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1.
Langmuir ; 40(23): 11966-11973, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38809418

RESUMEN

In printing, microreactors, and bioassays, the precise control of micrometer-scale droplet generation is essential but challenging, often restricted by the equipment and nozzles used in traditional methods. We introduce a needle-plate electrode corona discharge technique that injects charges into an oil layer, enabling the precise manipulation of droplet polarization and splitting. This method allows for meticulous adjustment of microdroplet formation regarding location, size, and quantity by modulating the discharge voltage, discharge time, and electrode positioning. It enables the immediate initiation and cessation of droplet production, thereby facilitating on-demand droplet generation. Our study on the voltage-dependent droplet stretch coefficient shows that as the voltage increases, the droplets transition from controlled splitting to regular Taylor cone-like ejections, eventually reaching the Rayleigh limit and fully breaking apart. These advancements significantly improve microfluidic droplet manipulation, offering considerable benefits for applications in targeted drug delivery, rapid disease diagnostics, and precise environmental monitoring.

2.
Molecules ; 29(4)2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38398666

RESUMEN

Although nano SiO2 exhibits excellent application potential in the field of oil and gas exploration and development, such as drilling fluid, enhanced oil/gas recovery, etc., it is prone to agglomeration and loses its effectiveness due to the action of cations in saline environments of oil and gas reservoirs. Therefore, it is crucial to study the mechanism of the change in energy between nano SiO2 and cations for its industrial application. In this paper, the effect of cations (Na+, K+, Ca2+, and Mg2+) on the surface energy of nano SiO2 particles is investigated from the perspective of molecular motion and electronic change by density functional theory. The results are as follows: Due to the electrostatic interactions, cations can migrate towards the surface of nano SiO2 particles. During the migration process, monovalent cations are almost unaffected by water molecules, and they can be directly adsorbed on the surface by nano SiO2 particles. However, when divalent cations migrate from a distance to the surface of nano SiO2 particles, they can combine with water molecules to create an energy barrier, which can prevent them from moving forward. When divalent cations break through the energy barrier, the electronic kinetic energy between them and nano SiO2 particles changes more strongly, and the electrons carried by them are more likely to break through the edge of the atomic nucleus and undergo charge exchange with nano SiO2 particles. The change in interaction energy is more intense, which can further disrupt the configuration stability of nano SiO2. The interaction energy between cations and nano SiO2 particles mainly comes from electrostatic energy, followed by Van der Waals energy. From the degree of influence of four cations on nano SiO2 particles, the order from small to large is as follows: K+ < Na+ < Mg2+ < Ca2+. The research results can provide a theoretical understanding of the interaction between nano SiO2 particles and cations during the application of nano SiO2 in the field of oil and gas exploration and development.

3.
Environ Sci Technol ; 57(32): 12094-12104, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37490389

RESUMEN

In this study, Ru(III) ions were utilized to activate periodate (PI) for oxidation of trace organic pollutants (TOPs, e.g., carbamazepine (CBZ)). The Ru(III)/PI system can significantly promote the oxidation of CBZ in a wide initial pH range (3.0-11.0) at 1 µM Ru(III), showing much higher performance than transition metal ions (i.e., Fe(II), Co(II), Zn(II), Fe(III), Cu(II), Ni(II), Mn(II), and Ce(III)) and noble metal ion (i.e., Ag(I), Pd(II), Pt(II), and Ir(III)) activated PI systems. Probe experiments, UV-vis spectra, and X-ray absorption near-edge structure (XANES) spectra confirmed high-valent Ru-oxo species (Ru(V)=O) as the dominant oxidant in the process. Because of the dominant role of Ru(V)=O, the Ru(III)/PI process exhibited a remarkable selectivity and strong anti-interference in the oxidation of TOPs in complex water matrices. The Ru(V)=O species can undertake 1-e- and 2-e- transfer reactions via the catalytic cycles of Ru(V)=O → Ru(IV) → Ru(III) and Ru(V)=O → Ru(III), respectively. The utilization efficiency of PI in the Ru(III)/PI process for the oxidation of TOPs can approach 100% under optimal conditions. PI stoichiometrically transformed into IO3- without production of undesired iodine species (e.g., HOI and I2). This study developed an efficient and environmentally benign advanced oxidation process for rapid removal of TOPs and enriched understandings on reactivity of Ru(V)=O and Ru catalytic cycles.


