Objective response to radiation therapy and long-term survival of patients with WHO grade II astrocytic gliomas with known LOH 1p/19q status

BACKGROUND: WHO grade II gliomas are often approached by radiation therapy (RT). However, little is known about tumor response and its potential impact on long-term survival. PATIENTS AND METHODS: Patients subjected to RT were selected from the own database of WHO grade II gliomas diagnosed between 1991 and 2000. The volumetric tumor response after RT was assessed based on magnetic resonance imaging and graded according to standard criteria as complete, partial (PR, >or= 50%), or minor (MR, 25% to <50%). RESULTS: There were 24 astrocytomas and three oligoastrocytomas. 21 patients (78%) were dead at follow-up (mean survival 74 months). None of the patients had chemotherapy. Objective response occurred in 14 patients (52%, five PR and nine MR) but was not associated with overall survival. The vast majority of the tumors had no loss of heterozygosity (LOH) 1p and/or 19q (86%). CONCLUSION: Approximately 50% of patients with astrocytic WHO grade II gliomas respond to RT despite the absence of LOH for 1p/19q. The potential predictive factors for response and the impact of response on overall survival remain unclear.

Prospects for microbeam radiation therapy of brain tumours in children to reduce neurological sequelae

Microbeam radiation therapy (MRT), a form of experimental radiosurgery of tumours using multiple parallel, planar, micrometres-wide, synchrotron-generated X-ray beams ('microbeams'), can safely deliver radiation doses to contiguous normal animal tissues that are much higher than the maximum doses tolerated by the same normal tissues of animals or patients from any standard millimetres-wide radiosurgical beam. An array of parallel microbeams, even in doses that cause little damage to radiosensitive developing tissues, for example, the chick chorioallantoic membrane, can inhibit growth or ablate some transplanted malignant tumours in rodents. The cerebella of 100 normal 20 to 38g suckling Sprague-Dawley rat pups and of 13 normal 5 to 12kg weanling Yorkshire piglets were irradiated with an array of parallel, synchrotron-wiggler-generated X-ray microbeams in doses overlapping the MRT-relevant range (about 50-600Gy) using the ID17 wiggler beamline tangential to the 6GeV electron synchrotron ring at the European Synchrotron Radiation Facility in Grenoble, France. Subsequent favourable development of most animals over at least 1 year suggests that MRT might be used to treat children's brain tumours with less risk to the development of the central nervous system than is presently the case when using wider beams.

Short-term effects of hygiene education for preschool (kindergarten) children: a clinical study

AIM: To evaluate the outcomes of short (15 minutes) oral hygiene vs. hand hygiene education for preschool children 4 weeks after these interventions. MATERIALS AND METHODS: Sixty-one preschool children (age range 4-6 years) attending four kindergarten classes participated in a 15-minute health education programme on the importance of body cleanliness for general health. In addition, specific instructions on oral hygiene were provided for two randomly selected classes (30 children), while the remaining two classes (31 children) were given instruction of hand and nail cleaning. The oral hygiene status was assessed usingthe plaque control record (PCR). The cleanliness of the hands and fingernails was determined using a hand hygiene index (HHI) and a nail hygiene index (NHI). All three parameters were assessed before the intervention as well as 4 weeks thereafter. RESULTS: Four weeks after education, the PCR had improved for all children from 79.95% to 72.35% (p < 0.001). The NHI had improved from 74.91% to 61.71% (p < 0.001). In addition, the mean PCR of the children given oral hygiene instruction decreased from 83.67% to 72.40%, while the mean PCR of the children given hand and nail cleaning instruction decreased from 76.23% to 72.29% (interaction effect 'time x type of instruction': p = 0.044). Girls' PCR improved significantly more than boys' PCR (Girls, 80.98 vs. 69.71; boys, 78.33 vs. 75.31; p = 0.021). CONCLUSIONS: The results of the study show that even a short, school-based educational intervention at an early age may affect children's oral health promotion significantly. Teachers should, therefore, be encouraged to educate children from an early age about oral hygiene promotion.

CO2 laser-irradiation through topically applied fluoride increases acid resistance of demineralised human enamel in vitro

PURPOSE: To evaluate the effect of CO2 laser treatment through topically applied amine fluoride solution on demineralised enamel. MATERIALS AND METHODS: Sixty extracted human molar crowns were selected and cut longitudinally into half. One half was subjected to a 10-day pH-cycling procedure to create caries-like lesions, whereas the other was left non-demineralised. The following treatments were randomly assigned (one treatment per tooth, on respective non-demineralised and demineralised matched specimens): exposure to a 1% amine fluoride solution for 15 s without irradiation (group I), irradiation for 15 s with a continuous-wave CO2 laser (group II), or laser-treatment for 15 s through the amine fluoride solution applied immediately beforehand (group III). Fluoride uptake (n = 30) and acid resistance (n = 30) were determined after treatment. Enamel surface alterations after laser irradiation were monitored using scanning electron microscopy. RESULTS: In groups I and III, an increased fluoride uptake was detected (p < or = 0.05). Laser irradiation through topical fluoride resulted in an increased acid resistance of sound and demineralised enamel specimens in deeper layers (p < or = 0.05). In addition, less surface alterations were observed in SEM examination of specimens irradiated through the amine fluoride solution compared with counterparts treated with laser only. CONCLUSIONS: CO2 laser light application through an amine fluoride solution may be instrumental in enhancing acid resistance of sound and demineralised enamel.

