A human placental polydeoxyribonucleotide (PDRN) may promote the growth of human corneal fibroblasts and iris pigment epithelial cells in primary culture.

The optimal concentration of a human placental polydeoxyribonucleotide (PDRN) preparation (100 microg/ml) enhances the growth of human corneal fibroblasts in primary culture depending upon the donor age. In particular, this effect is very consistently reproducible with donors over 60 years of age (p = 0.0028), suggesting a selective benefit of PDRN in the tissue culture of senescent cells. Moreover, this drug may promote the development of human iris pigment epithelium (IPE) cells with much lower concentrations of fetal bovine serum than those suitable for the culture of IPE. Lastly, the use of a 'gauze disk' on the pieces of the corneal explants improves the efficiency of growth of the control fibroblast primary cultures.

Timing of breast cancer surgery in relation to the menstrual cycle: an update of developments.

It is well-established that hormones have multiple effects on breast cancer. Some, but not all studies indicate that the phase of the menstrual cycle (and hence hormonal status) at the time of breast surgery may influence survival. In this paper we review the literature in this area, explore how it is possible that such an association may occur, and note that randomised studies which unambiguously determined the phase of the cycle at the time of the operation are lacking. We go on to describe an ongoing self-randomised trial designed to address this problem and present preliminary results which show that only about 75% of the women ovulated during the cycle in which the operation took place, and that the established prognostic factor Ki-67 varied with the phase of the cycle in women who ovulated. It is too early to assess the significance of this finding.

Antiviral activity of FA-11H on the infectivity and replication of herpes simplex virus type 1 in cultured cells.

The highest concentration lacking cytotoxicity (h.c.l.c.) of the acid FA-11H, related to ester FA-11 (ethyl 4-trifluoromethyl-2-methylthio-5-pyrimidinecarboxylate), was determined on Vero cultured cells. At this concentration (300 micrograms/ml) FA-11H produced an 81.4% inhibition of herpes simplex virus type 1 infectivity with respect to the plaque formation detected in control infected cultures. This inhibitory activity was substantiated by studies on progeny production. FA-11H revealed a higher therapeutic index than that of the related ester FA-11. However, the therapeutic index of FA-11H appeared to be lower than that of its potassium salt. These results indicate that the presence of potassium ions could facilitate the internalization and therefore the antiviral activity of the anions corresponding to analysed compound.

Evaluation of the trophic effect of human placental polydeoxyribonucleotide on human knee skin fibroblasts in primary culture.

A simple assay capable of evaluating the trophic effect of growth factors or active principles on human skin diploid fibroblasts in primary culture has been developed. The results indicate that at physiological concentrations (20-100 micrograms/ml) a human placental polydeoxyribonucleotide (PDRN) preparation enhances the growth of human skin diploid fibroblasts of the knee in primary culture. This effect is consistently reproducible in the case of patients over 60 years of age, and may explain previously reported data on the successful clinical applications of human placental preparations, suggesting a selective benefit of PDRN in wound healing when compared to other treatments.