Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 131
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Infect Dis ; 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38234283

RESUMEN

BACKGROUND: Soluble inflammatory factors have been investigated in the cerebrospinal fluid (CSF) of neurosyphilis patients with low-throughput technology. This study aimed to illustrate the characteristics of soluble factors profiles in CSF of neurosyphilis patients. METHODS: We measured the concentrations of 45 cytokines/chemokines/growth factors in CSF from 112 untreated syphilis cases, including latent syphilis (LS), asymptomatic neurosyphilis (ANS), meningeal neurosyphilis (MNS), meningovascular neurosyphilis (MVNS), paralytic dementia (PD) and ocular syphilis (OS). RESULTS: Thirty-three differentially expressed soluble factors (DeSFs) were categorized into three clusters. DeSFs scores of cluster 1 and 2 (DeSFS1 and DeSFS2) were positively correlated with elevated neopterin and neurofilament light subunit (NF-L) concentration, respectively. DeSFs scores of cluster 3 were positively correlated with WBC, protein, NF-L and neopterin. Patients with LS, ANS, and OS exhibited an overall lower abundance of DeSFs. PD patients exhibited significantly increased levels of cluster 1 and 3, and the highest total DeSFs score, while patients with MNS and MVNS showed enhanced levels of cluster 2. ROC analysis revealed that DeSFS1 effectively discriminated PD, and DeSFS2 discriminated MNS/MVNS with high accuracy. CONCLUSIONS: Patients with neurosyphilis at different stages have distinctive patterns of soluble factors in CSF, which are correlated with immune status and neuronal damage.

2.
Clin Immunol ; 263: 110227, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38643891

RESUMEN

T-DM1 (Trastuzumab Emtansine) belongs to class of Antibody-Drug Conjugates (ADC), where cytotoxic drugs are conjugated with the antibody Trastuzumab to specifically target HER2-positive cancer cells. Platelets, as vital components of the blood system, intricately influence the immune response to tumors through complex mechanisms. In our study, we examined platelet surface proteins in the plasma of patients before and after T-DM1 treatment, categorizing them based on treatment response. We identified a subgroup of platelets with elevated expression of CD63 and CD9 exclusively in patients with favorable treatment responses, while this subgroup was absent in patients with poor responses. Another noteworthy discovery was the elevated expression of CD36 in the platelet subgroups of patients exhibiting inadequate responses to treatment. These findings suggest that the expression of these platelet surface proteins may be correlated with the prognosis of T-DM1 treatment. These indicators offer valuable insights for predicting the therapeutic response to T-DM1 and may become important references in future clinical practice, contributing to a better understanding of the impact of ADC therapies and optimizing personalized cancer treatment strategies.


Asunto(s)
Ado-Trastuzumab Emtansina , Plaquetas , Neoplasias de la Mama , Humanos , Femenino , Plaquetas/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/sangre , Ado-Trastuzumab Emtansina/uso terapéutico , Persona de Mediana Edad , Trastuzumab/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Adulto , Anciano , Maitansina/uso terapéutico , Maitansina/análogos & derivados
3.
Small ; 20(24): e2310636, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38412413

RESUMEN

Several DNA-damaging antitumor agents, including ruthenium complexes, induce immunogenic cell death (ICD). In this study, an arginyl-glycyl-aspartic acid (RGD) peptide-modified carboline ruthenium complex (KS-Ru) is synthesized as a chemotherapeutic nanodrug and an ICD inducer. The RGD peptide, an integrin ligand, provides tumor-specific targeting and promotes self-assembly of the KS-Ru complex. The pH-responsive self-assembly is assessed through transmission and scanning electron microscopy. Additionally, in vitro cytotoxic activity and anti-metastasis ability are evaluated using MTT and Transwell assays, respectively, along with cellular immunofluorescence staining and imaging flow cytometry. The ability of the complex to inhibit primary tumor formation and lung metastasis in vivo is evaluated using Lewis lung cancer and A549 xenograft models. Furthermore, the tumor immune microenvironment is evaluated using single-cell flow mass cytometry. KS-Ru translocates to the nucleus, causing DNA damage and inducing ICD. Within the lysosomes, KS-Ru self-assembled into nanoflowers, leading to lysosomal swelling and apoptosis. Notably, the as-synthesized pH-dependent ruthenium nanomedicine achieves dual functionality-chemotherapy and immunotherapy. Moreover, the pH-responsive self-assembly of KS-Ru enables simultaneous mechanisms in the lysosome and nucleus, thereby lowering the likelihood of drug resistance. This study provides valuable insight for the design of novel ruthenium-based nanoantitumor drugs.


