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1.
Horm Metab Res ; 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38354749

RESUMO

Interleukin-18 (IL-18) is a proinflammatory cytokine that primarily stimulates the Th1 immune response. IL-18 exhibits anticancer activity and has been evaluated in clinical trials as a potential cancer treatment. However, evidence suggests that it may also facilitate the development and progression of some cancers. So far, the impact of IL-18 on papillary thyroid cancer (PTC) has not been investigated. In this study, we found that the expression of IL-18 was significantly increased in PTC compared to normal thyroid tissue. Elevated IL-18 expression was closely associated with lymphovascular invasion and lymph node metastases. Furthermore, compared to PTC patients with no nodal metastasis, serum IL-18 levels were slightly increased in patients with 1-4 nodal metastases and significantly elevated in patients with 5 or more nodal metastases. The pro-metastatic effect of IL-18 may be attributed to the simultaneous increase in the expression of S100A10, a known factor that is linked to nodal metastasis in PTC. In addition, the activation of several pathways, such as the intestinal immune network for lgA production and Staphylococcus aureus infection, may be involved in the metastasis process. Taken together, IL-18 may trigger pro-metastatic activity in PTC. Therefore, suppressing the function of IL-18 rather than enhancing it appears to be a reasonable strategy for treating aggressive PTC.

2.
Psychiatr Q ; 95(2): 233-252, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38639873

RESUMO

This study investigated the healthcare utilization and medical expenditure of type 2 diabetes mellitus (T2DM) patients with generalized anxiety disorder (GAD) and identified the associated factors. The healthcare utilization and expenditure of T2DM patients with (case group) and without (control group) GAD between 2002 and 2013 were examined using the population-based Taiwan National Health Insurance Research Database. Healthcare utilization included outpatient visits and hospitalization; health expenditure included outpatient, inpatient, and total medical expenditure. Moreover, nonpsychiatric healthcare utilization and medical expenditure were distinguished from total healthcare utilization and medical expenditure. The average healthcare utilization, including outpatient visits and hospitalization, was significantly higher for the case group than for the control group (total and nonpsychiatric). The results regarding differences in average outpatient expenditure (total and nonpsychiatric), inpatient expenditure (total and nonpsychiatric), and total expenditure (total and nonpsychiatric) between the case and control groups are inconsistent. Sex, age, income, comorbidities/complications, and the diabetes mellitus complication severity index were significantly associated with outpatient visits, medical expenditure, and hospitalization in the case group (total and nonpsychiatric). Greater knowledge of factors affecting healthcare utilization and expenditure in comorbid individuals may help healthcare providers intervene to improve patient management and possibly reduce the healthcare burden in the future.


Assuntos
Transtornos de Ansiedade , Comorbidade , Diabetes Mellitus Tipo 2 , Gastos em Saúde , Hospitalização , Aceitação pelo Paciente de Cuidados de Saúde , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/terapia , Diabetes Mellitus Tipo 2/economia , Masculino , Feminino , Pessoa de Meia-Idade , Transtornos de Ansiedade/epidemiologia , Adulto , Taiwan/epidemiologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Idoso , Hospitalização/estatística & dados numéricos , Gastos em Saúde/estatística & dados numéricos , Assistência Ambulatorial/estatística & dados numéricos , Assistência Ambulatorial/economia
3.
Opt Express ; 31(6): 9236-9250, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37157497

RESUMO

We study the enhanced sensing of optomechanically induced nonlinearity (OMIN) in a cavity-waveguide coupled system. The Hamiltonian of the system is anti-PT symmetric, with the two involved cavities being dissipatively coupled via the waveguide. The anti-PT symmetry may break down when a weak waveguide-mediated coherent coupling is introduced. However, we find a strong bistable response of the cavity intensity to the OMIN near the cavity resonance, benefiting from linewidth suppression caused by the vacuum induced coherence. The joint effect of optical bistability and the linewidth suppression is inaccessible by the anti-PT symmetric system involving only dissipative coupling. Due to that, the sensitivity measured by an enhancement factor is greatly enhanced by two orders of magnitude compared to that for the anti-PT symmetric model. Moreover, the enhancement factor shows resistance to a reasonably large cavity decay and robustness to fluctuations in the cavity-waveguide detuning. Based on the integrated optomechanical cavity-waveguide systems, the scheme can be used for sensing different physical quantities related to the single-photon coupling strength and has potential applications in high-precision measurements with systems involving Kerr-type nonlinearity.