Asunto(s)
Contaminantes Ambientales , Compuestos Férricos , Metales , Oxidación-Reducción , Agua/química
4.
Sensors (Basel) ; 23(22)2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-38005680

RESUMEN

In the case of strong background noise, a tri-stable stochastic resonance model has higher noise utilization than a bi-stable stochastic resonance (BSR) model for weak signal detection. However, the problem of severe system parameter coupling in a conventional tri-stable stochastic resonance model leads to difficulty in potential function regulation. In this paper, a new compound tri-stable stochastic resonance (CTSR) model is proposed to address this problem by combining a Gaussian Potential model and the mixed bi-stable model. The weak magnetic anomaly signal detection system consists of the CTSR system and judgment system based on statistical analysis. The system parameters are adjusted by using a quantum genetic algorithm (QGA) to optimize the output signal-to-noise ratio (SNR). The experimental results show that the CTSR system performs better than the traditional tri-stable stochastic resonance (TTSR) system and BSR system. When the input SNR is -8 dB, the detection probability of the CTSR system approaches 80%. Moreover, this detection system not only detects the magnetic anomaly signal but also retains information on the relative motion (heading) of the ferromagnetic target and the magnetic detection device.

5.
Nano Lett ; 22(8): 3385-3391, 2022 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-35436130

RESUMEN

Surfactant-dictated syntheses of nanomaterials with well-defined shapes offer an extra dimension of control beyond nanoparticle size and chemical composition on the properties and self-assembly behaviors of colloidal materials. However, the surfactant bilayers on nanocrystals often cause great difficulty toward DNA grafting due to their unfavorable electrostatic charges and dense surface packing. Herein a revisit to this dilemma unveils a rapid charge inversion and enhanced colloidal/chemical stabilities of cationic-bilayer-covered nanocrystals upon DNA adsorption. Decoupling this hidden scenario provides a rationale to significantly improve DNA functionalization of surfactant-capped nanocrystals. Accordingly, fully tunable DNA conjugation (via Au-S bonding) on up to seven classes of surfactant-coated metal nanounits is easily and consistently achievable. The DNA-nanocrystal complexes featuring a continuously variable DNA density function well in DNA-guided nanoassembly. Our method opens the door to a wealth of material building blocks derived by surfactant-directed nanosyntheses toward DNA-programmable, extremely diversified, and highly complicated structures and functions.


Asunto(s)
Nanopartículas , Nanoestructuras , ADN/química , Electricidad Estática , Tensoactivos
6.
Molecules ; 28(18)2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37764408

RESUMEN

A series of vinyl versatate (VV10) modified poly(vinyl acetate) adhesive (HVPVAc) were prepared using soap-free emulsion polymerization. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy was used to characterize the structure of the modified poly(vinyl acetate) latex. The effect of the VV10 content on particle size, viscosity, mechanical properties, and T-peel strength of the modified poly(vinyl acetate) was determined. No absorption peak at 1675-1500 cm-1 in the ATR-FTIR spectrum was observed as a result of the carbon-carbon double bond reacting completely. With the occurrence of -C-O-C and the disappearance of the carbon-carbon double bond in the FTIR spectrum, a more complex structure formed. The structure improves the mechanical properties. Increasing the VV10 content resulted in an increase in particle size from 63 nm to 221 nm, a steady increase in the viscosity of the HVPVAc latex, an increase in tensile strength from 7 MPa to 13.4 MPa, and a decrease in breaking elongation from 1310% to 1004%. As the VV10 content increased from 0 to 30% by weight, the T-peel strength of the HVPVAc adhesive increased from 8.35 N/mm to 18.97 N/mm, indicating improved adhesive performance.

