RESUMO
The methanolic extract of Buchholzia coriacea seeds (MEBC) has been reported to induce male reproductive toxicity by decreasing sperm parameters and fertility index. To elucidate the possible mechanism(s), the effects of graded doses of MEBC on sex hormones and sperm profile were investigated in this study. The MEBC (e.g., 50, 200, 400, and 600 mg/kg) was administered daily (p.o.) to male Wistar rats for 6 weeks, while a concurrent control group received distilled water (vehicle). Then, the animals were sacrificed under sodium pentobarbital anaesthesia. Weights of organs were recorded, and the sperm profile was determined microscopically. Testosterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH) were assayed from the obtained serum using the ELISA technique. Sperm motility was significantly reduced by MEBC (i.e., 50 and 200 mg/kg), and sperm count reduced in all treated groups in a dose-dependent manner compared with that of the control. Serum testosterone, LH, and FSH decreased in treated rats. A histopathological examination of testes showed a considerable depletion and necrosis of the epithelium of seminiferous tubules. The result suggests that Buchholzia coriacea seeds induce male reproductive toxicity by suppressing the pituitary-gonadal axis.
Assuntos
Animais , Masculino , Ratos , Espermatozoides/efeitos dos fármacos , Cola , Capparaceae/classificação , Contagem de Espermatozoides/instrumentação , Motilidade dos Espermatozoides , Ensaio de Imunoadsorção Enzimática/instrumentação , Hormônio Luteinizante/análise , Fertilidade , Hormônio Foliculoestimulante/análiseRESUMO
Abstract Objective: To evaluate the effect of immersion and acid challenge with cola drink on color change (ΔE), Vickers hardness (VHN) and surface roughness (Ra) of artificial acrylic resin teeth. Material and Methods: The artificial teeth were divided into 6 groups (n= 8): TC (Trilux/Control), BC (Biotone/Control), TAC (Trilux/Acid challenge), BAC (Biotone/Acid challenge), TI (Trilux/Immersion) and BI (Biotone/Immersion). The teeth were embedded in acrylic resin and the labial side was serially polished to provide appropriate flat surface. The samples of TC, BC, TI, BI groups were immersed in artificial saliva and cola drink (coke) for 7 days, respectively. The acid challenge was performed with immersion of samples in coke for 5 min, and subsequently immersion in artificial saliva for 2h. This cycle was repeated at 4 times/day, during 7 days. The tests of VHN, ΔE and Ra were analyzed before and after the challenge and immersion groups. Data was analyzed by ANOVA, Tukey and T test (α = 0.05). Results: There was no difference in Ra values between groups after treatments. However, there was a decrease in VHN for all groups. BI (19.2 ± 0.3) presented significantly lower hardness than BAC (19.5 ± 0.9) and BC (20.2 ± 0.5). Groups BI (2.18 ± 0.41) and TI (1.50 ± 0.43) had statistically higher ΔE compared to the other groups. Conclusion: The hardness of resin teeth decreased after acid challenges, but the roughness surface was not affected. The color was more affected by the times of exposure in cola beverage and remineralization in artificial saliva, which were associated to the material degradation (AU).
Assuntos
Dente Artificial , Resinas Acrílicas/química , Técnicas In Vitro/métodos , Prótese Dentária , Bebidas , Brasil , Análise de Variância , Cola/química , Testes de Dureza/instrumentaçãoRESUMO
INTRODUCTION: The resin of Cola nitida is used in western Cameroon as incense for spiritual protection and during ritual ceremonies. This plant secretion has never been investigated although previous chemical and biological studies on other resins have drawn many attentions. OBJECTIVE: The resin fractions which revealed inhibitory effect on nitric oxide (NO) and tumour necrosis factor alpha (TNF-α) released by lipopolysaccharide (LPS)-activated J774 macrophage as well as on intracellular forms of Leishmania amazonensis and Trypanosoma cruzi amastigote were chemically characterised. Moreover, their antiparasitic activities were compared to those of semi-synthetic triterpenes. METHODOLOGY: The anti-inflammatory activity was evaluated by measuring the nitrite production and the TNF-α concentration in the supernatants of LPS-activated macrophages by antigen capture enzyme-linked immunosorbent assay. Moreover, the antiparasitic assay was performed by infecting the host cells (THP-1) in a ratio parasite/cell 10:1 (L. amazonensis) and 2:1 (T. cruzi) and then exposed to the samples. The resin was separated in vacuo by liquid chromatography because of its sticky behaviour and the chemical profiles of the obtained fractions (F1-F4) were established by dereplication based on UPLC-ESI-MS2 data while semi-synthetic triterpenes were prepared from α-amyrin by oxidation reactions. RESULTS: Fractions F1-F4 inhibited NO and TNF-α almost similarly. However, only F1, F3 and F4 showed promising antiparasitic activities while F2 was moderately active against both parasites. Hence, F1-F4 were exclusively composed of pentacyclic triterpenes bearing oleanane and ursane skeletons. Semi-synthetic compounds revealed no to moderate antiparasitic activity compared to the fractions. CONCLUSION: Although it will be difficult to prove the interaction resin-spirit, interesting bioactivities were found in the resin fractions.
