Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 677
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
EMBO Rep ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026012

RESUMO

Genome transcription and replication of influenza A virus (FluA), catalyzed by viral RNA polymerase (FluAPol), are delicately controlled across the virus life cycle. A switch from transcription to replication occurring at later stage of an infection is critical for progeny virion production and viral non-structural protein NS2 has been implicated in regulating the switch. However, the underlying regulatory mechanisms and the structure of NS2 remained elusive for years. Here, we determine the cryo-EM structure of the FluAPol-NS2 complex at ~3.0 Å resolution. Surprisingly, three domain-swapped NS2 dimers arrange three symmetrical FluPol dimers into a highly ordered barrel-like hexamer. Further structural and functional analyses demonstrate that NS2 binding not only hampers the interaction between FluAPol and the Pol II CTD because of steric conflicts, but also impairs FluAPol transcriptase activity by stalling it in the replicase conformation. Moreover, this is the first visualization of the full-length NS2 structure. Our findings uncover key molecular mechanisms of the FluA transcription-replication switch and have implications for the development of antivirals.

2.
EMBO J ; 40(16): e107786, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34018203

RESUMO

Pangolins have been suggested as potential reservoir of zoonotic viruses, including SARS-CoV-2 causing the global COVID-19 outbreak. Here, we study the binding of two SARS-CoV-2-like viruses isolated from pangolins, GX/P2V/2017 and GD/1/2019, to human angiotensin-converting enzyme 2 (hACE2), the receptor of SARS-CoV-2. We find that the spike protein receptor-binding domain (RBD) of pangolin CoVs binds to hACE2 as efficiently as the SARS-CoV-2 RBD in vitro. Furthermore, incorporation of pangolin CoV RBDs allows entry of pseudotyped VSV particles into hACE2-expressing cells. A screen for binding of pangolin CoV RBDs to ACE2 orthologs from various species suggests a broader host range than that of SARS-CoV-2. Additionally, cryo-EM structures of GX/P2V/2017 and GD/1/2019 RBDs in complex with hACE2 show their molecular binding in modes similar to SARS-CoV-2 RBD. Introducing the Q498H substitution found in pangolin CoVs into the SARS-CoV-2 RBD expands its binding capacity to ACE2 homologs of mouse, rat, and European hedgehog. These findings suggest that these two pangolin CoVs may infect humans, highlighting the necessity of further surveillance of pangolin CoVs.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Betacoronavirus/fisiologia , Pangolins/virologia , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Substituição de Aminoácidos , Enzima de Conversão de Angiotensina 2/química , Animais , Sítios de Ligação , Células HEK293 , Ouriços/virologia , Especificidade de Hospedeiro , Humanos , Camundongos , Modelos Moleculares , Filogenia , Ligação Proteica , Conformação Proteica , Ratos , Glicoproteína da Espícula de Coronavírus/genética , Internalização do Vírus
3.
J Virol ; 98(5): e0045124, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38591877

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a wide range of hosts, including hippopotami, which are semi-aquatic mammals and phylogenetically closely related to Cetacea. In this study, we characterized the binding properties of hippopotamus angiotensin-converting enzyme 2 (hiACE2) to the spike (S) protein receptor binding domains (RBDs) of the SARS-CoV-2 prototype (PT) and variants of concern (VOCs). Furthermore, the cryo-electron microscopy (cryo-EM) structure of the SARS-CoV-2 PT S protein complexed with hiACE2 was resolved. Structural and mutational analyses revealed that L30 and F83, which are specific to hiACE2, played a crucial role in the hiACE2/SARS-CoV-2 RBD interaction. In addition, comparative and structural analysis of ACE2 orthologs suggested that the cetaceans may have the potential to be infected by SARS-CoV-2. These results provide crucial molecular insights into the susceptibility of hippopotami to SARS-CoV-2 and suggest the potential risk of SARS-CoV-2 VOCs spillover and the necessity for surveillance. IMPORTANCE: The hippopotami are the first semi-aquatic artiodactyl mammals wherein SARS-CoV-2 infection has been reported. Exploration of the invasion mechanism of SARS-CoV-2 will provide important information for the surveillance of SARS-CoV-2 in hippopotami, as well as other semi-aquatic mammals and cetaceans. Here, we found that hippopotamus ACE2 (hiACE2) could efficiently bind to the RBDs of the SARS-CoV-2 prototype (PT) and variants of concern (VOCs) and facilitate the transduction of SARS-CoV-2 PT and VOCs pseudoviruses into hiACE2-expressing cells. The cryo-EM structure of the SARS-CoV-2 PT S protein complexed with hiACE2 elucidated a few critical residues in the RBD/hiACE2 interface, especially L30 and F83 of hiACE2 which are unique to hiACE2 and contributed to the decreased binding affinity to PT RBD compared to human ACE2. Our work provides insight into cross-species transmission and highlights the necessity for monitoring host jumps and spillover events on SARS-CoV-2 in semi-aquatic/aquatic mammals.