Asunto(s)
ADN , Muerte Celular Inmunogénica , Lisosomas , Rutenio , Rutenio/química , Rutenio/farmacología , Concentración de Iones de Hidrógeno , Humanos , Muerte Celular Inmunogénica/efectos de los fármacos , Lisosomas/metabolismo , Lisosomas/efectos de los fármacos , ADN/química , Animales , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Células A549 , Línea Celular Tumoral
4.
Small ; : e2400661, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597688

RESUMEN

Renewable energy-driven conversion of CO2 to value-added fuels and chemicals via electrochemical CO2 reduction reaction (CO2RR) technology is regarded as a promising strategy with substantial environmental and economic benefits to achieve carbon neutrality. Because of its sluggish kinetics and complex reaction paths, developing robust catalytic materials with exceptional selectivity to the targeted products is one of the core issues, especially for extensively concerned Cu-based materials. Manipulating Cu species by anionic coordination is identified as an effective way to improve electrocatalytic performance, in terms of modulating active sites and regulating structural reconstruction. This review elaborates on recent discoveries and progress of Cu-based CO2RR catalytic materials enhanced by anionic coordination control, regarding reaction paths, functional mechanisms, and roles of different non-metallic anions in catalysis. Finally, the review concludes with some personal insights and provides challenges and perspectives on the utilization of this strategy to build desirable electrocatalysts.

5.
Virol J ; 21(1): 77, 2024 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-38555445

RESUMEN

PURPOSE: The purpose of this study was to investigate immunological variations between a group that received the hepatitis B vaccine and a non-vaccine group. We focused on a cohort that achieved HBsAg seroclearance after Peg-IFNα treatment of CHB. METHODS: We enrolled twenty-eight individuals who achieved HBsAg seroclearance after Peg-IFNα treatment. They were divided into two groups: a vaccine group (n = 14) and a non-vaccine group (n = 14). We assessed lymphocyte subpopulations, B cell- and T cell-surface costimulatory/inhibitory factors, cytokines and immunoglobulin levels were detected at different time points to explore immune-function differences between both groups. RESULTS: The seroconversion rate in the vaccine group at 24 weeks post-vaccination was 100%, which was significantly higher (p = 0.006) than that of the non-vaccine group (50%). Additionally, more individuals in the vaccine group exhibited anti-HBs levels exceeding 100 IUs/L and 300 IUs/L compared to the non-vaccine group (p < 0.05). The vaccine group demonstrated significantly increase total B cells and class-switched B cells at 24 weeks and plasma cells, CD80+B cells, Tfh cells, and ICOS+Tfh cell at 12 weeks, compared with baseline levels (p < 0.05). Conversely, Bregs (CD24+CD27+ and CD24+CD38high) decreased significantly at 24 weeks (p < 0.05). None of the above changes were statistically significance in the non-vaccine group (p > 0.05). Total IgG increased significantly in the vaccine group, and IL-2, IL-5, and IL-6 concentrations increased significantly at week 24 (p < 0.05). Differences in various types of cytokines and immunoglobulins in the plasma of the non-vaccine group were not significant (p > 0.05). Anti-HBs titers positively correlated with Th1/Th2 cells at 24 weeks (r = 0.448 and 0.458, respectively, p = 0.022 and 0.019, respectively), and negatively with CD24+CD38highBreg cells (r = -0.402, p = 0.042). CONCLUSIONS: After achieving HBsAg seroclearance through Peg-IFNα treatment for CHB, administering the hepatitis B vaccine significantly increased anti-HBs-seroconversion rates and antibody levels. We also observed significant immunological differences between the vaccine and non-vaccine groups. Specifically, the vaccine group exhibited significant increases in B cells, plasma cells, and Tfh cells, while Breg levels was significantly lower. These immunological changes are likely conducive to the production of anti-HBs antibodies. However, in the non-vaccine group, the observed changes were not significantlly significant.