4.
Chaos ; 33(7)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37459222

RESUMO

Chimera states in spatiotemporal dynamical systems have been investigated in physical, chemical, and biological systems, while how the system is steering toward different final destinies upon spatially localized perturbation is still unknown. Through a systematic numerical analysis of the evolution of the spatiotemporal patterns of multi-chimera states, we uncover a critical behavior of the system in transient time toward either chimera or synchronization as the final stable state. We measure the critical values and the transient time of chimeras with different numbers of clusters. Then, based on an adequate verification, we fit and analyze the distribution of the transient time, which obeys power-law variation process with the increase in perturbation strengths. Moreover, the comparison between different clusters exhibits an interesting phenomenon, thus we find that the critical value of odd and even clusters will alternatively converge into a certain value from two sides, respectively, implying that this critical behavior can be modeled and enabling the articulation of a phenomenological model.

5.
J Nurs Scholarsh ; 55(1): 291-303, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36056586

RESUMO

PURPOSE: The use of technology-assisted interventions in dementia care contributes to increased communication, reduced burden on the caregivers, improved health outcomes, and improved expense management. Technology-assisted interventions can be provided remotely to monitor, improve, and enable home care, benefiting the health of both patients and caregivers. Despite increasing use, the effectiveness of technology-assisted interventions for dementia care remains uncertain, with studies reporting inconclusive findings subject to interpretation. Therefore, the current study investigated the available evidence to explore the efficacy of technology-assisted interventions for people with dementia. DESIGN: Systematic review and meta-analysis. METHODS: The study was preregistered with the PROSPERO international prospective register of systematic reviews using a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-guided protocol. The primary search was conducted in eight databases from database inception to January 29, 2022. Using a random-effects model, the standardized mean differences (SMDs) with 95% confidence intervals (CIs) were synthesized to obtain pooled effect sizes (using Stata 16.0). The updated Cochrane Risk of Bias 2 tool (RoB-2) was used to evaluate the methodological quality of the studies. FINDINGS: A pooled analysis of 12 trials, including 584 people with dementia, showed more improvement associated with technology-assisted interventions compared with standard care, including in the domains of cognitive function (SMD = 0.39; 95% CI: 0.14 to 0.64; p < 0.001) and depression (SMD = -0.75; 95% CI: -1.33 to -0.17; p = 0.01). However, no significant effects were observed for activities of daily living (ADL) or quality of life. CONCLUSION: Technology-assisted interventions appear to improve cognitive function and reduce depression in people with dementia compared with standard care. CLINICAL RELEVANCE: This study may be used to demonstrate that interventions incorporating many modalities or technologies can be used to enhance dementia care, which may improve favorable outcomes when using technology-assisted interventions to remotely initiate appropriate activities for people with dementia. Because technology allows for simultaneous communication and access to shared multimedia, it removes environmental constraints and allows treatment to be administered remotely.


Assuntos
Demência , Humanos , Demência/psicologia , Atividades Cotidianas , Qualidade de Vida , Cognição , Cuidados Paliativos
6.
J Prosthet Dent ; 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36631366