Assuntos
Enzima de Conversão de Angiotensina 2 , Artiodáctilos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Humanos , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/genética , Artiodáctilos/virologia , Betacoronavirus/genética , Betacoronavirus/metabolismo , Sítios de Ligação , COVID-19/virologia , COVID-19/metabolismo , Microscopia Crioeletrônica , Ligação Proteica , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética
4.
J Virol ; 98(3): e0115723, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38305152

RESUMO

Pet golden hamsters were first identified being infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) delta variant of concern (VOC) and transmitted the virus back to humans in Hong Kong in January 2022. Here, we studied the binding of two hamster (golden hamster and Chinese hamster) angiotensin-converting enzyme 2 (ACE2) proteins to the spike protein receptor-binding domains (RBDs) of SARS-CoV-2 prototype and eight variants, including alpha, beta, gamma, delta, and four omicron sub-variants (BA.1, BA.2, BA.3, and BA.4/BA.5). We found that the two hamster ACE2s present slightly lower affinity for the RBDs of all nine SARS-CoV-2 viruses tested than human ACE2 (hACE2). Furthermore, the similar infectivity to host cells expressing hamster ACE2s and hACE2 was confirmed with the nine pseudotyped SARS-CoV-2 viruses. Additionally, we determined two cryo-electron microscopy (EM) complex structures of golden hamster ACE2 (ghACE2)/delta RBD and ghACE2/omicron BA.3 RBD. The residues Q34 and N82, which exist in many rodent ACE2s, are responsible for the lower binding affinity of ghACE2 compared to hACE2. These findings suggest that all SARS-CoV-2 VOCs may infect hamsters, highlighting the necessity of further surveillance of SARS-CoV-2 in these animals.IMPORTANCESARS-CoV-2 can infect many domestic animals, including hamsters. There is an urgent need to understand the binding mechanism of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants to hamster receptors. Herein, we showed that two hamster angiotensin-converting enzyme 2s (ACE2s) (golden hamster ACE2 and Chinese hamster ACE2) can bind to the spike protein receptor-binding domains (RBDs) of SARS-CoV-2 prototype and eight variants and that pseudotyped SARS-CoV-2 viruses can infect hamster ACE2-expressing cells. The binding pattern of golden hamster ACE2 to SARS-CoV-2 RBDs is similar to that of Chinese hamster ACE2. The two hamster ACE2s present slightly lower affinity for the RBDs of all nine SARS-CoV-2 viruses tested than human ACE2. We solved the cryo-electron microscopy (EM) structures of golden hamster ACE2 in complex with delta RBD and omicron BA.3 RBD and found that residues Q34 and N82 are responsible for the lower binding affinity of ghACE2 compared to hACE2. Our work provides valuable information for understanding the cross-species transmission mechanism of SARS-CoV-2.


