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1.
Nature ; 625(7993): 148-156, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37993710

RESUMEN

The continuing emergence of SARS-CoV-2 variants highlights the need to update COVID-19 vaccine compositions. However, immune imprinting induced by vaccination based on the ancestral (hereafter referred to as WT) strain would compromise the antibody response to Omicron-based boosters1-5. Vaccination strategies to counter immune imprinting are critically needed. Here we investigated the degree and dynamics of immune imprinting in mouse models and human cohorts, especially focusing on the role of repeated Omicron stimulation. In mice, the efficacy of single Omicron boosting is heavily limited when using variants that are antigenically distinct from WT-such as the XBB variant-and this concerning situation could be mitigated by a second Omicron booster. Similarly, in humans, repeated Omicron infections could alleviate WT vaccination-induced immune imprinting and generate broad neutralization responses in both plasma and nasal mucosa. Notably, deep mutational scanning-based epitope characterization of 781 receptor-binding domain (RBD)-targeting monoclonal antibodies isolated from repeated Omicron infection revealed that double Omicron exposure could induce a large proportion of matured Omicron-specific antibodies that have distinct RBD epitopes to WT-induced antibodies. Consequently, immune imprinting was largely mitigated, and the bias towards non-neutralizing epitopes observed in single Omicron exposures was restored. On the basis of the deep mutational scanning profiles, we identified evolution hotspots of XBB.1.5 RBD and demonstrated that these mutations could further boost the immune-evasion capability of XBB.1.5 while maintaining high ACE2-binding affinity. Our findings suggest that the WT component should be abandoned when updating COVID-19 vaccines, and individuals without prior Omicron exposure should receive two updated vaccine boosters.


Asunto(s)
Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Inmunización Secundaria , Memoria Inmunológica , SARS-CoV-2 , Animales , Humanos , Ratones , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , COVID-19/prevención & control , COVID-19/virología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/inmunología , Epítopos de Linfocito B/inmunología , Memoria Inmunológica/inmunología , SARS-CoV-2/clasificación , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Mutación
2.
Nature ; 614(7948): 521-529, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36535326

RESUMEN

Continuous evolution of Omicron has led to a rapid and simultaneous emergence of numerous variants that display growth advantages over BA.5 (ref. 1). Despite their divergent evolutionary courses, mutations on their receptor-binding domain (RBD) converge on several hotspots. The driving force and destination of such sudden convergent evolution and its effect on humoral immunity remain unclear. Here we demonstrate that these convergent mutations can cause evasion of neutralizing antibody drugs and convalescent plasma, including those from BA.5 breakthrough infection, while maintaining sufficient ACE2-binding capability. BQ.1.1.10 (BQ.1.1 + Y144del), BA.4.6.3, XBB and CH.1.1 are the most antibody-evasive strains tested. To delineate the origin of the convergent evolution, we determined the escape mutation profiles and neutralization activity of monoclonal antibodies isolated from individuals who had BA.2 and BA.5 breakthrough infections2,3. Owing to humoral immune imprinting, BA.2 and especially BA.5 breakthrough infection reduced the diversity of the neutralizing antibody binding sites and increased proportions of non-neutralizing antibody clones, which, in turn, focused humoral immune pressure and promoted convergent evolution in the RBD. Moreover, we show that the convergent RBD mutations could be accurately inferred by deep mutational scanning profiles4,5, and the evolution trends of BA.2.75 and BA.5 subvariants could be well foreseen through constructed convergent pseudovirus mutants. These results suggest that current herd immunity and BA.5 vaccine boosters may not efficiently prevent the infection of Omicron convergent variants.


Asunto(s)
Anticuerpos Antivirales , Deriva y Cambio Antigénico , COVID-19 , Evolución Molecular , Inmunidad Humoral , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Humanos , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Infección Irruptiva/inmunología , Infección Irruptiva/virología , COVID-19/inmunología , COVID-19/virología , Sueroterapia para COVID-19 , SARS-CoV-2/química , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Dominios Proteicos/genética , Dominios Proteicos/inmunología , Deriva y Cambio Antigénico/inmunología , Mutación
3.
Development ; 151(13)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38984541

