Transmission electron microscopy of early microbial colonization of human enamel and root surfaces in vivo

Abstract – This study describes the early microbial colomization of teeth by the use of light-and transmission electron microscopy. Six dental students carried a total of 60 test pieces of unerupted enamel and root surface in intraoral acrylic appliances for 4, 8, 12, 24 and 48 h, during which periods oral hygiene was abandoned. Pronounced variations were recorded in structure and thickness of the pellicle across the individual surfaces of both dental tissues. Bacterial single-cell colonization increased the electron density of the adjoining pellicle. Micro-colonies of bacteria were observed in relation to enamel surface irregularities such as perikymata, while the distribution on root surfaces appeared incidental. Root surfaces were generally colonized by thicker deposits than homologous enamel surfaces although the structural composition of the microbiota was similar. Gram-positive bacteria with thick cell walls appeared in coccoid or rod-shaped configurations depending on the age of the bacterial deposit. These bacteria were further characterized by selective invasion between collagen fibers. After 48 h the complexity of the microbiota was increased by the establishment of new bacterial species in the superficial layer. It is concluded that the pattern and composition of the early microbiota on teeth is more complex and variable than hitherto assumed.     

HYPERTHYROIDISM DUE TO A THYROTROPHIN-SECRETING MICROADENOMA

We report a 63-year-old female with a TSH-secreting pituitary adenoma causing hyperthyroidism. This case is apparently unique, and challenges the present concept of dividing patients with inappropriate TSH secretion into tumour and non-tumour groups on the basis of conventional pituitary fossa radiology.     

Sibling sex ratio of individuals diagnosed with autism spectrum disorder as children

Aim To study the sex ratio (proportion of males) in siblings of individuals diagnosed with autism spectrum disorders (ASDs) as children. Method In the current study, we extended previous studies dealing with the androgen theory of autism and examined sex ratios in the siblings of 326 individuals with ASD (245 males, 81 females) who had been consecutively assessed at two Danish university clinics of child psychiatry during the 25‐year period from 1960 to 1985. Results Among the 513 siblings, 300 were males and 213 females. This yields a sex ratio of 0.585, which is significantly higher than the Danish live‐birth sex ratio over the same period (0.514, p=0.001). The sibling sex ratio was not associated with the IQ in the autistic probands. Interpretation Our findings suggest a potential indirect confirmation of the androgen theory of autism.     

HOW TO EVALUATE CLINICAL PARAMETERS AT A GLANCE

Schiøtz, P.O., Beck, B. and Pedersen, M. (Paediatric Department TG, Rigshospitalet, Copenhagen, Denmark). How to evaluate clinical parameters at a glance. Acta Paediatr Scand 1982; suppl 301: 121-124. — A brief introduction is given to the practical approach in cystic fibrosis patient care, which is used at the Danish Cystic Fibrosis centre employing Dr. Flensborg's flowsheets.     

Redistribution of granulocytes during adrenaline infusion and following administration of Cortisol in healthy volunteers

Major surgical procedures induce an endocrine metabolic stress response characterized by increased secretion of adrenaline and Cortisol. Furthermore, surgical stress is accompanied by granulocytosis in peripheral blood. The granulocytosis may be due to increased adrenaline and Cortisol secretion. The purpose of this study was to investigate the redistribution of granulocytes during adrenaline infusion and following administration of Cortisol. Granulocytes were isolated from peripheral blood from eight healthy volunteers, labelled with indium–111–tropolene and reinjected. The distribution of granulocytes was imaged by using a gamma camera and calculated with an interfaced computer three times during a control period and three times during a corresponding hour af adrenaline infusion 0.05 μg kg b.w.^-1 min^-1. The distribution was then measured every second h for another 6–h control period and then for 6 h following administration of Cortisol 3.6 mg kg b.w.^-1 Infusion of adrenaline resulted in granulocytosis in peripheral blood and a reduction of radioactivity of the spleen to 83.0% of the initial value. The effect of adrenaline on the bone marrow was negligible. Cortisol administration was followed by granulocytosis and decreased radioactivity of both the spleen (81.5%) and the bone marrow (79.8%). It is concluded that the spleen is an active immunological organ as both adrenaline and Cortisol induces efflux of granulocytes from the spleen. The Cortisol induced efflux of granulocytes from the bone marrow explains that granulocytosis also occurs in splenectomized patients after major surgery.     

