Low toxicity of magnetite-based modified bionanocomposites with potential application for wastewater treatment: Evaluation in a zebrafish animal model.

In recent years, the escalating concerns surrounding environmental pollution and the need for sustainable wastewater treatment solutions have underscored the significance of developing technologies that can efficiently treat wastewater while also reducing negative ecological effects. In this context, our study aims to contribute to the advancement of sustainable technologies for wastewater treatment, by investigating the effects that bare magnetite nanoparticles and those functionalized with the enzyme laccase could have in an aquatic animal, zebrafish, at various life cycle stages. Exposure to magnetite nanoparticles shows some effects on embryo hatching, survival rates, or larval behavior at higher concentrations. For both treatments, the hatching percentages were close to 80% compared to 93% for the control group. At the end of the observations in larvae, survival in all the evaluated groups was higher than 90%. Additionally, we evaluated the accumulation of nanoparticles in various stages of zebrafish. We found that, although there was accumulation during embryonic stages, it did not affect normal development or subsequent hatching. Iron levels in different organs such as gills, muscles, gastrointestinal tract, and brain were also evaluated in adults. Animals treated with a mix of food and nanoparticles at 10 µg/mL (Food group) presented a higher concentration of iron accumulation in muscle, gastrointestinal tract, and gills compared to the untreated control group. Although iron levels increased depending on the dose and exposure method applied, they were not statistically significant from the control groups. Our findings suggest that bionanocomposites evaluated here can be considered safe for removal of contaminants in wastewater without toxic effects or detrimental accumulation fish's health.

Sobrevida del cáncer glótico en estadio inicial en 4 centros hospitalarios de Uruguay / Survival of glottic cancer in the initial stage in 4 hospital centers in Uruguay / Sobrevivência de câncer glótico em estágio inicial em 4 hospitais uruguaios

Introducción: El cáncer de laringe es el tumor maligno de mayor prevalencia en la Otorrinolaringología. La topografía glótica es la más frecuente en Uruguay y suele detectarse en estadios tempranos dada la manifestación precoz y sostenida de disfonía. El objetivo de este estudio es describir la sobrevida libre de enfermedad (SLE) y la sobrevida global (SG) de los pacientes con cáncer de laringe glótico en estadio T1N0M0 en 4 instituciones de Montevideo. Metodología: Se analizó de forma retrospectiva la SG y SLE de 55 pacientes diagnosticados con cáncer de glotis T1 entre los años 2009 y 2019. Para el cálculo de la sobrevida se utilizó el método de Kaplan-Meier. Se estudió además el efecto de variables pronósticas de interés sobre la SG mediante análisis univariado y multivariado. Resultados: En la muestra analizada la SG de los pacientes con cáncer glótico T1N0M0 fue como media de 7.706 años (IC 95% 6.63 - 8.78). A los 5 años, la SG fue de 77.5% (± 7%) y de 62% (± 9.8%) a los 10 años. La SLE para todos los pacientes correspondió al 74.6% (± 7.5%) y 63.1% (± 9.8%), a 5 y 10 años respectivamente. No se alcanzaron las medianas de SG ni de SLE para los grupos. Conclusiones: Los valores de SG y SLE medios obtenidos en nuestro medio son comparables a los valores reportados en la bibliografía internacional. No se alcanzó la mediana de SG ni de SLE, por lo que se puede afirmar que ésta enfermedad tiene, cuando se realiza el tratamiento adecuado, un buen pronóstico vital a los 10 años. Se requiere un seguimiento más largo para determinar las medianas de SG y SLE de los grupos en estudio.

Introduction: Laryngeal cancer is the most prevalent malignant tumor in Otorhinolaryngology. Glottic topography is the most frequent in Uruguay and is usually detected in early stages given the early and sustained manifestation of dysphonia. The objective of this study is to analyze disease-free survival (DFS) and overall survival (OS) of patients with stage T1N0M0 glottic laryngeal cancer at 4 institutions in Montevideo. Methodology: The mean OS and DFS of 55 patients diagnosed with T1 glottic cancer between 2009 and 2019 were retrospectively analyzed. Kaplan-Meier method was used to calculate survival. The prognostic effect of certain variables of interest on OS was also studied using univariate and multivariate analysis. Results: In this study, mean odds survival (OS) for T1N0M0 glottic cancer was 7.706 years (CI 95% 6.63 - 8.78). At 5 years, OS was 77.5% (± 7%) and at 10 years was 62% (± 9.8%). Disease free survival (DFS) was 74.6% ± (7.5%) at 5 years and 63.1% (± 9.8%), at 10 years. Median OS and DFS for the groups were not reached. Conclusions: OS and DFS in our medium is comparable to that reported in the international literature. The median OS and DFS were not reached, so it can be stated that this disease has, when appropriate treatment is performed, a good vital prognosis at 10 years. Longer follow-up is required to determine the median OS and DFS of the study groups.

