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1.
Proc Natl Acad Sci U S A ; 120(3): e2216672120, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36630451

RESUMEN

Cost-effective fabrication of mechanically flexible low-power electronics is important for emerging applications including wearable electronics, artificial intelligence, and the Internet of Things. Here, solution-processed source-gated transistors (SGTs) with an unprecedented intrinsic gain of ~2,000, low saturation voltage of +0.8 ± 0.1 V, and a ~25.6 µW power consumption are realized using an indium oxide In2O3/In2O3:polyethylenimine (PEI) blend homojunction with Au contacts on Si/SiO2. Kelvin probe force microscopy confirms source-controlled operation of the SGT and reveals that PEI doping leads to more effective depletion of the reverse-biased Schottky contact source region. Furthermore, using a fluoride-doped AlOx gate dielectric, rigid (on a Si substrate) and flexible (on a polyimide substrate) SGTs were fabricated. These devices exhibit a low driving voltage of +2 V and power consumption of ~11.5 µW, yielding inverters with an outstanding voltage gain of >5,000. Furthermore, electrooculographic (EOG) signal monitoring can now be demonstrated using an SGT inverter, where a ~1.0 mV EOG signal is amplified to over 300 mV, indicating significant potential for applications in wearable medical sensing and human-computer interfacing.


Asunto(s)
Inteligencia Artificial , Conducción de Automóvil , Humanos , Dióxido de Silicio , Suministros de Energía Eléctrica , Óxidos , Polietileneimina
2.
Anal Chem ; 96(24): 10013-10020, 2024 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-38836548

RESUMEN

Traditional methods for the detection of pathogenic bacteria are time-consuming, less efficient, and sensitive, which affects infection control and bungles illness. Therefore, developing a method to remedy these problems is very important in the clinic to diagnose the pathogenic diseases and guide the rational use of antibiotics. Here, microfluidic electrochemical integrated sensor (MEIS) has been investigated, functionally for rapid, efficient separation and sensitive detection of pathogenic bacteria. Three-dimensional macroporous PDMS and Au nanotube-based electrode are successfully assembled into the modeling microchip, playing the functions of "3D chaotic flow separator" and "electrochemical detector," respectively. The 3D chaotic flow separator enhances the turbulence of the fluid, achieving an excellent bacteria capture efficiency. Meanwhile, the electrochemical detector provides a quantitative signal through enzyme-linked immunoelectrochemistry with improved sensitivity. The microfluidic electrochemical integrated sensor could successfully isolate Candida albicans (C. albicans) in the range of 30-3,000,000 CFU in the saliva matrix with over 95% capture efficiency and sensitively detect C. albicans in 1 h in oral saliva samples. The integrated device demonstrates great potential in the diagnosis of oral candidiasis and is also applicable in the detection of other pathogenic bacteria.


Asunto(s)
Candida albicans , Técnicas Electroquímicas , Candida albicans/aislamiento & purificación , Técnicas Electroquímicas/instrumentación , Técnicas Analíticas Microfluídicas/instrumentación , Saliva/microbiología , Saliva/química , Electrodos , Humanos , Oro/química
3.
Small ; 20(9): e2304534, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37849036

RESUMEN

The receptor binding domain (RBD) of the SARS-CoV-2 Spike (S) glycoprotein is an appealing immunogen, but associated vaccine approaches must overcome the hapten-like nature of the compact protein and adapt to emerging variants with evolving RBD sequences. Here, a vaccine manufacturing methodology is proposed comprising a sterile-filtered freeze-dried lipid cake formulation that can be reconstituted with liquid proteins to instantaneously form liposome-displayed protein nanoparticles. Mannitol is used as a bulking agent and a small amount of Tween-80 surfactant is required to achieve reconstituted submicron particles that do not precipitate prior to usage. The lipid particles include an E. coli-derived monophosphoryl lipid A (EcML) for immunogenicity, and cobalt porphyrin-phospholipid (CoPoP) for antigen display. Reconstitution of the lipid cake with aqueous protein results in rapid conversion of the RBD into intact liposome-bound format prior to injection. Protein particles can readily be formed with sequent-divergent RBD proteins derived from the ancestral or Omicron strains. Immunization of mice elicits antibodies that neutralize respective viral strains. When K18-hACE2 transgenic mice are immunized and challenged with ancestral SARS-CoV-2 or the Omicron BA.5 variant, both liquid liposomes displaying the RBD and rapid reconstituted particles protect mice from infection, as measured by the viral load in the lungs and nasal turbinates.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Animales , Ratones , Nanovacunas , SARS-CoV-2 , Escherichia coli , Liposomas , COVID-19/prevención & control , Lípidos
4.
Calcif Tissue Int ; 114(3): 237-245, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38051322