Assuntos
Enzima de Conversão de Angiotensina 2 , Cricetulus , Microscopia Crioeletrônica , Especificidade de Hospedeiro , Mesocricetus , Animais , Cricetinae , Humanos , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/ultraestrutura , Linhagem Celular , COVID-19/virologia , Cricetulus/metabolismo , Cricetulus/virologia , Mesocricetus/metabolismo , Mesocricetus/virologia , Mutação , Animais de Estimação/metabolismo , Animais de Estimação/virologia , Ligação Proteica , SARS-CoV-2/química , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , SARS-CoV-2/ultraestrutura , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/ultraestrutura
5.
Nano Lett ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39373390

RESUMO

Domain orientation modulation and controlled doping of two-dimensional (2D) transition-metal dichalcogenides (TMDCs) are two pivotal tasks for synthesizing wafer-scale single crystals and boosting device performances. However, realizing two such targets and uncovering internal physical mechanisms remain daunting challenges. We develop an accurate Fe doping strategy, which enables domain orientation control and electron mobility improvement of monolayer MoS2. By tuning of the Fe dopant dosages, parallel steps with different heights are formed, which induce edge-nucleation of unidirectionally aligned monolayer MoS2. In parallel, Fe doping induces the down shift of the conduction band minimum of monolayer MoS2 and matches well with the work function of an electrode, which reduces Schottky barrier height and delivers ultralow contact resistance (561 Ω µm) and excellent electron mobility (37.5 cm2 V-1 s-1). The modulation mechanism is clarified by combining theory calculations and electronic structure characterizations. This work hereby provides a new paradigm for synthesizing wafer-scale 2D TMDC single crystals and constructing high-performance devices.

6.
Nano Lett ; 24(7): 2408-2414, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38329291

RESUMO

Two-dimensional (2D) heterostructures with ferromagnetism and ferroelectricity provide a promising avenue to miniaturize the device size, increase computational power, and reduce energy consumption. However, the direct synthesis of such eye-catching heterostructures has yet to be realized up to now. Here, we design a two-step chemical vapor deposition strategy to growth of Cr2S3/WS2 vertical heterostructures with atomically sharp and clean interfaces on sapphire. The interlayer charge transfer and periodic moiré superlattice result in the emergence of room-temperature ferroelectricity in atomically thin Cr2S3/WS2 vertical heterostructures. In parallel, long-range ferromagnetic order is discovered in 2D Cr2S3 via the magneto-optical Kerr effect technique with the Curie temperature approaching 170 K. The charge distribution variation induced by the moiré superlattice changes the ferromagnetic coupling strength and enhances the Curie temperature. The coexistence of ferroelectricity and ferromagnetism in 2D Cr2S3/WS2 vertical heterostructures provides a cornerstone for the further design of logic-in-memory devices to build new computing architectures.

7.
Biol Reprod ; 111(2): 406-413, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38582608

RESUMO

The aim of this study was to evaluate the role of angiotensin-converting enzyme 1 (ACE1) in H2O2-induced trophoblast cell injury and the potential molecular mechanisms. Oxidative stress was modeled by exposing HTR-8/SVneo cells to 200 µM H2O2. Western blot and real-time quantitative PCR methods were used to detect protein and mRNA expression level of ACE1 in chorionic villus tissue and trophoblast HTR-8/SVneo cell. Inhibition of ACE1 expression was achieved by transfection with small interfering RNA. Then flow cytometry, Cell Counting Kit-8, and Transwell assay was used to assess apoptosis, viability, and migration ability of the cells. Reactive oxygen species (ROS) were detected by fluorescent probes, and malondialdehyde (MDA), superoxide dismutase (SOD), and reduced glutathione (GSH) activities were determined by corresponding detection kits. Angiotensin-converting enzyme 1 expression was upregulated in chorionic villus tissue of patients with missed abortion (MA) compared with individuals with normal early pregnancy abortion. H2O2 induced elevated ACE1 expression in HTR-8/SVneo cells, promoted apoptosis, and inhibited cell viability and migration. Knockdown of ACE1 expression inhibited H2O2-induced effects to enhance cell viability and migration and suppress apoptosis. Additionally, H2O2 stimulation caused increased levels of ROS and MDA and decreased SOD and GSH activity in the cells, whereas knockdown of ACE1 expression led to opposite changes of these oxidative stress indicators. Moreover, knockdown of ACE1 attenuated the inhibitory effect of H2O2 on the Nrf2/HO-1 pathway. Angiotensin-converting enzyme 1 was associated with MA, and it promoted H2O2-induced injury of trophoblast cells through inhibiting the Nrf2 pathway. Therefore, ACE1 may serve as a potential therapeutic target for MA.


