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1.
Environ Sci Technol ; 58(29): 13157-13167, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38996057

RESUMEN

Dichloramine (NHCl2) naturally exists in reverse osmosis (RO) permeate due to its application as an antifouling chemical in membrane-based potable reuse treatment. This study investigated mechanisms of background NHCl2 hydrolysis associated with the generation of oxidative radical species in RO permeate, established a kinetic model to predict the oxidative capacity, and examined its removal efficiency on trace organic contaminants in potable reuse. Results showed that NHCl2 hydrolysis generated transient peroxynitrite (ONOO-) and subsequently dissociated into hydroxyl radical (HO•). The maximal HO• exposure was observed at an RO permeate pH of 8.4, higher than that from typical ultraviolet (UV)-based advanced oxidation processes. The HO• exposure during NHCl2 hydrolysis also peaked at a NH2Cl-to-NHCl2 molar ratio of 1:1. The oxidative capacity rapidly degraded 1,4-dioxane, carbamazepine, atenolol, and sulfamethoxazole in RO permeate. Furthermore, background elevated carbonate in fresh RO permeate can convert HO• to carbonate radical (CO3•-). Aeration of the RO permeate removed total carbonate, significantly increased HO• exposure, and enhanced the degradation kinetics of trace organic contaminants. The kinetic model of NHCl2 hydrolysis predicted well the degradation of contaminants in RO permeate. This study provides new mechanistic insights into NHCl2 hydrolysis that contributes to the oxidative degradation of trace organic contaminants in potable reuse systems.


Asunto(s)
Oxidación-Reducción , Purificación del Agua , Hidrólisis , Purificación del Agua/métodos , Membranas Artificiales , Contaminantes Químicos del Agua/química , Cinética
2.
Analyst ; 148(7): 1543-1551, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36880438

RESUMEN

A new method and platform has been developed for direct transfer, electrophoretic separation, and pre-concentration of swabbed samples using the principles of thread-based electrofluidics. A direct electrokinetic injection has been observed for a variety of analytes ranging from small molecules to proteins. The effect of physicochemical interactions of the analyte with the swab and the thread on the transfer efficiency has been studied by exploring different swab and thread combinations. For fluorescein, using a polyurethane swab, 98% and 94% transfer efficiencies were observed on mercerised cotton and nylon thread, while only 80% transfer efficiency was observed on polyester thread, respectively. A 97% transfer of fluorescein was observed on the nylon thread when a flocked nylon swab was used, while only 47% transfer was observed when a cotton swab was used. A successful transfer has been observed for both liquid and dry samples from either pre-wetted or dry swabs in both the presence and absence of any surrounding electrolytes. The platform has been further adapted for multiplexed analysis, where a sample from a single swab was transferred onto two parallel thread systems with ca. 50% distribution between them. The method has been validated for transfer, separation, and pre-concentration of DNA from blood. It has also been successfully used to directly analyse dried blood samples using a commercial sampling device, Neoteryx Mitra.


Asunto(s)
Nylons , Manejo de Especímenes , Manejo de Especímenes/métodos , ADN , Fluoresceínas
3.
J Am Chem Soc ; 144(34): 15497-15508, 2022 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-35979963

RESUMEN

Bicontinuous porous materials, which possess 3D interconnected pore channels facilitating a smooth mass transport, have attracted much interest in the fields of energy and catalysis. However, their synthesis remains very challenging. We report a general approach, using polymer cubosomes as the template, for the controllable synthesis of bicontinuous porous polymers with an ordered single primitive (SP) cubic structure, including polypyrrole (SP-PPy), poly-m-phenylenediamine (SP-PmPD), and polydopamine (SP-PDA). Specifically, the resultant SP-PPy had a unit cell parameter of 99 nm, pore diameter of 45 nm, and specific surface area of approximately 60 m2·g-1. As a proof of concept, the I2-adsorbed SP-PPy was employed as the cathode materials of newly emerged Na-I2 batteries, which delivered a record-high specific capacity (235 mA·h·g-1 at 0.5 C), excellent rate capability, and cycling stability (with a low capacity decay of 0.12% per cycle within 400 cycles at 1 C). The advantageous contributions of the bicontinuous structure and I3- adsorption mechanism of SP-PPy were revealed by a combination of ion diffusion experiments and theoretical calculations. This study opens a new avenue for the synthesis of porous polymers with new topologies, broadens the spectrum of bicontinuous-structured materials, and also develops a novel potential application for porous polymers.


