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1.
Opt Lett ; 48(21): 5747-5750, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37910749

RESUMEN

While higher-order photonic topological corner states typically are created in systems with nontrivial bulk dipole polarization, they could also be created in systems with vanishing dipole polarization but with nontrivial quadrupole topology, which though is less explored. In this work, we show that simple all-dielectric photonic crystals in the Lieb lattice can host a topologically nontrivial quadrupole bandgap. Through a combination of symmetry analysis of the eigenmodes and explicit calculations of the Wannier bands and their polarization using the Wilson loop method, we demonstrate that the Lieb photonic crystals can have a bandgap with vanishing dipole polarization but with nontrivial quadrupole topology. The nontrivial bulk quadrupole moment could result in edge-localized polarization and topological corner states in systems with open edges. Interestingly, the indices of the corner states show an unusual "3+1" pattern compared to previously known "2+2" pattern, and this new pattern leads to unusual filling anomaly when the corner states are filled. Our work could not only deepen our understanding about quadrupole topology in simple all-dielectric photonic crystals but could also offer new opportunities for practical applications in integrated photonic devices.

2.
Small ; 18(48): e2204443, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36257819

RESUMEN

Earth-abundant tungsten carbide exhibits potential hydrogen evolution reaction (HER) catalytic activity owing to its Pt-like d-band electronic structure, which, unfortunately, suffers from the relatively strong tungsten-hydrogen binding, deteriorating its HER performance. Herein, a catalyst design concept of incorporating late transition metal into early transition metal carbide is proposed for regulating the metal-H bonding strength and largely enhancing the HER performance, which is employed to synthesize CoW bi-metallic carbide Co6 W6 C by a "disassembly-assembly" approach in a confined environment. Such synthesized Co6 W6 C nanocatalyst features the optimal Gibbs free energy of *H intermediate and dissociation barrier energy of H2 O molecules as well by taking advantage of the electron complementary effect between Co and W species, which endows the electrocatalyst with excellent HER performance in both alkaline and seawater/alkaline electrolytes featuring especially low overpotentials, elevated current densities, and much-enhanced operation durability in comparison to commercial Pt/C catalyst. Moreover, a proof-of-concept Mg/seawater battery equipped with Co6 W6 C-2-600 as cathode offers a peak power density of 9.1 mW cm-2 and an open-circuit voltage of ≈1.71 V, concurrently realizing hydrogen production and electricity output.

3.
Opt Express ; 30(21): 37484-37492, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36258336

RESUMEN

Long-range light detection and ranging (lidar) of active illumination optical imaging has widespread applications, such as remote sensing, satellite-based global topography, and target recognition and identification. Here, to make trade-offs among imaging efficiency, resolution, receiving field of view, divergence angle, and detected distance, we demonstrate a scanning single-pixel imaging lidar (SSPIL), enjoying the merits of the traditional pointing-by-pointing scanning imaging and single-pixel imaging. The imaging strategy of SSPIL is divided into scanning search and staring imaging processes. These strategies can save most time consumption for imaging background areas and thus improve imaging efficiency. Three imaging experiments were conducted in real urban atmospheric conditions. The preliminary results show SSPIL has the ability for long-range imaging with high efficiency, high resolution, and a large receiving field of view. Also, from the imaging results, we found that multiple samples can improve the SNR of imaging in the real urban atmosphere. The present work may provide a valuable alternative approach in the long-range active illumination optical imaging fields.

4.
Opt Lett ; 47(12): 3123-3126, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35709066

RESUMEN

Single-pixel imaging (SPI), a novel computational imaging technique that has emerged in the past decades, can effectively capture the image of a static object by consecutively measuring light intensities from it. However, when SPI is applied to imaging the dynamic object, severe motion blur in the restored image tends to appear. In this Letter, a new SPI scheme is proposed to largely alleviate such a problem by leveraging a calibrated radon spectrum. Such a spectrum is obtained by translating the acquired one-dimensional projection functions (1DPFs) according to the positional relationship among the 1DPFs. Simulation and experimental results demonstrate that, without prior knowledge, our approach can effectively reduce motion blur and restore high-quality images of the fast-moving object. In addition, the proposed scheme can also be used for fast object tracking.


