RESUMEN
Cisplatin is an effective antineoplastic agent, but its use is limited by its nephrotoxicity caused by the oxidative stress in tubular epithelium of nephrons. On the other hand, regular exercise provides beneficial adaptations in different tissues and organs. As with many drugs, dosing is extremely important to get the beneficial effects of exercise. Thus, we aimed to investigate the influence of exercise intensity and frequency on cisplatin-induced (20 mg/kg) renal damage in mice. Forty male Swiss mice were divided into five experimental groups (n=8 per group): 1) sedentary; 2) low-intensity forced swimming, three times per week; 3) high-intensity forced swimming, three times per week; 4) low-intensity forced swimming, five times per week; and 5) high-intensity forced swimming, five times per week. Body composition, renal structure, functional indicators (plasma urea), lipid peroxidation, antioxidant enzyme activity, expression of genes related to antioxidant defense, and inflammatory and apoptotic pathways were evaluated. Comparisons considered exercise intensity and frequency. High lipid peroxidation was observed in the sedentary group compared with trained mice, regardless of exercise intensity and frequency. Groups that trained three times per week showed more benefits, as reduced tubular necrosis, plasma urea, expression of CASP3 and Rela (NFkB subunit-p65) genes, and increased total glutathione peroxidase activity. No significant difference in Nfe2l2 (Nrf2) gene expression was observed between groups. Eight weeks of regular exercise training promoted nephroprotection against cisplatin-mediated oxidative injury. Exercise frequency was critical for nephroprotection.
Asunto(s)
Antioxidantes , Cisplatino , Animales , Antioxidantes/farmacología , Cisplatino/toxicidad , Peroxidación de Lípido , Masculino , Ratones , Estrés Oxidativo , Natación , UreaRESUMEN
Cisplatin is an effective antineoplastic agent, but its use is limited by its nephrotoxicity caused by the oxidative stress in tubular epithelium of nephrons. On the other hand, regular exercise provides beneficial adaptations in different tissues and organs. As with many drugs, dosing is extremely important to get the beneficial effects of exercise. Thus, we aimed to investigate the influence of exercise intensity and frequency on cisplatin-induced (20 mg/kg) renal damage in mice. Forty male Swiss mice were divided into five experimental groups (n=8 per group): 1) sedentary; 2) low-intensity forced swimming, three times per week; 3) high-intensity forced swimming, three times per week; 4) low-intensity forced swimming, five times per week; and 5) high-intensity forced swimming, five times per week. Body composition, renal structure, functional indicators (plasma urea), lipid peroxidation, antioxidant enzyme activity, expression of genes related to antioxidant defense, and inflammatory and apoptotic pathways were evaluated. Comparisons considered exercise intensity and frequency. High lipid peroxidation was observed in the sedentary group compared with trained mice, regardless of exercise intensity and frequency. Groups that trained three times per week showed more benefits, as reduced tubular necrosis, plasma urea, expression of CASP3 and Rela (NFkB subunit-p65) genes, and increased total glutathione peroxidase activity. No significant difference in Nfe2l2 (Nrf2) gene expression was observed between groups. Eight weeks of regular exercise training promoted nephroprotection against cisplatin-mediated oxidative injury. Exercise frequency was critical for nephroprotection.
RESUMEN
The sugarcane cystatin (CaneCPI-5) was recently cloned and showed strong binding force to dental enamel and protection against initial erosion. However, evaluations on its safety and efficacy in a situation closer to the clinical condition are necessary. In the present study we analyzed 1) the cytotoxicity of CaneCPI-5 on human gingival fibroblasts (HGFs); 2) the ability of CaneCPI-5 to reduce enamel erosion and erosion+abrasion in situ. In part 1, HGFs were treated with CaneCPI-5 (0.025, 0.05, 0.1, 0.5 or 1.0 mg/mL) or no treatment (control). The cytotoxicity was assessed after 60 s and 24 h by mitochondrial activity (MTT), confocal microscopy, and hematoxylin/eosin staining. In part 2, 15 volunteers participated in a double-blind crossover protocol consisting of 3 phases, according to the following treatments: 1) 0.1 mg/mL CaneCPI-5; 2) SnCl2/NaF/AmF (Elmex; positive control); 3) water (negative control). The volunteers wore an appliance containing 4 bovine enamel specimens for 5 d. Each day, the specimens were individually treated with 50 µL of the tested solutions per 60 s and then subjected to erosive challenges (0.1% citric acid, pH 2.5, for 90 s, 4 times per day). After the first and last erosive challenge each day, 2 samples were abraded (toothbrushing, 15 s). Enamel wear was measured by contact profilometry. One or two-way analysis of variance (ANOVA)/Tukey's or Sidak's tests (P < 0.05) were applied. Regardless of the concentration and the experimental time, CaneCPI-5 did not decrease the cell viability compared to the negative control (P < 0.05). Erosion+abrasion led to significantly greater wear compared to erosion only. For both conditions, the lowest wear was found for SnCl2 and CaneCPI-5, which did not differ significantly from each other, but showed significant protection when compared to the negative control. In conclusion, CaneCPI-5 is safe on HGFs and reduces enamel erosive wear to the same extent as a commercial solution used to control erosive tooth wear (ETW).
