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1.
Front Oncol ; 12: 1021625, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36620563

RESUMO

Background: Early gastric cancer (EGC) has a high survival rate, but it is difficult to diagnosis. Recently, artificial intelligence (AI) based on deep convolutional neural network (DCNN) has made significant progress in the field of gastroenterology. The purpose of this study was to establish a DCNN assist system to improve the detection of EGC. Methods: 3400 EGC and 8600 benign images were collected to train the DCNN to detect EGC. Subsequently, its diagnostic ability was compared to that of endoscopists using an independent internal test set (ITS, including 1289 images) and an external test set (ETS, including 542 images) come from three digestive center. Results: The diagnostic time of DCNN and endoscopists were 0.028s, 8.05 ± 0.21s, 7.69 ± 0.25s in ITS, and 0.028s, 7.98 ± 0.19s, 7.50 ± 0.23s in ETS, respectively. In ITS, the diagnostic sensitivity and accuracy of DCNN are 88.08%(95% confidence interval,95%CI,85.24%-90.44%), 88.60% (95%CI,86.74%-90.22%), respectively. In ETS, the diagnostic sensitivity and accuracy are 92.08% (95%CI, 87.91%- 94.94%),92.07%(95%CI, 89.46%-94.08%),respectively. DCNN outperformed all endoscopists in ETS, and had a significantly higher sensitivity than the junior endoscopists(JE)(by18.54% (95%CI, 15.64%-21.84%) in ITS, also higher than JE (by21.67%,95%CI, 16.90%-27.32%) and senior endoscopists (SE) (by2.08%, 95%CI, 0.75%-4.92%)in ETS. The accuracy of DCNN model was higher (by10.47%,95%CI, 8.91%-12.27%) than that of JE in ITS, and also higher (by14.58%,95%CI, 11.84%-17.81%; by 1.94%,95%CI,1.25%-2.96%, respectively) than JE and SE in ETS. Conclusion: The DCNN can detected more EGC images in a shorter time than the endoscopists. It will become an effective tool to assist in the detection of EGC in the near future.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 255: 119693, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33784596

RESUMO

A new morpholine functionalized coumarin-based fluorescent probe 1 was easily synthesized. The probe realized the sequentially detecting of Cu2+ and H2S in the HEPES buffer solution (20 mM, pH = 5.0). It made a turn-off fluorescence response to Cu2+ by using a complex formation with a 2:1 binding mode, and the resulting complex was able to detect H2S according to the displacement approach with a turn-on fluorescence response. The detecting limits of probe 1 for Cu2+ and 1-Cu2+ system for H2S were calculated to be 26 nM and 88.5 nM, respectively. This "on-off-on" recognition process was demonstrated by ultraviolet-visible spectroscopy, fluorescence spectroscopy, using proton nuclear magnetic resonance studies, electrospray ionization mass spectroscopy, single crystal X-ray diffraction, and using density functional theory calculations. In addition, both cell imaging and co-staining experiments showed that the probe could be utilized to visually detect Cu2+ and H2S in lysosomes.


Assuntos
Cumarínicos , Hidrazonas , Cobre , Corantes Fluorescentes , Lisossomos , Espectrometria de Fluorescência
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 231: 118110, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32007906

RESUMO

A morpholine-functionalized pyrrole-cyanine probe was synthesized via a simple condensation reaction in high yield. This probe exhibits high selectivity toward ClO- on fluorescence and UV-vis spectra in neat aqueous solution. The strong green emission of the probe solution was quenched and the yellow color faded immediately upon the addition of ClO-. The detection limit of the probe for ClO- was 0.165 µM. The mechanism of hypochlorite-induced CC breakage was supposed on the basis of EIS-MS, NMR, and density functional theory (DFT) calculation. Finally, the probe was utilized to image ClO- in lysosomes of living cells.


Assuntos
Corantes Fluorescentes/química , Ácido Hipocloroso/análise , Lisossomos/química , Células HeLa , Humanos , Lisossomos/ultraestrutura , Microscopia Confocal , Modelos Moleculares , Imagem Óptica , Solubilidade , Espectrometria de Fluorescência , Água/química
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 230: 118025, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31927511

RESUMO

A quinoline-based hydrazone, namely, bis((quinolin-8-yl)methylene)carbonohydrazide (1), has been designed and synthesized, which could be used as a dual probe for selective recognition of Co2+ and Zn2+ by monitoring changes in absorption and fluorescence spectral pattern, respectively. The detection limits of 1 for these two ions are 0.21 and 0.66 µM, respectively. The complex formation between 1 and Co2+/Zn2+ is responsible for the detection process, as confirmed through several spectral methods and DFT calculations. The application of the as-synthesized sensor is demonstrated in Zn2+ imaging in living cells.