7.
Water Sci Technol ; 88(7): 1863-1874, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37831001

RESUMEN

In this work, the formation of carbon-based nanomaterials-fulvic acid (CNMs-FA) composites and their capacities for the adsorption and photodegradation of typical organic contaminants in aqueous solutions were investigated. The results suggested that the formation of CNMs-FA composites was dominated by adsorbing FA on CNMs via the physisorption process, which fit the pseudo-first-order kinetic model and the Langmuir isotherm model. The formed CNMs-FA composites were characterized by using the Brunauer-Emmett-Teller, scanning electron microscopy, and infrared spectroscopy techniques and further applied for examining their effects on the adsorption and photodegradation of selected organic contaminants in aqueous solutions. The adsorption of organic contaminants on CNMs-FA composites is mainly involved in hydrogen bonding and electrostatic interactions between organic contaminants and FA species adhering to CNMs. In addition, the CNMs-FA composites are able to promote the photosensitive degradation of organic contaminants due to the photogenerated reactive species including ROS and CNMs-3FA* under sunlight irradiation. This study provided a deeper and more comprehensive understanding of the environmental behavior of CNMs in real natural surface water and clarified the underlying mechanisms.


Asunto(s)
Nanoestructuras , Contaminantes Químicos del Agua , Carbono , Adsorción , Fotólisis , Agua , Cinética , Contaminantes Químicos del Agua/química
8.
BMC Nephrol ; 23(1): 417, 2022 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-36585621

RESUMEN

BACKGROUND: To investigate depression and anxiety and related factors among patients receiving maintenance hemodialysis (MHD). METHODS: This cross-sectional study included patients underwent MHD in 3/2022 at Jinshan Hospital affiliated to Fudan University. Depression and anxiety levels of patients were assessed using Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI), respectively. SF-36 was used to assess patients' quality of life. Multiple linear regression analysis was used to determine the variables associated with the scores of BDI/BAI. RESULTS: A total of 103 patients were included, 71 cases (68.93%) and 38 cases (36.89%) with depression and anxiety, respectively. The scores of almost all domains of the SF-36 showed a declining trend with increasing depression or anxiety among patients on MHD. Higher Charlson Comorbidity Index (CCI) (ß =0.066, 95%CI: 0.016-0.116, P = 0.010), lower educational status (ß = - 0.139, 95%CI: - 0.243- -0.036, P = 0.009), and number of oral medications (ß =0.177, 95%CI: 0.031-0.324, P = 0.018) were significantly associated with higher BDI scores. Longer dialysis duration (ß =0.098, 95%CI: 0.003-0.193, P = 0.044) and number of oral medications (ß =4.714, 95%CI: 1.837-7.590, P = 0.002) were significantly associated with higher BAI scores. CONCLUSIONS: Depression and anxiety may be likely to occur among patients undergoing MHD and impact their quality of life. Higher CCI, lower educational status and usage of multiple oral medications may be associated with depression, whereas longer dialysis duration and multiple oral medications may be associated with anxiety in MHD patients.


Asunto(s)
Depresión , Diálisis Renal , Humanos , Diálisis Renal/efectos adversos , Depresión/epidemiología , Estudios Transversales , Calidad de Vida , Ansiedad/epidemiología
9.
J Am Chem Soc ; 143(2): 868-878, 2021 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-33417765

RESUMEN

Organelle-targeted activatable photosensitizers are attractive to improve the specificity and controllability of photodynamic therapy (PDT), however, they suffer from a big problem in the photoactivity under both normoxia and hypoxia due to the limited diversity of phototoxic species (mainly reactive oxygen species). Herein, by effectively photocaging a π-conjugated donor-acceptor (D-A) structure with an N-nitrosamine substituent, we established a unimolecular glutathione and light coactivatable photosensitizer, which achieved its high performance PDT effect by targeting mitochondria through both type I and type II (dual type) reactions as well as secondary radicals-participating reactions. Of peculiar interest, hydrogen radical (H•) was detected by electron spin resonance technique. The generation pathway of H• via reduction of proton and its role in type I reaction were discussed. We demonstrated that the synergistic effect of multiple reactive species originated from tandem cascade reactions comprising reduction of O2 by H• to form O2•-/HO2• and downstream reaction of O2•- with •NO to yield ONOO-. With a relatively large two-photon absorption cross section for photoexcitation in the near-infrared region (166 ± 22 GM at 800 nm) and fluorogenic property, the new photosensitizing system is very promising for broad biomedical applications, particularly low-light dose PDT, in both normoxic and hypoxic environments.


