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Domestic organic waste resources have increased over the past decade and treatment of this waste via co-digested biogasification facilities is increasing annually. However, inspection standards for such facilities are not well-established. Herein, we aimed to derive calculation formulas and factors related to organic matter decomposition efficiency and methane production rate in accordance with waste treatment facility inspection standards. We also aimed to determine the optimum waste mixing ratio. Sample (field) surveys of 18 treatment facilities and complete enumeration of 110 facilities were conducted. Calculation formulas and factors were derived using the survey data and biochemical methane potential (BMP) test. The calculated coefficients derived through the BMP test were 0.512 m3 CH4/kgVSin for food waste, 0.601 m3 CH4/kgVSin for livestock manure, and 0.382 m3 CH4/kgVSin for sewage sludge. The final derived calculation factors were 65.0% for food waste, 36.0% for livestock manure, and 20.0% for sewage sludge for organic matter decomposition efficiency, and 0.380 m3 CH4/kgVSin for food waste, 0.27 m3 CH4/kgVSin for livestock manure, and 0.140 m3 CH4/kgVSin for sewage sludge for methane production rates. The derived effective capacity calculation factors can be utilized in future waste treatment facility inspection methods by aiding in the establishment of appropriate inspection standards for co-digested biogasification facilities other than single food waste treatment facilities. In addition, the optimum mixing ratio can be used as design data for co-digested biogasification facilities.
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Eliminación de Residuos , Aguas del Alcantarillado , Aguas del Alcantarillado/química , Anaerobiosis , Alimentos , Estiércol/análisis , Reactores Biológicos , Alimento Perdido y Desperdiciado , Metano/análisis , Digestión , República de CoreaRESUMEN
A facile oxygen (O2) atmospheric plasma treatment is applied to a polyvinyl alcohol (PVA) matrix to enhance its wettability and hydrophilicity. The optimal plasma treatment conditions are determined by varying the applied plasma power and plasma treatment time. A PVA matrix treated with a plasma power of 120 W for 5 s shows the most hydrophilicity owing to successful formation of carbonyl (-CO, >C=O) functional groups without any structural degradation. The plasma-treated PVA matrix is used as the gel-polymer electrolyte of a solid-state supercapacitor (SSC) by immersing solid matrix into various liquid electrolytes, such as sodium sulfate (Na2SO4), sulfuric acid (H2SO4), and potassium hydroxide (KOH). Compared with the pristine PVA-based device, PVA-120W5/Na2SO4-, PVA-120W5/H2SO4-, and PVA-120W5/KOH-based SSCs show 2.03, 2.05, and 2.14 times higher specific capacitances, respectively. The plasma-treated PVA matrix shows increased specific capacitance owing to the increased wettability, which in turn increases the ion transportation and reduces the electrical resistance. This study successfully demonstrates that the electrochemical performance of a SSC can be readily enhanced through plasma treatment for a short time (≤5 s).
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In this study, a flexible all-solid-state asymmetric supercapacitor (FASC) device has been successfully fabricated via full recycling of heated tobacco waste (HTW). Tobacco leaves and cellulose acetate tubes have been successfully carbonized (HTW-C) and mixed with metal oxides (MnO2 and Fe3O4) to obtain highly active materials for supercapacitors. Moreover, poly(lactic acid) (PLA) filters have been successfully dissolved in an organic solvent and mixed with the as-prepared active materials using a simple paste mixing method. In addition, flexible MnO2- and Fe3O4-mixed HTW-C/PLA electrodes (C-MnO2/PLA and C-Fe3O4/PLA) have been successfully fabricated using the drop-casting method. The as-synthesized flexible C-MnO2/PLA and C-Fe3O4/PLA electrodes have exhibited excellent electrical conductivity of 378 and 660 µS cm-1, and high specific capacitance of 34.8 and 47.9 mF cm-2 at 1 mA cm-2, respectively. A practical FASC device (C-MnO2/PLA//C-Fe3O4/PLA) has been assembled by employing the C-MnO2/PLA as the positive electrode and C-Fe3O4/PLA as the negative electrode. The as-prepared FASC device showed a remarkable capacitance of 5.80 mF cm-2 at 1 mA cm-2. Additionally, the FASC device manifests stable electrochemical performance under harsh bending conditions, verifying the superb flexibility and sustainability of the device. To the best of our knowledge, this is the first study to report complete recycling of heated tobacco waste to prepare the practical FASC devices. With excellent electrochemical performance, the experiments described in this study successfully demonstrate the possibility of recycling new types of biomass in the future.
