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1.
Nature ; 583(7816): 385-390, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32669694

RESUMEN

High-speed actuation of laser frequency1 is critical in applications using lasers and frequency combs2,3, and is a prerequisite for phase locking, frequency stabilization and stability transfer among optical carriers. For example, high-bandwidth feedback control of frequency combs is used in optical-frequency synthesis4, frequency division5 and optical clocks6. Soliton microcombs7,8 have emerged as chip-scale frequency comb sources, and have been used in system-level demonstrations9,10. Yet integrated microcombs using thermal heaters have limited actuation bandwidths11,12 of up to 10 kilohertz. Consequently, megahertz-bandwidth actuation and locking of microcombs have only been achieved with off-chip bulk component modulators. Here we demonstrate high-speed soliton microcomb actuation using integrated piezoelectric components13. By monolithically integrating AlN actuators14 on ultralow-loss Si3N4 photonic circuits15, we demonstrate voltage-controlled soliton initiation, tuning and stabilization with megahertz bandwidth. The AlN actuators use 300 nanowatts of power and feature bidirectional tuning, high linearity and low hysteresis. They exhibit a flat actuation response up to 1 megahertz-substantially exceeding bulk piezo tuning bandwidth-that is extendable to higher frequencies by overcoming coupling to acoustic contour modes of the chip. Via synchronous tuning of the laser and the microresonator, we exploit this ability to frequency-shift the optical comb spectrum (that is, to change the comb's carrier-envelope offset frequency) and make excursions beyond the soliton existence range. This enables a massively parallel frequency-modulated engine16,17 for lidar (light detection and ranging), with increased frequency excursion, lower power and elimination of channel distortions resulting from the soliton Raman self-frequency shift. Moreover, by modulating at a rate matching the frequency of high-overtone bulk acoustic resonances18, resonant build-up of bulk acoustic energy allows a 14-fold reduction of the required driving voltage, making it compatible with CMOS (complementary metal-oxide-semiconductor) electronics. Our approach endows soliton microcombs with integrated, ultralow-power and fast actuation, expanding the repertoire of technological applications of microcombs.

2.
Nature ; 582(7812): 365-369, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32555486

RESUMEN

Optical frequency combs have a wide range of applications in science and technology1. An important development for miniature and integrated comb systems is the formation of dissipative Kerr solitons in coherently pumped high-quality-factor optical microresonators2-9. Such soliton microcombs10 have been applied to spectroscopy11-13, the search for exoplanets14,15, optical frequency synthesis16, time keeping17 and other areas10. In addition, the recent integration of microresonators with lasers has revealed the viability of fully chip-based soliton microcombs18,19. However, the operation of microcombs requires complex startup and feedback protocols that necessitate difficult-to-integrate optical and electrical components, and microcombs operating at rates that are compatible with electronic circuits-as is required in nearly all comb systems-have not yet been integrated with pump lasers because of their high power requirements. Here we experimentally demonstrate and theoretically describe a turnkey operation regime for soliton microcombs co-integrated with a pump laser. We show the appearance of an operating point at which solitons are immediately generated by turning the pump laser on, thereby eliminating the need for photonic and electronic control circuitry. These features are combined with high-quality-factor Si3N4 resonators to provide microcombs with repetition frequencies as low as 15 gigahertz that are fully integrated into an industry standard (butterfly) package, thereby offering compelling advantages for high-volume production.

3.
Nature ; 578(7796): 577-581, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32076270

RESUMEN

Hydrogen peroxide (H2O2) is a major reactive oxygen species in unicellular and multicellular organisms, and is produced extracellularly in response to external stresses and internal cues1-4. H2O2 enters cells through aquaporin membrane proteins and covalently modifies cytoplasmic proteins to regulate signalling and cellular processes. However, whether sensors for H2O2 also exist on the cell surface remains unknown. In plant cells, H2O2 triggers an influx of Ca2+ ions, which is thought to be involved in H2O2 sensing and signalling. Here, by using forward genetic screens based on Ca2+ imaging, we isolated hydrogen-peroxide-induced Ca2+ increases (hpca) mutants in Arabidopsis, and identified HPCA1 as a leucine-rich-repeat receptor kinase belonging to a previously uncharacterized subfamily that features two extra pairs of cysteine residues in the extracellular domain. HPCA1 is localized to the plasma membrane and is activated by H2O2 via covalent modification of extracellular cysteine residues, which leads to autophosphorylation of HPCA1. HPCA1 mediates H2O2-induced activation of Ca2+ channels in guard cells and is required for stomatal closure. Our findings help to identify how the perception of extracellular H2O2 is integrated with responses to various external stresses and internal cues in plants, and have implications for the design of crops with enhanced fitness.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Peróxido de Hidrógeno/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Calcio/metabolismo , Canales de Calcio/metabolismo , Señalización del Calcio , Cisteína/química , Cisteína/metabolismo , Activación Enzimática , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Mutación , Oxidación-Reducción , Células Vegetales/metabolismo , Dominios Proteicos , Proteínas Serina-Treonina Quinasas/química , Proteínas Serina-Treonina Quinasas/genética
4.
J Virol ; 98(3): e0191523, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38334327

