[Enzymatic Preparation of Modified DNA: Study of the Kinetics by Real-Time PCR].

The effects of modified deoxyuridine triphosphates (mod-dUTPs) with different substituents at the C5 position of the pyrimidine cycle on the kinetics of PCR with Taq and Vent (exo-) DNA polymerases are studied. Substituents in mod-dUTP include carboxamide group and groups that are part of the side chains of alanine, valine, leucine, phenylalanine, tryptophan, or tyrosine. For each mod-dUTP, the yields of the target product are measured with the full substitution of dTTP. A fragment of bacterial DNA with a certain nucleotide sequence and a synthetic combinatorial DNA library of random nucleotide sequences are used as templates for amplification. For each mod-dUTP-template-polymerase combination, the correlation between the amplification efficiencies and yields of the target product are investigated. PCR product accumulation curves are influenced by both the template used and the presence of a modified substrate. The catalytic activity of Taq polymerase is higher when mod-dUTPs with short aliphatic substituents are used and decreases when the derivatives with long aliphatic, phenyl, and indole substituents are utilized. Vent (exo-) polymerase is less sensitive to the chemical structure of mod-dUTP. The dynamic measuring of DNA accumulation may be useful for optimizing the temperature-time PCR profiles individually for each of the mod-dUTP. The derivatives may be used in combination with Vent (exo-) polymerase to obtain modified DNA sequences for the method of selection of modified aptamers (mod-SELEX).

[Anesthesiologist-resuscitator: problems of training and maintenance of professional work].

The problems of psychological disturbances and insufficient profeccional skills amongst anaesthesiologists and intensive care specialists are discussed. The authors emphasized the need for special psychological education during refreshing courses and training period in residency. The official education in clinical residency should be updated in accordance with current view of speciality. It is necessary to use special simulators for better training of manual skill's and evaluation of knowledge more widely. The proper organization of the workplace is very important for successful performance and psychological condition of the personnel. The lack of profeccional Russian-language journals makes necessity for creation of a new textbook and periodical issue in paper and electronic format.

[Hormonal, radiation and combined therapy of locally advanced prostatic cancer (T3NXM0)].

The analysis is presented of combined treatment of locally advanced prostatic cancer (LAPC), stage T3NXM0, in 158 LAPC patients treated in 1998-2002. The patients were divided into four groups: group 1 (n=72) received hormones in parallel with radiation, group 2 (n=52) received only hormones, group 3 (n=27) received radiotherapy after failure of long-term (1 year and more) hormone therapy, group 4 (n=7) was given teleradiotherapy only. 3-year recurrence-free survival in patients with LAPC showed advantage of the combined treatment (82 +/- 0.1%) vs hormone (56 +/- 0.1%) or radiation (69.3 +/- 0.1%) therapy alone. It provides a high local control over the primary tumor and an increase of survival, prolongs distant metastases free period, improves the patients' quality of life and their adaptation.

[Experimental study of radiosensitizing effect of analogs of purines and pyrimidine bases in cultured HeLa cells]. / Eksperimental'noe issledovanie radiosensibiliziruiushchego deistviia analogov purinovykh i pirimidinovykh osnovanii na kul'tiviruemykh kletkakh HeLa.

The radio-sensitizing capacity of cultured HeLa cells was investigated by using a number of compounds, which are analogues of purine and pyrimidine bases. Agents (5-fluorouracil, ftorafur, mercaptopyrine) used in chemotherapy for tumors for many years and some compounds (allopurinol and theophylline) that are sterically close to purine and pyrimidine bases and clinically used for various purposes, but have no cytotoxic activity against tumors cells were tested. Fluorouracil was shown to potentiate the action of gamma-radiation when the agent was given used before radiation or used in the concentrations producing no cytotoxic effect. Allopurinol and theophylline do not possess a radio-sensitizing effect. There was a more pronounced radiosensitization in the concurrent use of a double combination of agents and radiation and the greatest cell death rates were observed in the concurrent use of three agents (5-fluorouracil, ftorafur, and methylcytosine) and gamma-radiation.

[The role of radiotherapy in the surgical treatment of patients with breast cancer]. / Rol' luchevoi terapii pri khirurgicheskom lechenii bol'nykh rakom molochnoi zhelezy.

The 5- and 10-year results of treatment of 1,377 breast cancer patients were analysed with reference to the type of surgical procedure. On the basis of the similarity of the end results, similar rates of recurrence incidence and distant metastases and the absence of metastasis in the subclavicular area after Patey's operation coupled with radiotherapy, a high effectiveness of the latter treatment was established. It contributed to a radicality comparable to that of a radical mastectomy.