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High-pressure anaerobic digestion (HPAD) is a promising technology for producing biogas enriched with high methane content in a single-step process. To enhance HPAD performance, a comprehensive understanding of microbial community dynamics and their interactions is essential. For this, mesophilic batch high-pressurized anaerobic reactors were operated under 3 bars (H3) and 6 bars (H6). The experimental results showed that the effect of high-pressure (up to 6 bar) on acidification was negligible while methanogenesis was significantly delayed. Microbial analysis showed the predominance of Defluviitoga affiliated with the phylum Thermotogae and the reduction of Thiopseudomonas under high-pressure conditions. In addition, the microbial cluster pattern in H3 and H6 was significantly different compared to the CR, indicating a clear shift in microbial community structure. Moreover, Methanobacterium, Methanomicrobiaceae, Alkaliphilus, and Petrimonas were strongly correlated in network analysis, and they could be identified as keystone microbes in the HPAD reactor.
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Reactores Biológicos , Metano , Anaerobiosis , Reactores Biológicos/microbiología , Biocombustibles , Interacciones MicrobianasRESUMEN
Light detection and ranging (LiDAR) sensors utilize a near-infrared (NIR) laser with a wavelength of 905 nm. However, LiDAR sensors have weakness in detecting black or dark-tone materials with light-absorbing properties. In this study, SiO2/black TiO2 core/shell nanoparticles (SBT CSNs) were designed as LiDAR-detectable black materials. The SBT CSNs, with sizes of 140, 170, and 200 nm, were fabricated by a series of Stöber, TTIP sol-gel, and modified NaBH4 reduction methods. These SBT CSNs are detectable by a LiDAR sensor and, owing to their core/shell structure with intrapores on the shell (ca. 2−6 nm), they can effectively function as both color and NIR-reflective materials. Moreover, the LiDAR-detectable SBT CSNs exhibited high NIR reflectance (28.2 R%) in a monolayer system and true blackness (L* < 20), along with ecofriendliness and hydrophilicity, making them highly suitable for use in autonomous vehicles.
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Herein, the electrorheological (ER) performances of ER fluids were correlated with their colors to allow for the visual selection of the appropriate fluid for a specific application using naked eyes. A series of TiO2-coated synthetic mica materials colored white, yellow, red, violet, blue, and green (referred to as color mica/TiO2 materials) were fabricated via a facile sol-gel method. The colors were controlled by varying the thickness of the TiO2 coating layer, as the coatings with different thicknesses exhibited different light interference effects. The synthesized color mica/TiO2 materials were mixed with silicone oil to prepare colored ER fluids. The ER performances of the fluids decreased with increasing thickness of the TiO2 layer in the order of white, yellow, red, violet, blue, and green materials. The ER performance of differently colored ER fluids was also affected by the electrical conductivity, dispersion stability, and concentrations of Na+ and Ca2+ ions. This pioneering study may provide a practical strategy for developing new ER fluid systems in future.
