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1.
Sci Total Environ ; 822: 153584, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35114250

RESUMO

Ongoing monitoring of the distribution and composition of coastal debris is a prerequisite for efficient management and cleanups. Therefore, we conducted a rapid assessment of coastal debris along the 1210 km coastline of Taiwan using a visual estimation method. Forty-nine citizen scientists were intensively trained to correctly identify the volume and types of debris. At 121 sampling locations randomly placed along Taiwan's coastline, the citizen scientists recorded the pollution level and the three most abundant debris types within a 100-m transect during four surveys in 2018-2019. Averaging over the four surveys, the mean amount of coastal debris was estimated to be 406.6 kg/km, and the three most abundant debris types were plastic bottles, foamed plastics, and fishing nets and ropes. Using a statistical test which avoids spatial pseudoreplication, we showed that north-facing coastlines had significantly higher pollution levels than the other coastlines, which we suggest is deposited there during strong winter winds. We also showed that fishery-related debris was a much more important part of coastal debris when the volume of it was determined instead of just the number of items. Mean pollution levels were further associated with wind speed, coastline type, and the distance to presumed pollution sources. Our results compare well with similar surveys conducted in Japan and South Korea. In each country, the debris was highly aggregated, which means it was concentrated in a few highly polluted localities. Therefore, the visual estimation method can effectively guide cleanup efforts to the most polluted areas and also reliably generate long-term monitoring data.


Assuntos
Monitoramento Ambiental , Resíduos , Praias , Monitoramento Ambiental/métodos , Poluição Ambiental , Plásticos , Taiwan , Resíduos/análise
2.
Mar Pollut Bull ; 135: 862-872, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30301108

RESUMO

Man-made coastal debris pollution is a growing concern for Taiwan. In 2004, Taiwanese environmental organizations led by the "Society of Wilderness" began gathering data on 19 categories of debris items collected during cleanup events. We present our analysis of the resulting 12-year dataset collated from 541 events held between October 2004 and December 2016. In total, 904,302 items weighing 131,358.3 kg were collected, and 63.6% and 27.2% of items were made of either plastic or plastic mixed with other materials, respectively. The five most commonly recorded debris categories were plastic shopping bags, plastic bottle caps, disposable tablewares, fishing equipment, and plastic drinking straws. We estimated that during the 12-year period on average between 3.7 and 7.9 million items weighing 560-1110 metric tons polluted Taiwan's coastline. We offer recommendations for improving the quality of data collected during Taiwan's cleanup events and report some policy changes due partly to previous reports of this dataset.


Assuntos
Monitoramento Ambiental/métodos , Resíduos/análise , Poluentes Químicos da Água/análise , Praias , Plásticos/análise , Taiwan , Resíduos/estatística & dados numéricos
3.
Drug Deliv Transl Res ; 7(5): 609-616, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28444555

RESUMO

Needle-free jet injections constitute a crucial method for drug delivery. A novel liquid drug delivery system has been proposed recently, in which pressure atomizes liquid before delivering that atomized liquid to the patient's body; however, the mechanism and efficiency of the system are unclear. This study explored the shot delivery pressure, penetration depth, and cumulative amount of permeation of this system. This system was used to deliver 0.5% (w/v) methylene blue to agarose phantoms at various shot delivery pressures. Shots of methylene blue were also delivered to porcine skin samples at different shot delivery frequencies for light microscopy evaluation. A commercial microneedle array was used for comparing the effectiveness of the skin penetration depths. The array was gently stamped against porcine skin; methylene blue was subsequently applied to the area for different time points, followed by microscopic observations. In vitro skin penetration was tested using static Franz diffusion cells over 8 h. Finally, the feasibility of the system's clinical application was evaluated by analyzing the local analgesic effect in a heat nociceptive animal model. The penetration depths created using 100 shots at 100 psi were similar to those created using the commercial microneedle array for 2 h. Thermal stimulation responses showed that 15 min after diclofenac sodium was delivered by the system, heat nociception was significantly attenuated for 60 min. Our study presents a novel delivery system that may be useful for future clinical applications.