Introdução: O câncer de laringe é o tumor maligno mais prevalente na Otorrinolaringologia. A topografia glótica é a mais frequente no Uruguai e geralmente é detectada em estágios iniciais devido à manifestação precoce e sustentada da disfonia. O objetivo deste estudo é analisar a sobrevida livre de doença (DFS) e a sobrevida global (OS) de pacientes com câncer de laringe glótico estágio T1N0M0 em 4 instituições em Montevidéu. Metodologia: Foram analisados retrospectivamente o OS e DFS de 55 pacientes diagnosticados com câncer glótico T1 entre 2009 e 2019. O método de Kaplan-Meier foi usado para calcular a sobrevida. Resultados: Na amostra, a sobrevida global (OS) do câncer glótico T1N0M0 foi em média de 7.706 anos (IC 95% 6,63 - 8,78). Aos 5 anos, a OS foi de 77,5% (± 7%) e 62% (± 9,8%) aos 10 anos. A DFS para todos os pacientes correspondeu a 74,6% (± 7,5%) e 63,1% (± 9,8%), aos 5 e 10 anos, respectivamente. As medianas de OS e DFS para os grupos não foram alcançadas. Conclusões: OS e DFS em nosso ambiente é comparável ao relatado na literatura internacional. As medianas de SG e SLD não foram alcançadas, pelo que se pode afirmar que esta doença apresenta, quando realizado tratamento adequado, um bom prognóstico vital aos 10 anos. É necessário um acompanhamento mais longo para determinar a mediana da SG e da SLD dos grupos de estudo.

Hipopotasemia no medicamentosa como biomarcador de nefropatía crónica temprana en adultos del sur de Honduras / Non-drug Hypokalemia as Biomarker of Early Chronic Kidney Disease in Adults from Southern Honduras

Introducción: La hipopotasemia es un trastorno hidroelectrolítico frecuente, asociado a enfermedades sistémicas y multifactoriales, cuya forma aguda puede complicarse y causar la muerte, pero en su presentación crónica puede ser un marcador de nefropatía. Objetivo: Caracterizar el perfil del paciente con hipopotasemia no medicamentosa atendidos de emergencia. Métodos: Se revisaron los registros de pacientes mayores de 18 años con diagnóstico de hipopotasemia, ingresados en el hospital en el período de junio 2018 a diciembre de 2019. Se colectaron datos demográficos, antecedentes médicos y evolución postratamiento. Se comparó con 108 pacientes sin hipopotasemia atendidos en el período de estudio. Resultados: Se encontraron 87 casos con edad media de 38,5 años. El 90,8 por ciento eran hombres menores de 50 años, de oficio agricultor (29,9 por ciento), con historia de exposición a plaguicidas y a altas temperaturas ambientales. La mayoría de ellos no tenía historia de enfermedad cardiometabólicas o renal previa. El 48,3 por ciento de todos los pacientes con hipopotasemia (n = 42) tenía creatinina mayor a 1,2 mg/dL y 63 por ciento tenía hiponatremia. La hipopotasemia fue moderada en 39 por ciento y severa en 12 por ciento, los hombres 4,7 veces más afectados que las mujeres. Respecto al grupo sin hipopotasemia y creatinina anormal, tenían mayor frecuencia de enfermedad crónica (92,5 por ciento versus 8 por ciento). Conclusiones: Se encontró hipopotasemia no medicamentosa en varones agricultores, sin enfermedad crónica, pero con datos de nefropatía temprana e hiponatremia, se sugirió la posibilidad de nefropatía mesoamericana. Debe establecerse una alerta epidemiológica regional y un programa de prevención y control(AU)

