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L’obesita infantile e attualmente riconosciuta come un importante problema di sanita pubblica. Infatti negli ultimi 30 anni la frequenza di sovrappeso nei bambini e triplicata. Eliminando i rari casi di obesita secondaria, le ragioni di questo fenomeno risiedono nel cambiamento dello stile di vita che comprende non solo le abitudini alimentari, ma anche la diminuzione dell’attivita fisica per la crescente abitudine di stare in casa trascorrendo il tempo in attivita sedentarie. In eta adulta e ormai ampiamente dimostrato che l’obesita riduce la qualita di vita ed aumenta la morbilita e la mortalita. L’obesita infantile e invece una condizione relativamente recente, anche se in grande espansione. Non esistono quindi studi a lungo termine sull’impatto dell’insorgenza precoce di obesita sul rischio cardiovascolare e sulle altre patologie correlate in eta adulta, ma ci sono ampie evidenze di un anticipo in eta adolescenziale delle complicanze dell’obesita finora osservate nell’adulto. La terapia dell’obesita infantile si basa fondamentalmente su un corretto apporto alimentare e aumento dell’attivita fisica. Per raggiungere lo scopo e pero necessario intervenire su tutto il nucleo familiare insegnando un corretto stile di vita, nutrizionale e comportamentale.

Female Swiss mice typically display signs of puberty at about 33–37 days of age. In the present investigation (96 female mice tested in 8 Pb exposure levels, n = 12 per exposure level), the time to puberty onset was markedly influenced by exposure to dietary lead. While modest increases in blood lead concentrations from a normal background of 2–3 to 13.2 μg/dl delayed the onset of puberty by 15–20% to about 40–43 days, reducing blood lead from 2–3 to 0.7 μg/dl was associated with an acceleration of puberty to 21 days, an enhancement by over 30%. This dose–response relationship represents novel findings of possible ecological as well as public health significance and indicates that lead is able to induce biologically significant changes at blood lead levels previously thought to be without effect.

Ghrelin, a natural GH secretagogue, is predominantly produced by the stomach. Ghrelin has other actions including orexant activity, modulation of energy balance, and modulation of endocrine and nonendocrine functions. Ghrelin secretion is increased by fasting and energy restriction but decreased by food intake, glucose, insulin, and somatostatin. Ghrelin secretion does not seem to be a function of age; in fact, morning ghrelin levels after overnight fasting in prepubertal and pubertal children are similar to those in young adults. To clarify whether children and adults have the same sensitivity to the inhibitory effect of food intake, we studied the ghrelin response to a standardized light breakfast (SLB) in 10 prepubertal lean children whose results were compared with those recorded in 19 normal-weight adults. Basal ghrelin levels in children (median, 224.5; 25th to 75th percentile, 122.0–447.7 pg/ml) and adults (338.0; 238.0–512.0 pg/ml) were similar. SLB inhibited ghrelin levels in adults (263.0; 190.0–399.0 pg/ml). However, no change in ghrelin levels after SLB (206.5; 105.0–274.0 pg/ml) was recorded in children. Thus, food intake inhibits ghrelin secretion in adults but not in children. Ghrelin refractoriness to inhibition by food intake in children would reflect a peculiar functional profile of the ghrelin system in childhood.

The effect of lead (Pb) ingestion on hematological parameters in male and female Swiss mice was assessed. Eight different doses of Pb were administered through preparation of different feeds. The levels of Pb in the diet were designed to provide exposure below (0.6 to2.0 microg/dl) and above (2.0-13 microg/dl) normal background. One litter of mice was exposed to each Pb dose, with the mother given the feed 1 day after mating, and the mother and offspring continuing to receive the feed until the litter was 90 days old. Male and female mice receiving below normal background levels of dietary Pb displayed enhanced red blood cell (RBC) production as measured by increased numbers of RBC and increased hemoglobin and hematocrit values. However, as the blood Pb levels approached 10 microg/dl there was a marked decrease in RBC production. These findings are significant since Pb was biologically active in a stimulating manner below typical background levels (2.0 microg/dl) while adversely effecting red cell synthesis at above background levels (7.0-13 microg/dl) encountered in the environment by humans.

