Vitamin A Nutrition in the Human Foetus: A Comparison of Sweden and Ethiopia

ABSTRACT. The accumulation of vitamin A during foetal development was investigated post mortem in foetuses and newborn infants of well-defined socio-economic groups of Swedish and Ethiopian women. The median vitamin A concentration in the liver was 37.0 μg/g in the Swedish foetuses (n=39) and 9.1 μg/g in the Ethiopian ones (n=49) (p<0.001). The liver vitamin A concentration in the Swedish foetuses increased exponentially during the second and third trimesters of pregnancy. This trend was not evident in the Ethiopian material. The mean serum concentration of retinol-binding protein was only slightly lower in the healthy Ethiopian newborns (18.6 mg/l; n=70.) than in the Swedish newborns. This finding suggests that vitamin A is retained i the foetal circulation in preference to storage, much like the situation in a vitamin A deficiency state in the adult.     

Two-year assessment of anterior resin restorations inserted with two acid-etch restorative procedures

Abstract Fifty-two pairs of Class III restorations in a microfilled resin Silar were inserted in acid-etched cavities. A bevel preparation was performed along the margin of one cavity (A) whereas the other cavity was treated with the surface-active comonomer NPG-GMA before filling (B). After finishing of the restorations, the surface of the type B filling was re-etched and covered with a layer of non-composite, low-viscous resin. Following a 2-yr observation period 65 restorations were classified as "good", 33 were "adequate" and 4 were "unsatisfactory" or were replaced during the study period. The only significant difference between type A and type B restorations was marginal discolorations which most frequently were observed along the beveled type A restorations. The occurrence of such failures was increased by marginal deficiencies and occlusion/articulation on the restorations.     

Inter- and Intraday Variability in Major Electrocardiogram Intervals and Amplitudes in Healthy Men and Women

DOTA, C.D., et al. : Inter- and Intraday Variability in Major Electrocardiogram Intervals and Amplitudes in Healthy Men and Women. The ECG may vary during the day (intra-day), and between days (interday), for the same subject. Variability in ECG characteristic measurements between different investigators is well documented and is often large. During days 1–6 of each placebo period of a two-way crossover Phase I study, digital ECGs were recorded at about 8 and 12 am in 16 healthy volunteers (8 men, 8 women). Two observers independently analyzed leads V₂ and V₆ using EClysis software. The durations and amplitudes of major ECG waves and the intervals between major electrocardiographic events were analyzed in a mixed model ANOVA, in which subject, observer, time, and day were treated as random factors. The influence of various corrections for heart rate on the variability of QT intervals was investigated. The difference among subjects explained between 44–81% of the total variability in ECG intervals and amplitudes. Overall, inter- and intraday variability was not statistically significant for any variable. The individualized exponential correction of the QT interval for heart rate eliminated the QT interval dependence on the RR interval in all subjects. Changes in T wave morphology and shortening of the QT interval from morning to noon were observed in ten subjects. The interobserver variability was close to zero   (SD < 0.005 ms)   for all variables except the PQ interval (SD 1.4 ms). The various sources of variability in determinations of ECG wave characteristics should be considered in the design of clinical studies. The use of EClysis software for ECG measurements in this study made the results highly observer independent. (PACE 2003; 26[Pt. II]:361–366)     

Glycosaminoglycans of temporomandibular articular discs

abstract — The glycosaminoglycans of the fibrous cartilage of temporomandibular articular discs from rat, rabbit, dog and monkey have been separated by means of cellulose acetate membrane electrophoresis on a micro scale. The total glycosaminoglycan amount present in these tissues was found to be 1.8, 1.8, 1.4 and 1.2 μg uronic acid, respectively, per mg tissue wet weight. Two major glycosaminoglycan fractions with the electrophoretic mobility of hyaluronate and dermatan sulfate were present, with the latter predominating.     

Rate of plaque formation – some clinical and biochemical characteristics of "heavy" and "light" plaque formers

Abstract – The purpose of the present study was to give a clinical arid biochemical characterization of two groups of individuals with different rates of plaque formation. From 133 individuals, 9 "heavy" and 10 "light" plaque formers were selected. The mean plaque index after 3 days of plaque accumulation, on buccal surfaces of premolars and first molars, was 2.6 for the "heavy" and 0.6 for the "light" plaque formers. The following variables, were determined: periodontal status, DFS, dietary habits, salivary secretion rate and buffer effect, S. mutans and lactobacillus counts in saliva, salivary content of IgA, lactoferrin, lactoperoxidase and lysozyme, saliva-induced aggregation of certain oral streptococci, gel electrophoresis of saliva, amino acid composition of saliva and the acquired pellicle and retention depth of the dentogingival area. Comparing the two groups of plaque formers, statistically significant differences were found for the following three variables: parotid saliva-induced aggregation of a strain of S. sanguis, content of glutamic acid in the acquired pellicle and retention depth of the dentogingival area for maxillary premolars. Large variations for all studied variables were found, both within and between the groups. Several factors may be involved in plaque formation and none of the studied variables alone could explain the large difference in the amount of plaque formed after 3 days between the "heavy" and "light" plaque formers.     

