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An optical fiber interferometer coated with PbS quantum dots (QDs) was developed for copper ion (${{\rm{Cu}}^{2 +}}$) detection. The QDs were modified by a multifunctional copolymer that enabled QD surface ligation, dispersion, and coordination with ${{\rm{Cu}}^{2 +}}$. ${{\rm{Cu}}^{2 +}}$ coordination with the polymer induced changes in the surrounding refractive index of the interferometer. The sensor was highly selective for ${{\rm{Cu}}^{2 +}}$ and showed a linear detection range of 0-1000 µM with a limit of detection of 2.20 µM in both aqueous and biological solutions.
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Técnicas Biosensibles/instrumentación , Cobre/análisis , Interferometría/instrumentación , Plomo/química , Polímeros/química , Puntos Cuánticos , Sulfuros/química , Diseño de EquipoRESUMEN
Aqueous rechargeable Zn-metal batteries (ARZBs) are considered one of the most promising candidates for grid-scale energy storage. However, their widespread commercial application is largely plagued by three major challenges: The uncontrollable Zn dendrites, notorious parasitic side reactions, and sluggish Zn2+ ion transfer. To address these issues, we design a sustainable dual cross-linked cellulose hydrogel electrolyte, which has excellent mechanical strength to inhibit dendrite formation, high Zn2+ ions binding capacity to suppress side reaction, and abundant porous structure to facilitate Zn2+ ions migration. Consequently, the Zn||Zn cell with the hydrogel electrolyte can cycle stably for more than 400 h under a high current density of 10 mA cm-2. Moreover, the hydrogel electrolyte also enables the Zn||polyaniline cell to achieve high-rate and long-term cycling performance (> 2000 cycles at 2000 mA g-1). Remarkably, the hydrogel electrolyte is easily accessible and biodegradable, making the ARZBs attractive in terms of scalability and sustainability.
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Percutaneous renal biopsy is commonly used for kidney cancer diagnosis. However, the biopsy procedure remains challenging in sampling accuracy. Here we introduce a forward-viewing optical coherence tomography probe for differentiating tumor and normal tissues, aiming at precise biopsy guidance. Totally, ten human kidney samples, nine of which had malignant renal carcinoma and one had benign oncocytoma, were used for system evaluation. Based on their distinct imaging features, carcinoma could be efficiently distinguished from normal renal tissues. Additionally, oncocytoma could be differentiated from carcinoma. We developed convolutional neural networks for tissue recognition. Compared to the conventional attenuation coefficient method, convolutional neural network models provided more accurate carcinoma predictions. These models reached a tissue recognition accuracy of 99.1% on a hold-out set of four kidney samples. Furthermore, they could efficiently distinguish oncocytoma from carcinoma. In conclusion, our convolutional neural network-aided endoscopic imaging platform could enhance carcinoma diagnosis during percutaneous renal biopsy procedures.
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The in vivo three-dimensional genomic architecture of adult mature neurons at homeostasis and after medically relevant perturbations such as axonal injury remains elusive. Here we address this knowledge gap by mapping the three-dimensional chromatin architecture and gene expression programme at homeostasis and after sciatic nerve injury in wild-type and cohesin-deficient mouse sensory dorsal root ganglia neurons via combinatorial Hi-C and RNA-seq. We find that cohesin is required for the full induction of the regenerative transcriptional program, by organising 3D genomic domains required for the activation of regenerative genes. Importantly, loss of cohesin results in disruption of chromatin architecture at regenerative genes and severely impaired nerve regeneration. Together, these data provide an original three-dimensional chromatin map of adult sensory neurons in vivo and demonstrate a role for cohesin-dependent chromatin interactions in neuronal regeneration.
