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1.
Phys Chem Chem Phys ; 26(29): 19876-19886, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38989901

RESUMEN

With the increasing amount of renewable energy produced, many governments and industries are pushing for the installation of battery energy storage system (BESS) solutions. Thermal batteries are systems that store heat made from various energy sources, and can be used to produce electricity upon demand. These systems are easily scalable and can be installed in cities, homes and remote locations. Thermochemical energy storage (TCES) uses the enthalpy of a chemical reaction to store and release heat through endothermic and exothermic processes, respectively. CaCO3 has been identified as an ideal TCES material as it is cheap and abundant, but maximising long-term cyclability is key to ensure battery longevity. This article investigates the addition of CaSiO3, CaTiO3 and CaZrO3 to CaCO3 in a 1 : 1 ratio to ascertain the reaction properties and cyclic capacity over time. Cycling longevity and thermodynamic properties were determined using simultaneous differential scanning calorimetry and thermogravimetric analysis (DSC-TGA) along with the Sieverts technique, and their reaction pathway studied by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The low cost of the CaCO3-CaSiO3 material of $1.8 USD per kW hth suggests that if a suitable particle refinement agent were to be employed to ensure cycling longevity this material would be an excellent TCES material. Despite the CO2 cycling capacity of the CaCO3-CaZrO3 system only reducing by 16 wt% over 100 cycles, the cost of ZrO2 brings the materials cost to $30.9 USD per kW hth, making this material currently unsuitable for application. The CaCO3-CaTiO3 system showed only a 17% drop in total CO2 uptake over 100 cycles, although the cost was $11.1 USD per kW hth.

2.
Inorg Chem ; 61(51): 20757-20773, 2022 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-36519680

RESUMEN

A hydrophobic Schiff base catecholate vanadium complex was recently discovered to have anticancer properties superior to cisplatin and suited for intratumoral administration. This [VO(HSHED)(DTB)] complex, where HSHED is N-(salicylideneaminato)-N'-(2-hydroxyethyl)-1,2-ethanediamine and the non-innocent catecholato ligand is di-t-butylcatecholato (DTB), has higher stability compared to simpler catecholato complexes. Three new chloro-substituted Schiff base complexes of vanadium(V) with substituted catecholates as co-ligands were synthesized for comparison with their non-chlorinated Schiff base vanadium complexes, and their properties were characterized. Up to four geometric isomers for each complex were identified in organic solvents using 51V and 1H NMR spectroscopies. Spectroscopy was used to characterize the structure of the major isomer in solution and to demonstrate that the observed isomers are exchanged in solution. All three chloro-substituted Schiff base vanadium(V) complexes with substituted catecholates were also characterized by UV-vis spectroscopy, mass spectrometry, and electrochemistry. Upon testing in human glioblastoma multiforme (T98g) cells as an in vitro model of brain gliomas, the most sterically hindered, hydrophobic, and stable compound [t1/2 (298 K) = 15 min in cell medium] was better than the two other complexes (IC50 = 4.1 ± 0.5 µM DTB, 34 ± 7 µM 3-MeCat, and 19 ± 2 µM Cat). Furthermore, upon aging, the complexes formed less toxic decomposition products (IC50 = 9 ± 1 µM DTB, 18 ± 3 µM 3-MeCat, and 8.1 ± 0.6 µM Cat). The vanadium complexes with the chloro-substituted Schiff base were more hydrophobic, more hydrolytically stable, more easily reduced compared to their corresponding parent counterparts, and the most sterically hindered complex of this series is only the second non-innocent vanadium Schiff base complex with a potent in vitro anticancer activity that is an order of magnitude more potent than cisplatin under the same conditions.


