[Epidemiological characteristics of out-of-hospital cardiorespiratory arrest recorded by the 061 emergencies system (SAMU) in the Balearic Islands (Spain), 2009-2012]. / Características epidemiológicas de las paradas cardiorrespiratorias extrahospitalarias registradas por el sistema de emergencias 061 (SAMU) de la Comunidad Autónoma de las Islas Baleares (2009-2012).

OBJECTIVE: To describe the epidemiology of out-of-hospital cardiorespiratory arrest (OHCA) and identify factors associated with recovery of spontaneous circulation (ROSC). DESIGN: Observational study of OHCA registered on a continuous basis in the Emergency Medical Services (EMS) database during 2009-2012. SETTING: The islands of Mallorca, Ibiza, Menorca and Formentera (Balearic Islands, Spain). PATIENTS: OHCA in patients ≥ 18 years of age. The main variables were: Patient sex, age, probable cause, place of arrest, bystander, witnessed, basic life support (BLS), shockable rhythm, intervention time, semi-automatic defibrillator (AED), duration of cardiopulmonary arrest (CA), and ROSC. Independent variables were defined according to the Utstein protocol, and the dependent variable was defined as ROSC. RESULTS: The EMS treated 1170 OHCAs (28/100,000 persons-year). We included 1130 CA. The mean age was 61.4 years (73.4% males). Most CA (72.3%) were of cardiac etiology, and 84.7% were witnessed. A total of 840 (74.3%) received BLS and 400 (47.6%) did so before arrival of the EMS (45 by bystander relatives). AED was available in 330 cases CA (29.2%) (96 with shockable rhythm). The interval between emergency call and BLS and between emergency call and advanced life support was 8.4 and 15.8min, respectively. Shockable rhythm was monitored in 257 CAs (22.7%). ROSC occurred in 261 (23.1%). Factors associated with ROSC were age, shockable rhythm, BLS before EMS arrival, and CA duration less than 30min. CONCLUSION: The incidence rate of the OHCA is low. The proportion of patients receiving BLS from relatives was low. Age, shockable rhythm and BSL before EMS arrival were associated with ROSC.

Serum soluble interleukin 2 receptor (sIL-2R) as a marker of acute rejection in renal transplant children.

The aim of the study was to evaluate whether or not serum levels of soluble interleukin 2 receptor (sIL-2R) predict acute rejection in pediatric recipients. We studied 51 pediatric renal transplant recipients divided into three groups: Group 1) Biopsy-proven cellular acute rejection (n = 19), Group 2) Graft dysfunction with histological diagnosis other than acute rejection (n = 8) and Group 3) Patients with stable graft function, no biopsy (n = 24). Serum samples for sIL-2R measurement by sandwich ELISA were obtained at the time of renal transplant and at the time of renal biopsy due to graft dysfunction (Groups 1 and 2) or at six months post-transplant in the case of Group 3. The mean ± s.e. serum values of sIL-2R were higher in patients during acute rejection (6539 ± 1802 pg/mL) compared to patients with other causes of graft dysfunction (2217 ± 256 pg/mL) or stable graft function at six months (2183 ± 283 pg/mL) (Kruskal-Wallis p = 0.004). When the sIL2-R levels at the time of transplant were compared to those at the time of biopsy (Groups 1 and 2) or at six months post-transplant in Group 3, there was no significant difference between baseline and biopsy in the acute rejection group (paired t-test = 0.07), whereas there was a significant reduction in Groups 2 and 3.

Efficacy and safety of conversion of mycophenolate mofetil to enteric-coated mycophenolate sodium in Mexican renal transplant children.

The aim of the study was to evaluate the efficacy and safety of the conversion of MMF to EC-MPS in pediatric renal transplant recipients. We included 12 patients with stable graft function who were receiving MMF treatment. In the first visit, a complete medical examination was performed, which included a GSRS, a nine-point pharmacokinetic profile, samples for renal, liver and hematological tests and evaluation of IMPDH2 gene expression. The patients were transferred to an equimolar dose of EC-MPS. Two wk later, a clinical evaluation and blood collection, as in the first visit were performed. There was no change in serum creatinine, leukocyte count, serum albumin, or transaminase levels, but we found a statistically significant reduction of hemoglobin after conversion (13.2 +/- 1.6 g/dL with MMF vs. 12.5 +/- 1.3 g/dL when receiving EC-MPS). The GSRS total mean score was 16 +/- 12 with MMF vs. 8 +/- 5 with EC-MPA (p < 0.05). There was no statistically significant difference between formulations in the gene expression of IMPDH 2, in the AUC(0-12h) or in C(max). However, peak concentration occurred later with EC-MPS.