Assuntos
Aborto Retido , Peróxido de Hidrogênio , Peptidil Dipeptidase A , Trofoblastos , Humanos , Trofoblastos/metabolismo , Trofoblastos/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Feminino , Gravidez , Aborto Retido/genética , Aborto Retido/metabolismo , Apoptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Linhagem Celular , Espécies Reativas de Oxigênio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Adulto , Movimento Celular/efeitos dos fármacos
8.
PLoS Pathog ; 18(4): e1010446, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35377920

RESUMO

Host defense systems employ posttranslational modifications to protect against invading pathogens. Here, we found that protein inhibitor of activated STAT 1 (PIAS1) interacts with the nucleoprotein (NP), polymerase basic protein 1 (PB1), and polymerase basic protein 2 (PB2) of influenza A virus (IAV). Lentiviral-mediated stable overexpression of PIAS1 dramatically suppressed the replication of IAV, whereas siRNA knockdown or CRISPR/Cas9 knockout of PIAS1 expression significantly increased virus growth. The expression of PIAS1 was significantly induced upon IAV infection in both cell culture and mice, and PIAS1 was involved in the overall increase in cellular SUMOylation induced by IAV infection. We found that PIAS1 inhibited the activity of the viral RNP complex, whereas the C351S or W372A mutant of PIAS1, which lacks the SUMO E3 ligase activity, lost the ability to suppress the activity of the viral RNP complex. Notably, the SUMO E3 ligase activity of PIAS1 catalyzed robust SUMOylation of PB2, but had no role in PB1 SUMOylation and a minimal role in NP SUMOylation. Moreover, PIAS1-mediated SUMOylation remarkably reduced the stability of IAV PB2. When tested in vivo, we found that the downregulation of Pias1 expression in mice enhanced the growth and virulence of IAV. Together, our findings define PIAS1 as a restriction factor for the replication and pathogenesis of IAV.


Assuntos
Vírus da Influenza A , Proteínas Inibidoras de STAT Ativados , Sumoilação , Replicação Viral , Animais , Vírus da Influenza A/patogenicidade , Vírus da Influenza A/fisiologia , Camundongos , Proteínas Inibidoras de STAT Ativados/genética , Proteínas Inibidoras de STAT Ativados/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Virulência
9.
Chemistry ; 30(32): e202400700, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38625164

RESUMO

The sensitive and reliable nanozyme-based sensor enables the detection of low concentrations of H2O2 in biological microenvironments, it has potential applications as an in-situ monitoring platform for cellular H2O2 release. The uniformly dispersed bimetallic sulfide (Zn2SnS4) nanoflowers were synthesized via a one-pot hydrothermal method and the two kinds of metal ions can serve as morphology and structure directing agents for each other in the synthetic process. The nanoparticles were utilized as nanozyme materials to fabricate a novel electrochemical sensor, and it exhibits a distinct electrochemical response towards H2O2 with excellent stability and detection capability (with a minimum detection limit of 1.79 nM (S/N=3)), the excellent characteristics facilitate the precise detection of low concentrations of H2O2 in biological microenvironments. Use the macrophages differentiated from leukemia THP-1 cells as a representative sensing model, the sensor was successfully utilized for real-time monitoring of the release of H2O2 induced by living cells, which has significant potential applications in clinical diagnosis and cancer treatment.


Assuntos
Técnicas Eletroquímicas , Peróxido de Hidrogênio , Limite de Detecção , Sulfetos , Peróxido de Hidrogênio/química , Humanos , Técnicas Eletroquímicas/métodos , Sulfetos/química , Zinco/química , Células THP-1 , Macrófagos/metabolismo
10.
Arch Virol ; 169(11): 217, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39379633

