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1.
Cell ; 171(2): 267-268, 2017 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-28985557

RESUMO

The endoplasmic reticulum-associated degradation (ERAD) pathway facilitates the disposal of terminally misfolded proteins in the early secretory pathway yet spares folding intermediates from being destroyed. Zhang et al. report on a protein complex that acts as a guardian to protect these folding intermediates from being targeted for ERAD.


Assuntos
Degradação Associada com o Retículo Endoplasmático , Dobramento de Proteína , Animais , Retículo Endoplasmático , Proteínas , Via Secretória
2.
Proc Natl Acad Sci U S A ; 121(17): e2311075121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38625942

RESUMO

Voltage oscillation at subzero in sodium-ion batteries (SIBs) has been a common but overlooked scenario, almost yet to be understood. For example, the phenomenon seriously deteriorates the performance of Na3V2(PO4)3 (NVP) cathode in PC (propylene carbonate)/EC (ethylene carbonate)-based electrolyte at -20 °C. Here, the correlation between voltage oscillation, structural evolution, and electrolytes has been revealed based on theoretical calculations, in-/ex-situ techniques, and cross-experiments. It is found that the local phase transition of the Na3V2(PO4)3 (NVP) cathode in PC/EC-based electrolyte at -20 °C should be responsible for the oscillatory phenomenon. Furthermore, the low exchange current density originating from the high desolvation energy barrier in NVP-PC/EC system also aggravates the local phase transformation, resulting in severe voltage oscillation. By introducing the diglyme solvent with lower Na-solvent binding energy, the voltage oscillation of the NVP can be eliminated effectively at subzero. As a result, the high capacity retentions of 98.3% at -20 °C and 75.3% at -40 °C are achieved. The finding provides insight into the abnormal SIBs degradation and brings the voltage oscillation behavior of rechargeable batteries into the limelight.

3.
Proc Natl Acad Sci U S A ; 120(1): e2211927120, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36574698

RESUMO

The limited efficacy of the current antitumor microenvironment strategies is due in part to the poor understanding of the roles and relative contributions of the various tumor stromal cells to tumor development. Here, we describe a versatile in vivo anthrax toxin protein delivery system allowing for the unambiguous genetic evaluation of individual tumor stromal elements in cancer. Our reengineered tumor-selective anthrax toxin exhibits potent antiproliferative activity by disrupting ERK signaling in sensitive cells. Since this activity requires the surface expression of the capillary morphogenesis protein-2 (CMG2) toxin receptor, genetic manipulation of CMG2 expression using our cell-type-specific CMG2 transgenic mice allows us to specifically define the role of individual tumor stromal cell types in tumor development. Here, we established mice with CMG2 only expressed in tumor endothelial cells (ECs) and determined the specific contribution of tumor stromal ECs to the toxin's antitumor activity. Our results demonstrate that disruption of ERK signaling only within tumor ECs is sufficient to halt tumor growth. We discovered that c-Myc is a downstream effector of ERK signaling and that the MEK-ERK-c-Myc central metabolic axis in tumor ECs is essential for tumor progression. As such, disruption of ERK-c-Myc signaling in host-derived tumor ECs by our tumor-selective anthrax toxins explains their high efficacy in solid tumor therapy.


Assuntos
Células Endoteliais , Neoplasias , Camundongos , Animais , Células Endoteliais/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Transdução de Sinais , Antígenos de Bactérias/metabolismo , Neoplasias/genética , Microambiente Tumoral
4.
J Am Chem Soc ; 146(9): 6199-6208, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38394360

