The European intercomparison of in-vivo monitoring laboratories: the EIVIC-2020 project

The EIVIC project was launched in 2020, and the main goal was the organisation of a European intercomparison of in-vivo monitoring laboratories dealing with direct measurements of gamma-emitting radionuclides incorporated into the body of exposed workers. This project was organised jointly by members of EURADOS Working Group 7 on internal dosimetry (WG7), the Federal Office for Radiation Protection (BfS, Germany) and the Radioprotection and Nuclear Safety Institute (IRSN, France). The objective was to assess the implementation of individual-monitoring requirements in EU Member States on the basis of in-vivo measurements and to gain insight into the performance of in-vivo measurements using whole-body counters. In this context, a total of 41 in-vivo monitoring laboratories from 21 countries, together with JRC (EC) and IAEA participated. The results were submitted in terms of activity (Bq) of the radionuclides identified inside phantoms that were circulated to all participants. The measured data were compared with reference activity values to evaluate the corresponding bias according to the standards ISO 28218 and ISO 13528. In general, the results of the different exercises are good, and most facilities are in conformity with the criteria for the bias and z-scores in the ISO standards. Furthermore, information about technical and organisational characteristics of the participating laboratories was collected to test if they had a significant influence on the reported results.

Use of Generic Antiretroviral Drugs and Single-Tablet Regimen De-Simplification for the Treatment of HIV Infection in Spain

The present study sought to describe the use of generic drugs and single-tablet regimen (STR) de-simplification for the treatment of human immunodeficiency virus (HIV) infection among 41 hospitals from the cohort of the Spanish HIV/AIDS Research Network (CoRIS). In June 2018, we collected information on when generic antiretroviral drugs (ARVs) were introduced in the different hospitals, how the decisions to use them were made, and how the information was provided to the patients. Most of the nine available generic ARVs in Spain by June 2018 had been introduced in at least 85% of the participating hospitals, except for zidovudine (AZT)/lamivudine (3TC) and AZT. The time difference between the effective marketing date of each generic ARV and its first dispensing date in the hospitals was much shorter for the more recently approved generic ARV since the year 2017. However, only up to 20% of the hospitals de-simplified efavirenz (EFV)/tenofovir disoproxil (TDF)/emtricitabine (FTC), dolutegravir (DTG)/abacavir (ABC)/3TC, and rilpivirine (RPV)/TDF/FTC (to generic EFV+TDF/FTC, DTG+generic ABC/3TC, and RPV+generic TDF/FTC, respectively), whereas the generic STR EFV/TDF/FTC was introduced in 87.8% of the centers. The median times between the date of effective marketing of generic TDF/FTC and the date of de-simplification of EFV/TDF/FTC and RPV/TDF/FTC were 723 [interquartile range (IQR): 369-1,119] and 234 (IQR: 142-264) days, respectively; this time was 155 (IQR: 28-287) days for de-simplification of DTG/ABC/3TC. In conclusion, despite the widespread use of generic ARVs, STRs de-simplification was only undertaken in <20% of the hospitals. There was wide variability in the timing of the introduction of each generic ARV after they were available in the market.

Effectiveness of the combination elvitegravir/cobicistat/tenofovir/emtricitabine (EVG/COB/TFV/FTC) plus darunavir among treatment-experienced patients in clinical practice: a multicentre cohort study

BACKGROUND

The aim of this study was to investigate the effectiveness and tolerability of the combination elvitegravir/cobicistat/tenofovir/emtricitabine plus darunavir (EVG/COB/TFV/FTC + DRV) in treatment-experienced patients from the cohort of the Spanish HIV/AIDS Research Network (CoRIS).

METHODS

Treatment-experienced patients starting treatment with EVG/COB/TFV/FTC + DRV during the years 2014-2018 and with more than 24 weeks of follow-up were included. TFV could be administered either as tenofovir disoproxil fumarate or tenofovir alafenamide. We evaluated virological response, defined as viral load (VL) < 50 copies/ml and < 200 copies/ml at 24 and 48 weeks after starting this regimen, stratified by baseline VL (< 50 or ≥ 50 copies/ml at the start of the regimen).

