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1.
Int J Mol Sci ; 24(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36614226

RESUMO

Major latex-like proteins (MLPs) play crucial roles in abiotic and biotic stresses. However, little was known about this gene family in cucumbers. In this study, a total of 37 putative cucumber MLP genes were identified on a genome-wide level and classified into three groups by sequence homologous comparison with Arabidopsis thaliana. Chromosome mapping suggested that only tandem duplication occurred in evolution. The multiple regulatory cis-elements related to stress, hormone, light and growth response were found in the promoter region of these CsMLP genes, indicating that CsMLPs might be widely involved in the process of plant growth, development and various stress conditions. Transcriptome analysis indicated a strong reprogramming of MLPs expression in response to Phytophthora melonis infection in cucumber. Knockdown of CsMLP1 reduced the P. melonis tolerance, while transient overexpression of CsMLP1 improved disease tolerance in cucumber. Conversely, the silence of CsMLP5 decreased the lesion area caused by P. melonis in the cotyledons, and overexpression of CsMLP5 promoted lesion expansion. Taken together, our results provide a comprehensive basis for further mining the function of CsMLP members and will also be significant for elucidating the evolutionary relationship in cucumber.


Assuntos
Arabidopsis , Cucumis sativus , Phytophthora , Cucumis sativus/genética , Cucumis sativus/metabolismo , Látex/metabolismo , Genoma de Planta , Phytophthora/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Filogenia , Regulação da Expressão Gênica de Plantas
2.
J Nanobiotechnology ; 20(1): 471, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335352

RESUMO

Ovarian cancer is a highly fatal gynecologic malignancy worldwide. Chemotherapy remains the primary modality both for primary and maintenance treatments of ovarian cancer. However, the progress in developing chemotherapeutic agents for ovarian cancer has been slow in the past 20 years. Thus, new and effective chemotherapeutic drugs are urgently needed for ovarian cancer treatment. A reduction-responsive synergetic delivery strategy (PSSP@ART-ISMN) with co-delivery of artesunate and isosorbide 5-mononitrate was investigated in this research study. PSSP@ART-ISMN had various effects on tumor cells, such as (i) inducing the production of reactive oxygen species (ROS), which contributes to mitochondrial damage; (ii) providing nitric oxide and ROS for the tumor cells, which further react to generate highly toxic reactive nitrogen species (RNS) and cause DNA damage; and (iii) arresting cell cycle at the G0/G1 phase and inducing apoptosis. PSSP@ART-ISMN also demonstrated excellent antitumor activity with good biocompatibility in vivo. Taken together, the results of this work provide a potential delivery strategy for chemotherapy in ovarian cancer.


Assuntos
Nanopartículas , Neoplasias Ovarianas , Feminino , Humanos , Artesunato , Espécies Reativas de Oxigênio , Polímeros , Dinitrato de Isossorbida/metabolismo , Dinitrato de Isossorbida/farmacologia , Dinitrato de Isossorbida/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico
3.
Environ Sci Technol ; 53(24): 14496-14506, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31790222

RESUMO

Microplastics were extracted from freshwater sport fish stomachs containing substantial biomass and identified using optical microscopy, scanning electron microscopy plus energy-dispersive X-ray spectroscopy (SEM/EDS), and Fourier transform infrared (FTIR) micro-spectroscopy with automated spectral mapping. An extraction method is presented that uses a negatively pressurized sieve stack and purified water to preserve plastic surface characteristics and any adsorbed persistent organic pollutants (POPs). This nondestructive extraction method for large predators' stomachs enables multiple trophic-level studies from one fish sampling event and provides other dietary and behavioral data. FTIR-identified microplastics 50-1500 µm, including polyethylene (two with plastic additive POPs), styrene acrylonitrile, polystyrene, and nylon and polyethylene terephthalate fibers 10-50 µm wide. SEM/EDS revealed characteristic surface weathering on the plastic surfaces. The nylon fibers appear to be from human fishing activities, suggesting options for management. Some particles visually identified as potential plastics were revealed by micro-spectroscopy to be mineralized, natural polyamide proteins, or nonplastic shell pieces. A low-cost, reflective sample preparation method with stable particle mounting was developed to enable automated mapping, improved FTIR throughput, and lower detection size limit. This study yielded 37 intact prey items set aside for future analyses.


