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1.
Nature ; 626(8001): 990-998, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38383782

RESUMEN

Electrode-based electrical stimulation underpins several clinical bioelectronic devices, including deep-brain stimulators1,2 and cardiac pacemakers3. However, leadless multisite stimulation is constrained by the technical difficulties and spatial-access limitations of electrode arrays. Optogenetics offers optically controlled random access with high spatiotemporal capabilities, but clinical translation poses challenges4-6. Here we show tunable spatiotemporal photostimulation of cardiac systems using a non-genetic platform based on semiconductor-enabled biomodulation interfaces. Through spatiotemporal profiling of photoelectrochemical currents, we assess the magnitude, precision, accuracy and resolution of photostimulation in four leadless silicon-based monolithic photoelectrochemical devices. We demonstrate the optoelectronic capabilities of the devices through optical overdrive pacing of cultured cardiomyocytes (CMs) targeting several regions and spatial extents, isolated rat hearts in a Langendorff apparatus, in vivo rat hearts in an ischaemia model and an in vivo mouse heart model with transthoracic optical pacing. We also perform the first, to our knowledge, optical override pacing and multisite pacing of a pig heart in vivo. Our systems are readily adaptable for minimally invasive clinical procedures using our custom endoscopic delivery device, with which we demonstrate closed-thoracic operations and endoscopic optical stimulation. Our results indicate the clinical potential of the leadless, lightweight and multisite photostimulation platform as a pacemaker in cardiac resynchronization therapy (CRT), in which lead-placement complications are common.


Asunto(s)
Terapia de Resincronización Cardíaca , Diseño de Equipo , Marcapaso Artificial , Silicio , Animales , Ratones , Ratas , Terapia de Resincronización Cardíaca/métodos , Endoscopía , Corazón , Procedimientos Quirúrgicos Mínimamente Invasivos , Isquemia Miocárdica/cirugía , Isquemia Miocárdica/terapia , Miocitos Cardíacos , Semiconductores , Porcinos , Modelos Animales
2.
Acc Chem Res ; 57(9): 1398-1410, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38652467

RESUMEN

Electrical neuromodulation has achieved significant translational advancements, including the development of deep brain stimulators for managing neural disorders and vagus nerve stimulators for seizure treatment. Optoelectronics, in contrast to wired electrical systems, offers the leadless feature that guides multisite and high spatiotemporal neural system targeting, ensuring high specificity and precision in translational therapies known as "photoelectroceuticals". This Account provides a concise overview of developments in novel optoelectronic nanomaterials that are engineered through innovative molecular, chemical, and nanostructure designs to facilitate neural interfacing with high efficiency and minimally invasive implantation.This Account outlines the progress made both within our laboratory and across the broader scientific community, with particular attention to implications in materials innovation strategies, studying bioelectrical activation with spatiotemporal methods, and applications in regenerative medicine. In materials innovation, we highlight a nongenetic, biocompatible, and minimally invasive approach for neuromodulation that spans various length scales, from single neurons to nerve tissues using nanosized particles and monolithic membranes. Furthermore, our discussion exposes the critical unresolved questions in the field, including mechanisms of interaction at the nanobio interface, the precision of cellular or tissue targeting, and integration into existing neural networks with high spatiotemporal modulation. In addition, we present the challenges and pressing needs for long-term stability and biocompatibility, scalability for clinical applications, and the development of noninvasive monitoring and control systems.In addressing the existing challenges in the field of nanobio interfaces, particularly for neural applications, we envisage promising strategic directions that could significantly advance this burgeoning domain. This involves a deeper theoretical understanding of nanobiointerfaces, where simulations and experimental validations on how nanomaterials interact spatiotemporally with biological systems are crucial. The development of more durable materials is vital for prolonged applications in dynamic neural interfaces, and the ability to manipulate neural activity with high specificity and spatial resolution, paves the way for targeting individual neurons or specific neural circuits. Additionally, integrating these interfaces with advanced control systems, possibly leveraging artificial intelligence and machine learning algorithms and programming dynamically responsive materials designs, could significantly ease the implementation of stimulation and recording. These innovations hold the potential to introduce novel treatment modalities for a wide range of neurological and systemic disorders.