RESUMO

Porcine epidemic diarrhea virus (PEDV) causes the third most important disease in the pig industry, after African swine fever and porcine reproductive and respiratory syndrome, and leads to illness or death of the entire litter, causing significant economic losses. In this study, three PEDV strains (HN-1, HN-2, and SC2023) were isolated from swine farms with suspected PEDV infections in Sichuan and Henan provinces. Phylogenetic analysis based on complete S gene sequences showed that all three strains belonged to the G2c subgroup. HN-1 adapted readily to cell culture, grew to a viral titer as high as 2 × 108 TCID50/mL in Vero cells, and caused the formation of large syncytia. We analyzed the amino acid sequence of the HN-1 isolate and found that its S1 subunit contained a three-amino-acid insertion (355KRL358). A seven-amino-acid-deletion (1377FEKVHVQ1383) in the S2 subunit resulted in the partial deletion of the endocytosis signal YxxΦ and the complete deletion of the endoplasmic reticulum retrieval signal (ERRS) KVHVQ in the cytoplasmic tail of the S protein. Consequently, HN-1 is predicted to be less pathogenic than its parent strain, an attribute that facilitates rapid cell-to-cell spread by enhancing syncytium formation. In addition, strain HN-1 was found to have the mutation 884-885SG→RR, which may favor adaptation to cell culture by providing new trypsin cleavage sites. These results suggest that HN-1 is a G2c subtype variant that adapts well to cell culture and can be used to study the adaptive mechanisms of PEDV and develop attenuated vaccines.


Assuntos
Infecções por Coronavirus , Filogenia , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Vírus da Diarreia Epidêmica Suína/genética , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Vírus da Diarreia Epidêmica Suína/classificação , Suínos , Células Vero , Chlorocebus aethiops , Doenças dos Suínos/virologia , Infecções por Coronavirus/virologia , Infecções por Coronavirus/veterinária , China , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Sequência de Aminoácidos
11.
Mol Biol Rep ; 51(1): 774, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904794

RESUMO

BACKGROUND: Olive is an evergreen tree of Oleaceae Olea with numerous bioactive components. While the anti-inflammatory properties of olive oil and the derivatives are well-documented, there remains a dearth of in-depth researches on the immunosuppressive effects of olive fruit water extract. This study aimed to elucidate the dose-effect relationship and underlying molecular mechanisms of olive fruit extract in mediating anti-inflammatory responses. METHODS AND RESULTS: The impacts of olive fruit extract on the release of nitric oxide (NO), tumor necrosis factor (TNF-α), interleukins-6 (IL-6) and reactive oxygen species (ROS) were assessed in RAW264.7 cells induced by lipopolysaccharide (LPS). For deeper understanding, the expression of genes encoding inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), TNF-α and IL-6 was quantitatively tested. Additionally, the expression patterns of MAPK and NF-κB pathways were further observed to analyze the action mechanisms. Results suggested that olive fruit extract (200, 500, 1000 µg/mL) markedly exhibited a dose-dependent reduction in the generation of NO, TNF-α, IL-6 and ROS, as well as the expression of correlative genes studied. The activation of ERK, JNK, p38, IκB-α and p65 were all suppressed when p65 nuclear translocation was further restricted by olive fruit extract in NF-κB and MAPK signal pathways. CONCLUSIONS: Olive fruit extract targeted imposing restrictions on the signal transduction of key proteins in NF-κB and MAPK pathways, and thereby lowered the level of inflammatory mediators, which put an enormous hindrance to inflammatory development. Accordingly, it is reasonable to consider olive fruit as a potent ingredient in immunomodulatory products.


Assuntos
Anti-Inflamatórios , Frutas , Lipopolissacarídeos , NF-kappa B , Óxido Nítrico , Olea , Extratos Vegetais , Espécies Reativas de Oxigênio , Transdução de Sinais , Animais , Olea/química , Camundongos , Células RAW 264.7 , Extratos Vegetais/farmacologia , Anti-Inflamatórios/farmacologia , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Frutas/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Óxido Nítrico/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Interleucina-6/metabolismo , Interleucina-6/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Ciclo-Oxigenase 2/metabolismo , Ciclo-Oxigenase 2/genética , Sobrevivência Celular/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo
12.
Jpn J Clin Oncol ; 54(9): 975-985, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-38941323

