Newman-Keuls Research Articles

Influence of Toothpaste pH on Its Capacity to Prevent Enamel Demineralization.

Aim:This study evaluated in vitro the remineralization capacity of commercial toothpastes with different fluoride (F) concentrations and their effectiveness when they are acidified.Materials and Methods:One hundred and twelve caries-free teeth were used to prepare enamel specimens, and the specimens were divided into 16 groups (n = 7). Baseline surface Vickers microhardness was measured for all the specimens and all the tested groups were subjected to the pH-cycling regime involved five demineralization challenges each day for 10 days, and surface Vickers microhardness was then measured. Once daily, specimens were exposed for 30 min after last demineralization challenge of the day to the slurry of each toothpaste containing 1450 ppm F, 1000 ppm F, 450 ppm F, and 0 ppm F. The slurry was in original pH or acidulated on 6.5, 6.0, or 5.5 pH. The difference among tested group was assessed by analysis of variance and Newman–Keuls test (P < 0.05).Results:The highest increase in microhardness was detected after treatment with toothpaste containing 1450 ppm fluoride (percentage of increase in microhardness was 6.20%), and the biggest loss was detected after treatment with toothpaste containing no fluoride (percentage of decrease was 6.82%), but there was no significant difference between tested groups.Conclusions:The highest increase in microhardness was detected after treatment with toothpaste containing more fluorides (1450 ppm F) regardless of the acidity.

Effect of Er:YAG laser energy densities on thermally affected dentin layer: Morphological study.

Physical and chemical composition of dentin is subject to modification when irradiated with Er:YAG laser. Temperature rise causes water evaporation and micro-mechanical ablation of dentin. The misuse of laser parameters could affect negatively dentin collagen fibers leading to failure in bonded composite restorations. The aim of this in vitro study was to evaluate the effect of Er:YAG laser radiation at different levels of energy on the morphology of thermally affected dentin layer. Forty-eight freshly extracted human third molars were randomly divided into six groups (n = 8). In all groups, except for the control groups, dentin was subject to irradiation with H02 handpiece Er:YAG laser in non-contact mode (SSP mode = 50 µs; 10 Hz; speed of 1 mm/second; air 6 mL/min; and water 4 mL/min) with the following levels of energy (40, 60, 80, 100, and 120 mJ) respectively. Teeth were sliced longitudinally. Photo-ablated cavities were observed. The cavity depth and dentin fiber collagen deterioration were measured. Laser irradiation increased the depth of dentinal crater from 46.57 µm to 178.2 µm, when energy level increased from 40 mJ to 120 mJ. A superficial black layer, representing dentinal affected collagen fibers, was present in all groups except for control group. When comparing the thickness of the black layer, there was no significant difference between groups. It increased at 40 mJ to 28.17 µm then decreased to 15.19 µm at 60 mJ and then increased again for 80 mJ to 19.93 µm, 100 mJ to 22.87 µm and 120 mJ to 28.53 µm. Only one group (60 mJ) showed low values and significant difference as compared to the other irradiated groups, when multiple comparisons tests (ANOVA) were made using Newman-Keuls test. Dentin organic matrix presented the minimum alteration when Er:YAG laser is used specifically at an appropriate level of energy (60 mJ).

Effect of At-home and In-office Bleaching on Marginal Microleakage in Composite Resin Restorations using Two Adhesive Systems

The aim of this study is to assess marginal microleakage of cervical cavities restored with composite resins and two different adhesive techniques subjected to at-home and in-office bleaching. In this randomized, blind laboratory experiment, 60 bovine teeth recently extracted were collected and divided into six groups (n = 10 each group). The teeth received cervical cavity preparations (2 mm × 3 mm × 1 mm) with enamel margins. Two different adhesive systems were used (Single Bond 2 and Clearfil SE Bond), in addition to composite resin (Z250). Restored teeth received two different bleaching gels (Opalescence PF and Opalescence Boost). Teeth were thermo-cycled and analyzed under confocal laser scanning microscopy. No significant differences were observed (p > 0.05) in microleakage scores between the two groups not subjected to bleaching nor between the four groups that received bleaching treatment (p > 0.05), regardless of the gel and adhesive system employed. However, when comparing nonbleached with bleached teeth, those not subjected to bleaching showed statistically lower marginal microleakage scores (p < 0.05). Data were statistically analyzed using the Kruskal-Wallis test followed by Student-Newman-Keuls post hoc test, with significance set at 5%. Marginal microleakage in composite resin restorations is influenced by the action of bleaching agents used both at-home and in-office, regardless of the adhesive system employed (total-etch or self-etch). Both at-home and in-office bleaching agents have an influence on the adhesive interface of resin restorations, producing changes and inducing marginal leakage.

