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1.
Lancet ; 403(10429): 813-823, 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38387470

RESUMEN

BACKGROUND: Hepatitis E virus (HEV) is a frequently overlooked causative agent of acute hepatitis. Evaluating the long-term durability of hepatitis E vaccine efficacy holds crucial importance. METHODS: This study was an extension to a randomised, double-blind, placebo-controlled, phase-3 clinical trial of the hepatitis E vaccine conducted in Dontai County, Jiangsu, China. Participants were recruited from 11 townships in Dongtai County. In the initial trial, a total of 112 604 healthy adults aged 16-65 years were enrolled, stratified according to age and sex, and randomly assigned in a 1:1 ratio to receive three doses of hepatitis E vaccine or placebo intramuscularly at month 0, month 1, and month 6. A sensitive hepatitis E surveillance system including 205 clinical sentinels, covering the entire study region, was established and maintained for 10 years after vaccination. The primary outcome was the per-protocol efficacy of hepatitis E virus vaccine to prevent confirmed hepatitis E occurring at least 30 days after administration of the third dose. Throughout the study, the participants, site investigators, and laboratory staff remained blinded to the treatment assignments. This study is registered with ClinicalTrials.gov (NCT01014845). FINDINGS: During the 10-year study period from Aug 22, 2007, to Oct 31, 2017, 90 people with hepatitis E were identified; 13 in the vaccine group (0·2 per 10 000 person-years) and 77 in the placebo group (1·4 per 10 000 person-years), corresponding to a vaccine efficacy of 83·1% (95% CI 69·4-91·4) in the modified intention-to-treat analysis and 86·6% (73·0 to 94·1) in the per-protocol analysis. In the subsets of participants assessed for immunogenicity persistence, of those who were seronegative at baseline and received three doses of hepatitis E vaccine, 254 (87·3%) of 291 vaccinees in Qindong at the 8·5-year mark and 1270 (73·0%) of 1740 vaccinees in Anfeng at the 7·5-year mark maintained detectable concentrations of antibodies. INTERPRETATION: Immunisation with this hepatitis E vaccine offers durable protection against hepatitis E for up to 10 years, with vaccine-induced antibodies against HEV persisting for at least 8·5 years. FUNDING: National Natural Science Foundation of China, Fujian Provincial Natural Science Foundation, Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences, and the Fundamental Research Funds for the Central Universities.


Asunto(s)
Hepatitis E , Vacunas contra Hepatitis Viral , Adulto , Humanos , Anticuerpos Antivirales , Hepatitis E/prevención & control , Vacunación
2.
Cogn Process ; 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850444

RESUMEN

Many studies have shown that mental simulation may occur during language comprehension. Supporting evidence is derived from the matching effects in the sentence-picture verification (SPV) task often used to assess mental simulations of object properties, such as size, orientation, and shape. However, mixed results have been obtained regarding object colour, with researchers reporting matching or mismatching effects. This study investigated the impact of colour information clarity within sentences on the process of mental simulation during language comprehension. Employing the SPV task and using novel objects, we examined whether there is a mental simulation of colour after excluding typical/atypical colour bias and how varying levels of colour information clarity in sentences influence the emergence of matching effects at different stages of comprehension. To address these issues, we conducted two experiments. In Experiment 1, the participants read normal sentences and subsequently engaged in picture verification with a novel object after a 500 ms delay. In Experiment 2, the participants encountered sentences containing both clear and unclear colour information and, after either a 0 ms or 1500 ms interval, completed picture verification tasks with a novel object. Null effects were found in the 500 ms condition for normal sentences and the 0 ms condition for unclear colour information sentences. A mismatching effect appeared in the 0 ms condition after clear colour information sentences, and a matching effect appeared in the 1500 ms condition for all sentences. The results indicated that after excluding colour bias, the participants still formed mental simulations of colour during language comprehension. Our results also indicated that ongoing colour simulation with time pressure impacted the participant responses. The participants ignored unclear colour information under time pressure, but without time pressure, they constructed simulations that were as detailed as possible, regardless of whether the implicit colour information in the sentence was clear.

3.
Opt Express ; 31(6): 9404-9415, 2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-37157512

RESUMEN

Thermally induced magnetization switching (TIMS) relying solely on a single laser without any applied magnetic field is a key research direction of current spintronics. Most studies on TIMS so far have focused on GdFeCo with Gd concentration above 20%. In this work, we observe the TIMS at low Gd concentration excited by picosecond laser through atomic spin simulations. The results show that the maximum pulse duration for switching can be increased by an appropriate pulse fluence at the intrinsic damping in low Gd concentrations. At the appropriate pulse fluence, TIMS with pulse duration longer than one picosecond is possible for Gd concentration of only 12%. Our simulation results provide new insights for the exploration of the physical mechanism of ultrafast TIMS.