RESUMO

A reliable solid electrolyte interphase (SEI) on the metallic Zn anode is imperative for stable Zn-based aqueous batteries. However, the incompatible Zn-ion reduction processes, scilicet simultaneous adsorption (capture) and desolvation (repulsion) of Zn2+(H2O)6, raise kinetics and stability challenges for the design of SEI. Here, we demonstrate a tandem chemistry strategy to decouple and accelerate the concurrent adsorption and desolvation processes of the Zn2+ cluster at the inner Helmholtz layer. An electrochemically assembled perforative mesopore SiO2 interphase with tandem hydrophilic -OH and hydrophobic -F groups serves as a Janus mesopores accelerator to boost a fast and stable Zn2+ reduction reaction. Combining in situ electrochemical digital holography, molecular dynamics simulations, and spectroscopic characterizations reveals that -OH groups capture Zn2+ clusters from the bulk electrolyte and then -F groups repulse coordinated H2O molecules in the solvation shell to achieve the tandem ion reduction process. The resultant symmetric batteries exhibit reversible cycles over 8000 and 2000 h under high current densities of 4 and 10 mA cm-2, respectively. The feasibility of the tandem chemistry is further evidenced in both Zn//VO2 and Zn//I2 batteries, and it might be universal to other aqueous metal-ion batteries.

5.
Funct Integr Genomics ; 24(3): 108, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38773054

RESUMO

Sulfate transporter (SULTR) proteins are in charge of the transport and absorption on sulfate substances, and have been reported to play vital roles in the biological processes of plant growth and stress response. However, there were few reports of genome-wide identification and expression-pattern analysis of SULTRs in Hibiscus mutabilis. Gossypium genus is a ideal model for studying the allopolyploidy, therefore two diploid species (G. raimondii and G. arboreum) and two tetraploid species (G. hirsutum and G. barbadense) were chosen in this study to perform bioinformatic analyses, identifying 18, 18, 35, and 35 SULTR members, respectively. All the 106 cotton SULTR genes were utilized to construct the phylogenetic tree together with 11 Arabidopsis thaliana, 13 Oryza sativa, and 8 Zea mays ones, which was divided into Group1-Group4. The clustering analyses of gene structures and 10 conserved motifs among the cotton SULTR genes showed the consistent evolutionary relationship with the phylogenetic tree, and the results of gene-duplication identification among the four representative Gossypium species indicated that genome-wide or segment duplication might make main contributions to the expansion of SULTR gene family in cotton. Having conducted the cis-regulatory element analysis in promoter region, we noticed that the existing salicylic acid (SA), jasmonic acid (JA), and abscisic acid (ABA) elements could have influences with expression levels of cotton SULTR genes. The expression patterns of GhSULTR genes were also investigated on the 7 different tissues or organs and the developing ovules and fibers, most of which were highly expressed in root, stem, sepal, receptacel, ovule at 10 DPA, and fiber at 20 and 25 DPA. In addition, more active regulatory were observed in GhSULTR genes responding to multiple abiotic stresses, and 12 highly expressed genes showed the similar expression patterns in the quantitative Real-time PCR experiments under cold, heat, salt, and drought treatments. These findings broaden our insight into the evolutionary relationships and expression patterns of the SULTR gene family in cotton, and provide the valuable information for further screening the vital candidate genes on trait improvement.


Assuntos
Regulação da Expressão Gênica de Plantas , Gossypium , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Gossypium/genética , Gossypium/crescimento & desenvolvimento , Gossypium/metabolismo , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Família Multigênica , Genoma de Planta , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo
6.
BMC Plant Biol ; 24(1): 554, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877405