RESUMEN

This study aimed to examine the association between sex hormone-binding globulin (SHBG) and osteoporosis through a cross-sectional study and a two-sample bidirectional Mendelian randomization (MR). We used the National Health and Nutrition Examination Survey (NHANES) 2013-2014 and 2015-2016 data, with exposure as serum SHBG and outcome as osteoporosis and performed multivariate logistic regression to test the correlation between SHBG and osteoporosis. To determine the causal relationship between SHBG and osteoporosis, a two-sample bidirectional MR was employed. The genome-wide association study (GWAS) dataset for SHBG (n = 189,473) was obtained from the IEU database, and the GWAS dataset for osteoporosis (n = 212,778) was obtained from the FinnGen bioBank. The principal MR technique was inverse-variance weighting (IVW). In MR analyses, the MR-Egger intercept and Cochran Q test were used to detect multiple validity and horizontal heterogeneity. 1249 older adult participants (age ≥ 60) were involved in the cross-sectional study, including 113 osteoporosis cases. We identified a significant relationship between circulating SHBG concentration and osteoporosis risk [OR 3.963, 95% CI (2.095-7.495), P < 0.05]. Subgroup analysis indicated that SHBG was closely linked to the risk of osteoporosis in the female population [OR 1.008, 95% CI (1.002-1.013), P = 0.005] but not in males (P = 0.065). In addition, The IVW approach suggested a causal connection between SHBG and increased osteoporosis risk [OR 1.479, 95% CI (1.144-1.912), P = 0.003], and the MR-Egger intercept and the Cochran Q test validated the consistency of the MR results. Finally, the reverse MR analysis declined to identify a causal relation between SHBG and osteoporosis. Our research demonstrates a significant causal connection between circulating SHBG levels and increased osteoporosis risk. These results indicate that high SHBG may be associated with the risk of osteoporosis in postmenopausal women, but more research is needed.


Asunto(s)
Osteoporosis , Globulina de Unión a Hormona Sexual , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Transversales , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Nonoxinol , Encuestas Nutricionales , Osteoporosis/epidemiología , Osteoporosis/genética , Globulina de Unión a Hormona Sexual/genética
5.
Biomacromolecules ; 25(7): 4215-4232, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38845149

RESUMEN

Boron neutron capture therapy (BNCT) targets invasive, radioresistant cancers but requires a selective and high B-10 loading boron drug. This manuscript investigates boron-rich poly(ethylene glycol)-block-(poly(4-vinylphenyl boronate ester)) polymer micelles synthesized via atom transfer radical polymerization for their potential application in BNCT. Transmission electron microscopy (TEM) revealed spherical micelles with a uniform size of 43 ± 10 nm, ideal for drug delivery. Additionally, probe sonication proved effective in maintaining the micelles' size and morphology postlyophilization and reconstitution. In vitro studies with B16-F10 melanoma cells demonstrated a 38-fold increase in boron accumulation compared to the borophenylalanine drug for BNCT. In vivo studies in a B16-F10 tumor-bearing mouse model confirmed enhanced tumor selectivity and accumulation, with a tumor-to-blood (T/B) ratio of 2.5, surpassing BPA's T/B ratio of 1.8. As a result, mice treated with these micelles experienced a significant delay in tumor growth, highlighting their potential for BNCT and warranting further research.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Micelas , Terapia por Captura de Neutrón de Boro/métodos , Animales , Ratones , Melanoma Experimental/patología , Melanoma Experimental/tratamiento farmacológico , Ácidos Borónicos/química , Línea Celular Tumoral , Polietilenglicoles/química , Polímeros/química , Ratones Endogámicos C57BL , Ésteres/química , Ésteres/farmacología , Compuestos de Boro/química , Compuestos de Boro/farmacología
6.
Analyst ; 149(13): 3530-3536, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38757525

RESUMEN

ATP plays a crucial role in cell energy supply, so the quantification of intracellular ATP levels is particularly important for understanding many physio-pathological processes. The intracellular quantification of this non-electroactive molecule can be realized using aptamer-modified nanoelectrodes, but is hindered by the limited quantity of modification and electroactive tags on the nanosized electrodes. Herein, we developed a simple but effective electrochemical signal amplification strategy for intracellular ATP detection, which replaces the regular ATP aptamer-linked ferrocene monomer with a polymer, thus greatly magnifying the amounts of electrochemical reporters linked to one chain of the aptamer and enhancing the signals. This ferrocene polymer-ATP aptamer was further immobilized onto Au nanowire electrodes (SiC@C@Au NWEs) to achieve accurate quantification of intracellular ATP in single cells, presenting high electrochemical signal output and high specificity. This work not only provides a powerful tool for quantifying intracellular ATP but also offers a simple and versatile strategy for electrochemical signal amplification in the detection of broader non-electroactive molecules involved in different kinds of intracellular physiological processes.


