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1.
Opt Express ; 32(2): 2271-2280, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38297761

RESUMEN

In this article, we report a Si/Ge waveguide phototransistor with high responsivity and low dark current under low bias voltages, due to an engineered electric field distribution. The photodetector consists of n-i-p-i-n doping regions and shows a responsivity of 606 A/W at 1 V bias, and 1032 A/W at 2.8V bias with an input optical power of -50 dBm, and dark current of 4 µA and 42 µA respectively. This is achieved by placing two p+-doped regions in the silicon slab region beneath the Ge epitaxial layer. A measured small signal -3 dB bandwidth of 1.5 GHz with a -80 dBc/Hz phase noise response at 1 KHz frequency offset were demonstrated experimentally.

2.
J Endod ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38848947

RESUMEN

INTRODUCTION: In dental clinical practice, cone-beam computed tomography (CBCT) is commonly used to assist practitioners to recognize the complex morphology of root canal systems; however, because of its resolution limitations, certain small anatomical structures still cannot be accurately recognized on CBCT. The purpose of this study was to perform image super-resolution (SR) processing on CBCT images of extracted human teeth with the help of a deep learning model, and to compare the differences among CBCT, super-resolution computed tomography (SRCT), and micro-computed tomography (Micro-CT) images through three-dimensional reconstruction. METHODS: The deep learning model (Basicvsr++) was selected and modified. The dataset consisted of 171 extracted teeth that met inclusion criteria, with 40 maxillary first molars as the training set and 40 maxillary first molars as well as 91 teeth from other tooth positions as the external test set. The corresponding CBCT, SRCT, and Micro-CT images of each tooth in test sets were reconstructed using Mimics Research 17.0, and the root canal recognition rates in the 3 groups were recorded. The following parameters were measured: volume of hard tissue (V1), volume of pulp chamber and root canal system (V2), length of visible root canals under orifice (VL-X, where X represents the specific root canal), and intersection angle between coronal axis of canal and long axis of tooth (∠X, where X represents the specific root canal). Data were statistically analyzed between CBCT and SRCT images using paired sample t-test and Wilcoxon test analysis, with the measurement from Micro-CT images as the gold standard. RESULTS: Images from all tested teeth were successfully processed with the SR program. In 4-canal maxillary first molar, identification of MB2 was 72% (18/25) in CBCT group, 92% (23/25) in SRCT group, and 100% (25/25) in Micro-CT group. The difference of hard tissue volume between SRCT and Micro-CT was significantly smaller than that between CBCT and Micro-CT in all tested teeth except 4-canal mandibular first molar (P < .05). Similar results were obtained in volume of pulp chamber and root canal system in all tested teeth (P < .05). As for length of visible root canals under orifice, the difference between SRCT and Micro-CT was significantly smaller than that between CBCT and Micro-CT (P < .05) in most root canals. CONCLUSIONS: The deep learning model developed in this study helps to optimize the root canal morphology of extracted teeth in CBCT. And it may be helpful for the identification of MB2 in the maxillary first molar.

3.
Aquat Toxicol ; 273: 107024, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39003955

RESUMEN

As environmental awareness increases, the use of recyclable plastics has risen. However, it is currently unclear whether recycled microplastics (MPs) pose a lesser or greater environmental risk than pristine MPs. Cadmium (Cd), known for its toxicity to most organisms, can bind with MPs and accumulate in sediments. Few studies have explored the environmental risks posed by the coexistence of recycled MPs and pristine MPs with Cd to rooted macrophytes. We investigated the effects of recycled PVC MPs (R-PVC-MPs) and pristine PVC MPs (PVC-MPs) on Vallisneria natans in the presence and absence of Cd. Results showed that at moderate and high Cd levels, R-PVC-MPs reduced plant Cd enrichment. Despite this, the fresh weight of V. natans exposed to R-PVC-MPs was significantly lower than those exposed to PVC-MPs. Furthermore, R-PVC-MPs had more negative impacts on the physiological traits of V. natans than PVC-MPs, as chlorophyll was significantly reduced across all Cd levels. At high Cd levels, both R-PVC-MPs and PVC-MPs caused significantly high oxidative stress, with no significant differences observed. The PCoA plot showed that different MPs cause noticeable variations within the same Cd concentration. The trait network diagrams illustrated strong interactions among traits, with R-PVC-MPs showing the highest complexity. Lower average degree and decreased edge density indicate that traits of plants with R-PVC-MPs addition are more independent of each other. Our findings suggest that recycled PVC MPs pose a greater environmental risk than pristine PVC MPs, offering reference for assessing the risks of recycled plastics in freshwater ecosystems.