Annual blood pressure dynamics and weather sensitivity in women

To study the annual cycle of blood pressure (BP) and weather sensitivity in normotensive women aged 20-59 years. The same group of 25 non-smoking women who had been living in the European North of Russia (62° N, 51° E) almost since their birth and were engaged in moderate-intensity mental labor was daily examined. During a year, there were 11823 blood pressure measurements using the Korotkoff technique; heart rate was calculated by palpation. These meteorological parameters were taken at the websites: http://meteo.infospace.ru and ftp://ftp.ngdc.noaa.gov/stp/geomagnetic_data/indices/kp_ap. The statistical significance of differences in the indicators was determined using the Fisher's test and the Newman-Keuls test. The study used a correlation analysis with the calculation of the Spearman's rank correlation coefficient. The maximum systolic and diastolic BP values were revealed in February and January, respectively. The minimum values of systolic BP were detected in July; those of diastolic BP were in August. An individual-based analysis of sensitivity to environmental variations showed that about 88% of the women responded to atmospheric temperature; nearly 44% did to geomagnetic activity; almost 24% were sensitive to relative air humidity, and about 16% of the women were to atmospheric pressure. The dynamics of systolic and diastolic BP in the annual cycle of women depends on meteorological factors and suggests that there is a change in the priorities of its control in different periods of a year.

Effect of local anesthesia on weight gain of pre-weaning piglets submitted to castration

The policies of welfare on animal production have been expanded to improve the animal needsand match the demands of the consumer market. Castration represents a questionable welfarefactor related to pig production. The aim of this study was to investigate the influence of theuse of local anesthesia before castration on productive performance in pre-weaning piglets,assessed by weight gain. Animals were divided into two treatments: 1) castration without localanesthesia (SURG; n = 52) and 2) castration after intra-testicular local anesthesia (SURG+LA;n = 52) when animals were three to seven days old. Piglets were weighed before (W0) and atseven (W1) and 14 days (W2) after orchiectomy, when they were weaned. Statistical analysiswas performed by one-way analysis of variance (ANOVA) followed by Student-NewmanKeuls multiple comparison test to investigate differences between groups. There were nodifferences in Weight (W2) and weight gain at weaning between SURG+LA animals comparedto SURG animals (3.57 ± 0.60 kg and 3.74 ± 0.71 kg, respectively; p = 0.17). According to theexperimental conditions of this study, local anesthesia before castration of piglets does notaffect weight gain at weaning, warranting further investigation following the effect of localanesthesia prior to castration until the slaughtering phase.

Characterization of Low-Molecular-Weight Heparins by Strong Anion-Exchange Chromatography.

Currently, detailed structural characterization of low-molecular-weight heparin (LMWH) products is an analytical subject of great interest. In this work, we carried out a comprehensive structural analysis of LMWHs and applied a modified pharmacopeial method, as well as methods developed by other researchers, to the analysis of novel biosimilar LMWH products; and, for the first time, compared the qualitative and quantitative composition of commercially available drugs (enoxaparin, nadroparin, and dalteparin). For this purpose, we used strong anion-exchange (SAX) chromatography with spectrophotometric detection because this method is more helpful, easier, and faster than other separation techniques for the detailed disaccharide analysis of new LMWH drugs. In addition, we subjected the obtained results to statistical analysis (factor analysis, t-test, and Newman-Keuls post hoc test).

Cuspal flexure of composite-restored typodont teeth and correlation with polymerization shrinkage values

