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1.
Small ; 20(26): e2311802, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38258398

RESUMEN

Conductive polymers are recognized as ideal candidates for the development of noninvasive and wearable sensors for real-time monitoring of potassium ions (K+) in sweat to ensure the health of life. However, the low ion-to-electron transduction efficiency and limited active surface area hamper the development of high-performance sensors for low-concentration K+ detection in the sweat. Herein, a wearable K+ sensor is developed by tailoring the nanostructure of polypyrrole (PPy), serving as an ion-to-electron transduction layer, for accurately and stably tracing the K+ fluctuation in human sweat. The PPy nanostructures can be tailored from nanospheres to nanofibers by controlling the supramolecular assembly process during PPy polymerization. Resultantly, the ion-to-electron transduction efficiency (17-fold increase in conductivity) and active surface area (1.3-fold enhancement) are significantly enhanced, accompanied by minimized water layer formation. The optimal PPy nanofibers-based K+ sensor achieved a high sensitivity of 62 mV decade-1, good selectivity, and solid stability. After being integrated with a temperature sensor, the manufactured wearable sensor realized accurate monitoring of K+ fluctuation in the human sweat.


Asunto(s)
Nanofibras , Polímeros , Potasio , Pirroles , Dispositivos Electrónicos Vestibles , Nanofibras/química , Pirroles/química , Polímeros/química , Potasio/química , Potasio/análisis , Humanos , Técnicas Biosensibles/métodos , Electrones , Iones , Sudor/química , Conductividad Eléctrica
2.
Nano Lett ; 22(1): 196-202, 2022 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-34935386

RESUMEN

Biofuel cells with good biocompatibility are promising to be used as the power source for flexible and wearable bioelectronics. We here report a type of highly flexible and stretchable biofuel cells, which are enabled by textile electrodes of graphene/carbon nanotubes (G/CNTs) composite and polymer hydrogel electrolyte. The CNT array covalently grown from a graphene layer not only can be served as a conducting substrate to immobilize enzyme molecules but also can provide efficient charge transport channels between the enzyme and graphene electrode. As a result, the developed biofuel cells deliver a high open-circuit voltage of 0.65 V and output power density of 64.2 µW cm-2, which are much higher than previously reported results. Benefiting from the unique textile structure of electrodes and the polymer hydrogel electrolyte, the biofuel cells exhibit high retention of power density after 400 bending cycles and even stretched to a high strain of 60%.


Asunto(s)
Fuentes de Energía Bioeléctrica , Nanotubos de Carbono , Electrodos , Electrólitos , Hidrogeles , Nanotubos de Carbono/química , Polímeros , Textiles
3.
Am J Otolaryngol ; 43(3): 103454, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35413544

RESUMEN

OBJECTIVE: To identify the factors predicting postoperative recurrence after cold steel excision for the market trader with idiopathic vocal process granulomas (VPGs). MATERIAL AND METHODS: The market traders with idiopathic VPGs who do not respond to medical treatment were treated by cold steel excision. The factors considered likely to affect the recurrence were evaluated by univariate and multivariate logistic regression. RESULTS: The total of 80 idiopathic VPGs underwent the cold steel excision. All postoperative 6 months, the complete remission rate was 37.5% (30 VPGs) and 50 recurrences developed (62.5%). The recurrence rate was not significantly associated with sex (P = 0.119), side (P = 0.468), VPG size (P = 0.726), LPR (P = 0.293), diabetes mellitus (P = 0.5611), cerebrovascular disease (P = 0.129), or chronic pulmonary disease (P = 0.190). Multivariate logistic regression showed that only vocalization frequency (P = 0.006) and smoking and alcohol consumption (P = 0.001) were independent predictors of recurrence. There was no significant correlation between age and recurrence (P = 0.59). However, recurrence was more common in those aged 51-60 years than those aged ≥61 years (P = 0.019). Of the recurrent 49 VPGs treated conservatively via behavioural modification and oral deanxit, the granulomas disappeared spontaneously in 38 (77.6%) within 6-10 months and in 11 (22.4%) within 2-3 years. CONCLUSIONS: The market traders with VPG would be a high recurrence rate after cold steel excision, the frequency of voice use and smoking and alcohol consumption were significant independent predictors of recurrence. Antidepressant medications and behavioural modification could effectively improve the outcome of VPG.