Asunto(s)
Hidrógeno/metabolismo , Óxido Nítrico/antagonistas & inhibidores , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Radicales Libres/antagonistas & inhibidores , Radicales Libres/metabolismo , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Estructura Molecular , Óxido Nítrico/metabolismo , Fármacos Fotosensibilizantes/química
10.
Environ Sci Technol ; 55(13): 8937-8946, 2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34165279

RESUMEN

Chlorine is commonly used in disinfection processes in wastewater treatment plants prior to discharge of the effluents into receiving waters. Effluent organic matter and humic substances constitute up to 90% of dissolved organic matter (DOM) in receiving water, which induces photogeneration of reactive species (RS) such as excited triplet state of DOM (3DOM*), singlet oxygen (1O2), and hydroxyl radical (•OH). The RS plays an important role in the attenuation of trace pollutants. However, the effect of chlorine disinfection on the photoreactivity of the DOM has remained unclear. Here, we investigated the physicochemical properties and subsequent RS variation after chlorination of DOM. Solid-state 13C cross-polarization/magic angle-spinning NMR and Fourier transform ion cyclotron resonance mass spectrometry verified that the aromaticity, electron-donating capacity (EDC), and average molecular weight of DOM decreased markedly after chlorination. It was found for the first time that the photoproduction of 3DOM*, 1O2, and •OH increased markedly after chlorination of DOM upon irradiation of simulated sunlight. The quantum yields of 3DOM*, 1O2, and •OH were positively correlated with E2/E3 (ratio of the absorbance at 254 to 365 nm) while negatively correlated with EDC before and after chlorination. These findings highlight the synergetic effect of chlorine disinfection on the photosensitization of DOM under irradiation of sunlight, which will promote the removal of trace pollutants in surface waters.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Cloro , Desinfección , Halogenación , Sustancias Húmicas/análisis
11.
J Environ Sci (China) ; 106: 47-65, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34210439

RESUMEN

A field campaign was conducted to study the PM2.5 and atmospheric gases and aerosol's components to evaluate the efficacy of radical measures implemented by the Chinese government to improve air quality during the 2016 G20 Summit in Hangzhou China. The lower level of PM2.5 (32.48 ± 11.03 µg/m3) observed during the control period compared to pre-control and post-control periods showed that PM2.5 was alleviated by control policies. Based on the mass concentrations of particulate components, the emissions of PM2.5 from local sources including fossil fuel, coal combustion, industry and construction were effectively reduced, but non-exhaust emission was not reduced as effectively as expected. The accumulation of SNA (SO42-, NO3-, NH4+) was observed during the control period, due to the favourable synoptic weather conditions for photochemical reactions and heterogeneous hydrolysis. Because of transboundary transport during the control period, air masses from remote areas contributed significantly to local PM2.5. Although, secondary organic carbon (OCsec) exhibited more sensitivity than primary organic carbon (OCpri) to control measures, and the increased nitrogen oxidation ratio (NOR) implied the regional transport of aged secondary aerosols to the study area. Overall, the results from various approaches revealed that local pollution sources were kept under control, indicating that the implementation of mitigation measures were helpful in improving the air quality of Hangzhou during G20 summit. To reduce ambient levels of PM2.5 further in Hangzhou, regional control policies may have to be taken so as to reduce the impact of long-range transport of air masses from inland China.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Contaminación del Aire/prevención & control , China , Monitoreo del Ambiente , Material Particulado/análisis , Estaciones del Año , Emisiones de Vehículos/análisis
12.
Neurosurg Rev ; 43(1): 231-239, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30327895

