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1.
ACS Appl Mater Interfaces ; 16(20): 25923-25937, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38725122

RESUMEN

The management of severe full-thickness skin defect wounds remains a challenge due to their irregular shape, uncontrollable bleeding, high risk of infection, and prolonged healing period. Herein, an all-in-one OD/GM/QCS@Exo hydrogel was prepared with catechol-modified oxidized hyaluronic acid (OD), methylacrylylated gelatin (GM), and quaternized chitosan (QCS) and loaded with adipose mesenchymal stem cell-derived exosomes (Exos). Cross-linking of the hydrogel was achieved using visible light instead of ultraviolet light irradiation, providing injectability and good biocompatibility. Notably, the incorporation of catechol groups and multicross-linked networks in the hydrogels conferred strong adhesion properties and mechanical strength against external forces such as tensile and compressive stress. Furthermore, our hydrogel exhibited antibacterial, anti-inflammatory, and antioxidant properties along with wound-healing promotion effects. Our results demonstrated that the hydrogel-mediated release of Exos significantly promotes cellular proliferation, migration, and angiogenesis, thereby accelerating skin structure reconstruction and functional recovery during the wound-healing process. Overall, the all-in-one OD/GM/QCS@Exo hydrogel provided a promising therapeutic strategy for the treatment of full-thickness skin defect wounds through actively participating in the entire process of wound healing.


Asunto(s)
Quitosano , Exosomas , Gelatina , Ácido Hialurónico , Hidrogeles , Células Madre Mesenquimatosas , Piel , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Hidrogeles/química , Hidrogeles/farmacología , Animales , Exosomas/química , Exosomas/metabolismo , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Piel/efectos de los fármacos , Piel/patología , Piel/efectos de la radiación , Quitosano/química , Quitosano/farmacología , Ratones , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Gelatina/química , Gelatina/farmacología , Luz , Humanos , Antibacterianos/química , Antibacterianos/farmacología , Proliferación Celular/efectos de los fármacos
2.
Opt Express ; 31(21): 34154-34168, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37859178

RESUMEN

This paper proposes an all-optical second-order ordinary differential equation (SODE) solver based on a single microdisk resonator. We validate the feasibility of our structure for constant and complex coefficient SODE solutions for Gaussian and super-Gaussian pulses. The results demonstrate a good agreement between the solutions obtained with the designed structure and those obtained through mathematical calculations for both constant and complex coefficient SODEs. We also discuss the influence of input optical signal pulse width on solution result deviations. Furthermore, we validate the capability of the designed structure to achieve tunable solutions for complex-coefficient SODEs with a tuning power of less than 10 mW. The device footprint is approximately 20×30 µm2, and it is 3-4 times smaller than the current smallest solving unit. The maximum Q-factor reaches 9.8×104. The proposed device avoids the traditional approach of cascading two resonators for SODE solving. Moreover, achieving mode alignment within the same resonator reduces the process challenges associated with aligning multiple devices in a cascade. Furthermore, it offers wider applicability for solving SODEs, namely, the ability to solve both constant and complex coefficient SODEs with complete derivative terms.

3.
Biol Trace Elem Res ; 2023 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-37897593

RESUMEN

Drug combination is considered to be an effective approach to improve the efficacy of cancer therapy and chemoprevention. Selenite, a representative of inorganic form of selenium, and butyrate, a major short-chain fatty acid, are two well-documented colon cancer dietary chemopreventive agents with distinct molecular mechanisms. We hypothesized that combination of selenite and butyrate might produce improved outcome against colon cancer. This hypothesis was tested using both HCT116 human colon cancer cells and its xenograft mouse model in the present study. The in vitro study showed a synergistically inhibitory effect on HCT116 colon cancer cells but not on NCM460 normal human colon mucosal epithelial cells. Consistent with the in vitro study, results of the xenograft mouse model further demonstrated that combination of selenite and butyrate led to improved efficacy in comparison with each agent alone. Mechanistically, the induction of alanine-serine-cysteine transporter 2 (ASCT2) by selenite repressed its inhibitory effect on colon cancer cells, which was reversed by its co-treatment with butyrate. The findings of the present study denote the likely potential for developing selenite/butyrate combination remedy to combat against colon cancer.