RESUMEN

As an intrinsic cellular mechanism responsible for the internalization of extracellular ligands and membrane components, caveolae-mediated endocytosis (CavME) is also exploited by certain pathogens for endocytic entry [e.g., Newcastle disease virus (NDV) of paramyxovirus]. However, the molecular mechanisms of NDV-induced CavME remain poorly understood. Herein, we demonstrate that sialic acid-containing gangliosides, rather than glycoproteins, were utilized by NDV as receptors to initiate the endocytic entry of NDV into HD11 cells. The binding of NDV to gangliosides induced the activation of a non-receptor tyrosine kinase, Src, leading to the phosphorylation of caveolin-1 (Cav1) and dynamin-2 (Dyn2), which contributed to the endocytic entry of NDV. Moreover, an inoculation of cells with NDV-induced actin cytoskeletal rearrangement through Src to facilitate NDV entry via endocytosis and direct fusion with the plasma membrane. Subsequently, unique members of the Rho GTPases family, RhoA and Cdc42, were activated by NDV in a Src-dependent manner. Further analyses revealed that RhoA and Cdc42 regulated the activities of specific effectors, cofilin and myosin regulatory light chain 2, responsible for actin cytoskeleton rearrangement, through diverse intracellular signaling cascades. Taken together, our results suggest that an inoculation of NDV-induced Src-mediated cellular activation by binding to ganglioside receptors. This process orchestrated NDV endocytic entry by modulating the activities of caveolae-associated Cav1 and Dyn2, as well as specific Rho GTPases and downstream effectors. IMPORTANCE: In general, it is known that the paramyxovirus gains access to host cells through direct penetration at the plasma membrane; however, emerging evidence suggests more complex entry mechanisms for paramyxoviruses. The endocytic entry of Newcastle disease virus (NDV), a representative member of the paramyxovirus family, into multiple types of cells has been recently reported. Herein, we demonstrate the binding of NDV to induce ganglioside-activated Src signaling, which is responsible for the endocytic entry of NDV through caveolae-mediated endocytosis. This process involved Src-dependent activation of the caveolae-associated Cav1 and Dyn2, as well as specific Rho GTPase and downstream effectors, thereby orchestrating the endocytic entry process of NDV. Our findings uncover a novel molecular mechanism of endocytic entry of NDV into host cells and provide novel insight into paramyxovirus mechanisms of entry.


Asunto(s)
Macrófagos , Enfermedad de Newcastle , Virus de la Enfermedad de Newcastle , Transducción de Señal , Internalización del Virus , Animales , Endocitosis , Gangliósidos/metabolismo , Macrófagos/metabolismo , Macrófagos/virología , Enfermedad de Newcastle/virología , Virus de la Enfermedad de Newcastle/fisiología , Proteínas de Unión al GTP rho/metabolismo
5.
BMC Biotechnol ; 24(1): 12, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38454400