Introduction: Hypokalemia is a frequent hydroelectrolytic disorder, associated with systemic and multifactorial diseases, whose acute form can be complicated and cause death, but in its chronic presentation it can be a marker of nephropathy. Objective: To characterize the profile of the patient with non-drug hypokalemia seen in an emergency. Methods: The records of patients older than 18 years diagnosed with hypokalemia, admitted to the hospital from June 2018 to December 2019, were reviewed. Demographic data, medical history, and post-treatment evolution were collected. It was compared with 108 patients without hypokalemia seen in the same period. Results: 87 cases with mean age of 38.5 years were studied. 90.8% were men under 50 years of age, who worked as farmers (29.9percent), with history of exposure to pesticides and high ambient temperatures. Most of them had no history of previous cardiometabolic or renal disease. 48.3percent of all patients with hypokalemia (n = 42) had creatinine higher than 1.2 mg/dL and 63percent had hyponatremia. Hypokalemia was moderate in 39% and severe in 12percent, and it was found that men were affected 4.7 times more than women. Regarding the group without hypokalemia and abnormal creatinine, they had higher frequency of chronic disease (92.5percent versus 8percent). Conclusions: Non-drug hypokalemia was found in male farmers, without chronic disease, but with evidence of early nephropathy and hyponatremia. The possibility of Mesoamerican nephropathy was suggested. A regional epidemiological alert and a prevention and control program should be established(AU)

Magnetic Torus Microreactor as a Novel Device for Sample Treatment via Solid-Phase Microextraction Coupled to Graphite Furnace Atomic Absorption Spectroscopy: A Route for Arsenic Pre-Concentration.

This work studied the feasibility of using a novel microreactor based on torus geometry to carry out a sample pretreatment before its analysis by graphite furnace atomic absorption. The miniaturized retention of total arsenic was performed on the surface of a magnetic sorbent material consisting of 6 mg of magnetite (Fe3O4) confined in a very small space inside (20.1 µL) a polyacrylate device filling an internal lumen (inside space). Using this geometric design, a simulation theoretical study demonstrated a notable improvement in the analyte adsorption process on the solid extractant surface. Compared to single-layer geometries, the torus microreactor geometry brought on flow turbulence within the liquid along the curvatures inside the device channels, improving the efficiency of analyte-extractant contact and therefore leading to a high preconcentration factor. According to this design, the magnetic solid phase was held internally as a surface bed with the use of an 8 mm-diameter cylindric neodymium magnet, allowing the pass of a fixed volume of an arsenic aqueous standard solution. A preconcentration factor of up to 60 was found to reduce the typical "characteristic mass" (as sensitivity parameter) determined by direct measurement from 53.66 pg to 0.88 pg, showing an essential improvement in the arsenic signal sensitivity by absorption atomic spectrometry. This methodology emulates a miniaturized micro-solid-phase extraction system for flow-through water pretreatment samples in chemical analysis before coupling to techniques that employ reduced sample volumes, such as graphite furnace atomic absorption spectroscopy.

Use of slow atomization ramp in high resolution continuum source graphite furnace atomic absorption spectrometry for the simultaneous determination of Cd and Ni in slurry powdered chocolate samples.

A methodology for simultaneous (not sequential) determination of Cd and Ni in powder chocolate samples by high-resolution continuum source graphite furnace atomic absorption spectroscopy (HR-CS-GF-AAS) and slurry sample analysis was developed. Acid digestion of the samples was not necessary, considering the high total fat content of this type of matrix (above 10 %), and no apparent deterioration of the graphite tubes was even observed once these samples were subjected to analysis. Despite the volatilities of both elements are quite different, simultaneous quantification was achieved using a slow heating ramp atomization, covering a convenient and wide temperature gradient for Cd volatilization at low temperatures and subsequent atomization of Ni at elevated temperatures, using the same heating program without an apparent change in sensitivity. This slow heating ramp was essayed between 200 and 1500 °C·s-1 and optimized at 400 °C·s-1, achieving the simultaneous measuring of Cd in the principal line (228.8018 nm) and using a secondary for Ni (228.9984 nm). No stop events for sequential changes in wavelength or temperature additional steps were involved in the method and molecular spectral interferences overlapping the analyte signals were corrected appropriately by a pragmatic strategy taking advantage of the fine structure signals adjacent to analyte signals within the same spectrum recorded. Palladium matrix modifier and aqueous standards were used for the calibration and determination of both elements in the samples. The method accuracy was successfully confirmed using a reference material (NIST SRM 1573a). An improvement in the sensitivity of Ni was found using a greater number of pixels for signal integration, central and five adjacent pixels (CP ± 5), while a lengthening of the linear range of Cd was obtained by using an attenuated signal (±2) or using only one pixel (CP). The limits of detection were 0.027 µg g-1 and 0.22 µg g-1 for Cd and Ni respectively by this simple methodology using aqueous standards for calibration and the simultaneous determination of both elements in the same measurement. The respective limits of quantification for Cd and Ni were 0.090 and 0.72 µg g-1 and the relative standard deviations in samples (n = 5) were about 4-20% and 0.3-11% for Cd and Ni respectively. The optimized method was used for the determination of both elements in real samples purchased from retail supermarkets finding variable concentrations between 0.5 and 5.7 µg g-1 for Cd and 2.1-10.9 µg g-1 for Ni, comparable to levels reported in the literature referred to elsewhere in the world.