Asunto(s)
Antígenos de Superficie de la Hepatitis B , Hepatitis B Crónica , Humanos , Interferón-alfa/uso terapéutico , Seroconversión , Hepatitis B Crónica/tratamiento farmacológico , Vacunas contra Hepatitis B/uso terapéutico , Citocinas , Anticuerpos contra la Hepatitis B , Vacunación , Inmunidad , Antígenos e de la Hepatitis B , Antivirales/uso terapéutico , Polietilenglicoles/uso terapéutico
6.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1378-1387, 2024 Mar.
Artículo en Zh | MEDLINE | ID: mdl-38621986

RESUMEN

This paper aims to study the pharmacokinetic differences of twelve effective constituents(succinic acid, neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, protocatechuic aldehyde, caffeic acid, 5-O-ferulogeninic acid, p-coumaric acid, nuciferine, quercetin, oleanolic acid, and ursolic acid) in Qihe Fenqing Yin in normal and diabetic rats. The diabetic rat model was established by a high-fat diet combined with intraperitoneal injection of streptozocin. A UHPLC-QTRAP-MS/MS method was established for the simultaneous determination of 12 constituents in the plasma of normal rats and model rats after a single intragastric administration of Qihe Fenqing Yin. The results show that the established analytical method has a good linear relationship with the 12 components, and the specificity, accuracy, precision, and stability meet the requirements. The computational pharmacokinetic parameters are fitted by DAS 3.2.8 software, and the results show that the half-life time(t_(1/2)) of the other nine components in the model group was longer than that in the normal group except for caffeic acid, 5-O-ferulogeninic acid, and oleanolic acid. The area under curve(AUC_(0-t)) of cryptochlorogenic acid, p-coumaric acid, ursolic acid, and oleanolic acid increases compared with the normal group. Meanwhile, mean residence time(MRT) delays. The "double peaks" of quercetin and nuciferine in the normal group are not observed in the model group, suggesting that the pharmacokinetic parameters of the drugs in the disease state are significantly different.


Asunto(s)
Ácidos Cafeicos , Ácidos Cumáricos , Diabetes Mellitus Experimental , Medicamentos Herbarios Chinos , Ácido Oleanólico , Ratas , Animales , Ratas Sprague-Dawley , Quercetina , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Medicamentos Herbarios Chinos/farmacocinética
7.
Angew Chem Int Ed Engl ; 63(26): e202405594, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38638107

RESUMEN

Conjugated polymers with tailorable composition and microarchitecture are propitious for modulating catalytic properties and deciphering inherent structure-performance relationships. Herein, we report a facile linker engineering strategy to manipulate the electronic states of metallophthalocyanine conjugated polymers and uncover the vital role of organic linkers in facilitating electrocatalytic oxygen reduction reaction (ORR). Specifically, a set of cobalt phthalocyanine conjugated polymers (CoPc-CPs) wrapped onto carbon nanotubes (denoted CNTs@CoPc-CPs) are judiciously crafted via in situ assembling square-planar cobalt tetraaminophthalocyanine (CoPc(NH2)4) with different linear aromatic dialdehyde-based organic linkers in the presence of CNTs. Intriguingly, upon varying the electronic characteristic of organic linkers from terephthalaldehyde (TA) to 2,5-thiophenedicarboxaldehyde (TDA) and then to thieno/thiophene-2,5-dicarboxaldehyde (bTDA), their corresponding CNTs@CoPc-CPs exhibit gradually improved electrocatalytic ORR performance. More importantly, theoretical calculations reveal that the charge transfer from CoPc units to electron-withdrawing linkers (i.e., TDA and bTDA) drives the delocalization of Co d-orbital electrons, thereby downshifting the Co d-band energy level. Accordingly, the active Co centers with more positive valence state exhibit optimized binding energy toward ORR-relevant intermediates and thus a balanced adsorption/desorption pathway that endows significant enhancement in electrocatalytic ORR. This work demonstrates a molecular-level engineering route for rationally designing efficient polymer catalysts and gaining insightful understanding of electrocatalytic mechanisms.

