Histamine levels in the blood of humans experimental animals under normal conditions and following vaccination]

The authors present the results of study of the blood histamine content in intact rabbits and in the animals to which commercial vaccines with a different degree of reactogenic property for man were administered. The blood histamine level was also studied in practically healthy individuals and in those vaccinated with inactivated tick-borne encephalitis vaccine. The blood histamine content varied in intact rabbits from 4 to 10 microgram/ml, averaging 6.4 +/- 0.09 microgram/ml. Animal immunization caused elevation of the blood histamine content correlating with the reactogenic properties of the preparations for man: vaccines with low reactogenic properties--inactivated encephalitis and live measles vaccine produced no significant changes in the index under study; as to the typhoid vaccine with sextatoxoid, and smallpox vaccine with marked reactogenic properties--they stimulated significant histaminemia in rabbits. Revaccination of man against tick-borne encephalitis with the inactivated cultural vaccine caused an increase in the blood histamine content.     

Faster synthesis and slower degradation of liver protein during developmental growth

A study is presented of the liver protein gain during the early stages of postnatal development. Fractional rates of protein synthesis and degradation were determined in vivo in livers of 4-day-old mice. At this age, liver protein accumulated at a rate of 18% per day. Synthesis was measured after the injection of massive amounts of radioactive leucine. Degradation was extimated as the balance between synthesis and accumulation of stable liver proteins, or from the disappearance of radioactivity from liver protein previously labelled by the administration of NaH14CO3. We found that the neonatal livers: (1) synthesize 139% as much protein per unit time and unit mass as adult tissue, which is accounted for by a higher ribosome concentration (synthesis per mg of RNA was the same); (2) retain 39% of the newly synthesized protein as stable liver components (compared with 48% in adult mice); (3) degrade protein at 56% of the rate in the adult liver. This lower rate of degradation is quantitatively the most significant difference between the growing and non-growing liver.     

Stepwise synthesis of oligonucleotides. XXII. The synthesis of Tpsi-loop fragments of yeast tRNAIVal and their analogs

The method of the combined use of nucleolytic enzymes was used for the synthesis of Tpsi-loop fragments of yeast valine tRNA and their analogs. Dinucleoside monophosphates, trinucleoside diphosphates and tetranucleoside triphosphates having the sequences of fragments 54-57 and 59-62 or their analogs were synthesized.     

Comparison of the radiosensitivity of chromosomes during the S and G2 periods in regenerating rat liver cells

Radiosensitivity of chromosomes at S and G2 periods was studied by means of autoradiography technique in cells or regenerating liver of rats treated with X-rays at the doses of 150 and 300 r. The experiments were made so that the interval between irradiation and mitosis in S and G2 cells was equal. The results have shown that under the experimental conditions there are significant differences in the yield of chromosome aberrations between the labelled and intact cells. This withnesses for the existence of differences in radiosensitivity of chromosomes at different periods of mitotic cycle.     

Occurrence of human papillomavirus infection in cervical intraepithelial neoplasia. A retrospective histopathological study of 317 cases treated by laser conization

The aim of the study was to compare the histological outcome of the cone specimens with the diagnoses of the preoperative biopsies, to assess the distribution of histological features consistent with human papillomavirus (HPV) infection and, finally, to analyse the impact of cellular HPV features on classification of cervical intraepithelial neoplasia (CIN). The study comprised a population of 317 women treated for CIN by laser conization during the period 1983-85. A total of 634 cervical specimens (317 preoperative biopsies and their corresponding cones) were studied retrospectively for CIN classification and examined for morphological signs of HPV infection. For presentation of the results, we used a modified terminology for CIN. Low-grade (LG) CIN included borderline lesions and CIN I, while high-grade (HG) CIN included CIN II and CIN III. The blinded histopathological review revealed HG CIN both in the preoperative biopsies and the cones in 71% of the cases. LG CIN or benign lesions were found in the preoperative biopsies and their corresponding cone specimens in 6% of the study population. HPV features were present in 65% of the preoperative biopsies, and were most prevalent in women under 29 years of age (p < 0.001). Thirteen percent of the total biopsy material was downgraded. The downgrading was most prevalent among original CIN II (p = 0.009) and HPV-negative biopsies (p < 0.001). This study demonstrates that CIN lesions are frequently associated with HPV features, which are significantly more prevalent in the youngest women. Concomitant HPV features do not influence the CIN classification.