Asunto(s)
Cistatinas , Abrasión de los Dientes , Erosión de los Dientes , Desgaste de los Dientes , Animales , Bovinos , Estudios Cruzados , Esmalte Dental , Humanos , Erosión de los Dientes/inducido químicamente , Erosión de los Dientes/prevención & control , Cepillado DentalRESUMEN
OBJECTIVE: To compare the effect of TiF4 and NaF varnishes on demineralized bovine enamel under different cariogenic activities in situ. METHODS: Twenty subjects participated of this in situ study with 3 crossover phases (14days each), in which they wore palatal appliances containing demineralized bovine enamel samples (8 samples/appliance for phase) treated with TiF4, NaF (all with 2.45% F) or placebo varnish. The samples were subjected to different cariogenic conditions (1. absence of biofilm accumulation and sucrose exposure; 2. presence of biofilm and absence of sucrose exposure; 3. presence of biofilm and 20% sucrose exposure 4×/day; 4. presence of biofilm and 20% sucrose exposure 8×/day). All were exposed to fluoride dentifrice (2×/day). The mineral content and lesion depth were evaluated using transverse microradiography (TMR) and the data were subjected to RM two-way ANOVA/Bonferroni tests (p<0.05). RESULTS: TiF4 varnish significantly increased the remineralization of artificial carious lesions compared to placebo, regardless of the cariogenic activity. On the other hand, the remineralizing effect of NaF varnish was dependent on the cariogenic activity. For NaF, remineralization happened only in conditions 1 and 3 compared to placebo varnish (p<0.0001). NaF was unable to prevent further demineralization under biofilm accumulation and sucrose exposure 8×/day (condition 4). In the absence of fluoride treatment, demineralization happened in all conditions, except in the condition 1. CONCLUSION: Therefore, 4% TiF4 varnish was the only treatment able to improve enamel remineralization regardless of the cariogenic activity, while NaF varnish failed in preventing further demineralization under high cariogenic activity in situ. CLINICAL SIGNIFICANCE: 4% TiF4 varnish showed better remineralizing effect compared to NaF varnish, which was seen regardless of the cariogenic activity. This is a promising finding to support the indication of TiF4 in the clinic.
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Caries Dental/prevención & control , Esmalte Dental/efectos de los fármacos , Fluoruros Tópicos/uso terapéutico , Fluoruros/uso terapéutico , Fluoruro de Sodio/uso terapéutico , Titanio/uso terapéutico , Desmineralización Dental/prevención & control , Adulto , Animales , Biopelículas , Brasil , Bovinos , Estudios Cruzados , Esmalte Dental/química , Esmalte Dental/diagnóstico por imagen , Dentífricos/uso terapéutico , Método Doble Ciego , Fluoruros Tópicos/química , Humanos , Microrradiografía , Minerales , Sacarosa/efectos adversos , Remineralización Dental , Adulto JovenRESUMEN
The erosion-protective effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) is controversial. This study aimed to investigate the ability of CPP-ACP chewing gum to prevent a single event of erosive demineralization in situ. Bovine enamel blocks (n = 120) were randomly assigned to 3 phases according to the baseline surface hardness: phase I (PI) - chewing gum with CPP-ACP, phase II (PII) - chewing gum without CPP-ACP, and control phase (PIII) - salivary effect without stimulation (no gum). Nineteen volunteers participated in this study during 3 crossover phases of 2 h. In PI and PII, the volunteers wore intraoral palatal appliances for 120 min and chewed a unit of the corresponding chewing gum for the final 30 min. In the control phase the volunteers wore the appliance for 2 h, without chewing gum. Immediately after intraoral use, the appliances were extraorally immersed in a cola drink for 5 min to promote erosive demineralization. The percentage of surface hardness loss was calculated. The data were analyzed by ANOVA models and Tukey's test. Lower enamel hardness loss was found after the use of chewing gum with CPP-ACP (PI: 32.7%) and without CPP-ACP (PII: 33.5%) compared to the salivary effect without stimulation (PIII: 39.8%) (p < 0.05). There was no difference between PI and PII (p > 0.05). The results suggest that the use of chewing gum immediately before an erosive demineralization can diminish enamel hardness loss. However, the presence of CPP-ACP in the chewing gum cannot enhance this protective effect.