Asunto(s)
Yodo , Polímeros , Polímeros/química , Porosidad , Pirroles/química , Sodio
4.
Anesthesiology ; 136(4): 551-566, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35226725

RESUMEN

BACKGROUND: Postoperative pulmonary complications are common. Aging and respiratory disease provoke airway hyperresponsiveness, high-risk surgery induces diaphragmatic dysfunction, and general anesthesia contributes to atelectasis and peripheral airway injury. This study therefore tested the hypothesis that inhalation of penehyclidine, a long-acting muscarinic antagonist, reduces the incidence of pulmonary complications in high-risk patients over the initial 30 postoperative days. METHODS: This single-center double-blind trial enrolled 864 patients age over 50 yr who were scheduled for major upper-abdominal or noncardiac thoracic surgery lasting 2 h or more and who had an Assess Respiratory Risk in Surgical Patients in Catalonia score of 45 or higher. The patients were randomly assigned to placebo or prophylactic penehyclidine inhalation from the night before surgery through postoperative day 2 at 12-h intervals. The primary outcome was the incidence of a composite of pulmonary complications within 30 postoperative days, including respiratory infection, respiratory failure, pleural effusion, atelectasis, pneumothorax, bronchospasm, and aspiration pneumonitis. RESULTS: A total of 826 patients (mean age, 64 yr; 63% male) were included in the intention-to-treat analysis. A composite of pulmonary complications was less common in patients assigned to penehyclidine (18.9% [79 of 417]) than those receiving the placebo (26.4% [108 of 409]; relative risk, 0.72; 95% CI, 0.56 to 0.93; P = 0.010; number needed to treat, 13). Bronchospasm was less common in penehyclidine than placebo patients: 1.4% (6 of 417) versus 4.4% (18 of 409; relative risk, 0.327; 95% CI, 0.131 to 0.82; P = 0.011). None of the other individual pulmonary complications differed significantly. Peak airway pressures greater than 40 cm H2O were also less common in patients given penehyclidine: 1.9% (8 of 432) versus 4.9% (21 of 432; relative risk, 0.381; 95% CI, 0.171 to 0.85; P = 0.014). The incidence of other adverse events, including dry mouth and delirium, that were potentially related to penehyclidine inhalation did not differ between the groups. CONCLUSIONS: In high-risk patients having major upper-abdominal or noncardiac thoracic surgery, prophylactic penehyclidine inhalation reduced the incidence of pulmonary complications without provoking complications.


Asunto(s)
Espasmo Bronquial , Atelectasia Pulmonar , Espasmo Bronquial/inducido químicamente , Espasmo Bronquial/complicaciones , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Atelectasia Pulmonar/complicaciones , Quinuclidinas/efectos adversos , Quinuclidinas/uso terapéutico
5.
Nano Lett ; 21(6): 2690-2698, 2021 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-33543616

RESUMEN

Although injectable hydrogel microsphere has demonstrated tremendous promise in clinical applications, local overactive inflammation in degenerative diseases could jeopardize biomaterial implantation's therapeutic efficacy. Herein, an injectable "peptide-cell-hydrogel" microsphere was constructed by covalently coupling of APETx2 and further loading of nucleus pulposus cells, which could inhibit local inflammatory cytokine storms to regulate the metabolic balance of ECM in vitro. The covalent coupling of APETx2 preserved the biocompatibility of the microspheres and achieved a controlled release of APETx2 for more than 28 days in an acidic environment. By delivering "peptide-cell-hydrogel" microspheres to a rat degenerative intervertebral disc at 4 weeks, the expression of ASIC-3 and IL-1ß was significantly decreased for 3.53-fold and 7.29-fold, respectively. Also, the content of ECM was significantly recovered at 8 weeks. In summary, the proposed strategy provides an effective approach for tissue regeneration under overactive inflammatory responses.