Asunto(s)
Complejos de Coordinación , Vanadio , Humanos , Vanadio/farmacología , Vanadio/química , Cisplatino , Bases de Schiff/farmacología , Bases de Schiff/química , Agua , Espectroscopía de Resonancia Magnética , Complejos de Coordinación/farmacología , Ligandos
3.
Adv Exp Med Biol ; 1357: 225-257, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35583647

RESUMEN

An exponential increase in products containing titanium dioxide nanomaterials (TiO2), in agriculture, food and feed industry, lead to increased oral exposure to these nanomaterials (NMs). Thus, the gastrointestinal tract (GIT) emerges as a possible route of exposure that may drive systemic exposure, if the intestinal barrier is surpassed. NMs have been suggested to produce adverse outcomes, such as genotoxic effects, that are associated with increased risk of cancer, leading to a concern for public health. However, to date, the differences in the physicochemical characteristics of the NMs studied and other variables in the test systems have generated contradictory results in the literature. Processes like human digestion may change the NMs characteristics, inducing unexpected toxic effects in the intestine. Using TiO2 as case-study, this chapter provides a review of the works addressing the interactions of NMs with biological systems in the context of intestinal tract and digestion processes, at cellular and molecular level. The knowledge gaps identified suggest that the incorporation of a simulated digestion process for in vitro studies has the potential to improve the model for elucidating key events elicited by these NMs, advancing the nanosafety studies towards the development of an adverse outcome pathway for intestinal effects.


Asunto(s)
Nanoestructuras , Titanio , Tracto Gastrointestinal/metabolismo , Humanos , Intestinos , Nanoestructuras/química , Nanoestructuras/toxicidad , Titanio/química , Titanio/toxicidad
4.
Int J Food Sci Nutr ; 71(8): 954-964, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32393141

RESUMEN

Soy consumption and its components, including its protein, are related to the beneficial effects of the lipid profile, decreased insulin resistance and glycaemia. However, the safety of the consumption of products containing phytoestrogens in critical stages of development has been questioned, since they may be associated with endocrine-metabolic dysfunctions in adult life. The purpose is to evaluate the effects of maternal dietary soy protein isolate (SPI) during lactation on the breast milk composition, body composition, lipid and glycaemic profiles, and thyroid hormones of dams and offspring at weaning (21 days) and in adulthood (150 days). Lactating rats were divided into casein control (C) and SPI diet groups. At 150 days, the SPI offspring presented lower body protein mass and total mineral content, higher serum FT4, insulin, TC and TG. Maternal consumption of SPI during lactation programmes the progeny to higher metabolic risk profile.


Asunto(s)
Dieta , Lactancia/efectos de los fármacos , Fenómenos Fisiologicos Nutricionales Maternos/efectos de los fármacos , Proteínas de Soja/administración & dosificación , Animales , Glucemia , Composición Corporal/efectos de los fármacos , Femenino , Insulina/sangre , Lípidos/sangre , Masculino , Leche Humana , Ratas , Ratas Wistar , Destete
5.
Angew Chem Int Ed Engl ; 59(37): 15834-15838, 2020 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-32598089

RESUMEN

The chemistry and short lifetimes of metal-based anti-cancer drugs can be turned into an advantage for direct injections into tumors, which then allow the use of highly cytotoxic drugs. The release of their less toxic decomposition products into the blood will lead to decreased toxicity and can even have beneficial effects. We present a ternary VV complex, 1 ([VOL1 L2 ], where L1 is N-(salicylideneaminato)-N'-(2-hydroxyethyl)ethane-1,2-diamine and L2 is 3,5-di-tert-butylcatechol), which enters cells intact to induce high cytotoxicity in a range of human cancer cells, including T98g (glioma multiforme), while its decomposition products in cell culture medium were ≈8-fold less toxic. 1 was 12-fold more toxic than cisplatin in T98g cells and 6-fold more toxic in T98g cells than in a non-cancer human cell line, HFF-1. Its high toxicity in T98g cells was retained in the presence of physiological concentrations of the two main metal-binding serum proteins, albumin and transferrin. These properties favor further development of 1 for brain cancer treatment by intratumoral injections.