Assuntos
Cromatografia Líquida/métodos , Cola/química , Leishmania/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Espectrometria de Massas/métodos , Trypanosoma cruzi/efeitos dos fármacos , Animais , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Óxido Nítrico/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Resinas Vegetais/química , Fator de Necrose Tumoral alfa/metabolismoRESUMO
We report experimental evidence confirming renal histopathology, proinflammatory mediators, and oxidative metabolism induced by cola drinking. Male Wistar rats drank ad libitum regular cola (C, n = 12) or tap water (W, n = 12). Measures. Body weight, nutritional data, plasma glucose, cholesterol fractions, TG, urea, creatinine, coenzyme Q10, SBP, and echocardiograms (0 mo and 6 mo). At 6 months euthanasia was performed. Kidneys were processed for histopathology and immunohistochemistry (semiquantitative). Compared with W, C rats showed (I) overweight (+8%, p < 0.05), hyperglycemia (+11%, p < 0.05), hypertriglyceridemia (2-fold, p < 0.001), higher AIP (2-fold, p < 0.01), and lower Q10 level (-55%, p < 0.05); (II) increased LV diastolic diameter (+9%, p < 0.05) and volume (systolic +24%, p < 0.05), posterior wall thinning (-8%, p < 0.05), and larger cardiac output (+24%, p < 0.05); (III) glomerulosclerosis (+21%, p < 0.05), histopathology (+13%, p < 0.05), higher tubular expression of IL-6 (7-fold, p < 0.001), and TNFα (4-fold, p < 0.001). (IV) Correlations were found for LV dimensions with IL-6 (74%, p < 0.001) and TNFα (52%, p < 0.001) and fully abolished after TG and Q10 control. Chronic cola drinking induced cardiac remodeling associated with increase in proinflammatory cytokines and renal damage. Hypertriglyceridemia and oxidative stress were key factors. Hypertriglyceridemic lipotoxicity in the context of defective antioxidant/anti-inflammatory protection due to low Q10 level might play a key role in cardiorenal disorder induced by chronic cola drinking in rats.
Assuntos
Bebidas/efeitos adversos , Glicemia/efeitos dos fármacos , Cola/química , Síndrome Metabólica/sangue , Síndrome Metabólica/induzido quimicamente , Animais , Pressão Sanguínea/efeitos dos fármacos , Colesterol/sangue , Creatinina/sangue , Ecocardiografia , Imuno-Histoquímica , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Síndrome Metabólica/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Triglicerídeos/sangue , Ureia/sangueRESUMO
AIM: We report the effects of long-term cola beverage drinking on glucose homeostasis, endocrine pancreas function and morphology in rats. METHODS: Wistar rats drank: water (group W), regular cola beverage (group C, sucrose sweetened) or "light" cola beverage (group L, artificially sweetened). After 6 months, 50% of the animals in each group were euthanized and the remaining animals consumed water for the next 6 months when euthanasia was performed. Biochemical assays, insulinemia determination, estimation of insulin resistance (HOMA-IR), morphometry and immunohistochemistry evaluations were performed in pancreas. RESULTS: Hyperglycemia (16%, p<0.05), CoQ10 (coenzyme-Q10) decrease (-52%,p<0.01), strong hypertriglyceridemia (2.8-fold, p<0.01), hyperinsulinemia (2.4 fold, p<0.005) and HOMA-IR increase (2.7 fold, p<0.01) were observed in C. Group C showed a decrease in number of α cells (-42%, p<0.01) and ß cells (-58%, p<0.001) and a moderate increase in α cells' size after wash-out (+14%, p<0.001). Group L showed reduction in ß cells' size (-9%, p<0.001) and only after wash-out (L12) a 19% increase in size (p<0.0001) with 35% decrease in number of α cells (p<0.01). Groups C and L showed increase in α/ß-cell ratio which was irreversible only in C (α/ß = +38% in C6,+30% in C12, p<0.001vs.W6). Regular cola induced a striking increase in the cytoplasmic expression of Trx1 (Thioredoxin-1) (2.25-fold in C6 vs. W6; 2.7-fold in C12 vs. W12, p<0.0001) and Prx2 (Peroxiredoxin-2) (3-fold in C6 vs. W6; 2-fold in C12 vs. W12, p<0.0001). Light cola induced increase in Trx1 (3-fold) and Prx2 (2-fold) after wash-out (p<0.0001, L12 vs. W12). CONCLUSION: Glucotoxicity may contribute to the loss of ß cell function with depletion of insulin content. Oxidative stress, suggested by increased expression of thioredoxins and low circulating levels of CoQ10, may follow sustained hyperglycemia. A likely similar panorama may result from the effects of artificially sweetened cola though via other downstream routes.