Clinical effects of interdental cleansing on supragingival biofilm formation and development of experimental gingivitis

PURPOSE: The aim of the present study was to test the effects of interdental cleansing with dental floss on supragingival biofilm removal in natural dentition during a 3-week period of experimental biofilm accumulation. MATERIALS AND METHODS: The present study was performed as a single-blind, parallel, randomised, controlled clinical trial using the experimental gingivitis model (Löe et al, 1965). Thirty-two students were recruited and assigned to one of the following experimental or control groups: Group A used a fluoride-containing dentifrice (NaF dentifrice) on a toothbrush for 60 s twice a day, Group B used an unwaxed dental floss twice a day, Group C used a waxed dental floss twice a day in every interproximal space and Group D rinsed twice a day for 60 s with drinking water (control). RESULTS: During 21 days of abolished oral hygiene, the groups developed various amounts of plaque and gingivitis. Neither of the cleansing protocols alone allowed the prevention of gingivitis development. Toothbrushing alone yielded better outcomes than did any of the flossing protocols. Interdental cleansing with a waxed floss had better biofilm removal effects than with unwaxed floss. CONCLUSIONS: Toothbrushing without interdental cleansing using dental floss and interdental cleansing alone cannot prevent the development of gingivitis.

Restoration margins in young adolescents: a clinical and radiographic study of Swiss Army recruits

PURPOSE: The aim of the present study was to report the radiographical prevalence of overhanging fillings in a group of Swiss Army recruits in 2006 and to relate the dimensions of the overhangs to clinical parameters. MATERIALS AND METHODS: A total of 626 Swiss Army recruits were examined for their periodontal conditions, prevalence of caries, and stomatological and functional aspects of the masticatory system and halitosis. In particular, the present report deals with the presence or the absence of fillings, the presence or the absence of overhangs and their relation to clinical and radiographic parameters. RESULTS: A total of 16,198 interdental sites were evaluated on bitewing radiographs. Of these sites, 15,516 (95.8%) were sound and 682 (4.2%) were filled. Amalgam restorations were found in 94.1% and resin composite fillings in 5.9% of the sites. Of these 682 sites, 96 (14.1%) yielded overhanging margins of various sizes. This low prevalence of fillings represents not only a substantial reduction when compared with a similar Swiss Army study (Lang et al, 1988), but also an improvement in the quality of dental care delivery to young Swiss males. Plaque Index and Gingival Index increased statistically significantly with the presence of fillings, when compared with healthy non-filled sites. Clinical parameters that were significantly associated with the presence of overhangs included clinical attachment loss. Moreover, between 1985 and 2006 the prevalence of fillings was significantly reduced from 20.0% to 4.2% of all surfaces. Furthermore, the marginal fit of the fillings improved from 33.0% with overhangs to 14.1%. CONCLUSIONS: A significant improvement was observed in the periodontal and dental conditions of young Swiss males that was shown to have taken place within the previous two decades. From 1985 to 2006, the prevalence of fillings was reduced fourfold and that of overhanging margins twofold, documenting an improvement in the quality of restorative dentistry.

Elevated serum triiodothyronine and intellectual and motor disability with paroxysmal dyskinesia caused by a monocarboxylate transporter 8 gene mutation

Monocarboxylate transporter 8 (MCT8 or SLC16A2) is important for the neuronal uptake of triiodothyronine (T3) in its function as a specific and active transporter of thyroid hormones across the cell membrane, thus being essential for human brain development. We report on a German male with Allan-Herndon-Dudley syndrome presenting with severe intellectual and motor disability, paroxysmal dyskinesia combined with truncal muscular hypotonia, and peripheral muscular hypertonia at his current age of 9 years. Additionally, the patient has a lesion in the left putamen region revealed by magnetic resonance imaging and elevated serum T3 levels. The male appeared to have a hemizygous mutation (R271H) in the MCT8 gene that was sequenced directly from genomic DNA and occurred de novo in the maternal germline, as both his mother and his sister were not carriers of the mutation. Ruling out a common polymorphism, 50 normal individuals of the same ethnic background did not harbour the mutation. The identified MCT8 gene mutation (R271H) is very likely to be the genetic cause for neuronal hypothyroidism despite elevated serum T3 levels.

The chemokines CCL11, CCL20, CCL21, and CCL24 are preferentially expressed in polarized human secondary lymphoid follicles

Chemokines regulate cellular trafficking to and from lymphoid follicles. Here, the distribution pattern of four CCL chemokines is defined by in situ hybridization in human lymphoid follicles from tonsils and lymph nodes (LNs) of newborns and adults. Cells expressing CCL11 (eotaxin) and CCL20 (Exodus) were preferentially located within follicles, while cells expressing CCL21 (secondary lymphoid-tissue chemokine) and CCL24 (eotaxin-2) mRNA were almost exclusively found in the perifollicular areas. Hence, the two CCR3-binding chemokines, CCL11 and CCL24, showed a mutually exclusive expression pattern in the intra- and extra-follicular areas, respectively. Chemokine gene expression paralleled follicular maturation: in tonsils, where approximately 80% of follicles are polarized, CCL11 and CCL20 mRNA-positive cells were detected more frequently than in lymph nodes from adults, where about half of follicles are non-polarized. No intrafollicular chemokine expression was detectable in the primary follicles from newborns. Extrafollicular cells expressing CCL21 and CCL24 were again more frequent in tonsils than in LNs from adults. The observed preferential presence of cells expressing CC chemokines in polarized human lymphoid follicles indicates that chemokines are not only instrumental in the induction of follicle formation, but may also be involved in their further differentiation.