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Hydroxylclinohumite Mg5(SiO4)2(OH,F)2 is a common monoclinic orthosilicate of the humite group, which, on the one hand, is a prototype of promising materials, and, on the other hand, is an important source of information about both the transport and the presence of water in the Earth's mantle, and therefore studying its thermal behavior is of particular interest. In this paper, the mineral is studied by powder X-ray diffraction for the first time in a wide temperature range (–180 ≤ T ≤ 1000°C). The temperature limits for the existence of the phase are established, the principal values of the thermal expansion tensor are calculated, and a structural interpretation of thermal expansion is given. [ABSTRACT FROM AUTHOR]

In the Na2SO4–K2SO4 system, nine phases are known. In this study, for the first time, the values of the thermal expansion coefficients of continuous high-temperature solid solutions crystallizing in the P63/mmc crystal system, low-temperature limited solid solutions based on natroaphthitalite and aphthitalite (P3-m1), and polymorph II Na2SO4 (Pbnm) in the Na2SO4–K2SO4 system are provided. The genetic succession of polymorphs P3m1 and P3-m1 ↔ P63/mmc, which manifested itself in the double sulfates of this system, is revealed. [ABSTRACT FROM AUTHOR]

The thermal expansion of magnesium borate (Mg3B2O6) is studied by the method of X-ray thermodiffraction in the temperature range 25–1100°C. The coefficients of thermal expansion are calculated as follows: αa = 13.0(5), αb = 8.5(5), αc = 8.0(5), αV = 30(1) × 10–6°С−1 at 25°C; and αa = 20.0(5), αb = 13.0(5), αc = 13.0(5), αV = 46(1) × 10–6°С−1 at 1100°С. The direction of the maximal thermal expansion (αa) is perpendicular to the preferred orientation of the BO3 triangles. [ABSTRACT FROM AUTHOR]

Hydroxylclinohumite Mg5(SiO4)2(OH,F)2 is a common monoclinic orthosilicate of the humite group, which, on the one hand, is a prototype of promising materials, and, on the other hand, is an important source of information about both the transport and the presence of water in the Earth's mantle, and therefore studying its thermal behavior is of particular interest. In this paper, the mineral is studied by powder X-ray diffraction for the first time in a wide temperature range (–180 ≤ T ≤ 1000°C). The temperature limits for the existence of the phase are established, the principal values of the thermal expansion tensor are calculated, and a structural interpretation of thermal expansion is given. [ABSTRACT FROM AUTHOR]

Ninety adolescents suffering from tuberculosis with primary drug resistance (PDR) in Mycobacterium tuberculosis (MBT) were followed up. All the patients had active, marked processes, mainly infiltrative tuberculosis in the phase of decay and dissemination. MBT resistance to 3 drugs or more was detected in most patients (62.3%). Multidrug resistance was 32.2%. The course of the disease was chiefly favorable. An exacerbation of the process occurred during therapy in 6.6% of patients. In patients with PDR, abacillation occurred in 100% of cases and the decay cavities closed in 86.6% by the end of the course of therapy. The PDR patients received treatment with both first- and second-line drugs, had surgery, collapsotherapy, laser therapy, and physiotherapeutic treatments, and lidase. Treatment of patients with drug-resistant tuberculosis presents severe difficulties. However, good results can be achieved in most patients, by applying an individual approach to each patient and determining the optimum chemotherapy regimens and pathogenetic treatments.

The long-term results of treatment in adolescents with drug-resistant tuberculosis were studied. Forty-one patients were examined 1.5-5 years after discharge from hospital. Thirty-nine of the 41 patients were found to have good outcomes of the disease without exacerbations and recurrences. A recurrence was detected in 2 (4.9%) patients. Prior tuberculosis did not affect lifestyle and choice of a profession in 36 (87.8%). There were limitations in the choice of a profession in 3 (7.3%) patients (they were students of culinary colleges).

Forty-nine adolescents with active pulmonary tuberculosis were followed up to assess the biological chip test for the detection of rifampicin resistance in Mycobacterium tuberculosis (MBT). Rifampicin resistance (rpo B gene mutation) was detected in 22 (44.9%) patients. Disseminated processes were detected in a larger proportion of the patients with rifampicin resistance than in those with MBT susceptibility (63.6 and 40.7%, respectively (p < 0.05). Comparison of the data on MBT resistance and susceptibility, which had been obtained by bacteriological studies (nutrient medium cultuvations) and the biological chip test, revealed their agreement in 50% of the cases. A response could be showed after 2-3 months in the former case and after 2-3 days in the latter case. With the biological chip test, the resistance of MBT to rifampicin was additionally established in 38.7% of the patients with negative cultivation tests on admission and during therapy. Follow-ups have demonstrated that MBT resistance to rifampicin preserves longer with the biological microchip test than that with nutrient medium cultivation.

The paper is dedicated to the anniversary of Professor V. I. Puzik, Honored Science Worker. It gives the data of morphological studies from her dissertation and some sections of the dissertations supervised by V. I. Puzik. The paper also presents data on the diagnosis, clinical picture, and treatment of tuberculosis in adolescents. The problems of early detection, differential diagnosis, the significance of concomitant diseases and social factors in the course of tuberculosis are discussed. Emphasis is placed on the importance of drug resistance in adolescent patients with tuberculosis, which has been revealed in 63.3% of cases. Complex treatment with essential, reserve, and combined antituberculous drugs is recommended in relation to the sensitivity of Mycobacterium tuberculosis. It is also advisable to treat concomitant diseases and to prescribe pathogenetic agents enhancing the body's overall resistance.

Ninety adolescents with bacterial isolates of active forms of pulmonary tuberculosis were followed up. Drug resistance of Mycobacteria tuberculosis was revealed in 57 (63.3%) patients. Primary resistance was determined in 43 (47.7%) patients. The patients had not received antituberculous agents. Complete or partial coincidence of MBT resistance and sensitivity with the data of an infection focus. The course of tuberculosis during adequate treatment by using essential and reserve agents in the adolescents with varying MBT resistance was different. In patients (n = 18) resistant to 1-2 agents, the course of the disease little differed from that in those patients with drug-responding tuberculosis, except for later closure of decay cavities. In patients resistant to 3 drugs or more showed a slow course of the disease with significant residual changes in most patients.

The data are presented on 138 adolescents with active, advanced tuberculosis. M. tuberculosis were detected in the sputum and bronchial lavage of 75(54.3%) adolescents. 32 patients had M. tuberculosis resistant to drugs. 28 untreated patients demonstrated primary drug resistance (37.5%). Intensive combined treatment with consideration of bacterial resistance, administration of reserve drugs, wide spectrum medicines bring about positive results, but in patients with drug resistance positive dynamics is slow.