Functionalization and Evaluation of Inorganic Adsorbents for the Removal of Cadmium in Wastewater.

This study presents the feasibility of using various functionalized substrates, Fe3O4 nanoparticles (NPs) and Al2O3 spheres, for the removal of Cd from aqueous solution. To improve the materials' affinity to Cd, we explored four different surface modifications, namely (3-Aminopropyl) triethoxysilane (APTES), L-Cysteine (Cys) and 3-(triethoxysilyl) propylsuccinic anhydride (CAS). Particles were characterized by FTIR, FIB-SEM and DLS and studied for their ability to remove metal ions. Modified NPs with APTES proved to be effective for Cd removal with efficiencies of up to 94%, and retention ratios up to 0.49 mg of Cd per g of NPs. Batch adsorption experiments investigated the influence of pH, contact time, and adsorbent dose on Cd adsorption. Additionally, the recyclability of the adsorbent and its potential phytotoxicity and animal toxicity effects were explored. The Langmuir, Freundlich, pseudo-first-order and pseudo-second-order models were applied to describe the behavior of the Cd adsorption processes. The adsorption and desorption results showed that Fe3O4 NPs modified with APTES are promising low-cost platforms with low phytotoxicity for highly efficient heavy metal removal in wastewater.

Effects of control temperature, ablation time, and background tissue in radiofrequency ablation of osteoid osteoma: A computer modeling study.

To study the effects of the control temperature, ablation time, and the background tissue surrounding the tumor on the size of the ablation zone on radiofrequency ablation (RFA) of osteoid osteoma (OO). Finite element models of non-cooled temperature-controlled RFA of typical OOs were developed to determine the resulting ablation radius at control temperatures of 70, 80, and 90°C. Three different geometries were used, mimicking common cases of OO. The ablation radius was obtained by using the Arrhenius equation to determine cell viability. Ablation radii were larger for higher temperatures and also increased with time. All geometries and control temperatures tested had ablation radii larger than the tumor. The ablation radius developed rapidly in the first few minutes for all geometries and control temperatures tested, developing slowly towards the end of the ablation. Resistive heating and the temperature distribution showed differences depending on background tissue properties, resulting in differences in the ablation radius on each geometry. The ablation radius has a clear dependency not only on the properties of the tumor but also on the background tissue. Lower background tissue's electrical conductivity and blood perfusion rates seem to result in larger ablation zones. The differences observed between the different geometries suggest the need for patient-specific planning, as the anatomical variations could cause significantly different outcomes where models like the one here presented could help to guarantee safe and successful tumor ablations.

Short CRP for Anterior Canalithiasis: A New Maneuver Based on Simulation With a Biomechanical Model.

Introduction/Objective: Anterior canalithiasis is an uncommon and challenging diagnosis. This is due in part to the difficulty of defining the affected side, the extreme positioning required to carry out described therapeutic maneuvers, and the infrequent use of specific maneuvers. Our objective is to present a new treatment alternative for anterior canalithiasis which is based on the well-known canalith repositioning procedure (CRP) described by Epley and which is used routinely in the treatment of both posterior and anterior canalithiasis. Analysis of the standard CRP for anterior canalithiasis with a biomechanical model validates that this new maneuver is an enhanced treatment option for anterior canalithiasis. We call the new maneuver the "short CRP." Methods: A previously published 3D biomechanical model of the human labyrinths for the study of BPPV was used to analyze the conventional CRP in the treatment of anterior canalithiasis. The expected position of free otoliths near the anterior ampulla of the anterior semicircular duct was followed while recreating the sequential positions of the CRP. Although the standard CRP was possibly effective, certain enhancements were evident that could increase successful repositioning. These enhancements were incorporated into the modification of the CRP presented here as the "short CRP" for anterior canalithiasis. Results: The traditional CRP used for posterior canalithiasis can also be used for anterior canalithiasis. Although in the traditional CRP the head hangs 30° below horizontal, our simulation shows that a 40° head-hang below horizontal is an enhancement and may ensure progression of anterior otolith debris. Elimination of Position 4 of the classic CRP, in which the face is turned 45° toward the floor, was also seen as an enhancement as this position is predicted to cause retrograde movement of otoliths back into the anterior canal if the patient tucks the chin in position 4 or when sitting up. Conclusion: A modification of the CRP called the "short CRP" can be used to treat anterior canalithiasis. Model analysis predicts possible increased efficacy over the standard CRP. Model analysis of existing BPPV treatments is a valuable exercise for examination and can lead to realistic enhancements in patient care.

