Frequent loss of heterozygosity at the Hcr1 (hepatocarcinogenesis resistance) locus on chromosome 10 in primary hepatocellular carcinomas from LFF1 rat strain.

Hepatocarcinogenesis sensitivity (Hcs1, 2) and resistance (Hcr1-3) loci have been identified by linkage analysis on rat chromosomes 7 and 1, and 10, 4, and 8, respectively. Cytogenetic studies documented deletions on chromosomes 3 and 6 of neoplastic rat hepatocytes. Hepatocellular carcinomas (HCCs) were produced in F1 hybrid rats between Long-Evans (LE) and Fisher 344 (F344) rats. Scanning of the above chromosomes for loss of heterozygosity (LOH) showed allelic imbalance (AI) at multiple regions on chromosomes 6, 7, and 10q. Detailed deletion mapping of chromosome 10 localized a putative suppressor Hcr1 gene to within a 3.2-cM interval flanked by D10Rat51 and D10Rat121. Two other distinct regions with frequent AIs were found inside the Hcr1 locus, at marker loci including DNaseI and Mrp genes, and in a segment including 4 consecutive markers (D10Rat64, D10Rat182, D10Rat113, D10Rat216). In 40% of HCCs, AI was seen at the p53 locus. AI on chromosome 7 occurred at the Hcs1 locus, where is located c-myc, which is amplified in HCCs, suggesting allelic gain. Most AIs occurred in poorly/moderately differentiated carcinomas, and a few events were seen in well-differentiated tumors on chromosomes 7 and 10. These data suggest that alteration of a cluster of oncosuppressor genes on 10q is important for HCC progression. The existence of AI on segments of rat chromosomes 6, 7, and 10, syntenic to chromosomal segments of human HCCs where chromosomal gains or deletions occur, suggests a commonality of some molecular events in the pathogenesis of HCCs in rats and humans. Our map provides information toward cloning putative oncosuppressor genes associated with this carcinoma.

[Echographic monitoring of follicular growth]. / Monitoraggio ecografico della crescita follicolare.

The sonographic monitoring of the ovarian follicular growth has been widely adopted, being a non invasive method, easily repeatable, well tolerated by the patient and low cost. A further impulse has been obtained by the endovaginal sonography. During a natural menstrual cycle the sonography can highlight the alterations that occur to the follicle and to the endometrium, supplying useful information on ovulatory timing. In pharmacologically induced menstrual cycles, the sonography enables us to evaluate the ovarian response to the therapy in tennis of number, size, site, and the type of growth of the recruited follicles, enabling us therefore to modulate the stimulation according to the individual response. Fluximetric studies are among the new applications the most promising, since they allow us not only to identify quickly the vascular structures, but also to supply a predictive value for the embryo implantation and the pregnancy evolution. The sonography at present proves to be irreplaceable in assisted reproduction programmes.

Prognostic value of hCG, progesterone, 17-beta estradiol and the echoscopic examination in threatened abortion during the first trimester.

The Authors refer on the validity of echoscopic examination and hCG, progesterone and 17-beta estradiol values in the prognosis of threatened abortion during the first trimester of pregnancy in 62 patients. The echoscopic examination allowed a prognosis to be made in accordance with the clinical evolution of threatened abortion in 90% of the cases; the plasma levels of hCG and progesterone in 87% of the cases; 17-beta estradiol in 83% of the cases. The Authors conclude that the simultaneous assay of hCG, progesterone and 17-beta estradiol plasma levels does not improve the prognostic validity of echoscopy but, in some cases, can provide essential details on the etiology of threatened abortion itself.