Asunto(s)
Radón , Simulación por Computador , Diagnóstico por Imagen , Movimiento (Física)
5.
Opt Lett ; 47(4): 870-873, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35167546

RESUMEN

Target tracking has found important applications in particle tracking, vehicle navigation, aircraft monitoring, etc. However, employing single-pixel imaging techniques to track a fast-moving object with a high frame rate is still a challenge, due to the limitation of the modulation frequency of the spatial light modulator and the number of required patterns. Here we report a complementary single-pixel object tracking approach which requires only two geometric moment patterns to modulate the reflected light from a moving object in one frame. Using the complementary nature of a digital micromirror device (DMD), two identical single-pixel detectors are used to measure four intensities which can be used to acquire the values of zero-order and first-order geometric moments to track the centroid of a fast-moving object. We experimentally demonstrate that the proposed method successfully tracks a fast-moving object with a frame rate of up to 11.1 kHz in the first two experiments. In the third experiment, we compare previous works and find that the method can also accurately track a fast-moving object with a changing size and moving speed of 41.8 kilopixel/s on the image plane. The root mean squared errors in the transverse and axial directions are 0.3636 and 0.3640 pixels, respectively. The proposed method could be suitable for ultrafast target tracking.

6.
Appl Opt ; 61(23): 6905-6914, 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-36255772

RESUMEN

Single-pixel imaging (SPI) is a new technology with many applications and prospects. Polarization detection technology can improve the detection and identification ability of the imaging system. A near-infrared polarization SPI lidar system is designed to realize detection and polarization imaging of outdoor long-range targets. The depth, intensity, linear polarization, and polarization degree images of typical remote targets are obtained. The results show that the polarization image contains many details and contour information of the target, and the intensity image contains brightness and reflectivity information. Intensity and polarization information complement each other. The characteristics of intensity and polarization images at different spatial frequencies are analyzed for the first time, to our knowledge, by taking advantage of the Fourier modulation mode. We found that the proportion of high-frequency information in the polarization image is much higher than that of the intensity image. The sampling strategy of collecting only low-frequency components is applicable in intensity imaging but needs further improvement in polarization imaging. The polarization SPI lidar system can enrich the target information acquired, improve imaging contrast, and have significant application value for target detection and identification in complex backgrounds.

7.
Angew Chem Int Ed Engl ; 61(15): e202116290, 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35075773

RESUMEN

Fe-N-C electrocatalysts have been demonstrated to be the most promising substitutes for benchmark Pt/C catalysts for the oxygen reduction reaction (ORR). Herein, we report that N-doped carbon materials with trace amounts of iron (0-0.08 wt. %) show excellent ORR activity and durability comparable and even superior to those of Pt/C in both alkaline and acidic media without significant contribution by the metal sites. Such an N-doped carbon (denoted as N-HPCs) features a hollow and hierarchically porous architecture, and more importantly, a noncovalently bonded N-deficient/N-rich heterostructure providing the active sites for oxygen adsorption and activation owing to the efficient electron transfer between the layers. The primary Zn-air battery using N-HPCs as the cathode delivers a much higher power density of 158 mW cm-2 , and the maximum power density in the H2 -O2 fuel cell reaches 486 mW cm-2 , which is comparable to and even better than those using conventional Fe-N-C catalysts at cathodes.

8.
Angew Chem Int Ed Engl ; 61(32): e202207226, 2022 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-35638129

RESUMEN

A novel Zn-Fe flow battery featuring an Fe3+ reduction reaction (Fe3+ RR)-coupled zinc oxidation, and an Fe2+ oxidation reaction (Fe2+ OR)-coupled hydrogen evolution reaction (HER) system as well, was established. This battery is capable of driving two Fe2+ OR-coupled HER systems in series based on the above Fe2+ /Fe3+ cycling, for efficient self-powered hydrogen evolution. Meanwhile, this Fe2+ /Fe3+ cycling enables the preparation of a multifunctional catalyst, Pt-3@SXNS (siloxene nanosheet), by the Fe2+ OR-promoted dispersion of Pt nanoparticles on SXNS; alternatively, this support could be obtained by Fe3+ RR-assisted exfoliation using Fe3+ from the anolyte of Fe2+ OR-coupled HER. The Pt-3@SXNS catalyst exhibits excellent catalytic activities toward Fe3+ RR in the Zn-Fe flow battery, HER, and Fe2+ OR in the electrolyzer, which is attributed to the strong electronic interaction between Pt and Si. This work offers a new strategy for energy storage and low-cost hydrogen production from acidic wastewater.

