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1.
Sensors (Basel) ; 23(24)2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38139683

RESUMEN

Point cloud registration is widely used in autonomous driving, SLAM, and 3D reconstruction, and it aims to align point clouds from different viewpoints or poses under the same coordinate system. However, point cloud registration is challenging in complex situations, such as a large initial pose difference, high noise, or incomplete overlap, which will cause point cloud registration failure or mismatching. To address the shortcomings of the existing registration algorithms, this paper designed a new coarse-to-fine registration two-stage point cloud registration network, CCRNet, which utilizes an end-to-end form to perform the registration task for point clouds. The multi-scale feature extraction module, coarse registration prediction module, and fine registration prediction module designed in this paper can robustly and accurately register two point clouds without iterations. CCRNet can link the feature information between two point clouds and solve the problems of high noise and incomplete overlap by using a soft correspondence matrix. In the standard dataset ModelNet40, in cases of large initial pose difference, high noise, and incomplete overlap, the accuracy of our method, compared with the second-best popular registration algorithm, was improved by 7.0%, 7.8%, and 22.7% on the MAE, respectively. Experiments showed that our CCRNet method has advantages in registration results in a variety of complex conditions.

2.
Poult Sci ; 102(7): 102756, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37236035

RESUMEN

Egg production of hens is related to ovarian follicles development. The hierarchical follicle development accompanies the deposition of a large amount of yolk precursor. The aim of this study was to illustrate the effects of strain and age on yolk deposition and egg production. The experiment compared yolk synthesis, transport, and deposition in 3 groups of hens: one of a high-yield commercial hybrid laying breed (Jinghong No.1) in 2 stages (35 wk and 75 wk; JH35, JH75) and one of Chinese native breed (Lueyang Black-Boned chicken) at 35 wk (LY35). The results showed that the number of hierarchical follicles in JH35 and JH75 was significantly more than in LY35. At the same time, the yolk weight of the LY35 and JH75 was significantly higher than that of JH35. The expression of apolipoprotein A1 and apolipoprotein B genes in the liver of JH35 was higher than that of JH75. The expression of the very low-density lipoprotein receptor gene in the JH75 ovary was higher than that of the other 2 groups. The plasma concentrations of very low-density lipoprotein and vitellogenin were no significant difference among groups. The yolk deposition in hierarchical follicles based on the fat-soluble dyes measurement meant that the rate of yolk deposition of LY35 was lower than the other 2 groups. In most cases, the yolk deposition of JH75 was higher than that of the other groups, but the process showed greater fluctuation over time. These results meant that the rate and stability of yolk deposition played an essential role in affecting egg performance. In summary, both strain and age were related to egg production, but the 2 factors might impact yolk deposition and egg-laying performance differently. The egg performance may be affected by both yolk precursor synthesis and deposition for different strains, but it may be affected by yolk precursor deposition for the old laying hens.


Asunto(s)
Pollos , Ovario , Animales , Femenino , Pollos/genética , Oviposición , Lipoproteínas VLDL , Lipoproteínas LDL , Yema de Huevo , Alimentación Animal , Dieta
3.
Sensors (Basel) ; 23(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36904946

RESUMEN

Fringe projection profilometry (FPP) is prone to phase unwrapping error (PUE) due to phase noise and measurement conditions. Most of the existing PUE-correction methods detect and correct PUE on a pixel-by-pixel or partitioned block basis and do not make full use of the correlation of all information in the unwrapped phase map. In this study, a new method for detecting and correcting PUE is proposed. First, according to the low rank of the unwrapped phase map, multiple linear regression analysis is used to obtain the regression plane of the unwrapped phase, and thick PUE positions are marked on the basis of the tolerance set according to the regression plane. Then, an improved median filter is used to mark random PUE positions and finally correct marked PUE. Experimental results show that the proposed method is effective and robust. In addition, this method is progressive in the treatment of highly abrupt or discontinuous regions.