RESUMEN

Intraosseous cavernous malformations (ICMs) of the skull are relatively rare, benign, and slow-growing tumors. Knowledge of these lesions is poor. The goals of this study were to describe the clinical manifestations, radiological features, and long-term surgical outcomes of this disease. We performed a retrospective analysis of a series of 16 cranial ICM patients who underwent surgical treatment in our hospital between 2003 and 2016. The incidence of cranial ICM was 1.15% among the entire series of intracranial and intraspinal CMs. Our cohort included 6 male and 10 female patients; their mean age at operation was 38.7 years (range, 1.9 to 63 years). Slowly growing swelling was the commonest clinical manifestation of this disease. Complete lesion resection was achieved in all but one patient, and cranioplasty was performed using titanium mesh in 11 cases. Postoperative complication was found in one patient who developed diplopia, and this symptom resolved spontaneously before discharge. The mean follow-up period after operation was 76.2 months (range, 19 to 119 months). Only the patient with petroclival ICM had some occasional headaches (mRS = 1); others were all in stable neurological status (mRS = 0). No lesion recurrence was found during the follow-up period. Although cranial ICM is rare, it should always be considered as a differential diagnosis in the case of firm, gradually enlarging skull lesions. Surgical resection should be the treatment of choice for the symptomatic patients and their long-term outcomes were excellent after gross total removal.


Asunto(s)
Hemangioma Cavernoso del Sistema Nervioso Central/diagnóstico , Hemangioma Cavernoso del Sistema Nervioso Central/cirugía , Complicaciones Posoperatorias/epidemiología , Neoplasias Craneales/diagnóstico , Neoplasias Craneales/cirugía , Adolescente , Adulto , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Cefalea/etiología , Hemangioma Cavernoso del Sistema Nervioso Central/epidemiología , Humanos , Incidencia , Lactante , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Estudios Retrospectivos , Neoplasias Craneales/epidemiología , Resultado del Tratamiento , Adulto Joven
13.
Neurosurg Rev ; 43(2): 597-608, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30771118

RESUMEN

This retrospective study explored the risk factors for the occurrence of seizures in the pre- and postoperative period in patients undergoing supratentorial meningiomas surgery to investigate those who are likely to benefit from prophylactic antiepileptic drugs (AEDs). We reviewed the medical records of 778 supratentorial meningiomas patients who were operated at our institution between 2011 and 2012. A total of 100 (12.9%) patients experienced preoperative seizures; 41 patients (5.3%) experienced postoperative in-hospital seizures, and 91 (13.5%, n = 673) patients experienced postoperative seizures after discharge. Multivariate analysis revealed that motor cortex involvement (odds ratio [OR] 3.243, P < 0.001) and peritumoral edema ≥ 1 cm (OR 3.936, P < 0.001) were significant risk factors of preoperative seizures. Whereas presenting with headache (OR 0.259, P < 0.001) and age ≥ 55 years at surgery (OR 0.514, P = 0.009) showed decreased incidence of preoperative seizures. The involvement of motor cortex (OR 3.290, P = 0.003), postoperative Karnofsky Performance Scale (KPS) ≤ 70 (OR 5.389, P < 0.001), preoperative seizure (OR 4.003, P < 0.001), and occurrence of any medical/surgical complication (OR 3.925, P = 0.001) were significant risk factors for postoperative in-hospital seizures. Postoperative seizures after discharge were associated with tumor maximal diameter ≥ 3.5 cm (OR 1.903, P = 0.022), preoperative seizures (OR 4.350, P < 0.001), postoperative in-hospital seizures (OR 6.385, P < 0.001), and tumor recurrence/progression (OR 7.642, P < 0.001). The probability of seizure freedom in the 5-year follow-up was roughly 59% among patients with preoperative seizures, and 87% among patients without preoperative seizures. Cox regression analysis showed that tumor recurrence/progression (relative risk 2.987, 95% CI 1.517, 5.879, P = 0.002) was the only predictor of postoperative seizures in patients without a history of preoperative epilepsy. The use of postoperative prophylactic antiepileptic drug (AED) did not reduce the incidence of seizures in our analysis. Understanding the risk factors for seizures might help clinicians to predict their occurrence and develop effective anti-epileptic treatment strategies. Further prospective randomized controlled trials are needed to determine the risk factors for seizures and the efficacy of AED prophylaxis.


