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1.
Plant Cell ; 35(5): 1304-1317, 2023 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-36724050

RESUMEN

Although many studies have elucidated the mechanisms by which different wavelengths of light (blue, red, far-red, or ultraviolet-B [UV-B]) regulate plant development, whether and how green light regulates plant development remains largely unknown. Previous studies reported that green light participates in regulating growth and development in land plants, but these studies have reported conflicting results, likely due to technical problems. For example, commercial green light-emitting diode light sources emit a little blue or red light. Here, using a pure green light source, we determined that unlike blue, red, far-red, or UV-B light, which inhibits hypocotyl elongation, green light promotes hypocotyl elongation in Arabidopsis thaliana and several other plants during the first 2-3 d after planting. Phytochromes, cryptochromes, and other known photoreceptors do not mediate green-light-promoted hypocotyl elongation, but the brassinosteroid (BR) signaling pathway is involved in this process. Green light promotes the DNA binding activity of BRI1-EMS-SUPPRESSOR 1 (BES1), a master transcription factor of the BR pathway, thus regulating gene transcription to promote hypocotyl elongation. Our results indicate that pure green light promotes elongation via BR signaling and acts as a shade signal to enable plants to adapt their development to a green-light-dominant environment under a canopy.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Hipocótilo , Brasinoesteroides/metabolismo , Arabidopsis/metabolismo , Transducción de Señal , Regulación de la Expresión Génica de las Plantas
2.
Opt Express ; 32(8): 14860-14875, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38859421

RESUMEN

In contrast to the current athermal map's lack of intuitiveness, we introduce a novel composite athermal map to visually evaluate the potential of lens system glass materials in achieving athermal and achromatic designs. Furthermore, unlike graphically manual methods for athermalization, we propose an automatic method to athermalize the optical system by glass selection using simulated annealing with memory augmentation (GlaSAM). This method employs a comprehensive objective function that integrates thermal aberration, chromatic aberration, secondary spectrum aberration, and Petzval curvature aberration. Weight factors are introduced to evaluate each aberration in the function, and filters are applied to streamline the search space. Additionally, the augmentation of memory into the optimization algorithm not only enhances its efficiency but also safeguards against overlooking solutions with superior imaging quality. To test the advantage of the GlaSAM method, a complex telephoto design is optimized to function across a temperature range from -40°C to 70°C, and the results demonstrate the efficacy of athermalizing the lens system while preserving exceptional imaging performance through this proposed method.

3.
Lasers Med Sci ; 38(1): 203, 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37668791

RESUMEN

Previous research has demonstrated the beneficial effect brought by transcranial photobiomodulation (tPBM). The present study is a further investigation of pulsed transcranial light delivery, from the perspective of wavelength, operation mode, and pulse frequency. A total of 56 healthy young adults (28 males and 28 females) were included in this randomized, sham-controlled experimental study. The wavelength of tPBM was 660 nm and 850 nm, and under each wavelength, subjects were randomly assigned to one of the following four treatments: (1) sham control; (2) continuous-wave (CW) tPBM; (3) pulsed-wave (PW) tPBM (40 Hz); and (4) PW tPBM (100 Hz). The tPBM duration was 8 min and the mean power density was fixed at 250 mW/cm2. Karolinska Sleepiness Scale (KSS) questionnaire, psychomotor vigilance task (PVT), and delayed match-to-sample (DMS) task were completed by subjects before and after the intervention to test whether PW tPBM produced distinct beneficial effects with measures of sleepiness, attention, and memory. 32-channel electroencephalography (EEG) signals were obtained from subjects before, during and after receiving tPBM or sham intervention. Paired sample T test showed that the KSS score, the number of correct responses of PVT, and DMS rate correct score (RCS) of PW tPBM groups improved significantly after intervention (p < 0.05). With regard to EEG analysis, paired one-way repeated ANOVA test showed that during the intervention of PW tPBM, the average power within the Gamma band was higher than the baseline (p < 0.05). Our study presented that PW tPBM could generate better beneficial cognitive effects and change brain electrical activity under certain circumstances.


