Olvanil: more potent than capsaicin at stimulating the efferent function of sensory nerves.

The capsaicin analogue olvanil stimulated an increase in cutaneous blood flow when injected intradermally into the anaesthetised rabbit, as measured using a 133Xenon clearance method. Olvanil was found to be a 10-fold more potent vasodilator (on a molar basis) than capsaicin. The effect of both vasodilators was significantly inhibited by the calcitonin gene-related peptide (CGRP) receptor antagonist CGRP-(8-37). These findings suggest that olvanil stimulates the efferent function of cutaneous sensory nerves in a more potent manner than capsaicin. We therefore suggest that olvanil is a useful pharmacological tool for studying the activity of neuropeptides released from sensory nerves.     

Epidemiology of congenital pigmented naevi: I. Incidence rates and relative frequencies

Pigmented naevi (PN) were clinically diagnosed in 1083 newborn infants from a series of 531,831 consecutive livebirths examined in fifty-nine hospitals in South America. Isolated PN (IPN) were seen in 989 (0.2%) non-malformed infants, while PN associated with other congenital anomalies (APN) were observed in ninety-four (1.0%) malformed babies. Incidence rates calculated from the fifty-nine hospitals were very variable due to under-reporting, which might have been as high as 80%. The PN were classified by their location, number, size, texture, and colour. Observed locations were compared with random expected distributions based on the surface proportions of the newborn. IPN were preferentially found on the chest and abdomen, with a low concentration on the head and upper limbs. No examples were observed on soles or palms. IPN were single in 90% of cases. Size was small (1–9 mm) in 29%, medium (10–;40 mm) in 63%, and large (over 40 mm) in 8% of cases. Abnormal texture, (rugose, raised, and/or hairy) was found in 7–11% of IPN. Colour was brown in 68%, black in 21%, and of other colours in 11%. The large IPN tended to be multiple in number and abnormal in texture. Small IPN tended to be black. IPN on the chest and abdomen were more frequently small, non-black, and of normal texture; those found on the back tended to be black and abnormal in texture; black IPN were also frequent on the upper limbs; large IPN frequently affected the lower limbs. The APN did not differ from the IPN in their number, size, texture, or colour. APN were less common than expected on the back and upper limbs. An association was observed between the PN and the following four congenital anomalies: ear deformities, preauricular appendages, angiomas, and other skin anomalies. The differences in distribution of PN in the newborn infant and that in the adult that have been previously published suggest that most of the PN found in the adult are not congenital.     

Tumour cords in 52 human bronchial and cervical squamous cell carcinomas: inferences for their cellular kinetics and radiobiology

Tumour cords have been measured in 33 cases of squamous cell carcinoma (SCC) of the bronchus and 19 cases of SCC of the uterine cervix. The overall mean cord radius for SCC in both sites was 104 microns, similar to the overall mean for various tumours in rodents. For tumour cells adjacent to blood vessels in cords of SCC, the mean Mitotic Index was 2.1% and from this value a rapid potential doubling time could be inferred (approximately 31 to 66 h). The proportion of dead cells within cords of cervical SCC was higher than in animal tumours. Using measured values for cord radius and published equations that describe the diffusion and consumption of oxygen in metabolising tissue, an attempt was made to calculate the oxygen partial pressure in vessels of cords of these SCC.