Radiofrequency ablation of atypical cartilaginous tumors in long bones: a retrospective study.

Purpose: To determine the size of the ablation zone after radiofrequency ablation (RFA) of atypical cartilaginous bone tumors (ACT) using temperature-controlled 20 and 30 mm RFA straight non-cooled electrodes.Materials and methods: Sixteen patients with ACT in their long bones, who had undergone a single-session single-application CT-guided temperature-controlled RFA, were included retrospectively in the study. Tumors with a diameter of 10-25 mm were treated with 20 mm electrodes (n = 10), and tumors of 25-35 mm, with 30 mm electrodes (n = 6). The ablated zone was measured after three months on MRI images.Results: All the tumors were within the ablated zone on the 3-month follow-up MRI scan. The mean ablation time with the electrode, at a target temperature of 90 °C, was 7.6 minutes (range 6-10). The median of the largest ablation diameters, on applying the 20 and 30 mm electrodes, were 42 mm (IQR 8.5, range 30-51 mm) and 44.5 mm (IQR 4.5, range 42-63 mm), respectively.Conclusions: All the retrospectively viewed tumors in the long bones of ACT patients treated with RFA were completely ablated. The ablation zone diameters in the bones were larger than expected, when compared to other tissues, such as the liver.

High Efficiency Mercury Sorption by Dead Biomass of Lysinibacillus Sphaericus-New Insights into the Treatment of Contaminated Water.

Mercury (Hg) is a toxic metal frequently used in illegal and artisanal extraction of gold and silver which makes it a cause of environmental poisoning. Since biosorption of other heavy metals has been reported for several Lysinibacillus sphaericus strains, this study investigates Hg removal. Three L. sphaericus strains previously reported as metal tolerant (CBAM5, Ot4b31, and III(3)7) were assessed with mercury chloride (HgCl2). Bacteria were characterized by scanning electron microscopy coupled with energy dispersive spectroscopy (EDS-SEM). Sorption was evaluated in live and dead bacterial biomass by free and immobilized cells assays. Hg quantification was achieved through spectrophotometry at 508 nm by reaction of Hg supernatants with dithizone prepared in Triton X-114 and by graphite furnace atomic absorption spectroscopy (GF-AAS). Bacteria grew up to 60 ppm of HgCl2. Non-immobilized dead cell mixture of strains III(3)7 and Ot4b31 showed a maximum sorption efficiency of 28.4 µg Hg/mg bacteria during the first 5 min of contact with HgCl2, removing over 95% of Hg. This process was escalated in a semi-batch bubbling fluidized bed reactor (BFB) using rice husk as the immobilization matrix leading to a similar level of efficiency. EDS-SEM analysis showed that all strains can adsorb Hg as particles of nanometric scale that can be related to the presence of S-layer metal binding proteins as shown in previous studies. These results suggest that L. sphaericus could be used as a novel biological method of mercury removal from polluted wastewater.

Chemical profiling of infusions and decoctions of Helichrysum italicum subsp. picardii by UHPLC-PDA-MS and in vitro biological activities comparatively with green tea (Camellia sinensis) and rooibos tisane (Aspalathus linearis).

