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The reduction of chlorocomplexes of gold(III) from muriatic solutions by nanocrystal powders of palladium and platinum at 110 and 130 °C under hydrothermal conditions and the action of microwave irradiation has been investigated. The structure and composition of the solid phase have been characterized by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and chemical methods. Bimetallic particles with a core-shell structure have been revealed. The obtained particles are established to have a core of the metal reductant covered with a substitutional solid (Au, Pd) solution in case of palladium, and isolated by a gold layer in the case of platinum. The main reason for such a difference is the ratio between the rates of aggregation and reduction. It has been shown by the example of the Au-Pd system that the use of microwave irradiation allows us not only to accelerate the synthesis of particles but also to obtain more homogeneous materials in comparison with conventional heating., (© 2011 American Chemical Society)

Epstein-Barr virus (EBV) is an etiological agent of a number of benign and malignant human diseases, such as infectious mononucleosis (IM), Hodgkin's lymphoma (HL), and non-Hodgkin's lymphoma (NHL). EBV latent membrane protein 1 (LMP1) gene (recognized as a viral oncoprotein) of various clinical and geographical origin was found to have different types of amino acid mutations affecting its biological activity. Since there was no information on the strain differences in LMP1 of EBV persisting in Russia, the authors made a sequence analysis of LMP1 samples amplified from the biological materials of Russian patients with IM, HL, and NHL and healthy individuals. The studies have shown that LMP1 variants of Russian origin are a mixed heterogeneous group containing both the earlier characterized and presumably new genetic variants. Among the point amino avid substitutions, the mutations S366T, F106Y, 185L, and E328Q associated with the enhanced transforming activity of a LMP1 molecule and its reduced cytotoxicity. There was no specific association between the certain Russian variants of LMP1 and the specific forms of the disease (IM, HL, and NHL).

Epstein-Barr virus (EBV) is known to be closely associated with the development of anaplastic nasopharyngeal carcinoma (NPC) in some malignancy endemic regions in South-East Asia. LMP1 gene is one of the EBV latent genes, which encodes a latent membrane protein. LMP1 gene is thought to be a classical oncogene since it morphologically transforms cells in vitro and induces tumors in experimental animals in vivo. LMP1 is one of a few genes which is expressed in NPC tissues. It was first shown that C-terminus of LMP1 gene obtained from NPC patients in South-East Asia contained a deletion of 30 base pairs (bp). However, this deleted LMP1 gene was then found in the EBV isolates persisting among healthy virus carriers and patients with other EBV-associated abnormalities from both NPC endemic and non-endemic regions. The aim of this investigation was to accomplish a molecular biological analysis of EBV LMP1 genes obtained from Russian NPC patients. To this end, the authors isolated and sequenced the LMP1 clones amplified from the tumor tissues from 7 NPC patients at the N. N. Blokhin Russian Cancer Research Center and primary blood lymphocytes (PBL) from 6 healthy donors. As a result, the authors could not find the deletion of the above-mentioned 30 bp in NPC LMP1 clones, but could in one healthy donor (PBL-2). A functional analysis revealed no significant differences between LMP1 variants with or without 30 bp deletion in their capacity to activate NF kappa B and jun/AP-1 transcription factors. Nevertheless, Russian NPC-derived LMP1 variants as compared with those from PBLs featured some specific amino acid exchanges. These data indicate that the 30 bp deletion of LMP1 gene is not a factor that predisposes to NPC in Russia.

The authors analyze the results obtained at comprehensive examination of 123 patients with multifocal synchronous and metachronous cancer of the upper respiratory tracts and the lungs. Cancer of the larynx and the lungs was registered in 107 patients, multifocal cancer of the pharynx and lungs in 16 patients. Synchronous and metachronous cancer of the larynx and the lungs was diagnosed in 48 (44.9%) and 59 (55.1%) patients, respectively. High efficacy of endoscopic diagnosis is shown for multifocal cancer of the larynx and lungs, pharynx and lungs.

A new method for diagnosing human malignant tumors is dealt with, which is based on fluorescence of malignant neoplasms and their adjacent normal tissue. To measure the fluorescence spectra, a fiber optic system and a multi-channel optic spectral analyser have been designed. While analysing the resultant spectra, a greater fluorescence excess was observed in the red wave band in the tumors than in normal tissue. Further investigations are required in order to use the method in question in clinical diagnosis.

The value of various endoscopic methods in diagnosing lymphosarcoma was assessed in 149 suspects aged 3-14 years. Fiberscopy of the upper digestive tract was performed in 130 children of whom 43 revealed lymphosarcoma in Waldeyer's ring whereas in 87 lymphoid hyperplasia was detected. Laparoscopy was carried out in 17 children, esophagogastroduodenoscopy--2 and colonoscopy--in one case Endoscopic methods proved to be of high diagnostic value, easily available and safe for examination of children suspected for lymphosarcoma.

The paper presents 10-year results of endoscopic examinations which have been performed of late in the Endoscopy Department of the All-Union Cancer Research Center. Altogether 36 patients with primary tracheal tumors (PTTs) were evaluated. The study of PTTs endoscopic pattern suggested the conclusion on feasibility of visual differential diagnosis of various tumors and assessment of the tumor spread along the bronchial tree.

Proceeding from 2626 fibroscopic examinations of the upper respiratory tract during radiotherapy of 492 cancer patients, the most appropriate time of control endoscopic examinations have been defined, endoscopic criteria for the evaluation of the efficacy of therapy of primary tumors of different parts of the upper respiratory tract have been determined. The evaluation of the efficacy of therapy by the common otorhinolaryngological method was compared with that of the fibroscopic method of examination. The efficacy of radiotherapy by changing endoscopic pictures is most vividly expressed in laryngeal cancer after delivering the dose of 30-40 Gy (49-66 units of TDF), in laryngeal and nasopharyngeal cancer 50 Gy (82 units of TDF) and in lymphosarcoma of the throat ring 20 Gy (33 units of TDF). In the use of the speculum and fibroscopic methods difficulties in the organ inspection and differentiation of changes were noted in 31.7 and 16.1% of the cases including 64.3 and 11.9% in laryngopharyngeal cancer and 80.9 and 1.8% in nasopharyngeal cancer. Tumor regression in concomitant involvement of the tonsils by lymphosarcoma develops not uniformly. A positive time course is first of all noted in lymphadenoid masses: in the palatine and lingual tonsils and then in the pharyngeal, tubal and laryngeal tonsils. Complete tumor regression after irradiation at a dose of 20 Gy (33 units of TDF) is noted in 50% of lymphosarcoma patients. In 13.2% of cases doses of 50 Gy (82 units of TDF) and 60 Gy (99 units of TDF) are required for complete regression of lymphosarcoma of the throat ring.

The analysis of the data of 352 fiber bronchoscopies performed in 142 cases of small-cell lung cancer before, in the course and after chemotherapy or chemoradiation treatment makes a case for complex application of X-ray and endoscopic procedures since the data on diagnosis and response to treatment obtained under the separate use of either procedure agreed in 67.7% and 80.3% of cases only.