Tongue pressure production during swallowing in patients with mandibular prognathism.

UNLABELLED: Abnormalities of swallowing in patients with mandibular prognathism have not been evaluated quantitatively. The aim of this study was to compare tongue pressure production for bolus transfer between volunteers with normal occlusion and patients with mandibular prognathism. The control group had 10 female volunteers with normal occlusion, and the patient group had 10 women with mandibular prognathism. Tongue pressure was measured by a palatal sensor sheet at five sites on swallowing 4 mL of a tasteless and odourless jelly. RESULTS: The tongue pressure waveform differed between the control and patient groups. The incidence of a double-peak tongue pressure waveform was more frequent in the patient group. In both groups, the exertion of tongue pressure began at the anterior point of the sensor sheet, followed by the peripheral parts. Although the order of expression of tongue pressure was the same for the two groups, maximum tongue pressure at all parts of the sensor sheet was lower in the patient group than in the control group. Furthermore, swallowing time was longer in the patient group than in the control group at the peripheral parts of the palate. These results clearly show the difference in tongue pressure production during swallowing between patients with mandibular prognathism and volunteers with normal occlusion. The current findings suggest that maxillofacial morphology may affect tongue movement during swallowing.

Hemodynamic response of ovarian artery after hCG injection.

We have analyzed ovarian hemodynamics immediately after human chorionic gonadotropin (hCG) administration in patients treated by clomiphene-hCG and human menopausal gonadotropin-hCG. This study involved 40 infertile women who signed consents to participate in this study. After intramuscular injection of 10000 IU hCG, the change of ovarian arterial blood flow (BF) was evaluated by color Doppler. Pulsatility index, resistance index, maximum velocity (V(max)), mean velocity, minimum velocity, cross-sectional area of ovarian artery (Area) and BF were measured before and 15-180 min after hCG administration. In the 36 subjects in which ovulation was induced successfully, V(max) and BF increased significantly even at 15 min after hCG administration and thereafter. In the 4 non-ovulatory subjects, no significant changes in any of indices at any of measured time points were observed. Comparative study of non-ovulatory and ovulatory subjects suggested that ovulation may be predicted by the ovarian hemodynamic analysis immediately after hCG administration.

Biological interaction between transition metals (Ag, Cd and Hg), selenide/sulfide and selenoprotein P.

The interaction between transition metals (Ag+, Cd2+ and Hg2+) and selenium (Se) in the bloodstream was studied in vitro by means of the HPLC--inductively coupled argon plasma-mass spectrometry (ICP MS) method. Transition metal ions and selenide (produced in vitro from selenite in the presence of glutathione) or sulfide (Na2S) formed a (metal-Se/S) complex, which then bound to a plasma protein, selenoprotein P (Sel P), to form a ternary complex, (metal-Se/S)-Sel P. The molar ratios of metals to Se were 1:1 for Hg/Se and Cd/Se, but either 1:1 or 2:1 for Ag/Se, depending on the ratio of their doses. The results indicate that the interaction between transition metals and Se occurs through the general mechanism, i.e., transition metal ions and selenide form the unit complex (metal-Se)n, and then the complex binds to selenoprotein P to form the ternary complex ¿(metal-Se)n¿m--seleno-protein P in the bloodstream.

Binding sites for the (Hg-Se) complex on selenoprotein P.

The mechanism underlying the interaction between mercury (Hg), selenium (Se) and selenoprotein P (Sel P) in the bloodstream has been explained by the formation of the [(Hg-Se)n]m-Sel P complex. In the present study, the binding sites for the (Hg-Se)n complex on Sel P were studied by competitive assay of the binding of the (Hg-Se)n complex to Sel P with polymeric and monomeric amino acids with simultaneous detection of the Hg, Se of selenite origin and Se of Sel P origin by the high performance liquid chromatography-inductively coupled argon plasma-mass spectrometry method. The specific binding of the (Hg-Se) complex but not Hg2+ or selenide to Sel P was explained by the unique binding sites consisting of the cationic and anionic ends such as imidazolyl and selenol groups on Sel P, respectively. The number, n, in the (Hg-Se)n complex was estimated to be approx. 100, while the number, m, in the [(Hg-Se)n]m-Sel P complex was estimated to be 35. The formation of the unit complex (Hg-Se)100, followed by its binding to Sel P at up to the 35 binding sites on Sel P was suggested.

Binding of endogenous and exogenous cadmium to glutelin in rice grains as studied by HPLC/ICP-MS with use of a stable isotope.

Cadmium (Cd) in polished rice grains was extracted under various conditions and the chemical forms of the metal in soluble fractions were determined together with copper, zinc and other metals by HPLC with on-line detection by inductively coupled argon plasma (ICP)--mass spectrometry (MS). Cd (753 ng/g) in rice grains grown in Cd-contaminated rice fields was mostly bound to glutelin in soluble fractions. Binding of Cd in vitro to constituents in rice grains was examined by incubating CdCl2 enriched with 113Cd (96.3% enrichment) in a suspension of powdered rice grains. Distributions of exogenous 113Cd in the soluble fraction of Cd-contaminated rice grains was identical with that of endogenous Cd on a size-exclusion column, and the metal was shown to bind to glutelin up to 5.0 micrograms/g in the control rice grains, indicating that exogenous Cd can be bound to glutelin up to this capacity. Simultaneous speciation of exogenous 113Cd and endogenous 111Cd was demonstrated to be highly effective for comparing the binding of Cd natural and artificial origins.