4.
Front Microbiol ; 12: 656353, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33868214

RESUMEN

Despite the availability of effective vaccines, hepatitis B virus (HBV) is still a major health issue, and approximately 350 million people have been chronically infected with HBV throughout the world. Interferons (IFNs) are the key molecules in the innate immune response that restrict several kinds of viral infections via the induction of hundreds of IFN-stimulated genes (ISGs). The objective of this study was to confirm if interferon alpha-inducible protein 27 (IFI27) as an ISG could inhibit HBV gene expression and DNA replication both in cell culture and in a mouse model. In human hepatoma cells, IFI27 was highly induced by the stimulation of IFN-alpha (IFN-α), and it potentiated the anti-HBV activity. The overexpression of IFI27 inhibited, while its silencing enhanced the HBV replication in HepG2 cell. However, the knocking out of IFI27 in HepG2 cells robustly increases the formation of viral DNA, RNA, and proteins. Detailed mechanistic analysis of the HBV genome showed that a sequence [nucleotide (nt) 1715-1815] of the EnhII/Cp promoter was solely responsible for viral inhibition. Similarly, the hydrodynamic injection of IFI27 expression constructs along with the HBV genome into mice resulted in a significant reduction in viral gene expression and DNA replication. In summary, our studies suggested that IFI27 contributed a vital role in HBV gene expression and replication and IFI27 may be a potential antiviral agent for the treatment of HBV.

5.
Front Immunol ; 12: 634937, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33868257

RESUMEN

Hepatitis B virus is an enveloped DNA virus, that infects more than three hundred and sixty million people worldwide and leads to severe chronic liver diseases. Interferon-alpha inducible protein 6 (IFI6) is an IFN-stimulated gene (ISG) whose expression is highly regulated by the stimulation of type I IFN-alpha that restricts various kinds of virus infections by targeting different stages of the viral life cycle. This study aims to investigate the antiviral activity of IFI6 against HBV replication and gene expression. The IFI6 was highly induced by the stimulation of IFN-α in hepatoma cells. The overexpression of IFI6 inhibited while knockdown of IFI6 elevated replication and gene expression of HBV in HepG2 cells. Further study determined that IFI6 inhibited HBV replication by reducing EnhII/Cp of the HBV without affecting liver enriched transcription factors that have significant importance in regulating HBV enhancer activity. Furthermore, deletion mutation of EnhII/Cp and CHIP analysis revealed 100 bps (1715-1815 nt) putative sites involved in IFI6 mediated inhibition of HBV. Detailed analysis with EMSA demonstrated that 1715-1770 nt of EnhII/Cp was specifically involved in binding with IFI6 and restricted EnhII/Cp promoter activity. Moreover, IFI6 was localized mainly inside the nucleus to involve in the anti-HBV activity of IFI6. In vivo analysis based on the hydrodynamic injection of IFI6 expression plasmid along with HBV revealed significant inhibition of HBV DNA replication and gene expression. Overall, our results suggested a novel mechanism of IFI6 mediated HBV regulation that could develop potential therapeutics for efficient HBV infection treatment.


Asunto(s)
Virus de la Hepatitis B/crecimiento & desarrollo , Hepatitis B/virología , Hígado/virología , Proteínas Mitocondriales/metabolismo , Replicación Viral , Animales , Sitios de Unión , Regulación Viral de la Expresión Génica , Células HEK293 , Células Hep G2 , Hepatitis B/genética , Hepatitis B/metabolismo , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/patogenicidad , Interacciones Huésped-Patógeno , Humanos , Interferón-alfa/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones Endogámicos C57BL , Proteínas Mitocondriales/genética , Regiones Promotoras Genéticas , Proteínas Virales/genética , Proteínas Virales/metabolismo
6.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-792958

