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1.
PLoS Biol ; 20(8): e3001741, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35972936

RESUMEN

Mitochondrial DNA (mtDNA) mutations are often associated with incurable diseases and lead to detectable pathogenic variants in 1 out of 200 babies. Uncoupling of the inheritance of mtDNA and the nuclear genome by spindle transfer (ST) can potentially prevent the transmission of mtDNA mutations from mother to offspring. However, no well-established studies have critically assessed the safety of this technique. Here, using single-cell triple omics sequencing method, we systematically analyzed the genome (copy number variation), DNA methylome, and transcriptome of ST and control blastocysts. The results showed that, compared to that in control embryos, the percentage of aneuploid cells in ST embryos did not significantly change. The epiblast, primitive endoderm, and trophectoderm (TE) of ST blastocysts presented RNA expression profiles that were comparable to those of control blastocysts. However, the DNA demethylation process in TE cells of ST blastocysts was slightly slower than that in the control blastocysts. Collectively, our results suggest that ST seems generally safe for embryonic development, with a relatively minor delay in the DNA demethylation process at the blastocyst stage.


Asunto(s)
Blastocisto , Variaciones en el Número de Copia de ADN , Aneuploidia , Blastocisto/metabolismo , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Desarrollo Embrionario/genética , Femenino , Humanos , Embarazo
2.
Angew Chem Int Ed Engl ; 63(21): e202401973, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38520059

RESUMEN

The inherently huge volume expansion during Li uptake has hindered the use of Si-based anodes in high-energy lithium-ion batteries. While some pore-forming and nano-architecting strategies show promises to effectively buffer the volume change, other parameters essential for practical electrode fabrication, such as compaction density, are often compromised. Here we propose a new in situ Mg doping strategy to form closed-nanopore structure into a micron-sized SiOx particle at a high bulk density. The doped Mg atoms promote the segregation of O, so that high-density magnesium silicates form to generate closed nanopores. By altering the mass content of Mg dopant, the average radii (ranged from 5.4 to 9.7 nm) and porosities (ranged from 1.4 % to 15.9 %) of the closed pores are precisely adjustable, which accounts for volume expansion of SiOx from 77.8 % to 22.2 % at the minimum. Benefited from the small volume variation, the Mg-doped micron-SiOx anode demonstrates improved Li storage performance towards realization of a 700-(dis)charge-cycle, 11-Ah-pouch-type cell at a capacity retention of >80 %. This work offers insights into reasonable design of the internal structure of micron-sized SiOx and other materials that undergo conversion or alloying reactions with drastic volume change, to enable high-energy batteries with stable electrochemistry.

3.
Anal Chem ; 95(4): 2253-2259, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36638820

RESUMEN

Double spike (DS) method has been extensively used in determining stable isotope ratios of many elements. However, challenges remain in obtaining high-precision isotope data for ultra-trace elements owing to the limitations of instrumental signal-to-noise ratios and the systematics of precision of DS-based measurements. Here, the DS-standard addition (SA) (DSSA) technique is proposed to improve measurements of isotope compositions of ultra-trace elements in natural samples. According to the U-shaped relationship between DS measurement uncertainty and the spike/sample ratio, theoretical equations and an error propagation model (EPM) were constructed comprehensively. In our method, a spiked secondary standard solution with a high, precisely known spike/sample ratio is mixed with samples such that the mixtures have spike/sample ratios within the optimal range. The abundances of the samples relative to the added standards (sample fraction; fspl) and the samples' isotope ratios can then be obtained exactly using a standard DS data reduction routine and the isotope binary mixing model. The accuracy and precision of the DSSA approach were verified by measurements of cadmium and molybdenum isotopes at as low as 5 ng levels. Compared with traditional DS measurements, the sample size for isotope analysis is reduced to 1/6-1/5 of the original with no loss of measurement precision. The optimal mixing range fspl = 0.15-0.5 is recommended. The DSSA method can be extended to isotope measurement of more than 33 elements where the DS method is applicable, especially for the ultra-trace elements such as platinum group and rare earth element isotopes.