UV treatment of uraemic pruritus reduces the vitamin A content of the skin

The effect of phototherapy on uraemic pruritus and vitamin A content in serum and epidermis was investigated in ten patients with chronic renal failure. The patients and five healthy controls were given repeated whole-body irradiation of UV-A + UV-B (total dose 7.9 + 1.3 J cm-2). Serum and skin samples were obtained before and after the treatment. Serum samples were analysed for retinol, retinol-binding protein and carotene and epidermis samples for retinol, 3-dehydroretinol and carotene. Before treatment, the retinol concentrations in serum and epidermis were higher in patients than in controls. The treatment, which relieved seven patients of pruritus, reduced the epidermal retinol from 11.6 +/- 4.5 to 7.0 +/- 3.8 nmol g-1 protein (P less than 0.02). A similar reduction occurred in the controls (4.5 +/- 1.0 v. 1.7 +/- 1.0, P less than 0.01). No changes of epidermal 3-dehydroretinol, carotene or the serum parameters occurred in either patients or controls. The putative relationship between uraemic pruritus and hypervitaminosis A and the response of this condition to UV therapy is discussed.     

Effect of pituitary hormones on dentin production in maxillary incisors in the rat

abstract — The effect of pituitary hormones on dentin production and longitudinal growth of the maxillary incisors in normal and hypophysectomized rats was investigated. Bovine growth hormone was found to increase the dentin production slightly in normal rats and significantly in hypophysectomized rats. Other pituitary hormones showed no effects on dentin apposition in the doses and periods tested. The effects of the pituitary hormones on the longitudinal growth of the tooth were small or insignificant. The effects of growth hormone on the dentin apposition and the longitudinal growth of the tooth after hypophysectomy were smaller than the effects on longitudinal bone growth and cortical hone remodeling, indicating different sensitivity to hormones between different mineralized tissues.     

RENAL FUNCTION AND BIOPSY CHANGES DURING THE COURSE OF HENOCH-SCHÖNLEIN GLOMERULONEPHRITIS

ABSTRACT. Renal function studies were performed in 18 subjects in different stages of Henoch-Schönlein glomerulonephritis (HS GN). Nine children were serially investigated, and nine adolescents or young adults, who were considered to have clinically recovered, were investigated only once, 10.5–14 years after the onset. Inulin and PAH clearance, as well as sodium excretion, were determined during hydropenia (HP) and 3% volume expansion (VE) with isotonic saline. In most patients in the former group a renal biopsy was performed during the first investigation and again one year later. The early disturbances in renal function resembled those we have found in other types of GN. The GFR was normal during HP or after VE in most cases one year after the onset. The natriuretic response to VE was decreased in most patients initially, and this was found to persist in half of the patients 2-3 years after the onset. Pathological urinalyses then indicated disturbances in the renal handling of sodium. A reduced capacity to excrete sodium, however, did not seem to be of prognostic significance since all patients, except one who developed renal insufficiency and hypertension, had normal urinalyses and blood pressure six years after the onset. This study provides no evidence that subjects with previous HS GN will later develop impaired renal function or be predisposed to hypertension.     

Sucking habits and their relation to posterior cross-bite in 4-year-old children

Abstract – Sucking habits and their relationship to posterior cross-bite were studied in 4-year-old children (n = 588) living in the municipality of Huddinge on the outskirts of Stockholm. Previous or persisting sucking habits were registered for 88% of the children with dummy sucking as the dominating type (78%). At the age of 4 years 48% of all children still exhibited some form of sucking habit. The incidence of normal buccolingual occlusion steadily decreased in cases where sucking habits persisted. The increase in unilateral cross-bite occurreoce was most pronounced in cases where the children continued sucking after 2 years of age. The variable "intensity of sucking habit" was significantly correlated to the occurrence of unilateral cross-bite ( P <0.05). From a dental point of view these results indicate that sucking habits in children should be brought under control by 2 years of age.