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1.
Opt Express ; 32(12): 20695-20705, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859445

RESUMO

We propose an ultrahigh-efficiency and broadband all-optical switching scheme based on coherent perfect absorption (CPA) in linear and nonlinear excitation regimes in a cavity quantum electrodynamics (CQED) system. Two separate atomic transitions are excited simultaneously by two signal fields coupled from two ends of an optical cavity under the collective strong coupling condition. Three polariton eigenstates are produced which can be tuned freely by varying system parameters. The output field intensities of multiple channels are zero when the CPA criterion is satisfied. However, destructive quantum interference can be induced by a free-space weak control laser when it is tuned to be resonant to the polariton state. As a consequence, the CQED system acts as a coherent perfect light absorber/transmitter as the control field is turned on/off the polariton resonances. In particular, the proposed scheme may be used to realize broadband multi-throw all-optical switching in the nonlinear excitation regime. The proposed scheme is useful for constructing all-optical routing, all-optical communication networks and various all-optical logic elements.

2.
Opt Lett ; 49(11): 2878-2881, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824282

RESUMO

We consider a two-dimensional opto-magnomechanical (OMM) system including two optical cavity modes, a magnon mode, a phonon mode, and a collection of two-level atoms. We show how the stationary entanglement between two-level atoms and magnons can be achieved. The presence of two optical cavities leads the atom-magnon entanglement to be achieved in a wide parameter regime. Furthermore, it is shown that one optical cavity can get entangled with magnons, phonons, and the other optical cavity. The entanglement is robust against thermal noise. The work may find applications in building hybrid quantum networks and quantum information processing.

3.
Opt Express ; 31(18): 29491-29503, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710748

RESUMO

We demonstrate a scheme to realize high-efficiency entanglement of two microwave fields in a dual opto-magnomechanical system. The magnon mode simultaneously couples with the microwave cavity mode and phonon mode via magnetic dipole interaction and magnetostrictive interaction, respectively. Meanwhile, the phonon mode couples with the optical cavity mode via radiation pressure. Each magnon mode and optical cavity mode adopts a strong red detuning driving field to activate the beam splitter interaction. Therefore, the entangled state generated by the injected two-mode squeezed light in optical cavities can be eventually transferred into two microwave cavities. A stationary entanglement E a 1 a 2 =0.54 is obtained when the input two-mode squeezed optical field has a squeezing parameter r = 1. The entanglement E a 1 a 2 increases as the squeezing parameter r increases, and it shows the flexible tunability of the system. Meanwhile, the entanglement survives up to an environmental temperature about 385 mK, which shows high robustness of the scheme. The proposed scheme provides a new mechanism to generate entangled microwave fields via magnons, which enables the degree of the prepared microwave entanglement to a more massive scale. Our result is useful for applications which require high entanglement of microwave fields like quantum radar, quantum navigation, quantum teleportation, quantum wireless fidelity (Wi-Fi) network, etc.

4.
Acta Pharmacol Sin ; 42(7): 1090-1100, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33116250

RESUMO

Hepatic fibrosis is a disease characterized by excessive deposition of extracellular matrix (ECM) in the liver. Activation of hepatic stellate cells (HSCs) is responsible for most of ECM production. Oxidative stress and reactive oxygen species (ROS) may be important factors leading to liver fibrosis. NADPH oxidase 4 (NOX4) is the main source of ROS in hepatic fibrosis, but the mechanism by which NOX4 regulates oxidative stress is not fully understood. ß-Arrestin2 is a multifunctional scaffold protein that regulates receptor endocytosis, signaling and trafficking. In this study, we investigated whether ß-arrestin2 regulated oxidative stress in hepatic fibrosis. Both ß-arrestin2 knockout (Arrb2 KO) mice and wild-type mice were intraperitoneally injected with carbon tetrachloride (CCl4) to induce hepatic fibrosis. Arrb2 KO mice showed significantly attenuated liver fibrosis, decreased ROS levels and NOX4 expression, and reduced collagen levels in their livers. In vitro, NOX4 knockdown significantly inhibited ROS production, and decreased expression of alpha-smooth muscle actin in angiotensin II-stimulated human HSC cell line LX-2. Through overexpression or depletion of ß-arrestin2 in LX-2 cells, we revealed that decreased ß-arrestin2 inhibited ROS levels and NOX4 expression, and reduced collagen production; it also inhibited activation of ERK and JNK signaling pathways. These results demonstrate that ß-arrestin2 deficiency protects against liver fibrosis by downregulating ROS production through NOX4. This effect appears to be mediated by ERK and JNK signaling pathways. Thus, targeted inhibition of ß-arrestin2 might reduce oxidative stress and inhibit the progression of liver fibrosis.


Assuntos
Cirrose Hepática/metabolismo , NADPH Oxidase 4/metabolismo , Estresse Oxidativo/fisiologia , beta-Arrestina 2/deficiência , Animais , Tetracloreto de Carbono , Colágeno/metabolismo , Regulação para Baixo/fisiologia , Técnicas de Inativação de Genes , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Metaloproteinase 13 da Matriz/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Inibidor Tecidual de Metaloproteinase-1/metabolismo , beta-Arrestina 2/genética
5.
Biochem Biophys Res Commun ; 522(2): 485-491, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31780259

RESUMO

Acute liver injury can be caused by oxidative stress within a short period and is a common pathway to many liver diseases. The liver is vulnerable to reactive oxygen species (ROS) and free radical-mediated disorders. ß-arrestin2 was initially discovered to be a negative regulator of G protein-coupled receptor signaling. Recently, ß-arrestin2 has been found to act as a multifunctional adaptor protein and play new roles in regulating intracellular signaling networks. However, the role of ß-arrestin2 in the pathogenesis of acute liver injury is unclear. In this study, we hypothesize that ß-arrestin2 regulates acute liver injury via modulation of oxidative stress. ß-arrestin2 knockout mice were used to investigate the impacts of ß-arrestin2 on carbon tetrachloride (CCl4)-induced acute liver injury and oxidative stress. Results here suggested that ß-arrestin2 deficiency decreased serum activities of aminotransferase and alleviated liver injury induced by CCl4 injection as compared with wildtype mice. ß-arrestin2 knockout mice exhibited stronger tolerance in oxidative stress compared with wild-type mice, which was demonstrated by decreased ROS level and increased superoxide dismutase (SOD) and glutathione (GSH) in the liver. Furthermore, ß-arrestin2 deficiency significantly inhibited NOX4 (a major source of ROS) expression and the activation of the extracellular regulated kinase (ERK) and, c-Jun NH2-terminal kinase (JNK) pathways. These results suggest that ß-arrestin2 deficiency protects against CCl4-induced acute liver injury through attenuating oxidative damage and decreased ERK and JNK phosphorylation.


Assuntos
Fígado/lesões , Fígado/metabolismo , Substâncias Protetoras/metabolismo , beta-Arrestina 2/metabolismo , Animais , Antioxidantes/metabolismo , Tetracloreto de Carbono , Deleção de Genes , Glutationa/metabolismo , Fígado/patologia , Fígado/fisiopatologia , Sistema de Sinalização das MAP Quinases , Malondialdeído/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , NADPH Oxidase 4/metabolismo , Especificidade de Órgãos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
6.
Fish Shellfish Immunol ; 94: 889-895, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31546039

RESUMO

Short-term feed deprivation or fasting is commonly experienced by aquaculture fish species and may be caused by seasonal variations, production strategies, or diseases. To assess the effects of fasting on the resistance of Nile tilapia to Streptococcus agalactiae infection, vaccinated and unvaccinated fish were fasted for zero, one, three, and seven days prior to infection. The cortisol levels of both vaccinated and unvaccinated fish first decreased and then increased significantly as fasting time increased. Liver glycogen, triglycerides, and total cholesterol decreased significantly after seven days of fasting, but glucose content did not vary significantly between fish fasted for three and seven days. Hexokinase (HK) and pyruvate kinase (PK) activity levels were lowest after seven days of fasting, while phosphoenolpyruvate carboxykinase (PEPCK) activity levels varied in opposition to those of HK and PK. Serum superoxide dismutase (SOD) and catalase (CAT) activity levels first increased and then decreased as fasting time increased; SOD activity was highest after three days of fasting. Interleukin-1beta (IL-1ß) and IL-6 mRNA expression levels first increased and then decreased significantly, peaking after three days of fasting. However, suppressor of cytokine signaling-1 (SOCS-1) mRNA expression levels were in opposition to those of IL-1ß and IL-6. Specific antibody levels did not vary significantly among unvaccinated fish fasted for different periods. Although specific antibody level first increased and then decreased in the vaccinated fish as fasting duration increased, there were no significant differences in the survival rates of fasted vaccinated fish after challenge with S. agalactiae. The final survival rates of vaccinated fish fasted for zero, one, three, and seven days were 86.67 ±â€¯5.44%, 80.00 ±â€¯3.14%, 88.89 ±â€¯6.28%, and 84.44 ±â€¯8.32%, respectively. Among the unvaccinated fish, the survival rate was highest (35.56 ±â€¯3.14%) in the fish fasted for three days and lowest (6.67 ±â€¯3.14%) in the fish fasted for seven days. Therefore, our results indicated that short-term fasting (three days) prior to an infection might increase the resistance of unvaccinated Nile tilapia to S. agalactiae.