Assuntos
Bebidas Gaseificadas/efeitos adversos , Cola/química , Ilhotas Pancreáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Análise de Variância , Animais , Glicemia/metabolismo , Bebidas Gaseificadas/análise , Imuno-Histoquímica , Resistência à Insulina/fisiologia , Ilhotas Pancreáticas/patologia , Ratos , Triglicerídeos/sangue , Ubiquinona/análogos & derivados , Ubiquinona/metabolismoRESUMO
A low pH and a high titratable acidity of juices and cola-based beverages are relevant factors that contribute to dental erosion, but the relative importance of these properties to maintain salivary pH at demineralizing levels for long periods of time after drinking is unknown. In this crossover study conducted in vivo, orange juice, a cola-based soft drink, and a 10% sucrose solution (negative control) were tested. These drinks differ in terms of their pH (3.5 ± 0.04, 2.5 ± 0.05, and 5.9 ± 0.1, respectively) and titratable acidity (3.17 ± 0.06, 0.57 ± 0.04 and < 0.005 mmols OH- to reach pH 5.5, respectively). Eight volunteers with a normal salivary flow rate and buffering capacity kept 15 mL of each beverage in their mouth for 10 s, expectorated it, and their saliva was collected after 15, 30, 45, 60, 90, and 120 s. The salivary pH, determined using a mini pH electrode, returned to the baseline value at 30 s after expectoration of the cola-based soft drink, but only at 90 s after expectoration of the orange juice. The salivary pH increased to greater than 5.5 at 15 s after expectoration of the cola drink and at 30 s after expectoration of the orange juice. These findings suggest that the titratable acidity of a beverage influences salivary pH values after drinking acidic beverages more than the beverage pH.
Assuntos
Bebidas , Citrus sinensis/química , Saliva/química , Soluções Tampão , Bebidas Gaseificadas , Ácido Cítrico/química , Cola/química , Estudos Cross-Over , Humanos , Concentração de Íons de Hidrogênio , Valores de Referência , Fatores de Tempo , Titulometria , Erosão Dentária/induzido quimicamenteRESUMO
A low pH and a high titratable acidity of juices and cola-based beverages are relevant factors that contribute to dental erosion, but the relative importance of these properties to maintain salivary pH at demineralizing levels for long periods of time after drinking is unknown. In this crossover study conductedin vivo, orange juice, a cola-based soft drink, and a 10% sucrose solution (negative control) were tested. These drinks differ in terms of their pH (3.5 ± 0.04, 2.5 ± 0.05, and 5.9 ± 0.1, respectively) and titratable acidity (3.17 ± 0.06, 0.57 ± 0.04 and < 0.005 mmols OH- to reach pH 5.5, respectively). Eight volunteers with a normal salivary flow rate and buffering capacity kept 15 mL of each beverage in their mouth for 10 s, expectorated it, and their saliva was collected after 15, 30, 45, 60, 90, and 120 s. The salivary pH, determined using a mini pH electrode, returned to the baseline value at 30 s after expectoration of the cola-based soft drink, but only at 90 s after expectoration of the orange juice. The salivary pH increased to greater than 5.5 at 15 s after expectoration of the cola drink and at 30 s after expectoration of the orange juice. These findings suggest that the titratable acidity of a beverage influences salivary pH values after drinking acidic beverages more than the beverage pH.