Asunto(s)
Meningioma/complicaciones , Meningioma/cirugía , Complicaciones Posoperatorias/epidemiología , Convulsiones/epidemiología , Convulsiones/etiología , Neoplasias Supratentoriales/complicaciones , Neoplasias Supratentoriales/cirugía , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Anticonvulsivantes/uso terapéutico , Pueblo Asiatico , Edema Encefálico/complicaciones , Edema Encefálico/epidemiología , Niño , China/epidemiología , Femenino , Cefalea/complicaciones , Cefalea/epidemiología , Humanos , Incidencia , Estado de Ejecución de Karnofsky , Masculino , Persona de Mediana Edad , Corteza Motora/patología , Corteza Motora/cirugía , Factores de Riesgo , Convulsiones/prevención & control , Resultado del Tratamiento , Adulto Joven
14.
Org Biomol Chem ; 17(34): 8001-8007, 2019 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-31410437

RESUMEN

A novel photosensitizer BDPI-lyso has been developed for photodynamic therapy (PDT). The photosensitizer BDPI-lyso showed a high singlet oxygen quantum yield (ΦΔ = 0.95) and low fluorescence quantum yield (ΦF = 0.05) in EtOH. Different singlet oxygen quantum yields were found in acidic solution (pH = 5, ΦΔ = 0.51) and in neutral solution (pH = 7, ΦΔ = 0.38). DFT and TD-DFT calculations of BDPI-lyso and its protonated product BDPI-lysoH+ indicated that the S1/T3 transition was responsible for the intersystem crossing (ISC) enhancement which would promote the production of singlet oxygen. The negligible dark cytotoxicity toward the hepatoma cell line Bel-7402 was confirmed by MTT assay, AO/EB dual staining, and cell images. Upon exposure to a low dose of light illumination, the disruption of the cell plasma membrane and the calculated half-maximal inhibitory concentration (IC50) of 0.4 µM showed a high phototoxicity of the photosensitizer BDPI-lyso. The light-induced intracellular ROS generation was verified as the PDT mechanism of BDPI-lyso. Colocalization experiments of LysoTracker Green and BDPI-lyso in the dark indicated the good lysosome-targeting ability of BDPI-lyso. The images of cells costained with LysoTracker Green and BDPI-lyso, and the appearance of intracellular and extracellular blebs with green fluorescence after light illumination revealed the light-induced dysfunction of lysosomes and cell apoptosis.


Asunto(s)
Compuestos de Boro/farmacología , Lisosomas/efectos de los fármacos , Fármacos Fotosensibilizantes/farmacología , Oxígeno Singlete/química , Apoptosis/efectos de los fármacos , Compuestos de Boro/efectos de la radiación , Línea Celular Tumoral , Teoría Funcional de la Densidad , Humanos , Concentración de Iones de Hidrógeno , Luz , Modelos Químicos , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismo
15.
J Sep Sci ; 42(6): 1248-1256, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30641617

RESUMEN

Graphene oxide based molecularly imprinted polymers modified with ß-cyclodextrin were prepared as solid-phase extraction column sorbents for specific recognition and sensitive detection of di(2-ethylhexyl) phthalate in water samples. The morphology and composition of synthesized sorbents were characterized by scanning electron microscopy, thermo-gravimetric analysis, Raman spectroscopy, and Fourier-transform infrared spectroscopy. The conditions affecting the performance of extraction procedures such as desorption solvent types and volume, sample pH and volume were investigated. The loading capacity (8.2 µg/mg) of the prepared sorbents increased eight times after modification with ß-cyclodextrin. The developed extraction procedures coupled to high-performance liquid chromatography exhibited good linearity (0.2-500 µg/L), low limit of detection (0.052 µg/L), and good precision (relative standard deviation˂5.7%) under optimized conditions. The developed solid-phase extraction technique with prepared sorbents has been successfully applied in extracting trace di(2-ethylhexyl) phthalate from real natural waters with high efficiency, good selectivity, and desirable recoveries.