RESUMEN

OBJECTIVE: The objective of this study was to establish a methodology for determining carboxymethyl lysine (CML) and carboxyethyl lysine (CEL) concentrations in human plasma using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The test results were also used for clinical aging research. METHODS: Human plasma samples were incubated with aqueous perfluorovaleric acid (NFPA), succeeded by precipitation utilizing trichloroacetic acid, hydrolysis facilitated by hydrochloric acid, nitrogen drying, and ultimate re-dissolution utilizing NFPA, followed by filtration. Cotinine-D3 was added as an internal standard. The separation was performed on an Agela Venusil ASB C18 column (50 mm × 4.6 mm, 5 µm) with a 5 mmol/L NFPA and acetonitrile/water of 60:40 (v/v) containing 0.15% formic acid. The multiple reaction monitoring mode was used for detecting CML, CEL, and cotinine-D3, with ion pairs m/z 205.2 > 84.1 (for quantitative) and m/z 205.2 > m/z 130.0 for CML, m/z 219.1 > 84.1 (for quantitative) and m/z 219.1 > m/z 130.1 for CEL, and m/z 180.1 > 80.1 for cotinine-D3, respectively. RESULTS: The separation of CML and CEL was accomplished within a total analysis time of 6 minutes. The retention times of CML, CEL, and cotinine-D3 were 3.43 minutes, 3.46 minutes, and 4.50 minutes, respectively. The assay exhibited linearity in the concentration range of 0.025-1.500 µmol/L, with a lower limit of quantification of 0.025 µmol/L for both compounds. The relative standard deviations of intra-day and inter-day were both below 9%, and the relative errors were both within the range of ±4%. The average recoveries were 94.24% for CML and 97.89% for CEL. CONCLUSION: The results indicate that the developed methodology is fast, highly sensitive, highly specific, reproducible, and suitable for the rapid detection of CML and CEL in clinical human plasma samples. The outcomes of the clinical research project on aging underscored the important indicative significance of these two indicators for research on human aging.


Asunto(s)
Lisina , Espectrometría de Masas en Tándem , Humanos , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Lisina/análisis , Lisina/química , Cotinina , Gerociencia , Productos Finales de Glicación Avanzada/análisis , Productos Finales de Glicación Avanzada/química , Cromatografía Líquida de Alta Presión
6.
FASEB J ; 37(12): e23285, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37933950

RESUMEN

Although certain progress has been made in treating canine inflammatory bowel disease (IBD), a large proportion of dogs have a poor prognosis and may develop resistance and side effects. Therefore, it is of great significance to prevent or alleviate canine IBD through nutritional intervention. Plant polyphenol can interact with intestinal bacteria and has important prospects in the intestinal health improvement. This study evaluated the effect of grape seed proanthocyanidin (GSP), a plant-derived natural polyphenol, on Labrador Retrievers with mild IBD. In Experiment 1 of this study, GSP alleviated persistent intestinal inflammation in canines by improving inflammatory indexes and reducing intestinal permeability. Moreover, GSP treatment increased the abundance of bacteria with potential anti-inflammatory properties and engaging bile acid metabolism, including Ruminococcaceae, Faecalibacterium, Ruminococcus_torques_group, and Lachnospiraceae_NK4A136_group. Notably, targeted metabolomic analysis identified elevated productions of fecal chenodeoxycholic acid and its microbial transformation product lithocholic acid, which might contribute to relieving canine intestinal inflammation. Further, in Experiment 2, fecal microbiota transplantation was used to determine whether gut microbiota is a potential mechanism for GSP efficacy. Dogs with mild IBD received the fecal microbiota from the group administered GSP and mirrored the improvement effects of GSP, which results verified that gut microbial alteration could be an underlying mechanism for GSP efficiency on canine IBD. Our findings highlight that the mechanism of the GSP function on canine IBD is mediated by altering gut microbial composition and improving bile acid metabolism. This study proposes a natural polyphenol-based dietary strategy for improving canine intestinal health.


Asunto(s)
Microbioma Gastrointestinal , Enfermedades Inflamatorias del Intestino , Perros , Animales , Ácidos y Sales Biliares , Enfermedades Inflamatorias del Intestino/microbiología , Inflamación , Polifenoles/farmacología
7.
J Craniofac Surg ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856234

RESUMEN

BACKGROUND: The posterior auricular flap has long been favored for repairing skin defects on the ear's surface. However, achieving optimal esthetic outcomes in ear reconstruction requires a flexible approach to flap transfer methods. While bipedicle advancement flaps are commonly used for body wound coverage, they are rarely used in auricular defect repair. OBJECTIVE: To propose a modified flap transfer approach based on the orientation of the auricular defect's long axis and assess the postoperative esthetic outcomes. METHODS: The authors reported 12 patients treated using 2 distinct flap transfer techniques. Mild to moderate helix soft tissue defects remained after excision of the masses. A direct island flap was created for patients with longitudinal defects to cover the defect. For patients with transverse defects, a combination of bipedicle and island flaps was used for repair. Scar quality and esthetic outcomes were assessed at least 6 months postsurgery using the Scar Cosmesis Assessment and Rating scale. RESULTS: All patients experienced no serious complications and achieved excellent cosmetic results. Patients undergoing combined flap transfer exhibited relatively more favorable esthetic outcomes. CONCLUSION: The authors propose a novel concept for repairing helix soft tissue defects by designing local flaps based on the direction of the defect's long axis. For repairing helix soft tissue defects with a long axis parallel to the auricular edge, the combined utilization of bipedicle advancement flap and island rotation flap transfer should be consideration more.