Assuntos
Peixes , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Água Doce , Microplásticos , Plásticos , Espectroscopia de Infravermelho com Transformada de Fourier , Estômago
4.
Analyst ; 140(17): 6047-53, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26193991

RESUMO

A facile electrochemical sensor for hydroquinone (HQ) and catechol (CC) determination was successfully fabricated by the modification of poly(3-aminophenylboronic acid) (pAPBA) film and multi-walled carbon nanotubes (MWCNTs) on a glassy carbon electrode (pAPBA/MWCNTs/GCE). The prepared sensor was characterized by scanning electron microscope and electrochemical impedance spectroscopy. Under optimal conditions, differential pulse voltammetry was employed to quantify individual HQ and CC within the concentration range of 5.0 × 10(-7)-4.0 × 10(-5) mol L(-1) and 7.0 × 10(-6)-1.0 × 10(-4) mol L(-1), respectively. Based on the covalent binding between the boronic acid groups of pAPBA film and the cis-diol-containing molecule, a novel substitution-sensing strategy was proposed for the highly sensitive determination of CC. With the addition of CC into HQ solution, covalent interaction between CC and APBA occurred and the HQ was displaced by CC, resulting in a decrease of HQ oxidation peak current and the increase of the CC oxidation peak current. The summation of both current changes (Δ|IHQ| + Δ|ICC|) were combined for CC sensitive detection in a concentration range of 4.0 × 10(-8)-1.7 × 10(-5) mol L(-1) with a limit of detection of 4.3 × 10(-9) mol L(-1). The sensor was successfully applied to the determination of CC in spiked water samples.


Assuntos
Catecóis/análise , Técnicas de Química Analítica/métodos , Técnicas Eletroquímicas , Hidroquinonas/análise , Nanotubos de Carbono/química , Polímeros/química , Ácidos Borônicos/química , Eletrodos , Eletrólitos/química , Concentração de Íons de Hidrogênio
5.
Biomater Sci ; 12(2): 288-307, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38189655

RESUMO

Ferroptosis, first suggested in 2012, is a type of non-apoptotic programmed cell death caused by the buildup of lipid peroxidation and marked by an overabundance of oxidized poly unsaturated fatty acids. During the last decade, researchers have uncovered the formation of ferroptosis and created multiple drugs aimed at it, but due to poor selectivity and pharmacokinetics, clinical application has been hindered. In recent years, biomedical discoveries and developments in nanotechnology have spurred the investigation of ferroptosis nanomaterials, providing new opportunities for the ferroptosis driven tumours treatment. Additionally, hydrogels have been widely studied in ferroptosis because of their unique 3D structure and excellent controllability. By using these biomaterials, it is possible to achieve controlled release and targeted delivery of drugs, thus increasing the potency of the drugs and minimizing adverse effects. Therefore, summarizing the biomedical nanomaterials, including hydrogels, used in ferroptosis for cancer therapy is a must. This article provides an overview of ferroptosis, detailing its properties and underlying mechanisms. It also categorizes and reviews the use of various nanomaterials in ferroptosis, along with relevant explanations and illustrations. In addition, we discuss the opportunities and challenges facing the application of nanomaterials in ferroptosis. Finally, the development prospects of this field are prospected. This review is intended to provide a foundation for the development and application of biomedical nanomaterials in ferroptosis.