The purpose of this study was to estimate the lead intake from crystalware resulting from short-term contacts with beverages, under conditions that are likely to occur to a consumer. The extraction ability of different kinds of beverages was estimated by comparison with 4% acetic acid under conditions of continuous contact for 3 h. It was found that lead release increased in the following order: cola drinkHAcwhiskywhite wine. Under conditions of repeated use under different scenarios, lead release showed a steep decrease with increasing number of contacts, for both wine and cola drink. The maximum lead intake resulted from the cola drink, corresponding to an ingestion of 14.5 micrograms Pb for consumption of 350 ml beverage. Assuming a fixed contribution from the diet of 71 micrograms/day, in the six scenarios taken into consideration, total daily lead intake levels ranged from a minimum of about 76 micrograms up to a maximum of 86 micrograms lead. As these values, converted on a weekly basis, would correspond to 35% and 40% PTWI respectively, significant health risks resulting from the ingestion of beverages in contact with crystalware can be excluded. Finally it was found that the use of a dishwater did not affect significantly the release of lead into wine, while release into cola drink was slightly but significantly increased after the third cycle.

The amount of airborne lead absorbed by the body during occupational exposure depends not only on lead concentration in workplace air, but also on the granulometric distribution of the aerosol. The Occupational Safety and Health Administration (OSHA) set the lead Permissible Exposure Limit (PEL) at 50 micrograms/m3 on the basis of Bernard's model and a number of assumptions, including assumption "C", which predicts that the first 12.5 micrograms/m3 are made up of fine particles (aerodynamic diameter1 micron) whereas the remaining 12.5 micrograms/m3 consist of particles1 micron. Occupational exposure to airborne lead at a concentration of 50 micrograms/m3 and a granulometric distribution calculated according to the above mentioned assumption, leads, in the model, to a mean blood level of 40 micrograms/dl. In the present study, we tested the validity of assumption "C" in the environmental air of a factory that manufactured crystal glassware containing 24% lead oxide. An 8-stage impactor was used to measure the particle size of airborne dust collected from personal and area samplings. Results indicate that, on the whole, assumption "C" cannot be considered valid in the work environment investigated in this study. As a result, lead absorption levels in exposed workers may be noticeably different from those predicted by the OSHA model. We therefore suggest that in order to make a correct evaluation of the risk of occupational exposure to lead, it is essential to integrate total airborne lead concentration with a measurement of the granulometric distribution of the aerosol.

In an aircraft construction factory where adhesives containing Cr(VI) compounds were used, the risk of chromium exposure was studied by assessing airborne chromium levels and urinary levels of chromium excretion. Chromium exposure was evaluated by personal sampling over a period of 4 hr in a group of 16 occupational workers selected from a group of 55. Chromium absorption was determined by collecting urine samples from all subjects (n = 55) at 3 different times: prior to the work-shift at the beginning of the working week and prior to and after the workshift at the end of the working week. Each urine sample was tested for chromium and creatinine concentration. Results showed very low exposure to airborne chromium, since values obtained (0.02-1.5 micrograms/m3, GM: 0.17, GSD: 5.34 micrograms/m3) were significantly lower than the ACGIH Hygiene Standard (50 micrograms/m3). Likewise, urinary chromium excretion (0.16-7.74 micrograms/g creat.) was higher than excretion in the general population (0.07-0.17 microgram/g creat.) but lower than BEI-ACGIH (30 micrograms/g creat.). The greatest difference between excretion levels measured before and after the workshift was 2.44 micrograms/g creat, i.e. 4 times lower than the difference proposed by ACGIH (10 micrograms/g creat.).

Determination of Pollutants in the Air of Textile Industries: Valentino RIMATORI. et al. Institute of Occupational Medicine, Catholic University -In order to investigate the pollution degree in three weaving and dyeing and in two clothing factories, the authors measured the indigo, oil mist, hydrogen sulfide (H2S), sulfur dioxide (SO2) and total particulate matter (TP), as well as the biphenyl, ophenylphenol and p-phenylendiamine (PPDA) concentrations. H2S ranged from