8.
J Craniofac Surg ; 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38385675

RESUMEN

BACKGROUND: Based on the knowledge of facial vascularity, facial artery perforator flaps could be used as potent tools for facial defect reconstruction. However, lack of experience and misconception of this technique limits the broad application in the clinical background. Here, we discussed surgical techniques based on our previous experience with facial artery perforator (FAP)-based facial defect reconstruction. METHODS: A retrospective review of 12 patients undergoing facial defect reconstruction using an FAP flap was performed, including 8 defects in the mid-facial part and 4 defects in the nasal area generally resulted from basal cell carcinoma (8 patients), squamous cell carcinoma (3 patients), and actinic keratosis (one patient). RESULTS: All patients received one-stage FAP flap reconstruction. The overall follow-up period was 6 to 12 months. All reconstructions were successful with satisfactory patient-reported outcome and no local recurrence. No significant complications were observed in most cases, except for one instance of partial flap loss. CONCLUSIONS: Overall, taking advantage of FAP flaps will contribute to a good functional and esthetic outcome of facial defect reconstructions.

9.
Nano Lett ; 23(11): 4699-4707, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-36951377

RESUMEN

Mass transfer is critical in catalytic processes, especially when the reactions are facilitated by nanostructured catalysts. Strong efforts have been devoted to improving the efficacy and quantity of active sites, but often, mass transfer has not been well studied. Herein, we demonstrate the importance of mass transfer in the electrocatalytic oxygen reduction reaction (ORR) by tailoring the pore sizes. Using a confined-etching strategy, we fabricate boron- and nitrogen-doped carbon (B,N@C) electrocatalysts featuring abundant active sites but different porous structures. The ORR performance of these catalysts is found to correlate with diffusion of the reactant. The optimized B,N@C with trimodal-porous structures feature enhanced O2 diffusion and better activity per heteroatomic site toward the ORR process. This work demonstrates the significance of the nanoarchitecture engineering of catalysts and sheds light on how to optimize structures featuring abundant active sites and enhanced mass transfer.

10.
J Environ Manage ; 358: 120924, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38636416

RESUMEN

Solid waste is increasing rapidly worldwide. In this study, the solid waste (household waste, construction and demolition waste and industrial waste) management systems are treated as reverse supply chain to analyze the critical operational issues based on complex adaptive system theory. At the single-layer, the complexity of the various nodes at a layer arises from rational decision-making and behavioral heterogeneity. The solid waste generation layer is employed as an example to investigate the complexity of node behavioral decisions. Regression analysis results reveal that both endogenous (Attitude, Subjective norm, and Perceived behavioral control) and exogenous factors (Economic incentive, Government supervision, Technical support) positively influence sorting behavior. The effect of Economic incentive (ß=0.327P<0.001) and Attitude (ß=0.249P<0.001) on sorting behavior are the largest. In the multi-layer system, different layers communicate with each other through the material and financial flows and have cross-layer impacts. An agent-based model is developed to investigate the multi-layer feedforward influence mechanism of changes in key layers (e.g., sorting rate, disposal rate) and the material and financial flows adaptive adjustment direction of the solid waste reverse supply chain. High rate of participation and accuracy of source sorting can shorten material flow paths and reduce storage and transportation costs. The increase in disposal rate encourages the transition of solid waste from backfill to resource utilization. This study provides a practice reference for solid waste reverse supply chain and related enterprises managers.


