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1.
Talanta ; 274: 125939, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38547838

RESUMEN

A new simple, fast and environmentally friendly deep eutectic solvent based dispersive liquid-liquid microextraction (DES-based DLLME) methodology assisted by vortex is presented for the separation and preconcentration of three elements (i.e., Fe, Cu and Pb) from edible oil samples (i.e., soybean, sunflower, rapeseed, sesame, and olive oil) prior to the determination by microwave-induced plasma optical emission spectrometry (MIP-OES). The deep eutectic solvent selected as extractant (i.e., choline chloride and ethylene glycol, 1:2) is synthesized and characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H NMR) and differential scanning calorimetry (DSC), and the extraction conditions are optimized by a two steps experimental design. Under the optimum extraction conditions (i.e., diluted sample weight: 8.6 g; DES volume: 100 µL; extraction time: 1 min; centrifugation time and speed: 3 min and 3000 rpm; and dispersion system: vortex) the analytical method presents excellent linearity (i.e., R2 values higher than 0.99) in the range 10-500 µg kg-1, repeatability (i.e., CV values lower than 9.2%), and limits of detection (LOD) values of 3, 2 and 0.7 µg kg-1 for Pb, Fe and Cu, respectively. None of the analytes displayed amounts over the upper limit permitted by law, and recovery values of all analytes evaluated in the different samples using external standard calibration were close to 100%, which excludes significant matrix effects. Finally, AGREEprep metric has been used to evaluate the method greenness (final score of 0.47) and it has been compared successfully with previous publications for the same type of analytes and matrices.

2.
Sci Rep ; 13(1): 19389, 2023 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-37938669

RESUMEN

In recent years, several nanocarrier synthesis methods have been developed. In cancer therapy, the use of smart nanocarriers is of interest. Smart nanocarriers respond to their environment and can release their cargo in a controlled manner under the action of internal or external stimuli. In this work, we report on the development of an aerosol-assisted method for the synthesis of curcumin-loaded chitosan/alginate-based polymeric nanocarrier (CurNCs). A custom-fabricated multi-nebulizer system was utilized for the synthesis of CurNCs. The developed system comprises three main parts a sprayer, an electric heater tunnel, and a collector. Curcumin and chitosan solutions were sprayed using a pneumatic multinebulizer into the electric heater tunnel to form chitosan-curcumin assemblies. Then, the aerosol was guided into the collector solution containing sodium alginate and tri-poly phosphate aqueous solution for further cross-linkage. The synthesized CurNCs were characterized using TEM, DLS, and FTIR techniques. The TEM size of the nanoparticles was 8.62 ± 2.25 nm. The release experiments revealed that the nanocarrier is sensitive to the environment pH as more curcumin is released at acidic pH values (as is the case for cancerous tissues) compared to physiological pH. The curcumin content of the nanocarrier was 77.27 mg g-1 with a drug loading efficiency of 62%. The in-vitro cytotoxicity of the synthesized nanocarrier was evaluated against the MCF7 breast cancer cell line. The IC50 concentrations for CurNCs and curcumin were obtained as 14.86 and 16.45 mg mL-1, respectively. The results showed that while the empty nanocarrier shows non-significant cytotoxicity, the CurNCs impact the cell culture and cause prolonged cell deaths. Overall, pH-responsive curcumin polymeric nanocarrier was synthesized using a custom fabricated aerosol-based method. The method enabled fast and feasible synthesis of the nanocarrier with high efficiency.


Asunto(s)
Antineoplásicos , Quitosano , Curcumina , Curcumina/farmacología , Aerosoles , Alginatos , Polímeros , Antineoplásicos/farmacología , Concentración de Iones de Hidrógeno
3.
Rev Med Inst Mex Seguro Soc ; 61(5): 691-694, 2023 Sep 04.
Artículo en Español | MEDLINE | ID: mdl-37773183