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Caseínas/farmacología , Goma de Mascar , Esmalte Dental/efectos de los fármacos , Desmineralización Dental/prevención & control , Erosión de los Dientes/prevención & control , Adolescente , Adulto , Análisis de Varianza , Bebidas Gaseosas/efectos adversos , Estudios Cruzados , Femenino , Dureza , Humanos , Masculino , Saliva/metabolismo , Método Simple Ciego , Factores de Tiempo , Adulto JovenRESUMEN
OBJECTIVES: Analyze the effect of varnishes containing xylitol compared to commercial fluoridated varnishes on the remineralization of artificial enamel caries lesions in situ. METHODS: Twenty subjects took part in this crossover, double-blind study performed in four phases of 5days each. Each subject worn palatal appliances containing four predemineralized bovine enamel specimens. Artificial caries lesions were produced by immersion in 30ml of lactic acid buffer containing 3mM CaCl2·2H2O, 3mM KH2PO4, 6µM tetraetil metil diphosphanate (pH 5.0) for 6days. The specimens in each subject were treated once with the following varnishes: 20% xylitol (experimental); Duofluorid™ (6% NaF, 6% CaF2), Duraphat™ (5% NaF, positive control) and placebo (no-F/xylitol, negative control). The varnishes were applied in a thin layer and removed after 6h. Fifteen subjects were able to finish all phases. The enamel alterations were quantified by surface hardness and transversal microradiography. The percentage of surface hardness recovery (%SHR), the integrated mineral loss and lesion depth were statistically analyzed by Friedmann and Dunn's tests test (p<0.05). RESULTS: Enamel surface remineralization was significantly increased by Duraphat™, Duofluorid™ and 20% xylitol formulations. Significant subsurface mineral remineralization could also be seen for the experimental and commercial varnishes, except for Duraphat™, when the parameter "lesion depth" was considered. CONCLUSIONS: 20% xylitol varnish seem to be a promising alternative to increase surface and subsurface remineralization of artificial caries lesions in situ. CLINICAL SIGNIFICANCE: effective vehicles are desirable for caries control. Xylitol varnishes seem to be promising alternatives to increase enamel remineralization in situ, which should be confirmed by clinical studies.
Asunto(s)
Caries Dental , Animales , Cariostáticos , Bovinos , Esmalte Dental , Método Doble Ciego , Fluoruros Tópicos , Remineralización Dental , XilitolRESUMEN
OBJECTIVES: Analyse the effect of varnishes containing xylitol alone or combined with fluoride on the remineralization of artificial enamel caries lesions in vitro. METHODS: Bovine enamel specimens were randomly allocated to 7 groups (n=15/group). Artificial caries lesions were produced by immersion in 30 mL of lactic acid buffer containing 3mM CaCl2·2H2O, 3mM KH2PO4, 6 µM tetraetil metil diphosphanate (pH 5.0) for 6 days. The enamel blocks were treated with the following varnishes: 10% xylitol; 20% xylitol; 10% xylitol plus F (5% NaF); 20% xylitol plus F (5% NaF); Duofluorid™ (6% NaF, 2.71% F+6% CaF2), Duraphat™ (5% NaF, positive control) and placebo (no-F/xylitol, negative control). The varnishes were applied in a thin layer and removed after 6h. The blocks were subjected to pH-cycles (demineralization-2h/remineralization-22 h during 8 days) and enamel alterations were quantified by surface hardness and transversal microradiography. The percentage of surface hardness recovery (%SHR), the integrated mineral loss and lesion depth were statistically analysed by ANOVA/Tukey's test or Kruskal-Wallis/Dunn's test (p<0.05). RESULTS: Enamel surface remineralization was significantly increased by Duraphat™, 10% xylitol plus F and 20% xylitol plus F formulations, while significant subsurface mineral remineralization could be seen only for enamel treated with Duraphat™, Duofluorid™ and 20% xylitol formulations. CONCLUSIONS: 20% xylitol varnishes seem to be promising alternatives to increase remineralization of artificial caries lesions. CLINICAL SIGNIFICANCE: effective vehicles are desirable for caries control. Xylitol varnishes seem to be promising alternatives to increase enamel remineralization in vitro, which should be confirmed by in situ and clinical studies.