ObjectiveThe relationship between post-gel shrinkage, total shrinkage, and cuspal flexure was examined. Cuspal flexure was measured on restored typodont teeth, which offered a standardized tooth shape for comparison of shrinkage stress effects among restorative composites. MethodsSix restorative composites were compared (Filtek LS, Venus Flowable, Tetric EvoCeram, Filtek Flowable, Esthet-X, and Filtek Supreme). Total shrinkage was determined from changes in projected surface area before and after polymerization (n=10). Post-gel shrinkage was determined with a biaxial strain gauge that measured strain development during polymerization (n=10). Cuspal flexure was determined using typodont maxillary second premolars with standard MOD slot preparation (n=10). Flexure was determined by comparing the three-dimensionally scanned cuspal surfaces before and after restoration. Restoration bonding to the typodont cavity was achieved by sandblasting and adhesive application. Bond integrity was verified by measuring dye penetration. Results were analyzed using ANOVA and Student–Newman–Keuls post hoc test (significance level 0.05). Pearson was used for correlations. ResultsTotal and post-gel shrinkage were significant different for all composites (t-test; P<0.001). Depending on the composite, only 9–41% of the total shrinkage was recorded as post-gel shrinkage. Bond integrity of restored typodont teeth was 96–99%. Cuspal flexure correlated strongly with post-gel shrinkage, but there was no correlation with total shrinkage. SignificanceCuspal flexure of restored typodont teeth showed the effect of shrinkage stress caused by polymerizing composite restorations, ensuring standardization while maintaining the effects of tooth/cavity geometry. Post-gel shrinkage gave a good indication to screen composites for the stress they may generate; total shrinkage had no direct correlation with stress.

Fluoride toothpastes containing micrometric or nano-sized sodium trimetaphosphate reduce enamel erosion in vitro

Objective: To evaluate the effect of fluoride toothpastes supplemented with micrometric or nano-sized sodium trimetaphosphate (TMP or TMPnano, respectively) on enamel erosion in vitro, as well as the influence of salivary acquired pellicle and saliva.Material and methods: Bovine enamel blocks (n = 120) were randomly assigned into the following experimental toothpastes: no F/TMP/TMPnano (Placebo); 1100 ppm F (1100 ppm F); 1100 ppm F plus 3% TMP or 3% TMPnano (1100 TMP or 1100 TMPnano, respectively) and 5000 ppm F (5000 ppm F). Erosive challenge was performed by immersion of the blocks in citric acid for 5 min, followed by 2 h immersion in human or artificial saliva, 4×/day, during 5 days. After each erosive challenge, blocks were exposed to slurries of the toothpastes. Enamel erosion (µm), surface hardness (SHf) and cross-sectional hardness (ΔKHN) were analyzed as response variables and the data were submitted to two-way ANOVA, followed by the Student–Newman–Keuls test (p < .05).Results: 1100 TMPnano significantly reduced enamel loss when compared to 1100 TMP (p = .002), reaching values similar to those promoted by 5000 ppm F (p = .96). 1100 ppm F presented significantly lower enamel loss than Placebo (p < .001), and higher than 1100 TMP (p < .001). Significantly higher SHf and lower ΔKHN was observed for 1100 TMPnano and 5000 ppm F when compared with the other groups (p < .001). The type of saliva did not influence enamel erosion, SHf and ΔKHN for the groups treated with TMP-containing toothpastes.Conclusion: The addition of 3% TMPnano to 1100 ppm F toothpastes significantly increases the protective effect against enamel erosion in vitro when compared with its counterparts with micrometric TMP or without TMP. This effect was not influenced by the presence of acquired enamel pellicle and saliva.

Functional interaction between N-methyl-D-aspartate receptor and ascorbic acid during neuropathic pain induced by chronic constriction injury of the sciatic nerve.

Neuropathic pain is a chronic pain condition, which is resistant to therapy. Ascorbate was released because of the activation of glutaminergic neurons. Due to the important role of N-methyl-D-aspartate (NMDA) receptors in the pathophysiology of neuropathic pain, this study investigated the analgesic efficacy of ascorbic acid (AA) in neuropathic pain condition and the role of NMDA receptors in this effect. For this purpose, adult male rats were randomly allocated to experimental groups (n=8 in each group). Neuropathic pain was induced by chronic constriction injury (CCI) of the sciatic nerve. During the second week after CCI, animals received a single injection of 1, 3, 5, or 10 mg/kg of AA intraperitoneally and pain threshold was determined 15 and 60 min later. The antinociceptive effect of chronic administration was also evaluated by intraperitoneal injection (IP) of 3 mg/kg AA for 3 weeks. To determine the role of NMDA receptors, separate groups of animals 30 min after single injection of AA (1 mg/kg) animals received i.p. injection of ketamine (5 mg/kg), MK-801 (0.01 mg/kg), or glutamate (1000 nmol) and were tested 20 min afterwards. Data analyzed by ANOVA and Newman-Keuls tests and p<0.05 were considered as significant. IP of 3, 5 and 10 mg/kg increased the pain threshold during the second week after CCI (p<0.05, F=3 in tactile allodynia and p<0.01, F=3.2 in thermal and mechanical hyperalgeisa). Chronic administration of AA also produced antinociceptive effect. Ascorbic acid (1 mg/kg, i.p.) inhibited MK-801 and ketamine-induced antinociception response significantly (p<0.001, F=2). It also prevented the analgesic effect of glutamate administration (p<0.001, F=2). The results indicated that AA produced a dose-dependent antinociceptive effect that seems to mediate through its interaction with NMDA receptors.

PP.29.21] IMPAIRED HEART RATE VARIATION WHEN STANDING

Objective: a- To evaluate associations between heart rate variation when standing (HRVS) and vascular stiffness in hypertensives and normotensives. b-To determine independent predictors of impaired HRVS (I-HRVS) in these populations. Design and method: 396 consecutive subjects who attended to the Champagnat Cardiometabolic Center of Austral Hospital were evaluated. The exclusion criteria were: age below 18/above 80 years, secondary hypertension, heart disease, anaemia, diabetes, sympatholitics, and chronotropic drugs. HR, BP (OMROM HEM-781CPINT) and PWV (Mobil-O-Graph, IEE) were measured in supine position after 5 minute rest, and HR was determined again then of 3 minutes of standing position. HRVS was calculated between standing and supine positions. PWV was evaluated according to sextiles of HRVS in hypertensive and normotensive patients (ANOVA, Student Newman Keuls). I-HRVS was defined as those HRVS values contained in the first sextile (lower HRVS). Independent predictors of l-HRVS, adjusted for age, sex, BP, anthropometric factors and medications, were determined. (MEDCALC v12.5.0.0). Results: 314 patients were included: 162 treated hypertensives (54.7 ± 10.6 years, 134 ± 19/86 ± 13 mm Hg, 58.0% males) and 152 normotensives (47.7 ± 10.2 years, 119 ± 10/77 ± 8 mm Hg, 41.4% males). PWV presented a negative relationship across sextiles of HRVS in hypertensives (p = 0.03) and normotensives (p = 0.01). l-HRVS resulted below 2 beats in hypertensives and below 5 beats in normotensives. In univariate analysis, supine HR, sex, PWV and calcium channel blockers were different according to sextiles of HRVS in hypertensives. Supine HR and PWV were also different among sextiles of HRVS in normotensives. In logistic regressions, only supine HR and PWV were independent predictors of I-HRVS in hypertensives (HR: p = 0.0009, and PWV: p = 0.03) and normotensives (HR: p = 0.0002, and PWV: p = 0.03).Conclusions: Across the broad spectrum of BP, I-HRVS was related independently with increased arterial stiffness and higher basal HR. This findings may be explained through a lower baroreceptor functioning secondary to vascular stiffness, as a cause of the lesser parasympathetic cardiac control observed in this subjects. Thus, I-HRVS would be a simple marker of early vascular aging and autonomic dysfunction both in normotensive and hypertensive patients.

Estrogen Status Gates Effects of Kappa-Opioid Receptor on Temporomandibular Joint-Responsive Neurons at the Spinomedullary Junction in Female Rats.

To determine whether estrogen status alters κ-opioid inhibition of nociceptive processing by affecting temporomandibular joint (TMJ) input to neurons in the trigeminal subnucleus caudalis [Vc]/C1-2 region at the spinomedullary junction in female rats. TMJ-responsive neurons were recorded in laminae I-II of the Vc/C1-2 region at the spinomedullary junction of ovariectomized female rats treated for 2 days with low-dose estradiol (LE group; 2 mg/day) or high-dose estradiol (HE group; 20 mg/day). Under isoflurane anesthesia, TMJ neurons were activated by adenosine triphosphate (ATP; 1 mM, 20 μl), which was injected into the joint space before and after cumulative doses of a κ-opioid receptor (KOR) agonist (U50488) given systemically (0.03, 0.3, and 3 mg/kg, intravenously) or by local application to the dorsal surface of the Vc/C1-2 region (1 and 10 nmol/30 μl). Analysis of variance and Newman-Keuls test were performed to compare the data. Systemic U50488 caused a dose-related inhibition of ATP-evoked neuronal activity in HE rats and reduced the size of the neuronal cutaneous receptive field (RF), while effects in LE rats were not significant. Systemic U50488 reduced the spontaneous activity of TMJ-responsive neurons to similar levels in LE and HE groups. Locally applied U50488 inhibited ATP-evoked neuronal activity in HE rats, but not in LE rats. Systemic and local administration of the KOR antagonist nor-binaltorphinine (nor-BNI) partially reversed the decrease in Rmag induced by U50488, but had no effect on neurons from LE rats. These results indicate that KOR-dependent effects on TMJ-responsive neurons in the superficial laminae of the Vc/C1-2 region in female rats are differentially modified by high and low estrogen status. The site of action for estrogen-induced modulation of TMJ neuronal activity by KOR likely includes second-order neurons in the Vc/C1-2 region.

Effect of physical activity level on body build and physical fitness of girls and boys aged 10-19 years

Aim: The study was aimed to evaluate the somatic build and physical fitness of children and adolescents aged 10-19 years depending on their physical activity. Basic procedures: The survey was conducted in the years 2008-2009 with 925 girls and 1016 boys aged 10-19 years, attending rural and urban schools in the Bielsk District. The following basic anthropometric measures were taken: body height, body mass, arm and shank circumference, thickness of three skinfolds (over the triceps, over the scapula, and over the iliac crest). The Body Mass Index (BMI) was computed from values of body height and mass measurements. Numeric values of somatotypological components were calculated as well; these including: endomorphy, mesomorphy, and ectomorphy. Physical activity was evaluated based on the trials of the European Physical Fitness Test battery, and stratified acc. to a 3-level scale: low activity – up to 1 hour, moderate activity – between 1 and 3 hours, and high activity – 4 and more hours. In groups of the physical activity of girls and boys, values of somatic traits and results of motor tests were normalized with the use of equations indicating dependencies of mean values and standard deviations on age, according to Stupnicki et al. [1]. Significance of differences between the studied groups was evaluated using the analysis of variance ANOVA with “post-hoc” Newman-Keuls test. Results: The surveyed girls and boys with the highest physical activity were characterized by the lowest values of somatic traits, except for body height, and by the best results of physical fitness. Greater differences between results were observed in the girls. Conclusions: A correlation was demonstrated between the physical activity and somatic build and physical fitness of the surveyed girls and boys. Key words: physical activity, physical development, physical fitness, children and adolescents

Evaluation of three tidal volumes (10, 12 and 15 mL kg−1) in dogs for controlled mechanical ventilation assessed by volumetric capnography: a randomized clinical trial

ObjectiveTo evaluate three routinely used tidal volumes (VT; 10, 12 and 15 mL kg−1) for controlled mechanical ventilation (CMV) in lung-healthy anaesthetized dogs by assessing alveolar ventilation (VTalv) and dead space (DS). Study designProspective, randomized clinical trial. AnimalsA total of 36 client-owned dogs. MethodsDogs were randomly allocated to a VT of 10 (G10), 12 (G12) or 15 (G15) mL kg−1. After induction CMV was started. End-tidal carbon dioxide tension was maintained at 4.7–5.3 kPa by changing the respiratory frequency (fR; 6<fR<30 breaths minute−1). After 29 minutes, cardiovascular and respiratory variables were recorded for 3 minutes using a multiparameter monitor, volumetric capnography (VCap) and a blood gas analyser. The ratios of VTalv to body weight (VTalv kg−1) and airway DS to VT (VDaw/VT), Bohr's DS (VDBohr), Enghoff's DS (VDBE) and the volume of expired carbon dioxide per breath (VTCO2,br) were calculated. Mean airway pressure (MawP), fR and peak inspiratory pressure (PIP) were recorded. Data were analysed using one-way anova and Student–Newman–Keuls tests with a statistical significance set at p<0.05. ResultsNo differences were observed for demographic data and cardiovascular variables between groups. A total of three dogs were excluded because of technical difficulties and one because of fR>30. VTalv kg−1 (p=0.001) increased and VDBohr (p=0.002) decreased with greater VT. VTCO2,br (p=0.017) increased and VDaw/VT (p=0.006), VDBE (p=0.008) and fR (p=0.002) decreased between G10 and G15. PIP (p=0.013) was significantly higher in G15 compared with that in G10 and G12. No changes were observed in MawP. Conclusions and clinical relevanceA VT of 15 mL kg−1 is most appropriate for CMV in lung-healthy dogs (as evaluated by respiratory mechanics and VCap) and does not impair cardiovascular variables.

