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1.
Sensors (Basel) ; 24(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38732850

ABSTRACT

Standard beams are mainly used for the calibration of strain sensors using their load reconstruction models. However, as an ill-posed inverse problem, the solution to these models often fails to converge, especially when dealing with dynamic loads of different frequencies. To overcome this problem, a piecewise Tikhonov regularization method (PTR) is proposed to reconstruct dynamic loads. The transfer function matrix is built both using the denoised excitations and the corresponding responses. After singular value decomposition (SVD), the singular values are divided into submatrices of different sizes by utilizing a piecewise function. The regularization parameters are solved by optimizing the piecewise submatrices. The experimental result shows that the MREs of the PTR method are 6.20% at 70 Hz and 5.86% at 80 Hz. The traditional Tikhonov regularization method based on GCV exhibits MREs of 28.44% and 29.61% at frequencies of 70 Hz and 80 Hz, respectively, whereas the L-curve-based approach demonstrates MREs of 29.98% and 18.42% at the same frequencies. Furthermore, the PREs of the PTR method are 3.54% at 70 Hz and 3.73% at 80 Hz. The traditional Tikhonov regularization method based on GCV exhibits PREs of 27.01% and 26.88% at frequencies of 70 Hz and 80 Hz, respectively, whereas the L-curve-based approach demonstrates PREs of 29.50% and 15.56% at the same frequencies. All in all, the method proposed in this paper can be extensively applied to load reconstruction across different frequencies.

2.
Nanomaterials (Basel) ; 14(6)2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38535670

ABSTRACT

The Vth stability and gate reliability of AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (MIS-HEMTs) with alternating O2 plasma treatment were systematically investigated in this article. It was found that the conduction band offset at the Al2O3/AlGaN interface was elevated to 2.4 eV, which contributed to the suppressed gate leakage current. The time-dependent dielectric breakdown (TDDB) test results showed that the ALD-Al2O3 with the alternating O2 plasma treatment had better quality and reliability. The AlGaN/GaN MIS-HEMT with the alternating O2 plasma treatment demonstrated remarkable advantages in higher Vth stability under high-temperature and long-term gate bias stress.

3.
Int J Biol Macromol ; 262(Pt 2): 130148, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38354929

ABSTRACT

Two biobased composite films have been prepared with poly (lactic acid-trimethylene carbonate), polylactic acid and Laponite by solvent evaporation method. The 1H NMR and FTIR spectrums illustrate that P (LA-TMC) polymer is successfully synthesized and designed composite films are produced. Morphometric analyses demonstrate that the roughnesses of the film's surface and cross-section are on the increase with higher PLA and Laponite content. Mechanical performances reveal that the rise in tensile strength and modulus while maintaining excellent elongation at break is mainly due to the increase in the content of polylactic acid and Laponite. By utilizing the nano effect of Laponite, the maximum tensile strength of the composite film reaches 34.59 MPa. Thermal property results illustrate that the Tg and initial decomposition temperature are on the growth with the increase of PLA content. However, it is not significant on the effect of Laponite on the initial decomposition temperature. The water vapor permeability measurements prove that the barrier property of P(LA-TMC)/PLA/Laponite composite film is on the ascent with the Laponite addition. Hydrolytic degradation tests indicate that PLA and Laponite play avital part in accelerating the degradation rate of composite films and alkaline media is superior acidic and neutral conditions.


Subject(s)
Dioxanes , Lactic Acid , Polymers , Silicates , Lactic Acid/chemistry , Polymers/chemistry , Polyesters/chemistry
4.
Article in English | MEDLINE | ID: mdl-37922467

