Universidade Estadual de Londrina

About: Universidade Estadual de Londrina is a education organization based out in Londrina, Brazil. It is known for research contribution in the topics: Population & Context (language use). The organization has 13052 authors who have published 19291 publications receiving 212123 citations.

Uremic hyperhomocysteinemia: A randomized trial of folate treatment for the prevention of cardiovascular events

Abstract: Homocysteine is a risk factor for atherosclerosis in the general population, and serum homocysteine levels are almost universally elevated in chronic renal failure patients. When such patients are treated with dialysis, cardiovascular disease accounts for more than 50% of their mortality, which, in some proportion, may be pathophysiologically related to the elevated serum homocysteine levels. From April 2003 to March 2005, we conducted a 2-year, double-blind, randomized, placebo-controlled trial of 186 patients with end-stage kidney disease due to any cause, who were older than 18 years and stable on hemodialysis. Patients were assigned to receive either oral folic acid 10 mg 3 times a week immediately after every dialysis session under nurse supervision or an identical-appearing placebo for the entire study. On admission, plasma total homocysteine (tHcy) levels were above 13.9 micromol/L in 96.7% of patients (median 25.0 micromol/L, range 9.3-104.0 micromol/L). In the placebo group, tHcy levels remained elevated at 6, 12, and 24 months, while oral folate significantly decreased tHcy to a median value of 10.5 (2.8-20.3) micromol/L, (p<0.01). During the study, 38 patients (folic acid group 17 vs. placebo group 21; p=0.47) died from cardiovascular disease. Kaplan-Meier life table analysis dealing with the incidence of cardiovascular events, both fatal and nonfatal (myocardial infarction, arrhythmias, angina, heart failure, cerebrovascular accident), showed that 2 years of folic acid treatment and the lowering of the homocysteine blood levels had no effect on cardiovascular events (p=0.41; hazard ratio 1.24, 95% CI 0.74-2.10). However, the carotid artery intima-media wall thickness measured in a blinded fashion decreased from 1.94 +/- 0.59 mm to 1.67 +/- 0.38 mm (p<0.01) after 2 years of folate therapy. In this short-term study of uremic patients, 2 years of folic acid supplementation normalized the tHcy blood levels in 92.3% of patients but did not change the incidence of cardiovascular events compared with the control group. However, ultrasonography of the common carotid arteries performed at entry and 24 months later showed a significant decrease in intima-media thickness with folate supplementation. This suggests that early folate supplementation may benefit patients with chronic renal failure by preventing cardiovascular deterioration.

A comparison between visual, intraoral scanner, and spectrophotometer shade matching: A clinical study.

Abstract: Statement of problem Visual shade matching is subjective and a cause of concern for clinicians. Different measurement devices have been developed to assist in tooth color selection and to achieve better esthetic results. However, consensus is lacking as to which method of tooth shade selection provides more predictable results. Purpose The purpose of this clinical study was to compare the reliability of different visual and instrumental methods for dental shade matching. Material and methods Visual shade matching was performed by 3 experienced clinicians using 2 different shade guides (VITA Classical A1-D4 and VITA Toothguide 3D-MASTER with 29 tabs; VITA Zahnfabrik) with and without the aid of a light-correcting device (Smile Lite; Smile Line). An intraoral scanner (TRIOS; 3Shape A/S) and a spectrophotometer (VITA Easyshade Advance 4.0; VITA Zahnfabrik) were also used for color shade matching. The instrumental methods were repeated 3 times to determine repeatability. Shade-matching sessions for each method were performed under controlled lighting on the middle third of the maxillary right central incisor of 28 participants. The Fleiss' kappa statistical test was used to assess the reliability of each method. The weighted kappa statistical test was used to assess the agreement between the shades matched by different methods (α=.05). Results Instrumental methods were more accurate than visual methods. The best performance was found for the intraoral scanner configured for the 3D-MASTER scale (Fleiss' kappa value of .874) and for the spectrophotometer configured for the VITA Classical scale (Fleiss' kappa value of .805). The best visual shade-matching method was the VITA Classical scale associated with the light-correcting device (Fleiss' kappa value of .322). The Classical scale without the light-correcting device showed the poorest reliability (Fleiss' kappa value of .177) (P Conclusions Instrumental methods for color shade matching were more reliable than the visual methods tested.

Bird species sensitivity in a fragmented landscape of the atlantic forest in Southern Brazil

Abstract: I tested whether terrestrial/understory habits, large body sizes, low tolerance to edge or to matrix habitat, and food/habitat specialization are characteristics of the most vulnerable bird species based on point counts conducted in 14 forest fragments in northern Paransouthern region of the Brazilian Atlantic forest. In addition, the sensitivity level of each bird species to forest fragmentation in northern Paran´ (high, medium, and low) was compared to the Vicosa region, another fragmented landscape of the Atlantic forest. Contrary to expectations, large body size and terrestrial/understory habits were not features clearly related to high sensitivity to forest fragmentation; but species with tolerance to edge did have lower sensitivity. I found also that specialized habitat/food were not good predictors of extinctions; the most specialized guilds, bamboo and vine-tangle insectivores and trunk and twig insectivores, had a high number of species with low sensitivity. Patterns of sensitivity were compared for 75 bird species that occurred in both northern Parannd Vic higher incongruence occurred for 14 and 7 species considered as highly sensitive in Vicosa but were of medium or low sensitivity, respectively, in northern ParanThese differences may occur because sensitivity to habitat fragmentation may vary from the center to the periphery of a species' geographic range. Geographic variation in patterns of sensitivity to forest fragmentation may be important for conservation planning.