Quantification of Major Inorganic Contaminants in a Mediterranean Coastal Lagoon with a Large Dystrophic Crisis.

In August 2021, the Mar Menor, a saltwater lagoon located in the Region of Murcia (Spain), suffered a tragic environmental episode of dystrophic crisis and anoxia. The appearance of numerous dead fish in different areas of the lagoon over the course of days put all the authorities and the population of the area on alert. This paper shows a case study of what happened in the lagoon in terms of the presence of the most common inorganic pollutants. Measurements of the concentration of nitrogen species, phosphates and main heavy metals were carried out at different sampling sites in the Mar Menor from May 2021 to November 2022. Chemical analyses were carried out for each of the species under study. These analyses provide valuable information about the dystrophic crisis caused by a classic eutrophication process that began with the excessive nutrient input into the Mar Menor. Ion chromatography and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) were used as instrumentation for the quantification of these samples. The species whose values were greatly increased after the tragic episode described above were nitrates. The concentration varied significantly at the different sampling sites throughout the study. On the last sampling date, decreased concentrations of all the species were measured at each of the sampling sites, coinciding with the apparent good state of the lagoon.

Complete and simultaneous removal of ionic silver and silver nanoparticles by using an ionic liquid supported on a magnetic nanoparticle core.

The global pandemic situation due to COVID-19 has given rise to the massive use of disinfectant products, many of them based on silver atoms. After the use of these products, the silver passes into the aqueous effluents, becoming an emerging contaminant in waters. In this work, a novel procedure for the total and simultaneous removal of ionic and nanomeric silver in aqueous samples is introduced, employing magnetic nanoparticles wrapped with an ionic liquid (Fe3O4@IL) as a removal agent. Experimental variables such as pH, contact time, temperature, as well as pollutant and removal agent doses were studied to achieve the total elimination, exhibiting exceptional conditions for the removal of different concentrations of silvers species in water. The approach achieves 100% removal efficiency for the simultaneous removal of both silver species, goal not achieved previously. Also, 100% removal efficiency is reached for the both species separately, since ionic silver is adsorbed onto the Fe3O4, while nanomeric silver is extracted in the IL. Particularly, for concentrations within the range 50-200 µg L-1, total removal efficiency was reached for a wide range of temperatures and a pH range 7-9, achieved in just 15 min, for all cases. Additionally, the doses of Fe3O4@IL employed to remove all concentrations of silver were 13.7 mg. Characterization of Fe3O4@IL surfaces before and after the process was performed by means of Field Effect Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy. Fe3O4@IL was recycled by employing 100 µL of 1% HNO3 solution, allowing its use for 10 additional silver removal cycles without loss of efficiency. The study of adsorption kinetics and equilibrium isotherms reveal a Freundlich-type adsorption, which suggests affinity between sites in the complex surface of Fe3O4@IL, and Elovich kinetics, indicative of chemisorption onto a heterogeneous surface, while the temperature shows no effect on the results.

Total removal of amoxicillin from water using magnetic core nanoparticles functionalized with silver.

Framed in the problem of emerging pollutants, in this work we introduce a novel procedure for the total removal of amoxicillin from water samples using magnetic nanoparticles functionalized with nanometric silver (Fe3O4@AgNPs). Experimental conditions such as pH, contact time, temperature, as well as adsorbate and adsorbent doses have been studied to achieve the total adsorption for different concentrations of amoxicillin in water. Particularly, for concentrations 10 and 100 mg L-1, a maximum removal efficiency of 100% was reached at room temperature and pH = 7 after 15 min of contact time between adsorbent and water samples under gentle shaking. The doses of adsorbent employed to remove 10 and 100 mg L-1 of amoxicillin were 100 and 500 µL, respectively. Characterization of the adsorbent surfaces was performed by Scanning and Transmission Electron Microscopy, Energy Dispersive X-ray Spectroscopy, BET analysis and Fourier-transform infrared spectroscopy. Recycling studies were carried out employing 500 µL of NaOH solution 1 M during 15 min in order to explore desorption and reuse of the adsorbent, showing that Fe3O4@AgNPs remains unaltered and can be used for two more additionally adsorption cycles, exhibiting 93% adsorption efficiency after the third regeneration. The characterization of equilibrium isotherms and thermodynamics reveal a Langmuir-type endothermic chemisorption.