Assuntos
Ferroptose , Nanoestruturas , Neoplasias , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Hidrogéis , Nanotecnologia , Neoplasias/tratamento farmacológico
6.
J Texture Stud ; 54(1): 54-66, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36520339

RESUMO

Real oral processing is the squeezing and shearing between two soft surfaces. The importance of soft palate surface cannot be ignored while focusing on tongue substitutes. Thus the effects of viscoelasticity, roughness of upper jaw substitutes, and fluid rheological properties on lubrication properties were explored by in vitro oral tribology experiments. Different palate substitutes significantly changed the friction curves of pure water, milk, and yogurt. The boundary friction coefficients of pure water and milk are higher under softer or smooth palate substitutes due to stronger viscoelastic responses of friction pairs. Their boundary friction coefficients are lowest at rigid upper jaw substitutes owing to smaller contact angles and deformation. However, the boundary friction coefficient of yogurt is lower owing to its high viscosity, low loss factor, and large particle size under soft friction pairs. In addition, it is highest at rigid palate friction pair because a smaller contact area reduces the entrainment of yogurt, resulting in poor lubricating performance.


Assuntos
Leite , Língua , Animais , Lubrificação , Reologia , Água
7.
Acta Biomater ; 158: 560-570, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36596434

RESUMO

Platinum-based chemotherapy is a first-line therapeutic regimen against ovarian cancer (OC); however, the therapeutic potential is always reduced by glutamine metabolism. Herein, a valid strategy of inhibiting glutamine metabolism was proposed to cause tumor starvation and chemosensitization. Specifically, reactive oxygen species-responsive liposomes were developed to co-deliver cisplatin (CDDP) and bis-2-(5-phenylacetamido-1,3,4-thiadiazol-2-yl) ethyl sulfide (BPTES) [C@B LPs]. The C@B LPs induced effective tumor cell starvation and significantly sensitized OC cells to CDDP by reducing glutathione generation to prevent CDDP detoxification, suppressing ATP production to avoid CDDP efflux, hindering nucleotide synthesis to aggravate DNA damage induced by CDDP, and blocking mammalian target of rapamycin (mTOR) signaling to promote cell apoptosis. More importantly, C@B LPs remarkably inhibited tumor growth in vivo and reduced the side effects. Taken together, this study provided a successful strategy of synergistic chemosensitization and starvation therapy escalating the rate of therapeutic success in OCs. STATEMENT OF SIGNIFICANCE: This work proposed a valid strategy of inhibiting glutamine metabolism to cause tumor starvation and chemosensitization. Specifically, ROS-responsive liposomes were developed to co-deliver cisplatin CDDP and BPTES [C@B LPs]. The C@B LPs induced effective tumor cell starvation and significantly sensitized OC cells to cisplatin by reducing glutathione generation to prevent cisplatin detoxification, suppressing ATP production to avoid cisplatin efflux, hindering nucleotide synthesis to aggravate DNA damage induced by cisplatin, and blocking mTOR signaling to promote cell apoptosis. More importantly, C@B LPs remarkably inhibited tumor growth in vivo and reduced the side effects. Taken together, this study provided a successful strategy of synergistic chemosensitization and starvation therapy escalating the rate of therapeutic success in OCs.


Assuntos
Antineoplásicos , Glutamina , Lipossomos , Neoplasias Ovarianas , Feminino , Humanos , Trifosfato de Adenosina , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Glutamina/metabolismo , Glutationa , Lipopolissacarídeos/uso terapêutico , Lipossomos/farmacologia , Lipossomos/uso terapêutico , Nucleotídeos/farmacologia , Nucleotídeos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Serina-Treonina Quinases TOR
8.
J Hazard Mater ; 421: 126811, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34388933

RESUMO

There is an urgent requirement to treat cellulose present in papermaking black liquor since it induces severe economic wastes and causes environmental pollution. We characterized cellulase activity at different temperatures and pH to seek thermo-alkali-stable cellulase-producing bacteria, a natural consortium of Serratia sp. AXJ-M and Arthrobacter sp. AXJ-M1 was used to improve the degradation of cellulose. Notably, the enzyme activities and the degradation rate of cellulose were increased by 30%-70% and 30% after co-culture, respectively. In addition, the addition of cosubstrates increased the degradation rate of cellulose beyond 30%. The thermo-alkali-stable endoglucanase (bcsZ) gene was derived from the strain AXJ-M and was cloned and expressed. The purified bcsZ displayed the maximum activity at 70 °C and pH 9. Mn2+, Ca2+, Mg2+ and Tween-20 had beneficial effects on the enzyme activity. Structurally, bcsZ potentially catalyzed the degradation of cellulose. The co-culture with ligninolytic activities significantly decreased target the parameters (cellulose 45% and COD 95%) while using the immobilized fluidized bed reactors (FBRs). Finally, toxicological tests and antioxidant enzyme activities indicated that the co-culture had a detoxifying effect on black liquor. Our study showed that Serratia sp. AXJ-M acts synergistically with Arthrobacter sp. AXJ-M1 may be potentially useful for bioremediation for black liquor.