The frequency of early-onset neonatal sepsis without prophylaxis is 1-5/1.000 live births. Since year '70 the most frequent causative microorganism is the group B Streptococcus (S. agalactiae, GBS), followed by Escherichia coli. The mortality rate is now reduced to 4% due to the improvement of neonatal intensive care. In the USA, the incidence of GBS early-onset neonatal sepsis has been markedly reduced by the application of the guidelines released by the Centers for Disease Control (CDC). This strategy, however, is not effective on occurrence of late-onset neonatal group B streptococcal disease. In Italy, the application of CDC guidelines is not customary, and different, often complex, protocols of obstetrical-neonatological integrated approach are applied. The frequency of infectious risk has made the GBS a paramount problem for the neonatologist, even for the legal responsibility issues resulting from the multiplicity of possible options. To reach the best level of protection of the newborn against early-onset GBS infection, the working group of providers of prenatal, obstetric, and neonatal care of the functional area of Cuneo issued an integrated protocol, in order to perform the GBS screening with the optimal culture method suggested by CDC guidelines in the highest possible number of pregnant women, and to standardize the obstetrical and neonatal management.

Summary Objective The presence of both the GH secretagogue (GHS) receptor and ghrelin in the pancreas indicates an involvement of this hormone in glucose metabolism. Ghrelin secretion is increased by fasting and energy restriction, decreased by food intake, glucose load, insulin and somatostatin in normal adults; however, food intake is not able to inhibit circulating ghrelin levels in children, suggesting that the profile of ghrelin secretion in children is different from that in adults. Moreover, how ghrelin secretion is regulated in childhood as a function of fat mass is still unclear. Design and subjects We studied the effect of oral glucose load (75 g solution orally) on circulating total ghrelin levels in 14 obese children (group A, four boys and 10 girls, aged 9·3 ± 2·3 years) and 10 lean children (group B, five boys and five girls, aged 9·7 ± 3·8 years). Measurements In all the sessions, blood samples were collected every 30 min from 0 up to +120 min. GH, insulin and glucose levels were assayed at each time point. Results Glucose peaks following an oral glucose tolerance test (OGTT) in groups A and B were similar; however, both basal and OGTT-stimulated insulin levels in group A were higher than in group B ( P < 0·05). Basal total ghrelin levels in group A (281·3 ± 29·5 pg /ml) were lower ( P < 0·0005) than in group B (563·4 ± 81·5 pg / ml). In both groups A and B, the OGTT inhibited total ghrelin levels ( P < 0·005). In terms of absolute values, total ghrelin levels in group A were lower ( P < 0·0005) than those in group B at each time point after glucose load. The percentage nadir in total ghrelin levels recorded in group A ( − 25% at 90 min) was similar to that recorded in group B ( − 31% at 120 min). Total ghrelin levels were negatively associated with BMI ( r = 0·5, P < 0·005) but not with glucose or insulin levels. Conclusion Ghrelin secretion is reduced in obese children. It is, however, equally sensitive in both obese and lean children to the inhibitory effect of oral glucose load.

A number of studies have documented that Pb exerts immunotoxic effects on T lymphocytes. In studies designed to explore this general response over a broad dose range, female Swiss mice were administered six different diets containing Pb acetate 1 day after mating. During lactation, the mothers received the same feed given during pregnancy, and the same diets were administered to the offspring for 9 months after weaning. At the end of exposure, blood Pb level in the offspring was determined, and possible changes in two type 1 cytokines (IL-2, INF-gamma) and one type 2 cytokine (IL-4) in the serum were measured. At higher dietary Pb levels (40 and 400 ppm), a significant increase in IL-4 production was associated with a profound decrease in INF-gamma and IL-2 production. At the lowest Pb diet level (0.02 ppm), which resulted in a blood lead level of (0.8 microg/dL), which is below background (2-3 microg/dL) values in humans, increases in INF-gamma and IL-2 production along with a significant decrease in IL-4 production were observed. The findings provide evidence of a reversal of lead-induced cytokine skewing depending on the blood lead concentration. As blood lead concentration increases, there is a notable skewing toward Th2, while the pattern is reversed favoring Th1 development at lower blood lead values. The present findings are also notable since they indicate the potential for dietary Pb to have significant biological effects below normal background concentrations.

