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1.
Conserv Biol ; 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35338514

RESUMO

Resolving trade-offs between economic development and biodiversity conservation needs is one of the defining issues of our time. This is crucial in currently developing countries and in particularly sensitive systems harboring high biodiversity. Yet, such a task can be challenging as human activities may have complex effects on biodiversity. Here we assessed the effects of intense economic development on different components of biodiversity using Hainan Island (South China) as model. This highly biodiverse tropical island has experienced intense economic development and extensive forest to agriculture conversion and urbanization across the last two decades. We characterized three main habitat clusters, based on local land use, climate and economic changes across 145 grids (10×10 km), and estimated avian biodiversity responses between 1998 and 2013. We recorded ongoing taxonomic biotic homogenization at the regional scale (i.e., the whole island), evidenced by decreasing differences between traditional and directional alpha diversity. Communities became overall phylogenetically clustered and functionally overdispersed. Biodiversity's priority effects were pervasive, with less diverse communities showing positive and more diverse communities showing negative biodiversity changes. Finally, at the local scale, different economic and environmental indicators showed complex and divergent effects across habitat clusters and biodiversity components. These effects were only partially ameliorated within a newly established Ecological Function Conservation Area in the mountainous central part of the island. Thus, our results depict complex effects of economic development on different biodiversity dimensions in different areas of the island with different land uses and protection regimes, and between local and regional spatial scales. Profound ecosystem damage associated with economic development was partially averted, probably due to enhanced biodiversity conservation policies and law enforcement, yet at the cost of regional-scale biotic homogenization and local-scale biodiversity loss. This article is protected by copyright. All rights reserved.

2.
Environ Geochem Health ; 44(12): 4423-4436, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35098416

RESUMO

Severe outcome particularly death is the largest burden of COVID-19. Clinical observations showed preliminary data that deficiency in certain trace elements, essential for the normal activity of immune system, may be associated with worse COVID-19 outcome. Relevant study of environmental epidemiology has yet to be explored. We investigated the geographical association between concentrations of Se, Zn, Fe and Cu in surface soils and case fatality rate of COVID-19 in USA. Two sets of database, including epidemiological data of COVID-19 (including case fatality rate, from the University of John Hopkinson) and geochemical concentration data of Se, Zn, Fe and Cu in surface soils (from the National Geochemical Survey), were mapped according to geographical location at the county level across conterminous USA. Characteristics of population, socio-demographics and residential environment by county were also collected. Seven cross-sectional sampling dates, with a 4-week interval between adjacent dates, constructed an observational investigation over 24 weeks from October 8, 2020, to March 25, 2021. Multivariable fractional (logit) outcome regression analyses were used to assess the association with adjustment for potential confounding factors. In USA counties with the lowest concentration of Zn, the case fatality rate of COVID-19 was the highest, after adjustment for other influencing factors. Associations of Se, Fe and Cu with case fatality rate of COVID-19 were either inconsistent over time or disappeared after adjustment for Zn. Our large study provides epidemiological evidence suggesting an association of Zn with COVID-19 severity, suggesting Zn deficiency should be avoided.


Assuntos
COVID-19 , Selênio , Oligoelementos , Humanos , Zinco/análise , Cobre/análise , Oligoelementos/análise , Selênio/análise , Ferro/análise , Estudos Transversais , Solo
3.
Nanomedicine ; 21: 102075, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31377378

RESUMO

To improve Biopharmaceutics Classification System class IV drug bioavailability, mucus and underlying intestinal epithelial barriers must be overcome. Hydrophilic nanoparticle coatings may hinder cellular uptake and transport. We integrated hydrophilic, detachable poly(N-(2-hydroxypropyl) methacrylamide) with vitamin B12-modified chitosan into lipid polymeric nanoparticles (H/VC-LPNs) to enhance mucus penetration, intracellular uptake, and transepithelial absorption. Multiple particle tracking revealed accelerated mucus diffusion into porcine mucus in vitro. The nanoparticles increased uptake and intracellular distribution in Caco-2 cells, which may involve intrinsic factor receptor-mediated endocytosis and intercellular tight junctions. Integration of improved mucus penetration and intracellular absorption was confirmed by in vitro internalization kinetics in HT29-MTX/Caco-2 co-cultures and in vivo distribution, transport, and mouse Peyer's patch absorption. H/VC-LPNs substantially increased curcumin bioavailability in rats. A nanocarrier with a dissociable shell, receptor-mediated intracellular penetration, and paracellular transport may be promising for oral curcumin delivery. This study identified the key factors involved in oral bioavailability enhancement.