4.
Reprod Biomed Online ; 47(3): 103237, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37400320

RESUMEN

RESEARCH QUESTION: Can an automated sperm injection robot perform Automated Intracytoplasmic Sperm Injection (ICSIA) for use in human IVF? DESIGN: The ICSIA robot automated the sperm injection procedure, including injection pipette advancement, zona pellucida and oolemma penetration with piezo pulses, and pipette removal after sperm release. The robot was first tested in mouse, hamster and rabbit oocytes, and subsequently using discarded human oocytes injected with microbeads. A small clinical pilot trial was conducted with donor oocytes to study the feasibility of the robot in a clinical setting. The ICSIA robot was controlled by engineers with no micromanipulation experience. Results were compared with those obtained with manual ICSI conducted by experienced embryologists. RESULTS: The ICSIA robot demonstrated similar results to the manual procedure in the different animal models tested as well as in the pre-clinical validations conducted in discarded human oocytes. In the clinical validation, 13 out of 14 oocytes injected with ICSIA fertilized correctly versus 16 out of 18 in the manual control; eight developed into good-quality blastocysts versus 12 in the manual control; and four were diagnosed as chromosomally normal versus 10 euploid in the manual control. Three euploid blastocysts from the ICSIA robot group have been transferred into two recipients, which resulted in two singleton pregnancies and two babies born. CONCLUSIONS: The ICSIA robot showed high proficiency in injecting animal and human oocytes when operated by inexperienced personnel. The preliminary results obtained in this first clinical pilot trial are within key performance indicators.


Asunto(s)
Fertilización In Vitro , Inyecciones de Esperma Intracitoplasmáticas , Femenino , Humanos , Masculino , Embarazo , Fertilización , Fertilización In Vitro/métodos , Oocitos , Semen , Inyecciones de Esperma Intracitoplasmáticas/métodos , Espermatozoides
5.
Angew Chem Int Ed Engl ; 62(33): e202305988, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37339945

RESUMEN

Ether solvents with superior reductive stability promise excellent interphasial stability with high-capacity anodes while the limited oxidative resistance hinders their high-voltage operation. Extending the intrinsic electrochemical stability of ether-based electrolytes to construct stable-cycling high-energy-density lithium-ion batteries is challenging but rewarding. Herein, the anion-solvent interactions were concerned as the key point to optimize the anodic stability of the ether-based electrolytes and an optimized interphase was realized on both pure-SiOx anodes and LiNi0.8 Mn0.1 Co0.1 O2 cathodes. Specifically, the small-anion-size LiNO3 and tetrahydrofuran with high dipole moment to dielectric constant ratio realized strengthened anion-solvent interactions, which enhance the oxidative stability of the electrolyte. The designed ether-based electrolyte enabled a stable cycling performance over 500 cycles in pure-SiOx ||LiNi0.8 Mn0.1 Co0.1 O2 full cell, demonstrating its superior practical prospects. This work provides new insight into the design of new electrolytes for emerging high-energy density lithium-ion batteries through the regulation of interactions between species in electrolytes.

6.
J Environ Manage ; 324: 116311, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36162319

RESUMEN

The recirculating aquaculture system (RAS) has attracted much attention in China as a way to rapidly transform and upgrade aquaculture ponds to realize zero-emissions of pollutants in aquaculture tail water. Tail water purification ponds (TWPPs) play an important role in the treatment of aquaculture wastewater. However, until now, there have been few reports on the occurrence of antibiotics in RAS and the removal of antibiotics from the TWPPs of RAS. Therefore, this study focused on the occurrence of antibiotics in a typical ecological RAS. For comparison, the same measurements were simultaneously carried out in nearby open aquaculture ponds and rivers. The pollution level and spatial distribution of antibiotics in the RAS and the removal of antibiotics in the TWPPs were explored. The results showed that (1) eleven and twelve antibiotics were detected in water and sediment samples in the RAS, respectively, but no antibiotics were found in fish muscles and feed. Erythromycin (ERY), lincomycin (LIN), and ciprofloxacin (CFX) were the three main types of antibiotics found in water and sediment samples. (2) The TWPPs of the RAS can effectively remove antibiotics in aquaculture water. The antibiotic concentration in recirculating aquaculture ponds of the RAS was as high as 180 ng/L. After treatments in the TWPPs, the antibiotic concentration of aquaculture water decreased to 81.6 ng/L (3) The antibiotic concentrations in recirculating aquaculture ponds (25.2-180 ng/L) were lower than those in the nearby open aquaculture ponds (126-267.3 ng/L), and the concentration of antibiotics in the sediments of recirculating aquaculture ponds was up to 22.9 ng/g, while that in TWPPs was as high as 56.1 ng/g. In conclusion, the antibiotic residues in the RAS were low after antibiotics were banned in feed in China, and the removal of antibiotics in the TWPPs was more pronounced. Furthermore, cross-contamination was found between the RAS, surrounding open aquaculture ponds and the river, and the water supply of the RAS was likely to be the main contributor of antibiotics in the aquaculture environments. This study can help the government formulate discharge standards for antibiotics in aquaculture and also provide a reference for the transformation and upgrading of aquaculture ponds to achieve a zero-emission aquaculture mode.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Químicos del Agua , Animales , Antibacterianos/análisis , Contaminantes Químicos del Agua/análisis , Acuicultura , Estanques , Agua , China
7.
Zhongguo Zhong Yao Za Zhi ; 46(1): 206-213, 2021 Jan.
Artículo en Zh | MEDLINE | ID: mdl-33645072