RESUMEN

@# Objective: :To explore a novel chimeric antigen receptor (CAR)-T cell treatment to treat Multiple Myeloma (MM) via target B cell maturation antigen (BCMA). Methods: :A CAR-BCMA molecular was constructed based on mouse originated BCMA scFv, and was packaged into lentiviral vector and transfected into T cells from healthy donors to construct CAR-BCMA-T cells. The BCMApositive cell lines A549-BCMA, A549-BCMAOFP and K562-BCMA were constructed as target cells. Then, the CAR-BCMA-T cells were co-incubated with the constructed target cells and human myeloma U266 cells, and the cytotoxic effects of CAR-BCMA-T cells were evaluated via CCK-8 and FACS. Finally, the CAR-BCMA-T cells originated from MM patients were constructed, and its cytotoxicity against A549-BCMA were examined; in addition, the IFN-γ release level in CAR-BCMA-T cells was evaluated by ELISA and FACS. Results: After 11 days’incubation, the CAR-BCMA-T cells originated from healthy donors amplified 300 times with a positive rate of 43%. The BCMApositive target cell lines were constructed successfully. Under an effector : target ratio of 5:1, the killing rates of CARBCMA-T cells against A549-BCMA, K562-BCMA and U266 were about 80%, 60%, and 80%, respectively, which were significantly higher than those against BCMA negative cells; and the cytotoxicity was related to the BCMA expression level in target cells. What’ s more, at the effector : target ratio of 20:1, the CAR-BCMA-T cells originated from MM patients were demonstrated to exhibit a killing rate of more than 95% againstA549-BCMApositive cells, and produced large amount of IFN-γ. Conclusion: CAR-BCMA-T cells originated from both healthy and MM donors were successfully constructed, and they can effectively and specifically kill BCMA positive tumor cells.

7.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-821285

RESUMEN

@#[Abstract] Objective: To establish a chimeric antigen receptor(CAR)modified T cells specifically targeting CD19 molecule (CD19CAR-T cells) and to testify their in vitro killing effect on target cells. Methods: CD19-CAR fragments yielded by PCR were constructed into pCDH-GFP lentiviral vectors by molecular cloning technology. The packaged lentiviral particles were transducted into CD3+ T cells of donors. Transduction efficiency was measured by flow cytometry and PCR. The in vitro cytotoxicity of obtained CD19CAR-T cells against CD19+ Ramos cells was tested by 7-AAD staining. Results: The amplification folds of CD3+ T cells increased to (78.8± 23.2) folds after in vitro culture for 10 days, and about (58.3±5.4)% cells expressing GFP.About (57.4±9.3)% CD19+Ramos cells were specifically killed by the CD19-CAR-T cells in vitro at the E∶T ratio of 5∶1. Conclusion: This study successfully established an effective method for constructing and amplifying CD19-CAR-T cells in vitro, which showed profound efficiency and specific cytotoxity against CD19+ Ramos cells.And this report might provide an experimental evidence for clinical treatment of CD19+ B cell neoplasmas.

8.
J Gen Virol ; 97(12): 3368-3378, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27902332

RESUMEN

Cyclic GMP-AMP (cGAMP) synthase (cGAS) senses cytosolic DNA and catalyses synthesis of the second messenger cGAMP, which activates the downstream signalling adaptor protein STING, leading to the expression of type I interferons. Hepatitis B virus (HBV) is a small DNA virus, and the cGAS-STING pathway may inhibit HBV RNA synthesis and viral assembly in cell culture, but the exact roles of the cGAS pathway in the restriction of HBV replication in infection systems remain to be elucidated. In this study, replication of HBV was significantly inhibited both in cell culture and in vivo in a mouse model when the cGAS-STING pathway was activated by dsDNA or cGAMP. In contrast, the presence of enzymatically inactive cGAS mutant did not influence HBV replication. Moreover, knockdown of cGAS in human peripheral blood monocytes led to a higher level of intracellular HBV DNA. Collectively, our data indicate that the cGAS-STING pathway plays a role in the surveillance of HBV infection and may be exploited for development of novel anti-HBV strategies.


