[Age-related and clinical-pathogenetic features of colorectal cancer associated with status of K-ras gene].

Activating mutation in K-ras gene is a key event in the pathogenesis of colon carcinoma. This study analyses frequency of this mutation in different age groups of colorectal cancer patients residing in North-Western Russia, and examines its relationship with essential clinical characteristics of tumor disease.

[Allelic distribution of the CYP1A1 in lung cancer patients, middle-aged tissue donors and in elderly people without cancer].

The genetic polymorphism of metabolizers of tobacco smoke carcinogens can influence individual susceptibility to lung cancer. The study was concerned with the Mspl-polymorphism of the CYP1A1 gene responsible for encoding aryl hydrocarbon hydroxylase. It also plays a role in the activation of polycyclic aromatic hydrocarbons (PAH).

[L-myc and GSTM1 polymorphism in cerebral glioma].

L-MYC and GSTMI polymorphisms were studied in glioma patients. L-MYC allele frequency in patients (L: 61/114 (54%); S: 53/114 (46%)) and controls (L: 108/204 (53%); S: 96/204 (47%)) was identical. S allele was associated with certain unfavourable clinical features of the disease.

[Determination of the role of DNA cytosine methylation in human genetic individuality].

By the restriction analysis method we established that methylation of the 5'-end cytosine in 5'-m5CC-3' duplexes had individual specific features. This genetic peculiarity did not change even in DNA from human stomach carcinomas.

[Modeling of alpha-superhelical proteins. Selection of sequence, synthesis, and properties].

An analysis of the alpha-tropomyosin primary structure suggests a periodic sequence able to form an alpha-superhelical conformation. A repeating unit (the heptapeptide monomer) was obtained by sequential synthesis in solution using pentafluorophenyl esters of the N-protected amino acids. The polyheptapeptide (Glu-Lys-Lys-Leu-Glu-Glu-Ala)n with an average molecular weight 6500 has been synthesized by polymerization of the heptamer.