Asunto(s)
Hidrogeles , Núcleo Pulposo , Animales , Materiales Biocompatibles , Inflamación/tratamiento farmacológico , Microesferas , Ratas
6.
Macromol Rapid Commun ; 36(14): 1362-7, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25962480

RESUMEN

For anion exchange membranes (AEMs), achieving efficient hydroxide conductivity without excessive hydrophilicity presents a challenge. Hence, new strategies for constructing mechanically strengthened and hydroxide conductive (especially at controlled humidity) membranes are critical for developing better AEMs. Macromolecular modification involving ylide chemistry (Wittig reaction) for the fabrication of novel AEMs with an interpenetrating polymer network structure is reported. The macromolecular modification is cost effective, facile, and based on a one-pot synthesis. AEM water uptake is reduced to 3.6 wt% and a high hydroxide conductivity (69.7 mS cm(-1) , 90 °C) is achieved simultaneously. More importantly, the membrane exhibits similar tensile strength (>35 MPa) and comparable flexibility in both dry and wet states. These AEMs could find further applications within anion exchange membrane fuel cells with low humidity or photoelectric assemblies.


Asunto(s)
Membranas Artificiales , Aniones/química , Fuentes de Energía Bioeléctrica , Conductividad Eléctrica , Electrodos , Hidróxidos/química , Intercambio Iónico , Éteres Fenílicos/química , Polímeros/química , Resistencia a la Tracción , Agua/química
7.
Can J Anaesth ; 62(7): 816-29, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25851018

RESUMEN

PURPOSE: Shivering is a frequent complication in the postoperative period. The aim of the current meta-analysis was to assess the efficacy of dexmedetomidine on postoperative shivering. METHODS: Two researchers independently searched PubMed, EMBASE and the Cochrane Central Register of Controlled Trials for controlled clinical trials. The meta-analysis was performed by Review Manager. RESULTS: Thirty-nine trials with 2,478 patients were included in this meta-analysis. Dexmedetomidine reduced postoperative shivering compared with placebo (risk ratio [RR] = 0.26; 95% confidence interval [CI]: 0.20 to 0.34), with a minimum effective dose of 0.5 µg·kg(-1) (RR = 0.36; 95% CI: 0.21 to 0.60). The anti-shivering effect can be achieved both intravenously and epidurally when administered within two hours prior to the end of surgery. The efficacy of dexmedetomidine was similar to widely used anti-shivering agents, such as fentanyl, meperidine, tramadol, clonidine and so on; however, dexmedetomidine may increase the incidence of sedation, hypotension, bradycardia and dry mouth. CONCLUSIONS: The present meta-analysis indicates that dexmedetomidine shows superiority over placebo, but not over other anti-shivering agents. Therefore, considering its high price and potential adverse events, dexmedetomidine may not be appropriate solely for the purpose of the prevention of postoperative shivering.


Asunto(s)
Dexmedetomidina/uso terapéutico , Complicaciones Posoperatorias/tratamiento farmacológico , Tiritona/efectos de los fármacos , Agonistas de Receptores Adrenérgicos alfa 2/administración & dosificación , Agonistas de Receptores Adrenérgicos alfa 2/efectos adversos , Agonistas de Receptores Adrenérgicos alfa 2/uso terapéutico , Dexmedetomidina/administración & dosificación , Dexmedetomidina/efectos adversos , Humanos
8.
Front Biosci (Landmark Ed) ; 29(2): 90, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38420791

