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1.
Opt Lett ; 49(7): 1812-1815, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38560871

RESUMO

To concurrently determine the thermophysical parameters of semi-transparent materials, a novel, to the best of our knowledge, integrated approach for concurrent measurement is proposed. In the measurement setup, a high-temperature radiation source and a beam reducer are employed to minimize the influence of background radiation. In order to differentiate between the transmitted and emitted radiation in the detection signal, the radiation signals from the radiation source are measured under four different conditions, enabling the calculation of transmissivity, emissivity, and reflectivity. The reliability and accuracy of the measurement method are validated by the thermophysical parameters of sapphire, and the results demonstrate a strong agreement between the measured data and previous findings. The combined uncertainties of transmissivity and emissivity for the sapphire at 753 K are estimated, highlighting the novel contribution of this method in investigating the thermophysical parameters of semi-transparent materials.

2.
Cell Rep ; 43(2): 113689, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38241149

RESUMO

As a primary target of severe acute respiratory syndrome coronavirus 2, lung exhibits heterogeneous histopathological changes following infection. However, comprehensive insight into their protein basis with spatial resolution remains deficient, which hinders further understanding of coronavirus disease 2019 (COVID-19)-related pulmonary injury. Here, we generate a region-resolved proteomic atlas of hallmark pathological pulmonary structures by integrating histological examination, laser microdissection, and ultrasensitive proteomics. Over 10,000 proteins are quantified across 71 post-mortem specimens. We identify a spectrum of pathway dysregulations in alveolar epithelium, bronchial epithelium, and blood vessels compared with non-COVID-19 controls, providing evidence for transitional-state pneumocyte hyperplasia. Additionally, our data reveal the region-specific enrichment of functional markers in bronchiole mucus plugs, pulmonary fibrosis, airspace inflammation, and alveolar type 2 cells, uncovering their distinctive features. Furthermore, we detect increased protein expression associated with viral entry and inflammatory response across multiple regions, suggesting potential therapeutic targets. Collectively, this study provides a distinct perspective for deciphering COVID-19-caused pulmonary dysfunction by spatial proteomics.


Assuntos
COVID-19 , Lesão Pulmonar , Humanos , Proteômica , SARS-CoV-2 , Células Epiteliais Alveolares
3.
Acad Radiol ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38057180

RESUMO

RATIONALE AND OBJECTIVES: To develop a monitoring model using radiomics analysis based on longitudinal B-mode ultrasound (BUS) and shear wave elastography (SWE) to early predict pathological response to neoadjuvant chemotherapy (NAC) in breast cancer patients. MATERIALS AND METHODS: In this prospective study, 112 breast cancer patients who received NAC between September 2016 and March 2022 were included. The BUS and SWE data of breast cancer were obtained prior to treatment as well as after two and four cycles of NAC. Radiomics features were extracted followed by measuring the changes in radiomics features compared to baseline after the second and fourth cycles of NAC (△R [C2], △R [C4]), respectively. The delta radiomics signatures were established using a support vector machine classifier. RESULTS: The area under receiver operating characteristic curve (AUC) values of △RBUS (C2) and △RBUS (C4) for predicting the response to NAC were 0.83 and 0.84, while those of △RSWE (C2) and △RSWE (C4) were 0.88 and 0.90, respectively. △RSWE exhibited significantly superior performance to △RBUS for predicting NAC response (Delong test, p < 0.01). No significant differences were observed in the performances between △R (C2) and △R (C4) based on BUS or SWE data. The longitudinal dual-modal ultrasound radiomics (LDUR) model had an excellent discrimination, good calibration and clinical usefulness, with the AUC, sensitivity and specificity of 0.97, 95.52% and 91.11%, respectively. CONCLUSION: The LDUR model achieved excellent performance in predicting the pathological response to chemotherapy during the early stages of NAC for breast cancer.

