Luis Guillermo Coca Velarde

Corneal-thickness spatial profile and corneal-volume distribution: Tomographic indices to detect keratoconus

PURPOSE: To evaluate whether the corneal‐thickness spatial profile and corneal‐volume distribution differentiate keratoconic corneas from normal corneas using new tomography parameters. SETTING: Subspecialty cornea and refractive practice, Fluminense Federal University, Rio de Janeiro, Brazil. METHODS: Forty‐six eyes diagnosed with mild to moderate keratoconus and 364 normal eyes were studied by the Pentacam Comprehensive Eye Scanner. Corneal thickness at the thinnest point and the averages of the points on 22 imaginary circles centered on the thinnest point with increased diameters at 0.4 mm steps were calculated to create a corneal‐thickness spatial profile. Corneal volume was calculated within diameters from 1.0 to 7.0 mm with 0.5 mm steps centered on the thinnest point to create the corneal‐volume distribution. The percentage increase in thickness and the percentage increase in volume were calculated for each position of the corneal‐thickness spatial profile and corneal‐volume distribution from their first value. Statistical analysis was done using the Wilcoxon 2‐independent‐sample test to compare mean levels using S‐Plus‐4.0 software (MathSoft) and a normal linear model under a Bayesian frame for estimating the mean variation in thickness and volume using the BUGS 0.6 package. RESULTS: Statistically significant differences were observed between the groups (P<.05) in all positions of corneal‐thickness spatial profile and corneal‐volume distribution and in the percentage increase in thickness and percentage increase in volume between 3.5 mm and 7.0 mm diameters. CONCLUSIONS: Corneal‐thickness spatial profile, corneal‐volume distribution, percentage increase in thickness, and percentage increase in volume were different between keratoconic corneas and normal corneas and could serve as indices to diagnose keratoconus and screen refractive candidates. Further studies are necessary to evaluate whether these tomographic indices are more sensitive and specific than the classic Placido‐based topography.

The effect of autologous concentrated bone-marrow grafting on the healing of femoral shaft non-unions after locked intramedullary nailing

The aim of this study was to assess the union rates in a series of patients with failed femoral shaft aseptic non-union who were treated with percutaneous concentrated autologous bone marrow grafting. Bone marrow harvesting and cell injection were performed under general anaesthesia in a single surgical procedure. Radiographic union was diagnosed in fractures with a score ≥ 10 according to the radiographic union scale in tibial fractures (RUST) and confirmed by clinical examination. Eight out of 16 patients progressed to consolidation (RUST score ≥ 10). Radiographic evidence of fracture union was observed at an average of 4.75 ± 1.75 months (range 3 to 8 months). All eight patients who did not progress to union within 12 months following the cell grafting procedure had a RUST score ≤ 10 (range 4 to 9). There were no differences in age, number of previous surgeries, duration of nonunion and preoperative RUST score between the patients that developed solid union and those with failed consolidation. However, a relationship between the number of osteoprogenitors injected and the rate of union was noted, 20.2 ± 8.6 × 10(8) versus 9.8 ± 4.3 × 10(8), p<0.005, between the patients with and without union, respectively. The efficacy of percutaneous autologous concentrated bone marrow grafting seems to be related to the number of osteoprogenitors available in the aspirates. Optimisation of the aspiration technique and concentration process is of paramount importance to increase the incidence of a successful outcome.

Alpha-tocopherol supplementation decreases electronegative low-density lipoprotein concentration [LDL(−)] in haemodialysis patients

BACKGROUND Oxidative stress is a significant contributor to cardiovascular diseases (CVD) in haemodialysis (HD) patients, predisposing to the generation of oxidized low-density lipoprotein (oxLDL) or electronegatively charged LDL subfraction. Antioxidant therapy such as alpha-tocopherol acts as a scavenger of lipid peroxyl radicals attenuating the oxidative stress, which decreases the formation of oxLDL. The present study was designed to investigate the influence of the alpha-tocopherol supplementation on the concentration of electronegative low-density lipoprotein [LDL(-)], a minimally oxidized LDL, which we have previously described to be high in HD patients. METHODS Blood samples were collected before and after 120 days of supplementation by alpha-tocopherol (400 UI/day) in 19 stable HD patients (50 +/- 7.8 years; 9 males). The concentrations of LDL(-) in blood plasma [using an anti-LDL- human monoclonal antibody (mAb)] and the anti-LDL(-) IgG auto-antibodies were determined by ELISA. Calculation of body mass index (BMI) and measurements of waist circumference (WC), triceps skin folds (TSF) and arm muscle area (AMA) were performed. RESULTS The plasma alpha-tocopherol levels increased from 7.9 microM (0.32-18.4) to 14.2 microM (1.22-23.8) after the supplementation (P = 0.02). The mean concentration of LDL(-) was reduced from 570.9 microg/mL (225.6-1241.0) to 169.1 microg/mL (63.6-621.1) (P < 0.001). The anti-LDL(-) IgG auto-antibodies did not change significantly after the supplementation. The alpha-tocopherol supplementation also reduced the total cholesterol and LDL-C levels in these patients, from 176 +/- 42.3 mg/dL to 120 +/- 35.7 mg/dL (P < 0.05) and 115.5 +/- 21.4 mg/dL to 98.5 +/- 23.01 mg/dL (P < 0.001), respectively. CONCLUSION The oral administration of alpha-tocopherol in HD patients resulted in a significant decrease in the LDL(-), total cholesterol and LDL-C levels. This effect may favour a reduction in cardiovascular risk in these patients, but a larger study is required to confirm an effect in this clinical setting.

