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Due to the ability of changing light propagation path direction, curved waveguide Bragg grating (CWG) plays an important role in photonic integrated circuits. In this paper, we proposed a cascaded sampled Bragg grating on tilted waveguide (CSBG-TW) structure to equivalently realize CWG. As an example, by designing two-dimensional (2D) sampled gratings, the direction of +1st sub-grating vector in CSBG-TW can be changed. Then if a curved waveguide is divided into several sections of tilted waveguide, we can keep the grating direction being always parallel to the longitudinal direction of each section of tilted waveguide, while the basic grating is uniform. Hence, the required CWG can be equivalently realized, and the light responses such as reflection Bragg wavelength shift and backward mode convert caused by the tilted grating in curved waveguide can be compensated for. The results show that the sampling structures of CSBG-TW is micro-scale and the difference between reflection intensity between the CSBG-TW with four section tilted waveguide and CWG as design target is less than 0.1 dB. Compared with CWG, the CSBG-TW allows convenient holographic exposure and the wavelength can be accurately controlled. Therefore, the CSBG-TW can be used in various photonic integrated devices that require changing propagation paths.
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Liquid-assisted hard tissue ablation by infrared lasers has extensive clinical application. However, detailed studies are still needed to explore the underlying mechanism. In the present study, the dynamic process of bubble evolution induced by Ho:YAG laser under water without and with bone tissue at different thickness layer were studied, as well as its effects on hard tissue ablation. The results showed that the Ho:YAG laser was capable of ablating hard bone tissue effectively in underwater conditions. The penetration of Ho:YAG laser can be significantly increased up to about 4 mm with the assistance of bubble. The hydrokinetic forces associated with the bubble not only contributed to reducing the thermal injury to peripheral tissue, but also enhanced the ablation efficiency and improve the ablation crater morphology. The data also presented some clues to optimal selection of irradiation parameters and provided additional knowledge of the bubble-assisted hard tissue ablation mechanism.
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Huesos/cirugía , Terapia por Láser/métodos , Láseres de Estado Sólido/uso terapéutico , AguaRESUMEN
Hearing loss following laser-assisted ear surgery has been reported. However, the mechanism responsible for the hearing loss remains largely speculative. The aim of this study was to investigate the correlation between laser-induced hearing loss and changes in the number of hair cell ribbon synapses and ultrastructure in the cochlea. Laser cochleostomy was performed with a superpulsed carbon dioxide (CO2) laser at 2 and 5 W in Sprague-Dawley rats. Auditory brainstem responses (ABRs) were measured preoperatively and 2 days after surgery. The synapse numbers in apical and middle cochlear turns were quantified. Transmission electron microscopy was employed to further examine the subcellular changes in the cochlea. Click and tonal ABR threshold shifts in both 2 and 5-W groups displayed a frequency-dependent loss within the frequency range measured. Laser cochleostomy induced a significant decrease of synapse numbers in the middle turn in both groups (p < 0.05). Electron microscopy data indicated varying degrees of auditory nerve degeneration in both groups. Auditory nerve degeneration might contribute to laser-caused hearing loss even under low-energy laser cochleostomy. The high-energy laser-induced hearing loss was associated with more reduction of synapse number.
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Cóclea/cirugía , Pérdida Auditiva/etiología , Terapia por Láser/efectos adversos , Estomía/métodos , Animales , Cóclea/ultraestructura , Nervio Coclear/fisiopatología , Modelos Animales de Enfermedad , Potenciales Evocados Auditivos del Tronco Encefálico , Femenino , Terapia por Láser/métodos , Microscopía Electrónica de Transmisión , Degeneración Nerviosa , Estomía/efectos adversos , Ratas Sprague-DawleyRESUMEN
Monitoring vital signs is a key part of standard medical care for cancer patients. However, the traditional methods have instability especially when big fluctuations of signals happen, while the deep-learning-based methods lack pertinence to the sensors. A dual-path micro-bend optical fiber sensor and a targeted model based on the Divided-Frequency-CNN (DFC) are developed in this paper to measure the heart rate (HR) and respiratory rate (RR). For each path, features of frequency division based on the mechanism of signal periodicity cooperate with the operation of stable phase extraction to reduce the interference of body movements for monitoring. Then, the DFC model is designed to learn the inner information from the features robustly. Lastly, a weighted strategy is used to estimate the HR and RR via dual paths to increase the anti-interference for errors from one source. The experiments were carried out on the actual clinical data of cancer patients by a hospital. The results show that the proposed method has good performance in error (3.51 (4.51 %) and 2.53 (3.28 %) beats per minute (bpm) for cancer patients with pain and without pain respectively), relevance, and consistency with the values from hospital equipment. Besides, the proposed method significantly improved the ability in the report time interval (30 to 9 min), and mean / confidential interval (3.60/[-22.61,29.81] to -0.64 / [-9.21,7.92] for patients with pain and 1.87 / [-5.49,9.23] to -0.16 / [-6.21,5.89] for patients without pain) compared with our previous work.