ABSTRACT

Insufficient surface insulation margin is the primary challenge for a 10 kV plus high-voltage semiconductor module. Surface charge accumulation and electric field distortion are the leading causes of surface insulation failure. Power modules restrict leakage loss, so only insulation dielectrics with low surface conductivity can be used. However, low conductivity, accumulated charge dissipation, and distorted electric field optimization have always been contradictory. A potential barrier increase and electron affinity decrease are both less coupled approaches with conductivity, which may have the potential for reducing surface charge accumulation. Here, surface charge accumulation inhibition and local electric field optimization were synchronously realized by tailored coating deposition with colliding plasma jets. This novelty approach leads to a finer interfacial modification of the triple junction and its nearby interfaces. The high-barrier and low-affinity coatings deposited by colliding plasma jets suppress charge injection (electrode-polymer interface) and promote charge dissipation (gas-polymer interface), respectively. At the same time, the small-area semiconductor deposited at the triple junction relieves the distortion of the electric field. In the end, while maintaining a low leakage current, the surface flashover voltages of polytetrafluoroethylene, polyimide, and epoxy packaging polymers are significantly increased by 69.7, 43.2, and 39.6%, respectively. Notably, the normalized leakage loss is less than 3/10,000 of the commercially available SiC module, which vastly differs from the surface insulation improvement strategy that blindly increases surface conductivity. This tailored coating modification strategy provides a new idea for dielectric research. It has reasonable practicability due to fast, cheap, and environmentally friendly colliding plasma jets.

5.
Sensors (Basel) ; 23(19)2023 Oct 02.
Article in English | MEDLINE | ID: mdl-37837052

ABSTRACT

Harmonic distortion is one of the dominant factors limiting the overall signal-to-noise and distortion ratio of seismic-grade sigma-delta MEMS accelerometers. This study investigates harmonic distortion based on the multiple degree-of-freedom model (MDM) established in our previous study. The main advantage of using an MDM is that the effect of finger flexibility on harmonic distortion is considered. Initially, the nonlinear relationship between the input acceleration and output signal is derived using the MDM. Then, harmonic distortion is simulated and described in terms of the nonlinear input-output relationship. It is found that finger flexibility and parasitic capacitance mismatch both decrease harmonic distortion. Finally, the experimental testing of harmonic distortion is implemented. By reducing the finger length to realize a higher stiffness and compensating for the parasitic capacitance mismatch, the total harmonic distortion decreases from -66.8 dB to -86.9 dB.

6.
Nanomaterials (Basel) ; 13(16)2023 Aug 08.
Article in English | MEDLINE | ID: mdl-37630860

ABSTRACT

A novel atomic-level post-etch-surface-reinforcement (PESR) process is developed to recover the p-GaN etching induced damage region for high performance p-GaN gate HEMTs fabrication. This process is composed of a self-limited surface modification step with O2 plasma, following by an oxide removal step with BCl3 plasma. With PESR process, the AlGaN surface morphology after p-GaN etching was comparable to the as-epitaxial level by AFM characterization, and the AlGaN lattice crystallization was also recovered which was measured in a confocal Raman system. The electrical measurement further confirmed the significant improvement of AlGaN surface quality, with one-order of magnitude lower surface leakage in a metal-semiconductor (MS) Schottky-diode and 6 times lower interface density of states (Dit) in a MIS C-V characterization. The XPS analysis of Al2O3/AlGaN showed that the p-GaN etching induced F-byproduct and Ga-oxide was well removed and suppressed by PESR process. Finally, the developed PESR process was successfully integrated in p-GaN gate HEMTs fabrication, and the device performance was significantly enhanced with ~20% lower of on-resistance and ~25% less of current collapse at Vds,Q bias of 40 V, showing great potential of leverage p-GaN gate HEMTs reliability.

7.
Micromachines (Basel) ; 14(8)2023 Jul 29.
Article in English | MEDLINE | ID: mdl-37630059

ABSTRACT

A systematic study of epi-AlGaN/GaN on a SiC substrate was conducted through a comprehensive analysis of material properties and device performance. In this novel epitaxial design, an AlGaN/GaN channel layer was grown directly on the AlN nucleation layer, without the conventional doped thick buffer layer. Compared to the conventional epi-structures on the SiC and Si substrates, the non-buffer epi-AlGaN/GaN structure had a better crystalline quality and surface morphology, with reliable control of growth stress. Hall measurements showed that the novel structure exhibited comparable transport properties to the conventional epi-structure on the SiC substrate, regardless of the buffer layer. Furthermore, almost unchanged carrier distribution from room temperature to 150 °C indicated excellent two-dimensional electron gas (2DEG) confinement due to the pulling effect of the conduction band from the nucleation layer as a back-barrier. High-performance depletion-mode MIS-HEMTs were demonstrated with on-resistance of 5.84 Ω·mm and an output current of 1002 mA/mm. The dynamic characteristics showed a much smaller decrease in the saturation current (only ~7%), with a quiescent drain bias of 40 V, which was strong evidence of less electron trapping owing to the high-quality non-buffer AlGaN/GaN epitaxial growth.