Assuntos
Azul de Metileno/administração & dosagem , Microinjeções/métodos , Animais , Sistemas de Liberação de Medicamentos , Humanos , Injeções a Jato , Modelos Animais , Pele/química , Suínos
4.
PLoS One ; 8(11): e79373, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24260209

RESUMO

BACKGROUND: An increasing awareness of the vulnerability of sharks to exploitation by shark finning has contributed to a growing concern about an unsustainable shark fishery. Taiwan's fleet has the 4th largest shark catch in the world, accounting for almost 6% of the global figures. Revealing the diversity of sharks consumed by Taiwanese is important in designing conservation plans. However, fins make up less than 5% of the total body weight of a shark, and their bodies are sold as filets in the market, making it difficult or impossible to identify species using morphological traits. METHODS: In the present study, we adopted a DNA barcoding technique using a 391-bp fragment of the mitochondrial cytochrome oxidase I (COI) gene to examine the diversity of shark filets and fins collected from markets and restaurants island-wide in Taiwan. RESULTS: Amongst the 548 tissue samples collected and sequenced, 20 major clusters were apparent by phylogenetic analyses, each of them containing individuals belonging to the same species (most with more than 95% bootstrap values), corresponding to 20 species of sharks. Additionally, Alopias pelagicus, Carcharhinus falciformis, Isurus oxyrinchus, and Prionace glauca consisted of 80% of the samples we collected, indicating that these species might be heavily consumed in Taiwan. Approximately 5% of the tissue samples used in this study were identified as species listed in CITES Appendix II, including two species of Sphyrna, C. longimanus and Carcharodon carcharias. CONCLUSION: DNA barcoding provides an alternative method for understanding shark species composition when species-specific data is unavailable. Considering the global population decline, stock assessments of Appendix II species and highly consumed species are needed to accomplish the ultimate goal of shark conservation.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Tubarões/genética , Animais , Carne , Filogenia , Tubarões/classificação , Taiwan
5.
Int J Nanomedicine ; 7: 4861-72, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23028215

RESUMO

BACKGROUND AND METHODS: Chondroitin sulfate-chitosan (ChS-CS) nanoparticles and positively and negatively charged fluorescein isothiocyanate-conjugated bovine serum albumin (FITC-BSA)-loaded ChS-CS nanoparticles were prepared and characterized. The properties of ChS-CS nanoparticles, including cellular uptake, cytotoxicity, and transepithelial transport, as well as findings on field emission-scanning electron microscopy, transmission electron microscopy, and confocal laser scanning microscopy were evaluated in human epithelial colorectal adenocarcinoma (Caco-2) fibroblasts. ChS-CS nanoparticles with a mean particle size of 250 nm and zeta potentials ranging from -30 to +18 mV were prepared using an ionic gelation method. RESULTS: Standard cell viability assays demonstrated that cells incubated with ChS-CS and FITC-BSA-loaded ChS-CS nanoparticles remained more than 95% viable at particle concentrations up to 0.1 mg/mL. Endocytosis of nanoparticles was confirmed by confocal laser scanning microscopy and measured by flow cytometry. Ex vivo transepithelial transport studies using Caco-2 cells indicated that the nanoparticles were effectively transported into Caco-2 cells via endocytosis. The uptake of positively charged FITC-BSA-loaded ChS-CS nanoparticles across the epithelial membrane was more efficient than that of the negatively charged nanoparticles. CONCLUSION: The ChS-CS nanoparticles fabricated in this study were effectively endocytosed by Caco-2 fibroblasts without significant cytotoxicity at high nanoparticle concentrations. ChS-CS nanoparticles represent a potential novel delivery system for the transport of hydrophilic macromolecules.


