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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 317: 124416, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38733915

RESUMO

The effects on the structure, valence state and morphological properties of FeCo-containing SnO2 nanostructured solids were investigated. The physicochemical features were tuned by distinct synthesis routes e.g., sol-gel, coprecipitation and nanocasting, to apply them as catalysts in the glycerol valorization to cyclic acetals. Based on Mössbauer and XPS spectroscopy results, all nanosized FeCoSn solids have Fe-based phases, which contain Co and Sn included in the structure, and well-dispersed Fe3+ and Fe2+ surface active sites. Raman, FTIR and EPR spectroscopies measurements of the spent solids demonstrated structural stability for the sol-gel based solid, which is indeed responsible for the highest catalytic performance, among the nanocasted and coprecipitated counterparts. Morphological and elemental analyses illustrated distinct morphologies and composition on solid surface, depending on the synthesis route. The Fe/Co and Fe/Sn surface ratios are closely related to the catalytic performance. The improved glycerol conversion and selectivities of the solid obtained by sol-gel method was ascribed to the leaching resistance and the Sn action as a structural promoter.

2.
J Food Sci Technol ; 60(7): 2012-2022, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37206429

RESUMO

Resistant starch (RS) promotes health benefits; however, when added to foods, it could change the rheological properties. The effect of adding different concentrations (2.5, 5, 7.5, and 10%) of retrograded corn starch with 27% (RNS) or 70% (RHS) amylose content on the properties of yogurt was evaluated through measurements of flow behavior and gel structure. Syneresis and resistant starch content were also assessed. Results were analyzed using multiple regression to describe the effect of starch concentration and storage time on the properties of yogurt added with RNS or RHS. Syneresis was reduced, RNS reinforced the structure increasing the water absorption capacity and the consistency index; meanwhile, RHS provided a yogurt containing up to 10 g of RS in 100 g of sample, allowing obtaining a functional dairy product. Creep-recovery test showed that adding RNS or RHS favored the matrix conformation, and the yogurt samples were able to recover. The final product behaved like a solid material with a firmer and more stable gel structure, resulting in a strengthened gel without weakening the yogurt structure, showing a characteristic like Greek-style or stirred yogurt depending on the type and concentration of retrograded starch. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05735-x.

3.
Otolaryngol Head Neck Surg ; 168(4): 643-657, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35349383

RESUMO

OBJECTIVE: To offer pragmatic, evidence-informed guidance on the use of systemic corticosteroids (SCS) for common otolaryngologic disorders. DATA SOURCES: PubMed, Cochrane Library, and American Academy of Otolaryngology-Head and Neck Surgery Foundation clinical practice guidelines. REVIEW METHODS: A comprehensive search of published literature through November 2021 was conducted on the efficacy of SCS, alone or in combination with other treatments, for managing disorders in otolaryngology and the subdisciplines. Clinical practice guidelines, systematic reviews, and randomized controlled trials, when available, were preferentially retrieved. Interventions and outcomes of SCS use were compiled to generate summary tables and narrative synthesis of findings. CONCLUSIONS: Evidence on the effectiveness of SCS varies widely across otolaryngology disorders. High-level evidence supports SCS use for Bell's palsy, sinonasal polyposis, and lower airway disease. Conversely, evidence is weak or absent for upper respiratory tract infection, eustachian tube dysfunction, benign paroxysmal positional vertigo, adenotonsillar hypertrophy, or nonallergic rhinitis. Evidence is indeterminate for acute laryngitis, acute pharyngitis, acute sinusitis, angioedema, chronic rhinosinusitis without polyps, Ménière's disease, postviral olfactory loss, postoperative nerve paresis/paralysis, facial pain, and sudden sensorineural hearing loss. IMPLICATIONS FOR PRACTICE: Clinicians should bring an evidence-informed lens to SCS prescribing to best counsel patients regarding the risks, anticipated benefits, and limited data on long-term effects. Alternate routes of corticosteroid administration-such as sprays, drops, inhalers, and intralesional injections-may be preferable for many disorders, particularly those that are self-limited or require a prolonged duration of therapy. Prudent use of SCS reduces the risk of medication-related adverse effects. Clinicians who are conversant with high-level evidence can achieve optimal outcomes and stewardship when prescribing SCS.