RESUMO

BACKGROUND: Epidermal patterning factor / -like (EPF/EPFL) gene family encodes a class of cysteine-rich secretory peptides, which are widelyfound in terrestrial plants.Multiple studies has indicated that EPF/EPFLs might play significant roles in coordinating plant development and growth, especially as the morphogenesis processes of stoma, awn, stamen, and fruit skin. However, few research on EPF/EPFL gene family was reported in Gossypium. RESULTS: We separately identified 20 G. raimondii, 24 G. arboreum, 44 G. hirsutum, and 44 G. barbadense EPF/EPFL genes in the 4 representative cotton species, which were divided into four clades together with 11 Arabidopsis thaliana, 13 Oryza sativa, and 17 Selaginella moellendorffii ones based on their evolutionary relationships. The similar gene structure and common motifs indicated the high conservation among the EPF/EPFL members, while the uneven distribution in chromosomes implied the variability during the long-term evolutionary process. Hundreds of collinearity relationships were identified from the pairwise comparisons of intraspecifc and interspecific genomes, which illustrated gene duplication might contribute to the expansion of cotton EPF/EPFL gene family. A total of 15 kinds of cis-regulatory elements were predicted in the promoter regions, and divided into three major categories relevant to the biological processes of development and growth, plant hormone response, and abiotic stress response. Having performing the expression pattern analyses with the basic of the published RNA-seq data, we found most of GhEPF/EPFL and GbEPF/EPFL genes presented the relatively low expression levels among the 9 tissues or organs, while showed more dramatically different responses to high/low temperature and salt or drought stresses. Combined with transcriptome data of developing ovules and fibers and quantitative Real-time PCR results (qRT-PCR) of 15 highly expressed GhEPF/EPFL genes, it could be deduced that the cotton EPF/EPFL genes were closely related with fiber development. Additionally, the networks of protein-protein interacting among EPF/EPFLs concentrated on the cores of GhEPF1 and GhEPF7, and thosefunctional enrichment analyses indicated that most of EPF/EPFLs participate in the GO (Gene Ontology) terms of stomatal development and plant epidermis development, and the KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways of DNA or base excision repair. CONCLUSION: Totally, 132 EPF/EPFL genes were identified for the first time in cotton, whose bioinformatic analyses of cis-regulatory elements and expression patterns combined with qRT-PCR experiments to prove the potential functions in the biological processes of plant growth and responding to abiotic stresses, specifically in the fiber development. These results not only provide comprehensive and valuable information for cotton EPF/EPFL gene family, but also lay solid foundation for screening candidate EPF/EPFL genes in further cotton breeding.


Assuntos
Gossypium , Família Multigênica , Proteínas de Plantas , Gossypium/genética , Gossypium/metabolismo , Gossypium/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Genes de Plantas , Estudo de Associação Genômica Ampla , Perfilação da Expressão Gênica , Mapas de Interação de Proteínas
7.
Small ; 20(22): e2311029, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38152924

RESUMO

Vanadium-based cathode materials have attracted great attention in aqueous zinc-ion batteries (AZIBs). However, the inferior ion transport and cyclic stability due to the strong Coulomb interaction between Zn2+ and the lattice limit their further application. In this work, CO2 molecules are in situ embedded in the interlayer structure of NH4V4O10 by decomposing excess H2C2O4·2H2O in the main framework, obtaining an ion-molecule co-confining NH4V4O10 for AZIB cathode material. The introduced CO2 molecules expanded the interlayer spacing of NH4V4O10, broadened the diffusion channel of Zn2+, and stabilized the structure of NH4V4O10 as the interlayer pillars together with NH 4 + ${\mathrm{NH}}_4^ + $ , which effectively improved the Zn2+ diffusion kinetics and cycle stability of the electrode. In addition, the binding between NH 4 + ${\mathrm{NH}}_4^ + $ and the host framework is stabilized via hydrogen bonds with CO2 molecules. NVO-CO2-0.8 exhibited excellent specific capacity (451.1 mAh g-1 at 2 A g-1), cycle stability (214.0 mAh g-1 at 10 A g-1 after 1000 cycles) and rate performance. This work provides new ideas and approaches for optimizing vanadium-based materials with high-performance AZIBs.

8.
Angew Chem Int Ed Engl ; 63(20): e202402987, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38436516

RESUMO

Zinc-based aqueous batteries (ZABs) are attracting extensive attention due to the low cost, high capacity, and environmental benignity of the zinc anode. However, their application is still hindered by the undesired zinc dendrites. Despite Zn-surface modification being promising in relieving dendrites, a thick separator (i.e. glass fiber, 250-700 µm) is still required to resist the dendrite puncture, which limits volumetric energy density of battery. Here, we pivot from the traditional interphase plus extra separator categories, proposing an all-in-one ligand buffer layer (ca. 20 µm) to effectively modulate the Zn2+ transfer and deposition behaviors proved by in situ electrochemical digital holography. Experimental characterizations and density functional theory simulations further reveal that the catechol groups in the buffer layer can accelerate the Zn2+ reduction reaction (ZRR) through the electron-donating p-π conjugation effect, decreasing the negative charge in the coordination environment. Without extra separators, the elaborated system endows low polarization below 28.2 mV, long lifespan of 4950 h at 5 mA cm-2 in symmetric batteries, and an unprecedented volumetric energy density of 99.2 Wh L-1 based on the whole pouch cells. The concomitantly "separator-free" and "dendrite-free" conjugation effect with an accelerated ZRR process could foster the progression of metallic anodes and benefit energetic aqueous batteries.