Simultaneous adsorption of mercury species from aquatic environments using magnetic nanoparticles coated with nanomeric silver functionalized with l-Cysteine.

We introduce a novel, efficient and fast method for the total and simultaneous removal of monomethylmercury, dimethylmercury, ethylmercury and Hg (II) from aquatic environments using magnetic core nanoparticles, coated with metallic nanomeric silver and functionalized with l-Cysteine. As far as the authors know, simultaneous removal has not been achieved previously. The experimental design was based on exploring a wide range of experimental conditions, including pH of the medium (2-12), contact time (up to 20 min), adsorbent dose (50-800 µL) and temperature (293-323 K), in order to achieve the highest adsorption efficiency. The results show that, for a pH equal to 6.2 at room temperature, 400 µL of nanoparticles is sufficient to achieve 100% adsorption efficiency for all the studied Hg species after a contact time of 30 s. The adsorbent was characterized by means of Scanning Electron Microscopy, Energy Dispersive X-ray Analysis, Fourier-Transform Infrared Spectroscopy and a BET test. Moreover, the procedure allows the total recovery and recycling of the nanoparticles using 50 µL of 0.01 M KI. As regards reuse, the adsorbent exhibits no loss of adsorption capacity during the first three adsorption cycles. Thermodynamics reveals that adsorption is of a physicochemical nature, the equilibrium isotherms being described by a Langmuir model for all the Hg species. The ability of the method to simultaneously adsorb all species of mercury present in water, achieving full adsorption in just a few seconds, along with the simple experimental conditions and its cost-effectiveness, strongly support the approach as an alternative to current procedures.

Graphene oxide and graphene oxide functionalized with silver nanoparticles as adsorbents of phosphates in waters. A comparative study.

Phosphate removal is an important factor that must be taken into account in eutrophized waters. For this reason, many studies on different ways of removing phosphates from water have been published nowadays. In this work, a comparative study between the use of graphene oxide (GO) and graphene oxide functionalized with silver nanoparticles (GO@AgNPs) as adsorbents to remove phosphates from water samples has been carried out. Experimental conditions, including the pH, adsorbent dose, contact time and temperature, have been analyzed to achieve the highest adsorption efficiency. Although both adsorbents can be considered suitable for removing phosphates from aqueous solutions, GO@AgNPs provided a maximum removal efficiency of 100%, reaching the equilibrium conditions instantaneously under straightforward experimental conditions. Moreover, a much lower adsorbent dose was necessary than with graphene oxide. When GO was used, the maximum removal efficiency was 75%, 9 min were necessary to reach the equilibrium conditions and 20 mg of adsorbent were needed. Both adsorbents can be regenerated in an acid medium, giving recovery percentages of 98% and 80% for GO and GO@AgNPs respectively, which allows them to be recycled and used again.

The Pilates method and cardiorespiratory adaptation to training.

Although all authors report beneficial health changes following training based on the Pilates method, no explicit analysis has been performed of its cardiorespiratory effects. The objective of this study was to evaluate possible changes in cardiorespiratory parameters with the Pilates method. A total of 45 university students aged 18-35 years (77.8% female and 22.2% male), who did not routinely practice physical exercise or sports, volunteered for the study and signed informed consent. The Pilates training was conducted over 10 weeks, with three 1-hour sessions per week. Physiological cardiorespiratory responses were assessed using a MasterScreen CPX apparatus. After the 10-week training, statistically significant improvements were observed in mean heart rate (135.4-124.2 beats/min), respiratory exchange ratio (1.1-0.9) and oxygen equivalent (30.7-27.6) values, among other spirometric parameters, in submaximal aerobic testing. These findings indicate that practice of the Pilates method has a positive influence on cardiorespiratory parameters in healthy adults who do not routinely practice physical exercise activities.