Assuntos
Paralisia de Bell , Otolaringologia , Otorrinolaringopatias , Sinusite , Humanos , Esteroides , Corticosteroides/uso terapêutico , Otorrinolaringopatias/tratamento farmacológico , Otorrinolaringopatias/cirurgia , Paralisia de Bell/tratamento farmacológico , Sinusite/tratamento farmacológico , Sinusite/cirurgia
4.
Bol Med Hosp Infant Mex ; 79(Supl 1): 1-31, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35943405

RESUMO

BACKGROUND: Acute otitis media (AOM) is one of the most prevalent acute conditions in the pediatric population worldwide. This work aimed to elaborate a Clinical Practice Guideline with clinical recommendations systematically developed to assist decision-making of specialists, patients, caregivers, and public policymakers involved in managing patients with AOM in children. METHODS: This document was developed by the College of Pediatric Otorhinolaryngology and Head, and Neck Surgery of Mexico (COPEME) in compliance with international standards. The SIGN quality of evidence classification was used. On behalf of the COPEME, the Guideline Development Group (GDG) was integrated, including otolaryngologists, infectologists, pediatricians, general practitioners, and methodologists with experience in systematic literature reviews and the development of clinical practice guidelines. RESULTS: A consensus was reached on 18 clinical questions, covering what was previously established by the GDG in the scope document of the guidelines. Scientific evidence answering each of these clinical questions was identified and critically evaluated. The GDG agreed on the final wording of the clinical recommendations using the modified Delphi panel technique. Specialists and patient representatives conducted an external validation. CONCLUSIONS: This Clinical Practice Guideline presents clinical recommendations for the prevention, diagnosis, and management of AOM to assist shared decision-making among physicians, patients, and caregivers and improve the quality of clinical care.


INTRODUCCIÓN: La otitis media aguda (OMA) es uno de los padecimientos agudos más prevalentes en la población pediátrica a escala global. El objetivo de este trabajo fue elaborar una guía de práctica clínica con recomendaciones para asistir la toma de decisiones de médicos especialistas, pacientes, cuidadores de pacientes y elaboradores de políticas públicas involucrados en el manejo de la OMA en niños. MÉTODOS: El documento ha sido desarrollado por parte del Colegio de Otorrinolaringología y Cirugía de Cabeza y Cuello Pediátricas de México (COPEME) en cumplimiento con los estándares internacionales. Se empleó la clasificación de calidad de la evidencia de SIGN. En representación del COPEME, se integró el Grupo de Desarrollo de la Guía (GDG), que incluyó otorrinolaringólogos, infectólogos, pediatras, médicos generales y metodólogos con experiencia en revisiones sistemáticas de la literatura y el desarrollo de guías de práctica clínica. RESULTADOS: Se consensuaron 18 preguntas clínicas que abarcaron lo establecido previamente por el GDG en el documento de alcances de la Guía. Se identificó la evidencia científica que responde a cada una de estas preguntas clínicas y se evaluó críticamente. El GDG acordó la redacción final de las recomendaciones clínicas mediante la técnica Delphi de panel. Se llevó a cabo una validación externa por colegas especialistas y representantes de pacientes. CONCLUSIONES: En esta Guía de Práctica Clínica se presentan recomendaciones clínicas para la prevención, el diagnóstico y el manejo de la OMA, con el fin de asistir la toma de decisiones compartidas entre médicos, pacientes y cuidadores con la intención de contribuir a mejorar la calidad de la atención clínica.


Assuntos
Otite Média , Doença Aguda , Criança , Humanos , México , Otite Média/diagnóstico
5.
Bioorg Med Chem Lett ; 63: 128649, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35245665

RESUMO

Zygomycetes are ubiquitous saprophytes in natural environments which transform organic matter. Some zygomycetes of gender Mucor have attracted interest in health sector. Due to its ability as opportunistic microorganisms infecting immuno-compromised people and to the few available pharmacological treatments, the mucormycosis is receiving worldwide attention. Concerning to the pharmacological treatments, some triazole-based compounds such as fluconazole are extensively used. Nevertheless, we focused in the quinolines since they are broadly used models for the design and development of new synthetic antifungal agents. In this study, the fungistatic activity on M. circinelloides of various 2-aryl-4-aryloxyquinoline-based compounds was discovered, and in some cases, it resulted better than reference compound fluconazole. These quinoline derivatives were synthesized via the Csp2-O bond formation using diaryliodonium(III) salts chemistry. A QSAR study was carried out to quantitatively correlate the chemical structure of the tested compounds with their biological activity. Also, a docking study to identify a plausible action target of our more active quinolines was carried out. The results highlighted an increased activity with the fluorine- and nitro-containing derivatives. In light of the few mucormycosis pharmacological treatments, herein we present some non-described molecules with excellent in vitro activities and potential use in the mucormycosis treatment.