Asunto(s)
Antineoplásicos/química , Neoplasias Encefálicas/tratamiento farmacológico , Complejos de Coordinación/química , Compuestos de Vanadio/química , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Complejos de Coordinación/uso terapéutico , Medios de Cultivo , Descubrimiento de Drogas , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Espectroscopía de Protones por Resonancia Magnética , Compuestos de Vanadio/uso terapéutico
7.
An Acad Bras Cienc ; 88(3): 1212-20, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27580360

RESUMEN

The adsorption of Violet Remazol 5R (VR 5) on wood sawdust modified with succinic anhydride (SSA) as a function of contact time, pH, and initial dye concentrations was investigated using a batch technique under ambient conditions. The SSA obtained was confirmed by IR spectroscopy, thermogravimetry and 13C NMR, and degrees of substitution (DS) were calculated. A study on the effect of the pH on the adsorption of VR 5 showed that the optimum pH was 2.0. The interactions were assayed with respect to the pseudo-first-order and pseudo-second-order kinetic models, and were found to follow closely the pseudo-second-order. The isotherm was adjusted to the Langmuir, the Freundlich and the Temkin sorption models. SSA is a promising material for the removal of dye textile from aqueous solutions, and under conditions studied the removal percentage achieved was 51.7%.

8.
Chem Commun (Camb) ; 58(82): 11559-11562, 2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36165050

RESUMEN

A new solid-state method was used to introduce a furan-thiourea polymer into the pores of a MOF, Cr-BDC. Next, the activity of the new MOF-polymer composite containing Pd was assessed in the catalytic hydrodeoxygenation of vanillin, a biomass derived chemical.


Asunto(s)
Furanos , Polímeros , Benzaldehídos , Catálisis , Tiourea
9.
Stem Cell Res ; 61: 102757, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35339881

RESUMEN

Angelman Syndrome is a rare neurodevelopmental disorder caused by several (epi)genetic alterations. The patients present strong neurological impairment due to the absence of a functional maternal UBE3A gene in neurons. Here, we generated and characterized a new induced pluripotent stem cell (iPSC) line from a female child with Angelman syndrome harbouring a class II deletion. iPSCs were reprogrammed from fibroblasts using Sendai viruses. The new iPSCs express pluripotency markers, are capable of trilineage in vitro differentiation and have the expected imprinting status of Angelman syndrome. These iPSCs are a valuable tool to elucidate the pathophysiological mechanisms associated with this disease.


Asunto(s)
Síndrome de Angelman , Células Madre Pluripotentes Inducidas , Síndrome de Angelman/genética , Diferenciación Celular , Niño , Deleción Cromosómica , Cromosomas , Cromosomas Humanos Par 15 , Femenino , Humanos , Células Madre Pluripotentes Inducidas/citología , Neuronas
10.
Food Chem Toxicol ; 161: 112841, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35093430

RESUMEN

The widespread use of titanium dioxide nanomaterials (TiO2 NMs) in food and consumer products such as toothpaste or food contact materials, suggests the relevance of human oral exposure to these nanomaterials (NMs) and raises the possibility of adverse effects in the gastrointestinal tract (GIT). We previously showed that the in vitro digestion of TiO2 NMs may increase their toxicity in intestinal cells. In this work, we analyzed the genotoxicity and the intracellular reactive oxygen species induction by physiologically relevant concentrations of three different TiO2 NMs (NM-102, NM-103 and NM-105) in Caco-2 and HT29-MTX-E12 intestinal cells, while considering the potential influence of the digestion process in the NMs' physiochemical characteristics. The results evidenced a DNA-damaging effect dependent on the NM, more relevant for the rutile/anatase NM-105, possibly due to its lower hydrodynamic size in the cells medium. In addition, the results of the micronucleus assay suggest effects on chromosomal integrity, an indicator of cancer risk, in the HT29-MTX-E12 cells, for all the tested TiO2 NMs, especially after the in vitro digestion. This work supports the evidence for concerns on the use of TiO2 NMs as a food additive, recently reported by EFSA, and for their use in applications in consumer products that may drive human exposure through ingestion.


