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1.
Inorg Chem ; 61(27): 10393-10401, 2022 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-35765964

RESUMEN

Hierarchically porous metal-organic frameworks (HP-MOFs), dominating both the micro- and mesoporous regimes, show high potentials in various applications especially those involving bulky biomolecules. The templating method has been proven to be effective in the fabrication of HP-MOFs; however, complicated synthetic systems containing solvents, templates, and additives are frequently employed. Here we report the first example of designing a poly(ethylene glycol)-based alkylammonium and bromide multifunctional ionic liquid (IL) as a solitary medium to construct HP-MOFs, avoiding the involvement of any additional media. Besides the ready solubilization of MOF precursors in the multifunctional IL due to a poly(ethylene glycol) chain as the solubilizer, the ionic moiety facilitates electrostatic interaction to create a templating effect. Hence, UiO-66 with hierarchical porosity has been successfully fabricated, and such a methodology can also be applied to the construction of other HP-MOFs. The resultant HP-UiO-66 is efficient in the encapsulation of bulky biomolecule cytochrome c, and the adsorption capacity is obviously superior to that of the microporous counterpart.


Asunto(s)
Líquidos Iónicos , Estructuras Metalorgánicas , Ácidos Ftálicos , Polietilenglicoles , Porosidad
2.
Plant Mol Biol ; 104(4-5): 513-527, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32833149

RESUMEN

KEY MESSAGE: Os4BGlu14, a monolignol ß-glucosidase, plays a negative role in seed longevity by affecting primary metabolism during seed development and aging. Seed longevity is a crucial trait in agriculture and in the conservation of germplasm resources. ß-Glucosidases (BGlus) are multifunctional enzymes that affect plant growth and their adaptation to the environment. The function of rice BGlus in seed longevity, however, remains unknown. We report here that Os4BGlu14, a rice ß-Glucosidase, negatively affected seed longevity during accelerated aging. Os4BGlu14 was highly expressed in rice embryos and induced by accelerated aging. Compared to the wild type, rice lines overexpressing Os4BGlu14 had significantly greater grain length, but smaller grain width and thickness. Overexpressing (OE) lines also showed lower starch but higher glucose contents. After accelerated aging treatment, OE lines displayed a significantly lower germination percentage than the wild type. Additionally, these lines had higher lignin accumulation before and after accelerated aging. Metabolome analysis detected 217 metabolites in untreated and aged rice seeds. Comparison of the differential metabolites between WT and OE5 revealed that ten key metabolites, four of which (e.g., uridine 5'-diphosphoglucose-glucose, UDPG) were increased, while the other six (e.g., γ-aminobutyric acid and methionine) were decreased, might be the crucial factors that lead to seed deterioration. Further analysis confirmed higher UDPG levels and more severe programmed cell death in OE lines than in the wild type. Furthermore, OE lines presented a lower germination rate after abscisic acid and paclobutrazol treatment during germination, compared to the wild type. Our study provides a basis for understanding the function of Os4BGlu14 in seed longevity in rice.


Asunto(s)
Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Semillas/fisiología , beta-Glucosidasa/genética , Ácido Abscísico/farmacología , Muerte Celular , Regulación de la Expresión Génica de las Plantas , Germinación/efectos de los fármacos , Lignina/genética , Lignina/metabolismo , Metaboloma , Estrés Oxidativo/fisiología , Células Vegetales/fisiología , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Semillas/metabolismo , Uridina Difosfato Glucosa/metabolismo , beta-Glucosidasa/metabolismo
3.
Mikrochim Acta ; 187(7): 390, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32548791

RESUMEN

A nanocomposite based on nanofibrillar cellulose (NFC) coated with gold-silver (core-shell) nanoparticles (Au@Ag NPs) was developed as a novel surface-enhanced Raman spectroscopy (SERS) substrate. SERS performance of NFC/Au@Ag NP nanocomposite was tested by 4-mercaptobenzoic acid. The cellulose nanofibril network was a suitable platform that allowed Au@Ag NPs to be evenly distributed and stabilized over the substrate, providing more SERS hotspots for the measurement. Two pesticides, thiram and paraquat, were successfully detected either individually or as a mixture in lettuce by SERS coupled with the nanocomposite. Strong Raman scattering signals for both thiram and paraquat were obtained within a Raman shift range of 400-2000 cm-1 and a Raman intensity ~ 8 times higher than those acquired by NFC/Au NP nanocomposite. Characteristic peaks were clearly observable in all SERS spectra even at a low concentration of 10 µg/L of pesticides. Limit of detection values of 71 and 46 µg/L were obtained for thiram and paraquat, respectively. Satisfactory SERS performance, reproducibility, and sensitivity of NFC/Au@Ag NP nanocomposite validate its applicability for real-world analysis to monitor pesticides and other contaminants in complex food matrices within a short acquisition time. Graphical abstract.