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Cardiovascular diseases, such as stroke, are the most common causes of death in developed countries. Ischemic stroke accounts for 85% of the total cases and is caused by abnormal thrombus formation in the vessels, causing deficient blood and oxygen supply to the brain. Prophylactic treatments include the prevention of thrombus formation, of which the most used is acetylsalicylic acid (ASA); however, it is associated with a high incidence of side effects. Angelica gigas Nakai (AG) is a natural herb used to improve blood circulation via anti-platelet aggregation, one of the key processes involved in thrombus formation. We examined the antithrombotic effects of AGE 232, the ethanol extract of A. gigas Nakai. AGE 232 showed a significant reduction in death or paralysis in mice caused by collagen/epinephrine-induced thromboembolism in a dose-dependent manner and inhibition of collagen-induced human platelet aggregation in a concentration-dependent manner. Additionally, AGE 232-treated mice did not show severe bleeding in the gut compared to ASA-treated mice. AGE 232 resulted in a decrease in the number of neutrophils attached to the human umbilical vein endothelial cells (HUVECs) and lower inhibition of COX-1 in response to bleeding and damage to blood vessels, a major side effect of ASA. Therefore, AGE 232 can prevent thrombus formation and stroke.
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Thrombosis causes poor blood circulation, which may lead to several cardiovascular disorders. Antiplatelet aggregation and antihyperlipidemia are the key processes that improve blood circulation. The antiplatelet aggregation and antihyperlipidemic effects of ACG-1, a mixture of Angelica gigas, Cynanchum wilfordii, and Ginkgo biloba extracts, were investigated in this study. The antiplatelet aggregation activity of ACG-1 was determined by studying its effects on collagen-induced platelet aggregation in human platelet-rich plasma (PRP). In addition, the effects of ACG-1 were investigated in a thromboembolism mouse model. The high-fat diet (HFD)-fed mouse model was used to investigate the antihyperlipidemic effects of ACG-1 and western blotting assay was performed to elucidate its mechanism of action. It was observed that ACG-1 significantly inhibited platelet aggregation in human PRP. Furthermore, ACG-1 showed protective effects in a thromboembolism mouse model induced by administering a mixed collagen and epinephrine intravenous injection. Oral administration of ACG-1 also significantly ameliorated blood lipid profiles in the HFD-fed mouse model. In conclusion, ACG-1 should be considered a powerful functional food to improve blood circulation.
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Angelica , Circulación Sanguínea , Cynanchum , Ginkgo biloba , Extractos Vegetales , Agregación Plaquetaria , Angelica/química , Animales , Circulación Sanguínea/efectos de los fármacos , Cynanchum/química , Modelos Animales de Enfermedad , Ginkgo biloba/química , Humanos , Ratones , Extractos Vegetales/farmacología , Agregación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/farmacología , Tromboembolia/tratamiento farmacológicoRESUMEN
One application of nanotechnology in medicine that is presently being developed involves a drug delivery system (DDS) employing nanoparticles to deliver drugs to diseased sites in the body avoiding damage of healthy tissue. Recently, the mild hyperthermia-triggered drug delivery combined with anticancer agent-loaded thermosensitive liposomes was widely investigated. In this study, thermosensitive liposomes (TSLs), composed of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol)-2000] (DSPE-PEG), cholesterol, and a fatty acid conjugated elastin-like polypeptide (ELP), were developed and optimized for triggered drug release, controlled by external heat stimuli. We introduced modified ELP, tunable for various biomedical purposes, to our thermosensitive liposome (e-TSL) to convey a high thermoresponsive property. We modulated thermosensitivity and stability by varying the ratios of e-TSL components, such as phospholipid, ELP, and cholesterol. Experimental data obtained in this study corresponded to results from a simulation study that demonstrated, through the calculation of the lateral diffusion coefficient, increased permeation of the lipid bilayer with higher ELP concentrations, and decreased permeation in the presence of cholesterol. Finally, we identified effective drug accumulation in tumor tissues and antitumor efficacy with our optimized e-TSL, while adjusting lag-times for systemic accumulation.