Asunto(s)
Intestinos/citología , Nanoestructuras/efectos adversos , Titanio/efectos adversos , Células CACO-2 , Neoplasias del Colon , Daño del ADN/efectos de los fármacos , Células HT29 , Humanos , Peróxido de Hidrógeno , Pruebas de Micronúcleos , Nanoestructuras/química , Especies Reactivas de Oxígeno , Titanio/química
11.
Dent Clin North Am ; 65(4): 775-785, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34503666

RESUMEN

This article is intended to familiarize clinicians with several pulp therapy modalities and new materials that are currently available for immature young pulp in the adolescent population. Objectives and considerations for immature young permanent teeth as well as the healing potential of the young pulp tissue after treatment of the inflammatory process are discussed. The article emphasizes that the future holds great possibilities for the regeneration of dental pulp in adolescent patients.


Asunto(s)
Caries Dental , Pulpotomía , Adolescente , Niño , Atención Odontológica , Recubrimiento de la Pulpa Dental , Dentición Permanente , Humanos , Resultado del Tratamiento
12.
Biochem Med (Zagreb) ; 31(2): 020711, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-34140834

RESUMEN

INTRODUCTION: Epithelial cells (ECs) are structures regularly observed during urine microscopy analysis. The correct identification of EC subtypes can be useful since renal tubular epithelial cells (RTECs) are clinically relevant. We investigate the urinary ECs report and the judgement of its clinical importance by Brazilian laboratories. MATERIALS AND METHODS: A survey with four questions was made available to participants of the Urinalysis External Quality Assessment Program (EQAP) from Controllab. Laboratories composed 3 groups: (1) differentiating ECs subtypes: "squamous", "transitional" and "RTECs"; (2) differentiating ECs subtypes: "squamous" or "non-squamous" cells; (3) without ECs subtype identification. Participants did not necessarily answer to all questions and the answers were evaluated both within the same laboratory's category and within different categories of laboratories. RESULTS: A total of 1336 (94%) laboratories answered the survey; Group 1, 119/140 (85%) reported that ECs differentiation is important to the physician and 62% want to be evaluated by EQAP, while in Group 3, 455/1110 (41%) reported it is useful to them, however only 25% want be evaluated by EQAP. Group 2 laboratories 37/51 (73%) reported that the information is important, but only 13/52 (25%) are interested in an EQAP with differentiation of the 3 ECs subtypes. CONCLUSION: Most of the laboratories do not differentiate ECs in the three subtypes, despite the clinical importance of RTECs. Education of laboratory staff about the clinical significance of urinary particles should be considered a key priority.


Asunto(s)
Células Epiteliales , Laboratorios de Hospital , Urinálisis , Brasil , Células Epiteliales/metabolismo , Células Epiteliales/patología , Femenino , Humanos , Masculino
13.
Nanomaterials (Basel) ; 10(8)2020 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-32748892

RESUMEN

Several metallic nanomaterials (NMs), such as titanium dioxide nanomaterials (TiO2), present beneficial properties with a broad range of innovative applications. The human population is exposed to TiO2, particularly by ingestion, due to its increasing use as a food additive and inclusion in dietary supplements and food packaging materials. Whether this oral exposure may lead to adverse local or systemic outcomes has been the subject of research, but studies have generated contradictory results, reflecting differences in the physicochemical properties of the TiO2 studied, effects of the surrounding matrix, and modifications during digestion. This work aimed to investigate the toxic effects of three different TiO2 NMs (NM-103, NM-103 and NM-105) on the gastrointestinal tract cells, Caco-2 and HT29-MTX-E12, after the use of the standardized static INFOGEST 2.0 in vitro digestion method to mimic human digestion of TiO2, contributing to hazard assessment. The results show that, for one of the digested TiO2 NMs studied (NM-105), a more pronounced toxicity occurs after exposure of HT29-MTX-E12 intestinal cells, as compared to undigested NM, concomitantly with subtle changes in characteristics of the NM. Thus, the inclusion of the digestion simulation in the safety evaluation of ingested NMs through in vitro bioassays can better integrate the modifications that NMs suffer in the organism. It is expected that such an approach will reduce uncertainties in the hazard assessment of ingested NMs for human health.