Assuntos
Arthrobacter , Celulase , Álcalis , Arthrobacter/genética , Celulase/genética , Celulose , Serratia/genética
9.
J Control Release ; 350: 525-537, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36055597

RESUMO

To overcome drug resistance and improve precision theranostics for hepatocellular carcinoma (HCC), a nanoplatform with an "off/on" function for multimodality imaging (near-infrared-II (NIR-II) fluorescence imaging, magnetic resonance imaging (MRI), and photoacoustic imaging) and synergistic therapy (photodynamic therapy and ferroptosis) activated by an acidic pH in the tumor microenvironment is proposed. Although many photosensitizers with photodynamic effects have been reported, very few of them have outstanding photodynamic effect and high stability with response to endogenous stimuli capable of NIR-II imaging. Herein, a new amphiphilic photosensitizer SR780 derived from croconaine dye, was developed with satisfactory photodynamic effects and pH-responsive NIR-II imaging. Interestingly, it was deactivated by coordination with Fe3+ (SR780@Fe) and activated during their release under mild acidic condition. Ferroptosis can generate hydroxyl free radical and lipid peroxide, which aggravate the oxidative stress of tumor cells and mediate their death while depleting glutathione (GSH) to enhance photodynamic effect. In situ pH-activatable theranostic nanoplatform, SR780@Fe-PAE-GP, was thus developed by loading SR780@Fe with pH-responsive polymers, modified by a glypican-3 (GPC-3) receptor-targeting peptide. The synergistic antitumor effects were confirmed both in vitro and in vivo, and the tumor inhibition rate of the SR780@Fe-PAE-GP + L treatment group reached 98%.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , Nanopartículas , Neoplasias , Fotoquimioterapia , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Glutationa , Glipicanas/uso terapêutico , Humanos , Concentração de Íons de Hidrogênio , Peróxidos Lipídicos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/tratamento farmacológico , Nanopartículas/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Polímeros/uso terapêutico , Nanomedicina Teranóstica/métodos , Microambiente Tumoral
10.
Ann Transl Med ; 10(10): 584, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35722381

RESUMO

Background: Human dental pulp stem cells (hDPSCs) exhibit excellent differentiation potential and are capable of differentiating into several different cellular phenotypes, including neurons. Platelet-rich plasma (PRP) contains numerous growth factors that can stimulate stem cell differentiation. In this study, we investigated the potential stimulatory effects of PRP on neurogenic differentiation and anti-apoptosis of hDPSCs in injured spinal cords. Methods: The unipotential differentiation capacity of hDPSCs was analyzed by cell surface antigen identification and cell cycle analysis. A spinal cord injury rat model composed of 40 Sprague-Dawley (SD) rats was used to facilitate an in vivo study. Rats were divided into four groups: a double-treatment group (receiving both neurogenic-induced hDPSCs and PRP), two single-treatment groups (receiving neurogenic-induced hDPSCs or PRP) and a sham group (receiving normal saline). The Basso, Beattie, Bresnahan Locomotor Rating Scale was subsequently used to evaluate the motor function of the spinal cord. Cell viability and differentiation of hDPSCs in the damaged spinal cords were analyzed and apoptosis of neural cells was evaluated using the terminal uridine nucleotide end labeling (TUNEL) assay. Results: Growth pattern, cell surface marker and cell cycle analyses revealed that hDPSCs have a high degree of multi-directional differentiation potential and can be induced into neurons in vitro. In the rat spinal cord injury model, double-treatment with hDPSC/PRP or single treatment with hDPSCs or PRP significantly improved motor function compared with the sham group (P<0.05). Apoptosis of neural cells was observed to be significantly higher in the sham group compared to any of the treatment groups. Double-treatment with hDPSCs and PRP resulted in the lowest apoptotic rate among the groups analyzed. Conclusions: hDPSCs exhibit differentiation potential and are capable of transforming into neural cells both in vitro and in vivo. Significantly increased inhibition of neuronal apoptosis and improved motor function recovery of the spinal cord were observed following double-treatment with hDPSCs and PRP compared with the single-treatment groups.