Assuntos
Membrana Celular/química , Membrana Celular/metabolismo , Quitosana/química , Sulfatos de Condroitina/química , Fluoresceína-5-Isotiocianato/química , Nanocápsulas/química , Soroalbumina Bovina/farmacocinética , Adsorção , Células CACO-2 , Humanos , Eletricidade Estática , Propriedades de Superfície
6.
J Biomater Sci Polym Ed ; 23(7): 973-90, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21549037

RESUMO

We prepared a novel porous gelatin (GEL) sponge which was cross-linked (CL) with a zero-length crosslinker of 2-chloro-1-methylpyridinium iodide (CMPI), and compared CPMI with 1-ethyl-3,3-dimethylaminoproplycarbodiimide (EDC). The ninhydrin assay indicated that the CMPI-CL-GEL sponge had a higher degree of cross-linking than the EDC-CL-GEL sponge at cross-linking saturation. In contrast, the EDC-CL-GEL sponge demonstrated poor water uptake and a much slower enzymatic degradation rate than the CMPI-CL-GEL sponge. Scanning electron microscopy (SEM) images of the gelatin sponge fabricated using a gradient frozen-lyophilization method showed uniformly distributed and interconnected pores. Human 3T3 fibroblasts were successfully seeded onto the scaffolds, and cell proliferation was sustained on all CL-GEL sponges. CMPI-CL-GEL sponges demonstrated significantly increased cell numbers after day 1, and cell numbers steadily rose from day 1 to 12. Meanwhile, the CMPI-CL-GEL sponge had a higher cell number than the EDC-CL-GEL sponge (P < 0.05) by day 4. In vitro studies with 3T3 fibroblasts demonstrated an increased cell viability for those cells grown on sponges cross-linked with CMPI compared to those cross-linked with EDC. SEM images revealed attachment and spreading of cells, the CMPI-CL-GEL sponges had more cells that had elongated, migrated, and formed interconnected networks with neighboring cells.


Assuntos
Reagentes de Ligações Cruzadas/química , Gelatina/química , Compostos de Piridínio/química , Alicerces Teciduais/química , Animais , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Colagenases/química , Fibroblastos/fisiologia , Fibroblastos/ultraestrutura , Humanos , Camundongos , Estrutura Molecular , Ninidrina/química , Porosidade , Pele , Propriedades de Superfície , Suínos , Fatores de Tempo , Água/química
7.
Int J Nanomedicine ; 6: 2403-17, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22072876

RESUMO

Fluorescein isothiocyanate-conjugated bovine serum albumin (FITC-BSA)-loaded polyethylene glycol (PEG)-modified liposomes and lipoparticles with high protein entrapment were developed. The lipid formula of the liposomes contained PEGylated lipids and unsaturated fatty acids for enhancing membrane fluidity and effective delivery into cells. The preparation techniques, lipid content, and PEG-modified lipoparticle ratios were evaluated. The PEG-modified lipoparticles prepared by ethanol injection extrusion (100 nm pore size) achieve a population of blank liposomes with a mean size of 125 ± 2.3 nm and a zeta potential of -12.4 ± 1.5 mV. The average particle size of the PEG-modified lipoparticles was 133.7 ± 8.6 nm with a zeta potential of +13.3 mV. Lipoparticle conformation was determined using transmission electron microscopy and field-emission scanning electron microscopy. The FITC-BSA encapsulation efficiency was dramatically increased from 19.0% for liposomes to 59.7% for lipoparticles. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) results confirmed the preparation process, and an 8-hour leaching test did not harm the protein structure. Once prepared, the physical and chemical stability of the PEG-modified lipoparticle formulations was satisfactory over 90 days. In vitro retention tests indicated that the 50% retention time for the protein-containing lipoparticles was 7.9 hours, substantially longer than the liposomes at 3.3 hours. A Caco-2 cell model was used for evaluating the cytotoxicity and cell uptake efficiency of the PEG-modified lipoparticles. At a lipid content below 0.25 mM, neither the liposomes nor the lipoparticles caused significant cellular cytotoxicity (P < 0.01) and FITC-BSA was significantly taken up into cells within 60 minutes (P < 0.01).