Asunto(s)
Virus de la Hepatitis B/fisiología , Hepatitis B/metabolismo , Proteínas de la Membrana/metabolismo , Nucleotidiltransferasas/metabolismo , Replicación Viral , Animales , Femenino , Hepatitis B/genética , Hepatitis B/virología , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Interacciones Huésped-Patógeno , Humanos , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos BALB C , Nucleotidiltransferasas/genética , Transducción de Señal , Ensamble de Virus
9.
Hepatology ; 64(2): 390-404, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27106262

RESUMEN

UNLABELLED: Hepatitis B viral infection is one of the leading causes of hepatocellular carcinoma (HCC) worldwide. Although several viral factors have been identified that may increase the risk for HCC development, the molecular mechanisms leading to the transformation of normal hepatocytes into cancer cells remain elusive. In this study, we demonstrated that the intracellular hepatitis B e antigen (HBeAg) and its precore precursors, but not their homologous core protein, could associate with NUMB and thereby impair the stability and transcriptional activity of tumor suppressor p53. HBeAg and its precursors could disrupt p53-NUMB and HDM2-NUMB interactions and tricomplex p53-HDM2-NUMB formation, inhibit the acetylation and translocation of p53 from cytosol to the nucleus, promote HDM2-mediated ubiquitination and degradation of p53, and suppress p53-dependent apoptosis. A xenograft tumorigenicity assay showed that expression of HBeAg and its precursors promoted carcinogenesis in a mouse model. Immunohistochemical analysis of the bioptic liver samples of HCC patients revealed that HBeAg positivity was associated with reduced transcriptional activity of p53. Taken together, the results suggest a role of intracellular HBeAg and its precursors in HCC development. CONCLUSION: HBeAg and its precursors promote HDM2-mediated degradation and impair transcriptional activity of p53 by interacting with NUMB, consequently contributing to HCC development. (Hepatology 2016;64:390-404).


Asunto(s)
Carcinoma Hepatocelular/virología , Antígenos e de la Hepatitis B/metabolismo , Neoplasias Hepáticas/virología , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Apoptosis , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Células HEK293 , Antígenos del Núcleo de la Hepatitis B/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Ratones , Ratones Desnudos , Células 3T3 NIH , Proteínas Proto-Oncogénicas c-mdm2/metabolismo
10.
J Gen Virol ; 96(8): 2252-2261, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25904148

RESUMEN

Hepatitis B virus (HBV) remains a global health threat as chronic HBV infection may lead to liver cirrhosis or cancer. Current antiviral therapies with nucleoside analogues can inhibit the replication of HBV, but do not disrupt the already existing HBV covalently closed circular DNA. The newly developed CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR-associated 9) system is a powerful tool to target cellular genome DNA for gene editing. In order to investigate the possibility of using the CRISPR/Cas9 system to disrupt the HBV DNA templates, we designed eight guide RNAs (gRNAs) that targeted the conserved regions of different HBV genotypes, which could significantly inhibit HBV replication both in vitro and in vivo. Moreover, the HBV-specific gRNA/Cas9 system could inhibit the replication of HBV of different genotypes in cells, and the viral DNA was significantly reduced by a single gRNA/Cas9 system and cleared by a combination of different gRNA/Cas9 systems.


Asunto(s)
Sistemas CRISPR-Cas , Marcación de Gen , Genoma Viral , Virus de la Hepatitis B/genética , Hepatitis B/virología , Animales , Secuencia de Bases , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Secuencia Conservada , Marcación de Gen/métodos , Virus de la Hepatitis B/fisiología , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Replicación Viral
11.
J Virol ; 89(8): 4345-55, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25653429