Asunto(s)
Nanoestructuras , Humanos , Nanoestructuras/química , Nanotecnología/métodos , Animales , Electrónica
3.
Physiol Plant ; 176(3): e14323, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38695188

RESUMEN

Tomatoes are frequently challenged by various pathogens, among which Phytophthora capsici (P. capsici) is a destructive soil-borne pathogen that seriously threatens the safe production of tomatoes. Plant growth-promoting rhizobacteria (PGPR) positively induced plant resistance against multiple pathogens. However, little is known about the role and regulatory mechanism of PGPR in tomato resistance to P. capsici. Here, we identified a new strain Serratia plymuthica (S. plymuthica), HK9-3, which has a significant antibacterial effect on P. capsici infection. Meanwhile, stable colonization in roots by HK9-3, even under P. capsici infection, improved tomato growth parameters, root system architecture, photosynthetic capacity, and boosted biomass. Importantly, HK9-3 colonization significantly alleviated the damage caused by P. capsici infection through enhancing ROS scavenger ability and inducing antioxidant defense system and pathogenesis-related (PR) proteins in leaves, as evidenced by elevating the activities of peroxidase (POD), superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), and chitinase, ß-1,3-glucanase, and increasing the transcripts of POD, SOD, CAT, APX1, PAL1, PAL2, PAL5, PPO2, CHI17 and ß-1,3-glucanase genes. Notably, HK9-3 colonization not only effectively improved soil microecology and soil fertility, but also significantly enhanced fruit yield by 44.6% and improved quality. Our study presents HK9-3 as a promising and effective solution for controlling P. capsici infection in tomato cultivation while simultaneously promoting plant growth and increasing yield, which may have implications for P. capsici control in vegetable production.


Asunto(s)
Resistencia a la Enfermedad , Phytophthora , Enfermedades de las Plantas , Rizosfera , Serratia , Solanum lycopersicum , Solanum lycopersicum/microbiología , Solanum lycopersicum/fisiología , Solanum lycopersicum/genética , Phytophthora/fisiología , Serratia/fisiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Antioxidantes/metabolismo , Raíces de Plantas/microbiología , Raíces de Plantas/fisiología
4.
Nanotechnology ; 35(29)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38154130

RESUMEN

We successfully fabricated two-dimensional metallic CoBi nanoislands on SrTiO3(001) substrate by molecular beam epitaxy, and systematically investigated their electronic structures by scanning tunneling microscopy and spectroscopyin situat 4.2 K. Coulomb blockade and Coulomb staircases with discrete and well-separated levels are observed for the individual nanoisland, which is attributed to single-electron tunneling via two tunnel junction barriers. They are in excellent agreement with the simulations based on orthodox theory. Furthermore, we demonstrated that the Coulomb blockade becomes weaker with increasing temperature and almost disappears at ∼22 K in our variable temperature experiment, and its full-width at half-maximum of dI/dVpeaks with temperature is ∼6 mV. Our results provide a new platform for designing single-electron transistors that have potential applications in future microelectronics.

5.
Food Microbiol ; 120: 104482, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38431313

RESUMEN

Hafnia paralvei, a Gram-negative foodborne pathogen, is found ubiquitously in various aquatic animals and seafoods, which can form biofilm as a dominant virulence factor that contributes to its pathogenesis. However, the biofilm formation mechanism of H. paralvei and its effect on food spoilage has not been fully characterized. Here we show that biofilm formation, is regulated by c-di-GMP which mediated by bcsB, can increase the spoilage ability of H. paralvei. We found that GTP was added exogenously to enhance the synthesis of c-di-GMP, which further promoted biofilm formation. The gene dgcC, one of 11 genes encoding GGDEF domain-containing proteins in H. paralvei, was significantly upregulated with GTP as substrate. The upregulation of dgcC contributes to a significant increase of c-di-GMP and the formation of biofilm. In addition, the overexpression of dgcC induced upregulation of bcsB, a reported effector protein encoding gene, which was further demonstrated that overexpression of bcsB can encourage the synthesis of bacterial cellulose and biofilm formation. The effect of biofilm formation induced by c-di-GMP on spoilage of Yellow River carp (Cyprinus carpio) was evaluated by sensory evaluation, the total viable count, and the total volatile basic nitrogen, which showed that biofilm formation can significantly increase the spoilage ability of H. paralvei on C. carpio. Our findings provide the regulation of c-di-GMP on expression of bcsB, that can contribute to biofilm formation and spoilage ability of H. paralvei, which is favor to understanding the pathogenesis of Hafnia paralvei and its role in food spoilage.


