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1.
Biochem Biophys Res Commun ; 696: 149526, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38241812

RESUMO

PURPOSE: To investigated the role of estrogen receptor-1 (ER-1) in maintaining homeostasis in ocular surface. METHODS: ER-1-knockout (ER-1KO) mice were studied at 4 months of age. The ocular surface was examined using a slit lamp. Histological alterations in the meibomian gland (MG) and lacrimal gland (LG) were observed with H&E staining. Protein levels of P-ERK, peroxisome proliferator-activated receptor gamma (PPAR-γ), p-NFκB-P65, IL-1ß, aquaporin 5 (AQP-5), fatty acid-binding protein 5 (Fabp5) and K10 were determined by immunofluorescence and Western blotting. Gene expressions of APO-F, APO-E, K10, ELOVL4, PPAR-γ, SCD-1, and SREBP1 were quantified by qPCR. Conjunctival (CJ) goblet cell alterations were detected by PAS staining. Lipid metabolism in MG and LG was assessed using LipidTox. Apoptosis in MG and LG was analyzed through the TUNEL assay. RESULTS: Both male and female ER-1KO mice demonstrated increased corneal fluorescence staining scores. MG showed abnormal lipid metabolism and ductal dilation. LG displayed lipid deposition and reduced AQP-5 expression. CJ experienced goblet cell loss. MG, LG exhibited signs of inflammation and apoptosis. CONCLUSION: ER1 is pivotal for ocular surface homeostasis in both genders of mice. ER1 deficiency induces inflammation and lipid deposition to MG and LG, culminating in dry eye-like manifestations on the ocular surface.


Assuntos
Síndromes do Olho Seco , Aparelho Lacrimal , Receptores de Estrogênio , Animais , Feminino , Masculino , Camundongos , Síndromes do Olho Seco/genética , Síndromes do Olho Seco/metabolismo , Síndromes do Olho Seco/patologia , Inflamação/patologia , Aparelho Lacrimal/metabolismo , Aparelho Lacrimal/patologia , Glândulas Tarsais/metabolismo , Glândulas Tarsais/patologia , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Lágrimas/metabolismo , Receptores de Estrogênio/metabolismo
2.
Sensors (Basel) ; 23(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37430772

RESUMO

Distributed structure health monitoring has been a hot research topic in recent years, and optic fiber sensors are largely developed for the advantages of high sensitivity, better spatial resolution, and small sensor size. However, the limitation of fibers in installation and reliability has become one of the major drawbacks of this technology. This paper presents a fiber optic sensing textile and a new installation method inside bridge girders to address those shortcomings in fiber sensing systems. The sensing textile was utilized to monitor strain distribution in the Grist Mill Bridge located in Maine based on Brillouin Optical Time Domain Analysis (BOTDA). A modified slider was developed to increase the efficiency of installation in the confined bridge girders. The bridge girder's strain response was successfully recorded by the sensing textile during the loading tests that involved four trucks on the bridge. The sensing textile demonstrated the capability to differentiate separated loading locations. These results demonstrate a new way of installing fiber optic sensors and the potential applications of fiber optic sensing textiles in structural health monitoring.

3.
J Appl Clin Med Phys ; 21(1): 191-196, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31729812

RESUMO

PURPOSE: This technical note aims to investigate the dosimetric impact of stray radiation on the Common Control Unit (CCU) of the IBA Blue Phantom2 and the measured beam data. METHODS: Three CCUs of the same model were used for the study. The primary test CCU was placed at five distances from the radiation beam central axis. At each distance, a set of depth dose and beam profiles for two open and two wedge fields were measured. The field sizes were 10 × 10 cm2 and 30 × 30 cm2 for the open fields, and 30 × 30 cm2 and 15 × 15 cm2 for the 30° and 60° wedges, respectively. The other two CCUs were used to cross check the data of the primary CCU. Assuming the effect of stray radiation on the data measured at the farthest reachable distance 4.5 m is negligible, the dosimetric impact of stray radiation on the CCU and consequently on the measured data can be extracted for analysis by comparing it with those measured at shorter distances. RESULTS: The results of three CCUs were consistent. The dosimetric impact of stray radiation was greater for lower energies at larger field sizes. For open fields, the data variation was up to 4.5% for depth dose curves and 7.1% for beam profiles. For wedge fields, the data variation was up to 9.3% for depth dose curves and 10.6% for beam profiles. Moreover, for wedge field profiles in the wedge direction, they became flatter as the CCU was placed closer to the primary radiation beam, manifesting smaller wedge angles. CONCLUSION: The stray radiation added a uniform background noise on all measured data. The magnitude of the noise is inversely proportional to the square of the distance of the CCU to the primary radiation beam, approximately following the inverse square law.