We report results from a replication in second and third generation female mice of accelerated time to puberty associated with low Pb exposure levels . Mice in the 2nd generation study are offspring of mice from the initial study; the 3rd generation mice are offspring from mice in the 2nd generation study. For each generation the time to puberty onset was markedly influenced by exposure to dietary lead. Modest increases in blood lead concentration from a normal background of 2-3 to 8-13 micro g/dl delayed the onset of puberty by 10-20% from a normal of 33-35 days to about 40-43 days; reducing blood lead from 2-3 to 0.7 micro g/dl was associated with profound acceleration of puberty to 21 days, an enhancement by over 30%. This dose-response relationship, which replicates previous novel findings, has possible ecological as well as public health significance and indicates that lead is able to induce biologically significant changes at blood lead levels previously thought to be without effect.

Previous investigations have shown that Pb exerts immunotoxic effects. Object of this study were Th1 and Th2-type immune responses of mice to Pb exposure. Adult Swiss male mice were administered 0, 40 and 400 mg/1 of Pb (as acetate) in drinking water for 14 days . At the end of the treatment, blood Pb was determined and two Th1 cytokines (IL-2, INF-γ) and one Th2 serum cytokine (IL-4) were measured. A significant increase in IL-4 production was observed in the mice exposed to 40 mg/1 of Pb, while a further increase in IL-4 production was associated with a decrease in IFN-γ production in mice exposed to 400 mg/1 of Pb. On the other hand, Pb exposure did not induce changes of serum IL-2 (involved also in the ThO immune pattern). Our findings indicate that low level Pb exposure enhances a Th2 response. A high Pb dose can either stimulate the Th2 immune activity or reduce the Th1 response; the result is an imbalance between Th1 and Th2 activation.

It is necessary to standardize some parameters for occupational health and safety of their professional diver: risk assessment of work duty, appropriate training program and sanitary surveillance. European Diver Technology Committee (EDCT) gathers the member State's experience about safety procedures, professionals and sanitay surveillance. EDTC criterions to whom it is possible to refer in Italy waiting specific regulations are reported.

BACKGROUND: Previous investigations on the ghrelin gene reported three common polymorphisms (Arg51Gln, Leu72Met, and Gln90Leu), but their role in overweight and obese individuals remains to be clarified. OBJECTIVE: To ascertain whether these genetic variants could influence ghrelin secretion and play a part in predisposing to earlier onset of obesity or in modulating the overweight phenotype in childhood. DESIGN AND METHODS: Mutational analysis of the entire ghrelin gene and total and acylated plasma determinations were performed in 81 obese or overweight children and adolescents (46 were obese and 35 overweight: Ob/Ow). We also recruited 168 normal-weight healthy controls (72 young adults and 96 children) for mutational or plasma ghrelin analysis. RESULTS: Median total and acylated plasma ghrelin concentrations were significantly lower in Ob/Ow individuals than in controls (175 pg/ml compared with 345 pg/ml, P

In a circumscribed rural area of Lucania (Italy) three cases of pleural mesothelioma have been identified: two men, 83 and 52 years old and a 78 year-old woman, who all had in common the fact of being shepards in that area. Possible asbestos pollution sources have been sought: we have immediately excluded an asbestos manufactured articles pollution, however we have highlighted the presence of "green stones", which had always been known to the local inhabitants and which, in three subsequent campains of collecting and chemical-mineralogical investigations, have resulted partly constituted by amphibole asbestos, classified as tremolite. Official institutions are organising a series of initiatives to verify the hypothesis of a causal relationship between the presence of tremolite and the cases of pleural mesothelioma, and preventive initiatives aimed at reducing exposure and to a sanitary surveillance. Similar problems had been identified in Turkey, Greece, Corsica, New Caledonia and recently in eastern Sicily.

The aim of our study was to evaluate the age of the onset of pubertal characteristics in a population of Northern Italy and to compare our data with the pubertal staging scale defined by Tanner in 1976. These observations may help us to verify if even in Italy there is a positive secular change in sexual maturation, as has been observed in many European countries. We studied 3510 children (1868 males and 1642 females) aged 6-15 years, born between 1983 and 1996. In every subject sexual maturity was evaluated according to Tanner stages. We calculated the percentile distribution for ages of attainment of B2 and PH2 stages for females and G2, PH2 and testicular volume = or4 ml (VT4) for males. In females the percentile values for B2 were: 3rd=8.1, 50th=10.5, and 97th=12.6 years. In males the percentile values for G2 and VT4 were: 3rd=8.8 and 9.1 years respectively, 50th=11 years, and 97th=13.4 and 13.3 years respectively. 3rd, 50th, and 97th centiles for pubic hair stage 2 were 8.1, 10.6 and 12.6 years for females and 8.8, 11.2 and 13.4 years for males. For all stages an earlier pubertal development was seen in comparison with Tanner data. One hundred-twenty-five girls had already reached menarche. Median (interquartile range) age at menarche was 11.9 (11.4-12.4) years showing a decrease compared with Tanner values. Our data clearly demonstrate a positive secular trend in pubertal development and point out the need of having updated references values of the timing of sexual maturation for the whole Italian population.

