Showing papers by "University of Gothenburg published in 1995"

Effectiveness of treatment with a brace in girls who have adolescent idiopathic scoliosis. A prospective, controlled study based on data from the Brace Study of the Scoliosis Research Society.

Abstract: In a prospective study by the Scoliosis Research Society, 286 girls who had adolescent idiopathic scoliosis, a thoracic or thoracolumbar curve of 25 to 35 degrees, and a mean age of twelve years and seven months (range, ten to fifteen years) were followed to determine the effect of treatment with observation only (129 patients), an underarm plastic brace (111 patients), and nighttime surface electrical stimulation (forty-six patients). Thirty-nine patients were lost to follow-up, leaving 247 (86 per cent) who were followed until maturity or who were dropped from the study because of failure of the assigned treatment. The end point of failure of treatment was defined as an increase in the curve of at least 6 degrees, from the time of the first roentgenogram, on two consecutive roentgenograms. As determined with use of this end point, treatment with a brace failed in seventeen of the 111 patients; observation only, in fifty-eight of the 129 patients; and electrical stimulation, in twenty-two of the forty-six patients. According to survivorship analysis, treatment with a brace was associated with a success rate of 74 per cent (95 per cent confidence interval, 52 to 84) at four years; observation only, with a success rate of 34 per cent (95 per cent confidence interval, 16 to 49); and electrical stimulation, with a success rate of 33 per cent (95 per cent confidence interval, 12 to 60).(ABSTRACT TRUNCATED AT 250 WORDS)

A histomorphometric and removal torque study of screw-shaped titanium implants with three different surface topographies.

Abstract: Screw-shaped implants with 3 different surface topographies, evidenced visually as well as numerically with an optical profilometer, were inserted in rabbit bone. After a healing period of 12 weeks, a statistically significant higher removal torque was needed to unscrew screws blasted with 25-microns TiO2 particles and screws blasted with 75-microns particles of AI2O3 compared with screws with a turned surface. The histomorphometric evaluation demonstrated a higher percentage of bone-to-metal contact for implants blasted with 25-microns particles of TiO2 compared with the as-machined implants. A greater surface area of bone in threads was found for the turned screws compared with screws blasted with 25-microns TiO2 particles. In the short-term follow-up, there was a better fixation of implants with an average surface roughness of 0.9-1.3-microns and with a homogeneous surface structure than of implants with an average surface roughness of 0.4 microns and with a clear direction of the surface pattern.

Dietary fat and obesity: evidence from epidemiology.

Abstract: The epidemiological evidence that a high-fat diet promotes the development of obesity is considered suggestive but not definitive. The purpose of this paper is to provide a review of various epidemiological methods that have been used to address this issue as well as an updated summary of the existing evidence. Ecological studies describing dietary fat intake and obesity at the population level provide mixed results and are likely to be biased by both confounding and unknown data quality factors that differ systematically across the populations studied. Cross-sectional studies are generally in agreement that the concentration of fat in the diet is positively associated with relative weight. Prospective studies of diet in relation to subsequent weight change give inconsistent results. This may be due to behavioural factors such as dieting in response to weight gain; in addition, this type of study rarely takes into account the possible interaction between genetic predisposition and dietary fat in promoting weight gain. Finally, intervention studies in free-living subjects are considered, providing evidence of a consistent but short-lived period of active weight loss on low-fat diets. The experimental evidence on this relationship is more conclusive than the epidemiological evidence, although biological mechanisms remain controversial. Some areas for future epidemiological research involve: longitudinal studies of dietary fat intake as a predictor of growth in children; observational studies relating total dietary fat and specific types of fat to overall as well as regional adiposity; and randomized intervention studies of the effect of low-fat diets with particular emphasis on and familial predisposition to obesity and other possible modifying factors.