Asunto(s)
Proteínas Bacterianas , Carpas , GMP Cíclico/análogos & derivados , Hafnia , Animales , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Expresión Génica , Alimentos Marinos , Biopelículas , Guanosina Trifosfato
6.
Sensors (Basel) ; 24(13)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-39001111

RESUMEN

Space targets move in orbit at a very high speed, so in order to obtain high-quality imaging, high-speed motion compensation (HSMC) and translational motion compensation (TMC) are required. HSMC and TMC are usually adjacent, and the residual error of HSMC will reduce the accuracy of TMC. At the same time, under the condition of low signal-to-noise ratio (SNR), the accuracy of HSMC and TMC will also decrease, which brings challenges to high-quality ISAR imaging. Therefore, this paper proposes a joint ISAR motion compensation algorithm based on entropy minimization under low-SNR conditions. Firstly, the motion of the space target is analyzed, and the echo signal model is obtained. Then, the motion of the space target is modeled as a high-order polynomial, and a parameterized joint compensation model of high-speed motion and translational motion is established. Finally, taking the image entropy after joint motion compensation as the objective function, the red-tailed hawk-Nelder-Mead (RTH-NM) algorithm is used to estimate the target motion parameters, and the joint compensation is carried out. The experimental results of simulation data and real data verify the effectiveness and robustness of the proposed algorithm.

7.
J Transl Med ; 21(1): 343, 2023 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-37221577

RESUMEN

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is a highly invasive and metastatic subtype of kidney malignancy and is correlated with metabolic reprogramming for adaptation to the tumor microenvironment comprising infiltrated immune cells and immunomodulatory molecules. The role of immune cells in the tumor microenvironment (TME) and their association with abnormal fatty acids metabolism in ccRCC remains poorly understood. METHOD: RNA-seq and clinical data of KIRC from The Cancer Genome Atlas (TCGA) and E-MTAB-1980 from the ArrayExpress dataset. The Nivolumab group and Everolimus group of the CheckMate 025 study, the Atezolizumab arm of IMmotion150 and the Atezolizumab plus Bevacizumab group of IMmotion151 cohort were obtained for subsequent analysis. After differential expression genes identification, the signature was constructed through univariate Cox proportional hazard regression and simultaneously the least absolute shrinkage and selection operator (Lasso) analysis and the predictive performance of our signature was assessed by using receiver operating characteristic (ROC), Kaplan-Meier (KM) survival analysis, nomogram, drug sensitivity analysis, immunotherapeutic effect analysis and enrichment analysis. Immunohistochemistry (IHC), qPCR and western blot were performed to measure related mRNA or protein expression. Biological features were evaluated by wound healing, cell migration and invasion assays and colony formation test and analyzed using coculture assay and flow cytometry. RESULTS: Twenty fatty acids metabolism-related mRNA signatures were constructed in TCGA and possessed a strong predictive performance demonstrated through time-dependent ROC and KM survival analysis. Notably, the high-risk group exhibited an impaired response to anti-PD-1/PD-L1 (Programmed death-1 receptor/Programmed death-1 receptor-ligand) therapy compared to the low-risk group. The overall levels of the immune score were higher in the high-risk group. Additionally, drug sensitivity analysis observed that the model could effectively predict efficacy and sensitivity to chemotherapy. Enrichment analysis revealed that the IL6-JAK-STAT3 signaling pathway was a major pathway. IL4I1 could promote ccRCC cells' malignant features through JAK1/STAT3 signaling pathway and M2-like macrophage polarization. CONCLUSION: The study elucidates that targeting fatty acids metabolism can affect the therapeutic effect of PD-1/PD-L1 in TME and related signal pathways. The model can effectively predict the response to several treatment options, underscoring its potential clinical utility.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Antígeno B7-H1 , Microambiente Tumoral , Ácidos Grasos , L-Aminoácido Oxidasa
8.
Nat Mater ; 21(6): 647-655, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35618824