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Colesterol/química , Liposomas/química , Péptidos/química , Fosfolípidos/química , Animales , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/farmacocinética , Química Farmacéutica , Modelos Animales de Enfermedad , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacocinética , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Humanos , Membrana Dobles de Lípidos/química , Masculino , Ratones , Simulación del Acoplamiento Molecular , Nanopartículas/química , Nanopartículas/ultraestructura , Tamaño de la Partícula , Termodinámica , Temperatura de Transición , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Castleman's disease (CD) is a rare lymphoproliferative disorder that can involve single or multiple lymph nodes in the body. Especially, the localized form of CD is known to be well-controlled by using a surgical resection. On occasion, the surgeon may confront an abdominal and retroperitoneal mass of unknown origin. Thus, we present this case in which we treated a 16-year-old female patient for CD and investigated how to evaluate and manage the situation from the standpoint of CD. Also, we give a review of the pathology, clinical manifestation, diagnosis, and treatment of CD.
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One of the most effective methods to treat cancer is the specific delivery of anticancer drugs to the target site. To achieve this goal, we designed an anticancer drug with mild hyperthermia-mediated triggering and tumor-specific delivery. To enhance the thermosensitive drug release, we incorporated elastin-like polypeptide (ELP), which is known to be a thermally responsive phase transition peptide into the dipalmitoylphosphatidylcholine (DPPC)-based liposome surface. Additionally, cyclic arginine-glycine-aspartic acid (cRGD) binds to αvß3 integrin, which is overexpressed in angiogenic vasculature and tumor cells, was introduced on the liposome. ELP-modified liposomes with the cRGD targeting moiety were prepared using a lipid film hydration method, and doxorubicin (DOX) was loaded into the liposome by the ammonium sulfate-gradient method. The cRGD-targeted and ELP-modified DOX-encapsulated liposomes (RELs) formed spherical vesicles with a mean diameter of 181 nm. The RELs showed 75% and 83% DOX release at 42°C and 45°C, respectively. The stability of RELs was maintained up to 12h without the loss of their thermosensitive function for drug release. Flow cytometry results showed that the cellular uptake of DOX in RELs into αvß3 integrin-overexpressing U87MG and HUVEC cells was 8-fold and 10-fold higher, respectively, than that of non-targeting liposomes. Confocal microscopy revealed that REL released DOX only under the mild hyperthermia condition at 42°C by showing the localization of DOX in nuclei and the liposomes in the cytosol. The cell cytotoxicity results demonstrated that REL can efficiently kill U87MG cells through cRGD targeting and thermal triggering. The in vivo tumoral accumulation measurement showed that the tumor-targeting effect of RELs was 5-fold higher than that of non-targeting liposomes. This stable, target-specific, and thermosensitive liposome shows promise to enhance therapeutic efficacy if it is applied along with a relevant external heat-generating medical system.
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Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Péptidos Cíclicos/administración & dosificación , Péptidos Cíclicos/química , Temperatura , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Doxorrubicina/química , Doxorrubicina/farmacología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Liposomas , Estructura Molecular , Relación Estructura-Actividad , Especificidad por SustratoRESUMEN
BACKGROUND AND AIM: Although transnasal endoscopy (TNE) is generally a comfortable and safe procedure, it has some disadvantages, such as complicated preprocessing and occasional repulsion reaction during catheterization. In an attempt to simplify the preprocessing method, the efficacy of a catheter-free method in which a catheter is not inserted into the nasal cavity was assessed. METHODS: The present study was a prospective, open-label, single-center, randomized controlled study with parallel assignment allocation 1:1. Between March 2009 and August 2009, a total of 93 TNE-naïve patients were enrolled and randomized. Patients were prospectively randomized into two groups (catheter-free vs catheter-insertion method). Patients who prepared according to the catheter-free method and who were unsuccessful underwent the catheter-insertion method. Clinical characteristics, success rate, complications, vital signs, acceptability, and tolerability were assessed and compared. RESULTS: Success rates of the catheter-free and catheter-insertion methods were 88% (n=44) and 88% (n=38) (P>0.05), respectively. Causes of failure in the catheter-free method included severe rhinalgia (n=1, 2%) and narrowing of the nasal cavity (n=5, 10%). Causes of failure in the catheter-insertion method included narrowing of the nasal cavity (n=5, 11%). Six patients whose TNE failed with the catheter-free method also experienced failed TNE with the catheter-insertion method. There were no statistical differences in vital signs, acceptability, and tolerability. CONCLUSION: The catheter-free method is sufficient for preparation for TNE. The success rate of TNE depends more on the structure of the nasal cavity than the preprocessing method.
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Catéteres , Endoscopios Gastrointestinales , Endoscopía Gastrointestinal/métodos , Anciano , Anestesia Local/métodos , Endoscopía Gastrointestinal/instrumentación , Femenino , Humanos , Lidocaína/administración & dosificación , Masculino , Persona de Mediana Edad , Cavidad Nasal , Dimensión del Dolor , Satisfacción del Paciente , Estudios Prospectivos , República de CoreaRESUMEN
We developed a novel temperature-sensitive liposome, STL composed of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol)-2000] (DSPE-PEG-2000), cholesterol, and a fatty acid conjugated elastin-like polypeptide (ELP). The STL had a unilamellar spherical shape with a mean diameter of 160 nm. Doxorubicin (DOX) was encapsulated by the STL using an ammonium sulfate gradient method with a lipid to drug ratio of 1:0.2 (w/w), resulting in 95% loading efficiency. The STL exhibited better stability than conventional low temperature sensitive liposome (LTSL-lysolipid-based temperature sensitive liposomes; DPPC:MSPC:DSPE-PEG-2000=90:10:4) at 37 °C in the presence of serum; there was rapid release of doxorubicin in the range of 39-42 °C (≥95% release at 42 °C within 10s). A confocal microscope revealed that DOX encapsulated in STL (STL-DOX) was taken up much better by cell nuclei at 42 °C than at 37 °C. The difference in cell viability between 37 and 42 °C was 63% relative to STL-DOX and 18% for LTSL-DOX. The pharmacokinetics (PK) and antitumor effect of STL-DOX combined with high-intensity focused ultrasound (HIFU) were studied, and compared with LTSL. An in vivo study demonstrated that STL-DOX is highly stable, with a long circulating property (half life=2.03±0.77 h) in HIFU-untreated mice, and resulted in significant tumor regression for 2 days after intravenous injection of STL-DOX at 5 mg DOX/kg in combination with HIFU. These results are better than conventional LTSL, for which the blood circulation time is short (0.92±0.17 h) and inhibition of tumor growth is weak. These results indicate that the properties of stability at 37 °C and burst release at 42 °C of STL-DOX act synergistically against tumors.
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Antibióticos Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Ultrasonido Enfocado de Alta Intensidad de Ablación , Neoplasias/terapia , Animales , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Química Farmacéutica , Terapia Combinada , Doxorrubicina/química , Doxorrubicina/farmacocinética , Células HeLa , Humanos , Lípidos/química , Liposomas , Masculino , Ratones , Ratones Endogámicos BALB C , Neoplasias/patología , Temperatura , Carga Tumoral/efectos de los fármacosRESUMEN
PURPOSE: Ostomy takedown is often considered a simple procedure without intention; however, it is associated with significant morbidity. This study is designed to evaluate factors predicting postoperative complications in the ostomy takedown in view of metabolism and nutrition. METHODS: A retrospective, institutional review-board-approved study was performed to identify all patients undergoing takedown of an ostomy from 2004 to 2010. RESULTS: Of all patients (150), 48 patients (32%; male, 31; female, 17) had complications. Takedown of an end-type ostomy showed a high complication rate; complications occurred in 55.9% of end-type ostomies and 15.7% of loop ostomies (P < 0.001). Severe adhesion was also related to a high rate of overall complication (41.3%) (P = 0.024). In preoperative work-up, ostomy type was not significantly associated with malnutrition status. However, postoperatively severe malnutrition level (albumin <2.8 mg/dL) was statistically significant in increasing the risk of complications (72.7%, P = 0.015). In particular, a significant postoperative decrease in albumin (>1.3 mg/dL) was associated with postoperative complications, particularly surgical site infection (SSI). Marked weight loss such as body mass index downgrading may be associated with the development of complications. CONCLUSION: A temporary ostomy may not essentially result in severe malnutrition. However, a postoperative significant decrease in the albumin concentration is an independent risk factor for the development of SSI and complications.
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pH-Responsive polymeric micelles have been investigated as drug carriers for chemotherapy. Ligand-mediated polymeric micelles, which can penetrate the target tumors due to their high binding affinity to a specific receptor on the surface of tumors, were developed to achieve targeted drug delivery. In this study, biotin-conjugated methoxypoly(ethylene glycol)-grafted-poly(ß-amino ester) was prepared for active and pH-sensitive tumor targeting. These polymers were modified by cholesteryl chloroformate to improve the hydrophobicity of the micelle core. The structure of the biotin-conjugated polymer was confirmed by (1)H NMR spectroscopy, and the existence of biotin at the surface of the polymeric micelles was evaluated by an 4'-hydroxyazobenzene-2-carboxylic acid/avidin (HABA/avidin) binding assay at different pHs. The micelle properties were determined by dynamic light scattering and the result showed that the mean size of the polymeric micelles was approximately 20 nm. For cancer therapy, doxorubicin (DOX) was loaded into the polymeric micelles with a high loading efficiency. From the in vitro cellular uptake results, the biotin-conjugated polymeric micelles can effectively release doxorubicin at acidic tumor cells compared to the micelles without biotin. Overall, biotin-conjugated pH-responsive polymeric micelles have great potential to be used as drug carriers.
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Biotina/química , Portadores de Fármacos/química , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/metabolismo , Avidina , Compuestos Azo , Línea Celular , Colesterol/química , Doxorrubicina/administración & dosificación , Doxorrubicina/metabolismo , Sistemas de Liberación de Medicamentos , Humanos , Concentración de Iones de Hidrógeno , Luz , Micelas , Vehículos Farmacéuticos , Polietilenglicoles/química , Polímeros/química , Dispersión de Radiación , Espectrofotometría UltravioletaRESUMEN
In this study, some possible biomedical applications of a pH-sensitive and amphiphilic copolymer as a pH sensor and protein delivery system are reported. PAE-g-PEG was used as a pH-sensitive polymer that can exhibit a sharp pH-dependent transition. Various fluorescent dyes including pyrene and RITC can be used to label the pH-sensitive polymer PAE-g-PEG, which was evaluated for protein encapsulation. pH-sensing was possible by observing excimer formation of the labeled pyrene via pH-dependent expansion of the polymeric chain. Also, it was confirmed that FITC-BSA could be entrapped in RITC-labeled pH-sensitive micelles of PAE-g-PEG by FRET. As a result, PAE-g-PEG can be a pH sensor and carrier for protein delivery.
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Fluoresceína-5-Isotiocianato/análogos & derivados , Polietilenglicoles/química , Polímeros/química , Albúmina Sérica Bovina/química , Animales , Cationes/química , Bovinos , Fluoresceína-5-Isotiocianato/química , Concentración de Iones de Hidrógeno , Transporte de ProteínasRESUMEN
We report protoporphyrin IX (PpIX) encapsulated pH-responsive micelles for cancer treatment. This system showed pH-responsive micellization/demicellization transition at tumoral acidic pH and enabled in vivo tumor diagnosis and therapy simultaneously.
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Micelas , Neoplasias/diagnóstico , Neoplasias/tratamiento farmacológico , Fotoquimioterapia , Fármacos Fotosensibilizantes/administración & dosificación , Polímeros/química , Protoporfirinas/administración & dosificación , Animales , Portadores de Fármacos/química , Concentración de Iones de Hidrógeno , Ratones , Microscopía FluorescenteRESUMEN
Novel biodegradable and pH-sensitive polymersomes prepared from poly(ethylene glycol) and poly(d,l-lactide) grafted poly(beta-amino ester) exhibit pH dependent permeability on hydrophilic solutes of which permeability is determined by the packing state of poly(d,l-lactide) membrane followed by ionization of poly(beta-amino ester) inducing loosely packed membrane formation from well-ordered packing.