Assuntos
Humanos , Bebidas , Citrus sinensis/química , Saliva/química , Soluções Tampão , Bebidas Gaseificadas , Estudos Cross-Over , Ácido Cítrico/química , Cola/química , Concentração de Íons de Hidrogênio , Valores de Referência , Fatores de Tempo , Titulometria , Erosão Dentária/induzido quimicamenteRESUMO
There is no consensus about the waiting time necessary for the patient to start consuming beverages containing colorants again after bleaching. Objective: To evaluate the influence of beverages with coloring agents on bleached bovine incisors considering the time elapsed after bleaching. Materials and methods: Sixty bovine incisors were bleached with 35% hydrogen peroxide for in-office use (Whiteness HP Max) and divided into 10 groups. The color was evaluated with a spectrophotometer (Spectro Shade MICRO) before and after bleaching, employing the CIE-Lab system. After bleaching, the teeth were exposed for 5 min to coffee or cola-based soft drink (CBSD) at different periods after bleaching: 10 min, 1 h, 24 h, 48 h, and 72 h. Color (∆E) and lightness (∆L) variations were obtained from the CIE-Lab coordinates. Data were subjected to two-way ANOVA and Tukey HSD tests (p<0.05). Results: Significant differences were observed between groups for both the ∆L and ∆E values (p<0.001). All specimens presented a decrease in brightness (negative ∆L). The highest ∆E values were observed for teeth stained with a CBSD at 10 min and 1 h (4.12 and 4.16, respectively). Teeth pigmented with coffee presented ∆E values below 3.3 units for all evaluation times. Conclusion: The exposure to coffee after bleaching causes less color changes than the exposure to a CBSD regardless of the time after bleaching. .
Assuntos
Animais , Bovinos , Bebidas Gaseificadas , Café/química , Cola/química , Pigmentação/efeitos dos fármacos , Clareamento Dental/métodos , Dente/efeitos dos fármacos , Análise de Variância , Cor , Peróxido de Hidrogênio/química , Valores de Referência , Espectrofotometria , Propriedades de Superfície/efeitos dos fármacos , Fatores de Tempo , Clareadores Dentários/química , Descoloração de DenteRESUMO
UNLABELLED: There is no consensus about the waiting time necessary for the patient to start consuming beverages containing colorants again after bleaching. OBJECTIVE: To evaluate the influence of beverages with coloring agents on bleached bovine incisors considering the time elapsed after bleaching. MATERIALS AND METHODS: Sixty bovine incisors were bleached with 35% hydrogen peroxide for in-office use (Whiteness HP Max) and divided into 10 groups. The color was evaluated with a spectrophotometer (Spectro Shade MICRO) before and after bleaching, employing the CIE-Lab system. After bleaching, the teeth were exposed for 5 min to coffee or cola-based soft drink (CBSD) at different periods after bleaching: 10 min, 1 h, 24 h, 48 h, and 72 h. Color (∆E) and lightness (∆L) variations were obtained from the CIE-Lab coordinates. Data were subjected to two-way ANOVA and Tukey HSD tests (p<0.05). RESULTS: Significant differences were observed between groups for both the ∆L and ∆E values (p<0.001). All specimens presented a decrease in brightness (negative ∆L). The highest ∆E values were observed for teeth stained with a CBSD at 10 min and 1 h (4.12 and 4.16, respectively). Teeth pigmented with coffee presented ∆E values below 3.3 units for all evaluation times. CONCLUSION: The exposure to coffee after bleaching causes less color changes than the exposure to a CBSD regardless of the time after bleaching.