Evaluation of nutritional plans for meat quail

In this study, we evaluated three nutritional plans for quail from 1 to 42 days of age on performance, carcass quality, and economic viability. A total of 210 European quail were distributed into three treatments in a randomized complete design with five replicates and 14 birds in each plot. The following three treatments were tested: nutritional plan 1 - one diet, provided from 1 to 42 days of age; nutritional plan 2 - two diets, provided from 1 to 21 and 22 to 42 days of age; and nutritional plan 3 - three diets, provided from 1 to 14, 15 to 35, and 36 to 42 days of age. Data were subjected to analysis of variance and means were compared by the Student Newman Keuls (SNK) test at the 5% probability level. At 42 days of age, one bird from each sex, of each experimental unit, was slaughtered to evaluate the yields of carcass, breast, legs, and abdominal fat. Nutritional plans per rearing stage with two or three diets provided similar production performances and better feed conversion than the plan including only one diet. Studied carcass characteristics did not differ between treatments. The nutritional plan with three diets provided the best economic viability. The best nutritional plan for meat quail was that containing three types of diet, because it provided a lower cost with feed per kilogram of quail produced without compromising performance or carcass characteristics.

Fluoride varnishes containing sodium trimetaphosphate reduce enamel demineralization in vitro

Objective: This study evaluated the effects of fluoride varnishes containing sodium trimetaphosphate (TMP) on bovine enamel demineralization in vitro.Material and methods: Enamel bovine discs were randomly assigned into six groups (n = 20/group): placebo, 2.5% NaF, 2.5% NaF/5% TMP, 5% NaF, 5% NaF/5% TMP, and a commercial formulation (Duraphat, 5% NaF). Varnishes were applied on all enamel discs and kept for 6 h. Loosely and firmly bound fluoride formed on/in enamel after treatment were analyzed in 10 discs from each group. The other 10 discs were subjected to a pH-cycling regimen for 7 days, and analyzed for surface (SH) and cross-sectional hardness (ΔKHN), as well as for loosely and firmly bound fluoride in/on enamel. Data were analyzed by analysis of variance (ANOVA) followed by Student–Newman–Keuls’ test (p < .05).Results: The lowest SH change and ΔKHN were observed for the 5%NaF/5%TMP varnish, which was significantly different from all the other groups. Both fluoridated varnishes containing TMP promoted significantly lower SH change and ΔKHN when compared with their counterparts without TMP. Loosely and firmly bound fluoride was significantly lower in groups treated with varnishes containing TMP.Conclusion: TMP and fluoride added to varnishes have a synergistic effect against enamel demineralization in vitro.

Nitisinone therapy shows beneficial effects on the chondrocytes and extracellular matrix in the osteoarthropathy of alkaptonuria

Purpose: Alkaptonuria is a rare autosomal recessive form of osteoarthropathy resulting from deficiency of homogentisate 1,2 dioxygenase (HGD) causing inability to metabolise the tyrosine metabolite; homogentisic acid (HGA). HGA levels in the body become elevated and show high affinity for collagenous tissues, primarily load bearing articular cartilages, where it polymerises and deposits as a dark pigment; this process is ochronosis. Over time ochronosis causes early onset joint arthropathy, mimicking osteoarthritis (OA) in presentation but progressing much more rapidly. Recently a therapy; Nitisinone has been shown to be effective in reducing the causative molecule; HGA, therefore potentially halting the arthropathy. This study aims to examine the effect of the drug Nitisinone on cell number, ochronosis and turnover of the extracellular matrix in an in vitro model of this disease whilst also comparing with the effects of IL-1β. Methods: Cultures of immortalised human chondrocytes C20/A4 were cultured in 24 well plates in DMEM containing HGA, IL-1β, Nitisinone or a combination of these reagents for up to 9 days. The rate of pigmentation was assessed using histology and counted as a number of pigment deposits/mm3, degradation and turnover of the matrix was assessed using DMMB assay and CTX-II ELISA on cell culture supernatants. Statistical analysis was performed using Graphpad Prism by ANOVA and Newman Keuls post-hoc analysis. Results: Cultures showed a significance decrease in the number of cells after 3 days of culture when comparing cultures containing HGA, compared to any of those which didn’t (p<0.001). By day 9 of culture similar significance decreases in cell number were seen when comparing cultures containing HGA and those without; Control vs; HGA and vs HGA + IL-1β (p<0.001). The rate of pigmentation in these cultures containing HGA showed no significant differences on day 3 or 6, but by day 9 the cultures containing HGA vs those which contained HGA in combination with Nitisinone showed a significantly higher amount of pigmentation. DMMB assay revealed a significant increase in the amount of GAG in supernatants of culture containing HGA alone vs control, IL-1β, Nitisinone or HGA+IL-1β+NTBC cultures. The cultures containing a combination of HGA+IL-1β vs HGA also showed a significant increase in the amount of GAG released. By day 9 the amount of GAG detectable was not significantly different between treatment groups, although the cultures containing HGA+IL+NTBC did show a decrease in the amount of GAG compared to HGA and HGA+IL-1β. CTX-II showed no significant differences in any treatment groups across 3, 6 or 9 days. Conclusions: This model is the first to test the effect of Nitisinone on the chondrocytes and their extracellular matrix in a model of Alkaptonuria; demonstrating the combined effect on pigmentation rate, cell number and the extracellular matrix. The effect of HGA on cell number shows an early effect on chondrocytes suggesting rapid decrease in chondrocytes at day 3. This is mirrored by loss of GAG from cultures early in the presence of HGA. Nitisinone shows a significant effect in decreasing the pigmentation rate, thus preventing the advancement of disease in these patients. Our results are the first to show the effect of Nitisinone on the release of GAG’s in this in vitro model and provide useful insight into how this drug may protect cartilage in these patients; this also shows some effect of protection of GAG in the presence of IL-1β alone. It also demonstrates that when HGA, the causative molecule in AKU is compared to one of the key mediators of OA; IL-1β, the effect on the cells and their matrix is more severe - giving potential insight into why the arthritis in AKU is more severe and rapidly progressing than that in OA.

