SARS-CoV-2 infection in Spanish children with chronic kidney pathologies.

BACKGROUND: There is little information about Coronavirus Disease 2019 (COVID-19) in children with underlying chronic renal pathologies. CASES REPORT: From March until April 15, 2020, 16 children with chronic renal pathologies were diagnosed with COVID-19 in Spain. Of these, 6 had end-stage kidney disease (ESKD) (3 transplant recipients and 3 on chronic hemodialysis). The severity of symptoms was mild in all the patients, with little radiological involvement. Three patients were asymptomatic. Fever and upper respiratory symptoms were the most frequent findings. Basal glomerular filtration worsened in 3 patients; however, recovery was rapidly achieved with rehydration and drug dose adjustment. In 2 patients diagnosed with steroid-dependent nephrotic syndrome, COVID-19 provoked a disease relapse. None required oxygen therapy, and 7 could be managed as outpatients. CONCLUSIONS: COVID-19 disease appears to have a similar clinical course in children with underlying chronic renal pathologies, even in immunosuppressed cases, as in healthy children of the same age; however, special attention must be paid to fluid management and drug dose adjustment.

Evaluation of a CFD-based approach to estimate pollutant distribution within a real urban canopy by means of passive samplers.

The distribution of pollutants is spatially heterogeneous within urban streets making difficult to build a realistic concentration map. In this paper, a methodology based on computational fluid dynamic modeling with Reynolds-averaged Navier-Stokes approach is used to compute maps of concentration for a period of several weeks. The methodology is evaluated by comparing simulation results against experimental data from two different campaigns where a large number of passive samplers deployed in an area with heavy vehicular traffic in Madrid (Spain). The evaluation shows that the methodology is able to reproduce the general pattern of several-week averaged pollutant distribution in an urban area with heavy vehicular traffic, resolving the spatial variability up to a resolution of 1-2m. In addition, the model results fit satisfactorily the time evolution of the pollutant concentration measured at an air quality station deployed in the studied area. However, problems were detected close to zones with complex emissions patterns (tunnels, street forks, etc.), where the model compared poorly against passive sampler measurements. A preliminary assessment of the uncertainties induced in the numerical methodology due to consider NO2 as non-reactive pollutant under winter conditions indicates that it would be an acceptable approach for this particular case study. Overall, our analysis contributes to raise the confidence in that approached similar to the one presented in this study can be adopted for dealing with several aspects of the air quality management such as air quality assessment, optimization of the location of measurement stations, and the evaluation of air pollution reduction strategies.

Nefrectomías en riñón no funcionante, ¿estamos haciendo lo correcto? / Nephrectomies in poor or non-functioning kidneys. Is it the right thing to do?

Objetivos. Presentar nuestra experiencia en el manejo quirúrgico del riñón poco o no funcionante, revisando las indicaciones de nefrectomía y sus resultados a largo plazo. Material y métodos. Estudio retrospectivo de los pacientes intervenidos de nefrectomía en nuestro centro entre los años 2010 y 2014. Se revisaron sus historias clínicas y se recogieron una serie de variables sociodemográficas y clínicas, prestando especial atención a la resolución o no de la sintomatología que motivó la cirugía. Resultados. Realizamos un total de 18 nefrectomías. La edad media fue de 6,5 años (11 meses - 15 años). La indicación de cirugía se realizó por infecciones del tracto urinario (ITUS) de repetición en 7 casos, hipertensión arterial renovascular (HTAR) en 5, dolor en 2, aumento de tamaño en 2 y dificultad para el seguimiento en otros 2 pacientes. La nefrectomía se realizó vía laparoscópica en 16 casos y abierta en 2. La mediana de la estancia hospitalaria fue de 48 horas. La tasa de complicaciones fue del 5,55% tanto intraoperatoriamente (1 caso de sangrado) como postoperatoriamente (1 caso de enfisema subcutáneo). En todos los casos se objetivó resolución de la sintomatología salvo en 3, 2 pacientes presentaron ITUS y 1 HTA persistente. Conclusiones. La nefrectomía es un procedimiento seguro en niños con una tasa baja de complicaciones. La selección adecuada de los casos y un correcto estudio multidisciplinar previo son aspectos fundamentales para obtener buenos resultados clínicos y evitar complicaciones postoperatorias