Asunto(s)
Residuos Sólidos , Administración de Residuos , Administración de Residuos/métodos , Eliminación de Residuos/métodos
11.
Phys Occup Ther Pediatr ; 44(3): 316-335, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37867378

RESUMEN

AIMS: Extremely premature birth puts infants at high risk for developmental delay and results in parent anxiety and depression. The primary objective of this study was to characterize feasibility and acceptability of a therapist-led, parent-administered therapy and massage program designed to support parent mental health and infant development. METHODS: A single cohort of 25 dyads - parents (24 mothers, 1 father) and extremely preterm (<28 wk gestation) infants - participated in the intervention. During hospitalization, parents attended weekly hands-on education sessions with a primary therapist. Parents received bi-weekly developmental support emails for 12 months post-discharge and were scheduled for 2 outpatient follow up visits. We collected measures of parent anxiety, depression, and competence at baseline, hospital discharge, and <4 and 12 months post-discharge. RESULTS: All feasibility targets were met or exceeded at baseline and discharge (≥70%). Dyads participated in an average of 11 therapy sessions (range, 5-20) during hospitalization. Lower rates of data collection adherence were observed over successive follow ups (range, 40-76%). Parent-rated feasibility and acceptability scores were high at all time points. CONCLUSIONS: Results support parent-rated feasibility and acceptability of the TEMPO intervention for extremely preterm infants and their parents in the Neonatal Intensive Care Unit.


Asunto(s)
Recien Nacido Prematuro , Terapia Ocupacional , Lactante , Femenino , Niño , Recién Nacido , Humanos , Estudios de Factibilidad , Salud Mental , Desarrollo Infantil , Cuidados Posteriores , Alta del Paciente , Padres/psicología , Unidades de Cuidado Intensivo Neonatal
12.
BMC Genomics ; 24(1): 591, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37798722

RESUMEN

BACKGROUND: Circular RNAs (circRNAs), as important non-coding RNAs (ncRNAs), are involved in many biological activities. However, the exact chemical mechanism behind fat accumulation is unknown. In this paper, we obtained the expression profiles of circRNAs using high-throughput sequencing and investigated their differential expression in subcutaneous fat tissue of Duolang and Small Tail Han sheep. RESULTS: From the transcriptomic analysis, 141 differentially expressed circRNAs were identified, comprising 61 up-regulated circRNAs and 80 down-regulated circRNAs. These host genes were primarily enriched in the MAPK and AMPK signaling pathways which is closely associated with fat deposition regulation. We identified circRNA812, circRNA91, and circRNA388 as vital genes in fat deposition by miRNA-circRNA target gene prediction. The functional annotation results of target genes of key circRNAs showed that the signaling pathways mainly included PI3K-Akt and AMPK. We constructed the competing endogenous RNA (ceRNA) regulatory network to study the role of circRNAs in sheep lipid deposition, and circRNA812, circRNA91, and circRNA388 can adsorb more miRNAs. NC_040253.1_5757, as the source of miRNA response element (MRE) among the three, may play an important role during the process of sheep fat deposition. CONCLUSIONS: Our study gives a systematic examination of the circRNA profiles expressed in sheep subcutaneous fat. These results from this study provide some new basis for understanding circRNA function and sheep fat metabolism.


Asunto(s)
MicroARNs , ARN Circular , Animales , Ovinos/genética , Fosfatidilinositol 3-Quinasas/genética , Proteínas Quinasas Activadas por AMP/genética , MicroARNs/genética , MicroARNs/metabolismo , Grasa Subcutánea/metabolismo , Redes Reguladoras de Genes
13.
Biochem Biophys Res Commun ; 677: 20-25, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37542771

RESUMEN

BACKGROUND: Osteoarthritis is one of the most common degenerative joint disorders, characterized by articular cartilage breakdown, synovitis, osteophytes generation and subchondral bone sclerosis. Pentraxin 3 (PTX3) is a long pentraxin protein, secreted by immune cells, and PTX3 is identified to play a critical role in inflammation and macrophage polarization. However, the underlying mechanism of PTX3 in osteoarthritis under the circumstance of Ptx3-knockout (KO) mice model is still unknown. METHODS: Murine destabilization of the medial meniscus (DMM) OA model was created in Ptx3-knockout (KO) and wildtype mice, respectively. The degenerative status of cartilage was detected by Safranin O, H&E staining, immunohistochemistry (IHC) and micro-CT. OARSI scoring was employed to assess the proteoglycan of cartilage. Serum inflammatory cytokines were examined by ELISA and systematic macrophage polarization in spleen was analyzed by flow cytometry. RESULTS: Safranin O and H&E staining confirmed that the joint cartilage was mostly with reduced degeneration in both the senior KO mice and the DMM model generated from the KO mice, compared to the WT group. This is also supported by micro-CT examination and OARSI scoring. Immunohistochemistry illustrated an up-regulation of Aggrecan and Collagen 2 and down-regulation of ADAMTS-5 and MMP13 in KO mice in comparison with the WT mice. ELISA indicated a dramatical decrease in the serum levels of TNF-α and IL-6 in KO mice. Polarization of M2-like macrophages was observed in the KO group. CONCLUSION: Pentraxin 3 deficiency significantly ameliorated the severity of osteoarthritis by preventing cartilage degeneration and alleviated systematic inflammation by inducing M2 polarization.

