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1.
Cell ; 169(2): 243-257.e25, 2017 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-28388409

RESUMO

Of all known cultured stem cell types, pluripotent stem cells (PSCs) sit atop the landscape of developmental potency and are characterized by their ability to generate all cell types of an adult organism. However, PSCs show limited contribution to the extraembryonic placental tissues in vivo. Here, we show that a chemical cocktail enables the derivation of stem cells with unique functional and molecular features from mice and humans, designated as extended pluripotent stem (EPS) cells, which are capable of chimerizing both embryonic and extraembryonic tissues. Notably, a single mouse EPS cell shows widespread chimeric contribution to both embryonic and extraembryonic lineages in vivo and permits generating single-EPS-cell-derived mice by tetraploid complementation. Furthermore, human EPS cells exhibit interspecies chimeric competency in mouse conceptuses. Our findings constitute a first step toward capturing pluripotent stem cells with extraembryonic developmental potentials in culture and open new avenues for basic and translational research. VIDEO ABSTRACT.


Assuntos
Técnicas de Cultura de Células/métodos , Células-Tronco Pluripotentes/citologia , Animais , Blastocisto/citologia , Linhagem Celular , Quimera/metabolismo , Dimetideno/farmacologia , Humanos , Indicadores e Reagentes/química , Camundongos , Minociclina/química , Minociclina/farmacologia , Células-Tronco Pluripotentes/efeitos dos fármacos , Poli(ADP-Ribose) Polimerase-1/metabolismo
2.
Nature ; 605(7909): 325-331, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35418683

RESUMO

Cellular reprogramming can manipulate the identity of cells to generate the desired cell types1-3. The use of cell intrinsic components, including oocyte cytoplasm and transcription factors, can enforce somatic cell reprogramming to pluripotent stem cells4-7. By contrast, chemical stimulation by exposure to small molecules offers an alternative approach that can manipulate cell fate in a simple and highly controllable manner8-10. However, human somatic cells are refractory to chemical stimulation owing to their stable epigenome2,11,12 and reduced plasticity13,14; it is therefore challenging to induce human pluripotent stem cells by chemical reprogramming. Here we demonstrate, by creating an intermediate plastic state, the chemical reprogramming of human somatic cells to human chemically induced pluripotent stem cells that exhibit key features of embryonic stem cells. The whole chemical reprogramming trajectory analysis delineated the induction of the intermediate plastic state at the early stage, during which chemical-induced dedifferentiation occurred, and this process was similar to the dedifferentiation process that occurs in axolotl limb regeneration. Moreover, we identified the JNK pathway as a major barrier to chemical reprogramming, the inhibition of which was indispensable for inducing cell plasticity and a regeneration-like program by suppressing pro-inflammatory pathways. Our chemical approach provides a platform for the generation and application of human pluripotent stem cells in biomedicine. This study lays foundations for developing regenerative therapeutic strategies that use well-defined chemicals to change cell fates in humans.


Assuntos
Diferenciação Celular , Reprogramação Celular , Células-Tronco Pluripotentes Induzidas , Linhagem da Célula , Humanos , Células-Tronco Pluripotentes Induzidas/citologia
3.
Nat Methods ; 19(3): 331-340, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35228726

RESUMO

Targeted insertion of large DNA fragments holds great potential for treating genetic diseases. Prime editors can effectively insert short fragments (~44 bp) but not large ones. Here we developed GRAND editing to precisely insert large DNA fragments without DNA donors. In contrast to prime editors, which require reverse transcription templates hybridizing with the target sequence, GRAND editing employs a pair of prime editing guide RNAs, with reverse transcription templates nonhomologous to the target site but complementary to each other. This strategy exhibited an efficiency of up to 63.0% of a 150-bp insertion with minor by-products and 28.4% of a 250-bp insertion. It allowed insertions up to ~1 kb, although the efficiency remains low for fragments larger than 400 bp. We confirmed efficient insertion in multiple genomic loci of several cell lines and non-dividing cells, which expands the scope of genome editing to enable donor-free insertion of large DNA sequences.


