Measurement of lymphocyte proliferation: critical analysis of radioactive and photometric methods.

Different methods of lymphocyte proliferation are compared to identify a non-radioactive alternative to 3H-thymidine-test. The enzymatic assays evaluating the turnover of mitochondrial dehydrogenases (MTT-test) and lysosomal hexosaminidase (NAG-test) proved not sensitive enough to substitute for 3H-thymidine incorporation. The incorporation of the nucleotide analog 5-bromodeoxyuridine (BrdU) can be exploited using an ELISA-system (enzyme linked immunosorbent assay) employing a monoclonal anti-BrdU antibody to measure cell proliferation. An optimized test protocol of the BrdU-ELISA which fulfills the requirements for a sensitive and practicable non-radioactive alternative to 3H-thymidine-test is presented.

Effect of oestrogen/gestagen replacement therapy on liver enzymes in patients with Ullrich-Turner syndrome.

The absence of breast development and the prevention of osteoporosis in Ullrich-Turner syndrome (UTS) require oestrogen/gestagen substitution therapy. In 8 out of 35 (23%) patients with UTS treated with conjugated equine oestrogens and cyclically with norethisterone acetate, the serum liver enzymes increased to conspicuous levels (AST 35; 20-73 U/l, ALT 92; 37-141 U/l, GGT 77; 25-227 U/l, [median; min-max]). These findings were compared with those in 41 tall girls who received a six-fold larger dose of conjugated equine oestrogens for the reduction of final height. None of these 41 girls showed abnormal serum liver enzyme levels. The conspicuous rise in serum liver enzyme levels occurred in the majority of the UTS patients before norethistherone acetate was added to the oestrogen replacement therapy. No essential morphological equivalent was found in liver sonography and biopsy studies. During the follow up the elevated serum liver enzyme levels showed reversibility when medication was temporarily discontinued and either a slow decrease or a steady state after therapy was continued. CONCLUSION. Patients with UTS on oral oestrogen replacement therapy are more susceptible to develop increased serum liver enzyme levels as compared with eukaryotic females treated with the same oestrogen preparation for other disorders. As the underlying pathomechanism is unknown and adverse long-term effects cannot be ruled out, avoiding the portal vein and using the transdermal application of oestrogen may represent a viable solution to the problem.

[Long-term follow-up of a boy with recurrent hypoglycemia and cholestasis in congenital growth hormone deficiency]. / Langzeitbeobachtung eines Knaben mit rezidivierenden Hypoglykämien und Cholestase bei angeborenem Wachstumshormonmangel.

We report on a four-year-old boy with congenital growth hormone deficiency who first presented at age 13 weeks with jaundice and recurrent hypoglycemia. Growth hormone deficiency was diagnosed two years later, after cholestasis and hypoglycemia had almost completely disappeared, but length deficiency became apparent. The reason for the association of cholestasis with growth hormone deficiency remains unexplained. Cholestasis can, especially in combination with hypoglycemia, be a first sign of congenital growth hormone deficiency.

Phenotypic variability in patients with generalised resistance to thyroid hormone.

Genetic linkage of generalised resistance to thyroid hormone (GRTH) to the human thyroid receptor beta 1 gene has been identified. To date 38 different mutations in several kindreds have been documented. We report on a family with GRTH displaying an adenine for guanine substitution at nucleotide 1234 resulting in a threonine for alanine substitution at codon 317 of exon 9. This mutation has been described for different phenotypes, suggesting that the heterogeneity in GRTH may be the result of multiple genetic factors.

[The differentiation between premature thelarche and pubertas praecox on the basis of clinical, hormonal and radiological findings]. / Differenzierung zwischen prämaturer Thelarche und Pubertas praecox anhand klinischer, hormoneller und radiologischer Befunde.

In a retrospective study of 39 girls (aged 10 months to 7 10/12 years) with premature breast development criteria for distinguishing between premature thelarche and precocious puberty were analysed. Serum estradiol levels and bone age were determined and a test with luteinizing hormone-releasing hormone (LHRH) performed (inclusion criteria). On the basis of the LHRH test and bone age, premature thelarche was diagnosed in 29 patients and precocious puberty in ten: while those with premature thelarche had a follicle-stimulating hormone (FSH) pattern of rise, in those with precocious puberty the rise in gonadotropin was of the LH type. The LH/FSH ratio 30 min after stimulation was < 1 (median 0.15 [0.03-0.34] in patients with premature thelarche, but > 1 (median 2.1 [1.34-5.67] in those with precocious puberty. Bone age was accelerated by at least 18 months in those with precocious puberty, but it corresponded to their chronological age or was only slightly accelerated in those with premature thelarche. These data thus indicate that premature thelarche and central precocious puberty can be reliably distinguished by the LHRH test and bone age.

New point mutation (R243W) in the hormone binding domain of the c-erbA beta 1 gene in a family with generalized resistance to thyroid hormone.

Two years after the first mutation on exon 7 in the carboxy-terminal part of the hinge domain (D) was reported (Behr and Loos 1992), we have identified the second mutation on exon 7 in patients with GRTH. Interestingly, our mutation it is not located in the two previously described "hot spot regions", but instead very close to the hinge domain (D) of the receptor protein that is essential for the function of the hormone binding domain (E) (Lin et al., 1991). Confirming the observation that the majority of single base substitutions causing human genetic diseases or DNA polymorphisms follow the hot spot mutation rule of CG to TG and CG to CA transition (Barker et al., 1984), an additional CpG dinucleotide transition has been identified.