Phosphine modification of proline-glycine-proline tripeptide and study of its neuroprotective properties.

BACKGROUND: Treatment of neurodegenerative diseases, such as Parkinson's disease, Huntington's chorea, Alzheimer's disease, is one of the priority directions in modern medicine. Thus, search and production of new physiologically active substances for the treatment of neurodegenerative disorders is one of the most important tasks for organic chemistry. The approach based on the replacement of a peptide bond in a peptide molecule with a structural isostere, non-hydrolyzable methylene phosphoryl fragment makes it possible to increase the metabolic stability of peptide molecules to the destructive action of peptidases. METHODS: This work is devoted to the approbation of a new synthetic approach to the production of physiologically active substances in a series of peptide-type compounds with activity by replacing the peptide bond with isosteric methylene-phosphoryl fragment with the preservation of the original amino acid sequence. RESULTS: A phosphine analog of the known physiologically active tripeptide proline-glycine-proline was obtained, cytotoxicity and neuroprotective properties of the initial tripeptide and its phosphine analog were studied. CONCLUSION: Preliminary biological tests have shown that the obtained phosphine analog of the proline-glycine-proline tripeptide is involved in modulating the formation of sediments in the cellular system of proteinopathy, which may indicate their potential antiaggregatory properties.

Parameterization of volume scattering function of coastal waters based on the statistical approach.

A parameterization of the volume scattering function (VSF) specific to coastal waters is proposed. We have found that the standard VSF parameterizations proposed by Fournier-Forand and Petzold do not fit our measurements obtained with a high angular resolution VSF-meter for water samples taken in the Black Sea coastal zone. We propose modeling VSF as a linear function of scattering, backscattering and particulate absorption. The statistical techniques employed allow us to retrieve the variability of VSF and to demonstrate the significance of the estimates obtained. The results of independent validation and the comparison with other commonly used parameterizations are provided.

Gain of electron orbital angular momentum in a direct laser acceleration process.

Three-dimensional "particle in cell" simulations show that a quasistatic magnetic field can be generated in a plasma irradiated by a linearly polarized Laguerre-Gauss beam with a nonzero orbital angular momentum (OAM). Perturbative analysis of the electron dynamics in the low intensity limit and detailed numerical analysis predict a laser to electrons OAM transfer. Plasma electrons gain angular velocity thanks to the dephasing process induced by the combined action of the ponderomotive force and the laser induced-radial oscillation. Similar to the "direct laser acceleration," where Gaussian laser beams transmit part of its axial momentum to electrons, Laguerre-Gaussian beams transfer a part of their orbital angular momentum to electrons through the dephasing process.

[Nitric oxide and electrogenic metals (Ca, Na, K) in epidermal cells].

Using atomic emission spectrometry and EPR analysis metal-ligand homeostasis (MLH) has been studied in epidermal cells of 954 liquidators of the Chernobyl accident and 947 healthy individuals. A possible association of the redox status with the quantitative changes in the MLH, which could be used as discriminators of oxidative/nitrosative stress, attracts special interest. Characteristic features of oxidative stress mainly related to electrogenic metals (Ca, K, Na), were found not only among the liquidators examined, but also in some healthy individuals (18.1%); this suggests the presence of oxidative/nitrosative stress of non-radiation origin. Correlation between intracellular production of nitric oxide (NO) with quantitative changes in the electrogenic metals may indicate the possible involvement of NO in the generation of an electric potential of the cell.

[Effects of ultraviolet irradiation on structural and functional condition of T- and B-lymphocytes of human blood]. / Vliianie ul'trafioletovogo izlucheniia na strukturno-funktsional'noe sostoianie T- i B-limfotsitov krovi cheloveka.

The influence of ultraviolet (UV) radiation on structural and functional condition of membranes T- and B-lymphocytes of human blood is investigated. It is shown, that intergral flow of UV-light (240-390 nm) in doses 151-1359 J/m2 leads to the increase of the expression of some HLA-antigen (DR1, DR2, DR5, DR7) and Fc-receptors on membranes of B-lymphocytes. The level of HLA-antigen was increased by 20-500% from the initial state after exposure to different doses. The growth of the expression of Fc-receprots was registered in 80% of the donors in the range from 20 up to 540%. The minimum dose of UV-light (151 J/m2) caused the maximum effect. The reduction of the level of Fc-receptors by 10-90% relatively to the native condition was registered for T-cells in 80% of the donors. Groups of the donors were revealed, T-lymphocytes of which differed by the sensitivity to UV-radiation. The effect of "strengthening--weakening", resulting to the reduction of the initially high parameters and to increase in the initially low ones was found.

