muscle fibers which permit to use these data clinically for biopsy diagnosis of different OE stages.

Adult↗
PubMed1980

[Liver regeneration characteristics in young rats in allyl alcohol lesion of the periportal areas].

The authors analyzed ultrastructural changes in hepatocytes of weanling rats, induced by allyl alcohol (0.03 ml/kg). The most severe lesions developed in mitochondria of the periportal field of liver lobules during the first 24 hours following alcohol administration. Early signs of the regeneration were also seen in the periportal field 24 hours after exposure. Three types of dark hepatocytes were distinguished: (1) polygonal cells with the dilated endoplasmic reticulum, increased size and number of mitochodria; (2) stellate cells with the remarkably increased rough endoplasmic reticulum showing free ribosomes and a lot of large mitochondria; (3) cells consisting of irregularly arranged rough endoplasmic reticulum and a great number of small mitochondria. Large hepatocytes containing an insignificant number of organellas were seen in the later stages of the regeneration. The data obtained warranted a suggestion that the cells described represent different phases of hepatocytic regeneration.

Alcohols↗