RESUMEN
OBJECTIVES: To evaluate the volume and depth of enamel loss promoted by 37.5% and 7.5% hydrogen peroxide (HP) gels, and quantify the loss of calcium (Ca) and phosphate (P) ions by using ion chromatography (IC) analysis after bleaching. METHODS: Sixty bovine enamel specimens were randomly divided into three groups: Control - no bleaching gel; HP37.5%, application of HP 37.5% for 45 minutes for 14 days; and HP7.5%, application of HP 7.5% for 3 applications of 8 minutes. The surface analysis (n=5) was performed using a scanning electron microscope (SEM) and dispersive energy system (EDS) to calcium and phosphorus dosage. The micro-CT was used for the enamel loss analysis (n=5). IC was used to analyze extracted Ca and P (n=10). Data were analyzed by one-way ANOVA and two-way repeated measures ANOVA, followed by Tukey and Dunnett's tests (α=0.05). RESULTS: Significantly higher volume and depth of enamel loss were found for bleached groups compared with the control group. HP7.5% had significantly higher enamel change than HP37.5%. SEM showed higher enamel porosity for HP37.5% and HP7.5% compared to control. The IC demonstrated a significant increase of Ca incorporated into the gel, however, only HP7.5% had a higher P presence than the control group. The HP7.5% showed higher Ca and P ion exchange than HP37.5% (p<0.001). CONCLUSION: HP37.5% and HP7.5%, caused enamel mineral changes compared with the control group. The IC method was demonstrated to be an effective methodology for detecting enamel mineral loss by the bleaching gel.
Asunto(s)
Blanqueadores Dentales , Blanqueamiento de Dientes , Animales , Bovinos , Calcio , Blanqueamiento de Dientes/métodos , Esmalte Dental , Microtomografía por Rayos X , Peróxido de Hidrógeno/química , Minerales , Fosfatos , GelesRESUMEN
Ocular toxoplasmosis is the major cause of infectious posterior uveitis worldwide, inducing visual field defect and/or blindness. Despite the severity of this disease, an effective treatment is still lacking. In this study, spiramycin-loaded PLGA implants were developed aiming at the treatment of ocular toxoplasmosis. Implants were manufactured by a hot-molding technique, characterized by Fourier Transform Infrared Spectroscopy, X-Ray Diffraction, Differential Scanning Calorimetry, Scanning Electron Microscopy; evaluated in terms of ocular biocompatibility by immunofluorescence, flow cytometry, cell migration, Hen's egg test-chorioallantoic membrane (HET-CAM) irritation test; and investigated in terms of in vitro efficacy against Toxoplasma gondii . Characterization techniques indicated that spiramycin was dispersed into the polymeric chains and both substances preserved their physical structures in implants. The HET-CAM test indicated that implants did not induce hemorrhage or coagulation, being non-irritant to the CAM. ARPE-19 cells showed viability by MTT assay, and normality in cell cycle kinetics and morphology, without stimulating cell death by apoptosis. Finally, they were highly effective against intracellular parasites without inducing human retinal pigment epithelial cell death. In conclusion, spiramycin-loaded PLGA implants represent a promising therapeutic alternative for the local treatment of ocular toxoplasmosis.
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Sistemas de Liberación de Medicamentos/métodos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Espiramicina/administración & dosificación , Toxoplasmosis Ocular/tratamiento farmacológico , Animales , Técnicas de Cultivo de Célula , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Pollos , Membrana Corioalantoides , Células Epiteliales , Humanos , Microscopía Electrónica de Rastreo , Epitelio Pigmentado de la Retina , Espiramicina/uso terapéutico , Toxoplasma/efectos de los fármacosRESUMEN
AIM: To analyse the cytotoxicity, colour change and radiopacity of MTA Flow (MTA), UltraCal XS (UC) and Bio-C Temp (BT). METHODOLOGY: Human dental pulp cells (hDPCs) stimulated with lipopolysaccharide (LPS) were placed in contact with several dilutions of culture media previously exposed to the experimental materials and tested for cell viability using MTT. Bovine teeth were prepared to simulate an open apex and to mimic extensive crown fracture. The roots were filled with a mixture of agar and blood, and the materials placed over this mixture. The control group consisted of teeth filled only with agar and blood. Colour assessment analyses were performed before and immediately after material insertion and repeated at 30, 45 and 60 days using a spectrophotometer. The total colour change (ΔEab , ΔE00 and whiteness index (WI)) was calculated based on the CIELAB colour space. Digital radiographs were acquired for radiopacity analysis. Cell viability was analysed by one-way anova, whilst differences in colour parameters (ΔEab , ΔE00 and WI) were assessed by two-way repeated measures anova (α = 0.05). Tukey's test was used to compare the experimental groups, and Dunnett's test was used to compare the experimental groups with the control group. RESULTS: MTA, UC and BT had similar cell viability to that of the control group (DMEM) (P > 0.05), except for the BT group at the 1 : 1 and 1 : 2 dilutions, which had significantly lower viability (P < 0.001). All materials were associated with discoloration values greater than what is considered to be the acceptable threshold, and BT resulted in less or similar tooth colour change than MTA and UC, respectively. Decreasing radiopacity over time was observed only in the MTA group (P = 0.007). Lower values of radiopacity were found in the BT group compared with the UC and MTA groups (P < 0.001). CONCLUSIONS: The new bioceramic material (BT) had acceptable cell viability, similar to that of MTA and UC at the highest dilutions, and BT resulted in less tooth colour change than MTA and UC. Despite its lower radiopacity, BT was identified radiographically.