Is a body mass index of 23 kg/m2 a reliable marker of protein–energy wasting in hemodialysis patients?

OBJECTIVE To evaluate the body composition and inflammatory status in patients on hemodialysis (HD) according to the cutoff of 23 kg/m² for the body mass index (BMI). METHODS Forty-seven patients (30 men, 11 diabetics, 53.8 ± 12.2 y of age, 58.2 ± 50.9 mo on HD) were studied. Anthropometric data and handgrip strength were evaluated. C-reactive protein, tumor necrosis factor-α, leptin, and interleukin-6 were measured. Mortality was assessed after 24 mo of follow-up. RESULTS Nineteen patients (40.4%) presented BMI values lower than 23 kg/m² and leptin levels, midarm muscle area, and free-fat mass were significantly lower in these patients. The prevalence of functional muscle loss according to handgrip strength was not different between the BMI groups. The sum of skinfold thicknesses, the percentage of body fat, fat mass, the fat mass/free-fat mass ratio, and waist circumference were significantly lower in patients with a BMI lower than 23 kg/m², but the mean values did not indicate energy wasting. Patients with a BMI higher than 23 kg/m² presented a higher prevalence of inflammation and higher waist circumference and body fat values. The adiposity parameters were correlated with C-reactive protein and leptin. A Cox multivariate regression analysis demonstrated that C-reactive protein, tumor necrosis factor-α, and interleukin-6 predict cardiovascular mortality. CONCLUSION Patients on HD with a BMI lower than 23 kg/m² did not present signs of energy wasting, whereas those with a BMI higher than 23 kg/m² had more inflammation, probably because of a greater adiposity. Thus, the BMI value of 23 kg/m² does not seem to be a reliable marker of protein-energy wasting in patients on HD.

Prevalence of Metabolic Syndrome in Elderly and Agreement among Four Diagnostic Criteria

Background Metabolic syndrome (MS) is an aggregation of risk factors that increase the incidence of cardiovascular events and diabetes mellitus (DM). Population aging is accompanied by higher prevalence of MS, which varies depending on the population studied and the diagnostic criteria used. Objective To determine prevalence of MS in the elderly using four diagnostic criteria and agreement between them. Methods Cross-sectional study on 243 patients older than 60 years (180 women) in Niterói, RJ. They were evaluated by clinical examination, fasting glucose, fasting insulin, lipid profile and anthropometric measurements - weight, height, waist circumference and waist/hip ratio. Prevalence of MS was estimated by World Health Organization (WHO) modified, National Cholesterol Education Program - Adult Treatment Panel III (NCEP-ATP III), International Diabetes Federation (IDF) and Joint Interim Statement (JIS) criteria. Results Prevalence was high with the four criteria WHO (51.9%), NCEP-ATPIII (45.2%), IDF (64.1%) and JIS (69.1%), and agreement between criteria by kappa was moderate in almost all comparisons WHO vs. IDF (k = 0.47;95% confidence interval (CI), 0.35 to 0.58); WHO vs. NCEP-ATPIII (k = 0.51; 95% CI, 0.40 to 0.61); WHO vs. JIS (k = 0.45; 95% CI, 0.33 to 0.56); IDF vs. NCEP-ATPIII (k = 0.55; 95% CI, 0.45 to 0.65) and NCEP-ATPIII vs. JIS (k = 0.53; 95% CI, 0.43-0.64), except between IDF vs. JIS (K = 0.89;95% CI, 0.83 to 0.95), which was considered good. Conclusion Prevalence of MS was high with the four diagnostic criteria, mainly by JIS. There was good agreement between JIS and IDF criteria and moderate among the others.

