Comparison between a new acceleration transducer and a conventional force transducer in the evaluation of twitch responses

An acceleration transducer elicits an output voltage proportional to the deformation of the piezo crystal, in accordance with the twitch responses of the applied fingers. The reliability of such a transducer was evaluated by comparing induced twitch responses with those from a force transducer applied on the contralateral arm of an individual during neuromuscular block with vecuronium. The results obtained from twitch responses with the acceleration transducer during neuromuscular block were almost identical to those obtained with the force transducer. Also, the twitch heights due to acceleration of the examined thumb correlated extremely well with the twitch height due to twitch tension with the force transducer. It is concluded that the acceleration transducer may be a useful and reliable device for monitoring neuromuscular block, although responses during tetanic stimulation such as tetanic fade cannot be determined by the transducer.

Prolonged activation of hypothalamo-pituitary-ovarian axis during early infancy in female patients with salt-losing 21-hydroxylase deficiency

We observed prolonged genital bleeding during the first 2-3 months after treatment in five of 13 female patients with salt-losing 21-hydroxylase deficiency. Their relatively low concentrations of serum follicle-stimulating hormone and luteinizing hormone before therapy increased rapidly to high levels which were maintained for 1-3 wk and then decreased. The duration of these relatively high levels after therapy was longer in the patients with genital bleeding than those without. Before therapy, there was no release of serum follicle-stimulating hormone and luteinizing hormone following the administration of synthetic luteinizing hormone-releasing hormone in two patients; 1 month after therapy, the response to luteinizing hormone-releasing hormone increased significantly. Serum estradiol increased above 300 pg/ml in four patients with genital bleeding but was less than 175 pg/ml in three patients without bleeding. The etiology of genital bleeding in these female patients may be more prolonged activation of the hypothalamo-pituitary-ovarian axis and a greater increase in the responsiveness of internal genitalia to gonadotropins and sex hormones, perhaps induced by prolonged exposure to excessive adrenal steroids starting before birth.

Molecular basis of ornithine transcarbamylase deficiency lacking enzyme protein

We report an ornithine transcarbamylase(OTC)-deficient male patient who had no detectable immunoreactive materials but did have active mRNA for OTC-related protein. The total absence of OTC activity in the liver of the patient was caused by a complete lack of immunoreactive material, as determined by Ouchterlony double immunodiffusion, single radial immunodiffusion, and sodium dodecylsulphate-polyacrylamide gel electrophoresis of immunoprecipitate and of liver homogenate. However, mRNA coding for the precursor of OTC was clearly detected in autopsy specimens of the patient's liver as well as of controls in a cell-free translation system consisting of rabbit reticulocyte lysates and [35S]methionine. The labelled precursor of OTC synthesized in vitro with mRNA from the patient could be transported into rat liver and kidney mitochondria and processed to form a protein with a molecular weight indistinguishable from mature OTC, suggesting that there was no defect in the protein structure necessary for its transport into mitochondria. These results suggest that the primary defect of the OTC deficiency was located in the structural gene and that the labile OTC-related protein, after being synthesized with its mRNA, was degraded too rapidly to be detected by the method used.