4.
Molecules ; 27(7)2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35408509

RESUMEN

The behavior of biomolecules in crowded environments remains largely unknown due to the accuracy of simulation models and the limited experimental data for comparison. Here we chose a small crowder of tetraethylene glycol (PEG-4) to investigate the self-crowding of PEG-4 solutions and molecular crowding effects on the structure and diffusion of lysozyme at varied concentrations from dilute water to pure PEG-4 liquid. Two Amber-like force fields of Amber14SB and a99SB-disp were examined with TIP3P (fast diffusivity and low viscosity) and a99SB-disp (slow diffusivity and high viscosity) water models, respectively. Compared to the Amber14SB protein simulations, the a99SB-disp model yields more coordinated water and less PEG-4 molecules, less intramolecular hydrogen bonds (HBs), more protein-water HBs, and less protein-PEG HBs as well as stronger interactions and more hydrophilic and less hydrophobic contacts with solvent molecules. The a99SB-disp model offers comparable protein-solvent interactions in concentrated PEG-4 solutions to that in pure water. The PEG-4 crowding leads to a slow-down in the diffusivity of water, PEG-4, and protein, and the decline in the diffusion from atomistic simulations is close to or faster than the hard sphere model that neglects attractive interactions. Despite these differences, the overall structure of lysozyme appears to be maintained well at different PEG-4 concentrations for both force fields, except a slightly large deviation at 370 K at low concentrations with the a99SB-disp model. This is mainly attributed to the strong intramolecular interactions of the protein in the Amber14SB force field and to the large viscosity of the a99SB-disp water model. The results indicate that the protein force fields and the viscosity of crowder solutions affect the simulation of biomolecules under crowding conditions.


Asunto(s)
Simulación de Dinámica Molecular , Muramidasa , Polietilenglicoles , Proteínas/química , Soluciones , Solventes/química , Agua/química
5.
Nanomedicine ; 32: 102335, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33220508

RESUMEN

Targeted T1-T2 MRI contrast agents, which can eliminate the difficulty of image matching across multiple imaging instruments and permit specific localization of lesions, are promising candidates for more accurate diagnosis of tumors. In this study, ultrasmall Fe@Fe3O4 nanoparticles were designed and synthesized as T1-T2 dual-mode MRI contrast agents for accurate tumor imaging. First, to investigate the influence of nanoparticle size, Fe@Fe3O4 nanoparticles with diameters of 4, 8, and 12 nm were prepared, among which the 8 nm 3-(3,4-dihydroxyphenyl)propionic acid (DHCA)-modified nanoparticles exhibited the optimal T1-T2 dual-mode MRI performance. Next, to develop a tumor-targeted contrast agent, the DHCA-Fe@Fe3O4 nanoparticles were conjugated with the F56 peptide, which targets the vascular endothelial growth factor receptor, and the resulting F56-DHCA-Fe@Fe3O4 nanoparticles were found to exhibit good T1-T2 dual-mode imaging and tumor-targeting performance both in vitro and in vivo, indicating the nanoparticles represent a new research tool for accurate tumor diagnosis.


Asunto(s)
Medios de Contraste/química , Diagnóstico por Imagen , Imagen por Resonancia Magnética , Nanopartículas de Magnetita/química , Neoplasias/diagnóstico por imagen , Tamaño de la Partícula , Resinas Acrílicas/química , Ácidos Cafeicos/química , Células HCT116 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Nanopartículas de Magnetita/ultraestructura , Polietilenglicoles/química , Solubilidad
6.
Antimicrob Agents Chemother ; 64(11)2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-32816724

RESUMEN

Little is known about the influence of extracorporeal membrane oxygenation (ECMO) on the pharmacokinetics (PK) of caspofungin. The aim of this study was to describe population PK of caspofungin in patients with and without ECMO during the postoperative period of lung transplantation (LTx) and to investigate covariates influencing caspofungin PK. We compared ECMO patients with non-ECMO patients, and patients before and after ECMO weaning as self-controls, to analyzed changes in caspofungin PK. Eight serial blood samples were collected from each patient for PK analysis. The population PK of caspofungin was described using nonlinear mixed-effects modeling. Twelve ECMO and 7 non-ECMO lung transplant recipients were enrolled in this study. None of the patients received renal replacement therapy during any part of the study period. The PK of caspofungin was best described by a two-compartment model. There were no significant differences in the PK parameters and concentrations of caspofungin among the ECMO, non-ECMO, and self-control group. In the final covariate model, we found that there was a significant association between the male gender and increased distribution volume, that a higher sequential organ failure assessment score was related to an increase in intercompartmental clearance, and that a longer operative time was related to an increase in clearance and the volume of distribution. ECMO did not have a significant impact on the PK of caspofungin in patients after LTx. Some factors were identified as statistically significant covariates related to the PK of caspofungin; however, their impact on clinical practice of caspofungin needs to be investigated further in more studies. (This study has been registered at ClinicalTrials.gov under identifier NCT03766282.).