Aim of the study. To review our management and outcomes of nephrectomies performed in patients with non-functioning kidneys. Methods. Retrospective analysis of the patients who underwent nephrectomy surgery in our hospital between 2010 and 2014. Data was collected from the patient charts paying special attention to the clinical resolution of the symptoms that motivated surgery. Main results. A total of 18 nephrectomies were performed. Median age was of 6,5 years (range: 11 months to 15 years). Surgery was indicated by recurrent urinary tract infections (UTI) in 7 cases, renovascular hypertension (RHT) in 5, pain in 2, increasing size in 2 and parents’ preference due to poor compliance with follow up in 2 patients. 16 nephrectomies were performed laparoscopically and 2 were open procedures. Median hospital length of stay was 48 hours. Complication rate was 5.55% both for the intraoperatively (1 case of bleeding) and post operatively (1 case of subcutaneous emphysema). Signs and symptoms were successfully resolved in all cases except for 3, 2 patients had an UTI and 1 persistent RHT. Conclusions. Nephrectomy is a safe surgical procedure in children with a low rate of complications. An appropriate selection of the cases and a thorough preoperative multidisciplinary assessment are essential aspects to obtain good clinical results and to avoid post-operative complications

[Nephrectomies in poor or non-functioning kidneys. Is it the right thing to do?] / Nefrectomías en riñón no funcionante, ¿estamos haciendo lo correcto?

AIM OF THE STUDY: To review our management and outcomes of nephrectomies performed in patients with non-functioning kidneys. METHODS: Retrospective analysis of the patients who underwent nephrectomy surgery in our hospital between 2010 and 2014. Data was collected from the patient charts paying special attention to the clinical resolution of the symptoms that motivated surgery. MAIN RESULTS: A total of 18 nephrectomies were performed. Median age was of 6,5 years (range: 11 months to 15 years). Surgery was indicated by recurrent urinary tract infections (UTI) in 7 cases, renovascular hypertension (RHT) in 5, pain in 2, increasing size in 2 and parents' preference due to poor compliance with follow up in 2 patients. 16 nephrectomies were performed laparoscopically and 2 were open procedures. Median hospital length of stay was 48 hours. Complication rate was 5.55% both for the intraoperatively (1 case of bleeding) and post operatively (1 case of subcutaneous emphysema). Signs and symptoms were successfully resolved in all cases except for 3, 2 patients had an UTI and 1 persistent RHT. CONCLUSIONS: Nephrectomy is a safe surgical procedure in children with a low rate of complications. An appropriate selection of the cases and a thorough preoperative multidisciplinary assessment are essential aspects to obtain good clinical results and to avoid post-operative complications.

OBJETIVOS: Presentar nuestra experiencia en el manejo quirúrgico del riñón poco o no funcionante, revisando las indicaciones de nefrectomía y sus resultados a largo plazo. MATERIAL Y METODOS: Estudio retrospectivo de los pacientes intervenidos de nefrectomía en nuestro centro entre los años 2010 y 2014. Se revisaron sus historias clínicas y se recogieron una serie de variables sociodemográficas y clínicas, prestando especial atención a la resolución o no de la sintomatología que motivó la cirugía. RESULTADOS: Realizamos un total de 18 nefrectomías. La edad media fue de 6,5 años (11 meses - 15 años). La indicación de cirugía se realizó por infecciones del tracto urinario (ITUS) de repetición en 7 casos, hipertensión arterial renovascular (HTAR) en 5, dolor en 2, aumento de tamaño en 2 y dificultad para el seguimiento en otros 2 pacientes. La nefrectomía se realizó vía laparoscópica en 16 casos y abierta en 2. La mediana de la estancia hospitalaria fue de 48 horas. La tasa de complicaciones fue del 5,55% tanto intraoperatoriamente (1 caso de sangrado) como postoperatoriamente (1 caso de enfisema subcutáneo). En todos los casos se objetivó resolución de la sintomatología salvo en 3, 2 pacientes presentaron ITUS y 1 HTA persistente. CONCLUSIONES: La nefrectomía es un procedimiento seguro en niños con una tasa baja de complicaciones. La selección adecuada de los casos y un correcto estudio multidisciplinar previo son aspectos fundamentales para obtener buenos resultados clínicos y evitar complicaciones postoperatorias.

