Progress in inorganic nanomaterials for photothermal therapy of cancer / 肿瘤

Traditional methods of cancer treatment such as surgical resection, chemotherapy and radiotherapy have certain limitations, and their treatment effects are not always satisfactory. As a new cancer treatment method, photothermal therapy based on nanomaterials has attracted people's attention due to its characteristics of minimally invasive, high efficiency, low side effects and inhibition of cancer metastasis. At present, there are a variety of inorganic or organic nanomaterials used in the field of photothermal cancer treatment, and have shown great application prospects. In this paper, the advantages and disadvantages of a variety of inorganic nanomaterials for photothermal therapy as well as their research progress are reviewed.

Inspección preliminar de algunas características de toxicidad en el agua potable domiciliaria, Bogotá y Soacha, 2012 / Preliminary survey to detect toxic substances in domestic potable water, Bogotá and Soacha, 2012

Introducción. La distribución y el almacenamiento del agua después de su potabilización, pueden originar cambios significativos en su calidad, por lo que es necesario conocer las características finales del agua domiciliaria que consumen los usuarios. Objetivo. Evaluar de forma preliminar las sustancias químicas tóxicas en el agua de tanques y grifos de viviendas abastecidas por el acueducto de Bogotá. Materiales y métodos. Se hizo un estudio descriptivo en 26 viviendas localizadas en Bogotá y Soacha. Se hicieron dos muestreos: uno en época de lluvias y otro en temporada seca, y en ambos se aplicó una encuesta y se recolectaron muestras de agua de los tanques de almacenamiento y los grifos. Las muestras se sometieron a ensayos fisicoquímicos básicos, a una prueba de tamización de sustancias orgánicas e inorgánicas, y a pruebas de determinación de metales pesados y de residuos de plaguicidas organofosforados y carbamatos. Resultados. La conductividad, el color y los nitratos presentaron valores permisibles; el pH y la turbiedad tuvieron una ligera tendencia a presentar niveles altos y, el cloro residual, niveles bajos. Hubo trazas de aluminio en el 94 % de las muestras. En el período seco, 8 % de las muestras presentó compuestos orgánicos y, en el período lluvioso, 66,7 %. Solo hubo un resultado positivo para las sustancias inorgánicas. En el 11,5 % de las viviendas, el nivel de riesgo fue medio, en el 61,5 %, bajo, y en el 27 % no se registró riesgo. Conclusiones. Se evidenció deterioro de la calidad del agua domiciliaria debido a la presencia de sustancias orgánicas en tanques y sobre todo en las redes, presumiblemente a causa de la formación de biopelículas o a la presencia de polímeros orgánicos. Los niveles de aluminio cercanos al máximo aceptable pueden explicarse por los remanentes de los coagulantes utilizados durante el tratamiento.

Introduction: Significant alterations may be found in the water of Bogotá´s water supply system after its purification, specifically during its distribution and storage in home reservoirs, which makes it necessary to study the final quality of the domiciliary water consumed by users. Objective: To conduct a preliminary study of toxic chemical substances in the water supplied by Bogotá´s water supply system in samples obtained from residential reservoirs and faucets. Materials and methods: Descriptive study made in 26 homes located in Bogotá and Soacha. Two samplings were done during different seasons, each including a survey and the collection of water samples from domiciliary storage tanks and faucets. Samples were analyzed for basic physicochemical parameters, a screening test for organic and inorganic substances and the determination of heavy metals and residues of organophosphate pesticides and/or carbamates. Results: Values obtained for conductivity, color and nitrates were acceptable, pH and turbidity were slightly high while residual chlorine levels were low; aluminum traces were found in 94% of the samples; 8% of the samples analyzed during the dry season showed organic compounds, compared to 66.7% during the rainy season, and just one positive result was obtained for inorganic compounds. Consequently, a medium risk level was observed in 11.5% of homes, low risk in 61.5% and no risk in 27.0%. Conclusion: The evidence showed deterioration of the domiciliary water by organic substances present in the reservoirs as well as in the water supply piping, probably caused by the formation of biofilms or organic polymers. Aluminum levels close to the top permissible limit can be explained by the presence of residual coagulants used during water treatment.

Inorganic elemental analysis and identification of residual monomers released from different glass ionomer cements in cell culture medium / Análise elementar inorgânica e identificação de monômeros residuais orgânicos liberados por diferentes cimentos de ionômero de vidro

Introduction: Glass ionomer cements (GICs) release inorganic elements and organic residual monomers with the potential for deleterious effects on pulp cells. Objective: To identify and quantify inorganic elements present in different GICs and released components from these materials in cell culture medium. Material and Method: Samples of two resin-modified GICs for base/liner (Vitrebond and Fuji Lining LC), two resin-modified restorative GICs (Vitremer and Fuji II LC) and two conventional restorative GICs (Ketac Fil Plus and Ketac Molar Easymix) were prepared and analyzed by Energy-Dispersive X-Ray Fluorescence Spectrometry (EDXRF). Extracts of these materials were obtained by immersion of each sample in separate containers of DMEM for 24 h (total surface-liquid ratio = 45.7 mm²/mL). The extracts were analyzed by EDXRF and Gas Chromatography-Mass Spectrometry (GC-MS). Result: Higher percentages of strontium, silicon and aluminum were identified in Vitrebond, Vitremer, Fuji Lining LC, Fuji II LC, and Ketac Fil Plus, while zinc was detected only in Vitrebond. Ketac Molar Easymix presented a greater atomic composition of lanthanum, calcium, aluminum and silicon. Strontium was detected in the extracts from all materials except Ketac Molar Easymix; calcium was present in extracts from Ketac Fil Plus; zinc only in Vitrebond; and silicon in Fuji II LC extract. The analysis by GC-MS detected 2-hydroxyethyl-methacrylate (HEMA) in the extracts from all resin-modified GICs, and iodine benzene was detected only in the Vitrebond extract. Conclusion: Of the GICs sampled, Vitrebond released the highest number of components with cytotoxic potential.

Introdução: Os cimentos de ionômero de vidro (CIVs) liberam elementos inorgânicos e monômeros orgânicos residuais que têm o potencial de causar efeitos deletérios sobre as células pulpares. Objetivo: Identificar e quantificar os elementos inorgânicos presentes em diferentes CIVs, bem como os componentes liberados por estes materiais em meio de cultura celular. Material e Método: Espécimes cilindricos de dois CIVs modificados por resina para base/forramento (Vitrebond e Fuji Lining LC), dois CIVs modificados por resina restauradores (Vitremer e Fuji II LC) e dois CIVs convencionais restauradores (Ketac Fil Plus e Ketac Molar Easymix) foram preparados e analisados por Espectrometria de Fluorescência de Raios X por Energia Dispersiva (EDXRF). Em seguida, extratos de 24h desses materiais foram obtidos e analisados por EDXRF e por Cromatografia Gasosa/Espectrometria de Massa (CG/EM). Resultado: Os elementos inorgânicos identificados em maior porcentagem nos CIVs Vitrebond, Fuji Lining LC, Vitremer, Fuji II LC e Ketac Fil Plus foram estrôncio, silício e alumínio, enquanto o zinco foi detectado apenas no Vitrebond. O Ketac Molar Easymix apresentou maior porcentagem dos elementos lantânio, cálcio, alumínio e silício. Estrôncio foi detectado nos extratos de todos os materiais, exceto no Ketac Molar Easymix; cálcio estava presente no extrato do Ketac Fil Plus; zinco apenas no Vitrebond; e silício no extrato do Fuji II LC . O HEMA foi identificado nos extratos de todos os CIVs modificados por resina, e o iodobenzeno, somente no Vitrebond. Conclusão: Entre os CIVs estudados, o Vitrebond é o que libera mais componentes com potencial citotóxico.

Estudo comparativo in vitro das estruturas orgânicas e inorgânicas da dentina saudável e esclerosada humana e bovina: nanodureza, concentração de Ca e P e análise morfológica / In vitro comparative study of organic and inorganic components analysis of health and sclerotic human and bovine dentin: nanohardness, Ca and P concentration and morphological analysis

A dentina esclerosada é um substrato comumente encontrado em pacientes idosos. No entanto, existem poucos estudos comparativos entre dentina humana e bovina esclerosadas. O objetivo deste estudo foi comparar os componentes inorgânicos e orgânicos da dentina saudável e esclerosada humana e bovina, através de cinco parâmetros: nanodureza, módulo de elasticidade, análise quantitativa da concentração de Cálcio (Ca) e Fósforo (P), densidade tubular e morfologia do colágeno. Trinta dentes humanos e 30 bovinos foram distribuídos em 4 grupos experimentais (n=15 por grupo): dentina humana saudável (DHS), esclerosada humana (DEH), bovina saudável (DBS), e bovina esclerosada (DBE). Os dentes saudáveis foram preparados na mesma altura e inclinação dos dentes esclerosados expondo níveis similares da dentina e obtendo fragmentos com 2mm de espessura. Foram realizadas 3 medições por espécime em 3 áreas pré determinadas de dentina intertubular com a utilização do Nanoindentador (carga de 500N por 5 s). Cinco espécimes de cada grupo foram preparados para Microscopia Eletrônica de Varredura (MEV). Com o auxílio da Energia Dispersiva por Raios-X EDX foram obtidos os valores (em percentagem) das concentrações de Ca e P e calculada a relação Ca:P. A contagem dos túbulos por área foi realizada em todas as eletromicrografias. Após descalcificação e preparo, o restante dos espécimes foi analisado em Microscopia Eletrônica de Transmissão (MET)...

The sclerotic dentin has been commonly found in elderly patients. However, there are scarce reports in the literature comparing on the use of human and bovine sclerotic dentins. The objective of this study was to compare inorganic and organic components of healthy and sclerotic dentins from human and bovine. Five parameters were analyzed: nanohardness, elastic modulus, quantitative analysis of Calcium (Ca) and Phosphorous (P) concentrations, tubular density and ultrastructural morphology. Thirty human teeth plus 30 bovine teeth were distributed in 4 experimental groups (n=15 per group): human healthy dentin (HHD), human sclerotic dentin (HSD), bovine healthy dentin (BHD) and bovine sclerotic dentin (BSD). Healthy teeth were cut in the same level and inclination of the sclerotic superficial dentins. The nanohardness and elastic modulus (GPa) of three pre determined areas of each exposed dentin was measured using a nanoindenter (500N for 5s). Five samples of each group were prepared for scanning electron microscopy (SEM) examination. Energy Dispersive X-ray (EDX) was used for obtaining the Ca/P ratio. The tubular density was obtained by counting the tubules in scanning electron micrographs taken in the same magnification and work distance...