RESUMEN

BACKGROUND: Deguelin (DGL) is a natural flavonoid reported to exhibit antitumor effects in breast cancer (BC). PEG-PCL (Polyethylene Glycol- Polycaprolactone), as polymeric micelles, has biodegradability and biocompatibility. The aim of this study was to investigate whether the nanoparticular delivery system, PEG-PCL could improve the bioavailability of DGL for suppressing proliferation of BC cells. METHODS: PEG-PCL polymers were first prepared by ring-opening polymerization, and DGL and paclitaxel (PTX)-loaded PEG-PCL nano-micelles were formulated via the film dispersion method. The composition and molecular weight of PEG-PCL were analyzed by nuclear magnetic resonance and fourier Transform infrared spectroscopy (FTIR) spectra. Particle size, surface potential and hemolytic activity of micelles were assessed by dynamic light scattering, transmission electron microscopy and hemolysis assay, respectively. Then proliferation and apoptosis of MDA-MB-231 and MDA-MB-468 cells were tested with Edu staining, CCK-8, TUNEL staining, and Flow cytometer. Caspase 3 expression was also assessed by Western blot. RESULTS: Our results first indicated that PEG2000-PCL2000 was successfully synthesized. DGL and PTX-loaded PEG-PCL nano-micelles were rounded in shape with a particle size of 35.78 ± 0.35 nm and a surface potential of 2.84 ± 0.27 mV. The micelles had minimal hemolytic activity. Besides, we proved that DGL and PTX-loaded PEG-PCL nano-micelles could suppress proliferation and induce apoptosis in BC cells. The DGL and PTX-loaded PEG-PCL nano-micelles constructed in this study had a prominent inhibitory role on proliferation and a remarkable promotional role on apoptosis in BC cells. CONCLUSIONS: This study proposes that nano-micelles formed by PEG-PCL can enhance the cytotoxicity of Paclitaxel against breast cancer cells, and concurrently, the loading of Deguelin may further inhibit cell proliferation. This presents a potential for the development of a novel therapeutic strategy.


Asunto(s)
Neoplasias de la Mama , Paclitaxel , Rotenona/análogos & derivados , Humanos , Femenino , Paclitaxel/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Micelas , Polietilenglicoles/química , Polietilenglicoles/farmacología , Polietilenglicoles/uso terapéutico , Polímeros , Apoptosis , Línea Celular Tumoral
9.
Lab Chip ; 24(4): 776-786, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38197467

RESUMEN

Thread-based microfluidic colorimetric sensors have been deemed a potential tool that may be incorporated into textiles for non-invasive sweat analysis. Nevertheless, their poor performance significantly limits their practical uses in sweat glucose detection down to 20 µM. Herein, a microfluidic glucose sensing device containing a salt-responsive thread is developed for the highly sensitive detection of glucose in human sweat. By grafting a zwitterionic polymer brush-which could react to ionic strength by changing the conformation of the polymer chains from the collapsing state to the stretching state-onto the cotton thread, the salt-responsive thread was created. Compared to the pristine cotton thread, the modified thread has better ion-capture capabilities, a more noticeable swelling effect, and a higher ability to absorb water. These enable a significant enrichment of glucose when the saline solution passes through it. The salt-responsive thread was employed to construct a thread/paper-based microfluidic sensing device for the monitoring of glucose in artificial sweat, exhibiting a sensitivity of -0.255 µM-1 and a detection limit of 14.7 µM. In comparison to the pristine cotton thread-based device, the performance is significantly superior. Using a hydrophobic fabric and salt-responsive threads, a glucose-sensing headband was prepared for on-body sweat glucose monitoring. With the use of a smartphone-based image analysis system, the headband can detect the concentration of glucose in a volunteer's perspiration. Using the thread-based salt-responsive zwitterionic polymer brush might offer a novel approach to creating wearable sweat sensors with extremely high sensitivity.


Asunto(s)
Técnicas Biosensibles , Sudor , Humanos , Sudor/química , Microfluídica , Automonitorización de la Glucosa Sanguínea , Glucemia/análisis , Glucosa/análisis , Polímeros
10.
Chemistry ; 19(20): 6368-73, 2013 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-23520127

RESUMEN

Based on the competitive host-guest interaction between a ß-cyclodextrin/poly(N-acetylaniline)/electrogenerated-graphene (ß-CD/PNAANI/EG) film and probe or target molecules, a new dual-signalling electrochemical sensing method has been developed for the sensitive and selective determination of organic pollutants. As a model system, rhodamine B (RhB) and 1-aminopyrene (1-AP) were adopted as the probe and target molecules, respectively. Due to the host-guest interaction, RhB molecules can enter into the hydrophobic inner cavity of ß-CD, and the ß-CD/PNAANI/EG-modified glassy carbon electrode displays a remarkable oxidation peak due to RhB. In the presence of 1-AP, competitive association to ß-CD occurs and the RhB molecules are displaced by 1-AP. This results in a decreased oxidation peak current of RhB and the appearance of an oxidation peak current for 1-AP, and the changes of these signals correlate linearly with the concentration of 1-AP. When the value ΔI(1-AP)+∣ΔI(RhB)∣ (ΔI(1-AP) and ΔI(RhB) are the change values of the oxidation peak currents of 1-AP and RhB, respectively) is used as the response signal to quantitatively determine the concentration of 1-AP, the detection limit is much lower than that given by using ΔI(1-AP) or ΔI(RhB) as the response signal. This dual-signalling sensor can provide more sensitive target recognition and will have important applications in the sensitive and selective electrochemical determination of electroactive organic pollutants.