8.
Neuroimage ; 284: 120452, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37949258

RESUMEN

Pain empathy is a complex form of psychological inference that enables us to understand how others feel in the context of pain. Since pain empathy may be grounded in our own pain experiences, it exhibits huge inter-individual variability. However, the neural mechanisms behind the individual differences in pain empathy and its association with pain perception are still poorly understood. In this study, we aimed to characterize brain mechanisms associated with individual differences in pain empathy in adult participants (n = 24). The 32-channel electroencephalography (EEG) was recorded at rest and during a pain empathy task, and participants viewed static visual stimuli of the limbs submitted to painful and nonpainful stimulation to solicit empathy. The pain sensitivity of each participant was measured using a series of direct current stimulations. In our results, the N2 of Fz and the LPP of P3 and P4 were affected by painful pictures. We found that both delta and alpha bands in the frontal and parietal cortex were involved in the regulation of pain empathy. For the delta band, a close relationship was found between average power, either in the resting or task state, and individual differences in pain empathy. It suggested that the spectral power in Fz's delta band may reflect subjective pain empathy across individuals. For the alpha band, the functional connectivity between Fz and P3 under painful picture stimulation was correlated to individuals' pain sensitivity. It indicated that the alpha band may reflect individual differences in pain sensitivity and be involved in pain empathy processing. Our results suggested the distinct role of the delta and alpha bands of EEG signals in pain empathy processing and may deepen our understanding of the neural mechanisms underpinning pain empathy.


Asunto(s)
Empatía , Individualidad , Adulto , Humanos , Electroencefalografía , Dolor , Percepción del Dolor/fisiología
9.
Neurobiol Dis ; 187: 106314, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37783233

RESUMEN

Poly (ADP-ribose) polymerase-1 (PARP-1) is the most extensively studied member of the PARP superfamily, with its primary function being the facilitation of DNA damage repair processes. Parthanatos is a type of regulated cell death cascade initiated by PARP-1 hyperactivation, which involves multiple subroutines, including the accumulation of ADP-ribose polymers (PAR), binding of PAR and apoptosis-inducing factor (AIF), release of AIF from the mitochondria, the translocation of the AIF/macrophage migration inhibitory factor (MIF) complex, and massive MIF-mediated DNA fragmentation. Over the past few decades, the role of PARP-1 in central nervous system health and disease has received increasing attention. In this review, we discuss the biological functions of PARP-1 in neural cell proliferation and differentiation, memory formation, brain ageing, and epigenetic regulation. We then elaborate on the involvement of PARP-1 and PARP-1-dependant parthanatos in various neuropathological processes, such as oxidative stress, neuroinflammation, mitochondrial dysfunction, excitotoxicity, autophagy damage, and endoplasmic reticulum (ER) stress. Additional highlight contains PARP-1's implications in the initiation, progression, and therapeutic opportunities for different neurological illnesses, including neurodegenerative diseases, stroke, autism spectrum disorder (ASD), multiple sclerosis (MS), epilepsy, and neuropathic pain (NP). Finally, emerging insights into the repurposing of PARP inhibitors for the management of neurological diseases are provided. This review aims to summarize the exciting advancements in the critical role of PARP-1 in neurological disorders, which may open new avenues for therapeutic options targeting PARP-1 or parthanatos.


