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The prevalence of the different phenotypes of alpha 1-protease inhibitor (alpha 1PI) was investigated in a group of 90 asthmatic patients and compared with that of a control group of 240 individuals representing the general population. The M2M2 phenotype occurred more frequently in the asthmatic group (p = 0.015). Plasma samples of 51 of the asthmatic patients randomly selected from the different phenotype groups identified were studied for the absolute plasma values of alpha 1-PI and the inhibitory capacity of plasma for porcine pancreatic elastase, and compared with those from 21 nonasthmatic individuals of the M1M1 phenotype. Although the asthmatic patients had higher absolute alpha 1PI values (p = 0.04), the plasma elastase inhibitory capacity was markedly reduced compared with the nonasthmatic subjects (p = 0.01). The functional efficiency of alpha 1PI from asthmatic patients of the M1M1, M1M2, and M2M2 phenotypes was significantly decreased compared with that of the nonasthmatic M1M1 individuals. Functional deficiency of alpha 1PI may be important in the pathogenesis of the inflammatory process that characterizes bronchial asthma.

This study sought to evaluate the in utero exposure to aluminum and status of selected trace elements in South African women at delivery since aluminum is known to be toxic in all developmental stages even at low concentrations. Serum aluminum was negatively correlated with aluminum in urine, both uncorrected and corrected for creatinine, which suggests the retention of aluminum in body stores. Serum copper and zinc levels were found to be high in this study population. Serum copper levels were negatively correlated with aluminum in serum (β = −0.095; p = 0.05). There was a marginal negative correlation between aluminum levels in serum and manganese levels in whole blood (β = −0.087; p = 0.08). Copper levels in maternal serum were negatively correlated with birth weight and the length of neonates. There were a number of positive correlations between maternal characteristics and birth outcomes. Mothers who consumed root vegetables frequently appeared to be protected from aluminum retention and increased body burden since their serum aluminum levels were found to be significantly lower. The findings of the current study can be used as a baseline for further research on aluminum exposure and its associated interactions and outcomes in vulnerable populations.

The aim of this study was to define bio-accumulation and excretion patterns of aluminium in newly employed potroom workers as well as changes in ambient aluminium levels in the potrooms of a modern aluminium smelter during the plant construction stage and one year into full production. A study was carried out on 115 newly employed volunteer potroom workers at various intervals, over a total period of 36 months. Before commencement of employment a structured questionnaire was completed by all study participants and the first collection of blood and urine specimens took place. As none of the subjects had ever worked in the aluminium industry before, they also served as their own controls. Atomic absorption spectroscopy was used to measure the aluminium content in the biological fluids and the content of the metal in the ambient air of the potrooms. Significantly, the study found an early and marked biological response to inhalation of very low levels of airborne aluminium. After only 12 months, the mean concentration of aluminium in serum had almost doubled; thereafter it levelled off. A mixed model analysis did not find any differences in the concentrations of aluminium in the serum of the subjects since the variation between subjects at any given time was much smaller than the variation within subjects. This may be an indication of the pronounced effect of aluminium inhalation on the kinetics of this metal in the human body. Furthermore, urinary excretion of aluminium by the potroom workers showed a linear increase reaching a concentration of only 49 microg l(-1) at the 36 month stage, suggesting a slow rate of elimination.

An ethnic study of 175 individuals, comprising 65 black and 110 white South Africans, has shown a conclusive difference in the frequency of the M1(ala213) haplotype of α1‐antitrypsin (P < 0.00001). The M1(ala213) haplotype occurred more frequently in the black group. In the latter group, the frequency of the M1(ala213) haplotype was the same in both controls (0.55) and asthmatics (0.53). However, there was a significant difference in the frequencies (0.19 and 0.36) for the respective white groups (P < 0.01), the frequency of the M1(ala213) haplotype being much higher in the asthmatics. Apart from the above differences, there was also a difference in the elastase‐inhibitory capacities of the homozygote phenotypes M1(val213) vs M1(ala213) (P < 0.0001), this capacity being lower in the latter phenotype. We conclude that the occurrence of the M1(ala213) allele of α1‐antitrypsin differs in various ethnic groups and may play a role in asthma.

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In order to ascertain the distribution of aluminium in normal and occupationally exposed sera, sizeexclusion chromatography using two fractionation techniques was applied: gel filtration (Sephadex G-100 SF) and HPLC (TSK G4000 SW). For each of the techniques, protein profiles obtained for control and exposed sera did not differ and aluminium was found to be associated with the same fractions.Ultrafiltration of sera using Centricon concentrators having a nominal cut-off of M r = 10000 confirmed the presence of high molecular mass and ultrafiltrable low molecular mass aluminium complexes in serum.Absolute quantitation and relative distribution of aluminium in the aforementioned complexes in original and spiked sera were determined using Zeeman atomic absorption spectrometry. It was found that the relative distribution of aluminium between high molecular mass and low molecular mass fractions was 79.1% and 19.6% in controls, compared to 91.3% and 8.7% in exposed sera, which is highly significant for both high molecular mass (p < 0.026) and low molecular mass (p < 0.004). After spiking both control and exposed sera with 400 g/l of Al, the distribution changed. The percentage of the aluminium bound to high molecular mass increased from 79.1% to 98.9% for controls, and from 91.3% to 98.4% for exposed sera, confirming the affinity of high molecular mass proteins, especially transferrin for aluminium. On the other hand, the percentage of aluminium bound to low molecular mass decreased after spiking to 1.12% for controls and to 1.6% for exposed sera. These differences were not statistically significant. This suggests that at high concentrations of total aluminium in serum, the percentage of the aluminium bound to the low molecular mass is lower but the absolute quantity of aluminium circulating as the low molecular mass complex is increased. This low molecular mass aluminium complex is thought to play an important role in intracellular accumulation of aluminium.An analytical method is proposed for the speciation of aluminium in serum.