16.
Soft Matter ; 15(1): 30-37, 2018 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-30462132

RESUMEN

Tunable and reversible dry adhesion has attracted much attention in academia and industry due to its wide applications ranging from releasable joints to stamps for transfer printing. Here, a simple yet robust magnetically actuated, aphid-inspired design of an elastomeric surface that provides rapidly tunable and highly reversible adhesion strength is reported. The magnetically actuated adhesive features open reservoirs filled with magnetic particles and encapsulated by a thin surface membrane, which can be deformed in a controlled manner via the magnetic field, thus, to tune the adhesion. The combination of the rate dependent effect and magnetic actuation of the thin surface membrane offers continuously tunable adhesion with a great switchability and a quick response. Experimental and theoretical studies reveal the underlying physics and provide design guidelines to optimize geometries for the broad control of adhesion. Demonstrations of this concept in stamps for transfer printing of silicon wafers in air and in a vacuum with a selective and programmable mode illustrate the capabilities for deterministic assembly and the potential in the semiconductor industry.

17.
Int J Med Sci ; 15(11): 1118-1128, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30123049

RESUMEN

Long-term administration of classic immunosuppressants can induce severe adverse effects. The development of novel immunosuppressants confronts great challenges and opportunities. Ibrutinib, an approved drug for B-cell lineages and chronic graft versus host disease (cGVHD), exhibits immunosuppressive efficacy in autoimmune diseases. Ibrutinib's potential as an immunosuppressant in organ transplantation has not been investigated to date. In a xeno-artery patch model ex vivo, ibrutinib inhibited the proliferation of PBMCs (POD 14-42), mainly CD3+CD4+ and CD3+CD8+ T cells ex vivo. The secretion of cytokines (IL-6, IL-2 and IFN-γ) was suppressed in response to ibrutinib. In allo-skin transplantation models, ibrutinib delayed the rejection of grafted skins. Ibrutinib decreased the amount of T/B cells and lymphocyte infiltration. Altogether, ibrutinib exhibited immunosuppressive potential through cytokine regulation and T cell inhibition ex vivo and in vitro. Repositioning of ibrutinib as an immunosuppressant will greatly facilitate novel immunosuppressant development.


Asunto(s)
Reposicionamiento de Medicamentos , Inmunosupresores/uso terapéutico , Pirazoles/uso terapéutico , Pirimidinas/uso terapéutico , Trasplantes , Adenina/análogos & derivados , Animales , Femenino , Inmunosupresores/farmacología , Leucocitos Mononucleares , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Piperidinas , Pirazoles/farmacología , Pirimidinas/farmacología , Porcinos , Trasplante Homólogo
18.
Neurosurg Rev ; 41(3): 877-890, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29280021

RESUMEN

The goals of this study were to analyze the incidence, clinical manifestations, neuroimaging findings, surgical treatments, and neurological outcomes of trigonal cavernous malformations (TCMs). Among 1395 cases of intracranial and intraspinal cavernous malformations (CMs) surgically treated between 2003 and 2016 at Beijing Tiantan Hospital, a series of 12 patients with TCM was chosen for analysis and their records were reviewed. We also performed an exhaustive literature search using PubMed to identify all previously reported cases in the literatures. TCMs accounted for 0.86% of the entire series of the central nervous system (CNS) CMs. The case series consisted of five male and seven female patients (ratio 1:1.4), with an average age at presentation of 32.9 years (7-53 years). In all the cases, headache was the most common initial symptom (66.7%). Complete resection without surgical mortality was achieved in all the cases. Postoperative complications included fever, lower limb weakness, sensory aphasia, and calculational capacity declination. Follow-up period after diagnosis was 15 to 74 months (mean 48.3 months); no patient was lost to follow-up. All the patients were considered to be in excellent clinical condition. TCMs are rare lesions; they can reach large size, and their symptoms and signs commonly resulted from mass effect. Surgical intervention is the treatment of choice for TCMs; patients can obtain favorable neurological outcomes after complete resection.