Implant Treatment in Edentulous Maxillae: A 5-year Follow-Up Report on Patients With Different Degrees of Jaw Resorption

Abstract: In a retrospective study, 150 patients with edentulous maxillae were selected for treatment with Branemark implants. The patients were arranged into four different groups, based on jaw shape prior to implant placement. After second-stage surgery, they were provided with either fixed prostheses, removable overdentures followed by fixed prostheses after at least 1 year, or overdentures for the whole period. Patients were followed up for 5 years, with implant and prosthesis survival, annual visits, marginal bone loss, and complications recorded. Results of the study indicated that treatment outcome in edentulous maxillae might be predicted by careful presurgical evaluation of jaw shape. Five-year cumulative implant failure rates varied from 7.9% for patients considered to have enough bone to be provided with fixed prostheses immediately after second-stage surgery to 28.8% for those with severely resorbed jaws receiving an overdenture. The corresponding cumulative prosthesis failure rates were 3.0% and 18.9%, respectively. Patients provided with autogenous bone grafts compared favorably to the group presenting severely resorbed jaws and provided with overdentures, but showed a compromised result compared to the group with the least resorption. Failure of implant treatment correlated significantly with bone quality and ratio of 7-mm implants. All groups, except those treated with bone grafts, showed an average marginal bone level of 1.2 mm after 5 years, irrespective of type of prosthesis. The bone-grafted group showed a corresponding mean level of 2.3 mm after 5 years of function. Regarding clinical complications, a different pattern, mainly related to the type of prosthetic construction used, was observed between the groups. The number of visits clearly indicated that severely resorbed jaws provided with overdentures were the most demanding.

Early Intrathecal Production of Interleukin-6 Predicts the Size of Brain Lesion in Stroke

Abstract: Background and Purpose We have previously demonstrated that stroke influences systemic immune responses. The aim of the present study was to investigate patterns of local inflammatory response as a consequence of acute stroke. Methods Thirty stroke patients were studied prospectively on days 0 to 3, 7 to 9, 21 to 26, and after day 90 with clinical evaluations, radiological assessments, and analysis of serum and cerebrospinal fluid cytokine levels. Results Significantly increased levels of interleukin-6 (IL-6) in cerebrospinal fluid (P<.001) were observed in virtually all patients studied compared with healthy control subjects. This increase was observed during the whole observation period but was significantly more pronounced within the first days after stroke onset, with a peak level on days 2 and 3. This initial increase was significantly correlated (r=.65, P=.002) with the volume of infarct measured by MRI 2 to 3 months later. Serum levels of IL-6 in stroke patients were significantly lower than cerebr...

Assimilation and mobilization of triglycerides in subcutaneous abdominal and femoral adipose tissue in vivo in men: effects of androgens

Abstract: Studies on regional differences of adipose tissue metabolism have mainly been performed in vitro. To allow measurements of lipid uptake in vivo in man, radioactive label from [9,10-3H]oleic acid in 80 g orally administered milk fat was measured after 4 h in abdominal and femoral sc adipose tissues in 28 middle-aged, abdominally obese men. Radioactivity was measured in adipose tissue triglycerides extracted from needle biopsies. Lipoprotein lipase (LPL) activity was also measured. Uptake of label in triglycerides and LPL activity were higher (20% and 15%, respectively; P < 0.05) in the abdominal compared to the femoral adipose tissue region. The men were then randomly assigned to three groups, receiving testosterone (T), dihydrotestosterone, or placebo, for 9 months. After 2 months of treatment, the procedure of administration of label was repeated, this time using [U-14C]oleic acid as a marker. Measurements of radioactive label was then performed after 4 h and monthly up to 7 months. Supplementation with ...

