Crecimiento físico y composición corporal de jóvenes beisbolistas brasileros por edad cronológica y estado de madurez / Physical growth and body composition of young Brazilian baseball players by chronological age and maturity stage

Introducción: El crecimiento físico (CF), maduración biológica (MB) y la composición corporal (CC) son indicadores de salud que deben ser controlados para detectar anomalías individuales y para la selección y detección de talentos deportivos. El objetivo fue verificar si los parámetros de CF y la CC de jóvenes beisbolistas deben ser analizados por estado de madurez antes que por edad cronológica como lo sugieren las investigaciones. Métodos: Se efectuó un estudio descriptivo transversal en102 niños y adolescentes Beisbolistas de 9.0 a 15.0 años. La selección de la muestra fue no probabilística (conveniencia). Se evaluó el peso, la estatura de pie, estatura sentada, pliegues tricipital, subscapular. Se calculó el estado de madurez por la técnica antropométrica de Mirwald. El porcentaje de grasa (%G), masa grasa (MG) y masa libre de grasa (MLG) fueron estimados por ecuaciones de regresión. Resultados: El promedio de edad cronológica fue de 12,2±2,2 años, el estado de madurez fue alcanzado a los 14,8±0,5APVC y los años de experiencia en la modalidad deportiva fue de 5,6±2,2 años. Se determinaron 5 niveles de estado de madurez: -4APVC, -3APVC, -2APVC, -1APVC Y 0APVC. Los niños clasificados como púberes reflejaron valores superiores de peso, estatura, MG y MLG en comparación con los pre púberes (p<0,05).Conclusión: El estudio demostró que la evaluación del estado de madurez en jóvenes beisbolistas por medio de una técnica antropométrica no-invasiva es esencial para disminuirlos factores de confusión ocasionados por la edad cronológica, principalmente cuando se estudia el CF y la CC durante la adolescencia. (AU)

Introduction: Physical growth (FC), biological maturation (BM) and body composition (BC) are health indicators that should be monitored to detect individual abnormalities and for the selection and detection of sports talent. The objective was to verify whether the parameters of FC and CC of young baseball players should be analyzed by maturity status rather than by chronological age as suggested by research. Methods: A descriptive cross-sectional study was carried out in 102 children and adolescent baseball players aged 9.0 to 15.0 years. The sample selection was non-probabilistic (convenience). Weight, standing height, sitting height, tricipital and subscapular folds were evaluated. Maturity status was calculated by the Mirwald anthropometric technique. Fat percentage (%G), fat mass (FM) and fat-free mass (FFM) were estimated by regression equations. Results: The average chronological age was 12.2±2.2 years, the maturity stage was reached at 14.8±0.5APVC and the years of experience in the sport modality was 5.6±2.2 years. Five levels of maturity status were determined: -4APVC, -3APVC, -2APVC, -1APVC and 0APVC. Children classified as pubertal reflected higher values of weight, height, MG and GLM compared to pre-pubertal (p<0.05). Conclusion: The study demonstrated that the evaluation of maturity status in young baseball players by means of a non-invasive anthropometric technique is essential to reduce the confounding factors caused by chronological age, mainly when CF and CC are studied during adolescence. (AU)

Geographical variability of patient characteristics and treatment patterns affect outcomes for incident hemodialysis patients.

BACKGROUND: Geographical differences in disease prevalence and mortality have been described in the general population and in chronic kidney disease patients in Europe. In this secondary analysis of the Membrane Permeability Outcome (MPO) study, we addressed differences in patient and treatment patterns, and whether these affect patient outcomes. METHODS: Participating countries were grouped according to geographical location; thus study centers in France, Greece, Italy, Portugal and Spain were allocated to southern Europe (n=499), and those in all other countries (Belgium, Germany, Poland and Sweden) to northern Europe (n=148). Descriptive analysis of patient and treatment patterns at study start, as well as survival analysis, was performed. RESULTS: In patients from the northern European countries, a higher prevalence of diabetes mellitus and of cardiovascular disease was observed than in those from southern Europe (diabetes 35.1% vs. 21.0%, p=0.0007; cardiovascular disease 40.5% vs. 22.8%, p<0.0001). In northern Europe, 23% of patients started hemodialysis with a catheter for vascular access, while in southern European centers, only 13% did so (p=0.0042). Kaplan-Meier survival analysis revealed a lower probability for both all-cause and cardiovascular mortality in southern Europe (log-rank test p<0.001). In a Cox proportional hazards model, a higher mortality risk was estimated for the northern European patients after adjustment for age, sex, membrane permeability, comorbidity index and vascular access (hazard ratio = 1.831; 95% confidence interval, 1.282-2.615; p=0.0009). CONCLUSIONS: Our study patients from northern Europe showed a higher risk profile than those from southern Europe. However, only some of the factors can be modified in attempts to lower the mortality risk in this geographical area.