8.
Sensors (Basel) ; 23(12)2023 Jun 07.
Article in English | MEDLINE | ID: mdl-37420559

ABSTRACT

The high-order mechanical resonances of the sensing element in a high-vacuum environment can significantly degrade the noise and distortion performance of seismic-grade sigma-delta MEMS capacitive accelerometers. However, the current modeling approach is unable to evaluate the effects of high-order mechanical resonances. This study proposes a novel multiple-degree-of-freedom (MDOF) model to evaluate the noise and distortion induced by high-order mechanical resonances. Firstly, the MDOF dynamic equations of the sensing element are derived using the principle of modal superposition and Lagrange's equations. Secondly, a fifth-order electromechanical sigma-delta system of the MEMS accelerometer is established in Simulink based on the dynamic equations of the sensing element. Then, the mechanism through which the high-order mechanical resonances degrade the noise and distortion performances is discovered by analyzing the simulated result. Finally, a noise and distortion suppression method is proposed based on the appropriate improvement in high-order natural frequency. The results show that the low-frequency noise drastically decreases from about -120.5 dB to -175.3 dB after the high-order natural frequency increases from about 130 kHz to 455 kHz. The harmonic distortion also reduces significantly.


Subject(s)
Micro-Electrical-Mechanical Systems , Computer Simulation , Records , Vacuum , Accelerometry
9.
Micromachines (Basel) ; 14(7)2023 Jun 21.
Article in English | MEDLINE | ID: mdl-37512589

ABSTRACT

In this work, we demonstrated a low current collapse normally on Al2O3/AlGaN/GaN MIS-HEMT with in situ H-radical surface treatment on AlGaN. The in situ atomic pretreatment was performed in a specially designed chamber prior to the thermal ALD-Al2O3 deposition, which improved the Al2O3/AlGaN interface with Dit of ~2 × 1012 cm-2 eV-1, and thus effectively reduced the current collapse and the dynamic Ron degradation. The devices showed good electrical performance with low Vth hysteresis and peak trans-conductance of 107 mS/mm. Additionally, when the devices operated under 25 °C pulse-mode stress measurement with VDS,Q = 40 V (period of 1 ms, pulse width of 1 µs), the dynamic Ron increase of ~14.1% was achieved.

10.
Micromachines (Basel) ; 14(6)2023 May 23.
Article in English | MEDLINE | ID: mdl-37374685

ABSTRACT

A novel monocrystalline AlN interfacial layer formation method is proposed to improve the device performance of the fully recessed-gate Al2O3/AlN/GaN Metal-Insulator-Semiconductor High Electron Mobility Transistors (MIS-HEMTs), which is achieved by plasma-enhanced atomic layer deposition (PEALD) and in situ N2 plasma annealing (NPA). Compared with the traditional RTA method, the NPA process not only avoids the device damage caused by high temperatures but also obtains a high-quality AlN monocrystalline film that avoids natural oxidation by in situ growth. As a contrast with the conventional PELAD amorphous AlN, C-V results indicated a significantly lower interface density of states (Dit) in a MIS C-V characterization, which could be attributed to the polarization effect induced by the AlN crystal from the X-ray Diffraction (XRD) and Transmission Electron Microscope (TEM) characterizations. The proposed method could reduce the subthreshold swing, and the Al2O3/AlN/GaN MIS-HEMTs were significantly enhanced with ~38% lower on-resistance at Vg = 10 V. What is more, in situ NPA provides a more stable threshold voltage (Vth) after a long gate stress time, and ΔVth is inhibited by about 40 mV under Vg,stress = 10 V for 1000 s, showing great potential for improving Al2O3/AlN/GaN MIS-HEMT gate reliability.