14.
Small ; 19(32): e2301038, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37069771

RESUMEN

Photo-regulated nanofluidic devices have attracted great attention in recent years due to their adjustable ion transport in real time. However, most of the photo-responsive nanofluidic devices can only adjust the ionic current unidirectionally, and cannot simultaneously increase or decrease the current signal intelligently by one device. Herein, a mesoporous carbon-titania/ anodized aluminum hetero-channels (MCT/AAO) is constructed by super-assembly strategy, which exhibits dual-function of cation selectivity and photo response. The polymer and TiO2 nanocrystals jointly build the MCT framework. Polymer framework with abundant negatively charged sites endows MCT/AAO with excellent cation selectivity, and TiO2 nanocrystals are responsible for the photo-regulated ion transport. High photo current densities of 1.8 mA m-2 (increase) and 1.2 mA m-2 (decrease) are realized by MCT/AAO benefiting from the ordered hetero-channels. Significantly, MCT/AAO can also achieve the bidirectionally adjustable osmotic energy by alternating the configurations of concentration gradient. Theoretical and experimental results reveal that the superior photo-generated potential is responsible for the bidirectionally adjustable ion transport. Consequently, MCT/AAO performs the function of harvesting ionic energy from the equilibrium electrolyte solution, which greatly expands its practical application field. This work provides a new strategy in constructing dual-functional hetero-channels toward bidirectionally photo-regulated ionic transport and energy harvesting.

15.
J Virol ; 96(10): e0024122, 2022 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-35510864

RESUMEN

In this study, 232 class I Newcastle disease viruses (NDVs) were identified from multiple bird species at nationwide live bird markets (LBMs) from 2017 to 2019 in China. Phylogenetic analysis indicated that all 232 isolates were clustered into genotype 1.1.2 of class I on the basis of the fusion (F) gene sequences, which were distinct from the genotypes identified in other countries. Most of the isolates (212/232) were shown to have the typical F gene molecular characteristics of class I NDVs, while a few (20/232) contained mutations at the site of the conventional start codon of the F gene, which resulted in open reading frames (ORFs) altered in length. The isolates with ACG, CTA, and ATA mutations showed different levels of increased virulence and replication capacity, suggesting that these viruses may be transitional types during the evolution of class I NDVs from avirulent to virulent. Further evaluation of biological characteristics with recombinant viruses obtained by reverse genetics demonstrated that the ATG located at genomic positions 4523 to 4525 was the authentic start codon in the F gene of class I NDV, and the specific ATA mutations which contributed to the expression of F protein on the surface of infected cells were the key determinants of increased replication capacity and virulence. Interestingly, the mutation at the corresponding site of genotype II LaSota of class II had no effects on the virulence and replication capacity in chickens. Our results suggest that the alteration of virulence and replication capacity caused by specific mutations in the F gene could be a specific characteristic of class I NDVs and indicate the possibility of the emergence of virulent NDVs due to the persistent circulation of class I NDVs. IMPORTANCE The available information on the distribution, genetic diversity, evolution, and biological characteristics of class I Newcastle disease viruses (NDVs) in domestic poultry is currently very limited. Here, identification of class I NDVs at nationwide live bird markets (LBMs) in China was performed and representative isolates were characterized. A widespread distribution of genotype 1.1.2 of class I NDVs was found in multiple bird species at LBMs in China. Though most isolates demonstrated typical molecular characteristics of class I NDVs, a few that contained specific mutations at the site of the conventional start codon of the fusion gene with increased virulence and replication capacity were identified for the first time. Our findings indicate that the virulence of class I NDVs could have evolved, and the widespread transmission and circulation of class I NDVs may represent a potential threat for disease outbreaks in poultry.


