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1.
J Virol ; 97(10): e0076023, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37754759

RESUMEN

IMPORTANCE: The biogenesis and clinical application of serum HBV pgRNA have been a research hotspot in recent years. This study further characterized the heterogeneity of the 3' terminus of capsid RNA by utilizing a variety of experimental systems conditionally supporting HBV genome replication and secretion, and reveal that the 3' truncation of capsid pgRNA is catalyzed by cellular ribonuclease(s) and viral RNaseH at positions after and before 3' DR1, respectively, indicating the 3' DR1 as a boundary between the encapsidated portion of pgRNA for reverse transcription and the 3' unprotected terminus, which is independent of pgRNA length and the 3' terminal sequence. Thus, our study provides new insights into the mechanism of pgRNA encapsidation and reverse transcription, as well as the optimization of serum HBV RNA diagnostics.


Asunto(s)
Cápside , Genoma Viral , Virus de la Hepatitis B , ARN Viral , Replicación Viral , Cápside/metabolismo , Genoma Viral/genética , Hepatitis B/diagnóstico , Hepatitis B/virología , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/crecimiento & desarrollo , Virus de la Hepatitis B/metabolismo , Transcripción Reversa , Ribonucleasa H/metabolismo , ARN Viral/genética , ARN Viral/metabolismo , Replicación Viral/genética
2.
PLoS Pathog ; 18(6): e1010576, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35679251

RESUMEN

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA), serving as the viral persistence form and transcription template of HBV infection, hijacks host histone and non-histone proteins to form a minichromosome and utilizes posttranslational modifications (PTMs) "histone code" for its transcriptional regulation. HBV X protein (HBx) is known as a cccDNA transcription activator. In this study we established a dual system of the inducible reporter cell lines modelling infection with wildtype (wt) and HBx-null HBV, both secreting HA-tagged HBeAg as a semi-quantitative marker for cccDNA transcription. The cccDNA-bound histone PTM profiling of wt and HBx-null systems, using chromatin immunoprecipitation coupled with quantitative PCR (ChIP-qPCR), confirmed that HBx is essential for maintenance of cccDNA at transcriptionally active state, characterized by active histone PTM markers. Differential proteomics analysis of cccDNA minichromosome established in wt and HBx-null HBV cell lines revealed group-specific hits. One of the hits in HBx-deficient condition was a non-histone host DNA-binding protein high mobility group box 1 (HMGB1). Its elevated association to HBx-null cccDNA was validated by ChIP-qPCR assay in both the HBV stable cell lines and infection systems in vitro. Furthermore, experimental downregulation of HMGB1 in HBx-null HBV inducible and infection models resulted in transcriptional re-activation of the cccDNA minichromosome, accompanied by a switch of the cccDNA-associated histones to euchromatic state with activating histone PTMs landscape and subsequent upregulation of cccDNA transcription. Mechanistically, HBx interacts with HMGB1 and prevents its binding to cccDNA without affecting the steady state level of HMGB1. Taken together, our results suggest that HMGB1 is a novel host restriction factor of HBV cccDNA with epigenetic silencing mechanism, which can be counteracted by viral transcription activator HBx.


Asunto(s)
Proteína HMGB1 , Hepatitis B , ADN Circular/genética , ADN Circular/metabolismo , ADN Viral/genética , ADN Viral/metabolismo , Epigénesis Genética , Proteína HMGB1/genética , Células Hep G2 , Virus de la Hepatitis B/metabolismo , Histonas/metabolismo , Humanos , Transactivadores , Factores de Transcripción/metabolismo , Proteínas Reguladoras y Accesorias Virales , Replicación Viral/genética
3.
Microb Pathog ; 190: 106638, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38574829

RESUMEN

Autophagy plays an important role in the lifecycle of viruses. However, there is currently a lack of systematic research on the relationship between Infectious Bronchitis Virus (IBV) and autophagy. This study aims to investigate the impact of IBV on autophagy and the role of autophagy in viral replication. We observed that IBV infection increased the expression of microtubule-associated protein 1 light chain 3, a marker of autophagy, decreased the expression of sequestosome 1, and led to elevated intracellular LC3 puncta levels. These findings suggest that IBV infection activates the autophagic process in cells. To investigate the impact of autophagy on the replication of IBV, we utilized rapamycin as an autophagy activator and 3-methyladenine as an autophagy inhibitor. Our results indicate that IBV promotes viral replication by inducing autophagy. Further investigation revealed that IBV induces autophagosome formation by inhibiting the mTOR-ULK1 pathway and activating the activity of vacuolar protein sorting 34 (VPS34), autophagy-related gene 14, and the Beclin-1 complex. VPS34 plays a crucial role in this process, as inhibiting VPS34 protein activity enhances cell proliferation after IBV infection. Additionally, inhibiting VPS34 significantly improves the survival rate of IBV-infected chicks, suppresses IBV replication in the kidney, and alleviates tracheal, lung, and kidney damage caused by IBV infection. In summary, IBV infection can induce autophagy by modulating the mTOR/ULK1 signaling pathway and activating the VPS34 complex, while autophagy serves to promote virus replication.