RESUMEN

Homo- and heterojunctions play essential roles in semiconductor-based devices such as field-effect transistors, solar cells, photodetectors and light-emitting diodes. Semiconductor junctions have been recently used to optically trigger biological modulation via photovoltaic or photoelectrochemical mechanisms. The creation of heterojunctions typically involves materials with different doping or composition, which leads to high cost, complex fabrications and potential side effects at biointerfaces. Here we show that a porosity-based heterojunction, a largely overlooked system in materials science, can yield an efficient photoelectrochemical response from the semiconductor surface. Using self-limiting stain etching, we create a nanoporous/non-porous, soft-hard heterojunction in p-type silicon within seconds under ambient conditions. Upon surface oxidation, the heterojunction yields a strong photoelectrochemical response in saline. Without any interconnects or metal modifications, the heterojunction enables efficient non-genetic optoelectronic stimulation of isolated rat hearts ex vivo and sciatic nerves in vivo with optical power comparable to optogenetics, and with near-infrared capabilities.


Asunto(s)
Ciencia de los Materiales , Semiconductores , Porosidad
9.
Br J Nutr ; 130(10): 1678-1688, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-36999370

RESUMEN

The current study aims to confirm the positive effects of dietary nano-Se on nutrients deposition and muscle fibre formation in grass carp fed with high-fat diet (HFD) before overwintering and to reveal its possible molecular mechanism. The lipid deposition, protein synthesis and muscle fibre formation in grass carp fed with regular diet (RD), HFD or HFD supplemented with nano-Se (0·3 or 0·6 mg/kg) for 60 d were tested. Results show that nano-Se significantly reduced lipid content, dripping loss and fibre diameter (P < 0·05), but increased protein content, post-mortem pH24 h and muscle fibre density (P < 0·05) in muscle of grass carp fed with HFD. Notably, dietary nano-Se decreased lipid deposition in the muscle by regulating amp-activated protein kinase activity and increased protein synthesis and fibre formation in muscle by activating target of rapamycin and myogenic determining factors pathways. In summary, dietary nano-Se can regulate the nutrients deposition and muscle fibre formation in grass carp fed with HFD, which exhibit potential benefit for improving flesh quality of grass carp fed with HFD.


Asunto(s)
Carpas , Dieta Alta en Grasa , Animales , Dieta Alta en Grasa/efectos adversos , Dieta , Suplementos Dietéticos , Lípidos , Fibras Musculares Esqueléticas , Alimentación Animal/análisis
10.
Int J Med Sci ; 20(4): 505-519, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37057212

RESUMEN

Background and aims: Macrophages play a critical role in the development of liver diseases. As an NAD+-dependent histone deacetylase, SIRT1 inhibits liver inflammation and fibrosis, but the mechanisms are not fully understood. Our aim was to investigate the molecular mechanism of SIRT1 in macrophages in liver inflammation and fibrosis. Methods: We employed the CCl4-induced hepatic fibrosis rat models and cultured murine macrophages RAW 264.7 in vitro to explore the anti-fibrosis effect of SIRT1. The content of cytokines was measured with ELISA. The expression of proteins associated with the NF-κB /NLPR3 signaling pathway was detected by Western blot, co-immunoprecipitation, and immunofluorescence. SIRT1, NF-κB, and NLRP3 genes were knocked down in RAW 264.7 cells by small interfering RNA (siRNA) transfection. Results: The expression of NF-κB p65, NLRP3, α-SMA, and iNOS increased in liver tissue, with high plasma LPS level and low expression of SIRT1 in CCl4-induced rat models. Overexpressing SIRT1 could inhibit these protein levels, decrease plasma LPS level, and attenuate liver injury and fibrosis. In vitro, LPS induced cytomorphology changes and up-regulated NF-κB/NLRP3 pathway, with the low expression of SIRT1 in RAW 264.7; meanwhile, the secretion of inflammatory factors increased. Nevertheless, knockdown of NF-κB or NLRP3 and activation of SIRT1 inhibited inflammation of macrophages; inhibition or knockdown of SIRT1 enhanced macrophage inflammation. Furthermore, activation of SIRT1 could inhibit LPS-treated macrophages from activating hepatic stellate cells (HSCs). Conclusions: Activating SIRT1 inhibits the inflammation in macrophages by down-regulating NLRP3 pathway through deacetylating NF-κB p65, which in turn inhibits the activation of HSCs to alleviate hepatic inflammation and fibrosis.