Asunto(s)
Enfermedad de Newcastle , Enfermedades de las Aves de Corral , Animales , Pollos/virología , China/epidemiología , Codón Iniciador , Comercio , Monitoreo Epidemiológico/veterinaria , Genotipo , Enfermedad de Newcastle/epidemiología , Virus de la Enfermedad de Newcastle/genética , Filogenia , Aves de Corral/virología , Enfermedades de las Aves de Corral/epidemiología , Virulencia/genética
16.
BMC Cancer ; 23(1): 596, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37380984

RESUMEN

BACKGROUND: Glioma is the most common malignant primary brain tumor and is characterized by a poor prognosis and limited therapeutic options. ISG20 expression is induced by interferons or double-stranded RNA and is associated with poor prognosis in several malignant tumors. Nevertheless, the expression of ISG20 in gliomas, its impact on patient prognosis, and its role in the tumor immune microenvironment have not been fully elucidated. METHODS: Using bioinformatics, we comprehensively illustrated the potential function of ISG20, its predictive value in stratifying clinical prognosis, and its association with immunological characteristics in gliomas. We also confirmed the expression pattern of ISG20 in glioma patient samples by immunohistochemistry and immunofluorescence staining. RESULTS: ISG20 mRNA expression was higher in glioma tissues than in normal tissues. Data-driven results showed that a high level of ISG20 expression predicted an unfavorable clinical outcome in glioma patients, and revealed that ISG20 was possibly expressed on tumor-associated macrophages and was significantly associated with immune regulatory processes, as evidenced by its positive correlation with the infiltration of regulatory immune cells (e.g., M2 macrophages and regulatory T cells), expression of immune checkpoint molecules, and effectiveness of immune checkpoint blockade therapy. Furthermore, immunohistochemistry staining confirmed the enhanced expression of ISG20 in glioma tissues with a higher WHO grade, and immunofluorescence assay verified its cellular localization on M2 macrophages. CONCLUSIONS: ISG20 is expressed on M2 macrophages, and can serve as a novel indicator for predicting the malignant phenotype and clinical prognosis in glioma patients.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Pronóstico , Glioma/genética , Macrófagos , Neoplasias Encefálicas/genética , Biología Computacional , Microambiente Tumoral , Exorribonucleasas
17.
Biomacromolecules ; 24(2): 566-575, 2023 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-36715568

RESUMEN

Changes in mass and viscoelasticity of chitin layers in fungal cell walls during chitinase attack are vital for understanding bacterial invasion of and human defense against fungi. In this work, regenerated chitin (RChitin) thin films mimicked the fungal chitin layers and facilitated studies of degradation by family 18 chitinases from Trichoderma viride (T. viride) and family 19 chitinases from Streptomyces griseus (S. griseus) that possessed chitin-binding domains (CBDs) that were absent in the family 18 chitinases. Degradation was monitored via a quartz crystal microbalance with dissipation monitoring (QCM-D) in real time at various pH and temperatures. Compared to substrates of colloidal chitin or dissolved chitin derivatives and analogues, the degradation of RChitin films was deeply affected by chitinase adsorption. While the family 18 chitinases had greater solution activity on chitin oligosaccharides, the family 19 chitinases exhibited greater surface activity on RChitin films, illustrating the importance of CBDs for insoluble substrates.


Asunto(s)
Quitina , Quitinasas , Streptomyces griseus , Humanos , Quitina/química , Quitina/metabolismo , Quitinasas/química , Quitinasas/metabolismo , Oligosacáridos/química , Oligosacáridos/metabolismo , Streptomyces griseus/metabolismo
18.
Crit Rev Food Sci Nutr ; 63(22): 5594-5607, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34978220

RESUMEN

Nutrients sensing is crucial for fundamental metabolism and physiological functions, and it is also an essential component for maintaining body homeostasis. Traditionally, basic taste receptors exist in oral cavity to sense sour, sweet, bitter, umami, salty and et al. Recent studies indicate that gut can sense the composition of nutrients by activating relevant taste receptors, thereby exerting specific direct or indirect effects. Gut taste receptors, also named as intestinal nutrition receptors, including at least bitter, sweet and umami receptors, have been considered to be activated by certain nutrients and participate in important intestinal physiological activities such as eating behavior, intestinal motility, nutrient absorption and metabolism. Additionally, gut taste receptors can regulate appetite and body weight, as well as maintain homeostasis via targeting hormone secretion or regulating the gut microbiota. On the other hand, malfunction of gut taste receptors may lead to digestive disorders, and then result in obesity, type 2 diabetes and gastrointestinal diseases. At present, researchers have confirmed that the brain-gut axis may play indispensable roles in these diseases via the secretion of brain-gut peptides, but the mechanism is still not clear. In this review, we summarize the current observation of knowledge in gut taste systems in order to shed light on revealing their important nutritional functions and promoting clinical implications.