Assuntos
Sistemas de Liberação de Medicamentos , Mucosa Intestinal/metabolismo , Lipídeos , Nanopartículas/química , Nódulos Linfáticos Agregados/metabolismo , Administração Oral , Animais , Transporte Biológico Ativo , Células CACO-2 , Quitosana/química , Quitosana/farmacocinética , Quitosana/farmacologia , Feminino , Humanos , Lipídeos/química , Lipídeos/farmacocinética , Lipídeos/farmacologia , Camundongos , Ratos , Vitamina B 12/química , Vitamina B 12/farmacocinética , Vitamina B 12/farmacologia
4.
Int J Nanomedicine ; 14: 3311-3330, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190795

RESUMO

Background: Oral route of administration is preferred for treating breast cancer, especially when continued disease management with good tolerability is required; however, orally administered chemotherapeutics combined with near-infrared (NIR) dyes are hindered by the low bioavailability, insufficient for the desired therapeutic efficacy. In this study, we developed a hybrid self-microemulsifying drug delivery system for co-loading curcumin-phospholipid complex and NIR dye IR780 (CUR/IR780@SMEDDS), to achieve combined phototherapeutic and chemotherapeutic effects against lung metastasis of breast cancer. Methods: CUR/IR780@SMEDDS were characterized. The efficacy against breast cancer metastasis was evaluated by photothermal and photodynamic assessment, cytotoxicity, invasion, and migration in metastatic 4T1 breast cancer cells in vitro, and in vivo oral bioavailability study in rats and pharmacodynamics studies in tumor-bearing nude mice. Results: CUR/IR780@SMEDDS improved oral bioavailability of curcumin and IR780 in rats compared with curcumin and IR780 suspensions. CUR/IR780@SMEDDS exhibited remarkable photothermal and photodynamic effects in vitro. In metastatic 4T1 breast cancer cells, CUR/IR780@SMEDDS combined with localized NIR laser irradiation induced significant cytotoxicity and inhibited invasion and migration of 4T1 cells, an outcome attributable to cumulative effects of IR780-induced hyperthermia and pharmacological effects of curcumin. In orthotopic 4T1 tumor-bearing nude mice, combination of oral administration of CUR/IR780@SMEDDS with local NIR laser irradiation inhibited tumor progression and suppressed lung metastasis.


Assuntos
Neoplasias da Mama/patologia , Corantes/administração & dosagem , Curcumina/administração & dosagem , Curcumina/uso terapêutico , Sistemas de Liberação de Medicamentos , Indóis/administração & dosagem , Neoplasias Pulmonares/secundário , Fosfolipídeos/química , Administração Oral , Animais , Linhagem Celular Tumoral , Curcumina/farmacologia , Feminino , Humanos , Hipertermia Induzida , Camundongos Nus , Ratos Sprague-Dawley
5.
J Nanobiotechnology ; 16(1): 64, 2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30176941

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a chronic disease that causes excessive hepatic lipid accumulation. Reducing hepatic lipid deposition is a key issue in treatment and inhibition of NAFLD evolution. Silymarin is a potent hepatoprotective agent; however, it has low oral bioavailability due to its poor aqueous solubility and low membrane permeability. Unfortunately, few studies have addressed the development of convenient oral nanocarriers that can efficiently deliver silymarin to the liver and enhance its lipid-lowering effect. We designed silymarin-loaded lipid polymer hybrid nanoparticles containing chitosan (CS-LPNs) to improve silymarin bioavailability and evaluated their lipid-lowering effect in adiponutrin/patatin-like phospholipase-3 I148M transgenic mice, an NAFLD model. RESULTS: Compared to chitosan-free nanoparticles, CS-LPNs showed 1.92-fold higher uptake by fatty liver cells. Additionally, CS-LPNs significantly reduced TG levels in fatty liver cells in an in vitro lipid deposition assay, suggesting their potential lipid-lowering effects. The oral bioavailability of silymarin from CS-LPNs was 14.38-fold higher than that from suspensions in rats. Moreover, compared with chitosan-free nanoparticles, CS-LPNs effectively reduced blood lipid levels (TG), improved liver function (AST and ALT), and reduced lipid accumulation in the livers of mice in vivo. Reduced macrovesicular steatosis in pathological tissue after CS-LPN treatment indicated their protective effect against liver steatosis in NAFLD. CONCLUSIONS: CS-LPNs enhanced oral delivery of silymarin and exhibited a desirable lipid-lowering effect in a mouse model. These findings suggest that CS-LPNs may be a promising oral nanocarrier for NAFLD therapeutics.


Assuntos
Quitosana/química , Ácido Láctico/química , Lipídeos/química , Nanopartículas/química , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Ácido Poliglicólico/química , Silimarina/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Transporte Biológico , Células CACO-2 , Preparações de Ação Retardada/síntese química , Portadores de Fármacos/síntese química , Portadores de Fármacos/metabolismo , Portadores de Fármacos/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Células Hep G2 , Humanos , Fígado , Masculino , Camundongos , Camundongos Transgênicos , Estrutura Molecular , Nanopartículas/administração & dosagem , Nanopartículas/metabolismo , Nanopartículas/uso terapêutico , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Wistar , Silimarina/administração & dosagem , Silimarina/uso terapêutico , Propriedades de Superfície
6.
IEEE Trans Vis Comput Graph ; 24(6): 1969-1982, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28500004

RESUMO

In this work, we propose an original scheme for generic content-based retrieval of marker-based motion capture data. It works on motion capture data of arbitrary subject types and arbitrary marker attachment and labelling conventions. Specifically, we propose a novel motion signature to statistically describe both the high-level and the low-level morphological and kinematic characteristics of a motion capture sequence, and conduct the content-based retrieval by computing and ordering the motion signature distance between the query and every item in the database. The distance between two motion signatures is computed by a weighted sum of differences in separate features contained in them. For maximum retrieval performance, we propose a method to pre-learn an optimal set of weights for each type of motion in the database through biased discriminant analysis, and adaptively choose a good set of weights for any given query at the run time. Excellence of the proposed scheme is experimentally demonstrated on various data sets and performance metrics.

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