Asunto(s)
Celulosa/química , Lactuca/química , Nanopartículas del Metal/química , Nanocompuestos/química , Paraquat/análisis , Tiram/análisis , Oro/química , Límite de Detección , Plaguicidas/análisis , Reproducibilidad de los Resultados , Plata/química , Espectrometría Raman
4.
Small ; 15(47): e1903880, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31588682

RESUMEN

Endophthalmitis, derived from the infections of pathogens, is a common complication during the use of ophthalmology-related biomaterials and after ophthalmic surgery. Herein, aiming at efficient photodynamic therapy (PDT) of bacterial infections and biofilm eradication of endophthalmitis, a pH-responsive zeolitic imidazolate framework-8-polyacrylic acid (ZIF-8-PAA) material is constructed for bacterial infection-targeted delivery of ammonium methylbenzene blue (MB), a broad-spectrum photosensitizer antibacterial agent. Polyacrylic acid (PAA) is incorporated into the system to achieve higher pH responsiveness and better drug loading capacity. MB-loaded ZIF-8-PAA nanoparticles are modified with AgNO3 /dopamine for in situ reduction of AgNO3 to silver nanoparticles (AgNPs), followed by a secondary modification with vancomycin/NH2 -polyethylene glycol (Van/NH2 -PEG), leading to the formation of a composite nanomaterial, ZIF-8-PAA-MB@AgNPs@Van-PEG. Dynamic light scattering, transmission electron microscopy, and UV-vis spectral analysis are used to explore the nanoparticles synthesis, drug loading and release, and related material properties. In terms of biological performance, in vitro antibacterial studies against three kinds of bacteria, i.e., Escherichia coli, Staphylococcus aureus, and methicillin-resistant S. aureus, suggest an obvious superiority of PDT/AgNPs to any single strategy. Both in vitro retinal pigment epithelium cellular biocompatibility experiments and in vivo mice endophthalmitis models verify the biocompatibility and antibacterial function of the composite nanomaterials.


Asunto(s)
Sistemas de Liberación de Medicamentos , Endoftalmitis/tratamiento farmacológico , Imidazoles/química , Fotoquimioterapia , Zeolitas/química , Resinas Acrílicas/síntesis química , Resinas Acrílicas/química , Animales , Antibacterianos/farmacología , Supervivencia Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/ultraestructura , Humanos , Imidazoles/síntesis química , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Estructuras Metalorgánicas/química , Ratones , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Fármacos Fotosensibilizantes/farmacología , Polietilenglicoles/química , Conejos , Especies Reactivas de Oxígeno/metabolismo , Epitelio Pigmentado de la Retina/citología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/ultraestructura , Propiedades de Superficie , Vancomicina/farmacología , Zeolitas/síntesis química
5.
Macromol Rapid Commun ; 40(22): e1900435, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31596528

RESUMEN

Sequence-controlled polymerization is the forefront of polymer chemistry. Herein, the feasibility of sequence regulation by using organocatalyzed ring-opening polymerization (ROP) is demonstrated. In particular, ring expansion strategy is employed to synthesize pre-organized monomers 1 and 2. ROP is conducted by using 1,5,7-triazabicyclo[4.4.0]dec-5-ene and benzyl alcohol as the catalyst and initiator, respectively. Poly(ester amide)s (PEAs) P1-P3 comprising glycolic acid, lactic acid, and 7-aminoheptanoic acid units are obtained in high molecular weights and good yields. NMR and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry results verify the microstructural integrity of P1 and P2. Differential scanning calorimetry results show that PEA without methyl branches is crystalline. Moreover, thermal stability, surface wettability, and degradation profiles of P1-P3 are also investigated.