9.
J Am Chem Soc ; 145(44): 24284-24293, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37888942

RESUMO

Zinc metal-based aqueous batteries (ZABs) offer a sustainable, affordable, and safe energy storage alternative to lithium, yet inevitable dendrite formation impedes their wide use, especially under long-term and high-rate cycles. How the battery can survive after dendrite formation remains an open question. Here, we pivot from conventional Zn dendrite growth suppression strategies, introducing proactive dendrite-digesting chemistry via a mesoporous Ti3C2 MXene (MesoTi3C2)-wrapped polypropylene separator. Spectroscopic characterizations and electrochemical evaluation demonstrate that MesoTi3C2, acting as an oxidant, can revive the formed dead Zn0 dendrites into electroactive Zn2+ ions through a spontaneous redox process. Density functional theory reveals that the abundant edge-Ti-O sites in our MesoTi3C2 facilitate high oxidizability and electron transfer from Zn0 dendrites compared to their in-plane counterparts. The resultant asymmetrical cell demonstrates remarkable ultralong cycle life of 2200 h at a practical current of 5 mA cm-2 with a low overpotential (<50 mV). The study reveals the unexpected edge effect of mesoporous MXenes and uncovers a new proactive dendrite-digesting chemistry to survive ZABs, albeit with inevitable dendrite formation.

10.
Crit Rev Eukaryot Gene Expr ; 33(4): 13-23, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37183943

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most difficult to treat of all malignancies. Multimodality regimens provide only short-term symptomatic improvement with minor impact on survival, underscoring the urgent need for novel therapeutics and treatment strategies for PDAC. We screened out the highly expressed gene LAMC2 in PDAC tissues through the GEO online database, and further demonstrated that it is related to the poor prognosis of PDAC patients. Next, we investigated the effect of LAMC2 in the development and metastasis of PDAC by silencing LAMC2 expression in PDAC cells. The results showed that silencing of LAMC2 inhibited the proliferation, invasion and metastasis, and promoted apoptosis of PDAC cells, silencing of LAMC2 also reversed the epithelial mesenchymal transition (EMT) and suppressed the activation of NF-κB signaling pathway. Our results identify LAMC2 as a pivotal regulator of PDAC malignant progression, and its overexpression is sufficient to confer the characteristically aggressive clinical features of this disease.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , Transição Epitelial-Mesenquimal/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/genética , Transdução de Sinais/genética , Proliferação de Células/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Laminina/genética , Laminina/metabolismo , Neoplasias Pancreáticas
11.
Planta ; 258(4): 83, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37721598

RESUMO

Gene annotation is essential for genome-based studies. However, algorithm-based genome annotation is difficult to fully and correctly reveal genomic information, especially for species with complex genomes. Artemisia annua L. is the only commercial resource of artemisinin production though the content of artemisinin is still to be improved. Genome-based genetic modification and breeding are useful strategies to boost artemisinin content and therefore, ensure the supply of artemisinin and reduce costs, but better gene annotation is urgently needed. In this study, we manually corrected the newly released genome annotation of A. annua using second- and third-generation transcriptome data. We found that incorrect gene information may lead to differences in structural, functional, and expression levels compared to the original expectations. We also identified alternative splicing events and found that genome annotation information impacted identifying alternative splicing genes. We further demonstrated that genome annotation information and alternative splicing could affect gene expression estimation and gene function prediction. Finally, we provided a valuable version of A. annua genome annotation and demonstrated the importance of gene annotation in future research.