Asunto(s)
Electroencefalografía , Somnolencia , Femenino , Masculino , Adulto Joven , Humanos , Rayos gamma , Estado de Salud , Frecuencia Cardíaca
4.
Lasers Med Sci ; 38(1): 71, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36790539

RESUMEN

Photobiomodulation (PBM) is the use of low irradiance light of specific wavelengths to generate physiological changes and therapeutic effects. However, there are few studies on the effects of PBM of different LED light modes on cells. Here, we investigated the difference of influence between continuous wave (CW) and pulse-PBM on B16F10 melanoma cells. Our results suggested that the pulse mode had a more significant PBM than the CW mode on B16F10 melanoma cells. Our study confirmed that ROS and Ca2+ levels in B16F10 melanoma cells treated with pulse-PBM were significantly higher than those in the control and CW-PBM groups. One mechanism that causes the difference in CW and pulse-PBM action is that pulse-PBM activates autophagy of melanoma cells through the ROS/OPN3/Ca2+ signaling pathway, and excessive autophagy activation inhibits proliferation and apoptosis of melanoma cells. Autophagy may be one of the reasons for the difference between pulse- and CW-PBM on melanoma cells. More importantly, melanoma cells responded to brief PBM pulses by increasing intracellular Ca2+ levels.


Asunto(s)
Terapia por Luz de Baja Intensidad , Melanoma , Humanos , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Autofagia , Melanoma/radioterapia , Terapia por Luz de Baja Intensidad/métodos , Opsinas de Bastones
5.
Clin Oral Investig ; 27(9): 5287-5296, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37490116

RESUMEN

OBJECTIVES: On the basis of a large sample size and a long follow-up period, the objectives of this study were to evaluate the outcomes of direct pulp capping (DPC) in mature permanent teeth with carious pulp exposure using a kind of bioaggregate putty (BP) which commercially named iRoot BP Plus (Innovative Bioceramix, Inc., Vancouver, Canada) and to analyze the potential prognostic factors. MATERIALS AND METHODS: The design of this research was retrospective regarding treatment procedures and prospective regarding the assessment of outcomes. The preoperative diagnosis of the teeth was either normal pulp or reversible pulpitis. Results were assessed based on clinical and radiographic examinations with at least 12 months of follow-up after DPC. No symptoms or signs, a positive response to electric pulp testing, a normal response to cold pulp testing and radiographs showing no abnormalities were considered to indicate success. Kaplan-Meier survival analysis was used to calculate the cumulative survival of teeth after DPC. Univariate and multivariate Cox proportional hazard regressions were used to analyze potential prognostic factors. RESULTS: Three hundred thirty-four patients, including a total of 354 teeth, were available for the final clinical examination. The follow-up period ranged from 12 to 85 months, with an average of 27.0 ± 0.8 months. The total success rate was 85% (302/354), and the cumulative survival rates at 1, 2, 3, 4, and 5 years were 92%, 87%, 83%, 76%, and 72%, respectively. Univariate analysis indicated a significantly increased risk of failure in patients aged above 40 years and those treated by resident operators (P ≤ 0.01), with hazard ratios of 2.18 and 2.27, respectively. CONCLUSIONS: Under appropriate indication selection and treatment procedures, long-term success is possible in mature permanent teeth with carious pulp exposure by DPC using iRoot BP Plus. Patient age and operator experience are potential prognostic factors. CLINICAL RELEVANCE: Clinical data on iRoot BP Plus as a pulp capping medicament in mature permanent teeth with carious pulp exposure is lacking. This study indicated the efficacy of BP in DPC. Younger patient and sophisticated operator are beneficial for the outcome of DPC.


Asunto(s)
Caries Dental , Materiales de Recubrimiento Pulpar y Pulpectomía , Humanos , Anciano , Pronóstico , Recubrimiento de la Pulpa Dental/métodos , Estudios Retrospectivos , Estudios Prospectivos , Compuestos de Calcio/uso terapéutico , Materiales de Recubrimiento Pulpar y Pulpectomía/uso terapéutico , Caries Dental/terapia , Caries Dental/tratamiento farmacológico , Silicatos/uso terapéutico , Óxidos/uso terapéutico , Resultado del Tratamiento
6.
Langmuir ; 38(44): 13477-13487, 2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36306177