Asunto(s)
Oxigenación por Membrana Extracorpórea , Trasplante de Pulmón , Caspofungina , Enfermedad Crítica , Humanos , Masculino , Periodo Posoperatorio , Estudios Retrospectivos
7.
Anal Chem ; 92(12): 8254-8261, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32388978

RESUMEN

Techniques for the qualitative and quantitative detection of H2S in vivo have attracted considerable attention due to the key role of H2S in various physiological and pathological processes. However, in vivo detection strategies for H2S are mainly based on fluorescence imaging, which is limited by its poor tissue penetration. Moreover, the limitations of single-mode probes are amplified in complex physiological environments. Herein, a core-shell Fe3O4@Cu2O nanoparticle was constructed as a magnetic-photoacoustic dual-mode probe for H2S detection in vitro and in vivo based on the in situ response of Cu2O to endogenous H2S in colon tumors. This probe is expected to greatly improve the accuracy of H2S detection in vivo because it employs two detection methods with complementary advantages. The new probe was experimentally applied to the in vivo and in vitro visualization of H2S in mice with colorectal cancer, validating the in situ reaction-activated dual-detection method. This work establishes a simple and efficient dual-mode imaging method based on a novel trigger mechanism. The findings provide a new strategy for colon cancer detection based on the in situ reactions at tumor sites.


Asunto(s)
Neoplasias Colorrectales/diagnóstico por imagen , Sulfuro de Hidrógeno/análisis , Técnicas Fotoacústicas , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cobre/química , Cobre/farmacología , Compuestos Férricos/química , Compuestos Férricos/farmacología , Células HCT116 , Humanos , Fenómenos Magnéticos , Imagen por Resonancia Magnética , Ratones , Ratones Desnudos , Nanopartículas/química , Neoplasias Experimentales/diagnóstico por imagen , Tamaño de la Partícula , Propiedades de Superficie
8.
J Clin Pharm Ther ; 45(5): 1066-1075, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32542736

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: The influence of venovenous extracorporeal membrane oxygenation (VV-ECMO) on the population pharmacokinetics (PPK) of vancomycin in recipients after lung transplantation (LTx) is unknown. We investigated whether VV-ECMO influences vancomycin PPK and determined optimal recommended dosage for patients after LTx. METHODS: We tested vancomycin serum concentration and calculated PPK parameters using NONMEM. To check for any potential influence of ECMO on vancomycin PK, we compared ECMO patients with a non-ECMO patient control group, and patients before and after ECMO weaning as self-control to analysed changes in vancomycin PK. Monte Carlo dosing simulation was conducted to explore vancomycin dosing regimens. RESULTS: Nineteen ECMO and 6 non-ECMO lung transplant recipients were enrolled. Vancomycin serum concentrations did not significantly differ between patients with and without ECMO support. Comparison of separate vancomycin population pharmacokinetic models showed that ECMO patients had smaller peripheral compartment volume of distribution (V2 ) [Estimate (relative standard error, RSE, %) 19.7 (12) vs. 22 (17) L, P = .003] than non-ECMO patients. For treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections with MIC ≤ 0.5 µg/mL, venous infusion of 400 mg vancomycin every 8 hours was recommended. For MRSA infection with MIC ≤ 1 µg/mL, the proposed dosage was 600 mg every 8 hours. WHAT IS NEW AND CONCLUSION: Venovenous extracorporeal membrane oxygenation slightly alters vancomycin PK but does not significantly impact vancomycin serum concentration in patients after LTx. Dose adjustment is not necessary for VV-ECMO support. Specific vancomycin dosing regimens with lower nephrotoxicity may benefit LTx recipients with VV-ECMO.


