Theoretical and experimental approach of fuel gas and carbon black production from coal tar pitch by thermal plasma process.

The processing of coal tar pitch (CTP) to produce clean fuel gas and carbon black (CB) is studied in a plasma reactor equipped with a direct-current plasma torch. The composition of the gas produced and energy costs were estimated theoretically for the CTP pyrolysis and gasification processes by two oxidants, namely oxygen and water vapor. We have found that the main gaseous compounds obtained in the pyrolysis and gasification processes are hydrogen (H2), carbon monoxide (CO), and very often carbon dioxide (CO2). For the pyrolysis case, the mean value of the synthesis gas concentration reaches a major value of 98 vol.% (H2 - 81 vol.%, CO - 17. vol.%). However, only 23% of the initial CTP is transformed into gas phase at 1100 K and its content increases up to 37.4% at a temperature of 3000 K. For oxygen gasification, the syngas quantity is little less compared to the pyrolysis case and attains 96.6 vol.% (H2 - 26.5 vol.%, CO - 70.1 vol.%) for T > 1100 K. An intermediate syngas content for the water steam gasification is 97.8 vol.% (with H2 - 55.8 vol.% and CO - 42.0 vol.%). The CB produced was composed of well-defined spherical particles of 30-nm size. Furthermore, it is composed of carbon (98.2%), and followed by oxygen (1.8%) with a surface area of 97 m2 g-1. The thermal plasma system shows high efficiency in conversion of CTP into high-value-added products.

Valoración del flujo de la fístula arteriovenosa en pacientes en tratamiento con quelantes con calcio / Evaluation of arteriovenous fistula blood flow in patients with calcium chelation therapy

No disponible

Electrochemical oxidation of imazapyr with BDD electrode in titanium substrate.

In this work we have studied the treatment of imazapyr by electrochemical oxidation with boron-doped diamond anode. Electrochemical degradation experiments were performed in a one-compartment cell containing 0.45 L of commercial formulations of herbicide in the pH range 3.0-10.0 by applying a density current between 10 and 150 mA cm(-2) and in the temperature range 25-45 °C. The maximum current efficiencies were obtained at lower current densities since the electrochemical system is under mass transfer control. The mineralization rate increased in acid medium and at higher temperatures. The treatment was able to completely degrade imazapyr in the range 4.6-100.0 mg L(-1), although the current charge required rises along with the increasing initial concentration of the herbicide. Toxicity analysis with the bioluminescent bacterium Vibrio fischeri showed that at higher pollutant concentrations the toxicity was reduced after the electrochemical treatment. To clarify the reaction pathway for imazapyr mineralization by OH radicals, LC-MS/MS analyses we performed together with a theoretical study. Ions analysis showed the formation of high levels of ammonium in the cathode. The main final products of the electrochemical oxidation of imazapyr with diamond thin film electrodes are formic, acetic and butyric acids.

Tratamiento con hemodiálisis larga con filtros de alto cut-off en la nefropatía por cilindros del mieloma: nuestra experiencia / Treatment by long haemodialysis sessions with high cut-off filters in myeloma cast nephropathy: our experience

El mieloma múltiple (MM) consiste en la proliferación incontrolada de células plasmáticas con producción de cantidades variables de inmunoglobulinas o sus cadenas. La insuficiencia renal aguda puede ser un síntoma del MM, y a veces su forma de presentación. Las cadenas ligeras libres circulantes (CLL) pueden dar lugar al fallo renal por la precipitación intratubular de ellas, causando una nefropatía por cilindros. El tratamiento del mieloma, una adecuada hidratación y la eliminación de CLL mediante técnicas de aféresis son los tratamientos admitidos actualmente para esta entidad. Se han intentado diversas técnicas de aféresis para intentar eliminar las CLL, siendo la hemodiálisis de larga duración con filtros para eliminar dichas cadenas ligeras (alto cut-off) la que se postula como el tratamiento más eficaz para la nefropatía del mieloma. MÉTODOS: Presentamos cinco casos de nefropatía de mieloma: tres con nefropatía por cilindros (NC) diagnosticada por biopsia renal y dos con alta probabilidad de NC (niveles de CLL > 500 mg/l) tratados con hemodiálisis larga con membrana de alto cut-off. Todos presentaban insuficiencia renal aguda, en cuatro de ellos con necesidad de terapia sustitutiva y uno en situación de insuficiencia renal avanzada. En todos ellos los niveles de CLL fueron muy elevados. Recibieron tratamiento específico para el mieloma más hemodiálisis de alto cut-off hasta alcanzar niveles de CLL < 500 mg/l. RESULTADOS: Cuatro de los cinco pacientes recuperaron función renal, quedando independientes de diálisis. El tiempo de evolución del mieloma desde el inicio de la clínica fue variable (1-6 m). El número de sesiones varió entre 8-16. El paciente de más tiempo de evolución precisó más sesiones y no recuperó función renal. CONCLUSIONES: La hemodiálisis larga con filtros de alto cut-off más tratamiento con quimioterapia del mieloma parece ser un tratamiento eficaz en la insuficiencia renal aguda debida a nefropatía del mieloma. La precocidad en el inicio del tratamiento puede ser un factor determinante de la respuesta