Asunto(s)
Amidas/química , Glicolatos/química , Ácido Láctico/química , Poliésteres/química , Polimerizacion , Amidas/síntesis química , Catálisis , Modelos Químicos , Estructura Molecular , Poliésteres/síntesis química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
6.
Macromol Rapid Commun ; 39(5)2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29250866

RESUMEN

A novel postpolymerization modification methodology is demonstrated to achieve selective functionalization of hyperbranched polymer (HBP). Terminal and internal acrylates of HBP derived from cross-metathesis polymerization (CMP) are functionalized in a chemoselective fashion using the thiol-Michael chemistries. Model reactions between different thiols (benzyl mercaptan and methyl thioglycolate) and acrylates (n-hexyl acrylate and ethyl trans-2-decenoate) by using dimethylphenylphosphine or amylamine as the catalyst are investigated to optimize the modification protocol for HBP. High-molecular-weight HBP P0 is generated through CMP of AB2 monomer 2, a compound containing one α-olefin and two acrylate metathetically polymerizable groups. CMP kinetics is monitored by NMR and gel permeation chromatography (GPC). Accordingly, microstructural analysis is conducted in detail, and CMP procedure is optimized. Postpolymerization modification of HBP P0 is performed via two distinguished strategies, namely one-step complete modification and sequential modification, to generate terminally and/or internally functionalized HBPs P1-P3 in a chemoselective fashion by using phosphine-initiated and/or base-catalyzed thiol-Michael chemistries. Finally, thermal stability and glass transition behaviors of HBPs P0-P3 are studied by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively.


Asunto(s)
Acrilatos/química , Poliésteres/química , Polimerizacion , Compuestos de Sulfhidrilo/química , Alquenos/química , Rastreo Diferencial de Calorimetría , Catálisis , Técnicas de Química Sintética , Modelos Químicos , Estructura Molecular , Poliésteres/síntesis química , Termogravimetría
7.
Macromol Rapid Commun ; 38(12)2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28370635

RESUMEN

Sequence-regulated polymerization is realized upon sequential cross-metathesis polymerization (CMP) and exhaustive hydrogenation to afford precision aliphatic polyesters with alternating sequences. This strategy is particularly suitable for the arrangement of well-known monomer units including glycolic acid, lactic acid, and caprolactic acid on polymer chain in a predetermined sequence. First of all, structurally asymmetric monomers bearing acrylate and α-olefin terminuses are generated in an efficient and straightforward fashion. Subsequently, cross-metathesis (co)polymerization of M1 and M2 using the Hoveyda-Grubbs second-generation catalyst (HG-II) furnishes P1-P3, respectively. Finally, hydrogenation yields the desired saturated polyesters HP1-HP3. It is noteworthy that the ε-caprolactone-derived unit is generated in situ rather than introduced to tailor-made monomers prior to CMP. NMR and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) results verify the microstructural periodicity of these precision polyesters. Differential scanning calorimetry (DSC) results reflect that polyesters without methyl side groups exhibit crystallinity, and unsaturated polyester samples show higher glass transition temperatures than their hydrogenated counterparts owing to structural rigidity.


Asunto(s)
Poliésteres/síntesis química , Polimerizacion , Rastreo Diferencial de Calorimetría , Caproatos , Lactonas , Poliésteres/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
8.
J Microencapsul ; 33(1): 43-52, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26626402

RESUMEN

CONTEXT: PLGA nanoparticles have been widely utilised to encapsulate lipophilic drugs for sustained release. OBJECTIVE: This study was to enhance encapsulation efficiency and drug loading for the poorly lipophilic drug dihydroartemisinin (DHA) in PLGA nanoparticles, where amphiphilic phospholipid was employed as the intermediate. MATERIALS AND METHODS: DHA-phospholipid complex formulation was optimised using the response surface method. DHA-phospholipid complex-nanoparticles (DHA-PLC-NPs) were prepared using the solvent evaporation method. RESULTS: The particle size, zeta potential, entrapment efficiency and drug loading of the nanoparticles were 265.3 ± 7.9 nm, -21.4 ± 6.3 mV, 74.2 ± 6.5% and 2.80 ± 0.35%, respectively. Compared with the rapidly released free form, DHA underwent sustained release from the nanoparticles. DHA-PLC-NPs presented stronger cell proliferative inhibition than DHA treatment alone and apoptosis was obviously induced after DHA-PLC-NPs treatment. CONCLUSION: Phospholipid complexes are useful intermediate to improve the lipophilicity of drugs, the interaction with the hydrophobic core of PLGA and the encapsulation efficiency of poorly lipophilic drugs in polymeric nanoparticles.