RESUMO

STATEMENT OF PROBLEM: Computer-aided design and computer-aided manufacturing (CAD-CAM) technology has greatly improved the efficiency of the fabrication of dental prostheses. However, the design process (CAD stage) is still time-consuming and labor intensive. PURPOSE: The purpose of this feasibility study was to investigate the accuracy of a novel artificial intelligence (AI) system in designing biomimetic single-molar dental prostheses by comparing and matching them to the natural molar teeth. MATERIAL AND METHODS: A total of 169 maxillary casts were obtained from healthy dentate participants. The casts were digitized, duplicated, and processed with the removal of the maxillary right first molar. A total of 159 pairs of original and processed casts were input into the Generative Adversarial Networks (GANs) for training. In validation, 10 sets of processed casts were input into the AI system, and 10 AI-designed teeth were generated through backpropagation. Individual AI-designed teeth were then superimposed onto each of the 10 original teeth, and the morphological differences in mean Hausdorff distance were measured. True reconstruction was defined as correct matching between the AI-designed and original teeth with the smallest mean Hausdorff distance. The ratio of true reconstruction was calculated as the Intersection-over-Union. The reconstruction performance of the AI system was determined by the Hausdorff distance and Intersection-over-Union. RESULTS: Data of validation showed that the mean Hausdorff distance ranged from 0.441 to 0.752 mm and the Intersection-over-Union of the system was 0.600 (60%). CONCLUSIONS: This study demonstrated the feasibility of AI in designing single-molar dental prostheses. With further training and optimization of algorithms, the accuracy of biomimetic AI-designed dental prostheses could be further enhanced.

7.
Molecules ; 28(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36771160

RESUMO

Four novel indane derivatives, anisotindans A-D (1-4), were isolated from the roots of Anisodus tanguticus. Their structures were established using comprehensive spectroscopic analyses, and their absolute configurations were determined by electronic circular dichroism (ECD) calculations and single-crystal X-ray diffraction analyses. Anisotindans C and D (3 and 4) are two unusual indenofuran analogs. ABTS•+ and DPPH•+ assays of radical scavenging activity reveal that all compounds (1-4) are active. Specifically, the ABTS•+ assay results show that anisotindan A (1) exhibits the best antioxidant activity with an IC50 value of 15.62 ± 1.85 µM (vitamin C, IC50 = 22.54 ± 5.18 µM).


Assuntos
Antioxidantes , Antioxidantes/farmacologia , Antioxidantes/química , Estrutura Molecular
8.
Chemistry ; 28(5): e202104001, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34878192

RESUMO

In this study, a novel Rh-iodide complex was synthesized through a surface reaction between an immobilized Rh cyclooctadiene complex and alkylammonium iodide (N+ I- ) on SiO2 . In the presence of ammonium cations, the SiO2 -supported Rh-iodide complex could be effectively used for the one-pot synthesis of various silylcarbonate derivatives starting from epoxy olefins, hydrosilanes, and CO2 . The maximum turnover numbers (TONs) for the hydrosilylation reaction and the CO2 cycloaddition were 7600 (Rh) and 130 (N+ I- ), respectively. The catalyst exhibited much higher performance for hydrosilylation than solely the Rh complex on SiO2 . The mechanism of the Rh-catalyzed hydrosilylation reaction and the local structure of Rh, which is affected by the co-immobilized N+ I- , were investigated by using Rh and I K-edge XAFS and XPS. Analysis of the XAFS profiles indicated the presence of a Rh-I bond. The Rh unit was in its electron-rich state. Curve-fitting analysis of the Rh K-edge EXAFS profiles suggests dissociation of the cycloocta-1,5-diene (COD) ligand from the Rh center. Results from spectroscopic and kinetic analyses revealed that the high activity of the catalyst (during hydrosilylation) could be attributed to a decrease in steric hindrance and the electron-rich state of the Rh. The decrease in the steric hindrance could be attributed to the absence of COD, and the electron-rich state promoted the oxidative addition of Si-H. To the best of our knowledge, this is the first example of a one-pot silylcarbonate synthesis as well as a determination of a novel surface Rh-iodide complex and its catalysis.