Assuntos
Modelos Teóricos , Aceleradores de Partículas/instrumentação , Imagens de Fantasmas , Espalhamento de Radiação , Humanos , Doses de Radiação
4.
J Appl Clin Med Phys ; 15(5): 4713, 2014 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-25207561

RESUMO

In this study, we have characterized the efficiency of an Elekta linac in the delivery of gated radiotherapy. We have explored techniques to reduce the beam-on delay and to improve the delivery efficiency, and have investigated the impact of frequent beam interruptions on the dosimetric accuracy of gated deliveries. A newly available gating interface was installed on an Elekta Synergy. Gating signals were generated using a surface mapping system in conjunction with a respiratory motion phantom. A series of gated deliveries were performed using volumetric modulated arc therapy (VMAT) treatment plans previously generated for lung cancer patients treated with stereotactic body radiotherapy. Baseline values were determined for the delivery times. The machine was then tuned in an effort to minimize beam-on delays and improve delivery efficiency. After that process was completed, the dosimetric accuracy of the gated deliveries was evaluated by comparing the measured and the planned coronal dose distributions using gamma index analyses. Comparison of the gated and the non-gated deliveries were also performed. The results demonstrated that, with the optimal machine settings, the average beam-on delay was reduced to less than 0.22 s. High dosimetric accuracy was demonstrated with gamma index passing rates no lower than 99.0% for all tests (3%/3 mm criteria). Consequently, Elekta linacs can provide a practical solution for gated VMAT treatments with high dosimetric accuracy and only a moderate increase in the overall delivery time.


Assuntos
Neoplasias Pulmonares/radioterapia , Aceleradores de Partículas/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Alta Energia/instrumentação , Espirometria/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Dosagem Radioterapêutica , Eficiência Biológica Relativa , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Int J Mol Sci ; 15(2): 2695-711, 2014 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-24549173

RESUMO

The aim of this study was to prepare nanosized Tripterygium wilfordii multi-glycoside (GTW) powders by the supercritical antisolvent precipitation process (SAS), and to evaluate the anti-inflammatory effects. Ethanol was used as solvent and carbon dioxide was used as an antisolvent. The effects of process parameters such as precipitation pressure (15-35 MPa), precipitation temperature (45-65 °C), drug solution flow rates (3-7 mL/min) and drug concentrations (10-30 mg/mL) were investigated. The nanospheres obtained with mean diameters ranged from 77.5 to 131.8 nm. The processed and unprocessed GTW were characterized by scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy and thermal gravimetric analysis. The present study was designed to investigate the beneficial effect of the GTW nanoparticles on adjuvant-induced arthritis in albino rats. The processed and unprocessed GTW were tested against Freund's complete adjuvant-induced arthritis in rats. Blood samples were collected for the estimation of interleukins (IL-1α, IL-1ß) and tumor necrosis factor-α (TNF-α). It was concluded that physicochemical properties and anti-inflammatory activity of GTW nanoparticles could be improved by physical modification, such as particle size reduction using supercritical antisolvent (SAS) process. Further, SAS process was a powerful methodology for improving the physicochemical properties and anti-inflammatory activity of GTW.


Assuntos
Anti-Inflamatórios/química , Glicosídeos/química , Nanopartículas/química , Tripterygium/metabolismo , Animais , Anti-Inflamatórios/uso terapêutico , Artrite/induzido quimicamente , Artrite/tratamento farmacológico , Dióxido de Carbono/química , Cromatografia com Fluido Supercrítico , Feminino , Glicosídeos/uso terapêutico , Interleucina-1alfa/sangue , Interleucina-1beta/sangue , Tamanho da Partícula , Ratos , Ratos Wistar , Líquido Sinovial/metabolismo , Temperatura , Fator de Necrose Tumoral alfa/sangue
6.
Hortic Res ; 11(3): uhae007, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38487543