RESULTS

We included 39 patients (12.8% women). At baseline, 10 (25.6%) patients had VL < 50 copies/ml and 29 (74.4%) had ≥ 50 copies/ml. Among patients with baseline VL < 50 copies/ml, 85.7% and 80.0% had VL < 50 copies/ml at 24 and 48 weeks, respectively, and 100% had VL < 200 copies/ml at 24 and 48 weeks. Among patients with baseline VL ≥ 50 copies/ml, 42.3% and 40.9% had VL < 50 copies/ml and 69.2% and 68.2% had VL < 200 copies/ml at 24 and 48 weeks. During the first 48 weeks, no patients changed their treatment due to toxicity, and 4 patients (all with baseline VL ≥ 50 copies/ml) changed due to virological failure.

CONCLUSIONS

EVG/COB/TFV/FTC + DRV was well tolerated and effective in treatment-experienced patients with undetectable viral load as a simplification strategy, allowing once-daily, two-pill regimen with three antiretroviral drug classes. Effectiveness was low in patients with detectable viral loads.

METHODOLOGY AT CIEMAT WHOLE BODY COUNTER FOR IN VIVO MONITORING OF RADIOIODINE IN THE THYROID OF EXPOSED POPULATION IN CASE OF NUCLEAR EMERGENCY

Iodine-131 is one of the main concerns from the point of view of radiological protection in a short term after a nuclear accident. The WBC Laboratory of CIEMAT has developed a methodology for in vivo monitoring of radioiodine in the thyroid of exposed individuals in case of emergency. Thyroid-neck phantoms of different sizes are required for calibrating the detection systems in appropriate counting geometries for the measurement of exposed population. A Low-Energy Germanium (LEGe) detector and a Fastscan Counter were calibrated using a set of thyroid phantoms fabricated by CIEMAT. Each neck phantom consists of a Lucite cylinder with a vial source of 131I. Counting efficiencies depending on age and thyroid sizes were obtained to be used to determine the activity of 131I in internally contaminated people. DL of 131I varies with the age, being in the range of 5-8 Bq for the LEGe detector and 26-42 Bq for the Fastscan. Detection of intakes resulting in Committed Effective doses far below 1 mSv are guaranteed for thyroid monitoring in a few days after the accidental exposure assuming a scenario of acute inhalation or ingestion of 131I by members of the public.

THE CHALLENGE OF CIEMAT INTERNAL DOSIMETRY SERVICE FOR ACCREDITATION ACCORDING TO ISO/IEC 17025 STANDARD, FOR IN VIVO AND IN VITRO MONITORING AND DOSE ASSESSMENT OF INTERNAL EXPOSURES

The accreditation of an Internal Dosimetry Service (IDS) according to ISO/IEC 17025 Standard is a challenge. The aim of this process is to guarantee the technical competence for the monitoring of radionuclides incorporated in the body and for the evaluation of the associated committed effective dose E(50). This publication describes the main accreditation issues addressed by CIEMAT IDS regarding all the procedures involving good practice in internal dosimetry, focussing in the difficulties to ensure the traceability in the whole process, the appropriate calculation of detection limit of measurement techniques, the validation of methods (monitoring and dose assessments), the description of all the uncertainty sources and the interpretation of monitoring data to evaluate the intake and the committed effective dose.

EFFICIENCY STUDY OF A LEGe DETECTOR SYSTEM FOR THE ASSESSMENT OF 241Am IN SKULL AT CIEMAT WHOLE BODY COUNTER

(241)Am incorporation due to an incident or chronic exposure causes an internal dose, which can be evaluated from the total activity of this isotope in the skeleton several months after the intake. For this purpose, it is necessary to perform in vivo measurements of this bone-seeker radionuclide in appropriate counting bone geometries with very low attenuation of surrounded tissue and to extrapolate to total activity in the skeleton (ICRP 89, Basic anatomical and physiological data for use in radiological protection: reference values. 2001. 265). The work here presented refers to direct measurements of americium in the Cohen skull phantom at the CIEMAT Whole Body Counter (WBC) using low-energy germanium (LEGe) detectors inside a shielding room. The main goal was to determinate the most adequate head counting geometry for the in vivo detection of americium in the bone. The calibration of the in vivo LEGe system was performed with four detectors with 2 cm of distance to Cohen phantom. Two geometries were measured, on junction of frontal to parietal bones and frontal bone. The efficiencies are very similar in both geometries, the preferred counting geometry is the most comfortable for the person, with the LEGe detectors in the highest part of the frontal bone, near the junction with the parietal bone, CIEMAT WBC participated in a skull intercomparison exercise organised by WG7 of EURADOS (European Radiation Dosimetry Group e.V.). Efficiencies using three different skull phantoms were obtained. Measurements were performed for different head counting positions, four of them in the plane of symmetry and others over the temporal bone. The detector was placed in parallel with the calibration phantom at a distance of 1 cm. The main gamma emission of (241)Am, 59.5 keV (36 %), was used for comparing efficiency values. The lower efficiency was obtained over the frontal and occipital bones. Measurement with one LEGe detector over the parietal bone is the most efficient. The activity of each skull phantom was calculated using CIEMAT head calibration. Results of the EURADOS intercomparison are presented here for discussion.

EURADOS intercomparison on measurements and Monte Carlo modelling for the assessment of americium in a USTUR leg phantom

A collaboration of the EURADOS working group on 'Internal Dosimetry' and the United States Transuranium and Uranium Registries (USTUR) has taken place to carry out an intercomparison on measurements and Monte Carlo modelling determining americium deposited in the bone of a USTUR leg phantom. Preliminary results and conclusions of this intercomparison exercise are presented here.

[Novelties in the field of progression factors in chronic kidney disease]

The fight against chronic kidney disease is one of the most relevant aspects of nephrological practice, from both the perspective of clinical activity and research within the field of nephrology. In this brief article, we present in very summarized form some of the aspects in this field in the last year that the authors found of interest. Because the content of the next few pages was necessarily chosen on the basis of the authors' preferences, we assume that many other topics of great interest have been left out of this summary. In any case, we hope that this article will be interesting and useful and also serve as an subject of debate in nephrology forums.

Incidence of Beijing genotype of Mycobacterium tuberculosis in Elche, Spain: A 13-year surveillance study

Binary file ES_Abstracts_Final_ECDC.txt matches

Monte Carlo based voxel phantoms for in vivo internal dosimetry

The purpose of this communication is to describe briefly the computer programs developed to generate the MCNP input file corresponding to any segmented tomographic data and its application to the calibration procedures for in vivo internal dosimetry. The method has been applied to the determination of 241Am in bone by measurement in skull and knee using MCNP voxel models of a real human head and knee based on the tomographic Voxelman and Arms Down phantoms developed by Zubal et al. at Yale University.

Assessment of the internal dose of 241Am in bone by in vivo measurements of activity deposited in knee

In case of chronic exposure or long time after an acute intake of (241)Am as a consequence of an incident, the assessment of internal dose might be realised by estimating the total activity content of this element in the skeleton. For this purpose, a new methodology has been developed at the Whole Body Counting Laboratory of CIEMAT. In vivo measurements of this bone-seeker radionuclide in the knee are performed using four low energy germanium detectors inside a shielded room. The sensitivity study of this technique resulted in a minimum detectable activity of 7 Bq, for a counting time of 1800 s. Extrapolation to the total activity in the bone has been carried out by taking into account that the bone content of the knee calibration phantom is equivalent to 10.7% of the whole skeleton mass. The results of in vivo measurements of population and the procedure for internal dose evaluation are presented here.

[Update on gamma-hydroxybutyric acid]

AIMS

The article offers an updated review of the main pharmacological aspects of gamma-hydroxybutyric acid (GHB), as well as its clinical and behavioural effects.

DEVELOPMENT

A number of pharmacological, neurochemical and electrophysiological studies have clearly shown that endogenous GHB plays a role as a neurotransmitter and/or neuromodulator in the central nervous system (CNS). GHB displays specific synthesis, release and reuptake mechanisms, as well as particular binding sites that suggest the existence of a central GHBergic system. This substance, popularly known as 'liquid ecstasy', is also a potentially abusable drug; if administered for prolonged periods of time it can lead to dependence and withdrawal symptoms after the patient stops taking it. Its chief behavioural actions include sedation/sleepiness, induction of absence seizures, catalepsy or reduced aggression, among others. Some of these effects appear to be related to an interaction that has been reported to exist between the GHBergic system and the dopaminergic and GABAergic receptors in the CNS. From the clinical point of view, its use has been approved in some countries to treat the narcoleptic syndrome, and it has also been considered for possible use in the treatment of alcohol or opiate abuse. Finally, recent studies conducted with laboratory animals suggest the existence of a possible neurotoxic effect following prolonged administration in abusable dosages.

CONCLUSIONS

GHB is an extraordinarily interesting compound. It acts as a neurotransmitter/neuromodulator in the CNS. It is also an abusable recreational drug and may also be used to treat a number of different pathological conditions, the most important of which is narcolepsy. The possible development of neurotoxicity following prolonged administration, however, imposes considerable limitations on its usefulness in clinical contexts.

Effects of (+)SKF 10047, a sigma-1 selective agonist, on isolation-induced aggression in male mice

sigma-1 Receptors have been identified in numerous brain regions, including areas such as hypothalamus and amygdala, which have long been linked to the regulation of aggression. However, there is no clear information with respect to the possible effects of sigma-1 ligands on aggressive behavior in laboratory animals. Consequently, the present study examined the effects of (+)SKF 10047 (0.5-6 mg/kg, i.p.), a sigma-1 prototypical agonist, on isolation-induced aggression in male mice, using an ethopharmacological approach. Individually housed mice were exposed to anosmic "standard opponents" 30 min after drug administration. Ten minutes of diadic interactions were staged between a singly housed and an anosmic mouse in a neutral area. The encounters were videotaped, and the accumulated time allocated by subjects to 10 broad behavioral categories was estimated using an ethologically based analysis. Results showed that (+)SKF 10047 (6 mg/kg) produced a significant reduction of offensive behaviors, without affecting immobility. Social investigation behaviors were also slightly increased after drug treatment (2-6 mg/kg). These results suggest a role for sigma-1 receptors in aggression modulation in mice.

Behavioral profile of SB 269970, a selective 5-HT(7) serotonin receptor antagonist, in social encounters between male mice

The 5-HT(7) receptor is targeted by several antipsychotics, such as pimozide or clozapine, which have demonstrated antiaggressive properties in laboratory animal models. Likewise, 'in situ' hybridization and autoradiography studies have revealed moderate to high densities of 5-HT(7) receptors in limbic areas and hypothalamus, which have long been involved in the control of aggression. However, to date there is no evidence concerning the role of this receptor in the regulation of aggression. This study was designed to examine the effects of SB 269970 (1, 2, 4, 8, 16 and 32 mg/kg, i.p.), a selective 5-HT(7) receptor antagonist, on agonistic behavior elicited by isolation in mice. Individually housed mice were exposed to anosmic standard opponents 15 min after drug administration and encounters were videotaped and evaluated using an ethopharmacologically-based analysis. The results indicated that SB 269970 did not produce any significant behavioral changes, suggesting that 5-HT(7) receptors might not be involved in the modulation of aggression. Further studies with other selective ligands for these receptors are needed to confirm these findings.

Effect of clinical and socio-economic factors on the rate of clustering of Mycobacterium tuberculosis clinical isolates in Elche (Spain)

We studied the association that exists between the epidemiological type clustering of isolates of Mycobacterium tuberculosis and certain clinical, epidemiological and socio-economic characteristics of tuberculosis patients in the Elche health district of Spain. A total of 144 patients diagnosed between 1993 and 1999 and whose isolates had been genotyped by IS6110-RFLP in an earlier study were included. Multivariate analysis showed that the independent variables associated with clustering of strain types were: age (1-25 years, OR 2.92, 95% CI 0.83 10.3), a high percentage of infection in the first circle of contacts (OR 2.89, 95% CI 0.96-8.68), urban dwelling (OR 2.12. 95% CI 0.73-6.2), use of bronchoscopy to obtain samples (OR 16.3, 95% CI 2.3-11.5) and working contact with many people (OR 2.81, 95% CI 0.94-8.3). These data contribute to a better understanding of the epidemiology of tuberculosis and improved systems of control.

Effects of L-741,741, a selective dopamine receptor antagonist, on anxiety tested in the elevated plus-maze in mice

Dopamine systems are involved in modulation of anxiety. Although the action of D1/5, D2 and D3 receptor antagonists on anxiety has been documented in different animal models, little is known about the influence of D4 dopamine antagonists. The aim of this study was to examine the effects of L-741,741 (0.75, 1.5 and 3 mg/kg i.p.), a selective D4 dopamine receptor antagonist, on anxiety tested in the elevated plus-maze. Forty-eight albino adult male mice of the OF.1 strain were used. Animals were randomly allocated to one control group receiving physiological saline and dymethyl-sulphoxide (DMSO) (10%) and three experimental groups receiving L-741,741 injections. Tests were performed 30 min after injections for a duration of 5 min. A number of classical parameters were collected: i) open arm duration; ii) closed arm duration; iii) central platform duration; iv) open arm frequency; v) closed arm frequency; vi) central platform frequency; and vii) number of rearings. L-741,741 did not produce any significant behavioral changes under present test conditions, suggesting that the dopamine D4 receptor might not be involved in the modulation of anxiety-related behaviors in the plus-maze.

Androgen therapy for anemia in elderly uremic patients

Androgens were the mainstay of treatment of renal anemia prior to the introduction of recombinant human erythropoietin. With the introduction of this recombinant hormone, the protocols of treatment of anemia were completely modified, and the use of androgens was relegated to the background. However, several authors have continued showing interest in the use of androgenic steroids for the treatment of anemia. This review examines several aspects of aging on androgenic hormones and hematopoiesis, the effects of androgen administration on hematological parameters, the side effects of these compounds and the future of this treatment for anemia in renal patients.

Molecular epidemiology of tuberculosis in Elche, Spain: a 7-year study

The epidemiology of tuberculosis in Elche (Spain) was studied by restriction fragment-length polymorphism (RFLP) typing of clinical isolates of Mycobacterium tuberculosis over a 7-year period. A total of 165 isolates was typed and the clinico-epidemiological data of the patients were studied retrospectively. An overall cluster aggregation of 52.4% was found, rising to 71.43% in HIV-positive patients. There was greater aggregation in younger patients, but no statistically significant differences when other variables were analysed. The percentage of aggregation was higher than in other studies in Spain and this may be due to the longer time period of this study. The high percentage of aggregation in young patients and in thosewho were HIV-positive suggests increased recent transmission in both groups.

Attitudes toward animal research among psychology students in Spain

Animal research plays a central role in psychology, and its use, prevalence and quality depends on the attitudes of students who enter psychology in Spain. Attitudes among psychology students about the use of laboratory animals are not known, so the aim of this work was to analyze the attitudes of Spanish psychology students toward animal research. An attitude questionnaire of 15 items was given to 661 undergraduate students of the School of Psychology at the University of Málaga, Spain. Several results were found: (a) 65.7% of the respondents strongly agreed or agreed with animal research. General support for animal research was significantly higher by men than by women. (b) Support for animal research was higher for senior students, suggesting that the psychology curriculum or self-selection to remain in the program might influence students' attitudes. (c) Attitudes toward animal research were similar among students independent of the type of animal being used for research in biological or psychological studies. (d) 58% considered that laboratory animals never or almost never are inappropriately handled. (c) 55.6% indicated that research in psychology on animals could be generalized to humans. Overall, these results suggest that among Spanish psychology students animals research is considered important for the advancement of the science. Likewise, a majority of students displayed positive attitudes toward animal research.

MDMA ("ecstasy") exhibits an anxiogenic-like activity in social encounters between male mice

Recent studies have suggested that 3,4-methylenedioxymethamphetamine (MDMA; "ecstasy"), a synthetic amphetamine derivative, might exhibit an anxiogenic-like activity in rodents. In this work, we examined the effects of MDMA (1, 8 and 15 mg kg(-1), i.p.) on social encounters between male mice using an ethopharmacological approach. Likewise, we compared the behavioural profile of MDMA with that induced by FG 7142 (15 mg kg(-1), i.p.), an anxiogenic benzodiazepine receptor ligand. Individually housed mice were exposed to anosmic standard opponents 30 min after drug administration, and the encounters were videotaped and evaluated using an ethologically based analysis. MDMA (8 and 15 mg kg(-1)) produced a behavioural pattern characterized by a marked decrease of aggression (threat and attack) as well as social investigation, body care and digging behaviours, without affecting immobility. Moreover, avoidance/flee and defence/submission behaviours were significantly increased by the drug. A very similar behavioural profile was observed in FG 7142-treated animals. Overall, these findings might indicate that MDMA has anxiogenic-like properties in male mice.

In-depth review effect of androgens on anemia and malnutrition in renal failure: implications for patients on peritoneal dialysis

OBJECTIVE

To analyze the implications of the potential use of androgens in peritoneal dialysis patients, focusing on their effects on hematologic and nutritional parameters. This manuscript reviews the different compounds for clinical use, dosage schedules, adverse effects, and how therapy with androgens might be used to treat anemia and malnutrition in these dialysis patients.