Assuntos
Bebidas Gaseificadas , Café/química , Cola/química , Pigmentação/efeitos dos fármacos , Clareamento Dental/métodos , Dente/efeitos dos fármacos , Análise de Variância , Animais , Bovinos , Cor , Peróxido de Hidrogênio/química , Valores de Referência , Espectrofotometria , Propriedades de Superfície/efeitos dos fármacos , Fatores de Tempo , Clareadores Dentários/química , Descoloração de DenteRESUMO
BACKGROUND: Atherosclerosis is a major health burden. Metabolic disorders had been associated with large consumption of soft drinks. The rising incidence of atherosclerosis and metabolic alterations warrants the study of long-term soft drink consumption' effects on metabolism and atherosclerosis in genetic deficiency of apolipoprotein E which typically develops spontaneous atherosclerosis and metabolic alterations. METHODS: ApoE-/- mice were randomized in 3 groups accordingly with free access to: water (W), regular cola (C) or light cola (L). After 8 weeks, 50% of the animals in each group were euthanized ( TREATMENT: W8, C8, L8). The remaining mice (all groups) drank water for 8 weeks and were euthanized (Washout: W16, C16, L16). Body weight and food and drink consumption were periodically measured. Blood was collected (biochemistry). At autopsy, transverse aortic sinus sections were serially cut and stained (histomorphometry); livers and kidneys were processed (microscopy). MANOVA (identification of variance factors) was followed by ANOVA and LSD tests (within-factor differences between levels). Conventionally a p< 0.05 was considered significant. RESULTS: TREATMENT increased drinking volumes (vs W8: 4 fold C8, p<0.0001; +47% L8, p<0.02). Only C reduced eating amounts (-54%, p<0.05 vs W8). I). Compared with W8: C8 developed hyperglycemia (+43%, p<0.03) and increased non-HDL cholesterol (+54%, p<0.05); L8 showed decreased glycemia (-15%, p<0.05 vs W8) and increased creatinine (2.5 fold, p<0.04), urea (+74, p<0.03) and aspartate-aminotransferase (2.8 fold, p<0.05). Hypercreatininemia was observed in L16 (2.7 fold vs W16, p<0.05). Hypertriglyceridemia (+91%, p<0.008) and hyperuremia (+68%, p<0.03) developed over time of study (age). II). TREATMENT caused plaque area increase (vs W8: 28% C8, p<0.02 and 50% L8, p<0.01; vs W16: 43% C16, p<0.05 and 68% L16, p<0.02) and stenosis (vs W8: 38% C8, p<0.04 and 57% L8, p<0.01; vs W16: 71% C16, p<0.01 and 46% L16, p<0.04). Age also caused plaque area increase (56%, p<0.04). TREATMENT- and age-effects on plaque enlargement were additive. CONCLUSION: Cola beverages caused atherosclerotic lesions' enlargement with metabolic (C) or non metabolic disturbances (L). ApoE-/- mice were particularly sensitive to L treatment. These findings may likely relate to caramel colorant and non-nutritive sweeteners in cola drinks and have potential implications in particularly sensitive individuals.
Assuntos
Apolipoproteínas E/deficiência , Bebidas/efeitos adversos , Cola , Ingestão de Líquidos/fisiologia , Doenças Metabólicas/induzido quimicamente , Placa Aterosclerótica/induzido quimicamente , Animais , Apolipoproteínas E/genética , Feminino , Masculino , Doenças Metabólicas/metabolismo , Doenças Metabólicas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Distribuição AleatóriaRESUMO
OBJECTIVE: To evaluate whether the type of cola drink (regular or diet) could influence the wear of enamel subjected to erosion followed by brushing abrasion. METHOD AND MATERIALS: Ten volunteers wore intraoral devices that each had eight bovine enamel blocks divided into four groups: ER, erosion with regular cola; EAR, erosion with regular cola plus abrasion; EL, erosion with light cola; and EAL, erosion with light cola plus abrasion. Each day for 1 week, half of each device was immersed in regular cola for 5 minutes. Then, two blocks were brushed using a fluoridated toothpaste and electric toothbrush for 30 seconds four times daily. Immediately after, the other half of the device was subjected to the same procedure using a light cola. The pH, calcium, phosphorus, and fluoride concentrations of the colas were analyzed using standard procedures. Enamel alterations were measured by profilometry. Data were tested using two-way ANOVA and Bonferroni test (P<.05). RESULTS: Regarding chemical characteristics, light cola presented pH 3.0, 13.7 mg Ca/L, 15.5 mg P/L, and 0.31 mg F/L, while regular cola had pH 2.6, 32.1 mg Ca/L, 18.1 mg P/L, and 0.26 mg F/L. The light cola promoted less enamel loss (EL, 0.36 Μm; EAL, 0.39 Μm) than its regular counterpart (ER, 0.72 Μm; EAR, 0.95 Μm) for both conditions. There was not a significant difference (P>.05) between erosion and erosion plus abrasion for light cola. However, for regular cola, erosion plus abrasion resulted in higher enamel loss than erosion alone. CONCLUSION: The data suggest that light cola promoted less enamel wear even when erosion was followed by brushing abrasion.