11.
J Funct Biomater ; 13(3)2022 Aug 04.
Article in English | MEDLINE | ID: mdl-35997451

ABSTRACT

Drug-loaded microspheres are an ideal bone tissue delivery material. In this study, a biodegradable Schiff base chitosan-polylactide was used as the encapsulation material to prepare drug-loaded microspheres as biocompatible carriers for controlled vancomycin release. In this regard, Schiff base chitosan was prepared by the Schiff base method, and then different proportions of the Schiff base chitosan-polylactide polymer were prepared by ring-opening polymerization. Drug-loaded microspheres were prepared by the W/O emulsion method, and the polymers and polymer microspheres were characterized and studied by NMR, IR, and antibacterial methods. The drug loading and release rates of microspheres were determined to investigate the drug loading, encapsulation efficiency, and release rate of drug microspheres at different ratios. In this study, different proportions of Schiff base chitosan-polylactic acid materials are successfully prepared, and vancomycin-loaded microspheres are successfully prepared using them as carriers. This study proves that the materials have antibacterial activities against Staphylococcus aureus and Escherichia coli. The particle size of drug-loaded microspheres was below 10 µm, and the particle size decreased with decreasing molecular weight. The obtained results show that 1:100 microspheres have the highest drug-loading and encapsulation efficiencies, the drug-loaded microspheres have no burst release within 24 h, and the release quantity reaches more than 20%. After 30 days of release, the release amounts of 1:10, 1:20, 1:40, 1:60, and 1:100 drug-loaded microspheres were 64.80 ± 0.29%, 54.43 ± 0.54%, 44.60 ± 0.43%, 42.53 ± 0.40% and 69.73 ± 0.45%, respectively, and the release amount of 1:100 was the highest.

12.
Int J Biol Macromol ; 217: 922-930, 2022 Sep 30.
Article in English | MEDLINE | ID: mdl-35908674

ABSTRACT

This study was performed to promote the clinical application of Panax notoginseng saponins (PNS), which present anti-inflammatory and antitumor activities, and provided insights for the preparation of controlled-release dosage forms of traditional Chinese medicine. A series of drug-loaded microspheres with degradable amphiphilic polymer material polyethylene glycol monomethyl ether-polylactic acid (mPEG-PLA) as the carrier was synthesized. The degradation, sustained-release behavior, and biocompatibility of the drug-loaded microspheres were studied through in vitro release, degradation, hemolysis, anticoagulation, and cytotoxicity experiments. The pharmacological activities of the microspheres were studied through anti-inflammatory and antitumor experiments. The results showed that the best carrier material was mPEG2k-PLA (1:9), with an average particle size of 3.47 ± 0.35 µm, a drug load of 5.50 ± 0.28 %, and an encapsulation efficiency of 38.52 ± 1.93 %. This material could be released stably for approximately 24 days and degrade in approximately 60 days. Moreover, the microspheres had good biocompatibility and anti-inflammatory and antitumor activities.


Subject(s)
Panax notoginseng , Saponins , Anti-Inflammatory Agents/pharmacology , Microspheres , Polyesters , Saponins/pharmacology
13.
J Virol ; 96(14): e0047722, 2022 07 27.
Article in English | MEDLINE | ID: mdl-35758666

ABSTRACT

The mechanisms of colostrum-mediated virus transmission are difficult to elucidate because of the absence of experimental animal models and the difficulties in tissue sample collection from mothers in the peripartum period. Porcine epidemic diarrhea virus (PEDV) is a reemerging enteropathogenic coronavirus that has catastrophic impacts on the global pig industry. PEDV primarily infects neonatal piglets by multiple routes, especially 1- to 2-day-old neonatal piglets. Here, our epidemiological investigation and animal challenge experiments revealed that PEDV could be vertically transmitted from sows to neonatal piglets via colostrum, and CD3+ T cells in the colostrum play an important role in this process. The results showed that PEDV colonizing the intestinal epithelial cells (IECs) of orally immunized infected sows could be transferred to CD3+ T cells located just beneath the IECs. Next, PEDV-carrying CD3+ T cells, with the expression of integrin α4ß7 and CCR10, migrate from the intestine to the mammary gland through blood circulation. Arriving in the mammary gland, PEDV-carrying CD3+ T cells could be transported across mammary epithelial cells (MECs) into the lumen (colostrum), as illustrated by an autotransfusion assay and an MECs/T coculture system. The PEDV-carrying CD3+ T cells in colostrum could be interspersed between IECs of neonatal piglets, causing intestinal infection via cell-to-cell contact. Our study demonstrates for the first time that colostrum-derived CD3+ T cells comprise a potential route for the vertical transmission of PEDV. IMPORTANCE The colostrum represents an important infection route for many viruses. Here, we demonstrate the vertical transmission of porcine epidemic diarrhea virus (PEDV) from sows to neonatal piglets via colostrum. PEDV colonizing the intestinal epithelial cells could transfer the virus to CD3+ T cells located in the sow intestine. The PEDV-carrying CD3+ T cells in the sow intestine, with the expression of integrin α4ß7 and CCR10, arrive at the mammary gland through blood circulation and are transported across mammary epithelial cells into the lumen, finally leading to intestinal infection via cell-to-cell contact in neonatal piglets. Our study not only demonstrates an alternative route of PEDV infection but also provides an animal model of vertical transmission of human infectious disease.