9.
Opt Express ; 29(19): 30327-30336, 2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34614758

RESUMEN

Real-time tracking of fast-moving object have many important applications in various fields. However, it is a great challenge to track of fast-moving object with high frame rate in real-time by employing single-pixel imaging technique. In this paper, we present the first single-pixel imaging technique that measures zero-order and first-order geometric moments, which are leveraged to reconstruct and track the centroid of a fast-moving object in real time. This method requires only 3 geometric moment patterns to illuminate a moving object in one frame. And the corresponding intensities collected by a single-pixel detector are equivalent to the values of the zero-order and first-order geometric moments. We apply this new approach of measuring geometric moments to object tracking by detecting the centroid of the object in two experiments. The root mean squared errors in the transverse and axial directions are 5.46 pixels and 5.53 pixels respectively, according to the comparison of data captured by a camera system. In the second experiment, we successfully track a moving magnet with a frame rate up to 7400 Hz. The proposed scheme provides a new method for ultrafast target tracking applications.

10.
Sensors (Basel) ; 20(5)2020 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-32155932

RESUMEN

The deviation between the two oscillators in BiSAR systems will cause a residual modulation of echo signal. Therefore, the phase synchronization is an important issue that must be addressed for BiSAR systems. An advanced non-interrupted phase synchronization scheme is used for the LuTan-1 SAR satellite. The synchronization transceiver (STR) is designed for transmitting and receiving synchronization signals. In addition, STR mainly consists of master and auxiliary transceivers and switch module. Furthermore, the function and working principle of STR are introduced, and the detailed design of each part is described. The measured results are also evaluated to prove the performance of the STR. In addition, the phase synchronization accuracy is also demonstrated to verify the effectiveness of the non-interrupted synchronization scheme. The standard deviation (STD) of the residual phase is less than 0.3 degrees. The results have guiding significance for the synchronization unit design of LuTan-1 and the future BiSAR system.

11.
Sensors (Basel) ; 20(11)2020 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-32512743

RESUMEN

Phase synchronization is one of the key technical challenges and prerequisites for the bistatic synthetic aperture radar (SAR) system, which can form a single-pass interferometry system to perform topographic mapping. In this paper, an advanced phase synchronization scheme based on a pulsed signal at carrier frequency is proposed for a bistatic SAR system and it is verified by a ground validation system. In the proposed phase synchronization scheme, the pulsed signal at carrier frequency is used for phase synchronization link, and it is exchanged by virtue of a time slot between radar signals. The feasibility of the scheme is proven by theoretical analysis of various factors affecting the performance of phase synchronization, and the reliability of the scheme is verified by the test results of the ground validation system.