Assuntos
Edição de Genes , RNA Guia de Cinetoplastídeos , Sistemas CRISPR-Cas , DNA/genética , Genoma , Genômica , RNA Guia de Cinetoplastídeos/genética
4.
J Virol ; 98(4): e0024224, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38446633

RESUMO

Viral genomes frequently harbor overlapping genes, complicating the development of virus-vectored vaccines and gene therapies. This study introduces a novel conditional splicing system to precisely control the expression of such overlapping genes through recombinase-mediated conditional splicing. We refined site-specific recombinase (SSR) conditional splicing systems and explored their mechanisms. The systems demonstrated exceptional inducibility (116,700-fold increase) with negligible background expression, facilitating the conditional expression of overlapping genes in adenovirus-associated virus (AAV) and human immunodeficiency virus type 1. Notably, this approach enabled the establishment of stable AAV producer cell lines, encapsulating all necessary packaging genes. Our findings underscore the potential of the SSR-conditional splicing system to significantly advance vector engineering, enhancing the efficacy and scalability of viral-vector-based therapies and vaccines. IMPORTANCE: Regulating overlapping genes is vital for gene therapy and vaccine development using viral vectors. The regulation of overlapping genes presents challenges, including cytotoxicity and impacts on vector capacity and genome stability, which restrict stable packaging cell line development and broad application. To address these challenges, we present a "loxp-splice-loxp"-based conditional splicing system, offering a novel solution for conditional expression of overlapping genes and stable cell line establishment. This system may also regulate other cytotoxic genes, representing a significant advancement in cell engineering and gene therapy as well as biomass production.


Assuntos
Dependovirus , Homologia de Genes , Genes Virais , Engenharia Genética , HIV-1 , Splicing de RNA , Humanos , Linhagem Celular , Dependovirus/genética , DNA Nucleotidiltransferases/genética , DNA Nucleotidiltransferases/metabolismo , Regulação Viral da Expressão Gênica , Homologia de Genes/genética , Genes Virais/genética , Engenharia Genética/métodos , Terapia Genética/métodos , Vetores Genéticos/genética , HIV-1/genética , Splicing de RNA/genética , Vacinas/biossíntese , Vacinas/genética , Empacotamento do Genoma Viral/genética
5.
BMC Bioinformatics ; 25(1): 77, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378489

RESUMO

BACKGROUND: Cryo-electron microscopy (Cryo-EM) plays an increasingly important role in the determination of the three-dimensional (3D) structure of macromolecules. In order to achieve 3D reconstruction results close to atomic resolution, 2D single-particle image classification is not only conducive to single-particle selection, but also a key step that affects 3D reconstruction. The main task is to cluster and align 2D single-grain images into non-heterogeneous groups to obtain sharper single-grain images by averaging calculations. The main difficulties are that the cryo-EM single-particle image has a low signal-to-noise ratio (SNR), cannot manually label the data, and the projection direction is random and the distribution is unknown. Therefore, in the low SNR scenario, how to obtain the characteristic information of the effective particles, improve the clustering accuracy, and thus improve the reconstruction accuracy, is a key problem in the 2D image analysis of single particles of cryo-EM. RESULTS: Aiming at the above problems, we propose a learnable deep clustering method and a fast alignment weighted averaging method based on frequency domain space to effectively improve the class averaging results and improve the reconstruction accuracy. In particular, it is very prominent in the feature extraction and dimensionality reduction module. Compared with the classification method based on Bayesian and great likelihood, a large amount of single particle data is required to estimate the relative angle orientation of macromolecular single particles in the 3D structure, and we propose that the clustering method shows good results. CONCLUSIONS: SimcryoCluster can use the contrastive learning method to perform well in the unlabeled high-noise cryo-EM single particle image classification task, making it an important tool for cryo-EM protein structure determination.


Assuntos
Processamento de Imagem Assistida por Computador , Semântica , Microscopia Crioeletrônica/métodos , Teorema de Bayes , Processamento de Imagem Assistida por Computador/métodos , Análise por Conglomerados , Substâncias Macromoleculares
6.
J Virol ; 97(5): e0027023, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37042759