Anchorage of TiO2‐blasted, HA‐coated, and machined implants: An experimental study with rabbits

Abstract: The purpose of this study was to evaluate the histometrical and biomechanical anchorage of TiO2-blasted implants and TiO2-blasted implants coated with hydroxyapatite. The control implants were machined. Twenty-six rabbits had a total of 156 implants placed in the proximal part of the tibia. Each rabbit had a machined, a TiO2-blasted, and a TiO2-blasted, HA-coated implant placed in each tibia. After a healing period of 3 and 12 weeks, respectively, the implants placed in the right tibia were used for removal torque test, and the implants placed in the left tibia were used for histomorphometrical measurements. Preoperatively, implants from the same batches were examined topographically with a TopScan 3D system. The TiO2-blasted implants demonstrated significantly higher removal torque values than the machined implants, and they also had a significantly more irregular surface. Furthermore, significantly higher bone-to-implant contact length fractions were measured adjacent to the TiO2-blasted implants in contrast to the machined implants. The advantages of a TiO2-blasted surface were more pronounced after 3 weeks than after 12 weeks. The results demonstrated that it was possible to influence the anchorage of implants by altering the surface structure morphology. The new method with TiO2 blasting on the titanium surface improves the anchorage of implants but is not yet practicable for HA coating.

Pharmacological correction of neonatal lethal hepatic dysfunction in a murine model of hereditary tyrosinaemia type I.

Abstract: Hereditary tyrosinaemia type I, a severe autosomal recessive metabolic disease, affects the liver and kidneys and is caused by deficiency of fumarylacetoacetate hydrolase (FAH). Mice homozygous for a FAH gene disruption have a neonatal lethal phenotype caused by liver dysfunction and do not represent an adequate model of the human disease. Here we demonstrate that treatment of affected animals with 2-(2-nitro-4-trifluoro-methylbenzyol)-1,3-cyclohexanedione abolished neonatal lethality, corrected liver function and partially normalized the altered expression pattern of hepatic mRNAs. The prolonged lifespan of affected animals resulted in a phenotype analogous to human tyrosinaemia type I including hepatocellular carcinoma. The adult FAH-/- mouse will serve as useful model for studies of the pathophysiology and treatment of hereditary tyrosinaemia type I as well as hepatic cancer.

Child dental fear: cause‐related factors and clinical effects

Abstract: The relationship between child dental fear and clinical effects, and the importance of some etiological factors related to the development of dental fear in children, were studied in 3,204 urban Swedish children aged 4 to 6 and 9 to 11 yr. Information concerning child dental fear (as measured by the Dental Subscale of Children's Fear Survey Schedule), general fears, parental dental fear, parents' employment and native language was obtained through questionnaires. Data regarding dental health, behavior management problems (BMP) and modes of dental treatment were compiled from dental records. The results showed that child dental fear was associated with missing appointments and dental caries. A proportion of 27% of the children with BMP were dentally fearful, while 61% of the children with dental fear reacted with BMP. A model for stepwise regression analysis showed that general fears, maternal dental fear, and age were important etiological factors in the development of dental fear in children.

Co-localization of L-type Ca2+ channels and insulin-containing secretory granules and its significance for the initiation of exocytosis in mouse pancreatic B-cells.

Abstract: We have monitored L-type Ca2+ channel activity, local cytoplasmic Ca2+ transients, the distribution of insulin-containing secretory granules and exocytosis in individual mouse pancreatic B-cells. Subsequent to the opening of the Ca2+ channels, exocytosis is initiated with a latency < 100 ms. The entry of Ca2+ that precedes exocytosis is unevenly distributed over the cell and is concentrated to the region with the highest density of secretory granules. In this region, the cytoplasmic Ca2+ concentration is 5- to 10-fold higher than in the remainder of the cell reaching concentrations of several micromolar. Single-channel recordings confirm that the L-type Ca2+ channels are clustered in the part of the cell containing the secretory granules. This arrangement, which is obviously reminiscent of the 'active zones' in nerve terminals, can be envisaged as being favourable to the B-cell as it ensures that the Ca2+ transient is maximal and restricted to the part of the cell where it is required to rapidly initiate exocytosis whilst at the same time minimizing the expenditure of metabolic energy to subsequently restore the resting Ca2+ concentration.