RESUMEN

The cardiac extracellular matrix (cECM) is fundamental for organ morphogenesis and maturation, during which time it undergoes remodeling, yet little is known about whether mechanical forces generated by the heartbeat regulate this remodeling process. Using zebrafish as a model and focusing on stages when cardiac valves and trabeculae form, we found that altering cardiac contraction impairs cECM remodeling. Longitudinal volumetric quantifications in wild-type animals revealed region-specific dynamics: cECM volume decreases in the atrium but not in the ventricle or atrioventricular canal. Reducing cardiac contraction resulted in opposite effects on the ventricular and atrial ECM, whereas increasing the heart rate affected the ventricular ECM but had no effect on the atrial ECM, together indicating that mechanical forces regulate the cECM in a chamber-specific manner. Among the ECM remodelers highly expressed during cardiac morphogenesis, we found one that was upregulated in non-contractile hearts, namely tissue inhibitor of matrix metalloproteinase 2 (timp2). Loss- and gain-of-function analyses of timp2 revealed its crucial role in cECM remodeling. Altogether, our results indicate that mechanical forces control cECM remodeling in part through timp2 downregulation.


Asunto(s)
Matriz Extracelular , Corazón , Inhibidor Tisular de Metaloproteinasa-2 , Pez Cebra , Animales , Pez Cebra/embriología , Pez Cebra/metabolismo , Matriz Extracelular/metabolismo , Inhibidor Tisular de Metaloproteinasa-2/metabolismo , Inhibidor Tisular de Metaloproteinasa-2/genética , Corazón/embriología , Proteínas de Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Contracción Miocárdica/fisiología , Miocardio/metabolismo , Morfogénesis , Atrios Cardíacos/embriología , Atrios Cardíacos/metabolismo , Fenómenos Biomecánicos , Regulación del Desarrollo de la Expresión Génica , Ventrículos Cardíacos/metabolismo , Ventrículos Cardíacos/embriología
4.
J Virol ; 98(7): e0078624, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38916398

RESUMEN

Severe fever with thrombocytopenia syndrome (SFTS) virus and hantavirus are categorized under the Bunyavirales order. The severe disease progression in both SFTS and hemorrhagic fever with renal syndrome (HFRS) is associated with cytokine storms. This study aimed to explore the differences in cytokine profiles and immune responses between the two diseases. A cross-sectional, single-center study involved 100 participants, comprising 46 SFTS patients, 48 HFRS patients, and 6 healthy controls. The study employed the Luminex cytokine detection platform to measure 48 cytokines. The differences in cytokine profiles and immune characteristics between the two diseases were further analyzed using multiple linear regression, principal component analysis, and random forest method. Among the 48 cytokines tested, 30 showed elevated levels in SFTS and/or HFRS compared to the healthy control group. Furthermore, there were 19 cytokines that exhibited significant differences between SFTS and HFRS. Random forest analysis suggested that TRAIL and CTACK were predictive of SFTS, while IL2Ralpha, MIG, IL-8, IFNalpha2, HGF, SCF, MCP-3, and PDGFBB were more common with HFRS. It was further verified by the receiver operating characteristic with area under the curve >0.8 and P-values <0.05, except for TRAIL. Significant differences were observed in the cytokine profiles of SFTS and HFRS, with TRAIL, IL2Ralpha, MIG, and IL-8 being the top 4 cytokines that most clearly distinguished the two diseases. IMPORTANCE: SFTS and HFRS differ in terms of cytokine immune characteristics. TRAIL, IL-2Ralpha, MIG, and IL-8 were the top 4 that differed markedly between SFTS and HFRS.


Asunto(s)
Citocinas , Fiebre Hemorrágica con Síndrome Renal , Síndrome de Trombocitopenia Febril Grave , Humanos , Fiebre Hemorrágica con Síndrome Renal/inmunología , Fiebre Hemorrágica con Síndrome Renal/virología , Fiebre Hemorrágica con Síndrome Renal/sangre , Citocinas/sangre , Masculino , Síndrome de Trombocitopenia Febril Grave/inmunología , Síndrome de Trombocitopenia Febril Grave/virología , Persona de Mediana Edad , Femenino , Estudios Transversales , Adulto , Anciano , Phlebovirus/inmunología
5.
PLoS Pathog ; 19(12): e1011868, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38117863

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) XBB lineages have achieved dominance worldwide and keep on evolving. Convergent evolution of XBB lineages on the receptor-binding domain (RBD) L455F and F456L is observed, resulting in variants with substantial growth advantages, such as EG.5, FL.1.5.1, XBB.1.5.70, and HK.3. Here, we show that neutralizing antibody (NAb) evasion drives the convergent evolution of F456L, while the epistatic shift caused by F456L enables the subsequent convergence of L455F through ACE2 binding enhancement and further immune evasion. L455F and F456L evade RBD-targeting Class 1 public NAbs, reducing the neutralization efficacy of XBB breakthrough infection (BTI) and reinfection convalescent plasma. Importantly, L455F single substitution significantly dampens receptor binding; however, the combination of L455F and F456L forms an adjacent residue flipping, which leads to enhanced NAbs resistance and ACE2 binding affinity. The perturbed receptor-binding mode leads to the exceptional ACE2 binding and NAb evasion, as revealed by structural analyses. Our results indicate the evolution flexibility contributed by epistasis cannot be underestimated, and the evolution potential of SARS-CoV-2 RBD remains high.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , COVID-19 , Humanos , Enzima Convertidora de Angiotensina 2/genética , SARS-CoV-2/genética , COVID-19/genética , Sueroterapia para COVID-19 , Anticuerpos Neutralizantes
6.
J Infect Dis ; 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39352170

RESUMEN

Severe fever with thrombocytopenia syndrome (SFTS) is a highly fatal disease. Droplet digital polymerase chain reaction (ddPCR) presents unparalleled sensitivity and enables absolute quantification of viral load. In this prospective study, we enrolled 111 patients with SFTS and collected 259 continuous samples. Our findings unveil a robust reverse transcription (RT)-ddPCR method for SFTS with a limit of detection of 2.46 copies/µL (95% CI, 1.50-11.05), surpassing the sensitivity of RT-quantitative polymerase chain reaction at 103.29 copies/µL (95% CI, 79.69-216.35). Longitudinal cohort analysis revealed significantly higher RT-ddPCR detection rates at days 10 to 11, 13 to 14, and ≥15 of the disease course as compared with RT-quantitative polymerase chain reaction (P < .05). Positive RT-ddPCR results were associated with declined platelet and elevated aspartate aminotransferase and lactate dehydrogenase on the same day vs negative RT-ddPCR samples. RT-ddPCR exhibits commendable diagnostic efficacy in SFTS, and it remains detectable in blood samples from patients with an extended disease course. Furthermore, RT-ddPCR correlates with clinical laboratory tests, furnishing valuable reference data for clinical diagnosis.

7.
Chembiochem ; 25(7): e202400043, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38334959

RESUMEN

We report the efficient and site selective modification of non-canonical dehydroamino acids in ribosomally synthesized and post-transationally modified peptides (RiPPs) by ß-amination. The singly modified thiopeptide Thiostrepton showed an up to 35-fold increase in water solubility, and minimum inhibitory concentration (MIC) assays showed that antimicrobial activity remained good, albeit lower than the unmodified peptide. Also the lanthipeptide nisin could be modified using this method.


Asunto(s)
Aminoácidos , Péptidos Antimicrobianos , Procesamiento Proteico-Postraduccional
8.
Opt Express ; 32(4): 6776-6790, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439375

RESUMEN

Independently tunable biaxial color pixels, composed of isolated nanosquare dimers, are demonstrated in this study. These pixels are capable of displaying a full range of colors under a linear-polarization dependent reflection mode. The metasurface is constructed by arranging LiNbO3 nanodimers on a PDMS substrate. By exciting a strong magnetic dipole (MD) resonance and effectively suppressing other multipolar resonances using surface lattice resonances, the researchers achieved a single reflection peak with a bandwidth of less than 9 nm and a reflective efficiency of up to 99%. Additionally, the stretchability of the PDMS substrate allows for active and continuous tuning of the metasurface by up to 40% strain, covering almost 150 nm of the visible light spectrum and enabling changes in reflection color. This metasurface holds potential applications in various fields, such as color displays, data storage, and anti-counterfeiting technologies.

9.
Virol J ; 21(1): 164, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39075510

RESUMEN

Cervical cancer is one of the most common malignant tumours. Human papillomavirus (HPV) infection is the main cause of this cancer so that it could be prevented by screening and early treatment. Developing reginal screen protocols of maximum public health efficacy requires in-depth understandings of local HPV distribution and consequential cancer risks. Therefore, test results of HPV genotyping, cytology testing (TCT) and colposcopy inspection with biopsy were collected in this retrospective research. Data included by this research involved 63,906 women received screen related tests from Shenzhen Baoan Shiyan People's Hospital and the subsidiary institutes between 2017.01 and 2023.05. 10,238 colposcopies were performed in this period collecting 8,716 samples and 814 high-grade CIN were discovered. Within the 763 high-grade CIN cases with both TCT and HPV testing results, 232 were tested cytologically normal but only 30 were negative in HPV test. Besides, the rates of high-grade CIN observed in coinfection were all lower than the estimated rates generated from related single infection. HPV 52, 58 and 16 were found to be the most common types in Baoan, Shenzhen. The result also suggested that HPV coinfections should not increase risk for cervical cancers.


Asunto(s)
Coinfección , Genotipo , Papillomaviridae , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Humanos , Femenino , Infecciones por Papillomavirus/virología , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/complicaciones , Neoplasias del Cuello Uterino/virología , Neoplasias del Cuello Uterino/epidemiología , China/epidemiología , Coinfección/virología , Coinfección/epidemiología , Adulto , Estudios Retrospectivos , Papillomaviridae/genética , Papillomaviridae/aislamiento & purificación , Papillomaviridae/clasificación , Persona de Mediana Edad , Adulto Joven , Displasia del Cuello del Útero/virología , Displasia del Cuello del Útero/epidemiología , Colposcopía , Detección Precoz del Cáncer , Anciano
10.
Cell Commun Signal ; 22(1): 355, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38978049

RESUMEN

BACKGROUND: FMS-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) is a common mutation type in acute myeloid leukemia (AML) and is usually associated with poor patient prognosis. With advancements in molecular diagnostics and the development of tyrosine kinase inhibitors (TKI), the overall survival (OS) of AML patients with FLT3-ITD mutations has been prolonged to some extent, but relapse and drug resistance are still substantial challenges. Ningetinib is a novel TKI against various kinases in relation to tumour pathogenesis and is undergoing clinical trials of lung cancer. In this study, we explored the antitumor activity of ningetinib against AML with FLT3 mutations both in vivo and in vitro. METHODS: Cell proliferation assays were performed in AML cell lines and Ba/F3 cells expressing various FLT3 mutations to validate the antileukemic activity of ningetinib in vitro. Immunoblot assays were used to verify the effect of ningetinib on the FLT3 protein and downstream pathways. Molecular docking and CETSA were used to validate the interaction of ningetinib with target proteins. The survival benefit of ningetinib in vivo was assessed in Ba/F3-FLT3-ITD-, MOLM13, Ba/F3-FLT3-ITD-F691L-, MOLM13-FLT3-ITD-F691L-induced leukemia mouse models. We also used patient-derived primary cells to determine the efficacy of ningetinib. RESULTS: Ningetinib inhibited cell proliferation, blocked the cell cycle, induced apoptosis and bound FLT3 to inhibit its downstream signaling pathways, including the STAT5, AKT and ERK pathways, in FLT3-ITD AML cell lines. In the mouse models with FLT3-ITD and FLT3-ITD-F691L mutation, ningetinib showed superior anti-leukemia activity to existing clinical drugs gilteritinib and quizartinib, significantly prolongating the survival of mice. In addition, ningetinib exhibited activity against patient-derived primary cells harboring FLT3-ITD mutations. CONCLUSION: Overall, our study confirmed the therapeutic role of ningetinib in AML with FLT3-ITD mutations, providing a potential new option for clinically resistant patients.


Asunto(s)
Proliferación Celular , Resistencia a Antineoplásicos , Leucemia Mieloide Aguda , Inhibidores de Proteínas Quinasas , Tirosina Quinasa 3 Similar a fms , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Tirosina Quinasa 3 Similar a fms/genética , Tirosina Quinasa 3 Similar a fms/metabolismo , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Humanos , Animales , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Línea Celular Tumoral , Inhibidores de Proteínas Quinasas/farmacología , Proliferación Celular/efectos de los fármacos , Ratones , Ensayos Antitumor por Modelo de Xenoinjerto , Apoptosis/efectos de los fármacos , Mutación , Transducción de Señal/efectos de los fármacos
11.
J Org Chem ; 89(15): 10831-10843, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-38991973

RESUMEN

Direct construction of gem-difluorinated heterocycles represents a long-standing challenge in organic chemistry. Herein, we developed a transition-metal-free photocatalytic radical addition/cyclization of BrCF2COR with 2-cyanoaryl acrylamides to give gem-difluorinated naphthyridinone scaffolds in moderate to good yields. Furthermore, some natural products were found to be suitable in the reaction system. The easily available substrates, mild reaction conditions, simple operation, and wide functionality tolerance show practical and environmental advantages in this method.

12.
J Org Chem ; 89(6): 4176-4184, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38436198

RESUMEN

A simple and efficient visible-light-promoted selenylation/cyclization of o-alkynyl benzylazides/o-propargyl arylazides have been realized for the practical synthesis of seleno-substituted isoquinolines and quinolines. This strategy provides the synthesis of valuable seleno-substituted isoquinoline and quinoline derivatives via the construction of one C(sp2)-Se bond and one C-N bond within one process.

13.
Org Biomol Chem ; 22(36): 7327-7331, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39175396

RESUMEN

A simple and efficient method to access 4-selenyl-isocoumarin derivatives through visible-light-promoted selenylation/cyclization of o-(1-alkynyl) benzoates has been developed. This transformation is performed under mild conditions and has the advantages of functional group tolerance and broad substrate scope.

14.
Bioorg Chem ; 152: 107733, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39180865

RESUMEN

A series of organoselenium compounds based on the hybridization of artesunate (ART) scaffolds and Se functionalities (-SeCN and -SeCF3) were synthesized. The redox properties of artesunate-SeCN and artesunate-SeCF3 derivatives were conducted by 2, 2-didiphenyl-1-picrylhydrazyl (DPPH), and the results showed that compounds 2c, 2f and 3e have a good free radical scavenging activity. Their cytotoxicity was evaluated against four types of cancer cell lines, SW480 (human colon adenocarcinoma cells), HCT116 (human colorectal adenocarcinoma cells), HepG2 (human hepatocellular carcinoma cells), MCF-7 (human breast cancer cells). The MTT results showed that compared with ART and 5-FU, compound 2c exhibited potent in vitro antiproliferative activity in SW480, HCT116, and MCF-7 cancer cell lines, and was thus chose for further antitumor mechanism investigation. The antitumor mechanism study revealed that compound 2c induced ferroptosis in HCT116 cells by inhibiting the expression of GPX4 protein, accompanying by the up-regulation of intracellular ROS levels. Mitochondria in HCT116 cells exhibit depolarization of mitochondrial membrane potential (MMP) and ultrastructural changes in morphology, which indicated that 2c resulted in mitochondrial dysfunction and ferroptosis. Moreover, 2c could increase the levels of lipid peroxidation and ferrous ion, which further confirm that compound 2c may exert its antitumor effect through ferroptosis. Overall, these results suggest that the artesunate-Se candidates could provide promising new lead derivatives for further potential anticancer drug development.


Asunto(s)
Antineoplásicos , Artesunato , Proliferación Celular , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Ferroptosis , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Humanos , Artesunato/farmacología , Artesunato/síntesis química , Artesunato/química , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Ferroptosis/efectos de los fármacos , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/antagonistas & inhibidores , Proliferación Celular/efectos de los fármacos , Relación Estructura-Actividad , Estructura Molecular , Relación Dosis-Respuesta a Droga , Línea Celular Tumoral , Especies Reactivas de Oxígeno/metabolismo , Compuestos de Organoselenio/farmacología , Compuestos de Organoselenio/química , Compuestos de Organoselenio/síntesis química
15.
Environ Res ; 242: 117717, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37993046

RESUMEN

Understanding the behavior and potential toxicity of copper nanoparticles (nano-Cu) in the aquatic environment is a primary way to assess their environmental risks. In this study, RNA-seq was performed on three different tissues (gills, intestines, and muscles) of zebrafish exposed to nano-Cu, to explore the potential toxic mechanism of nano-Cu on zebrafish. The results indicated that the toxic mechanism of nano-Cu on zebrafish was tissue-specific. Nano-Cu enables the CB1 receptor of the presynaptic membrane of gill cells to affect short-term synaptic plasticity or long-term synaptic changes (ECB-LTD) through DSI and DSE, causing dysfunction of intercellular signal transmission. Imbalance of de novo synthesis of UMP in intestinal cells and its transformation to UDP, UTP, uridine, and uracil, resulted in many functions involved in the pyrimidine metabolic pathway being blocked. Meanwhile, the toxicity of nano-Cu caused abnormal expression of RAD51 gene in muscle cells, which affects the repair of damaged DNA through Fanconi anemia and homologous recombination pathway, thus causing cell cycle disorder. These results provide insights for us to better understand the differences in toxicity of nano-Cu on zebrafish tissues and are helpful for a comprehensive assessment of nano-Cu's effects on aquatic organisms.


Asunto(s)
Nanopartículas , Contaminantes Químicos del Agua , Animales , Cobre/toxicidad , Pez Cebra/metabolismo , Nanopartículas/toxicidad , Ciclo Celular , Contaminantes Químicos del Agua/toxicidad
16.
Child Dev ; 95(4): 1351-1366, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38297823

RESUMEN

The longitudinal person-oriented study aimed to explore profiles, stability, gender differences, and compositional relations of math attitudes by tracking Chinese third graders (Ntotal = 1013, Mage(T1) = 8.92 ± 0.46, Ngirls = 404) in four waves with 1-year intervals. Five profiles and unstable transitional probabilities were identified among the four waves. The relations between enjoyment to confidence and value shifted from reciprocity to enjoyment dominance, but value negatively predicted later enjoyment and confidence. Additionally, boys' advantages were significant in late elementary school (fifth, sixth grades) and girls benefited from initial positive attitudes. These findings suggest that Chinese students' math attitudes in middle childhood are unstable, shaped by internal and external environmental dynamics, and need to be further explored in cross-cultural research.


Asunto(s)
Actitud , Matemática , Instituciones Académicas , Humanos , Femenino , Masculino , Niño , Estudios Longitudinales , China , Factores Sexuales , Placer/fisiología
17.
J Med Virol ; 95(12): e29258, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38054542

RESUMEN

Severe fever with thrombocytopenia syndrome (SFTS) is an acute infectious disease prevalent in East Asia with a high mortality rate (5%-30%). Reverse transcription loop-mediated isothermal amplification (RT-LAMP), a rapid nucleic acid-based diagnostic technique, is a useful alternative for the clinical diagnosis of SFTS, particularly in resource-limited hospitals or rural clinics in SFTS virus-endemic regions. However, the actual clinical sensitivity and specificity of RT-LAMP remain unclear. This study evaluated the field application of RT-LAMP. This prospective field study included 130 patients with laboratory-confirmed SFTS from Yantai, Shandong Province, China. Two sets of RT-LAMP primers were validated, and one set of RT-LAMP assays was optimized for field detection. Nucleic acids of serially collected serum/plasma samples were identified using quantitative reverse transcription polymerase chain reaction (RT-qPCR) and RT-LAMP. In laboratory tests, we optimized the detection time of primer set 2 for the RT-LAMP to 60 min. Notably, the onsite testing of 279 plasma samples from patients with SFTS revealed that the sensitivity and specificity of the test were 81.9% and 96.3%, respectively. We also analyzed samples with different durations of the disease, and our study showed that the sensitivity of RT-LAMP detection at the beginning of admission was 89.92%. Univariate analysis showed that the detection rate of RT-LAMP was similar to that of RT-qPCR in the first 5 days of the disease course and was lower than that of RT-qPCR on Days 6 and 14-15 of the disease course. The positive detection rate in patients aged ≥ 65 years was significantly higher than that in younger age groups. RT-LAMP is a simple, suitable, and rapid clinical detection method of SFTS onsite screening. It is more suitable for screening patients in the early stages of the disease and analyzing samples obtained from patients aged ≥ 65 years before the 6th day of the disease course.


Asunto(s)
Transcripción Reversa , Síndrome de Trombocitopenia Febril Grave , Humanos , Síndrome de Trombocitopenia Febril Grave/diagnóstico , Laboratorios Clínicos , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas de Diagnóstico Molecular/métodos , Sensibilidad y Especificidad , ARN Viral/genética
18.
Opt Lett ; 48(7): 1646-1649, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37221731

RESUMEN

Most ultraviolet (UV) passive optics are currently non-tunable and lack external modulation methods because of the poor tunability of wide-bandgap semiconductor materials in UV working media. This study investigates the excitation of magnetic dipole resonances in the solar-blind UV region by hafnium oxide metasurfaces using elastic dielectric polydimethylsiloxane (PDMS). The near-field interactions between the resonant dielectric elements can be modulated by the mechanical strain of the PDMS substrate, which can flatten the structure's resonant peak beyond the solar-blind UV wavelength range, thereby turning on or off the optical switch in the solar-blind UV region. The device has a facile design and can be used in various applications, such as UV polarization modulation, optical communications, and spectroscopy.

19.
Mol Reprod Dev ; 90(12): 849-860, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37769062

RESUMEN

Epigenetics, including histone modifications and noncoding RNAs, affects abnormal placental function in pre-eclampsia (PE). This study was conducted to explore the role of histone deacetylase 4 (HDAC4) in trophoblast invasion and migration. The expression levels of HDAC4, microRNA (miR)-134-5p, and forkhead box protein M1 (FOXM1) in placentas from PE patients and healthy controls and their correlations were examined. HTR8/SVneo cells were cultured and underwent gene intervention. Then, trophoblast proliferation, invasion, and migration were evaluated by 5-ethynyl-2'deoxyuridine, Transwell, and scratch assays. The enrichments of HDAC4 and acetylated histone H3 at lysine 9 (H3K9Ac) on the miR-134-5p promoter were quantified by chromatin immunoprecipitation. The binding of miR-134-5p to FOXM1 was analyzed by dual-luciferase assay. HDAC4 and FOXM1 were downregulated while miR-134-5p was upregulated in PE placentas. HDAC4 downregulation impaired trophoblast proliferation, invasion, and migration while HDAC4 overexpression played the opposite role. Mechanically, HDAC4 deacetylated H3K9Ac to repress miR-134-5p expression by erasing H3K9Ac, reduced the binding of miR-134-5p to FOXM1, and then promoted FOXM1 transcription. miR-134-5p overexpression or FOXM1 downregulation abrogated the promotive role of HDAC overexpression in trophoblast invasion and migration. Our study unraveled a novel mechanism of trophoblast proliferation, invasion, and migration and proposed that HDAC4 may be a promising target for the treatment of PE.


Asunto(s)
MicroARNs , Preeclampsia , Humanos , Embarazo , Femenino , Placenta/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Preeclampsia/genética , Preeclampsia/metabolismo , Proteína Forkhead Box M1/genética , Proteína Forkhead Box M1/metabolismo , Proliferación Celular/genética , Trofoblastos/metabolismo , Movimiento Celular/genética , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo , Proteínas Represoras
20.
Bioorg Chem ; 131: 106323, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36538834

RESUMEN

Two biotin-polyethylene glycol (PEG)4­diarylidenyl piperidone (DAP) prodrugs, compounds 3a and 3b, were designed as antineoplastic agents and synthesized by coupling biotin to bifluoro- and binitro-substituted DAP derivatives (DAP-F and DAP-NO2) through a PEG4 linker, respectively. The results of the MTT (3-(4, 5)-dimethylthiahiazo (-z-y1)-3, 5-di- phenytetrazoliumromide) assay and a SW480 xenograft model identified compounds 3a and 3b as candidate antitumor agents with good efficacy, limited toxicity, and low resistance, as compared to the original drugs (DAP-F and DAP-NO2), cisplatin, and doxorubicin (dox). The results of a preliminary pharmacokinetic study showed that compounds 3a and 3b slowly released their original drug DAP-F and DAP-NO2 within 12 h after intraperitoneal injection, respectively. Western blot analysis and computer docking simulations indicated that DAP-F, DAP-NO2, and compounds 3a and 3b were indeed inhibitors of signal transducer and activator of transcription 3 (STAT3) and the antitumor effects of compounds 3a and 3b were exerted by sequentially interacting with the SH2-binding domain followed by the DNA-binding domain after releasing the original drugs DAP-F and DAP-NO2, respectively. These results suggest that the targeted prodrug model led to good antitumor efficacy with reduced toxicity, while a dual STAT3-binding model may promote antitumor efficacy and resistance.


Asunto(s)
Antineoplásicos , Profármacos , Humanos , Profármacos/farmacología , Biotina , Dióxido de Nitrógeno , Antineoplásicos/farmacología , Antineoplásicos/química , Doxorrubicina/farmacología , Línea Celular Tumoral
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