Asunto(s)
Cadmio , Microplásticos , Cloruro de Polivinilo , Reciclaje , Contaminantes Químicos del Agua , Cadmio/toxicidad , Cloruro de Polivinilo/toxicidad , Microplásticos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Plásticos/toxicidad , Estrés Oxidativo/efectos de los fármacos , Clorofila/metabolismo
4.
Chemosphere ; 362: 142646, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38897324

RESUMEN

Widespread lead (Pb) contamination of agricultural soils is a global issue stemming from human activities. The remediation of Pb-contaminated soils used for agricultural purposes is critically important to safeguard food crop safety. Despite the modulating effects of sulfur (S) on plant responses to toxic heavy metals, the ecological, physiological, and molecular mechanisms driving such modulation in the Pb hyperaccumulator Arabis alpina L. remain unclear. Here, we investigated the effects of five S concentrations (0, 50, 100, 150, and 200 mg kg-1) on A. alpina grown in Pb-contaminated soil from a lead-zinc mining area. Under S50 (i.e., 50 mg kg-1) and S100 treatments, the Pb concentration in both shoots and roots of A. alpina significantly decreased compared to the control (S0). Specifically, the S50 treatment significantly enhanced Pb accumulation, plant biomass, and plant height, indicating that low S applications facilitate Pb accumulation from the soil and alleviate Pb toxicity. Additionally, S50, S100, and S150 treatments significantly improved photosynthetic rate, stomatal conductance, and intercellular CO2 concentration in A. alpina. Transcriptomic analysis showed that S50 and S100 treatments increased the expression of the LHCA, LHCB, psa, and psb genes, which had a significant impact on photosynthetic efficiency. S50 and S100 boosted glutathione (GSH) levels in A. alpina roots, and the increased expression of GST gene enhanced tolerance to environmental stress. In summary, these results suggest that an appropriate supply of S (S50 and S100) not only alleviates Pb toxicity by enhancing plant biomass, height, photosynthetic features, and sulfur metabolites but also stimulates Pb accumulation in the hyperaccumulator A. alpina. Our study elucidated the specific concentrations of sulfur that optimally enhance both Pb accumulation and stress tolerance in the hyperaccumulator A. alpina, providing novel insights into the practical application of sulfur in phytoremediation strategies and advancing our understanding of the underlying molecular mechanisms.


Asunto(s)
Arabis , Biodegradación Ambiental , Plomo , Contaminantes del Suelo , Azufre , Plomo/toxicidad , Plomo/metabolismo , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/metabolismo , Arabis/metabolismo , Arabis/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Suelo/química , Raíces de Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Minería
5.
Cell Biosci ; 14(1): 31, 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38461242

RESUMEN

AIM: To understand how liver sinusoidal endothelial cells (LSECs) respond to nonalcoholic steatohepatitis (NASH). METHODS: We profiled single-LSEC from livers of control and MCD-fed mice. The functions of C-Kit+-LSECs were determined using coculture and bone marrow transplantation (BMT) methods. RESULTS: Three special clusters of single-LSEC were differentiated. C-Kit+-LSECs of cluster 0, Msr1+-LSECs of cluster 1 and Bmp4+Selp+-VECs of cluster 2 were revealed, and these cells with diverse ectopic expressions of genes participated in regulation of endothelial, fibrosis and lipid metabolism in NASH. The number of C-Kit+-primary LSECs isolated from MCD mice was lower than control mice. Immunofluorescence co-staining of CD31 and C-KIT showed C-Kit+-LSECs located in hepatic sinusoid were also reduced in NASH patients and MCD mice, compared to AIH patients and control mice respectively. Interestingly, lipotoxic hepatocytes/HSCs cocultured with C-Kit+-LSECs or the livers of MCD mice receipting of C-Kit+-BMCs (bone marrow cells) showed less steatosis, inflammation and fibrosis, higher expression of prolipolytic FXR and PPAR-α, lower expression of TNF-α and α-SMA. Furthermore, coculturing or BMT of C-Kit+-endothelial derived cells could increase the levels of hepatic mitochondrial LC3B, decrease the degree of mitochondrial damage and ROS production through activating Pink1-mediated mitophagy pathway in NASH. CONCLUSIONS: Hence, a novel transcriptomic view of LSECs was revealed to have heterogeneity and complexity in NASH. Importantly, a cluster of C-Kit+-LSECs was confirmed to recovery Pink1-related mitophagy and NASH progression.