Asunto(s)
Trastorno del Espectro Autista , Enfermedades Neurodegenerativas , Parthanatos , Humanos , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Poli(ADP-Ribosa) Polimerasas/metabolismo , Ribosa , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Epigénesis Genética , Enfermedades Neurodegenerativas/patología
10.
Appl Opt ; 62(23): 6147-6155, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37707082

RESUMEN

In this paper, a Gaussian-beam-coupled color polarization interference (CCPI) sensor with an adjustable digital Gaussian filter was proposed theoretically in the frequency domain. The coupling principle of a traditional color polarization interference (CPI) sensor and a Gaussian beam was investigated, and sensitivity optimization was then implemented. The formation of a doublet is related to the shape of a CPI curve, expected wavelength, and FWHM of the Gaussian beam. Based on the calculated results, the angle between the two polarizers and the obliquity of the wave plate are the two most significant adjusting parameters. The sensitivity of a CCPI sensor is approximately twofold higher than that of a traditional CPI sensor. The sensing range is also related to the FWHM of the Gaussian beam and a larger FWHM usually means a wider sensing range. We also found that the sensitivity would reach a maximum when the incident angle is near the total internal reflection angle. Besides, a longer incident wavelength usually corresponds to a higher sensitivity and the sensitivity could reach as high as 9270 nm/refractive index unit when the resonance wavelength is 977.40 nm.

11.
Nano Lett ; 22(17): 7136-7143, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-36018249

RESUMEN

Single-beam super-resolution microscopy, also known as superlinear microscopy, exploits the nonlinear response of fluorescent probes in confocal microscopy. The technique requires no complex purpose-built system, light field modulation, or beam shaping. Here, we present a strategy to enhance this technique's spatial resolution by modulating excitation intensity during image acquisition. This modulation induces dynamic optical nonlinearity in upconversion nanoparticles (UCNPs), resulting in variations of nonlinear fluorescence response in the obtained images. The higher orders of fluorescence response can be extracted with a proposed weighted finite difference imaging algorithm from raw fluorescence images to generate an image with higher resolution than superlinear microscopy images. We apply this approach to resolve single nanoparticles in a large area, improving the resolution to 132 nm. This work suggests a new scope for the development of dynamic nonlinear fluorescent probes in super-resolution nanoscopy.


Asunto(s)
Colorantes Fluorescentes , Nanopartículas , Algoritmos , Microscopía Confocal/métodos
12.
Anal Bioanal Chem ; 414(18): 5671-5681, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35482065

RESUMEN

The analysis of natural and anthropogenic nanomaterials (NMs) in the environment is challenging and requires methods capable to identify and characterise structures on the nanoscale regarding particle number concentrations (PNCs), elemental composition, size, and mass distributions. In this study, we employed single particle inductively coupled plasma-mass spectrometry (SP ICP-MS) to investigate the occurrence of NMs in the Melbourne area (Australia) across 63 locations. Poisson statistics were used to discriminate between signals from nanoparticulate matter and ionic background. TiO2-based NMs were frequently detected and corresponding NM signals were calibated with an automated data processing platform. Additionally, a method utilising a larger mass bandpass was developed to screen for particulate high-mass elements. This procedure identified Pb-based NMs in various samples. The effects of different environmental matrices consisting of fresh, brackish, or seawater were mitigated with an aerosol dilution method reducing the introduction of salt into the plasma and avoiding signal drift. Signals from TiO2- and Pb-based NMs were counted, integrated, and subsequently calibrated to determine PNCs as well as mass and size distributions. PNCs, mean sizes, particulate masses, and ionic background levels were compared across different locations and environments.