Asunto(s)
Autofagia , Pollos , Fosfatidilinositol 3-Quinasas Clase III , Virus de la Bronquitis Infecciosa , Replicación Viral , Virus de la Bronquitis Infecciosa/fisiología , Animales , Fosfatidilinositol 3-Quinasas Clase III/metabolismo , Pollos/virología , Infecciones por Coronavirus/virología , Infecciones por Coronavirus/metabolismo , Sirolimus/farmacología , Beclina-1/metabolismo , Beclina-1/genética , Serina-Treonina Quinasas TOR/metabolismo , Transducción de Señal , Línea Celular , Enfermedades de las Aves de Corral/virología , Autofagosomas/metabolismo , Autofagosomas/virología , Chlorocebus aethiops , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Asociadas a Microtúbulos/genética
4.
Cell Commun Signal ; 22(1): 300, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38816763

RESUMEN

Optimizing the efficiency of definitive endoderm (DE) differentiation is necessary for the generation of diverse organ-like structures. In this study, we used the small molecule inhibitor saracatinib (SAR) to enhance DE differentiation of human embryonic stem cells and induced pluripotent stem cells. SAR significantly improved DE differentiation efficiency at low concentrations. The interaction between SAR and Focal Adhesion Kinase (FAK) was explored through RNA-seq and molecular docking simulations, which further supported the inhibition of DE differentiation by p-FAK overexpression in SAR-treated cells. In addition, we found that SAR inhibited the nuclear translocation of Yes-associated protein (YAP), a downstream effector of FAK, which promoted DE differentiation. Moreover, the addition of SAR enabled a significant reduction in activin A (AA) from 50 to 10 ng/mL without compromising DE differentiation efficiency. For induction of the pancreatic lineage, 10 ng/ml AA combined with SAR at the DE differentiation stage yielded a comparative number of PDX1+/NKX6.1+ pancreatic progenitor cells to those obtained by 50 ng/ml AA treatment. Our study highlights SAR as a potential modulator that facilitates the cost-effective generation of DE cells and provides insight into the orchestration of cell fate determination.


Asunto(s)
Benzodioxoles , Diferenciación Celular , Endodermo , Quinazolinas , Transducción de Señal , Humanos , Diferenciación Celular/efectos de los fármacos , Endodermo/efectos de los fármacos , Endodermo/citología , Endodermo/metabolismo , Benzodioxoles/farmacología , Transducción de Señal/efectos de los fármacos , Quinazolinas/farmacología , Factores de Transcripción/metabolismo , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/citología , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Señalizadoras YAP/metabolismo , Quinasa 1 de Adhesión Focal/metabolismo , Quinasa 1 de Adhesión Focal/genética , Células Madre Embrionarias Humanas/efectos de los fármacos , Células Madre Embrionarias Humanas/metabolismo , Células Madre Embrionarias Humanas/citología , Activinas/metabolismo , Simulación del Acoplamiento Molecular
5.
Ren Fail ; 46(2): 2365408, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38874119

RESUMEN

Podocyte loss in glomeruli is a fundamental event in the pathogenesis of chronic kidney diseases. Currently, mitotic catastrophe (MC) has emerged as the main cause of podocyte loss. However, the regulation of MC in podocytes has yet to be elucidated. The current work aimed to study the role and mechanism of p53 in regulating the MC of podocytes using adriamycin (ADR)-induced nephropathy. In vitro podocyte stimulation with ADR triggered the occurrence of MC, which was accompanied by hyperactivation of p53 and cyclin-dependent kinase (CDK1)/cyclin B1. The inhibition of p53 reversed ADR-evoked MC in podocytes and protected against podocyte injury and loss. Further investigation showed that p53 mediated the activation of CDK1/cyclin B1 by regulating the expression of Wee1. Restraining Wee1 abolished the regulatory effect of p53 inhibition on CDK1/cyclin B1 and rebooted MC in ADR-stimulated podocytes via p53 inhibition. In a mouse model of ADR nephropathy, the inhibition of p53 ameliorated proteinuria and podocyte injury. Moreover, the inhibition of p53 blocked the progression of MC in podocytes in ADR nephropathy mice through the regulation of the Wee1/CDK1/cyclin B1 axis. Our findings confirm that p53 contributes to MC in podocytes through regulation of the Wee1/CDK1/Cyclin B1 axis, which may represent a novel mechanism underlying podocyte injury and loss during the progression of chronic kidney disorder.


