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The use of stem cell technologies in retinal defect reparation therapy has produced beneficial results. Nowadays, numerous protocols exist which provide a neural differentiation of the stem cells transplanted into the retina. However, questions concerning the functional replacement of the missing retinal neurons by transplanted cells thus far remain unanswered. The organotypic culture protocol was used in this study in order to prove the possibility of transdifferentiation of bone marrow stromal cells (MMSCs) and neural stem/progenitor cells (NSPCs) from EGFP-positive mice and the functional integration of these cells. This technique enables a detailed characterization of cell behavior post-transplantation. Using atomic force microscopy, we reliably demonstrated the difference (p < 0.01) between the thickness of the outgrowths formed by glial and endothelial retina cells and the thickness of neurites and neuro-like transplanted MMSC outgrowths. MMSCs are also shown to form synapses up to 2.5 ± 0.06 µm in diameter on day 4 after the transplantation. Following electrical stimulation (20V, 0.5Hz, 200ms), clear depolarization of retinal neurons and their outgrowths is detected. It is shown that some of these GFP+ MMSCs, which changed their morphology after the transplantation in retinal explants to neuro-like MMSCs, are capable of depolarizing after exogenous stimulation.

Practical advantages of using femtosecond laser pulses for manipulations in cell surgery were demonstrated. The use of femtosecond laser pulses enables precision punching of the zona pellucida of the embryo without damaging its cells. With the help of femtosecond laser tweezers/scalpel, auxillary laser hatching was performed and a technique of optical biopsy of mammalian embryo was developed, which enabled non-contact sampling of embryonic material for preimplantation diagnostics. Our findings suggest that about 90% embryos retained the ability to develop at least to the blastula stage after this manipulation.

A modified method of proteome comparative analysis based on preliminary removal of cell structural proteins by extraction using salt buffer and subsequent separation of extracts by two-dimensional gel electrophoresis was developed. Identification of differentially expressed proteins by mass spectrometry has revealed three proteins with noticeably increased level of synthesis in most samples of papillary thyroid tumors compared to normal tissues. An increase in ubiquitin content was found for the first time. Oncomarker search efficiencies by two-dimensional gel electrophoresis and bioinformatic search were compared.

The article presents an original technique of voice restoration in patients who have undergone laryngopharyngectomy with resection of esophageal cervical part; analyses mechanism of phonation. Four cases of prosthetic reconstruction are reported. The necessity and feasibility of voice rehabilitation in patients with this severe condition are validated.

Interleukin-2 (IL-2) production followed by with aftereffect of the immunosuppressive agent hydrocortisone and mitogen-induced proliferation of T lymphocytes were studied in the presence of artificial beta-carotene. Treatment of CBA mice with the drug was performed within various periods. beta-Carotene was found to elevate IL-2 secretion and the effect was both time- and dose-dependent. The drug removed immunosuppression developed after intraperitoneal administration of hydrocortisone. At the same time, beta-carotene stimulated mitogen-induced proliferation of T cells, which was dose-dependent.

The analysis of the data on 744 patients with thyroid tumors showed inadequate examination to be the main cause of untimely diagnosis of cancer of the organ. Cytologic examination of tumor punctate proved most effective for diagnosis since it confirmed cancer in 92.3% of cases. Adequate examination and extrafascial surgical procedure with intraoperative contrasting of the thyroid assured five-year survival rate of 95.9% and a decrease in the risk of injury to n. recurrens by 23%.

Alterations in lipid composition were studied by means of micro-thin-layer chromatography technique in rat myocardium during postmortal autolysis. Lipids of rat heart were stable enough at early periods of the autolysis. At the same time, the most labile fraction included phospholipids, polyglycerophosphatides and lecithins. The more stable fraction contained free cholesterol and neutral lipids. The main pathways of lipid degradation within the first 24 hrs of autolysis operated via hydrolysis of phospholipids, neutral lipids as well as via reactions of transacetylation and biotransformation (methylation etc).

The paper deals with a 10-year experience (1971-1980) of treating tumors of head and neck at the Institute. Different aspects of early diagnosis of thyroid carcinoma, its adequate therapy and organisational measures required for its prevention are discussed on the basis of 1,304 case histories of thyroid cancer. Up-to-date methods of early diagnosis of thyroid cancer (diagnostic puncture and thyroidlymphography), which can be integrated with general medical practice, are recommended. Causes of errors leading to failure to remove the whole malignancy are discussed. Recommendations how to obviate this difficulty are given and measures aimed at ensuring a 5-year survival in 98% of cases and adapted to different groups of cancer patients are suggested.

Some aspects of the lipids metabolism in the blood serum of students differing in their age, working and learning experience prior to entering the institute, followed up throughout the examination period, are presented. Subject to determination was concentration of total lipids and their principal fractions: phospholipids, free and estherified cholesterol, free fatty acids and triglycerides, accomplished by means of micro-thin layer chromatography. Investigations were conducted 5 weeks, 1-2 days before examination and 5 weeks thereafter. A study of the lipids metabolism under nervous-emotional stress in dynamics may serve as one of the methodological approaches enabling one to reveal in good time any changes in the lipids metabolism.

A rapid and sensitive microanalysis in blood serum of total lipids and their main fractions (phospholipids, free cholesterol, free fatty acids, triglycerids, esters of cholesterol) by means of micro-thin layer chromatography is described. The quantitative determination of total lipids and their fractions, after elution from the chromatogramms, was carried out by means of degradation with concentrated sulphuric acid and subsequent photometric estimation at 400 nm. The method enabled to determine from 15-20 mcg to 180-200 mcg of total lipids and their fractions. The error of the method did not exceed +/-8.5% for total lipids.

Alterations in content of main classes of lipids and phospholipids were studied in blood serum during autolysis in normal rats and in acute oxygen deficiency. In the control animals the most distinct alterations were found in content of phospholipids, which was decreased down to 1/2 of the initial level within 24 hrs of autolysis with simultaneous increase in concentration of fatty acids within 10 hrs. A decrease in content of free cholesterol together with an increase in concentration of its esters were observed in hypoxic animals within 24 hrs of autolysis. During autolysis concentration of phosphatidylcholines was decreased both in control and hypoxic animals. At the same time, an increase in lysophosphatides within 4 hr of autolysis and a decrease in concentration of phosphatidic acids within 24 hrs were found in the control group. In animals with hypoxia phosphatidic acids were only slightly increased and polyglycerophosphatides were found during subsequent periods of autolysis.

Changes in the total lipid spectrum of serum of rats exposed to acute hypoxia were examined. Quantitative measurements of lipids showed a decrease of total lipids and a redistribution of lipid components in absolute and relative values. A distinct decrease in the quantity of cholesterol ester and a concomitant increase of free cholesterol, an elevation in the relative content of free fatty acids and emergence of diglycerides were noted. The qualitative composition of phospholipids remained unaltered, whereas the absolute amount of glycerophosphates, lysoforms of phosphatids, phosphatid acids and lecithin fraction increased. The changes in the ratio of lipid components are closely connected with the qualitative and quantitative changes in the composition of serum lipoproteins.

Among 338 patients operated upon for "nodes" in the thyroid in 31.4% of cases there was found small cancer (up to 1 cm in diameter), determined microscopically and visually. A clinico-morphological definition of early thyroid cancer is suggested. It is emphasized that for the recognition of early thyroid cancer being successful a complex diagnostic method is essential, which comprises clinical, roentgenological, thyroidolymphographic, radioisotope, cytological and histological studies. The method concerned makes it possible to increase considerably (up to 77.4%) the rate of recognition of early thyroid cancer, while the operations, performed after the extrafascial technic, would provide for an adequate therapy in due course and a favourable prognosis.

By a modified microthin-layer chromatography in the total lipid spectrum of the cardiac muscle of white rats exposed to acute oxygen deficiency in an altitude chamber was investigated. It was found that the content of total lipids, phospholipids, free cholesterol, free fatty acids and triglycerides decreased during acute hypoxia. The exposure induced changes in the amount of glycerophosphatids whose content diminished significantly. The concentration of phosphatidyl serines and phosphatidyl ethanol amines lowered to a lesser extent while that of sphingomyelins increased. Acute oxygen deficiency accelerates the release of inorganic phosphate from the heart, thus, together with other factors, leading to disorders in the heart energetics. These findings indicate an important role of hypoxic hypoxia in the disturbances of lipid metabolism of the myocardium. This needs to be taken into consideration in the diagnostics and treatment of such states.

The results of thyroidlymphography carried out in 122 patients with thyroid cancer and 82 cases of benign tumor were analysed. Reliable thyroidlymphographic criteria of malignancy were established on the basis of a comparison of roentgenomorphologic and statistical findings. The significance of the said criteria for making timely diagnosis of cancer with concomitant adenomatosis and chronic thyroiditis is discussed.