Efficacy and safety of cinacalcet for the treatment of secondary hyperparathyroidism in patients with advanced chronic kidney disease before initiation of regular dialysis.

AIM: To evaluate the compassionate use of cinacalcet for the management of secondary hyperparathyroidism in patients who are not on dialysis. METHODS: Patients with stage 4-5 chronic kidney disease (CKD) who were not on dialysis, had an intact parathyroid hormone (iPTH) level greater than 300 pg/mL, and had not responded satisfactorily to treatment with phosphate binders and vitamin D were prospectively studied. Patients received 6 months of compassionate treatment with cinacalcet, which was initiated at a dose of 30 mg/day orally and flexibly dosed thereafter based on iPTH levels. RESULTS: Twenty-six patients with a mean age±standard deviation (SD) of 58.8±16.1 years were enrolled in the study and included in the statistical analysis. The mean percentage change in iPTH levels from baseline after 6 months of treatment was -67.9±17.0%, with 92.3% (95% confidence interval (CI), 75.9-97.9) of patients showing an iPTH level within the limits recommended by Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines. The mean serum calcium concentrations had decreased significantly at the end of the study (-8.0±6.9%), while the mean serum phosphorus concentration had significantly increased (+8.3±17.0%). CONCLUSION: Our results suggest that cinacalcet may be a useful alternative for the treatment of secondary hyperparathyroidism in pre-dialysis patients who are unresponsive to other treatments. The hypocalcemia and hyperphosphatemia reported in previous studies may not occur if a moderate dose of calcimimetics is used in patients with marginal glomerular filtration rates, especially if combined with vitamin D analogues and calcium-based phosphate binders.

Effect of acetate-free biofiltration with a potassium-profiled dialysate on the control of cardiac arrhythmias in patients at risk: a pilot study.

Cardiac arrhythmias are a frequent event in chronic hemodialysis patients. The aim of this study was to evaluate the efficacy and safety of acetate-free hemofiltration with potassium-profiled dialysate (AFB-K) dialysis compared with constant potassium acetate-free biofiltration (AFB). Twelve patients (mean age 79 years) affected by cardiac arrhythmias or at a high risk for arrhythmia (advanced age, hypertension, left ventricular hypertrophy, heart valve disease, coronary artery disease, diabetes, paroxysmal atrial fibrillation) participated in a single-center, sequential cohort study. All were treated with hemodialysis 3 times per week, using constant potassium AFB for the first 3 weeks, followed by an AFB-K dialysate for the subsequent 3 weeks. The hemofilter, duration of dialysis, and electrolyte concentration were the same in both treatments. Both AFB-K and constant potassium AFB dialytic techniques were safe and well tolerated. The results of biochemical tests were similar, except for serum potassium levels after 2 hr of dialysis, which were significantly higher in the AFB-K group (4.0 mmol/L) than in the constant potassium AFB group (3.6 mmol/L) (p<0.001). All cardiac variables improved during AFB-K dialysis. There was a significant reduction of postdialysis QT intervals corrected for heart rate in the AFB-K group (448.8 ms) compared with the constant potassium AFB group (456.8 ms) (p=0.039). The severity and mean number of ventricular extasystoles also decreased (163.5 vs. 444.5/24 hr). Potassium profiling during hemodialysis treatment may be beneficial for patients with arrhythmias or at those risk of arrhythmias, particularly those with predialysis hyperkalemia.

Use of pure bicarbonate-buffered peritoneal dialysis fluid reduces the incidence of CAPD peritonitis.