Asunto(s)
Antibacterianos/farmacocinética , Oxigenación por Membrana Extracorpórea , Trasplante de Pulmón , Vancomicina/farmacocinética , Anciano , Antibacterianos/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Modelos Biológicos , Método de Montecarlo , Dinámicas no Lineales , Estudios Prospectivos , Distribución Tisular , Vancomicina/administración & dosificación
9.
BMC Pulm Med ; 19(1): 237, 2019 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-31818300

RESUMEN

BACKGROUND: The use of extracorporeal membrane oxygenation (ECMO) in awake, spontaneously breathing and non-intubated patients (awake ECMO) may be a novel therapeutic strategy for severe acute respiratory distress syndrome (ARDS) patients. The purpose of this study is to assess the feasibility and safety of awake ECMO in severe ARDS patients receiving prolonged ECMO (> 14 days). METHODS: We describe our experience with 12 consecutive severe ARDS patients (age, 39.1 ± 16.4 years) supported with awake ECMO to wait for native lung recovery during prolonged ECMO treatment from July 2013 to January 2018. Outcomes are reported including the hospital mortality, ECMO-related complications and physiological data on weaning from invasive ventilation. RESULTS: The patients received median 26.0 (15.5, 64.8) days of total ECMO duration in the cohort. The longest ECMO support duration was 121 days. Awake ECMO and extubation was implemented after median 10.2(5.0, 42.9) days of ECMO. Awake ECMO was not associated with increased morbidity. The total invasive ventilation duration, lengths of stay in the ICU and hospital in the cohort were 14.0(12.0, 37.3) days, 33.0(22.3, 56.5) days and 46.5(27.3, 84.8) days, respectively. The hospital mortality rate was 33.3% (4/12) in the cohort. Survivors had more stable respiratory rate and heart rate after extubation when compared to the non-survivors. CONCLUSIONS: With carefully selected patients, awake ECMO is a feasible and safe strategy for severe pulmonary ARDS patients receiving prolonged ECMO support to wait for native lung recovery.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Síndrome de Dificultad Respiratoria/terapia , Adulto , Extubación Traqueal , Femenino , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Recuperación de la Función , Respiración , Respiración Artificial , Síndrome de Dificultad Respiratoria/mortalidad , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
10.
Sensors (Basel) ; 19(24)2019 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-31842415

RESUMEN

In the present work, a novel electrochemical sensor was developed for the detection of trace cadmium with high sensitivity and selectivity in an easy and eco-friendly way. Firstly, a glassy carbon electrode (GCE) was modified with nontoxic sodium carboxymethyl cellulose (CMC) by a simple drop-casting method, which was applied to detect cadmium by differential pulse anodic stripping voltammetry (DPASV) in a solution containing both target cadmium and eco-friendly bismuth ions, based on a quick electro-codeposition of these two metal ions on the surface of the modified electrode (CMC-GCE). Investigated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FT-IR), both CMC (with good film-forming ability) and bismuth (with well-defined stripping signal) were found to be well complexed with target cadmium, leading to vital signal amplification for cadmium detection at a sub-nanomolar level. Under the optimal conditions, the proposed sensor exhibited a good linear stripping signal response to cadmium (Ⅱ) ion, in a concentration range of 0.001 µmol/L-1 µmol/L with a limit of detection of 0.75 nmol/L (S/N = 3). Meanwhile, the results demonstrate that this novel electrochemical sensor has excellent sensitivity and reproducibility, which can be used as a promising detection technique for testing natural samples such as tap water.

11.
Arch Psychiatr Nurs ; 33(2): 149-154, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30927984

RESUMEN

OBJECTIVES: This study examined the incidence of symptomatological post-traumatic stress disorder (PTSD) in bereaved Tibetan adolescents 3 years after the 2010 Yushu earthquake, then to identify possible and relational risk factors of PTSD by a cross-sectional study. METHODS: A total of 867 bereaved Tibetan adolescents seriously impacted by the 2010 earthquake were investigated. Symptomatological PTSD was evaluated by the PTSD Checklist-Civilian Version. And coping styles were evaluated by the Coping Styles Scale. Exposure of trauma to the 2010 Yushu earthquake was evaluated by a checklist about earthquake containing sociodemographic variables. RESULTS: 3 years after the Yushu earthquake, 24.4% of the bereaved Tibetan adolescents had symptomatological PTSD. The results also indicated that coping styles and disaster-related experiences after the 2010 earthquake were connected with PTSD among survivors. When the 2010 earthquake struck, those having symptomatological PTSD were more probably to be buried/injured/amputated, and to witness burial/injury/death, and to have property damage. An individual who adopted positive coping skill was probably to have less symptomatological PTSD. CONCLUSIONS: The results showed that the existence of PTSD in bereaved Tibetan adolescents in the Yushu earthquake was very prevailing after 3 years. Effective psychological rescue work should be carried out, especially targeting bereaved Tibetan adolescents with more severe PTSD.