Assuntos
Artemisia annua , Artemisininas , Artemisia annua/genética , Processamento Alternativo/genética , Melhoramento Vegetal , Genômica
12.
J Am Chem Soc ; 144(26): 11767-11777, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35731994

RESUMO

Constructing hierarchical three-dimensional (3D) mesostructures with unique pore structure, controllable morphology, highly accessible surface area, and appealing functionality remains a great challenge in materials science. Here, we report a monomicelle interface confined assembly approach to fabricate an unprecedented type of 3D mesoporous N-doped carbon superstructure for the first time. In this hierarchical structure, a large hollow locates in the center (∼300 nm in diameter), and an ultrathin monolayer of spherical mesopores (∼22 nm) uniformly distributes on the hollow shells. Meanwhile, a small hole (4.0-4.5 nm) is also created on the interior surface of each small spherical mesopore, enabling the superstructure to be totally interconnected. Vitally, such interconnected porous supraparticles exhibit ultrahigh accessible surface area (685 m2 g-1) and good underwater aerophilicity due to the abundant spherical mesopores. Additionally, the number (70-150) of spherical mesopores, particle size (22 and 42 nm), and shell thickness (4.0-26 nm) of the supraparticles can all be accurately manipulated. Besides this spherical morphology, other configurations involving 3D hollow nanovesicles and 2D nanosheets were also obtained. Finally, we manifest the mesoporous carbon superstructure as an advanced electrocatalytic material with a half-wave potential of 0.82 V (vs RHE), equivalent to the value of the commercial Pt/C electrode, and notable durability for oxygen reduction reaction (ORR).

13.
Biochem J ; 478(24): 4203-4220, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34821356

RESUMO

SLC26A9, a member of the solute carrier protein family, transports chloride ions across various epithelia. SLC26A9 also associates with other ion channels and transporters linked to human health, and in some cases these heterotypic interactions are essential to support the biogenesis of both proteins. Therefore, understanding how this complex membrane protein is initially folded might provide new therapeutic strategies to overcome deficits in the function of SLC26A9 partners, one of which is associated with Cystic Fibrosis. To this end, we developed a novel yeast expression system for SLC26A9. This facile system has been used extensively with other ion channels and transporters to screen for factors that oversee protein folding checkpoints. As commonly observed for other channels and transporters, we first noted that a substantial fraction of SLC26A9 is targeted for endoplasmic reticulum associated degradation (ERAD), which destroys folding-compromised proteins in the early secretory pathway. We next discovered that ERAD selection requires the Hsp70 chaperone, which can play a vital role in ERAD substrate selection. We then created SLC26A9 mutants and found that the transmembrane-rich domain of SLC26A9 was quite stable, whereas the soluble cytosolic STAS domain was responsible for Hsp70-dependent ERAD. To support data obtained in the yeast model, we were able to recapitulate Hsp70-facilitated ERAD of the STAS domain in human tissue culture cells. These results indicate that a critical barrier to nascent membrane protein folding can reside within a specific soluble domain, one that is monitored by components associated with the ERAD machinery.


Assuntos
Antiporters/metabolismo , Degradação Associada com o Retículo Endoplasmático , Proteínas de Choque Térmico HSP70/metabolismo , Modelos Biológicos , Transportadores de Sulfato/metabolismo , Antiporters/genética , Células HEK293 , Proteínas de Choque Térmico HSP70/genética , Humanos , Domínios Proteicos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transportadores de Sulfato/genética
14.
BMC Vet Res ; 17(1): 22, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413356

RESUMO

BACKGROUND: Hemagglutinin is a major surface protein in influenza A virus (IAV), and HA2 is relative conserved among different IAVs. It will be meaningful to identify broad-spectrum epitopes based on the HA2 protein. RESULTS: Overlapping peptides of the HA2 protein of the H5N1 IAV A/Mallard/Huadong/S/2005 were synthesized and loaded on modified silica gel film to form a microarray, and antisera against different subtypes of IAVs were used to screen universal epitopes. The selected epitope was further confirmed by western blotting using anti-peptide immune serum and viruses rescued with amino acid substitution. The results showed that 485-FYHKCDNECME-495 of the H5 14th peptide in HA2 had broad-spectrum binding activity with antisera against H1, H3, H4, H5, H6, H7, H8, H9, and H10 subtype IAV. Substitution of amino acids (K or D) in rescued viruses resulted in decreased serum binding, indicating that they were critical residues for serum binding activity. In Immune Epitope Database, some epitopes containing 14-4 peptide were confirmed as MHC-II-restricted CD4 T cell epitope and had effects on releasing IL-2 or IFN. CONCLUSION: The identified epitope should be a novel universal target for detection and vaccine design and its ability to generate immune protection needs further exploration.