Subject(s)
Colostrum , Coronavirus Infections , Infectious Disease Transmission, Vertical , Porcine epidemic diarrhea virus , Swine Diseases , Animals , Animals, Newborn , Colostrum/virology , Coronavirus Infections/transmission , Coronavirus Infections/veterinary , Female , Infectious Disease Transmission, Vertical/veterinary , Porcine epidemic diarrhea virus/physiology , Swine , Swine Diseases/transmission , Swine Diseases/virology , T-Lymphocytes/virology
14.
Br J Cancer ; 127(5): 811-823, 2022 09.
Article in English | MEDLINE | ID: mdl-35637411

ABSTRACT

BACKGROUND: Multiple mechanisms have been proposed that lead to reduced effectiveness of trastuzumab in HER2-positive gastric cancer (GC), yet resistance to trastuzumab remains a challenge in clinics. METHODS: We established trastuzumab-resistant cells and patient-derived xenografts models to measure metabolic levels and vascular density and shape. The HER2-positive GC patient samples were used to determine clinical significance. We also measured protein expression and phosphorylation modifications to determine those alterations related to resistance. In vivo studies combining inhibitor of PFKFB3 with trastuzumab corroborated the in vitro findings. RESULTS: The 6-phosphofructo-2-kinase (PFKFB3)-mediated trastuzumab resistance pathways in HER2-positive GC by activating the glycolytic pathway. We also found vessels are chaotic and destabilised in the tumour during the trastuzumab resistance process. Inhibition of PFKFB3 significantly diminished tumour proliferation and promoted vessel normalisation in the patient-derived xenograft model. Mechanistically, PFKFB3 promoted the secretion of CXCL8 into the tumour microenvironment, and phosphorylated Ser1151 of ERBB2, enhancing the transcription of CXCL8 by activating the PI3K/AKT/NFκB p65 pathway. CONCLUSIONS: Our current findings discover that PFKFB3 inhibitors might be effective tools to overcome adjuvant therapy resistance in HER2-positive GC and reshaping the microenvironment by normalising tumour vessels is a novel strategy to overcome trastuzumab resistance.


Subject(s)
Phosphofructokinase-2 , Stomach Neoplasms , Trastuzumab , Cell Line, Tumor , Drug Resistance, Neoplasm , Female , Humans , Phosphatidylinositol 3-Kinases/metabolism , Phosphofructokinase-2/antagonists & inhibitors , Phosphofructokinase-2/genetics , Phosphofructokinase-2/pharmacology , Receptor, ErbB-2/metabolism , Stomach Neoplasms/drug therapy , Stomach Neoplasms/genetics , Stomach Neoplasms/metabolism , Trastuzumab/pharmacology , Trastuzumab/therapeutic use , Tumor Microenvironment
15.
Micromachines (Basel) ; 13(4)2022 Apr 09.
Article in English | MEDLINE | ID: mdl-35457894

ABSTRACT

A systematic study of the selective etching of p-GaN over AlGaN was carried out using a BCl3/SF6 inductively coupled plasma (ICP) process. Compared to similar chemistry, a record high etch selectivity of 41:1 with a p-GaN etch rate of 3.4 nm/min was realized by optimizing the SF6 concentration, chamber pressure, ICP and bias power. The surface morphology after p-GaN etching was characterized by AFM for both selective and nonselective processes, showing the exposed AlGaN surface RMS values of 0.43 nm and 0.99 nm, respectively. MIS-capacitor devices fabricated on the AlGaN surface with ALD-Al2O3 as the gate dielectric after p-GaN etch showed the significant benefit of BCl3/SF6 selective etch process.