Asunto(s)
Adenosina Trifosfato , Aptámeros de Nucleótidos , Técnicas Biosensibles , Técnicas Electroquímicas , Compuestos Ferrosos , Oro , Metalocenos , Adenosina Trifosfato/análisis , Aptámeros de Nucleótidos/química , Humanos , Oro/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Metalocenos/química , Compuestos Ferrosos/química , Técnicas Biosensibles/métodos , Electrodos , Polímeros/química , Nanocables/química , Límite de Detección , Células HeLa
7.
J Invertebr Pathol ; 206: 108167, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39033903

RESUMEN

Honey bees utilize queen mandibular pheromone (QMP) for maintaining social hierarchy and colony development. In controlled cage studies, synthetic QMP is often introduced to mimic natural conditions. However, questions have arisen about the effects of QMP on nosema disease studies. This short report identifies significant early-stage suppression effects of QMP on Nosema (Vairimorpha) ceranae infections. QMP was found to significantly lower infection rates below the reported infectious dose for 50 % infectivity (ID50) and to slow disease development in a dose-independent manner. These effects diminished at doses exceeding ID100. We recommend that studies investigating treatment effects using caged bees avoid QMP to ensure unambiguous results. Additionally, employing multiple infectious doses with shorter incubation times would be useful for evaluating other treatments that may have subtle effects. Furthermore, our findings support previous field studies suggesting that queen replacement reduces nosema disease at levels similar to treatment with fumagillin.

8.
Proc Natl Acad Sci U S A ; 118(22)2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34050027

RESUMEN

Recombinant influenza virus vaccines based on hemagglutinin (HA) hold the potential to accelerate production timelines and improve efficacy relative to traditional egg-based platforms. Here, we assess a vaccine adjuvant system comprised of immunogenic liposomes that spontaneously convert soluble antigens into a particle format, displayed on the bilayer surface. When trimeric H3 HA was presented on liposomes, antigen delivery to macrophages was improved in vitro, and strong functional antibody responses were induced following intramuscular immunization of mice. Protection was conferred against challenge with a heterologous strain of H3N2 virus, and naive mice were also protected following passive serum transfer. When admixed with the particle-forming liposomes, immunization reduced viral infection severity at vaccine doses as low as 2 ng HA, highlighting dose-sparing potential. In ferrets, immunization induced neutralizing antibodies that reduced the upper respiratory viral load upon challenge with a more modern, heterologous H3N2 viral strain. To demonstrate the flexibility and modular nature of the liposome system, 10 recombinant surface antigens representing distinct influenza virus strains were bound simultaneously to generate a highly multivalent protein particle that with 5 ng individual antigen dosing induced antibodies in mice that specifically recognized the constituent immunogens and conferred protection against heterologous H5N1 influenza virus challenge. Taken together, these results show that stable presentation of recombinant HA on immunogenic liposome surfaces in an arrayed fashion enhances functional immune responses and warrants further attention for the development of broadly protective influenza virus vaccines.


Asunto(s)
Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Subtipo H3N2 del Virus de la Influenza A/inmunología , Subtipo H5N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Liposomas , Adyuvantes Inmunológicos/administración & dosificación , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , Relación Dosis-Respuesta Inmunológica , Hurones , Ratones
9.
Plant Dis ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143816