Asunto(s)
FN-kappa B , Proteína con Dominio Pirina 3 de la Familia NLR , Ratas , Ratones , Animales , FN-kappa B/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Sirtuina 1/genética , Sirtuina 1/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Inflamación/metabolismo , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , ARN Interferente Pequeño/metabolismo
11.
BMC Musculoskelet Disord ; 24(1): 151, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36849968

RESUMEN

BACKGROUND: 3D printing technology has become a research hotspot in the field of scientific research because of its personalized customization, maneuverability and the ability to achieve multiple material fabrications. The focus of this study is to use 3D printing technology to customize personalized poly L-lactic acid (PLLA) porous screws in orthopedic plants and to explore its effect on tendon-bone healing after anterior cruciate ligament (ACL) reconstruction. METHODS: Preparation of PLLA porous screws with good orthogonal pore structure by 3D printer. The hydroxyapatite (HA) was adsorbed on porous screws by electrostatic layer-by-layer self-assembly (ELSA) technology, and PLLA-HA porous screws were prepared. The surface and spatial morphology of the modified screws were observed by scanning electron microscopy (SEM). The porosity of porous screw was measured by liquid displacement method. Thirty New Zealand male white rabbits were divided into two groups according to simple randomization. Autologous tendon was used for right ACL reconstruction, and porous screws were inserted into the femoral tunnel to fix the transplanted tendon. PLLA group was fixed with porous screws, PLLA-HA group was fixed with HA modified porous screws. At 6 weeks and 12 weeks after surgery, 5 animals in each group were sacrificed randomly for histological examination. The remaining 5 animals in each group underwent Micro-CT and biomechanical tests. RESULTS: The pores of PLLA porous screws prepared by 3D printer were uniformly distributed and connected with each other, which meet the experimental requirements. HA was evenly distributed in the porous screw by ELSA technique. Histology showed that compared with PLLA group, mature bone trabeculae were integrated with grafted tendons in PLLA-HA group. Micro-CT showed that the bone formation index of PLLA-HA group was better than that of PLLA group. The new bone was uniformly distributed in the bone tunnel along the screw channel. Biomechanical experiments showed that the failure load and stiffness of PLLA-HA group were significantly higher than those of PLLA group. CONCLUSIONS: The 3D printed PLLA porous screw modified by HA can not only fix the grafted tendons, but also increase the inductivity of bone, promote bone growth in the bone tunnel and promote bone integration at the tendon-bone interface. The PLLA-HA porous screw is likely to be used in clinic in the future.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior , Animales , Conejos , Ligamento Cruzado Anterior/cirugía , Tornillos Óseos , Durapatita , Articulación de la Rodilla , Ácido Láctico , Porosidad
12.
Sensors (Basel) ; 23(23)2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38067917

RESUMEN

This research paper introduces an innovative technique for measuring displacement using auxetic tubular structure (ATS). The proposed displacement measurement method is based on tubular structures with a negative Poisson's ratio. It capitalizes on the underlying principle that the elastic deformation-induced change in transmittance of the ATS can be translated into a corresponding modification in the output current of the solar cell. This method allows for the conversion of the variation in light transmission into a corresponding variation in output voltage. The construction of the ATS can be achieved through 3D-printing technology, enhancing the accessibility of displacement measurement and design flexibility. The experimental results demonstrate that the proposed measurement method exhibits a linear error of less than 8% without any subsequent signal processing and achieves a sensitivity of 0.011 V/mm without signal amplification. Furthermore, experimental results also show that the proposed method has good repeatability and can maintain a high level of reliability and sensitivity when using different measurement devices. This confirms the effectiveness and feasibility of the proposed method, showing a favorable linear relationship between the input and output of the measurement system with an acceptable sensitivity, repeatability, and reliability.