[Role of radiation therapy in the complex treatment of breast cancer]. / Rol' luchevoi terapii v kompleksnom lechenii raka molochnoi zhelezy.

The survival rate in breast cancer patients depending on the radiotherapy method employed was analysed. Based on the longterm follow-up of 1385 patients, it is shown that of all the methods of radiotherapy the preoperative irradiation, including the primary tumor site and all zones of regional metastatic spread, seems to be most preferable. Postoperative radiotherapy is a less advantageous technic, and it may be in use in case of lymphnodes metastases and an evident violation of anablastic principles during the operation. An accessory use of chemotherapy would improve the prognosis for breast cancer patients.

[Effectiveness of prophylactic irradiation of the cervical lymphatics in malignant tumors of the nasopharynx]. / Effektivnost' profilakticheskogo oblucheniia limfaticheskikh putei shei pri zlokachestvennykh opukholiakh nosoglotki.

The effectiveness of prophylactic irradiation of areas of the neck commonly involved in metastatic spread was studied in 276 patients with nasopharyngeal malignancies who were followed up during 5 and more years. The analysis was carried using such criteria as the decrease in the frequency of recurrent regional metastases, distant metastases and increase in 5-year survival. The absorbed doses ranged 45-50 Gy. The procedure was followed by a decrease in the frequency of regional metastases (3.4% versus 32.7% in untreated patients). The frequency of distant metastases decreased nearly by half (19.5% versus 31.7%). Five-year survival rates increased significantly from 49 to 65.5%. This relationship was recorded for all histological types of tumors. Application of prophylactic irradiation in doses of 45-50 Gy prevents local subclinical metastasis development in most patients.

[Single preoperative radiation and short-wave treatment of breast cancer]. / Odnokratnoe predoperatsionnoe luchevoe i SVCh-vozdeistvie pri lechenii raka molochnoi zhelezy.

A total of 93 patients were assigned to receive either radiation treatment alone (group 1) or in combination with local microwave-induced hyperthermia (group 2) prior to mastectomy. The treatment results were compared. Within a two-year follow-up period, all patients of group 2 remained free of relapse, metastases being registered in 2 (6.2%) cases. In group 1, relapse was observed in 1 case, whereas metastasis--in 7 (11.5%). The study failed to establish drug-induced tumor pathomorphosis in 12.5% in group 2 and 73.8% in group 1. The procedure did not interfere with surgery, nor was it followed by an increased postoperative complication rate.

[Prognostic factors of the probability of the occurrence of complications in the radiation therapy of malignant neoplasms]. / O faktorakh prognozirovaniia veroiatnosti vozniknoveniia oslozhnenii pri luchevoi terapii bol'nykh zlokachestvennymi novoobrazovaniiami.

The authors present an analysis of the causes of radiation induced complications in 383 patients referred to the Chair of Clinical Radiology from different medical institutions of the country. It was found that under distant gamma therapy, to prevent the development of complications the value of TDF-factor should not exceed 105--110, for the associated radiotherapy--130--140, and that for close focal roentgenotherapy--130--150. In vast majority of patients (95.3%) the complications resulted from surpassing the normal tissue tolerance. To prevent radiation injuries it is suggested to take into consideration the TDF-factor values, while in planning radiotherapy to choose such schedules of irradiation, which preclude any surpassing of the tolerance of normal tissues and organs adjacent to the tumor.

[Cell proliferation parameters in human rectal tumors and their transformation during fractionated irradiation]. / Parametry proliferatsii kletok opukholei priamoi kishki cheloveka i ikh izmenenie pri fraktsionirovannom obluchenii.

Human rectal adenocarcinoma is characterized by considerable variation in labelling index for different tumors as well as different areas within the same tumor. Therefore, the averaged indices of tumor cell proliferative activity do not mirror the actual heterogeneity of tumor. Conventional schedules of fractionated irradiation resulted in a decreased labelling index and varying response in most cases under study. Following large-dosage fractionated irradiation, labelling index remained unchanged or showed a slight decrease. The rate of DNA synthesis is practically unaffected by the available schedules of fractionated irradiation.

[Combined treatment of malignant tumors of the external auditory canal and the middle ear]. / Kombinirovannoe lechenie zlokachestvennykh opukholei naruzhnogo slukhovogo prokhoda i srednego ukha.

Clinical outcomes have been analyzed for 50 patients with malignant tumors in the external acoustic meatus (EAM) and the middle ear (ME). The patients have received combined therapy with pre- or postoperative radiation. Combined treatment for EAM and ME cancer is a method of choice which increases survival of patients and improves quality of their lives. In primary cancer of the ear preoperative radiation is preferable, while postoperative radiation is required in advanced disease, in moderately or poorly differentiated tumors when the risk of recurrence is especially high.