RESUMEN

Background: Succinyl-CoA:3 oxoacid CoA transferase deficiency (SCOTD) is a rare autosomal recessive disease, characterized by altered utilization of ketone bodies, with acute episodes of ketoacidosis. Clinical case: It is presented the case of a patient with SCOTD, with a first atypical episode accompanied by hyperglycemia, with 4 subsequent episodes with classic manifestations of the disease, presenting with a biochemical pattern of permanent ketonuria with marked elevation of ketone bodies (acetoacetate, 3 beta-hydroxybutyrate) in the study of urinary organic acids by gas chromatography and mass spectrometry, together with the clinical picture granting the diagnosis. It was started a maintenance therapy with a characteristic feeding plan; it was shown an adequate response to treatment, and the absence of permanent ketosis was surmised. Conclusion: Being a rare disease, the categorization of these patients as diabetic ketoacidosis is frequent. The clinical and biochemical characteristics with ketosis or persistent ketonuria should be analyzed very carefully, especially in patients presenting with hyperglycemia, which is an atypical manifestation of the disease, in order to make an early diagnosis and treatment, positively impacting the prognosis of patients.


Introducción: la deficiencia de succinil-CoA acetoacetato transferasa (SCOT) es una enfermedad rara, autosómica recesiva, caracterizada por alteración en la utilización de cuerpos cetónicos, con episodios agudos de cetoacidosis. Caso clínico: se presenta el caso de un paciente con deficiencia de SCOT, con un primer episodio atípico acompañado con hiperglucemia, con 4 episodios posteriores con manifestaciones clásicas de la enfermedad, que presentó patrón bioquímico de cetonuria permanente con marcada elevación de cuerpos cetónicos (acetoacetato, 3 beta-hidroxibutirato) en estudio de ácidos orgánicos urinarios por cromatografía de gases y espectrometría de masas, aunado a cuadro clínico que otorgó el diagnóstico. Se inició terapia de mantenimiento con plan de alimentación característico; se demostró una adecuada respuesta al tratamiento, y se infirió una ausencia de cetosis permanente. Conclusiones: al ser una enfermedad rara, la categorización de estos pacientes como cetoacidosis diabética es frecuente. Se deben analizar de forma muy minuciosa las características clínicas y bioquímicas con cetosis o cetonuria persistente, sobre todo en pacientes que se presenten con hiperglucemia, que es una manifestación atípica de la enfermedad, para realizar un diagnóstico y tratamiento temprano que impacte de forma positiva el pronóstico de los pacientes.


Asunto(s)
Hiperglucemia , Cetosis , Humanos , Coenzima A Transferasas , Cuerpos Cetónicos , Cetosis/etiología , Ácido 3-Hidroxibutírico/análisis , Hiperglucemia/complicaciones
4.
Anal Bioanal Chem ; 415(18): 4435-4444, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36872410

RESUMEN

A new natural deep eutectic solvent (NADES)-based analytical method for mercury speciation in water samples is presented. A NADES (i.e., decanoic acid:DL-menthol in a molar ratio of 1:2) is used as an environmentally friendly extractant for separation and preconcentration using dispersive liquid-liquid microextraction before LC-UV-Vis. Under optimal extraction conditions (i.e., NADES volume, 50 µL; sample pH, 12; volume of the complexing agent, 100 µL; extraction time, 3 min; centrifugation speed, 3000 rpm; and centrifugation time, 3 min), the limit of detection values were 0.9 µg L-1 for the organomercurial species and 3 µg L-1 for Hg2+, which had a slightly higher value. The relative standard deviation (RSD, n = 6) has been evaluated at two concentration levels (25 and 50 µg L-1) obtaining values for all the mercury complexes within the range of 6-12% and 8-12%, respectively. The trueness of the methodology has been evaluated using five real water samples from four different sources (i.e., tap, river, lake, and wastewater). The recovery tests have been performed in triplicate obtaining relative recoveries between 75 and 118%, with RSD (n = 3) between 1 and 19%, for all the mercury complexes in surface water samples. However, wastewater sample showed a significant matrix effect (recoveries ranged between 45 and 110%), probably due to the high amount of organic matter. Finally, the greenness of the method has also been evaluated by the analytical greenness metric for sample preparation (i.e., AGREEprep).