Asunto(s)
Nanoestructuras , Titanio , Plomo , Tamaño de la Partícula , Análisis Espectral , Titanio/análisis , Agua
13.
BMC Public Health ; 22(1): 2007, 2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-36324110

RESUMEN

BACKGROUND: Local environmental factors are associated with health and healthcare-seeking behaviors. However, there is a paucity in the literature documenting the link between air pollution and healthcare-seeking behaviors. This study aimed to address the gap in the literature through a cross-sectional study of domestic migrants in China. METHODS: Data were extracted from the 2017 China Migrants Dynamic Survey (n = 10,051) and linked to the official air pollution indicators measured by particulate matter (PM2.5 and PM10) and air quality index (AQI) in the residential municipalities (n = 310) of the study participants over the survey period. Probit regression models were established to determine the association between air pollution and refraining from visiting health facilities after adjustment for variations in the predisposing, enabling and needs factors. Thermal inversion intensity was adopted as an instrumental variable to overcome potential endogeneity. RESULTS: One unit (µg/m3) increase in monthly average PM2.5 was associated with 1.8% increase in the probability of refraining from visiting health facilities. The direction and significance of the link remained unchanged when PM2.5 was replaced by AQI or PM10. Higher probability of refraining from visiting health facilities was also associated with overwork (ß = 0.066, p = 0.041) and good self-related health (ß = 0.171, p = 0.006); whereas, lower probability of refraining from visiting health facilities was associated with short-distance (inter-county) migration (ß=-0.085, p = 0.048), exposure to health education (ß=-0.142, p < 0.001), a high sense of local belonging (ß=-0.082, p = 0.018), and having hypertension/diabetes (ß=-0.169, p = 0.005). CONCLUSION: Air pollution is a significant predictor of refraining from visiting health facilities in domestic migrants in China.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Migrantes , Humanos , Estudios Transversales , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Material Particulado/efectos adversos , Material Particulado/análisis , China/epidemiología , Instituciones de Salud , Exposición a Riesgos Ambientales/análisis
14.
Small ; 17(17): e2008062, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33733581

RESUMEN

Fluorescent nanoparticles are widely utilized in a large range of nanoscale imaging and sensing applications. While ultra-small nanoparticles (size ≤10 nm) are highly desirable, at this size range, their photostability can be compromised due to effects such as intensity fluctuation and spectral diffusion caused by interaction with surface states. In this article, a facile, bottom-up technique for the fabrication of sub-10-nm hexagonal boron nitride (hBN) nanoparticles hosting photostable bright emitters via a catalyst-free hydrothermal reaction between boric acid and melamine is demonstrated. A simple stabilization protocol that significantly reduces intensity fluctuation by ≈85% and narrows the emission linewidth by ≈14% by employing a common sol-gel silica coating process is also implemented. This study advances a promising strategy for the scalable, bottom-up synthesis of high-quality quantum emitters in hBN nanoparticles.

15.
Neurochem Res ; 46(3): 523-534, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33394222

RESUMEN

Voltage-gated sodium channels (VGSCs) are fundamental to the initiation and propagation of action potentials in excitable cells. Ca2+/calmodulin (CaM) binds to VGSC type II (NaV1.2) isoleucine and glutamine (IQ) motif. An autism-associated mutation in NaV1.2 IQ motif, Arg1902Cys (R1902C), has been reported to affect the combination between CaM and the IQ motif compared to that of the wild type IQ motif. However, the detailed properties for the Ca2+-regulated binding of CaM to NaV1.2 IQ (1901Lys-1927Lys, IQwt) and mutant IQ motif (IQR1902C) remains unclear. Here, the binding ability of CaM and CaM's constituent proteins including N- and C lobe to the IQ motif of NaV1.2 and its mutant was investigated by protein pull-down experiments. We discovered that the combination between CaM and the IQ motif was U-shaped with the highest at [Ca2+] ≈ free and the lowest at 100 nM [Ca2+]. In the IQR1902C mutant, Ca2+-dependence of CaM binding was nearly lost. Consequently, the binding of CaM to IQR1902C at 100 and 500 nM [Ca2+] was increased compared to that of IQwt. Both N- and C lobe of CaM could bind with NaV1.2 IQ motif and IQR1902C mutant, with the major effect of C lobe. Furthermore, CaMKII had no impact on the binding between CaM and NaV1.2 IQ motif. This research offers novel insight to the regulation of NaV1.2 IQwt and IQR1902C motif, an autism-associated mutation, by CaM.