Assuntos
Antígenos Virais/imunologia , Epitopos/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Vírus da Influenza A/imunologia , Sequência de Aminoácidos , Animais , Antígenos Virais/química , Embrião de Galinha , Galinhas , Epitopos/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Soros Imunes , Virus da Influenza A Subtipo H5N1/química , Vírus da Influenza A/química , Peptídeos/química
15.
Appl Opt ; 60(15): 4299-4304, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34143116

RESUMO

A single-frequency (SF) fiber laser is widely applied in many fields. A superior ultra-narrow-bandwidth fiber filter, which consists of an in-series commercial common fiber Bragg grating (FBG) filters with a partial overlap in their reflection spectrum, is presented in this paper. The bandwidth of the filter with a center reflection wavelength of 1549.83 nm reaches 0.024 nm at 3 dB reflection, a remarkable reduction of approximately 300% by combination usage narrower than a single FBG used bandwidth. We also demonstrate a method to further narrowing of the filter bandwidth by increasing the usage times of filters, and the bandwidth can reach 0.0025 nm at 3 dB reflection. A long linear cavity single-frequency fiber laser with an entire cavity of 30 cm is implemented with the linewidth of 941 Hz at 3 dB, which is about 210% narrower than the previous record of SF fiber laser based on FBG filters in a linear cavity. This research may open a new door toward ultra-narrow-bandwidth filters and SF fiber lasers.

17.
Arch Virol ; 160(4): 917-27, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25616845

RESUMO

The pathogenicity and transmissibility of H9N2 influenza viruses has been widely investigated; however, few studies comparing the biological characteristics of H9N2 viruses isolated from different hosts have been performed. In this study, eight H9N2 viruses, isolated from chickens (Ck/F98, Ck/AH and Ck/TX), pigeons (Pg/XZ), quail/(Ql/A39), ducks (Dk/Y33) and swine (Sw/YZ and Sw/TZ) were selected, and their biological characteristics were determined. The results showed that all H9N2 viruses maintained a preference for both the avian- and human-type receptors, except for Sw/TZ, which had exclusive preference for the human-type receptor. The viruses replicated well in DF-1 and MDCK cells, whereas only three isolates, Ck/F98, Ck/TX and Sw/TZ, could replicate in A549 cells and also replicated in mouse lungs, resulting in body weight loss in mice. All H9N2 viruses were nonpathogenic to chickens and were detected in the trachea and lung tissues. The viruses were shed primarily by the oropharynx and were transmitted efficiently to naïve contact chickens. Our findings suggest that all H9N2 viruses from different hosts exhibit efficient replication and contact-transmission among chickens, and chickens serve as a good reservoir for the persistence and interspecies transmission of H9N2 influenza viruses.


Assuntos
Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Vírus da Influenza A Subtipo H9N2/fisiologia , Influenza Aviária/virologia , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/virologia , Animais , Linhagem Celular , Galinhas , Columbidae , Patos , Feminino , Especificidade de Hospedeiro , Humanos , Vírus da Influenza A Subtipo H9N2/classificação , Vírus da Influenza A Subtipo H9N2/genética , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/virologia , Filogenia , Aves Domésticas , Doenças das Aves Domésticas/virologia , Codorniz , Suínos
18.
Chemistry ; 20(5): 1341-8, 2014 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-24458914