4.
Opt Express ; 31(20): 32684-32703, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859065

RESUMO

In this paper, what we believe to be, a new combined algorithm of artificial bee colony and slime mould algorithm (CABCSMA) and a differential evolution (DE) algorithm using target-to-best variation strategy are proposed to process the data based on Planck's radiation law and the mathematical model of reference temperature. The material model with 6 different emissivity trends is simulated. Simulation results show that the average relative error of CABCSMA algorithm is less than 0.68%, and the average calculation time is 0.44s. The average relative error of DE algorithm is less than 0.43%, and the average calculation time is only 0.06s. The two algorithms were applied to the temperature test of silicon carbide sample, tungsten material and rocket engine nozzle. The experimental results show that the relative error of silicon carbide experimental temperature is less than 0.41% and 0.28%, and the relative error of tungsten material experimental temperature is less than 0.31% and 0.3%. The relative errors of rocket engine nozzle temperature experiments are within 0.68% and 0.52%, respectively. The results show that these two algorithms are expected to be applied in practical measurement scenarios.

5.
Opt Express ; 31(13): 20905-20918, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37381203

RESUMO

The unknown emissivity still poses a significant challenge in the data processing of Multispectral radiation thermometry (MRT). In order to achieve global optimal solution with fast convergence speed and strong robustness, a systematic comparative analysis of particle swarm optimization (PSO) and simulated annealing (SA) algorithms in the application in MRT is presented in this paper. The simulations of six hypothetical emissivity models were compared, and the results indicate that the PSO algorithm is superior to the SA algorithm in accuracy, efficiency and stability. The measured data of the surface temperature of rocket motor nozzle is simulated by the PSO algorithm, the maximum absolute error and the maximum relative error are 16.27 K and 0.65%, and the calculation time is less than 0.3 s. The superior performance of the PSO algorithm indicates that it can be well used in data processing for accurate temperature measurement in MRT, and the method proposed in this paper can be extended to other multispectral systems and applied to various industrial processes under high temperature conditions.

6.
Acad Radiol ; 30 Suppl 2: S50-S61, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37270368

RESUMO

RATIONALE AND OBJECTIVES: To carry out radiomics analysis/deep convolutional neural network (CNN) based on B-mode ultrasound (BUS) and shear wave elastography (SWE) to predict response to neoadjuvant chemotherapy (NAC) in breast cancer patients. MATERIALS AND METHODS: In this prospective study, 255 breast cancer patients who received NAC between September 2016 and December 2021 were included. Radiomics models were designed using a support vector machine classifier based on US images obtained before treatment, including BUS and SWE. And CNN models also were developed using ResNet architecture. The final predictive model was developed by combining the dual-modal US and independently associated clinicopathologic characteristics. The predictive performances of the models were assessed with five-fold cross-validation. RESULTS: Pretreatment SWE performed better than BUS in predicting the response to NAC for breast cancer for both the CNN and radiomics models (P < 0.001). The predictive results of the CNN models were significantly better than the radiomics models, with AUCs of 0.72 versus 0.69 for BUS and 0.80 versus 0.77 for SWE, respectively (P = 0.003). The CNN model based on the dual-modal US and molecular data exhibited outstanding performance in predicting NAC response, with an accuracy of 83.60% ± 2.63%, a sensitivity of 87.76% ± 6.44%, and a specificity of 77.45% ± 4.38%. CONCLUSION: The pretreatment CNN model based on the dual-modal US and molecular data achieved excellent performance for predicting the response to chemotherapy in breast cancer. Therefore, this model has the potential to serve as a non-invasive objective biomarker to predict NAC response and aid clinicians with individual treatments.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Terapia Neoadjuvante , Estudos Prospectivos , Ultrassonografia/métodos , Estudos Retrospectivos
7.
Opt Express ; 30(20): 35381-35397, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36258491

RESUMO

The data processing in multispectral thermometry remains a huge challenge due to the unknown emissivity. In this article, a novel data processing model of multispectral thermometer is established by adding new constraints of emissivity on the basis of object function. The new two algorithms for model optimizing, Sequential Randomized Coordinate Shrinking (SRCS) and Multiple-Population Genetic (MPG), are introduced. The temperature and emissivity of two samples are calculated by MPG algorithm to prove the validity of the MPG algorithm in practical application. The experiments reveal that the relative error of temperature is within 0.4% with the average calculation time of 0.36 s. The method proposed in this article can realize the simultaneous estimation of temperature and emissivity without emissivity assumption model, which is expected to be applied to real-time measurement of temperature in industrial fields.

