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Biomedical subjects

R Herber

Publications and source records attributed to R Herber.

At least 37 records · Page 2Linked to original sources
PubMed1987

Zinc protoporphyrin as an indicator of lead exposure: precision of zinc protoporphyrin measurements.

In lead-exposed workers many factors affect the relationship between the levels of lead and of zinc protoporphyrin (ZPP) in blood. When the zinc protoporphyrin level is used to assess the lead in the blood level, the analytical accuracy of the ZPP and the PbB determinations should be known. Also the variability of lead exposure over time is an important parameter of this assessment. The absolute and relative precision of ZPP measurements with two brands of ZPP meters (AVIV and ESA) were compared. The absolute precision of the ZPP measurements is not constant for the AVIV meter, but is constant for the ESA meter. The relative precision for both brands of meters decreases with increasing ZPP levels. Between the AVIV and the ESA meters, a significant difference in response, irrespective of the kind of anticoagulant used, was observed. The regression equations between PbB and ZPP levels were studied. Different factors can affect the relationship between PbB and ZPP, e.g. variability in lead exposure, the time-lag between the increase of PbB and ZPP, and the precision and accuracy of PbB and ZPP measurements.

Humans↗
PubMed1987

Renal function of workers with low-level cadmium exposure.

The influence of occupational exposure to cadmium on renal function was examined in 27 male cadmium workers from plants with second-degree usage of cadmium. The levels of cadmium in the blood and urine and various protein concentrations in the urine and serum were determined. The urinary levels of beta 2-microglobulin, retinol-binding protein, and N-acetyl-beta-D-glucosaminidase were statistically significantly increased in workers with urinary cadmium levels above 50 nmol/l. SDS-PAGE electrophoresis with silver staining is probably a sensitive indicator of the early effects of cadmium on protein excretion. The currently recommended biological exposure limits may have to be lowered.

Cadmium↗
PubMed1983

Lead uptake from vegetables grown along highways.

Blood-lead levels were measured in tenants of vegetable gardens located in close proximity to busy highways (average: greater than 25000 vehicles per workday) in the Netherlands. For comparison, blood-lead levels were determined in tenants of vegetable gardens located away from busy traffic. The results indicate that there is no significant difference between the geometric mean blood-lead levels of the two populations, despite a 2-3-fold difference in the lead content of their vegetables, and despite frequent consumption of these vegetables in the exposed group. Mean PbB-values were around 0.48 mumol/1 (100 micrograms/1), which is well below existing health guidelines and slightly below the levels found in another recent survey of Dutch suburban residents.

Adult↗
PubMed1983

[Influence of anaerobiosis on the sterol composition of Mucor hiemalis].

Strict anaerobic cultures of Mucor hiemalis lead to major modifications of the quantitative and qualitative composition of sterols. Sterols of which the lateral chain contains an ethyl or ethylidene group in C24 are for the first time brought to evidence in a Mucorales. Isolation in the same conditions of E-ethylidene-24 (28) lanostene-8 ol-3 beta lets us suppose that sterols, which are absent in aerobic cultures, are derived from this triterpene of 32 C atoms.

Aerobiosis↗