RESUMEN

Heliconia subulata is a common ornamental plant, it has been widely planted in southern China for greening parks, roads, and residential areas. H. subulata plants with spots on their leaves were observed in East Coast Wetland Park (18°16'53.37″N, 109°30'19.36″E), Sanya City, Hainan Province, China on Aug. 31, 2023. The symptoms of the leaves are irregular gray-white, spots, that develop into brown and black, with yellow halos at the disease-health junction. Following an on-the-spot investigation, it was found that the incidence of the disease was 40 to 50%. The leaves were disinfected with 70% ethanol for 1 min, rinsed with sterile water 3 times, disinfected for 1 min with 0.1% HgCl2, rinsed with sterile water 3 times, dried, put on potato dextrose agar (PDA) and incubated at 28℃ for 7 days. The red conidia pile was selected from the culture, dispersed in sterile water and diluted to 20 µL containing 1 to 2 conidia. After absorbing 20 µL spore suspension for many times and inoculating it on the new PDA plate, five pure cultures of single spore, J-1-1 to J-1-5, were obtained. After 7 days of growth, the colonies were grayish aerial mycelium on the front and light orange conidia on the reverse. The white aerial mycelia, conidia, acervulus, and appressorium were observed (Supplementary Fig. S1). The morphological characteristics showed that the isolate had the same characteristics as the previously described Colletotrichum spp. (Wang et al. 2021). The genomic DNA of isolates J-1-1 and J-1-5 were extracted by Fungal DNA Kit (OMEGA bio-tek, Guangzhou, China). The internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GADPH), and ß-tubulin 2 genes (TUB2) were amplified by primers ITS1/ITS4, GDF/GDR, and Bt2a/Bt2b, respectively (Weir et al. 2012). Based on sequencing and gene sequence alignment analysis, it was found that the consistency between the ITS sequences of isolates J-1-1 and J-1-5 was 99.82%. The consistency between GADPH and TUB2 sequences was 100%. The gene sequences of isolates J-1-1 and J-1-5 were submitted to GenBank with accession numbers PP455510/PP455511 (ITS), PP510210/PP510211 (GADPH) and PP510212/PP510213 (TUB2) respectively. Based on the BLAST analysis, the three sequences were more than 99% identical to those of the C. tropicale strain FC1 (ITS: MT192648, GAPDH: MT155819, TUB2: MT199874; Duan et al. 2022). A phylogenetic tree was constructed by MEGA 11 based on the ITS, GADPH, and TUB2 gene sequence by the maximum-likelihood method. The results showed that the isolates J-1-1 and J-1-5 were clustered with C. tropicale CBS:124949 (Supplementary Fig. S2). Based on morphological and molecular biological analysis, two isolates were identified as C. tropicale. To further test the pathogenicity of isolates J-1-1 and J-1-5, spore suspensions (1×106 conidia/mL) were prepared and 20 µL spore suspensions were inoculated on the leaves of healthy H. subulata potted plants stabbed with sterile toothpicks. Three leaves were inoculated in each treatment, and sterile water was inoculated as a control. The treated plants were placed in an incubator with a temperature of 28℃, relative humidity of 90%, and light/dark (12h/12h). After 15 days, the spore suspension treatment showed the same symptoms as the naturally diseased H. subulata plants in the field, but the leaves treated with sterile water were not infected (Supplementary Fig. S1). The morphology of the isolates obtained from diseased leaves was the same as that of isolates J-1-1 and J-1-5 on the PDA plate. To our knowledge, this is the first report of H. subulata, a new host of C. tropicale causing anthracnose in China.

10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(2): 368-375, 2024 Apr 25.
Artículo en Zh | MEDLINE | ID: mdl-38686419

RESUMEN

The freeze-drying is a technology that preserves biological samples in a dry state, which is beneficial for storage, transportation, and cost saving. In this study, the bovine pericardium was treated with a freeze-drying protectant composed of polyethylene glycol (PEG) and trehalose (Tre), and then freeze-dried. The results demonstrated that the mechanical properties of the pericardium treated with PEG + 10% w/v Tre were superior to those of the pericardium fixed with glutaraldehyde (GA). The wet state water content of the rehydrated pericardium, determined using the Karl Fischer method, was (74.81 ± 1.44)%, which was comparable to that of the GA-fixed pericardium. The dry state water content was significantly reduced to (8.64 ± 1.52)%, indicating effective dehydration during the freeze-drying process. Differential scanning calorimetry (DSC) testing revealed that the thermal shrinkage temperature of the pericardium was (84.96 ± 0.49) ℃, higher than that of the GA-fixed pericardium (83.14 ± 0.11) ℃, indicating greater thermal stability. Fourier transform infrared spectroscopy (FTIR) results showed no damage to the protein structure during freeze-drying. Hematoxylin and eosin (HE) staining demonstrated that the freeze-drying process reduced pore formation, prevented ice crystal growth, and resulted in a tighter arrangement of tissue fibers. The frozen-dried bovine pericardium was subjected to tests for cell viability and hemolysis rate. The results revealed a cell proliferation rate of (77.87 ± 0.49)%, corresponding to a toxicity grade of 1. Additionally, the hemolysis rate was (0.17 ± 0.02)%, which is below the standard of 5%. These findings indicated that the frozen-dried bovine pericardium exhibited satisfactory performance in terms of cytotoxicity and hemolysis, thus meeting the relevant standards. In summary, the performance of the bovine pericardium treated with PEG + 10% w/v Tre and subjected to freeze-drying could meet the required standards.


