Effects of Metoprolol on the Counter-regulation and Recognition of Prolonged Hypoglycemia in Insulin-dependent Diabetics

ABSTRACT. The effect of metoprolol on the counter-regulation of prolonged hypoglycemia was studied in eight insulin-dependent diabetics. Insulin was given as an i.v. infusion of 2.4 U/h over 180 min alone, or together with metoprolol (3.0 mg i.v. bolus followed by an i.v. infusion of 4.8 mg/h) in random order. Blood glucose, counter-regulatory hormones, hypoglycemic symptoms and the cardiovascular responses were assayed over 240 min. Metoprolol did not significantly modify the blood glucose levels. The plasma levels of free insulin, however, were elevated by approximately 20% (p<0.01) by metoprolol during hypoglycemia and the plasma concentrations of epinephrine, norepinephrine, growth hormone and cortisol were enhanced by the drug. Sweating was increased by metoprolol, while other symptoms were unaltered. We conclude that metoprolol administered acutely does not aggravate prolonged hypoglycemia in diabetics with blunted response of glucagon. Moreover, exaggerated responses of counter-regulatory hormones, provoked by metoprolol, may compensate for the inhibitory effect of this drug on insulin clearance.     

Capillary supply and muscle fibre types in patients with intermittent claudication: relationships between morphology and metabolism

Abstract. There have been previous reports on an increased oxidative capacity in muscle tissue from the diseased legs of patients with intermittent claudication. The present study was designed to correlate metabolic and morphological data and to investigate whether the metabolic adaptive changes in muscle tissue of claudicating legs were also reflected in morphological variables such as capillary supply, fibre type distribution, and fibre area. The activity of cytochro-me-c-oxidase in gastrocnemius muscle was determined and the insulin and glucose uptakes were measured across the leg in the basal state and 10 min following intravenous administration of 25 g glucose. The finding of a reduced relative number of Type II B fibres and a reduced ratio Type II B/II A fibre area, as well as an increased capillary supply to Type II A, indicated that the most extensive morphologic changes in muscle tissue of claudicating legs had occurred in Type II fibres. The increased number of capillaries in contact with Type IIA fibres in muscle tissue from claudicating legs, compared with muscle tissue from control legs, suggested that the most apparent metabolic changes occurred in this fibre type in the adaptation process of these patients. The more pronounced morphologic and metabolic changes in Type II fibres suggest that these fibres are more intensely activated than Type I fibres during physical activity in claudicating legs. The insulin uptake correlated positively with the number of capillaries per fibre, suggesting that the endothelial surface area is one of the determining factors for insulin uptake. The percentage of Type II B fibres reflected to a certain extent the metabolic adaptation in muscle tissue.     

Histochemical studies on cholesterol formation in odontogenic cysts and granulomas

abstract — A histologic and histochemical study was made of 45 odontogenic periapical cysts and granulomas with cholesterol formation. The specimens were transported in Histocon® solution and sectioned by cold microtome. This technique permits the preservation of the lipids and rertains the enzyme activities in the cells. Cholesterol crystals seemed to be formed in disintegrating clots of red blood corpuscles in congested capillaries of the inflammatory areas. The pericytes of the vessel walls changed their enzyme activities, indicating increased lysosomal functions, and eventually formed giant cells with tissue degrading properties.     

Dental root translucency as an indicator of age

Abstract – The apical translucent zone was studied in 1000 human teeth. For each type of tooth, excluding molars, the size of the apical translucency was estimated according to the scoring methods of G ustafson (I), D alitz (2) & J ohanson (3). The lengths of the translucent zones were measured on moist and then on dry teeth, both unsectioned and sectioned, while the areas were measured on dry sectioned teeth only. Statistical analyses using the SPSS package in a Cyber computer indicated a symmetric distribution of the translucent zone in left and right teeth. The extent of the translucency showed little variation from one type of tooth to another. The length of the translucent zone measured on unsectioned teeth demonstrated in most types the closest relation to age. Multiple regression analyses, including more than one method of measuring the size of the translucent zone, resulted in formulas showing a high correlation with age (from 0.68 to 0.86). Slightly larger translucent areas were found in teeth from males, in darker teeth and in teeth with increased thickness of the cementum. The increase in the translucent zone with advancing age was found to be almost linear and was not affected by periodontal destruction.     

Light and transmission-electron microscopy study of enamel organ cells in germectomized human third mandibular molars

Abstract— Using nine serially sectioned germectomized mandibular third molars it was possible to examine light microscopical (LM) and transmission-electron microscopical (TEM) features of maturing human enamel organ cells. The degree of enamel mineralization was estimated by quantitative imbibition studies in polarized light. It was possible to distinguish between three progressive stages of enamel mineralization. The most advanced stage was characterized by external enamel porosity. In the least advanced stages the enamel porosity appeared more extensive beneath a less porous surface layer. Ruffle- and smooth-ended ameloblasts were identified corresponding to the maturing enamel. Smooth-ended ameloblasts were the most frequently observed. However, no preferences for one of the two cell types could be observed in relation to the different stages of enamel mineralization. The maturing human enamel organ cells broadly revealed the same characteristics with respect to morphology features, intracellular organization, and junctional complexes as described in the maturation zone of the rat incisor enamel organ. Our findings therefore add to the view that the basic pattern of amelogenesis is identical in human and rat incisor enamel.     

Juvenile Diabetes Mellitus—a Risk Factor for Postoperative Venous Thromboembolism?

ABSTRACT In a retrospective analysis of 125 patients and a prospective evaluation of 83 patients with terminal uremia undergoing kidney transplantation, juvenile diabetes mellitus was found to be a significant risk factor for the development of postoperative thromboembolism. We found a high frequency of objectively verified thromboembolism despite the relatively young age of the patients. Besides diabetes, no other clinical risk factor differed between patients with and without thrombosis.     

A study of the occurrence of symptons of disease of the temporomandibular joint masticatory musculature and related structures

An examination of the temporomandibular joints, masticatory musculature and related structures was made on 1069 persons working in a ship-building yard in the south of Sweden. One-fifth of the persons reported that they had frequent headache and one-fourth of the persons reported TMJ-sounds. Clinical examination of the temporomandibular joints and masticatory musculature showed that clicking of the TMJ was the most common symptom (65%) followed by tenderness of the masticatory musculature to palpation (37%) and tenderness of the temporomandibular joint (10%). Thirty per cent of the persons examined reported two or more of these symptoms. Severe abrasion was noted in 12%. The results of the investigation suggested that the frequency of diseases related to function of the masticatory system is high. It was estimated that some 25–30% of the persons examined were in need of treatment.