Assuntos
Bebidas Gaseificadas/efeitos adversos , Abrasão Dentária/etiologia , Erosão Dentária/etiologia , Escovação Dentária/efeitos adversos , Adulto , Análise de Variância , Animais , Bovinos , Cola , Esmalte Dentário/efeitos dos fármacos , Sacarose Alimentar , Humanos , Concentração de Íons de Hidrogênio , Estatísticas não Paramétricas , Edulcorantes , Adulto JovemRESUMO
The obi (Cola acuminate) is a native fruit from Africa, which has been mainly used in the production of soft drinks and also in rituals of African religions. In this paper, the mineral composition of obi collected in seven different cities from Bahia State, Brazil was determined and evaluated using multivariate analysis. The samples were digested using nitric acid and hydrogen peroxide and were analyzed using inductively coupled plasma optical emission spectrometry. The accuracy of the method was confirmed by analysis of a certified reference material of apple leaves, furnished by National Institute of Standard and Technology. The study involved 46 samples, being 18 of the red specie and 28 for the white specie. The results expressed as milligrams of element per 100 g(-1) of sample demonstrated that the concentration ranges varied of 21.28-548.77 for potassium, 15.73-129.85 for phosphorous, 27.95-286.92 for calcium, 7.67-134.45 for magnesium, 0.05-1.41 for manganese, 0.21-0.94 for iron, 0.11-0.39 for copper, 0.27-1.35 for zinc, and 0.025-0.517 for strontium. The principal component analysis and hierarchical cluster analysis evidenced that the mineral composition of the red specie is different of the white specie. The red obi has mineral content higher than white obi.
Assuntos
Cola/química , Minerais/análise , Cálcio/análise , Cobre/análise , Magnésio/análise , Manganês/análise , Fósforo/análise , Potássio/análise , Zinco/análiseRESUMO
This in vitro study aimed to analyze the effects of application of xylitol varnishes and solutions to protect against enamel erosion. Twelve bovine enamel specimens were pre-treated with 5% NaF-Duraphat varnish, 10% xylitol varnish, 20% xylitol varnish, placebo varnish, 5% NaF solution, 10% xylitol solution or 20% xylitol solution. The varnishes and solutions were applied for 6 h and 1 min, respectively. Controls remained untreated (n = 12). Specimens were then subjected to erosive demineralization (Coca-Cola, 4 × 90 s/d) and remineralization (artificial saliva, 2 h) cycling for 10 days. After 5 days, the varnishes and solutions were reapplied. After reapplication, two specimens per group were analyzed by SEM. Enamel loss was measured profilometrically after the 5th and 10th days. Data were then analyzed statistically by ANOVA and Tukey's post-hoc test (n = 10, P < 0.05). After the 5th day, all varnishes and 20% xylitol solution significantly reduced the enamel loss when compared to the placebo varnish/control. After 10 days of erosive pH cycling, both xylitol varnishes and solutions significantly reduced the enamel erosion when compared with the control. However, 10% xylitol solution produced a smooth layer on eroded enamel and significantly reduced the enamel erosion when compared to the placebo varnish/control. Xylitol thus appears to be a good option to partially reduce enamel erosion.