RESUMEN

This paper was to investigate the effect of Huanglian Jiedu Decoction(HLJD) on ulcerative colitis(UC) in mice, and determine the effective components in plasma, and virtually screen its therapeutic target, and predict its mechanism. Sixty Balb/c mice were randomly divided into blank group, model group, mesalazine treatment group(0.3 g·kg~(-1)), and HLJD treatment groups(24.66, 12.33, 6.17 g·kg~(-1)). Excepted for the blank group, all the mice in HLJD and mesalazine treatment groups were gavage administration. All mice freely drank 2.5% DSS solution for seven days to induce UC. The disease activity index(DAI) was detected each day. At the end of the experiment, HE staining was used to observe the pathological changes in colon. The content of IL-1ß, IL-6 and TNF-α in colon were determined by ELISA. The effective components in plasma were determined by UPLC-Q-TOF-MS. The reverse docking in PharmMapper was used to screen the component targets. The disease targets of UC were collected by searching TTD, OMIM and GeneCards databases. The intersection of the component targets and disease targets was selected as the therapeutic targets. Then the therapeutic targets were imported into the STRING for GO and KEGG enrichment analysis. Discovery Studio was used to simulate the docking between the components and the targets. RESULTS:: showed that the DAI in the model group increased significantly(P<0.05), and the number of inflammatory cells and infiltration degree increased significantly compared with the blank group. The DAI in HLJD treatment group was significantly reduced(P<0.05), and the number and infiltration degree of inflammatory cells were reduced compared with the model group. The ELISA results showed that the levels of IL-1ß, IL-6 and TNF-α were increased significantly in the model group(P<0.01) compared with the blank group, and significantly down regulated in the HLJD treatment group(P<0.05) compared with the model group. After UPLC-Q-TOF-MS analyse, ten components were identified. The network pharmacology analysis showed that the action targets were significantly enriched in 129 of biological processes, such as response to organic substance, chemical and oxygen-containing compound, etc., as well as 16 of signal pathways, such as IL-17, TNF and hepatitis B signal pathways, were enriched too. The results of molecular docking showed that limonin, palmatine and berberine could bind to CASP3 and MMP9 by hydrogen bond. In conclusion, HLJD could alleviate the colonic mucosal inflammatory infiltration and mucosal damage in UC mice. The mechanism may be related to the anti-inflammatory effect on UC mice by reducing the levels of IL-1ß, IL-6 and TNF-α in colon through limonin, palmatine and berberine regulating IL-17 signal pathway and TNF signal pathway via CASP3 and MMP9 meditated.


Asunto(s)
Colitis Ulcerosa , Animales , Antiinflamatorios/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Colon , Sulfato de Dextran/uso terapéutico , Medicamentos Herbarios Chinos , Ratones , Simulación del Acoplamiento Molecular , Plasma
8.
Anal Chem ; 92(12): 8046-8050, 2020 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-32449350

RESUMEN

In this work, well-ordered platinum (Pt) nanocubes (NCs), with precise control on the size and the spatial arrangement, are synthesized from a microemulsion overgrowth in a block copolymer (BC) nanotemplate. The nanovials on this self-assembled BC template serve as microreactors for the reduction of the HCl/H2PtCl6 precursor and direct the ordered periodic arrangement of the reduced Pt nanoparticles (NPs). As the content of HCl increases from 0% to 25%, the Pt NPs evolve from quasi-spheres to NCs, for which the density functional theory (DFT) computation reveals that the different adsorption energies of Cl and HCl dominate this morphology transition. For their potential application in fuel cells, the electrochemical catalysis of the Pt NCs demonstrates a 2.8-fold mass activity in contrast to the commercial JM 40% catalyst at the same Pt loading in ethanol oxidation reaction (EOR) and a good stability of 2.2% ECSA loss over 10 000 CV cycling.