9.
Langmuir ; 38(3): 1045-1056, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35020400

RESUMO

When a dry mass of certain amphiphiles encounters water, a spectacular interfacial instability ensues: It gives rise to the formation of ensembles of fingerlike tubular protrusions called myelin figures─tens of micrometers wide and tens to hundreds of micrometers long─representing a novel class of nonequilibrium higher-order self-organization. Here, we report that when phase-separating mixtures of unsaturated lipid, cholesterol, and sphingomyelin are hydrated, the resulting myelins break symmetry and couple their compositional degrees of freedom with the extended myelinic morphology: They produce complementary, interlamellar radial gradients of concentrations of cholesterol (and sphingomyelin) and unsaturated lipid, which stands in stark contrast to interlamellar, lateral phase separation in equilibrated morphologies. Furthermore, the corresponding gradients of molecule-specific chemistries (i.e., cholesterol extraction by methyl-ß-cyclodextrin and GM1 binding by cholera toxin) produce unusual morphologies comprising compositionally graded vesicles and buckled tubes. We propose that kinetic differences in the information processing of hydration characteristics of individual molecules while expending energy dictate this novel behavior of lipid mixtures undergoing hydration.


Assuntos
Bicamadas Lipídicas , Esfingomielinas , Fenômenos Biofísicos , Colesterol
10.
Eur Arch Psychiatry Clin Neurosci ; 272(3): 519-529, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33860331

RESUMO

This study investigated healthcare utilization and expenditure for patients with type 2 diabetes mellitus and schizophrenia and associated factors. Healthcare utilization (outpatient visits and hospitalization) and expenditure (outpatient, inpatient, and total medical expenditure) between 2002 and 2013 of patients with T2DM with schizophrenia (case group) and without (control group) were examined using the Taiwan National Health Insurance Research Database. (1) The average total numbers of outpatient visits and hospital admissions of the case group were 35.14 outpatient visits and 1.09 hospital admissions significantly higher than those of the control group in the whole study period (based on every 3-year period). Nonpsychiatric outpatient visits and nonpsychiatric hospital admissions were significantly more numerous for the case group. (2) The total outpatient expenditure, total inpatient expenditure, and total medical expenditure of the case group were NT$65,000, NT$170,000, and NT$235,000 significantly higher than those of the control group, respectively. Nonpsychiatric outpatient expenditure was significantly lower for the case group, but the inpatient and total nonpsychiatric medical expenditure were similar between groups. (3) Patients who were elder of low income, with complications, and high diabetes mellitus complication severity index had higher total numbers of outpatient visits and hospitalizations and medical expenditure. (4) Women had a higher number of outpatient visits but a lower number of hospitalization and medical expenditure. Lower non-psychiatric outpatient expenditure despite more visits indicated non-psychiatrist may not understand schizophrenia patients and cannot communicate well with them, leading to neglect of medical evaluation and treatment that should be carried out.


Assuntos
Diabetes Mellitus Tipo 2 , Esquizofrenia , Idoso , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/terapia , Feminino , Gastos em Saúde , Hospitalização , Humanos , Programas Nacionais de Saúde , Esquizofrenia/complicações , Esquizofrenia/epidemiologia , Esquizofrenia/terapia
11.
BMC Med Imaging ; 22(1): 176, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36207686

RESUMO

BACKGROUND: We aimed to evaluate the value of using preoperative magnetic resonance imaging (MRI) features and clinical indicators to predict the early response of hepatocellular carcinoma (HCC) to transcatheter arterial chemoembolization (TACE). We also aimed to establish a preoperative prediction model. METHODS: We retrospectively reviewed data of 111 patients with HCC who underwent magnetic resonance imaging (MRI) before the first TACE and underwent MRI or computed tomography between 30 and 60 days after TACE. We used the modified response evaluation criteria in solid tumors for evaluating the TACE response. We used univariate and multivariate logistic regression analyses to identify independent predictors based on MRI features and clinical indicators. Moreover, receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of the prediction model and each independent predictor. RESULTS: Among the 111 included patients, 85 were men (76.6%). Patient age was 31-86 years (average age, 61.08 ± 11.50 years). After the first treatment session, 56/111 (50.5%) patients showed an objective response (complete response + partial response), whereas the remaining showed non-response (stable disease + local progressive disease). In the univariate analysis, we identified irregular margins, number of nodules, and satellite nodules as predictors of early objective response. However, in the multivariate logistic regression analysis, irregular margins, number of nodules and pretreatment platelet were identified as the independent predictors of early objective response. A combined prediction model was then established, which factored in irregular margins, the number of nodules, and the pretreatment platelet count. This model showed good diagnostic performance (area under the ROC curve = 0.755), with the sensitivity, specificity, positive predictive value, and negative predictive value being 78.6%, 69.1%, 72.1%, and 76.0%, respectively. CONCLUSIONS: Irregular margins, the number of nodules and the pretreatment platelet count are independent predictors of the early response of HCC to TACE. Our clinical combined model can provide a superior predictive power to a single indicator.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
12.
Zhongguo Zhong Yao Za Zhi ; 47(20): 5530-5536, 2022 Oct.
Artigo em Zh | MEDLINE | ID: mdl-36471969

RESUMO

This study investigated the chemical components from the florets of Carthamus tinctorius. Five compounds were isolated from C. tinctorius by column chromatography with silica gel and toyopearl HW-40 F, preparative thin-layer chromatography(TLC), and semi-preparative reverse phased high performance liquid chromatography(RP-HPLC). Their structures were identified by mass spectrometry(MS), one-dimension nuclear magnetic resonance(1 D-NMR), two-dimension nuclear magnetic resonance(2 D-NMR), and single-crystal X-ray diffraction as(-)-(2S,3S,5S,7S,10R)-eudesma-4(15)-en-2,3,11-triol(1 a),(+)-(2R,3R,5R,7R,10S)-eudesma-4(15)-en-2,3,11-triol(1 b), rosin(2),(+)-syringaresinol(3), and(E)-1-(4'-hydroxyphenyl)-but-1-en-3-one(4). Compounds 1 a and 1 b are a pair of enantiomeric sesquiterpenoids. Compound 1 a is a new eudesmene and is named(-)-plucheol A. Compound 1 a at 100 µmol·L~(-1) showed significant antioxidant activity against ABTS~(+·) and DPPH·, with the scavenging rates of 30.98%±4.17% and 27.52%±1.24%, respectively, while compound 1 b was inactive. In addition, compounds 1 a and 1 b showed no obvious anti-inflammatory activity.


Assuntos
Carthamus tinctorius , Sesquiterpenos , Carthamus tinctorius/química , Cromatografia Líquida de Alta Pressão/métodos , Sesquiterpenos/química , Estereoisomerismo , Espectrometria de Massas , Estrutura Molecular
13.
Zhongguo Zhong Yao Za Zhi ; 47(12): 3265-3269, 2022 Jun.
Artigo em Zh | MEDLINE | ID: mdl-35851120

RESUMO

Macroporous resin chromatography, silica gel column chromatography, preparative thin layer chromatography, and semi-preparative high performance liquid chromatography were performed to isolate two compounds from the acid extract of the lateral roots of Aconitum carmichaelii: a new 9-phenylisoquinoline alkaloid(1) and a known pavine alkaloid(2). Their structures were elucidated by spectroscopy. The absolute configuration of compound 1 was identified by electronic circular dichroism(ECD) and it was determined to be(aS)-7,8-dimethoxy-9-(2-carboxy-4,5-dimethoxyphenyl)-3,4-dihydroisoquinoline-1(2H)-one(1). The cardioprotective effects of 1 and 2 against doxorubicin-induced toxicity in H9 c2 cells were evaluated. Both of the isoquinoline alkaloids showed cardioprotective activity.


Assuntos
Aconitum , Alcaloides , Medicamentos de Ervas Chinesas , Aconitum/química , Alcaloides/análise , Alcaloides/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Raízes de Plantas/química
14.
Chemistry ; 27(33): 8410, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34050583

RESUMO

Invited for the cover of this issue is Kimihisa Yamamoto and co-workers at Tokyo Institute of Technology and International Christian University. The image depicts enhanced reactivity of the copper oxide subnanoparticles under low-temperature conditions. Read the full text of the article at 10.1002/chem.202100508.

15.
Chemistry ; 27(33): 8452-8456, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33884681

RESUMO

Subnanoparticles (SNPs) with sizes of approximately 1 nm are attractive for enhancing the catalytic performance of transition metals and their oxides. Such SNPs are of particular interest as redox-active catalysts in selective oxidation reactions. However, the electronic states and oxophilicity of copper oxide SNPs are still a subject of debate in terms of their redox properties during oxidation reactions for hydrocarbons. In this work, in situ X-ray absorption fine structure (XAFS) measurements of Cu28 Ox SNPs, which were prepared by using a dendritic phenylazomethine template, during temperature-programmed reduction (TPR) with H2 achieved lowering of the temperature (T50 =138 °C) reported thus far for the CuII →CuI reduction reaction because of Cu-O bond elongation in the ultrasmall copper oxide particles.

16.
Med Sci Monit ; 27: e933400, 2021 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-34921128

RESUMO

BACKGROUND The N-terminal fragment of proB-type natriuretic peptide (NT-proBNP) is an established predictive marker for sepsis-related mortality in adult. This retrospective study aimed to determine age-stratified cut-off values for serum levels of NT-proBNP and mortality from sepsis in children under 18 years. MATERIAL AND METHODS Patients were stratified by age as follows: <1 year, 1-3 years, 4-6 years, and 7-18 years (age groups). The control group consisted of age- and sex-matched healthy children. Serum NT-proBNP levels were detected by laboratory assays in the participants. The appropriate serum NT-proBNP cut-off values for predicting short-term mortality of the sepsis patients were calculated via receiver operating characteristic (ROC) curve analyses. RESULTS Among 327 pediatric patients with sepsis, the serum NT-proBNP cut-off concentrations for predicting sepsis-related mortality in the <1 year, 1-3 years, 4-6 years, and 7-18 years age groups were 5000 ng/L, 4500 ng/L, 4100 ng/L, and 3800 ng/L, respectively (P<0.001). The area under the ROC curve (AUC) values for these were 0.815, 0.812, 0.806 and 0.725, respectively (P<0.001). CONCLUSIONS This retrospective study provided the age range-specific serum NT-proBNP cut- off concentrations for predicting short-term mortality in children. In children <1 year, 1-3 years, 4-6 years, and 7-18 years, age-stratified cut-off values that predicted sepsis-associated mortality were 5000 ng/L, 4500 ng/L, 4100 ng/L, and 3800 ng/L, respectively.


Assuntos
Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Sepse/mortalidade , Adolescente , Fatores Etários , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Curva ROC , Estudos Retrospectivos , Sepse/sangue
17.
Inorg Chem ; 59(21): 15690-15695, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33085886

RESUMO

Carbothermal hydrogen reduction (CHR) is a unique dry chemical process used to fabricate metals and carbides on carbon supports. In this study, a stepwise CHR of WCl6 on a graphite support is demonstrated for the first time. Powder X-ray diffraction studies revealed that, at 773 K, metallic tungsten nanoparticles are produced, whereas, at 1073 K, the metastable W2C phase is generated rather than the thermodynamically stable WC phase. X-ray photoelectron spectroscopy and X-ray absorption near edge structure studies showed that the chemical state of the W nanoparticles simultaneously exhibits metallic W(∼0) and carbide W(δ+) character. The obtained results suggest that, although electronic interactions exist between the metallic W atoms and the graphite support, the body-centered cubic structure of the metallic tungsten is maintained, confirmed by the extended X-ray absorption fine structure. In addition, high-resolution scanning transmission electron microscopy observations revealed that the W nanoparticles exhibit a thin flattened shape on the support. These results support the notion that the mechanism for the formation of the W nanoparticles during the CHR is influenced by the electronic interactions between the W nanoparticles and the graphite support. Our work thus suggests that the combination of early-transition-metal atoms and carbon-based supports would afford modulatable electronic systems though the electronic interactions.

18.
J Asian Nat Prod Res ; 22(12): 1121-1129, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32290704

RESUMO

A new aromatic glycoside (1) and a new natural product, neolignan (2), along with twenty-three known compounds (3-25), were isolated from the thorns of Gleditsia sinensis. According to the spectroscopic analyses (IR, UV, HRESIMS, NMR and ECD), the structures of isolates were elucidated. Herein, compounds 4, 6-8, 10-13, 15, 16, 18, 20, 23 were isolated from the plant of G. sinensis for the first time. Moreover, compounds 4, 6, 15 and 24 showed cytotoxic effects on human ovarian cancer (SKOV-3) cells with IC50 values of 24.83 ± 4.90, 48.86 ± 9.11, 80.13 ± 5.62, 15.38 ± 2.21 µM, respectively. [Formula: see text].


Assuntos
Antineoplásicos , Gleditsia , Glicosídeos/farmacologia , Humanos , Estrutura Molecular , Extratos Vegetais
19.
Molecules ; 24(18)2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31487934

RESUMO

The rattans of Spatholobus suberectus Dunn are a traditional Chinese medicine activating blood circulation and removing stasis. They have often been used for the traditional Chinese medicinal treatment of breast cancer in modern China. In this study, four novel isoflavanes (1-3 and 5) and four known analogues (4 and 6-8) were isolated from an ethanolic extract of the rattans of S. suberectus. Their structures were elucidated by extensive spectroscopic analyses and electronic circular dichroism studies. MCF-7 and MDA-MB-231 human breast cancer cell lines were used to evaluate the cytotoxic effects of the isolates. Interestingly, compounds 1 and 2 only inhibited the proliferation of MCF-7 cells, while compound 6 showed a selective cytotoxicity against MDA-MB-231 cells. However, compound 4 had significant cytotoxicity against both MCF-7 and MDA-MB-231 cell lines.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Fabaceae/química , Isoflavonas/farmacologia , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Neoplasias da Mama , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Isoflavonas/química , Isoflavonas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Relação Estrutura-Atividade
20.
Molecules ; 24(22)2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31739601

RESUMO

Fuzi is a well-known traditional Chinese medicine developed from the lateral roots of Aconitum carmichaelii Debx. It is rich in alkaloids that display a wide variety of bioactivities, and it has a strong cardiotoxicity and neurotoxicity. In order to discriminate the geographical origin and evaluate the quality of this medicine, a method based on high-performance liquid chromatography (HPLC) was developed for multicomponent quantification and chemical fingerprint analysis. The measured results of 32 batches of Fuzi from three different regions were evaluated by chemometric analysis, including similarity analysis (SA), hierarchical cluster analysis (HCA), principal component analysis (PCA), and linear discriminant analysis (LDA). The content of six representative alkaloids of Fuzi (benzoylmesaconine, benzoylhypaconine, benzoylaconine, mesaconitine, hypaconitine, and aconitine) were varied by geographical origin, and the content ratios of the benzoylmesaconine/mesaconitine and diester-type/monoester-type diterpenoid alkaloids may be potential traits for classifying the geographical origin of the medicine. In the HPLC fingerprint similarity analysis, the Fuzi from Jiangyou, Sichuan, was distinguished from the Fuzi from Butuo, Sichuan, and the Fuzi from Yunnan. Based on the HCA and PCA analyses of the content of the six representative alkaloids, all of the batches were classified into two categories, which were closely related to the plants' geographical origins. The Fuzi samples from Jiangyou were placed into one category, while the Fuzi samples from Butuo and Yunnan were put into another category. The LDA analysis provided an efficient and satisfactory prediction model for differentiating the Fuzi samples from the above-mentioned three geographical origins. Thus, the content of the six representative alkaloids and the fingerprint similarity values were useful markers for differentiating the geographical origin of the Fuzi samples.


Assuntos
Aconitum/química , Alcaloides/química , Raízes de Plantas/química , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Análise Discriminante , Análise de Componente Principal
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