How Do Schoolchildren View Other Children Who Have Discolored Teeth?

Objectives:

Facial look and expression affect how people are viewed by others. This study aimed to evaluate how schoolchildren in the Emirate of Sharjah, United Arab Emirates view their peers who have discolored teeth.

Materials and Methods:

A cross-sectional study using randomized cluster sampling of Sharjah public schools was conducted. A previously developed and validated social attribute questionnaire was utilized to determine children’s dental appearance-related judgments. Children aged 11–14 years were given photographs of subjects either with discolored teeth or without, and they were asked to rate them using six positive and five negative signifiers. The total attribute score (TAS) ranged from 11 (most negative) to 44 (most positive). A linear regression analysis and t-tests were performed to determine the effects of gender and age in mean TAS.

Results:

TAS was significantly lower among discolored teeth photographs when compared with photographs without teeth discoloration (P = 0.004). TAS was found to be significantly higher with increased age (P = 0.035), but gender had no significant effect.

Conclusion:

Teeth discoloration resulted in more negative social judgment between Sharjah schoolchildren and their peers.

Effect of magnesium pyridoxal 5-phosphate glutamate on vascular reactivity in experimental hypercholesterolemia

Hypercholesterolemia is known to affect the responsiveness of various blood vessels to endogenous and to exogenous vasoactive agents. Of particular interest is the increased responsiveness to vasoconstrictors, e.g., 5-hydroxy tryptamine and noradrenaline, and the decreased reactivity towards vasodilators, e.g., acetylcholine. This, together with the development of arteriosclerosis, could play an important role in the progression of many vascular complications, such as hypertension and coronary heart disease. Magnesium pyridoxal 5-phosphate glutamate (MPPG) has been shown to effectively reduce serum lipids in animals and in man, and to retard the progression of atherosclerotic lesions in experimental animals. It was therefore considered of interest to investigate the reactivity of both the aorta and the renal artery to different vasoactive substances in hypercholesterolemic rabbits under the influence of MPPG as well as the effect of such substances on the blood pressure of the anesthetized animals. The rabbits were fed a high cholesterol diet for 2 months, followed by MPPG for 1 month, while keeping the rabbits on the same diet. One batch of animals was used for blood pressure recording and testing drug effects, and another was used for testing the responsiveness of their aortae and renal arteries to the different mediators. In hypercholesterolemic rabbits, treatment with MPPG tended to normalize the increased responsiveness of the blood pressure to the vasoconstrictors: noradrenaline and angiotensin and the diminished sensitivity to histamine and acetylcholine. For the isolated arteries, however, MPPG did not significantly affect the responses to noradrenaline nor potassium chloride, but tended to normalize responses to clonidine and acetylcholine. It could be concluded from the present findings that the high cholesterol diet induces changes in vascular reactivity which are possibly related to endothelial and/or receptor sensitivity changes. Treatment with MPPG helps to reverse these changes and to restore normal vascular reactivity, a fact that could have important clinical implications in the management of cardiovascular diseases.

Effects of vasopressin on the coronary circulation: reserve and regulation during ischemia

In 18 dogs, intracoronary infusion of vasopressin produced a 40% reduction in coronary flow without significantly affecting systemic hemodynamics. The blood flow reduction occurred in a uniform transmural pattern without evidence of a gradient. The reduction in coronary flow resulted in a decrease in regional contractility as determined by isometric strain gauge arches. The decrease in regional contractility was transiently reversed by bolus injection of adenosine into the perfusion line. This suggests that the reduction of blood flow due to vasopressin was causing ischemia. Evidence for ischemia was also supported by measurements of local vein and tissue lactate production. Despite the apparently ischemic conditions, the vascular bed demonstrated evidence for significant reserve and regulation. Pressure-flow relationships performed under control and during vasopressin infusion demonstrated that the coronary vasculature retained its ability to regulate or defend a given level of coronary flow over a range of coronary perfusion pressures. Vasopressin produced a mild decrease in the peak hyperemic flow after a 15-s coronary occlusion and shortened the duration of reactive hyperemia. These overall findings are compatible with a predominant vasoconstrictor effect on the distal coronary vasculature. A role for a myogenic factor in the control of the coronary circulation is suggested, which is amplified by vasopressin.

Chronic manganism: preliminary observations on glucose tolerance and serum proteins

An intravenous glucose tolerance test was carried out in 11 patients with chronic manganese poisoning. Prolonged reactionary hypoglycaemia was observed. The underlying mechanism is discussed. It may be due to a disturbance of the hypothalamo-pituitary-adrenal axis. In seven of these patients total serum proteins were estimated and were separated electrophoretically. The albumin: globulin ratios were lower in patients than in controls. There were significant reductions in serum albumin concentrations and increases in concentrations of α₁ and β globulins.