RESUMO

Understanding the facilitator of HIV-1 infection and subsequent latency establishment may aid the discovery of potential therapeutic targets. Here, we report the elevation of plasma transforming growth factor ß (TGF-ß) during acute HIV-1 infection among men who have sex with men (MSM). Using a serum-free in vitro system, we further delineated the role of TGF-ß signaling in mediating HIV-1 infection of activated and resting memory CD4+ T cells. TGF-ß could upregulate both the frequency and expression of the HIV-1 coreceptor CCR5, thereby augmenting CCR5-tropic viral infection of resting and activated memory CD4+ T cells via Smad3 activation. The production of live HIV-1JR-FL upon infection and reactivation was increased in TGF-ß-treated resting memory CD4+ T cells without increasing CD4 expression or inducing T cell activation. The expression of CCR7, a central memory T cell marker that serves as a chemokine receptor to facilitate T cell trafficking into lymphoid organs, was also elevated on TGF-ß-treated resting and activated memory CD4+ T cells. Moreover, the expression of CXCR3, a chemokine receptor recently reported to facilitate CCR5-tropic HIV-1 infection, was increased on resting and activated memory CD4+ T cells upon TGF-ß treatment. These findings were coherent with the observation that ex vivo CCR5 and CXCR3 expression on total resting and resting memory CD4+ T cells in combination antiretroviral therapy (cART)-naive and cART-treated patients were higher than in healthy individuals. Overall, the study demonstrated that TGF-ß upregulation induced by acute HIV-1 infection might promote latency reservoir establishment by increasing infected resting memory CD4+ T cells and lymphoid organ homing of infected central memory CD4+ T cells. Therefore, TGF-ß blockade may serve as a potential supplementary regimen for HIV-1 functional cure by reducing viral latency. IMPORTANCE Incomplete eradication of HIV-1 latency reservoirs remains the major hurdle in achieving a complete HIV/AIDS cure. Dissecting the facilitator of latency reservoir establishment may aid the discovery of druggable targets for HIV-1 cure. This study showed that the T cell immunomodulatory cytokine TGF-ß was upregulated during the acute phase of infection. Using an in vitro serum-free system, we specifically delineated that TGF-ß promoted HIV-1 infection of both resting and activated memory CD4+ T cells via the induction of host CCR5 coreceptor. Moreover, TGF-ß-upregulated CCR7 or CXCR3 might promote HIV-1 latent infection by facilitating lymphoid homing or IP-10-mediated viral entry and DNA integration, respectively. Infected resting and central memory CD4+ T cells are important latency reservoirs. Increased infection of these cells mediated by TGF-ß will promote latency reservoir establishment during early infection. This study, therefore, highlighted the potential use of TGF-ß blockade as a supplementary regimen with cART in acute patients to reduce viral latency.


Assuntos
Linfócitos T CD4-Positivos , Infecções por HIV , HIV-1 , Homossexualidade Masculina , Transdução de Sinais , Humanos , Masculino , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/tratamento farmacológico , Soropositividade para HIV , HIV-1/fisiologia , Receptores CCR7/metabolismo , Minorias Sexuais e de Gênero , Fator de Crescimento Transformador beta , Latência Viral/efeitos dos fármacos , Replicação Viral , Transdução de Sinais/efeitos dos fármacos
7.
Surg Endosc ; 38(2): 648-658, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38012440

RESUMO

BACKGROUND: Portal vein system thrombosis (PVST) is a potentially fatal complication after splenectomy with esophagogastric devascularization (SED) in cirrhotic patients with portal hypertension. However, the impact of portal vein velocity (PVV) on PVST after SED remains unclear. Therefore, this study aims to explore this issue. METHODS: Consecutive cirrhotic patients with portal hypertension who underwent SED at Tongji Hospital between January 2010 and June 2022 were enrolled. The patients were divided into two groups based on the presence or absence of PVST, which was assessed using ultrasound or computed tomography after the operation. PVV was measured by duplex Doppler ultrasound within one week before surgery. The independent risk factors for PVST were analyzed using univariate and multivariate logistic regression analysis. A nomogram based on these variables was developed and internally validated using 1000 bootstrap resamples. RESULTS: A total of 562 cirrhotic patients with portal hypertension who underwent SED were included, and PVST occurred in 185 patients (32.9%). Multivariate logistic regression analysis showed that PVV was the strongest independent risk factor for PVST. The incidence of PVST was significantly higher in patients with PVV ≤ 16.5 cm/s than in those with PVV > 16.5 cm/s (76.2% vs. 8.5%, p < 0.0001). The PVV-based nomogram was internally validated and showed good performance (optimism-corrected c-statistic = 0.907). Decision curve and clinical impact curve analyses indicated that the nomogram provided a high clinical benefit. CONCLUSION: A nomogram based on PVV provided an excellent preoperative prediction of PVST after splenectomy with esophagogastric devascularization.


Assuntos
Hipertensão Portal , Trombose Venosa , Humanos , Veia Porta/patologia , Esplenectomia/efeitos adversos , Cirrose Hepática/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia , Hipertensão Portal/cirurgia , Hipertensão Portal/complicações
8.
HPB (Oxford) ; 26(6): 753-763, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38485565