9.
BMC Biotechnol ; 19(1): 23, 2019 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-31014302

RESUMEN

BACKGROUND: The gene transduction efficiency of adenovirus to hematopoietic cells, especially T lymphocytes, is needed to be improved. The purpose of this study is to improve the transduction efficiency of T lymphocytes by using fiber-modified human adenovirus 5 (HAdV-5) vectors. RESULTS: Four fiber-modified human adenovirus 5 (HAdV-5) vectors were investigated to transduce hematopoietic cells. F35-EG or F11p-EG were HAdV-35 or HAdV-11p fiber pseudotyped HAdV-5, and HR-EG or CR-EG vectors were generated by incorporating RGD motif to the HI loop or to the C-terminus of F11p-EG fiber. All vectors could transduce more than 90% of K562 or Jurkat cells at an multiplicity of infection (MOI) of 500 viral particle per cell (vp/cell). All vectors except HR-EG could transduce nearly 90% cord blood CD34+ cells or 80% primary human T cells at the MOI of 1000, and F11p-EG showed slight superiority to F35-EG and CR-EG. Adenoviral vectors transduced CD4+ T cells a little more efficiently than they did to CD8+ T cells. These vectors showed no cytotoxicity at an MOI as high as 1000 vp/cell because the infected and uninfected T cells retained the same CD4/CD8 ratio and cell growth rate. CONCLUSIONS: HAdV-11p fiber pseudotyped HAdV-5 could effectively transduce human T cells when human EF1a promoter was used to control the expression of transgene, suggesting its possible application in T cell immunocellular therapy.


Asunto(s)
Adenovirus Humanos/genética , Técnicas de Transferencia de Gen/normas , Vectores Genéticos/genética , Linfocitos T/metabolismo , Proteínas de la Cola de los Virus/genética , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/virología , Proliferación Celular/genética , Terapia Genética/métodos , Células HL-60 , Humanos , Células Jurkat , Células K562 , Linfocitos T/virología , Transducción Genética/normas , Transgenes/genética , Células U937 , Proteínas de la Cola de los Virus/metabolismo
10.
Am J Pathol ; 188(4): 1043-1058, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29353058

RESUMEN

Coloboma, heart defect, atresia choanae, retarded growth and development, genital hypoplasia, ear anomalies/deafness (CHARGE) syndrome is a congenital disorder affecting multiple organs and mainly caused by mutations in CHD7, a gene encoding a chromatin-remodeling protein. Immunodeficiency and reduced T cells have been noted in CHARGE syndrome. However, the mechanisms underlying T lymphopenia are largely unexplored. Herein, we observed dramatic decrease of T cells in both chd7knockdown and knockout zebrafish embryos. Unexpectedly, hematopoietic stem and progenitor cells and, particularly, lymphoid progenitor cells were increased peripherally in nonthymic areas in chd7-deficient embryos, unlikely to contribute to the T-cell decrease. Further analysis demonstrated that both the organogenesis and homing function of the thymus were seriously impaired. Chd7 might regulate thymus organogenesis through modulating the development of both neural crest cell-derived mesenchyme and pharyngeal endoderm-derived thymic epithelial cells. The expression of foxn1, a central regulator of thymic epithelium, was remarkably down-regulated in the pharyngeal region in chd7-deficient embryos. Moreover, the T-cell reduction in chd7-deficient embryos was partially rescued by overexpressing foxn1, suggesting that restoring thymic epithelium may be a potential therapeutic strategy for treating immunodeficiency in CHARGE syndrome. Collectively, the results indicated that chd7 was critical for thymic development and T-lymphopenia in CHARGE syndrome may be mainly attributed to the defects of thymic organogenesis. The current finding may benefit the diagnosis and therapy of T lymphopenia and immunodeficiency in CHARGE syndrome.


Asunto(s)
ADN Helicasas/metabolismo , Proteínas de Unión al ADN/metabolismo , Organogénesis , Linfocitos T/citología , Timo/citología , Timo/crecimiento & desarrollo , Proteínas de Pez Cebra/metabolismo , Pez Cebra/metabolismo , Animales , Animales Modificados Genéticamente , Apoptosis/efectos de los fármacos , Secuencia de Bases , Proteínas Morfogenéticas Óseas/metabolismo , Región Branquial/efectos de los fármacos , Región Branquial/embriología , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Quimiocinas/metabolismo , ADN Helicasas/deficiencia , Proteínas de Unión al ADN/deficiencia , Embrión no Mamífero/metabolismo , Células Epiteliales/metabolismo , Factores de Transcripción Forkhead/metabolismo , Células Madre Hematopoyéticas/metabolismo , Morfolinos/farmacología , Mutación/genética , Cresta Neural/patología , Fenotipo , Transducción de Señal , Pez Cebra/embriología , Proteínas de Pez Cebra/deficiencia
11.
J Virol ; 91(6)2017 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-28077642

