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1.
Environ Sci Pollut Res Int ; 29(46): 69949-69966, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35578080

RESUMEN

The study aimed to understand the metal enrichment and toxicity in lower and middle regions of a tropical Mandovi Estuary, revealed metals dilution by coarser intertidal mudflat sediments in the lower estuary (downstream of the fishing jetty-core S). A relatively calm depositional environment prevailed at the middle estuary (core M) and also at the upstream of the jetty of the lower estuary (core L) facilitating deposition and enrichment of Mn and Zn in cores M and Mn, Cu and Co in core L. The distribution of trace metals in sediments was regulated by grain size, total organic carbon and Fe-Mn oxides. The potential contamination index indicated a moderate degree of metal contamination in sediments while the anthropogenic factor showed the signatures of human-induced activities in the enrichment of metals. The sequential extraction of metals showed bioavailability of Mn, Cu, Zn and Co. Fe-Mn oxide and organic/sulphide were key phases for the retention of bioavailable metals. The elevated level of these metals suggested possible toxicity to benthic biota, particularly from Mn (cores L and M) and Co (core L) according to the screening quick reference table.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Carbono , Monitoreo del Ambiente , Estuarios , Sedimentos Geológicos , Humanos , India , Metales Pesados/análisis , Óxidos , Sulfuros , Contaminantes Químicos del Agua/análisis
2.
Adv Mater ; 33(49): e2105254, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34622509

RESUMEN

Prevention of metastatic and local-regional recurrence of cancer after surgery remains difficult. Targeting postsurgical premetastatic niche and microresiduals presents an excellent prospective opportunity but is often challenged by poor therapeutic delivery into minimal residual tumors. Here, an enzymatically transformable polymer-based nanotherapeutic approach is presented that exploits matrix metalloproteinase (MMP) overactivation in tumor-associated tissues to guide the codelivery of colchicine (microtubule-disrupting and anti-inflammatory agent) and marimastat (MMP inhibitor). The dePEGylation of polymersomes catalyzed by MMPs not only exposes the guanidine moiety to improve tissue/cell-targeting/retention to increase bioavailability, but also differentially releases marimastat and colchicine to engage their extracellular (MMPs) and intracellular (microtubules) targets of action, respectively. In primary tumors/overt metastases, the vasculature-specific targeting of nanotherapeutics can function synchronously with the enhanced permeability and retention effect to deter malignant progression of metastatic breast cancer. After the surgical removal of large primary tumors, nanotherapeutic agents are localized in the premetastatic niche and at the site of the postsurgical wound, disrupting the premetastatic microenvironment and eliminating microresiduals, which radically reduces metastatic and local-regional recurrence. The findings suggest that nanotherapeutics can safely widen the therapeutic window to resuscitate colchicine and MMP inhibitors for other inflammatory disorders.


Asunto(s)
Neoplasias de la Mama , Nanomedicina , Neoplasias de la Mama/patología , Colchicina/uso terapéutico , Femenino , Humanos , Inhibidores de la Metaloproteinasa de la Matriz/uso terapéutico , Estudios Prospectivos , Microambiente Tumoral
3.
Philos Trans R Soc Lond B Biol Sci ; 376(1834): 20200177, 2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34365830

RESUMEN

Soil serves as both a 'source' and 'sink' for contaminants. As a source, contaminants are derived from both 'geogenic' and 'anthropogenic' origins. Typically, while some of the inorganic contaminants including potentially toxic elements are derived from geogenic origin (e.g. arsenic and selenium) through weathering of parent materials, the majority of organic (e.g. pesticides and microplastics) as well as inorganic (e.g. lead, cadmium) contaminants are derived from anthropogenic origin. As a sink, soil plays a critical role in the transformation of these contaminants and their subsequent transfer to environmental compartments, including groundwater (e.g. pesticides), surface water (phosphate and nitrate), ocean (e.g. microplastics) and atmosphere (e.g. nitrous oxide emission). A complex transformation process of contaminants in soil involving adsorption, precipitation, redox reactions and biodegradation control the mobility, bioavailability and environmental toxicity of these contaminants. Soil also plays a major role in the decontamination of contaminants, and the 'cleaning' action of soil is controlled primarily by the physico-chemical interactions of contaminants with various soil components, and the biochemical transformations facilitated by soil microorganisms. In this article, we examine the geogenic and anthropogenic sources of contaminants reaching the soil, and discuss the role of soil in the sequestration and decontamination of contaminants in relation to various physico-chemical and microbial transformation reactions of contaminants with various soil components. Finally, we propose future actions that would help to maintain the role of soils in protecting the environment from contaminants and delivering sustainable development goals. This article is part of the theme issue 'The role of soils in delivering Nature's Contributions to People'.


Asunto(s)
Biodegradación Ambiental , Conservación de los Recursos Naturales , Ecosistema , Contaminantes del Suelo/análisis , Suelo/química , Clima
4.
J Cosmet Laser Ther ; 21(2): 84-90, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29737899

RESUMEN

Resveratrol is now being increasingly used in cosmetology and dermatology. This polyphenolic phytoalexin present in large amounts in red grapes and berries has a number of scientifically proven health-promoting properties associated with a positive effect on the cardiovascular system, lowering the concentration of low-density lipoprotein, and the ability to inhibit the cyclooxygenases activity. Additionally, it has antiproliferative, anti-angiogenic, anti-inflammatory, antioxidant, and antimicrobial properties. Its popularity in cosmetology and dermatology is primarily associated with proven ability to penetrate the skin barrier and antiaging activity. It has been shown that formulations with resveratrol can stimulate the proliferation of fibroblasts and contributing to the increase in the concentration of collagen III. Resveratrol has an affinity for the estrogen protein receptors (both ERα and ERß), thereby contributing to the stimulation of collagen types I and II production. Moreover, resveratrol also has the antioxidant properties, thus can protect cells against oxidative damage associated with the effects of free radicals and UV radiation on the skin by reducing the expression of AP-1 and NF-kB factors and it slows down the process of photoaging of the skin. This study reviews literature on the skin care properties of resveratrol and its dermal bioavailability, metabolism, and dermal safety of application.


Asunto(s)
Técnicas Cosméticas , Resveratrol/farmacología , Envejecimiento de la Piel/efectos de los fármacos , Piel/efectos de los fármacos , Acné Vulgar/tratamiento farmacológico , Antioxidantes/farmacología , Humanos , Mediadores de Inflamación/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptores de Estrógenos/efectos de los fármacos , Resveratrol/farmacocinética , Sirtuinas/metabolismo , Preparaciones para Aclaramiento de la Piel/farmacología
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