[Comparison of flow-volume curve parameters in patients with respiratory sarcoidosis and chronic non-specific pulmonary diseases]. / Sopostavlenie parametrov krivoi potok-ob''em u bol'nykh sarkoidozom organov dykhaniia i KHNZL.

62 patients with respiratory sarcoidosis (RS) and 50 patients with chronic nonspecific pulmonary diseases (CNSPD) inhaled 1 ml (250 mg ipratronium bromide and 500 mcg phenoterol hydrobromide) berodual by means of nebulizer. 68% of the examinees responded with obstruction of the distal part of the respiratory tree. RS causes partially reversible defects in permeability, primarily at the level of small bronchi. Berodual-induced changes in the curve flow-volume in RS differed from those in CNSPD patients by the absence of a rise in the exhalation power. Lofgren's syndrome deteriorated reversibility of bronchial permeability defects in RS patients. Smoking effects on bronchial permeability and reversibility of relevant defects in RS patients were insignificant. Pathogenesis of reversible obstruction in sarcoidosis demands further studies.

[Repeated surgeries on the thyroid gland in nodular euthyroid goiter]. / Povtornye operatsii na shchitovidnoi zheleze pri uzlovom éutireoidnom zobe.

Medical histories of 214 patients hospitalized with diagnosis "recurrent nodular goiter" were studied retrospectively. Complex clinical, laboratory and instrumental examination was carried out in all the patients. Comparative analysis demonstrated that in the structure of recurrent goiter nodular colloid form dominated (84.1%), only in 42.1% cases repeated surgeries were indicated. Other patients (15.9%) were the ones underwent surgery for other thyroid diseases (hypertrophied form of autoimmune thyroiditis, follicular adenoma, thyroid cysts, thyroid cancer). Inadequate surgery and prophylactic therapy with iodine drugs were the main causes of recurrent goiter. Adequate iodine prophylaxis (potassium iodide 100-200 mg per day), complex examination of patients, correct indications for primary surgery and adequate surgical volume, valuable postoperative therapy (iodine drug, LT-4 if it is necessary) permit to reduce the risk of recurrent nodular (multiple-nodular, diffuse-nodular) goiter. Ways of researches for improvement of diagnosis, prophylaxis and treatment results of "recurrence nodular goiter" are projected.

[Comparative evaluation of effects of various bronchodilators in sarcoidosis]. / Sravnitel'naia otsenka deistviia razlichnykh bronkholitikov pri sarkoidoze.

The investigation was undertaken to compare three bronchodilators on patients with respiratory sarcoidosis. Ninety patients (66 females and 24 males) with intrathoracic sarcoidosis were examined. X-ray stages I, II, III, and IV were seen in 48.9, 46.7, 3.3, and 1.1%, respectively. A flow-volume curve was recorded on a Masterscreen Pnevmo apparatus (Erich Jaeger) before and after inhalations of salbutamol (200 micrograms, a flask), ipratropium bromide (40 micrograms, a flask), and 1 ml of berodual solution through a Boreal nebulizer. The mean baseline values of forced expiration were normal, except for MOS75 (51.0 +/- 1.3% of the normal values). After salbutamol, the increment of MOS75 was higher than that after ipratropium (20.7 +/- 3.1% and 12.3 +/- 2.3%, respectively, p < 0.05); however, after berodual nebulization, the increase in MOS50 was greater than that after inhalation of ipratropium (17.2 +/- 1.9% versus 10.7 +/- 1.6%, p < 0.05) or salbutamol (10.1 +/- 6%, p < 0.01). The changes in these parameters in smokers and nonsmokers were similar. The one-month or more inhalation of budesonide (benacort) potentiated the bronchodilating action of salbutamol on all the parameters of forced expiration, but failed to affect the effect of ipratropium and berodual. Prednisolone did not affect the effects of bronchodilators. A combination of beta 2 agonist and inhaled steroid may be effective in intrathoracic sarcoidosis with the bronchial obstruction syndrome. The mechanism of varying action of the drugs having different mechanisms of action requires further investigations.

[Expert work during technogenc emergency situations (Report I)]. / Ekspertnaia rabota pri tekhnogennykh chrezvychainykh situatsiiakh (Soobshchenie pervoe).

The authors discuss the organizational principles of the work of expert institution and its subdivisions with reference to technogenic catastrophes accompanied with mass human victims. The problems of interaction of the representatives from different structures and departments taking part in the work at the place of event are considered in terms of forensic medicine. The attention is concentrated on the problems of expert institution readiness to work under conditions of extreme situations depending on the medicotactical characteristics of defeat focus.