6.
Asian J Pharm Sci ; 19(1): 100890, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38419760

RESUMEN

Melittin, a classical antimicrobial peptide, is a highly potent antitumor agent. However, its significant toxicity seriously hampers its application in tumor therapy. In this study, we developed novel melittin analogs with pH-responsive, cell-penetrating and membrane-lytic activities by replacing arginine and lysine with histidine. After conjugation with camptothecin (CPT), CPT-AAM-1 and CPT-AAM-2 were capable of killing tumor cells by releasing CPT at low concentrations and disrupting cell membranes at high concentrations under acidic conditions. Notably, we found that the C-terminus of the melittin analogs was more suitable for drug conjugation than the N-terminus. CPT-AAM-1 significantly suppressed melanoma growth in vivo with relatively low toxicity. Collectively, the present study demonstrates that the development of antitumor drugs based on pH-responsive antimicrobial peptide-drug conjugates is a promising strategy.

7.
Front Microbiol ; 15: 1385992, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952443

RESUMEN

Introduction: Weeds are significant factors that detrimentally affect crop health and hinder optimal herbage yield. Rhizosphere microorganisms play crucial roles in plant growth, development, and nutrient uptake. Therefore, research focusing on weed control through the lens of microorganisms has emerged as a prominent area of study. The oil-producing fungus Mortierella, which is known for its numerous agricultural benefits, has garnered significant attention in recent years. Methods: In this study, we conducted inoculation experiments in a controlled artificial culture climate chamber to investigate the effects of differential hormones and differentially expressed genes in the stems and leaves of Digitaria sanguinalis using Liquid Chromatography Tandem Mass Spectrometry and RNA-seq techniques, respectively. Additionally, Pearson's correlation analysis was used to establish correlations between differential hormones and growth indicators of Digitaria sanguinalis. Results and discussion: The results demonstrated that inoculation with Mortierella sp. MXBP304 effectively suppressed aboveground biomass and plant height in Digitaria sanguinalis. Furthermore, there was significant upregulation and downregulation in the expression of genes involved in the synthesis and metabolism of phenylalanine and L-phenylalanine. Conversely, the expression of genes related to tryptophan, L-tryptophan, and indole was significantly downregulated. The addition of Mortierella sp. MXBP304 can influence the gene expression associated with phenylalanine and tryptophan synthesis and metabolism during Digitaria sanguinalis growth, subsequently reducing the relative contents of phenylalanine and tryptophan, thereby directly inhibiting Digitaria sanguinalis growth.

8.
Emerg Microbes Infect ; 13(1): 2377599, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38973388

RESUMEN

African swine fever virus (ASFV) is the causative agent of African swine fever (ASF), a highly contagious disease that can kill up to 100% of domestic pigs and wild boars. It has been shown that the pigs inoculated with some ASF vaccine candidates display more severe clinical signs and die earlier than do pigs not immunized. We hypothesize that antibody-dependent enhancement (ADE) of ASFV infection may be caused by the presence of some unidentified antibodies. In this study, we found that the ASFV-encoded structural protein A137R (pA137R) can be recognized by the anti-ASFV positive sera, indicating that the anti-pA137R antibodies are induced in the ASFV-infected pigs. Interestingly, our results demonstrated that the anti-pA137R antibodies produced in rabbits or pigs enhanced viral replication of different ASFV strains in primary porcine alveolar macrophages (PAMs), the target cells of ASFV. Mechanistic investigations revealed that anti-pA137R antibodies were able to promote the attachment of ASFV to PAMs and two types of Fc gamma receptors (FcγRs), FcγRII and FcγRIII, mediated the ADE of ASFV infection. Taken together, anti-pA137R antibodies are able to drive ASFV ADE in PAMs. These findings shed new light on the roles of anti-ASFV antibodies and have implications for the pathophysiology of the disease and the development of ASF vaccines.


Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Anticuerpos Antivirales , Acrecentamiento Dependiente de Anticuerpo , Macrófagos Alveolares , Receptores de IgG , Animales , Virus de la Fiebre Porcina Africana/inmunología , Macrófagos Alveolares/inmunología , Macrófagos Alveolares/virología , Porcinos , Fiebre Porcina Africana/virología , Fiebre Porcina Africana/inmunología , Anticuerpos Antivirales/inmunología , Receptores de IgG/inmunología , Replicación Viral , Conejos
9.
Breast ; 76: 103762, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38924994

RESUMEN

BACKGROUND: Male breast cancer (MBC) is a rare disease. Although several large-scale studies have investigated MBC patients in other countries, the features of MBC patients in China have not been fully explored. This study aims to explore the features of Chinese MBC patients comprehensively. METHODS: We retrospectively collected data of MBC patients from 36 centers in China. Overall survival (OS) was evaluated by the Kaplan-Meier method, log-rank test, and Cox regression analyses. Multivariate Cox analyses were used to identify independent prognostic factors of the patients. RESULTS: In total, 1119 patients were included. The mean age at diagnosis was 60.9 years, and a significant extension over time was observed (P < 0.001). The majority of the patients (89.1 %) received mastectomy. Sentinel lymph node biopsy was performed in 7.8 % of the patients diagnosed in 2009 or earlier, and this percentage increased significantly to 38.8 % in 2020 or later (P < 0.001). The five-year OS rate for the population was 85.5 % [95 % confidence interval (CI), 82.8 %-88.4 %]. Multivariate Cox analysis identified taxane-based [T-based, hazard ratio (HR) = 0.32, 95 % CI, 0.13 to 0.78, P = 0.012] and anthracycline plus taxane-based (A + T-based, HR = 0.47, 95 % CI, 0.23 to 0.96, P = 0.037) regimens as independent protective factors for OS. However, the anthracycline-based regimen showed no significance in outcome (P = 0.175). CONCLUSION: As the most extensive MBC study in China, we described the characteristics, treatment and prognosis of Chinese MBC population comprehensively. T-based and A + T-based regimens were protective factors for OS in these patients. More research is required for this population.


Asunto(s)
Neoplasias de la Mama Masculina , Mastectomía , Biopsia del Ganglio Linfático Centinela , Humanos , Neoplasias de la Mama Masculina/patología , Neoplasias de la Mama Masculina/mortalidad , Neoplasias de la Mama Masculina/terapia , Neoplasias de la Mama Masculina/epidemiología , Masculino , Persona de Mediana Edad , China/epidemiología , Estudios Retrospectivos , Mastectomía/estadística & datos numéricos , Anciano , Biopsia del Ganglio Linfático Centinela/estadística & datos numéricos , Adulto , Pronóstico , Modelos de Riesgos Proporcionales , Estimación de Kaplan-Meier , Taxoides/uso terapéutico , Tasa de Supervivencia , Hidrocarburos Aromáticos con Puentes/uso terapéutico , Antraciclinas/uso terapéutico , Anciano de 80 o más Años
10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 40(1): 111-122, 2022 Jan 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-38597002

RESUMEN

OBJECTIVES: This study aims to establish a minimally invasive treatment using a customized digital template and a miniaturized bur for pulp canal obliteration (PCO). METHODS: Cone-beam computed tomography (CBCT) and digital oral scans of patients diagnosed with PCO in anterior teeth were obtained. Root canal morphology was reconstructed to accurately show the location, length, and direction of obliteration. A digital template was designed and fabricated using visual design software and 3D printing technology and used as guide for the miniaturized bur and drill sleeve during calcified tissue removal. A conventional root canal treatment was performed after the lumen of the root canal was reached. RESULTS: In both cases, the planned access cavity and glide paths were successfully established. In case 1, the deviated angle of the access cavity was 1.37°±0.07°, the deviation at the bottom of the miniaturized bur was 0.08-0.81 mm, the deviation at the tip of the bur was 0.05-1.13 mm, and difference in substance loss was 0.84-4.25 mm³. In case 2, the deviated angle of the access cavity was 3.09° ± 0.12°, the deviation at the bottom of the bur was 0.09-0.68 mm, the deviation at the tip of the bur was 0.29-0.66 mm, and the difference in substance loss was 0.55-3.79 mm3. CONCLUSIONS: Micro-guided endodontics is a novel approach for localizing and negotiating obliterated root canals and guarantees long-term prognosis without requiring excessive hard tissue removal.