Asunto(s)
Microextracción en Fase Líquida , Mercurio , Contaminantes Químicos del Agua , Mercurio/análisis , Solventes/química , Disolventes Eutécticos Profundos , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Microextracción en Fase Líquida/métodos , Agua/química , Límite de Detección
5.
Sensors (Basel) ; 22(22)2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36433439

RESUMEN

Two analytical methods based on miniaturized electrochemical sensors, voltammetric and amperometric sensors, have been developed for the determination of 6-methyl-2-thiouracil (MTU) in meat consumption samples (beef liver and foie). A multivariate approach has been considered to optimize the experimental procedure including extraction and electrochemical detection. Under optimal conditions and at a typical working potential of 1.55 V (vs Ag pseudo-reference electrode), response is linear in the range 0 to 20 µg L−1 MTU concentration range. The empirical limit of detection is 0.13 µg L−1, lower than the maximum concentration established by legislation. The electrochemical methods have been used to analyze MTU-spiked meat samples, and recovery values varying between 85 and 95% with coefficients of variation <30%. The analytical methods developed with the miniaturized electrochemical sensors can successfully determine the concentration of MTU in real meat samples with high accuracy, being the results obtained similar to those provided by other methods such as UV-Vis spectrophotometry. Finally, the degree of sustainability of the electrochemical sensors-based developed method has been quantified by means of the Analytical Eco-Scale.


Asunto(s)
Técnicas Electroquímicas , Metiltiouracilo , Bovinos , Animales , Técnicas Electroquímicas/métodos , Electrodos , Carne
6.
Artículo en Inglés | MEDLINE | ID: mdl-34948623

RESUMEN

This case study investigates the exposure of 119 Spanish women of reproductive age to 5 essential (Co, Cu, Mn, V, Zn) and 10 toxic (Ba, Be, Cs, Ni, Pb, Pt, Sb, Th, Al, U) elements and assesses their risk. The essential elements (Co, Cu, Mn, V, and Zn) showed average concentrations (GM: geometric mean) of 0.8, 35, 0.5, 0.2, and 347 µg/L, respectively. Five of the toxic elements (Ba, Cs, Ni, Al, U) exhibited detection frequencies of 100%. The GM concentrations of the novel toxic elements were 12 µg/L (Al), 0.01 µg/L (Pt), 0.02 µg/L (U), 0.12 µg/L (Th), 0.009 µg/L (Be) and 4 µg/L (Cs). The urine analysis was combined with a survey to assess any variations between subgroups and potential predictors of exposure to elements in the female population. Significant differences were obtained between the rural and urban areas studied for the toxic element Cs, with higher levels found in mothers living in urban areas. In relation to diet, statistically significantly higher levels of essential (Cu) and toxic (Ba) elements were detected in women with a high consumption of fish, while mothers who consumed a large quantity of legumes presented higher levels of the toxic element Ni (p = 0.0134). In a risk-assessment context, hazard quotients (HQs) greater than 1 were only observed for the essential elements Zn and Cu in P95. No deficiency was found regarding the only essential element for which a biomonitoring equivalent for nutritional deficit is available (Zn). For the less-studied toxic elements (Al, Pt, U, Th, Be, and Cs), HQs were lower than 1, and thus, the health risk due to exposure to these elements is expected to be low for the female population under study.


Asunto(s)
Monitoreo Biológico , Oligoelementos , Animales , Preescolar , Dieta , Humanos , Reproducción , Medición de Riesgo , Oligoelementos/análisis , Oligoelementos/toxicidad , Verduras
7.
Anal Methods ; 13(46): 5670-5678, 2021 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-34792519

RESUMEN

A simple, sensitive and matrix-effect free analytical method for simultaneous determination of Cd, Hg and Pb in drug samples (i.e., commercial dosage tablets) by inductively coupled plasma optical emission spectrometry (ICP OES) has been developed. According to the United States Pharmacopeia (USP) Chapter 232, those metals are considered elemental impurities from class 1 and they must be assessed in pharmaceutical production as well as in quality control evaluation. In order to increase the sensitivity of the analysis, dispersive liquid-liquid microextraction (DLLME) was performed and seven factors affecting analyte extraction were optimized by multivariate analysis. A microvolume of analyte enriched phase was directly introduced into the plasma using a multi-nebulizer, providing a high enrichment factor. When compared to conventional ICP OES analysis, DLLME improves the limit of quantitation (LOQ) values on average 40-fold for all analytes. Consequently, LOQ values were significantly lower than their permissible daily exposure limits for oral drugs. Accuracy was evaluated by addition and recovery experiments following USP recommendations in eight commercial drug samples. Recovery and RSD values were within the range of 90-108% and 1-9%, respectively.