RESUMO

BACKGROUND: Sarcopenic obesity (SO) affects outcomes in various malignancies. However, its clinical significance in patients undergoing neoadjuvant chemotherapy (NAC) for locally advanced gastric cancer (LAGC) remains unclear. This study investigated the impact of pre- and post-NAC SO on postoperative morbidity and survival. METHODS: Data from 207 patients with LAGC, who underwent NAC followed by radical gastrectomy between January 2010 and October 2019, were reviewed. Skeletal muscle mass and visceral fat area were measured pre- and post-NAC using computed tomography to define sarcopenia and obesity, the coexistence of which was defined as SO. RESULTS: Among the patients, 52 (25.1%) and 38 (18.4%) developed SO before and after NAC, respectively. Both pre- (34.6%) and post- (47.4%) NAC SO were associated with the highest postoperative morbidity rates; however, only post-NAC SO was an independent risk factor for postoperative morbidity [hazard ratio (HR) = 9.550, 95% confidence interval (CI) = 2.818-32.369; P < .001]. Pre-NAC SO was independently associated with poorer 3-year overall [46.2% vs. 61.3%; HR = 1.258 (95% CI = 1.023-1.547); P = .049] and recurrence-free [39.3% vs. 55.4%; HR 1.285 (95% CI 1.045-1.579); P = .017] survival. CONCLUSIONS: Pre-NAC SO was an independent prognostic factor in patients with LAGC undergoing NAC; post-NAC SO independently predicted postoperative morbidity.


Assuntos
Gastrectomia , Terapia Neoadjuvante , Obesidade , Sarcopenia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/tratamento farmacológico , Masculino , Feminino , Pessoa de Meia-Idade , Obesidade/complicações , Idoso , Estudos Retrospectivos , Quimioterapia Adjuvante , Prognóstico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resultado do Tratamento , Adulto
13.
Curr Microbiol ; 81(11): 396, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39375231

RESUMO

Strain DM2021935T representing a novel Acinetobacter species was isolated from a spoiled bath lotion in Guangdong, China. Based on 16S rRNA gene phylogenetic analysis, strain DM2021935T was closely related to 'Acinetobacter thutiue' VNH17T, Acinetobacter junii CIP 64.5 T, and Acinetobacter tibetensis Y-23 T. Cells of strain DM2021935T were Gram-stain-negative, non-spore-forming, strictly aerobic, catalase-positive, oxidase-negative, α-hemolytic, and non-motile. Strain DM2021935T exhibited growth in 1-3% (w/v) NaCl at temperatures ranging from 4 to 37 °C and tolerated pH levels from 6.0 to 8.0. The predominant fatty acids in strain DM2021935T are C12:0, C16:0, C18:1 ω9c, and summed feature 3. Polar lipid profiles included glycolipids, phospholipids, phosphatidylethanolamine, and phosphatidyl-N-methylethanolamine. The identified respiratory quinones were ubiquinone Q-8 and Q-9. The genomic size of DM2021935T comprised 4.15 Mb, consisting of one chromosome (3,827,633 bp) and two plasmids (241,357 and 83,010 bp). The G + C content was 41.8%. The average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization values between strain DM2021935T and phylogenetically related type strains were below the species delineation thresholds (72.2-95.4, 53.1-87.0, and 20.4-66.4%, respectively). AntiSMASH analysis identified four gene clusters: non-ribosomal peptide synthetase, non-alpha poly-amino group acids, YcaO cyclodehydratase, and aryl polyene biosynthesis. Based on genotypic data, strain DM2021935T represents a novel species within the genus Acinetobacter. The proposed name for the novel species is Acinetobacter corruptisaponis sp. nov. (type strain DM2021935T = KCTC 92772 T = GDMCC 1.3703 T).