13.
BMC Genomics ; 23(1): 267, 2022 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35387588

RESUMEN

BACKGROUND: The growth and development of muscle stem cells (MuSCs) are significant events known to affect muscle plasticity, disease, meat production, and meat quality, which involves the types and functions of mRNA and non-coding RNA. Here, MuSCs were cultured from Guangxi fetal cattle. RNA sequencing was used to analyze the RNA expression of mRNA and non-coding RNAs during the cell proliferation and differentiation phases. RESULTS: Two thousand one hundred forty-eight mRNAs and 888 non-coding RNAs were differentially expressed between cell proliferation and differentiation phases, including 113 miRNAs, 662 lncRNAs, and 113 circRNAs. RT-qPCR verified the differential expression levels of mRNAs and non-coding RNAs, and the differentially expressed circUBE2Q2 was subsequently characterized. Expression profile analysis revealed that circUBE2Q2 was abundant in muscle tissues and intramuscular fat. The expression of cricUBE2Q2 was also significantly upregulated during MuSCs myogenic differentiation and SVFs adipogenic differentiation and decreased with age in cattle muscle tissue. Finally, the molecular mechanism of circUBE2Q2 regulating MuSCs function that affects skeletal muscle development was investigated. The results showed that circUBE2Q2 could serve as a sponge for miR-133a, significantly promoting differentiation and apoptosis of cultured MuSCs, and inhibiting proliferation of MuSCs. CONCLUSIONS: CircUBE2Q2 is associated with muscle growth and development and induces MuSCs myogenic differentiation through sponging miR-133a. This study will provide new clues for the mechanisms by which mRNAs and non-coding RNAs regulate skeletal muscle growth and development, affecting muscle quality and diseases.


Asunto(s)
MicroARNs , Desarrollo de Músculos , Animales , Bovinos , Diferenciación Celular/genética , China , MicroARNs/genética , MicroARNs/metabolismo , Desarrollo de Músculos/genética , Músculo Esquelético/metabolismo , Músculos/metabolismo , Mioblastos/metabolismo , ARN Mensajero/genética
14.
J Am Chem Soc ; 144(38): 17604-17610, 2022 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-36102900

RESUMEN

Chloride oxidation has tremendous utility in the burgeoning field of chlorine-mediated C-H activation, yet it remains a challenging process to initiate with light because of the exceedingly positive one-electron reduction potential, E° (Cl•/-), beyond most common transition-metal photooxidants. Herein, two photocatalytic chloride oxidation pathways that involve either one- or consecutive two-photon excitation of N-phenylphenothiazine (PTH) are presented. The one-photon pathway generates PTH•+ by oxidative quenching that subsequently disproportionates to yield PTH2+ that oxidizes chloride; this pathway is also accessed by the electrochemical oxidation of PTH. The two-photon pathway, which proceeded through the radical cation excited state, 2PTH•+*, was of particular interest as this super-photooxidant was capable of directly oxidizing chloride to chlorine atoms. Laser flash photolysis revealed that the photooxidation by the doublet excited state proceeded on a subnanosecond timescale through a static quenching mechanism with an ion-pairing equilibrium constant of 0.36 M-1. The PTH photoredox chemistry was quantified spectroscopically on nanosecond and longer time scales, and chloride oxidation chemistry was revealed by reactivity studies with model organic substrates. One- and two-photon excitation of PTH enabled chlorination of unactivated C(sp3)-H bonds of organic compounds such as cyclohexane with substantial yield enhancement observed from inclusion of the second excitation wavelength. This study provides new mechanistic insights into chloride oxidation catalyzed by an inexpensive and commercially available organic photooxidant.


Asunto(s)
Cloruros , Cloro , Cationes/química , Cloruros/química , Cloro/química , Ciclohexanos , Oxidación-Reducción , Fotólisis
15.
J Am Chem Soc ; 144(16): 7043-7047, 2022 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-35271254

RESUMEN

Photoexcitation of molecular radicals can produce strong reducing agents; however, the limited lifetimes of the doublet excited states preclude many applications. Herein, we propose and demonstrate a general strategy to translate a highly energetic electron from a doublet excited state to a ZrO2 insulator, thereby increasing the lifetime by about 6 orders of magnitude while maintaining a reducing potential less than -2.4 V vs SCE. Specifically, red light excitation of a salicylic acid modified perylene diimide radical anion PDI•- anchored to a ZrO2 insulator yields a ZrO2(e-)|PDI charge separated state with an ∼10 µs lifetime in 23% yield. The ZrO2(e-)s were shown to drive CO2 → CO reduction with a Re catalyst present in micromolar concentrations. More broadly, this strategy provides new opportunities to reduce important reagents and catalysts at low concentrations through diffusional electron transfer.