BACKGROUND: Advances in bag connection technology have reduced the incidence of peritonitis in CAPD patients but there is little information on the effect of the new peritoneal dialysis fluids. METHODS: We studied the incidence of CAPD peritonitis for about 3 years in 100 incident patients--50 patients dialysed with lactate-buffered solution, pH 5.5 and containing glucose degradation products (GDP) (lactate group), and 50 patients with pure bicarbonate-buffered solution, pH 7.4 and low GDP (bicarbonate group). Patients in both groups were similar in age, sex, length of time on CAPD, connection technology and handling of dialysis. RESULTS: In the lactate group, 74 episodes of peritonitis were recorded compared with 43 in the bicarbonate group, i.e. one episode per 21 patient-months with the lactate dialysis fluid and one episode per 36 patient-months with the bicarbonate dialysis fluid (OR 0.58, 95% CI 0.37-0.91, P = 0.017). A total of 3369 exchanges per episode of peritonitis were recorded for bicarbonate compared with 2004 exchanges per episode of peritonitis in the lactate group. The majority of organisms isolated in both groups were Gram-positive bacteria, with a predominance of the oropharyngeal and cutaneous endogenous flora. Three episodes of fungal peritonitis occurred in the lactate group and none in the bicarbonate group. CONCLUSIONS: Our results suggest that the pure bicarbonate-buffered peritoneal dialysis fluid appears to reduce the frequency of peritonitis in CAPD patients possibly in relation to greater biocompatibility and maintenance of peritoneal membrane structural integrity. Similar results can probably relate to all low-GDP solutions.

Long-term clinical experience with pure bicarbonate peritoneal dialysis solutions.

OBJECTIVES: The aim of this prospective study was to collect long-term experience in incident peritoneal dialysis (PD) patients treated with pure bicarbonate-buffered PD fluids. METHODS: The metabolic parameters acidosis, acid-base status, adequacy, fluid balance, nutritional markers, calcium, phosphorus, parathyroid hormone (PTH), and general laboratory work and medication were compared between incident PD patients in two groups: one treated with a 34 mmol/L bicarbonate-buffered PD fluid (BIC), the other with a 35 mmol/L lactate-buffered PD fluid (LAC). The observation period included 5 visits from 1 month (visit 1) until 12 months (visit 5) after the start of dialysis treatment. For the descriptive analysis, means and standard deviations were calculated. Student's t-test and linear mixed models were used to compare the two treatment groups. RESULTS: 36 patients were followed for 12 months, 18 in the BIC group and 18 in the LAC group. Statistically significant differences between the groups (at the end of study) were found. In BIC group, venous plasma bicarbonate was 27.4 +/- 2.3 mmol/L, base excess 0.8 +/- 2.2 mmol/L, and pH 7.31 +/- 0.05; in LAC group, venous bicarbonate was 25.9 +/- 2.4 mmol/L, base excess -0.6 +/- 2.1 mmol/L, and pH 7.30 +/- 0.04. No patient from the BIC group needed oral bicarbonate, in contrast to 4 patients in the LAC group. Whereas peritoneal urea and creatinine clearances did not differ between the groups, there was better renal solute clearance in the BIC group, accompanied by better-preserved diuresis at 12 months (1333 +/- 935 mL with BIC vs 839 +/- 556 mL with LAC). The reverse was true for ultrafiltration. CONCLUSIONS: Pure bicarbonate-buffered PD solutions were superior in correcting metabolic acidosis and they allowed omission of oral bicarbonate. The minor ultrafiltration with bicarbonate-buffered PD solutions was counterbalanced by better-preserved residual renal function with these solutions.

Online hemodiafiltration: 4 years of clinical experience.

Online hemodiafiltration (online HDF) is a new hemodialysis technique combining convection and diffusion and thus also enabling the purification of large molecules. As yet, only a small number of clinical experiences have been published about the effectiveness and safety of online HDF. We present a prospective and observational study conducted on 31 patients treated with online HDF in our center in the last 4 years. The purpose of the study is to compare the evolution of the following aspects before and after starting online HDF: dose of dialysis, purification of medium-sized/large molecules, inflammation, nutrition, Ca-P metabolism, anemia, and intradialytic complications. Online HDF increased Kt/V to 31.0% (p > 0.001) and reduced postdialysis beta(2)-M to 66.4% (p > 0.001). The rest of the parameters analyzed did not vary significantly. During online HDF, episodes of symptomatic hypotension fell by 45% in relation to conventional hemodialysis, and no relevant complication occurred. Online HDF is very useful in patients in whom we need to increase replacement therapy, such as patients with a large body surface, those in whom we suspect a residual syndrome or those who have been receiving dialysis for a long time and for whom we wish to prevent amyloidosis. Online HDF is safe and better tolerated than conventional hemodialysis.

Oral protein-energy supplements in peritoneal dialysis: a multicenter study.

BACKGROUND: Protein-energy malnutrition is prevalent in peritoneal dialysis (PD) patients and is associated with increased morbidity and mortality. OBJECTIVE: To evaluate the impact of prophylactic treatment with an oral protein-energy supplement (Protenplus; Fresenius AG, Bad Homburg, Germany) on nutritional parameters in patients starting PD. DESIGN: Prospective, multicenter, randomized study of group A patients (Protenplus, n = 35) and group B (controls, n = 30), with evaluations at baseline and at 6 and 12 months. STATISTICAL METHODS: Efficacy of factors by linear mixed model analysis for repeated measurements, chi-square, t-test, and Mann-Whitney test. OUTCOME PARAMETERS: Patient compliance, serum albumin, and other nutritional parameters. RESULTS: No significant differences were found at baseline evaluation. During follow-up, a significant number of group A patients abandoned intake of the supplement due to non-compliance (n = 7) or side effects (n = 8) (chi2 p < 0.01). Patients with lower residual renal function were less likely to comply. The mixed model in the "intention to treat" analysis showed a significant increase related to supplement intake only in total lymphocyte count in group A. The "as treated" analysis of the 29 patients who fulfilled the study (9 in group A, 20 in group B) disclosed that belonging to group A constituted an independent factor for increased lymphocyte count (p < 0.001), body weight (p < 0.03), tricipital skinfold thickness (p < 0.01), middle-arm muscle circumference (p < 0.025), lean body mass (LBM) (p < 0.002), creatinine LBM related to body surface area (p < 0.001), and creatinine generation rate (p < 0.002). However, these data may have been biased by the high rate of noncompliance in group A. CONCLUSIONS: Protenplus proved to be unsuitable as a long term, oral protein-energy supplement in PD patients due to a high rate of noncompliance and intolerance, primarily among patients with lower residual renal function. The question of whether other products, better-tolerated as nutritional supplements, could compensate for daily protein peritoneal losses in long-term PD remains open.

Erythropoietin requirements: a comparative multicenter study between peritoneal dialysis and hemodialysis.

BACKGROUND: The management of anemia with erythropoietin (EPO) is important in the global treatment of dialysis patients. There is a general impression that anemia control with EPO is obtained more easily in peritoneal dialysis (PD) patients than in hemodialysis (HD) patients. The EPO administration route has to be the same to compare the two techniques adequately. METHODS: To compare EPO action by subcutaneous (SC) route in HD and PD, 132 stable patients were recruited (HD: 69, PD: 63) from six centers, with adequate dialysis criteria (Kt/V in HD >1.3; weekly Kt/V in PD >1.8). In a cross-sectional study, the EPO dose/week, the number of EPO doses/week, hemoglobin (Hb), ferritin, transferrin saturation index (TS), albumin and intact parathyroid hormone (iPTH) were analyzed. Iron treatment, comorbidity and ACE inhibitors (ACEI) and angiotensin II antagonist (AIIA) treatment were recorded. A multivariate regression model was used in the statistical analysis. RESULTS: The mean Hb level was the same in both groups, HD 11.6 (1.3) g/dL, PD 11.4 (1.4) g/dL, p=0.3. The SC, EPO doses required to obtain the Hb levels were higher in HD than in PD patients, with a difference of 64.3 u/Kg/week, statistically significant in the multivariate regression model (p=0.001, 95% CI 42.6-86.0). The number of EPO doses/week was also higher in HD patients (65% of HD patients with > or = 3 doses, 19% of PD patients with three or more doses, p<0.001). TS was similar in both groups, while ferritin was higher in HD patients, with a higher percentage of HD patients using intravenous (i.v.) iron (HD 77% vs. PD 49%, p=0.001). Serum albumin and iPTH were lower in PD patients (p<0.001 and p=0.04, respectively), but the percentage of patients with intact parathyroid hormone (iPTH) >500 pg/mL was similar in both groups (HD 17%, PD 14%). CONCLUSIONS: With the same administration route, PD patients showed a reduced EPO requirement, and less frequent EPO administration than HD patients, to obtain the same Hb level. No other factors, except those involved in better depuration of erythropoiesis inhibitors in PD, seemed responsible for the different EPO requirements.

Calculo de una cubierta de madera para una terminal de buses en Trinidad

El presente proyecto plantea un cambio en la politica de construccion en nuestro pais. El capitulo uno se divide en dos partes, en la primera se hace una pequeña descripcion del proyecto arquitectonico para la terminal. En la segunda se da a conocer los antecedentes del proyecto y se exponen los datos que se requieren para un calculo estructural que vaya a efectuar para la ciudad de Trinidad. El capitulo tres comprende el calculo manual de la cubierta, considerando arcos biarticulados. En el capitulo cuarto se expone el resumen de una verificacion , via computacion. En el ultimo capitulo, se dan a conocer las conclusiones a las que se lleva tanto en calculo manual de la estructura como la verificacion computacional y la comparacion de ambos metodos de calculo.