14.
Endocrine ; 60(2): 272-281, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29520624

RESUMEN

PURPOSE: To evaluate the effects of maternal dietary soybean during lactation on the milk composition, body composition, lipid profile and glucose homeostasis of dams and offspring at weaning (21 days) and adulthood (150 days). METHODS: Lactating rats were divided into: casein control (C): casein diet; soy (S): soybean diet; soy oil control (SOC): casein diet, but with fat content similar to the S group. RESULTS: At 21 days, S mothers showed lower estradiol, total cholesterol (TC), low-density lipoprotein cholesterol (LDL) and triglycerides (TG) in serum; and lower TC and TG in milk. The S offspring had lower body weight, body fat mass, TC, LDL, hyperleptinemia and hypertriglyceridemia. At 150 days, S offspring presented higher total mineral content and lower TC (v. SOC) and LDL (v. C and SOC), and hyperinsulinemia with lower glycemia v. SOC group, which had lower insulinemia with higher glycemia, TC and LDL. CONCLUSIONS: Maternal intake of soybeans in lactation changes the lipid content of breast milk and programmed offspring for phenotype of the lower metabolic risk, with lower serum TC and LDL, and seems to protect the progeny of alterations in glucose metabolism despite the higher lipid content. The difference in fat content of breast milk and the higher isoflavones content of soy diet are possible imprinting factors that could program the offspring.


Asunto(s)
Composición Corporal , Lactancia , Exposición Materna , Leche/química , Alimentos de Soja , Animales , Glucemia , LDL-Colesterol/sangre , Dieta/veterinaria , Femenino , Insulina/sangre , Leptina/sangre , Masculino , Embarazo , Distribución Aleatoria , Ratas Wistar , Glycine max , Destete
15.
J Inorg Biochem ; 165: 108-118, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27503192

RESUMEN

Herein, the design and syntheses of two new mononuclear oxindolimine-copper(II) (1 and 2) and corresponding heterobinuclear oxindolimine Cu(II)Pt(II) complexes (3 and 4), are described. All the isolated complexes were characterized by spectroscopic techniques (UV/Vis, IR, EPR), in addition to elemental analysis and mass spectrometry. Cyclic voltammetry (CV) measurements showed that in all cases, one-electron quasi-reversible waves were observed, and ascribed to the formation of corresponding copper(I) complexes. Additionally, waves related to oxindolimine ligand reduction was verified, and confirmed using analogous oxindolimine-Zn(II) complexes. The Pt(IV/II) reduction, and corresponding oxidation, for complexes 3 and 4 occurred at very close values to those observed for cisplatin. By complementary fluorescence studies, it was shown that glutathione (GSH) cannot reduce any of these complexes, under the experimental conditions (room temperature, phosphate buffer 50mM, pH7.4), using an excess of 20-fold [GSH]. All these complexes showed characteristic EPR spectral profile, with parameters values gǁ>g⊥ suggesting an axially distorted environment around the copper(II) center. Interactions with calf thymus-DNA, monitored by circular dichroism (CD), indicated different effects modulated by the ligands. Finally, the cytotoxicity of each complex was tested toward different tumor cells, in comparison to cisplatin, and low values of IC50 in the range 0.6 to 4.0µM were obtained, after 24 or 48h incubation at 37°C. The obtained results indicate that such complexes can be promising alternative antitumor agents.