DATA SOURCES

Studies in the literature dealing with the effects of androgens on hematologic and nutritional parameters, and their role in uremic anemia and malnutrition.

STUDY SELECTION

Studies in which uremic patients received androgens as therapy for anemia or malnutrition.

DATA EXTRACTION

Data were abstracted from all of these studies.

RESULTS

This review shows that androgens are anabolic substances that also have significant actions on erythropoiesis. A number of clinical studies in uremic patients have found that these compounds have beneficial effects on hematologic parameters and nutritional status, similarly to other therapies, such as recombinant human erythropoietin and recombinant human growth hormone, respectively.

CONCLUSIONS

Androgens have been shown to have a beneficial effect on anemia due to renal disease and on nutritional status in uremic patients. Further studies need to be done with larger groups of patients. Objectives for additional research are suggested.

Intradialytic cardiovascular stability with low calcium dialysate levels

Over the last few years, the use of calcium salts has become an alternative method to phosphate binders containing aluminum in the control of hyperphosphatemia in dialysis patients, hypercalcemia being the main limitation to this therapeutical approach [1]. On this basis, a reduction in the calcium dialysate (CD) concentration has been proposed in order to prevent the appearance of hypercalcemia [2, 3]. However, the use of low CD concentrations may have negative effects on cardiovascular stability during hemodialysis (HD) [4, 5].

Effects of 3,4-methylenedioxy-methamphetamine (MDMA) on anxiety in mice tested in the light-dark box

1. The effects of acute administration of 3,4-methylenedioxymethamphetamine (MDMA; "ecstasy") on anxiety tested in the light/dark box were examined in albino male mice of the OF.1 strain. 2. Animals were evaluated in the light/dark test 30 min after injection of MDMA (1, 8, and 15 mg/kg, i.p) or saline. The following parameters were recorded (for 5 min); (a) number of exploratory rearings in the light and dark sections; (b) number of transitions between the lit and dark areas; (c) time spent in the light and dark areas; (d) latency of the initial movement from the light to the dark area, and (e) locomotor activity in light area. 3. MDMA (8 and 15 mg/kg) produced a significant reduction in exploratory activity (rearings and transitions), without decreasing motility, in comparison with saline-treated mice. However, time spent in lit/dark compartments was not significantly affected by the drug, which could be a consequence of the anti-exploratory properties of MDMA. 4. Overall, the behavioral profile found in the light/dark test indicates an anxiogenic-like activity of MDMA in mice. It is suggested, however, that animal models of anxiety which emphasize a social interaction could be more sensitive to the effects of this substance.

Amino acid losses during hemodialysis with polyacrylonitrile membranes: effect of intradialytic amino acid supplementation on plasma amino acid concentrations and nutritional variables in nondiabetic patients

BACKGROUND

Malnutrition is highly prevalent in hemodialysis patients. Amino acid (AA) losses during the dialysis procedure may be a contributing factor.

OBJECTIVES

The objectives of this study were 1) to prospectively evaluate AA losses and their effect on plasma AA concentrations during dialysis with polyacrylonitrile at baseline and after administration of AAs by intradialysis and 2) to investigate the effects of intradialytic AA supplementation on nutritional status.

DESIGN

Seventeen stable patients without diabetes who were receiving hemodialysis were studied. In the first phase, AA losses were evaluated over 2 wk in 10 patients randomly assigned to receive AA supplementation. AA losses were analyzed during the first week without supplementation and during the second week with AA administration. In the second phase, the patients' nutritional status was investigated after 3 mo of AA supplementation and was compared with those in 7 patients not receiving AAs.

RESULTS

Mean +/- SD) AA losses during a 4-h dialysis session were 12 +/- 2 g; there was a significant decrease in plasma AA concentrations (386 +/- 298 micromol/L for essential and 902 +/- 735 micromol/L for nonessential AAs). After administration of AAs, the losses increased to 28 +/- 4 g. However, this procedure produced a positive net balance of AAs (10.6 +/- 5.6 g for total AAs), preventing a reduction in plasma concentrations. After 3 mo of AA administration, there was a significant increase in protein catabolic rate and serum albumin and transferrin. This improvement occurred without any change in the dialysis dose, ruling out the possibility that an increase in dialysis efficiency played a role.

CONCLUSIONS

Intradialysis adequately provides AA supplements, prevents reductions in plasma AA concentrations, and favorably affects the nutritional status of patients receiving hemodialysis.