Assuntos
Cobalto/análise , Corantes Fluorescentes/química , Hidrazonas/química , Quinolinas/química , Zinco/análise , Cátions Bivalentes/análise , Células HeLa , Humanos , Microscopia de Fluorescência , Modelos Moleculares , Imagem Óptica
5.
Nat Prod Res ; 34(21): 3036-3041, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31240950

RESUMO

Two new sesquiterpenoid glycosides as dihydrophaseic acid 4'-O-[6″-O-(4″'-hydroxy-3″', 5″'-dimethoxy) benzoyl)]-ß-D-glucopyranoside (1) and dihydrophaseic acid 4'-O-[6″-O-(3″'-methoxy- 4″'-hydroxy) benzoyl)]-ß-D-glucopyranoside (2), were isolated from the stems of Zanthoxylum armatum in the study. The compound 1 and 2 showed moderate scavenging activity in DPPH free radical assay with IC50 values of 241 and 264 µM, respectively.


Assuntos
Sesquiterpenos/química , Zanthoxylum/química , Compostos de Bifenilo/química , Sequestradores de Radicais Livres/química , Glicosídeos/química , Estrutura Molecular , Picratos/química , Extratos Vegetais/química , Caules de Planta/química
6.
Molecules ; 23(9)2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30135395

RESUMO

Euphorbia maculata is a medicinal plant of the Euphorbiaceae family, which can produce anti-inflammatory and cancer chemopreventive agents of triterpenoids. The present study reports on the bioactive triterpenoids of this plant. Two new lanostane-type triterpenoids, named (3S,4S,7S,9R)-4-methyl-3,7-dihydroxy-7(8→9) abeo-lanost-24(28)-en-8-one (1) and 24-hydroperoxylanost-7,25-dien-3ß-ol (2), together with 15 known triterpene derivatives, were isolated from Euphorbia maculata. The structures of the new compounds were determined on the basis of extensive spectroscopic data (UV, MS, ¹H and 13C-NMR, and 2D NMR) analysis. All tetracyclic triterpenoids (1⁻11) were evaluated for their anti-inflammatory effects in the test of TPA-induced inflammation (1 µg/ear) in mice. The triterpenes exhibited significant anti-inflammatory activities.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Euphorbia/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Triterpenos/química , Animais , Modelos Animais de Doenças , Edema/tratamento farmacológico , Edema/patologia , Feminino , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular
7.
Nat Prod Res ; 31(13): 1529-1535, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28111967

RESUMO

Rhubarb contains biologically active compounds such as anthraquinones, anthrones, stilbenes and tannins. A rapid and efficient UPLC/Q-TOF-MS/MS method was developed and applied towards identifying the constituents of Rheum tanguticum Maxim. ex Balf. for the first time. Chemical constituents were separated and investigated by UPLC/Q-TOF-MS/MS in the negative ion mode. The ESI-MS2 fragmentation pathways of four types of compounds were interpreted, providing a very useful guidance for the characterisation of different types of compounds. Based on the exact mass information, fragmentation characteristic and LC retention time of 7 reference standards, 30 constituents were tentatively identified from the methanol extract of R. tanguticum. Among them, seven compounds were described for the first time from R. tanguticum and two from the genus Rheum were described for the first time. The analytical tool used here is valuable for the rapid separation and identification of multiple and minor constituents in methanol extracts of R. tanguticum.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/análise , Rheum/química , Espectrometria de Massas em Tandem/métodos , Antraquinonas/análise , Antraquinonas/química , Medicamentos de Ervas Chinesas/química , Metanol , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Estilbenos/análise , Estilbenos/química
8.
J Pharm Biomed Anal ; 123: 16-23, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-26859611

RESUMO

The granule of Chinese medicine (GCM) is prepared by water-soluble extract of single yinpian (WESY) of herbal medicine, and used as a drug ingredient for clinical formulation. The WESY content or corresponding yinpian amount is the most important parameter in evaluating the quality of GCM. Low WESY content reflects poor GCM. Classical quantitative methods, such as HPLC, cannot fully detect the adulteration by adding characteristic ingredients and less WESY production. GCM is composed of WESY and a high content of specific excipient. The WESY content in the GCM may be indirectly analyzed using mid-infrared spectroscopy (MIR). In this paper, a quantitative method to evaluate the quality of Danshen (Salvia miltiorrhiza) granule (DG) was developed using MIR combined with chemometrics. Appropriate characteristic quantitative regions (CQR) were extracted by selecting the spectral regions corresponding to altered excipient content in DG. The best model of dextrin content determination in DG with low RMSEC of 1.97, low RMSEP of 2.07, and excellent RPD of 5.03 (>5.0) was obtained using partial least-squares (PLS) regression, and validated using accepted values of precision and recovery. The results suggest that FT-MIR combined with PLS is a rapid and valuable analytical tool to determine the WESY in DG based on excipient content. The model enabling indirect calculation of WESY content in GCM represents a reference standard for rapid analysis of other WESYs in GCM industry.