16.
Arch Biochem Biophys ; 722: 109216, 2022 06 15.
Article in English | MEDLINE | ID: mdl-35421356

ABSTRACT

BACKGROUND: FAM98A is a microtubule-associated protein involved in cell proliferation and migration, and is frequently dysregulated in epithelial cancers. But its role in the development of colorectal cancer (CRC) cancer remains unknown. METHODS: Immunohistochemical analysis was performed to examine the expression of FAM98A in CRC samples. We also investigated the effects of abnormal expression on the biological behavior of colorectal cancer cells both in vitro and in vivo. Immunoblotting and immunoprecipitation were used to screen FAM98A-related signalling pathways and downstream factors. RESULTS: FAM98A was upregulated in CRC tissues and CRC cell lines. Overexpression of FAM98A promoted cell proliferation and recovered 5-FU suppressed CRC cell proliferation both in vitro and in vivo. In addition, the Enhanced expression of FAM98A inhibited ferroptosis in CRC cells by activating the translation of xCT in stress granules (SGs). Furthermore, we identified that metformin could reverse FAM98A-mediated 5-FU resistance in CRC cells. CONCLUSIONS: Our results for the first time indicate that FAM98A plays a critical role in promoting CRC progression, which provides a novel target for clinical drug resistance of colorectal cancer. And metformin may sensitize 5-FU in the treatment of colorectal cancer.


Subject(s)
Colorectal Neoplasms , Ferroptosis , Metformin , Cell Line, Tumor , Cell Proliferation , Colorectal Neoplasms/metabolism , Drug Resistance, Neoplasm , Fluorouracil/pharmacology , Gene Expression Regulation, Neoplastic , Humans , Proteins/metabolism
17.
Commun Biol ; 5(1): 252, 2022 03 22.
Article in English | MEDLINE | ID: mdl-35318455

ABSTRACT

The location of intraepithelial lymphocytes (IELs) between epithelial cells provide a first line of immune defense against enteric infection. It is assumed that IELs migrate only along the basement membrane or into the lateral intercellular space (LIS) between epithelial cells. Here, we identify a unique transepithelial migration of porcine IELs as they move to the free surface of the intestinal epithelia. The major causative agent of neonatal diarrhea in piglets, porcine epidemic diarrhea virus (PEDV), increases the number of IELs entering the LIS and free surface of the intestinal epithelia, driven by chemokine CCL2 secreted from virus-infected intestinal epithelial cells. Remarkably, only virus pre-activated IELs inhibits PEDV infection and their antiviral activity depends on the further activation by virus-infected cells. Although high levels of perforin is detected in the co-culture system, the antiviral function of activated IELs is mainly mediated by IFN-γ secretion inducing robust antiviral response in virus-infected cells. Our results uncover a unique migratory behavior of porcine IELs as well as their protective role in the defense against intestinal infection.


Subject(s)
Coronavirus Infections , Intestinal Diseases , Intraepithelial Lymphocytes , Porcine epidemic diarrhea virus , Virus Diseases , Animals , Antiviral Agents/therapeutic use , Coronavirus Infections/drug therapy , Porcine epidemic diarrhea virus/physiology , Swine
18.
J Biomed Mater Res A ; 110(5): 1052-1061, 2022 05.
Article in English | MEDLINE | ID: mdl-34994069

ABSTRACT

Single-walled carbon nanotubes (SWNTs) are cylindrical graphitic helix molecules that exhibit superb mechanical and physical properties. Many polymers, such as polyethylene glycol and glycated chitosan, have been used to modify SWNTs to enhance the stability and biocompatibility of delivery systems; thus, a novel modification for SWNTs with amylose derivatives containing poly(L-lysine) dendrons (ADP@SWNT) is developed. Infrared spectra analysis, 1 H NMR analysis, circular dichroism spectra analysis and thermogravimetric analysis are used to characterize and confirm complex formation. The aqueous dispersion stability, cytotoxicity, gene transfection efficiency and photothermal effect of the complex are studied in vitro and in vivo. Results suggest that the ADP@SWNT complex is successfully synthesized with good water dispersion stability and pDNA transfection capacity. ADP@SWNT/TNFα inhibits tumor growth and metastasis both in vivo and in vitro, and the anti-tumor effect is enhanced by NIR irradiation, suggesting its high potential for application in tumor therapy.