Asunto(s)
Calmodulina/metabolismo , Canal de Sodio Activado por Voltaje NAV1.2/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Trastorno Autístico/genética , Calmodulina/química , Humanos , Simulación del Acoplamiento Molecular , Mutación , Canal de Sodio Activado por Voltaje NAV1.2/química , Canal de Sodio Activado por Voltaje NAV1.2/genética , Unión Proteica
16.
Nano Lett ; 20(4): 2784-2790, 2020 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-32097017

RESUMEN

Integrating fluorescent nanoparticles with high-Q, small mode volume cavities is indispensable for nanophotonics and quantum technologies. To date, nanoparticles have largely been coupled to evanescent fields of cavity modes, which limits the strength of the interaction. Here, we developed both a cavity design and a fabrication method that enable efficient coupling between a fluorescent nanoparticle and a cavity optical mode. The design consists of a fishbone-shaped, one-dimensional photonic crystal cavity with a nanopocket located at the electric field maximum of the fundamental optical mode. Furthermore, the presence of a nanoparticle inside the pocket reduces the mode volume substantially and induces subwavelength light confinement. Our approach opens exciting pathways to achieve tight light confinement around fluorescent nanoparticles for applications in energy, sensing, lasing, and quantum technologies.

17.
Anal Chem ; 92(22): 15007-15016, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-33135876

RESUMEN

This work introduces new methods to characterize dispersions of small-diameter or low-mass-fraction nanoparticles (NPs) by single-particle inductively coupled plasma-mass spectrometry (SP ICP-MS). The optimization of ion extraction, ion transport, and the operation of the quadrupole with increased mass bandwidth improved the signal-to-noise ratios significantly and decreased the size detection limits for all NP dispersions investigated. As a model system, 10.9 ± 1.0 nm Au NPs were analyzed to demonstrate the effects of increasing ion transmission. Specifically, increasing the mass bandwidth of the quadrupole improved the size detection limit to 4.2 nm and enabled the resolution of NP signals from ionic background and noise. Subsequently, the methods were applied to the characterization of lanthanide-doped upconversion nanoparticles (UCNPs) by SP ICP-MS. Three different types of UCNPs (90 nm NaYF4: 20% Yb, 2% Er; 20 nm NaGdF4: 20% Yb, 1% Er; 15 nm NaYF4: 20% Yb, 2% Er) were investigated. Y showed the best signal-to-noise ratios with optimized ion extraction and transport parameters only, whereas the signal-to-noise ratios of Gd, Er, and Yb were further improved by increasing the mass bandwidth of a quadrupole mass filter. The novel methods were suitable for detailed characterization of diluted UCNP dispersions including particle stoichiometries and size distributions. A Poisson model was further applied to assess particle-particle interactions in the aqueous dispersions. The methods have considerable potential for the characterization of small-diameter and/or low-mass-fraction nanoparticles.

18.
Immunol Cell Biol ; 98(7): 595-606, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32339310

RESUMEN

Ficolins are important and widely distributed pattern recognition molecules that can induce lectin complement pathway activation and initiate the innate immune response. Although ficolins can bind lipopolysaccharide (LPS) in vitro, the sources, dynamic changes and roles of local ficolins in LPS-induced pulmonary inflammation and injury remain poorly understood. In this study, we established a ficolin knockout mouse model by clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) technology, and used flow cytometry and hematoxylin and eosin staining to study the expressions and roles of local ficolins in LPS-induced pulmonary inflammation and injury. Our results show that besides ficolin B (FcnB), ficolin A (FcnA) is also expressed in leukocytes from the bone marrow, peripheral blood, lung and spleen. Further analyses showed that macrophages and neutrophils are the main sources of FcnA and FcnB, and T and B cells also express a small amount of FcnB. The intranasal administration of LPS induced local pulmonary inflammation with the increased recruitment of macrophages and neutrophils. LPS stimulation induced increased expression of FcnA and FcnB in neutrophils at the acute stage and in macrophages at the late stage. The severity of the lung injury and local inflammation of Fcna-/- mice was increased by the induction of extracellular complement activation. The recovery of LPS-induced local lung inflammation and injury was delayed in Fcnb-/- mice. Hence, these findings suggested that the local macrophage- and neutrophil-derived FcnA protects against LPS-induced acute lung injury by mediating extracellular complement activation.