12.
J Physiol ; 597(12): 3085-3105, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31050811

RESUMEN

KEY POINTS: This work confirms previous reports that CM4620, a small molecule inhibitor of Ca2+ entry via store operated Ca2+ entry (SOCE) channels formed by stromal interaction molecule 1 (STIM1)/Orai complexes, attenuates acinar cell pathology and acute pancreatitis in mouse experimental models. Here we report that intravenous administration of CM4620 reduces the severity of acute pancreatitis in the rat, a hitherto untested species. Using CM4620, we probe further the mechanisms whereby SOCE via STIM1/Orai complexes contributes to the disease in pancreatic acinar cells, supporting a role for endoplasmic reticulum stress/cell death pathways in these cells. Using CM4620, we show that SOCE via STIM1/Orai complexes promotes neutrophil oxidative burst and inflammatory gene expression during acute pancreatitis, including in immune cells which may be either circulating or invading the pancreas. Using CM4620, we show that SOCE via STIM1/Orai complexes promotes activation and fibroinflammatory gene expression within pancreatic stellate cells. ABSTRACT: Key features of acute pancreatitis include excess cellular Ca2+ entry driven by Ca2+ depletion from the endoplasmic reticulum (ER) and subsequent activation of store-operated Ca2+ entry (SOCE) channels in the plasma membrane. In several cell types, including pancreatic acinar, stellate cells (PaSCs) and immune cells, SOCE is mediated via channels composed primarily of Orai1 and stromal interaction molecule 1 (STIM1). CM4620, a selective Orai1 inhibitor, prevents Ca2+ entry in acinar cells. This study investigates the effects of CM4620 in preventing or reducing acute pancreatitis features and severity. We tested the effects of CM4620 on SOCE, trypsinogen activation, acinar cell death, activation of NFAT and NF-κB, and inflammatory responses in ex vivo and in vivo rodent models of acute pancreatitis and human pancreatic acini. We also examined whether CM4620 inhibited cytokine release in immune cells, fibro-inflammatory responses in PaSCs, and oxidative burst in neutrophils, all cell types participating in pancreatitis. CM4620 administration to rats by i.v. infusion starting 30 min after induction of pancreatitis significantly diminished pancreatitis features including pancreatic oedema, acinar cell vacuolization, intrapancreatic trypsin activity, cell death signalling and acinar cell death. CM4620 also decreased myeloperoxidase activity and inflammatory cytokine expression in pancreas and lung tissues, fMLF peptide-induced oxidative burst in human neutrophils, and cytokine production in human peripheral blood mononuclear cells (PBMCs) and rodent PaSCs, indicating that Orai1/STIM1 channels participate in the inflammatory responses of these cell types during acute pancreatitis. These findings support pathological Ca2+ entry-mediated cell death and proinflammatory signalling as central mechanisms in acute pancreatitis pathobiology.


Asunto(s)
Amidinas/uso terapéutico , Antiinflamatorios/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Proteína ORAI1/antagonistas & inhibidores , Pancreatitis/tratamiento farmacológico , Prolina/análogos & derivados , Células Acinares/metabolismo , Amidinas/farmacología , Animales , Antiinflamatorios/farmacología , Calcio/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Ceruletida , Citocinas/metabolismo , Humanos , Leucocitos Mononucleares/metabolismo , Masculino , Ratones Endogámicos C57BL , Células Estrelladas Pancreáticas/metabolismo , Pancreatitis/inducido químicamente , Pancreatitis/inmunología , Pancreatitis/metabolismo , Peroxidasa/metabolismo , Prolina/farmacología , Prolina/uso terapéutico , Ratas , Superóxidos/metabolismo
13.
Lab Invest ; 99(12): 1861-1873, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31409891

RESUMEN

Hypertrophic scars (HSs) are characterized by fibroblast hyperproliferation and excessive matrix deposition. During wound healing, transforming growth factor (TGF)-ß1/Smad signaling acts as a key regulator. As a transcriptional corepressor of TGF-ß1/Smads, SnoN is expressed at low levels in many fibrotic diseases due to TGF-ß1/Smad-induced degradation. SnoN residue (1-366; SR) is resistant to TGF-ß1-induced degradation. However, the expression and role of SR in HSs are unknown. Here, we inhibited TGF-ß1/Smad signaling via overexpression of SR to block fibroblast transdifferentiation, proliferation, and collagen deposition during HS formation. Our results showed that SnoN was downregulated in HS fibroblasts (HSFs) owing to TGF-ß1/Smad-induced degradation. Overexpression of SR in normal human dermal fibroblasts (NHDFs) and HSFs successfully blocked phosphorylation of Smad2 and Smad3, thereby inhibiting NHDF transdifferentiation and HSF proliferation and reducing type I collagen (ColI) and type III collagen (ColIII) production and secretion. In addition, we applied overexpressed full-length SnoN (SF) and SR to wound granulation tissue in a rabbit model of HSs. SR reduced wound scarring, improved collagen deposition and arrangement of scar tissue, and decreased mRNA and protein expression of ColI, ColIII, and α-smooth muscle actin (α-SMA) more effectively than SF in vivo. These results suggest that SR could be a promising therapy for the prevention of HS.