Asunto(s)
Luz , Sustancias Reductoras , Catálisis , Transporte de Electrón , Electrones
16.
Immunol Invest ; 51(2): 411-424, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33078652

RESUMEN

BACKGROUND: Influenza A viruses (IAVs) induce acute respiratory disease and cause severe epidemics and pandemics. Since IAVs exhibit antigenic variation and genome reassortment, the development of broad-spectrum influenza vaccines is crucial. The stem of the hemagglutinin (HA) is highly conserved across IAV strains and thus has been explored in broad-spectrum influenza vaccine studies. The present study aimed to identify viral epitopes capable of eliciting effective host immune responses, which can be explored for the development of broad-spectrum non-strain specific prophylactic options against IAV. METHODS: In this study, a series of conserved linear sequences from the HA stem of IAV (H1N1) was recognized by sequence alignment and B/T-cell epitope prediction after being chemically coupled to the Keyhole Limpet Hemocyanin (KLH) protein. The predicted linear epitopes were identified by enzyme-linked immunosorbent assay (ELISA) after animal immunization and then fused with ferritin carriers. RESULTS: Three predicted linear epitopes with relatively strong immunogenicity, P3, P6 and P8 were fused with ferritin carriers P3F, P6F and P8F, respectively to further improve their immunogenicity. Antibody titre of the sera of mice immunized with the recombinant immunogens revealed the elicitation of specific antibody-binding activities by the identified sequences. While hemagglutinin-inhibition activities were not detected in the antisera, neutralizing antibodies against the H1 and H3 virus subtypes were detected by the microneutralization assay. CONCLUSION: The linear epitopes fused with ferritin identified in this study can lay the foundation for future advancements in development of broad-spectrum subunit vaccine against IAV (H1N1), and give rise to the potential future applicability of ferritin-based antigen delivery nanoplatforms.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Infecciones por Orthomyxoviridae , Animales , Anticuerpos Antivirales , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Hemaglutininas/genética , Humanos , Subtipo H1N1 del Virus de la Influenza A/genética , Gripe Humana/prevención & control , Ratones , Infecciones por Orthomyxoviridae/prevención & control , Péptidos/genética
17.
Genomics ; 113(4): 2108-2121, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33964421

RESUMEN

Tomato is more prone to Tuta absoluta invasion and damages as compared to other host plants but the mechanism behind this preference has not been elucidated. Here, two contrasting host preference plants, tomato and eggplant, were used to investigate biochemical and transcriptomic modifications induced by T. absoluta infestation. Biochemical analysis at 0-72 h post T. absoluta infestation revealed significantly reduced concentrations of amino acid, fructose, sucrose, jasmonic acid, salicylic acid, and total phenols in tomato compared to eggplant, mainly at 48 h post T. absoluta infestation. Transcriptome analysis showed higher transcript changes in infested eggplant than tomato. Signaling genes had significant contributions to mediate plant immunity against T. absoluta, specifically genes associated with salicylic acid in eggplant. Genes from PR1b1, NPR1, NPR3, MAPKs, and ANP1 families play important roles to mitigate T. absoluta infestation. Our results will facilitate the development of control strategies against T. absoluta for sustainable tomato production.


Asunto(s)
Mariposas Nocturnas , Solanum lycopersicum , Solanum melongena , Animales , Perfilación de la Expresión Génica , Humanos , Solanum lycopersicum/genética , Mariposas Nocturnas/fisiología , Solanum melongena/genética , Transcriptoma
18.
Genomics ; 113(2): 740-754, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33516849

RESUMEN

Clear-cell renal cell carcinoma (ccRCC) carries a variable prognosis. Prognostic biomarkers can stratify patients according to risk, and can provide crucial information for clinical decision-making. We screened for an autophagy-related long non-coding lncRNA (lncRNA) signature to improve postoperative risk stratification in The Cancer Genome Atlas (TCGA) database. We confirmed this model in ICGC and SYSU cohorts as a significant and independent prognostic signature. Western blotting, autophagic-flux assay and transmission electron microscopy were used to verify that regulation of expression of 8 lncRNAs related to autophagy affected changes in autophagic flow in vitro. Our data suggest that 8-lncRNA signature related to autophagy is a promising prognostic tool in predicting the survival of patients with ccRCC. Combination of this signature with clinical and pathologic parameters could aid accurate risk assessment to guide clinical management, and this 8-lncRNAs signature related to autophagy may serve as a therapeutic target.