Asunto(s)
Microextracción en Fase Líquida , Mercurio , Cadmio , Plomo , Análisis Espectral , Estados Unidos
8.
Anal Chim Acta ; 1185: 339052, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34711330

RESUMEN

A simple, fast, sensitive and green pretreatment method for determination of Cd, Co, Hg, Ni, Pb and V in oral and parenteral drug samples using inductively coupled plasma optical emission spectrometry (ICP OES) has been developed. According to United States Pharmacopoeia (USP), those metals must be reported in all pharmaceutical products for quality control evaluation (i.e., elemental impurities from classes 1 and 2A of USP Chapter 232). To improve the analytical capabilities of ICP OES, a dispersive liquid-liquid microextraction (DLLME) has performed using a safe, cheap and biodegradable deep eutectic solvent (DES) as extractant solvent (a mixture of 2:1 M ratio of DL-menthol and decanoic acid). Seven parameters affecting the microextraction efficiency have carefully optimized by multivariate analysis. Under optimized conditions, the DES-based DLLME-ICP OES procedure improved limit of quantitation (LOQ) values on range from 12 to 85-fold and afforded an enrichment factor on average 60-times higher than those obtained to direct ICP OES analysis. Consequently, LOQ values for Cd, Co, Hg, Ni, Pb and V have been on average 10-times lower than target limits recommended for drugs from parenteral route of administration. Trueness has evaluated by addition and recovery experiments following USP recommendations for three oral drug samples in liquid dosage form and three parenteral drugs. Recovery and RSD values have been within the range of 90-109% and 1-6%, respectively. All analytes were below the respectives LOQ values, hence, lower than the limits proposed by USP Chapter 232.


Asunto(s)
Microextracción en Fase Líquida , Preparaciones Farmacéuticas , Límite de Detección , Solventes , Análisis Espectral
9.
Talanta ; 220: 121395, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32928415

RESUMEN

In this study, a sensitive and matrix-effect free analytical method for Cd determination in engine oils and fuel samples by dispersive liquid-liquid microextraction with electrothermal atomic absorption spectrometry has been successfully developed. The extractant solvent used for the microextraction procedure was a magnetic ionic liquid (MIL) (i.e., bis(1-ethyl-3-methylimidazolium) tetrathiocyanatocobaltate (II) [Emim]2[Co(SCN)4]), which presents a paramagnetic property, and allows an easy phase separation using a magnet. In order to eliminate the well-known drawbacks of direct introduction of MIL in the graphite furnace, a back-extraction procedure was performed to transfer the analyte into an aqueous phase. The main experimental factors affecting the extraction of Cd (i.e., amount of sample and MIL, extraction and back-extraction time and concentration and amount of nitric acid) were optimized using a multivariate analysis consisting in two steps: a Plackett-Burman design followed by a circumscribed central composite design. Under optimum conditions (i.e., amount of sample: 6.2 g; amount of MIL: 119 mg; extraction time: 1 min; amount of nitric acid: 200 mg; nitric acid concentration: 1 mol L-1 and back-extraction time: 1 min), the proposed analytical method was validated and successfully used to analyze three real-world samples (i.e., used engine oil, gasoline and diesel). The three samples were spiked at two levels (i.e., 10 and 20 µg kg-1 of Cd for used engine oil and 1 and 3 µg kg-1 of Cd for gasoline and diesel). RSD and recovery values were within the range of 6-11% and 95-110%, respectively.

10.
RSC Adv ; 10(33): 19713-19719, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35515453

RESUMEN

A new, inexpensive and easy to use 3D printable device was developed for nephelometric and fluorimetric determination. Its applicability was tested for the quantification of quinine in tonic drinks and sulfate in natural water with good analytical accuracy. In this way, sulfate determination was carried out by nephelometry using a red LED, while quinine was determined using a blue LED by fluorimetry. A smartphone camera was used to take the pictures and afterwards transform them into the RGB color space using the software ImageJ by a personal computer. The linear range was 2.0-50.0 mg L-1 for sulfate with a LOD of 0.13 mg L-1, and the corresponding quantification limit (LOQ) was 0.43 mg L-1. The linear range for quinine was from 0.42 to 3.10 mg L-1. The LOD and LOQ were 0.11 mg L-1 and 0.38 mg L-1, respectively.