Asunto(s)
Cariostáticos/uso terapéutico , Caries Dental/prevención & control , Esmalte Dental/efectos de los fármacos , Remineralización Dental/métodos , Xilitol/uso terapéutico , Animales , Cariostáticos/administración & dosificación , Bovinos , Esmalte Dental/química , Fluoruros Tópicos/uso terapéutico , Dureza , Concentración de Iones de Hidrógeno , Ácido Láctico/efectos adversos , Microrradiografía , Minerales/análisis , Placebos , Distribución Aleatoria , Saliva Artificial/química , Fluoruro de Sodio/uso terapéutico , Xilitol/administración & dosificaciónRESUMEN
The relationship between obesity and renal lesions, especially in low estrogen levels, has been less documented. The aim of this study was to assess the renal changes in diet-induced obesity in ovariectomized rats. Wistar rats were ovariectomized or sham-operated and divided into four groups: sham-operated rats fed a standard diet (SSD); ovariectomized rats fed a standard diet (OSD); sham-operated rats fed a high-fat diet (SHFD); ovariectomized rats fed a high-fat diet (OHFD). Body weight and blood pressure were measured weekly. The rats were killed 24 weeks after initiation of standard or high-fat diet treatment, the kidneys were removed for immunohistochemical and histological studies. Blood and urine samples were collected to quantify sodium, potassium and creatinine. OHFD rats presented increases in visceral adipose tissue, serum insulin levels, blood pressure and proteinuria, and a decrease in fractional excretion of sodium as well. Histological and morphometric studies showed focal alterations in the renal cortex. Expression of macrophages, lymphocytes, nuclear factor-kappa B (NF-kappaB), Proliferating Cell Nuclear Antigen (PCNA), angiotensin II (ANG II) and vimentin was greater in OHFD rats than in control rats. Thus, these results demonstrate that the high-fat diet in ovariectomized rats promoted renal function and structure changes, renal interstitial infiltration of mononuclear cells and increased expression of ANG II and NF-kappaB.
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Dieta Alta en Grasa/efectos adversos , Riñón/patología , Obesidad/patología , Ovariectomía , Angiotensina II/biosíntesis , Animales , Presión Sanguínea/fisiología , Peso Corporal , Ingestión de Energía , Femenino , Insulina/sangre , Macrófagos , FN-kappa B/biosíntesis , Infiltración Neutrófila , Ratas , Ratas Wistar , Factor de Necrosis Tumoral alfa/sangreRESUMEN
OBJECTIVE: This study analysed the anti-erosive effect of experimental solutions containing TiF4 and NaF. METHODS: Bovine enamel samples (n=15) were treated with: (1) commercial solution with SnCl2/NaF (Erosion Protection(®)); (2) experimental solution with 0.0815% TiF4; (3) 0.105% NaF; (4) 0.042% NaF + 0.049% TiF4; (5) 0.063% NaF + 0.036% TiF4 or (6) control. The samples were submitted to pH cycles and daily fluoride applications for seven days. The enamel wear was measured using a contact profilometer and analysed by ANOVA (p < 0.05). RESULTS: The best anti-erosive effect was found for experimental solution with 0.0815% TiF4 (99% reduction in enamel wear), followed by SnCl2/NaF (78%) and 0.049% TiF4 + 0.042% NaF solution (41%). CONCLUSIONS: The experimental solution containing a specific combination of TiF4 + NaF has the ability to partially reduce enamel erosion.
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Esmalte Dental/efectos de los fármacos , Fluoruros/farmacología , Antisépticos Bucales/farmacología , Fluoruro de Sodio/farmacología , Titanio/farmacología , Erosión de los Dientes/prevención & control , Animales , Bovinos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Incisivo , Compuestos de Estaño/farmacologíaRESUMEN
BACKGROUND: This in vitro study analysed the effect of different fluoride concentrations in acidic or neutral liquid dentifrices in protecting enamel and dentine from erosive and abrasive wear. METHODS: Bovine enamel and dentine specimens (n = 132) were randomly allocated to 11 groups (each n = 12): experimental liquid dentifrices with 550 ppm F, 1100 ppm F, 5000 ppm F or 0 ppm F/placebo (each at pH 4.5 and pH 7.0); and commercial dentifrices with 550 ppm F (Colgate Baby, pH 7.0), 1100 ppm F (Crest, pH 7.0) and 5000 ppm F (Duraphat, pH 7.0). The specimens were subjected to erosion for 90 seconds, 4 times/day, over 7 days. Immediately after the first and last erosion, the specimens were brushed for 15 seconds using one of the dentifrices. Tooth wear was measured profilometrically (µm) and analysed by ANOVA (p < 0.05). RESULTS: All fluoridated liquid dentifrices significantly reduced enamel wear compared to the placebo and commercial dentifrices. Only liquid dentifrices with 1100 and 5000 ppm F significantly reduced dentine wear compared to placebo dentifrice. The pH had no effect, but the consistency had a significant impact on the effect of dentifrices. CONCLUSIONS: Liquid dentifrices with high F concentration appear to be a good option to prevent tooth wear.
