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Biomedical subjects

N Castellino

Publications and source records attributed to N Castellino.

At least 37 records · Page 2Linked to original sources
PubMed1998

Blood lead concentration and biological effects in workers exposed to very low lead levels.

A longitudinal study was carried out on two groups of workers engaged in tin/lead alloy welding in the telecommunication sector. The risk of exposure was evaluated by measuring levels of airborne lead (PbA) and the amount of lead absorbed (PbB). The-correlated effects were assessed by determining zinc protoporphyrin (ZPP) and hemoglobin levels (Hb) and red blood cell (RBC) count. We also recorded subjective symptoms reported by workers. One group of welders composed of 365 subjects underwent two monitoring sessions performed in 1991 and 1995, respectively (Group A). A second group of welders (whose number fluctuated between 148 and 247 subjects) underwent yearly testing for 7 consecutive years (1988-1994; Group B). Results indicated a very low risk of lead exposure during microwelding operations (PbA range, 1.5-24 micrograms/m3). In fact, blood concentrations of Pb (range, 5-55, micrograms/dL) among both groups of welders were significantly higher than those in the general population in Rome (PbB range, 5-16 micrograms/dL); nevertheless, they were significantly lower than the Occupational Safety and Health Administration's permissible exposure limits ZPP determined only in Group B of welders ranged from 5 to 16 micrograms/dL (median, 22 micrograms/dL). No variation was found in the other biological parameters investigated, and no health effects were observed. During the study period, the introduction of some technological innovations led to a further reduction in Pb exposure and, subsequently, to its total elimination. PbB concentrations gradually declined to lower values (6-36 micrograms/dL), and it was interesting to note that ZPP concentrations also decreased to normal levels (range, 2-47 micrograms/dL; median, 11 micrograms/dL), demonstrating that the effect of lead on heme synthesis may occur even at very low levels of Pb exposure.

Adult↗
PubMed1998

Occupational exposure to chromium--an assessment of environmental pollution levels and biological monitoring of exposed workers.

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.).

Adult↗
PubMed1985

Metabolic fate and cardiovascular effects of arsenic in rats and rabbits chronically exposed to trivalent and pentavalent arsenic.

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.

Animals↗
PubMedDate not supplied

Puberty onset in Northern Italy: a random sample of 3597 Italian children.

Entering puberty is one of the most important milestones in life. Studies from around the world have shown that age of pubertal changes onset can vary with race and ethnicity, environmental conditions, geographical location and nutrition. In the last century, the onset of puberty progressively shifted back towards younger ages in several European countries, with a levelling off in the last decades. The aim of our study was to describe the prevalence of secondary sexual characteristics in a group of children living in Northern Italy comparing them with the percentile values published by Tanner in 1976. We enrolled 3496 children drawn from public schools and evaluated height, weight and pubertal stages. The analysis of our data evidenced that the 50th percentile age of puberty onset in both sexes decreased by about 1 yr compared to data published by Tanner. Mean body mass index (BMI) z-score was significantly higher (p = 0.01) in pubertal than in pre-pubertal girls, on the contrary it was higher (p = 0.005) in pre-pubertal than in pubertal boys. In conclusion, our study found that girls and boys of our region are beginning pubertal development about 1 yr earlier than Tanner's British population. Taking into consideration the 3rd percentile age for Tanner's breast stage 2 in girls and testicular volume (TV) of 4 ml in boys, the current internationally used cut-off age for precocious puberty, i.e. 8 yr for girls and 9 yr for boys, can be maintained in our population.

Age Factors↗
PubMedDate not supplied

Altered cytokine production in mice exposed to lead acetate.

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/l 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-gamma) 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/l of Pb, while a further increase in IL-4 production was associated with a decrease in INF-gamma production in mice exposed to 400 mg/l of Pb. On the other hand, Pb exposure did not induce changes of serum IL-2 (involved also in the Th0 immune pattern). Our findings indicate that low level Pb exposure enhances a Th2 response. A high Pb does can either stimulate the Th2 immune activity or reduce the Th1 response; the result is an imbalance between Th1 and Th2 activation.

Animals↗
PubMedDate not supplied

[Health promotion in the occupational setting: what are the prospects in the Italian situation?].

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.

Ethics↗
PubMedDate not supplied

Lead inhibits growth and induces apoptosis in normal 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 (p < 0.01), 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.

Animal Testing Alternatives↗