11.
Int. j. morphol ; 34(2): 465-470, June 2016. ilus
Artículo en Inglés | LILACS | ID: lil-787022

RESUMEN

The objective of this study was to construct three-dimensional (3D) images of premolars to measure the length, surface area and volume of crown and root and to analyze the mathematical relation among crown-to-root ratios in terms of length, surface area and volume. Twenty-five premolars were scanned using micro-computed tomography (micro CT) in vitro to build 3D models. The long axis and enamelo-cemental junction of each tooth were determined with the help of Geomagic Studio software, and the length, surface and volume of crown and root were measured. The crown-to-root ratios in terms of length, surface and volume were calculated and the relationship among length, surface area and volume of crown and root as well their ratios were analyzed using SPSS software. The interrelationship among crown length (x), surface area (y) and volume (z) could be expressed as z= -808.2 0+ 124.80x +3.35y -5.59x2-0.14xy+3.47y 2*10-4 (R2 = 0.99) and that of root length (x1), surface area (y1) and volume (z1), as z1= -207.50 +13.87x1+1.75y1 + 5.03x12*10-2-8.05x 1y1 *10-2+ 2.58*10-3y12 (R2 = 0.93) . The correlation among crown-to-root ratio in length(x2), crown-to-root ratio in surface area (y2) and crown-to-root ratio in volume (z2) could be expressed in z2= -4.48*10-2 -1.25x2*10-2+1.20y2 + 3.29x22-5.05x2y2 + 2.00y22 (R2 = 0.96). The length, surface area and volume of crown and root of premolars share a close relationship, while, a definite mathematical relation could be observed amongst their ratios. Crown to root ratio in terms of length, surface and volume, may provide a novel multi-criterion method for evaluating tooth function.


El objetivo de este estudio fue construir imágenes tridimensionales (3D) de los dientes premolares para medir la longitud, superficie y volumen de la corona y raíz, junto con analizar la relación matemática entre las proporciones de la corona a la raíz en términos de longitud, superficie y volumen. Veinticinco premolares fueron escaneados mediante microtomografía computadorizada (microTC) in vitro para construir modelos en 3D. Con el software Geomagic se determinaron el eje y la unión amelo-cementaria de cada diente, y se midieron la longitud, superficie y volumen de la corona y la raíz de los dientes premolares. Con el programa SPSS se calcularon y analizaron las proporciones de la corona a la raíz en términos de longitud, superficie y volumen y la relación entre la longitud, superficie y volumen de la corona y de la raíz. La interrelación entre la longitud de la corona (x), superficie (y) y el volumen (z) puede ser expresado como z= -808,2 0+ 124,80x + 3,35y -5,59x2-0,14xy + 3.47y2*10-4 (R2= 0,99) y la de longitud de la raíz (x1), área de superficie (y1) y el volumen (z1), como z1= -207,50 + 13.87x1 + 1.75y1 + 5.03x12 * 10-2-8.05x1y1 * 10-2 + 2,58 * 10-3y12 (R2= 0,93). La correlación entre la relación de corona a raíz en longitud (x2), la relación corona a raíz en superficie (y2) y la relación corona a raíz en volumen (Z2) podría expresarse en z2 = -4,48 * 10-2 * 10-2 -1.25x2 + 1.20y2 3.29x22-5.05x2y2 + 2.00y22 (R2= 0,96). La longitud, superficie y volumen de la corona y la raíz de los dientes premolares comparten una estrecha relación, mientras que, una relación matemática definida se pudo observar entre sus proporciones. La relación entre la corona y raíz en términos de longitud, superficie y volumen, puede proporcionar un nuevo método multi-criterio para evaluar la función de los dientes.


Asunto(s)
Humanos , Diente Premolar/anatomía & histología , Corona del Diente/anatomía & histología , Raíz del Diente/anatomía & histología , Imagenología Tridimensional , Proyectos Piloto
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