RESUMO

BACKGROUND: Anatomical sectionectomy based on Takasaki's segmentation has shown advantages in hepatocellular carcinoma. However, whether this approach improves the survival of intrahepatic cholangiocarcinoma (ICC) remains unknown. METHODS: A series of 248 consecutive patients with solitary ICCs who underwent hepatectomy were studied retrospectively. The patients were classified into the groups of anatomical sectionectomy based on Takasaki's segmentation (TS group) and non-Takasaki's hepatectomy (NTH group). The bias between the two groups was minimized using propensity score matching (PSM). Recurrence-free survival (RFS) and overall survival (OS) were evaluated with Kaplan-Meier analysis. The Cox proportional hazards model was performed to determine the adverse risk factors associated with survival. RESULTS: After PSM, 67 pairs of patients were compared. Both the RFS and OS rates in the TS group were significantly better than those in the NTH group (23.2 % vs. 16.5 %, and 40.4 % vs. 27.3 %, P = 0.035 and 0.032, respectively). Multivariate analysis showed that NTH was independently associated with worse RFS and OS than TS. The stratified analysis demonstrated that the RFS and OS rates in the TS group with tumor stage I and tumor size ≥3 cm were significantly better than those in the NTH group, while the survival rates for ICC with stage I and tumor size <3 cm or stage II-III showed no significant difference. CONCLUSION: TS was associated with improved RFS and OS in patients with solitary ICC even after PSM. TS may be preferred particularly in patients with tumor stage I and tumor size ≥3 cm.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Hepatectomia , Pontuação de Propensão , Humanos , Colangiocarcinoma/cirurgia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Masculino , Feminino , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/mortalidade , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estimativa de Kaplan-Meier
9.
N Engl J Med ; 382(18): 1708-1720, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32109013

RESUMO

BACKGROUND: Since December 2019, when coronavirus disease 2019 (Covid-19) emerged in Wuhan city and rapidly spread throughout China, data have been needed on the clinical characteristics of the affected patients. METHODS: We extracted data regarding 1099 patients with laboratory-confirmed Covid-19 from 552 hospitals in 30 provinces, autonomous regions, and municipalities in mainland China through January 29, 2020. The primary composite end point was admission to an intensive care unit (ICU), the use of mechanical ventilation, or death. RESULTS: The median age of the patients was 47 years; 41.9% of the patients were female. The primary composite end point occurred in 67 patients (6.1%), including 5.0% who were admitted to the ICU, 2.3% who underwent invasive mechanical ventilation, and 1.4% who died. Only 1.9% of the patients had a history of direct contact with wildlife. Among nonresidents of Wuhan, 72.3% had contact with residents of Wuhan, including 31.3% who had visited the city. The most common symptoms were fever (43.8% on admission and 88.7% during hospitalization) and cough (67.8%). Diarrhea was uncommon (3.8%). The median incubation period was 4 days (interquartile range, 2 to 7). On admission, ground-glass opacity was the most common radiologic finding on chest computed tomography (CT) (56.4%). No radiographic or CT abnormality was found in 157 of 877 patients (17.9%) with nonsevere disease and in 5 of 173 patients (2.9%) with severe disease. Lymphocytopenia was present in 83.2% of the patients on admission. CONCLUSIONS: During the first 2 months of the current outbreak, Covid-19 spread rapidly throughout China and caused varying degrees of illness. Patients often presented without fever, and many did not have abnormal radiologic findings. (Funded by the National Health Commission of China and others.).


Assuntos
Betacoronavirus , Infecções por Coronavirus , Surtos de Doenças , Pandemias , Pneumonia Viral , Adolescente , Adulto , Idoso , COVID-19 , Criança , China/epidemiologia , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/terapia , Feminino , Febre/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Pneumonia Viral/complicações , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/terapia , SARS-CoV-2 , Adulto Jovem
10.
J Virol ; 96(7): e0216121, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35297660

RESUMO

Vaccine-induced protective T cell immunity is necessary for HIV-1 functional cure. We previously reported that rhesus PD1-Gag-based DNA vaccination sustained simian-human immunodeficiency virus (SHIV) suppression by inducing effector-memory CD8+ T cells. Here, we investigated a human PD1-Gag-based DNA vaccine, namely, ICVAX, for clinical translation. PD1-based dendritic cell targeting and mosaic antigenic designs were combined to generate the ICVAX by fusing the human soluble PD1 domain with a bivalent HIV-1 Gag-p41 mosaic antigen. The mosaic antigen was cross-reactive with patients infected with B, CRF07/08_BC, and CRF01_AE variants. In mice, ICVAX elicited stronger, broader, and more polyfunctional T cell responses than mosaic Gag-p41 alone, and suppressed EcoHIV infection more efficiently. In macaques, ICVAX elicited polyfunctional effector-memory T cell responses that targeted multiple nonoverlapping epitopes of the Gag-p41 antigen. Furthermore, ICVAX manufactured following good manufacturing practices proved potent immunogenicity in macaques after biannual homologous vaccination, warranting clinical evaluation of ICVAX as an immunotherapy against HIV-1. IMPORTANCE This study presents that ICVAX, a PD1-based DNA vaccine against HIV-1, could induce broad and polyfunctional T cell responses against different HIV-1 subtypes. ICVAX encodes a recombinant antigen consisting of the human soluble PD1 domain fused with two mosaic Gag-p41 antigens. The mosaic antigens cover more than 500 HIV-1 strains circulating in China including the subtypes B/B', CRF01_AE, and CRF07/08_BC. In mice, ICVAX elicited stronger, broader, and more polyfunctional T cell responses, with better EcoHIV suppression than the nontargeting mosaic Gag-p41 DNA vaccine. Moreover, both lab-generated and GMP-grade ICVAX also elicited strong polyfunctional effector-memory T cell responses in rhesus macaques with good immunogenicity against multiple nonoverlapping epitopes of the Gag-p41 antigen. This study therefore highlights the great potential to translate the PD1-based DNA vaccine approach into clinical use, and opens up new avenues for alternative HIV-1 vaccine design for HIV-1 preventive and functional cure.