Assuntos
Mucormicose , Quinolinas , Fluconazol , Humanos , Mucor , Mucormicose/tratamento farmacológico , Mucormicose/microbiologia , Relação Quantitativa Estrutura-Atividade , Quinolinas/farmacologia , Quinolinas/uso terapêutico
6.
Arch Cardiol Mex ; 92(Supl): 1-62, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35275904

RESUMO

ANTECEDENTES: Las enfermedades cardiovasculares son la principal causa mundial de mortalidad y México no es la excepción. Los datos epidemiológicos obtenidos en 1990 mostraron que los padecimientos cardiovasculares representaron el 19.8% de todas las causas de muerte en nuestro país; esta cifra se incrementó de manera significativa a un 25.5% para 2015. Diversas encuestas nacionales sugieren que más del 60% de la población adulta tiene al menos un factor de riesgo para padecer enfermedades cardiovasculares (obesidad o sobrepeso, hipertensión, tabaquismo, diabetes, dislipidemias). Por otro lado, datos de la Organización Panamericana de la Salud han relacionado el proceso de aterosclerosis como la primer causa de muerte prematura, reduciendo la expectativa de vida de manera sensible, lo que tiene una enorme repercusión social. OBJETIVO: Este documento constituye la guía de práctica clínica (GPC) elaborada por iniciativa de la Sociedad Mexicana de Cardiología en colaboración con la Sociedad Mexicana de Nutrición y Endocrinología, A.C., Asociación Nacional de Cardiólogos de México, A.C., Asociación Mexicana para la Prevención de la Aterosclerosis y sus Complicaciones, A.C., Comité Normativo Nacional de Medicina General, A.C., Colegio Nacional de Medicina Geriátrica, A.C., Colegio de Medicina Interna de México, A.C., Sociedad Mexicana de Angiología y Cirugía Vascular y Endovenosa, A.C., Instituto Mexicano de Investigaciones Nefrológicas, A.C. y la Academia Mexicana de Neurología, A.C.; con el apoyo metodológico de la Agencia Iberoamericana de Desarrollo y Evaluación de Tecnologías en Salud, con la finalidad de establecer recomendaciones basadas en la mejor evidencia disponible y consensuadas por un grupo interdisciplinario de expertos. El objetivo de este documento es el de brindar recomendaciones basadas en evidencia para ayudar a los tomadores de decisión en el diagnóstico y tratamiento de las dislipidemias en nuestro país. MATERIAL Y MÉTODOS: Este documento cumple con estándares internacionales de calidad, como los descritos por el Instituto de Medicina de EE.UU., el Instituto de Excelencia Clínica de Gran Bretaña, la Red Colegiada para el Desarrollo de Guías de Escocia y la Red Internacional de Guías de Práctica Clínica. Se integró un grupo multidisciplinario de expertos clínicos y metodólogos con experiencia en revisiones sistemáticas de la literatura y el desarrollo de guías de práctica clínica. Se consensuó un documento de alcances, se establecieron las preguntas clínicas relevantes, se identificó de manera exhaustiva la mejor evidencia disponible evaluada críticamente en revisiones sistemáticas de la literatura y se desarrollaron las recomendaciones clínicas. Se utilizó la metodología de Panel Delphi modificado para lograr un nivel de consenso adecuado en cada una de las recomendaciones contenidas en esta GPC. RESULTADOS: Se consensuaron 23 preguntas clínicas que dieron origen a sus respectivas recomendaciones clínicas. CONCLUSIONES: Esperamos que este documento contribuya a la mejor toma de decisiones clínicas y se convierta en un punto de referencia para los clínicos y pacientes en el manejo de las dislipidemias y esto contribuya a disminuir la morbilidad y mortalidad derivada de los eventos cardiovasculares ateroscleróticos en nuestro país. BACKGROUND: Cardiovascular diseases are the leading cause of mortality worldwide and Mexico is no exception. The epidemiological data obtained in 1990 showed that cardiovascular diseases represented 19.8% of all causes of death in our country. This figure increased significantly to 25.5% for 2015. Some national surveys suggest that more than 60% of the adult population has at least one risk factor for cardiovascular disease (obesity or overweight, hypertension, smoking, diabetes, dyslipidemias). On the other hand, data from the Pan American Health Organization have linked the process of atherosclerosis as the first cause of premature death, significantly reducing life expectancy, which has enormous social repercussions. OBJECTIVE: This document constitutes the Clinical Practice Guide (CPG) prepared at the initiative of the Mexican Society of Cardiology in collaboration with the Mexican Society of Nutrition and Endocrinology, AC, National Association of Cardiologists of Mexico, AC, Mexican Association for the Prevention of Atherosclerosis and its Complications, AC, National Normative Committee of General Medicine, AC, National College of Geriatric Medicine, AC, College of Internal Medicine of Mexico, AC, Mexican Society of Angiology and Vascular and Endovenous Surgery, AC, Mexican Institute of Research Nephrological, AC and the Mexican Academy of Neurology, A.C.; with the methodological support of the Ibero-American Agency for the Development and Evaluation of Health Technologies, in order to establish recommendations based on the best available evidence and agreed upon by an interdisciplinary group of experts. The objective of this document is to provide evidence-based recommendations to help decision makers in the diagnosis and treatment of dyslipidemias in our country. MATERIAL AND METHODS: This document complies with international quality standards, such as those described by the Institute of Medicine of the USA, the Institute of Clinical Excellence of Great Britain, the Scottish Intercollegiate Guideline Network and the Guidelines International Network. A multidisciplinary group of clinical experts and methodologists with experience in systematic reviews of the literature and the development of clinical practice guidelines was formed. A scope document was agreed upon, relevant clinical questions were established, the best available evidence critically evaluated in systematic literature reviews was exhaustively identified, and clinical recommendations were developed. The modified Delphi Panel methodology was used to achieve an adequate level of consensus in each of the recommendations contained in this CPG. RESULTS: 23 clinical questions were agreed upon which gave rise to their respective clinical recommendations. CONCLUSIONS: We consider that this document contributes to better clinical decision-making and becomes a point of reference for clinicians and patients in the management of dyslipidemias and this contributes to reducing the morbidity and mortality derived from atherosclerotic cardiovascular events in our country.