Increasing reading and communication skills in children with autism through an interactive multimedia computer program

Abstract: This paper reports on the effect of using an interactive and child-initiated microcomputer program (Alpha) when teaching three groups of children (N = 30) reading and communications skills: (a) 11 children with autism (M chronological age, CA = 9:4 years), (b) 9 children with mixed handicaps (M CA = 13:1), and (c) 10 normal preschool children (M CA = 6:4 years). Their mental age varied from 5:8 years to 6:9 years and all children received computer instruction supplementary to their regular reading and writing activities. Tests of reading and phonological development were carried out at the onset of the training (Start), at the end (Post 1), and at a follow-up evaluation (Post 2). In addition, video observations of the childrens' verbal and nonverbal communication were added at Start and Post 1. The children with autism increased both their word reading and their phonological awareness through the use of the Alpha program. Clearly significant gains were observed during the intervention, but none during the follow-up period. A similar but weaker pattern is observed for the children with mixed handicaps. In contrast, the normal preschool children increased their scores regardless of the program. Analyses of the children's classroom behavior indicate that the intervention succeeded in stimulating verbal expressions among the children with autism and mixed handicap. A significant increase in enjoyment was also noted for the children with autism. It is concluded that the intervention with a motivating multimedia program might stimulate reading and communication in children with various developmental disabilities, but that such interventions must be individually based and include both detailed planning and monitoring from teachers, and parents, as well as from clinicians in charge.

A placebo-controlled trial of a pertussis-toxoid vaccine

Abstract: Background Although many whole-cell vaccines have been effective in preventing pertussis, these vaccines are difficult to standardize and can produce side effects. In Sweden, pertussis became endemic during the 1970s despite vaccination. Because of its limited efficacy, the Swedish-made whole-cell vaccine was withdrawn in 1979. Methods To evaluate the efficacy of an acellular vaccine consisting of pertussis toxin inactivated by hydrogen peroxide (pertussis toxoid), we conducted a randomized, double-blind, placebo-controlled trial in Sweden. Infants were vaccinated with either diphtheria and tetanus toxoids alone (DT toxoids, 1726 infants) or diphtheria, tetanus, and pertussis toxoids (DTP toxoids, 1724 infants) at 3, 5, and 12 months of age. Results There were no serious reactions. With the pertussis vaccine there were slightly more local reactions than with the DT toxoids alone, but the rates of postvaccination fever were the same. The main period of surveillance, which began 30 days after the third vacc...

Birth asphyxia: incidence, clinical course and outcome in a Swedish population

Abstract: A total of 42,203 live infants were born in Goteborg in 1985-1991, and 292 term infants had Apgar scores < 7 at 5 min. Infants with congenital malformations, infections and opioid-induced respiratory depression were excluded and thus 227 infants were included in the birth asphyxia group, which formed the basis of this retrospective study. Clinical signs of mild, moderate or severe hypoxic-ischemic encephalopathy (HIE) were present in 65 infants, and in another 10 infants, sedated and on controlled ventilation, HIE was assumed but grading was not possible. The incidences of Apgar scores < 7 at 5 min, birth asphyxia and birth asphyxia with HIE were 6.9, 5.4 and 1.8 per 1,000 live born infants: 95% of infants resuscitated with bag and mask ventilation only, did well, compared with 1 of 11 in whom resuscitation included adrenaline. Seizures occurred in 27 of 227 infants, beginning in 18 infants within 12 h of birth. Small-for-gestational-age (SGA) infants were overrepresented in the birth asphyxia group but not in the birth asphyxia-HIE group. All infants with severe HIE died or developed neurological damage. Half of the infants with moderate, and all of the infants with mild, HIE were reported to be normal at 18 months of age. A total of 0.3 per 1,000 live born infants died and 0.2 per 1,000 developed a neurological disability related to birth asphyxia. The disabilities were dyskinetic (4), tetraplegic (2), spastic diplegic (2), cerebral palsy and mild neuromotor dysfunction (1). The relatively low incidences of birth asphyxia and HIE were probably due to effective antenatal care.

