Biomedical subjects

L Alessio

Publications and source records attributed to L Alessio.

At least 73 records · Page 4Linked to original sources

PubMed1984

Cadmium concentrations in blood and urine of pregnant women at delivery and their offspring.

The levels of cadmium in blood (CdB) and in urine (CdU) were measured in 40 women at delivery and in their offspring. The women were not occupationally exposed to cadmium. The CdB levels in the pregnant women were significantly lower than in a control group consisting of 40 subjects of the same sex and age living in the same area. The difference can probably be ascribed to the physiological hemodilution that takes place in pregnancy. The CdU levels in the two groups were identical, which suggests that no mobilization of the metal from tissue deposits occurs during pregnancy. The presence of cadmium in the blood and urine of the newborn demonstrates that cadmium crosses the placental barrier. There was a rather high correlation between the CdU levels of mothers and offspring. Since only traces of cadmium are present in tissues at birth, it is speculated that the CdU levels in the newborn are influenced by the tissue deposits of cadmium in the mother. Further research is required to ascertain whether, in the case of women occupationally exposed to cadmium or living in cadmium polluted areas, transfer of the metal across the placenta can produce toxic effects in the foetus.

Adolescent↗

PubMed1984

Behaviour of plasma and urinary aluminium levels in occupationally exposed subjects.

Aluminium in urine (AlU) and in plasma (AlP) was determined in seven subjects occupationally exposed to environmental concentrations of aluminium below or equal to the TWA (5 mg/m3). The AlU levels in these workers were markedly higher than those found in the control group. The levels of the indicator were definitely higher at the end of the shift than at the beginning of the same working day; also, the AlU levels were higher on Friday morning than on Monday morning. After an interruption in work of two weeks, the values of the indicator underwent a marked reduction and were then only slightly higher than those of the control group. Occupational exposure to fumes produced higher AlU levels than exposure to dusts, and in the subjects exposed to fumes the AlU levels were clearly influenced by the degree of exposure. The levels of aluminium in plasma in the exposed workers on the other hand, hardly differed from the levels found in the control group. These data appear to indicate that, whereas AlU allows daily and weekly exposure to be evaluated, AlP cannot be used as an indicator of occupational exposure, at least in the case of brief exposures to environmental concentrations below or equal to the TWA.

Adolescent↗

PubMed1981

Behaviour of indicators of exposure and effect after cessation of occupational exposure to lead.

The behaviour of blood lead (PbB) and of some indicators of effect (erythrocyte protoporphyrin IX (EP), delta-aminolaevulinic acid dehydratase activity of erythrocytes (ALAD), and urinary delta-aminolaevulinic acid (ALAU)) were studied in subjects who had ceased working with inorganic lead for at least one year. Relations between these indices and chelatable lead (PbU-EDTA (lead in urine after injection of CaNa2 EDTA 1 g intravenously)), a test that is used to evaluate the lead deposits in the body, were also analysed. As a comparison, a group of subjects currently exposed was studied. In the workers with past exposure the PbB values were significantly lower, at the same PbU-EDTA levels, than those found in subjects at work. The relation between EP and PbU-EDTA shows that, corresponding levels of chelatable lead, the values of the erythrocyte metabolite are identical in the two groups. Considering the EP-PbB relation, however, at the same PbB levels the protoporphyrin values appear distinctly more altered in the subjects with past exposure. Similar results were obtained from a study of the relations between ALAD and PbU-EDTA and between ALAD and PbB. The relation between ALAU and PbU-EDTA, however, shows that, at the same PbU-EDTA levels the urinary metabolic in past-exposed subjects is distinctly lower than in subjects at work, while the relation between ALAU and PbB shows that, for similar blood lead values, the ALAU levels are identical. On the basis of the results obtained it is concluded that in subjects with past exposure, EP and ALAD can be used in establishing the persistence and extent of an "active deposit" of lead in the organism, while PbB is of very limited use.

Adult↗

PubMed1980

[Anoxic lesion of the working myocardial cell. Ultrastructural aspects].

A study was made of the effects of anoxia on the ultrastructure of the ordinary myocardial cell. Guineapigs were placed in a Plexiglass chamber, in which the flow of gases comprising the low oxygen mixture could be regulated. Blood samples were taken before, during and after acute and chronic anoxia experiments. Afterwards, five animals were kept alive for a further 10 days' follow-up, and six were used as controls. The material was perfused and fixed in accordance with various methods, and photographed through a Phillips M 300 electron microscope. Myocardial damage varied in area and incidence in function of the degree of anoxia, and appeared earlier, as well as at a higher oxygen content, in older animals, and in function of size. It may thus be supposed that such lesions appear earlier in man than in small animals. Due to containment of fuel costs, aircrew are more exposed than before to chronic hypoxia. The lesions indicated that chronic hypoxia leads to degeneration and regeneration, reflecting their relation to haemodynamic and biochemical mechanisms underlying the body's adaptation response.

Animals↗

PubMed1980