Assuntos
Acinetobacter , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Filogenia , RNA Ribossômico 16S , Acinetobacter/genética , Acinetobacter/classificação , Acinetobacter/isolamento & purificação , RNA Ribossômico 16S/genética , Ácidos Graxos/química , DNA Bacteriano/genética , China , Genoma Bacteriano , Análise de Sequência de DNA , Fosfolipídeos/análise
14.
Plant Dis ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39449349

RESUMO

During surveys conducted in 2020, severe symptoms associated with death and decline were observed on >30-year-old Metasequoia glyptostroboides (Chinese redwood) trees in the shelter-forests along Yangtze River in Jingzhou city, Hubei province, China. A previous study showed that Phytophthora acerina was one of the causal agents of the decline of the Chinese redwood. In this study, a total of 147 fungal isolates were obtained from the diseased roots and xylem of trunks of declining M. glyptostroboides trees. Through morphology and multi-locus phylogenetic analysis, these isolates were identified as eight species belonging to the genera Fusarium and Neocosmospora including F. fujikuroi, F. irregulare, F. odoratissimum, F. reticulatum, N. falciformis, N. keratoplastica, N. solani, and N. tonkinensis. Single inoculation and co-inoculation with P. acerina assays of these Fusarium and Neocosmospora species were then performed to test pathogenicity on three-year-old seedlings of M. glyptostroboides. Lesions (i.e., on seedling stems) caused by species of the genera Neocosmopora and Fusarium were smaller than those caused by P. acerina. Co-inoculation of F. fujikuroi and P. acerina, as well as the co-inoculation of F. reticulatum and P. acerina caused larger lesions than inoculations with P. acerina alone. All these species of Fusarium and Neocosmospora were shown to have the potential to be pathogenic to M. glyptostroboides. This study provided evidence that the decline of M. glyptostroboides in Jingzhou is a disease complex.

15.
J Craniofac Surg ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39329505

RESUMO

Large metacarpal and phalangeal bone defects are a hot topic for orthopedic surgeons due to its high clinical incidence, disability rate, and postsurgical amputation rate, along with its difficult treatment, long treatment course, high cost, and poor effect, all of which have a negative impact on the appearance and function of the patient's hands. There are currently a variety of treatment options for large metacarpal and phalangeal bone defects, each with its own benefits and drawbacks. However, there is no treatment method capable of perfectly resolving all the problems of patients with these defects. In this paper, the authors introduce several common plans for and progress of large metacarpal and phalangeal bone defect treatment.

16.
Angew Chem Int Ed Engl ; 63(43): e202411166, 2024 Oct 21.
Artigo em Alemão | MEDLINE | ID: mdl-39008335

RESUMO

A molecular editing reaction for converting pyrrole rings into benzene rings through a sequential pathway of Diels-Alder and cheletropic reactions was developed. The nitrogen atom in a N-bridged intermediate is eliminated in the form of N2O by a strain-releasing pathway, ultimately leading to the formation of substituted benzene and naphthalene derivatives.

17.
Small ; 19(38): e2302029, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37194986

RESUMO

Sodium-ion batteries (SIBs) have received increasing attention because of their appealing cell voltages and cost-effective features. However, the atom aggregation and electrode volume variation inevitably deteriorate the sodium storage kinetics. Here a new strategy is proposed to boost the lifetime of SIB by synthesizing sea urchin-like FeSe2 /nitrogen-doped carbon (FeSe2 /NC) composites. The robust FeN coordination hinders the Fe atom aggregation and accommodates the volume expansion, while the unique biomorphic morphology and high conductivity of FeSe2 /NC enhance the intercalation/deintercalation kinetics and shorten the ion/electron diffusion length. As expected, FeSe2 /NC electrodes deliver excellent half (387.6 mAh g-1 at 20.0 A g-1 after 56 000 cycles) and full (203.5 mAh g-1 at 1.0 A g-1 after 1200 cycles) cell performances. Impressively, an ultralong lifetime of SIB composed of FeSe2 /Fe3 Se4 /NC anode is uncovered with the cycle number exceeding 65 000. The sodium storage mechanism is clarified with the aid of density function theory calculations and in situ characterizations. This work hereby provides a new paradigm for enhancing the lifetime of SIB by constructing a unique coordination environment between active material and framework.