RESUMEN

The investigation of the strength and toughness of poly(l-lactic acid) (PLLA) monofilaments is essential as the fundamental element of a biodegradable braided stent. However, the determining factor remains poorly addressed with respect to influencing the mechanical behavior of PLLA monofilaments. In this work, the electron beam (EB) with different radiation doses was utilized to sterilize PLLA monofilaments. Properties of the monofilaments, including the breaking strength, elongation at break, molecular weight, orientation, and microstructure of the fracture, were characterized. Results showed that a random chain scission of PLLA resulting from EB during this process could cause the decrease in molecular weight, which led to the decline in breaking strength. Meanwhile, the irradiated monofilaments were found to have almost the same elongation at break below a dose of 30 kGy and declined by 71.41% up to a dose of 48 kGy. It was also found that the ductile fracture connection of the monofilament translated to the brittle fracture by comparing the microstructure without and with sterilization. These phenomena could originate from the destruction of the long molecular chains connecting the crystal plates into shorter ones by radiation. PLLA monofilaments with 0, 30, and 48 kGy were used to braid carotid stents. Compared with a carotid Wallstent, the PLLA stent can better provide radial supporting to the carotid lesion. This study provides preliminary experimental references to evaluate and predict the mechanical performance of PLLA braided stents.


Asunto(s)
Implantes Absorbibles , Poliésteres , Poliésteres/química , Stents , Resistencia a la Tracción
7.
Photodermatol Photoimmunol Photomed ; 38(1): 3-11, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34181781

RESUMEN

Photobiomodulation (PBM) uses low-intensity visible or near-infrared light to produce beneficial effects on cells or tissues, such as brain therapy, wound healing. Still there is no consistent recommendation on the parameters (dose, light mode, wavelength, irradiance) and protocols (repetition, treatment duration) for its clinical application. Herein, we summarize the current PBM parameters for the treatment of melanoma, and we also discuss the potential photoreceptors and downstream signaling mechanisms in the PBM treatment of melanoma cells. It is hypothesized that PBM may inhibit the melanoma cells by activating mitochondria, OPNs, and other receptors. Regardless of the underlying mechanisms, PBM has been shown to be beneficial in treating melanoma. Through further in-depth studies of the underlying potential mechanisms, it can strengthen the applications of PBM for the therapy of melanoma.


Asunto(s)
Terapia por Luz de Baja Intensidad , Melanoma , Humanos , Rayos Infrarrojos , Melanoma/radioterapia , Transducción de Señal , Cicatrización de Heridas
8.
Photodermatol Photoimmunol Photomed ; 38(4): 311-321, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34907599

RESUMEN

The use of light-emitting diode (LED)-based photodynamic therapies in the treatment of periodontitis is increasing because these modalities are effective, safe, and painless. They are not subject to acquired drug resistance or environmental issues and are associated with no complications when used appropriately. These light sources have also been used in combination with pharmacological measures to synergize their effects and optimize therapeutic outcomes. This review focuses on optical devices used in treating periodontitis and delineates the current applications of various methods, including their utility and efficacy. The application of LEDs in periodontology is described.


Asunto(s)
Antiinfecciosos , Periodontitis , Fotoquimioterapia , Antibacterianos , Humanos , Periodontitis/tratamiento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico
9.
Hepatobiliary Pancreat Dis Int ; 21(6): 543-550, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35705443

RESUMEN

BACKGROUND: Early recurrence results in poor prognosis of patients with hepatocellular carcinoma (HCC) after liver transplantation (LT). This study aimed to explore the value of computed tomography (CT)-based radiomics nomogram in predicting early recurrence of patients with HCC after LT. METHODS: A cohort of 151 patients with HCC who underwent LT between December 2013 and July 2019 were retrospectively enrolled. A total of 1218 features were extracted from enhanced CT images. The least absolute shrinkage and selection operator algorithm (LASSO) logistic regression was used for dimension reduction and radiomics signature building. The clinical model was constructed after the analysis of clinical factors, and the nomogram was constructed by introducing the radiomics signature into the clinical model. The predictive performance and clinical usefulness of the three models were evaluated using receiver operating characteristic (ROC) curve analysis and decision curve analysis (DCA), respectively. Calibration curves were plotted to assess the calibration of the nomogram. RESULTS: There were significant differences in radiomics signature among early recurrence patients and non-early recurrence patients in the training cohort (P < 0.001) and validation cohort (P < 0.001). The nomogram showed the best predictive performance, with the largest area under the ROC curve in the training (0.882) and validation (0.917) cohorts. Hosmer-Lemeshow testing confirmed that the nomogram showed good calibration in the training (P = 0.138) and validation (P = 0.396) cohorts. DCA showed if the threshold probability is within 0.06-1, the nomogram had better clinical usefulness than the clinical model. CONCLUSIONS: Our CT-based radiomics nomogram can preoperatively predict the risk of early recurrence in patients with HCC after LT.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Trasplante de Hígado , Humanos , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/cirugía , Carcinoma Hepatocelular/patología , Nomogramas , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/patología , Trasplante de Hígado/efectos adversos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
10.
Clin Oral Investig ; 26(1): 981-991, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34312683

RESUMEN

OBJECTIVES: The objective of our study was to develop and validate a deep learning approach based on convolutional neural networks (CNNs) for automatic detection of the mandibular third molar (M3) and the mandibular canal (MC) and evaluation of the relationship between them on CBCT. MATERIALS AND METHODS: A dataset of 254 CBCT scans with annotations by radiologists was used for the training, the validation, and the test. The proposed approach consisted of two modules: (1) detection and pixel-wise segmentation of M3 and MC based on U-Nets; (2) M3-MC relation classification based on ResNet-34. The performances were evaluated with the test set. The classification performance of our approach was compared with two residents in oral and maxillofacial radiology. RESULTS: For segmentation performance, the M3 had a mean Dice similarity coefficient (mDSC) of 0.9730 and a mean intersection over union (mIoU) of 0.9606; the MC had a mDSC of 0.9248 and a mIoU of 0.9003. The classification models achieved a mean sensitivity of 90.2%, a mean specificity of 95.0%, and a mean accuracy of 93.3%, which was on par with the residents. CONCLUSIONS: Our approach based on CNNs demonstrated an encouraging performance for the automatic detection and evaluation of the M3 and MC on CBCT. Clinical relevance An automated approach based on CNNs for detection and evaluation of M3 and MC on CBCT has been established, which can be utilized to improve diagnostic efficiency and facilitate the precision diagnosis and treatment of M3.


Asunto(s)
Aprendizaje Profundo , Tomografía Computarizada de Haz Cónico Espiral , Tomografía Computarizada de Haz Cónico , Canal Mandibular , Diente Molar , Tercer Molar/diagnóstico por imagen
11.
Molecules ; 27(19)2022 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-36235228

RESUMEN

Oxygen exposure is unavoidable and the impact of its management during the post-fermentation stage (PFS) on dry red wine is poorly investigated. This study was dedicated to the variation of acetaldehyde, color and phenolics of Cabernet Sauvignon dry red wine during five discontinuous oxidation cycles of four levels of controlled oxygen supply, which were carried out to simulate probable oxidation during the PFS. Free SO2 disappeared after the first, second and third oxidation cycles in wines with high, medium and low levels of oxygen exposure severally, but subsequent oxygen exposure below or equal to 2 mg O2/L per cycle had little effect while 3-3.9 mg O2/L per cycle dramatically facilitated acetaldehyde accumulation, which was accompanied by an enormous variation in color and pigments, especially when total oxygen consumption was above 10 mg/L. The utilization of clustered heatmap and partial least square regression demonstrated the feasibility of characterization of wine oxidation degree using the chemical parameters measured by UV-spectrophotometry. Oxygen exposure during the PFS should be emphatically controlled, and chemical indexes determined by the UV-spectrophotometric method can be used for a scientific and effective description of wine oxidation degree.


Asunto(s)
Vitis , Acetaldehído , Antocianinas , Color , Fermentación , Oxígeno/química , Fenoles , Vitis/química
12.
Photodermatol Photoimmunol Photomed ; 36(4): 299-307, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32187726

RESUMEN

BACKGROUND: The photobiomodulation (PBM) effect has been applied to various clinical therapy for a long time. However, the mechanism related to the PBM effect in terms of wavelengths has been lack of in-depth study, except that ultraviolet radiation has attracted much attention due to its strong cell-killing effect. PURPOSE: To clarify the principle behind PBM and the main mechanism of improvement. METHODS: To carry on this study, we created light equipment using three LED chips, which emit 390 nm ultraviolet radiation, 415 nm blue light and 660 nm red light, respectively. We choose human fibroblasts (HF) to be irradiated by three different wavelengths for PBM test. In this study, we used cell counting kit (CCK-8) test to show the cell proliferation roughly and reported on a systematic RNA sequencing (RNA-seq) analysis at transcriptional expression levels from HF, which accepted PBM of different wavelengths of light. RESULTS: We found that 415 nm blue light inhibited cell proliferation and 660 nm red light stimulated cell proliferation while 390 nm ultraviolet radiation has little influence on cell proliferation. Furthermore, RNA-seq results showed that CSF1R, PPP3CC, ITGAL, ITGAM, IL2RB, and several other differentially expressed genes (DEGs) are involved in the cell proliferation. Relative DEGs values for matrix metalloproteinases (MMPs) gene family have shown a great difference in blue and red light radiation especially on MMP25, MMP9, MMP21, and MMP13. CONCLUSION: Taken together, the results provide a valuable resource to describe the variation of HFs under PBM of different light at gene level.


Asunto(s)
Proliferación Celular/efectos de la radiación , Fibroblastos/fisiología , Terapia por Luz de Baja Intensidad , Metaloproteinasas de la Matriz/genética , Transducción de Señal/genética , Rayos Ultravioleta , Color , Humanos , Análisis de Secuencia de ARN , Transcriptoma
13.
Appl Opt ; 58(11): 2803-2808, 2019 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-31044880

RESUMEN

The technique of using monochromatic light-emitting diodes (LEDs) to simulate sunlight has been developed rapidly in recent years. In this research, we propose a method to improve the simulating performance based on the influence of the driving current (70 to 700 mA) on the peak wavelength of monochromatic LEDs. The largest shift of the peak wavelength was observed in the green-light LED with 9 nm deviation. A modified Gaussian formula with an additional variable, driving current I, was used to simulate the LED power spectrum, and was further employed in an optimizing algorithm to achieve solar spectrum matching by 14 types of LEDs with different peak wavelengths.

14.
J Oral Rehabil ; 46(8): 704-714, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31009097

RESUMEN

BACKGROUND: Anterior repositioning splint (ARS) can facilitate regenerative condylar remodelling. OBJECTIVE: To determine the effect of ARS on osseous condylar changes in adolescents/young adults with early-stage degenerative joint disease (DJD). METHODS: Sixty-nine patients with early-stage temporomandibular joint (TMJ) DJD based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) and cone beam computed tomography (CBCT) imaging were recruited and randomly allocated to two treatment groups: (a) conservative therapy with ARS and (b) conservative therapy without ARS. Subjects with acute TMJ closed-lock had their displaced discs physically reduced by mandibular manipulation prior to ARS therapy. Clinical and CBCT data of 59 patients (86.4% females, mean age 17.95 ± 4.53 years, 67 joints) were attained pre- and at 6 or 12 months post-treatment. Osseous changes after treatment were categorised into (a) progressed, (b) unchanged, (c) repaired (remodelled without new bone formation) and (d) regenerated (remodelled with new bone formation). Statistical analysis including chi-square test, independent samples t test or Mann-Whitney U test was conducted. RESULTS: About 85.5% of patients (59/69) completed the study, with 28 subjects (32 joints) in the splint group and 31 (35 joints) in the control group. The occurrence of condylar repair and regeneration was significantly higher with ARS (78.1%/[25/32] of joints) when compared to control group (48.6%/[17/35]) (P < 0.05). Moreover, condylar regeneration was exclusively observed in 50%/(16/32) of joints with ARS. For the 14 joints in splint group that received physical TMJ closed-lock reduction, 85.7%/(12/14) exhibited condylar regeneration. The splint group (3.1%/[1/32]) also had significantly lower incidence of progressive TMJ degeneration than the control (37.1%/[13/35]) (P < 0.001). CONCLUSION: Condylar repair and regeneration in early-stage TMJ DJD are possible, and ideal spatial disc-condyle relationship appears important. The possibility of restoring TMJ form/structure by ARS therapy presents an attractive area of new basic science and clinical research (Bone defect repair in early osteoarthrosis of temporomandibular joint by joint distraction therapy: A randomized controlled trial/ChiCTR-TRC-14005172).


Asunto(s)
Luxaciones Articulares , Trastornos de la Articulación Temporomandibular , Adolescente , Adulto , Femenino , Humanos , Masculino , Cóndilo Mandibular , Regeneración , Articulación Temporomandibular , Disco de la Articulación Temporomandibular , Adulto Joven
16.
Appl Opt ; 53(35): 8151-6, 2014 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-25608054

RESUMEN

Light emitting diodes (LEDs) are considered next-generation light sources. Because of their narrow emission spectrum, easy adjustment, and various other characteristics, LEDs can be used in many situations, especially those that require dimming or spectral assemblage. In this paper we discuss spectral assemblage with LEDs. We cover possible valid arrangements in a spectrum from 400 to 700 nm by an exhaustive and genetic algorithm, calculate the highest luminous efficacy of a source for each correlated color temperature and color-rendering index, and present the corresponding energy distribution.

17.
Beijing Da Xue Xue Bao Yi Xue Ban ; 46(1): 95-9, 2014 Feb 18.
Artículo en Zh | MEDLINE | ID: mdl-24535357

RESUMEN

OBJECTIVE: To investigate the root canal configuration of mandibular anterior teeth with cone-beam computed tomography (CBCT). METHODS: The CBCT imaging data of 866 patients who visited Peking University School of Stomatology from October 2012 to July 2013 were inspected by an endodontist anda radiologists together. A total of 4 674 mandibular anterior teeth were involved. The number of root, root canals and root canal configuration were observed and analyzed statistically (Chi-squared test). RESULTS: All the mandibular central incisors and lateral incisors were single root, and 0.7% (11/1 542) of canines were double roots. 6.7% (105/1 566) of central incisors, 17.4% (273/1 566) of lateral incisors and 3.0% (46/1 542) of canines had double root canals. The frequency of symmetry of double root canal was 58.7% (37/63) in central incisors, 76.1% (108/142) in lateral incisors and 29.6% (8/27) in canines. The highest frequency of double root canals in different ages was 9.8% (28/287, 31-40 years) in central incisors, 21.5% (61/284, 31-40 years) in lateral incisors and 9.2% (19/207, ≥51 years) in canines. Vertucci type III canal configurations were the most prevalent in mandibular anterior teeth. CONCLUSION: The double root canals are most common in mandibular lateral incisors. The highest incidence of symmetry of double root canal is also observed in mandibular lateral incisors. Vertucci type III canal configurations are the most frequent type in mandibular anterior teeth.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Cavidad Pulpar , Raíz del Diente , Humanos , Incisivo , Mandíbula
18.
Phys Med Biol ; 69(13)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38843814

RESUMEN

Objective.The aim of this study is to address the limitations in reconstructing the electrical activity of the heart from the body surface electrocardiogram, which is an ill-posed inverse problem. Current methods often assume values commonly used in the literature in the absence ofa prioriknowledge, leading to errors in the model. Furthermore, most methods ignore the dynamic activation process inherent in cardiomyocytes during the cardiac cycle.Approach.To overcome these limitations, we propose an extended Kalman filter (EKF)-based neural network approach to dynamically reconstruct cardiac transmembrane potential (TMP). Specifically, a recurrent neural network is used to establish the state estimation equation of the EKF, while a convolutional neural network is used as the measurement equation. The Jacobi matrix of the network undergoes a correction feedback process to obtain the Kalman gain.Main results.After repeated iterations, the final estimated state vector, i.e. the reconstructed image of the TMP, is obtained. The results from both the final simulation and real experiments demonstrate the robustness and accurate quantification of the model.Significance.This study presents a new approach to cardiac TMP reconstruction that offers higher accuracy and robustness compared to traditional methods. The use of neural networks and EKFs allows dynamic modelling that takes into account the activation processes inherent in cardiomyocytes and does not requirea prioriknowledge of inputs such as forward transition matrices.