Artificial intelligence to predict clinical disability in patients with multiple sclerosis using FLAIR MRI.

PURPOSE: The purpose of this study was to create an algorithm that combines multiple machine-learning techniques to predict the expanded disability status scale (EDSS) score of patients with multiple sclerosis at two years solely based on age, sex and fluid attenuated inversion recovery (FLAIR) MRI data. MATERIALS AND METHODS: Our algorithm combined several complementary predictors: a pure deep learning predictor based on a convolutional neural network (CNN) that learns from the images, as well as classical machine-learning predictors based on random forest regressors and manifold learning trained using the location of lesion load with respect to white matter tracts. The aggregation of the predictors was done through a weighted average taking into account prediction errors for different EDSS ranges. The training dataset consisted of 971 multiple sclerosis patients from the "Observatoire français de la sclérose en plaques" (OFSEP) cohort with initial FLAIR MRI and corresponding EDSS score at two years. A test dataset (475 subjects) was provided without an EDSS score. Ten percent of the training dataset was used for validation. RESULTS: Our algorithm predicted EDSS score in patients with multiple sclerosis and achieved a MSE=2.2 with the validation dataset and a MSE=3 (mean EDSS error=1.7) with the test dataset. CONCLUSION: Our method predicts two-year clinical disability in patients with multiple sclerosis with a mean EDSS score error of 1.7, using FLAIR sequence and basic patient demographics. This supports the use of our model to predict EDSS score progression. These promising results should be further validated on an external validation cohort.

The impact of the invasive species Vespa velutina on honeybees: A new approach based on oxidative stress.

Honeybees have an essential role in ecosystems pollinating wild flowers and cultivated crops, representing an important cultural and economic benefit for humans. Honeybee populations are decreasing over the last decade, due to multifactorial causes. The aim of this field study was to investigate the effects of the presence of the invasive species Vespa velutina, a bee predator, in oxidative stress parameters of honeybee workers. To achieve this objective, positive or negative apiaries for the presence of the V. velutina were selected. Five honeybees from six hives of each apiary were sampled in spring, summer and autumn, analysing a total of 233 samples. Analysis of mRNA expression of oxidative stress-related genes, catalase enzymatic activity and lipid peroxidation were performed. An increase in sod2, tpx3, trxR1, gtpx1, gstS1, coxI, cytC and if2mt genes expression, as well as a raise in catalase activity and lipid peroxidation were observed in V. velutina positive samples. Thus, here we present a new methodology to analyze the impact of the predation pressure of the invasive species V. velutina on honeybees under field conditions. In conclusion, the results obtained in this study indicate the negative impact of the presence of the yellow-legged hornet on honeybees' health and the activation of their antioxidant system to protect them against this biotic stressor. Moreover, the redox status they present could increase the susceptibility of honeybees, essential insects that currently receive many inputs of different stresses, to another stressor.

[Concordances between autism spectrum disorders and attention deficit hyperactivity disorder]. / Concordancias entre los trastornos del espectro del autismo y el trastorno por deficit de atencion/hiperactividad.

INTRODUCTION: The current literature acknowledges an overlap of genetic, clinical and neuropsychological aspects between autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD), suggesting that there may be a common pattern that covers features ranging from the common genetic and structural aetiology to shared patterns of symptoms. AIM: To review the current advances in these common aspects. DEVELOPMENT: Several studies have pointed out preschool attentional difficulties as the basis of both disorders. From the genetic perspective, it is estimated that 50-72% of the genetic factors overlap between the two disorders. They also share a decrease in the volume of the corpus callosum and left frontal grey matter, as well as functional alterations such as dorsolateral prefrontal, striato-thalamic and superior parietal hypoactivation. Results are also found regarding executive functioning, with differential profiles for the two conditions, and also concerning the relationship between the repetitive and impulsive behaviours in the early stages of ASD and ensuing problems of hyperactivity. CONCLUSIONS: This new conception of the ASD-ADHD continuum, with a common neurodevelopmental basis and associated clinical features, could be of great use in clinical practice. It is suggested that this association should be taken into account when it comes to deciding on the treatment.