Asunto(s)
Liofilización , Pericardio , Polietilenglicoles , Trehalosa , Animales , Pericardio/química , Trehalosa/química , Trehalosa/farmacología , Bovinos , Polietilenglicoles/química , Glutaral/química , Rastreo Diferencial de Calorimetría
11.
Angew Chem Int Ed Engl ; 63(30): e202403241, 2024 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-38710651

RESUMEN

Exocytosis involving the fusion of intracellular vesicles with cell membrane, is thought to be modulated by the mechanical cues in the microenvironment. Single-cell electrochemistry can offer unique information about the quantification and kinetics of exocytotic events; however, the effects of mechanical force on vesicular release have been poorly explored. Herein, we developed a stretchable microelectrode with excellent electrochemical stability under mechanical deformation by microfabrication of functionalized poly(3,4-ethylenedioxythiophene) conductive ink, which achieved real-time quantitation of strain-induced vesicular exocytosis from a single cell for the first time. We found that mechanical strain could cause calcium influx via the activation of Piezo1 channels in chromaffin cell, initiating the vesicular exocytosis process. Interestingly, mechanical strain increases the amount of catecholamines released by accelerating the opening and prolonging the closing of fusion pore during exocytosis. This work is expected to provide revealing insights into the regulatory effects of mechanical stimuli on vesicular exocytosis.


Asunto(s)
Células Cromafines , Exocitosis , Células Cromafines/metabolismo , Microelectrodos , Animales , Microtecnología/métodos , Calcio/metabolismo , Estrés Mecánico , Polímeros/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química
12.
Small ; 19(21): e2208241, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36843317

RESUMEN

Platinum (Pt) drugs are widely used in clinic for cancer therapy, but their therapeutic outcomes are significantly compromised by severe side effects and acquired drug resistance. With the emerging immunotherapy and imaging-guided cancer therapy, precise delivery and release of Pt drugs have drawn great attention these days. The targeting delivery of Pt drugs can greatly increase the accumulation at tumor sites, which ultimately enhances antitumor efficacy. Further, with the combination of Pt drugs and other theranostic agents into one nanosystem, it not only possesses excellent synergistic efficacy but also achieves real-time monitoring. In this review, after the introduction of Pt drugs and their characteristics, the recent progress of polymeric nanosystems for efficient delivery of Pt drugs is summarized with an emphasis on multi-modal synergistic therapy and imaging-guided Pt-based cancer treatment. In the end, the conclusions and future perspectives of Pt-encapsulated nanosystems are given.


Asunto(s)
Antineoplásicos , Neoplasias , Profármacos , Humanos , Platino (Metal) , Sistemas de Liberación de Medicamentos , Neoplasias/tratamiento farmacológico , Profármacos/uso terapéutico , Polímeros/uso terapéutico , Antineoplásicos/uso terapéutico
13.
J Virol ; 96(19): e0100622, 2022 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-36106872

RESUMEN

Intranasal vaccination offers the potential advantage of needle-free prevention of respiratory pathogens such as influenza viruses with induction of mucosal immune responses. Optimal design of adjuvants and antigen delivery vehicles for intranasal delivery has not yet been well established. Here, we report that an adjuvant-containing nanoliposome antigen display system that converts soluble influenza hemagglutinin antigens into nanoparticles is effective for intranasal immunization. Intranasal delivery of nanoliposomes in mice delivers the particles to resident immune cells in the respiratory tract, inducing a mucosal response in the respiratory system as evidenced by nasal and lung localized IgA antibody production, while also producing systemic IgG antibodies. Intranasal vaccination with nanoliposome particles decorated with nanogram doses of hemagglutinin protected mice from homologous and heterologous H3N2 and H1N1 influenza virus challenge. IMPORTANCE A self-assembling influenza virus vaccine platform that seamlessly converts soluble antigens into nanoparticles is demonstrated with various H1N1 and H3N2 influenza antigens to protect mice against influenza virus challenge following intranasal vaccination. Mucosal immune responses following liposome delivery to lung antigen-presenting cells are demonstrated.