Asunto(s)
Artemisininas , Portadores de Fármacos , Ácido Láctico , Nanopartículas/química , Fosfolípidos , Ácido Poliglicólico , Artemisininas/química , Artemisininas/farmacocinética , Artemisininas/farmacología , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacología , Células Hep G2 , Humanos , Ácido Láctico/química , Ácido Láctico/farmacocinética , Ácido Láctico/farmacología , Nanopartículas/ultraestructura , Fosfolípidos/química , Fosfolípidos/farmacocinética , Fosfolípidos/farmacología , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacocinética , Ácido Poliglicólico/farmacología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico
9.
Anal Bioanal Chem ; 407(20): 6071-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26025552

RESUMEN

High-internal-phase-emulsion polymers (polyHIPEs) show great promise as solid-phase-extraction (SPE) materials because of the tremendous porosity and highly interconnected framework afforded by the high-internal-phase-emulsion (HIPE) technique. In this work, polyHIPE monolithic columns as novel SPE materials were prepared and applied to trace enrichment of cytokinins (CKs) from complex plant samples. The polyHIPE monoliths were synthesized via the in-situ polymerization of the continuous phase of a HIPE containing styrene (STY) and divinylbenzene (DVB) in a stainless column, and revealed highly efficient and selective enrichment ability for aromatic compounds. Under the optimized experimental conditions, a method using a monolithic polyHIPE column combined with liquid chromatography-electrospray tandem mass spectrometry (LC-MS-MS) was developed for the simultaneous extraction and sensitive determination of trans-zeatin (tZ), meta-topolin (mT), kinetin (K), and kinetin riboside (KR). The proposed method had good linearity, with correlation coefficients (R (2)) from 0.9957 to 0.9984, and low detection limits (LODs, S/N = 3) in the range 2.4-47 pg mL(-1) for the four CKs. The method was successfully applied to the determination of CKs in real plant samples, and obtained good recoveries ranging from 68.8 % to 103.0 % and relative standard deviations (RSDs) lower than 16 %.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Citocininas/análisis , Fabaceae/química , Nicotiana/química , Extracción en Fase Sólida/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Citocininas/aislamiento & purificación , Emulsiones/química , Límite de Detección , Hojas de la Planta/química , Polímeros/química , Estirenos/química , Espectrometría de Masas en Tándem/métodos , Compuestos de Vinilo/química
10.
Front Cell Infect Microbiol ; 14: 1352109, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38375360

RESUMEN

Background: Numerous studies have demonstrated the influence of gut microbiota on the development of obesity. In this study, we utilized Mendelian randomization (MR) analysis to investigate the gut microbiota characteristics among different types of obese patients, aiming to elucidate the underlying mechanisms and provide novel insights for obesity treatment. Methods: Two-sample multivariable Mendelian randomization (MR) analysis was employed to assess causal relationships between gut microbiota and various obesity subtypes. Gut microbiota data were obtained from the international consortium MiBioGen, and data on obese individuals were sourced from the Finnish National Biobank FinnGen. Eligible single-nucleotide polymorphisms (SNPs) were selected as instrumental variables. Various analytical methods, including inverse variance weighted (IVW), MR-Egger regression, weighted median, MR-RAPS, and Lasso regression, were applied. Sensitivity analyses for quality control included MR-Egger intercept tests, Cochran's Q tests, and leave-one-out analyses and others. Results: Mendelian randomization studies revealed distinct gut microbiota profiles among European populations with different obesity subtypes. Following multivariable MR analysis, we found that Ruminococcaceae UCG010 [Odds Ratio (OR): 0.842, 95% confidence interval (CI): 0.766-0.926, Adjusted P value: 0.028] independently reduced the risk of obesity induced by excessive calorie intake, while Butyricimonas [OR: 4.252, 95% CI: 2.177-8.307, Adjusted P value: 0.002] independently increased the risk of medication-induced obesity. For localized adiposity, Pasteurellaceae [OR: 0.213, 95% CI: 0.115-0.395, Adjusted P value: <0.001] acted as a protective factor. In the case of extreme obesity with alveolar hypoventilation, lactobacillus [OR: 0.724, 95% CI: 0.609-0.860, Adjusted P value: 0.035] reduced the risk of its occurrence. Additionally, six gut microbiota may have potential roles in the onset of different types of obesity. Specifically, the Ruminococcus torques group may increase the risk of its occurrence. Desulfovibrio and Catenabacterium may serve as protective factors in the onset of Drug-induced obesity. Oxalobacteraceae, Actinomycetaceae, and Ruminiclostridium 9, on the other hand, could potentially increase the risk of Drug-induced obesity. No evidence of heterogeneity or horizontal pleiotropy among SNPs was found in the above studies (all P values for Q test and MR-Egger intercept > 0.05). Conclusion: Gut microbiota abundance is causally related to obesity, with distinct gut microbiota profiles observed among different obesity subtypes. Four bacterial species, including Ruminococcaceae UCG010, Butyricimonas, Pasteurellaceae and lactobacillus independently influence the development of various types of obesity. Probiotic and prebiotic supplementation may represent a novel approach in future obesity management.