TITLE: Concordancias entre los trastornos del espectro del autismo y el trastorno por deficit de atencion/hiperactividad.Introduccion. La bibliografia actual reconoce un solapamiento de aspectos geneticos, clinicos y neuropsicologicos entre el trastorno del espectro del autismo (TEA) y el trastorno por deficit de atencion/hiperactividad (TDAH), sugiriendo que podria existir un patron comun que abarca desde la etiologia genetica y estructural comun hasta patrones sintomatologicos compartidos. Objetivo. Revisar los avances actuales en estos aspectos comunes. Desarrollo. Se han encontrado trabajos que apuntan a dificultades atencionales preescolares en la base de ambos trastornos. Desde la perspectiva genetica, se estima que un 50-72% de factores geneticos se solapan entre ambos trastornos. Tambien comparten una disminucion del volumen del cuerpo calloso y la sustancia gris frontal izquierda, y alteraciones funcionales como la hipoactivacion prefrontal dorsolateral, estriadotalamica y parietal superior. Se encuentran resultados en cuanto al funcionamiento ejecutivo, con perfiles diferenciales para ambas condiciones, y tambien sobre la relacion de los comportamientos repetitivos e impulsivos en las primeras etapas en TEA, con los problemas hiperactivos posteriores. Conclusiones. Esta nueva concepcion del continuo TEA-TDAH, con una base neuroevolutiva comun y caracteristicas clinicas asociadas, podria ser de gran utilidad para la practica clinica y se sugiere considerar la asociacion a la hora de plantear el tratamiento.

[Randomised controlled study of inter-hemispheric electroencephalographic coherence following assisted therapy with dolphins in children with autism spectrum disorders]. / Estudio aleatorizado controlado de la coherencia interhemisferica del electroencefalograma tras terapia asistida con delfines en niños con trastorno del espectro autista.

INTRODUCTION: Autism spectrum disorder (ASD) is a neurodevelopmental disorder associated with impairments in executive function, language, emotional function, and social function. Its anatomofunctional substrate is related to a disorganization of the brain's functional connections. The aim is to investigate the cerebral connections in subjects with ASD through the analysis of the interhemispheric coherence (IHC) of the quantified electroencephalogram and its changes after dolphin assisted therapy (DAT) versus therapeutical intervention without dolphins (TIWD). PATIENTS AND METHODS: The IHC was determined in 44 subjects with ASD before randomly assigning them to two therapeutic groups: DAT (n = 22) and TIWD (n = 22). The results were statistically analyzed through the multi-measure ANOVA test for within-subject (time) and between-subject (DAT vs TIWD) factors. RESULTS: The IHC showed a significant reduction (p < 0.05) for both groups in the delta, theta, beta, and alpha frequencies (p < 0.001) in the anterior frontal region (F3-F4), alpha in the central region (C3-C4) (p < 0.05), and alpha (p < 0.05) and beta (p < 0.001) in the temporal region (T3-T4). In the intersection with the specific treatment (DAT), the coherence in the alpha band increased in Fp1-Fp2 (p < 0.05), and the delta did not decline in F3-F4 (p < 0.05). CONCLUSION: In 5-year-old children with ASD, DAT increases the IHC in the anterior frontal region and stabilizes the tendency to reduce the delta band in the posterior frontal region.

TITLE: Estudio aleatorizado controlado de la coherencia interhemisferica del electroencefalograma tras terapia asistida con delfines en niños con trastorno del espectro autista.Introduccion. El trastorno del espectro autista (TEA) es un trastorno del neurodesarrollo asociado con trastornos de la funcion ejecutiva, el lenguaje, la funcion emocional y la funcion social, cuyo sustrato anatomofuncional se relaciona con una desorganizacion de las conexiones funcionales cerebrales. El objetivo es investigar las conexiones cerebrales en sujetos con TEA mediante analisis de la coherencia interhemisferica (CIH) del electroencefalograma cuantificado y sus cambios tras la terapia asistida con delfines (TAD) frente a la intervencion terapeutica sin delfines (ITSD). Pacientes y metodos. Se determino la CIH en 44 sujetos con TEA antes de asignarse aleatoriamente a dos grupos de tratamiento: TAD (n = 22) e ITSD (n = 22). Los resultados se analizaron estadisticamente mediante el test de la ANOVA multimedida para los factores intrasujeto (tiempo) e intersujeto (TAD frente a ITSD). Resultados. La CIH mostro una reduccion significativa (p < 0,05) para ambos grupos en las frecuencias delta, theta, beta y alfa (p < 0,001) en la region frontal anterior (F3-F4). Se hallo tambien una reduccion en la frecuencia alfa en la region central (C3-C4) (p < 0,05), y alfa (p < 0,05) y beta (p < 0,001) en la region temporal (T3-T4). En la interseccion con el tratamiento especifico (TAD), la coherencia en la banda alfa aumento en Fp1-Fp2 (p < 0,05) y no descendio la delta en F3-F4 (p < 0,05). Conclusion. En niños de 5 años con TEA, la TAD aumenta la CIH en la region frontal anterior y estabiliza la tendencia a la reduccion de la banda delta en la region frontal posterior.

