The Bergen Blood Pressure Study: Definition of Hypertensive and Normotensive Families Based on 27 Years' Follow-up

The familial aggregation of hypertension is well documented. However, many studies on the familial predisposition have suffered from insufficient knowledge of parental blood pressure (BP). In the present study, the family history is defined according to parental data from two BP surveys conducted almost 30 years apart. Data from a population screening in Bergen in 1963-64 were linked with information on marital status to define couples with or without a history of hypertension. Within the screened population a total of 344 married couples, 688 individuals, matched defined age and BP criteria. Four hundred and thirty individuals, representing 270 of the 344 families initial included (79%), attended a follow-up examination in 1990. Six hundred and ninety-one offspring were registered. In all families represented at follow-up, parental BP data from the 1963-64 screening were available. In 160 families (n_offspring = 393), both parents also attended the follow-up examination in 1990. In 23 families (n_offspring = 54) both parents were hypertensive in 1963-64 as well as in 1990. In 22 families (n_offspring = 55) both parents were normotensive at both examinations. Thus, a family data base which is assumed to be useful for studies on offspring with or without a family history of hypertension, has been established. The offspring studies include BP, 24-h ambulatory BP, electrocardiography, echocardiography, endocrine parameters, electrolytes and anthropometric variables.     

The Bergen Blood Pressure Study: Sodium Intake and Ambulatory Blood Pressure in Offspring of Hypertensive and Normotensive Families

Sodium intake, estimated by the 24-h urine sodium excretion, was assessed in 39 offspring of hypertensive families and 37 offspring of normotensive families. The family history of hypertension or normotension was defined according to parental BP data from two surveys conducted 27 years apart. Urine sodium excretion was similar in offspring of hypertensive and normotensive families, averaging 136 and 137 mmol/24 h, respectively. Monitored by non-invasive methodology in the urine sampling period, the average 24-h ambulatory blood pressure (BP) was approximately 10/10 mmHg higher in offspring of hypertensive than normotensive families. The clinically and statistically significant differences in BP between groups could not be explained by differences in sodium intake. After adjustment for confounding variables, the BP was not associated with the sodium excretion in the material as a whole or in either offspring group.     

Mercury in primary teeth in preindustrial Norway

Seventy-nine primary (deciduous) teeth were excavated in 1978 underneath the floor of the stave church in Uvdal, Buskerud County, Norway. The mercury content of 57 teeth was measured by means of cold vapor atomic absorption spectrophotometry. As a comparison, 124 primary teeth from modern Norway were analyzed. A significant statistical difference was found between the two sets of material. In the Uvdal material a correlation was found between the mercury and copper contents. For the modern material a correlation was found between mercury and lead, and between mercury and zinc. The authors maintain that the values found for the Uvdal material represent base-line values for mercury in primary teeth, and probably reflect uptake from natural environmental sources only. Furthermore, these values may be used for reference in studies of other preindustrial, as well as modern, primary teeth. Our findings also indicate a higher level of mercury in modern than in preindustrial primary teeth in Norway.     

Major and minor form of hereditary hyperekplexia.

Hyperekplexia is a hereditary neurological disorder characterized by excessive startle responses. Within the disorder two clinical forms can be distinguished. The major form is characterized by continuous generalized stiffness in the first year of life and an exaggerated startle reflex, accompanied by temporary generalized stiffness and falls, whereas in the minor form only excessive startle and hypnic jerks have been described. Mutations in the gene encoding the alpha-1 subunit of the glycine receptor (GLRA1) are responsible for the major form of hyperekplexia but no mutation was detected in patients with the minor form in the large Dutch pedigree originally described by Suhren and colleagues. Here we describe the genetic analysis of the GLRA1 gene of two English families in which both forms of hyperekplexia were present. Mutation analysis revealed no genetic defect in the GLRA1 gene in patients carrying either the minor or major forms. This is further evidence that the minor form of hyperekplexia is seldom due to a genetic defect in the GLRA1 gene.     

Ultrastructure of adult and juvenile marmoset (Callithrix jacchus) Sertoli cells in vivo and in vitro.

The morphologic differentiation of Sertoli cells isolated from adult and juvenile marmosets and cultured on different extracellular matrices was evaluated by light and electron microscopy and compared to cells in vivo. Both cell types could be maintained in culture for at least 6 days. The degree of cellular differentiation, shape, ultrastructural appearance, and polarity seemed to benefit from laminin-coated substrata, compared with collagen-, fibronectin-, serum-, and heparan sulfate-coated substrata. With the former two substrates, a difference in behavior between juvenile and adult cells was evident. Whereas juvenile cells displayed a lesser degree of differentiation, adult cells exhibited identical morphologic characteristics in culture and in vivo. Cyclicity of morphologic features was not found, neither in vivo nor in vitro. The results indicate that: (1) laminin plays a unique role for marmoset Sertoli cell differentiation in vitro compared with other extracellular components; (2) a greater similarity between cells in vivo and in vitro is evident with adult Sertoli cells; and (3) the adult marmoset monkey could provide a primate model for mature Sertoli cells in culture, since there is a close similarity to human adult Sertoli cells in vitro and in vivo.     

Comparison of the Mitogenic Activities of Streptococcal Protein-G and Staphylococcal Protein-A on Human Mononuclear Cells

In the present work we report data from experiments comparing the proliferative stimuli demonstrated by Streptococcal Protein-G and Staphylococcal Protein A on human peripheral blood mononuclear cells. Protein-G and Protein-A are presented to the cells in solution as well as linked to plastic or Sepharose beads, or incorporated within the cell wall of whole bacteria. The cellular response is measured by incorporation of 3H-thymidine in 72 hr cultures.

The soluble and the immobilized forms of Protein-A, but not those of Protein-G, displayed high mitogenicity. Possible explanations for the absence of Protein-G induced mitogenicity are discussed.