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H van Beek

Publications and source records attributed to H van Beek.

8 recordsLinked to original sources
PubMed1992

Increased metallothionein in the liver and kidney of patients with amyotrophic lateral sclerosis.

To evaluate the putative role of metals and trace elements in the pathogenesis of classic amyotrophic lateral sclerosis, we studied the metallothionein levels in liver and kidney samples obtained at autopsy from 24 patients with amyotrophic lateral sclerosis and 18 controls. To assay metallothioneins and copper, cadmium, and zinc bound to metallothioneins, we used high-performance liquid chromatography directly coupled to flame atomic absorption spectrometry. Total cadmium, zinc, and copper concentrations were determined separately with the use of graphite furnace atomic absorption spectrometry with Zeeman background correction. The median liver metallothionein level was 60.3 mg/kg (range, 9 to 318 mg/kg) in the patients with amyotrophic lateral sclerosis and 12.6 mg/kg (range, 0 to 104.5 mg/kg) in the controls. In the kidney, median metallothionein levels were 126.9 mg/kg (range, 44 to 387 mg/kg) in the patients with amyotrophic lateral sclerosis and 64 mg/kg (range, 13.1 to 187 mg/kg) in the controls. Total zinc, cadmium, and copper concentrations, as measured by atomic absorption spectrometry, were not significantly different in patients vs controls. Our finding of elevated metallothionein levels in organs from patients with amyotrophic lateral sclerosis may indicate an increased exposure to metals.

Adolescent↗
PubMed1991

[The impacted upper cuspid].

Impacted upper cuspids may give rise to problems, such as the formation of cysts and the resorption of adjacent teeth. Early diagnosis (before the age of 12) is important. Proper timing of extraction of the deciduous cuspid may lead to spontaneous correction. When the position of the cuspid is unclear, orthopantomography and a lateral skull film may be helpful. Palatally impacted cuspids should be exposed surgically and moved into position by orthodontic treatment. Labially impacted cuspids are exposed by relocation of an attached gingival flap. The experience of the authors with the treatment of 81 patients are reported.

Adolescent↗
PubMed1990

[Lead poisoning in cattle in north Netherlands. October 1989-January 1990].

By the end of 1989 a serious lead intoxication of cattle occurred in the northern part of the Netherlands (provinces Groningen and Friesland). This intoxication appeared to be caused by contaminated feed. Over 300 farms were stricken, with about 15,500 animals (mostly dairy cattle). In a period of one to four weeks these animals consumed about 1,000 kg of lead. This resulted in lead levels in milk, livers, and kidneys above the regulatory safety limits. Thanks to the chelating therapy that was rapidly applied by the local veterinarians, only about 30 animals died of an acute lead intoxication. The cooperating governmental and private authorities took action to prevent exposure of consumers to lead-contaminated animal products. Based on careful estimations, predictions were made of the lead levels to be expected in animals products and the time needed for depletion of these levels. The appropriate animals were marked to ensure their identification, and the decline in time of the lead levels in milk and offals was conscientiously monitored. In the second week of 1990 the lead concentrations were decreased to levels well below the regulatory limits, and hence the marks were removed from the animals.

Animal Feed↗
PubMedDate not supplied

Lead intoxication in cattle: a case report.

During the autumn of 1989 a feed contamination induced a widespread lead intoxication of cattle in the northern provinces of The Netherlands (Groningen and Friesland). Over 300 farms were involved, affecting about 15,500 animals (mostly dairy cattle). For a period of one to four weeks these animals took up a thousand kg of lead. This resulted in lead levels in milk, livers, and kidneys above the regulatory safety limits. Due to the chelating therapy, which was rapidly applied by the local veterinarians, only about 30 animals died of an acute lead intoxication. A joint action of the governmental and private authorities prevented exposure of consumers to lead-contaminated animal products. Based on observations, measurements and literature data, predictions were made of the lead levels to be expected in animal products and the time needed for depletion of these levels. The appropriate animals were ear-tagged to ensure their identification, and the decline in time of the lead levels in milk and offals was conscientiously monitored. In the second week of 1990 the lead concentrations were decreased to levels well below the regulatory limits, and hence the tags were removed. The present paper reports our observations and conclusions, especially regarding treatment, predictions and outcome of this incident.

Animal Feed↗