Assuntos
Infecções por HIV , HIV-1 , Vacinas Combinadas , Vacinas de DNA , Vacinas Virais , Vacinas contra a AIDS/imunologia , Animais , Antígenos Virais , Antígeno CD48 , Linfócitos T CD8-Positivos , Epitopos/imunologia , Produtos do Gene gag/genética , Produtos do Gene gag/imunologia , Infecções por HIV/prevenção & controle , HIV-1/genética , Humanos , Macaca mulatta , Células T de Memória , Camundongos , Vacinas Combinadas/genética , Vacinas Combinadas/imunologia , Vacinas de DNA/genética , Vacinas de DNA/imunologia , Vacinas Virais/genética , Vacinas Virais/imunologia
11.
J Nanobiotechnology ; 21(1): 96, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36935493

RESUMO

The incidence and mortality rates of lung cancer are among the highest in the world. Traditional treatment methods include surgery, chemotherapy, and radiotherapy. Although rapid progress has been achieved in the past decade, treatment limitations remain. It is therefore imperative to identify safer and more effective therapeutic methods, and research is currently being conducted to identify more efficient and less harmful drugs. In recent years, the discovery of antitumor drugs based on the essential trace element selenium (Se) has provided good prospects for lung cancer treatments. In particular, compared to inorganic Se (Inorg-Se) and organic Se (Org-Se), Se nanomedicine (Se nanoparticles; SeNPs) shows much higher bioavailability and antioxidant activity and lower toxicity. SeNPs can also be used as a drug delivery carrier to better regulate protein and DNA biosynthesis and protein kinase C activity, thus playing a role in inhibiting cancer cell proliferation. SeNPs can also effectively activate antigen-presenting cells to stimulate cell immunity, exert regulatory effects on innate and regulatory immunity, and enhance lung cancer immunotherapy. This review summarizes the application of Se-based species and materials in lung cancer diagnosis, including fluorescence, MR, CT, photoacoustic imaging and other diagnostic methods, as well as treatments, including direct killing, radiosensitization, chemotherapeutic sensitization, photothermodynamics, and enhanced immunotherapy. In addition, the application prospects and challenges of Se-based drugs in lung cancer are examined, as well as their forecasted future clinical applications and sustainable development.


Assuntos
Neoplasias Pulmonares , Nanopartículas , Selênio , Humanos , Selênio/uso terapêutico , Selênio/metabolismo , Medicina de Precisão , Nanomedicina , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Antioxidantes/metabolismo , Nanopartículas/uso terapêutico , Portadores de Fármacos
12.
BMC Public Health ; 23(1): 1223, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37353781

RESUMO

BACKGROUND: Health literacy (HL) is associated with health outcomes, but little is known about the occupational HL (OHL) for port employees and its link to the length of service and job category. METHOD: A cross-sectional survey was conducted on 3492 port employees from the Occupational Health Survey for Port Employees project, and a special questionnaire was utilized to measure the OHL status. Binary and ordinal logistic regressions were used to estimate the association. RESULT: Among the participants, 72.90% had sufficient OHL with a mean score (standard deviation) of 53.10 (7.26). Binary logistic regression results indicated that the association between length of service (33-40 years group Adjusted OR = 1.11; 41-49 years group Adjusted OR = 1.14; ≥50 years group Adjusted OR = 1.19) and job category (longshoremen Adjusted OR = 0.90; driver Adjusted OR = 0.91) with OHL were statistically significant. Ordinal logistic regression results indicated that, for OHL, Adjusted OR was increased in different lengths of service level (33-40 years group, Adjusted OR = 1.50; 41-49 years group, Adjusted OR = 1.75; ≥50 years group, Adjusted OR = 2.19), and the Adjusted OR of skilled workers was 1.60. CONCLUSION: Most port participants had sufficient OHL, and the length of service and job category could affect OHL. The effect of the length of service may be more obvious; the length of service can promote the improvement of OHL continuously.