11.
Lab Chip ; 19(23): 3943-3953, 2019 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-31641717

RESUMEN

We demonstrate a rapid, 2-step, and ultrasensitive assay approach for quantification of target protein molecules from a single droplet test sample. The assay is comprised of antibody-conjugated gold nanoparticles (AuNPs) that are "activated" when they are mixed with the test sample and bind their targets. The resulting liquid is passed through a microfluidic channel with a photonic crystal (PC) biosensor that is functionalized with secondary antibodies to the target biomarker, so that only activated AuNPs are captured. Utilizing recently demonstrated hybrid optical coupling between the plasmon resonance of the AuNP and the resonance of the PC, each captured AuNP efficiently quenches the resonant reflection of the PC, thus enabling the captured AuNPs to be digitally counted with high signal-to-noise. To achieve a 2-step assay process that is performed on a single droplet test sample without washing steps or active pump elements, controlled single-pass flow rate is obtained with an absorbing paper pad waste reservoir embedded in a microfluidic cartridge. We use the activate capture and digital counting (AC + DC) approach to demonstrate HIV-1 capsid antigen p24 detection from a 40 µL spiked-in human serum sample at a one thousand-fold dynamic range (1-103 pg mL-1) with only a 35-minute process that is compatible with point-of-care (POC) analysis. The AC + DC approach allows for ultrasensitive and ultrafast biomolecule detection, with potential applications in infectious disease diagnostics and early stage disease monitoring.


Asunto(s)
Proteína p24 del Núcleo del VIH/análisis , Técnicas Analíticas Microfluídicas , Biomarcadores/análisis , Oro/química , Humanos , Límite de Detección , Nanopartículas del Metal/química , Técnicas Analíticas Microfluídicas/instrumentación , Tamaño de la Partícula , Sistemas de Atención de Punto , Propiedades de Superficie
12.
J Pharm Sci ; 108(8): 2593-2598, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30885661

RESUMEN

A rapid and portable analytical methodology has been developed for ibuprofen (IBU) quantification in commercial dosage tablets using a spectrometric smartphone-based system. The analytical methodology employs point-of-use approaches both for sample preparation and detection, demonstrating its potential utility for portable quality control of pharmaceutical products. In this work, IBU is dissolved in methanol and then treated with a Co(II) aqueous solution, forming a blue complex which is extractable by dispersive liquid-liquid microextraction. Then, the sample's absorption spectrum is directly measured by a spectrometric smartphone-based system using cartridge made of polyoxymethylene for solvent compatibility. The main experimental factors affecting the dispersive liquid-liquid microextraction of Co-IBU complex were optimized using a multivariate analysis. Under optimized conditions, a working range between 20 and 80 µg mL-1 was obtained with a correlation coefficient of 0.996 for 5 calibration points. The limit of detection and limit of quantification obtained were 4 and 12 µg mL-1, respectively. The performance of the proposed methodology was evaluated in commercial tablet dosage forms, and the results demonstrate the ability of the method to determine IBU in samples representative of those used in real-world quality control applications. Recovery values between 97% and 105% were obtained, which are comparable to those obtained via standard titrimetric methodology.


Asunto(s)
Analgésicos no Narcóticos/análisis , Antiinflamatorios no Esteroideos/análisis , Ibuprofeno/análisis , Microextracción en Fase Líquida/métodos , Teléfono Inteligente , Espectrofotometría/métodos , Comprimidos
13.
Food Chem ; 272: 141-147, 2019 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-30309524

RESUMEN

A rapid and portable analytical methodology has been developed for ascorbic acid (Vitamin C) quantification from aqueous samples using a spectrometric smartphone-based system for the first time. The method employs point-of-use approaches both for sample preparation and sample measurement, demonstrating the capability for mobile quality control of pharmaceutical and food products. Our approach utilizes an oxidation-reduction reaction between ascorbic acid and methylene blue, followed by a dispersive liquid-liquid microextraction (DLLME) to extract the aqueous-phase methylene blue into organic media. Then, a back-extraction procedure is employed to transfer the methylene blue to aqueous media, followed by analysis of the sample's absorption spectrum using the spectrometric smartphone-based system. The DLLME and back-extraction procedures are optimized by use of a two-step multivariate optimization strategy. Finally, vitamin C supplements and orange juice are used as real-world samples to assess the applicability of the smartphone-based method, which is successfully compared with the standard laboratory-based approach.