Asunto(s)
Cicatriz Hipertrófica/prevención & control , Fibroblastos/metabolismo , Terapia Genética , Péptidos y Proteínas de Señalización Intracelular/uso terapéutico , Proteínas Proto-Oncogénicas/uso terapéutico , Adolescente , Adulto , Animales , Cicatriz Hipertrófica/metabolismo , Matriz Extracelular/metabolismo , Femenino , Humanos , Hiperplasia/prevención & control , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Lentivirus , Masculino , Persona de Mediana Edad , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Conejos , Distribución Aleatoria , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Ubiquitina/metabolismo , Adulto Joven
14.
Zhongguo Zhong Yao Za Zhi ; 43(12): 2470-2473, 2018 Jun.
Artículo en Zh | MEDLINE | ID: mdl-29950062

RESUMEN

There are 400 thousand patients with long-term hemodialysis in China nowadays. Hemodialysis, as the most common alternative to renal replacement therapy, prolongs the life span of patients with end stage renal failure. However, there are still many complications of hemodialysis treatment. These complications reduce the quality of life of patients and may even endanger their life, and sometimes they are difficult to deal with. Classical prescriptions, commonly referred to as classical effective prescriptions in modern medicine, mainly indicating the formulas recorded in Treatise on Febrile Diseases and Synopsis of Golden Chamber, were relative to contemporary prescriptions emerging after Song and Yuan dynasties. Prescriptions corresponding to syndromes means one-to-one correspondence between syndromes and prescriptions, with many advantages and that is the key of clinical efficacy. Many complications of hemodialysis patients have typical clinical manifestations, which can match the syndromes corresponding to classical prescriptions, thus quickly relieving the symptoms of patients in clinical application. Six clinical cases of dialysis muscle spasm, disequilibrium syndrome, restless legs syndrome, uremic encephalopathy, post dialysis arrhythmia, and secondary hyperparathyroidism were used in this paper, to explore the intervention strategies for hemodialysis related complications.


Asunto(s)
Fallo Renal Crónico/complicaciones , Diálisis Renal , China , Humanos , Calidad de Vida
15.
Zhongguo Dang Dai Er Ke Za Zhi ; 20(1): 32-36, 2018 Jan.
Artículo en Zh | MEDLINE | ID: mdl-29335079

RESUMEN

OBJECTIVE: To study the expression of plasma miRNA-497 in children with sepsis-induced myocardial injury and its clinical significance. METHODS: A total of 148 children with sepsis were enrolled. According to the presence or absence of myocardial injury, these children were divided into myocardial injury group (n=58) and non-myocardial injury group (n=90). The two groups were compared in terms of the changes in plasma levels of miRNA-497, cardiac troponin I (cTnI), creatine kinase-MB (CK-MB), N-terminal pro-brain natriuretic peptide (NT-proBNP), procalcitonin (PCT), and C-reactive protein (CRP) and left ventricular ejection fraction (LVEF). The receiver operating characteristic (ROC) curve was plotted to evaluate the value of plasma miRNA-497, cTnI, and CK-MB in the diagnosis of myocardial injury. A Pearson correlation analysis was used to determine the correlation of miRNA-497 with cTnI, CK-MB, NT-proBNP, PCT, CRP, and LVEF. RESULTS: Compared with the non-myocardial injury group, the myocardial injury group had significantly higher plasma levels of miRNA-497, cTnI, CK-MB, NT-proBNP, PCT, and CRP (P<0.05). Plasma miRNA-497, cTnI, and CK-MB when measured alone or in combination had an area under the ROC curve of 0.918, 0.931, 0.775, and 0.940 respectively. At the optimal cut-off value of 2.05, miRNA-497 had a sensitivity of 90.4% and a specificity of 91.2%. The correlation analysis showed that there was a good correlation between plasma miRNA-497 and cTnI in children with myocardial injury (r=0.728, P<0.01). CONCLUSIONS: Plasma miRNA-497 has a similar value as cTnI in the diagnosis of sepsis-induced myocardial injury in children and may be used as a potential marker for early diagnosis of myocardial injury.