18.
PLoS Pathog ; 17(2): e1009336, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33571308

RESUMO

Posttranslational modifications, such as SUMOylation, play specific roles in the life cycle of invading pathogens. However, the effect of SUMOylation on the adaptation, pathogenesis, and transmission of influenza A virus (IAV) remains largely unknown. Here, we found that a conserved lysine residue at position 612 (K612) of the polymerase basic protein 1 (PB1) of IAV is a bona fide SUMOylation site. SUMOylation of PB1 at K612 had no effect on the stability or cellular localization of PB1, but was critical for viral ribonucleoprotein (vRNP) complex activity and virus replication in vitro. When tested in vivo, we found that the virulence of SUMOylation-defective PB1/K612R mutant IAVs was highly attenuated in mice. Moreover, the airborne transmission of a 2009 pandemic H1N1 PB1/K612R mutant virus was impaired in ferrets, resulting in reversion to wild-type PB1 K612. Mechanistically, SUMOylation at K612 was essential for PB1 to act as the enzymatic core of the viral polymerase by preserving its ability to bind viral RNA. Our study reveals an essential role for PB1 K612 SUMOylation in the pathogenesis and transmission of IAVs, which can be targeted for the design of anti-influenza therapies.


Assuntos
Vírus da Influenza A/patogenicidade , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/transmissão , RNA Viral/metabolismo , Sumoilação , Proteínas Virais/metabolismo , Replicação Viral , Animais , Cães , Feminino , Furões , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/virologia , RNA Viral/genética , Proteínas Virais/química , Proteínas Virais/genética , Ligação Viral
19.
Anticancer Drugs ; 34(8): 962-966, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36602434

RESUMO

INTRODUCTION: Currently, there are few reports of patients with locally advanced lung cancer achieving a clinical complete response by medical treatment. Preoperative neoadjuvant immunotherapy combined with chemotherapy is an option for patients with unresectable, locally advanced nonsmall cell lung cancer (NSCLC) which is of great potential, and may change traditional treatment paradigms. There are relatively few large-scale, high-quality randomized-controlled trials yet, and limitations such as short postoperative follow-up period and immature disease-free survival and overall survival data still persist. Thus, evidence-based medical evidence is urgently needed. It is worthy to explore the further treatment of patients who achieved complete response after initial treatment, though lacking of evidence by now. CASE PRESENTATION: We report a stage IIIA lung squamous cell carcinoma case who achieved a major pathologic remission after neoadjuvant treatment with tislelizumab and chemotherapy. CONCLUSION: Our case study contributes to the existing evidence on the feasibility, efficacy and safety of neoadjuvant immunotherapy combined with chemotherapy in locally advanced unresectable NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Terapia Neoadjuvante , Carcinoma de Células Escamosas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
20.
Antonie Van Leeuwenhoek ; 116(11): 1185-1195, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37704902

RESUMO

A Gram-positive, facultatively anaerobic, oval beaded-shape, oxidase-negative, and non-motile bacterium designated DM20194951T was isolated from a spoiled eye mask obtained from Guangdong, China. Based on the 16S rRNA gene sequence, phylogenetic analysis indicated that strain DM20194951T showed the highest sequence similarity (95.8%) to Fundicoccus ignavus WS4937T. Meanwhile, strain DM20194951T could be distinguished from the type strains in the genus Fundicoccus by distinct phenotypic and genotypic traits. Strain DM20194951T grew variably with 1-2% (w/v) NaCl and tolerated pH 6.0-10.0. Growth was observed from 28 to 37 °C. The diagnostic diamino acids in the cell-wall peptidoglycan consisted of aspartic and glutamic acids as well as alanine. The predominant fatty acids were C18:1 ω9c, C16:0, and C16:1 ω9c. In the polar lipid profile, two glycolipids, three phospholipids, one phosphatidylglycerol, and one diphosphatidylglycerol were found. No respiratory quinones were detected. The DM20194951T genome is 3.2 Mb in size and contains a G + C content of 38.1%. A gene cluster for lactococcin 972 family bacteriocin production was found in the DM20194951T genome. Based on morphological, genotypic, and phylogenetic data, strain DM20194951T should be considered to represent a novel species in the genus Fundicoccus, for which the name Fundicoccus culcitae sp. nov. is proposed with the type strain DM20194951T (= KCTC 43472T = GDMCC 1.3614T).

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA