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1.
Opt Lett ; 49(11): 2914-2917, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824291

RESUMO

Traditional absorption spectroscopy has a fundamental difficulty in resolving small absorbance from a strong background due to the instability of laser sources. Existing background-free methods in broadband vibrational spectroscopy help to alleviate this problem but face challenges in realizing either low extinction ratios or time-resolved field measurements. Here, we introduce optical-parametric-amplification-enhanced background-free spectroscopy, in which the excitation background is first suppressed by an interferometer, and then the free-induction decay that carries molecular signatures is selectively amplified. We show that this method can improve the limit of detection in linear interferometry by order(s) of magnitude without requiring lower extinction ratios or a time-resolved measurement, which can benefit sensing applications in detecting trace species.

2.
Front Cell Infect Microbiol ; 14: 1388059, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38846352

RESUMO

Introduction: HIV molecular network based on genetic distance (GD) has been extensively utilized. However, the GD threshold for the non-B subtype differs from that of subtype B. This study aimed to optimize the GD threshold for inferring the CRF01_AE molecular network. Methods: Next-generation sequencing data of partial CRF01_AE pol sequences were obtained for 59 samples from 12 transmission pairs enrolled from a high-risk cohort during 2009 and 2014. The paired GD was calculated using the Tamura-Nei 93 model to infer a GD threshold range for HIV molecular networks. Results: 2,019 CRF01_AE pol sequences and information on recent HIV infection (RHI) from newly diagnosed individuals in Shenyang from 2016 to 2019 were collected to construct molecular networks to assess the ability of the inferred GD thresholds to predict recent transmission events. When HIV transmission occurs within a span of 1-4 years, the mean paired GD between the sequences of the donor and recipient within the same transmission pair were as follow: 0.008, 0.011, 0.013, and 0.023 substitutions/site. Using these four GD thresholds, it was found that 98.9%, 96.0%, 88.2%, and 40.4% of all randomly paired GD values from 12 transmission pairs were correctly identified as originating from the same transmission pairs. In the real world, as the GD threshold increased from 0.001 to 0.02 substitutions/site, the proportion of RHI within the molecular network gradually increased from 16.6% to 92.3%. Meanwhile, the proportion of links with RHI gradually decreased from 87.0% to 48.2%. The two curves intersected at a GD of 0.008 substitutions/site. Discussion: A suitable range of GD thresholds, 0.008-0.013 substitutions/site, was identified to infer the CRF01_AE molecular transmission network and identify HIV transmission events that occurred within the past three years. This finding provides valuable data for selecting an appropriate GD thresholds in constructing molecular networks for non-B subtypes.


Assuntos
Infecções por HIV , HIV-1 , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/genética , HIV-1/classificação , Genótipo , Filogenia , Masculino , Feminino , China , Variação Genética , Adulto
3.
Viruses ; 16(4)2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38675896

RESUMO

Neutralizing antibodies (NtAbs) against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are indicators of vaccine efficacy that enable immunity surveillance. However, the rapid mutation of SARS-CoV-2 variants prevents the timely establishment of standards required for effective XBB vaccine evaluation. Therefore, we prepared four candidate standards (No. 11, No. 44, No. 22, and No. 33) using plasma, purified immunoglobulin, and a broad-spectrum neutralizing monoclonal antibody. Collaborative calibration was conducted across nine Chinese laboratories using neutralization methods against 11 strains containing the XBB and BA.2.86 sublineages. This study demonstrated the reduced neutralization potency of the first International Standard antibodies to SARS-CoV-2 variants of concern against XBB variants. No. 44 displayed broad-spectrum neutralizing activity against XBB sublineages, effectively reduced interlaboratory variability for nearly all XBB variants, and effectively minimized the geometric mean titer (GMT) difference between the live and pseudotyped virus. No. 22 showed a broader spectrum and higher neutralizing activity against all strains but failed to reduce interlaboratory variability. Thus, No. 44 was approved as a National Standard for NtAbs against XBB variants, providing a unified NtAb measurement standard for XBB variants for the first time. Moreover, No. 22 was approved as a national reference reagent for NtAbs against SARS-CoV-2, offering a broad-spectrum activity reference for current and potentially emerging variants.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , Testes de Neutralização , SARS-CoV-2 , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Humanos , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , COVID-19/imunologia , COVID-19/virologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/genética , Vacinas contra COVID-19/imunologia , China , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética
4.
Mol Oncol ; 18(5): 1327-1346, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38383842

RESUMO

SRY-box transcription factor 6 (SOX6) is a member of the SOX gene family and inhibits the proliferation of cervical cancer cells by inducing cell cycle arrest. However, the final cell fate and significance of these cell-cycle-arrested cervical cancer cells induced by SOX6 remains unclear. Here, we report that SOX6 inhibits the proliferation of cervical cancer cells by inducing cellular senescence, which is mainly mediated by promoting transforming growth factor beta 2 (TGFB2) gene expression and subsequently activating the TGFß2-Smad2/3-p53-p21WAF1/CIP1-Rb pathway. SOX6 promotes TGFB2 gene expression through the MAP4K4-MAPK (JNK/ERK/p38)-ATF2 and WT1-ATF2 pathways, which is dependent on its high-mobility group (HMG) domain. In addition, the SOX6-induced senescent cervical cancer cells are resistant to cisplatin treatment. ABT-263 (navitoclax) and ABT-199 (venetoclax), two classic senolytics, can specifically eliminate the SOX6-induced senescent cervical cancer cells, and thus significantly improve the chemosensitivity of cisplatin-resistant cervical cancer cells. This study uncovers that the MAP4K4/WT1-ATF2-TGFß2 axis mediates SOX6-induced cellular senescence, which is a promising therapeutic target in improving the chemosensitivity of cervical cancer.


Assuntos
Fator 2 Ativador da Transcrição , Senescência Celular , Fatores de Transcrição SOXD , Transdução de Sinais , Proteína Smad2 , Fator de Crescimento Transformador beta2 , Neoplasias do Colo do Útero , Animais , Feminino , Humanos , Camundongos , Fator 2 Ativador da Transcrição/metabolismo , Fator 2 Ativador da Transcrição/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteína Smad2/metabolismo , Proteína Smad3 , Fatores de Transcrição SOXD/metabolismo , Fatores de Transcrição SOXD/genética , Fator de Crescimento Transformador beta2/metabolismo , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/genética
5.
Emerg Microbes Infect ; 13(1): 2322671, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38390796

RESUMO

The increasing incidence of diseases caused by Coxsackievirus A6 (CV-A6) and the presence of various mutants in the population present significant public health challenges. Given the concurrent development of multiple vaccines in China, it is challenging to objectively and accurately evaluate the level of neutralizing antibody response to different vaccines. The choice of the detection strain is a crucial factor that influences the detection of neutralizing antibodies. In this study, the National Institutes for Food and Drug Control collected a prototype strain (Gdula), one subgenotype D1, as well as 13 CV-A6 candidate vaccine strains and candidate detection strains (subgenotype D3) from various institutions and manufacturers involved in research and development. We evaluated cross-neutralization activity using plasma from naturally infected adults (n = 30) and serum from rats immunized with the aforementioned CV-A6 strains. Although there were differences between the geometric mean titer (GMT) ranges of human plasma and murine sera, the overall trends were similar. A significant effect of each strain on the neutralizing antibody test (MAX/MIN 48.0 ∼16410.3) was observed. Among all strains, neutralization of the S112 strain by 15 different sera resulted in higher neutralizing antibody titers (GMTS112 = 132.0) and more consistent responses across different genotypic immune sera (MAX/MIN = 48.0). Therefore, S112 may serve as a detection strain for NtAb testing in various vaccines, minimizing bias and making it suitable for evaluating the immunogenicity of the CV-A6 vaccine.


Assuntos
Anticorpos Neutralizantes , Vacinas , Adulto , Humanos , Animais , Camundongos , Ratos , Anticorpos Antivirais , Pesquisa , China
6.
Science ; 382(6671): 708-713, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37943937

RESUMO

Mode-locked lasers (MLLs) generate ultrashort pulses with peak powers substantially exceeding their average powers. However, integrated MLLs that drive ultrafast nanophotonic circuits have remained elusive because of their typically low peak powers, lack of controllability, and challenges when integrating with nanophotonic platforms. In this work, we demonstrate an electrically pumped actively MLL in nanophotonic lithium niobate based on its hybrid integration with a III-V semiconductor optical amplifier. Our MLL generates [Formula: see text]4.8-ps optical pulses around 1065 nm at a repetition rate of ∼10 GHz, with energies exceeding 2.6 pJ and peak powers beyond 0.5 W. The repetition rate and the carrier-envelope offset frequency of the output can be controlled in a wide range by using the driving frequency and the pump current, providing a route for fully stabilized on-chip frequency combs.

7.
Nat Commun ; 14(1): 6549, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848411

RESUMO

Optical frequency comb is an enabling technology for a multitude of applications from metrology to ranging and communications. The tremendous progress in sources of optical frequency combs has mostly been centered around the near-infrared spectral region, while many applications demand sources in the visible and mid-infrared, which have so far been challenging to achieve, especially in nanophotonics. Here, we report widely tunable frequency comb generation using optical parametric oscillators in lithium niobate nanophotonics. We demonstrate sub-picosecond frequency combs tunable beyond an octave extending from 1.5 up to 3.3 µm with femtojoule-level thresholds on a single chip. We utilize the up-conversion of the infrared combs to generate visible frequency combs reaching 620 nm on the same chip. The ultra-broadband tunability and visible-to-mid-infrared spectral coverage of our source highlight a practical and universal path for the realization of efficient frequency comb sources in nanophotonics, overcoming their spectral sparsity.

8.
Signal Transduct Target Ther ; 8(1): 366, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37743418

RESUMO

With the continuous in-depth study of the interaction mechanism between viruses and hosts, the virus has become a promising tool in cancer treatment. In fact, many oncolytic viruses with selectivity and effectiveness have been used in cancer therapy. Human enterovirus is one of the most convenient sources to generate oncolytic viruses, however, the high seroprevalence of some enteroviruses limits its application which urges to exploit more oncolytic enteroviruses. In this study, coxsackievirus B5/Faulkner (CV-B5/F) was screened for its potential oncolytic effect against non-small cell lung cancers (NSCLCs) through inducing apoptosis and autophagy. For refractory NSCLCs, DNA-dependent protein kinase (DNA-PK) or ataxia telangiectasia mutated protein (ATM) inhibitors can synergize with CV-B5/F to promote refractory cell death. Here, we showed that viral infection triggered endoplasmic reticulum (ER) stress-related pro-apoptosis and autophagy signals, whereas repair for double-stranded DNA breaks (DSBs) contributed to cell survival which can be antagonized by inhibitor-induced cell death, manifesting exacerbated DSBs, apoptosis, and autophagy. Mechanistically, PERK pathway was activated by the combination of CV-B5/F and inhibitor, and the irreversible ER stress-induced exacerbated cell death. Furthermore, the degradation of activated STING by ERphagy promoted viral replication. Meanwhile, no treatment-related deaths due to CV-B5/F and/or inhibitors occurred. Conclusively, our study identifies an oncolytic CV-B5/F and the synergistic effects of inhibitors of DNA-PK or ATM, which is a potential therapy for NSCLCs.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Vírus Oncolíticos , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/terapia , Estudos Soroepidemiológicos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Apoptose/genética , Vírus Oncolíticos/genética , DNA
9.
Curr Mol Med ; 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37587827

RESUMO

BACKGROUND: The purpose of this study was to investigate the role of miR-148b in liver injury in rats with traumatic hemorrhagic shock (THS) and to elucidate its potential mechanism. METHODS: The levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the serum of rats were detected by enzyme-linked immune sorbent assay (ELISA), and the injury of rat liver was analyzed by hematoxylin-eosin (H&E) staining. Apoptosis of rat hepatocytes and normal rat liver cell line (BRL3A) was identified by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay and flow cytometry, respectively. MiR-148b and sirtuin 6 (SIRT6) expression was measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot. Lactate dehydrogenase (LDH) content and cell viability were measured by commercial kits and cell counting kit-8 (CCK-8) assay, respectively. The binding sites of miR-148b and SIRT6 were predicted by the Starbase database and verified by dual luciferase reporter assay. RESULTS: MiR-148b expression in THS rats or ischemia-reperfusion (I/R)-treated cells was higher than in the control group. Overexpression of miR-148b further promoted the effects of I/R, which enhanced the levels of ALT, AST and LDH, cell apoptosis of liver tissue or BRL3A cells and decreased the expression of SITR6. Besides, miR-148b negatively correlated with SIRT6, and upregulated the expression of SIRT6 could partly reverse the effect of miR-148b. CONCLUSION: Hepatocyte injury induced by I/R was achieved by regulating miR-148b /SIRT6 axis.

11.
Front Immunol ; 14: 1107639, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36865542

RESUMO

Neutralizing antibody (NtAb) levels are key indicators in the development and evaluation of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccines. Establishing a unified and reliable WHO International Standard (IS) for NtAb is crucial for the calibration and harmonization of NtAb detection assays. National and other WHO secondary standards are key links in the transfer of IS to working standards but are often overlooked. The Chinese National Standard (NS) and WHO IS were developed by China and WHO in September and December 2020, respectively, the application of which prompted and coordinated sero-detection of vaccine and therapy globally. Currently, a second-generation Chinese NS is urgently required owing to the depletion of stocks and need for calibration to the WHO IS. The Chinese National Institutes for Food and Drug Control (NIFDC) developed two candidate NSs (samples 33 and 66-99) traced to the IS according to the WHO manual for the establishment of national secondary standards through a collaborative study of nine experienced labs. Either NS candidate can reduce the systematic error among different laboratories and the difference between the live virus neutralization (Neut) and pseudovirus neutralization (PsN) methods, ensuring the accuracy and comparability of NtAb test results among multiple labs and methods, especially for samples 66-99. At present, samples 66-99 have been approved as the second-generation NS, which is the first NS calibrated tracing to the IS with 580 (460-740) International Units (IU)/mL and 580 (520-640) IU/mL by Neut and PsN, respectively. The use of standards improves the reliability and comparability of NtAb detection, ensuring the continuity of the use of the IS unitage, which effectively promotes the development and application of SARS-CoV-2 vaccines in China.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Calibragem , Reprodutibilidade dos Testes , SARS-CoV-2 , Anticorpos Antivirais , Anticorpos Neutralizantes , China , Organização Mundial da Saúde
12.
Nat Commun ; 14(1): 1044, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36828826

RESUMO

Dual-comb spectroscopy has been proven beneficial in molecular characterization but remains challenging in the mid-infrared region due to difficulties in sources and efficient photodetection. Here we introduce cross-comb spectroscopy, in which a mid-infrared comb is upconverted via sum-frequency generation with a near-infrared comb of a shifted repetition rate and then interfered with a spectral extension of the near-infrared comb. We measure CO2 absorption around 4.25 µm with a 1-µm photodetector, exhibiting a 233-cm-1 instantaneous bandwidth, 28000 comb lines, a single-shot signal-to-noise ratio of 167 and a figure of merit of 2.4 × 106 Hz1/2. We show that cross-comb spectroscopy can have superior signal-to-noise ratio, sensitivity, dynamic range, and detection efficiency compared to other dual-comb-based methods and mitigate the limits of the excitation background and detector saturation. This approach offers an adaptable and powerful spectroscopic method outside the well-developed near-IR region and opens new avenues to high-performance frequency-comb-based sensing with wavelength flexibility.


Assuntos
Espectrofotometria Infravermelho , Razão Sinal-Ruído
13.
Expert Rev Anti Infect Ther ; 20(8): 1119-1127, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35574688

RESUMO

INTRODUCTION: Effective treatments for the ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic are limited. The virus has evolved strategies to evade the immune system or hijack immune responses to facilitate infection and escape immune surveillance. Mechanistically, SARS-CoV-2 takes advantage of TLR4 and cytokine-induced integrins to promote its entrance into the cell. Furthermore, the activation of pattern recognition receptors (PRR)-mediated signaling pathways is compromised by SARS-CoV-2 non-structural proteins (NSPs), accessory protein open reading frames (ORFs), and structural proteins upon infection, contributing to viral infection and replication. Host factors necessary for cellular protein synthesis, metabolism, and viral replication can also be inhibited by the SARS-CoV-2 proteins. Exploring specific mechanisms would optimize the therapy methods and benefit drug research and development. AREAS COVERED: We describe pathways and mechanisms by which SARS-CoV-2 evades immune system; these include the mechanisms that operate during virus entry, signaling pathways involved, and processes at RNA and protein levels. EXPERT OPINION: Increased understanding of how viruses interfere with immune responses would provide more evidence for drug development. Drugs targeting conserved viral proteins to inhibit their replication or host factors to enhance immune responses would minimize the impact of virus mutations and prepare for future coronavirus outbreaks.


Assuntos
COVID-19 , Vigilância Imunológica , SARS-CoV-2 , COVID-19/imunologia , COVID-19/virologia , Citocinas , Humanos , Pandemias , Replicação Viral
14.
Virol J ; 19(1): 86, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35596222

RESUMO

To investigate the protective efficacy and mechanism of ZF2001 (a protein subunit vaccine with conditional approval in China) to SARS-CoV-2 Delta variant-induced severe pneumonia, the lethal challenge model of K18-hACE2 transgenic mice was used in this study. An inactivated-virus vaccine at the research and development stage (abbreviated as RDINA) was compared to ZF2001. We found that ZF2001 and RDINA could provide the protective effect against Delta variant-induced severe cases, as measured by the improved survival rates, the reduced virus loads, the alleviated lung histopathology and the high neutralizing antibody geomean titers, compared to aluminum adjuvant group. To prevent and control Omicron or other variant epidemics, further improvements in vaccine design and compatibilities with the novel adjuvant are required to achieve better immunogenicity.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , COVID-19/prevenção & controle , Melfalan , Camundongos , Camundongos Transgênicos , Vacinas de Produtos Inativados , gama-Globulinas
15.
Expert Rev Vaccines ; 21(4): 471-481, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35080441

RESUMO

INTRODUCTION: Major emergent infectious diseases (MEID) pose the most serious threat to human health. The research proposes targeted response strategies for the prevention and control of potential MEID. AREAS COVERED: Based on the analysis of infectious diseases, this research analyzes pandemics that have a high probability of occurrence and aims to synthesize the past experience and lessons learned of controlling infectious diseases such as coronavirus, influenza, Ebola, etc. In addition, by integrating major infectious disease response guidelines developed by WHO, the European Union, the United States, and the United Kingdom, we intend to bring forward national vaccine R&D development strategies for emergency use. EXPERT OPINION: We advise to establish and improve existing laws, regulations, and also prevention and control systems for the emergent R&D and application of vaccines in response to potential infectious diseases. The strategies would not only help increase the various abilities in response to the research, development, evaluation, production, and supervision of emergency vaccines, but also establish surrogate endpoint of immunogenicity protection in early clinical studies to enable a rapid evaluation of the efficacy of emergency vaccines.


Assuntos
Doenças Transmissíveis , Doença pelo Vírus Ebola , Vacinas contra Influenza , Influenza Humana , Doenças Transmissíveis/epidemiologia , Doença pelo Vírus Ebola/epidemiologia , Humanos , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Pandemias , Estados Unidos/epidemiologia
16.
Viruses ; 15(1)2022 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-36680102

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) protein subunit vaccine is one of the mainstream technology platforms for the development of COVID-19 vaccines, and most R&D units use the receptor-binding domain (RBD) or spike (S) protein as the main target antigen. The complexity of vaccine design, sequence, and expression systems makes it urgent to establish common antigen assays to facilitate vaccine development. In this study, we report the development of a double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) to determine the antigen content of SARS-CoV-2 protein subunit vaccines based on the United States Pharmacopeia <1220> and ICH (international conference on harmonization) Q14 and Q2 (R2) requirements. A monoclonal antibody (mAb), 20D8, was identified as the detection antibody based on its high RBD binding activity (EC50 = 8.4 ng/mL), broad-spectrum anti-variant neutralizing activity (EC50: 2.7−9.8 ng/mL for pseudovirus and EC50: 9.6−127 ng/mL for authentic virus), good in vivo protection, and a recognized linear RBD epitope (369−379 aa). A porcine anti-RBD polyclonal antibody was selected as the coating antibody. Assay performance met the requirements of the analytical target profile with an accuracy and precision of ≥90% and adequate specificity. Within the specification range of 70−143%, the method capability index was >0.96; the misjudgment probability was <0.39%. The method successfully detected SARS-CoV-2 protein subunit vaccine antigens (RBD or S protein sequences in Alpha, Beta, Gamma, or Delta variants) obtained from five different manufacturers. Thus, we present a new robust, reliable, and general method for measuring the antigenic content of SARS-CoV-2 protein subunit vaccines. In addition to currently marketed and emergency vaccines, it is suitable for vaccines in development containing antigens derived from pre-Omicron mutant strains.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Vacinas de Subunidades Antigênicas , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Ensaio de Imunoadsorção Enzimática , Subunidades Proteicas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
17.
Cell Death Dis ; 13(1): 13, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930918

RESUMO

There are nearly 40% of cervical cancer patients showing poor response to neoadjuvant chemotherapy that can be induced by autophagy, however, the underlying mechanism has not yet been fully clarified. We previously found that Sex-determining region of Y-related high-mobility-group box 6 (SOX6), a tumor suppressor gene or oncogene in several cancers, could induce autophagy in cervical cancer. Accordingly, this study aims to investigate the mechanism of SOX6-induced autophagy and its potential significance in the platinum-based chemotherapy of cervical cancer. Firstly, we found that SOX6 could promote autophagy in cervical cancer cells depending on its HMG domain. Mitogen-activated protein kinase kinase kinase kinase-4 (MAP4K4) gene was identified as the direct target gene of SOX6, which was transcriptionally upregulated by binding the HMG domain of SOX6 protein to its double-binding sites within MAP4K4 gene promoter. MAP4K4 mediated the SOX6-induced autophagy through inhibiting PI3K-Akt-mTOR pathway and activating MAPK/ERK pathway. Further, the sensitivity of cervical cancer cells to cisplatin chemotherapy could be reduced by the SOX6-induced autophagy in vitro and in vivo, while such a phenomenon could be turned over by autophagy-specific inhibitor and MAP4K4 inhibitor, respectively. Moreover, cisplatin itself could promote the expression of endogenous SOX6 and subsequently the MAP4K4-mediated autophagy in cervical cancer cells, which might in turn reduce the sensitivity of these cells to cisplatin treatment. These findings uncovered the underlying mechanism and potential significance of SOX6-induced autophagy, and shed new light on the usage of MAP4K4 inhibitor or autophagy-specific inhibitor for sensitizing cervical cancer cells to the platinum-based chemotherapy.


Assuntos
Antineoplásicos/administração & dosagem , Autofagia/genética , Cisplatino/administração & dosagem , Resistencia a Medicamentos Antineoplásicos/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição SOXD/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Técnicas de Inativação de Genes/métodos , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Serina-Treonina Quinases/genética , Fatores de Transcrição SOXD/genética , Transfecção/métodos , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
18.
Artigo em Inglês | MEDLINE | ID: mdl-33388523

RESUMO

The development of versatile mixed-mode stationary phase materials is of important meanings for solving the increasing demands for real sample analysis. Herein, with 2,5-dihydroxyterephthalic acid as the organic ligand and nickel as the metal centre, MOF-74 nanocrystal materials were facilely grafted on the surface of carboxyl-functionalized silica gel via layer-by-layer assembling technique. The structures of the monodisperse MOF-74@SiO2 material were proved by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, elemental analysis, thermogravimetric analysis, and Brunauer-Emmett-Teller specific surface area and pore size analyzer, respectively. Because the introduced 2,5-dihydroxyterephthalic acid is of hydrophilic carboxyl and hydroxyl groups, the packed MOF-74@SiO2 column reveals hydrophilic interaction/reversed-phase mixed-mode retention properties. Compared with commercial C8 column or silica-based column, the MOF-74@SiO2 column shows distrinct separation selectivity in short separation time for polycyclic aromatic hydrocarbons, phenolic compounds and polar sulfonamide compounds. The developed MOF-74@SiO2 column was further successfully applied for the separation and detection of illegal addition of glucocorticoid in children's face cream as well as sulfonamides veterinary drug residues in pure milk. The research provides a simple and convenient approach to prepare multifunctional MOFs-based stationary phase materials.


Assuntos
Cromatografia de Fase Reversa/métodos , Estruturas Metalorgânicas/química , Dióxido de Silício/química , Animais , Resíduos de Drogas/análise , Resíduos de Drogas/isolamento & purificação , Glucocorticoides/análise , Glucocorticoides/isolamento & purificação , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas Metálicas/química , Leite/química , Fenóis/análise , Fenóis/isolamento & purificação , Ácidos Ftálicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Creme para a Pele/química , Sulfonamidas/análise , Sulfonamidas/isolamento & purificação
19.
Front Microbiol ; 11: 604993, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33281803

RESUMO

This study reconstructed molecular networks of human immunodeficiency virus (HIV) transmission history in an area affected by an epidemic of multiple HIV-1 subtypes and assessed the efficacy of strengthened early antiretroviral therapy (ART) and regular interventions in preventing HIV spread. We collected demographic and clinical data of 2221 treatment-naïve HIV-1-infected patients in a long-term cohort in Shenyang, Northeast China, between 2008 and 2016. HIV pol gene sequencing was performed and molecular networks of CRF01_AE, CRF07_BC, and subtype B were inferred using HIV-TRACE with separate optimized genetic distance threshold. We identified 168 clusters containing ≥ 2 cases among CRF01_AE-, CRF07_BC-, and subtype B-infected cases, including 13 large clusters (≥ 10 cases). Individuals in large clusters were characterized by younger age, homosexual behavior, more recent infection, higher CD4 counts, and delayed/no ART (P < 0.001). The dynamics of large clusters were estimated by proportional detection rate (PDR), cluster growth predictor, and effective reproductive number (R e ). Most large clusters showed decreased or stable during the study period, indicating that expansion was slowing. The proportion of newly diagnosed cases in large clusters declined from 30 to 8% between 2008 and 2016, coinciding with an increase in early ART within 6 months after diagnosis from 24 to 79%, supporting the effectiveness of strengthened early ART and continuous regular interventions. In conclusion, molecular network analyses can thus be useful for evaluating the efficacy of interventions in epidemics with a complex HIV profile.

20.
J Virol ; 94(23)2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32938762

RESUMO

The HIV epidemic in China accounts for 3% of the global HIV incidence. We compared the patterns and determinants of interprovincial spread of the five most prevalent circulating types. HIV pol sequences sampled across China were used to identify relevant transmission networks of the five most relevant HIV-1 types (B and circulating recombinant forms [CRFs] CRF01_AE, CRF07_BC, CRF08_BC, and CRF55_01B) in China. From these, the dispersal history across provinces was inferred. A generalized linear model (GLM) was used to test the association between migration rates among provinces and several measures of human mobility. A total of 10,707 sequences were collected between 2004 and 2017 across 26 provinces, among which 1,962 are newly reported here. A mean of 18 (minimum and maximum, 1 and 54) independent transmission networks involving up to 17 provinces were identified. Discrete phylogeographic analysis largely recapitulates the documented spread of the HIV types, which in turn, mirrors within-China population migration flows to a large extent. In line with the different spatiotemporal spread dynamics, the identified drivers thereof were also heterogeneous but are consistent with a central role of human mobility. The comparative analysis of the dispersal dynamics of the five main HIV types circulating in China suggests a key role of large population centers and developed transportation infrastructures as hubs of HIV dispersal. This advocates for coordinated public health efforts in addition to local targeted interventions.IMPORTANCE While traditional epidemiological studies are of great interest in describing the dynamics of epidemics, they struggle to fully capture the geospatial dynamics and factors driving the dispersal of pathogens like HIV as they have difficulties capturing linkages between infections. To overcome this, we used a discrete phylogeographic approach coupled to a generalized linear model extension to characterize the dynamics and drivers of the across-province spread of the five main HIV types circulating in China. Our results indicate that large urbanized areas with dense populations and developed transportation infrastructures are facilitators of HIV dispersal throughout China and highlight the need to consider harmonized country-wide public policies to control local HIV epidemics.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/classificação , China/epidemiologia , Genótipo , Infecções por HIV/transmissão , HIV-1/genética , Humanos , Epidemiologia Molecular , Filogenia , Filogeografia , Saúde Pública
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