Asunto(s)
Cardiomiopatías/etiología , MicroARNs/sangre , Sepsis/complicaciones , Cardiomiopatías/sangre , Niño , Preescolar , Forma MB de la Creatina-Quinasa/sangre , Femenino , Humanos , Lactante , Masculino , Troponina I/sangre
16.
Cell Physiol Biochem ; 43(5): 1829-1840, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29050003

RESUMEN

BACKGROUND/AIMS: Cantharidin, a type of terpenoid secreted by the blister beetle Mylabris phalerata (Pallas), has attracted great attention in cancer therapy because of its potential anti-cancer activities. Here, we report the effects on apoptosis and autophagy in human triple-negative breast cancer (TNBC) cell lines after treatment with cantharidin and attempt to elucidate the underlying mechanisms. METHODS: MDA-MB-231 and MDA-MB-468 cells were treated with cantharidin and cell proliferation was examined using CCK-8 and clone formation assays. The expression of apoptosis- and autophagy-associated proteins was detected by western blotting. Cells were infected with lentivirus carrying the Beclin-1 gene, and MDA-MB-231-beclin1 (MB231-Bec) and MDA-MB-468-beclin-1(MB468-Bec) cells stably expressing Beclin-1 were established. Autophagic vacuoles in cells were observed with LC3 staining using fluorescence microscopy, and apoptotic cells were detected via flow cytometry. Tumor growth was assessed by subcutaneous inoculation of TNBC cells into BALB/c nude mice. RESULTS: Cantharidin inhibited the proliferation of MDA-MB-231 and MDA-MB-468 cells, and induced cell apoptosis. Cantharidin additionally inhibited the conversion of LC3 I to LC3 II and autophagosome formation by suppressing the expression of Beclin-1. Furthermore, overexpression of Beclin-1 in TNBC cells attenuated the cytotoxicity of cantharidin. In vivo, cantharidin inhibited the growth of MDA-MB-231 and MDA-MB-468 xenografts in nude mice by suppressing autophagy and inducing apoptosis, and Beclin-1 overexpression in TNBC cells reduced the efficacy of cantharidin. CONCLUSIONS: Cantharidin inhibits autophagy by suppressing Beclin-1 expression and inducing apoptosis of TNBC cells in vitro and in vivo, thereby representing a potential strategy for the treatment of TNBC.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Cantaridina/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/metabolismo , Animales , Beclina-1/metabolismo , Línea Celular Tumoral , Humanos , Etiquetado Corte-Fin in Situ , Ratones , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Cell Physiol Biochem ; 44(6): 2395-2406, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29262394