Nest site selection : a trade-off between concealment and view of the surroundings ?

Abstract: For most birds, nest predation is the main cause of reproductive failure. Many species reduce predation by hiding their nests in vegetation. However, it is unclear whether they maximize cover around nests. Individuals may benefit also by keeping potential predators, food, and conspecifics in view, and selection of nest site may be a trade-off between concealment and visibility. We examined this idea in the Song Thrush Turdus philomelos, which builds cup-shaped nests in trees. For artificial nests, the risk of predation decreased when nests were more concealed within individual trees. However, Song Thrushes did not maximize concealment of nests within trees but selected intermediate concealment from the range of concealment available. The proportion of destroyed natural nests was not related to degree of nest concealment. Song Thrushes also selected patches of intermediate tree density, but tree density did not influence predation rate of artificial nests. These results are consistent with the trade-off hypothesis, which deserves more attention in future studies of nest site selection.

Sclerosing epithelioid fibrosarcoma. A variant of fibrosarcoma simulating carcinoma.

Abstract: We report 25 cases of a peculiar sclerosing epithelioid variant of fibrosarcoma (SEF) simulating an infiltrating carcinoma. The tumors occurred primarily in the deep musculature and were frequently associated with the adjacent fascia or periosteum. The patients' ages were 14 to 87 years (median, 45). Fourteen were male and 11 female. The tumors were located in the lower extremities and limb girdles (12 cases), trunk (9), upper limb girdles (2), and neck (2). They measured 2 to 14.5 cm in greatest dimension (median size, 7 cm) and were gray to white and firm. Histologically, the lesions were characterized by a proliferation of rather uniform, small, slightly angulated, round to ovoid epithelioid cells with sparse, often clear cytoplasm arranged in distinct nests and cords. In all cases there was prominent hyaline sclerosis, sometimes reminiscent of osteoid or cartilage and foci of conventional fibrosarcoma. Occasional myxoid zones with cyst formation and foci of hyaline cartilage, calcification, and metaplastic bone were also seen. Mitotic figures were generally scarce. Vimentin was detected in 13 of 14 cases, epithelial membrane antigen in seven, S100 protein in four, and neuron-specific enolase in two. Cytokeratins were detected with AE1/AE3 and CAM 5.2 in two cases. Leukocyte common antigen, CD68 antigen, HMB45, desmin, and alpha-smooth muscle actin were negative in all cases. In 13 of 14 cases, 75% or more of the cells stained for proliferating cell nuclear antigen (PCNA). Ki67 immunostaining with MIB 1 showed low proliferative activity in all cases, averaging 5% of tumor cells or less. In all cases, p53 was detected by immunohistochemical methods; bcl-2, an antiapoptosis marker, was detected in more than 90% of the cells in 11 of 12 cases. Ultrastructurally, both the epithelioid and spindled tumor cells had features of fibroblasts. Follow-up in 16 cases ranging from 13 months to 17 years 3 months (median, 11 years 4 months) revealed persistent disease or local recurrences in 53% of patients and metastases in 43%. The metastases were to the lungs (4 cases), skeleton (3), chest wall/pleura (3), pericardium (1), and brain (1). Four patients died of disease, four were alive with disease, two were known to be alive but disease status unknown, and six had no evidence of further disease at last follow-up. The data suggest that SEF is a relatively low-grade fibrosarcoma; yet it is fully malignant despite the presence of histologically benign-appearing foci. The proliferation markers PCNA and Ki67 did not correlate with prognosis.(ABSTRACT TRUNCATED AT 400 WORDS)

Central antinociceptive effects of non-steroidal anti-inflammatory drugs and paracetamol. Experimental studies in the rat.