Criterios en la selección de pacientes para optimizar resultados en liposucción asistida por láser de abdomen y flancos: análisis de 340 cirugías / Patient selection criteria to optimize results in laser-assisted liposuction of the abdomen and flanks: analysis of 340 surgeries

El objetivo de nuestro estudio es valorar mediante ecografía y análisis estadístico la respuesta a la liposucción asistida por láser en abdomen y flancos. Para ello, se tuvo en cuenta la disminución del tejido adiposo, la retracción cutánea y el grado de satisfacción de las pacientes con los resultados. Realizamos un estudio retrospectivo sobre 340 cirugías en pacientes multíparas mayores de 40 años, con o sin diástasis de rectos, que rechazaron la abdominoplastia con lipectomía. Las intervenciones se efectuaron mediante liposucción a respectivamente en 924 y 9/5 11111, bajo sedo-analgesia y con anestesia tumescente. Los láseres se programaron para emisión en modo continuo, actuando al unísono con potencia de 20 W hasta alcanzar un promedio de entre 10 a 12 kJ de energía acumulada para los flancos, y de entre 12 a 18 kJ para el abdomen. La valoración subjetiva y objetiva se realizó mediante escala GAIS (Global Aesthetic Improvement Scale). Se tomaron fotografías antes, 1 y 6 meses después de la intervención. En abdomen se realizaron ecografías antes y 6 meses después de la cirugía, y se empleó t de Student como test de contraste para el estudio analítico. En 60 pacientes seleccionados aleatoriamente como muestra representativa se realizaron fotografías digitales de la superficie de la piel a fin de valorar comparativamente por programa de ordenador la textura-flacidez de la condición del tejido antes, 1 y 6 meses después de la cirugía. En ninguno de los resultados se observó isquemia y/o quemaduras. La disminución del tejido adiposo, según las ecografías, fue estadísticamente significativa (p<0,05) comparativamente a los 6 meses del tratamiento. La valoración de las fotografías antes y 6 meses después de la cirugía por un médico ajeno al estudio, al igual que la textura-flacidez cutánea, fue Buena o Muy Buena. La valoración subjetiva por cuestionarios de escala GAIS alcanzó un 57,1% (194 pacientes) al sumar los resultados Buenos y Muy Buenos. En cambio, la valoración objetiva por el médico fue sensiblemente superior, un 74% (252 pacientes). En conclusión, según los estudios realizados creemos que la liposucción asistida por láser es una técnica eficaz y reproducible, que obtiene notables resultados cuando las pacientes presentan depósitos de grasa localizada y no sudominales como consecuencia de partos múlti-sufren diástasis de los rectos abdominales como consecuencia de partos múltiples. También es importante que, de forma ideal, las pacientes no presenten un índice de masa grasa corporal (BMI) superior a 26 para predecir y obtener óptimos resultados (AU)

Ultrasound and statistical analysis of results of laser-assisted liposuction of the abdomen and flanks have been evaluated. Decrease in fat tissue, skin retraction and patient satisfaction with results have all been taken into consideration. This retrospective study corresponds to 340 surgeries, done on multiparous patients over 40 years age, with and without abdominal recti muscle diastasis that rejected going through abdominal lipectomy. Surgeries were carried out by laser assisted liposuction with two Diode lasers emitting at 924 and 975 nm, operating simultaneously, performed under sedation and analgesia, and injecting tumescent anaesthesia. Lasers were programmed for emission in continuous mode with both systems operating at a power of 20W, reaching a total mean accumulated energy of between 10 and 12 kJ for flanks, and between 12 and 18 kJ for the abdomen. Subjective and objective evaluation was carried out using a GAIS scale (Global Aesthetic Improvement Scale). Photographs were taken before, 1 and 6 months after procedures. For the abdomen ultrasound examination were done before and 6 months after surgery, and Student's t-test was implemented for the statistical analysis. In 60 patients, randomly chosen as a representative sample, digital photographs of the skin surface were taken in order to comparatively evaluate skin texture-laxity condition, before, 1 and 6 months after surgery with the aid of a computer programme. No ischemia or burns were observed in any patient. According to ultrasound exam, decrease in fat tissue was statistically significant (p<0,05) when compared to 6 months after surgery. Evaluation by an independent doctor to the study, before and 6 months after photographs as well as the skin texture-laxity, were Good and Very Good. Subjective results obtained through questionnaires using GAIS scale reached 57,1% (194 patients) satisfied with results, totalling the Good and Very Good results. However, the objective evaluation, done by the Doctor, was significantly better regarding results obtained, 74% (252 patients). In conclusion, laser assisted liposuction is an effective and reproducible technique that obtains notable results when patients presented localized fat deposits and did not suffer diastasis due to multiple pregnancies. It is also important that, ideally, patients selected should not have a BMI of over 26 in order to obtain optimal results (AU)

Determination of beryllium by electrothermal atomic absorption spectrometry using tungsten surfaces and zirconium modifier.

Electrothermal atomization of beryllium from graphite and tungsten surfaces was compared with and without the use of various chemical modifiers. Tungsten proved to be the best substrate, giving the more sensitive integrated atomic absorption signals of beryllium. Tungsten platform atomization with zirconium as a chemical modifier was used for the determination of beryllium in several NIST SRM certified reference samples, with good agreement obtained between the results found and the certified values. The precision of the measurements (at 10 microgL(-1)), the limit of detection (3sigma), and the characteristic mass of beryllium were 2.50%, 0.009 microgL(-1) and 0.42 pg, respectively.