Ghrelin, a natural GH secretagogue, exerts remarkable endocrine and non-endocrine activities such as orexigenic effect and modulation of the endocrine and metabolic response to variations in energy balance. Ghrelin levels have been reported to be negatively associated to insulin secretion, enhanced in anorexia and reduced in obesity. Ghrelin levels in childhood have never been evaluated. We measured morning ghrelin levels after overnight fasting in 29 healthy lean children (NC) and in 36 obese children (OBC). The results were compared with those recorded twice in 3 different sessions in healthy lean adults (NA). In NA ghrelin levels showed good within-subject reproducibility without gender-related differences. Ghrelin levels in NC [(median; 25 degrees -75 degrees centile): 426.0; 183.0-618.0 pg/ml] were similar to those in NA (380.5; 257.7-551.7 pg/ml). Ghrelin levels in OBC (229.5; 162.5-339.5 pg/ml) were lower (p0.03) than in NC (426.0; 183.0-618.0 pg/ml). Both in NC and in OBC, ghrelin levels were independent of gender and pubertal status. In all children, ghrelin levels were negatively associated (p0.05) to weight excess (r=-0.24), insulin (r=-0.28) and IGF-I (r=-0.4) levels. In conclusion, these findings demonstrate that morning ghrelin levels after overnight fasting show good within-subject reproducibility, and are similar in both sexes and do not vary from childhood to adulthood. In childhood, circulating ghrelin levels are reduced in obese subjects being negatively correlated to overweight and insulin secretion.

Previously published studies indicate that hepatotoxicity is associated with high blood lead (Pb) levels in animal models and humans. The present investigation evaluated the effects of in vivo Pb exposure via drinking water on mouse hepatocyte survival in vitro when blood Pb concentrations reflected those seen in children in urban and rural settings (2–15 μg/dl). The findings indicated a biphasic dose–response with low concentrations associated with a modest decrease in hepatocyte survival, while at the highest concentration, survival was significantly enhanced (60%). Since these responses were associated with concentrations normally encountered by children, follow-up investigations are warranted.

The study of Jayjock and Lewis, `Implication of Hormesis for Industrial Hygiene’, represents a challenge for the scientific community to consider hormesis as a possible working hypothesis for redefining risk assessment strategy for low-dose exposures in the realm of industrial hygiene. This invited commentary aims at examining some aspects of the study for which no proven and conclusive scientific evidence has yet been found, such as the limited nature of some statistical tests, the calculation of the safety factor, the place occupied by hormesis in industrial hygiene and, finally, the impact that scarce knowledge of this phenomenon and rejection by part of the scientific community has on the possibility of using hormesis in the safeguarding of workers’ health.

Lead (Pb) is an environmental toxicant that can induce structural and functional abnormalities of multiple organ systems, including the central nervous and the immune systems. The aim of this study was to evaluate the effects of extracellular Pb supplementation on the cellular content of the metal and on the proliferation and the survival of normal rat fibroblasts. We found that the concentration of Pb in the culture medium was 0.060 microM and the normal Pb concentration in rat fibroblasts was 3.1 +/- 0.1 ng/10(7) cells. Then we exposed the cells to increasing concentration of Pb (as Pb acetate) from 0.078-320 microM. We observed a dose-dependent inhibition of cell proliferation after 48 h, which was already apparent at a concentration of 0.312 microM (p = 0.122) and became statistically significant for concentration higher than 0.625 microM (p = 0.0003 at 5 microM). Cell proliferation was completely compromised at 320 microM Pb total inhibition of cell proliferation. To investigate the mechanisms of Pb-mediated inhibition of cell proliferation, we evaluated the occurrence of apoptosis in the same cells and found that cytosolic DNA fragments, hallmark of apoptotic cell death, increased significantly at Pb concentrations from 2.5-10.0 microM. The occurrence of apoptosis was also confirmed by FACS analysis which showed the appearance of a subdiploid peak at Pb concentrations from 5-20 microM. The distribution of cells in the cell cycle showed a dose-dependent accumulation of cells in the G0/G1 phase mainly compensated by a decrease in the percentage of cells in the S phase. In conclusion, our results demonstrate that induction of apoptosis contributes to the Pb-induced inhibition of cell proliferation in rat fibroblasts.