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Dentífricos/química , Fluoruros/farmacología , Abrasión de los Dientes/prevención & control , Erosión de los Dientes/prevención & control , Animales , Bovinos , Esmalte Dental/efectos de los fármacos , Humanos , Concentración de Iones de Hidrógeno , Lactante , Distribución AleatoriaRESUMEN
This study compared dentine demineralization induced by in vitro and in situ models, and correlated dentine surface hardness (SH), cross-sectional hardness (CSH) and mineral content by transverse microradiography (TMR). Bovine dentine specimens (n = 15/group) were demineralized in vitro with the following: MC gel (6% carboxymethylcellulose gel and 0.1 M lactic acid, pH 5.0, 14 days); buffer I (0.05 M acetic acid solution with calcium, phosphate and fluoride, pH 4.5, 7 days); buffer II (0.05 M acetic acid solution with calcium and phosphate, pH 5.0, 7 days), and TEMDP (0.05 M lactic acid with calcium, phosphate and tetraethyl methyl diphosphonate, pH 5.0, 7 days). In an in situ study, 11 volunteers wore palatal appliances containing 2 bovine dentine specimens, protected with a plastic mesh to allow biofilm development. The volunteers dripped a 20% sucrose solution on each specimen 4 times a day for 14 days. In vitro and in situ lesions were analyzed using TMR and statistically compared by ANOVA. TMR and CSH/SH were submitted to regression and correlation analysis (p < 0.05). The in situ model produced a deep lesion with a high R value, but with a thin surface layer. Regarding the in vitro models, MC gel produced only a shallow lesion, while buffers I and II as well as TEMDP induced a pronounced subsurface lesion with deep demineralization. The relationship between CSH and TMR was weak and not linear. The artificial dentine carious lesions induced by the different models differed significantly, which in turn might influence further de- and remineralization processes. Hardness analysis should not be interpreted with respect to dentine mineral loss.
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Dentina/patología , Proyectos de Investigación , Desmineralización Dental/inducido químicamente , Ácido Acético/efectos adversos , Anatomía Transversal , Animales , Biopelículas , Tampones (Química) , Calcio/química , Carboximetilcelulosa de Sodio/química , Cariogénicos/farmacología , Cariostáticos/química , Bovinos , Placa Dental/microbiología , Fluoruros/química , Dureza , Humanos , Concentración de Iones de Hidrógeno , Ácido Láctico/química , Microrradiografía , Minerales/análisis , Organofosfonatos/química , Fosfatos/química , Sacarosa/farmacología , Desmineralización Dental/patologíaRESUMEN
This proof-of-concept study assessed whether the reduction of the degradation of the demineralized organic matrix (DOM) by pre-treatment with protease inhibitors (PI) is effective against dentin matrix loss. Bovine dentin slices were demineralized with 0.87 M citric acid, pH 2.3, for 36 hrs. In sequence, specimens were treated or not (UT, untreated) for 1 min with gels containing epigallocatechin 3-gallate (EGCG, 400 µM), chlorhexidine (CHX, 0.012%), FeSO(4) (1 mM), NaF (1.23%), or no active compound (P, placebo). Specimens were then stored in artificial saliva (5 days, 37°C) with the addition of collagenase (Clostridium histolyticum, 100 U/mL). We analyzed collagen degradation by assaying hydroxyproline (HYP) in the incubation solutions (n = 5) and evaluated the dentin matrix loss by profilometry (n = 12). Data were analyzed by ANOVA and Tukey's test (p < 0.05). Treatment with gels containing EGCG, CHX, or FeSO(4) led to significantly lower HYP concentrations in solution and dentin matrix loss when compared with the other treatments. These results strongly suggest that the preventive effects of the PI tested against dentin erosion are due to their ability to reduce the degradation of the DOM.
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Cariostáticos/uso terapéutico , Colágeno/metabolismo , Colagenasas/metabolismo , Dentina/metabolismo , Inhibidores de Proteasas/uso terapéutico , Erosión de los Dientes/prevención & control , Análisis de Varianza , Animales , Proteínas Bacterianas/metabolismo , Catequina/análogos & derivados , Catequina/uso terapéutico , Bovinos , Clorhexidina/uso terapéutico , Dentina/ultraestructura , Matriz Extracelular/metabolismo , Compuestos Ferrosos/uso terapéutico , Fluoruro de Sodio/uso terapéutico , Desmineralización Dental/enzimología , Desmineralización Dental/prevención & control , Erosión de los Dientes/enzimologíaRESUMEN
We describe a case of proven donor transmission of carbapenem-resistant Acinetobacter baumannii, which resulted in severe infectious complications after lung transplantation. A single bla(OXA-23) positive strain, belonging to a new multilocus sequence type (ST231), was isolated from donor and recipient, who died 65 days after transplantation. This report highlights the current challenges associated with the potential transmission of multidrug-resistant infections through organ transplantation.