Asunto(s)
Aflicción , Terremotos/mortalidad , Trastornos por Estrés Postraumático/epidemiología , Sobrevivientes/psicología , Adaptación Psicológica , Adolescente , Niño , China/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Factores de Riesgo , Autoinforme , Encuestas y Cuestionarios , Tibet/etnología
12.
Sensors (Basel) ; 18(9)2018 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-30135387

RESUMEN

A facile cuprous oxide nanoparticles functionalized electro-reduced graphene oxide modified glassy carbon electrode (denoted as Cu2O NPs-ERGO/GCE) was fabricated via a simple physical adsorption and electrochemical reduction approach. Cyclic voltammetry and second-order derivative linear scan voltammetry were used to investigate the electrocatalysis oxidation of vanillin on the Cu2O NPs-ERGO/GCE. The compound yielded a well-defined voltammetric response in 0.1 M H2SO4 at 0.916 V (vs. saturated calomel electrode (SCE)). A linear calibration graph was obtained in the concentration range of 0.1 µM to 10 µM and 10 µM to 100 µM, while the detection limit (S/N = 3) is 10 nM. In addition, the Cu2O NPs-ERGO/GCE presented well anti-interference ability, stability, and reproducibility. It was used to detect vanillin sensitively and rapidly in different commercial food products, and the results were in agreement with the values obtained by high performance liquid chromatography.

13.
Molecules ; 23(10)2018 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-30340409

RESUMEN

Human epidermal growth factor receptor 2 (HER2) is a key tumor marker for several common and deadly cancers. It is of great importance to develop efficient detection methods for its over-expression. In this work, an electrochemical impedance spectroscopy (EIS) method adjustable by anionic porphyrin for HER2 gene detection has been proposed, based on the impedance difference between multi-walled carbon nanotubes (MWCNTs) and DNA. The interesting finding herein is that with the addition of anionic porphyrin, i.e., meso-tetra(4-sulfophenyl)-porphyrin (TSPP), the impedance value obtained at a glass carbon electrode (GCE) modified with MWCNTs and a single stranded DNA (ssDNA), the probe DNA that might be assembled tightly onto MWCNTs through π-π stacking interaction, gets a slight decrease; however, the impedance value from a GCE modified with MWCNTs and a double stranded DNA (dsDNA), the hybrid of the probe DNA with a target DNA, which might be assembled loosely onto MWCNTs for the screening effect of phosphate backbones in dsDNA, gets an obvious decrease. The reason may be that on the one hand, being rich in negative sulfonate groups, TSPP will try to push DNA far away from CNTs surface due to its strong electrostatic repulsion towards DNA; on the other hand, rich in planar phenyl or pyrrole rings, TSPP will compete with DNA for the surface of CNTs since it can also be assembled onto CNTs through conjugative interactions. In this way, the "loosely assembled" dsDNA will be repelled by this anionic porphyrin and released off CNTs surface much more than the "tightly assembled" ssDNA, leading to a bigger difference in the impedance value between dsDNA and ssDNA. Thus, through the amplification effect of TSPP on the impedance difference, the perfectly matched target DNA could be easily determined by EIS without any label. Under the optimized experimental conditions, this electrochemical sensor shows an excellent linear response to target DNA in a concentration range of 2.0 × 10-11⁻2.0 × 10-6 M with a limit of detection (LOD) of 6.34 × 10-11 M (S/N = 3). This abnormally sensitive electrochemical sensing performance resulting from anionic porphyrin for DNA sequences specific to HER2 gene will offer considerable promise for tumor diagnosis and treatment.


Asunto(s)
Técnicas Biosensibles , ADN de Cadena Simple/aislamiento & purificación , Porfirinas/farmacología , Receptor ErbB-2/aislamiento & purificación , Aniones/química , Aniones/farmacología , ADN de Cadena Simple/química , ADN de Cadena Simple/genética , Espectroscopía Dieléctrica , Humanos , Límite de Detección , Nanotubos de Carbono/química , Neoplasias/diagnóstico , Neoplasias/genética , Porfirinas/química , Receptor ErbB-2/química , Receptor ErbB-2/genética
14.
Molecules ; 23(10)2018 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-30304828

RESUMEN

To ensure food quality and safety, developing cost-effective, rapid and precision analytical techniques for quantitative detection of nitrite is highly desirable. Herein, a novel electrochemical sensor based on the sodium cellulose sulfate/poly (dimethyl diallyl ammonium chloride) (NaCS/PDMDAAC) composite film modified glass carbon electrode (NaCS/PDMDAAC/GCE) was proposed toward the detection of nitrite at sub-micromolar level, aiming to make full use of the inherent properties of individual component (biocompatible, low cost, good electrical conductivity for PDMDAAC; non-toxic, abundant raw materials, good film forming ability for NaCS) and synergistic enhancement effect. The NaCS/PDMDAAC/GCE was fabricated by a simple drop-casting method. Electrochemical behaviors of nitrite at NaCS/PDMDAAC/GCE were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Under optimum conditions, the NaCS/PDMDAAC/GCE exhibits a wide linear response region of 4.0 × 10-8 mol·L-1~1.5 × 10-4 mol·L-1 and a low detection 1imit of 43 nmol·L-1. The NaCS/PDMDAAC shows a synergetic enhancement effect toward the oxidation of nitrite, and the sensing performance is much better than the previous reports. Moreover, the NaCS/PDMDAAC also shows good stability and reproducibility. The NaCS/PDMDAAC/GCE was successfully applied to the determination of nitrite in ham sausage with satisfactory results.