The effects on normal rat fibroblasts of lead supplementation (as lead acetate) in the medium were examined. The amount of lead acetate ranged from 0.078 microM to 320 microM, at 14 concentrations. The normal level of lead in the medium was 0.060 microM, and the normal concentration of lead in the fibroblasts was 3.1 +/- 0.1 ng/10(7) cells: these represented the control conditions. On studying fibroblast proliferation and survival after incubation for 48 hours, a lead acetate dose-dependent inhibition of cell proliferation was observed, the results being shown to be significant by ANOVA (p0.01), and suggesting a significant dose-response relationship. Apoptosis, evaluated by quantifying cytoplasmic DNA fragments, differs significantly between the lead levels tested. The distribution in the cell cycle, evaluated by using a fluorescence-activated cell sorter, showed a dose-dependent accumulation of cells in the G0/G1 phase, with a compensatory decrease in the percentage of cells in the S phase. Moreover, the occurrence of a subdiploid peak confirmed that apoptosis was more evident when the medium was supplemented with lead acetate at concentrations of 5-20 microM. The inhibition of cell growth is probably due to a direct inhibition of cell proliferation.

Over the past decades advances in sciences and medicine have improved living and health conditions and lengthened life expectancy. These benefits are associated with an increase in prevalence of chronic degenerative diseases. With their multi-factorial aetiology these diseases are influenced by life styles and personal habits and require prolonged medical care and high social costs. Now days health is no longer considered as the absence of disease but a state of mental, physical and social well-being. The World Health Organization has defined health promotion as "the process of enabling people to increase control over and to improve health". Since the 70s in the USA many health promotion programmes have been proposed, especially by large corporations, in order to ensure a more efficient, productive and motivated work-force, to reduce health insurance costs and to provide a better company image. Workplaces,--particularly when the working population is relatively stable--are excellent areas for health promotion programmes because workers can be monitored over a long period of time. The most successful programmes are aimed at modifying behaviour in risk patterns (smoking, alcohol abuse, eating disorders, etc.) through information, active participation, screening, follow-up, personalized programmes, changes in the working environment, physical exercise programmes. These health promotion programmes are extremely hard to develop for Italian workers. Most firms are small or very small and much still remains to be done to eliminate well-known occupational risk factors. The current flexibility of modern work patterns could constitute a further obstacle.

Specimens from skin lesions were examined simultaneously for herpes simplex virus (HSV) and varicella-zoster virus (VZV) by direct specimen testing and shell vial culture in single-test systems. For direct testing, cells in a single specimen well were stained with a combination direct-indirect immunofluorescence stain by using two fluorescent tags. A total of 203 fresh specimens were tested in parallel. Of these, 100 specimens contained too few cells for the direct VZV comparison and 91 contained too few cells for the HSV comparison. After these specimens were eliminated, the sensitivities and specificities, respectively, of the dual direct test were 86.1 and 97.3% for HSV compared with single culture and 92.2 and 100% for VZV compared with single direct testing. Shell vial monolayers in the combined cultures were stained for both viruses by the same method. A total of 305 fresh specimens were cultured in parallel by dual- and single-culture methods. The sensitivities and specificities, respectively, of the combined culture compared with separate cultures were 100 and 98.4% for HSV and 87.9 and 99.2% for VZV. The combined methods gave a performance comparable to those of single tests, required less specimen volume, and were less costly to perform.