Assuntos
Ciclídeos/imunologia , Resistência à Doença/fisiologia , Doenças dos Peixes/imunologia , Privação de Alimentos/fisiologia , Animais , Masculino , Distribuição Aleatória , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia
7.
Fish Shellfish Immunol ; 88: 111-116, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30797068

RESUMO

The rabbitfish Siganus oramin is resistant to the ciliate parasite Cryptocaryon irritans. L-amino acid oxidase (LAAO) protein from rabbitfish can kill C. irritans in vitro, however, other immune defence mechanisms against C. irritans remains unknown. Here, we generated transcriptomes of rabbitfish skin at 12 h post infection (PI) by C. irritans. The transcriptomes contained 238, 504, 124 clean reads were obtained and then assembled into 258,869 unigenes with an average length of 621 bp and an N50 of 833 bp. Among them, we obtained 418 differentially expressed genes (DEGs) in the skin of rabbitfish under C. irritans infection and control conditions, including 336 significantly up-regulated genes and 82 significantly down-regulated genes. Seven immune-related categories with 32 differentially expressed immune genes were obtained using Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. DEGs included innate immune molecules, such as LAAO, antimicrobial peptide, lysozyme g, as well as complement components, chemokines and chemokine receptors, NOD-like receptor/Toll-like receptor signaling pathway molecules, antigen processing and T/B cell activation and proliferation molecules. We further validated the expression results of nine immune-related DEGs using quantitative real-time PCR. This study provides new insights into the early immune response of a host that is resistant to C. irritans.


Assuntos
Infecções por Cilióforos/imunologia , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Animais , Doenças dos Peixes/imunologia , Peixes/genética , Peixes/imunologia , Peixes/virologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Hymenostomatida/fisiologia , Imunidade Inata/genética
8.
Parasitol Res ; 118(6): 1731-1739, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31049695

RESUMO

The aim of this study was to evaluate the effect of trypanosomes on cultured largemouth bass (Micropterus salmoides) and describe the taxonomic identification of the parasite. The effects of the parasite on M. salmoides were examined based on clinical symptoms, hemograms, histopathology, and serum biochemistry. Diseased fish showed typical clinical symptoms of trypanosomiasis, which included lethargy, anorexia, and histopathological lesions in the liver, head kidney, and spleen. The serum of diseased fish had significantly lower concentrations of glucose, triglyceride, and low-density lipoprotein, and significantly higher alanine transaminase (ALT), aspartate transaminase (AST), and lactate dehydrogenase (LDH) activities. The morphology of the trypanosomes was also analyzed using light microscopy, and their 18S rDNA sequence was analyzed to establish genetic relationships with other known strains. We found that the trypomastigote form of the trypanosomes from M. salmoides was similar to those isolated from Pelteobagrus fulvidraco. The trypanosomes had a slender and narrow body with a relatively long free flagellum, not well-developed undulating membrane, and an oval kinetoplast located near the subterminal posterior end of the body. The 18S rDNA sequences of the trypanosome from M. salmoides had the highest similarity (99.8%) with that of P. fulvidraco, suggesting they are identical species. Based on the differences in morphological characteristics and 18S rDNA sequence compared to trypanosomes isolated from other freshwater fish, it is considered as a new species and we propose the name Trypanosoma micropteri n. sp.


Assuntos
Doenças dos Peixes/parasitologia , Trypanosoma/classificação , Tripanossomíase/veterinária , Animais , Bass/parasitologia , Peixes-Gato/parasitologia , China , DNA Ribossômico/genética , Água Doce/parasitologia , Filogenia , Trypanosoma/genética , Trypanosoma/isolamento & purificação , Tripanossomíase/parasitologia , Tripanossomíase/patologia
9.
Int J Mol Sci ; 19(5)2018 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-29734668

RESUMO

Among a great variety of cell surface receptors, the largest superfamily is G protein-coupled receptors (GPCRs), also known as seven-transmembrane domain receptors. GPCRs can modulate diverse signal-transduction pathways through G protein-dependent or independent pathways which involve β-arrestins, G protein receptor kinases (GRKs), ion channels, or Src kinases under physiological and pathological conditions. Recent studies have revealed the crucial role of GPCRs in the tumorigenesis and the development of cancer metastasis. We will sum up the functions of GPCRs—particularly those coupled to chemokines, prostaglandin, lysophosphatidic acid, endothelin, catecholamine, and angiotensin—in the proliferation, invasion, metastasis, and angiogenesis of hepatoma cells and the development of hepatocellular carcinoma (HCC) in this review. We also highlight the potential avenues of GPCR-based therapeutics for HCC.


Assuntos
Carcinogênese/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Receptores Acoplados a Proteínas G/genética , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , Metástase Neoplásica , Transdução de Sinais/genética , beta-Arrestinas/genética
10.
Physiol Plant ; 156(3): 311-22, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26294083

RESUMO

Vitamin K epoxide reductase (VKOR) exists widely in the chloroplasts of higher plants and plays important roles in redox regulation. However, investigations of plant VKOR function have primarily focused on VKOR from Arabidopsis, and knowledge concerning this function is therefore quite limited. In this study, Solanum lycopersicum was used to study the function of VKOR. Transcription level analysis revealed that SlVKOR (S. lycopersicum VKOR) expression was upregulated by salt or drought stress. To further investigate the function of SlVKOR in plants, we generated sense and antisense transgenic S. lycopersicum homozygotes at T2 generation plants. Compared with wild-type (WT) plants, the leaf disks of the SlVKOR overexpression plants retained a much higher percentage of chlorophyll after salt or drought treatment, whereas the antisense transgenic plants displayed an opposite response. The overexpressed plants displayed lower levels of H2O2 and superoxide anion radical (O2(·-)) than WT plants, whereas antisense plants accumulated considerably more H2O2 and O2(·-). The activities of reactive oxygen scavenger enzymes, including superoxide dismutase, peroxidase, ascorbate peroxidase and catalase, were consistent with the accumulation of reactive oxygen species. Based on these results, we suggest that SlVKOR is involved in resistance to salt or drought stress.


Assuntos
Pressão Osmótica , Homologia de Sequência de Aminoácidos , Solanum lycopersicum/enzimologia , Estresse Fisiológico , Vitamina K Epóxido Redutases/metabolismo , Adaptação Fisiológica , Antioxidantes/metabolismo , Secas , Escherichia coli/metabolismo , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Solanum lycopersicum/genética , Viabilidade Microbiana , Plantas Geneticamente Modificadas , RNA Antissenso/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Superóxidos/metabolismo
11.
Physiol Plant ; 154(1): 28-38, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25171375

RESUMO

Arabidopsis lumen thiol oxidoreductase 1 (LTO1) - the At4g35760 gene product - was previously found to be related to reactive oxygen species (ROS) accumulation. Here, we show that ROS accumulated in a mutant Arabidopsis line (lto1-2, mutant of LTO1/AtVKOR) under osmotic stress at a higher level than that observed in wild-type and transgenic complemented plants of the lto1-2 mutant (lto1-2C, transgenic complemented plants of lto1-2). Because ROS accumulation in osmotic stress is triggered by abscisic acid (ABA), an ABA-responsive gene, Annexin 1 (AnnAt1), was selected to study the response. Osmotic stress or exogenous ABA can significantly upregulate the transcription of AnnAt1 in wild-type and lto1-2C plants. Only a slight change in the transcriptional abundance of AnnAt1 was observed under osmotic stress in the lto1-2 mutant, but exogenous ABA application could increase the expression of AnnAt1, which suggested that exogenous ABA had a partial complementation role. Because the transcription of AnnAt1 is regulated by ABRE (ABA-responsive elements) binding proteins (AREBs)/ABRE binding factors (ABFs), the expression of AREBs/ABFs was also analyzed. The transcription of AREBs/ABFs in the lto1-2 mutant was not induced by osmotic stress but was significantly upregulated by exogenous ABA, which significantly differs from the wild-type and lto1-2C plant responses. Similarly, the expression of another ABA-responsive gene, RD29B (responsive to desiccation stress gene 29B), in the lto1-2 mutant was also upregulated by exogenous ABA. The partial complementation of mutants by ABA indicated that the ABA signal transduction pathway was not significantly affected in the lto1-2 mutant. Taken together, these results suggest that LTO1 is involved in ABA-mediated response to osmotic stress, possibly by affecting the biosynthesis of endogenous ABA.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Pressão Osmótica , Tilacoides/metabolismo , Vitamina K Epóxido Redutases/metabolismo , Anexinas/metabolismo , Arabidopsis/genética , Proteínas e Peptídeos de Choque Frio/metabolismo , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio/metabolismo , Elementos Reguladores de Transcrição , Vitamina K Epóxido Redutases/genética
12.
Biochemistry (Mosc) ; 79(5): 440-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24954595

RESUMO

Homologs of vitamin K epoxide reductase (VKOR) exist widely in plants. However, only VKOR of Arabidopsis thaliana has been the subject of many studies to date. In the present study, the coding region of a VKOR from Solanum lycopersicum (JF951971 in GenBank) was cloned; it contained a membrane domain (VKOR domain) and an additional soluble thioredoxin-like (Trx-like) domain. Bioinformatic analysis showed that the first 47 amino acids in the N-terminus should act as a transit peptide targeting the protein to the chloroplast. Western blot demonstrated that the protein is localized in thylakoid membrane with the Trx-like domain facing the lumen. Modeling of three-dimensional structure showed that SlVKOR has a similar conformation with Arabidopsis and cyanobacterial VKORs, with five transmembrane segments in the VKOR domain and a typical Trx-like domain in the lumen. Functional assay showed that the full-length of SlVKOR with Trx-like domain without the transit peptide could catalyze the formation of disulfide bonds. Similar transit peptides at the N-terminus commonly exist in plant VKORs, most of them targeting to chloroplast according to prediction. Comparison of sequences and structures from different plants indicated that all plant VKORs possess two domains, a transmembrane VKOR domain and a soluble Trx-like domain, each having four conservative cysteines. The cysteines were predicted to be related to the function of catalyzing the formation of disulfide bonds.


Assuntos
Proteínas de Plantas/metabolismo , Solanum lycopersicum/metabolismo , Vitamina K Epóxido Redutases/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Cloroplastos/metabolismo , Clonagem Molecular , Biologia Computacional , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/classificação , Estrutura Terciária de Proteína , Vitamina K Epóxido Redutases/química , Vitamina K Epóxido Redutases/classificação
13.
ScientificWorldJournal ; 2014: 278305, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24592160

RESUMO

The problem of absolute stability of Lur'e systems with sector and slope restricted nonlinearities is revisited. Novel time-domain and frequency-domain criteria are established by using the Lyapunov method and the well-known Kalman-Yakubovich-Popov (KYP) lemma. The criteria strengthen some existing results. Simulations are given to illustrate the efficiency of the results.


Assuntos
Conceitos Matemáticos
14.
Sci Rep ; 14(1): 19583, 2024 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-39179639

RESUMO

A high baseline NLR is associated with a poor prognosis of immunotherapy in patients with advanced HCC. As anti-tumour immune activation takes time, early dynamic changes in NLR may serve as a biomarker for predicting immunotherapy response. We conducted a retrospective study in which we enrolled 209 patients with aHCC who received ICIs (training cohort: N = 121, validation cohort: N = 88). In the training cohort, we categorized the patients based on the early changes in their NLR. Specifically, we defined patients as NLR Stable-Responder, NLR Responder and NLR Non-Responder. We compared the outcomes of these three patient groups using survival analysis. Additionally, we shortened the observation period to 6 weeks and validated the findings in the validation cohort. In the training cohort, early dynamic changes in NLR (HR 0.14, 95%CI 0.03-0.65, p = 0.012, HR 0.19, 95%CI 0.07-0.54, p = 0.002; HR 0.21, 95%CI 0.10-0.42, p < 0.001, HR 0.40, 95%CI 0.23-0.69, p = 0.001), PD-L1 < 1% (HR 5.36, 95%CI 1.12-25.66, p = 0.036; HR 2.98, 95%CI 1.51-5.91, p = 0.002) and MVI (HR 3.52, 95%CI 1.28-9.69, p = 0.015; HR 1.99, 95%CI 1.14-3.47, p = 0.015) were identified as independent predictors of OS and PFS. In the validation cohort, when the observation period was reduced to 6 weeks, early NLR changes still have predictive value. Early dynamic changes in NLR may be an easily defined, cost-effective, non-invasive biomarker to predict aHCC response to ICIs.


Assuntos
Carcinoma Hepatocelular , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Prognóstico , Neutrófilos/imunologia , Adulto , Biomarcadores Tumorais
15.
Front Immunol ; 15: 1358306, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38665910

RESUMO

Background: Targeted and Immunotherapy has emerged as a new first-line treatment for advanced hepatocellular carcinoma (aHCC). To identify the appropriate targeted and immunotherapy, we implemented next generation sequencing (NGS) to provide predictive and prognostic values for aHCC patients. Methods: Pretreatment samples from 127 HCC patients were examined for genomic changes using 680-gene NGS, and PD-L1 expression was detected by immunohistochemistry. Demographic and treatment data were included for analyses of links among treatment outcomes, drug responses, and genetic profiles. A prognostic index model for predicting benefit from treatment was constructed, taking into account of biomarkers, including TP53, TERT, PD-L1, and tumor mutation burden (TMB) as possible independent prognostic factors. Results: The multivariate Cox regression analyses showed that PD-L1≥1% (HR 25.07, 95%CI 1.56 - 403.29, p=0.023), TMB≥5Mb (HR 86.67, 95% CI 4.00 - 1876.48, p=0.004), TERT MU (HR 84.09, 95% CI 5.23 - 1352.70, p=0.002) and TP53 WT (HR 0.01, 95%CI 0.00 - 0.47, p=0.022) were independent risk factors for overall survival (OS), even after adjusting for various confounders. A prognostic nomogram for OS was developed, with an area under the ROC curve of 0.91, 0.85, and 0.98 at 1-, 2-, and 3- year, respectively, and a prognostic index cutoff of 1.2. According to the cutoff value, the patients were divided into the high-risk group (n=29) and low-risk group (n=98). The benefit of targeted and immunotherapy in the low-risk group was not distinguishable according to types of agents. However, treatment of Atezolizumab and Bevacizumab appeared to provide longer OS in the high-risk group (12 months vs 9.2, 9, or 5 months for other treatments, p<0.001). Conclusion: The prognostic model constructed by PD-L1, TMB, TERT, and TP53 can identify aHCC patients who would benefit from targeted and immunotherapy, providing insights for the personalized treatment of HCC.


Assuntos
Biomarcadores Tumorais , Carcinoma Hepatocelular , Sequenciamento de Nucleotídeos em Larga Escala , Imunoterapia , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Biomarcadores Tumorais/genética , Imunoterapia/métodos , Idoso , Prognóstico , Adulto , Antígeno B7-H1/genética , Terapia de Alvo Molecular , Valor Preditivo dos Testes , Mutação
16.
Front Immunol ; 15: 1329634, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38304429

RESUMO

Background: Immunotherapy based on immune checkpoint inhibitors (ICIs) has become the first-line treatment for unresectable hepatocellular carcinoma (uHCC). However, only a small portion of patients are responsive to ICIs. It is important to identify the patients who are likely to benefit from ICIs in clinical practice. We aimed to examine the significance of serum IL-6 and CRP levels in predicting the effectiveness of ICIs for uHCC. Methods: We retrospectively recruited 222 uHCC patients who received ICIs treatment (training cohort: 124 patients, validation cohort: 98 patients). In the training cohort, patients are categorized into the response group (R) and no-response group (NR). The levels of serum IL-6 and CRP were compared between the two groups. Internal validation was performed in the validation cohort. Survival analysis was carried out using the Kaplan-Meier method and Cox proportional hazard regression model. The nomograms were developed and assessed using the consistency index (C-index) and calibration curve. Results: Serum levels of IL-6 and CRP were significantly lower in the R group than in the NR group (9.94 vs. 36.85 pg/ml, p< 0.001; 9.90 vs. 24.50 mg/L, p< 0.001, respectively). An ROC curve was employed to identify the optimal cut-off values for IL-6 and CRP in both groups, resulting in values of 19.82 pg/ml and 15.50 mg/L, respectively. Multivariate Cox regression analysis revealed that MVI (HR 1.751, 95%CI 1.059-2.894, p=0.029; HR 1.530, 95%CI 0.955-2.451, p=0.077), elevated IL-6 (HR 1.624, 95%CI 1.016-2.596, p=0.043; HR 2.146, 95%CI 1.361-3.383, p =0.001) and high CRP (HR 1.709, 95%CI 1.041-2.807, p=0.034; HR 1.846, 95%CI 1.128-3.022, p = 0.015) were independent risk factors for PFS and OS, even after various confounders adjustments. Nomograms are well-structured and validated prognostic maps constructed from three variables, as MVI, IL6 and CRP. Conclusion: Low levels of IL-6 and CRP have a positive correlation with efficacy for uHCC patients receiving ICIs.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Nomogramas , Carcinoma Hepatocelular/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Interleucina-6 , Neoplasias Hepáticas/tratamento farmacológico , Estudos Retrospectivos
17.
Pest Manag Sci ; 80(4): 1991-2000, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38092527

RESUMO

BACKGROUND: Mosquitoes are vectors of various diseases, posing significant health threats worldwide. Chemical pesticides, particularly pyrethroids like deltamethrin, are commonly used for mosquito control, but the emergence of resistant mosquito populations has become a concern. In the deltamethrin-resistant (DR) strain of Culex pipiens pallens, the highly expressed cytochrome P450 9 J34 (CYP9J34) gene is believed to play a role in resistance, yet the underlying mechanism remains unclear. RESULTS: Quantitative polymerase chain reaction with reverse transcription (qRT-PCR) analysis revealed that the expression of CYP9J34 was 14.6-fold higher in DR strains than in deltamethrin-susceptible (DS) strains. The recombinant production of CYP9J34 protein of Cx. pipiens pallens showed that the protein could directly metabolize deltamethrin, yielding the major metabolite 4'-OH deltamethrin. Through dual luciferase reporter assays and RNA interference, the transcription factor homeobox protein B-H2-like (B-H2) was identified to modulate the expression of the CYP9J34 gene, contributing to mosquito resistance to deltamethrin. CONCLUSIONS: Our findings demonstrate that the CYP9J34 protein could directly degrade deltamethrin, and the transcription factor B-H2 could regulate CYP9J34 expression, influencing the resistance of mosquitoes to deltamethrin. © 2023 Society of Chemical Industry.


Assuntos
Culex , Inseticidas , Piretrinas , Animais , Inseticidas/farmacologia , Inseticidas/metabolismo , Fator B do Complemento/metabolismo , Resistência a Inseticidas/genética , Piretrinas/farmacologia , Piretrinas/metabolismo , Nitrilas/farmacologia , Nitrilas/metabolismo , Culex/genética , Culex/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo
18.
Environ Pollut ; 345: 123531, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38341059

RESUMO

Occupational exposure to carcinogens of increasing cancer risk have been extensively suggested. A robust assessment of these evidence is needed to guide public policy and health care. We aimed to classify the strength of evidence for associations of 13 occupational carcinogens (OCs) and risk of cancers. We searched PubMed and Web of Science up to November 2022 to identify potentially relevant studies. We graded the evidence into convincing, highly suggestive, suggestive, weak, or not significant according to a standardized classification based on: random-effects p value, number of cancer cases, 95% confidence interval of largest study, heterogeneity between studies, 95% prediction interval, small study effect, excess significance bias and sensitivity analyses with credibility ceilings. The quality of meta-analysis was evaluated by AMSTAR 2. Forty-eight articles yielded 79 meta-analyses were included in current umbrella review. Evidence of associations were convincing (class I) or highly suggeastive (class II) for asbestos exposure and increasing risk of lung cancer among smokers (RR = 8.79, 95%CI: 5.81-13.25 for cohort studies and OR = 8.68, 95%CI: 5.68-13.24 for case-control studies), asbestos exposure and increasing risk of mesothelioma (RR = 4.61, 95%CI: 2.57-8.26), and formaldehyde exposure and increasing risk of sinonasal cancer (RR = 1.68, 95%CI: 1.38-2.05). Fifteen associations were supported by suggestive evidence (class III). In summary, the current umbrella review found strong associations between: asbestos exposure and increasing risk of lung cancer among smokers; asbestos exposure and increasing risk of mesothelioma; and formaldehyde exposure and higher risk of sinonasal cancer. Other associations might be genuine, but substantial uncertainty remains.


Assuntos
Amianto , Formaldeído/efeitos adversos , Neoplasias Pulmonares , Mesotelioma , Exposição Ocupacional , Hipersensibilidade Respiratória , Humanos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/epidemiologia , Carcinógenos/toxicidade , Exposição Ocupacional/efeitos adversos
19.
Parasit Vectors ; 17(1): 222, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38745242

RESUMO

BACKGROUND: Culex pipiens pallens is a well-known mosquito vector for several diseases. Deltamethrin, a commonly used pyrethroid insecticide, has been frequently applied to manage adult Cx. pipiens pallens. However, mosquitoes can develop resistance to these insecticides as a result of insecticide misuse and, therefore, it is crucial to identify novel methods to control insecticide resistance. The relationship between commensal bacteria and vector resistance has been recently recognized. Bacteriophages (= phages) are effective tools by which to control insect commensal bacteria, but there have as yet been no studies using phages on adult mosquitoes. In this study, we isolated an Aeromonas phage vB AhM-LH that specifically targets resistance-associated symbiotic bacteria in mosquitoes. We investigated the impact of Aeromonas phage vB AhM-LH in an abundance of Aeromonas hydrophila in the gut of Cx. pipiens pallens and its effect on the status of deltamethrin resistance. METHODS: Phages were isolated on double-layer agar plates and their biological properties analyzed. Phage morphology was observed by transmission electron microscopy (TEM) after negative staining. The phage was then introduced into the mosquito intestines via oral feeding. The inhibitory effect of Aeromonas phage vB AhM-LH on Aeromonas hydrophila in mosquito intestines was assessed through quantitative real-time PCR analysis. Deltamethrin resistance of mosquitoes was assessed using WHO bottle bioassays. RESULTS: An Aeromonas phage vB AhM-LH was isolated from sewage and identified as belonging to the Myoviridae family in the order Caudovirales using TEM. Based on biological characteristics analysis and in vitro antibacterial experiments, Aeromonas phage vB AhM-LH was observed to exhibit excellent stability and effective bactericidal activity. Sequencing revealed that the Aeromonas phage vB AhM-LH genome comprises 43,663 bp (51.6% CG content) with 81 predicted open reading frames. No integrase-related gene was detected in the vB AH-LH genome, which marked it as a potential biological antibacterial. Finally, we found that Aeromonas phage vB AhM-LH could significantly reduce deltamethrin resistance in Cx. pipiens pallens, in both the laboratory and field settings, by decreasing the abundance of Aeromonas hydrophila in their midgut. CONCLUSIONS: Our findings demonstrate that Aeromonas phage vB AhM-LH could effectively modulate commensal bacteria Aeromonas hydrophila in adult mosquitoes, thus representing a promising strategy to mitigate mosquito vector resistance.


Assuntos
Aeromonas hydrophila , Bacteriófagos , Culex , Resistência a Inseticidas , Nitrilas , Piretrinas , Animais , Aeromonas hydrophila/virologia , Aeromonas hydrophila/efeitos dos fármacos , Culex/virologia , Culex/microbiologia , Bacteriófagos/fisiologia , Bacteriófagos/isolamento & purificação , Bacteriófagos/genética , Piretrinas/farmacologia , Nitrilas/farmacologia , Inseticidas/farmacologia , Mosquitos Vetores/virologia , Mosquitos Vetores/microbiologia , Feminino
20.
RSC Med Chem ; 15(8): 2663-2676, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39149092

RESUMO

There is significant value in developing multifunctional drug delivery systems with high therapeutic efficiency for diagnosing and treating tumors. In this study, we synthesized the ATP-triggered and pH-sensitive material ZIF-90 using the liquid-phase diffusion method. This was done to load 10-hydroxycamptothecin (HCPT), and the FA-PEG-NH2 conjugate was synthesized through an amidation reaction. We further modified the HCPT@ZIF-90 nanocomposite by employing the Schiff base reaction to create the HCPT@ZIF-90-PEG-FA nanomaterial. Drug loading test results revealed a high HCPT drug loading of up to 22.3% by weight. In the drug release experiment, the cumulative drug release of HCPT@ZIF-90 nanomaterials in pH 5.4 and ATP solutions was the highest after 72 hours. The active targeted delivery of FA and the dual-responsive release of HCPT by ZIF-90 significantly enhanced the therapeutic effect of HCPT@ZIF-90-PEG-FA on human colon cancer cells (HCT116). In the cytotoxicity test, when 100 µg mL-1 of HCPT@ZIF-90-PEG-FA was incubated with cells, the cell survival rate was 16.61 ± 1.19%, significantly lower than that of the other experimental groups. This result indicates that HCPT@ZIF-90-PEG-FA exhibits excellent anti-tumor activity. Cell cycle experiments have shown that HCPT@ZIF-90-PEG-FA may inhibit the proliferation of cancer cells by blocking DNA synthesis and halting cell cycle progression. Cell uptake experiments showed that HCPT@ZIF-90-PEG-FA was mainly present in the cytoplasm of HCT1116 cells, indicating successful cellular entry of the drug to exert its therapeutic effect. In vivo experiments also demonstrated that HCPT@ZIF-90-PEG-FA nanomaterials can effectively eradicate HCT116 tumors. The utilization of the nano-drug carrier ZIF-90, along with the modification with PEG-FA, notably improved the therapeutic efficacy of HCPT. These results suggest that the system, with its active targeted delivery of FA and dual-responsive release of HCPT, could present a novel strategy for treating human colorectal cancer.

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