Asunto(s)
Proteína Quinasa CDC2 , Proteínas de Ciclo Celular , Ciclina B1 , Doxorrubicina , Mitosis , Podocitos , Proteínas Tirosina Quinasas , Proteína p53 Supresora de Tumor , Podocitos/metabolismo , Podocitos/patología , Animales , Proteína Quinasa CDC2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Ratones , Proteínas Tirosina Quinasas/metabolismo , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Doxorrubicina/farmacología , Ciclina B1/metabolismo , Proteínas de Ciclo Celular/metabolismo , Modelos Animales de Enfermedad , Humanos , Masculino
6.
Cancer Immunol Immunother ; 72(11): 3453-3460, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37733059

RESUMEN

Tumor-infiltrating T cells are promising drug targets to modulate the tumor microenvironment. However, tumor-infiltrating T lymphocytes, as central targets of cancer immunotherapy, show considerable heterogeneity and dynamics across tumor microenvironments and cancer types that may fundamentally influence cancer growth, metastasis, relapse, and response to clinical drugs. The T cell heterogeneity not only refers to the composition of subpopulations but also divergent metabolic states of T cells. Comparing to the diversity of tumor-infiltrating T cell compositions that have been well recognized, the metabolic diversity of T cells deserves more attention for precision immunotherapy. Single-cell sequencing technology enables panoramic stitching of the tumor bulk, partly by showing the metabolic-related gene expression profiles of tumor-infiltrating T cells at a single-cell resolution. Therefore, we here discuss T cell metabolism reprogramming triggered by tumor microenvironment as well as the potential application of metabolic targeting drugs. The tumor-infiltrating T cells metabolic pathway addictions among different cancer types are also addressed in this brief review.


Asunto(s)
Neoplasias , Linfocitos T , Humanos , Linfocitos T/metabolismo , Recurrencia Local de Neoplasia/metabolismo , Neoplasias/patología , Linfocitos Infiltrantes de Tumor , Inmunoterapia , Microambiente Tumoral
7.
J Virol ; 96(2): e0136021, 2022 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-34705558

RESUMEN

Hepatitis B virus (HBV) utilizes host DNA repair mechanisms to convert viral relaxed circular DNA (rcDNA) into a persistent viral genome, the covalently closed circular DNA (cccDNA). To identify host factors involved in cccDNA formation, we developed an unbiased approach to discover proteins involved in cccDNA formation by precipitating nuclear rcDNA from induced HepAD38 cells and identifying the coprecipitated proteins by mass spectrometry. DNA damage binding protein 1 (DDB1) surfaced as a hit, coinciding with our previously reported short hairpin RNA (shRNA) screen in which shRNA-DDB1 in HepDES19 cells reduced cccDNA production. DDB1 binding to nuclear rcDNA was confirmed in HepAD38 cells via ChIP-qPCR. DDB1 and DNA damage binding protein 2 (DDB2) form the UV-DDB complex, and the latter senses DNA damage to initiate the global genome nucleotide excision repair (GG-NER) pathway. To investigate the role of the DDB complex in cccDNA formation, DDB2 was knocked out in HepAD38 and HepG2-NTCP cells. In both knockout cell lines, cccDNA formation was stunted significantly, and in HepG2-NTCP-DDB2 knockout cells, downstream indicators of cccDNA such as HBV RNA, HBcAg, and HBeAg were similarly reduced. Knockdown of DDB2 in HBV-infected HepG2-NTCP cells and primary human hepatocytes (PHH) also resulted in cccDNA reduction. Transcomplementation of wild-type DDB2 in HepG2-NTCP-DDB2 knockout cells rescued cccDNA formation and its downstream indicators. However, ectopic expression of DDB2 mutants deficient in DNA binding, DDB1 binding, or ubiquitination failed to rescue cccDNA formation. Our study thus suggests an integral role of UV-DDB, specifically DDB2, in the formation of HBV cccDNA. IMPORTANCE Serving as a key viral factor for chronic hepatitis B virus (HBV) infection, HBV covalently closed circular DNA (cccDNA) is formed in the cell nucleus from viral relaxed circular DNA (rcDNA) by hijacking host DNA repair machinery. Previous studies have identified several host DNA repair factors involved in cccDNA formation through hypothesis-driven research with some help from RNA interference (RNAi) screening and/or biochemistry approaches. To enrich the landscape of tools for discovering host factors responsible for rcDNA-to-cccDNA conversion, we developed an rcDNA immunoprecipitation paired mass spectrometry assay, which allowed us to pull down nuclear rcDNA in its transitional state to cccDNA and observe the associated host factors. From this assay, we discovered a novel relationship between the UV-DDB complex and cccDNA formation, providing a proof of concept for a more direct discovery of novel HBV DNA-host interactions that can be exploited to develop new cccDNA-targeting antivirals.