RESUMEN

UNLABELLED: Hepatitis B virus (HBV), a small enveloped DNA virus, chronically infects more than 350 million people worldwide and causes liver diseases from hepatitis to cirrhosis and liver cancer. Here, we report that hepatocyte nuclear factor 6 (HNF6), a liver-enriched transcription factor, can inhibit HBV gene expression and DNA replication. Overexpression of HNF6 inhibited, while knockdown of HNF6 expression enhanced, HBV gene expression and replication in hepatoma cells. Mechanistically, the SP2 promoter was inhibited by HNF6, which partly accounts for the inhibition on S mRNA. Detailed analysis showed that a cis element on the HBV genome (nucleotides [nt] 3009 to 3019) was responsible for the inhibition of the SP2 promoter by HNF6. Moreover, further analysis showed that HNF6 reduced viral pregenomic RNA (pgRNA) posttranscriptionally via accelerating the degradation of HBV pgRNA independent of La protein. Furthermore, by using truncated mutation experiments, we demonstrated that the N-terminal region of HNF6 was responsible for its inhibitory effects. Importantly, introduction of an HNF6 expression construct with the HBV genome into the mouse liver using hydrodynamic injection resulted in a significant reduction in viral gene expression and DNA replication. Overall, our data demonstrated that HNF6 is a novel host factor that can restrict HBV replication via both transcriptional and posttranscriptional mechanisms. IMPORTANCE: HBV is a major human pathogen whose replication is regulated by host factors. Liver-enriched transcription factors are critical for many liver functions, including metabolism, development, and cell proliferation, and some of them have been shown to regulate HBV gene expression or replication in different manners. In this study, we showed that HNF6 could inhibit the gene expression and DNA replication of HBV via both transcriptional and posttranscriptional mechanisms. As HNF6 is differentially expressed in men and women, the current results may suggest a role of HNF6 in the gender dimorphism of HBV infection.


Asunto(s)
Replicación del ADN/genética , Regulación Viral de la Expresión Génica/genética , Virus de la Hepatitis B/metabolismo , Factor Nuclear 6 del Hepatocito/metabolismo , Caracteres Sexuales , Animales , Northern Blotting , Western Blotting , Línea Celular Tumoral , Cartilla de ADN/genética , Femenino , Vectores Genéticos/genética , Células HEK293 , Virus de la Hepatitis B/genética , Factor Nuclear 6 del Hepatocito/genética , Humanos , Inmunohistoquímica , Luciferasas , Masculino , Ratones , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Transfección/métodos
12.
PLoS One ; 9(3): e91658, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24618592

RESUMEN

Nuclear factor-κB (NF-κB) plays a central role in the regulation of diverse biological processes, including immune responses, development, cell growth, and cell survival. To establish persistent infection, many viruses have evolved strategies to evade the host's antiviral immune defenses. In the case of hepatitis B virus (HBV), which can cause chronic infection in the liver, immune evasion strategies used by the virus are not fully understood. It has recently been reported that the polymerase of HBV (Pol) inhibits interferon-ß (IFN-ß) activity by disrupting the interaction between IKKε and the DDX3. In the current study, we found that HBV Pol suppressed NF-κB signaling, which can also contribute to IFN-ß production. HBV Pol did not alter the level of NF-κB expression, but it prevented NF-κB subunits involved in both the canonical and non-canonical NF-κB pathways from entering the nucleus. Further experiments demonstrated that HBV Pol preferentially suppressed the activity of the IκB kinase (IKK) complex by disrupting the association of IKK/NEMO with Cdc37/Hsp90, which is critical for the assembly of the IKK complex and recruitment of the IKK complex to the tumor necrosis factor type 1 receptor (TNF-R1). Furthermore, we found that HBV Pol inhibited the NF-κB-mediated transcription of target genes. Taken together, it is suggested that HBV Pol could counteract host innate immune responses by interfering with two distinct signaling pathways required for IFN-ß activation. Our studies therefore shed light on a potential therapeutic target for persistent infection with HBV.


Asunto(s)
Productos del Gen pol/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Virus de la Hepatitis B/metabolismo , Quinasa I-kappa B/metabolismo , FN-kappa B/metabolismo , Transducción de Señal , Línea Celular , Núcleo Celular/metabolismo , Expresión Génica , Productos del Gen pol/genética , Humanos , Fosforilación , Unión Proteica , Transporte de Proteínas , Proteolisis , Transcripción Genética , Transfección
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