RESUMO

The microporous metal-organic framework (MMOF) Zn4O(L1)2⋅9 DMF⋅9 H2O (1-H) and its functionalized derivatives Zn4O(L1-CH3)2⋅9 DMF⋅9 H2O (2-CH3) and Zn4O(L1-Cl)2⋅9 DMF⋅9 H2O (3-Cl) have been synthesized and characterized (H3L1=4-[N,N-bis(4-methylbenzoic acid)amino]benzoic acid, H3L1-CH3=4-[N,N-bis(4-methylbenzoic acid)amino]-2-methylbenzoic acid, H3L1-Cl=4-[N,N-bis(4-methylbenzoic acid)amino]-2-chlorobenzoic acid). Single-crystal X-ray diffraction analyses confirmed that the two functionalized MMOFs are isostructural to their parent MMOF, and are twofold interpenetrated three-dimensional (3D) microporous frameworks. All of the samples possess enduring porosity with Langmuir surface areas over 1950 cm(2) g(-1). Their pore volumes and surface areas decrease in the order 1-H>2-CH3 >3-Cl. Gas-adsorption studies show that the H2 uptakes of these samples are among the highest of the MMOFs (2.37 wt% for 3-Cl at 77 K and 1 bar), although their structures are interpenetrating. Furthermore, this work reveals that the adsorbate-adsorbent interaction plays a more important role in the gas-adsorption properties of these samples at low pressure, whereas the effects of the pore volumes and surface areas dominate the gas-adsorption properties at high pressure.

19.
Neural Netw ; 169: 44-56, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37857172

RESUMO

Complementary label learning (CLL) is an important problem that aims to reduce the cost of obtaining large-scale accurate datasets by only allowing each training sample to be equipped with labels the sample does not belong. Despite its promise, CLL remains a challenging task. Previous methods have proposed new loss functions or introduced deep learning-based models to CLL, but they mostly overlook the semantic information that may be implicit in the complementary labels. In this work, we propose a novel method, ComCo, which leverages a contrastive learning framework to assist CLL. Our method includes two key strategies: a positive selection strategy that identifies reliable positive samples and a negative selection strategy that skillfully integrates and leverages the information in the complementary labels to construct a negative set. These strategies bring ComCo closer to supervised contrastive learning. Empirically, ComCo significantly achieves better representation learning and outperforms the baseline models and the current state-of-the-art by up to 14.61% in CLL.


Assuntos
Leucemia Linfocítica Crônica de Células B , Humanos , Semântica
20.
J Int Med Res ; 52(3): 3000605241232968, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38460542

RESUMO

OBJECTIVE: To retrospectively compare the differences in the surgical efficacy and prognosis of laparoscopic pyeloplasty for hydronephrosis caused by symptomatic versus asymptomatic ureteropelvic junction obstruction (UPJO) in children and determine whether clinical symptoms affect the surgical outcome and prognosis. METHODS: Children who underwent laparoscopic pyeloplasty in our hospital from January 2018 to December 2022 were retrospectively analyzed. The children were divided into symptomatic and asymptomatic groups according to their main symptoms. The primary outcomes were the surgical success rate, change in renal parenchymal thickness, and change in renal pelvis anteroposterior diameter. The secondary outcomes were postoperative complications, reoperation rate, operative duration, intraoperative blood loss, and drainage tube indwelling time. RESULTS: In total, 224 children with UPJO were enrolled; 148 (66.1%) were symptomatic and 76 (33.9%) were asymptomatic. The symptomatic group showed a significantly greater mean change in renal parenchymal thickness, significantly higher surgical success rate, and significantly lower postoperative complication rate. CONCLUSIONS: In the present study, asymptomatic children had a lower surgical success rate, less postoperative imaging improvement, and more postoperative complications than symptomatic children. The presence or absence of clinical symptoms may affect the surgical outcome and prognosis.


Assuntos
Hidronefrose , Laparoscopia , Obstrução Ureteral , Humanos , Criança , Estudos Retrospectivos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Procedimentos Cirúrgicos Urológicos/métodos , Hidronefrose/diagnóstico por imagem , Hidronefrose/cirurgia , Hidronefrose/complicações , Obstrução Ureteral/cirurgia , Obstrução Ureteral/etiologia , Complicações Pós-Operatórias/cirurgia , Resultado do Tratamento
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