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Frecuencia Cardíaca , Neoplasias , Frecuencia Respiratoria , Procesamiento de Señales Asistido por Computador , Signos Vitales , Humanos , Neoplasias/fisiopatología , Monitoreo Fisiológico/métodos , Monitoreo Fisiológico/instrumentación , Signos Vitales/fisiología , Frecuencia Cardíaca/fisiología , Frecuencia Respiratoria/fisiología , Redes Neurales de la Computación , Masculino , Aprendizaje Profundo , Femenino , Persona de Mediana Edad , AdultoRESUMEN
Implant-associated infections due to the formation of bacterial biofilms pose a serious threat in medical healthcare, which needs effective therapeutic methods. Here, we propose a multifunctional nanoreactor by spatiotemporal ultrasound-driven tandem catalysis to amplify the efficacy of sonodynamic and chemodynamic therapy. By combining piezoelectric barium titanate with polydopamine and copper, the ultrasound-activated piezo-hot carriers transfer easily to copper by polydopamine. It boosts reactive oxygen species production by piezoelectrics, and facilitates the interconversion between Cu2+ and Cu+ to promote hydroxyl radical generation via Cu+ -catalyzed chemodynamic reactions. Finally, the elevated reactive oxygen species cause bacterial membrane structure loosening and DNA damage. Transcriptomics and metabolomics analysis reveal that intracellular copper overload restricts the tricarboxylic acid cycle, promoting bacterial cuproptosis-like death. Therefore, the polyetherketoneketone scaffold engineered with the designed nanoreactor shows excellent antibacterial performance with ultrasound stimulation and promotes angiogenesis and osteogenesis on-demand in vivo.
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Antibacterianos , Cobre , Especies Reactivas de Oxígeno , Ultrasonografía , Antibacterianos/farmacología , CatálisisRESUMEN
The continuous monitoring of vital signs is one of the hottest topics in healthcare. Recent technological advances in sensors, signal processing, and image processing spawned the development of no-contact techniques such as remote photoplethysmography (rPPG). To solve the common problems of rPPG including weak extracted signals, body movements, and generalization with limited data resources, we proposed a dual-path estimation method based on video magnification and deep learning. First, image processes are applied to detect, track, and magnificate facial ROIs automatically. Then, the steady part of the wave of each processed ROI is used for the extraction of features including heart rate, PTT, and features of pulse wave waveform. The blood pressures are estimated from the features via a small CNN. Results comply with the current standard and promise potential clinical applications in the future.
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A strong fluorescence background is one of the common interference factors of Raman spectroscopic analysis in biological tissue. This study developed an endoscopic shifted-excitation Raman difference spectroscopy (SERDS) system for real-time in vivo detection of nasopharyngeal carcinoma (NPC) for the first time. Owing to the use of the SERDS method, the high-quality Raman signals of nasopharyngeal tissue could be well extracted and characterized from the complex raw spectra by removing the fluorescence interference signals. Significant spectral differences relating to proteins, phospholipids, glucose, and DNA were found between 42 NPC and 42 normal tissue sites. Using linear discriminant analysis, the diagnostic accuracy of SERDS for NPC detection was 100%, which was much higher than that of raw Raman spectroscopy (75.0%), showing the great potential of SERDS for improving the accurate in vivo detection of NPC.
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Neoplasias Nasofaríngeas , Espectrometría Raman , Humanos , Carcinoma Nasofaríngeo , Espectrometría Raman/métodos , Análisis Discriminante , ADN , Neoplasias Nasofaríngeas/química , Neoplasias Nasofaríngeas/diagnósticoRESUMEN
Early screening and precise staging are crucial for reducing mortality in patients with nasopharyngeal carcinoma (NPC). This study aimed to assess the performance of blood protein surface-enhanced Raman scattering (SERS) spectroscopy, combined with deep learning, for the precise detection of NPC. A highly efficient protein SERS analysis, based on a membrane purification technique and super-hydrophobic platform, was developed and applied to blood samples from 1164 subjects, including 225 healthy volunteers, 120 stage I, 249 stage II, 291 stage III, and 279 stage IV NPC patients. The proteins were rapidly purified from only 10 µL of blood plasma using the membrane purification technique. Then, the super-hydrophobic platform was prepared to pre-concentrate tiny amounts of proteins by forming a uniform deposition to provide repeatable SERS spectra. A total of 1164 high-quality protein SERS spectra were rapidly collected using a self-developed macro-Raman system. A convolutional neural network-based deep-learning algorithm was used to classify the spectra. An accuracy of 100% was achieved for distinguishing between the healthy and NPC groups, and accuracies of 96%, 96%, 100%, and 100% were found for the differential classification among the four NPC stages. This study demonstrated the great promise of SERS- and deep-learning-based blood protein testing for rapid, non-invasive, and precise screening and staging of NPC.
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INTRODUCTION: Nasopharyngeal carcinoma, an epithelial-derived malignant tumor which because of its anatomical location and atypical early symptoms, when diagnosed invasion and metastasis often have occurred. This requires a better understanding of the development mechanism, identifying diagnostic markers, and developing new treatment strategies. OBJECTIVE: To study the relationship of LMP1 and Cripto-1 in nasopharyngeal carcinoma. METHODS: The expression of LMP1 and Cripto-1 in specimens obtained from nasopharyngeal carcinoma patients (n=42) and nasopharyngitis patients (n=22) were examined. The expression of LMP1 and Cripto-1 in LMP1-negative and LMP1-positive (CNE1-LMP1) cells were also examined. RESULTS: The expression of LMP1 and Cripto-1 was significantly higher in nasopharyngeal carcinoma than in nasopharyngitis (p<0.05). Their expression in nasopharyngeal carcinoma with metastasis were significantly higher than that without metastasis (p<0.05), which was correlated with TNM staging (p<0.05). High Cripto-1 expression and high proliferation rate were seen in CNE1-LMP1 cells. CONCLUSIONS: The expression of LMP1 and Cripto-1 in nasopharyngeal carcinoma is positively related. Their co-expression might contribute to the proliferation and metastasis of nasopharyngeal carcinoma.
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Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Proteínas de la Membrana Bacteriana Externa , Humanos , Péptidos y Proteínas de Señalización Intercelular , Proteínas de la Matriz ViralRESUMEN
PURPOSE: To visualize and quantify the three-dimensional (3D) spatial relationships of the structures of the aqueous outflow system (AOS) within intact enucleated mouse eyes using spectral two-photon microscopy (TPM) techniques. METHODS: Spectral TPM, including two-photon autofluorescence (TPAF) and second-harmonic generation (SHG), were used to image the small structures of the AOS within the limbal region of freshly enucleated mouse eyes. Long infrared excitation wavelengths (930 nm) were used to reduce optical scattering and autofluorescent background. Image stacks were collected for 3D image rendering and structural segmentation. For anatomical reference, vascular perfusion with fluorescent-conjugated dextran (150 KDa) and trans-corneal perfusion with 0.1 µm fluorescent polystyrene beads were separately performed to identify the episcleral veins (EV) and the trabecular meshwork (TM) and Schlemm's canal (SC), respectively. RESULTS: Three-dimensional rendering and segmentation of spectral two-photon images revealed detailed structures of the AOS, including SC, collector channels (CC), and aqueous veins (AV). The collagen of the TM was detected proximal to SC. The long and short axes of the SC were 82.2 ± 22.2 µm and 6.7 ± 1.4 µm. The diameters of the CC averaged 25.6 ± 7.9 µm where they originated from the SC (ostia), enlarged to 34.1 ± 13.1 µm at the midpoint, and narrowed to 18.3 ± 4.8 µm at the junction of the AV. The diameter of the AV averaged 12.5 ± 3.4 µm. CONCLUSIONS: Spectral TPM can be used to reconstruct and measure the spatial relationships of both large and small AOS structures, which will allow for better understanding of distal aqueous outflow dynamics.
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Humor Acuoso/metabolismo , Imagenología Tridimensional/métodos , Presión Intraocular/fisiología , Microscopía/métodos , Fotones , Malla Trabecular/diagnóstico por imagen , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos Animales , Reproducibilidad de los Resultados , Malla Trabecular/metabolismoRESUMEN
Abstract Introduction: Nasopharyngeal carcinoma, an epithelial-derived malignant tumor which because of its anatomical location and atypical early symptoms, when diagnosed invasion and metastasis often have occurred. This requires a better understanding of the development mechanism, identifying diagnostic markers, and developing new treatment strategies. Objective: To study the relationship of LMP1 and Cripto-1 in nasopharyngeal carcinoma. Methods: The expression of LMP1 and Cripto-1 in specimens obtained from nasopharyngeal carcinoma patients (n = 42) and nasopharyngitis patients (n = 22) were examined. The expression of LMP1 and Cripto-1 in LMP1-negative and LMP1-positive (CNE1-LMP1) cells were also examined. Results: The expression of LMP1 and Cripto-1 was significantly higher in nasopharyngeal carcinoma than in nasopharyngitis (p < 0.05). Their expression in nasopharyngeal carcinoma with metastasis were significantly higher than that without metastasis (p < 0.05), which was correlated with TNM staging (p < 0.05). High Cripto-1 expression and high proliferation rate were seen in CNE1-LMP1 cells. Conclusions: The expression of LMP1 and Cripto-1 in nasopharyngeal carcinoma is positively related. Their co-expression might contribute to the proliferation and metastasis of nasopharyngeal carcinoma.