11.
J Mater Sci Mater Med ; 22(2): 327-37, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21221735

RESUMO

The ethylene vinyl acetate copolymer (EVA)/Poly (lactic acid) (PLA) blend and EVA/Poly (ethylene glycol) (PEG) blend were applied as the drug carrier materials for a bi-layer drug-loaded stent coating film, which consisted of a paclitaxel (PTX)-loaded layer and a drug-free EVA layer. The changes of weight and appearance of the drug-free polymeric blend films with increasing time were examined by X-ray diffraction analysis (XRD), gel permeation chromatography (GPC) tests and scanning electronic microscopy (SEM), and the results showed the degradation of PLA and the leaching of PEG from the films. The effects of PLA, PEG and drug contents on in vitro drug release were investigated, and the results demonstrated that the addition of PLA promoted the drug release while the addition of PEG almost did not. Franz cells diffusion test results indicated that the bi-layer structure successfully endowed the stent coating with the release of drug in a unidirectional fashion. The release profiles of films incorporated PTX and the mechanical performance of the film could be customized by readily adjusting the contents of the blend components. Therefore, the polymeric blends could be useful drug carrier materials for drug-loaded stent coating capable of releasing drug in a highly tunable manner.


Assuntos
Materiais Revestidos Biocompatíveis/química , Ácido Láctico/química , Paclitaxel/administração & dosagem , Polímeros/química , Antineoplásicos Fitogênicos/administração & dosagem , Cromatografia em Gel/métodos , Cromatografia Líquida de Alta Pressão/métodos , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Stents Farmacológicos , Bicamadas Lipídicas/química , Microscopia Eletrônica de Varredura/métodos , Poliésteres , Polietilenoglicóis/química , Estresse Mecânico , Difração de Raios X
12.
Acta Bioeng Biomech ; 23(3): 97-107, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34978311

RESUMO

In order to repair the load-bearing cancellous bone defect of the human lower extremity, the development of a porous scaffold with high porosity, appropriate pore size, low elastic modulus and high fatigue strength has been faced with great challenges. In this study, the Ti6Al4V coaxial scaffolds with five types of beam angles and three types of pore sizes were designed using CAD and fabricated with the use of SLM. The porous characteristics and mechanical properties of scaffolds were investigated systematically. The results show that the porosity of the coaxial scaffolds is 63-69%, and the pore size is 480-700 µm. Meanwihle, the elastic modulus and compressive strength of the coaxial scaffolds were 1.08-1.85 GPa, 40-88 MPa, respectively. Moreover, the fatigue strength of the coaxial scaffolds with 500-40°, 600-40°, 700-40° were 1387, 1110 and 420 MPa, respectively. The pore size and porosity of the coaxial scaffolds in our study satisfied the size requirements for bone cells growth. Meanwhile, the low elastic modulus and high fatigue strength of the scaffolds also met the bio-mechanical bearing requirements of cancellous bone implants. Our study provided a reference for the design of biomimetic cancellous bone implants with good dynamic load-bearing mechanical properties.