Asunto(s)
Acetanilidas/química , Contaminantes Ambientales/análisis , Grafito/química , Hidrocarburos Aromáticos/análisis , Modelos Químicos , Polímeros/química , Pirenos/análisis , Rodaminas/análisis , beta-Ciclodextrinas/química , Carbono/química , Pirenos/química , Rodaminas/química , Espectroscopía Infrarroja por Transformada de Fourier
11.
J Mater Chem B ; 11(4): 905-913, 2023 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-36598076

RESUMEN

High performance hydrogels have essential applications in many fields such as tissue engineering and soft robot. Herein, we develop an impact resistant hydrogel composed of bicontinuous structures of polymer-hard phase and polymer-soft phase. This unique bicontinuous phase structure is formed by modulating various hydrogen bonding interactions. During loading, the polymer-hard phase is broken accompanied by the dissociation of hydrogen bonds to dissipate energy, while the polymer-soft phase distributes the load to avoid stress concentration, thus enabling the bicontinuous hydrogel to achieve excellent strength and toughness simultaneously. Furthermore, the fracture of hierarchical energy dissipation structures efficiently reduces impact strength and increases buffer time. Owing to the synergy of the bicontinuous phase structure and hierarchical energy dissipation, the resulting bicontinuous hydrogel remains intact even if it undergoes impact at a strain rate of ∼13 000 s-1. Based on these findings, it is expected that the bicontinuous hydrogel has a potential application in the field of articular cartilage repair.


Asunto(s)
Cartílago Articular , Hidrogeles , Hidrogeles/química , Ingeniería de Tejidos , Polímeros/química , Enlace de Hidrógeno
12.
J Mater Chem B ; 11(24): 5514-5522, 2023 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-36655770

RESUMEN

Photo-reactive polymers are important for biomaterials, including devices with a 3D-structure. Here, different types of photo-reactive polymers were prepared and utilised for immobilisation of growth factors. They were synthesised by conjugation of gelatin with the azidophenyl group or by copolymerisation of the azidophenyl group-coupled methacrylate with poly(ethylene glycol) methacrylate. The azidophenyl content and the zeta potential of the prepared polymers were measured. After spin coating of polymers, the thickness and the water contact angle of coated layers were measured. The amount of the immobilised epidermal growth factor (EGF) was determined using fluorescence labelling. Cell adhesion responded to the nature of photo-reactive polymers but did not depend on the immobilised EGF. However, cell growth was dependent on the amount of immobilised EGF and was significantly affected by the nature of photo-reactive polymers. The study shows that the properties of the photo-immobilisation matrix significantly influence the biological activity.


Asunto(s)
Factor de Crecimiento Epidérmico , Polímeros , Polímeros/química , Polietilenglicoles/química , Metacrilatos/química
13.
Shanghai Kou Qiang Yi Xue ; 32(3): 246-250, 2023 Jun.
Artículo en Zh | MEDLINE | ID: mdl-37803977