Assuntos
Letramento em Saúde , Saúde Ocupacional , Humanos , Saúde Bucal , Estudos Transversais , China
13.
Eur J Immunol ; 51(9): 2296-2305, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34089541

RESUMO

The increasing numbers of infected cases of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses serious threats to public health and the global economy. Most SARS-CoV-2 neutralizing antibodies target the receptor binding domain (RBD) and some the N-terminal domain (NTD) of the spike protein, which is the major antigen of SARS-CoV-2. While the antibody response to RBD has been extensively characterized, the antigenicity and immunogenicity of the NTD protein are less well studied. Using 227 plasma samples from COVID-19 patients, we showed that SARS-CoV-2 NTD-specific antibodies could be induced during infection. As compared to the results of SARS-CoV-2 RBD, the serological response of SARS-CoV-2 NTD is less cross-reactive with SARS-CoV, a pandemic strain that was identified in 2003. Furthermore, neutralizing antibodies are rarely elicited in a mice model when NTD is used as an immunogen. We subsequently demonstrate that NTD has an altered antigenicity when expressed alone. Overall, our results suggest that while NTD offers a supplementary strategy for serology testing, it may not be suitable as an immunogen for vaccine development.


Assuntos
COVID-19/imunologia , Domínios Proteicos/imunologia , SARS-CoV-2/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linhagem Celular , Chlorocebus aethiops , Reações Cruzadas/imunologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Pandemias/prevenção & controle , Ligação Proteica/imunologia , Células Sf9 , Células Vero
14.
J Virol ; 95(12)2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-33789991

RESUMO

Recombinant influenza A viral (IAV) vectors are potential to stimulate systemic and mucosal immunity, but the packaging capacity is limited and only one or a few epitopes can be carried. Here, we report the generation of a replication-competent IAV vector that carries a full-length HIV-1 p24 gene linked to the 5'-terminal coding region of the neuraminidase segment via a protease cleavage sequence (IAV-p24). IAV-p24 was successfully rescued and stably propagated, and P24 protein was efficiently expressed in infected mammalian cells. In BALB/c mice, IAV-p24 showed attenuated pathogenicity compared to that of the parental A/PR/8/34 (H1N1) virus. An intranasal inoculation with IAV-p24 elicited moderate HIV-specific cell-mediated immune (CMI) responses in the airway and vaginal tracts and in the spleen, and an intranasal boost with a replication-incompetent adenovirus type 2 vector expressing the HIV-1 gag gene (Ad2-gag) greatly improved these responses. Importantly, compared to an Ad2-gag prime plus IAV-p24 boost regimen, the IAV-p24 prime plus Ad2-gag boost regimen had a greater efficacy in eliciting HIV-specific CMI responses. P24-specific CD8+ T cells and antibodies were robustly provoked both systemically and in mucosal sites and showed long-term durability, revealing that IAV-p24 may be used as a mucosa-targeted priming vaccine. Our results illustrate that IAV-p24 is able to prime systemic and mucosal immunity against HIV-1 and warrants further evaluation in nonhuman primates.IMPORTANCE An effective HIV-1 vaccine remains elusive despite nearly 40 years of research. CD8+ T cells and protective antibodies may both be desirable for preventing HIV-1 infection in susceptible mucosal sites. Recombinant influenza A virus (IAV) vector has the potential to stimulate these immune responses, but the packaging capacity is extremely limited. Here, we describe a replication-competent IAV vector expressing the HIV-1 p24 gene (IAV-p24). Unlike most other IAV vectors that carried one or several antigenic epitopes, IAV-p24 stably expressed the full-length P24 protein, which contains multiple epitopes and is highly conserved among all known HIV-1 sequences. Compared to the parental A/PR/8/34 (H1N1) virus, IAV-p24 showed an attenuated pathogenicity in BALB/c mice. When combined with an adenovirus vector expressing the HIV-1 gag gene, IAV-p24 was able to prime P24-specific systemic and mucosal immune responses. IAV-p24 as an alternative priming vaccine against HIV-1 warrants further evaluation in nonhuman primates.


Assuntos
Vacinas contra a AIDS/imunologia , Linfócitos T CD8-Positivos/imunologia , Anticorpos Anti-HIV/análise , Proteína do Núcleo p24 do HIV/imunologia , HIV-1/imunologia , Imunidade nas Mucosas , Adenoviridae/genética , Animais , Anticorpos Antivirais/sangue , Líquido da Lavagem Broncoalveolar/imunologia , Feminino , Genes gag , Anticorpos Anti-HIV/sangue , Proteína do Núcleo p24 do HIV/genética , Infecções por HIV/prevenção & controle , Imunidade Celular , Imunização Secundária , Imunogenicidade da Vacina , Imunoglobulina A/análise , Imunoglobulina A/sangue , Imunoglobulina G/análise , Imunoglobulina G/sangue , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/patogenicidade , Vírus da Influenza A Subtipo H3N2/imunologia , Tecido Linfoide/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Vacinação , Vacinas Sintéticas/imunologia
15.
Cell Mol Biol (Noisy-le-grand) ; 68(7): 135-140, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-36495505