Asunto(s)
ADN Circular/metabolismo , ADN Viral/metabolismo , Proteínas de Unión al ADN/metabolismo , Virus de la Hepatitis B/fisiología , Línea Celular , Núcleo Celular/metabolismo , Núcleo Celular/virología , Replicación del ADN , Proteínas de Unión al ADN/genética , Antígenos de la Hepatitis B/metabolismo , Virus de la Hepatitis B/metabolismo , Humanos , Unión Proteica , Proteómica , ARN Viral/metabolismo , Ubiquitinación , Replicación Viral
8.
Opt Express ; 31(9): 14570-14582, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37157318

RESUMEN

A compact fiber-optic temperature sensor with hybrid interferometers enhanced by the harmonic Vernier effect was proposed, which realized 36.9 times sensitization of the sensing Fabry-Perot interferometer (FPI). The hybrid interferometers configuration of the sensor consists of a FPI and a Michelson interferometer. The proposed sensor is fabricated by splicing the hole-assisted suspended-core fiber (HASCF) to the multi-mode fiber fused with the single-mode fiber, and filling polydimethylsiloxane (PDMS) into the air hole of HASCF. The high thermal expansion coefficient of PDMS improves the temperature sensitivity of the FPI. The harmonic Vernier effect eliminates the limitation of the free spectral range on the magnification factor by detecting the intersection response of internal envelopes, and realizes the secondary sensitization of the traditional Vernier effect. Combing the characteristics of HASCF, PDMS, and first-order harmonic Vernier effect, the sensor exhibits a high detection sensitivity of -19.22 nm/°C. The proposed sensor provides not only a design scheme for compact fiber-optic sensors, but also a new strategy to enhance the optical Vernier effect.

9.
Virol J ; 20(1): 18, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36721152

RESUMEN

Coronavirus disease 2019 is a global pandemic caused by SARS-CoV-2. The emergence of its variant strains has posed a considerable challenge to clinical treatment. Therefore, drugs capable of inhibiting SARS-CoV-2 infection, regardless of virus variations, are in urgently need. Our results showed that the endosomal acidification inhibitor, Bafilomycin A1 (Baf-A1), had an inhibitory effect on the viral RNA synthesis of SARS-CoV-2, and its Beta and Delta variants at the concentration of 500 nM. Moreover, the human lung xenograft mouse model was used to investigate the anti-SARS-CoV-2 effect of Baf-A1. It was found that Baf-A1 significantly inhibited SARS-CoV-2 replication in the human lung xenografts by in situ hybridization and RT-PCR assays. Histopathological examination showed that Baf-A1 alleviated SARS-CoV-2-induced diffuse inflammatory infiltration of granulocytes and macrophages and alveolar endothelial cell death in human lung xenografts. In addition, immunohistochemistry analysis indicated that Baf-A1 decreased inflammatory exudation and infiltration in SARS-CoV-2-infected human lung xenografts. Therefore, Baf-A1 may be a candidate drug for SARS-CoV-2 treatment.


Asunto(s)
COVID-19 , Humanos , Animales , Ratones , Xenoinjertos , SARS-CoV-2 , Células Epiteliales Alveolares , Modelos Animales de Enfermedad
10.
Langmuir ; 39(46): 16336-16348, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37948692

RESUMEN

Liquid fuel is flammable and hazardous, and a pool fire is one of the most serious disasters. Therefore, it is important to develop high-performance firefighting agents. To synthesize aqueous film-forming foam (AFFF) formulations, two C6 short-chain fluorocarbon surfactants Capstone 1157 (FC1157) and sodium perfluorohexylethyl sulfonate (SF852) with different hydrophilic groups were introduced, and three hydrocarbon surfactants sodium dodecyl sulfate (SDS), decyl glucoside (APG0810), and coco glucoside (APG0814) were chosen. The AFFF formulations based on the short-chain fluorocarbon-hydrocarbon compounding system were developed, and the firefighting performance of the formulations was assessed according to the standard pool fire extinction test. The results indicated that amphoteric FC1157 was slightly more effective than anionic SF852 in extinguishing small-scale pool fires and could reduce heat flux more effectively than SF852. Fluorocarbon surfactant FC1157 has been shown to suppress large pool fires much better than SF852, possibly due to its higher foam stability, higher foaming property, lower dynamic surface tension, and lower bubble coarsening rate. Both formulations we studied were more effective than commercial AFFF formulations. A concentration of 0.1-0.3% of FC1157 in an AFFF solution was optimal for extinguishing high-boiling-point oil fires.