RESUMEN

BACKGROUND/AIMS: Dachengqi decoction (DCQD) is a well-known traditional Chinese herbal drug with strong anti-inflammatory effects. Angiopoietin-1 (Ang-1) plays a vital role in maintaining the stability and integrity of the vascular wall and prevents vascular leakage due to inflammatory mediators. Our previous work found that DCQD protects against pancreatic injury in rats with severe acute pancreatitis (SAP). This study aims to investigate the effects of DCQD on intestinal endothelial damage in both damaged human umbilical vein endothelial cells (HUVECs) and SAP rats. METHODS: HUVECs were randomly divided into four groups: control group, TNF-α group, TNF-α plus Ang-1 group (Ang-1 group), and TNF-α plus DCQD group (DCQD group). Cells were incubated for 6 h, 12 h, and 24 h, before collection. The treatment concentration of DCQD was decided based on a Cell Counting Kit-8 (CCK-8) assay. The monolayer permeability of the HUVECs was assessed by measuring the transendothelial electrical resistance (TEER). Apoptosis was analyzed by flow cytometry. mRNA and protein expression of aquaporin 1 (AQP-1), matrix metalloproteinase 9 (MMP9), and junctional adhesion molecule-C (JAM-C) was evaluated by RT-PCR, immunocytofluorescence, and western blot. Forty male Sprague-Dawley rats were randomized into a control group, SAP group, SAP plus Ang-1 group (Ang-1 group), and SAP plus DCQD group (DCQD group). SAP was induced by intraperitoneal injection of cerulein and lipopolysaccharide (LPS), while the control group received 0.9% saline solution. Evans blue was injected through the penile vein and the rats were then sacrificed 12 h after modeling. Levels of serum amylase, TNF-α, IL-1ß, IL-2, and IL-6 were determined by using ELISA. Intestinal tissue was analysed by histology, and capillary permeability in the tissues was evaluated by Evans blue extravasation assay. Protein and mRNA expression of AQP-1, MMP9, and JAM-C were assessed by immunohistofluorescence, western blot, and RT-PCR. RESULTS: DCQD reduced the permeability of HUVEC induced by TNF-α in vitro. Furthermore, DCQD altered the mRNA and protein levels of JAM-C, MMP9, and AQP-1 in HUVECs after TNF-α induction. SAP intestinal injury induced by cerulein combined with lipopolysaccharides was concomitant with increased expression of JAM-C and MMP9, and reduced expression of AQP-1 in intestinal tissue. Pretreatment with DCQD attenuated SAP intestinal injury and lowered the levels of serum amylase, TNF-α, IL-1ß, IL-2, and IL-6 effectively. Our study demonstrated that DCQD decreased the expression of JAM-C and MMP9 and increased the expression of AQP-1 both in vitro and in vivo. CONCLUSION: DCQD can reduce capillary endothelial damage in acute pancreatitis-associated intestinal injury and the mechanism may be associated with the regulation of endothelial barrier function-associated proteins AQP-1, MMP9, and JAM-C.


Asunto(s)
Antiinflamatorios/uso terapéutico , Células Endoteliales/efectos de los fármacos , Intestinos/efectos de los fármacos , Pancreatitis/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Enfermedad Aguda , Animales , Permeabilidad Capilar/efectos de los fármacos , Citocinas/sangre , Medicamentos Herbarios Chinos/uso terapéutico , Células Endoteliales/patología , Células Endoteliales de la Vena Umbilical Humana , Humanos , Intestinos/irrigación sanguínea , Intestinos/patología , Masculino , Pancreatitis/sangre , Pancreatitis/patología , Ratas , Ratas Sprague-Dawley
18.
Pancreatology ; 16(2): 211-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26804005

RESUMEN

OBJECTIVES: The aim of this study was to evaluate serum procalcitonin (PCT) levels as a prognostic indicator of intestinal barrier function impairment in rats with severe acute pancreatitis (SAP). METHODS: Thirty-six male Sprague Dawley rats were randomly grouped into SAP group (injected sodium taurocholate via biliopancreatic duct), Gln group (gavaged with glutamine after modeling), and control group. Blood, pancreatic, and terminal ileum tissues were obtained from the rats after 6 h of modeling. Serum amylase (Amy) levels were determined using an automatic biochemical detector, while endotoxin (ET), diamine oxidase (DAO), and PCT levels were measured by ELISA test. The pathology of pancreatic and small intestine tissues were observed. PCT protein expression in intestinal tissues were detected by immunohistochemistry and western blot. RESULT: Pancreatic and intestinal injuries in Gln group were significantly lower than SAP group. Serum amylase, DAO, and PCT levels in SAP and Gln groups differed greatly and were significantly higher than control group. Immuno-histochemistry and western blot results showed that PCT protein expression levels in small intestine tissues of SAP group were higher than Gln group and control group. Serum PCT levels had a significant correlation with serum endotoxin, DAO levels and intestinal mucosal injury scores. CONCLUSION: PCT expression in serum and intestinal tissues in SAP rats increased significantly in the early stages of SAP, and was closely related to the onset and degree of intestinal barrier function impairment. Thus, our results showed that measuring serum PCT can be used to predict intestinal mucosal barrier function impairment in SAP rats.