Multiple myeloma (MM) is the uncontrolled proliferation of plasma cells with variable amounts of production of immunoglobulin or their chains. Acute renal failure can be a symptom of MM, and it is sometimes their presentation form. Circulating free light chains (FLC) could led to renal failure by intratubular precipitation of themselves causing a cast nephropathy. Myeloma's treatment, an adequate hydration and FLC's elimination by aphaeresis treatments are currently eligible therapy for this entity. Several aphaeresis techniques have been tried to eliminate the FLC being long-term hemodialysis with filters to remove these light chains (High Cut-Off filters). This treatment is postulated as the most effective treatment for myeloma nephropathy. METHODS: We report 5 cases of myeloma nephropathy: three of them with cast nephropathy (CN) diagnosed by renal biopsy and another two with high probability of NC (FLC levels >500mg/L). All of them were treated by hemodialysis with membrane high Cut-Off. The five patients had had an acute renal failure; in four of them need replacement renal therapy. The fifth patient only had an advanced renal failure. In all patients, FLC levels were very high. All patients received specific treatment for myeloma in addiction on hemodialysis high Cut-Off until the FLC levels were <500mg/ L. RESULTS: Four of the five patients recovered renal function, being independent of dialysis. The evolution time of myeloma since the first symptoms appeared was variable (1-6 months). The number of treatment sessions ranged from 8-16. The patient whose evolution time was the longest one required more sessions and did not recovered the renal function. CONCLUSIONS: Length hemodialysis with filters high cut-off plus specific myeloma chemotherapy seems to be an effective treatment in acute renal failure due to cast myeloma. The early initiation of treatment could be an important factor for the response

Treatment by long haemodialysis sessions with high cut-off filters in myeloma cast nephropathy: our experience.

UNLABELLED: Multiple myeloma (MM) is the uncontrolled proliferation of plasma cells with variable amounts of production of immunoglobulins or their chains. Acute renal failure can be a symptom of MM, and it is sometimes its form of presentation. Circulating free light chains (FLC) could lead to renal failure due to their intratubular precipitation, causing a cast nephropathy. The treatment of myeloma, adequate hydration and the removal of FLC by apheresis techniques are currently the treatments that are accepted for this disease. Several apheresis techniques have been attempted for the removal of FLC, with long haemodialysis sessions with filters for the removal of these light chains (high cut-off filters) being proposed as the most effective treatment for myeloma nephropathy. METHODS: We report 5 cases of myeloma nephropathy: three had cast nephropathy (CN) diagnosed by renal biopsy and the other two had a high probability of CN (FLC levels >500 mg/l). They were treated with long haemodialysis sessions with a high cut-off membrane. All patients had suffered acute renal failure; four required renal replacement therapy and one patient had advanced renal failure. In all patients, FLC levels were very high. They received specific treatment for myeloma in addition to high cut-off haemodialysis until they achieved FLC levels of <500 mg/l. RESULTS: Four of the five patients recovered renal function, and became independent of dialysis. The progression time for myeloma from the time the first symptoms appeared varied (1-6 months). The number of treatment sessions ranged from 8-16. The patient with the longest progression time required more sessions and did not recover renal function. CONCLUSIONS: Long haemodialysis sessions with high cut-off filters in addition to specific myeloma chemotherapy seems to be an effective treatment for acute renal failure due to myeloma nephropathy. The early initiation of treatment could be a determining factor for the response.