11.
Sleep Breath ; 27(3): 1099-1106, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36166132

RESUMEN

PURPOSE: Uvulopalatopharyngoplasty (UPPP) can aggravate lung inflammatory reactions in patients with obstructive sleep apnoea syndrome (OSAS). Dexmedetomidine (Dex) is a selective α-2 adrenoreceptor agonist that can alleviate lung injury. This study was designed to investigate the effects of Dex on oxygenation and inflammatory factors in patients undergoing UPPP in the early perioperative period. METHODS: Patients with OSAS undergoing UPPP were randomly allocated to the Dex Group or Control Group. Arterial blood gas analyses were performed, and the respiratory index (RI) and oxygenation index (OI) were calculated upon entering the operating room (T0) and immediately after surgery (T3). The inflammatory factors tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-10 (IL-10) were measured at T0 and T3. RESULTS: A total of 44 patients with OSAS were randomized. There was no significant difference in basic patient characteristics between the two groups. The preoperative RI and OI were not significantly different between the two groups, but they were altered immediately after surgery relative to the corresponding preoperative value (p < 0.05). Compared with the Control Group, the RI was significantly lower at T3 in the Dex Group (p < 0.001). However, there was no significant difference in the OI between the two groups (p = 0.128). The inflammatory factors TNF-α (p < 0.001) and IL-6 (p = 0.018) were lower, while IL-10 was higher in the Dex Group than in the Control Group (p < 0.001). CONCLUSION: Dexmedetomidine can improve the oxygenation and inhibit the inflammatory response in patients undergoing UPPP in the early perioperative period. TRIAL REGISTRATION: The present clinical study has been registered at Clinical Trials under number NCT03612440.


Asunto(s)
Dexmedetomidina , Humanos , Dexmedetomidina/uso terapéutico , Dexmedetomidina/farmacología , Interleucina-10 , Factor de Necrosis Tumoral alfa , Interleucina-6 , Estudios Prospectivos , Pulmón , Agonistas de Receptores Adrenérgicos alfa 2/farmacología
12.
Ren Fail ; 45(1): 2235431, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37470370

RESUMEN

Purpose: To investigate the clinical characteristics, pathological features, and outcomes of patients with antineutrophil cytoplasmic antibody (ANCA)-positive systemic lupus erythematosus (SLE) in northwest China.Methods: This retrospective study included 491 patients with SLE tested for ANCA antibodies and 171 patients with ANCA-associated vasculitis (AAV) as controls. Subgroup analysis limited to those with renal involvement, and by ANCA antibody subtype (PR3 vs MPO). To compare the proteinuria remission rates between ANCA-positive and ANCA-negative lupus nephritis (LN) groups, a logistic regression model was used for propensity score matching based on age, hemoglobin, and baseline estimated glomerular filtration rate (eGFR).Results: Compared to ANCA-negative SLE (n = 442), ANCA-positive SLE (n = 46) occur in older patients; however, these patients were younger than those with AAV (n = 167). The eGFR of patients with ANCA-positive LN (n = 25) was higher than that of patients having AAV with renal involvement (n = 56) but lower than that of patients with ANCA-negative LN (n = 163). Patients with SLE who had MPO-ANCA (n = 16) had higher levels of serum creatinine compared to those with PR3-ANCA (n = 30) (156.5 µmol/L vs. 45.5 µmol/L, p = 0.005). During the follow-up period, the remission rate of proteinuria in patients with ANCA-positive LN was lower than that of patients with ANCA-negative LN (50% vs. 75%, p = 0.008).Conclusion: Patients with ANCA-positive LN may have worse baseline renal function and lower protein remission rates compared to patients with ANCA-negative LN. ANCA titers should be regularly monitored throughout the follow-up period in patients with SLE, especially in cases of renal involvement.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Lupus Eritematoso Sistémico , Nefritis Lúpica , Humanos , Anciano , Anticuerpos Anticitoplasma de Neutrófilos , Estudios Retrospectivos , Lupus Eritematoso Sistémico/complicaciones , Nefritis Lúpica/complicaciones , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/complicaciones , Proteinuria/complicaciones , Peroxidasa
13.
Nano Lett ; 22(9): 3678-3684, 2022 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-35442043

