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1.
Phys Chem Chem Phys ; 25(8): 6164-6174, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36752176

RESUMO

Phonon thermal transport is a key feature for the operation of thermoelectric materials, but it is challenging to accurately calculate the thermal conductivity of materials with strong anharmonicity or large cells. In this work, a deep neural network potential (NNP) is developed using a dataset based on density functional theory (DFT) and applied to describe the lattice dynamics of Sb2Te3 and Bi2Te3/Sb2Te3 superlattices. The lattice thermal conductivities of Sb2Te3 are first predicted using equilibrium molecular dynamics (EMD) simulations combined with an NNP and the results match well with experimental values. Then, through further exploration of weighted phase spaces and the Grüneisen parameter, we find that there is a stronger anharmonicity in the out-of-plane direction in Sb2Te3, which is the reason why the thermal conductivities are overestimated more in the out-of-plane direction than in the in-plane direction by solving the phonon Boltzmann transport equation (BTE) with only three-phonon scattering processes being considered. More importantly, the lattice thermal conductivities of Bi2Te3/Sb2Te3 superlattices with different periods are accurately predicted using non-equilibrium molecular dynamics (NEMD) simulations together with an NNP, which serves as a good example to explore the thermal transport physics of superlattices using a deep neural network potential.

2.
Phys Chem Chem Phys ; 25(22): 15422-15432, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37248727

RESUMO

Element doping is a prominent method for reducing the lattice thermal conductivity and optimizing the thermoelectric performance of materials in the thermoelectric field. However, determination of the thermal conductivity of element-doped systems is a challenging task, especially when the elements are randomly doped. In this work, a first-principles based deep neural network potential (NNP) is developed to investigate the lattice thermal transport properties of Cr-doped Sb2Te3 using molecular dynamics simulations. Compared with pure Sb2Te3, the thermal conductivity of orderly Cr-doped Sb2Te3 with Cr atoms locating at specific atomic layer positions decreases slightly in the in-plane direction, but sharply in the out-of-plane direction. The decrease of the low frequency phonon density of states and the enhancement of phonon scattering near 2.5 THz are the primary reasons for the decrease in the thermal conductivity of Cr-doped Sb2Te3, while the decrease of phonon velocity due to band flattening is the reason for the sharp decrease of thermal conductivity in the out-of-plane direction. Moreover, the thermal conductivities of randomly Cr-doped Sb2Te3 with different Cr concentrations are also investigated using the NNP. It is found that the thermal conductivities in both the in-plane and out-of-plane directions are reduced by 76% and 80%, respectively, for Sb36Cr36Te108. Furthermore, the influence of different Cr dopant arrays on the thermal conductivity of Sb2Te3 is also predicted using the NNP. Our work provides a good example for predicting the thermal conductivity of element-doped systems using the NNP combined with molecular dynamics simulations.

3.
J Comput Assist Tomogr ; 47(3): 355-360, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37184996

RESUMO

OBJECTIVE: Our study aimed to investigate the role of quantitative parameters derived from dual-energy computed tomography (DECT) in discriminating metastatic from nonmetastatic lymph nodes in hepatocellular carcinoma (HCC). METHODS: Forty-two patients (34 males; mean age, 53.7 years) with HCC underwent unenhanced computed tomography scans and triple-phase DECT scans of the upper abdomen. A total of 72 suspected lymph nodes were resected, including 43 nonmetastatic and 29 metastatic lymph nodes. The maximum short-axis diameter of the lymph nodes, iodine concentration, normalized iodine concentration (NIC), and slope of the spectral curve were analyzed for the HCC primary lesions and the suspected lymph nodes. Lymph node metastasis was confirmed by pathologic examination. RESULTS: A maximum short-axis diameter of >10 mm had a sensitivity and a specificity of 75.9% (22/29) and 53.5% (23/43) in diagnosing metastatic lymph nodes. The iodine concentration, NIC, and slope of the spectral curve of the nonmetastatic lymph nodes were significantly higher than those of the primary HCC lesions and the metastatic lymph nodes (all P < 0.05). Among all the analyzed spectral parameters, the NIC in the arterial phase had the highest sensitivity and specificity of 88.4% and 86.2% in diagnosing metastatic lymph nodes. CONCLUSIONS: The arterial phase NIC of DECT has superior diagnostic performance than the traditional lymph node size in diagnosing metastatic lymph nodes in HCC.