Asunto(s)
Acero , Voz , Granuloma/etiología , Granuloma/cirugía , Humanos , Estudios Retrospectivos , Fumar , Pliegues Vocales
4.
Nano Lett ; 19(4): 2731-2738, 2019 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-30919635

RESUMEN

Nitric oxide (NO) induces a multitude of antitumor activities, encompassing the induction of apoptosis, sensitization to chemo-, radio-, or immune-therapy, and inhibition of metastasis, drug resistance, angiogenesis, and hypoxia, thus attracting much attention in the area of cancer intervention. To improve the precise targeting and treatment efficacy of NO, a glutathione (GSH)-sensitive NO donor (1,5-bis[(l-proline-1-yl)diazen-1-ium-1,2-diol- O2-yl]-2,4-dinitrobenzene, BPDB) coordinates with iron ions to form the nanoscale coordination polymer (NCP) via a simple precipitation and then partial ion exchange process. The obtained Fe(II)-BNCP shows desirable solubility, biocompatibility, and circulation stability. Quick NO release triggered by high concentrations of GSH in tumor cells improves the specificity of NO release in situ, thus avoiding side effects in other tissues. Meanwhile, under high concentrations of H2O2 in tumors, Fe2+ ions in BPDB-based NCP, named Fe(II)-BNCP, exert Fenton activity to generate hydroxyl radicals (·OH), which is the main contribution for chemodynamic therapy (CDT). In addition, ·O2- generated by the Haber-Weiss reaction of Fe2+ ions with H2O2 can quickly react with NO to produce peroxynitrite anion (ONOO-) that is more cytotoxic than ·O2- or NO only. This synergistic NO-CDT effect has been proved to retard the tumor growth in Heps xenograft ICR mouse models. This work not only implements a synergistic effect of NO-CDT therapy but also offers a simple and efficient strategy to construct a coordination polymer nanomedicine via rationally designed prodrug molecules such as NO donors.


Asunto(s)
Neoplasias Hepáticas/tratamiento farmacológico , Nanomedicina/métodos , Donantes de Óxido Nítrico/química , Óxido Nítrico/química , Animales , Apoptosis/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Línea Celular Tumoral , Dinitrobencenos/química , Glutatión/química , Humanos , Peróxido de Hidrógeno/química , Neoplasias Hepáticas/patología , Óxido Nítrico/biosíntesis , Polímeros/administración & dosificación , Polímeros/síntesis química , Polímeros/química , Profármacos/administración & dosificación , Profármacos/síntesis química , Profármacos/química , Ratas
5.
Beijing Da Xue Xue Bao Yi Xue Ban ; 46(5): 744-80, 2014 Oct 18.
Artículo en Zh | MEDLINE | ID: mdl-25331398

RESUMEN

OBJECTIVE: To develop and investigate the properties of MRI-traceable Eudragit-E liquid embolic agent (MR-E). METHODS: Polyethylene glycol-modified superparamagnetic iron oxides (PEG-SPIO) was synthesized by chemical co-precipitation method. MR-E was prepared by mixing PEG-SPIO and Eudragit-E liquid embolic agent homogeneously. An in vitro MR phantom study was carried out to measure MR traceability of MR-E and to determine the concentration of PEG-SPIO for further studies. The microcatheter deliverability and sol-gel transition process of MR-E were investigated. MR-E was injected into the kidney of a Japanese white big ear rabbit via an angiographic microcatheter, and detected by MRI. RESULTS: A PEG-SPIO concentration of 2 g/L was considered to be suitable for further studies. MR-E was injected through the microcatheter without any difficulty. MR-E instantly solidified on release into saline. Then 0.2 mL of MR-E effectively embolized distal renal arteries, and MR-E could be detected by MRI in the embolized kidney. CONCLUSION: MR-E seems to be a promising MRI-traceable liquid embolic agent.


Asunto(s)
Dextranos/farmacología , Embolización Terapéutica , Metilmetacrilatos/farmacología , Arteria Renal , Animales , Riñón/efectos de los fármacos , Imagen por Resonancia Magnética , Nanopartículas de Magnetita , Fantasmas de Imagen , Conejos
6.
Beijing Da Xue Xue Bao Yi Xue Ban ; 46(4): 629-34, 2014 Aug 18.
Artículo en Zh | MEDLINE | ID: mdl-25131483

RESUMEN

OBJECTIVE: To prepare doxorubicin-loaded polyvinylalcohol-acrylic acid (PVA-AA) microspheres and evaluate properties of this chemoembolic agent. METHODS: PVA-AA microspheres were synthesized by inverse suspension polymerization method and then verified by infrared spectroscopy. drug loading (DL) and entrapment efficiency (EE%) were measured after doxorubicinwas loaded on PVA-AA microspheres. Their morphology and elasticity were investigated by optical microscope, environmental scanning electron microscope and texture analyzer, respectively. T-cell apparatus was used to evaluate the in vitro release behavior of doxorubicin-loaded microspheres.The external carotid of the rabbit was chosen as an embolization site to evaluate the in vivo embolic property of the microspheres. RESULTS: PVA-AA microspheres, which were transparent spheres,turned into red spheres after doxorubicin loading. DL of the microspheres was (20.56 ± 0.69)g/L and (23.25 ± 0.27) g/L,and EE% was 82.22% ± 2.76% and 93.00% ± 1.06% within 20 min and 6 h, respectively. The in vitro release results showed a significantly delayed release of the drug for 10.32% ± 0.47% after 24 h. The Young's modulus was (178.30 ± 12.33) kPa and (213.29 ± 15.61) kPa for blank microspheres and doxorubicin-loaded microspheres, respectively. Both blank microspheres and doxorubicin-loaded microspheres exhibited good elasticity. In vivo embolization showed that 0.3 mL of microspheres could produce distal embolic efficiency. CONCLUSION: The doxorubicin-loaded microspheres are expected to be a promising new chemoembolic agent.


Asunto(s)
Doxorrubicina/química , Portadores de Fármacos/química , Microesferas , Acrilatos , Animales , Elasticidad , Embolización Terapéutica , Alcohol Polivinílico , Conejos
7.
J Hazard Mater ; 469: 133929, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38452672

RESUMEN

Asexual reproduction is one of the most important propagations in aquatic plants. However, there is a lack of information about the growth-limiting mechanisms induced by microplastics on the submerged plant during asexual propagule germination to seedling. Hence, we investigated the effects of two sizes (2 µm, 0.2 µm) and three concentrations (0.5 mg/L, 5 mg/L, and 50 mg/L) of polystyrene microplastics (PSMPs) on Potamogeton crispus turion germination and seedling growth. Both PSMPs sizes were found in P. crispus seedling tissues. Metabolic profile alterations were observed in leaves, particularly affecting secondary metabolic pathways and ATP-binding cassette transporters. Metal elements are indispensable cofactors for photosynthesis; however, alterations in the metabolic profile led to varying degrees of reduced concentrations in magnesium, iron, copper, and zinc within P. crispus. Therefore, the maximum quantum yield of photosystem II significantly decreased in all concentrations with 0.2 µm-PSMPs, and at 50 mg/L with 2 µm-PSMPs. These findings reveal that internalization of microplastics, nutrient absorption inhibition, and metabolic changes contribute to the negative impact on P. crispus seedlings.


Asunto(s)
Germinación , Plantones , Poliestirenos/farmacología , Microplásticos/farmacología , Plásticos
8.
J Perinatol ; 38(4): 332-336, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29282354

RESUMEN

OBJECTIVE: Hypothermia remains a significant problem among very low birth weight (VLBW) infants. The use of occlusive polyethylene plastic bags immediately after birth has been proven to be effective for preterm infants to reduce hypothermia. This study aims to determine whether placing VLBW infants in plastic bags during transport reduces hypothermia. STUDY DESIGN: Study infants were randomly assigned to a standard thermoregulation protocol or to a standard thermoregulation protocol with placement of the torso and lower extremities inside a polyethylene plastic bag during transport. The primary outcome measures were axillary temperature before and after transport and the occurrence of moderate hypothermia upon neonatal intensive care unit admission. RESULT: The 108 VLBW infants recruited into the study were randomized to the plastic bag (n = 54) group or to standard group (n = 54) and had similar baseline characteristics. VLBW infants in the plastic bag group had a lower rate of moderate hypothermia (3.7 vs 27.8%; risk ratio 0.10; confidence interval 0.02-0.46; P < 0.001) and higher axillary temperatures (36.4 ± 0.4 °C vs 35.9 ± 0.9 °C; P = 0.001) upon NICU admission compared to infants receiving standard care. CONCLUSION: Placing VLBW infants in polyethylene plastic bags during transport reduces the occurrence of hypothermia, especially moderate hypothermia.


Asunto(s)
Hipotermia/prevención & control , Recién Nacido de muy Bajo Peso/fisiología , Atención Perinatal/métodos , Polietileno , Transporte de Pacientes , Regulación de la Temperatura Corporal , China , Femenino , Hospitales Pediátricos , Humanos , Hipotermia/etiología , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Modelos Lineales , Masculino
9.
Int J Pharm ; 471(1-2): 285-96, 2014 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-24858389

RESUMEN

New type of liquid embolic agents based on a liquid crystalline material of glyceryl monooleate (GMO) was developed and evaluated in this study. Ternary phase diagram of GMO, water and ethanol was constructed and three isotropic liquids (ILs, GMO:ethanol:water=49:21:30, 60:20:20 and 72:18:10 (w/w/w)) were selected as potential liquid embolic agents, which could spontaneously form viscous gel cast when contacting with water or physiological fluid. The ILs exhibited excellent microcatheter deliverability due to low viscosity, and were proved to successfully block the saline flow when performed in a device to simulate embolization in vitro. The ILs also showed good cytocompatibility on L929 mouse fibroblast cell line. The embolization of ILs to rabbit kidneys was performed successfully under monitoring of digital subtraction angiography (DSA), and embolic degree was affected by the initial formulation composition and used volume. At 5th week after embolization, DSA and computed tomography (CT) confirmed the renal arteries embolized with IL did not recanalize in follow-up period, and an obvious atrophy of the embolized kidney was observed. Therefore, the GMO-based liquid embolic agents showed feasible and effective to embolize, and potential use in clinical interventional embolization therapy.


Asunto(s)
Materiales Biocompatibles/química , Embolización Terapéutica/métodos , Glicéridos/química , Cristales Líquidos/química , Animales , Materiales Biocompatibles/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , Etanol/química , Fibroblastos/efectos de los fármacos , Geles , Glicéridos/toxicidad , Cristales Líquidos/toxicidad , Ratones , Transición de Fase , Conejos , Radiografía , Arteria Renal/diagnóstico por imagen , Arteria Renal/efectos de los fármacos , Viscosidad , Agua/química
10.
Int J Pharm ; 452(1-2): 211-9, 2013 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-23707965

RESUMEN

Embolic agents, such as microparticles, microspheres or beads used in current embolotherapy are mostly radiolucent, which means the agents are invisible under X-ray imaging during and after the process of embolization, and the fate of these particles cannot be precisely assessed. In this research, a radiopaque embolic agent was developed by encapsulating lipiodol in polyvinyl alcohol. The lipiodol-containing polyvinyl alcohol microcapsules (LPMs) were characterized and evaluated for their morphology, size distribution, lipiodol content, lipiodol release, elasticity, and deliverability through catheter. The radiopacity of LPMs in vials and in living mice was both detected by an X-ray imaging system. The biocompatibility of LPMs was investigated with L929 cells and in mice after subcutaneous injection. Embolization of LPMs to a rabbit kidney was performed under digital subtraction angiography (DSA) and the radiopacity of LPMs was verified by computed tomography (CT).


Asunto(s)
Medios de Contraste/administración & dosificación , Alcohol Polivinílico/administración & dosificación , Angiografía de Substracción Digital , Animales , Arterias , Materiales Biocompatibles/administración & dosificación , Materiales Biocompatibles/química , Cápsulas , Cateterismo , Medios de Contraste/química , Elasticidad , Embolización Terapéutica , Aceite Etiodizado/administración & dosificación , Aceite Etiodizado/química , Femenino , Riñón/metabolismo , Ratones , Tamaño de la Partícula , Alcohol Polivinílico/química , Conejos , Tomografía Computarizada por Rayos X
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