Assuntos
Erosão Dentária/prevenção & controle , Xilitol/uso terapêutico , Análise de Variância , Animais , Bebidas Gaseificadas/efeitos adversos , Bovinos , Cola/efeitos adversos , Esmalte Dentário/patologia , Fluoretos Tópicos/uso terapêutico , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Pintura , Fluoreto de Sódio/uso terapêutico , Estatísticas não Paramétricas , Erosão Dentária/etiologia , Xilitol/administração & dosagemRESUMO
A presente pesquisa teve como objetivo analisar as seguintes gramaturas de cola: 270; 330; 364 e 390 g.m-² a partir da produção de compensados fenólicos utilizando duas espécies florestais; Copaifera duckei e Eperua oleifera e avaliar a flexão estática dos painéis. A madeira foi proveniente da área de manejo florestal sustentado da Indústria de Madeira Compensada localizada em Manicoré, município do Amazonas. As lâminas foram produzidas na Gethal Amazonas S.A - Indústria de Madeira Compensada em Itacoatiara - AM com espessura de 2,2 mm. Foram produzidas a nível industrial 40 painéis, 20 por espécie no total de 8 tratamentos. O experimento foi completamente casualizado com arranjo fatorial. Foi utilizado a norma Européia EN 310: 1993. Os valores de densidade básica da espécie Copaifera duckei foi de 0,60 (g.cm-²) e 0,62 (g.cm-²) para Eperua oleifera. No ensaio de flexão estática, sentido paralelo à grã, somente a espécie Copaifera duckei apresentou diferença significativa a 5 por cento pelo Teste de Dunnette para as propriedades de MOE e MOR. No sentido perpendicular a grã, as espécies Copaifera duckei e Eperua oleifera tanto o MOE quanto o MOR apresentaram diferenças significativas a 5 por cento de probabilidade.
The objective of the present research was to analyze 270; 330; 364 and 390 g.m-² amounts of glue in the production of fenolic plywood, using two forest species; Copaifera duckei and Eperua oleifera, and evaluate the static bending of the panels. The wood came from an area of sustained forest pertaining to the Plywood Industry located in Manicoré, county of Amazonas. The panels were produced with thicknesses of 2.2mm at the Gethal Amazonas S.A in Itacoatiara - AM. Forty panels, 20 per species, were produced an industrial level, using a total of 8 treatments. The experiment was completely randomized with factorial arrangement. The European standard EN 310: 1993 was used. The basic density values were 0.60 (g.cm-²) for Copaifera duckei, and 0.62 (g.cm-²) for Eperua oleifera. In static bending, parallel to the grain, only Copaifera duckei presented a significant difference at 5 percent in the Dunnette Test for the properties of MOE and MOR. In the perpendicular sense to the grain, Copaifera duckei and Eperua oleifera presented significant differences, for MOE as much as MOR, at 5 percent of probability.
Assuntos
Agricultura Florestal , Cola , FabaceaeRESUMO
La Fitoexperimentación pura es un mecanismo adecuado para conocer el efecto biológico que tiene uma substancia sobre una planta, la importancia de esto es que conociendo los síntomas que genera la sustancia en dosis cuantificable es posible la aplicación de esa sustancia para corregir los síntomas causados por la misma.
Assuntos
Agricultura , Agricultura , Cola , Ensaio Clínico , Fertilizantes , Homeopatia , Bebidas Gaseificadas , Triticum , PlantasRESUMO
La Fitoexperimentación pura es un mecanismo adecuado para conocer el efecto biológico que tiene uma substancia sobre una planta, la importancia de esto es que conociendo los síntomas que genera la sustancia en dosis cuantificable es posible la aplicación de esa sustancia para corregir los síntomas causados por la misma.
Assuntos
Agricultura , Agricultura , Fertilizantes , Triticum , Ensaio Clínico , Bebidas Gaseificadas , Cola , Homeopatia , PlantasRESUMO
No presente trabalho faz-se o primeiro registro das metacercárias do digenético Clinostomum marginatum (Clinostomidae) parasitando espécimes do peixe ornamental Pterophyllum scalare, provenientes do estado do Rio de Janeiro, Brasil. Os parasitos foram encontrados encistados nas nadadeiras, formandopequenos nódulos amarelos
Assuntos
Animais , Peixes , Trematódeos , Brasil , Cola , Brânquias , Interações Hospedeiro-Parasita , TrematódeosRESUMO
Se presenta el caso de un mortinato que presentó bandas amnióticas constrictivas y adhesiones placentarias, así como el complejo pared-cuerpo-extremidad y la presencia de seudocola. El caso fue estudiado en la Unidad de Patología del Hospital General de Acapulco. Esta entidad denominada cyllosomus y pleurosomus por la teratología antigua, es una rareza. Las anomalías se interpretaron como defectos relacionados con las bandas o con defectos de comprensión. Estos últimos incluyen alteraciones en los miembros, deficiencias en la pared del cuerpo, defectos en el tubo neural y acortamiento del cordón umbilical. La escasez de comunicados en la literatura de nuestro medio es debida a la negligencia respecto de comunicar casos como el que aquí comentamos, lo cual depende también del interés local en la teratología