7.
Bol. méd. Hosp. Infant. Méx ; 79(supl.1): 1-31, jul. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1429933

RESUMO

Resumen Introducción: La otitis media aguda (OMA) es uno de los padecimientos agudos más prevalentes en la población pediátrica a escala global. El objetivo de este trabajo fue elaborar una guía de práctica clínica con recomendaciones para asistir la toma de decisiones de médicos especialistas, pacientes, cuidadores de pacientes y elaboradores de políticas públicas involucrados en el manejo de la OMA en niños. Métodos: El documento ha sido desarrollado por parte del Colegio de Otorrinolaringología y Cirugía de Cabeza y Cuello Pediátricas de México (COPEME) en cumplimiento con los estándares internacionales. Se empleó la clasificación de calidad de la evidencia de SIGN. En representación del COPEME, se integró el Grupo de Desarrollo de la Guía (GDG), que incluyó otorrinolaringólogos, infectólogos, pediatras, médicos generales y metodólogos con experiencia en revisiones sistemáticas de la literatura y el desarrollo de guías de práctica clínica. Resultados: Se consensuaron 18 preguntas clínicas que abarcaron lo establecido previamente por el GDG en el documento de alcances de la Guía. Se identificó la evidencia científica que responde a cada una de estas preguntas clínicas y se evaluó críticamente. El GDG acordó la redacción final de las recomendaciones clínicas mediante la técnica Delphi de panel. Se llevó a cabo una validación externa por colegas especialistas y representantes de pacientes. Conclusiones: En esta Guía de Práctica Clínica se presentan recomendaciones clínicas para la prevención, el diagnóstico y el manejo de la OMA, con el fin de asistir la toma de decisiones compartidas entre médicos, pacientes y cuidadores con la intención de contribuir a mejorar la calidad de la atención clínica.


Abstract Background: Acute otitis media (AOM) is one of the most prevalent acute conditions in the pediatric population worldwide. This work aimed to elaborate a Clinical Practice Guideline with clinical recommendations systematically developed to assist decision-making of specialists, patients, caregivers, and public policymakers involved in managing patients with AOM in children. Methods: This document was developed by the College of Pediatric Otorhinolaryngology and Head, and Neck Surgery of Mexico (COPEME) in compliance with international standards. The SIGN quality of evidence classification was used. On behalf of the COPEME, the Guideline Development Group (GDG) was integrated, including otolaryngologists, infectologists, pediatricians, general practitioners, and methodologists with experience in systematic literature reviews and the development of clinical practice guidelines. Results: A consensus was reached on 18 clinical questions, covering what was previously established by the GDG in the scope document of the guidelines. Scientific evidence answering each of these clinical questions was identified and critically evaluated. The GDG agreed on the final wording of the clinical recommendations using the modified Delphi panel technique. Specialists and patient representatives conducted an external validation. Conclusions: This Clinical Practice Guideline presents clinical recommendations for the prevention, diagnosis, and management of AOM to assist shared decision-making among physicians, patients, and caregivers and improve the quality of clinical care.