Abstract: Background These studies were undertaken to investigate the site and nature of the antinociceptive effect of NSAIDs (Non-Steroidal Anti-Inflammatory Drugs) and paracetamol in the central nervous system (CNS). Methods Different nociceptive test models were employed: the tail-flick and hot-plate tests (thermoreceptors), the writhing test (visceral chemoreceptors) the "scratching, biting, licking" (SBL) behaviour and the colorectal distension test (mechanoreceptors). Drugs were given intraperitoneally (i.p.), intracerebroventricularly (i.c.v.), intrathecally (i.t.) or as local injection via cannulae implanted stereotactically. Nerve destruction was made by local injection of the neurotoxin 5,7-dihydroxytryptamine (5,7-DHT). Whole brain and spinal cord contents of serotonin and 5-hydroxyindole acetic acid (5-HIAA) were analysed by high pressure liquid chromatography (HPLC). Results Injections of diclofenac induced antinociception in visceral pain models (writhing test, colorectal distension test), but not in two models of somatosensory pain (tail-flick and hot-plate test). The antinociceptive effect of diclofenac (i.p., i.c.v., or i.t.) was reversed by i.p. naloxone. Naloxone also reversed the effect of diclofenac injected locally into thalamic and hypothalamic areas involved in pain transmission as well as in n. paragigantocellularis or n. raphe magnus. In addition, chemical destruction of the n. raphe region attenuated the antinociceptive effect of diclofenac. Inhibition of serotonergic transmission by pretreatment with methiothepin, ritanserin, parachlorophenylalanine (PCPA) or 5,7-DHT also reduced the antinociceptive effect of diclofenac in a visceral pain model. Pretreatment with diclofenac or ibuprofen blocked pain behaviour (SBL) after activation of excitatory amino acid receptors of the NMDA type, but not pain behaviour after activation of AMPA or substance P (SP) receptors. Paracetamol inhibited hyperalgesia after both NMDA and SP. The antinociceptive effects of diclofenac, ibuprofen and paracetamol were reversed by L-arginine, but not by D-arginine. Conclusions The antinociceptive effect of diclofenac involves a central nervous component which may be elicited from several defined areas in the CNS. Part of the antinociceptive effect seems to be mediated by descending inhibitory opioid, serotonin and/or other neurotransmitter systems interfering with visceral pain impulse traffic at the spinal level. NSAIDs and paracetamol interfere with nociception associated with spinal NMDA receptor activation. This effect involves an inhibitory action on spinal nitric oxide (NO) mechanisms. Possibly, the supraspinal antinociceptive effect of NSAIDs may be explained by an analogous action.

Efficiency Measurement in Swedish Dairy Farms: An Application of Rotating Panel Data, 1976–88

Abstract: This paper introduces a new specification of technical inefficiency in panel data models. First, the overall technical inefficiency is decomposed into a persistent component and a residual component. Second, a multistep procedure is used to estimate the parameters of the production function as well as persistent and residual technical inefficiency. The advantage of this multistep procedure is that the parameter estimates are robust to distributional assumptions on the error components. Distributional assumptions are required in the final stage to estimate the residual component of technical inefficiency. The model is used to examine technical efficiency in Swedish dairy farms during the period 1976 to 1988.

Receptive field characteristics of tactile units with myelinated afferents in hairy skin of human subjects.

Abstract: 1. Impulses in single nerve fibres from the lateral antebrachial cutaneous nerve were recorded using the microneurography technique in human subjects. 2. In a sample of fifty-five mechanoreceptive units with fast-conducting nerve fibres, five types were identified, i.e. SAI (slowly adapting type I, Merkel), SAII (slowly adapting type II, Ruffini), hair units, field units and Pacinian-type units. The latter three unit types were all rapidly adapting. 3. The detailed structure of thirty-five receptive fields of SAI, SAII, hair and field units was explored with a method which was objective and independent of the experimenter's skill and experience. A lightweight probe was used to scan the receptive field area in a series of tracks 0.23 mm apart while single-unit activity was recorded. 4. SAI fields were small and composed of two to four well-separated high-sensitivity spots and often, in addition, one minor spot of lower sensitivity. SAII units typically fired spontaneously at a low and regular rate. Most fields consisted of one single spot of high sensitivity with diffuse borders. The hair units innervated ten to thirty-three (or more) hairs, which were evenly distributed over a large area. The field units were characterized by a number of small and closely packed high-sensitivity spots with diffuse borders. A conservative estimate indicated eleven spots per unit. 5. The findings indicate that the sheet of mechanoreceptors on the skin of the forearm is distinctly different from that on the dorsum of the hand and in the face. It seems reasonable to assume that the former is more representative for the hairy skin covering the main parts of the body.