Asunto(s)
Carbono/química , Técnicas Electroquímicas , Electrodos , Nitritos/química , Polielectrolitos/química , Electroquímica/métodos , Concentración de Iones de Hidrógeno , Reproducibilidad de los Resultados
15.
Bioconjug Chem ; 26(5): 919-31, 2015 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-25915780

RESUMEN

Sacituzumab govitecan (IMMU-132) is an antibody-drug conjugate (ADC) made from a humanized anti-Trop-2 monoclonal antibody (hRS7) conjugated with the active metabolite of irinotecan, SN-38. In addition to its further characterization, as the clinical utility of IMMU-132 expands to an ever-widening range of Trop-2-expressing solid tumor types, its efficacy in new disease models needs to be explored in a nonclinical setting. Unlike most ADCs that use ultratoxic drugs and stable linkers, IMMU-132 uses a moderately toxic drug with a moderately stable carbonate bond between SN-38 and the linker. Flow cytometry and immunohistochemistry disclosed that Trop-2 is expressed in a wide range of tumor types, including gastric, pancreatic, triple-negative breast (TNBC), colonic, prostate, and lung. While cell-binding experiments reveal no significant differences between IMMU-132 and parental hRS7 antibody, surface plasmon resonance analysis using a Trop-2 CM5 chip shows a significant binding advantage for IMMU-132 over hRS7. The conjugate retained binding to the neonatal receptor, but it lost greater than 60% of the antibody-dependent cell-mediated cytotoxicity activity compared to that of hRS7. Exposure of tumor cells to either free SN-38 or IMMU-132 demonstrated the same signaling pathways, with pJNK1/2 and p21(WAF1/Cip1) upregulation followed by cleavage of caspases 9, 7, and 3, ultimately leading to poly-ADP-ribose polymerase cleavage and double-stranded DNA breaks. Pharmacokinetics of the intact ADC in mice reveals a mean residence time (MRT) of 15.4 h, while the carrier hRS7 antibody cleared at a similar rate as that of the unconjugated antibody (MRT ∼ 300 h). IMMU-132 treatment of mice bearing human gastric cancer xenografts (17.5 mg/kg; twice weekly × 4 weeks) resulted in significant antitumor effects compared to that of mice treated with a nonspecific control. Clinically relevant dosing schemes of IMMU-132 administered either every other week, weekly, or twice weekly in mice bearing human pancreatic or gastric cancer xenografts demonstrate similar, significant antitumor effects in both models. Current Phase I/II clinical trials ( ClinicalTrials.gov , NCT01631552) confirm anticancer activity of IMMU-132 in cancers expressing Trop-2, including gastric and pancreatic cancer patients.


Asunto(s)
Anticuerpos Monoclonales Humanizados/farmacología , Anticuerpos Monoclonales/química , Antígenos de Neoplasias/inmunología , Camptotecina/análogos & derivados , Moléculas de Adhesión Celular/inmunología , Inmunoconjugados/farmacología , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Gástricas/tratamiento farmacológico , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales Humanizados/química , Anticuerpos Monoclonales Humanizados/farmacocinética , Anticuerpos Monoclonales Humanizados/uso terapéutico , Citotoxicidad Celular Dependiente de Anticuerpos/efectos de los fármacos , Antígenos de Neoplasias/metabolismo , Apoptosis/efectos de los fármacos , Camptotecina/química , Camptotecina/farmacocinética , Camptotecina/farmacología , Camptotecina/uso terapéutico , Moléculas de Adhesión Celular/metabolismo , Línea Celular Tumoral , Ensayos Clínicos como Asunto , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Inmunoconjugados/química , Inmunoconjugados/farmacocinética , Inmunoconjugados/uso terapéutico , Irinotecán , Ratones , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Transducción de Señal/efectos de los fármacos , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Mol Cancer ; 13: 53, 2014 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-24606732