8.
Arch. cardiol. Méx ; 92(supl.1): 1-62, mar. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1383625

RESUMO

resumen está disponible en el texto completo


Abstract Background: Cardiovascular diseases are the leading cause of mortality worldwide and Mexico is no exception. The epidemiological data obtained in 1990 showed that cardiovascular diseases represented 19.8% of all causes of death in our country. This figure increased significantly to 25.5% for 2015. Some national surveys suggest that more than 60% of the adult population has at least one risk factor for cardiovascular disease (obesity or overweight, hypertension, smoking, diabetes, dyslipidemias). On the other hand, data from the Pan American Health Organization have linked the process of atherosclerosis as the first cause of premature death, significantly reducing life expectancy, which has enormous social repercussions. Objective: This document constitutes the Clinical Practice Guide (CPG) prepared at the initiative of the Mexican Society of Cardiology in collaboration with the Mexican Society of Nutrition and Endocrinology, AC, National Association of Cardiologists of Mexico, AC, Mexican Association for the Prevention of Atherosclerosis and its Complications, AC, National Normative Committee of General Medicine, AC, National College of Geriatric Medicine, AC, College of Internal Medicine of Mexico, AC, Mexican Society of Angiology and Vascular and Endovenous Surgery, AC, Mexican Institute of Research Nephrological, AC and the Mexican Academy of Neurology, A.C.; with the methodological support of the Ibero-American Agency for the Development and Evaluation of Health Technologies, in order to establish recommendations based on the best available evidence and agreed upon by an interdisciplinary group of experts. The objective of this document is to provide evidence-based recommendations to help decision makers in the diagnosis and treatment of dyslipidemias in our country. Material and methods: This document complies with international quality standards, such as those described by the Institute of Medicine of the USA, the Institute of Clinical Excellence of Great Britain, the Scottish Intercollegiate Guideline Network and the Guidelines International Network. A multidisciplinary group of clinical experts and methodologists with experience in systematic reviews of the literature and the development of clinical practice guidelines was formed. A scope document was agreed upon, relevant clinical questions were established, the best available evidence critically evaluated in systematic literature reviews was exhaustively identified, and clinical recommendations were developed. The modified Delphi Panel methodology was used to achieve an adequate level of consensus in each of the recommendations contained in this CPG. Results: 23 clinical questions were agreed upon which gave rise to their respective clinical recommendations. Conclusions: We consider that this document contributes to better clinical decision-making and becomes a point of reference for clinicians and patients in the management of dyslipidemias and this contributes to reducing the morbidity and mortality derived from atherosclerotic cardiovascular events in our country.

9.
Mater Sci Eng C Mater Biol Appl ; 125: 112097, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33965107

RESUMO

We report the synthesis of magnetite nanoparticles (MNP) and their functionalization with glycine (MNPGly), ß-alanine (MNPAla), L-phenylalanine (MNPPhAla), D-(-)-α-phenylglycine (MNPPhGly) amino acids. The functionalized nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), electron paramagnetic resonance (EPR), vibrating sample magnetometry (VSM), Mössbauer spectroscopy (MS), magnetic hyperthermia (MH), dynamic light scattering and zeta potential. The functionalized nanoparticles had isoelectric points (IEP) at pH ≃ 4.4, 5.8, 5.9 and 6.8 for samples MNPGly, MNPAla, MNPPhGly and MNPPhAla, respectively, while pure magnetite had an IEP at pH 5.6. In the MH experiments, the samples showed specific absorption rate (SAR) of 64, 71, 74, 81 and 66 W/g for MNP, MNPGly, MNPAla, MNPPhGly, and MNPPhAla, respectively. We used a flow cytometric technique to determine the cellular magnetic nanoparticles plus amino acids content. Magnetic fractionation and characterization of Resovist® magnetic nanoparticles were performed for applications in magnetic particle imaging (MPI). We have also studied the antiproliferative and antiparasitic effects of functionalized MNPs. Overall, the data showed that the functionalized nanoparticles have great potential for using as environmental, antitumor, antiparasitic agents and clinical applications.


