Developmental toxicity potential of grayanotoxin I in mice and chicks

Developmental toxicity potential of grayanotoxin I (GTX I), a toxic diterpenoid contained in plants of the family Ericaceae, with sodium ionophore activity, was studied in mice and chicks. In mice, intraperitoneal injections of 1.5 mg GTX I/kg body weight of mouse for three consecutive days during the organogenetic period caused some dams to die, but neither embryotoxicity nor teratogenicity was detected. In chicks, a single injection of 0.1-1.0 microgram GTX I per egg into the extraembryonic coelom on day 1.5 or 2 of incubation, or into the amnionic cavity on day 3 or 4 of incubation induced neither embryotoxic nor teratogenic signs, but 10 micrograms GTX I per egg showed lethal effects when applied on each of those days.     

SPECTRUM OF THYROID FUNCTION ABNORMALITIES IN GESTATIONAL TROPHOBLASTIC NEOPLASIA

The relative influences of the putative thyroid stimulator, pregnancy state and non-thyroidal illnesses, were assessed in 52 patients with gestational trophoblastic neoplasia (GTN). In this study biochemical thyroid status was assessed with the aid of thyrotrophin (TSH) measurements by a sensitive immunoradiometric assay and measurement of total and free thyroid hormone concentrations. The reference group consisted of 63 patients with normal pregnancy. Thyroid function in the GTN patients was also compared with that in 36 female patients with Graves' disease and 34 female patients with non-thyroidal illnesses. We found the major influence on thyroid functions in Group I ('Hyperthyroid') patients with GTN to be the presence of the thyroid stimulator, while non-thyroidal illnesses played an important role in Group II ('High T4 syndrome') and III ('euthyroid') patients with GTN. Thyroid function was also stimulated in Group II patients. The influence of pregnancy was seen in all three groups of patients with GTN, who had higher TBG concentrations than non-pregnant patients. We conclude that there is a spectrum of thyroid function abnormalities in GTN, and that thyroid function in an individual patient is determined by the relative influence of the thyroid stimulator, non-thyroidal illnesses and the pregnancy.     

A comparison of betaxolol and timolol in open angle glaucoma and ocular hypertension

In a randomized, double-masked study, 41 patients with primary open-angle glaucoma or ocular hypertension were treated with betaxolol 0.5% or timolol 0.5% drops for 26 weeks. The average decrease in intraocular pressure (IOP) over the total study period was significant with both betaxolol (-6.3 mmHg) and timolol (-7.2 mmHg) in patients receiving no adjunctive therapy. There was no difference between betaxolol and timolol with respect to changes from baseline IOP. Significantly decreased mean brachial arterial pressure (MAP) was seen only with timolol, although the difference between the two groups was not significant. Pulse, pupil size, and basal tear secretion were unchanged in both groups. Burning upon instillation of the drops was more frequent with betaxolol.     

Method for quantification of brain, ventricular, and subarachnoid CSF volumes from MR images.

We describe a simple, rapid, and semiautomated method of MR analysis based on mathematical modeling of MR pixel intensity histograms. The method is shown to be accurate and reliable for regional analysis of brain, central, and subarachnoid CSF volumes. Application of the method to five young and six older subjects revealed significant age-related changes in regional brain volumes whereas no difference was found for traced central CSF volumes or subarachnoid CSF volumes. We conclude that this is a simple method that can be applied to further studies of quantification of brain structure in healthy aging and brain disease.