Asunto(s)
Hemangioma Cavernoso del Sistema Nervioso Central/fisiopatología , Hemangioma Cavernoso del Sistema Nervioso Central/cirugía , Procedimientos Neuroquirúrgicos/métodos , Adolescente , Adulto , Encéfalo/diagnóstico por imagen , Niño , Embolización Terapéutica , Femenino , Estudios de Seguimiento , Cefalea/etiología , Hemangioma Cavernoso del Sistema Nervioso Central/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven
19.
Neurosurg Rev ; 41(3): 799-811, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29199381

RESUMEN

Cavernous malformations (CMs) located at the foramen of Monro (FM) are relatively rare benign vascular malformations. Knowledge of FM CM is poor. The aims of this study were to describe the incidence, clinical presentation, radiological features, surgical approaches, and neurological outcomes for FM CM patients and to discuss the treatment strategy for this disease. We present a series of nine FM CM patients (four males, five females; mean age 29.3 years) who were treated at a single neurosurgical center. FM CM accounted for 0.56% of the entire series of the central nervous system (CNS) CMs. Headache accompanied by nausea and vomiting was the most common initial symptom (55.6%). The mean preoperative Karnofsky Performance Scale (KPS) score was 84.4 (range 70-100). In all but one patient, the lesions were surgically resected. Postoperatively, two patients developed obstructive hydrocephalus, and one experienced motor aphasia and right hemiparesis. At the time of discharge, the KPS score improved to a mean of 88.9. Follow-up period after diagnosis was 18 to 131 months (mean 69.7 months); all the patients were considered to be in excellent clinical condition. FM CMs are rare and challenging lesions; they have a female predilection. The most common clinical manifestations of FM CM are the symptoms of mass effect. The seizure risk of FM CMs seems to be significantly lower than that of general intraventricular CMs. Early surgical intervention should be offered to symptomatic cases, and gross total resection is associated with favorable neurological outcomes.


Asunto(s)
Ventrículos Cerebrales/patología , Ventrículos Cerebrales/cirugía , Hemangioma Cavernoso del Sistema Nervioso Central/patología , Hemangioma Cavernoso del Sistema Nervioso Central/cirugía , Procedimientos Neuroquirúrgicos/métodos , Adolescente , Adulto , Ventrículos Cerebrales/diagnóstico por imagen , Niño , Femenino , Estudios de Seguimiento , Cefalea/etiología , Hemangioma Cavernoso del Sistema Nervioso Central/epidemiología , Humanos , Incidencia , Estado de Ejecución de Karnofsky , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Factores Sexuales , Resultado del Tratamiento , Adulto Joven
20.
Water Sci Technol ; 78(5-6): 1001-1009, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30339525

RESUMEN

In this work, the novel ß-cyclodextrin modified mesostructured silica coated multi-walled carbon nanotubes (MWCNTs) composites were synthesized and applied for the removal of parabens in aqueous solution. The prepared MWCNTs/SiO2/ß-CD composites were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy and thermogravimetric analysis. The effects of the amount of adsorbent, pH and elution solvents on the removal efficiency of parabens from water solutions were investigated. Under the optimized conditions, over 95% removal efficiency was achieved by using 40 mg of MWCNTs/SiO2/ß-CD adsorbents to absorb the parabens from 60 mL of 0.5 µg/mL parabens solutions. The solution pH in the range from 5 to 9 has no influence on the removal efficiency and the parabens sorption capacity of the prepared adsorbents were around 0.75 µg/mg. Furthermore, the stability and reusability studies demonstrated that the prepared MWCNTs/SiO2/ß-CD composites are cost-effective adsorbents for the removal of parabens from water with high regeneration efficiency. The composites fabricated in this study could become an attractive candidate for water purification.


Asunto(s)
Nanotubos de Carbono/química , Parabenos/química , Dióxido de Silicio/química , Adsorción , Microscopía Electrónica de Rastreo , Solventes/química , Espectroscopía Infrarroja por Transformada de Fourier , Agua/química , Contaminantes Químicos del Agua , Purificación del Agua/métodos , Difracción de Rayos X , beta-Ciclodextrinas/química
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