Asunto(s)
Actinomycetaceae , Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/genética , Obesidad/genética , Bacteroidetes , Clostridiales , Lactobacillus , Nonoxinol , Estudio de Asociación del Genoma Completo
11.
Water Res ; 250: 121078, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38159540

RESUMEN

Disinfection is vital in ensuring water safety. However, the traditional chlorine disinfection process is prone to producing toxic and harmful disinfection by-products (DBPs). The combination of quaternary ammonium polymer and the chlorine disinfection process can solve this shortcoming. Currently, research on the control of DBPs through the combined process is not systematic and the control effect between reducing the dosage of disinfectants and DBPs remains to be studied. Quaternized cyclodextrin polymers have attracted increasing attention due to their excellent adsorption and antibacterial properties, but their synergistic effect with chlorine disinfection is still unclear. In this study, a magnetic quaternized cyclodextrin polymer (MQCDP) is synthesized in an ionic liquid green system, and a combined process of MQCDP treatment and chlorine disinfection is established. The disinfection performance of the combined process on the actual water body along with its reducing effect on the amount of chlorine disinfectant as well as the trihalomethanes (THMs) and haloacetic acids (HAAs) DBPs are explored. MQCDP has a porous structure with a specific surface area of 825 m2 g-1 and is easily magnetically separated. MQCDP can remove most of the natural organic matter (UV254 absorbance decreased by 97 %) in the water at the dosage of 1 g L-1 and kill bacteria with a sterilization rate of 85 %. Compared with disinfection using chlorine alone, the combined process has higher disinfection efficiency and significantly reduces the amount of disinfectant used. A concentration of 5 mg/L of NaClO was needed to meet the standard by chlorine disinfectant alone, while only 2 mg/L of NaClO can meet the standard for the combined process, indicating 60 % of the chlorine demand was reduced. More importantly, the combined process can significantly reduce the generation potential of DBPs. When 10 mg/L of NaClO is added, the THMs and HAAs generated by the combined process decreased by 65 % and 34 %, respectively, compared with the levels produced by single chlorine disinfection. The combined process can reduce the dosage of chlorine disinfectant and MQCDP can adsorb humic acid DBP precursors in raw water, thus lowering the generation of DBPs during disinfection. In summary, MQCDP has excellent separation and antibacterial ability, and its synergistic effects combined with the chlorine disinfection process are of great significance for controlling the amount of disinfectant and the formation potential of DBPs, which has potential applications in actual water treatment.


Asunto(s)
Celulosa , Ciclodextrinas , Desinfectantes , Contaminantes Químicos del Agua , Purificación del Agua , Desinfección , Cloro/química , Desinfectantes/química , Cloruros/química , Halogenación , Trihalometanos/química , Antibacterianos/farmacología , Fenómenos Magnéticos , Contaminantes Químicos del Agua/análisis
12.
J Vis Exp ; (192)2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36847364

RESUMEN

The goal of this article is to present the application of a 24 G cannula and 3-0 polypropylene suture as a simple method for the exploration of the vas deferens. During the exploration of the vas deferens, a 24 G cannula needle was used to puncture it. The fluid in the smear confirmed the presence of sperm, to determine whether or not there was concomitant obstruction at the junction of the epididymis and the vas deferens. Then, a 3-0 polypropylene suture (this suture specification has the advantages of a smooth surface, robust quality, and can be passed through a 24 G cannula needle) was passed through the cannula needle to probe the location of the obstructed site. With this technique, exploration of the vas deferens could be more targeted and accurate.


Asunto(s)
Saltamontes , Yodo , Animales , Masculino , Conducto Deferente/cirugía , Polipropilenos , Cánula , Semen , Epidídimo , Suturas
13.
Adv Mater ; 35(28): e2301005, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37027814

RESUMEN

Dielectric elastomer actuators (DEAs) are widely exploited for actuating soft machines and granting soft robots with capability to operate in both underwater and on-land environments is important to make them adapt to more complex situations. Here, a DEA-driven, highly robust, amphibious imperceptible soft robot (AISR) based on an all-environment stable ionic conductive material is presented. A soft, self-healable, all-environment stable ionic conductor is developed by introducing cooperative ion-dipole interactions to provide underwater stability as well as efficient suppression of ion penetration. By tuning molecular structures of the material, a 50-time device lifetime increase compared with unmodified [EMI][TFSI]-based devices and excellent underwater actuating performance is achieved. With the synthesized ionic electrode, the DEA-driven soft robot exhibits amphibious functionality to traverse hydro-terrestrial regions. When encountering damage, the robot shows good resilience and can self-heal underwater and it also exhibits imperceptibility to light, sound, and heat.