Asunto(s)
Cobre , Citotoxinas , ADN/química , Compuestos Organoplatinos , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Bovinos , Línea Celular Tumoral , Citotoxinas/síntesis química , Citotoxinas/química , Citotoxinas/farmacología , Espectroscopía de Resonancia por Spin del Electrón , Ratones , Compuestos Organoplatinos/síntesis química , Compuestos Organoplatinos/química , Compuestos Organoplatinos/farmacología
16.
RGO (Porto Alegre) ; 68: e20200003, 2020. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1091888

RESUMEN

ABSTRACT This study goal is to present a case report of tooth bleaching treatment with the combination of the custom tray and in-office techniques, and to discuss about the considerations for result maintenance. A treatment approach was planned involving exogenous bleaching with custom trays with 7.5% hydrogen peroxide, and in-office bleaching with 35% hydrogen peroxide. The in-office bleaching agent was applied in two 15-minute applications, without led light. The patient was instructed to use the custom trays only a day after, with one drop of the bleaching agent for each tooth space. After the application of the bleaching agent, the patient used the trays for 1 hour per day, continuously for 30 days, 15 days for each arch. Considering the executed treatment approach, we may conclude that when correctly indicated, tooth bleaching with the combination of the in-office and custom trays techniques can be an acceptable choice of treatment, capable of enhancing the smile esthetics with a simple technique that preserves the sound dental structure. The patient should be instructed for the maximum color preservation and esthetic result maintenance, and should be advised that retreatments may become necessary depending on the oral hygiene and frequence of coloured food and drinks intake.


RESUMO O objetivo deste estudo é apresentar um relato de caso em que foi realizado o clareamento dentário com a combinação das técnicas de consultório e de moldeiras e discutir sobre considerações para a manutenção do resultado. Um plano de tratamento foi proposto envolvendo clareamento exógeno com moldeiras com peróxido de hidrogênio 7,5% e o clareamento em consultório com peróxido de hidrogênio 35%. O gel clareador de clareamento em consultório foi aplicado 2 vezes, por 15 minutos cada aplicação, sem luz do tipo Led. A paciente foi orientada a usar as moldeiras customizadas para o clareamento caseiro apenas a partir do dia seguinte, sendo uma gota de gel clareador no espaço equivalente a cada dente. Após a dosagem do gel, ela usou as moldeiras por 1 hora por dia, ininterruptamente por 30 dias, sendo 15 dias para cada arco. Diante do planejamento e terapia executados no caso clínico apresentado, pode-se concluir que a técnica clareadora utilizando a combinação de clareamento em consultório e clareamento com moldeiras customizadas, quando corretamente indicada, pode ser considerada uma alternativa de tratamento bastante satisfatória por ser uma técnica simples capaz de melhorar a estética do sorriso preservando a estrutura dental hígida. O paciente deve ser orientado para a máxima preservação da cor e manutenção estética alcançada, e deve ser ressaltado que retratamentos podem ser necessários dependendo da higiene oral e da frequência de ingestão de alimentos e bebidas corantes.

17.
BEPA, Bol. epidemiol. paul. (Impr.) ; 17(203): 15-24, 2020. graf
Artículo en Portugués | SES-SP, SES SP - Publicações científico-técnicas, SES-SP | ID: biblio-1145580

RESUMEN

O objetivo foi simular cenários de sensibilidade da vigilância da raiva canina em um município de pequeno porte no estado de São Paulo. Clínicos veterinários de São João da Boa Vista-SP foram sensibilizados, dados sobre coletas de amostras de animais antes (2013-2015) e depois (2016-2017) foram coletados e árvores de cenários foram construídas para sensibilidade global e por componente [(1) agressores, (2) atropelados, (3) quadro neurológico e (4) amostras aleatórias]. Probabilidades com IC 95% foram calculadas com vigilância baseada em risco utilizando 31 parâmetros quantitativos. A razão de sensibilidade 1:4, 2:4 e 3:4 mostrou superioridade em todos os anos. A sensibilidade 3 aumentou pós-intervenção e 4 não passou de 1% em qualquer cenário. A priorização do componente 3 melhorou a sensibilidade global e a priorização mais efetiva foi nos componentes 1 e 2. Concluiu-se que a intervenção aumentou a sensibilidade global, amostras aleatórias não melhoraram a vigilância e a priorização de animais agressores e atropelados melhoraram a sensibilidade.


