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V Vasilev

Publications and source records attributed to V Vasilev.

At least 19 recordsLinked to original sources
PubMed2003

Age-related differences in MK-801- and amphetamine-induced locomotor and stereotypic activities of rats.

Changes in locomotor and stereotypic activities induced by an i.p. injection of either (+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)-cycloheptan-5,10-imine maleate (dizocilpine or MK-801; 0.3 mg/kg) or D-amphetamine sulfate (AMPH; 1.5 mg/kg) were studied in male Mill Hill hooded rats of different age. The following age groups of animals were considered: 28-30 postnatal day (PND)-old rats (peripubertal), 48-50 PND-old (pubertal), 3-month-old (adults), 12-month-old (middle-aged) and 24-month-old (aged). The motor response was measured by an automated animal activity measuring system. The obtained results showed that: (1) in contrast to AMPH, MK-801 induced more pronounced increases of both locomotor and stereotypic activities in peripubertal and pubertal than in adult and aged rats; (2) AMPH induced the same locomotor and stereotypic activity increase in pubertal, adult and middle-aged rats; (3) both AMPH and MK-801 led to a senescence-related decrease of motor activity. These data suggest that the balance of the glutamatergic and dopaminergic systems changes during aging. Such a change is important in understanding schizophrenia and the motor system decline observed in the later stages of life.

Aging↗
PubMed1995

[The use of expanders in soft-tissue plastic-reconstructive surgery].

Thirty-six years ago, Neumann was the first to practically implement skin expansion by means of subcutaneous rubber balloon inflation. After discovery of the silicone elastomer (1970), Padovan initiated the wide application of expanders in practice. Ever since then, the latter have conclusively demonstrated their contribution to plastic and reconstructive surgery in handling skin and soft-tissue defects in all parts of the body. The preparation and utilization of expanders are closely linked to the goals pursued, and evolve through several stages: 1) selection of the size and number of expanders, 2) choice of expander consistent with the valve type, 3) choice of the site and orientation of the incision for subcutaneous puch formation for the expander, 4) depth of expander insertion, 5) size of the punch for expander, valve and tube. After insertion of the silicone balloon (expander) subcutaneously, its inflation with serum is begun. Recently, early (for 24 hours) and quick (for 7-10 days) inflation of the expander is resorted to. The tolerance of both tissues involved, and patient is the basic criterion for practical implementation of the technique described. As any operative intervention and procedure, the use of expanders is associated with a number of complications. In general they are divided in: 1. minor--where discontinuation of the expansion process is unnecessary, but it is prolonged until the planned extension is attained, and 2. major--necessitating complete discontinuation of the process of expansion and performing additional procedures.

Humans↗
PubMed1992

Ultrastructural changes in the synovial membrane in experimentally-induced osteoarthritis of rabbit knee joint.

Rabbit knee joint osteoarthritis was induced by intraarticular injections of a 10% sterile NaCl solution. Within 30 days the synovial membrane had undergone hyperplasia resulting in activated synovial fibroblasts. Transitional forms of synoviocytes as well as activated synovial macrophages were a very common finding. At 60 days a thickening of the synovial intima was perceptible. Most of the synoviocytes were of the fibroblast type. Transitional cell forms abounded. An increase in collagen fibres and capillaries of the fenestrated type occurred in the intercellular spaces. In the deep layer collagen bundles had formed between which activated fibroblasts and macrophages were noticed. The described changes point to an active participation of the synovial membrane in the destruction of articular cartilage in osteoarthritis.

Animals↗
PubMed1990

Changes in the distribution of proteinpolysaccharide complexes within the articular cartilage in experimental osteoarthrosis.

The quantity and type of proteinpolysaccharide complexes in the matrix determine up to a great extent the mechanical properties of articular cartilage. It is the purpose of this study to evaluate the changes in the mentioned matrix components against the background of experimentally induced osteoarthrosis. As shown by electron microscopic and morphometric studies, the changes in the superficial layer are promptly occurring and clearcut, whereas those in the deep layers are recorded in late observation terms only. A reduction of proteoglycan quantity is noted with a simultaneous differentiation of their fine structure in the various stages of osteoarthrosis development. Initially the alteration in the cell organization of chondroblasts is associated with occurrence of differences in proteoglycan content, and subsequently--in the collagen structures of the matrix too.

Animals↗
PubMed1990

[Changes in the articular and growth cartilage of young rats after the intra-articular injection of hydrocortisone].

Changes in the cells and matrix of the joint cartilage (JC) and growing cartilage (GC) of tibias of young rats after five-fold administration of hydrocortisone in a dose of 10 mg/kg of body weight were studied by routine histological and histochemical methods. Fissures occurred in JC, but its superficial layer thickened. The cells of this layer acquired the form of fibroblasts, but the reaction for proteoglycans gradually weakened and became negative. The cells in the proliferative and hypertrophic zones were involved mainly in GC. The amount of granulated endoplasmic reticulum diminished. The number of myelin-like figures was increased. Pilings of thick collagenous fibers occurred in the matrix.

Animals↗
PubMed1988

A study of the two-way transport of horseradish peroxidase across the visceral pleura.

The authors report on a study of the transpleural transport of horseradish peroxidase after intrapleural and intracardiac application. Following intrapleural introduction, a retention of the marker on the apical membrane of mesothelial cells was observed, with subsequent transcellular transfer after incorporation into microvesicles. Following intracardiac injection, the marker moved out of the pulmonary capillaries across the endothelial vesicles and progressed to the pleural cavity across the intercellular spaces and mesothelial vesicles. With either route of injection, reaction product was noted in the basal lamina of the mesothelium, elastic membrane, alveolar macrophages and pneumocytes type II.

Animals↗
PubMed1987

Clinical-morphological and electron-microscopic studies of the growth plate in solitary bone cysts.

The occasional humeral growth retardation or premature closure of the growth plate medially, documented among more than 120 solitary bone cysts reviewed, was reason to undertake a thorough study of the growth plate in the area of the cyst. The findings in the hyaline zone disclose a considerable number of vessels and slits of the cartilage that are broadened toward the proliferative and hypertrophic zones. In some places they communicate with the vessels or are lined with endothelium. Ultrastructurally, changes of a destructive nature are disclosed, involving the growth plate zone and corresponding to the most active metabolic processes. In the altered chondrocytes substantial increases in glycogen granules and lipid droplets are observed, as well as reduction of the cellular organelles. In rather severely affected cells changes in the nuclei, lysosomal structures, and myelin-like lamellar bodies are established. The disappearance of cellular organelles and the fragmentation of cytoplasm are interpreted as a final phase of the above-listed changes. In conclusion, the cyst is considered a probable primary cause of the changes described.

Adolescent↗
PubMed1987

[Lyophilization of live CA-80 vaccine against coli enteritis in pigs].

A live vaccine against coli enteritis in pigs, CA-80, with a protection medium of 5 per cent hemodex, was successfully freeze-dried in ampoules or vials at the rate of 5 to 10 vaccinal doses each, the titer ranging from 10(9) to 10(10) live bacteria per cu. cm, of a 12-month shelf-life period. The vaccine was found to be innocuous for pigs, and was intended for active immunoprophylaxis on both infected and menaced farms and complexes, applying it to sows in the last third of the gestation period.

Animals↗
PubMed1987

[Clinical and hemodynamic characteristics of patients with an aortic valve defect before the implanting of an aortic valve prosthesis].

The clinical and hemodynamic characteristics, perioperative and early postoperative results were studied in 38 patients with aortic valve prosthesis in order to determine the indications for surgical treatment in isolated aortic valvular disease. The basic factors determining the need for surgical treatment are: severity of the aortic lesion--stenosis and/or incompetence, degree of the harmful action of the aortic valvular disease on the left ventricle (clinical data for left ventricular failure; hypertrophy and dilatation--telediastolic volume greater than 300 ml/m2, telesystolic volume greater than or equal to 50 ml/m2; myocardial lesion; hemodynamic data for left ventricular dysfunction) and functional class of the patients. Most of the patients were with severe aortic incompetence and/or aortic stenosis and considerably diminished functional capacity. Only few patients had a low degree valvular lesion but they also showed some of the signs of its harmful action on the left ventricle.

Adult↗
PubMed1985

Cilia in rat articular chondrocytes.

The cilia ultrastructural characteristics of chondrocytes from articular cartilage during its prenatal development were studied. It was established that these structures are not rare in electron microscopic observation of cartilage. They appear in the early stages of differentiation of the mesenchymal cells into chondroblasts. Ultrastructurally they show no differences during all periods of development. In some of the tangential layer cells of the newly formed articular cartilage were discover elements of more than one cillium in the same cell. It was also established that these structures project from parts of the cell presenting well developed Golgy complex.

Animals↗