RESUMEN

BACKGROUND: Ranpirnase (Rap) is an amphibian ribonuclease with reported antitumor activity, minimal toxicity, and negligible immunogenicity in clinical studies, but the unfavorable pharmacokinetics and suboptimal efficacy hampered its further clinical development. To improve the potential of Rap-based therapeutics, we have used the DOCK-AND-LOCK™ (DNL™) method to construct a class of novel IgG-Rap immunoRNases. In the present study, a pair of these constructs, (Rap)2-E1-(Rap)2 and (Rap)2-E1*-(Rap)2, comprising four copies of Rap linked to the CH3 and CK termini of hRS7 (humanized anti-Trop-2), respectively, were evaluated as potential therapeutics for triple-negative breast cancer (TNBC). METHODS: The DNL-based immunoRNases, (Rap)2-E1-(Rap)2 and (Rap)2-E1*-(Rap)2, were characterized and tested for biological activities in vitro on a panel of breast cancer cell lines and in vivo in a MDA-MB-468 xenograft model. RESULTS: (Rap)2-E1-(Rap)2 was highly purified (>95%), exhibited specific cell binding and rapid internalization in MDA-MB-468, a Trop-2-expressing TNBC line, and displayed potent in vitro cytotoxicity (EC50 ≤ 1 nM) against diverse breast cancer cell lines with moderate to high expression of Trop-2, including MDA-MB-468, BT-20, HCC1806, SKBR-3, and MCF-7. In comparison, structural counterparts of (Rap)2-E1-(Rap)2, generated by substituting hRS7 with selective non-Trop-2-binding antibodies, such as epratuzumab (anti-CD22), were at least 50-fold less potent than (Rap)2-E1-(Rap)2 in MDA-MB-468 and BT-20 cells, both lacking the expression of the cognate antigen. Moreover, (Rap)2-E1-(Rap)2 was less effective (EC50 > 50 nM) in MDA-MB-231 (low Trop-2) or HCC1395 (no Trop-2), and did not show any toxicity to human peripheral blood mononuclear cells. In a mouse TNBC model, a significant survival benefit was achieved with (Rap)2-E1*-(Rap)2 when given the maximal tolerated dose. CONCLUSIONS: A new class of immunoRNases was generated with enhanced potency for targeted therapy of cancer. The promising results from (Rap)2-E1-(Rap)2 and (Rap)2-E1*-(Rap)2 support their further investigation as a potential treatment option for TNBC and other Trop-2-expressing cancers.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Moléculas de Adhesión Celular/metabolismo , Inmunoconjugados/farmacología , Ribonucleasas/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Animales , Antineoplásicos/química , Femenino , Citometría de Flujo , Humanos , Inmunoconjugados/química , Dosis Máxima Tolerada , Ratones , Ratones Desnudos , Terapia Molecular Dirigida , Ribonucleasas/química , Neoplasias de la Mama Triple Negativas/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Neuroreport ; 35(3): 136-142, 2024 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-38109464

RESUMEN

BACKGROUND AND OBJECTIVES: The ability to comprehend and engage in mathematical reasoning is a fundamental cognitive skill, central to problem-solving and critical thinking. However, the intricate cognitive processes underlying mathematical reasoning, particularly in relation to inhibitory control, have garnered increasing attention in recent research. While previous studies have explored this connection, there remains a need for a more comprehensive understanding of the interplay between inhibitory control and mathematical reasoning. This study explored the contribution of response inhibition and semantic inhibition to scientific reasoning by comparing the brain activation of the speeded-reasoning task of mathematical subdomain concepts with that of the Go/Nogo and Stroop tasks. METHOD: Using functional near-infrared spectroscopy, oxygenated hemoglobin (oxy-Hb) was recorded in 28 subjects performing Go/Nogo tasks, Stroop tasks and speeded-reasoning tasks. The study was divided into two parts. In one part, subjects performed the Go/Nogo task and the Stroop task, and in the other part, subjects performed speeded-reasoning tasks. RESULTS: The results showed that the subjects had slower responses and lower accuracy when judging incongruent statements. The concentration of oxy-Hb in the brain region related to inhibition was increased. In addition, the oxy-Hb in reasoning incongruent nonmathematical statements was correlated to the Go/Nogo task, whereas the oxy-Hb in reasoning incongruent mathematical statements was correlated to the Stroop task. CONCLUSION: This result supports the hypothesis that inhibitory control plays a role in the scientific reasoning of mathematical subdomain concepts, and both response inhibition and semantic inhibition are involved in suppressing the interference of mathematical misconceptions.Supplementary Video Abstract, Supplemental digital content 1, http://links.lww.com/WNR/A732.