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Percutaneous renal biopsy (PRB) is commonly used for kidney cancer diagnosis. However, current PRB remains challenging in sampling accuracy. This study introduces a forward-viewing optical coherence tomography (OCT) probe for differentiating tumor and normal tissues, aiming at precise PRB guidance. Five human kidneys and renal carcinoma samples were used to evaluate the performance of our probe. Based on their distinct OCT imaging features, tumor and normal renal tissues can be accurately distinguished. We examined the attenuation coefficient for tissue classification and achieved 98.19% tumor recognition accuracy, but underperformed for distinguishing normal tissues. We further developed convolutional neural networks (CNN) and evaluated two CNN architectures: ResNet50 and InceptionV3, yielding 99.51% and 99.48% accuracies for tumor recognition, and over 98.90% for normal tissues recognition. In conclusion, combining OCT and CNN significantly enhanced the PRB guidance, offering a promising guidance technology for improved kidney cancer diagnosis.
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OBJECTIVE: Multicellular tumor spheroids (MCTs) are indispensable models for evaluating drug efficacy for precision cancer therapeutic strategies as well as for repurposing FDA-approved drugs for ovarian cancer. However, current imaging techniques cannot provide effective monitoring of pathological responses due to shallow penetration and experimentally operative destruction. We plan to utilize a noninvasive optical imaging tool to achieve in vivo longitudinal monitoring of the growth of MCTs and therapeutic responses to repurpose three FDA-approved drugs for ovarian cancer therapy. METHODS: A swept-source optical coherence tomography (SS-OCT) system was used to monitor the volume growth of MCTs over 11 days. Three inhibitors of 2-Methoxyestradiol (2-ME), AZD1208, and R-Ketorolac (R-keto) with concentrations of 1, 10, and 25 µM were employed to treat ovarian MCTs on day 5. Three-dimensional (3D), intrinsic optical attenuation contrast, and degree of uniformity were applied to analyze the therapeutic effect of these inhibitors on ovarian MCTs. RESULTS: We found that 2-ME, AZD1208, and R-keto with concentration of 10 and 25 µM significantly inhibited the volume growth of ovarian MCTs. There was no effect to necrotic tissues from all concentrations of 2-ME, AZD1208, and R-keto inhibitors from our OCT results. 2-ME and AZD1208 inhibited the growth of high uniformity tissues within MCTs and higher concentrations provided more significant inhibitory effects. CONCLUSION: Our results indicated that OCT was capable and reliable to monitor the therapeutic effect of inhibitors to ovarian MCTs and it can be used for the rapid characterization of novel therapeutics for ovarian cancers in the future.
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Reposicionamiento de Medicamentos , Neoplasias Ováricas , Humanos , Femenino , Tomografía de Coherencia Óptica/métodos , Mercaptoetanol/uso terapéutico , Neoplasias Ováricas/diagnóstico por imagen , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patologíaRESUMEN
Nerve injuries cause permanent neurological disability due to limited axonal regeneration. Injury-dependent and -independent mechanisms have provided important insight into neuronal regeneration, however, common denominators underpinning regeneration remain elusive. A comparative analysis of transcriptomic datasets associated with neuronal regenerative ability revealed circadian rhythms as the most significantly enriched pathway. Subsequently, we demonstrated that sensory neurons possess an endogenous clock and that their regenerative ability displays diurnal oscillations in a murine model of sciatic nerve injury. Consistently, transcriptomic analysis showed a time-of-day-dependent enrichment for processes associated with axonal regeneration and the circadian clock. Conditional deletion experiments demonstrated that Bmal1 is required for neuronal intrinsic circadian regeneration and target re-innervation. Lastly, lithium enhanced nerve regeneration in wild-type but not in clock-deficient mice. Together, these findings demonstrate that the molecular clock fine-tunes the regenerative ability of sensory neurons and propose compounds affecting clock pathways as a novel approach to nerve repair.