Assuntos
Carcinoma Hepatocelular , Iodo , Neoplasias Hepáticas , Masculino , Humanos , Pessoa de Meia-Idade , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Tomografia Computadorizada por Raios X/métodos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia
4.
BMC Gastroenterol ; 21(1): 427, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34772340

RESUMO

BACKGROUND: In rare cases, intrahepatic cholangiocarcinoma can present as a pyogenic liver abscess and are often misdiagnosed. This study aimed to analyze the imaging features of intrahepatic cholangiocarcinoma mimicking a pyogenic liver abscess. METHODS: The clinical data and imaging results of eight patients with pathologically confirmed intrahepatic cholangiocarcinoma mimicking a liver abscess were retrospectively collected. RESULTS: The mean age was 58 years with a range of 46-68 years. Fever and leukocytosis were present in six patients. All the eight lesions were a single mass. Air-liquid levels were present in two patients. Only one patient showed hepatic lobar atrophy and hepatic capsule retraction. The double target sign of liver abscess was not noticed in the CT/MRI images of all eight patients. The inner wall of the lesion was rough and irregular, with multiple dot/patchy and wall nodule enhancements. The abscess wall and the marginal parenchyma were supplied by the hepatic artery in four patients, and the intralesional arteries were rough and disrupted. Bile duct dilatation was seen adjacent to the lesion. In seven patients, diffusion-weighted images showed irregular patchy restricted diffusion in the marginal parenchyma of the necrotic area in addition to the prominent restricted diffusion in the necrotic area. Two patients with cholangiolithiasis showed patchy slight CT hypodensity, slight T1 hypointensity, slight T2 hyperintensity, and patchy delayed enhancement. Multiple lymph nodes enlargement in the hepatic hilar area and the retroperitoneal space were seen in five patients. CONCLUSION: Intrahepatic cholangiocarcinoma mimicking a pyogenic liver abscess have unique imaging features and require careful image examination to avoid misdiagnosis.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Abscesso Hepático Piogênico , Idoso , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
Heliyon ; 10(3): e24336, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38318072

RESUMO

Background: Qing-Jin-Hua-Tan decoction (QJHTD) is a classic traditional Chinese medicine (TCM) prescription that first appeared in the ancient book Yi-Xue-Tong-Zhi. QJHTD has shown effectiveness for treating chronic obstructive pulmonary disease (COPD), although its mechanisms of action are still perplexing. The molecular mechanisms underlying the curative effects of QJHTD on COPD is worth exploring. Methods: In vitro antiapoptotic and antiinflammatory activities of QJHTD were evaluated using cell viability, proliferation, apoptosis rate, and expression of IL-1ß and TNF-α in BEAS-2B and RAW264.7 cells challenged with cigarette smoke (CS) extract (CSE) and lipopolysaccharide (LPS). In vivo therapeutic activities of QJHTD were evaluated using respiratory parameters (peak inspiratory flow (PIFb) and peak expiratory flow (PEFb) values), histopathology (mean linear intercept, MLI), and proinflammatory cytokine (IL-1ß and TNF-α) and cleaved caspase-3 (c-Casp3) levels in the lung tissue of CS-LPS-exposed BALB/c mice. Network pharmacology-based prediction, transcriptomic analysis, and metabolic profiling were employed to investigate the signaling molecules and metabolites pertinent to the anti-COPD action of QJHTD. Results: Increased cell viability and proliferation with decreased apoptosis rate and proinflammatory cytokine expression were noted after QJHTD intervention. QJHTD administration elevated PEFb and PIFb values, reduced MLI, and inhibited IL-1ß, TNF-α, and c-Casp3 expression in vivo. Integrated network pharmacology-transcriptomics revealed that suppressing inflammatory signals (IL-1ß, IL-6, TNF, IκB-NF-κB, TLR, and MAPK) and apoptosis contributed to the anti-COPD property of QJHTD. Metabolomic profiling unveiled prominent roles for the suppression of apoptosis and sphingolipid (SL) metabolism and the promotion of choline (Ch) metabolism in the anti-COPD effect of QJHTD. Integrative transcriptomics-metabolomics unraveled the correlation between SL metabolism and apoptosis. In silico molecular docking revealed that acacetin, as an active compound in QJHTD, could bind with high affinity to MEK1, MEK2, ERK1, ERK2, Bcl2, NF-κB, and alCDase target proteins. Conclusion: The therapeutic effect of QJHTD on COPD is dependent on regulating inflammatory signals and apoptosis-directed SL metabolism. These findings provide deeper insights into the molecular mechanism of action of QJHTD against COPD and justify its theoretical promise in novel pharmacotherapy for this multifactorial disease.