Assuntos
Antimaláricos , Nanopartículas de Magnetita , Aminoácidos , Citometria de Fluxo , Humanos , Hipertermia , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Artigo em Inglês | MEDLINE | ID: mdl-33678136

RESUMO

The physicochemical treatment (PT) of food industry wastewater was investigated. In the first stage, calcium magnesium acetate (CaMgAc4) was synthesized using eggshell (biocalcium), magnesium oxide and acetic acid in a 1:1:1 stoichiometric ratio. In the synthesis process, the thermodynamic parameters (ΔH, ΔS and ΔG) indicated that the reaction was endothermic and spontaneous. The samples were characterized by infrared spectroscopy (IR), scanning electronic microscopy (SEM), X-ray diffraction (XRD) and electron X-ray dispersive spectroscopy (EDS). CaMgAc4 was used to precipitate the phosphate matter. IR analysis revealed that the main functional groups were representative of the acetate compounds and the presence of OH- groups and carbonates. In the physicochemical treatment, a response surface design was used to determine the variables that influence the process (pH, t, and concentration), and the response variable was phosphorus removal. The treatments were carried out in the wastewater industry with an initial concentration of 658 mg/L TP. The optimal conditions of the precipitation treatment were pH 12, time 12 min, and a CaMgAc4 concentration of 13.18 mg/L. These conditions allowed the total elimination (100%) of total phosphorus and phosphates, 81.43% BOD5 and 81.0% COD, 98.9% turbidity, 95.01% color, and 92% nitrogen matter.


Assuntos
Cálcio/química , Casca de Ovo/química , Indústria Alimentícia , Fosfatos/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Acetatos/química , Animais , Precipitação Química , Concentração de Íons de Hidrogênio , Óxido de Magnésio/química , Fosfatos/análise , Fosfatos/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
11.
Int J Biol Macromol ; 164: 4245-4251, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32890567

RESUMO

The aim of this work consists in the use of cashew gum (Anacardium occidentale), a naturally occurring tropical specie from the Brazilian northeastern coast, for the synthesis of CoFe2O4 (CF) and NiFe2O4 (NF) nanoparticles. The structural, morphological and vibrational properties of nanoparticles were characterized by analytical and spectroscopic techniques such as X-ray diffraction (XRD), FTIR, Raman spectroscopy, TEM, SAED and TG. Magnetic properties were investigated through Mössbauer spectroscopy and DC magnetometry. The XRD results showed single phase nanoparticles with space group Fd-3m and crystallite size of 7.4 and 6.0 for CF and NF, respectively. TEM images showed agglomerated particles with mode sizes of 5.0 and 6.5 nm for CF and NF. SAED confirmed the crystalline spinel structure. The TGA and FTIR showed the presence of a carbonaceous material in the samples. FTIR and Raman spectroscopy demonstrated vibrational modes characteristic of metal­oxygen bonds in the tetrahedral and octahedral sites. Magnetization measurements showed that both samples are superparamagnetic at 300 K. The Mössbauer spectra at 90 K showed the presence of single-phase CF and NF.


Assuntos
Anacardium/química , Cobalto/química , Géis/química , Nanoestruturas/química , Níquel/química , Gomas Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Termogravimetria , Difração de Raios X
12.
AAPS PharmSciTech ; 18(6): 2026-2036, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27966176

RESUMO

The treatment of peptic ulcers induced by H. pylori remains challenging due to the deep mucous layer location of bacteria preventing antimicrobial drug access. The present work aimed to design and evaluate in vitro dual responsive (both pH and magnetic field-sensitive) polymeric magnetic particles loaded with amoxicillin as a smart drug carrier for deep mucous layer penetration and in situ drug release. Magnetite particles were produced by the co-precipitation method and subsequently coated with the Eudragit®S100 and amoxicillin by using the spray-drying technique. The physicochemical characterization of the obtained particles was carried out by optical and scanning electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption isotherms, and vibrating sample magnetometry. Additionally, drug release tests and antibacterial activity tests were evaluated in vitro. Microparticles presented 17.2 ± 0.4 µm in size and their final composition was 4.3 ± 1.5% of amoxicillin, 87.0 ± 2.3% of Eudragit, and 9.0 ± 0.3% of magnetite. They were both pH and magnetic field responsive while presenting antimicrobial activity. On one side, magnetic field responsiveness of particles is expected to prompt them to reach bacterium niche in deep mucous layer by means of magnetic forces. On the other side, pH responsiveness is expected to enable drug release in the neutral pH of the deep mucous layer, preventing undesired delivery in the acidic gastric lumen. Smart microparticles were designed presenting both pH and magnetic field responsiveness as well as antimicrobial activity. These may be promising assets for peptic ulcer treatment.