4.
Int J Biol Macromol ; 225: 90-102, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36509201

RESUMEN

Preparing sponge dressings with stable wet adhesion remains difficult in wound repair, especially in burn wounds with bleeding and large amounts of exudate. In this work, a multifunctional hybrid sponge dressing (DHGT+PHMB+TiO2NPs) with good wet adhesion was developed by combining biomimetic and enzymatic cross-linking reactions. The sponge dressing matrix (DHGT) was prepared by tyrosinase-catalyzed cross-linking of dopamine-modified hyaluronic acid (DOPA-HA) and gelatin. The multifunctional hybrid sponge dressing was obtained by loading polyhexamethylene biguanide (PHMB) and titanium dioxide nanoparticles (TiO2NPs) onto the DHGT matrix. The newly developed sponge dressing exhibited high mechanical properties, good wet adhesion, antibacterial activity, reactive oxygen species (ROS) scavenging, biocompatibility, and excellent hemostasis ability. In vivo studies showed that the multifunctional hybrid sponge dressing could significantly accelerate the healing of infected full-thickness burn wounds by inhibiting bacterial growth, accelerating skin tissue reepithelialization, collagen deposition, and angiogenesis, as well as regulating the expression of inflammatory factors and cytokines.


Asunto(s)
Biomimética , Quemaduras , Humanos , Cicatrización de Heridas , Piel , Vendajes , Quemaduras/tratamiento farmacológico , Antibacterianos/farmacología
5.
Sensors (Basel) ; 22(6)2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35336428

RESUMEN

Deep learning-based image dehazing methods have made great progress, but there are still many problems such as inaccurate model parameter estimation and preserving spatial information in the U-Net-based architecture. To address these problems, we propose an image dehazing network based on the high-resolution network, called DeHRNet. The high-resolution network originally used for human pose estimation. In this paper, we make a simple yet effective modification to the network and apply it to image dehazing. We add a new stage to the original network to make it better for image dehazing. The newly added stage collects the feature map representations of all branches of the network by up-sampling to enhance the high-resolution representations instead of only taking the feature maps of the high-resolution branches, which makes the restored clean images more natural. The final experimental results show that DeHRNet achieves superior performance over existing dehazing methods in synthesized and natural hazy images.

6.
Sci Total Environ ; 744: 140986, 2020 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-32755788

RESUMEN

Water shortage has become a serious problem for the sustainable development of irrigated agriculture in arid regions. In these areas, the scale and planting structure of agriculture suitable for local water resources is particularly important. Irrigation water demand is a crucial indicator of water requirement in irrigation districts. In this study, Mann-Kendall method was used to analyze the temporal changes of climatic factors of the past 50 years and ArcGis to determine spatial changes in human activities. The path analysis was used to quantitative characterize direct and indirect effects of these factors on irrigation water demand and suggest how human activity can be altered to reduce irrigation water demand. The results show that temperature has risen significantly since the completion of the second-stage irrigation district, wind speed has dropped since the completion of the first-stage irrigation district, and cultivated land area has greatly expanded. The direct impact and comprehensive effect of planting area on irrigation water demand is the largest. Controlling for the total water intake, the maximum agricultural planting scale is 40,133 ha. Through adjustment of the planting structure, the scale of irrigated agriculture could increase by as much as 25.8%. Therefore, agricultural planting structures and planting scales suitable for local water resources should be put into action for future sustainable development of agriculture.