Asunto(s)
Calcitonina/sangre , Mucosa Intestinal/fisiología , Pancreatitis/patología , Animales , Masculino , Pancreatitis/sangre , Ratas , Ratas Sprague-Dawley
19.
Cell Physiol Biochem ; 37(4): 1379-89, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26488574

RESUMEN

BACKGROUND/AIMS: Severe acute pancreatitis (SAP) is a sudden inflammation of the pancreas. The traditional Chinese medicine formula Dachengqi decoction (DCQD) is proven to be beneficial in the comprehensive treatment for pancreatitis patients in clinical practice. However, the molecular mechanism of DCQD on SAP remains unclear. High mobility group box 1(HMGB1) that functions as a damage-associated molecular pattern molecule (DAMP) has attracted much interest. METHODS: In this study, we used lipopolysaccharide (LPS) and cerulein to induce severe acute pancreatitis in C57BL/6 mice with subsequent administration with low, medium and high dose (2.3 g/kg, 7 g/kg and 21 g/kg, respectively) of DCQD. RESULTS: DCQD treatment improved the pathological score and decreased serum amylase and lipase in a dose-dependent manner. In addition, it suppressed the immune cell-induced secretion of HMGB1 and its translocation from the nucleus to the cytoplasm, thus repressing the expression of IL-6 and TNF-α. Further, pretreatment with DCQD decreased responses of TLRs, and suppressed the activation of NF-κB and p38 MAPK pathway. CONCLUSION: Decreasing the secretion of HMGB1 could reduce pro-inflammatory cytokines, which may help cutting down the risks of development from localized pathological changes to a systemic inflammatory response syndrome and even lead to multiple organ failure.


Asunto(s)
Proteína HMGB1/metabolismo , FN-kappa B/metabolismo , Extractos Vegetales/farmacología , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Enfermedad Aguda , Amilasas/sangre , Animales , Ensayo de Inmunoadsorción Enzimática , Interleucina-6/sangre , Lipasa/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Páncreas/metabolismo , Páncreas/patología , Pancreatitis/metabolismo , Pancreatitis/patología , Receptor Toll-Like 4/metabolismo , Receptor Toll-Like 9/metabolismo , Factor de Necrosis Tumoral alfa/sangre
20.
Front Pharmacol ; 15: 1138251, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38708079

RESUMEN

Background and aims: To investigate mechanisms underlying the effects of Da-Cheng-Qi decoction (DCQD) on severe acute pancreatitis (SAP) capillary leakage syndrome. Methods: In this study, a SAP rat model was established using retrograde perfusion of 5% sodium taurocholate into the biliopancreatic duct. The study included three randomized groups: control, SAP (modeling), and DCQD (via gavage at 2 h pre-modeling and 2 and 4 h post-modeling). HPLC was used to analyzed major components of DCQD. Pathological changes and capillary permeability in the rat pancreatic tissues were examined. mRNA levels of claudin 5, occludin, zonula occludin-1 (ZO-1), and junctional adhesion molecules (JAM-C) were assessed using qRT-PCR. Tight junction-associated protein expression was evaluated using immunofluorescence and Western blot analyses. Human umbilical vein endothelial cells (HUVECs) were used to investigate the mechanism m of DCQD. Results: Serum levels of amylase, TNF-α, IL-1ß, IL-2, and IL-6 were higher in the SAP group compared to the DCQD group (p < 0.05). DCQD treatment significantly attenuated rat pancreas damage (p < 0.05) and reduced tissue capillary permeability compared to the SAP group (p < 0.05). Claudin 5, occludin, and ZO-1 expression in the rat tissues was upregulated, but JAM-C was downregulated by DCQD treatment (p < 0.05). HUVEC permeability was improved by DCQD in a dose-time-dependent manner compared to the SAP group (p < 0.05). DCQD also upregulated claudin 5, occludin, and ZO-1 expression in vitro (p < 0.05). Conclusion: DCQD can improve capillary permeability in both in vivo and in vitro models of SAP by upregulating expression of claudin 5, occludin, and ZO-1, but not JAM-C.

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