Asunto(s)
Ácido Ascórbico/análisis , Teléfono Inteligente , Análisis Espectral/métodos , Ácido Ascórbico/química , Ácido Ascórbico/aislamiento & purificación , Suplementos Dietéticos/análisis , Jugos de Frutas y Vegetales/análisis , Microextracción en Fase Líquida , Azul de Metileno/química , Sistemas de Atención de Punto , Agua/química
14.
Anal Bioanal Chem ; 409(23): 5481-5490, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28687885

RESUMEN

In this work, a new and simple analytical methodology based on in-chamber chemical vapor generation has been developed for the spectrochemical analysis of commercial fuel samples. A multiple nebulizer with three nebulization units has been employed for this purpose: One unit was used for sample introduction, while the other two were used for the necessary reagent introduction. In this way, the aerosols were mixed inside the spray chamber. Through this method, analyte transport and, therefore, sensitivity are improved in inductively coupled plasma-optical emission spectrometry. The factors (i.e., variables), influencing chemical vapor generation, have been optimized using a multivariate approach. Under optimum chemical vapor generation conditions ([NaBH4] = 1.39%, [HCl] = 2.97 M, total liquid flow = 936 µL min-1), the proposed sample introduction system allowed the determination of arsenic, selenium, and mercury up to 5 µg g-1 with a limit of detection of 25, 140, and 13 µg kg-1, respectively. Analyzing spiked commercial fuel samples, recovery values obtained were between 96 and 113%, and expanded uncertainty values ranged from 4 to 16%. The most striking practical conclusion of this investigation is that no carbon deposit appears on the plasma torch after extended periods of working. Graphical abstract A new and simple analytical methodology based on in-chamber chemical vapor generation has been developed for the spectrochemical analysis of commercial fuel samples in ICP OES.

15.
Ciudad Autónoma de Buenos Aires; Argentina. Ministerio de Salud de la Nación. Dirección de Investigación en Salud; jul. 2016. 1-26 p. tab, graf.
No convencional en Español | ARGMSAL, BINACIS | ID: biblio-1400858

RESUMEN

INTRODUCCION La medición ecográfica de segmentos fetales permite establecer la edad gestacional y evaluar el crecimiento fetal. La biometría fetal es una herramienta para detectar desviaciones del crecimiento, malformaciones y diagnosticar algunos síndromes genéticos. Existen numerosas tablas de la biometría fetal y las más usadas fueron elaboradas en otros países. OBJETIVO Seleccionar las tablas de la biometría fetal más adecuadas para evaluar los fetos de nuestra población y proponer su uso unificado en todo el país. Mejorar la detección de las alteraciones del crecimiento fetal. MÉTODOS Diseño; Estudio observacional, de corte transversal, prospectivo. Durante 9 meses 65 ecografistas obtuvieron medidas del Diámetro Biparietal, Circunferencia Cefálica, Circunferencia Abdominal y Longitud Femoral. Las medidas fueron cargadas a una base de datos de una página web. Los valores obtenidos se compararon con tablas de autores clásicos como Hadlock o Chitty y con las de autores sudamericanos como Fescina y Lagos, y las de Aguirre (CENAGEM) utilizando Z-score. Material; Mujeres embarazadas no seleccionadas de distintos lugares del país. RESULTADOS Se obtuvieron medidas de los distintos segmentos fetales de un total de 2384 embarazadas y para cada semana de edad gestacional. Se comparó el efecto sobre la distribución de frecuencia de las curvas publicadas por los otros autores usando Z-score. Se calculó el impacto clínico de la selección de tablas por medio de distintas tasas en relación con las medidas obtenidas y las esperadas por fuera de los percentilos 5 y 95. Se usó el índice de Youden para establecer la mejor relación entre sensibilidad y especificidad. No se pudo establecer estas relaciones con los autores que no publicaron sus ecuaciones de ajuste para los desvíos estándar. DISCUSIÓN Las tablas de Aguirre y cols para los 4 segmentos son las que mejor ajustan al haber obtenido el mejor Índice de Youden. Estas tablas son las que se sugieren para su uso unificado en la población Argentina