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Infecciones por Acinetobacter/transmisión , Acinetobacter baumannii/aislamiento & purificación , Bacteriemia/microbiología , Carbapenémicos/uso terapéutico , Trasplante de Pulmón/efectos adversos , Donantes de Tejidos , Resistencia betalactámica , Infecciones por Acinetobacter/diagnóstico , Infecciones por Acinetobacter/tratamiento farmacológico , Acinetobacter baumannii/efectos de los fármacos , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Resultado Fatal , Femenino , Humanos , Persona de Mediana Edad , Factores de TiempoRESUMEN
It has been suggested that fluoride products are able to reduce erosive tooth wear. Thus, the purpose of this in vitro study was to evaluate the effect of dentifrices with different fluoride concentrations as well as of a low-fluoridated dentifrice supplemented with trimetaphosphate (TMP) on enamel erosion and abrasion. One hundred twenty bovine enamel blocks were assigned to the following experimental dentifrices: placebo, 1,100 microg F/g, 500 microg F/g plus 3% TMP and 5,000 microg F/g. The groups of enamel blocks were additionally subdivided into conditions of erosion (ERO) and of erosion plus abrasion (ERO + ABR). For 7 days, the blocks were subjected to erosive challenges (immersion in Sprite 4 times a day for 5 min each time) followed by a remineralizing period (immersion in artificial saliva between erosive challenges for 2 h). After each erosive challenge, the blocks were exposed to slurries of the dentifrices (10 ml/sample for 15 s). Sixty of the blocks were additionally abraded by brushing using an electric toothbrush (15 s). The alterations of the enamel were quantified using the Knoop hardness test and profilometry (measurements in micrometers). The data were analyzed using a 2-way ANOVA test followed by a Bonferroni correction (p < 0.05). In in vitro conditions, the 5,000 microg F/g and 500 microg F/g plus 3% TMP dentifrices had a greater protective effect when compared with the 1,100 microg F/g dentifrice, under both ERO and ERO + ABR conditions. The results suggest that dentifrices alone are not capable of completely inhibiting tooth wear.
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Esmalte Dental/efectos de los fármacos , Dentífricos/administración & dosificación , Fluoruros/administración & dosificación , Abrasión de los Dientes/prevención & control , Erosión de los Dientes/prevención & control , Animales , Bebidas Gaseosas/efectos adversos , Bovinos , Esmalte Dental/patología , Dureza , Ensayo de Materiales , Placebos , Polifosfatos/administración & dosificación , Saliva Artificial/administración & dosificación , Factores de Tiempo , Abrasión de los Dientes/patología , Erosión de los Dientes/patología , Remineralización Dental , Cepillado Dental/efectos adversosRESUMEN
The aims of this study were: (1) to correlate surface (SH) and cross-sectional hardness (CSH) with microradiographic parameters of artificial enamel lesions; (2) to compare lesions prepared by different protocols. Fifty bovine enamel specimens were allocated by stratified randomisation according to their initial SH values to five groups and lesions produced by different methods: MC gel (methylcellulose gel/lactic acid, pH 4.6, 14 days); PA gel (polyacrylic acid/lactic acid/hydroxyapatite, pH 4.8, 16 h); MHDP (undersaturated lactate buffer/methyl diphosphonate, pH 5.0, 6 days); buffer (undersaturated acetate buffer/fluoride, pH 5.0, 16 h), and pH cycling (7 days). SH of the lesions (SH(1)) was measured. The specimens were longitudinally sectioned and transverse microradiography (TMR) and CSH measured at 10- to 220-microm depth from the surface. Overall, there was a medium correlation but non-linear and variable relationship between mineral content and radicalCSH. radicalSH(1) was weakly to moderately correlated with surface layer properties, weakly correlated with lesion depth but uncorrelated with integrated mineral loss. MHDP lesions showed the highest subsurface mineral loss, followed by pH cycling, buffer, PA gel and MC gel lesions. The conclusions were: (1) CSH, as an alternative to TMR, does not estimate mineral content very accurately, but gives information about mechanical properties of lesions; (2) SH should not be used to analyse lesions; (3) artificial caries lesions produced by the protocols differ, especially considering the method of analysis.
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Cariogénicos/efectos adversos , Caries Dental/patología , Esmalte Dental/patología , Acetatos/efectos adversos , Resinas Acrílicas/efectos adversos , Anatomía Transversal , Animales , Apatitas/farmacología , Tampones (Química) , Fosfatos de Calcio/farmacología , Cariostáticos/farmacología , Bovinos , Caries Dental/metabolismo , Esmalte Dental/química , Difosfonatos/efectos adversos , Durapatita/efectos adversos , Fluoruros/farmacología , Geles , Dureza , Concentración de Iones de Hidrógeno , Ácido Láctico/efectos adversos , Metilcelulosa/efectos adversos , Microrradiografía , Distribución Aleatoria , Soluciones , Factores de Tiempo , Desmineralización Dental/patología , Remineralización DentalRESUMEN
This study evaluated, by cross-sectional hardness (CSH), enamel maturation at different depths in sound human teeth at different posteruptive ages (12 per age group): unerupted (molars; control), 2-3 years (premolars), 4-10 years (premolars) and >10 years (molars). Cross-sectional Knoop hardness was measured at 10, 30, 50, 70, 90, 110, 220 and 330 mm depth from the surface. The data were subjected to two-way ANOVA followed by Bonferroni's pairwise tests (a = 0.05). The CSH significantly increased with posteruptive age, indicating that the time of exposure in the oral cavity might result in deep enamel maturation.
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Esmalte Dental/anatomía & histología , Erupción Dental/fisiología , Factores de Edad , Anatomía Transversal , Diente Premolar/anatomía & histología , Niño , Preescolar , Esmalte Dental/crecimiento & desarrollo , Dureza , Humanos , Diente Molar/anatomía & histología , Proyectos Piloto , Diente no Erupcionado/anatomía & histologíaRESUMEN
Acidic soft drinks are potentially erosive for dental hard tissues. This in vitro study evaluated the effect of calcium, fluoride, iron and phosphate, supplemented alone or in combination to a commercial citric acid-based carbonated beverage on dental erosion. Ninety enamel samples (4 x 4 x 3 mm) were randomly allocated to nine groups (n = 10): G1-pure beverage (control); G2-with 1 mM Ca; G3-with 0.047 mM F; G4-with 1 mM Fe; G5-with 1 mM P; G6 - with 1 mM Ca and 0.047 mM F; G7-with 1 mM Ca and 1 mM P; G8-with 1 mM Fe and 0.047 mM F; and G9-with 1 mM Ca, 1 mM P, 0.047 mM F and 1.0 mM Fe. The samples were subjected to six pH cycles over a 24-h period. In each cycle, the samples were immersed in pure or modified beverage (1 min) and in artificial saliva (59 min). During the remaining period (18 h), the samples were maintained in artificial saliva. Enamel loss was assessed by profilometry (microm). Data were tested using ANOVA and Tukey's tests (p < 0.05). Highest enamel losses were observed in the control group (G1) and in the groups containing Fe (G4 and G8). The groups containing Ca (G2 and G6) showed significantly less wear compared to control. In conclusion, the modification of an erosive soft drink with low concentrations of Ca with or without F may reduced its erosive potential.
Asunto(s)
Calcio de la Dieta/efectos adversos , Bebidas Gaseosas/efectos adversos , Esmalte Dental/efectos de los fármacos , Fluoruros/administración & dosificación , Hierro de la Dieta/efectos adversos , Fosfatos/administración & dosificación , Análisis de Varianza , Animales , Bovinos , Solubilidad del Esmalte Dental/efectos de los fármacos , Dureza , Concentración de Iones de Hidrógeno , Distribución Aleatoria , Saliva Artificial , Erosión de los Dientes/prevención & controlRESUMEN
O alto polimorfismo encontrado no lócus do gene da αS1-caseína em caprinos, classificado em quatro níveis de expressão - alto, médio, baixo e nulo -, está associado à produção de 3,6; 1,6; 0,6 e 0g/L/alelo, respectivamente. O estudo foi realizado para investigar possíveis variações na produção de leite e seus constituintes, no perfil de caseínas e na lipólise da gordura. Quarenta e quatro cabras foram distribuídas em cinco genótipos: dois homozigotos, um para alta (AA) e outro para produção intermediária (EE), e três heterozigotos chamados AE, AF e EF, para αs1-caseína. Para a lipólise, o leite foi subamostrado em quatro alíquotas que sofreram tratamento térmico no momento da ordenha e após 24h de resfriamento. Diferenças entre genótipos foram observadas para a produção de caseína e de suas frações. As demais variáveis não diferiram entre genótipos. O genótipo AA apresentou os maiores conteúdos de caseína (28,6g/L) e de αS1-cn (22,3 por cento). Os demais genótipos apresentaram média de 20,4g/L. Os grupos AE e AF apresentaram média de 12,1, EE-10,1 e EF-9,1 por cento de αS1-cn. O resfriamento do leite por 24 horas aumentou a taxa de lipólise no leite. A genotipagem das cabras para αS1-cn pode ser usada como ferramenta de seleção com objetivo de obter produtos lácteos com distintos perfis de proteínas.
A high polymorphism is found in the locus of goat αS1-casein gene and it is classified in four levels of expression, named high, medium, and low, associated with production of 3.6, 1.6, 0.6, and 0 g/L/allele, respectively. The study was conducted to investigate possible variations on milk yield and components, profile of casein, and lipolysis of fat. Forty-four goats were assigned to five distinct genotypes as two homozygous, one for high (AA) and the other for intermediate yield (EE); and three heterozygous named AE, AF, and EF for the αs1-casein. For lipolysis, milk was sampled in four aliquots which were treated soon after milking and 24 hours after cooling. Differences were observed for both casein yield and its fractions. No difference was found for other variables. The AA genotype presented the higher content of both casein (28.6g/L) and αS1-cn (22.3 percent). Other genotypes averaged 20.4g/L for casein content. Values of αS1-cn were 12.1 percent for heterozygous and 10.1 and 9.1 percent for both EE and EF genotype respectively. Cooling the milk for 24 hours increased the rate of lipolysis. Genotyping goats for the αS1-cn can be used as a tool for selecting animal targeting milk products with distinct profiles of proteins.