Perioperative functional neuroimaging of gliomas in eloquent brain areas.

Surgical resection of gliomas involving eloquent brain areas must be maximal in order to improve patients' survival, and safe to prevent postoperative impairments. Therefore, the precise spatial relationship between the lesion and eloquent brain areas needs to be established. Functional magnetic resonance imaging and diffusion tensor imaging are robust methods with increasing indications in neurosurgery for past decade. The aim of this review article is not only to pinpoint the major limitations of these methods in order to avoid erroneous conclusions, but also to detail practical aspects associated with the main paradigms routinely used in functional magnetic resonance imaging, and to discuss recent validation of functional magnetic resonance imaging and diffusion tensor imaging results with direct electrical stimulation during awake surgery.

Design, construction, and performance of a device for directional recrystallization of metallic alloys.

A device was designed to apply the directional recrystallization method to Fe-based alloys in order to obtain bamboo-like microstructures. This microstructure is suitable for improving creep properties and resistance to fatigue in some alloys and for enhancing pseudoelastic properties in shape memory alloys. The design and construction of a flat coil are described in detail. In addition, we developed an electromechanical system to control the movement of a wire within the flat coil. The construction details and system performance are presented. Furthermore, metallographic studies taken from the directionally recrystallized low-carbon steel samples are shown. Nearly monocrystalline and bamboo-like microstructures were achieved in the steel wires.

Sex steroid receptor expression in different adipose depots is modified during midpregnancy.

Sex hormone signalling is key in the understanding of adipose tissue metabolism during pregnancy. Sex hormones play an important role in adipose tissue metabolism by activating specific receptors that alter several steps of lipolysis and lipogenesis. We analyze steroid receptor mRNA levels in different rat adipose depots and mammary fat pad, as well as the sex hormone profile during midpregnancy, coinciding with the placentation process. Thus, progesterone and estradiol plasma levels were increased as well as testosterone levels. This hormonal profile was accompanied by low glucose to insulin ratio. PR-B, ERalpha and AR receptor densities during midpregnancy were dependent on adipose depot location. In mammary fat pad, the mRNA levels of sex hormone receptors were correlated with the growth of the depot. These results demonstrate that sex steroid hormone receptor mRNA expression during midpregnancy is tissue-specific. Our results agree with the idea that the increased estrogenic and androgenic signalling could be addressed to reducing the lipogenic state in early pregnancy exerted mainly by progesterone and to prepare adipose tissue for the beginning of the catabolic phase in late pregnancy in a depot-specific manner.

CYP3A5 Genotype and Time to Reach Tacrolimus Therapeutic Levels in Renal Transplant Children.

BACKGROUND: CYP3A5 gene polymorphism rs776746 has been associated with lower tacrolimus dose requirements and bioavailability in both adults and children. This variant causes a loss of CYP3A5 activity owing to a splice site variant leading to a truncated inactive enzyme. The aim of this study was to determine if the rs776746 gene polymorphism is related to the time to reach tacrolimus therapeutic levels in renal transplant children. METHODS: A prospective study was performed in renal transplant children receiving tacrolimus as part of their immunosuppressive regime. CYP3A5 genotype was determined by direct sequencing. Tacrolimus trough levels and serum creatinine at 1 week and 1 month after renal transplantation was obtained from clinical chart. RESULTS: A total of 42 patients were included; 19 (45.2%) were female, 23 (54.8%) received living-donor transplants, and 21 patients expressed CYP3A5*1/*1 or CYP3A5*1/*3. Tacrolimus dose was higher in expressers at week 1 (0.13 vs 0.10 mg/kg/d; P = .011), and week 4 after transplantation (0.17 vs 0.09 mg/kg/d; P < .0001). At 4 weeks after renal transplantation, only 9 patients from the expressers group (42.8%) had levels ≥7 ng/mL, in contrast to 18 in the nonexpressers group (85.7%; Fisher exact P = .008). CONCLUSIONS: Tacrolimus dose was significant higher in functional CYP3A5 expressers. Only 42.8% of such expressers had tacrolimus trough levels ≥7 ng/mL at 1 month after transplantation despite dose adjustments. Long-term follow up is needed to address the consequences of early post-transplantation bioavailability differences due to CYP3A5 genotype.