RESUMEN

Defensins are small antimicrobial peptides capable of neutralizing human adenovirus (HAdV) in vitro by binding capsid proteins and blocking endosomal escape of virus. In humans, the alpha defensin HD5 is produced by specialized epithelial cells of the gastrointestinal and genito-urinary tracts. Here, we demonstrate, using patient biopsy specimens, that HD5 is also expressed as an active, secreted peptide by epithelial ovarian and lung cancer cells in situ This finding prompted us to study the role of HD5 in infection and spread of replication-competent, oncolytic HAdV type 3 (HAdV3). HAdV3 produces large amounts of penton-dodecahedra (PtDd), virus-like particles, during replication. We have previously shown that PtDd are involved in opening epithelial junctions, thus facilitating lateral spread of de novo-produced virions. Here, we describe a second function of PtDd, namely, the blocking of HD5. A central tool to prove that viral PtDd neutralize HD5 and support spread of progeny virus was an HAdV3 mutant virus in which formation of PtDd was disabled (mut-Ad3GFP, where GFP is green fluorescent protein). We demonstrated that viral spread of mut-Ad3GFP was blocked by synthetic HD5 whereas that of the wild-type (wt) form (wt-Ad3GFP) was only minimally impacted. In human colon cancer Caco-2 cells, induction of cellular HD5 expression by fibroblast growth factor 9 (FGF9) significantly inhibited viral spread and progeny virus production of mut-Ad3GFP but not of wt-Ad3GFP. Finally, the ectopic expression of HD5 in tumor cells diminished the in vivo oncolytic activity of mut-Ad3GFP but not of wt-Ad3GFP. These data suggest a new mechanism of HAdV3 to overcome innate antiviral host responses. Our study has implications for oncolytic adenovirus therapy.IMPORTANCE Previously, it has been reported that human defensin HD5 inactivates specific human adenoviruses by binding to capsid proteins and blocking endosomal escape of virus. The central new findings described in our manuscript are the following: (i) the discovery of a new mechanism used by human adenovirus serotype 3 to overcome innate antiviral host responses that is based on the capacity of HAdV3 to produce subviral penton-dodecahedral particles that act as decoys for HD5, thus preventing the inactivation of virus progeny produced upon replication; (ii) the demonstration that ectopic HD5 expression in cancer cells decreases the oncolytic efficacy of a serotype 5-based adenovirus vector; and (iii) the demonstration that epithelial ovarian and lung cancers express HD5. The study improves our understanding of how adenoviruses establish infection in epithelial tissues and has implications for cancer therapy with oncolytic adenoviruses.


Asunto(s)
Adenovirus Humanos/inmunología , Células Epiteliales/inmunología , Células Epiteliales/virología , Evasión Inmune , Viroterapia Oncolítica , Virus Oncolíticos/inmunología , alfa-Defensinas/metabolismo , Biopsia , Células CACO-2 , Femenino , Humanos , Neoplasias Pulmonares/patología , Neoplasias Ováricas/patología
12.
Reprod Biomed Online ; 34(4): 361-368, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28385334

RESUMEN

Mutations in mitochondrial DNA (mtDNA) are maternally inherited and can cause fatal or debilitating mitochondrial disorders. The severity of clinical symptoms is often associated with the level of mtDNA mutation load or degree of heteroplasmy. Current clinical options to prevent transmission of mtDNA mutations to offspring are limited. Experimental spindle transfer in metaphase II oocytes, also called mitochondrial replacement therapy, is a novel technology for preventing mtDNA transmission from oocytes to pre-implantation embryos. Here, we report a female carrier of Leigh syndrome (mtDNA mutation 8993T > G), with a long history of multiple undiagnosed pregnancy losses and deaths of offspring as a result of this disease, who underwent IVF after reconstitution of her oocytes by spindle transfer into the cytoplasm of enucleated donor oocytes. A male euploid blastocyst wasobtained from the reconstituted oocytes, which had only a 5.7% mtDNA mutation load. Transfer of the embryo resulted in a pregnancy with delivery of a boy with neonatal mtDNA mutation load of 2.36-9.23% in his tested tissues. The boy is currently healthy at 7 months of age, although long-term follow-up of the child's longitudinal development remains crucial.


Asunto(s)
Heterocigoto , Enfermedad de Leigh/prevención & control , Terapia de Reemplazo Mitocondrial , Oocitos/ultraestructura , ADN Mitocondrial/química , Femenino , Fertilización In Vitro , Humanos , Enfermedad de Leigh/genética , Nacimiento Vivo , Herencia Materna , Mitocondrias , Donación de Oocito , Linaje , Embarazo , Diagnóstico Preimplantación , Análisis de Secuencia de ADN
13.
Biomed Environ Sci ; 29(3): 224-8, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27109134

RESUMEN

The nonstructural protein 1 (NS1) of influenza A virus, which is absent from the viral particle, but highly expressed in infected cells, strongly antagonizes the interferon (IFN)-mediated antiviral response. We engineered an NS1-expressing 293 (293-NS1) cell line with no response to IFN stimulation. Compared with the parental 293 cells, the IFN-nonresponsive 293-NS1 cells improved the growth capacity of various viruses, but the introduction of NS1 barely enhanced the propagation of Tahyna virus, a negative-strand RNA virus. In particular, fastidious enteric adenovirus that replicates poorly in 293 cells may grow more efficiently in 293-NS1 cells; thus, IFN-nonresponsive 293-NS1 cells might be of great value in diagnostic laboratories for the cultivation and isolation of human enteric adenoviruses.