[Expert work during technogenic extreme situations (Report II)]. / Ekspertnaia rabota pri tekhnogennykh chrezvychainykh situatsiiakh.

The article is devoted to the organizational principles of work of expert institutions and its subdivisions with reference to technogenic catastrophes with mass victims. The problems of interactions of representatives from different structures and departments made busy with the work at the place of event are discussed in terms of forensic medicine. Special attention is paid to the problems of expert institution readiness for work under conditions of extreme situations depending on the medical-and-tactical characteristics of damage focus.

[The state legal and expert identification aspects of protecting the right of the person for citizens of the Russian Federation]. / Gosudarstvenno-pravovye i ékspertno-identifikatsionnye aspekty okhrany prava lichnosti grazhdan Rossiiskoi Federatsii.

The article deals with the questions concerning the problem of person identification, different extreme situations. This problem is closely connected with ensuring of national security of Russia. The authors give the definition of person's right in contact with constant threat to violate this right. Two categories of person's properties are analysed (material and not material) with the help of which it is possible to establish identity of man and his personality. It is noted that protection of person's rights is carried out in six forms. For the first time the possibilities to create organisational system of person identification in the form of Federal service are discussed that must be legislatively secured. Scientific investigation of this problem allowed the authors to submit concrete proposals concerning the question of organisation of state service for person identification.

Thoracoscopic surgery in the management of mediastinal masses. Indications, complications, limitations.

BACKGROUND: In recent times thoracoscopy has been used for diagnoses and treatment of mediastinal masses. This study is a preliminary review of indications, complications, and limitations in this field of surgery. METHODS: Twenty-eight patients with mediastinal masses were operated in the Clinical Oncological Centre, Kazan. Twenty-two of them had anterior mediastinal growths; six had posterior mediastinal tumors. Thoracoscopy was diagnostic in 14 cases; it was therapeutic in 14 cases. RESULTS: The definite diagnosis was achieved in all patients. In cases of benign lesions the operations were successfully completed thoracoscopically. All patients underwent a postoperative period with low pain and short postoperative time. CONCLUSIONS: Video-assisted thoracoscopy is indicated in cases of mediastinal masses, both for diagnosis and treatment. It has significant advantages compared to normal thoracoscopy and mediastinoscopy.

[Luminescent-microscopic study of soil microorganisms]. / O liuminestsentno-mikroskopicheskom izuchenii pochvennykh mikroorganizmov.

Soil microorganisms can be quantitatively assayed by means of a technique which makes use of staining preparations on slides with acridine orange. When bacterial cells were counted daily in humus-gleisolic soil, their number did not depend on time if the soil was incubated for five days. Mixed soil samples corresponding to the same time of incubation differed reliably in the bacterial number. The paper presents a scheme for determining the necessary number of samples, preparations, and fields of vision when the number of bacteria is being estimated. It is expedient to take 7 samples from a soil mixture, to make 2 preparations out of each sample, and to count bacteria in 5 fields of vision for each preparation.

[Around the Semipalatinsk proving grounds: the radioecological situation and the population radiation doses in Semipalatinsk Province (based on data from the report of the Interdepartmental Commission)]. / Vokrug Semipalatinskogo poligona: radioékologicheskaia obstanovka, dozy oblucheniia naseleniia v Semipalatinskoi oblasti (po materialam otcheta mezhvedomstvennoi komissii).

The paper represents some results of a joint commission, organized by the USSR Ministry of Health by order of the USSR Council of Ministers at public requests. The commission worked in the area neighbouring the proving ground at Semipalatinsk in the period of May-July 1988. A radiological situation there was investigated after underground nuclear testing on July 8, 1989. The results of measurements and archive data were used to estimate doses of radiation exposure of the population in the period of 1949 (nuclear testing on the ground and in the atmosphere) and in the period of underground testing, It was shown that in the period of 1949-1963 approximately 10,000 people received increased doses of external and internal irradiation. A high level of radiation-induced chromosome aberrations was noted among them. The highest effective equivalent doses of external and internal irradiation were received by the residents in the villages of Folon' (1.6 Gy during the first testing in 1949), Karaul (0.37 Gy), Sarzhal (0.20 Gy), Semenovka (0.02 Gy). The annual effective equivalent doses at that period did not exceed 0.0056 Gy (the highest value) for the Semipalatinsk residents. Proceeding from the values of collective doses probable long-term effects (malignant tumors) were assessed. Recommendations and conclusions of the commission are presented.