[Polyposis of the colon and cancer]. / Polipoza na debeloto chervo i rak.

Polyposis of the colon is a colon cancer predisposition syndrome. Familial adenomatous polyposis (FAP) accounts for 1% of the cases of inherited colorectal cancer (CRC). The National Register of inherited CRC and polyposis of the intestines keeps track of 18 patients from 14 families with FAP. Eight of them have been operated of CRC, on 6 patients preventive colectomy with ileorectal anastomosis has been done and four patients refused surgery. Colectomy has been done due to the malignant development also on a female patient with difused juvenile polyposis with adenomatosis. Of three patients under surveillance with the Peutz-Jeghers syndrome, surgery has been done on one female patient with ileus and bleeding large polyps.

[The molecular biology and genetics of colorectal carcinoma]. / Molekulna biologiia i genetika na kolorektalniia kartsinom.

There is vast evidence in support of the idea that accumulated genetic changes (mutations) are the underlying cause of neoplasia development. This multi-step process is aptly illustrated by colorectal carcinoma (CRC), usually developing in the course of decades, and presumably requiring at least seven genetic events to complete its development. In CRC the oncogenes most frequently undergoing mutation are c-k-ras and c-myc, and among tumor suppressant genes--APC, MCC, DCC, p53. An updated model of the molecular bases for adenoma occurrence and its evolution into carcinoma is presented. Inheritance of a single gene only which has undergone mutation augments substantially the predisposition to CRC. This is noted in a clearcut manner in the hereditary syndromes familial adenomatous polyposis (FAP) and hereditary non-polypous colorectal carcinoma (HNPCC). Recent studies along these lines suggest that the genetic defect in FAP increases the incidence of tumor initiation through functional impairment of the APC gene which is a gene regulator of the enhanced colorectal mucosa proliferation. Contrarily, the defect in HNPCC involves mainly the tumor progression through mutation of the DNA repair genes (MMRs), which are regulators of the genome stability. The study of hereditary syndromes give rise to a new concept for the occurrence and development of sporadic and inherited cancer in humans.

[Population polymorphism of silver-stained nucleolar organizer chromosome regions in man]. / Populiatsionnyi polimorfizm okrashivaiushchiksia serebrom iadryshkoobrazuiushchikh raionov khromosom u cheloveka.

Activity of nucleolar organizer regions (NORs) of acrocentric chromosomes determined by Ag-staining was comparatively studied in 40 individuals of Bulgarian and 40 individuals of Russian populations. Chromosome 21 was found to be significantly more often stained in both populations. The other NORs did not differ significantly in staining from the means. No differences were noted between individual NORs, in respect of the intensity of Ag-staining in both populations, except chromosome 15 which showed markedly decreased staining capacity in Russians. The data obtained are compared with those published in literature concerning four other populations.

[RV polymorphism of the chromosomes in newborn infants]. / RV-polimorfizum na khromozomite u novorodeni.

The authors examined the routine variants (RV) of the karyotype of 100 clinically healthy newborns--49 girls and 51 boys. Secondary constriction of the long arm of one of the homologues of the chromosome I was found in 2% of the newborns; of the chromosome 9--in 4% of the chromosome 16--in 3%. Secondary constriction in both homologues was observed in the chromosome I in 1%; in the chromosome 9--in 1% and in the chromosome 16--4%. Secondary constriction of the short arm of both homologues was found only in the chromosome 16 in 3%. The large acrocentric chromosomes showed extended proximal area (p5) in 34%, but diminished (pI)--in 8%. The small acrocentrics with p5 were found in 14% of the newborns, but with pI--in 7%. Enlarged satelites were observed in 1% in the both groups of acrocentrics. Difference between the homologues in respect to the short arms was observed in 32,3% of the pairs of the great acrocentrics and in 47,5% of the small acrocentrics. Distribution of the Y chromosome according to the size in 51 boys was of Gaus character q1--0%, q2--29,4%, q3--33,3%, q4--25,5% and q5--11,7%. It is possible that Y chromosome with a size of q1 could be connected with definite pathology.

[Comparative study of the effect of haloperidol and maptil on the karyotype and immunoproliferative response of lymphocytes]. / Sravnitelno prouchvane na deistvieto na khaloperidola i mazheptila vurkhu kariotipa i imunoproliferativniia otgovor na limfotsita

The author examined the action of haloperidol and magetyl on the mitotic activity, blast transformation and karyotype of the lymphocytic cultures, obtained from the peripheral blood in vitro. The experiments were carried out on flymphycytes, obtained from ten healthy individuals. Nontreated cultures, obtained from the same cultures, were used as controls. The following concentrations were used: haloperidol--0.1 mkg/ml, 10 mkg/ml and 10.0 mkg/ml; mageptyl--2.0 mkg/ml, 10,0 mkg/ml and 50 mkg/ml. There was a significant inhibition of the mitotic and blast transformation index after using concentrations of 10.0 mkg/ml both of haloperidol and magentyl. Concentration of 50.0 mkg/ml was toxic for the lymphocytes, obtaine from all donors. Furthermore the two preparations did not induce genomic mutations. Polyploidia, established in the treated cultures, varied slightly from that of the nontreated cultures. There was a weak mutagenic activity of the two preparations at chromosomal level in a concentration of 10.0 mkg/ml.