Asunto(s)
Virus de la Influenza A/fisiología , Proteínas no Estructurales Virales/metabolismo , Cultivo de Virus/métodos , Replicación Viral/fisiología , Línea Celular , Regulación de la Expresión Génica , Células HEK293 , Humanos , Proteínas no Estructurales Virales/genética
14.
PLoS Pathog ; 9(10): e1003718, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24204268

RESUMEN

Human adenovirus serotypes Ad3, Ad7, Ad11, and Ad14 use the epithelial junction protein desmoglein 2 (DSG2) as a receptor for infection. During Ad infection, the fiber and penton base capsid proteins are produced in vast excess and form hetero-oligomers, called pentons. It has been shown for Ad3 that pentons self-assemble into penton-dodecahedra (PtDd). Our previous studies with recombinant purified Ad3 PtDd (produced in insect cells) showed that PtDd bind to DSG2 and trigger intracellular signaling resulting in the transient opening of junctions between epithelial cells. So far, a definitive proof for a function of Ad3 PtDd in the viral life cycle is elusive. Based on the recently published 3D structure of recombinant Ad3 PtDd, we generated a penton base mutant Ad3 vector (mu-Ad3GFP). mu-Ad3GFP is identical to its wild-type counterpart (wt-Ad3GFP) in the efficiency of progeny virus production; however, it is disabled in the production of PtDd. For infection studies we used polarized epithelial cancer cells or cell spheroids. We showed that in wt-Ad3GFP infected cultures, PtDd were released from cells before viral cytolysis and triggered the restructuring of epithelial junctions. This in turn facilitated lateral viral spread of de novo produced virions. These events were nearly absent in mu-Ad3GFP infected cultures. Our in vitro findings were consolidated in mice carrying xenograft tumors derived from human epithelial cancer cells. Furthermore, we provide first evidence that PtDd are also formed by another DSG2-interacting Ad serotype, the newly emerged, highly pathogenic Ad14 strain (Ad14p1). The central finding of this study is that a subgroup of Ads has evolved to generate PtDd as a strategy to achieve penetration into and dissemination in epithelial tissues. Our findings are relevant for basic and applied virology, specifically for cancer virotherapy.


Asunto(s)
Infecciones por Adenovirus Humanos/transmisión , Adenovirus Humanos/metabolismo , Células Epiteliales/virología , Uniones Intercelulares/virología , Virión/metabolismo , Infecciones por Adenovirus Humanos/genética , Infecciones por Adenovirus Humanos/metabolismo , Adenovirus Humanos/genética , Animales , Células Epiteliales/metabolismo , Células Epiteliales/patología , Células HeLa , Humanos , Uniones Intercelulares/metabolismo , Uniones Intercelulares/patología , Ratones , Neoplasias/metabolismo , Neoplasias/patología , Neoplasias/terapia , Viroterapia Oncolítica/métodos
15.
Zhongguo Zhong Yao Za Zhi ; 39(9): 1675-9, 2014 May.
Artículo en Zh | MEDLINE | ID: mdl-25095383

RESUMEN

OBJECTIVE: To observe the analgesic effect of triptolide (TP) of high, middle and low doses on rats with adjuvant arthritis (AA), and the expressions of inducible nitric oxide synthase (iNOS) and substance P (SP) in spinal dorsal horn and dorsal root ganglion (DRG) of corresponding sections, in order to discuss the possible mechanism for the analgesic effect of TP on rats with adjuvant arthritis. METHOD: Fifty SD rats were selected and randomly divided into the normal group (group A), the model group (group B), and TP low (group C), middle (group D), high (group E) dose groups. Except for the group A, all of the remaining groups were injected with 0.1 mL of Freund's complete adjuvant through their right rear toes to establish the model. At 14 d after the model establishment, rats in C, D and E groups were intraperitoneally injected with different doses of TP (0.1 mg x kg(-1) for the group C, 0.2 mg x kg(-1) for the group D, 0.4 mg x kg(-1) for the group E) once a day for 9 days. Then the 50% mechanical withdraw threshold (MWT) was determined. And the expressions of iNOS and SP in lumbar5 (L5) spinal dorsal horn and DRG were detected with the immunohistochemical method. RESULT: The 50% MWT of rats in the group B was significantly lower than that of the group A (P < 0.01). After being treated with TP, the Thermal withdrawal latencies of groups C, D and E were significantly higher than that of the group B (P < 0.01). TP could notably increase the MWT of AA rats, with a certain dose-effect relationship. The immunohistochemical results indicated that the iNOS and SP expressions significantly increased in the group B (P < 0.01), while the positive expression levels of iNOS and SP in groups C, D and E were significantly lower than that of the group B (P < 0.01), with a certain dose-effect relationship. CONCLUSION: TP shows a good analgesic effect on AA, and could inhibit the iNOS and SP expressions in spinal dorsal horn and DRG in rats with adjuvant arthritis, which may be one of action mechanisms for the analgesic effect of TP.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Diterpenos/farmacología , Ganglios Espinales/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo II/biosíntesis , Fenantrenos/farmacología , Médula Espinal/efectos de los fármacos , Sustancia P/biosíntesis , Animales , Antiinflamatorios no Esteroideos/farmacología , Artritis Experimental/metabolismo , Artritis Experimental/fisiopatología , Relación Dosis-Respuesta a Droga , Compuestos Epoxi/farmacología , Femenino , Ganglios Espinales/metabolismo , Inmunohistoquímica , Masculino , Dimensión del Dolor/métodos , Fitoterapia , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Médula Espinal/metabolismo , Factores de Tiempo , Resultado del Tratamiento , Tripterygium/química
16.
Zhong Yao Cai ; 37(11): 2047-50, 2014 Nov.
Artículo en Zh | MEDLINE | ID: mdl-26027130

RESUMEN

OBJECTIVE: To study the analgesic effect of Triptolide(TP) in rats with adjuvant and the possible mechanism. METHODS: Fifty healthy SD rats were randomly divided into normal control group (group A), model group (group B), and low(group C), middle (group D) and high(group E) dose TP treatment groups. Except the group A, each group of rats were reared by toe intradermal injection of 0. 1 mL Freund's complete adjuvant. After 14 days,rats in the C, D and E groups were taken different doses (0. 1 mg/kg group C, 0. 2mg/kg group D, and 0. 4 mg/kg group E) by intraperitoneal injection of TP for 9 days, and then thermal withdrawal latency and the expression of NMDAR1 and BSI-B4 binding sites in lumbar5 (L5) spinal dorsal horn and DRG were detected. RESULTS: Thermal withdrawal latency of rats in group B was significantly lower than that of group A (P <0. 01), while those in group C, D and E were significantly higher than those in group B (P <0. 05 or P <0. 01). TP increased the thermal pain threshold by a quantity-effect relationship; NMDAR-1 and BSI-B4 binding sites expression levels were significantly increased in group B than those in group A (P <0. 01), while those in group C, D and E were lower than those in group B. CONCLUSION: Analgesic effect of TP is related to reducing levels of expression of NMDAR1 and BSI-B4 binding sites in spinal dorsal horn and DRG in rats with adjuvant arthritis.


Asunto(s)
Analgésicos/farmacología , Artritis Experimental/tratamiento farmacológico , Diterpenos/farmacología , Ganglios Espinales/efectos de los fármacos , Dolor/tratamiento farmacológico , Fenantrenos/farmacología , Receptores de N-Metil-D-Aspartato/metabolismo , Animales , Artritis Experimental/metabolismo , Sitios de Unión , Compuestos Epoxi/farmacología , Adyuvante de Freund , Ganglios Espinales/metabolismo , Inyecciones Intraperitoneales , Dimensión del Dolor , Ratas , Ratas Sprague-Dawley , Asta Dorsal de la Médula Espinal/citología
17.
IEEE Trans Cybern ; 54(1): 401-414, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37028359

RESUMEN

Federated learning (FL) is a decentralized machine learning architecture, which leverages a large number of remote devices to learn a joint model with distributed training data. However, the system-heterogeneity is one major challenge in an FL network to achieve robust distributed learning performance, which comes from two aspects: 1) device-heterogeneity due to the diverse computational capacity among devices and 2) data-heterogeneity due to the nonidentically distributed data across the network. Prior studies addressing the heterogeneous FL issue, for example, FedProx, lack formalization and it remains an open problem. This work first formalizes the system-heterogeneous FL problem and proposes a new algorithm, called federated local gradient approximation (FedLGA), to address this problem by bridging the divergence of local model updates via gradient approximation. To achieve this, FedLGA provides an alternated Hessian estimation method, which only requires extra linear complexity on the aggregator. Theoretically, we show that with a device-heterogeneous ratio ρ , FedLGA achieves convergence rates on non-i.i.d. distributed FL training data for the nonconvex optimization problems with O ([(1+ρ)/√{ENT}] + 1/T) and O ([(1+ρ)√E/√{TK}] + 1/T) for full and partial device participation, respectively, where E is the number of local learning epoch, T is the number of total communication round, N is the total device number, and K is the number of the selected device in one communication round under partially participation scheme. The results of comprehensive experiments on multiple datasets indicate that FedLGA can effectively address the system-heterogeneous problem and outperform current FL methods. Specifically, the performance against the CIFAR-10 dataset shows that, compared with FedAvg, FedLGA improves the model's best testing accuracy from 60.91% to 64.44%.