Impact of flaxseed intake upon metabolic syndrome indicators in female Wistar rats

PURPOSE To evaluate whether the prolonged consumption of flaxseed minimize the factors that trigger MS in healthy rats. METHODS Pregnant rats were divided immediately after delivery into two groups during the lactation period, a control group (CG) receiving casein-based diet with 17% of protein, and a Flaxseed group (FG) with casein-based diet plus 25% of flaxseed. At weaning, 12 offspring of each group continued to receive the same feed but with 10% of protein up to 200 days old. RESULTS FG showed a significant reduction in body weight (p=0.001), total cholesterol levels (p<0.0001), triglycerides (p=0.0001), and glucose (p=0.001). CONCLUSION The flaxseed alters the indicators related to development of metabolic syndrome, because it has beneficial effects on lipids and glucose profiles and prevents the excess of body weight gain.

Changes in Ophthalmic Artery Doppler Indices in Hypertensive Disorders During Pregnancy

To compare the ophthalmic artery Doppler indices observed in women with singleton pregnancies complicated by hypertension and to correlate the indices observed in hypertensive pregnant women with those observed in healthy pregnant women.

Association between Vitamin A deficiency and socioeconomic, nutritional and obstetric variables

This study verified the night blindness prevalence, the first manifestation of this deficiency, and its association with socioeconomic, nutritionals and obstetric variables of 92 pregnant who were assisted on a health municipal center in Diamantina, Vale do Jequitinhonha. Data was collected through a model interview recommended by WHO (1996) to diagnose night blindness. The statistic analysis used Fisher exact test and Wilcoxon test. The results showed a higher prevalence of night blindness at Diamantina districts and neighbor cities (13.04%). No significant association was found between night blindness and socioeconomic and obstetric variables (p>0.05). It was observed a low vitamin A levels by pregnant with night blindness (4.4). This found shows the necessity of more investigations on vitamin A deficiency in order to help prevent, diagnose and combat this issue.

Seroepidemiological study of human parvovirus B19 among human immunodeficiency virus-infected patients in a medium-sized city in Rio de Janeiro, Brazil

Parvovirus B19 (B-19) may cause chronic anaemia in immunosuppressed patients, including those infected with human immunodeficiency virus (HIV). We studied single serum samples from 261 consecutive HIV-infected patients using an enzyme immunoassay to detect IgG antibodies to B-19. The seroprevalence of B-19-IgG was 62.8%. The differences in seroprevalence across gender, age, educational categories, year of collection of the serum samples, clinical and antiretroviral therapy characteristics, CD4+ count, CD4+ and CD8+ percentage and CD4+/CD8+ ratios were neither substantial nor statistically significant. There was a non-significant, inverse association between B-19 seropositivity and plasma HIV load and haemoglobin level. Our results indicated that 37.1% of patients might be susceptible to B-19 infection and remained at risk for being infected, mainly during epidemic periods. As B-19 infection can be treated with immune globulin preparations, it may be included in the diagnostic approach toward chronic anaemia in HIV-infected patients.

Neonatal outcome in women with preterm premature rupture of membranes (PPROM) between 18 and 26 weeks

Abstract Objective: The aim of this study was to identify adverse neonatal outcomes and identifies the predictors of adverse neonatal outcomes in premature rupture of membranes before 26 weeks. Methods: Data were collected between January 2005 and December 2011 from all pregnant women who presented preterm premature rupture of membranes (PPROM) between 18 and 26 complete weeks of gestation and were admitted to one of three Brazilian institutes. The adverse outcomes included mortality or the development of a severe morbidity during the length of stay in the neonatal intensive care unit (NICU). The descriptive statistics of the population were reported. A multiple logistic regression was performed for each predictor of neonatal adverse outcomes. The area under the receiver operating characteristics curves for the birth weight was calculated. Results: Composite adverse outcomes during the NICU stay occurred in 82.1% (n = 23) of the cases and included 33 (54%) neonatal deaths, 19 (67.8%) cases of retinopathy of prematurity (ROP), 13 (46.4%) cases of pulmonary hypoplasia (BPD), 8 (28.5%) cases of periventricular-intraventricular hemorrhage (PIH) and 3 (10.7%) cases of periventricular leukomalacia (PVL). Only 17.8% (n = 5) of the neonates survived without morbidity. The area under the curve for the birth weight was 0.90 (95% IC: 0.81–0.98) for the prediction of mortality. Conclusions: PPROM before 26 weeks has a high morbidity and mortality, and the significant predictors of neonatal mortality and adverse outcomes were antibiotic prophylaxis, latency period, GA at birth and birth weight. Nevertheless, the only independent significant predictor of survival rate was birth weight.