Asunto(s)
Autofagia/genética , Biomarcadores de Tumor/genética , Carcinoma de Células Renales/genética , Neoplasias Renales/genética , ARN Largo no Codificante/genética , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Humanos , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , ARN Largo no Codificante/metabolismo
19.
Fish Physiol Biochem ; 48(6): 1717-1735, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35879492

RESUMEN

The purpose of this study was to explore the beneficial effects of sea buckthorn polysaccharide (SP) on lipid metabolism, liver, and intestinal health in zebrafish fed with high-fat diet (HFD). The zebrafish were fed with regular diet (RD), HFD, and HFD supplemented with 2 g/kg (HFD_2SP) and 4 g/kg (HFD_4SP) of SP, respectively. Growth, serum biochemistry, histopathology, expression of genes involved in lipid metabolism, inflammation, oxidative stress and tight junction, and changes in intestinal microbiota were detected. Results showed that adding 2 and 4 g/kg of SP in the HFD significantly improved the survival rate of zebrafish; reduced the levels of serum triglyceride (TG), total cholesterol (TC), aspartate aminotransferase (AST), and alanine transaminase (ALT); and alleviated the lipid accumulation in the liver of zebrafish. Furthermore, SP significantly enhanced the antioxidant capacity of liver and intestine by up-regulating the expression of Nrf2 and Cu/Zn-SOD and alleviated liver and intestinal inflammation induced by HFD through up-regulating the expression of TGF-ß1 and suppressing the expression of P38MAPK, IL-8, and IL-1ß. Especially, dietary SP normalized intestinal microbiota imbalance caused by HFD and inhibited the proliferation of harmful bacteria, i.e., Mycobacterium, but promoted the proliferation of intestinal beneficial bacteria, i.e., Cetobacterium. In summary, 2 and 4 g/kg of dietary SP significantly reduced lipid accumulation, alleviated inflammation and oxidative stress, and normalized the imbalance of intestinal microbiota induced by HFD and consequently improved the survival rate of zebrafish.


Asunto(s)
Microbioma Gastrointestinal , Hippophae , Animales , Pez Cebra , Dieta Alta en Grasa , Inflamación/genética , Hígado/metabolismo , Estrés Oxidativo , Metabolismo de los Lípidos , Polisacáridos/farmacología , Lípidos/farmacología
20.
Fish Physiol Biochem ; 48(6): 1701-1716, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36348187

RESUMEN

This study aims to explore the effects of dietary selenium on hepatic mitochondrial quality and energy supply of grass carp (Ctenopharyngodon idella) fed with high-fat diet (HFD) after heat stress (HS). Grass carp were fed with HFD, and HFD contained 0.3 mg/kg nano-selenium for 10 weeks, thereafter exposed to HS from 26 to 34 °C, and named the HFD + HS (control) group and the HFD + Se + HS group, respectively. The results show that selenium significantly prompted the growth, increased glutathione peroxidase (GPX) activity, but reduced malondialdehyde (MDA) content in the liver and the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the serum of grass carp fed with HFD after HS. Further, selenium alleviated mitochondrial damage and increased the number of mitochondrial DNA copies in the liver of the grass carp fed with HFD after HS. And selenium also maintained mitochondrial homeostasis by upregulating the expression of mitochondrial quality control-related genes (pgc-1α, nrf1/2, tfam, opa1, mfn1/2, and drp1), mitophagy-related genes (beclin1, atg5, atg12, pink1, and parkin), and the protein expression of parkin and LC3-II/I in the liver of grass carp. Finally, selenium reduced the triglyceride (TG) level and increased the free fatty acid (FFA) level and adenosine triphosphate (ATP) production in the liver of grass carp fed with HFD after HS. In conclusion, dietary selenium alleviated liver damage and improved liver mitochondrial quality and ATP production by increasing liver antioxidant capacity and promoting liver mitochondrial quality in grass carp fed with HFD after HS, which help grass carp to resist these two stressors.


Asunto(s)
Carpas , Selenio , Animales , Suplementos Dietéticos , Dieta , Dieta Alta en Grasa , Carpas/metabolismo , Proteínas de Peces/genética , Antioxidantes/metabolismo , Hígado/metabolismo , Alimentación Animal/análisis
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