Hiperinsulinisme en una unitat neonatal / Hiperinsulinismo en una unidad neonatal / Hyperinsulinism in a newborn unit

Introducció: lhiperinsulinisme (HI) és la causa més freqüent dhipoglucèmia neonatal mantinguda. Es pot dividir en transitori o secundari i persistent o congènit. Es presenta una revisió del tema, a partir de quatre casos diagnosticats a la nostra unitat durant set anys. Observació clínica: dels quatre casos, tres són transitoris o secundaris i un persistent. Els factors predisposants dels transitoris són la pèrdua del benestar fetal i la diabetis gestacional. El persistent, amb una ressonància magnètica (RM) cranial i un estudi genètic normals, no va respondre al tractament amb diazòxid (DI) i va millorar amb dextrinomaltosa i alimentació contínua. Cap cas va presentar seqüeles neurològiques. Comentaris: els nostres casos compleixen els criteris diag-nòstics dHI. La incidència dHI al nostre centre és d1/4.500 nascuts vius i la dHI persistent d1/20.000 nascuts vius en set anys. LHI transitori o secundari es relaciona amb lasfíxia neonatal, el retard del creixement intrauterí i la diabetis gestacional. Els casos descrits presen-ten pèrdua del benestar fetal i diabetis. El tractament inicial és laportació de glucosa. Després, el fàrmac de primera línia és el DI. LHI persistent acostuma a no respondre al tractament i pot ser focal o difús, el primer dels quals es pot beneficiar de cirurgia. El màxim objectiu és la prevenció de seqüeles neurològiques. És fonamental el maneig conjunt amb un especialista endocrinòleg

Introducción. El hiperinsulinismo (HI) es la causa más frecuente de hipoglucemia neonatal mantenida. Se puede dividir en transitorio o secundario y persistente o congénito. Se presenta una revisión del tema, a partir de cuatro casos diagnosticados en nuestra unidad durante siete años. Observación clínica. De los cuatro casos, tres son transitorios o secundarios y uno persistente. Los factores predisponentes de los transitorios son la pérdida del bienestar fetal y la diabetes gestacional. El persistente, con una resonancia magnética (RM) craneal y un estudio genético normales, no respondió al diazóxido (DI) y mejoró con dextrinomaltosa y alimentación continua. Ningún caso presentó secuelas neurológicas. Comentarios. Nuestros casos cumplen los criterios diagnósticos de HI. La incidencia de HI en nuestro centro es de 1/4.500 nacidos vivos y la de HI persistente de 1/20.000 nacidos vivos en siete años. El HI transitorio o secundario se relaciona con la asfixia neonatal, el retraso del crecimiento intrauterino y la diabetes gestacional. Los casos descritos presentan pérdida del bienestar fetal y diabetes. El tratamiento inicial es el aporte de glucosa. Después, el fármaco de primera linea es el DI. El HI persistente acostumbra a no responder al tratamiento y puede ser focal o difuso, el primero de los cuales puede beneficiarse de cirugía. El máximo objetivo es la prevención de secuelas neurológicas. Es fundamental el manejo conjunto con un especialista endocrinólogo (AU)

Introduction. Hyperinsulinism (HI) is the most frequent cause of sustained neonatal hypoglycemia; it can be transient (secondary) or persistent (congenital). We describe four cases of neonatal HI seen in a neonatal unit over a seven-year period. Clinical observation. Three of the four cases were transient or secondary, and the other was persistent. Loss of fetal wellbeing and gestational diabetes were the predisposing factors in the three transient cases. The case of persistent HI had normal brain magnetic resonance imaging and genetics; it did not respond to treatment wth diazoxide (DI) but improved with continuous feeding and dextrinomaltose. All four cases recovered with no neurological sequelae. Comments. Our fours cases met the diagnosis criteria for HI. Over the seven-year period, the overall incidence of HI was 1 in 4,500 live births, while the incidence of persistent HI was 1 in 20,000 live births. Transient or secondary HI is related to birth asphyxia, intrauterine growth retardation, and gestational diabetes. The initial treatment of HI is with glucose and DI. Persistent or congenital HI seldom responds to treatment and it can be the result of focal or diffuse pancreatic disease, the first of which anomalies could benefit from surgery. Prevention of neurological sequelae is the main objective of the treatment. A multidisciplinary management with endocrinology is recommended (AU)