RESUMO

Traditional agriculture is gradually being combined with artificial intelligence technology. High-performance fruit detection technology is an important basic technology in the practical application of modern smart orchards and has great application value. At this stage, fruit detection models need to rely on a large number of labeled datasets to support the training and learning of detection models, resulting in higher manual labeling costs. Our previous work uses a generative adversarial network to translate the source domain to the target fruit images. Thus, automatic labeling is performed on the actual dataset in the target domain. However, the method still does not achieve satisfactory results for translating fruits with significant shape variance. Therefore, this study proposes an improved fruit automatic labeling method, EasyDAM_V4, which introduces the Across-CycleGAN fruit translation model to achieve spanning translation between phenotypic features such as fruit shape, texture, and color to reduce domain differences effectively. We validated the proposed method using pear fruit as the source domain and three fruits with large phenotypic differences, namely pitaya, eggplant, and cucumber, as the target domain. The results show that the EasyDAM_V4 method achieves substantial cross-fruit shape translation, and the average accuracy of labeling reached 87.8, 87.0, and 80.7% for the three types of target domain datasets, respectively. Therefore, this research method can improve the applicability of the automatic labeling process even if significant shape variance exists between the source and target domain.

7.
Plant Phenomics ; 5: 0067, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37519937

RESUMO

Although deep learning-based fruit detection techniques are becoming popular, they require a large number of labeled datasets to support model training. Moreover, the manual labeling process is time-consuming and labor-intensive. We previously implemented a generative adversarial network-based method to reduce labeling costs. However, it does not consider fitness among more species. Methods of selecting the most suitable source domain dataset based on the fruit datasets of the target domain remain to be investigated. Moreover, current automatic labeling technology still requires manual labeling of the source domain dataset and cannot completely eliminate manual processes. Therefore, an improved EasyDAM_V3 model was proposed in this study as an automatic labeling method for additional classes of fruit. This study proposes both an optimal source domain establishment method based on a multidimensional spatial feature model to select the most suitable source domain, and a high-volume dataset construction method based on transparent background fruit image translation by constructing a knowledge graph of orchard scene hierarchy component synthesis rules. The EasyDAM_V3 model can automatically obtain fruit label information from the dataset, thereby eliminating manual labeling. To test the proposed method, pear was used as the selected optimal source domain, followed by orange, apple, and tomato as the target domain datasets. The results showed that the average precision of annotation reached 90.94%, 89.78%, and 90.84% for the target datasets, respectively. The EasyDAM_V3 model can obtain the optimal source domain in automatic labeling tasks, thus eliminating the manual labeling process and reducing associated costs and labor.

8.
Biochem Pharmacol ; 218: 115901, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38084678

RESUMO

The gastrin-releasing peptide receptor (GRPR) binds to ligands such as gastrin-releasing peptide (GRP) and plays a variety of biological roles. In this study, we investigated the therapeutic effect of a novel gastrin-releasing peptide receptor antagonist RH-1402 in hyperuricemia-induced kidney fibrosis and its underlying mechanisms. We conducted enzyme linked immunosorbent assay (ELISA) and immunohistochemical analyses and found that proGRP and GRPR expression levels were significantly increased in patients with hyperuricemic nephropathy (HN) and HN mice. GRPR knockdown significantly attenuated inflammatory and fibrotic responses in adenosine-treated human proximal tubule epithelial cells. GRPR knockout or GRPR conditional knockout in renal tubular epithelial cells significantly alleviated the decline in renal function and fibrosis in HN mice in vivo. RNA-seq and String database analysis revealed that GRP/GRPR promoted HN by suppressing the ABCG2/PDZK1 and increasing TGF-ß/Smad3 levels by activating the NF-κB pathway. Overexpression of GRPR increased TGF-ß/Smad3 levels, where as it reduced ABCG2/PDZK1 levels in adenosine-treated HK2 cells, which was reversed by the NF-κB inhibitor. Furthermore, we evaluated the therapeutic effects of the novel GRPR inhibitor RH-1402 on hyperuricaemia-induced renal injury and evaluated the inflammatory and fibrosis responses in vivo and in vitro. Pre-treatment with RH-1402 attenuated hyperuricaemia-induced renal injury, restored renal function, and suppressed renal inflammation and fibrosis. Taken together, GRPR enhances hyperuricaemia-induced tubular injury, inflammation, and renal fibrosis via ABCG2-dependent mechanisms and may serve as a promising therapeutic target for HN treatment.


Assuntos
Hiperuricemia , Nefropatias , Nefrite , Animais , Humanos , Camundongos , Adenosina , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Fibrose , Hiperuricemia/tratamento farmacológico , Inflamação , Nefropatias/etiologia , Proteínas de Neoplasias/metabolismo , Nefrite/etiologia , NF-kappa B/metabolismo , Receptores da Bombesina/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
9.
J Appl Clin Med Phys ; 13(6): 3838, 2012 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-23149777

RESUMO

The aim of this study is to develop an automated method to objectively compare motion artifacts in two four-dimensional computed tomography (4D CT) image sets, and identify the one that would appear to human observers with fewer or smaller artifacts. Our proposed method is based on the difference of the normalized correlation coefficients between edge slices at couch transitions, which we hypothesize may be a suitable metric to identify motion artifacts. We evaluated our method using ten pairs of 4D CT image sets that showed subtle differences in artifacts between images in a pair, which were identifiable by human observers. One set of 4D CT images was sorted using breathing traces in which our clinically implemented 4D CT sorting software miscalculated the respiratory phase, which expectedly led to artifacts in the images. The other set of images consisted of the same images; however, these were sorted using the same breathing traces but with corrected phases. Next we calculated the normalized correlation coefficients between edge slices at all couch transitions for all respiratory phases in both image sets to evaluate for motion artifacts. For nine image set pairs, our method identified the 4D CT sets sorted using the breathing traces with the corrected respiratory phase to result in images with fewer or smaller artifacts, whereas for one image pair, no difference was noted. Two observers independently assessed the accuracy of our method. Both observers identified 9 image sets that were sorted using the breathing traces with corrected respiratory phase as having fewer or smaller artifacts. In summary, using the 4D CT data of ten pairs of 4D CT image sets, we have demonstrated proof of principle that our method is able to replicate the results of two human observers in identifying the image set with fewer or smaller artifacts.


Assuntos
Artefatos , Tomografia Computadorizada Quadridimensional , Movimento (Física) , Interpretação de Imagem Radiográfica Assistida por Computador , Mecânica Respiratória , Algoritmos , Automação , Humanos , Variações Dependentes do Observador
10.
J Radiosurg SBRT ; 8(1): 47-54, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35387403

RESUMO

Two automated treatment planning techniques were evaluated for multiple brain metastases using a single isocenter. One technique is knowledge-based planning (KBP) using a stereotactic radiosurgery (SRS) model in Eclipse treatment planning system (TPS); and the other is the Multiple Brain Mets (MBM) SRS technique in Brainlab Elements TPS. Eighteen plans each with 3-10 lesions were used for the study. Plan evaluation metrics included the planning target volume (PTV) coverage, conformity index (CI), total monitor units (MUs), plan optimization time, brain V12 Gy, V8 Gy, and V5 Gy. Both the KBP and MBM planning techniques produced comparable plans to the manually generated clinical plans in terms of PTV coverage and CI. For irregularly shaped lesions, the KBP plans provided more conformal dose distribution to the PTV than the MBM plans. The KBP plans took significantly longer time to plan but have fewer MUs than the MBM plans. The MBM plans spared normal brain tissues better than the KBP plans in terms of V5 Gy.

11.
Artigo em Inglês | MEDLINE | ID: mdl-21969841

RESUMO

In order to understand the possible role of globin genes in fish salinity adaptation, we report the molecular characterization and expression of all four subunits of haemoglobin, and their response to salinity challenge in flounder. The entire open reading frames of α1-globin and α2-globin genes were 432 and 435 bp long, respectively, whereas the ß1-globin and ß2-globin genes were both 447 bp. Although the head kidney (pronephros) is the predicted major site of haematopoiesis, real-time PCR revealed that expression of α-globin and ß-globin in kidney (mesonephros) was 1.5 times higher than in head kidney. Notably, the α1-globin and ß1-globin mRNA expression was higher than α2-globin and ß2-globin in kidney. Expression levels of all four globin subunits were higher in freshwater- (FW-) than in seawater- (SW-)adapted fish kidney. If globins do play a role in salinity adaptation, this is likely to be more important in combating the hemodilution faced by fish in FW than the dehydration and salt loading which occur in SW.

12.
J Appl Clin Med Phys ; 11(4): 3262, 2010 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-21081883

RESUMO

A respiratory training system based on audiovisual biofeedback has been implemented at our institution. It is intended to improve patients' respiratory regularity during four-dimensional (4D) computed tomography (CT) image acquisition. The purpose is to help eliminate the artifacts in 4D-CT images caused by irregular breathing, as well as improve delivery efficiency during treatment, where respiratory irregularity is a concern. This article describes the commissioning and quality assurance (QA) procedures developed for this peripheral respiratory training system, the Stanford Respiratory Training (START) system. Using the Varian real-time position management system for the respiratory signal input, the START software was commissioned and able to acquire sample respiratory traces, create a patient-specific guiding waveform, and generate audiovisual signals for improving respiratory regularity. Routine QA tests that include hardware maintenance, visual guiding-waveform creation, auditory sounds synchronization, and feedback assessment, have been developed for the START system. The QA procedures developed here for the START system could be easily adapted to other respiratory training systems based on audiovisual biofeedback.


Assuntos
Biorretroalimentação Psicológica , Garantia da Qualidade dos Cuidados de Saúde , Mecânica Respiratória/fisiologia , Tomografia Computadorizada por Raios X/métodos , Gravação em Vídeo/métodos , Algoritmos , Feminino , Humanos , Imageamento Tridimensional , Intensificação de Imagem Radiográfica , Interpretação de Imagem Radiográfica Assistida por Computador , Software
13.
Opt Express ; 14(6): 2289-99, 2006 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-19503566

RESUMO

We report a novel hemispherical micro-cavity that is comprised of a planar integrated semiconductor distributed Bragg reflector (DBR) mirror, and an external, concave micro-mirror having a radius of curvature 50 microm. The integrated DBR mirror containing quantum dots (QD), is designed to locate the QDs at an antinode of the field in order to maximize the interaction between the QD and cavity. The concave micro-mirror, with high-reflectivity over a large solid-angle, creates a diffraction-limited (sub-micron) mode-waist at the planar mirror, leading to a large coupling constant between the cavity mode and QD. The half-monolithic design gives more spatial and spectral tuning abilities, relatively to fully monolithic structures. This unique micro-cavity design will potentially enable us to both reach the cavity quantum electrodynamics (QED) strong coupling regime and realize the deterministic generation of single photons on demand.

14.
Opt Express ; 13(24): 9660-5, 2005 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-19503171

RESUMO

We calculate the integrated-pulse quantum efficiency of single-photon sources in the cavity quantum electrodynamics (QED) strong-coupling regime. An analytical expression for the quantum efficiency is obtained in the Weisskopf-Wigner approximation. Optimal conditions for a high quantum efficiency and a temporally localized photon emission rate are examined. We show the condition under which the earlier result of Law and Kimble [J. Mod. Opt. 44, 2067 (1997)] can be used as the first approximation to our result.

15.
Springerplus ; 2(1): 289, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23853756

RESUMO

Embryonic development and morphological characteristics of Japanese devil stinger Inimicus japonicus during early life stage were investigated. Larvae were hatched out 50 h after fertilization at temperature 21°C. Total length of the newly hatched larva was 4.03 mm, the mouth of the larva opened at 3 days after hatching (DAH), and the yolk sac of the larva disappeared at 5 DAH. After hatching, the pectoral fin first developed, then the tail fin, dorsal fin, anal fin and pelvic fin continuously developed, and all fins formed completely at 15 DAH. The metamorphosis was complete at 25 DAH, and the body color and habit of the metamorphosed individuals were different from the larvae. At 30 DAH, the morphology and habit of the juveniles were the same to adults. In order to determine the suitable salinity for larviculture of I. japonicus, salinity tolerance at different early developmental stages was compared in terms of the survival activity index (SAI) and mean survival time (MST). The results indicated that salinity tolerance varied with development stages. The optimum salinity range for newly hatched larvae was 10-25‰. Larvae showed low tolerance to low salinity (5‰) before the mouth opened, and the suitable salinities for the larvae with open mouth, yolk-sac larvae, post yolk-sac larvae were 10-15‰. The flexion larvae showed a wider salinity tolerance with range of 5-20‰. After metamorphosis, the juveniles showed a preferable adaptability of salinities of 15-20‰. The SAI and MST of individuals at various stages under different salinity conditions were positively correlated.

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