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Materiales de Obturación del Conducto Radicular , Decoloración de Dientes , Compuestos de Aluminio , Animales , Compuestos de Calcio , Bovinos , Supervivencia Celular , Combinación de Medicamentos , Humanos , Óxidos , Endodoncia Regenerativa , SilicatosRESUMEN
Oxidative stress has been correlated with pathologies that impair the performance of athlete horses. The aim of this study was to assess the effects of supplementation with a mixture of polyunsaturated oil and vitamin E on the antioxidant and haematological biomarkers of horses. Horses under maintenance care (n = 6) and horses in training (n = 10) received 100 and 300 ml of the oil mixture respectively. Supplementation was provided for a period of 8 weeks, together with isocaloric inclusion. Blood samples were collected at three time periods (pretest, after 4 weeks and after 8 weeks) to analyse the following: the red blood cell count (RBCc); haemoglobin (Hb); haematocrit (HT); leucocytes; lymphocytes; platelets; the mean corpuscular volume (MCV); the mean corpuscular haemoglobin concentration (MCHC); the standard deviation of the red blood cell distribution width (RDW-SD); the coefficient of variation of the red blood cell distribution width (RDW-CV); glutathione peroxidase (GPx); superoxide dismutase (SOD); uric acid (UrAc); total plasma proteins (TPP); and creatine kinase (CK). After the 8 weeks of supplementation, animals under maintenance care exhibited significant increases in SOD, UrAc, the white blood cell count (WBCc), the RDW-SD and the RDW-CV (p < 0.05). The animals in training exhibited increases in GPx, SOD and UrAc (p < 0.05). In conclusion, supplementation with polyunsaturated oil and vitamin E increases blood antioxidants among animals under maintenance and in training, with different trends, while contributing to the fight against oxidative stress in each group analysed.
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Antioxidantes/metabolismo , Ácidos Grasos Insaturados/farmacología , Caballos/sangre , Vitamina E/farmacología , Animales , Biomarcadores/sangre , Suplementos Dietéticos , Ácidos Grasos Insaturados/administración & dosificación , Femenino , Masculino , Estrés OxidativoRESUMEN
Intraplantar injection of staphylococcal enterotoxin B induces long-lasting oedema mediated by both cyclooxygenase and lipoxygenase products as well as by neuropeptides from sensory nerves. This study was undertaken to further clarify the role of peripheral primary afferent sensory nerves in staphylococcal enterotoxin B (25 microg/paw)-induced plasma extravasation and oedema formation. The tachykinin NK(1) receptor antagonist (S)-1-[2-[3-(3, 4-dichlorophenyl)-1 (3-isopropoxyphenylacetyl)piperidin-3-yl] ethyl]-4-phenyl-1 azoniabicyclo [2.2.2]octane cloride (SR140333; 120 nmol/kg, s.c.+120 nmol/kg, i.v.) significantly inhibited plasma exudation and paw oedema evoked by staphylococcal enterotoxin B. The tachykinin NK(2) receptor antagonist (S)-N-methyl-N[4-(4-acetylamino-4-phenyl piperidino)-2-(3, 4-dichlorophenyl)butyl]-benzamide (SR48968) had no effect on the staphylococcal enterotoxin B-induced responses. The bradykinin B(2) receptor antagonist D-Arg-[Hyp(3),Thi(5),D-Tic(7),Oic(8)]bradykinin (Hoe 140; 400 nmol/kg, i.v.) significantly reduced staphylococcal enterotoxin B-induced responses. The magnitude of the inhibition observed with Hoe 140 alone was similar to that caused by concomitant treatment of animals with SR140333 and Hoe 140, suggesting that there is a final common pathway. Additionally, SR140333 given alone reduced bradykinin (3 nmol/paw)-induced paw oedema. The vanilloid receptor antagonist N-[2-(4-chlorophenyl) ethyl]-1,3,4,5-tetrahydro-7, 8-dihydroxy-2H-2-benzazepine-2-carbothioamide (capsazepine; 100 micromol/kg) significantly reduced staphylococcal enterotoxin B-induced responses. The 5-HT receptor antagonist methysergide (10 mg/kg, i.v.) and the histamine H(1) receptor antagonist mepyramine (10 mg/kg, i.v.) produced a significant reduction in paw oedema whereas plasma exudation was reduced only by methysergide. In diabetic mice, exudation and oedema evoked by staphylococcal enterotoxin B were markedly reduced. Acute administration of insulin (20 UI/kg, s.c., 30 min before) did not restore the increased permeability induced by staphylococcal enterotoxin B. We conclude that plasma exudation and paw oedema in response to staphylococcal enterotoxin B are a consequence of a complex neurogenic response involving direct activation of vanilloid receptors on sensory nerves, release of kinins and subsequent activation of bradykinin B(2) receptors at a prejunctional level, and direct or indirect degranulation of mast cells.