Low level radioactivity measurements with phoswich detectors using coincident techniques and digital pulse processing analysis.

A new system has been developed for the detection of low radioactivity levels of fission products and actinides using coincidence techniques. The device combines a phoswich detector for alpha/beta/gamma-ray recognition with a fast digital card for electronic pulse analysis. The phoswich can be used in a coincident mode by identifying the composed signal produced by the simultaneous detection of alpha/beta particles and X-rays/gamma particles. The technique of coincidences with phoswich detectors was proposed recently to verify the Nuclear Test Ban Treaty (NTBT) which established the necessity of monitoring low levels of gaseous fission products produced by underground nuclear explosions. With the device proposed here it is possible to identify the coincidence events and determine the energy and type of coincident particles. The sensitivity of the system has been improved by employing liquid scintillators and a high resolution low energy germanium detector. In this case it is possible to identify simultaneously by alpha/gamma coincidence transuranic nuclides present in environmental samples without necessity of performing radiochemical separation. The minimum detectable activity was estimated to be 0.01 Bq kg(-1) for 0.1 kg of soil and 1000 min counting.

Synthesis of Ni-Mo-W sulfide nanorods as catalyst for hydrodesulfurization of dibenzothiophene.

Two trimetallic sulfurs, MoWNiS and MoWSNi, were synthesized to be used as a catalyst in hydrodesulfurization reactions. The mixed oxide mesoporous nanostructured MoO3 -WO3 with an Mo:W atomic ratio of 1:1 was used as the precursor. The first catalyst was prepared by impregnating nickel in the oxide precursor and then subsequent sulfiding with an H2S/H2 mix at 400 degrees C for 2 hours. The second catalyst was prepared by sulfiding the precursor and then impregnating the nickel, and finally reducing the material with a H2/N2 at 350 degrees C. In both catalysts the Mo:W:Ni atomic ratio was maintained at 1:1:0.5. The materials obtained were characterized by physical adsorption of nitrogen, X-ray diffraction, scanning electron microscopy, transmission electron microscopy. Furthermore, the materials obtained were evaluated by a dibenzothiophene hydrodesulfuration reaction. The diffraction patterns show that both materials are polycrystalline and mainly of MoS2 and WS2 phases.

Synthesis and characterization of porous Mo-W oxide nanostructures.

The present study reports the synthesis method, microstructure characterization, and thermal stability of nanostructured porous mixed oxide (MoO3-WO3) at 550 and 900 degrees C of annealing. The material was synthesized using a hydrothermal method. The precursor was prepared by aqueous solution using ammonium heptamolibdate and ammonium metatungstate, with an atomic ratio of Mo/W = 1. The pH was adjusted to 5, and then the solution was transferred to a teflon-lined stainless steel autoclave and heated at 200 degrees C for 48 h. The resultant material was washed using deionized water. The specific surface area, morphology, composition, and microstructure before and after annealing were studied by N2 physisorption, scanning electron microscopy (SEM), analytical transmission electron microscopy (TEM), and X-Ray diffraction (XRD). The initial synthesized materials showed low crystallinity and high specific surface area around (141 m2/g). After thermal annealing the material showed higher crystallinity and diminished its specific surface area drastically.

Nickel as a chemical modifier for sensitivity enhancement and fast atomization processes in electrothermal atomic absorption spectrometric determination of cadmium in biological and environmental samples.

A systematic study of the efficiency of protons, Ni, Pd and Th as chemical modifiers for the determination of cadmium by electrothermal atomic absorption spectrometry (ETAAS) using fast temperature programs was made for platform atomization. A comparison was made in terms of the salt type, absorbance-time profiles and elimination of the sodium chloride interference. The results were adapted to develop a method for the ETAAS determination of cadmium in biological and environmental samples. The highest sensitivity to determine cadmium in biological and environmental samples was obtained using nickel (together with protons) as a chemical modifier. The accuracy of the method was tested by the determination of cadmium in different certified reference materials. The best detection limit and the characteristic mass of Cd were found to be 0.03 ng mL(-1) and 0.35 pg, respectively.

Speciation of selenite and selenate using living bacteria.