Asunto(s)
Robótica , Elastómeros/química , Electrodos , Conductividad Eléctrica
14.
Chemosphere ; 341: 140056, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37696480

RESUMEN

Pillararene polymers have been widely used as excellent adsorbents for water treatment, but pillararene polymers with ultra-high specific surface area and versatility are still rarely reported. Herein, a quaternary ammonium salt modified pillar [5] arene polymer, QPBP [5], with specific surface area of 1844 m2 g-1 was successfully synthesized. Since QPBP [5] has abundant different adsorption sites, it exhibits excellent performance for the simultaneously removal of organic pollutants with different charges from water. The selected three model pollutants, Rhodamine B (RhB, positively charged), Sulfamethazine (SMT, electrically neutral) and Fulvic acid (FA, negatively charged), could be rapidly and efficiently removed from water by QPBP [5] within 10 min, which are much faster than them by most of the reported adsorbents. RhB and SMT are mainly adsorbed through hydrophobic interactions with the QPBP [5] surface, while FA is mainly removed through ion exchange. In addition, QPBP [5] also showed excellent reusability and adsorption performance for the environmentally relevant concentration of pollutants. Furthermore, the quaternary ammonium groups on QPBP [5] makes it a solid disinfectant with excellent antibacterial properties. In conclusion, QPBP [5] is a promising multifunctional adsorbent for the treatment of complex pollutants in water.


Asunto(s)
Desinfectantes , Contaminantes Ambientales , Purificación del Agua , Porosidad , Desinfectantes/farmacología , Polímeros
15.
Drug Dev Ind Pharm ; 38(8): 1008-14, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22126709

RESUMEN

OBJECTIVE: To design and optimize a drug-in-adhesive (DIA) type transdermal patch for tolterodine (TOL) based on acrylic and silicone matrixes. METHODS: Initial in vitro studies were conducted to optimize the formulations. Two types of adhesive matrixes, drug loading, and enhancers were evaluated on the TOL transport across rabbit skin. For in vivo studies, patches were administered to rabbit abdominal skin. Pharmacokinetic assessments were performed based on plasma level of TOL up to 28 h for acrylic patch and 52 h for silicone patch after topical application. RESULTS: The final formulation of acrylic adhesive type patch consisted of 10% TOL (w/w) and 5.8 × 10(-4) mol isopropyl myristate (IPM) and 2.9 × 10(-4) mol Span 80 in per unit gram (mol/g) of adhesive, while 2.5% TOL (w/w) and 2.9 × 10(-4) mol/g IPM for silicone adhesive type patch. Comparison of the pharmacokinetic parameters between two types of patches showed that the steady-state concentration of silicone type patch was 2-fold higher than that of acrylic type patch being 0.97 mg/L versus 0.49 mg/L, and the absolute bioavailability was 27.5% for silicone type patch and 6.3% for acrylic type patch, respectively. In addition, the prediction of in vivo drug level from the in vitro permeation data of silicone adhesive formulation was in good agreement with actual observed concentration data in rabbits. CONCLUSION: These results indicate that the silicone type of TOL patch is an appropriate delivery system for the treatment of overactive bladder (OAB).


Asunto(s)
Adhesivos/administración & dosificación , Adhesivos/química , Compuestos de Bencidrilo/administración & dosificación , Compuestos de Bencidrilo/química , Cresoles/administración & dosificación , Cresoles/química , Fenilpropanolamina/administración & dosificación , Fenilpropanolamina/química , Siliconas/administración & dosificación , Siliconas/química , Adhesivos/farmacocinética , Administración Cutánea , Animales , Compuestos de Bencidrilo/farmacocinética , Disponibilidad Biológica , Química Farmacéutica/métodos , Cresoles/farmacocinética , Sistemas de Liberación de Medicamentos/métodos , Masculino , Miristatos/química , Fenilpropanolamina/farmacocinética , Conejos , Siliconas/farmacocinética , Piel/metabolismo , Absorción Cutánea/efectos de los fármacos , Tartrato de Tolterodina , Parche Transdérmico , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Vejiga Urinaria Hiperactiva/metabolismo
16.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 37(11): 1171-6, 2012 Nov.
Artículo en Zh | MEDLINE | ID: mdl-23202627