RESUMO

In recent years, it has been found that miRNA has a very close relationship with cardiovascular system diseases. Heart disease is accompanied by a change of the miRNA expression spectrum. Changing the expression of miRNA in or out of cells can cause heart diseases such as myocardial infarction, hypertrophy or arrhythmia. Mitogen-activated protein kinases (MAPKs) are important transmitters of cell surface signals to the nucleus. The family influences the biological responses of cells (e.g., proliferation, differentiation, transformation and apoptosis) by affecting the transcription and regulation of genes in animal cells. Based on the above background, the purpose of this study was to study the effect of the mir-1-mediated AMPK pathway on cardiomyocyte apoptosis in hypertensive rats. The expression level of miRNA-1 in cultured rat H9c2 cardiomyocytes was detected by real-time PCR to determine the success of the transfection. MTT method was used to detect the cell viability. Flow cytometry was used to detect the cell apoptosis, and real-time PCR and Western blot were used to detect the mRNA and protein expression of bcl-2. The results were compared with those of H9c2 cells (blank control group) and miRNA negative control fragments (negative control group). As an important kinase regulating energy homeostasis, AMPK is one of the central regulators of metabolism in eukaryotic cells and organisms, responsible for regulating cellular capacity input and output and maintaining the smooth functioning of cellular physiological activities. At the same time, AMPK is a key protein involved in a variety of signaling pathways. The results showed that the apoptosis rate of myocardial cells in the miRNA-1 group decreased (0.710 ± 0.009661)% vs (1.066667 ± 0.02603)% compared with that in the spontaneous hypertension control group (P < 0.001). The transfected miRNA-1mimics can up-regulate the expression of miRNA-1 in cells, inhibit the proliferation of cardiomyocytes and promote apoptosis.


Assuntos
Hipertensão , MicroRNAs , Ratos , Animais , Apoptose/genética , Miócitos Cardíacos/metabolismo , MicroRNAs/metabolismo , Transdução de Sinais , Hipertensão/genética , Hipertensão/metabolismo
16.
Sensors (Basel) ; 22(17)2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-36080933

RESUMO

The required navigation performance (RNP) procedure is one of the two basic navigation specifications for the performance-based navigation (PBN) procedure as proposed by the International Civil Aviation Organization (ICAO) through an integration of the global navigation infrastructures to improve the utilization efficiency of airspace and reduce flight delays and the dependence on ground navigation facilities. The approach stage is one of the most important and difficult stages in the whole flying. In this study, we proposed deep reinforcement learning (DRL)-based RNP procedure execution, DRL-RNP. By conducting an RNP approach procedure, the DRL algorithm was implemented, using a fixed-wing aircraft to explore a path of minimum fuel consumption with reward under windy conditions in compliance with the RNP safety specifications. The experimental results have demonstrated that the six degrees of freedom aircraft controlled by the DRL algorithm can successfully complete the RNP procedure whilst meeting the safety specifications for protection areas and obstruction clearance altitude in the whole procedure. In addition, the potential path with minimum fuel consumption can be explored effectively. Hence, the DRL method can be used not only to implement the RNP procedure with a simulated aircraft but also to help the verification and evaluation of the RNP procedure.


Assuntos
Aviação , Aeronaves , Algoritmos , Recompensa
17.
Brief Bioinform ; 20(1): 102-109, 2019 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-28968662

RESUMO

Adenosine-to-inosine (A-to-I) editing by adenosine deaminase acting on the RNA (ADAR) proteins is one of the most frequent modifications during post- and co-transcription. To facilitate the assignment of biological functions to specific editing sites, we designed an automatic online platform to annotate A-to-I RNA editing sites in pre-mRNA splicing signals, microRNAs (miRNAs) and miRNA target untranslated regions (3' UTRs) from human (Homo sapiens) high-throughput sequencing data and predict their effects based on large-scale bioinformatic analysis. After analysing plenty of previously reported RNA editing events and human normal tissues RNA high-seq data, >60 000 potentially effective RNA editing events on functional genes were found. The RNA Editing Plus platform is available for free at https://www.rnaeditplus.org/, and we believe our platform governing multiple optimized methods will improve further studies of A-to-I-induced editing post-transcriptional regulation.


Assuntos
Adenosina Desaminase/metabolismo , Edição de RNA , Proteínas de Ligação a RNA/metabolismo , Software , Regiões 3' não Traduzidas , Adenosina/genética , Adenosina/metabolismo , Processamento Alternativo/genética , Sequência de Bases , Biologia Computacional , Bases de Dados de Ácidos Nucleicos/estatística & dados numéricos , Feminino , Ontologia Genética , Humanos , Inosina/genética , Inosina/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Mutação de Sentido Incorreto , Edição de RNA/genética , Precursores de RNA/genética , Precursores de RNA/metabolismo , Análise de Sequência de RNA/estatística & dados numéricos , Máquina de Vetores de Suporte , Distribuição Tecidual
18.
J Org Chem ; 86(24): 18056-18066, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34842425

RESUMO

We report here a direct allenylation reaction of inactive cyclic ethers. The reaction proceeds through a copper-catalyzed 1,4-difunctionalization of 1,3-enynes, with cyano group installed at the allenes simultaneously. This methodology shows a broad functional group compatibility to 1,3-enynes. Diversified allene-modified cyclic ether derivatives were synthesized with high regioselectivity under mild conditions.

19.
BMC Pulm Med ; 21(1): 402, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34872535

RESUMO

BACKGROUND: Eosinophilic pleural effusion (EPE) is a distinct entity among pleural effusions, but its diagnostic and prognostic significance is still controversial. This study aimed to evaluate the incidence and aetiological distribution of EPE in our institution and to assess the relationship between EPE and malignancy and other underlying diseases and the relevance of the percentage of eosinophils and other laboratory parameters. METHODS: A retrospective study was conducted by reviewing the medical records of 252 patients with PE from September 2017 to January 2021. RESULTS: EPE was found in 34 (13.49%) out of 252 patients. There were 20 (58.82%) males and 14 (41.18%) females in the EPE group. The mean percentage of eosinophils in EPE (21.7%, range (10.0-67.5%)) was significantly higher than the percentage of eosinophils in peripheral blood (5.65%, range (0-34.60%); p < 0.05). The most common cause of EPE was malignant disease (52.94%), followed by idiopathy (14.71%), parasites (8.82%), pneumonia (8.82%) and others (14.71%). Comparative analysis of patients with malignant versus nonmalignant EPE showed that patients with malignant EPE were significantly older, and had a lower white blood cell (WBC) count in the pleural fluid (1.8 vs 4.7 cells × 109/L, p < 0.05). However, the percentage of eosinophils in PE was not significantly different between malignant EPE and nonmalignant EPE (p = 0.66). There was no correlation between the percentage of eosinophils in PE and peripheral blood (r = 0.29; p = 0.09). CONCLUSIONS: Malignant disease ranks as the leading cause of EPE. The presence of EPE should not be considered as a predictive factor of benign conditions. Pleural parasitic infestation (PPI) should be emphasized in areas with a high incidence of parasitic disease.


Assuntos
Eosinofilia/sangue , Eosinofilia/epidemiologia , Derrame Pleural/sangue , Derrame Pleural/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Comorbidade , Eosinofilia/patologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Derrame Pleural/patologia , Estudos Retrospectivos
20.
J Sci Food Agric ; 101(7): 2912-2919, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33155672

RESUMO

BACKGROUND: Gelatin is traditionally produced from mammals and widely applied in the food industry. The production is tedious, time-consuming and environment-unfriendly, while the application is restricted because of zoonosis risk and religious sentiment. RESULTS: Gelatin was extracted by hot water from sturgeon swim bladder after defatting with alcohol and hexane. The yield reached to 94.15% under the optimized conditions of 50 °C, 30 min and 10 mL g-1 . Its amino acid and subunit profiles were similar to type I collagen. Compared to commercial porcine, bovine and piscine gelatins, it exhibited higher whiteness (3.38), emulsion activity (171.76 m2 g-1 ), gel strength (853.23 g), water-holding capacity (92.37%) and viscoelasticity (0.03). But the transmittance (40.56% at 450 nm and 59.07% at 620 nm), emulsion stability (30.09 min), foam expansion (203.00) and stability (26.92), gelling (16.88 °C) and melting temperature (21.80 °C) were lower. While the pH (6.87) and viscosity (28.60 mPa s) were moderate. Moreover, it made better hydrogels and nanofibers. CONCLUSION: Gelatin was extracted from sturgeon swim bladder using a clean and efficient approach, and exhibited unique properties and great potential for the food industry. © 2020 Society of Chemical Industry.


Assuntos
Sacos Aéreos/química , Fracionamento Químico/métodos , Proteínas de Peixes/química , Gelatina/química , Aminoácidos/análise , Animais , Bovinos , Colágeno Tipo I/análise , Proteínas de Peixes/isolamento & purificação , Peixes , Gelatina/isolamento & purificação , Géis/química , Géis/isolamento & purificação , Suínos , Viscosidade
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