Asunto(s)
Solución de Problemas , Espectroscopía Infrarroja Corta , Humanos , Espectroscopía Infrarroja Corta/métodos , Encéfalo/metabolismo , Oxihemoglobinas/metabolismo , Atención
18.
Brain Sci ; 14(6)2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38928606

RESUMEN

This study examines the impact of response and semantic inhibition on scientific reasoning using fNIRS data from 30 students (15 male, 15 female). Utilizing Go/Nogo and Stroop-like tasks within a modified speeded-reasoning task, it was found that inhibition significantly influences scientific reasoning. Specifically, slower responses and lower accuracy on incongruent statements were linked to increased activity in bilateral dorsolateral prefrontal cortex (DLPFC) and pre-supplementary motor area (pre-SMA). The research shows that both DLPFC and pre-SMA are associated with overcoming misconceptions in scientific reasoning. The findings suggest that understanding inhibitory mechanisms can enhance educational strategies to improve critical thinking and scientific literacy.

19.
Int J Cardiol ; 399: 131685, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38158133

RESUMEN

BACKGROUND: Suboptimal stent deployment is frequently observed in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PPCI). This study sought to investigate whether these patients could benefit from post-dilatation with respect to post-procedural physiology, microcirculatory resistance, and long-term clinical outcomes. METHODS: This was a retrospective study of consecutive STEMI patients who underwent successful stent implantation during PPCI from February 2016 to November 2021. Post-procedural physiology and microcirculatory resistance were assessed by Murray law-based quantitative flow ratio (µQFR) and angiographic microcirculatory resistance (AMR), respectively. The primary outcome was target vessel failure (TVF), a composite of cardiac death, target vessel-oriented myocardial infarction, and clinically driven target vessel revascularization. RESULTS: A total of 671 patients (671 culprit vessels) were included. Post-dilatation was selectively performed in 430 (64.1%) culprit vessels, resulting in a 0.02 (interquartile range: 0.00-0.05, p < 0.001) increase in post-procedural µQFR but no significant impact on AMR. During a median follow-up of 2.8 years (interquartile range: 1.4-3.0 years), TVF occurred in 47 (7.0%) patients. Post-dilatation demonstrated a trend toward a reduction in TVF (5.3% vs. 10.0%; adjusted hazard ratio: 0.60, 95% confidence interval: 0.33-1.09, p = 0.094), mainly driven by a lower incidence of clinically driven target vessel revascularization (1.6% vs. 4.1%; adjusted hazard ratio: 0.32, 95% confidence interval: 0.11-0.90, p = 0.030). CONCLUSIONS: In STEMI patients undergoing PPCI, selective post-dilatation was associated with improved post-procedural physiological results and a trend toward less TVF events without aggravating microcirculatory resistance.


Asunto(s)
Infarto del Miocardio , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Humanos , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/cirugía , Resultado del Tratamiento , Microcirculación , Estudios Retrospectivos , Dilatación
20.
Hematology ; 29(1): 2307817, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38319083

RESUMEN

OBJECTIVE: To analyze the current treatment status and prognostic regression of the chronic NK cell lymphoproliferative disorder (CLPD-NK). METHODS: We retrospectively analyzed the clinical features, treatment and prognosis of 18 patients with CLPD-NK who were treated at our Hospital between September 2016 and September 2022. RESULTS: Eighteen patients were included: three patients were treated with chemotherapy, five patients underwent immune-related therapy, one patient was treated with glucocorticoids alone, five patients were administered granulocyte colony-stimulating factor, blood transfusion therapy, or anti-infection therapy, followed by observation and follow-up, and four patients were observed without treatment. Fifteen patients survived, including two patients who achieved complete remission (CR) and seven patients who achieved partial remission (PR), of whom one patient progressed to Aggressive NK-cell leukemia (ANKL) and sustained remission after multiple lines of treatment; three patients were not reviewed, of which one patient was still in active disease, three patients developed hemophagocytic syndrome during treatment and eventually died, one of them had positive Epstein-Barr virus (EBV) expression. The 5-years overall survival rate was 83%. CONCLUSION: Most patients with CLPD-NK have inert progression and a good prognosis, whereas some patients have a poor prognosis after progressing to ANKL and combined with hemophagocytic syndrome. Abnormal NK cells invading the center suggest a high possibility of ANKL development, and immunosuppressants and hormones are effective treatments for this disease.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Leucemia Linfocítica Granular Grande , Leucemia , Linfohistiocitosis Hemofagocítica , Trastornos Linfoproliferativos , Humanos , Infecciones por Virus de Epstein-Barr/complicaciones , Herpesvirus Humano 4 , Estudios Retrospectivos , Trastornos Linfoproliferativos/diagnóstico , Trastornos Linfoproliferativos/terapia , Pronóstico , Células Asesinas Naturales/metabolismo , Enfermedad Crónica , Leucemia/metabolismo
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