RESUMEN

OBJECTIVE: To explore the changes and clinical significance of saliva urea, creatinine (Cr), uric acid (UA) in both healthy people and chronic kidney disease (CKD) patients, and to provide a noninvasive, quick, accurate and reliable test to diagnose kindey disease. METHODS: Urea, Cr and UA in the saliva and serum collected from both healthy people and the CKD patients were measured by biochemical analyzer. We calculated the correlation coefficient of Urea, Cr and UA between the saliva and serum, compared the levels of saliva Urea, Cr and UA among CKD patients in different periods, drew the receiver operation characteristic (ROC) curve and analyzed the sensitivity and specificity of saliva Urea, Cr and UA to predict CKD patients in various periods. RESULTS: The concentrations of Urea, Cr and UA in both the saliva and the serum were positively correlated in healthy individuals and CKD patients (r = 0.918, 0.932, 0.840 and 0.984, 0.971, 0.920). The levels of saliva Urea, Cr and UA in the CKD patients were significantly higher than those of healthy people (P<0.05). Saliva Urea, Cr and UA concentrations of middle and late stage CKD patients were obviously higher than those of healthy people and early stage CKD patients (P<0.05). Areas under the curve (AUC) of the ROC of Urea, Cr and UA to diagnose diverse periods of CKD were 0.898, 0.897 and 0.848. The sensitivity was 0.806, 0.776 and 0.704; and the specificity was 0.968, 0.989 and 0.871. CONCLUSION: The levels of Urea, Cr and UA between the saliva and the serum are closely related. The concentration of saliva Urea, Cr and UA can reflect the renal damage, monitor kidney function of the CKD patients, and help diagnose middle to late stage CKD patients. It is a simple, nonivasive and quick method.


Asunto(s)
Creatinina/análisis , Insuficiencia Renal Crónica/metabolismo , Saliva/química , Urea/análisis , Ácido Úrico/análisis , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
17.
Lab Chip ; 22(21): 4224-4237, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36178361

RESUMEN

Next-generation sequencing (NGS) is an essential technology for DNA identification in genomic research. DNA fragmentation is a critical step for NGS and doing this on-chip is of great interest for future integrated genomic solutions. Here we demonstrate fast acoustofluidic DNA fragmentation via ultrasound-actuated elastic polydimethylsiloxane (PDMS) microstructures that induce acoustic streaming and associated shear forces when placed in the field of an ultrasonic transducer. Indeed, acoustic streaming locally generates high tensile stresses that can mechanically stretch and break DNA molecule chains. The improvement in efficiency of the on-chip DNA fragmentation is due to the synergistic effect of these tensile stresses and ultrasonic cavitation phenomena. We tested these microstructure-induced effects in a DNA-containing microfluidic channel both experimentally and by simulation. The DNA fragmentation process was evaluated by measuring the change in the DNA fragment size over time. The chip works well with both long and short DNA chains; in particular, purified lambda (λ) DNA was cut from 48.5 kbp to 3 kbp in one minute with selected microstructures and further down to 300 bp within two and a half minutes. The fragment size of mouse genomic DNA was reduced from 1.4 kbp to 400 bp in one minute and then to 200 bp in two and a half minutes. The DNA fragmentation efficiency of the chip equipped with the PDMS microstructures was twice that of the chip without the microstructures. Exhaustive comparison shows that the on-chip fragmentation performance reaches the level of high-end professional standards. Recently, DNA fragmentation was shown to be enhanced using vibrating air microbubbles when the chip was placed in an acoustic field. We think the microbubble-free microstructure-based device we present is easier to operate and more reliable, as it avoids microbubble preparation and maintenance, while showing high DNA fragmentation performance.


Asunto(s)
Microfluídica , Ultrasonido , Ratones , Animales , Fragmentación del ADN , Dimetilpolisiloxanos/química , Acústica , ADN/genética
18.
Sci Total Environ ; 806(Pt 4): 150739, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34619202