Social characteristics of urban cafe guests in Norway

Which factors may influence the number of hours spent per week in cafes, and the amount of alcohol consumed in licensed premises, by urban cafe guests in Norway? In 1991 a comprehensive questionnaire survey was undertaken among 1053 visitors to 41 licensed cafes in Oslo, Norway. The five most important predictors of time spent in cafes were: household situation (β=0.20), occupation (β= 0.18), personal economic resources and sex (both β= 0.15) and age (β= 0.11). These factors were also significant predictors of the number of days during the past 4 weeks the respondents had drunk jour glasses or more of alcohol in cafes. Men, people living with others, people with poor economic resources and people not engaged in paid employment or education were the ones who reported spending the most hours per week and the most episodes of “heavy” drinking in cafes during a 4-week period. Visiting and drinking in cafes may be a way of structuring everyday life.     

GROWTH, BODY WEIGHT AND INSULIN REQUIREMENT IN DIABETIC CHILDREN

ABSTRACT. The weight and height development of 51 boys and 48 girls who had developed diabetes prior to the age of 15 years was followed for a minimum of 3 years, mean 8.3 years, up to the age of 18 for the girls and 20 for the boys. In addition, the insulin requirements were recorded. Weight and height proved to be within the normal range, and height at onset of diabetes was normal. After a long duration of diabetes, however, there occurred a reduction of height increment of about 1/2 cm/year. This reduction was greater in children who rarely attended as compared with those who frequently attended a sub-specialized clinic. The daily dose of insulin increased with age, the greatest increase coinciding with the growth spurt. During the first 4 years of diabetes the 24-hour dose/kg body weight increased, indicating a decreasing endogenous insulin production. Later it was constant at around 0.9 i.u./kg. Modern management of diabetic children leads to normal adult stature.     

DIFFERENT HEPATIC RESPONSES TO THYROXINE REPLACEMENT IN SPONTANEOUS AND 131I-INDUCED PRIMARY HYPOTHYROIDISM

The serum levels of a range of analytes known to change with thyroid status were measured in two groups of patients with primary hypothyroidism commencing T4 replacement therapy. One group (group 1; n = 9) had spontaneous hypothyroidism whilst in the second (group 2; n = 10), hypothyroidism had resulted from radioiodine therapy. The replacement dose was increased in 50 micrograms increments each month to 200 micrograms/day; this produced similar serum concentrations of thyroid hormones and TSH in the two groups at each dose. Dose-dependent increases in glutathione S-transferase (GST) were seen in both groups but changes in alanine aminotransferase (ALT) and gamma glutamyltransferase (GGT) activities occurred only in group 1 patients. Group 1 patients had significantly higher levels of GST than group 2 at the 150 micrograms (P less than 0.01) and the 200 micrograms (P less than 0.005) doses of T4, and they had higher activities of ALT (P less than 0.01) and GGT (P less than 0.02) at the 200 micrograms dose. Seven patients in group 1 had abnormalities in GST and four had high levels of ALT, whereas three patients from group 2 had high GST concentrations and all had ALT activities within reference limits. The concentrations of the other analytes measured in serum showed the same response to T4 in the two groups, particularly the concentrations of certain transport proteins whose serum concentrations depend on hepatic protein synthesis. These data suggest that patients with spontaneous primary hypothyroidism are more susceptible to hepatocellular damage than patients who have radioiodine-induced primary hypothyroidism when given oral doses of thyroxine greater than 150 micrograms/day.     

END-ORGAN RESPONSES TO THYROXINE THERAPY IN SUBCLINICAL HYPOTHYROIDISM

We studied variables known to change with thyroid hormone status in 18 patients with subclinical hypothyroidism before and during treatment with thyroxine in a dose sufficient to restore the plasma TSH response to TRH to normal. There was an associated increase in both plasma total T4 and free T4 within the normal range but plasma total T3 and free T3 were unchanged. As a result of thyroxine treatment there was a small but significant increase (P less than 0.05) in left ventricular ejection fraction (LVEF) with maximal exercise but no significant changes in LVEF at rest and moderate exercise, continuously monitored mean sleeping heart rate, day/night ratios of urinary sodium excretion, peripheral nerve conduction velocities, fasting serum triglycerides, total cholesterol (TC), high density lipoproteins (HDL) or TC/HDL ratios. On this evidence we do not consider that thyroxine replacement therapy is indicated in patients with subclinical hypothyroidism.