Assuntos
Amoxicilina/síntese química , Anti-Infecciosos/síntese química , Portadores de Fármacos/síntese química , Fármacos Gastrointestinais/síntese química , Fenômenos Magnéticos , Amoxicilina/farmacologia , Antibacterianos/síntese química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Portadores de Fármacos/farmacologia , Composição de Medicamentos/métodos , Fármacos Gastrointestinais/farmacologia , Helicobacter pylori/efeitos dos fármacos , Microscopia Eletrônica de Varredura/métodos , Tamanho da Partícula , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X/métodos
13.
Eur J Ophthalmol ; 26(2): 128-34, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26350997

RESUMO

PURPOSE: To use multimodal imaging to evaluate the prevalence of reticular pseudodrusen (RPD) in eyes with newly presenting neovascular age-related macular degeneration (nAMD) in a UK population and explore associations with RPD and angiographic subtypes of nAMD. METHODS: A retrospective review of all spectral-domain optical coherence tomography, color fundus photographs, red-free and blue channel images, and fundus fluorescein angiograms of 202 consecutive patients who presented to a rapid access macular clinic over a 4-year period was performed. All images were graded by at least 2 ophthalmologists for the presence of RPD and choroidal neovascular membrane (CNV) subtypes. RESULTS: A total of 231 consecutive eyes were studied, of which 131 (56.7%) were in women. Of these, 51 eyes with CNV (22.1%) had identifiable RPD, with one or more imaging methods in that eye. A total of 30.3% of patients with newly presenting CNV in either or both eyes had identifiable RPD. The RPD were bilateral in 85.4% of patients and were identified more commonly in women than men (72.5% vs 27.5%), a difference that reached statistical significance (p = 0.011). No association between RPD and any particular CNV subtype was demonstrated, including for retinal angiomatous proliferations (RAP). CONCLUSIONS: Reticular pseudodrusen have a high prevalence in eyes presenting with nAMD (22.1%), although at rates much lower than that of conventional drusen. They are largely a bilateral finding, occurring more frequently in women. Unlike other previous reports, we found no difference in their occurrence between the different subtypes of CNV including RAPs.


Assuntos
Drusas Retinianas/epidemiologia , Degeneração Macular Exsudativa/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Neovascularização de Coroide/diagnóstico , Neovascularização de Coroide/epidemiologia , Feminino , Angiofluoresceinografia , Humanos , Masculino , Imagem Multimodal , Fotografação , Prevalência , Drusas Retinianas/diagnóstico , Estudos Retrospectivos , Tomografia de Coerência Óptica , Reino Unido/epidemiologia , Degeneração Macular Exsudativa/diagnóstico
14.
J Colloid Interface Sci ; 342(2): 269-77, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19917508

RESUMO

Magnetic mesoporous particles were synthesized and their magnetic and structural properties are reported. The synthesis procedure consists of four steps: (i) preparation of magnetite colloidal nanoparticles; (ii) growth of a silica layer; (iii) development of the mesoporous structure and (iv) template removal. Two different methods for the template removal were studied and their effectiveness was discussed. Magnetization and Mössbauer spectroscopy measurements showed superparamagnetic behavior for the particles at room temperature. X-ray diffraction and nitrogen adsorption measurements showed a mesoporous MCM-41 structure with 2.48nm pore diameter and 1023m(2)/g total area.

15.
J Neurosci Res ; 87(11): 2509-19, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19326446

RESUMO

Na(x) is a sodium channel, thought to be a descendant of the voltage-gated sodium channel family. Nevertheless, Na(x) is not activated by voltage but rather by augmentation of extracellular sodium over 150 mM. In the brain, it is localized to the circumventricular organs, important regions for salt and water homeostasis in mammals, where it operates as a sodium-level sensor of body fluid. Na(x) channel is expressed in lung, uterus, and heart, and it is also found in trigeminal and dorsal root ganglia and in nonmyelinating Schwann cells, where its physiological role remains unclarified. Here we identified the promoter and transcription start sites of Na(x) sodium channel in dorsal root ganglia neurons from mouse. We report a characterization of the basal TATA-less promoter and the sequence requirements for promoter activity in Neuro 2A neuroblastoma cells and in dorsal root ganglia neurons, where basal promoter activity seems to require NGFI-C and Ebox DNA elements. Finally, we provide evidence that a repression mechanism that inhibits Na(x) expression may be present in certain tissues. These findings provide the basis with which to understand tissue-specific regulation of Na(x) sodium channel gene (Scn7a) expression.