Several medicinal plants are currently used by the food industry as functional additives, for example botanical extracts in herbal drinks. Moreover, the scientific community has recently begun focusing on halophytes as sources of functional beverages. Helichrysum italicum subsp. picardii (everlasting) is an aromatic halophyte common in southern Europe frequently used as spice and in traditional medicine. In this context, this work explored for the first time H. italicum subsp. picardii as a potential source of innovative herbal beverages with potential health promoting properties. For that purpose, infusions and decoctions were prepared from roots, vegetative aerial-organs (stems and leaves) and flowers and evaluated for in vitro antioxidant and anti-diabetic activities. Samples were also assessed for toxicity in different mammalian cell lines and chemically characterized by spectrophotometric methods and ultra-high performance liquid chromatography-photodiode array-mass-spectrometry (UHPLC-PDA-MS). Results were expressed relating to 'a cup-of-tea' and compared with those obtained with green tea (Camellia sinensis) and rooibos tisane (Aspalathus linearis). Tisanes from the everlasting's above-ground organs, particularly flowers, have high polyphenolic content and several phenolics were identified; the main compounds were chlorogenic and quinic acids, dicaffeoylquinic-acid isomers and gnaphaliin-A. The antioxidant activity of beverages from the everlasting's above-ground organs matched or surpassed that of green tea and rooibos. Its anti-diabetic activity was moderate and toxicity low. Overall, our results suggest that the everlasting is a potential source of innovative and functional herbal beverages.

Genetic variation of 17 STR loci in a Mexican Mestizo population from Mexico City.

Genetic data from 17 autosomal short tandem repeat (STR) loci found in the Powerplex® ESX 17 System (Promega, Madison, WI, USA) was evaluated in 162 unrelated Mexican Mestizo individuals from Mexico City. Allele frequencies and forensic parameters were estimated for the 17 STRs. All loci analyzed were in Hardy-Weinberg equilibrium in the studied population and showed not any signs of linkage between loci. The combined power of discrimination and the power of exclusion for the 16 aSTRs studied were 1-2.56409·10-19 and 99.999938 %, respectively. Genetic distances reveal a close relationship within different populations of Mexican Mestizos. The obtained data might be useful for population genetics research and for individual identification and paternity testing in forensic science.

NDEx, the Network Data Exchange.

Networks are a powerful and flexible methodology for expressing biological knowledge for computation and communication. Network-encoded information can include systematic screens for molecular interactions, biological relationships curated from literature, and outputs from analysis of Big Data. NDEx, the Network Data Exchange (www.ndexbio.org), is an online commons where scientists can upload, share, and publicly distribute networks. Networks in NDEx receive globally unique accession IDs and can be stored for private use, shared in pre-publication collaboration, or released for public access. Standard and novel data formats are accommodated in a flexible storage model. Organizations can use NDEx as a distribution channel for networks they generate or curate. Developers of bioinformatic applications can store and query NDEx networks via a common programmatic interface. NDEx helps expand the role of networks in scientific discourse and facilitates the integration of networks as data in publications. It is a step towards an ecosystem in which networks bearing data, hypotheses, and findings flow easily between scientists.

Hollow fiber based liquid-phase microextraction for the determination of mercury traces in water samples by electrothermal atomic absorption spectrometry.

A three-phase liquid microextraction procedure for the determination of mercury at low concentrations is discussed. To the aqueous sample placed at pH 7 by means of a phosphate buffer, 0.002% (m/v) 1-(2-pyridylazo)-2-naphthol (PAN) is incorporated, and the mixture submitted to microextraction with a hollow-fiber impregnated with toluene and whose lumen contains a 0.05 mol L(-1) ammonium iodide solution. The final measurement of the extract is carried out by electrothermal atomic absorption spectrometry (300°C and 1100°C for the calcination and atomization temperatures, respectively). The pyrolytic graphite atomizer is coated electrolytically with palladium. An enrichment factor of 270, which results in a 0.06 µg L(-1) mercury for the detection limit is obtained. The relative standard deviation at the 1 µg L(-1) mercury level is 3.2% (n=5). The reliability of the procedure is verified by analyzing waters as well as six certified reference materials.

Ultrasound-assisted emulsification microextraction coupled with gas chromatography-mass spectrometry using the Taguchi design method for bisphenol migration studies from thermal printer paper, toys and baby utensils.

The optimization of a clean procedure based on ultrasound-assisted emulsification liquid-liquid microextraction for the sensitive determination of four bisphenols is presented. The miniaturized technique was coupled with gas chromatography-mass spectrometry after derivatization by in situ acetylation. The Taguchi experimental method, an orthogonal array design, was applied to find the optimal combination of seven factors (each factor at three levels) influencing the emulsification, extraction and collection efficiency, namely acetic anhydride volume, sodium phosphate concentration, carbon tetrachloride volume, aqueous sample volume, sodium chloride concentration and ultrasound power and application time. A second factorial design was applied with four factors and five levels for each factor, 25 experiments being performed in this instance. The matrix effect was evaluated, and it was concluded that sample quantification can be done by calibration with aqueous standards. The detection limits ranged from 0.01 to 0.03 ng mL(-1) depending on the compound. The environmentally friendly sample pretreatment procedure was applied to study the migration of the bisphenols from different types of samples: thermal printer paper, compact discs, digital versatile discs, small tight-fitting waistcoats, baby's bottles, baby bottle nipples of different materials and children's toys.