RESUMEN

PURPOSE: To evaluate the in vitro biocompatibility and antibacterial activity of a new type of strontium silicate-based C-Root SP root canal sealer, and to provide a reference for clinical selection of sealers. METHODS: C-Root SP, iRoot SP and AH Plus extracts were prepared, L929 cells and MC3T3-E1 cells were cultured in vitro, and the cytotoxicity and osteogenic potential of the three sealers were compared. Fresh sealers were mixed with Enterococcus faecalis solution and the antibacterial activity of the sealer was determined by direct contact text (DCT). SPSS 25.0 software package was used for statistical analysis. RESULTS: At 24, 48, and 72 h, the cytotoxicity of the sealers in each group were significantly different (P<0.01). Compared with AH Plus, the cytotoxicity of C-Root SP was lower (P<0.01). C-Root SP was superior to AH Plus in promoting the activity of alkaline phosphatase(ALP) (P<0.01). iRoot SP was the strongest in promoting the formation of mineralized nodules, followed by C-Root SP, and the weakest was AH Plus(P<0.01). C-Root SP inhibited the growth of Enterococcus faecalis, and its antibacterial rate was significantly higher than AH Plus(P<0.01). CONCLUSIONS: The strontium silicate root canal sealer C-Root SP has low cytotoxicity, certain osteogenic potential and antibacterial activity against Enterococcus faecalis, so it can be used for root canal filling.


Asunto(s)
Cavidad Pulpar , Materiales de Obturación del Conducto Radicular , Materiales de Obturación del Conducto Radicular/farmacología , Silicatos/farmacología , Antibacterianos/farmacología , Estroncio , Resinas Epoxi/farmacología , Ensayo de Materiales
14.
Exp Parasitol ; 130(1): 91-4, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22033076

RESUMEN

In this study, we evaluated four methods to separate and purify Toxoplasma gondii tachyzoites from in vivo and in vitro culture systems, including trypsin digestion, purification with a 3-µm filter, CF-11 cellulose purification, and Percoll purification. Our results indicate that both purification with a 3-µm filter and CF11 cellulose purification methods remove leukocytes or HeLa cells, and can therefore be used as candidate methods for the purification of in vivo and in vitro culture products. Trypsin digestion had a high tachyzoite recovery rate, but 22.35% of leukocytes and 69.64% of HeLa cells remained in the purified products. Percoll solution [30% (v/v)] also had a high tachyzoite recovery rate, but 3.44% of leukocytes and 61.61% of HeLa cells remained in the purified products. The 40% Percoll solution was also a candidate method for purifying tachyzoites from in vivo culture products, with a 65.45% tachyzoite recovery rate and without leukocytes.


Asunto(s)
Toxoplasma/aislamiento & purificación , Animales , Celulosa , Centrifugación , Eritrocitos/parasitología , Filtración , Células HeLa , Humanos , Leucocitos/parasitología , Ratones , Povidona , Dióxido de Silicio , Tripsina/metabolismo
15.
Zhong Yao Cai ; 35(10): 1674-9, 2012 Oct.
Artículo en Zh | MEDLINE | ID: mdl-23627137

RESUMEN

OBJECTIVE: To prepare poly(lactide-co-glycolide) (PLGA) microspheres containing Oxymatrine (OMT-PLGA-MS) and study their release characteristics in vitro. METHODS: OMT-PLGA-MS was prepared with PLGA as carriers using double emulsion solvent evaporation method (W/O/W). The preparation technology of microspheres was optimized by orthogonal design, and the microspheres were characterized in terms of morphology, the rate of drug loading, encapsulation efficiency, and in vitro drug release. RESULTS: The formed microspheres were spherical with smooth surfaces and the average size was (98.3 +/- 3.4) microm. The encapsulation efficiency and rate of drug loading were (70.14 +/- 3.47)% and (21.59 +/- 1.07)%, respectively. In vitro release study revealed that 84.63% of OMT was released from OMT-PLGA-MS in 240 hours, and the Higuchi model fitted OMT release pattern best. CONCLUSION: OMT-PLGA-MS is prepared successfully and shows good sustained release characteristics.


Asunto(s)
Alcaloides/administración & dosificación , Alcaloides/farmacocinética , Composición de Medicamentos/métodos , Ácido Láctico/química , Ácido Poliglicólico/química , Quinolizinas/administración & dosificación , Quinolizinas/farmacocinética , Alcaloides/química , Preparaciones de Acción Retardada , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Emulsiones/química , Microscopía Electrónica de Rastreo , Microesferas , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Quinolizinas/química , Solventes/química , Sophora/química
16.
ACS Appl Mater Interfaces ; 14(3): 3849-3863, 2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-35019259

