[Molecular mechanisms of transcription through a nuclesome by RNA polymerase II].

The Pol II-type mechanism is conserved from yeast to human. After initiation of transcription, Pol II can be paused within the early transcribed region of a gene. Then Pol II overcomes the initial nucleosomal barrier, and efficiently proceeds through chromatin. At low- to moderate-level transcription progression of Pol II is characterized by displacement/exchange of only H2A/H2B dimer(s) and hexasome survival, likely mediated through formation of small intranucleosomal DNA loops. This mechanism helps to preserve the "histone" code during transcription. As the transcription rate is increased, the distance between transcribing Pol II complexes becomes shorter, and trailing Pol II complexes may encounter the hexasome formed after previous transcription round, before the H2A/H2B dimer re-binds to the hexasome. In this case an unstable intermediate with a smaller number of DNA-histone contacts is formed, resulting in eviction of the histone hexamer from DNA in vitro; therefore here all core histones are evicted/exchanged in vivo. Various protein factors and histone chaperones are involved in chromatin transcription by Pol II in vivo.

[Three patterns of trypanosomatid cryptogene structural organization].

We sequenced a number of cryptogenes from previously unstudied species of homoxenous trypanosomatids belonging to the different phylogenetic groups and found new examples of editing domain length reduction for A6 and COIII. The comparative analyzes of sequences allows to divide the cryptogenes in three groups (patterns) according to the degree of primary structure conservation and editing domain length variation. We discuss the possible factors which influence the cryptogene's structure and evolutionary behavior. Also we demonstrate alternative editing of rps12 transcript in Wallaceina sp. Wsd.

[Pathomorphology of specific inflammation in silicotuberculosis].

Silicotuberculosis is an independent disease that arising in patients with silicosis from exacerbation of old tuberculous foci in the lung, less frequently in the lymph nodes and other organs. In silicotiberculosis, there are common secondary tuberculosis forms that are located mainly in the lung, which are rarely accompanied by a rapid progression. Characteristic morphological signs of early, nodal and nodular silicosis are observed. Silicotuberculosis is an independent disease that arises in patients from an exacerbation of old tuberculous foci in the lung, less frequently in the lymph nodes and other organs. In silicotuberculosis, there are usually secondary tuberculosis forms that are located mainly in the lung, which are rarely accompanied by a rapid progression. The characteristic morphological signs of early, nodal, and nodular silicosis are observed. Thoracic and abdominal lymph nodes, lymphatic and blood vessels, the bronchi and pulmonary surfactant system were explored. In silicosis, tuberculosis, and silicotuberculosis, silicon levels and spodograms of some visceral organs were studied and trace elements were determined in the lung.

[Diagnosis, treatment and prophylaxis of postoperative recurrent nodular goiter]. / Diagnostika, lechenie i profilaktika posleoperatsionnogo retsidivnogo uzlovogo zoba.

Results of surgical treatment of 81 patients with recurrent goiter and 79 patients with benign nodular forms of goiter are analyzed. Based on clinical data, results of ultrasonic and histological examinations, it was determined that recurrence of goiter does not depend on volume of surgery. It is seen in patients with subclinical forms of postoperative hypothyreosis and in half of cases with lymphoid infiltration of I - IV degree. Dispensary observation and timely prescription of suppressive therapy, if it is necessary, permit to reduce number of goiter recurrences from 8.2 to 2.5%.

[Clinical and morphological comparisons in pulmonary tuberculosis in workers from pneumoconiosis-risk industries]. / Kliniko-morfologicheskie sopostavleniia pri tuberkuleze legkikh u rabochikh koniozoopasnykh proizvodstv.

The relationship between the efficiency of treatment and the nature of morphological changes in the lung was studied in 125 patients with pulmonary tuberculosis without X-ray signs of pneumoconiosis who worked at coniosis-risk enterprises (CRR). Despite adequate specific and pathogenetic therapy, tuberculomas formed and decay cavities preserved in the patients, in this connection they had surgical treatment. Three types of morphological changes were identified. Quartz-containing industrial dust was found to exert an adverse potentiating effect on the course of tuberculosis in most CRE patients: increases in the delimiting a specific process of respiratory disorders and postoperative complications. These specific features should be borne in mind in drawing up a treatment protocol for patients working exposed to industrial dust.

[Clinical and morphological characteristics of migrating erythema in patients with Ixodes tick-borne Lyme disease]. / Kliniko-morfologicheskie osobennosti proiavlenii migriruiushchei éritemy u bol'nykh iksodovym kleshchevym borreliozom.

Patients with erythematous Ixodes tick-borne relapsing fever were examined and their skin biopsy specimens were morphologically studied to reveal clinical, immunological and morphological features of erythematous Ixodes tick-borne relapsing fever. Two types of development of erythema migrans were identified. These include 1) a typical type that appears as an area of homogenous hyperemia or that of annular shape and 2) an atypical one that presents as minor vesicles. There were elevated serum immunoglobulins A levels at the height of the disease. Morphologically, at the early stage of the disease, the center of erythema shows disturbances characterized by epidermal dystrophic processes, koilocytosis, subhorny and epidermal vesicles. The dermis displays solid perivascular lymphocytic infiltrates admixed with fibroblasts, fibrocytes, macrophages, plasmocytes, eosinophils, degranulated labrocytes. The interstitium exhibits scanty infiltrates. These changes are less pronounced at the periphery. Electron microscopy shows the structures morphologically similar to those of Borrelia. The late stage (days 15-23) of the disease is marked by insignificant dystrophy and perivascular fibrosis. There were no interstitial infiltrates. By and large, the pattern of clinical and immunological manifestations in patients with erythema migrans correlates with dermal morphological changes.

[The status of the external respiratory function in patients with tuberculosis of the lungs and pre-roentgenologic pneumoconiosis changes]. / Sostoianie funktsii vneshnego dykhaniia u bol'nykh tuberkulezom legkikhs dorentgenologicheskimi pnevmokonioticheskimi izmeneniiami.

The ventilation function was studied in 103 pulmonary tuberculosis patients of pneumoconiosis-risk occupations in the absence of pneumoconiosis and in 51 patients who were not exposed to dust. Patients of "dust" occupations were found to have a decrease in the parameters of external respiration and bronchoscopic findings more often showed chronic bronchitis. The initial signs of pneumoconiosis were revealed in the histological examination of surgically removed lung segments in 83.4% of the patients.