Prediction of progression of the curve in girls who have adolescent idiopathic scoliosis of moderate severity. Logistic regression analysis based on data from The Brace Study of the Scoliosis Research Society.

Abstract: In a study conducted by the Scoliosis Research Society, 159 girls with a mean age of thirteen years (range, ten to fifteen years) who had adolescent idiopathic scoliosis were followed prospectively until skeletal maturity or until the curve had increased 6 degrees or more. All patients had had an initial curve of 25 to 35 degrees and an apical level between the eighth thoracic and first lumbar vertebrae, inclusive. Of the 159 patients, 120 were observed without treatment and thirty-nine were managed with lateral electrical surface stimulation. The curve progressed at least 6 degrees in eighty patients. There was no apparent difference in the outcome between the patients who were managed with observation only and those who were given electrical stimulation. Logistic regression analysis was performed to determine which of eleven factors were predictive of progression of the scoliotic curve. A Risser sign of 0 or 1, an apical level cephalad to the twelfth thoracic vertebra, and an imbalance of ten millimeters or less were found to be independently prognostic of progression of more than 6 degrees. A prognostic model that included these three factors and chronological age allowed correct classification of the curve as either progressive or non-progressive in 81 per cent of these patients who had a thoracic or thoracolumbar adolescent idiopathic scoliosis. The positive predictive value was 82 per cent, the negative predictive value was 80 per cent, and the sensitivity and specificity were each 81 per cent.

Long-term survival of fragment bonding in the treatment of fractured crowns: a multicenter clinical study.

Abstract: In three Scandinavian dental facilities, a series of 334 permanent incisors with fractures of the crown or crown and root was treated by reattachment of the fragment with a resin composite. Two centers (Oslo and Stockholm) employed acid etching of enamel alone for fragment bonding (n = 146), while the third center (Copenhagen) used a combination of enamel etching and dentinal bonding (n = 188). Although the final retention rate of fragment bonding was similar in the two groups, it took the dentinal bonding group almost three times as long to drop to 50% fragment retention. This difference could be attributed to greater bonding strength in the dentinal bonding group, greater risk of second injury in the younger acid-etching group, or difficulty in maintaining a dry operative field in the younger age group. The good fragment retention, acceptable esthetics, and pulpal vitality observed in the present series indicate that reattachment of the coronal fragment is a realistic alternative to placement of conventional resin-composite restorations.

Masticatory muscle influence on craniofacial growth.

Abstract: The influence of the masticatory muscle function on craniofacial growth has been recorded in a series of animal experimental and clinical studies. The common characteristic of these investigations is that the elevator muscles of the mandible influence the transversal and the vertical dimensions of the face. The increased loading of the jaws due to masticatory muscle hyperfunction may lead to increased sutural growth and bone apposition, resulting in turn in an increased transversal growth of the maxilla and broader bone bases for the dental arches. Furthermore, an increase in the function of the masticatory muscles is associated with anterior growth rotation pattern of the mandible and with well-developed angular, coronoid, and condylar processes.

The microbial flora in venous leg ulcers without clinical signs of infection. Repeated culture using a validated standardised microbiological technique.