Use of carbon nanotubes and electrothermal atomic absorption spectrometry for the speciation of very low amounts of arsenic and antimony in waters.

A procedure for the determination of inorganic arsenic (III, V) and antimony (III, V) in water samples by using a miniaturized solid-phase extraction with carbon nanotubes followed by electrothermal atomic absorption measurement is proposed. The trivalent species are first complexed with ammonium pyrrolidinedithiocarbamate, next retained in a mini-column containing nanotubes and then eluted by means of a plug of an ammonia solution. The atomizer is impregnated with a tungsten salt which acts as an effective chemical modifier during the heating cycle. Total inorganic arsenic and antimony are determined after the reduction of the pentavalent forms with an ammonium iodide solution. Pentavalent arsenic and antimony are calculated by difference. When using 50 mL sample solutions, the limits of detection are 0.02 and 0.05 µg L(-1) for As and Sb, respectively, and the enrichment factor is 250. The relative standard deviations calculated for five determinations at the 1 µg L(-1) level are below 4%.

3D didactic model and useful guide of the semicircular conducts.

UNLABELLED: Knowledge of the anatomy and physiology of the semicircular canals and their central pathways is essential for the diagnosis of vestibular pathology. This 3 dimensional (3D) scheme of the Semicircular Canals (SSCC) is a teaching tool and a useful reference guide for rapid consultation. MATERIAL AND METHODS: A multicolored cardboard model is accompanied by a user manual which provides a thorough description of the tool for the most common vestibular diseases. RESULTS: Although results cannot be quantitatively assessed, the model has been well received at several Latin American scientific conferences. The model is often understood with verbal instruction only; nevertheless, a printed user manual is included. CONCLUSIONS: This 3 dimensional (3D) model of the Semicircular Canals (SSCC) is a practical, low cost tool for use in private and academic settings.

3D didactic model and useful guide of the semicircular conducts / Modelo didático 3D e guia útil dos canais semicirculares

Knowledge of the anatomy and physiology of the semicircular canals and their central pathways is essential for the diagnosis of vestibular pathology. This 3 dimensional (3D) scheme of the Semicircular Canals (SSCC) is a teaching tool and a useful reference guide for rapid consultation. MATERIAL AND METHODS: A multicolored cardboard model is accompanied by a user manual which provides a thorough description of the tool for the most common vestibular diseases. RESULTS: Although results cannot be quantitatively assessed, the model has been well received at several Latin American scientific conferences. The model is often understood with verbal instruction only; nevertheless, a printed user manual is included. CONCLUSIONS: This 3 dimensional (3D) model of the Semicircular Canals (SSCC) is a practical, low cost tool for use in private and academic settings.

A identificação de determinadas afecções vestibulares exige conhecimento prévio sobre anatomia e fisiologia dos canais semicirculares (CSC) e de suas conexões centrais, que apresentam complexidade anatômica tridimensional e funcional. OBJETIVO: Propor um modelo anatômico e funcional dos CSC, em 3 dimensões (3D), para servir como uma ferramenta didática e um guia útil de consulta rápida. MATERIAL E MÉTODOS: O modelo é projetado em cartão, com impressão em cores diferentes, acompanhados de um texto explicativo de 22 folhas, que detalha sua descrição topográfica, descritiva e sua utilização com base em exemplos das doenças vestibulares mais frequentes. RESULTADOS: Embora os resultados não possam ser avaliados numericamente, este modelo já foi compreendido por diversos especialistas e tem sido bastante utilizado por eles. Além disso, o produto deste trabalho já foi apresentado em diferentes eventos científicos latino-americanos com excelente aceitação. CONCLUSÃO: Trata-se de ferramenta útil e de baixo custo para o ensino, a prática clínica diária em otoneurologia.

[Thyroid function alteration in patients with radiation therapy of the neck]. / Alteración de la función tiroidea en los pacientes en los que se realizó radioterapia cervical.