RESUMEN

Inspired by electronic transistors, electric field gating has been adopted to manipulate ionic currents of smart nanofluidic devices. Here, we report a PNP nanofluidic bipolar junction transistor (nBJT) consisting of one polyaniline (PANI) layer sandwiched between two polyethylene terephthalate (PET) nanoporous membranes. The PNP nBJT exhibits three different responses of currents (quasi-linear, rectification, and sigmoid) due to the counterbalance between surface charge distribution and base voltage applied in the nanofluidic channels; thus, they can be switched by base voltage. Four operating modes (cutoff, active, saturation, and breakdown mode) occur in the collector response currents. Under optimal conditions, the PNP nBJT exhibits an average current gain of up to 95 in 100 mM KCl solution at a low base voltage of 0.2 V. The present nBJT is promising for fabrication of nanofluidic devices with logical-control functions for analysis of single molecules.


Asunto(s)
Nanoporos , Nanotecnología , Transporte Iónico , Iones , Transistores Electrónicos
14.
Molecules ; 28(6)2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36985606

RESUMEN

The key challenge in the practical application of electrochromic energy storage devices (EESDs) is the fabrication of high-performance electrode materials. Herein, we deposited K7[La(H2O)x(α2-P2W17O61)] (P2W17La) onto TiO2 nanowires (NW) to construct an NW-P2W17La nanocomposite using a layer-by-layer self-assembly method. In contrast to the pure P2W17La films, the nanocomposite exhibits enhanced electrochromic and electrochemical performance owing to the 3D sea-cucumber-like microstructure. An EESD using the NW-P2W17La film as the cathode exhibited outstanding electrochromic and energy storage properties, with high optical modulation (48.6% at 605 nm), high switching speeds (tcoloring = 15 s, tbleaching = 4 s), and high area capacitance (5.72 mF cm-2 at 0.15 mA cm-2). The device can reversibly switch between transparent and dark blue during the charge/discharge process, indicating that electrochromic contrast can be used as a quantitative indicator of the energy storage status.

15.
PLoS Pathog ; 16(10): e1008945, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33079954

RESUMEN

HBV is an enveloped DNA virus that replicates its DNA genome via reverse transcription of a pregenomic (pg) RNA intermediate in hepatocytes. Interestingly, HBV RNA can be detected in virus-like particles in chronic hepatitis B (CHB) patient serum and has been utilized as a biomarker for intrahepatic cccDNA activity in treated patients. However, the biogenesis and molecular characteristics of serum HBV RNA remain to be fully defined. In this study, we found that the encapsidated serum HBV RNA predominately consists of pgRNA, which are detergent- and ribonuclease-resistant. Through blocking HBV DNA replication without affecting pgRNA encapsidation by using the priming-defective HBV mutant Y63D or 3TC treatment, we demonstrated that the cell culture supernatant contains a large amount of pgRNA-containing nonenveloped capsids and a minor population of pgRNA-containing virions. The formation of pgRNA-virion requires both capsid assembly and viral envelope proteins, which can be inhibited by capsid assembly modulators and an envelope-knockout mutant, respectively. Furthermore, the pgRNA-virion utilizes the multivesicular body pathway for egress, in a similar way as DNA-virion morphogenesis. Northern blotting, RT-PCR, and 3' RACE assays revealed that serum/supernatant HBV pgRNA are mainly spliced and devoid of the 3'-terminal sequences. Furthermore, pgRNA-virion collected from cells treated with a reversible HBV priming inhibitor L-FMAU was unable to establish infection in HepG2-NTCP cells. In summary, serum HBV RNA is secreted in noninfectious virion-like particle as spliced and poly(A)-free pgRNA. Our study will shed light on the molecular biology of serum HBV RNA in HBV life cycle, and aid the development of serum HBV RNA as a novel biomarker for CHB diagnosis and treatment prognosis.


Asunto(s)
Virus de la Hepatitis B/patogenicidad , Hepatocitos/virología , ARN Viral/genética , Replicación Viral/genética , Cápside/metabolismo , Proteínas de la Cápside/metabolismo , ADN Viral/genética , Virus de la Hepatitis B/metabolismo , Humanos , Transcripción Reversa/genética , Ensamble de Virus/genética
16.
Clin Exp Nephrol ; 26(3): 216-225, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34665348