Subject(s)
Colorectal Neoplasms , Nanotubes, Carbon , Adenosine Diphosphate , Amylose , Cations , Colorectal Neoplasms/therapy , Humans , Nanotubes, Carbon/chemistry , Photothermal Therapy
19.
J Reprod Immunol ; 149: 103440, 2022 02.
Article in English | MEDLINE | ID: mdl-34775290

ABSTRACT

Lymphocytes in the colostrum play many important roles during lactation, including protecting newborn piglets against infections. The lymphocytes constantly enter the mammary gland from the mother's bloodstream before and during lactation. However, little is known about the mechanism of transport of maternal lymphocytes across the mammary glands into the milk (lumen). In this study, the maternal lymphocytes were detected in sow colostrum by immunofluorescent staining and fluorescence-activated cell sorting and lymphocytes were observed transmigrating into the breast acinar lumen. Furthermore, immunohistochemical staining revealed that CD3+ T, γδ+ T, and IgA+ B cells were primarily located at the base area of the mammary gland. Meanwhile, more lactating alveoli and blood capillaries were distributed in this area. Finally, a mammary epithelial cell (EpH4-Ev)/T cell co-culture system was established to explore the mechanism of lymphocyte transmigration across the mammary epithelial cells. The expression of CCL2 and CCL28 in EpH4-Ev cells, which facilitated the transmigration of lymphocytes, significantly increased in the presence of prolactin. Our results provide a better understanding of the concept of lactogenic immunity and pave the way for vaccination strategies for the induction of lactogenic immunity in pregnant swine.


Subject(s)
Cell Movement , Lymphocytes , Milk , Transendothelial and Transepithelial Migration , Animals , B-Lymphocytes/immunology , Epithelial Cells/metabolism , Female , Immunity, Maternally-Acquired/drug effects , Lactation/immunology , Mammary Glands, Animal/metabolism , Milk/cytology , Pregnancy , Prolactin/metabolism , Swine
20.
Cells ; 10(9)2021 08 31.
Article in English | MEDLINE | ID: mdl-34571913

ABSTRACT

Immunological memory is a cardinal feature of the immune system. The intestinal mucosa is the primary exposure and entry site of infectious organisms. For an effective and long-lasting safeguard, a robust immune memory system is required, especially by the mucosal immunity. It is well known that tissue-resident memory T cells (Trms) provide a first response against infections reencountered at mucosal tissues surfaces, where they accelerate pathogen clearance. However, their function in intestinal immunization remains to be investigated. Here, we report enhanced local mucosal and systemic immune responses through oral administration of H9N2 influenza whole inactivated virus (H9N2 WIV) plus Bacillus subtilis spores. Subsequently, H9N2 WIV plus spores led to the generation of CD103+ CD69+ Trms, which were independent of circulating T cells during the immune period. Meanwhile, we also found that Bacillus subtilis spores could stimulate Acrp30 expression in 3T3-L1 adipocytes. Moreover, spore-stimulated adipocyte supernatant also upregulated the expression of intercellular adhesion molecule-1 (ICAM1) in dendritic cells (DCs). Furthermore, the proportion of HA-tetramer+ cells was severely curtailed upon suppressed ICAM1 expression, which also depended on HA-loaded DCs. Taken together, our data demonstrated that spore-promoted H9N2 WIV induced an immune response by enhancing Trms populations, which were associated with the activation of ICAM1 in DCs.


Subject(s)
Bacillus subtilis/immunology , Dendritic Cells/immunology , Immunologic Memory/immunology , Intercellular Adhesion Molecule-1/metabolism , Intestinal Mucosa/immunology , Spores, Bacterial/immunology , T-Lymphocytes/immunology , Adjuvants, Immunologic , Animals , Antibodies, Viral/immunology , Immunization , Influenza A Virus, H9N2 Subtype/immunology , Intercellular Adhesion Molecule-1/genetics , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL
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