Assuntos
Dextrinas/química , Medicamentos de Ervas Chinesas/química , Plantas Medicinais/química , Salvia miltiorrhiza/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Excipientes/química , Análise dos Mínimos Quadrados
9.
J Asian Nat Prod Res ; 18(4): 371-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26268793

RESUMO

Phytochemical investigation on the seeds of Caesalpinia decapetala led to the isolation of a new cassane diterpenoid with an unusual O bridge between C-19 and C-20, named phanginin Q (1), together with three known cassane diterpenoids, caesaljapin (2), caesaldekarin A (3), and caesaldekarin B (4). The structure of the new compound was elucidated by spectroscopic methods, including (1)H NMR, (13)C NMR, HSQC, (1)H - (1)H COSY, HMBC, NOESY, and HR-ESI-MS.


Assuntos
Caesalpinia/química , Diterpenos/isolamento & purificação , Diterpenos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Sementes/química
10.
Artigo em Chinês | MEDLINE | ID: mdl-24818411

RESUMO

OBJECTIVE: To observe the effect of anti-osteopontin antibody on the level of matrix metalloproteinase (MMP-2) and TGF-beta1 in gerbils infected with Echinococcus multilocularis. METHODS: One hundred and eighty gerbils were infected with Echinococcus protoscoleces (approximately 400 for each gerbil) by abdominal opening inoculation in liver. The gerbils were randomly divided into three groups: anti-osteopontin antibody experiment group (group A), rabbit serum injection group (group B), and model group (group C). Gerbils in groups A and B were injected with antiosteopontin antibodies and rabbit serum (0.15 mi/gerbil) via tail vein, respectively. Ten gerbils from each group were sacrificed at 20, 60, 100, 140, 180, and 220 days post-infection, respectively. The liver tissue with hydatid cysts were collected and the expression of MMP-2 and TGF-beta1 was observed by immunohistochemistry staining (SP method). RESULTS: E. multilocularis hydatid tissue spreader over the liver and abdominal cavity. There was no significant difference in the number of MMP-2-positive gerbils among the three groups (P > 0.05). At 100, 140, and 180 days post-infection, the number of TGF-beta1-positive gerbils in group A (3, 2, and 2) was considerably less than that of group B (8, 8, and 9) and group C (8, 9, and 9) (P < 0.05). CONCLUSION: Anti-osteopontin antibody can reduce the expression of TGF-beta1 in hepatic alveolar hydatid tissue of gerbils at certain time, but have no effect on MMP2.


Assuntos
Anticorpos/farmacologia , Equinococose Hepática/metabolismo , Gerbillinae/parasitologia , Metaloproteinase 2 da Matriz/metabolismo , Osteopontina/imunologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Equinococose Hepática/patologia , Fígado/metabolismo , Fígado/patologia , Coelhos
11.
Artigo em Chinês | MEDLINE | ID: mdl-23072158

RESUMO

OBJECTIVE: To observe the effect of anti-osteopontin antibody on the level of IL-2 and IL-5 in the liver of gerbil infected with Echinococcus multilocularis (Em). METHODS: 180 gerbils were infected with echinococcus protoscoleces (approximately 400 for each gerbil) by abdominal opening inoculation in liver. The gerbils were randomly divided into three groups with 60 each: experiment group (group A, with anti-osteopontin antibody interference), control group (group B, with normal rabbit serum injection) and model group (group C, with no interference). Ten gerbils from each group were sacrificed at 20, 60, 100, 140, 180, and 220 days post-infection respectively. The liver tissue with hydatid cysts was collected and the expression of IL-2 and IL-5 was observed after immunohistochemistry staining (SP method). RESULTS: E. multilocularis hydatid tissue spreaded over the liver and abdominal cavity. The positive expression rate of IL-2 in the tissue showed no statistical difference among the three groups (P > 0.05). On the days 140 and 180, however, the positive expression rate of IL-5 in group A was 40% and 20% respectively, considerably lower than that in group B (100% and 90%) and group C (90% and 80% respectively). CONCLUSION: The anti-osteopontin antibody can reduce Th2 type cytokine response in the Em-infected gerbils, which may strengthen the immunity of the host.


Assuntos
Anticorpos Anti-Helmínticos/imunologia , Equinococose/imunologia , Fígado/parasitologia , Osteopontina/imunologia , Animais , Echinococcus multilocularis , Gerbillinae , Interleucina-2/imunologia , Interleucina-5/imunologia
12.
Planta Med ; 73(10): 1112-5, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17611936

RESUMO

Three new sterols, 3beta,16alpha-dihydroxy-5alpha,17beta-cholestan-21-carboxylic acid (1), 3beta-acetoxy-16alpha-hydroxy-5alpha,17beta-cholestan-21-carboxylic acid (2) and 3beta-(3-hydroxybutyroxy)-16alpha-hydroxy-5alpha,17beta-cholestan-21-carboxylic acid (3) were isolated from Selaginella tamariscina (Beauv.) Spring (Selaginellaceae). Their structures were elucidated based on NMR analyses. The growth inhibitory effects and differentiation induction abilities of compounds 1 - 3 were determined in human leukemia HL-60 cells. Compound 1 was more effective than compounds 2 and 3 in inhibiting cell growth, but compound 3 was more effective than compounds 1 and 2 in enhancing induction of all- trans-retinoic acid differentiation.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Selaginellaceae , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Células HL-60/efeitos dos fármacos , Humanos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico
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