Full in-vitro analyses of new-generation bulk fill dental composites cured by halogen light

The objective of this study was to investigate the full in-vitro analyses of new-generation bulk-fill dental composites cured by halogen light (HLG). Two types' four composites were studied: Surefill SDR (SDR) and Xtra Base (XB) as bulk-fill flowable materials; QuixFill (QF) and XtraFill (XF) as packable bulk-fill materials. Samples were prepared for each analysis and test by applying the same procedure, but with different diameters and thicknesses appropriate to the analysis and test requirements. Thermal properties were determined by thermogravimetric analysis (TG/DTG) and differential scanning calorimetry (DSC) analysis; the Vickers microhardness (VHN) was measured after 1, 7, 15 and 30days of storage in water. The degree of conversion values for the materials (DC, %) were immediately measured using near-infrared spectroscopy (FT-IR). The surface morphology of the composites was investigated by scanning electron microscopes (SEM) and atomic-force microscopy (AFM) analyses. The sorption and solubility measurements were also performed after 1, 7, 15 and 30days of storage in water. In addition to his, the data were statistically analyzed using one-way analysis of variance, and both the Newman Keuls and Tukey multiple comparison tests. The statistical significance level was established at p<0.05.According to the ISO 4049 standards, all the tested materials showed acceptable water sorption and solubility, and a halogen light source was an option to polymerize bulk-fill, resin-based dental composites.

EFFECTIVENESS OF COOPERATIVE LEARNING MODEL TYPE OF NUMBERED HEADS TOGETHER (NHT) WITH THINK PAIR SHARE (TPS) TYPE TOWARDS MATHEMATICS LEARNING OUTCOMES IN STUDENTS CLASS VIII IN SMP NEGERI 2 SLEMAN

The teacher-centered learning process makes the students less active and does not dare to express their opinion. It affects the result of students' mathematics learning. This research aims to determine the effectiveness of cooperative learning model NHT and TPS type compared with the Direct Learning type toward the result of students' mathematics learning. The type of study in this research is experimental research. The population of the research is all students in grade VIII SMP Negeri 2 Sleman in the academic year 2015/2016. The purposive sampling is used as a sampling technique, derived class VIII C as the experimental class I, class VIII D as the experimental class II and class VIII A as the control class. The data collection technique is documentation and tests. The instrument used is the test question of mathematics learning results. The prerequisite test analysis is the normality test and homogeneity test. Data analysis for hypothesis testing uses the F test continued Newman-Keuls Test Range. Research result with a significance level of and shows (1) There are differences in mathematics learning outcomes of students using cooperative learning model NHT, SMT type and the type of Learning Direct and to and (2) the results of students learning mathematics using cooperative learning model NHT and TPS type is better than the results of students' mathematics learning that uses the type of Direct Learning. It is indicated by the results of the Newman-Keuls Test Range that is the case I and then so acceptable means . In case II and then so rejected and ( then means . Whereas in the case of III and then so rejected and then means . So .

Comparative analysis of the mechanical properties of fiber and stainless steel multistranded wires used for lingual fixed retention

ObjectiveTo evaluate the effect of different resins used for the co-polymerization of EverStick fiber-reinforced fixed orthodontic retainer on its mechanical properties and to compare the mechanical properties of these configurations to commonly used multistrand wires. Materials and methodsTen 0.0175-in. WildCat (WC175), ten 0.0215-in. WildCat (WC215) three-strand twisted wires and thirty EverStick fibers were tested in this study. The EverStcik fibers were equally shared in three groups (n=10). The samples of first group (ESRE) were polymerized employing Stickresin (Light cure enamel adhesives), the second one (ESFT) employing Flow Tain (Light cured composite), whilst the specimens for the third group (ES) were not combined with resin. All samples were loaded in tensile up to fracture in a universal tensile testing machine and the modulus of elasticity, tensile strength and strain after fracture were recorded. The same groups were also tested employing Instrumented Indentation Testing (IIT) and Martens Hardness (HM), Indentation Modulus (EIT) and elastic index (ηIT) were determined. The results of tensile testing and IIT were statistically analyzed employing one way Anova and the Student Newman Keuls test (SNK) at a=0.05 level of significance. ResultsWC175 and WC215 showed higher modulus of elasticity and tensile strength but lower strain after fracture compared to Everstic groups. IIT illustrated significantly higher values for HM, EIT, and ηIT for WC groups compared to ESRE, ESFT and ES. ESFT showed higher HM and elastic index compared to ESRE and ES, a finding which is attributed to the fact the FlowTain is a filler-reinforce composite with higher hardness compared to unfilled resins. SignificanceMultistrand wires demonstrated higher values in mechanical properties compared to EverStick ones. The co-polymerization with difference resins does not affect the tensile properties of Everstic, however the use of a light cured composite has a beneficial effect on hardness.

Intracarotid Sodium Nitroprusside on Fifth Post Ischemic Stroke Day in Middle Cerebral Artery Occlusion Rat Model.

Ischemic stroke at later stages (>4.5 hour) have very few treatment options left. In those cases Nitric Oxide (NO) may provide promising results. NO is active in signaling pathways. Sodium Nitroprusside (SNP), a NO donor was tested earlier in rat Middle Cerebral Artery Occlusion (MCAO) model in early stages (5-60 minutes) and found useful but in delayed stroke cases (60-120 minutes) found useless. This was due to local inducible Nitric Oxide Synthase Enzyme (iNOS) and superoxide (causes destructive effect) formation which was skipped. To evaluate the effect of Intracarotid Sodium Nitroprusside (ICSNP) in MCAO rat model of ischemic stroke (I/R model) fifth post ischemic stroke day. A total of 24 Sprague Dawley rats, weighing 250 gm to 280 gm, at CDRI-Lucknow, India were used. Rats were divided in three groups. Group A (n=4) were taken as sham with standard procedure but without any injection on fifth day, Group B (n=8) as control with injection of saline on fifth day and Group C (n=12) received SNP at dose of 3 mcg/kg/minute given directly in internal carotid artery via External Carotid Artery (ECA) with a modified intraluminal stump technique as Ischemia/Reperfusion (I/R) in ipsilateral MCAO at intracarotid artery region as a single dose therapy on fifth day and then wound was closed. Waited for full recovery for two hours, then neurobehavioural assessment scores were noted. Thereafter, the brains were quickly removed and sliced at 2 mm intervals. Animals showing no sign of neurological deficit, were excluded from the study. Tested animals were compared with control animals for neurological deficit, percentage of infarction by 2,3,5-Triphenyl Tetrazolium Chloride (TTC) staining, nNOS expression and scores were summed up. The statistical analysis was done by Newman-Keuls test, Graph Pad prism (version.5.0) and p<0.05 was considered statistically significant. ICSNP group (Group C) showed a good reduction in the cerebral infarction of 53.42% as compared to control (Group B). Group A mean change in Newman-Keuls test and Graph Pad prism (version.5.0) was showing increase of 1.44 points/6.55%, compared to Group B decrease of 0.7 points. A 60% decrease in ischemic zone noted in Group A. The use of single dose ICSNP is beneficial (53.42%) in fifth post stroke day.