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1.
Mar Drugs ; 19(12)2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34940665

RESUMO

Peloids have been used for therapeutic purposes since time immemorial, mainly in the treatment of locomotor system pathologies and dermatology. Their effects are attributed to their components, i.e., to the properties and action of mineral waters, clays, and their biological fraction, which may be made up of microalgae, cyanobacteria, and other organisms present in water and clays. There are many studies on the therapeutic use of peloids made with microalgae/cyanobacteria, but very little research has been done on dermocosmetic applications. Such research demonstrates their potential as soothing, regenerating, antioxidant, anti-inflammatory, and antimicrobial agents. In this work, a method for the manufacture of a dermocosmetic peloid is presented based on the experience of the authors and existing publications, with indications for its characterization and study of its efficacy.


Assuntos
Argila , Microalgas , Águas Minerais , Animais , Organismos Aquáticos , Cosméticos , Peloterapia
2.
Ind Eng Chem Res ; 60(51): 18791-18805, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34992332

RESUMO

Porous SiO2 nanospheres were modified with different loadings of ZrO2 to obtain catalysts with a Si/Zr molar ratio from 2.5 to 30. These materials were characterized by X-ray diffraction, transmission and scanning electron microscopies, N2 adsorption-desorption at -196 °C, X-ray photoelectron spectroscopy and pyridine and 2-6-dimethylpyridine thermoprogrammed desorption. The characterization of these catalysts has revealed that a high proportion of Zr favors the formation of Lewis acid sites, which are implied in catalytic transfer hydrogenation processes, whereas the low Brönsted acidity promotes a dehydration reaction, being possible to give rise to a large variety of products from furfural through consecutive reactions, such as furfuryl alcohol, i-propyl furfuryl ether, i-propyl levulinate, and γ-valerolactone, in a range of temperature of 110-170 °C and 1-6 h of reaction.

3.
Molecules ; 25(17)2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32882899

RESUMO

Although chitin is of the most available biopolymers on Earth its uses and applications are limited due to its low solubility. The deacetylation of chitin leads to chitosan. This biopolymer, composed of randomly distributed ß-(1-4)-linked D-units, has better physicochemical properties due to the facts that it is possible to dissolve this biopolymer under acidic conditions, it can adopt several conformations or structures and it can be functionalized with a wide range of functional groups to modulate its superficial composition to a specific application. Chitosan is considered a highly biocompatible biopolymer due to its biodegradability, bioadhesivity and bioactivity in such a way this biopolymer displays a wide range of applications. Thus, chitosan is a promising biopolymer for numerous applications in the biomedical field (skin, bone, tissue engineering, artificial kidneys, nerves, livers, wound healing). This biopolymer is also employed to trap both organic compounds and dyes or for the selective separation of binary mixtures. In addition, chitosan can also be used as catalyst or can be used as starting molecule to obtain high added value products. Considering these premises, this review is focused on the structure and modification of chitosan as well as its uses and applications.


Assuntos
Quitosana/química , Acetilação , Animais , Materiais Biocompatíveis/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Hidrogéis/química , Engenharia Tecidual
4.
Toxins (Basel) ; 7(10): 3977-88, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26426051

RESUMO

High accumulations of phytoplankton species that produce toxins are referred to as harmful algal blooms (HABs). HABs represent one of the most important sources of contamination in marine environments, as well as a serious threat to public health, fisheries, aquaculture-based industries, and tourism. Therefore, methods effectively controlling HABs with minimal impact on marine ecology are required. Marine dinoflagellates of the genera Dinophysis and Prorocentrum are representative producers of okadaic acid (OA) and dinophysistoxins responsible for the diarrhetic shellfish poisoning (DSP) which is a human intoxication caused by the consumption of shellfish that bioaccumulate those toxins. In this work we explore the use of natural clay for removing Prorocentrum lima. We evaluate the adsorption properties of clays in seawater containing the dinoflagellates. The experimental results confirmed the cell removal through the flocculation of algal and mineral particles leading to the formation of aggregates, which rapidly settle and further entrain cells during their descent. Moreover, the microscopy images of the samples enable one to observe the clays in aggregates of two or more cells where the mineral particles were bound to the outer membranes of the dinoflagellates. Therefore, this preliminary data offers promising results to use these clays for the mitigation of HABs.


Assuntos
Silicatos de Alumínio/química , Bentonita/química , Dinoflagellida/isolamento & purificação , Caulim/química , Água do Mar/parasitologia , Poluentes da Água/isolamento & purificação , Adsorção , Argila , Floculação , Proliferação Nociva de Algas , Tamanho da Partícula , Propriedades de Superfície
5.
Acta méd. colomb ; 21(4): 158-61, jul.-ago. 1996. tab
Artigo em Espanhol | LILACS | ID: lil-183326

RESUMO

Objetivo : estandarizar valores de referencia de CD4/CD3 y CD8/CD3 por citometría de flujo (FACS) y usar estos valores de referencia para el monitoreo de células T CD4(+) en pacientes con infección por VIH, y comparar la técnica de FACS con la de inmunofluorescencia. Sujetos de Estudio : cien adultos clínicamente sanos y serológicamente aptos para ser donantes de sangre entre los 18 y 45 años de edad. La toma de la muestra fue realizada entre las 08:00 a.m. y las 10:00 a.m. Métodos : citometría de flujo para recuentos absolutos de CD4, CD8 y CD3 e inmunofluorescencia directa (IFD) para CD4 y CD8. Resulatdos : los valores absolutos de CD4/CD3 variaron entre 338 y 1.548, y los de CD8/CD3 entre 800 y 1.119. La relación CD4/CD8 osciló en un amplio rango, entre 0.69 a 2.5. Al comparar ambas técnicas se observó una gran variación en los resultados. Conclusiones : los rangos de variación para CD4/CD3 y CD8/CD3 son muy amplios en la población normal estudiada y son más bajos que los informados en la literatura. No son comparables los valores obtenidos por técnicas de FACS e IFD.


Assuntos
Humanos , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , /métodos , Citometria de Fluxo/métodos , Citometria de Fluxo/tendências
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