Asunto(s)
Lesión Pulmonar Aguda , Proteínas del Sistema Complemento/inmunología , Lectinas/inmunología , Macrófagos/inmunología , Neutrófilos/inmunología , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/inmunología , Animales , Lipopolisacáridos , Ratones , Ratones Noqueados , Ficolinas
19.
Small ; 16(6): e1905572, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31943732

RESUMEN

Cancer spheroids have structural, functional, and physiological similarities to the tumor, and have become a low-cost in vitro model to study the physiological responses of single cells and therapeutic efficacy of drugs. However, the tiny spheroid, made of a cluster of high-density cells, is highly scattering and absorptive, which prevents light microscopy techniques to reach the depth inside spheroids with high resolution. Here, a method is reported for super-resolution mapping of single nanoparticles inside a spheroid. It first takes advantage of the self-healing property of a "nondiffractive" doughnut-shaped Bessel beam from a 980 nm diode laser as the excitation, and further employs the nonlinear response of the 800 nm emission from upconversion nanoparticles, so that both excitation and emission at the near-infrared can experience minimal loss through the spheroid. These strategies lead to the development of a new nanoscopy modality with a resolution of 37 nm, 1/26th of the excitation wavelength. This method enables mapping of single nanoparticles located 55 µm inside a spheroid, with a resolution of 98 nm. It suggests a solution to track single nanoparticles and monitor their release of drugs in 3D multicellar environments.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Microscopía , Nanopartículas/análisis , Nanopartículas/química , Neoplasias/diagnóstico por imagen , Esferoides Celulares
20.
Nucleic Acids Res ; 46(5): 2459-2478, 2018 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-29361176

RESUMEN

FK506 binding proteins (FKBPs) catalyze the interconversion of cis-trans proline conformers in proteins. Importantly, FK506 drugs have anti-cancer and neuroprotective properties, but the effectors and mechanisms underpinning these properties are not well understood because the cellular function(s) of most FKBP proteins are unclear. FKBP25 is a nuclear prolyl isomerase that interacts directly with nucleic acids and is associated with several DNA/RNA binding proteins. Here, we show the catalytic FKBP domain binds microtubules (MTs) directly to promote their polymerization and stabilize the MT network. Furthermore, FKBP25 associates with the mitotic spindle and regulates entry into mitosis. This interaction is important for mitotic spindle dynamics, as we observe increased chromosome instability in FKBP25 knockdown cells. Finally, we provide evidence that FKBP25 association with chromatin is cell-cycle regulated by Protein Kinase C phosphorylation. This disrupts FKBP25-DNA contacts during mitosis while maintaining its interaction with the spindle apparatus. Collectively, these data support a model where FKBP25 association with chromatin and MTs is carefully choreographed to ensure faithful genome duplication. Additionally, they highlight that FKBP25 is a MT-associated FK506 receptor and potential therapeutic target in MT-associated diseases.


Asunto(s)
Ciclo Celular , Microtúbulos/metabolismo , Isomerasa de Peptidilprolil/metabolismo , Proteínas de Unión a Tacrolimus/metabolismo , Línea Celular , ADN/metabolismo , Inestabilidad Genómica , Humanos , Mitosis , Isomerasa de Peptidilprolil/fisiología , Fosforilación , Polimerizacion , Proteína Quinasa C/metabolismo , Proteínas de Unión a Tacrolimus/fisiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA