Growth hormone (hGH) reserve following arginine administration and the paradoxical hGH response to thyrotropin-releasing hormone (TRH) were studied in 30 diabetics without evidence of vascular complications. The diabetics were divided into 4 groups according to the type of their disease and to the metabolic condition within the IDDM group (insulin-dependent: IDDM, in acceptable response and in poor metabolic control; non-insulin-dependent: NIDDM, and juvenile diabetics not requiring insulin at least for two years after diagnosing their disease: NIDDY). The results were compared with controls of identical age and normal weight. A paradoxical hGH response to TRH stimulation was found only in IDDM patients in poor metabolic control. In this group the hGH reserve revealed by arginine was significantly larger than in the others. It was shown that the induced hGH release was independent of the sex distribution of the groups and of the basal hGH values. Magnitude of the hGH reserve and appearance of the paradoxical hGH response were not necessarily correlated but the substantial reserve was frequently associated with a paradoxical response. It can be assumed that the unfavorable metabolic condition is of decisive importance in giving rise to these anomalies. Our observations seem to confirm the need for good metabolic control if the pathological hGH secretion in diabetics is to be prevented.

Adult↗

PubMedDate not supplied

A critical review of experimental data for the half-lives of the uranium isotopes 238U and 235U.

The existing experimental data for the half-lives of the uranium isotopes 238U and 235U have been scrutinised in detail because of their significant practical importance, in particular for geochronogical use and for the assay of standard samples used for neutron fluence and cross-section measurements. The most accurate measurements by Jaffey et al. (Phys. Rev. C 4 (5) 1889) with 1sigma uncertainties of 0.054% (238U) and 0.068% (235U), are not confirmed by other measurements of comparable accuracy. In this work, we take a critical look at the 238U and 235U half-life measurements in the literature. Although we find that the Jaffey et al. data are concordant with other reliable results, generally much higher uncertainties of the latter cannot prove or disprove the Jaffey et al. results. Therefore, at this time, we do not recommend new half-life values. Instead, we call for new measurements of these two half-lives with accuracies comparable to the work of Jaffey et al.

Half-Life↗

PubMedDate not supplied

Colorimetric assay of HIV-1 proteinase suitable for high-capacity screening.

The cleavage of substrate peptides by HIV-1 proteinase can be monitored by reaction of exposed amino groups with 2,4,6-trinitrobenzenesulfonic acid to yield yellow-colored products. This method provides a high-capacity assay of the enzyme which can be performed on microtiter plates.

Amino Acid Sequence↗