Resumo Introdução: O carcinoma nasofaríngeo é um tumor maligno derivado do epitélio de localização anatômica recôndita e sintomas iniciais atípicos; quando diagnosticado, frequentemente invasão e metástases já ocorreram. Isso requer uma melhor compreensão do seu mecanismo de desenvolvimento, identificação dos marcadores diagnósticos e desenvolvimento de novas estratégias de tratamento. Objetivo: Estudar a relação de LMP1 e Cripto-1 no carcinoma nasofaríngeo. Método: A expressão de LMP1 e Cripto-1 em espécimes obtidos de pacientes com carcinoma de nasofaringe (n = 42) e pacientes com nasofaringite (n = 22) foi analisada. A expressão de LMP1 e Cripto-1 em células LMP1-negativas e LMP1-positivas (CNE1-LMP1) também foi analisada. Resultados: A expressão de LMP1 e Cripto-1 foi significantemente maior na presença de carcinoma nasofaríngeo do que na nasofaringite (p < 0,05). Sua expressão em carcinomas com metástase foi significantemente maior do que em casos sem metástase (p < 0,05), o que se correlacionou com o estadiamento TNM (p < 0,05). Uma alta expressão de Cripto-1 e alta taxa de proliferação foram observadas nas células CNE1-LMP1. Conclusões: A expressão de LMP1 e Cripto-1 é positivamente relacionada com carcinoma nasofaríngeo. Sua coexpressão pode ser atribuída à proliferação e metástase do tumor.
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Humanos , Neoplasias Nasofaríngeas , Carcinoma Nasofaríngeo , Proteínas de la Membrana Bacteriana Externa , Proteínas de la Matriz Viral , Péptidos y Proteínas de Señalización IntercelularRESUMEN
OBJECTIVE: To investigate the effects on ribbon synapse of inner hair cells after superpulsed CO2 laser-assisted cochleostomy in SD rats. METHODS: Eighteen SD rats were randomly divided into laser-assisted surgery groups (2 W group and 5 W group), sham-operated group and control group. Ten of those were performed a cochleostomy using superpulsed CO2 laser with a corresponding power. Auditory brainstem responses (ABR) were measured pre-and postoperatively. The ribbon synapses at apical and middle cochlear turns were observed under laser scanning confocal microscope and then were quantified with 3ds Max software. RESULTS: The postoperative ABR thresholds of the 2 W and 5 W groups were larger than the preoperative case (t = -5.65, P < 0.01; t = -4.97, P < 0.01). The synapse number at the middle turn decreased significantly in 5 W group (F = 17.15, P < 0.01), while no significant changes were noted at the apical turn (P > 0.05). There was no statistical difference in 2 W group (P > 0.05). CONCLUSIONS: The superpulsed CO2 laser-assisted cochleostomy with high-power is accompanied by a synaptic injury, while no obvious effects after the low-power laser surgery, which might be a safe strategy to preform cochleostomy.
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Cóclea/cirugía , Células Ciliadas Auditivas Internas/efectos de la radiación , Láseres de Gas/efectos adversos , Sinapsis/efectos de la radiación , Animales , Terapia por Láser , Distribución Aleatoria , Ratas , Ratas Sprague-DawleyRESUMEN
The theory of hard tissue ablation reported for IR lasers is based on a process of thermomechanical interaction, which is explained by the absorption of the radiation in the water component of the tissue. The microexplosion of the water is the cause of tissue fragments being blasted from hard tissue. The aim of this study is to evaluate the influence of the interdependence of water layer thickness and incident radiant exposure on ablation performance. A total of 282 specimens of bovine shank bone were irradiated with a pulse CO(2) laser. Irradiation was carried out in groups: without a water layer and with a static water layer of thickness ranging from 0.2 to 1.2 mm. Each group was subdivided into five subgroups for different radiant exposures ranging from 18 to 84 J/cm(2), respectively. The incision geometry, surface morphology, and microstructure of the cut walls as well as thermal injury were examined as a function of the water layer thickness at different radiant exposures. Our results demonstrate that the additional water layer is actually a mediator of laser-tissue interaction. There exists a critical thickness of water layer for a given radiant exposure, at which the additional water layer plays multiple roles, not only acting as a cleaner to produce a clean cut but also as a coolant to prevent bone heating and reduce thermal injury, but also helping to improve the regularity of the cut shape, smooth the cut surface, and enhance ablation rate and efficiency. The results suggest that desired ablation results depend on optimal selection of both water layer thickness and radiant exposure.