RESUMEN

Nitric oxide (NO) is an endogenous gasotransmitter regulating alternative physiological processes in the cardiovascular system. To achieve translational application of NO, continued efforts are made on the development of orally active NO prodrugs for long-term treatment of chronic cardiovascular diseases. Herein, immobilization of NO-delivery [Fe2(µ-SCH2CH2COOH)2(NO)4] (DNIC-2) onto MIL-88B, a metal-organic framework (MOF) consisting of biocompatible Fe3+ and 1,4-benzenedicarboxylate (BDC), was performed to prepare a DNIC@MOF microrod for enhanced oral delivery of NO. In simulated gastric fluid, protonation of the BDC linker in DNIC@MOF initiates its transformation into a DNIC@tMOF microrod, which consisted of DNIC-2 well dispersed and confined within the BDC-based framework. Moreover, subsequent deprotonation of the BDC-based framework in DNIC@tMOF under simulated intestinal conditions promotes the release of DNIC-2 and NO. Of importance, this discovery of transformer-like DNIC@MOF provides a parallel insight into its stepwise transformation into DNIC@tMOF in the stomach followed by subsequent conversion into molecular DNIC-2 in the small intestine and release of NO in the bloodstream of mice. In comparison with acid-sensitive DNIC-2, oral administration of DNIC@MOF results in a 2.2-fold increase in the oral bioavailability of NO to 65.7% in mice and an effective reduction of systolic blood pressure (SBP) to a ΔSBP of 60.9 ± 4.7 mmHg in spontaneously hypertensive rats for 12 h.


Asunto(s)
Materiales Biocompatibles/farmacología , Estructuras Metalorgánicas/farmacología , Óxido Nítrico/química , Profármacos/farmacología , Administración Oral , Animales , Materiales Biocompatibles/administración & dosificación , Presión Sanguínea/efectos de los fármacos , Electrodos , Concentración de Iones de Hidrógeno , Ensayo de Materiales , Estructuras Metalorgánicas/administración & dosificación , Ratones , Óxido Nítrico/administración & dosificación , Tamaño de la Partícula , Profármacos/química , Propiedades de Superficie
17.
Lab Chip ; 21(17): 3338-3351, 2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-34231640

RESUMEN

Additive manufacturing (3D printing) offers a flexible approach for the production of bespoke microfluidic structures such as the electroosmotic pump. Here a readily accessible fused filament fabrication (FFF) 3D printing technique has been employed for the first time to produce microcapillary structures using low cost thermoplastics in a scalable electroosmotic pump application. Capillary structures were formed using a negative space 3D printing approach to deposit longitudinal filament arrangements with polylactic acid (PLA) in either "face-centre cubic" or "body-centre cubic" arrangements, where the voids deliberately formed within the deposited structure act as functional micro-capillaries. These 3D printed capillary structures were shown to be capable of functioning as a simple electroosmotic pump (EOP), where the maximum flow rate of a single capillary EOP was up to 1.0 µl min-1 at electric fields of up to 750 V cm-1. Importantly, higher flow rates were readily achieved by printing parallel multiplexed capillary arrays.


Asunto(s)
Poliésteres , Impresión Tridimensional
18.
ACS Appl Mater Interfaces ; 13(37): 43925-43936, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34499485