18.
Math Biosci Eng ; 21(3): 3498-3518, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38549293

RESUMEN

Aspect-level sentiment analysis can provide a fine-grain sentiment classification for inferring the sentiment polarity of specific aspects. Graph convolutional network (GCN) becomes increasingly popular because its graph structure can characterize the words' correlation for extracting more sentiment information. However, the word distance is often ignored and cause the cross-misclassification of different aspects. To address the problem, we propose a novel dual GCN structure to take advantage of word distance, syntactic information, and sentiment knowledge in a joint way. The word distance is not only used to enhance the syntactic dependency tree, but also to construct a new graph with semantic knowledge. Then, the two kinds of word distance assisted graphs are fed into two GCNs for further classification. The comprehensive results on two self-collected Chinese datasets (MOOC comments and Douban book reviews) as well as five open-source English datasets, demonstrate that our proposed approach achieves higher classification accuracy than the state-of-the-art methods with up to 1.81x training acceleration.

19.
Curr Med Chem ; 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38362686

RESUMEN

Liver fibrosis, characterized by the overproduction of extracellular matrix proteins within liver tissue, poses a rising global health concern. However, no approved antifibrotic drugs are currently available, highlighting the critical need for understanding the molecular mechanisms of liver fibrosis. This knowledge could not only aid in developing therapies but also enable early intervention, enhance disease prediction, and improve our understanding of the interaction between various underlying conditions and the liver. Notably, natural products used in traditional medicine systems worldwide and demonstrating diverse biochemical and pharmacological activities are increasingly recognized for their potential in treating liver fibrosis. This review aims to comprehensively understand liver fibrosis, emphasizing the molecular mechanisms and advancements in exploring natural products' antifibrotic potential over the past five years. It also acknowledges the challenges in their development and seeks to underscore their potency in enhancing patient prognosis and reducing the global burden of liver disease.

20.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167220, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38718847

RESUMEN

Glioblastoma is one of the most challenging malignancies with high aggressiveness and invasiveness and its development and progression of glioblastoma highly depends on branched-chain amino acid (BCAA) metabolism. The study aimed to investigate effects of inhibition of BCAA metabolism with cytosolic branched-chain amino acid transaminase (BCATc) Inhibitor 2 on glioblastoma, elucidate its underlying mechanisms, and explore therapeutic potential of targeting BCAA metabolism. The expression of BCATc was upregulated in glioblastoma and BCATc Inhibitor 2 precipitated apoptosis both in vivo and in vitro with the activation of Bax/Bcl2/Caspase-3/Caspase-9 axis. In addition, BCATc Inhibitor 2 promoted K63-linkage ubiquitination of mitofusin 2 (Mfn2), which subsequently caused lysosomal degradation of Mfn2, and then oxidative stress, mitochondrial fission and loss of mitochondrial membrane potential. Furthermore, BCATc Inhibitor 2 treatment resulted in metabolic reprogramming, and significant inhibition of expression of ATP5A, UQCRC2, SDHB and COX II, indicative of suppressed oxidative phosphorylation. Moreover, Mfn2 overexpression or scavenging mitochondria-originated reactive oxygen species (ROS) with mito-TEMPO ameliorated BCATc Inhibitor 2-induced oxidative stress, mitochondrial membrane potential disruption and mitochondrial fission, and abrogated the inhibitory effect of BCATc Inhibitor 2 on glioblastoma cells through PI3K/AKT/mTOR signaling. All of these findings indicate suppression of BCAA metabolism promotes glioblastoma cell apoptosis via disruption of Mfn2-mediated mitochondrial dynamics and inhibition of PI3K/AKT/mTOR pathway, and suggest that BCAA metabolism can be targeted for developing therapeutic agents to treat glioblastoma.


Asunto(s)
Aminoácidos de Cadena Ramificada , Apoptosis , GTP Fosfohidrolasas , Glioblastoma , Estrés Oxidativo , Humanos , Estrés Oxidativo/efectos de los fármacos , Apoptosis/efectos de los fármacos , Glioblastoma/metabolismo , Glioblastoma/patología , GTP Fosfohidrolasas/metabolismo , Animales , Aminoácidos de Cadena Ramificada/metabolismo , Línea Celular Tumoral , Ratones , Proteínas Mitocondriales/metabolismo , Ubiquitina/metabolismo , Transducción de Señal/efectos de los fármacos , Masculino , Ubiquitinación/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
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