Strength of a Zirconia- Reinforced Glass-Ceramic After Diamond Bur Adjustment.

INTRODUCTION: Adjustments with diamond burs on the ceramic surface can affect its roughness and decrease flexural strength. This study evaluated the effect of polishing or glazing on the surface roughness and biaxial flexural strength of a zirconia-reinforced lithium silicate glass-ceramic upon adjustment with diamond burs. METHODS: Seventy disks were prepared according to ISO 6872 and divided into seven groups (n = 10) according to different adjustments and finishing processes. Surface roughness was measured prior to biaxial flexural strength testing. The topography was analyzed using an atomic force microscope , fracture markings were identified using a stereomicroscope and representative specimens were analyzed using scanning electron microscopy. RESULTS: The use of diamond burs significantly increased the surface roughness and decreased the strength of the evaluated ceramic (p⟨0.05). Polishing reduced the ceramic's roughness but resulted in flexural strength similar to that of the groups with wear (p⟩0.05). The glaze-treated specimens showed flexural strength statistically similar to the control group (p>0.05) but higher roughness, similar to those with wear. CONCLUSIONS: Polishing reduced the surface roughness but did not affect the biaxial flexural strength of the ZLS ceramic. At the same time, the application of glaze after wear increased the strength.

Milk yield, milk composition, and hepatic lipid metabolism in transition dairy cows fed flaxseed or linola.

The response of transition dairy cows to dietary supplementation with fat sources of various fatty acid profiles could affect hepatic fat metabolism differently. Twenty-eight Holstein cows were blocked for similar calving date 4wk before expected parturition to compare the effects of feeding sources of n-3 and n-6 fatty acids on milk production and composition, plasma metabolites, and liver parameters. Cows within each block were assigned to 1 of 3 isonitrogenous and isoenergetic diets: control with a source of calcium salts of palm oil (MEG; 1.1 and 2.6% of the dry matter in prepartum and postpartum diets, respectively); n-3 fatty acids supplied as whole flaxseed (WFL; 4.8 and 7.7% of the dry matter in prepartum and postpartum diets, respectively); and n-6 fatty acids supplied as whole linola (WLO; 4.8 and 7.7% of the dry matter in prepartum and postpartum diets, respectively). Diets were fed until wk 14 of lactation. Contrasts of WFL versus WLO and polyunsaturated fatty acids versus MEG were compared. Cows fed polyunsaturated fatty acids increased dry matter intake over time at a greater extent than those fed MEG, which resulted in enhanced energy balance. Cows fed MEG produced more milk compared with those fed polyunsaturated fatty acids, and there was no difference between those fed WFL and WLO. We found no effect on body condition score and body weight. Plasma concentrations of glucose, fatty acids, and BHB were similar among diets. There was no effect of diet on concentration of glycogen and activities of superoxide dismutase and glutathione peroxidase in the liver. We observed higher concentrations of hepatic lipids and triacylglycerol in cows fed MEG compared with those fed polyunsaturated fatty acids, and no difference between WFL and WLO. Hepatic catalase activity tended to be higher on wk 4 after calving for cows supplemented with WFL compared with those fed WLO. Feeding linoleic and linolenic acids as unprotected oilseeds increased dry matter intake over time at a greater extent for cows fed MEG, improved the energy status, and lowered hepatic lipids and triacylglycerol contents, which may contribute to enhance the health status of transition dairy cows.

Increased concentration of plasma homocysteine in children with systemic lupus erythematosus.

OBJECTIVE: Studies in adults with SLE have evidenced increase of homocysteine related, mainly, to thromboembolic events. The aim of our study was to evaluate plasma homocysteine concentration in children with systemic lupus erythematosus (SLE) and its correlation with renal involvement, serum and erythrocyte folate, vitamin B12, antiphospholipid antibodies, estimated creatinine clearance and dyslipidemia. METHODS: Thirty-two children (29 females) with SLE and 32 healthy controls (29 females) matched for age and sex were included in the study. The mean age of patients and controls was 14.2 years (range from 10 to 18 years). Only one patient presented one thrombotic event. Plasma homocysteine, erythrocyte and serum folate, vitamin B12, lipid profile, antiphospholipid antibodies and estimated creatinine clearance were evaluated. Raised homocysteine concentration was defined as equal or more than 12.9 mol/L. RESULTS: Raised homocysteine concentration was detected in 15 (46.9%) children with SLE with an important statistical difference in relation to control group (p < 0.001). A positive correlation was found between plasma homocysteine concentration and renal involvement (odds ratio 11.1 [95% CI 1.50-82.24], p = 0.01) based on the presence of renal biopsy, abnormalities of urine sediment and/or serum creatinine. However, when we performed the estimated creatinine clearance the correlation with homocysteine concentration was not positive. We did not observe abnormalities in serum and erythrocyte folate and vitamin B12 in our patients. However, they presented significant higher concentrations of TC total cholesterol (p = 0.005) and of LDL low-density lipoprotein (p = 0.02) than controls. CONCLUSION: Elevated plasma homocysteine concentration is frequent in children with SLE. We believe that these results may signalize to the possibility of complications in our patients later in life. Further long-term and prospective studies are needed in order to determine the real role of the homocysteine concentration as a risk factor in children.

[Bilateral abducens nerve palsy in nasopharyngeal carcinoma]. / Paralisia bilateral do abducente em carcinoma de nasofaringe.

We report a case of bilateral abducens palsy as initial finding in nasopharyngeal carcinoma. Possible mode of involvement is discussed. Only one case has been reported in the past.