8.
Eur Radiol ; 32(10): 6830-6839, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35881185

RESUMO

OBJECTIVE: This study compared the performance between ultrasound (US)- and contrast-enhanced US (CEUS)-guided liver biopsies and evaluated the benefit of CEUS in percutaneous biopsy for focal liver lesions (FLLs). METHODS: We performed a retrospective study of 820 patients with FLLs, who underwent percutaneous liver biopsy in our center between 2017 and 2019. The patients were divided into two groups based on whether US (n = 362) or CEUS (n = 458) used before a biopsy. The two groups were compared based on specimen adequacy for pathological diagnosis and diagnostic accuracy of liver biopsy. Stratification analysis was performed based on lesion and protocol characteristics to provide detailed information for selecting the imaging guidance for biopsy. RESULTS: Compared with the US group, the CEUS group yielded more acceptable samples (97.6% vs. 99.4%, p < 0.05) and improved diagnostic accuracy (92.6% vs. 96.4%, p < 0.05), and achieved better sensitivity (92.5% vs. 96.2%, p < 0.05) for liver biopsies, especially in FLLs ≥ 5 cm, heterogeneous hypoechoic FLLs, or FLLs with an obscure boundary. The CEUS group showed significantly higher accuracy compared with the US group pertaining to single-puncture biopsies (100% vs. 92.7%, p < 0.05) or biopsies with punctures ≤ 2 (97.6% vs. 94.3%, p < 0.05). CONCLUSION: CEUS achieved an enhanced success rate for sampling and diagnostic accuracy of liver biopsies, especially in FLLs ≥ 5 cm, heterogeneous hypoechoic FLLs, or FLLs with an obscure boundary. CEUS can be used to decrease the number of punctures needed, which might increase the safety of liver biopsy. KEY POINTS: • CEUS can help confirm an adequate biopsy site, increasing the sampling success rate and diagnostic accuracy of the liver biopsy. • CEUS can be used to decrease the number of punctures needed to improve the safety of liver biopsy. • It is recommended to use CEUS guidance for liver biopsies, especially with FLLs ≥ 5 cm, heterogeneous hypoechoic FLLs, or FLLs with an obscure boundary.


Assuntos
Meios de Contraste , Neoplasias Hepáticas , Biópsia , Meios de Contraste/farmacologia , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia/métodos
9.
Plant Commun ; 2(6): 100230, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34778746

RESUMO

Genotyping platforms, as critical supports for genomics, genetics, and molecular breeding, have been well implemented at national institutions/universities in developed countries and multinational seed companies that possess high-throughput, automatic, large-scale, and shared facilities. In this study, we integrated an improved genotyping by target sequencing (GBTS) system with capture-in-solution (liquid chip) technology to develop a multiple single-nucleotide polymorphism (mSNP) approach in which mSNPs can be captured from a single amplicon. From one 40K maize mSNP panel, we developed three types of markers (40K mSNPs, 251K SNPs, and 690K haplotypes), and generated multiple panels with various marker densities (1K-40K mSNPs) by sequencing at different depths. Comparative genetic diversity analysis was performed with genic versus intergenic markers and di-allelic SNPs versus non-typical SNPs. Compared with the one-amplicon-one-SNP system, mSNPs and within-mSNP haplotypes are more powerful for genetic diversity detection, linkage disequilibrium decay analysis, and genome-wide association studies. The technologies, protocols, and application scenarios developed for maize in this study will serve as a model for the development of mSNP arrays and highly efficient GBTS systems in animals, plants, and microorganisms.


Assuntos
Embaralhamento de DNA/métodos , Genoma de Planta , Genótipo , Técnicas de Genotipagem/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Melhoramento Vegetal/métodos , Zea mays/genética , Produtos Agrícolas/genética , Variação Genética , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único
10.
Int Immunopharmacol ; 94: 107496, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33639565

RESUMO

OBJECTIVES: Cathepsin B (CTSB), nod-like receptor family pyrin domain-containing 3 (NLRP3), and caspase-1 play an important role in the development of Acute Pancreatitis (AP). Besides, the relationship between the proteins remains poorly understood. In addition, whereas previous studies have found caspase-1 activation in AP, pyroptosis, a caspase-1 induced cell death mode, has never been proposed and proved in AP. METHODS: We induced AP in mice by intraperitoneal injection of cerulein. Mice in the inhibitor group of CTSB were pretreated with injection of CA-074me, while mice in the inhibitor group of caspase-1 were of Ac-YVAD-CHO, 1 h earlier. We evaluated the inflammation of the pancreas and the detected expression of activated CTSB, NLRP3, ASC, caspase-1p20, IL-1ß and IL-18. TUNEL staining was used to detect acinar cell death. RESULTS: The inflammation of the pancreas in the two inhibitor groups was significantly reduced compared with that in the AP group. We observed that CA-074me not only inhibits CTSB, but also suppresses the expression and activity of NLRP3, ASC and caspase-1. We found that CA-074me further inhibits the downstream event of caspase-1, including pro-inflammatory cytokine secretion and pyroptosis. Whereas Ac-YVAD-CHO inhibited caspase-1 and decreased pro-inflammatory cytokine secretion and pyroptosis, it did not down-regulate the expression and activity ofCTSB, NLRP3 and ASC. CONCLUSION: The results indicate that CTSB may aggravate AP by activating the NLRP3 inflammasome and promoting Caspase-1-induced pyroptosis. These provide clues about the pathophysiological mechanisms of AP, shedding light on new ideas and potential targets for the prevention and treatment of AP.


Assuntos
Catepsina B/imunologia , Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Pancreatite/imunologia , Animais , Caspase 1/imunologia , Ceruletídeo , Interleucina-1beta/sangue , Masculino , Camundongos Endogâmicos C57BL , Pâncreas/imunologia , Pâncreas/patologia , Pancreatite/sangue , Pancreatite/induzido quimicamente , Pancreatite/patologia , Piroptose
11.
Cancer Cell Int ; 20: 463, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32982585

RESUMO

BACKGROUND: Emerging studies have disclosed long non-coding RNAs (lncRNAs) as pivotal modulators in the progression of prostate cancer (PCa). Current research planned to figure out the involvement of lncRNA nicotinamide nucleotide transhydrogenase antisense RNA 1 (NNT-AS1) in PCa. METHODS: RNA expression was examined using RT-qPCR in PCa cells. Functional assays assessed the viability, proliferation, apoptosis and migration of PCa cells. RNA pull down and luciferase reporter experiments detected the interplay between miRNA and lncRNA or mRNA. RESULTS: NNT-AS1 was apparently upregulated in PCa cells. NNT-AS1 deficiency abrogated PCa cell viability, proliferation and migration but promoted apoptosis. Besides, miR-496 could be sequestered by NNT-AS1 to elevate the expression of DNA damage inducible transcript 4 (DDIT4) in PCa. Rescue assays indicated that overexpressed DDIT4 or restrained miR-496 could reverse the influence of NNT-AS1 depletion on malignant processes in PCa cells. CONCLUSION: NNT-AS1 contributes to the malignant phenotypes of PCa cells through targeting miR-496 to boost DDIT4 expression.

12.
Biochem Biophys Res Commun ; 533(2): 209-214, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-32376009

RESUMO

A mild reaction for DNA-compatible, palladium promoted Suzuki-Miyaura cross-coupling reaction of potassium Boc-protected aminomethyltrifluoroborate with DNA-conjugated aryl bromides has been developed efficiently. This novel DNA encoded chemistry reaction proceeded well with a wide range of functional group tolerance, including aryl bromides and heteroaryl bromides. Further, the utility our DNA conjugated aminomethylated arene products is demonstrated by reaction with various types of reagents (including amide formation with carboxylic acids, alkylation with aldehydes, and carbamoylation with amines) as would be desired for the production of a DNA encoded library.


Assuntos
Boratos/química , Brometos/química , DNA/química , Hidrocarbonetos Aromáticos/química , Aminação , Boratos/síntese química , Brometos/síntese química , Catálise , Técnicas de Química Combinatória , DNA/síntese química , Halogenação , Hidrocarbonetos Aromáticos/síntese química , Metilação , Paládio/química , Potássio/química , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química
13.
Org Lett ; 22(11): 4146-4150, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32383596

RESUMO

We report a DNA-compatible copper-mediated efficient synthesis of 1,2,3-triazoles via a one-pot reaction of aryl borates with TMS-N3 followed by a click cycloaddition reaction. Employing the binuclear macrocyclic nanocatalyst Cu(II)-ß-cyclodextrin, the reactions were performed under mild conditions with high conversions and wide functional group tolerance. We also demonstrate the reaction application toward a one-pot DNA-compatible intramolecular macrocyclization. Our optimized reaction protocol results in no significant DNA damage as judged by qPCR analysis and Sanger sequencing data.


Assuntos
Alcinos/química , Azidas/química , Boratos/química , Cobre/química , DNA/química , Triazóis/síntese química , Química Click , Reação de Cicloadição , Estrutura Molecular , Triazóis/química
14.
Artigo em Inglês | MEDLINE | ID: mdl-22956974

RESUMO

The root of Actinidia valvata dunn has been widely used in the treatment of hepatocellular carcinoma (HCC), proved to be beneficial for a longer and better life in China. In present work, total saponin from root of Actinidia valvata Dunn (TSAVD) was extracted, and its effects on hepatoma H22-based mouse in vivo were observed. Primarily transplanted hypodermal hepatoma H22-based mice were used to observe TSAVD effect on tumor growth. The microvessel density (MVD), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) are characterized factors of angiogenesis, which were compared between TSAVD-treated and control groups. Antimetastasis effect on experimental pulmonary metastasis hepatoma mice was also observed in the study. The results demonstrated that TSAVD can effectively inhibit HCC growth and metastasis in vivo, inhibit the formation of microvessel, downregulate expressions of VEGF and bFGF, and retrain angiogenesis of hepatoma 22 which could be one of the reasons.

15.
J Org Chem ; 74(10): 3930-2, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19382764

RESUMO

The first total synthesis of the 14-membered natural macrocyclic bislactone 4-keto-clonostachydiol, along with its enantiomer, has been accomplished in 13 steps with overall yields of 8.4% and 8.0%, respectively. The absolute configuration of 4-keto-clonostachydiol 1 has been revised as (5S,10S,13S).


Assuntos
Lactonas/síntese química , Compostos de Epóxi/química , Lactonas/química , Estereoisomerismo , Especificidade por Substrato
16.
J Org Chem ; 74(7): 2743-9, 2009 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-19323573

RESUMO

An efficient total synthesis of (-)-bitungolide F (6) in 17 steps and 20.1% yield is described herein. Key steps involve a Myers asymmetric alkylation to introduce the C6 methyl with proper stereochemistry, a Claisen-like cyclization to construct the alpha,beta-unsaturated delta-lactone and a Julia-Kocienski olefination to assemble the conjugated diene moiety.


Assuntos
Alcenos/síntese química , Pironas/síntese química , Álcoois/síntese química , Álcoois/química , Alcenos/química , Ciclização , Iodetos/síntese química , Iodetos/química , Estrutura Molecular , Pironas/química
17.
Org Lett ; 10(9): 1855-8, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18393520

RESUMO

An efficient acid-promoted domino Friedel-Crafts (FC) acylation/alkylation reaction has been developed for the construction of the core 6,5,6-ABC tricyclic skeleton of taiwaniaquinoids. The formal total syntheses of diterpenoids (+/-)-taiwaniaquinol B and (+/-)-dichroanone based on this strategy have been achieved.


Assuntos
Diterpenos/síntese química , Acilação , Alquilação , Diterpenos/química , Preparações de Plantas/química
18.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 7): o1187, 2008 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-21202829

RESUMO

The mol-ecules of the title compound, C(22)H(17)N, are linked by weak inter-actions, among which the most prominent are C-H⋯π inter-actions. The dihedral angles between the phenyl rings and the quinoline ring system are 43.3 (3) and 21.4 (3)°. The title product resulted from a three-component reaction of benzaldehyde, 1-ethynylbenzene and p-toluidine via C-H activation of 1-ethynylbenzene catalyzed by CuI in the ionic liquid 1-butyl-3-methyl-imidazolium hexa-fluoro-phosphate.

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