RESUMEN

BACKGROUND: Low-vacuum scanning electron microscopy (LV-SEM) is applied to diagnostic renal pathology. METHODS: To demonstrate the usefulness of LV-SEM and to clarify the optimal conditions of pathology samples, we investigated the alterations of glomerular basement membrane (GBM) and podocytes in control and experimental active Heymann nephritis (AHN) rats by LV-SEM. RESULTS: On week 15 following induction of AHN, spike formation on GBM with diffuse deposition of IgG and C3 developed. Using LV-SEM, diffuse crater-like protrusions were clearly noted three-dimensionally (3D) on surface of GBM in the same specimens of light microscopy (LM) and immunofluorescence (IF) studies only after removal coverslips or further adding periodic acid-silver methenamine (PAM) staining. These 3D ultrastructural findings of GBM surface could be detected in PAM-stained specimens by LV-SEM, although true GBM surface findings could not be obtained in acellular glomeruli, because some subepithelial deposits remained on surface of GBM. Adequate thickness was 1.5-5 µm for 10% formalin-fixed paraffin-embedded (FFPE) and 5-10 µm for the unfixed frozen sections. The foot processes and their effacement of podocytes could be observed by LV-SEM using 10%FFPE specimens with platinum blue (Pt-blue) staining or double staining of PAM and Pt-blue. These findings were obtained more large areas in 2.5% glutaraldehyde-fixed paraffin-embedded (2.5%GFPE) specimens. CONCLUSION: Our findings suggest that LV-SEM is a useful assessment tool for evaluating the alterations of GBM and podocytes in renal pathology using routine LM and IF specimens, as well as 2.5%GFPE specimens.


Asunto(s)
Membrana Basal Glomerular , Podocitos , Animales , Membrana Basal Glomerular/patología , Humanos , Riñón/ultraestructura , Microscopía Electrónica de Rastreo , Podocitos/patología , Ratas , Vacio
17.
World J Surg Oncol ; 20(1): 213, 2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35739505

RESUMEN

BACKGROUND: For patients with prior intra-abdominal surgery or multiple arteries, the retroperitoneal robot-assisted partial nephrectomy (rRAPN) is a better choice. The renal ventral tumor poses an additional challenge due to poor tumor exposure. This study is determined to assess the feasibility of an internal traction technique (ITT) in rRAPN for the management of renal ventral tumors. METHODS: From November 2019 to March 2021, a total of 28 patients with renal ventral tumor underwent rRAPN. All patients had prior abdominal surgery or multiple arteries. The ITT group (20 patients), which improved the tumor exposure by traction of the kidney with suture, was compared with the traditional technique group (8 patients) in terms of warm ischemia time, estimated blood loss and postoperative hospital stay, retroperitoneal drainage, R.E.N.A.L. score, and serum creatinine. Differences were considered significant when P < 0.05. RESULTS: All rRAPN surgeries were successful without conversion to radical nephrectomy or open partial nephrectomy. The warm ischemia time was lower in the ITT group (17.10 min vs. 24.63 min; P < 0.05). Estimated blood loss in the traditional technique group was 324.88 ± 79.42 mL, and in the ITT group, it was 117.45±35.25 mL (P < 0.05). No significant differences with regard to postoperative hospital stay, retroperitoneal drainage, R.E.N.A.L. score, and serum creatinine were observed between both groups. Surgical margins were negative and no intraoperative complications occurred in all the patients. After 10 months of follow-up, no recurrence or metastasis occurred in all cases. CONCLUSION: ITT is a feasible, safe, and valid procedure in rRAPN for renal ventral tumors. Application of ITT improved the exposure and reduces warm ischemic time in comparison with the conventional procedure.


Asunto(s)
Neoplasias Renales , Laparoscopía , Procedimientos Quirúrgicos Robotizados , Robótica , Creatinina , Humanos , Neoplasias Renales/patología , Laparoscopía/métodos , Nefrectomía/métodos , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados/efectos adversos , Procedimientos Quirúrgicos Robotizados/métodos , Tracción , Resultado del Tratamiento
18.
Ren Fail ; 44(1): 731-740, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35484851

RESUMEN

OBJECTIVE: To verify glomerular PLA2R antigen and serum PLA2R antibody expression in membranous nephropathy as well as to explore glomerular PLA2R efficacy in evaluating the prognosis of idiopathic membranous nephropathy (IMN) in the background of different serum anti-PLA2R levels. METHODS: We retrospectively analyzed 155 patients who were diagnosed with IMN by kidney biopsy. Patients were divided into six groups according to their serum PLA2R antibody or glomerular PLA2R antigen positiveness and the level of serum anti-PLA2R titer. Both clinical features and pathological characteristics were recorded, and the remission time was compared among groups. Correlation between clinical figures and the anti-PLA2R titer or semi-quantity of glomerular PLA2R antigen was detected. RESULTS: A positive correlation between time to partial remission and serum anti-PLA2R titer was found. Among patients with serum anti-PLA2R titer <150 RU/ml, there were shorter remission time in negative glomerular PLA2R antigen group compared with positive glomerular PLA2R antigen, and a positive correlation between time to complete remission and semi-quantity of glomerular PLA2R antigen was found. CONCLUSION: Both glomerular PLA2R antigen and serum anti-PLA2R play a role in disease presentation and prognosis in primary membranous nephropathy. Glomerular PLA2R antigen has a major role on disease prognosis when serum anti-PLA2R titer is less than 150RU/ml, while serum anti-PLA2R has predominant role in IMN prognosis when serum anti-PLA2R titer is above 150RU/ml.