Castellino, N., and Aloj, S. (1969).Brit. J. industr. Med.,26, 139-143. Intracellular distribution of lead in the liver and kidney of the rat. The distribution of lead in intracellular fractions of liver and kidney has been studied in rats for nine days after intravenous injection of 100 μg. of lead (210Pb) per rat. The radioactivity and the protein nitrogen have been measured in the homogenates and in the nuclei, mitochondria, microsomes, and cell sap. Lead penetrates the cells quickly, being present in all fractions one hour after injection. During the first 72 hours the relative amounts of lead in the different fractions varied, which ruled out the possibility that all the differences could be explained by redistribution after homogenization. The distribution of the metal within the cell probably depends upon differences in the nature and the stability of bonding to intracellular structures. The binding of lead within the mitochondria seemed to be particularly stable, only 24·4% of the radioactivity being removed by washing with 0·25 m sucrose or 0·001 m ethylenediaminetetra-acetate or 0·001 m diethylenetriaminopenta-acetate in 0·25 m sucrose. This finding is discussed in relation to haem biosynthesis within the mitochondrion.

SummaryL'elimination biliaire du cerium apres injection intraveineuse de cerium 144 a ete etudiee par catheterisme du choledoque chez le rat Wistar. Les courbes d'elimination de bile et de cerium en fonction du temps sont donnees pour cinq intervalles differents apres l'administration du radioelement. L'elimination du cerium par les selles est comparee a l'elimination du cerium par la bile. Il n'y a pas de reabsorption intestinale du cerium.L'administration d'un choleretique ne modifie pas l'elimination du cerium par les voies biliaires.Dans la bile, le cerium parait lie a une proteine.

The kinetics of the distribution and excretion of lead ( 210 Pb) were studied in rats for 14 days after single intravenous injections of 100 μg. of lead per rat. The results show that in the blood the lead is bound mainly to the cells, and that the ratio of lead in the cells and plasma is constant throughout the whole period. 210 Pb is rapidly distributed in the tissues, the highest concentrations being in the kidneys, liver, and bones. The kinetics of the disappearance of 210 Pb from the organs and tissues follow the pattern of first order reactions. The disappearance curves in the blood, plasma, haematic cells, and some other tissues can be expressed as sums of exponential functions. In contrast, the removal of metal from the bone tissue occurs at a constant and extremely slow rate. The metal is excreted by the faeces and urine. The rates reach their maxima within 24 hours and decrease asymptotically afterwards. More 210 Pb was excreted in the faeces (35·7%) than in the urine (15·9%) during the 14 days of observation.

(1963). Experimental Research on Toxicity of Furfural. Archives of Environmental Health: An International Journal: Vol. 7, No. 5, pp. 574-582.

Male rats and female rabbits exposed for eighteen and ten months, respectively, to 50 micrograms/ml of trivalent arsenic (As III) in drinking water showed reduction of stroke volume (SV) and cardiac output (CO) and increase of vascular resistance (VR), while no cardiovascular change was observed in male rats receiving 50 micrograms/ml of pentavalent arsenic (As V) for eighteen months. The exposed animals showed specific alterations in some neurohumoral and effector mechanisms regulating cardiovascular function (CF). Elevated levels of urinary As were found in all treated groups. However, there were significant differences in the urinary levels of dimethylarsenic acid (DMA), monomethylarsenic acid (MMA) and inorganic As, which depended on both animal species and the valency state of As. Thus, As(III) was methylated to a greater extent than As(V) in rats, with less elimination of inorganic As, while rabbits had a lower capacity to methylate As and to retain As in tissues than rats. Either cardiovascular effects or metabolism of As seemed to depend on its valency state and animal species.

Male rats and female rabbits exposed for eighteen and ten months, respectively, to 50 µg/ml of trivalent arsenic (As III) in drinking water showed reduction of stroke volume (SV) and cardiac output (CO) and increase of vascular resistance (VR), while no cardiovascular change was observed in male rats receiving 50 µg/ml of pentavalent arsenic (As V) for eighteen months. The exposed animals showed specific alterations in some neurohumoral and effector mechanisms regulating cardiovascular function (CF). Elevated levels of urinary As were found in all treated groups. However, there were significant differences in the urinary levels of dimethylarsenic acid (DMA), monomethylarsenic acid (MMA) and inorganic As, which depended on both animal species and the valency state of As. Thus, As(III) was methylated to a greater extent than As(V) in rats, with less elimination of inorganic As, while rabbits had a lower capacity to methylate As and to retain As in tissues than rats. Either cardiovascular effects or metabolism of As seemed to depend on its valency state and animal species.