Assuntos
Gânglios Espinais/metabolismo , Neurônios/metabolismo , Regiões Promotoras Genéticas , Canais de Sódio/genética , Canais de Sódio/metabolismo , Animais , Linhagem Celular Tumoral , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Gânglios Espinais/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Neurônios/efeitos dos fármacos , RNA Mensageiro/metabolismo , Transcrição Gênica , Canais de Sódio Disparados por Voltagem
16.
Mol Pharm ; 5(2): 316-27, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18217714

RESUMO

It is essential to determine the biodistribution, clearance, and biocompatibility of magnetic nanoparticles (MNPs) for in vivo biomedical applications to ensure their safe clinical use. We have studied these aspects with our novel iron oxide MNP formulation, which can be used as a magnetic resonance imaging (MRI) agent and a drug carrier system. Changes in serum and tissue iron levels were analyzed over 3 weeks after intravenous administration of MNPs to rats. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AKP) levels, and total iron-binding capacity (TIBC) were also measured with time to assess the effect of MNPs on liver function. Selected tissues were also analyzed for oxidative stress and studied histologically to determine biocompatibility of MNPs. Serum iron levels gradually increased for up to 1 week but levels slowly declined thereafter. Biodistribution of iron in various body tissues changed with time but greater fraction of the injected iron localized in the liver and spleen than in the brain, heart, kidney, and lung. Magnetization measurements of the liver and spleen samples showed a steady decrease over 3 weeks, suggesting particle degradation. Serum showed a transient increase in ALT, AST, AKP levels, and TIBC over a period of 6-24 h following MNP injection. The increase in oxidative stress was tissue dependent, reaching a peak at approximately 3 days and then slowly declining thereafter. Histological analyses of liver, spleen, and kidney samples collected at 1 and 7 days showed no apparent abnormal changes. In conclusion, our MNPs did not cause long-term changes in the liver enzyme levels or induce oxidative stress and thus can be safely used for drug delivery and imaging applications.


Assuntos
Compostos Férricos/farmacocinética , Magnetismo , Nanopartículas , Alanina Transaminase/sangue , Animais , Portadores de Fármacos , Compostos Férricos/toxicidade , Ferro/sangue , Fígado/efeitos dos fármacos , Fígado/fisiologia , Imageamento por Ressonância Magnética , Masculino , Teste de Materiais , Taxa de Depuração Metabólica , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
17.
Mol Pharm ; 2(3): 194-205, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15934780

RESUMO

We have developed a novel water-dispersible oleic acid (OA)-Pluronic-coated iron oxide magnetic nanoparticle formulation that can be loaded easily with high doses of water-insoluble anticancer agents. Drug partitions into the OA shell surrounding iron oxide nanoparticles, and the Pluronic that anchors at the OA-water interface confers aqueous dispersity to the formulation. Neither the formulation components nor the drug loading affected the magnetic properties of the core iron oxide nanoparticles. Sustained release of the incorporated drug is observed over 2 weeks under in vitro conditions. The nanoparticles further demonstrated sustained intracellular drug retention relative to drug in solution and a dose-dependent antiproliferative effect in breast and prostate cancer cell lines. This nanoparticle formulation can be used as a universal drug carrier system for systemic administration of water-insoluble drugs while simultaneously allowing magnetic targeting and/or imaging.


Assuntos
Antineoplásicos Fitogênicos , Sistemas de Liberação de Medicamentos , Compostos Férricos/química , Compostos Férricos/farmacocinética , Nanotecnologia , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/farmacocinética , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Feminino , Compostos Férricos/administração & dosagem , Humanos , Magnetismo , Masculino , Microscopia Eletrônica de Transmissão , Microesferas , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Células Tumorais Cultivadas
18.
Cir. & cir ; 64(4): 118-21, jul.-ago. 1996. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-184092

RESUMO

El síndrome de transfusión feto-feto es una complicación de los embarazos gemelares monocigóticos-monocoriónicos, que se presenta en el segundo trimestre, con una mortalidad perinatal mayor del 60 por ciento. La presencia de anastomosis vasculares dentro de la placenta es la responsable del síndrome. El diagnóstico requiere la comprobación ultrasonográfica de monocorionicidad, de la secuencia oligohidramnios-polihidramnios, de discordancia en el crecimiento fetal y valores divergentes de hemoglobina y hematócrito. La indometacina, la amniocentesis y la cirugía endoscópica fetal pueden disminuir la elevada tasa de mortalidad perinatal. Si bien el pronóstico perinatal parece estar relacionado con la morbimortalidad a corto plazo, es recomendable realizar segumiento a largo plazo


Assuntos
Gravidez , Humanos , Transfusão Feto-Fetal/diagnóstico , Transfusão Feto-Fetal/embriologia , Transfusão Feto-Fetal/fisiopatologia , Placenta/irrigação sanguínea , Poli-Hidrâmnios , Gêmeos , Ultrassonografia Pré-Natal
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