7.
Opt Express ; 26(16): 19742-19749, 2018 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-30119295

RESUMEN

We present the first demonstration of a 4λ transmitter optical sub-assembly (TOSA) on the coarse wavelength division multiplexing (CWDM) grid, i.e., 20 nm spacing, targeting 400G-FR4 requirements over 2 km. The TOSA is based on uncooled InP external modulated laser (EML) technology and it utilizes four EMLs followed by a CWDM multiplexer. We characterize the performance of the TOSA versus received optical modulation amplitude (OMA), number of equalizer taps, reach, modulation format, TOSA case temperature, and bit rate. Four 53 Gbaud 4-level pulse amplitude modulation (PAM4) RF signals are used to drive the TOSA achieving a net rate of 400 Gb/s. Results reveal that 400 Gb/s can be transmitted over 2 km of single mode fiber (SMF) at a bit error rate (BER) below the KP4- forward error correction (KP4-FEC) threshold (i.e., 2.4 × 10-4) using only a 5 tap feed forward equalizer at the receiver. To the best of our knowledge, this is the first demonstration of 400 Gb/s using a 4λ CWDM TOSA over 2 km of SMF. Moreover, we achieve 400 Gb/s and 600 Gb/s over 20 km and 10 km below KP4-FEC and the 7% hard-decision FEC (HD-FEC) (i.e., 3.8 × 10-3) thresholds, respectively, without optical amplification. Furthermore, we show the performance of the TOSA against temperature, where it shows no significant change in the BER performance from 20 °C to 60 °C. Finally, we compare the performance of PAM2, PAM4, and PAM8 modulation formats where we show the possibility of achieving 400 Gb/s aggregate bit rate using 42 Gbaud PAM8 modulation format at the expense of utilizing a stronger FEC.

8.
Sci Rep ; 4: 7377, 2014 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-25488111

RESUMEN

Multi-wavelength semiconductor laser arrays (MLAs) have wide applications in wavelength multiplexing division (WDM) networks. In spite of their tremendous potential, adoption of the MLA has been hampered by a number of issues, particularly wavelength precision and fabrication cost. In this paper, we report high channel count MLAs in which the wavelengths of each channel can be determined precisely through low-cost standard µm-level photolithography/holographic lithography and the reconstruction-equivalent-chirp (REC) technique. 60-wavelength MLAs with good wavelength spacing uniformity have been demonstrated experimentally, in which nearly 83% lasers are within a wavelength deviation of ±0.20 nm, corresponding to a tolerance of ±0.032 nm in the period pitch. As a result of employing the equivalent phase shift technique, the single longitudinal mode (SLM) yield is nearly 100%, while the theoretical yield of standard DFB lasers is only around 33.3%.

9.
Opt Express ; 21(22): 26936-41, 2013 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-24216916

RESUMEN

We report the first laterally-coupled distributed feedback (LC-DFB) laser with a quarter-wave equivalent phase shift (EPS) realized by interference lithography (IL) and conventional photolithography. A specially designed sampled grating is fabricated on both sidewalls of a ridge waveguide to provide a quarter-wave EPS at the center of the cavity. The resulting laser exhibits stable single-mode lasing operation over a wide range of injection currents, with a side mode suppression ratio (SMSR) of 41.1 dB. This provides a practical, low-cost method to fabricate quarter-wave phase shifted DFB lasers with high performance without any epitaxial regrowth or the use of electron-beam lithography, thereby simplifying the fabrication of DFB lasers with stable and precise wavelengths, as single devices or as arrays in photonic integrated circuits.

10.
Nat Prod Res ; 27(23): 2183-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23859601

RESUMEN

Three novel metabolites (1, 5 and 10) were isolated from a 25-L fermentation broth of Actinomyces sp. JN411010 together with 11 related compounds. Their structures were determined on the basis of 1D and 2D NMR, as well as HR-ESI-MS spectroscopic data analyses. Compounds 1-2, 5-8 and 10 displayed moderate antimicrobial activities against Gram-positive and Gram-negative bacteria. Biosynthetic pathway of 5 and 10 was proposed to be catalysed by polyketide and non-ribosomal peptide gene clusters, respectively.


Asunto(s)
Actinobacteria/metabolismo , Antibacterianos/biosíntesis , Ciervos/microbiología , Animales , Antibacterianos/farmacología , Fermentación , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Prenilación , Espectrometría de Masa por Ionización de Electrospray
11.
Opt Express ; 17(7): 5240-5, 2009 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-19333287

RESUMEN

In this paper we report, to the best of our knowledge, the first experimental realization of distributed feedback (DFB) semiconductor lasers based on reconstruction-equivalent-chirp (REC) technology. Lasers with different lasing wavelengths are achieved simultaneously on one chip, which shows a potential for the REC technology in combination with the photonic integrated circuits (PIC) technology to be a possible method for monolithic integration, in that its fabrication is as powerful as electron beam technology and the cost and time-consuming are almost the same as standard holographic technology.


Asunto(s)
Tecnología de Fibra Óptica/instrumentación , Láseres de Semiconductores , Procesamiento de Señales Asistido por Computador/instrumentación , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Retroalimentación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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