In vitro methods to evaluate metal-cell interactions.

The aim of this study was to test different metals, widely employed in constructing prosthetic devices, by in vitro methods. Biological effects of such materials were analyzed through four different assays on human lymphocytes and granulocytes. The lymphocyte proliferation assay gave quantitative results, while the viability test showed the morphological appearance of the cells correlated well with previous results. NK cytotoxicity and granulocyte chemokinesis tests provided interesting data on leucocyte performance when challenged with metals. Therefore the present study adds new basic information on cell behaviour when metal products are present in the body, e.g. around devices implanted in human tissues.     

2,3,7,8-Tetrachlorodibenzo-p-dioxin plasma levels in Seveso 20 years after the accident.

In 1976, near Seveso, Italy, an industrial accident caused the release of large quantities of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) into the atmosphere, resulting in the highest levels of the toxicant ever recorded in humans. The contaminated area was divided into three zones (A, B, R) corresponding to decreasing TCDD levels in soil, and cohort including all residents was enumerated. The population of the surrounding noncontaminated area (non-ABR) was chosen as referent population. Two decades after the accident. plasma TCDD levels were measured in 62 subjects randomly sampled from the highest exposed zones (A and B) and 59 subjects from non-ABR, frequency matched for age, gender, and cigarette smoking status. Subjects living in the exposed areas have persistently elevated plasma TCDD levels (range = 1.2-89.9 ppt; geometric mean = 53.2 and 11.0 ppt for Zone A and Zone B, respectively). Levels significantly decrease by distance from the accident site (p = 0.0001), down to general population values (4.9 ppt) in non-ABR, thus validating the original zone classification based on environmental measurements. Women have higher TCDD levels than men in the entire study area (p = 0.0003 in Zone B; p = 0.007 in non-ABR). This gender difference persists after adjustment for location within the zone, consumption of meat derived from locally raised animals, age, body mass index, and smoking. There is no evidence for a gender difference in exposure, so variation in metabolism or elimination due to body fat or hormone-related factors may explain this finding. Elevated TCDD levels in women may contribute to adverse reproductive, developmental, and cancer outcomes.     

Vaccination with Freeze-Dried BCG

Sixty first-year medical students, negative to 1:2000 and 1:100 dilutions of old tuberculin (OT), were vaccinated with freezedried BCG vaccine. At six months, 98.3% were found to be positive reactors as ascertained by the intracutaneous (Mantoux) method, using 1:2000 and 1:100 dilutions of OT, and 73.7% as ascertained by the Heaf test, using a tuberculin PPD solution containing 100,000 T.U. per ml.     

Metabolic polymorphisms and the cancer risk: the evaluation of epidemiological studies]

Genetic modulation of environmental exposures associated with common malignancies is an attractive mechanism to explain differential susceptibility to tobacco or occupation-related carcinogens in the population. The paper reviews the evidence for an association between three genetically based metabolic polymorphisms (N-acetyltransferase, Debrisoquine, hydroxylase, aryl hydrocarbon hydroxylase), which have been implicated in the modulation of lung or bladder cancer risks. Fair to good support emerged for both an association of the acetylation phenotype with occupationally related bladder cancer and for an association of the debrisoquine metabolic phenotype with lung cancer, although in neither case was the evidence completely convincing. Epidemiologic evidence for an association between aryl hydrocarbon hydroxylase and lung cancer is presently problematic because of the difficulties in the assay and subsequent confounding factors.     

Physico-chemical and biological properties of actagardine and some acid hydrolysis products

Actagardine (originally designated as metabolite B or gardimycin) is a polypeptide antibiotic produced by fermentation of Actinoplanes strains ATCC 31048 and 31049. During the course of repeated fermentations two new compounds, coded D and E, were isolated. Some physico-chemical and biological characteristics of actagardine and of both compounds are presented. Compound D is derived from chemical transformation of actagardine.     

Prevention and early diagnosis of melanoma: a regional experience in Italy

Background Over the 1980s several education campaigns for prevention and early diagnosis of cutaneous melanoma have been reported from various parts of the world. Aim To improve incidence and prognosis of cutaneous melanoma in 1985 we started, in our area, an information and health education campaign aimed at identifying precursors of melanoma (congenital melanocytic nevi), suspicious lesions (changing moles) and subjects with increased risk of melanoma. Method Precursors and suspicious lesions were promptly removed, and high-risk persons entered the follow-up program. Result As a general effect of these activities the percentage of thin melanomas diagnosed in our division after 1985 increased from 25 to 37. Conclusion We believe that education campaigns and screening of a targeted population, particularly of subjects presenting increased risk of melanoma, may be helpful in the early diagnosis of melanoma.     

A case-control study of transient global amnesia.

To evaluate risk factors and prognosis of transient global amnesia (TGA), three groups of 30 subjects each affected respectively by: (1) first-ever TGA; (2) first-ever transient ischaemic attack (TIA); (3) depressive neurosis, were compared. Prevalence of cerebrovascular risk factors was similar in patients with TGA and TIA, but significantly lower in the third group. CT showed more hypodense lesions in TIA patients than in those with TGA. In a mean follow-up of 36 months, five TGA patients experienced a TIA and three others had recurrence of TGA, but none suffered stroke or myocardial infarction. In the TIA group, four had recurrence of TIA, two suffered a stroke and two others a myocardial infarction, whereas none had TGA attacks. None of the patients of the third group had any ischaemic event during follow-up. The similar prevalence of risk factors, but the different prognosis between TGA and TIA patients, suggest that TGA is an ischaemic event, probably not triggered by thromboembolism but by a different, possibly vasospastic, mechanism.