RESUMEN

Chlorophenols (CPs) have been listed as priority control pollutants because of their high toxicity and wide range. An In-situ monitoring technique using diffusive gradients in thin films based on porous ß-cyclodextrin polymers as binding materials (CDP-DGT), was established to monitor four typical CPs, namely, 4-Chlorophenol (4-CP), 2,4-Dichlorophenol (2,4-DCP), 2,4,5-Trichlorophenol (2,4,5-TCP), 2,4,6-Trichlorophenol (2,4,6-TCP) in water and soils. The performance of CDP-DGT are stable under the conditions of pH 3.5-9.3, ionic strength 0.001-0.500 mol L-1 and dissolved organic matter concentration 0-20 mol L-1. The adsorption capacities of CDP-DGT for 4-CP, 2,4-DCP, 2,4,5-TCP, 2,4,6-TCP were 57.80 µg cm-2, 98.82 µg cm-2, 95.69 µg cm-2 and 98.91 µg cm-2, respectively. The time-average weighted concentrations of four CPs determined by CDP-DGT at Sanjiangkou wharf (Yangtze river, China) were consistent with the results of grab sampling, indicating the feasibility of CDP-DGT application in actual water. In addition, the distribution of CPs in the red soil of Kunming and paddy soil of Yixing were also studied by CDP-DGT, and the desorption kinetics in the two soils were analyzed with the DIFS model. The higher the soil organic matter content is, the more CPs are distributed in the soil solid phase. CPs in both soils can be partially resupplied to soil solution from the soil solid phase and the higher the partition coefficient for labile CPs is, the stronger the supplement capacity is.


Asunto(s)
Clorofenoles , Contaminantes Químicos del Agua , beta-Ciclodextrinas , Difusión , Monitoreo del Ambiente , Polímeros , Suelo , Agua , Contaminantes Químicos del Agua/análisis
19.
Mar Pollut Bull ; 180: 113809, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35688065

RESUMEN

This study was carried out in Luoyuan Bay in March 2021. The species composition of microalgae community colonizing on microplastics called epimicroplastic microalgae (EMP-MA) was analyzed and compared with planktonic microalgae (PM) community. The species number of EMP-MA community (73) was higher than that of PM community (56). However Simpson Index and Pielou Evenness Index of EMP-MA community were significantly lower than that of PM community (P < 0.05). Although diatom was the most diverse and abundant taxa in both EMP-MA and PM community, their species compositions were significantly different (P < 0.05). Dominant species were also different between the two communities. Moreover, 12 harmful algal species were found in EMP-MA community, which may drift with microplastics and increase the risks of harmful algal blooms (HABs). This study is helpful to reveal the dispersal mechanism of HABs and potential impacts of EMP-MA on marine ecosystem.


Asunto(s)
Microalgas , Microplásticos , Bahías , China , Ecosistema , Floraciones de Algas Nocivas , Plancton , Plásticos
20.
Water Res ; 222: 118917, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35961197

RESUMEN

Keeping water clean is of vital significance for human health and environmental protection. In order to remove organic micro-pollutants and natural organic substances in water bodies and kill pathogenic microorganisms simultaneously, this study synthesized a multifunctional porous ß-cyclodextrin polymer with a high specific surface area by introducing quaternary ammonium groups and rigid benzene rings, respectively, which was then polymerized with crosslinking agent-4,4'-bis (chloromethyl)-1,1'-biphenyl (BCMBP) in an ionic liquid system. The grafting of quaternary ammonium groups was beneficial for the removal of negative-charged humic acid (HA) and sterilization. The introduction of numerous rigid structures during benzylation and Friedel-Crafts alkylation reaction could significantly improve the porosity and specific surface area of the polymer, conducive to the exposure of cyclodextrin binding sites and contaminant adsorption. By changing the proportions of quaternization and benzylation, the structure and surface properties of the polymer could be adjusted, thus further regulating the adsorption performance. Compared with activated carbon, the polymer named BQCD-BP with a huge surface area of 1133 m2 g-1 prepared under optimized conditions showed outstanding adsorption performance and sterilization ability. The pseudo-second-order kinetic constant of BQCD-BP reached 1.2058 g·mg-1·min-1, which was approximately 50 times greater than that of activated carbon (0.0256 g·mg-1·min-1) under the same experimental condition. The adsorption capacity of BQCD-BP to HA was twice as high as that to AC, and the antibacterial ability of BQCD-BP was significant, achieving 90% at the dosage of 1g L-1. Moreover, the adsorption process was hardly affected by the hydrochemical conditions, and the polymer was easy to regenerate. In addition, the excellent adsorption and antibacterial performance of the polymer were also identified by natural water treatment. COD was almost completely removed, and the removal efficiency of TP reached 92% after contact with BQCD-BP. The sterilization rate of BQCD-BP to viable bacteria in complex water bodies reached 82%. Undoubtedly, BQCD-BP is a potential multifunctional water treatment material with reasonable design in the actual water purification.


Asunto(s)
Compuestos de Amonio , Ciclodextrinas , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Antibacterianos , Celulosa , Carbón Orgánico/química , Ciclodextrinas/química , Humanos , Sustancias Húmicas , Polímeros/química , Porosidad , Contaminantes Químicos del Agua/química
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