Asunto(s)
Glicoproteínas Hemaglutininas del Virus de la Influenza , Inmunidad Mucosa , Vacunas contra la Influenza , Infecciones por Orthomyxoviridae , Adyuvantes Inmunológicos , Administración Intranasal , Animales , Anticuerpos Antivirales/inmunología , Células Presentadoras de Antígenos/inmunología , Glicoproteínas Hemaglutininas del Virus de la Influenza/administración & dosificación , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Inmunoglobulina A/inmunología , Inmunoglobulina G/inmunología , Subtipo H1N1 del Virus de la Influenza A , Subtipo H3N2 del Virus de la Influenza A , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la Influenza/inmunología , Liposomas , Ratones , Nanopartículas , Infecciones por Orthomyxoviridae/prevención & control , Vacunación
14.
Nat Mater ; 21(5): 564-571, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35501364

RESUMEN

Realizing fully stretchable electronic materials is central to advancing new types of mechanically agile and skin-integrable optoelectronic device technologies. Here we demonstrate a materials design concept combining an organic semiconductor film with a honeycomb porous structure with biaxially prestretched platform that enables high-performance organic electrochemical transistors with a charge transport stability over 30-140% tensional strain, limited only by metal contact fatigue. The prestretched honeycomb semiconductor channel of donor-acceptor polymer poly(2,5-bis(2-octyldodecyl)-3,6-di(thiophen-2-yl)-2,5-diketo-pyrrolopyrrole-alt-2,5-bis(3-triethyleneglycoloxy-thiophen-2-yl) exhibits high ion uptake and completely stable electrochemical and mechanical properties over 1,500 redox cycles with 104 stretching cycles under 30% strain. Invariant electrocardiogram recording cycles and synapse responses under varying strains, along with mechanical finite element analysis, underscore that the present stretchable organic electrochemical transistor design strategy is suitable for diverse applications requiring stable signal output under deformation with low power dissipation and mechanical robustness.


Asunto(s)
Electrónica , Transistores Electrónicos , Polímeros/química , Semiconductores , Tiofenos/química
15.
Osteoporos Int ; 34(4): 749-762, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36738335

RESUMEN

To establish a risk prediction model for residual low back pain after percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fractures. We used retrospective data for model construction and evaluated the model using internal validation and temporal external validation and finally concluded that the model had good predictive performance. INTRODUCTION: The cause of residual low back pain in patients with osteoporotic vertebral compression fractures (OVCFs) after PKP remains highly controversial, and our goal was to investigate the most likely cause and to develop a novel nomogram for the prediction of residual low back pain and to evaluate the predictive performance of the model. METHODS: The clinical data of 281 patients with OVCFs who underwent PKP at our hospital from July 2019 to July 2020 were reviewed. The optimal logistic regression model was determined by lasso regression for multivariate analysis, thus constructing a nomogram. Bootstrap was used to perfomance the internal validation; receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to assess the predictive performance and clinical utility of the model, respectively. Temporal external validation of the model was also performed using retrospective data from 126 patients who underwent PKP at our hospital from January 2021 to October 2021. RESULTS: Lasso regression cross-validation showed that the variables with non-zero coefficients were the number of surgical vertebrae, preoperative bone mineral density (pre-BMD), smoking history, thoracolumbar fascia injury (TLFI), intraoperative facet joint injury (FJI), and postoperative incomplete cementing of the fracture line (ICFL). The above factors were included in the multivariate analysis and showed that the pre-BMD, smoking history, TLFI, FJI, and ICFL were independent risk factors for residual low back pain (P < 0.05). The ROC and calibration curve of the original model and temporal external validation indicated a good predictive power of the model. The DCA curve suggested that the model has good clinical practicability. CONCLUSION: The risk prediction model has good predictive performance and clinical practicability, which can provide a certain basis for clinical decision-making in patients with OVCFs.


Asunto(s)
Fracturas por Compresión , Cifoplastia , Dolor de la Región Lumbar , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Humanos , Cifoplastia/efectos adversos , Fracturas por Compresión/cirugía , Fracturas por Compresión/complicaciones , Estudios Retrospectivos , Dolor de la Región Lumbar/etiología , Dolor de la Región Lumbar/cirugía , Nomogramas , Fracturas de la Columna Vertebral/complicaciones , Fracturas de la Columna Vertebral/cirugía , Fracturas Osteoporóticas/cirugía , Fracturas Osteoporóticas/etiología , Vértebras Lumbares/cirugía , Vértebras Lumbares/lesiones , Resultado del Tratamiento , Cementos para Huesos
16.
Chem Biodivers ; 20(6): e202201246, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37186504

RESUMEN

Rational design of high-efficiency N-heterocyclic carbene (NHC) palladium catalyst is of great importance to modern organic synthesis, especially in chemical and pharmaceutical industries. Herein, we fabricate a polymer network containing N-heterocyclic carbene palladium (PNNHC-Pd) catalytic active sites via an immobilization process. The N-heterocyclic carbene palladium can serve as a promising linkage of polymer network as well as an effective catalytic active site owing to its structural preference and strong σ-donating ability with palladium species. The results display that N-heterocyclic carbene palladium disperses homogeneously in polymer network, thus rendering PNNHC-Pd excellent catalytic activity, high stability and superior reusability in palladium-catalyzed Suzuki-Miyaura coupling reaction in aqueous medium. This work provides a new insight into the development of heterogenization of homogeneous catalysts based on polymer network.