Incidencia del infarto agudo de miocardio en la evolución de los pacientes en tratamiento con diálisis / Incidence of acute myocardial infarction in the evolution of dialysis patients

Introducción: Aunque la frecuencia de la enfermedad coronaria (EAC) en los pacientes en diálisis se estima muy elevada, existe una gran variabilidad en los estudios en la tasa de infarto agudo de miocardio (IAM). Objetivo: Establecer la incidencia IAM y analizar sus características y repercusión en la evolución de los pacientes incidentes en diálisis. Métodos: Estudiamos los pacientes incidentes en diálisis entre el 1/1/1999 y el 31/12/2007, y analizamos la presentación del primer IAM en diálisis. Valoramos diagnósticos previos de diabetes, hipertensión arterial, EAC (IAM o lesiones en coronariografía), accidente cerebrovascular isquémico, arteriopatía periférica avanzada y tabaquismo. Se analizaron urea, creatinina, hematocrito, calcio/fósforo, hormona paratiroidea intacta, lípidos y albúmina. El seguimiento fue hasta trasplante, muerte, pérdida o cierre del estudio el 31/12/2010. Resultados: De 576 pacientes incluidos (64,6 ± 16 años; 24,7% diabéticos; 82,3% hemodiálisis/17,7% diálisis peritoneal), 34 (5,9%) (..) (AU)

Background: Although the estimated frequency of coronary artery disease (CAD) in patients on dialysis is very high, there is considerable variation in the studies published to date regarding the rate of acute myocardial infarction (AMI) in these patients. Objective: To establish the incidence of AMI and to analyse the characteristics and consequences of this entity on the clinical progression of incident dialysis patients. Methods: We recorded AMI in the patients treated in our dialysis unit between 01/01/1999 and 31/12/07. The variables assessed were: prior diagnosis of diabetes, hypertension, CAD (AMI or lesions observed in coronary angiography), ischaemic cerebrovascular accident, advanced peripheral artery disease (PAD), atrial fibrillation and tobacco use. Biochemical analyses included: urea, creatinine, haematocrit, calcium, phosphorous, iPTH, lipids and albumin. Follow-up lasted until transplant, death, loss to follow-up or study end in Dec. 2010. Results: Of the 576 patients recruited (aged 64.6±16 years), 24.7% had diabetes, 82.3% were on haemodialysis (17.7% on peritoneal dialysis), and 34 (5.9%) had a previous diagnosis of CAD. In a follow-up lasting a mean of 40.2±32 months (1931.5 patient-years), 40 patients (6.9%) suffered an AMI. The incidence was 2.13/100 patient-years. The patients without CAD had an incidence of 1.84/100 patient-years and those with a previous (..) (AU)

Incidence of acute myocardial infarction in the evolution of dialysis patients.

BACKGROUND: Although the estimated frequency of coronary artery disease (CAD) in patients on dialysis is very high, there is considerable variation in the studies published to date regarding the rate of acute myocardial infarction (AMI) in these patients. OBJECTIVE: To establish the incidence of AMI and to analyse the characteristics and consequences of this entity on the clinical progression of incident dialysis patients. METHODS: We recorded AMI in the patients treated in our dialysis unit between 01/01/1999 and 31/12/07. The variables assessed were: prior diagnosis of diabetes, hypertension, CAD (AMI or lesions observed in coronary angiography), ischaemic cerebrovascular accident, advanced peripheral artery disease (PAD), atrial fibrillation and tobacco use. Biochemical analyses included: urea, creatinine, haematocrit, calcium, phosphorous, iPTH, lipids and albumin. Follow-up lasted until transplant, death, loss to follow-up or study end in Dec. 2010. RESULTS: Of the 576 patients recruited (aged 64.6 ± 16 years), 24.7% had diabetes, 82.3% were on haemodialysis (17.7% on peritoneal dialysis), and 34 (5.9%) had a previous diagnosis of CAD. In a follow-up lasting a mean of 40.2 ± 32 months (1931.5 patient-years), 40 patients (6.9%) suffered an AMI. The incidence was 2.13/100 patient-years. The patients without CAD had an incidence of 1.84/100 patient-years and those with a previous diagnosis of CAD had an incidence of 7.53/100 patient-years. In 22.5% of patients, AMI happened in the first 3 months of dialysis, and 37.5% in the 1st year. Of the 40 AMI, 15 were with ST-segment elevation (incidence: 0.79/100 patient-years) and 25 were non ST-segment elevation (incidence: 1.33/100 patient-years). The factors that predicted the occurrence of AMI in dialysis were older age (OR: 1.037; 95% CI: 1.009-1.067; P=.011), previous CAD (OR: 3.35; 95% CI: 1.48-7.16; P=.004), and diabetes as a cause of nephropathy (OR: 2.96; 95% CI: 1.49-5.86; P=.002). In-hospital mortality was 30%, with 72.5% of deaths occurring in the 1st year and 82.5% in the 2nd; 80% of the patients who underwent a coronary angiography had multi-vessel disease. CONCLUSIONS: The incidence of AMI in incident dialysis patients is high. In previous coronary disease patients, the incidence is 3-fold higher. Post-infarction mortality is very high and multi-vessel disease is very frequent.

A comparative study of the electrochemical oxidation of the herbicide tebuthiuron using boron-doped diamond electrodes.

The thiadiazolylurea derivative tebuthiuron (TBH) is commonly used as an herbicide even though it is highly toxic to humans. While various processes have been proposed for the removal of organic contaminants of this type from wastewater, electrochemical degradation has shown particular promise. The aim of the present study was to investigate the electrochemical degradation of TBH using anodes comprising boron-doped (5000 and 30,000 ppm) diamond (BDD) films deposited onto Ti substrates operated at current densities in the range 10-200 mA cm(-2). Both anodes removed TBH following a similar pseudo first-order reaction kinetics with k(app) close to 3.2 × 10(-2) min(-1). The maximum mineralization efficiency obtained was 80%. High-pressure liquid chromatography with UV-VIS detection established that both anodes degraded TBH via similar intermediates. Ion chromatography revealed that increasing concentrations of nitrate ions (up to 0.9 ppm) were formed with increasing current density, while the formation of nitrite ions was observed with both anodes at current densities ≥ 150 mA cm(-2). The BDD film prepared at the lower doping level (5000 ppm) was more efficient in degrading TBH than its more highly doped counterpart. This unexpected finding may be explained in terms of the quantity of impurities incorporated into the diamond lattice during chemical vapor deposition.

Anodic oxidation of wastewater containing the Reactive Orange 16 Dye using heavily boron-doped diamond electrodes.

Boron-doped diamond (BDD) films grown on the titanium substrate were used to study the electrochemical degradation of Reactive Orange (RO) 16 Dye. The films were produced by hot filament chemical vapor deposition (HFCVD) technique using two different boron concentrations. The growth parameters were controlled to obtain heavily doped diamond films. They were named as E1 and E2 electrodes, with acceptor concentrations of 4.0 and 8.0 × 10(21)atoms cm(-3), respectively. The boron levels were evaluated from Mott-Schottky plots also corroborated by Raman's spectra, which characterized the film quality as well as its physical property. Scanning Electron Microscopy showed well-defined microcrystalline grain morphologies with crystal orientation mixtures of (111) and (100). The electrode efficiencies were studied from the advanced oxidation process (AOP) to degrade electrochemically the Reactive Orange 16 azo-dye (RO16). The results were analyzed by UV/VIS spectroscopy, total organic carbon (TOC) and high-performance liquid chromatography (HPLC) techniques. From UV/VIS spectra the highest doped electrode (E2) showed the best efficiency for both, the aromaticity reduction and the azo group fracture. These tendencies were confirmed by the TOC and chromatographic measurements. Besides, the results showed a direct relationship among the BDD morphology, physical property, and its performance during the degradation process.

How do disorders related to hospitalisation influence haemodialysis patients' nutrition?

INTRODUCTION: Hospitalizations are frequent in hemodialysis patients and is often accompanied by nutritional deterioration showed by a loss of weight and a reduction of albumin serum levels. This phenomenon is related with length of stay having its origin in a complex interplay of factors. Our aim in this study was to analyze if changes in body weight and other nutritional parameters are influenced by the illnesses presented during hospitalization. PATIENTS AND METHODS: Over a period of three years, we retrospectively chose chronic haemodialysis patients that were admitted for more than four days, excluding those cases that died in the hospital. We randomly chose one admission episode per patient so as to avoid excessive weighing of repeated admissions. We took data concerning weight changes, pre-admission and post-discharge analytical results, analytical results following first week of hospital stay, disorders causing hospital admission and those that developed during the hospital stay. We created a point score system to record the total of illnesses presented. RESULTS: The study included 77 patients, aged 67±12 years and having undergone haemodialysis for 31±34 months. Hospital stay was 17.8±12.6 days (median, 12 days). We observed that many patients admitted for digestive and osteoarticular disorders, heart failure or coronary syndrome lost more weight during their hospital stay, although no significant differences were reached. The total number of disorders suffered during the hospital stay was independent of the cause of hospitalisation. Anaemia,heart arrhythmias and signs of heart failure were associated with longer hospital stays, however it was only anaemia that was significantly related to greater weight loss. Weight loss was not related to surgery or infections. Albumin levels during the first week of hospital stay were different depending on the disorder upon admission. It was lower when the patients were admitted for digestive disorders (ANOVA, P=.05). Changes in albumin and creatinine levels before and after the hospital stay did not differ among disorders. We observed a relationship between having presented with more disorders during the stay and a longer stay, lower initial albumin and greater weight loss following discharge. In the multivariate analysis, we found the following weight loss predictors: stay, anaemia, and sepsis. We also found the following hospital stay predictors:Charlson's comorbidity index, heart arrhythmias, anaemia, sepsis and surgery. CONCLUSIONS: Malnutrition during the hospital stay depends on the duration and the number of disorders that develop during this time, the cause of admission having less impact on this. Albumin levels decrease earlier in patients that are going to develop more disorders during hospital stay.

Análisis de la eficacia y de los factores que influyen en la respuesta del hiperparatiroidismo secundario de pacientes en hemodiálisis a cinacalcet / Analysis of the efficacy and factors influencing the response of secondary hyperparathyroidism patients on hemodialysis to cinacalcet

Introducción: Aunque el cinacalcet ha mejorado el control del hiperparatiroidismo secundario en hemodiálisis, todavía un 50% de los pacientes no alcanzan las cifras de PTH recomendadas por las guías K/DOQI. El objetivo de este estudio fue analizar la eficacia del tratamiento del hiperparatiroidismo secundario con cinacalcet en pacientes no seleccionados en hemodiálisis crónica, de acuerdo con los objetivos marcados por las guías K/DOQI y KDIGO. Además, investigamos qué factores pueden influir en el grado de respuesta del hiperparatiroidismo secundario a cinacalcet. Material y métodos: Recogimos retrospectivamente la evolución de 74pacientes en hemodiálisis con hiperparatiroidismo secundario que fueron tratados con cinacalcet durante al menos 6 meses. Resultados: De acuerdo con las guías K/DOQI, la proporción de pacientes con PTHi >300 pg/ml se redujo al 50%, la presencia de hiperfosforemia descendió del 38,4 al 23,3% y el producto Ca x P >55 mg2/dl2 bajó de 37,8 a 15,1%. La prevalencia de hipocalcemia aumentó de 2,7 al 12,3%. Con respecto a las guías KDIGO, la proporción con PTHi >600 pg/mlse redujo desde 41,1 al 16,4% y la de hiperfosforemia del68,5 al 52,1%; pero al considerar a pacientes con PTHi inicial>600 pg/ml, la prevalencia de P >4,5 mg/dl descendió de 83,3 del 55,2%. Observamos un incremento de la dosis de carbonato cálcico (basal 0,61 ± 1,53 g de calcio elemento/día frente a final 0,95 ± 1,98 g de calcio elementto/día; p = 0,03), debido más a la hipocalcemia que a la necesidad de quelar el fósforo. Encontramos menores descensos de la PTHi entre los pacientes que tenían prescrito inicialmente más sevelamer, y al final del seguimiento presentan mayores niveles séricos de PTHi (no sevelamer: 312 ± 245 pg/ml; sevelamer < _ 6,4 g/día: 510 ± 490 pg/ml; sevelamer >6,4 g/día: 526 ± 393 pg/ml; p = 0,04) y de fósforo (no sevelamer: 4,5 ± 1,2 mg/dl; sevelamer < _ 6,4 g/día: 4,2 ± 1,5 mg/dl; sevelamer >6,4 g/día: 5,7 ± 0,9 mg/dl; p = 0,01). El tratamiento asociado con paricalcitol no mostró ninguna in- fluencia en el grado de respuesta. Los pacientes que alcanzaron los objetivos de PTH mostraron ya a los 3 meses de tratamiento un mayor descenso en los niveles séricos de PTHi (159 ± 84 frente a 630 ± 377 pg/ml; p <0,001), con dosis significativamente menores de cinacalcet (33,8 ± 22,5 frente a 51,1 ± 25,1 mg/día; p = 0,003). Con análisis multivariante, el grado de reducción de la PTHi dependió de sus cifras séricas iniciales y de la dosis inicial de sevelamer. Conclusiones: Ci- nacalcet mejora el control del hiperparatiroidismo secunda- rio, si bien la respuesta es menor en los casos de mayor gra- vedad, representados por niveles más altos de PTH y mayores dosis iniciales de sevelamer. Por el contrario, un descenso im- portante de PTH a los 3 meses con dosis relativamente bajas de cinacalcet sería un marcador pronóstico de buena respuesta (AU)

Background: Treatment of secondary hyperparathyroidism with cinacalcet improves control of PTH, phosphorus, calcium and Ca X P product, enabling to achieve targets recommended by K/DOQI guidelines for PTHi in only 30-50%of patients, in studies with a very selected population. The aim of this study was to analyze its effectiveness in real clinical practice, comparing results with targets recommended by K/DOQI and KDIGO guidelines and to investigate factors having influence on PTH responsiveness to cinacalcet. Methods: We collected data of evolution of 74 patients on hemodialysis with secondary hyperparathyroidism who were treated with cinacalcet for at least 6months. Results: According K/DOQI targets we observed a reduction of proportion of patients with PTHi >300 pg/mlto 50%, a decrease of hyperphosphoremia from 38.4% to23.3% and proportion of patients with Ca x P product >55mg2/dl2 from 37.8% to 15.1%. By contrast, presence of hypocalcemia increases from 2.7% to 12.3%. Comparing with KDIGO targets, proportion of patients with PTHi >600pg/ml decreased from 41.1% to 16.4% and with hyperphosphoremia from 68.5% to 52.1%. However, when considering patients with baseline PTHi >600 pg/ml prevalence of P >4.5 mg/dl decreased from 83.3% to 55.2%. We observed significant changes of phosphate binders after cinacalcet treatment with an increase in calcium carbonate doses (pre 0.61 ± 1.53 g of calcium/day vs post-cinacalcet (..) (AU)

[Analysis of the efficacy and factors influencing the response of secondary hyperparathyroidism patients on hemodialysis to cinacalcet]. / Análisis de la eficacia y de los factores que influyen en la respuesta del hiperparatiroidismo secundario de pacientes en hemodiálisis a cinacalcet.

BACKGROUND: Treatment of secondary hyperparathyroidism with cinacalcet improves control of PTH, phosphorus, calcium and Ca x P product, enabling to achieve targets recommended by K/DOQI guidelines for PTHi in only 30-50% of patients, in studies with a very selected population. The aim of this study was to analyze its effectiveness in real clinical practice, comparing results with targets recommended by K/DOQI and KDIGO guidelines and to investigate factors having influence on PTH responsiveness to cinacalcet. METHODS: We collected data of evolution of 74 patients on hemodialysis with secondary hyperparathyroidism who were treated with cinacalcet for at least 6 months. RESULTS: According K/DOQI targets we observed a reduction of proportion of patients with PTHi > 300 pg/ml to 50%, a decrease of hyperphosphoremia from 38.4% to 23.3% and proportion of patients with Ca x P product > 55 mg2/dl2 from 37.8% to 15.1%. By contrast, presence of hypocalcemia increases from 2.7% to 12.3%. Comparing with KDIGO targets, proportion of patients with PTHi > 600 pg/ml decreased from 41.1% to 16.4% and with hyperphosphoremia from 68.5% to 52.1%. However, when considering patients with baseline PTHi > 600 pg/ml prevalence of P > 4.5 mg/dl decreased from 83.3% to 55.2%. We observed significant changes of phosphate binders after cinacalcet treatment with an increase in calcium carbonate doses (pre 0.61 +/- 1.53 g of calcium/day vs post-cinacalcet 0.95 +/- 1.98 g of calcium/day; p = 0.03) that was prescribed to prevent hypocalcemia and not as phosphate binder. Responsiveness were lower in patients who were taking higher doses of sevelamer at baseline, showing at the end of the study higher PTHi (no-sevelamer: 312 +/- 245 pg/ml; sevelamer < 6.4 g/day: 510 +/- 490 pg/ml; sevelamer > 6.4 g/day: 526 +/- 393 pg/ml; p = 0.04) and phosphorus (no-sevelamer: 4.5 +/- 1.2 mg/dl; sevelamer < 6.4 g/day: 4.2 +/- 1.5 mg/dl; sevelamer > 6.4 g/day: 5.7 +/- 0.9 mg/dl; p=0.01) serum levels. Use of paricalcitol did not show any influence on PTH response. Patients achieving targets for PTH at the end of the study showed a good response early, with a significant decrease of PTHi levels at three months (159 +/- 84 vs 630 +/- 377 pg/ml; p < 0.001) with significantly lower doses of cinacalcet (33.8 +/- 22.5 vs 51.1 +/- 25.1 mg/day; p = 0.003). Using multivariate analysis we found that percent of PTHi reduction was related with baseline PTHi levels and taking sevelamer as phosphate binder at baseline. CONCLUSION: Use of cinacalcet improves grade of control of secondary hyperparathyroidism in non-selected patients in hemodialysis, showing poor response in population with higher PTHi levels and who takes higher doses of sevelamer at baseline. By contrast, a reduction of PTHi levels at 3 months of treatment with relatively lower doses is a pronostic marker of good response to cinacalcet treatment.

Proteinuria en rangonefrótico en paciente con síndrome antifosfolípido primario / No disponible

No disponible

A novel procedure to obtain nanocrystalline diamond/porous silicon composite by chemical vapor deposition/infiltration processes.

Nanocrystalline diamond (NCD) films were formed on porous silicon (PS) substrate by Chemical Vapor Deposition/Infiltration (CVD/CVI) process using a hot filament reactor. This innovative procedure is determinant to grow a controlled three-dimensional diamond structure with diamond grains formation in the pores, covering uniformly the different growth planes. In this CVI process, a piece of reticulated vitreous carbon (RVC) was used, under de PS substrate, as an additional solid source of hydrocarbon that ensures the production of pertinent carbon growth species directly on PS and into its pores. PS substrates were obtained by anodization etching process of n-type silicon wafer in a hydrofluoric acid (HF) solution containing acetonitrile (CH3CN) which result in an uniform and well controlled porous distribution and size when compared with the usual ethanol solution. Depositions were performed using Ar-H2-CH4 where the methane concentration varied from 0 up to 1.0 vol%, to analyze the influence of RVC use as an additional carbon source on growth mechanism. Scanning Electron Microscopy (SEM) and Field Emission Gun (FEG) were used to investigate PS and NCD film morphology. SEM images of NCD showed faceted nanograins with average size from 5 to 16 nm and uniform surface texture covering all the supports among the pores resulting in an apparent micro honeycomb structure. Raman spectra confirmed the existence of sp2-bonded carbon at the grain boundaries. The spectra showed a peak that may be deconvoluted in two components at 1332 cm(-1) (diamond) and 1345 cm(-1) (D band). Two shoulders at 1150 and 1490 cm(-1) also appear and are assigned to transpolyacetylene (TPA) segments at the grain boundaries of NCD surfaces. In addition, X-ray diffraction analyses of all films presented characteristic diamond diffraction peaks corresponding to (111), (220) and (311).

[Conservative therapy of hemorrhoids]. / Terapia conservativa delle emorroidi.

Conservative therapy of hemorrhoids can be curative at stage I and II of disease; further it rappresent a valid preliminary management for a better result of more aggressive treatments, be they surgical or not. Beside local and general drugs other aspects play an important role in conservative therapy of hemorrhoids: adequate local hygiene, correct diet, education to a physiological evacuation and last but not least stool frequency regulation.

Non-occupational recurrent bilateral pneumoparotitis in an adolescent.

This is a case report of recurrent bilateral parotid swelling with intraglandular gaseous bubbles in a 14-year-old boy, together with a review of the literature on this condition, which is usually called pneumoparotitis. The disorder has been reported as an occupational hazard in wind instrument players and glass-blowers and also as a rare non-occupational disease, mainly in adolescents and often associated with psychological problems.