Asunto(s)
Biometría , Biometría/métodos , Insuficiencia de Crecimiento , Retardo del Crecimiento Fetal , Feto/diagnóstico por imagen
16.
Reprod Toxicol ; 43: 26-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24513926

RESUMEN

OBJECTIVE: Methotrexate (MTX) is a potent teratogen when used in high doses for cancer or termination of tubal pregnancy. In contrast, it has been perceived as safe when used once weekly at low dose for rheumatological conditions. METHODS: A prospective observational controlled study of women exposed to low dose MTX. The control group were women exposed to MTX only before conception. RESULTS: Among the 8 MTX-exposed pregnancies, there was a case of typical MTX embryopathy, the first to be described to date at this lower once weekly dose Schedule. CONCLUSIONS: This case has important implications for rheumatologists treating women of reproductive age, as the assumption of fetal safety of MTX, implied from small cohorts, is premature.


Asunto(s)
Anomalías Múltiples/inducido químicamente , Antirreumáticos/efectos adversos , Anomalías Craneofaciales/inducido químicamente , Enfermedades Fetales/inducido químicamente , Metotrexato/efectos adversos , Adolescente , Adulto , Antirreumáticos/uso terapéutico , Femenino , Humanos , Intercambio Materno-Fetal , Metotrexato/uso terapéutico , Embarazo , Enfermedades Reumáticas/tratamiento farmacológico , Adulto Joven
19.
Rev. venez. endocrinol. metab ; 9(3): 89-98, dic. 2011. ilus
Artículo en Español | LILACS-Express | LILACS | ID: lil-631293

RESUMEN

La enfermedad tiroidea autoinmune es una de las patologías más comunes dentro de la endocrinología. Este grupo de enfermedades que afectan la función tiroidea se consideran actualmente como parte de un espectro, donde por un lado se evidencia una hipofunción y donde predomina una respuesta inmune Th1 (Tiroiditis de Hashimoto) y en el lado opuesto, el de la hiperfunción, predomina una respuesta Th2 (Enfermedad de Graves). Si bien ambas enfermedades tienen ciertos locus de predisposición genética en común, las manifestaciones clínicas y el pronóstico de estas enfermedades son totalmente opuestas. Aunque se han planteado diversas teorías para explicar las diferencias en el patrón autoinmune de ambos extremos de este espectro, éstas no han logrado ilustrar la amplia variedad de fenotipos de esta patología. Evidencia actual sugiere que un grupo celular encargado de controlar la actividad de los elementos efectores de la respuesta inmune, limitando el daño hacia los tejidos del hospedador mediando la autotolerancia, y conocido como células T reguladoras, juegan un papel protagónico en el desarrollo de las enfermedades autoinmunes. El propósito de ésta revisión es exponer como la disregulación de la cara reguladora del sistema inmune, expresada tanto en la alteración de la función como en la expansión de las células T reguladoras, constituyen una piedra angular en las diversas formas de manifestación de la enfermedad tiroidea autoinmune.


Autoimmune thyroid disease is one of the most common diseases inside the field of endocrinology. This group of diseases affect the thyroid function in a manner that is now considered like a spectrum, where on one side there is evidence of hypofunction and a predominating Th1 response (Hashimoto´s thyroiditis), and on the opposite side, hyperfunction and a predominating Th2 response (Graves´ disease). Even though both diseases share loci for genetic predisposition, the outcome of each of them is totally opposite. Several theories have been proposed to explain the differences in the autoimmune patterns, but haven’t been able to explain the ample phenotypical manifestations of the disease. Current evidence suggests that a recently describe cellular group is in charge of controlling the effector elements of the immune response, limiting tissue damage and enhancing self-tolerance, these are the T regulator cells (Treg), which play a principal role in the development of autoimmune diseases. The purpose of this review is to expose the dysregulation of the regulatory side of the immune system expressed as the alteration of the functioning of Treg, which are now believed to be fundamental in the many phenotypes of autoimmune thyroid diseases.

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