Asunto(s)
Animales , Femenino , Caseínas/análisis , Lipólisis , Leche/química , Polimorfismo Genético , Genotipo , CabrasRESUMEN
O alto polimorfismo encontrado no lócus do gene da αS1-caseína em caprinos, classificado em quatro níveis de expressão - alto, médio, baixo e nulo -, está associado à produção de 3,6; 1,6; 0,6 e 0g/L/alelo, respectivamente. O estudo foi realizado para investigar possíveis variações na produção de leite e seus constituintes, no perfil de caseínas e na lipólise da gordura. Quarenta e quatro cabras foram distribuídas em cinco genótipos: dois homozigotos, um para alta (AA) e outro para produção intermediária (EE), e três heterozigotos chamados AE, AF e EF, para αs1-caseína. Para a lipólise, o leite foi subamostrado em quatro alíquotas que sofreram tratamento térmico no momento da ordenha e após 24h de resfriamento. Diferenças entre genótipos foram observadas para a produção de caseína e de suas frações. As demais variáveis não diferiram entre genótipos. O genótipo AA apresentou os maiores conteúdos de caseína (28,6g/L) e de αS1-cn (22,3 por cento). Os demais genótipos apresentaram média de 20,4g/L. Os grupos AE e AF apresentaram média de 12,1, EE-10,1 e EF-9,1 por cento de αS1-cn. O resfriamento do leite por 24 horas aumentou a taxa de lipólise no leite. A genotipagem das cabras para αS1-cn pode ser usada como ferramenta de seleção com objetivo de obter produtos lácteos com distintos perfis de proteínas.(AU)
A high polymorphism is found in the locus of goat αS1-casein gene and it is classified in four levels of expression, named high, medium, and low, associated with production of 3.6, 1.6, 0.6, and 0 g/L/allele, respectively. The study was conducted to investigate possible variations on milk yield and components, profile of casein, and lipolysis of fat. Forty-four goats were assigned to five distinct genotypes as two homozygous, one for high (AA) and the other for intermediate yield (EE); and three heterozygous named AE, AF, and EF for the αs1-casein. For lipolysis, milk was sampled in four aliquots which were treated soon after milking and 24 hours after cooling. Differences were observed for both casein yield and its fractions. No difference was found for other variables. The AA genotype presented the higher content of both casein (28.6g/L) and αS1-cn (22.3 percent). Other genotypes averaged 20.4g/L for casein content. Values of αS1-cn were 12.1 percent for heterozygous and 10.1 and 9.1 percent for both EE and EF genotype respectively. Cooling the milk for 24 hours increased the rate of lipolysis. Genotyping goats for the αS1-cn can be used as a tool for selecting animal targeting milk products with distinct profiles of proteins.(AU)
Asunto(s)
Animales , Femenino , Polimorfismo Genético , Lipólisis , Caseínas/análisis , Leche/química , Genotipo , CabrasRESUMEN
This in vitro study evaluated the effect of a prolonged erosive pH cycling on the superficial microhardness change (SMHC) and the erosive wear of different restorative materials. Eighty enamel specimens with prepared cavities of 1.5 x 1.5 mm were randomly divided into eight groups according to the restorative materials used for the fillings (RMGI - resin-modified glass-ionomer, CGI - conventional glass-ionomer, CR- composite resin, A - amalgam) and immersion media used (ERO - erosive medium or SAL - artificial saliva). During 35 days, half of the specimens were immersed in a cola drink (ERO), for 5 min, three times a day, and they remained in SAL between the erosive cycles. The other half of the specimens was immersed in SAL only, for the entire experimental period (control). Data were tested for significant differences by anova and Tukey's tests (P < 0.05). Scanning electron microscopy images were made to illustrate the enamel erosive wear and restorative materials alterations. The mean SMHC (%) and mean erosive wear (mum) of the materials were: RMGI-ERO (30/0.5); CGI-ERO (37/0.5); CR-ERO (-0.3/0.3); A-ERO (-4/0.3); RMGI-SAL (4/0.4); CGI-SAL (-6/0.4); CR-SAL (-3/0.2) and A-SAL (2/0.4). Scanning electron microscopy images showed pronounced enamel erosive wear on groups submitted to erosive pH cycling when compared with groups maintained in saliva. In conclusion, the prolonged pH cycling promoted significantly higher alterations (SMHC and erosive wear) on the glass-ionomer cements than the CR and amalgam.