Asunto(s)
Rabia , Árboles , Veterinarios
18.
Int J Biol Macromol ; 52: 107-15, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23010457

RESUMEN

The biopolymer chitosan was chemically modified in two sequences of reactions: (i) immobilization of methyl acrylate followed by cysteamine and (ii) the sequence of immobilization reactions involving ethylene sulfide, methyl acrylate and finally cysteamine. In both cases the pendant chains have attached nitrogen, oxygen and sulfur basic centers. The corresponding structures were characterized through elemental analysis, infrared spectroscopy, nuclear magnetic resonance in the solid state for carbon, thermogravimetry and scanning electron microscopy. The newly synthesized biopolymers have abilities to immobilize and controllably release the non-steroidal drug ibuprofen. The ibuprofen-loaded biomaterials as tablets or as films crosslinked with glutaraldehyde revealed that drug release is pH sensitive. The chemically modified chitosan may allow reduction of drug release in stomach fluids, since the functional groups cause a decrease in swelling rate at pH 1.2, opposite to the behavior that occurs at pH 7.4, that of nutritional fluid, where an increase of the rate of swelling occurs. In such conditions the negatively charge ibuprofen is electrostatically repelled by negative chitosan derivative surfaces.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Quitosano/química , Ibuprofeno/química , Membranas Artificiales , Preparaciones de Acción Retardada/química , Jugo Gástrico/química , Humanos , Concentración de Iones de Hidrógeno
19.
Distúrb. comun ; 30(4): 726-735, dez. 2018. tab, ilus
Artículo en Portugués | LILACS | ID: biblio-995804

RESUMEN

Introdução: A leitura é uma prática importante para a comunicação e compreensão do mundo à nossa volta. Pesquisas apontam que sujeitos surdos apresentam dificuldades significativas na compreensão de leitura. Objetivo: avaliar a compreensão de leitura em profissionais surdos de uma instituição de ensino superior. Método: Casuística: 14 sujeitos adultos surdos, alfabetizados, de ambos os gêneros, na faixa etária entre 20,6 e 42,7 anos. Procedimento: FASE 1: Aplicação do Teste Cloze a partir de um texto jornalístico com aproximadamente 200 palavras, 30 lacunas. FASE 2: Diante dos resultados obtidos, eles foram contatados para desempenhar nova tarefa linguística: leitura seguida de elaboração de resumo escrito do texto original. Seis sujeitos aceitaram participar dessa fase. Critérios de interpretação dos resultados: as respostas do teste Cloze foram categorizadas em: correta, possível, incorreta e em branco. Foi realizada análise descritiva dos dados. Os resumos foram analisados qualitativamente. Resultados: A maioria dos sujeitos obteve pontuação significativamente abaixo do total máximo no teste Cloze. Dos 6 participantes da fase 2, apenas um não apresentou no resumo as informações essenciais do texto. Conclusão: O desempenho em compreensão de leitura, desses sujeitos, é dificultado pelos aspectos formais do código linguístico (morfológicos e sintáticos) e favorecido pelos aspectos semânticos e pragmáticos mobilizados para realização de resumos escritos.


Introduction: Reading is an important practice to communicate and to understand the world around us. Some researches indicate that deaf subjects have significant difficulties in reading comprehension. Objective: To assess reading comprehension in deaf professionals from a higher education institution. Method: Case study: 14 adult subjects, deaf, literate, both male and female, aged between 20.6 and 42.7 years. Procedure: PHASE 1: Application of Cloze Test on a journalistic text with approximately 200 words, 30 blanks. PHASE 2: According to the results obtained by the subjects in Cloze test, they were asked to perform a new linguistic task: reading followed by the preparation of a written summary of the original text. Six subjects accepted to participate in this phase. Criteria for results interpretation: the answers provided in Cloze test were ranked as: correct, possible, incorrect and no answer. A descriptive data analysis was held. The summarized texts were qualitatively analyzed. Results: Most of the subjects obtained scores significantly below compared to the maximum total score of the Cloze test. Of the 6 phase 2 participants, only one did not include essential information in the summary of the text. CONCLUSION: the performance in reading comprehension, in deaf subjects enrolled, is hampered by the formal (morphological and syntactic) aspects of the linguistic code and favored by semantic and pragmatic aspects used to elaborate written summaries.


Introducción: La lectura es una práctica importante para la comunicación y comprensión del mundo a nuestro alrededor. Las investigaciones apuntan que sujetos sordos presentan dificultades significativas en la comprensión de la lectura. OBJETIVO: evaluar la comprensión de lectura en profesionales sordos de una institución de enseñanza superior. Método: Casuística: 14 sujetos adultos sordos, alfabetizados, de ambos géneros, en el grupo de edad entre 20,6 y 42,7 años. Procedimiento: Fase 1: Aplicación del Test Cloze a partir de un texto periodístico con aproximadamente 200 palabras. Fase 2: Ante los resultados obtenidos por los sujetos en el test Cloze, fueron contactados para desempeñar una nueva tarea lingüística: lectura seguida de elaboración de resumen escrito del texto original. Los sujetos aceptados participaron en esa fase. Criterios de interpretación de los resultados: las respuestas del test Cloze se clasificaron en: correcta, posible, incorrecta y en blanco. Se realizó un análisis descriptivo de los datos Los resúmenes se analizaron cualitativamente. Resultados: La mayoría de los sujetos obtuvo una puntuación significativamente por debajo del total máximo (60 puntos) en el test Cloze. De los 6 participantes de la fase 2, sólo uno no presentó en el resumen la información esencial del texto. Conclusión: El desempeño en comprensión de lectura, en los sujetos sordos estudiados, es dificultado por los aspectos formales del código lingüístico (morfológicos y sintácticos) demandados por el test Cloze; y favorecido por los aspectos semánticos y pragmáticos movilizados para la realización de resúmenes escritos.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Lectura , Sordera , Comprensión , Lenguaje
20.
Licere (Online) ; 20(1)mar.2017. tab, ilus, graf
Artículo en Portugués | LILACS | ID: biblio-868188

RESUMEN

O Programa Esporte e Lazer da Cidade (PELC) é uma das políticas do Governo Federal que tem resultado em diversos estudos acadêmicos que procuram entendê-lo melhor. Esta pesquisa teve como objetivo contribuir com estado da arte desta temática procurando estabelecer interfaces entre o PELC e alguns índices de desigualdade social. Para tal foram confrontados os dados sobre os convênios do PELC, o Índice de Desenvolvimento Humano e o Índice de Vulnerabilidade Social. O estudo aponta para a necessidade da existência do IDH enquanto um critério que atribui um peso maior a determinado proponente, porém sugerem que, na atual configuração dos critérios de pontuação dos editais do PELC, este índice pode não assumir a devida importância que poderia ser lhe concedida.


The Program Sporting Goods City ( PELC ) is one of the policies of the Federal Government which has resulted in several academic studies that seek to understand it better . This study aimed to contribute to the art of this theme seeking to establish interfaces between PELC and some indices of social inequality . For such data on covenants PELC were confronted , the Human Development Index and the Social Vulnerability Index . The study points to the need of the HDI existence as a criterion that assigns a greater weight to a particular bidder, but suggest that the current setting of the scoring criteria of PELC the edicts , this index can not assume due importance that could be you granted.


Asunto(s)
Actividades Recreativas
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