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Bradiquinina/análogos & derivados , Permeabilidad Capilar/efectos de los fármacos , Capsaicina/análogos & derivados , Edema/fisiopatología , Enterotoxinas/farmacología , Cininas/efectos de los fármacos , Mastocitos/efectos de los fármacos , Neuronas Aferentes/efectos de los fármacos , Animales , Benzamidas/farmacología , Bradiquinina/farmacología , Capsaicina/farmacología , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Edema/inducido químicamente , Edema/metabolismo , Miembro Posterior/efectos de los fármacos , Miembro Posterior/patología , Cininas/metabolismo , Masculino , Mastocitos/citología , Ratones , Antagonistas del Receptor de Neuroquinina-1 , Neuronas Aferentes/metabolismo , Piperidinas/farmacología , Pirilamina/farmacología , Quinuclidinas/farmacología , Receptores de Neuroquinina-2/antagonistas & inhibidoresRESUMEN
OBJECTIVE: The purpose of this study was to estimate the secular trend/change in the height of young males born in the city of S. Paulo between 1950 and 1976 and measured in the year they turn 18 years. METHODS: A random and representative sample (6,942 individuals) was evaluated in military draft. Statistical analyses included Shapiro-Wilk test for normality of height distribution in each birth cohort, and linear regression analysis for trend on heights. RESULTS/CONCLUSIONS: Stature has increased 3.42 centimeters during the 27 years covered by the study (1.26 cm/decade). The trend was not linear: in the 50s, there was a statistically significant increase (0.84 cm/decade); in the 60s, a smaller but non-significant increase (0.5 cm/decade) was seen; in the period of 1970-76, a greater increase in heights (2.9 cm/decade) was observed. The secular change rate observed was comparable to the rate seen in other countries. The most recent birth cohorts (1975 and 1976) achieved the higher statures in the study (approximately 175 cm). Despite these height increments, deficits of 1.8 e 6.2 cm were seen when the taller cohorts of the study were compared to American young males born in 1961 (NCHS) and Dutch men born in 1972. If there won't be any changes in the accelerated rates of the 70s, young people of São Paulo may overcome these deficits in about one or three decades.
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Estatura/fisiología , Adolescente , Antropometría , Brasil , Humanos , Modelos Lineales , Masculino , Personal MilitarRESUMEN
This study investigates the housing conditions and deforesting in Caconde and São José do Rio Pardo, neighbouring towns located in the northeastern region of the State of São Paulo, Brazil. These localities have had different dwelling infestation rates by Panstrongylus megistus and they also show distinct socioeconomic development. The housing conditions were studied by the analysis of data collected during the 1970's by the Superintendência de Controle de Endemias (SUCEN), a government agency. Aerial photographs taken during flights performed by the Agricultural Department of the State were used to analyse the deforesting. The socioeconomic analysis was based on Agricultural Census and interview with agronomic officials. The study showed more precarious housing conditions in Caconde than in São José do Rio Pardo. It was related to lower socioeconomic development in Caconde, confirming a trend showed by previous studies. The deforesting was more intense in São José, where socioeconomic development has been higher and the infestation rates were lower, what demonstrates opposite behaviour between the two determinants in these towns. The links between deforesting and higher socioeconomic development can also be showed by the relation between productive activity and destruction of the natural agricultural covering. It is emphasized that the tendency of opposite effect of the deforesting did not change the final result, that is, the confrontation of these determinant forces resulted in higher infestation rates in Caconde than in São José do Rio Pardo. The existence of these opposite trends between the determinants disclosed therefore more complexity in the infestation process of P. megistus, although the final result was not reverted changed.