In this work, a reliable method is described for speciation of soluble inorganic selenium ions, Se(IV) and Se(VI), which combines an uptake process by using living bacterial cells and electrothermal atomic absorption spectrometry (ETAAS). A selective retention of either Se(IV) or Se(IV) plus Se(VI) can be carried out by using the uptake system made up of either Pseudomonas putida or Escherichia coli strains cultivated in a culture medium based on glucose (P. putida) and glucose plus dipotassium phosphate (E. coli) mixed together with the original sample solution containing the selenium species. Discrimination between inorganic selenium species is possible by combining the optimization of the bacterial cell, the growth conditions and the relative rates of their retention from the sample. In the general procedure, an equilibrium between the analyte in the solution and the uptake system is allowed to be established, and then the concentration of selenium is determined directly in the biomass by slurry sampling ETAAS. Nonetheless, a theoretical model is proposed to describe the retention process by the living bacterial cells, which also provides a feasible quantification of the extraction process before the adsorption equilibrium is reached and whenever the agitation conditions and the sampling time are under control. The detection limits for the inorganic selenium species at the best retention conditions are of 5.7 ng Se(IV) ml(-1) for P. putida and 6.1 ng Se(IV) ml(-1) and 6.3 ng Se(VI) ml(-1) for E. coli. The relative standard deviations of the adsorption/determination process are 2.9-6.3%.

A thermodynamic approach to the binding mechanisms of cefotaxime to serum albumins.

The interaction between cefotaxime and the serum albumin of several mammalian species (swine, rabbits, and sheep) at the albumin concentration of 5 x 10(-5) M was studied. Ultrafiltration and spectrophotometric determination of the free antibiotic in the filtrate were used. Binding percentages were determined, and the binding constants and number of sites at various temperatures were calculated. An increase in binding constants, especially in sheep albumin, and an increase in the number of sites from two to three were observed when compared to the results obtained at the physiological albumin concentration. The thermodynamic parameters of interaction varied between the following values: change in Gibbs energy, between -5.7 and -6.4 kcal.mol-1; change in enthalpy, between -6.7 and -9.6 kcal.mol-1; and change in entropy, between -3.1 and -11.2 entropy units. The binding constants increased considerably as the ionic strength of the solution decreased although the number of binding sites remained unchanged. These results indicate the existence of ionic and hydrogen bonds. The possibility of a small contribution from hydrophobic bonds cannot be ruled out.

Possible biotransformation mechanism of 3-aminopropionitrile by means of free radicals.

The possible role of free radicals in the transformation of 3-aminopropionitrile giving rise to the liberation of cyanide was studied. Rat liver homogenates were cellularly fractionated. It was confirmed that the transformation occurred mainly in the microsomal fraction. The different isozyme forms of cytochrome P-450 were then partially purified and their velocity and affinity constants determined. It could be deduced that the cyanide-forming activity was mainly due to the LM3C cytochrome form. Dimethylsulfoxide was a potent competitive transformation inhibitor while mannitol was a moderate one. An OH radical generator inorganic system was also shown to liberate cyanide from 3-aminopropionitrile. In view of these results, a transformation mechanism of 3-aminopropionitrile by means of OH free radicals is suggested with the formation of cyanide anion in a cell-free organic system as well as in the microsomal fraction of rat liver.

The interaction of cefotaxime with the serum albumin of several mammalian species.

1. The interaction of cefotaxime with the serum albumin of several mammalian species; horses, swine, sheep, dogs and rabbits, was studied comparatively. The technique of ultrafiltration and spectrophotometric determination of the free antibiotic in the filtrate was used. 2. Binding percentages, which vary according to the species studied, were found to be higher in swine and rabbit albumins (between 92 and 81%) and lower for sheep, dog and horse albumins (between 67 and 52%). 3. The number of binding sites is usually close to 2; in the case of the horse it is 2.43. The apparent binding constants are: swine, 1.61 x 10(4) M-1; rabbit, 1.19 x 10(4) M-1; sheep, 2.33 x 10(3) M-1; dog, 2.00 x 10(3) M-1; horse, 1.42 x 10(3) M-1. The Scatchard model was used for data analysis. 4. Possible consequences of this interaction regarding clinical use of cefotaxime on different species are discussed.

[Production of cyanide in the rat liver from 3-aminopropionitrile]. / Production de cyanure dans le foie de rat à partir de 3-aminopropionitrile.

CN- Production was investigated from a saturated mononitrile, 3-aminopropionitrile, in small liver pieces and liver homogenates. Results show that CN- production is a function of time and of the concentration of active ingredient, with a trend to saturation in both cases. Similarly, cell integrity is not required for the biotransformation of 3-aminopropionitrile to occur. Cofactors such as NADPH must be present to reach high level activities. The effect of free radicals scavengers such as mannitol and DMSO was also studied.