Abstract: The change of ulcer size in relation to the presence of species and quantities of microorganisms was analysed in 58 patients with venous leg ulcers, all without clinical signs of infection. Microbiological samples were taken on the day of inclusion and then repeated 4 times at monthly intervals or until the ulcer had healed or was too small to be cultured from. There was growth of microorganisms in all ulcers, and the numbers were below 10(4) per mm2 of ulcer surface in all cases. No correlation was found between ulcer size change and the species and amounts of microorganisms. Sixty-nine species were isolated. Staphylococcus aureus was found in 88%, Enterococcus faecalis in 74%, Enterobacter cloacae and Peptococcus magnus in 29%, and fungi in 11% of the samples. One or more obligate anaerobe species was found in 41% of the samples and in half of the ulcers and constituted 62% of all bacterial species. The colonising ulcer flora was markedly constant over time in the individual ulcers regardless of change in size. Resident bacterial species were found in 57 of the 58 ulcers. If all samples were considered, the microorganisms were associated with not more than one fifth of the variability in healing rate, as shown by linear multiple regression analysis. The same species of microorganisms were found in ulcers that decreased (or healed) and in those that increased in size. Although an association between the microorganisms and ulcer healing could not be ruled out in this study, there seems to be no indication for routinely performed culture in the absence of clinical signs of infection in venous leg ulcers.

Unified description of accretion flows around black holes

Abstract: We provide a unified description of thermal equilibria of black hole accretion disks, including the newly discovered advection-dominated solutions. We classify the solutions on the basis of optical depth and impotance of advection cooling. We demonstrate that only four physically distinct topological types of equilibria exist. Two of the types correspond to optically thin and optically thick equilibria, while the other two types are distinguished by whether advection is negligible or dominant. A stable Shakura-Sunyaev disk exists only for accretion rates dot-M below a certain maximum. However, there is a critical viscosity parameter alpha(sub crit), which is a function of radius, such that for alpha greater than alpha(sub crit) advection-dominated solutions exist for all dot-M. Even when alpha less than alpha(sub crit), the advection-dominated solutions are available for a wide range of dot-M except for a gap around the Eddington rate. We therefore suggest that advection-dominated flows may be more common than standard thin disks in black hole systems. For certain ranges of radii and dot-M, no stable steady state solution is possible. In these cases, we suggest that limit cycle behavior may occur, leading to variability.

Treatment of fenestration and dehiscence bone defects around oral implants using the guided tissue regeneration technique: a prospective multicenter study.

Abstract: Four clinical centers, using the Branemark System and with personnel trained in the use of Gore-Tex Augmentation Material (GTAM), participated in a prospective study of 45 patients 18 to 83 years of age. A total of 55 implants were placed with membranes because of local bony defects (fenestration or dehiscence). Dehiscence and fenestration defects were evaluated as one group. The mean initial defect height was 4.7 mm (SD = 3.0). After healing, the remaining defect height was reduced to 1.1 mm (SD = 2.3). The decrease in surface exposure was significant. Complications were primarily attributed to exposure of six membranes during the early healing period. The cumulative survival rate was 84.7% in maxillae and 95.0% in mandibles after 2 years of follow-up. The surgical application of GTAM to produce bone in localized bony defects around oral implants seems to be a predictable method that may reduce the need for extensive augmentation surgery in patients with insufficient jaw bone volume.

Neurobiology and clinical aspects of neuropeptide Y.

Abstract: Although a large and still increasing number of neuroactive peptides have been discovered in the mammalian brain over the years, it has been difficult to link most of these molecules with specific brain functions and/or brain diseases. A lack of pharmacological tools has hampered the study of brain peptide systems and the elucidation of which among these systems have retained important physiological functions through phylogenesis. Neuropeptide Y (NPY) is one the most abundant neuropeptides in the mammalian brain. A combination of basic and clinical studies has made it possible to circumvent some of these difficulties and provides evidence for a role of NPY in the control of endocrine hypothalamic and pituitary functions, in hypothalamic control of food intake and circadian rhythm, and in limbic emotional integration. Of particular interest is NPY's unique action as an endogenous anxiolytic and its possible role in clinical states of anxiety and depression. Here, we review the biology, anatomy, and physiology of central NPY systems and studies of these systems in various disease states.