Asunto(s)
Diabetes Mellitus Tipo 2 , Papilas Gustativas , Humanos , Gusto/fisiología , Diabetes Mellitus Tipo 2/metabolismo , Nutrientes , Dieta , Receptores Acoplados a Proteínas G/fisiología , Percepción del Gusto/fisiología
19.
Cost Eff Resour Alloc ; 21(1): 82, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37932748

RESUMEN

BACKGROUND: In recent years, numerous guidelines and expert consensus have recommended the inclusion of digital technologies and products in cardiac rehabilitation. Digital therapeutics (DTx) is an evidence-based medicine that uses digital means for data collection and monitoring of indicators to control and optimize the treatment, management, and prevention of disease. OBJECTIVE: This study collected and reviewed real-world data and built a model using health economics assessment methods to analyze the potential cost-effectiveness of DTx applied to home-based cardiac rehabilitation for patients with chronic heart failure. From the perspective of medical and health decision-makers, the economic value of DTx is evaluated prospectively to provide the basis and reference for the application decision and promotion of DTx. METHODS: Markov models were constructed to simulate the outcomes of DTx for home-based cardiac rehabilitation (DT group) compared to conventional home-based cardiac rehabilitation (CH group) in patients with chronic heart failure. The model input parameters were clinical indicators and cost data. Outcome indicators were quality-adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs). The robustness of the evaluation methods and results was tested using sensitivity analyses. Clinical indicators, cost data, and health utility values were obtained from real-world data, including clinical study data, published literature, and public website information. RESULTS: The Markov model simulated a time span of 10 years, with a cycle set at one month, for 120 cycles. The results showed that the per capita cost of the CH group was 38,442.11 CNY/year, with a QALY of 0.7196 per person per year. The per capita cost of the DT group was 42,300.26 CNY/year, with a QALY of 0.81687 per person per year. The ICER per person was 39,663.5 CNY/QALY each year, which was below the willingness-to-pay threshold of 85,698 CNY (China's GDP per capita in 2022). CONCLUSIONS: DTx for home-based cardiac rehabilitation is an extremely cost-effective rehabilitation option compared with conventional home-based cardiac rehabilitation. DTx for home-based cardiac rehabilitation is potentially valuable from the perspective of healthcare decision-makers.

20.
Arch Toxicol ; 97(4): 1147-1162, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36800006

RESUMEN

Cisplatin is highly effective for killing tumor cells. However, as one of its side effects, ototoxicity limits the clinical application of cisplatin. The mechanisms of cisplatin-induced ototoxicity have not been fully clarified yet. SIRT3 is a deacetylated protein mainly located in mitochondria, which regulates a variety of physiological processes in cells. The role of SIRT3 in cisplatin-induced hair cell injury has not been founded. In this study, primary cultured cochlear explants exposed to 5 µM cisplatin, as well as OC-1 cells exposed to 10 µM cisplatin, were used to establish models of cisplatin-induced ototoxicity in vitro. We found that when combined with cisplatin, metformin (75 µM) significantly up-regulated the expression of SIRT3 and alleviated cisplatin-induced apoptosis of hair cells. We regulated the expression of SIRT3 to explore the role of SIRT3 in cisplatin-induced auditory hair cell injury. Overexpression of SIRT3 promoted the survival of auditory hair cells and alleviated the apoptosis of auditory hair cells. In contrast, knockdown of SIRT3 impaired the protective effect of metformin and exacerbated cisplatin injury. In addition, we found that the protective effect of SIRT3 may be achieved by regulating GLUT4 translocation and rescuing impaired glucose uptake caused by cisplatin. Our study confirmed that upregulation of SIRT3 may antagonize cisplatin-induced ototoxicity, and provided a new perspective for the study of cisplatin-induced ototoxicity.


Asunto(s)
Antineoplásicos , Metformina , Ototoxicidad , Sirtuina 3 , Humanos , Cisplatino/toxicidad , Antineoplásicos/toxicidad , Sirtuina 3/genética , Ototoxicidad/etiología , Ototoxicidad/prevención & control , Metformina/farmacología , Apoptosis
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