Asunto(s)
Corazón , Potenciales de la Membrana , Redes Neurales de la Computación , Corazón/diagnóstico por imagen , Corazón/fisiología , Procesamiento de Imagen Asistido por Computador/métodos , Humanos , Animales
19.
J Photochem Photobiol B ; 257: 112963, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38908147

RESUMEN

The therapeutic potential of blue light photobiomodulation in cancer treatment, particularly in inhibiting cell proliferation and promoting cell death, has attracted significant interest. Oral squamous cell carcinoma (OSCC) is a prevalent form of oral cancer, necessitating innovative treatment approaches to improve patient outcomes. In this study, we investigated the effects of 420 nm blue LED light on OSCC and explored the underlying mechanisms. Our results demonstrated that 420 nm blue light effectively reduced OSCC cell viability and migration, and induced G2/M arrest. Moreover, we observed that 420 nm blue light triggered endoplasmic reticulum (ER) stress and mitochondrial dysfunction in OSCC cells, leading to activation of the CHOP signal pathway and alterations in the levels of Bcl-2 and Bax proteins, ultimately promoting cell apoptosis. Additionally, blue light suppressed mitochondrial gene expression, likely due to its damage to mitochondrial DNA. This study highlights the distinct impact of 420 nm blue light on OSCC cells, providing valuable insights into its potential application as a clinical treatment for oral cancer.


Asunto(s)
Apoptosis , Carcinoma de Células Escamosas , Supervivencia Celular , Estrés del Retículo Endoplásmico , Luz , Mitocondrias , Neoplasias de la Boca , Humanos , Estrés del Retículo Endoplásmico/efectos de la radiación , Mitocondrias/efectos de la radiación , Mitocondrias/metabolismo , Neoplasias de la Boca/radioterapia , Neoplasias de la Boca/patología , Neoplasias de la Boca/metabolismo , Línea Celular Tumoral , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/metabolismo , Apoptosis/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Proliferación Celular/efectos de la radiación , Movimiento Celular/efectos de la radiación , Transducción de Señal/efectos de la radiación , Proteína X Asociada a bcl-2/metabolismo , Proteína X Asociada a bcl-2/genética , Factor de Transcripción CHOP/metabolismo , Factor de Transcripción CHOP/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Luz Azul
20.
Aging (Albany NY) ; 16(13): 10868-10881, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38949514

RESUMEN

As a common disease, cervical spondylosis (CS) results from the degeneration of the cervical intervertebral disc. However, there are still no effective clinical strategies for the treatment of this disease. Needle-scalpel (Ns), a therapy guided by traditional Chinese medicine theory, alleviates intervertebral disc degradation and is widely used in the clinic to treat CS. Stromal cell-derived factor-1 (SDF-1) and its receptor CXC receptor 4 (CXCR4) in nucleus pulposus cells play an important role in CS onset and development. This study aimed to explore whether Ns can relieve pain and regulate the SDF-1/CXCR4 axis in nucleus pulposus cells to inhibit apoptosis, thereby delaying cervical intervertebral disc degradation in a rat model of CS. It was found that the Ns-treated groups exhibited higher mechanical allodynia scores than the model group, and H&E staining, MRI, and scanning electron microscopy revealed that Ns therapy inhibited intervertebral disc degeneration. Additionally, Ns therapy significantly inhibited increases in the RNA and protein expression levels of SDF-1 and CXCR4. Furthermore, these treatments alleviated the apoptosis of nucleus pulposus cells, which manifested as a decline in the proportion of apoptotic nucleus pulposus cells and inhibition of the decrease in the levels of Bcl-2/Bax. These findings indicated that Ns mitigated CS-induced pain, inhibited the apoptosis of nucleus pulposus cells, and alleviated intervertebral disc degeneration in CS rats. These effects may be mediated by specifically regulating the SDF-1/CXCR4 signaling axis. Based on these findings, we conclude that Ns might serve as a promising therapy for the treatment of CS.


Asunto(s)
Apoptosis , Quimiocina CXCL12 , Modelos Animales de Enfermedad , Degeneración del Disco Intervertebral , Núcleo Pulposo , Ratas Sprague-Dawley , Receptores CXCR4 , Animales , Receptores CXCR4/metabolismo , Receptores CXCR4/genética , Quimiocina CXCL12/metabolismo , Apoptosis/efectos de los fármacos , Núcleo Pulposo/metabolismo , Núcleo Pulposo/efectos de los fármacos , Núcleo Pulposo/patología , Degeneración del Disco Intervertebral/metabolismo , Degeneración del Disco Intervertebral/patología , Degeneración del Disco Intervertebral/tratamiento farmacológico , Ratas , Masculino , Vértebras Cervicales , Transducción de Señal/efectos de los fármacos , Espondilosis/metabolismo , Espondilosis/patología
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