Assuntos
Lipossomos/química , Nanopartículas/química , Soroalbumina Bovina/química , Soroalbumina Bovina/farmacocinética , Animais , Células CACO-2 , Bovinos , Sobrevivência Celular , Ácidos Docosa-Hexaenoicos/química , Estabilidade de Medicamentos , Eletroforese em Gel de Poliacrilamida , Citometria de Fluxo , Fluoresceína-5-Isotiocianato/química , Fluoresceína-5-Isotiocianato/farmacocinética , Liofilização , Humanos , Microscopia Eletrônica , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Estabilidade Proteica , Estatísticas não Paramétricas
8.
Acta Biomater ; 7(10): 3804-12, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21742066

RESUMO

In this study, the potential of chondroitin sulfate (ChS)-chitosan (CS) nanoparticles (NPs) for the delivery of proteins was investigated. ChS-CS NPs were prepared by ionic cross-linking of CS solution with ChS. The aggregation line, particle size and zeta potential were investigated as a function of the pH, weight ratio and concentration. The water content and formation yield of the NPs were measured by gravimetry. Results indicated that ChS-CS NPs showed a higher degree of ionic cross-linking and formation yield than sodium tripolyphosphate-CS NPs. Fluorescein isothiocyanate conjugate bovine serum albumin (FITC-BSA), a model protein drug, was incorporated into the ChS-CS NPs. The encapsulation efficiency was obviously increased with the increase in initial FITC-BSA concentration and was as high as 90%. In vitro release studies of ChS-CS NPs showed a small burst effect following a continued and controlled release. Cytotoxicity tests with Caco-2 cells showed no toxic effects of ChS-CS NPs. The ex vivo cellular uptake studies using Caco-2 and HEK-293 cells indicated that NPs were found to be endocytosed into the cells. In conclusion, ChS-CS NPs are a potential new delivery system for the transport of hydrophilic compounds such as proteins.


Assuntos
Quitosana/síntese química , Sulfatos de Condroitina/síntese química , Fluoresceína-5-Isotiocianato/análogos & derivados , Nanopartículas/química , Soroalbumina Bovina/química , Animais , Células CACO-2 , Bovinos , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quitosana/farmacologia , Sulfatos de Condroitina/farmacologia , Fluoresceína-5-Isotiocianato/química , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Cinética , Microscopia Confocal , Peso Molecular , Nanopartículas/ultraestrutura , Tamanho da Partícula , Soroalbumina Bovina/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Água/química
9.
Artigo em Inglês | MEDLINE | ID: mdl-15282091

RESUMO

A rapid immunochromatographic assay was developed to detect botulinum neurotoxin type B (BoNT/B). The assay was based on the sandwich format using polyclonal antibody (Pab). The thiophilic gel purified anti-BoNT/B Pab was immobilized to a defined detection zone on a porous nitrocellulose membrane and conjugated to colloidal gold particles that served as a detection reagent. The BoNT/B-containing sample was added to the membrane and allowed to react with Pab-coated particles. The mixture was then passed along the porous membrane by capillary action past the Pab in the detection zone, which will bind the particles that had BoNT/B bound to their surface, giving a red colour within this detection zone with an intensity proportional to BoNT/B concentration. In the absence of BoNT/B, no immunogold was bound to the solid-phase antibody. With this method, 50 ng/ml of BoNT/B was detected in less than 10 min. The assay sensitivity can be increased by silver enhancement to 50 pg/ml. The developed BoNT/B assay also showed no cross reaction to type A neurotoxin (BoNT/A) and type E neurotoxin (BoNT/E).


Assuntos
Toxinas Botulínicas/análise , Cromatografia Líquida/métodos , Coloides/química , Ouro/química , Toxinas Botulínicas Tipo A , Reações Cruzadas , Sensibilidade e Especificidade
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