6.
Curr Med Imaging ; 20: 1-7, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38389349

RESUMO

BACKGROUND: Preoperative T-staging is essential for planning optimal treatment and care for colorectal cancer (CRC). OBJECTIVE: To evaluate the accuracy of Dual-energy CT (DECT) in preoperative T-staging of CRC. METHODS: The clinical data and DECT images of 37 patients with 39 CRC lesions were retrospectively analyzed. The performance of the DECT quantitative parameters in CRC T-staging was evaluated. Postoperative pathologic results were used as a gold standard. Receiver operating characteristic curves were used to assess the diagnostic efficacy of DECT parameters. P < 0.05 was deemed significant. RESULTS: The overall accuracy of T-staging by DECT was 76.9%. The DECT parameters were significantly different between the T3 pericolic fat stranding, T4a pericolic fat stranding, and normal pericolic fat stranding. Arterial phase λHU had the best diagnostic performance with a cut-off value of ≥0.967, resulting in a 70.6% sensitivity and a 100% specificity in differentiating between T3 and T4a stages of CRC. CONCLUSION: DECT has high accuracy in the T-staging of CRC. Arterial phase λHU has the best diagnostic performance in differentiating between T3 and T4a stages of CRC.


Assuntos
Neoplasias Colorretais , Tomografia Computadorizada por Raios X , Humanos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Estadiamento de Neoplasias , Curva ROC , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/patologia
7.
World J Gastrointest Oncol ; 16(4): 1309-1318, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38660663

RESUMO

BACKGROUND: Despite continuous changes in treatment methods, the survival rate for advanced hepatocellular carcinoma (HCC) patients remains low, highlighting the importance of diagnostic methods for HCC. AIM: To explore the efficacy of texture analysis based on multi-parametric magnetic resonance (MR) imaging (MRI) in predicting microvascular invasion (MVI) in preoperative HCC. METHODS: This study included 105 patients with pathologically confirmed HCC, categorized into MVI-positive and MVI-negative groups. We employed Original Data Analysis, Principal Component Analysis, Linear Discriminant Analysis (LDA), and Non-LDA (NDA) for texture analysis using multi-parametric MR images to predict preoperative MVI. The effectiveness of texture analysis was determined using the B11 program of the MaZda4.6 software, with results expressed as the misjudgment rate (MCR). RESULTS: Texture analysis using multi-parametric MRI, particularly the MI + PA + F dimensionality reduction method combined with NDA discrimination, demonstrated the most effective prediction of MVI in HCC. Prediction accuracy in the pulse and equilibrium phases was 83.81%. MCRs for the combination of T2-weighted imaging (T2WI), arterial phase, portal venous phase, and equilibrium phase were 22.86%, 16.19%, 20.95%, and 20.95%, respectively. The area under the curve for predicting MVI positivity was 0.844, with a sensitivity of 77.19% and specificity of 91.67%. CONCLUSION: Texture analysis of arterial phase images demonstrated superior predictive efficacy for MVI in HCC compared to T2WI, portal venous, and equilibrium phases. This study provides an objective, non-invasive method for preoperative prediction of MVI, offering a theoretical foundation for the selection of clinical therapy.

8.
Int Med Case Rep J ; 17: 487-495, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784139

RESUMO

Objective: We report a case of Carmi Syndrome in a neonate. Aim: To share our lessons in diagnosis of the case of Carmi Syndrome. Case Report: Carmi Syndrome is an extremely rare autosomal recessive genetic disorder characterized the coexistence of pyloric atresia and junctional epidermolysis bullosa, and with aplasia cutis congenita in approximately 28% patients. In this case, a full-term male neonate was born to a G4P2+1L1 multipara through cesarean section delivery in hospital in a non-consanguineous marriage with 4000mL of II°meconium-stained amniotic fluid. He was found extensive skin loss over lower legs and other parts, with scattered blisters and bilateral microtia. Plain abdominal X-ray revealed a large gastric air bubble with no gas distally. The mother had an intrauterine fetal loss previously for reasons unknown. The dermatologist diagnosed the newborn with Bart Syndrome, while the pediatric surgeon diagnosed congenital pyloric atresia(CPA). The parents refused further treatment and the neonate passed away about 30 hours after birth. Outcome: The neonate passed away about 30 hours after birth. Conclusion: Lessons from this case:①.Rule out Carmi Syndrome in patients with PA, and differentiate Bart syndrome and Carmi Syndrome in patients with abnormal skin manifestations. ②. For rare and/or severe diseases, multidisciplinary teams(MDTs) should be establish. ③. Genetic counseling and prenatal diagnosis are necessary prior to subsequent childbearings. ④.Termination of pregnancy might be contemplated if certain indicators are revealed.

9.
Plant Divers ; 45(1): 69-79, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36876309

RESUMO

Tropical lotus (Nelumbo) is an important and unique ecological type of lotus germplasm. Understanding the genetic relationship and diversity of the tropical lotus is necessary for its sustainable conservation and utilization. Using 42 EST-SSR (expressed sequence tag-simple sequence repeats) and 30 SRAP (sequence-related amplified polymorphism) markers, we assessed the genetic diversity and inferred the ancestry of representative tropical lotus from Thailand and Vietnam. In total, 164 and 41 polymorphic bands were detected in 69 accessions by 36 EST-SSR and seven SRAP makers, respectively. Higher genetic diversity was revealed in Thai lotus than in Vietnamese lotus. A Neighbor-Joining tree of five main clusters was constructed using combined EST-SSR and SRAP markers. Cluster I included 17 accessions of Thai lotus; cluster II contained three Thai accessions and 11 accessions from southern Vietnam; and cluster III was constituted by 13 accessions of seed lotus. Consistent with the results from the Neighbor-Joining tree, the genetic structure analysis showed that the genetic background of most Thai and Vietnamese lotus was pure, as artificial breeding has been rare in both countries. Furthermore, these analyses indicate that Thai and Vietnamese lotus germplasms belong to two different gene pools or populations. Most lotus accessions are genetically related to geographical distribution patterns in Thailand or Vietnam. Our findings showed that the origin or genetic relationships of some unidentified lotus sources can be evaluated by comparing morphological characteristics and the data of molecular markers. In addition, these findings provide reliable information for the targeted conservation of tropical lotus and parent selection in breeding novel cultivars of lotus.

10.
Chin Med ; 17(1): 136, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36482376

RESUMO

BACKGROUND: Taxillus chinensis (DC.) Danser (T. chinensis), known as "Sangjisheng" in Chinese, is a member of the family Loranthaceae, with the traditional functions of "dispelling wind dampness, strengthening bones and muscles, and preventing miscarriage". Since Eastern Han dynasty, it has been used for the treatment of rheumatoid arthritis, arthralgia, threatened abortion, and hypertension. Nowadays, T. chinensis is included in the 2020 Edition of the Chinese Pharmacopoeia as Taxilli Herba. The purpose of this review is to summarize the latest research on T. chinensis in recent years, and make critical comments, so as to provide reference for the clinical application and modern research of T. chinensis. MAIN BODY: In this review, we summarize the botany, traditional uses, and research advances in the phytochemistry and pharmacological effects of T. chinensis. Its toxicity has also been discussed. The published literature on current pharmacological and toxicological data has also been assessed. To date, approximately 110 compounds, including flavonoids, phenolic acids, phenylpropanoids, tannins, glycosides, amino acids, and nucleosides, have been identified in T. chinensis. Flavonoids are considered the most vital bioactive ingredients in T. chinensis. Pharmacological studies have demonstrated that T. chinensis possesses anti-inflammatory, antioxidant, anticancer, antimicrobial, antiviral, diuretic, antihypertensive, antihyperglycemic, and other properties. CONCLUSION: Currently, research on T. chinensis is in the preliminary stages, and further research is required to understand the active compounds present and mechanisms of action. We hope that this comprehensive review of T. chinensis will serve as a background for further research.

11.
Pharmaceuticals (Basel) ; 15(10)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36297316

RESUMO

Thrombocytopenia is one of the most common complications of cancer therapy. Until now, there are still no satisfactory medications to treat chemotherapy and radiation-induced thrombocytopenia (CIT and RIT, respectively). Caulis Polygoni Multiflori (CPM), one of the most commonly used Chinese herbs, has been well documented to nourish blood for tranquilizing the mind and treating anemia, suggesting its beneficial effect on hematopoiesis. However, it is unknown whether CPM can accelerate megakaryopoiesis and thrombopoiesis. Here, we employ a UHPLC Q-Exactive HF-X mass spectrometer (UHPLC QE HF-X MS) to identify 11 ingredients in CPM. Then, in vitro experiments showed that CPM significantly increased megakaryocyte (MK) differentiation and maturation but did not affect apoptosis and lactate dehydrogenase (LDH) release of K562 and Meg-01 cells. More importantly, animal experiments verified that CPM treatment markedly accelerated platelet recovery, megakaryopoiesis and thrombopoiesis in RIT mice without hepatic and renal toxicities in vivo. Finally, RNA-sequencing (RNA-seq) and western blot were used to determine that CPM increased the expression of proteins related to PI3K/Akt and MEK/ERK (MAPK) signaling pathways. On the contrary, blocking PI3K/Akt and MEK/ERK signaling pathways with their specific inhibitors suppressed MK differentiation induced by CPM. In conclusion, for the first time, our study demonstrates that CPM may be a promised thrombopoietic agent and provide an experimental basis for expanding clinical use.

13.
Phys Rev E ; 98(1-1): 012319, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30110844

RESUMO

Identification and quantification of the structural dissimilarities between complex networks is a very important and challenging problem in network science. A simple and efficient way to quantify network differences remains unexplored. Although the methods for network comparison based on the probability distribution of a network descriptor have been shown to be effective for specific purposes, the information they provide is often limited or incomplete. In order to overcome the defect of the methods, here we use the communicability between two nodes to define the communicability sequence entropy of networks, and on the basis of this entropy measure, we propose a Jensen-Shannon divergence of two networks which can be used as natural distance measure between complex networks. By the extensive experiments, we find that the measure can accurately quantify the structural dissimilarities between synthetic networks. Most importantly, the measure can be able to identify the critical percolation probability of the random network in the evolution process, and it can also effectively guide us to choose a more suitable model to simulate real systems.

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