Spatial normalization of brain images and beyond.

The deformable atlas paradigm has been at the core of computational anatomy during the last two decades. Spatial normalization is the variant endowing the atlas with a coordinate system used for voxel-based aggregation of images across subjects and studies. This framework has largely contributed to the success of brain mapping. Brain spatial normalization, however, is still ill-posed because of the complexity of the human brain architecture and the lack of architectural landmarks in standard morphological MRI. Multi-atlas strategies have been developed during the last decade to overcome some difficulties in the context of segmentation. A new generation of registration algorithms embedding architectural features inferred for instance from diffusion or functional MRI is on the verge to improve the architectural value of spatial normalization. A better understanding of the architectural meaning of the cortical folding pattern will lead to use some sulci as complementary constraints. Improving the architectural compliance of spatial normalization may impose to relax the diffeomorphic constraint usually underlying atlas warping. A two-level strategy could be designed: in each region, a dictionary of templates of incompatible folding patterns would be collected and matched in a way or another using rare architectural information, while individual subjects would be aligned using diffeomorphisms to the closest template. Manifold learning could help to aggregate subjects according to their morphology. Connectivity-based strategies could emerge as an alternative to deformation-based alignment leading to match the connectomes of the subjects rather than images.

Fast contrast-enhanced 4D MRA and 4D flow MRI using constrained reconstruction (HYPRFlow): potential applications for brain arteriovenous malformations.

BACKGROUND AND PURPOSE: HYPRFlow is a novel imaging strategy that provides fast, high-resolution contrast-enhanced time-resolved images and measurement of the velocity of the entire cerebrovascular system. Our hypothesis was that the images obtained with this strategy are of adequate diagnostic image quality to delineate the major components of AVMs. MATERIALS AND METHODS: HYPRFlow and 3D TOF scans were obtained in 21 patients with AVMs with correlative DSA examinations in 14 patients. The examinations were scored for image quality and graded by using the Spetzler-Martin criteria. Mean arterial transit time and overlap integrals were calculated from the dynamic image data. Volume flow rates in normal arteries and AVM feeding arteries were measured from the phase contrast data. RESULTS: HYPRFlow was equivalent to 3D-TOF in delineating normal arterial anatomy, arterial feeders, and nidus size and was concordant with DSA for AVM grading and venous drainage in 13 of the 14 examinations. Mean arterial transit time on the AVM side was 0.49 seconds, and on the normal contralateral side, 2.53 seconds with P < .001. Across all 21 subjects, the mean arterial volume flow rate in the M1 segment ipsilateral to the AVM was 4.07 ± 3.04 mL/s; on the contralateral M1 segment, it was 2.09 ± 0.64 mL/s. The mean volume flow rate in the largest feeding artery to the AVM was 3.86 ± 2.74 mL/s. CONCLUSIONS: HYPRFlow provides an alternative approach to the MRA evaluation of AVMs, with the advantages of increased coverage, 0.75-second temporal resolution, 0.68-mm isotropic spatial resolution, and quantitative measurement of flow in 6 minutes.

Estrogen effects on blood amino acid compartmentation.

The present paper focuses on the study of blood amino acid compartmentation in healthy men (lean and obese) and women, with special emphasis on the estimation of the recently described blood-cell adsorbed amino acid pool. The wide range of changes found in this pool on comparing different physiological situations may be attributable to its proposed characteristic high dynamism on the one hand, but also to the influence of other factors such as hormones. Along these lines, the sex- and obesity-linked variations found here in human blood led to the speculation as to whether these differences could be related to the influence of estrogens. This hypothesis was further tested by chronically treating a group of male rats with estrone and checking their subsequent blood amino acid compartment changes (which yielded a greater difference in the adsorbed pool). From the overall results obtained it may be concluded that the higher production of estrogens in women and obese men affects amino acid availability to the tissues by modulating the blood-cell adsorbed amino acid pool through a mechanism that is, at present, unknown.

A simplified method for the estimation of individual amino acid radioactivity in plasma samples.

A method is presented for the quantitative estimation of the individual amino acid radioactivity in biological samples. The material is deproteinized with cold acetone, and, after acetone evaporation, is passed through a column containing 1 g of Amberlite XAD-2, then eluted with 10% ethanol. The samples are derivatized with Sanger's reagent (alkaline 1-fluoro-2,4-dinitrobenzene) and passed again through the Amberlite XAD-2 column; the 10% ethanol eluate is now discarded and the DNP-amino acids eluted with acetone. Aliquots are used for TLC chromatography on Silicagel plates; the spots are identified, cut away and their radioactivity estimated. The actual recovery of radioactivity in the spots is about 86-92% of the initial radioactivity. No contamination with radioactive glucose, lactate, pyruvate or glycerol has been observed.

An enzyme specific method for estimation of pyruvic acid radioactivity in biological samples.

A method for the estimation of pyruvate radioactivity in complex biological samples is presented. After perchloric acid deproteinization, the samples were divided in two aliquots. All pyruvate was removed from the first aliquot with lactate dehydrogenase and NADH; the other was left undisturbed. Then all hydrophilic components of the sample were removed through an Amberlite XAD-7 column. The samples were treated with dinitrophenylhydrazine to obtain the corresponding hydrazones, which were retained in an Amberlite XAD-7 column and then were eluted with acetone and their radioactivity counted. The difference between both aliquots corresponded to the pyruvate radioactivity in the sample. No contamination by lactate, glycerol, glucose or amino acids was observed. The mean recovery of 5 determinations of pyruvate radioactivity was 91.3% +/- 1.0.

Enzymatic determination of carbon (14C)-labeled glycerol in biological samples.

A method for determination of glycerol-specific-radioactivity in biological samples is presented. It is based on the following steps: (a) enzymatic conversion of glycerol to dihydroxyacetone-phosphate, (b) quantitative trapping of dihydroxyacetone-phosphate in SPE amino (NH2) columns, (c) eluation with HCl 0.5 N of dihydroxyacetone-phosphate followed by radioactivity counting and (d) estimation of the radioactivity thus trapped compared with that of enzymatically untreated aliquots of the same samples. No interferences from other 14C-labeled materials tested such as D-glucose, L-alanine, L-glutamine and D-beta-hydroxybutyrate were observed. This inexpensive and high-speed method can be applied in routine multiple estimations of glycerol-specific-radioactivity in biological samples in tracer metabolic studies.

A method for the simultaneous determination of total carbohydrate and glycerol in biological samples with the anthrone reagent.

A method for quantitative estimation of glycerol and total carbohydrate in biological samples is described. The samples, deproteinized with cold acetone or trichloroacetic acid, were treated in the cold with 10 vols. of 0.75% (w/w) anthrone in 84% (w/w) sulphuric acid, and then heated 10 min at 100 degrees C. Absorbance at 590 nm was used for evaluation of total carbohydrate content in the sample. The absorbance at 510 nm was used for the combined carbohydrate and glycerol estimation. This latter observation leads to the determination of the glycerol content of the sample because the carbohydrate interference is known from the data obtained at 590 nm. Uses of this method to determine glycerol and carbohydrate content in lipids of chicken egg-yolk samples are presented.

On the relation between citrate and calcium in normal and stone-former subjects.

The aim of this work is to evaluate citrate in a group of patients with calcium oxalate urolithiasis and in a control group for detecting possible differences between the two groups. The mean urinary concentration in the stone-formers was found significantly lower than in the controls. Particularly interesting was the correlation study between citrate and calcium. It was found that patients with hypocitraturia have hypercalciuria. Thus, it is particularly interesting to point out the importance of citrate in preventing the risk of lithiasis in the group of stone-formers studied by us.

On the relation between citrate and calcium in normal and stone-former subjects.

The aim of this work is to evaluate citrate in a group of patients with calcium oxalate urolithiasis and in a control group for detecting possible differences between the two groups. The mean urinary concentration in groups of stone-formers was found significantly lower than in the control group. Particularly interesting was the correlation study between citrate and calcium. It was found that patients with hypocitraturia have hypercalciuria. Thus, it is particularly interesting to point out the importance of citrate in preventing the risk of lithiasis in stone-formers studied by us.