Asunto(s)
Paladio , Agua , Catálisis , Polímeros
17.
Sensors (Basel) ; 23(1)2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36617085

RESUMEN

Fused deposition modeling (FDM) is a form of additive manufacturing where three-dimensional (3D) models are created by depositing melted thermoplastic polymer filaments in layers. Although FDM is a mature process, defects can occur during printing. Therefore, an image-based quality inspection method for 3D-printed objects of varying geometries was developed in this study. Transfer learning with pretrained models, which were used as feature extractors, was combined with ensemble learning, and the resulting model combinations were used to inspect the quality of FDM-printed objects. Model combinations with VGG16 and VGG19 had the highest accuracy in most situations. Furthermore, the classification accuracies of these model combinations were not significantly affected by differences in color. In summary, the combination of transfer learning with ensemble learning is an effective method for inspecting the quality of 3D-printed objects. It reduces time and material wastage and improves 3D printing quality.


Asunto(s)
Plásticos , Impresión Tridimensional , Aprendizaje , Aprendizaje Automático
18.
Int J Mol Sci ; 24(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36902281

RESUMEN

Oral squamous cell carcinoma (OSCC) can arise anywhere in the oral cavity. OSCC's molecular pathogenesis is complex, resulting from a wide range of events that involve the interplay between genetic mutations and altered levels of transcripts, proteins, and metabolites. Platinum-based drugs are the first-line treatment for OSCC; however, severe side-effects and resistance are challenging issues. Thus, there is an urgent clinical need to develop novel and/or combinatory therapeutics. In this study, we investigated the cytotoxic effects of pharmacological concentrations of ascorbate on two human oral cell lines, the oral epidermoid carcinoma meng-1 (OECM-1) cell and the Smulow-Glickman (SG) human normal gingival epithelial cell. Our study examined the potential functional impact of pharmacological concentrations of ascorbates on the cell-cycle profiles, mitochondrial-membrane potential, oxidative response, the synergistic effect of cisplatin, and the differential responsiveness between OECM-1 and SG cells. Two forms of ascorbate, free and sodium forms, were applied to examine the cytotoxic effect and it was found that both forms had a similar higher sensitivity to OECM-1 cells than to SG cells. In addition, our study data suggest that the determinant factor of cell density is important for ascorbate-induced cytotoxicity in OECM-1 and SG cells. Our findings further revealed that the cytotoxic effect might be mediated through the induction of mitochondrial reactive oxygen species (ROS) generation and the reduction in cytosolic ROS generation. The combination index supported the agonistic effect between sodium ascorbate and cisplatin in OECM-1 cells, but not in SG cells. In summary, our current findings provide supporting evidence for ascorbate to serve as a sensitizer for platinum-based treatment of OSCC. Hence, our work provides not only repurposing of the drug, ascorbate, but also an opportunity to decrease the side-effects of, and risk of resistance to, platinum-based treatment for OSCC.


Asunto(s)
Antineoplásicos , Carcinoma de Células Escamosas , Neoplasias de la Boca , Humanos , Cisplatino/farmacología , Especies Reactivas de Oxígeno/metabolismo , Carcinoma de Células Escamosas/patología , Ácido Ascórbico/farmacología , Neoplasias de la Boca/patología , Antineoplásicos/farmacología , Estrés Oxidativo , Línea Celular Tumoral , Apoptosis
19.
Molecules ; 28(5)2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36903458

RESUMEN

Hepatocellular carcinoma (HCC) is the fourth most common cause of cancer-related deaths in the world. However, there are currently few clinical diagnosis and treatment options available, and there is an urgent need for novel effective approaches. More research is being undertaken on immune-associated cells in the microenvironment because they play a critical role in the initiation and development of HCC. Macrophages are specialized phagocytes and antigen-presenting cells (APCs) that not only directly phagocytose and eliminate tumor cells, but also present tumor-specific antigens to T cells and initiate anticancer adaptive immunity. However, the more abundant M2-phenotype tumor-associated macrophages (TAMs) at tumor sites promote tumor evasion of immune surveillance, accelerate tumor progression, and suppress tumor-specific T-cell immune responses. Despite the great success in modulating macrophages, there are still many challenges and obstacles. Biomaterials not only target macrophages, but also modulate macrophages to enhance tumor treatment. This review systematically summarizes the regulation of tumor-associated macrophages by biomaterials, which has implications for the immunotherapy of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Macrófagos Asociados a Tumores , Materiales Biocompatibles , Macrófagos , Microambiente Tumoral
20.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(5): 899-909, 2023 Oct 18.
Artículo en Zh | MEDLINE | ID: mdl-37807746