INTRODUCTION: The aim of this study is to determine whether the incidence of hypothyroidism in patients with Head and Neck Cancer who have undergone neck radiotherapy justifies the inclusion of thyroid function monitoring in the pre-operative and follow-up evaluation protocols. MATERIAL AND METHODS: A retrospective study was conducted with all the patients seen in the Oncology Section of the Otorhinolaryngology Department in the "Hospital de Clínicas", Montevideo, Uruguay, from January 1970 to May 2008. A total of 550 case records were analyzed. Of the 550 patients, 188 were excluded due to the fact they had not received radiotherapy as part of their treatment and 362 were included in the study. Of these, 55 patients had thyroid stimulating hormone (TSH) level determination after treatment with radiation therapy. Hypothyroidism was defined as a TSH value greater than or equal to 4.5 mIU/L, regardless of whether or not any symptoms were presented. RESULTS: 36.4% of the patients were diagnosed as having clinical or sub-clinical hypothyroidism. The type of treatment carried out, particularly whether or not surgical resection was performed, was found to be the most significant predictive factor for the development of hypothyroidism (P=0.054). CONCLUSION: Monitoring of the thyroid function on a six-month or annual basis, at least during the first 5 post-treatment years, has to be included in the follow-up and control protocols of every patient undergoing neck RT, and patients with TSH values over 4.5 mIU/L should be referred to the endocrinologist for hormone replacement, whether they present symptoms or not.

Alteración de la función tiroidea en los pacientes en los que se realizó radioterapia cervical / Thyroid function alteration in patients with radiation therapy of the neck

Introducción: El propósito de este trabajo es determinar si la incidencia de hipotiroidismo en los pacientes con cáncer de cabeza y cuello en los que se realizó radioterapia cervical justifica la inclusión de la monitorización de la función tiroidea en los protocolos de valoración preoperatoria y de seguimiento. Material y métodos: Se realizó un estudio retrospectivo de todos los pacientes atendidos en la Sección Oncológica del Departamento de Otorrinolaringología del Hospital de Clínicas Montevideo, Uruguay, desde enero de 1970 a mayo de 2008. Se revisó un total de 550 historias clínicas. Del total de 550 pacientes, se excluyeron 188 pacientes dado que no habían recibido radioterapia (RT) como parte del tratamiento, y 362 fueron incluidos en el estudio. Cincuenta y cinco pacientes tenían dosificación de hormona estimulante de la tiroides (TSH) postratamiento con RT. El hipotiroidismo fue definido como un valor de TSH mayor o igual a 4,5mU/l, independientemente de si presentaba o no síntomas. Resultados: Se encontró un 36,4% de pacientes con hipotiroidismo clínico o subclínico. Se determinó que la modalidad de tratamiento efectuado, en especial si se realizó resección quirúrgica o no, es el factor predictivo más significativo de desarrollo de hipotiroidismo (p = 0,054). Conclusión: La monitorización de la función tiroidea debe ser incluida en los protocolos de seguimiento y control de todos los pacientes en los que se realice RT de cuello, semestral o anualmente, por lo menos durante los primeros 5 años postratamiento, y derivar al endocrinólogo para el reemplazo hormonal a los pacientes con TSH mayores a 4,5mU/l, tengan o no síntomas (AU)

Introduction: The aim of this study is to determine whether the incidence of hypothyroidism in patients with Head and Neck Cancer who have undergone neck radiotherapy justifies the inclusion of thyroid function monitoring in the pre-operative and follow-up evaluation protocols. Material and methods: A retrospective study was conducted with all the patients seen in the Oncology Section of the Otorhinolaryngology Department in the Hospital de Clínicas , Montevideo, Uruguay, from January 1970 to May 2008. A total of 550 case records were analyzed. Of the 550 patients, 188 were excluded due to the fact they had not received radiotherapy as part of their treatment and 362 were included in the study. Of these, 55 patients had thyroid stimulating hormone (TSH) level determination after treatment with radiation therapy. Hypothyroidism was defined as a TSH value greater than or equal to 4.5mIU/L, regardless of whether or not any symptoms were presented. Results: 36.4% of the patients were diagnosed as having clinical or sub-clinical hypothyroidism. The type of treatment carried out, particularly whether or not surgical resection was performed, was found to be the most significant predictive factor for the development of hypothyroidism (P=0.054). Conclusion: Monitoring of the thyroid function on a six-month or annual basis, at least during the first 5 post-treatment years, has to be included in the follow-up and control protocols of every patient undergoing neck RT, and patients with TSH values over 4.5mIU/L should be referred to the endocrinologist for hormone replacement, whether they present symptoms or not (AU)