RESUMEN

Chemodynamic therapy (CDT) that utilizes Fenton-type reactions to convert endogenous hydrogen peroxide (H2O2) into hydroxyl radicals (•OH) is a promising strategy in anticancer treatment, but the overexpression of glutathione (GSH) and limited endogenous H2O2 make the efficiency of CDT unsatisfactory. Here, an intelligent nanoplatform CuO2@mPDA/DOX-HA (CPPDH), which induced the depletion of GSH and the self-supply of H2O2, was proposed. When CPPDH entered tumor cells through the targeting effect of hyaluronic acid (HA), a release of Cu2+ and produced H2O2 were triggered by the acidic environment of lysosomes. Then, the Cu2+ was reduced by GSH to Cu+, and the Cu+ catalyzed H2O2 to produce •OH. The generation of •OH could be distinctly enhanced by the GSH depletion and H2O2 self-sufficiency. Besides, an outstanding photothermal therapy (PTT) effect could be stimulated by NIR irradiation on mesoporous polydopamine (mPDA). Meanwhile, mPDA was an excellent photoacoustic reagent, which could monitor the delivery of nanocomposite materials through photoacoustic (PA) imaging. Moreover, the successful delivery of doxorubicin (DOX) realized the integration of chemotherapy, PTT, and CDT. This strategy could solve the problem of insufficient CDT efficacy caused by the limited H2O2 and overexpression of GSH. This multifunctional nanoplatform may open a broad path for self-boosting CDT and synergistic therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Portadores de Fármacos/uso terapéutico , Glutatión/metabolismo , Peróxido de Hidrógeno/metabolismo , Nanosferas/uso terapéutico , Neoplasias/tratamiento farmacológico , Antineoplásicos/farmacología , Cobre/química , Cobre/uso terapéutico , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Portadores de Fármacos/síntesis química , Quimioterapia , Células HeLa , Humanos , Ácido Hialurónico/química , Indoles/química , Nanosferas/química , Neoplasias/metabolismo , Terapia Fototérmica , Polímeros/química , Puntos Cuánticos/química , Puntos Cuánticos/uso terapéutico
19.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 41(4): 656-9, 2010 Jul.
Artículo en Zh | MEDLINE | ID: mdl-20848790

RESUMEN

OBJECTIVE: To investigate the feasibility and possible mechanism of non traditional hepatic lobectomy using nitinol alloy net blocker of biliary intrahepatic duct. METHODS: Biliary intrahepatic ducts of the experimental pigs were blocked with and without dissepiment blockers. The histological changes and expressions of TGF-betal and TIMP-1 in the livers were compared. RESULTS: Blockage of biliary intrahepatic duct using nitinol alloy net blocker without dissepiment resulted in obvious atrophy of the focus liver. The mean weight and size of the focus liver was only 1/4 of the controls (P < 0.05), with liver cells almost completely taken by collagen fibers. Higher expressions of TGF-beta1 and TIMP-1 were found in the group without dissepiment than in the group with dissepiments (P < 0.05). CONCLUSION: Using nitinol alloy net blocker for selective hepatic lobectomy is as effective as traditional hepatic lobectomy. It may offer a new way for treating intrahepatic bile duct stones.


Asunto(s)
Conductos Biliares Intrahepáticos/cirugía , Colestasis Intrahepática/terapia , Hepatectomía/métodos , Aleaciones , Animales , Constricción , Embolización Terapéutica , Femenino , Masculino , Distribución Aleatoria , Porcinos
20.
Chemosphere ; 252: 126534, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32224359

RESUMEN

Passive sampling techniques have been widely used to determine the dissolved concentration profiles of hydrophobic organic compounds (HOCs) in sediment porewater. However, the effects of having a protection for the passive sampler on profiling HOCs concentrations in sediment porewater, especially in deep sediment, have remained unclear. To address this issue, low density polyethylene passive samplers with and without protectors, which consisted of glass fiber filter and porous stainless steel shield, were simultaneously deployed in sediment of the Dongjiang River, South China. The results showed that the protectors retarded the dissipation of performance reference compounds (PRCs) from the sampler by a factor of 2-9. The protectors seemed to exert a negligible effect on the measured concentrations of PAHs, BDE-47, and BDE-99 in surficial sediment porewater (0-14 cm depth) from both samplers. However, the sediment porewater concentration profiles of PAHs and BDE-47 from the sampler with protectors were in agreement with those normalized by dry weight in deep sediment (16-34 cm depth), indicating that a diffusion layer established by the protectors may minimize the probability of local depletion of the target analytes in deep sediment. In addition, the log Koc values of PAHs, BDE-47, and BDE-99 exhibited a slight increasing trend with sediment depth. This finding suggested that in situ passive sampling techniques could be a feasible tool in determining the site-specific log Koc values of HOCs at different sediment depths.


Asunto(s)
Contaminantes Químicos del Agua/análisis , China , Difusión , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Éteres Difenilos Halogenados , Interacciones Hidrofóbicas e Hidrofílicas , Compuestos Orgánicos , Hidrocarburos Policíclicos Aromáticos/análisis , Polietileno/química , Porosidad , Ríos/química
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