Asunto(s)
Glomerulonefritis Membranosa , Autoanticuerpos , Biomarcadores , Femenino , Glomerulonefritis Membranosa/patología , Humanos , Masculino , Pronóstico , Estudios Retrospectivos
19.
Molecules ; 27(13)2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35807536

RESUMEN

Polyoxometalates (POMs) demonstrate potential for application in the development of integrated smart energy devices based on bifunctional electrochromic (EC) optical modulation and electrochemical energy storage. Herein, a nanocomposite thin film composed of a vanadium-substituted Dawson-type POM, i.e., K7[P2W17VO62]·18H2O, and TiO2 nanowires were constructed via the combination of hydrothermal and layer-by-layer self-assembly methods. Through scanning electron microscopy and energy-dispersive spectroscopy characterisations, it was found that the TiO2 nanowire substrate acts as a skeleton to adsorb POM nanoparticles, thereby avoiding the aggregation or stacking of POM particles. The unique three-dimensional core-shell structures of these nanocomposites with high specific surface areas increases the number of active sites during the reaction process and shortens the ion diffusion pathway, thereby improving the electrochemical activities and electrical conductivities. Compared with pure POM thin films, the composite films showed improved EC properties with a significant optical contrast (38.32% at 580 nm), a short response time (1.65 and 1.64 s for colouring and bleaching, respectively), an excellent colouration efficiency (116.5 cm2 C-1), and satisfactory energy-storage properties (volumetric capacitance = 297.1 F cm-3 at 0.2 mA cm-2). Finally, a solid-state electrochromic energy-storage (EES) device was fabricated using the composite film as the cathode. After charging, the constructed device was able to light up a single light-emitting diode for 20 s. These results highlight the promising features of POM-based EES devices and demonstrate their potential for use in a wide range of applications, such as smart windows, military camouflage, sensors, and intelligent systems.


Asunto(s)
Nanocables , Aniones , Electrodos , Nanocables/química , Polielectrolitos , Titanio , Vanadio
20.
Biochem Biophys Res Commun ; 544: 22-30, 2021 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-33516878

RESUMEN

Hyperglycemia-induced podocyte damage contributes to the onset of diabetic nephropathy, a severe complication of diabetes. Perilipin 5 (Plin5) exerts a vital role in numerous pathological conditions via affecting cell apoptosis, oxidative stress, and inflammation. However, whether Plin5 plays a role in regulating podocyte damage of diabetic nephropathy has not been fully determined. This work aimed to explore the role of Plin5 in mediating high glucose (HG)-induced injury of podocytes in vitro. Our results demonstrated that Plin5 expression was markedly decreased in mouse podocytes challenged with HG. Plin5 overexpression markedly suppressed HG-induced apoptosis, reactive oxygen species (ROS) production, and the pro-inflammatory response in podocytes. On the contrary, Plin5 silencing produced the opposite effects. Further mechanistic analysis demonstrated that Plin5 upregulation remarkably increased the levels of phospho-Akt and phospho-glycogen synthase kinase-3ß (GSK-3ß) in HG-exposed podocytes. Moreover, Plin5 overexpression increased the levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and enhanced the activation of Nrf2 signaling. Akt inhibition markedly blocked Plin5-mediated activation of Nrf2, while GSK-3ß inhibition reversed Plin5-silencing-induced suppressive effects on Nrf2 activation. Notably, Nrf2 suppression significantly blocked Plin5-mediated protective effects against HG-induced podocyte injury. In summary, our work indicates a vital role for Plin5 in protecting against HG-induced apoptosis, oxidative stress, and inflammation in podocytes via modulation of Akt/GSK-3ß/Nrf2 signaling. This study suggests that Plin5 may participate in modulating podocyte damage in diabetic nephropathy.


Asunto(s)
Apoptosis , Glucosa/toxicidad , Inflamación/tratamiento farmacológico , Enfermedades Renales/prevención & control , Estrés Oxidativo , Perilipina-5/farmacología , Podocitos/efectos de los fármacos , Animales , Células Cultivadas , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Inflamación/metabolismo , Inflamación/patología , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Ratones , Factor 2 Relacionado con NF-E2/metabolismo , Fosforilación , Podocitos/metabolismo , Podocitos/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Edulcorantes/toxicidad
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