RESUMEN

OBJECTIVE: To compare and analyze the feasibility of autologous facet joint bone block as an alternative to polyetheretherketone (PEEK) cage in lumbar intervertebral fusion surgery for patients with osteoporosis. METHODS: From December 2018 to June 2021, the case data of patients with osteoporosis (T value ≤ -2.5 on dual energy X-ray bone density) who underwent posterior lumbar interbody fusion in the Fourth Medical Center, Chinese PLA General Hospital were retrospectively reviewed. All the cases were followed up for no less than 12 months and were divided into two groups according to the differences of interbody fusion materials: the autologous facet joint bone block group (autogenous bone group) and the PEEK cage group (PEEK group). The general data [such as age, gender, body mass index (BMI), primary diagnosis, distribution of fusion segments, bone mineral density of lumbar (BMD), incidence of preoperative complications], the perioperative data (such as duration of operation, intraoperative blood loss, postoperative drainage, perioperative allogeneic blood transfusion rate), and the incidence of postoperative complications were compared between the two groups. Imaging parameters (disc height, lumbar lordosis angle, segment lordosis angle, segmental lordosis angle, disc height improvement rate, and fusion rate) and lumbar functional scores [visual analogue scale (VAS), Oswestry disability index (ODI), Japanese Orthopedics Association (JOA) score for lower back pain] were compared to evaluate the clinical efficacy between the kinds of intervertebral fusion materials 1 week, 3 months and 6 months postoperative and at the last follow-up. RESULTS: A total of 118 patients were enrolled, including 68 cases in the autogenous bone group and 50 cases in the PEEK group, there were no statistical differences in age, gender, BMI, primary diagnosis, distribution of fusion segments, BMD, incidence of preoperative complications, duration of operation, intraoperative blood loss, postoperative drainage, perioperative allogeneic blood transfusion rate, incidence of postoperative complications, all the preoperative imaging parameters and all the lumbar function scores between the two groups (P>0.05). Postoperative superficial surgical site infections occurred in 3 patients in the autogenous bone group and 2 patients in the PEEK group. At the last follow-up, 3 cases of intervertebral graft collapse occurred in the autogenous bone group and 5 cases in the PEEK group, 1 case of graft subsidence in the autogenous bone group and 1 case in the PEEK group. All the imaging parameters showed significant differences between postoperation and preoperation (P < 0.05), and all the imaging parameters showed significant differences between 1 week and 3 months postoperative in both groups (P < 0.05). The height, angle of fusion gap in the autogenous bone group were lower than those in the PEEK group 1 week postoperatively (P < 0.05), and the fusion gap height improvement rate in the autogenous bone group was lower than that in the PEEK group (P < 0.05). The cases in both groups started to show final fusion 3 months after surgery, and the fusion rate in the autogenous bone group was 75% 6 months postoperatively, which was significantly higher than the rate of 56% in the PEEK group (P < 0.05), and there was no statistically significant difference in the final fusion rate between the two groups (P>0.05). The ODI, the postoperative VAS score was significantly lower than that in preoperation, while the postoperative JOA score was significantly higher than that in preoperation (P < 0.05). The ODI was lower while the JOA score was higher of the autogenous bone group than that of the PEEK group 6 months postoperatively (P < 0.05). CONCLUSION: In osteoporosis patients, good interbody fusion rate and improvement of lumbar vertebral function can be obtained by using autologous facet joint bone block or PEEK cage, while the fusion rate and the improvement of lumbar function with autologous facet joint bone block are better than those with PEEK cage 6 months post-operatively. PEEK cage is superior to autologous facet joint bone block in intervertebral distraction and improvement of lumbar lordosis. Significant disc space subsidence occurred in osteoporotic patients within 3 months after lumbar interbody fusion, and the subsidence of PEEK cage was more obvious than that of autologous facet joint bone block.


Asunto(s)
Lordosis , Osteoporosis , Fusión Vertebral , Articulación Cigapofisaria , Humanos , Estudios Retrospectivos , Fusión Vertebral/métodos , Polietilenglicoles/uso terapéutico , Resultado del Tratamiento , Cetonas , Vértebras Lumbares/cirugía , Pérdida de Sangre Quirúrgica , Complicaciones Posoperatorias , Hemorragia Posoperatoria
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