Assuntos
Biônica , Osso Esponjoso , Ligas , Humanos , Porosidade , Titânio , Suporte de Carga
13.
Zhonghua Wai Ke Za Zhi ; 48(10): 784-7, 2010 May 15.
Artigo em Zh | MEDLINE | ID: mdl-20646499

RESUMO

OBJECTIVE: To evaluate the anti degenerative effect of pectin/polyvinyl alcohol composite (CoPP) hydrogel as artificial nucleus material in an animal model. METHODS: Thirty-six New Zealand white rabbits were used to build animal models, the L4₋5 intervertebral discs were pierced with a Gauge#16 needle and polyvinyl alcohol (PVA) or CoPP implants were inserted into the holes. For comparative purposes, L3₋4 discs underwent sham treatment or control treatment in which the disc was pierced but no implant was inserted. All the discs were divided into four groups as follows: sham disc group, pierced disc group, PVA disc group and CoPP disc group. The discs were analyzed radiologically and histologically for degenerative changes at 1, 3 or 6 months after surgery. RESULTS: None of the animals died from operative complications, such as paraplegia or infection before being killed. Macroscopically, none of the implants showed any signs of displacement at the time of harvest. The radiological analysis revealed that significantly less disc height loss was found with the PVA and CoPP replacement treatment than with the pierced treatment (P < 0.05). Changes in disc height after the replacement treatment were not significantly different from that after the sham treatment (P > 0.05). Histological degeneration of the replaced discs was delayed in comparison with that of the pierced discs (P < 0.05), but progressed with time, and PVA replacement showed faster disc degeneration than CoPP replacement. CONCLUSIONS: Degeneration of the anulus fibrosus after the CoPP prosthetic nucleus replacement treatment is delayed by preserving disc height and occupying the space of the nucleus pulposus, and it has great potential clinical application value.


Assuntos
Implantes Experimentais , Disco Intervertebral/cirurgia , Pectinas/uso terapêutico , Álcool de Polivinil/uso terapêutico , Animais , Feminino , Disco Intervertebral/patologia , Vértebras Lombares/cirurgia , Masculino , Modelos Animais , Coelhos
14.
Biomed Res Int ; 2020: 1353516, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33029488

RESUMO

Charcot-Marie-Tooth Disease (CMT) is the most common clinical genetic disease of the peripheral nervous system. Although many studies have focused on elucidating the pathogenesis of CMT, few focuses on achieving a systematic analysis of biology to decode the underlying pathological molecular mechanisms and the mechanism of its disease remains to be elucidated. So our study may provide further useful insights into the molecular mechanisms of CMT based on a systematic bioinformatics analysis. In the current study, by reviewing the literatures deposited in PUBMED, we identified 100 genes genetically related to CMT. Then, the functional features of the CMT-related genes were examined by R software and KOBAS, and the selected biological process crosstalk was visualized with the software Cytoscape. Moreover, CMT specific molecular network analysis was conducted by the Molecular Complex Detection (MCODE) Algorithm. The biological function enrichment analysis suggested that myelin sheath, axon, peripheral nervous system, mitochondrial function, various metabolic processes, and autophagy played important roles in CMT development. Aminoacyl-tRNA biosynthesis, metabolic pathways, and vasopressin-regulated water reabsorption were significantly enriched in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway network, suggesting that these pathways may play key roles in CMT occurrence and development. According to the crosstalk, the biological processes could be roughly divided into a correlative module and two separate modules. MCODE clusters showed that in top 3 clusters, 13 of CMT-related genes were included in the network and 30 candidate genes were discovered which might be potentially related to CMT. The study may help to update the new understanding of the pathogenesis of CMT and expand the potential genes of CMT for further exploration.


Assuntos
Doença de Charcot-Marie-Tooth/genética , Biologia Computacional/métodos , Mapas de Interação de Proteínas/genética , Algoritmos , Estudos de Associação Genética , Humanos , Software
15.
Anal Methods ; 12(45): 5450-5457, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33135024

RESUMO

A new protocol for the extraction of microplastic is proposed and demonstrated which combines dissection, ultrasonication, and filtration with chemical dissolution in order to estimate microplastic contamination in fish or other samples with significant biomass. This protocol enables initial characterization of the sample through dissection followed by chemical dissolution to isolate polymer debris while minimizing analytical uncertainties and maintaining microplastic particle integrity. The extraction method begins with dissection and inspection of the stomach contents, followed by pulsed ultrasonic extraction to remove the majority of biomass and surface contaminants. Subsequent chemical dissolution of the extracted contents using KOH and HCl removes any remaining biomass and inorganic interferences. Incorporating chemical dissolution post-extraction minimizes the overall biomass subjected to dissolution, thereby enabling faster processing and subsequently a cleaner sample compared to methods involving digestion of the entire organism. Furthermore, the chemical dissolution step enables direct filter analysis for microplastics, thereby minimizing the potential loss of microplastic particles associated with manual particle transfer. Hence, the microplastic extraction method presented here is suitable for the extraction and identification of small (>20 µm) and potentially brittle microplastic.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Plásticos , Solubilidade , Poluentes Químicos da Água/análise
16.
Environ Pollut ; 267: 115388, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33254703

RESUMO

In the present work, acute impact of heavy metals on activated sludge was investigated, specifically the release of biopolymers and nitrogenous soluble microbiological products (N-SMP) that significantly impact tertiary effluent quality. Based on the previously reported studies, Hg2+ and Ag+ were selected as representative "non-essential" heavy metals, while Cu2+ was selected as the "essential" heavy metal. Stress tests show that under the present experimental conditions, adding a higher concentration of heavy metals to the activated sludge increases the concentration of biopolymers and SMP in the supernatant; N-SMP increased more significantly than carbonaceous products, implying a greater risk of formation of toxic nitrogenous disinfection by-products or membrane fouling in relevant tertiary treatment processes. The severity of the release of SMP into the supernatant depended on the heavy metal, with an order of Hg2+ > Ag+ > Cu2+ ("non-essential" > "essential") under identical molar concentrations. The mass balance of typical organics (e.g., biopolymers) in SMP and extracellular polymeric substances (EPS) in activated sludge was analyzed, and a negative correlation between the organics in the SMP and tightly bound EPS was observed, implying that a significant fraction of the SMP could be quickly released from the tightly bound EPS under heavy metal shock conditions and could be related to cell response or damage.


Assuntos
Mercúrio , Esgotos , Biopolímeros , Reatores Biológicos , Nitrogênio , Prata , Águas Residuárias
17.
Environ Pollut ; 233: 1113-1124, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29037491

RESUMO

Pacific Ocean trawl samples, stomach contents of laboratory-raised fish as well as fish from the subtropical gyres were analyzed by Raman micro-spectroscopy (RMS) to identify polymer residues and any detectable persistent organic pollutants (POP). The goal was to access specific molecular information at the individual particle level in order to identify polymer debris in the natural environment. The identification process was aided by a laboratory generated automated fluorescence removal algorithm. Pacific Ocean trawl samples of plastic debris associated with fish collection sites were analyzed to determine the types of polymers commonly present. Subsequently, stomach contents of fish from these locations were analyzed for ingested polymer debris. Extraction of polymer debris from fish stomach using KOH versus ultrapure water were evaluated to determine the optimal method of extraction. Pulsed ultrasonic extraction in ultrapure water was determined to be the method of choice for extraction with minimal chemical intrusion. The Pacific Ocean trawl samples yielded primarily polyethylene (PE) and polypropylene (PP) particles >1 mm, PE being the most prevalent type. Additional microplastic residues (1 mm - 10 µm) extracted by filtration, included a polystyrene (PS) particle in addition to PE and PP. Flame retardant, deca-BDE was tentatively identified on some of the PP trawl particles. Polymer residues were also extracted from the stomachs of Atlantic and Pacific Ocean fish. Two types of polymer related debris were identified in the Atlantic Ocean fish: (1) polymer fragments and (2) fragments with combined polymer and fatty acid signatures. In terms of polymer fragments, only PE and PP were detected in the fish stomachs from both locations. A variety of particles were extracted from oceanic fish as potential plastic pieces based on optical examination. However, subsequent RMS examination identified them as various non-plastic fragments, highlighting the importance of chemical analysis in distinguishing between polymer and non-polymer residues.


Assuntos
Monitoramento Ambiental , Conteúdo Gastrointestinal/química , Polímeros/análise , Resíduos/análise , Poluentes Químicos da Água/análise , Animais , Oceano Atlântico , Peixes , Oceanos e Mares , Oceano Pacífico , Plásticos/análise , Polietileno/análise , Poliestirenos/análise , Água do Mar/química , Análise Espectral Raman , Estômago/química
18.
J Mech Behav Biomed Mater ; 82: 87-94, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29574279

RESUMO

Ultra-low-wear polyethylene (ULWPE) is a new type polyethylene made by experts who are from China petrochemical research institute, which is easy to process and implant. Preliminary test showed it was more resistant to wear than that of Ultra-high-molecular weight polyethylene (UHMWPE). The purpose of the research is to study biocompatibility, bio-tribological properties and debris characterization of ULWPE. Cytotoxicity test, hemolysis test, acute/chronic toxicity and muscular implantation test were conducted according to national standard GB/T-16886/ISO-10993 for evaluation requirements of medical surgical implants. We obtained that this novel material had good biocompatibility and biological safety. The wear performance of ULWPE and UHMWPE was evaluated in a pin-on-disc (POD) wear tester within two million cycles and a knee wear simulator within six million cycles. We found that the ULWPE was higher abrasion resistance than the UHMWPE, the wear rate of ULWPE by POD test and knee wear simulator was 0.4 mg/106cycles and (16.9 ±â€¯1.8)mg/106cycles respectively, while that of UHMWPE was 1.8 mg/106cycles and (24.6 ±â€¯2.4)mg/106cycles. The morphology of wear debris is also an important factor to evaluate artificial joint materials, this study showed that the ULWPE wear debris gotten from the simulator had various different shapes, including spherical, block, tear, etc. The morphology of worn surface and wear debris analysis showed that wear mechanisms of ULWPE were adhesion wear, abrasive wear and fatigue wear and other wear forms, which were consistent with that of UHMWPE. Thus we conclude that ULWPE is expected to be a lifetime implantation of artificial joint.


Assuntos
Prótese Articular , Teste de Materiais , Polietilenos/toxicidade , Linhagem Celular , Hemólise/efeitos dos fármacos , Fenômenos Mecânicos , Polietilenos/química , Propriedades de Superfície
19.
Chem Commun (Camb) ; (41): 4245-7, 2007 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-18217594

RESUMO

Threading molecular square "beads" on a twofold interpenetrated diamondoid skeleton gives a new type of 3D metal-organic polyrotaxane framework with large channels, in which nanosized Keggin anions as guests are encapsulated for the first time.


Assuntos
Compostos Organometálicos/síntese química , Polímeros/química , Rotaxanos/química , Compostos de Tungstênio/química , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/química
20.
Int J Pharm ; 333(1-2): 95-102, 2007 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17110064

RESUMO

The drug percolation thresholds of 5-fluorouracil-loaded ethylene-vinyl acetate stent coatings were estimated to characterize their drug release behavior and mechanical properties. The stent coatings were prepared using 5-fluorouracil (5-FU) as antitumor drug and ethylene-vinyl acetate (EVA) as matrix forming material in different ratios. In vitro release assays were carried out exposing only one side of coating to pH 6.5 PBS. Based on the release profiles, the drug percolation thresholds were estimated as 0.21 of total porosity (corresponding to ca. 32%, w/w of the drug), which is in approximately agreement with the atomic force microscopy (AFM) result. Based on the coating tensible break strength and tear break strength data, the mechanical percolation thresholds of drug were obtained as 39.7+/-0.3 and 37.5+/-1.4% (w/w) of drug content, respectively.


Assuntos
Antimetabólitos Antineoplásicos/química , Materiais Revestidos Biocompatíveis , Portadores de Fármacos , Fluoruracila/química , Polivinil/química , Stents , Química Farmacêutica , Difusão , Concentração de Íons de Hidrogênio , Teste de Materiais , Microscopia de Força Atômica , Modelos Químicos , Modelos Estatísticos , Porosidade , Solubilidade , Estresse Mecânico , Resistência à Tração , Fatores de Tempo
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