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Relojes Circadianos , Ratones , Animales , Relojes Circadianos/genética , Ritmo Circadiano , Regeneración Nerviosa/fisiología , Células Receptoras Sensoriales , Factores de Transcripción ARNTL/genéticaRESUMEN
Tailoring the secondary surface morphology of electro-spun nanofibers has been highly desired, as such delicate structures equip nanofibers with distinct functions. Here, we report a simple strategy to directly reconstruct the surface of polyvinyl alcohol/polyvinylpyrrolidone (PVA/PVP) nanofibers by water evaporation. The roughness and diameter of the nanofibers depend on the temperature during vacuum drying. Surface changes of the nanofibers from smooth to rough were observed at 55 °C, with a significant drop in nanofiber diameter. We attribute the formation of the secondary surface morphology to the intermolecular forces in the water vapor, including capillary and the compression forces, on the basis of the results from the Fourier-transform infrared (FTIR) and X-ray photoelectron (XPS) spectroscopy. The strategy is universally effective for various electro-spun polymer nanofibers, thus opening up avenues toward more detailed and sophisticated structure design and implementation for nanofibers.
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This work presents a highly secure anticounterfeiting strategy based on upconversion/afterglow hybrids with tricolor emissions tuned by a single 975 nm laser. The hybrids are composed of NaYF4:Yb/Tm and NaYF4:Yb/Er microrods and CaS:Eu2+ afterglow phosphors. Under 975 nm excitation, the hybrids exhibit multicolor emissions from green to white by adjusting laser power and then emit red afterglow light when the 975 nm laser is off. Under synergistic excitation of the blue-green light emitted by Tm/Er microrods, the red afterglow emission not only has a strong initial intensity but also lasts for 3 s. Obvious trichromatic changes from green to white to red can be observed by the naked eye. A pattern printed by the hybrid ink exhibits tricolor emissions by laser adjustment and switch. This proves that upconversion/afterglow hybrids are an excellent candidate for anticounterfeiting applications with high-level security but a simple recognition method.
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During laparoscopic surgery, the Veress needle is commonly used in pneumoperitoneum establishment. Precise placement of the Veress needle is still a challenge for the surgeon. In this study, a computer-aided endoscopic optical coherence tomography (OCT) system was developed to effectively and safely guide Veress needle insertion. This endoscopic system was tested by imaging subcutaneous fat, muscle, abdominal space, and the small intestine from swine samples to simulate the surgical process, including the situation with small intestine injury. Each tissue layer was visualized in OCT images with unique features and subsequently used to develop a system for automatic localization of the Veress needle tip by identifying tissue layers (or spaces) and estimating the needle-to-tissue distance. We used convolutional neural networks (CNNs) in automatic tissue classification and distance estimation. The average testing accuracy in tissue classification was 98.53 ± 0.39%, and the average testing relative error in distance estimation reached 4.42 ± 0.56% (36.09 ± 4.92 µm).
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Laparoscopía , Tomografía de Coherencia Óptica , Animales , Computadores , Laparoscopía/métodos , Agujas , Redes Neurales de la Computación , PorcinosRESUMEN
In this paper, the Ir-modified MoS2 monolayer is suggested as a novel gas sensor alternative for detecting the characteristic decomposition products of SF6, including H2S, SO2, and SOF2. The corresponding adsorption properties and sensing behaviors were systematically studied using the density functional theory (DFT) method. The theoretical calculation indicates that Ir modification can enhance the surface activity and improve the conductivity of the intrinsic MoS2. The physical structure formation, the density of states (DOS), deformation charge density (DCD), molecular orbital theory analysis, and work function (WF) were used to reveal the gas adsorption and sensing mechanism. These analyses demonstrated that the Ir-modified MoS2 monolayer used as sensing material displays high sensitivity to the target gases, especially for H2S gas. The gas sensitivity order and the recovery time of the sensing material to decomposition products were reasonably predicted. This contribution indicates the theoretical possibility of developing Ir-modified MoS2 as a gas sensor to detect characteristic decomposition gases of SF6.