Ab initio and shell model studies of structural, thermoelastic and vibrational properties of SnO2 under pressure.

The pressure dependences of the structural, thermoelastic and vibrational properties of SnO2 in its rutile phase are studied, as well as the pressure-induced transition to a CaCl2-type phase. These studies have been performed by means of ab initio (AI) density functional theory calculations using the localized basis code SIESTA. The results are employed to develop a shell model (SM) for application in future studies of nanostructured SnO2. A good agreement of the SM results for the pressure dependences of the above properties with the ones obtained from present and previous AI calculations as well as from experiments is achieved. The transition is characterized by a rotation of the Sn-centered oxygen octahedra around the tetragonal axis through the Sn. This rotation breaks the tetragonal symmetry of the lattice and an orthorhombic distortion appears above the critical pressure P(c). A zone-center phonon of B1g symmetry in the rutile phase involves such rotation and softens on approaching Pc. It becomes an Ag mode which stabilizes with increasing pressure in the CaCl2 phase. This behavior, together with the softening of the shear modulus (C11-C12)/2 related to the orthorhombic distortion, allows a precise determination of a value for Pc. An additional determination is provided by the splitting of the basal plane lattice parameters. Both the AI and the experimentally observed softening of the B(1g) mode are incomplete, indicating a small discontinuity at the transition. However, all results show continuous changes in volume and lattice parameters, indicating a second-order transition. All these results indicate that there should be sufficient confidence for the future employment of the shell model.

Ab initio study of the elastic properties of single and polycrystal TiO(2), ZrO(2) and HfO(2) in the cotunnite structure.

In this work, we study theoretically the elastic properties of the orthorhombic (Pnma) high-pressure phase of IV-B group oxides: titania, zirconia and hafnia. By means of the self-consistent SIESTA code, pseudopotentials, density functional theory in the LDA and GGA approximations, the total energies, hydrostatic pressures and stress tensor components are calculated. From the stress-strain relationships, in the linear regime, the elastic constants C(ij) are determined. Derived elastic constants, such as bulk, Young's and shear modulus, Poisson coefficient and brittle/ductile behavior are estimated with the polycrystalline approach, using Voigt-Reuss-Hill theories. We have found that C(11), C(22) and C(33) elastic constants of hafnia and zirconia show increased strength with respect to the experimental values of the normal phase, P 2(1)/c. A similar situation applies to titania if these constants are compared with its normal phase, rutile. However, shear elastic constants C(44), C(55) and C(66) are similar to the values found in the normal phase. This fact increases the compound anisotropy as well as its ductile behavior. The dependence of unit-cell volumes under hydrostatic pressures is also analyzed. P-V data, fitted to third-order Birch-Murnaghan equations of state, provide the bulk modulus B(0) and its pressure derivatives B'(0). In this case, LDA estimations show good agreement with respect to recent measured bulk moduli of ZrO(2) and HfO(2). Thermo-acoustic properties, e.g. the propagation speed of transverse, longitudinal elastic waves together with associated Debye temperatures, are also estimated.

Effective temperature in relaxation of Coulomb glasses.

We study relaxation in two-dimensional Coulomb glasses up to macroscopic times. We use a kinetic Monte Carlo algorithm especially designed to escape efficiently from deep valleys around metastable states. We find that, during the relaxation process, the site occupancy follows a Fermi-Dirac distribution with an effective temperature much higher than the real temperature T. Long electron-hole excitations are characterized by T(eff), while short ones are thermalized at T. We argue that the density of states at the Fermi level is proportional to T(eff) and is a good thermometer to measure it. T(eff) decreases extremely slowly, roughly as the inverse of the logarithm of time, and it should affect hopping conductance in many experimental circumstances.

Ab initio localized basis set study of structural parameters and elastic properties of HfO2 polymorphs.

The SIESTA approach based on pseudopotentials and a localized basis set is used to calculate the electronic, elastic and equilibrium properties of P 21/c, Pbca, Pnma, Fm3m, P42nmc and Pa3 phases of HfO2. Using separable Troullier-Martins norm-conserving pseudopotentials which include partial core corrections for Hf, we tested important physical properties as a function of the basis set size, grid size and cut-off ratio of the pseudo-atomic orbitals (PAOs). We found that calculations in this oxide with the LDA approach and using a minimal basis set (simple zeta, SZ) improve calculated phase transition pressures with respect to the double-zeta basis set and LDA (DZ-LDA), and show similar accuracy to that determined with the PPPW and GGA approach. Still, the equilibrium volumes and structural properties calculated with SZ-LDA compare better with experiments than the GGA approach. The bandgaps and elastic and structural properties calculated with DZ-LDA are accurate in agreement with previous state of the art ab initio calculations and experimental evidence and cannot be improved with a polarized basis set. These calculated properties show low sensitivity to the PAO localization parameter range between 40 and 100 meV. However, this is not true for the relative energy, which improves upon decrease of the mentioned parameter. We found a non-linear behaviour in the lattice parameters with pressure in the P 21/c phase, showing a discontinuity of the derivative of the a lattice parameter with respect to external pressure, as found in experiments. The common enthalpy values calculated with the minimal basis set give pressure transitions of 3.3 and 10.8 GPa for [Formula: see text] and [Formula: see text], respectively, in accordance with different high pressure experimental values.

Repercusión hemodinámica e hidroelectrolítica del ayuno de Ramadán en escolares adolescentes / Haemodynamic and hydrosalinum repercussion on adolescents who practise Ramadan fast

Justificación: el Ramadán se caracteriza por un período de ayuno acompañado de restricción hídrica durante el día, cambiando la ingesta de sólidos y líquidos a la noche durante un mes lunar. El propósito de este estudio ha sido valorar en un grupo de escolares adolescentes, la influencia del ayuno del Ramadán en el equilibrio hidrosalino. Metodología: para ello se seleccionaron de forma aleatoria un grupo de adolescentes escolarizados en centros multiconfesionales de la Ciudad Autónoma de Ceuta, que tras ser convenientemente informados aceptaron participar voluntariamente en el estudio. Se han analizado parámetros fisiológicos como peso, talla, frecuencia cardíaca, presión arterial, electrolitos en plasma y orina, osmolaridad, volumen plasmático y concentraciones hormonales de renina, aldosterona y vasopresina o ADH. Dichos parámetros se determinaron antes (A), durante (B y C) y después (D) del Ramadán. Resultados: los valores de aldosterona disminuyeron en la primera semana del Ramadán (B) y se elevaron considerablemente en las siguientes (A: 410,6ñ47,65; B: 278,2ñ27,60; C: 528,12ñ50,37 y D: 578,12ñ78,24 pg/mL), mientras que la ADH no se modificó significativamente en la primera semana de ayuno (B), disminuyendo en las posteriores (A: 9,1ñ0,78; B:8,9ñ0,79; C: 5,65ñ0,08 y D: 6,22ñ0,32 pg/mL). Los niveles plasmáticos de Na+ y K+ y sus fracciones de excreción mostraron variaciones coherentes con las de dichas hormonas. Conclusiones: la hiperhidratación debida a la ingesta excesiva de agua antes de salir el sol, provoca una hemodilución con disminución de la osmolaridad y mantenimiento del volumen plasmático y presión arterial (PA) a expensas de la inhibición de vasopresina o ADH y de Renina. El aumento en los niveles de K+ plasmáticos, sería responsable de la secreción significativamente elevada de aldosterona (p<0,05), observada el día 21de ayuno (C) y del aumento concomitante de la fracción de excreción de K+ (p<0,05) (AU)

Effects of human recombinant erythropoietin on inflammatory status in peritoneal dialysis patients.

Treatment with recombinant human erythropoietin (rHuEPO) in dialysis patients has been associated with improvement of nutritional and immune status through an increase of cytokine production [such as tumor necrosis factor alpha (TNF alpha)]. The high cytokine production can be a double-edged sword owing to the relationship of cytokines with the systemic inflammatory process, which has been associated with many complications of uremic status. Our aim was to analyze the medium-long term effects of rHuEPO treatment on uremic inflammatory markers. We studied 45 peritoneal dialysis (PD) patients divided in two groups: a rHuEPO group (40-70 subcutaneous units/kg weekly) and a control group (no rHuEPO). The treated group was analyzed in four periods. Period 1 (rHuEPO-1) included 24 patients who had been using rHuEPO at long-term. Period 2 (rHuEPO-2; n = 21) looked at the patients 2 months after rHuEPO withdrawal. Period 3 (rHuEPO-3; n = 19) looked at the patients after 2 months under rHuEPO therapy. Period 4 (rHuEPO-4; n = 17) looked at the patients after 4 months on rHuEPO treatment. With the reintroduction of rHuEPO, we observed a progressive, statistically significant (p < 0.05), and temporary increase in TNF alpha plasma levels, from 44 +/- 24 pg/mL (rHuEPO-2) to 76.8 +/- 25 pg/mL (rHuEPO-3), and then to 83 +/- 27 pg/mL (rHuEPO-4). But in the long term, TNF alpha decreased [33.5 +/- 10 pg/mL (rHuEPO-1)]. Similarly, albumin increased in the short term (3.73 +/- 0.5 g/dL to 4 +/- 0.5 g/dL, and then to 4 +/- 0.43 g/dL), and then decreased (3.8 +/- 0.44 g/dL). The normalized protein catabolic rate (nPCR) increased from 1 +/- 0.2 g/kg daily to 1.12 +/- 0.3 g/kg daily (rHuEPO-4). Long term, nPCR decreased to 1.06 +/- 0.3 g/kg daily. Leptin initially increased (60.1 +/- 48 ng/mL to 42.8 +/- 22 ng/mL, and then to 38 +/- 18.2 ng/mL); it also increased in the long term (62 +/- 50.9, p < 0.05). At baseline, we found a significant positive linear correlation (p < 0.05) between TNF alpha and leptin (r = 0.52), TNF alpha and C-reactive protein [(CRP) r = 0.4], CRP and leptin (r = 0.49), fibrinogen and CRP (r = 0.78, p < 0.01), fibrinogen and leptin (r = 0.37), and leptin and body mass index [(BMI) r = 0.67]. In conclusion, rHuEPO induces a temporary, non inflammatory immune hyperactivity mediated by TNF alpha, without the adverse effects associated with that cytokine. By decreasing leptin, rHuEPO could increase food intake and improve the nutritional status of PD patients. At baseline, we confirm the existence of a chronic inflammatory process in uremia.

Influencia del estilo de vida en el perfil lipídico / Influence of life style in the lipidic profile

En este trabajo se ha analizado la relación entre el estilo de vida y el perfil lipídico, como factor de riesgo para la salud. Se han seleccionado 15 sujetos deportistas “senior” sanos, atletas especialistas en carrera de fondo, con una media de edad de 51 años, 69 Kg como peso medio y 1,69m como estatura media. Su participación en el estudio fue voluntaria, junto a la de otros 12 sujetos sedentarios y de similares características socioculturales, que configuraron el grupo control, con una media de edad de 49 años, un peso medio de 83 Kg y una talla de 1,72 m. Se ha utilizado el cuestionario de estilos de vida de Heyward sobre hábitos relacionados con la bebida, tabaco, ejercicio físico y dieta, así como la determinación de los niveles de lípidos en sangre (TG, Colesterol total, HDL, LDL, VLDL, y cociente LDL/ HDL Se han comparado los niveles basales de lípidos en ambos grupos con relación al estilo de vida. Los resultados de nuestro trabajo muestran hábitos menos saludables en el grupo de sujetos sedentarios, con mayor ingesta de alcohol y tabaco y significativamente menor realización de ejercicio físico que en el grupo de atletas. El perfil lipídico muestra valores inferiores de colesterol total, triglicéridos, LDL,VLDL, LDL/HDL y mayores de HDL en el grupo de atletas cuyo consumo de alcohol es menor, no consumen tabaco y entrenan de forma regular. El ejercicio físico en nuestro estudio se constituye como el hábito de mayor relevancia en la configuración de unas características antropométricas y un perfil lipídico óptimos para la promoción de la salud y desarrollo de estilos de vida saludables (AU)

[Prevalence of genetic prothrombotic factors (factor V Leiden and II20210 prothrombin mutation) in glomerular nephropathies with or without thrombosis]. / Prevalencia de factores protrombóticos de base genética (factor V Leiden y mutación II20210 de la protrombina) en nefropatías glomerulares con o sin trombosis.

The presence of genetic prothrombotic factors (factor V Leiden and the prothrombin II20210 mutation) was investigated in 38 patients with glomerulonephritis with or without a history of thrombotic events and/or nephrotic syndrome. We found an increased prevalence (36%) of heterozygous factor V Leiden in those patients with a history of thrombotic events. This is ten times the prevalence in the normal Spanish population. Carrier status for this mutation may be a determining factor in the development of thrombotic events along with the acquired disorders of coagulation to which these patients are prone. We found only one patient who was a carrier of the G-A II20210 mutation of the prothrombin gene; this patient had no history of venous thrombosis or embolism. Our findings suggest the need to measure activated protein C resistance and to look for the most frequent genotype causing it, Factor V Leiden, in patients with glomerulonephritis to identify those at risk who may benefit from prophylaxis against thrombosis.

Prevalencia de factores protrombóticos de base genética (factor V Leiden y mutación II20210 de la protrombina) en nefropatías glomerulares con o sin trombosis / Prevalence of genetic protrombotic factors (factor V Leiden and protrombin II20210 mutation) in glomerular nephropathies with or without thrombosis

Se investigó de forma prospectiva en 38 pacientes portadores de nefropatías glomerulares, con o sin antecedentes de síndrome nefrótico y/o manifestaciones tromboembólicas, la presencia de factores protrombóticos de base genética (factor V Leiden y mutación 1120210 de la protrombina), comprobando una elevada prevalencia de factor V Leiden (36 por ciento) en aquellos que tenían antecedentes de manifestaciones trombóticas, 10 veces superior a la de la población normal en nuestra Área de Salud (4 por ciento), y similar a la de pacientes no nefrológicos con enfermedad tromboembólica venosa. La situación de portador de esta mutación podría ser un factor determinante en la aparición de trombosis, en asociación con otros trastornos adquiridos de la coagulación que tienen lugar en estos pacientes. Por lo que respecta a la mutación 11202,0 de la protrombina estuvo presente sólo en un caso aunque en ausencia de manifestaciones de enfermedad tromboembólica venosa. Creemos aconsejable, por tanto, la determinación de la resistencia a la proteína C activada y su genotipo más frecuente, el factor V Leiden, en enfermos con glomerulonefritis con vistas a posibles actuaciones de profilaxis tromboembólica (AU)

Effects of recombinant human erythropoietin on functional and injury endothelial markers in peritoneal dialysis patients.

Clinical effects of recombinant human erythropoietin (rHuEPO) such as thrombosis, convulsions, hyperviscosity, hypertension, and angiogenic effect in culture cells have been described. We studied the rHuEPO effect on endothelial damage markers and endothelial function markers: tissue-type plasminogen activator (t-PA), nitrate (NO3), thrombomodulin (TM), and von Willebrand factor (vWF). Twenty-six peritoneal dialysis patients treated with rHuEPO and 19 controls were included. The study design for rHuEPO patients consisted of four periods: long-term treatment (rHuEPO-1); 2 months of withdrawal (rHuEPO-2); and 4 months on 5000 IU/week rHuEPO subcutaneously, with markers being measured after 2 months (rHuEPO-3) and after 4 months (rHuEPO-4). After 2 months of rHuEPO withdrawal, a decrease in hemoglobin level appeared (11+/-1.8 g/dL to 9.2+/-1.5 g/dL, p < 0.01). After rHuEPO reintroduction, this value reached 10.6+/-1.5 g/dL at two months, and 11.1+/-1.4 g/dL at four months. A significant increase in t-PA ratio was observed from two months without rHuEPO to two months on rHuEPO, returning to previous values after four months. Similarly, TM increased for patients with creatinine clearances (CrC) < 5 mL/min. No changes in the higher-than-normal plasma vWF levels were found during the various periods. A statistically significant lower value was found in controls compared with rHuEPO-4 patients. A statistically significant increase in NO3 levels was observed in the pre-venous occlusion (VO) test immediately after the re-introduction of rHuEPO. This increment returned to prior values four months after rHuEPO was reintroduced. Our results show that rHuEPO treatment causes an increase in some endothelial damage markers (TM, t-PA) and modifies endothelial function markers (t-PA ratio, NO3). These changes might favor thrombosis and atherosclerosis.

Fibrinolytic activity in laparoscopic cholecystectomy.

The aim of this study was to examine the fibrinolytic activity in laparoscopic cholecystectomy (LC) to determine whether changes occur that might indicate a greater risk of thrombosis. The study was carried out in 20 patients who had undergone laparoscopic surgery for cholelithiasis without complications. The average age was 59.4 years (34-77 years). Seventy-five percent were women. The mean operating time was 70 minutes (35-120 minutes). Pneumoperitoneum at 14 mm Hg was maintained in all patients, and they were in 30 degrees reverse Trendelenburg position. Postoperative mobilization was obtained before 24 hours, and patients were discharged 48 hours after surgery. The control group was composed of 12 patients, evenly distributed by age, sex, and length of surgery, who had undergone Bassini herniorrhaphy without complications or relapses. The following hemostatic parameters were studied: plasma fibrinolytic activity (PFA), euglobulin fibrinolytic activity (EFA), tissue-type plasminogen activator (t-PA), fast-acting plasminogen activator inhibitor-1 (PAI-1), and D-dimer (D-D). Samples were obtained at the following times: (1) under basal conditions the day before surgery, (2) preoperatively, (3) at the end of surgery, (4) 24 hours after surgery, and (5) on the seventh day following surgery. No patient had clinical manifestations of thromboembolic disease immediately after surgery or during an average follow-up period of 16 months (range 15-18 months). Analysis of the results of global fibrinolysis showed that fibrinolytic activity was enhanced only in the postoperative period (third sample) of the LC patients. The fraction of euglobulins enhances fibrinolytic activity in both groups in the third sample with regard to the other determinations; the LC patients showed a higher degree of significance (p<0.005). A significant increase of postoperative t-PA in both groups was found, being more significant in the LC group (p<0.005). In the PAI-1 values, no significant differences existed between either determinations or groups. A significant increase in D-dimer (p<0.05) occurred in the immediate postoperative period (third sample) and 24 hours later (fourth sample), returning to normal basal values on the seventh day. No significant differences were found between the two groups. These results seem to indicate that LC produces an increase in the fibrinolytic activity in plasma as a result of the liberation of tissue plasminogen activator from the venous endothelium, which could indicate hypocoagulability during the immediate postoperative period and, therefore, signify less thrombotic risk for patients undergoing this procedure.