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1.
Lancet Gastroenterol Hepatol ; 8(5): 432-445, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36931287

RESUMO

BACKGROUND: Oesophageal squamous cell carcinoma and adenocarcinoma of the oesophagogastric junction have a dismal prognosis, and early detection is key to reduce mortality. However, early detection depends on upper gastrointestinal endoscopy, which is not feasible to implement at a population level. We aimed to develop and validate a fully automated machine learning-based prediction tool integrating a minimally invasive sponge cytology test and epidemiological risk factors for screening of oesophageal squamous cell carcinoma and adenocarcinoma of the oesophagogastric junction before endoscopy. METHODS: For this multicohort prospective study, we enrolled participants aged 40-75 years undergoing upper gastrointestinal endoscopy screening at 39 tertiary or secondary hospitals in China for model training and testing, and included community-based screening participants for further validation. All participants underwent questionnaire surveys, sponge cytology testing, and endoscopy in a sequential manner. We trained machine learning models to predict a composite outcome of high-grade lesions, defined as histology-confirmed high-grade intraepithelial neoplasia and carcinoma of the oesophagus and oesophagogastric junction. The predictive features included 105 cytological and 15 epidemiological features. Model performance was primarily measured with the area under the receiver operating characteristic curve (AUROC) and average precision. The performance measures for cytologists with AI assistance was also assessed. FINDINGS: Between Jan 1, 2021, and June 30, 2022, 17 498 eligible participants were involved in model training and validation. In the testing set, the AUROC of the final model was 0·960 (95% CI 0·937 to 0·977) and the average precision was 0·482 (0·470 to 0·494). The model achieved similar performance to consensus of cytologists with AI assistance (AUROC 0·955 [95% CI 0·933 to 0·975]; p=0·749; difference 0·005, 95% CI, -0·011 to 0·020). If the model-defined moderate-risk and high-risk groups were referred for endoscopy, the sensitivity was 94·5% (95% CI 88·8 to 97·5), specificity was 91·9% (91·2 to 92·5), and the predictive positive value was 18·4% (15·6 to 21·6), and 90·3% of endoscopies could be avoided. Further validation in community-based screening showed that the AUROC of the model was 0·964 (95% CI 0·920 to 0·990), and 92·8% of endoscopies could be avoided after risk stratification. INTERPRETATION: We developed a prediction tool with favourable performance for screening of oesophageal squamous cell carcinoma and adenocarcinoma of the oesophagogastric junction. This approach could prevent the need for endoscopy screening in many low-risk individuals and ensure resource optimisation by prioritising high-risk individuals. FUNDING: Science and Technology Commission of Shanghai Municipality.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/diagnóstico , Carcinoma de Células Escamosas do Esôfago/epidemiologia , Estudos Prospectivos , China/epidemiologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Junção Esofagogástrica/patologia , Aprendizado de Máquina , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/epidemiologia
2.
Technol Cancer Res Treat ; 21: 15330338221074498, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35099325

RESUMO

Object: By retrospectively analyzing the energy spectrum of squamous cell carcinoma, adenocarcinoma, small cell lung cancer (SCLC), and pulmonary metastases that underwent dual-layer detector spectral computed tomography (DLCT) 3-phase scan of the chest, we explored the value of a multiparameter energy spectrum in the assessment of pathological types of lung tumors. Methods: Cases of squamous cell carcinoma (n = 20), adenocarcinoma (n = 24), SCLC (n = 26), and metastases (n = 14) were collected. Then the largest cross-sectional area (LCA) of the lesion, computed tomography (CT) values in the plain scan phase, arterial and venous phases (HU, HUa, and HUv), iodine concentration, and effective atomic number in the arterial and venous phases (ICa, ICv, Zeff[a], and Zeff[v]) were measured and compared among the nonsmall cell lung cancer (NSCLC), SCLC and metastases, and other 3 groups of SCLC, squamous cell carcinoma, and adenocarcinoma. Results: Only the LCA is statistically different among SCLC, NSCLC, and metastases (P < .05). And the treated subgroup analysis did not show significant differences among the groups. However, the untreated subgroup analysis showed that there was a significant difference between NSCLC and metastases in LCA, SCLC and metastases in ICa, NSCLC and SCLC in HUv, NSCLC and SCLC in Zeff(v) (P < .05). Conclusion: The energy spectrum parameters of DLCT have a certain clinical value in distinguishing NSCLC from SCLC in the Zeff(v) and distinguishing SCLC from metastases in the ICa.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Tomografia Computadorizada por Raios X/métodos , Idoso , Tomada de Decisão Clínica , Diagnóstico Diferencial , Gerenciamento Clínico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/normas
3.
J Magn Reson Imaging ; 47(6): 1572-1577, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29236342

RESUMO

BACKGROUND: Previous studies indicated that two-dimensional-susceptibility weighted imaging (2D-SWI) could serve as a useful biomarker for differentiating the grade of liver fibrosis. PURPOSE: To evaluate the feasibility of 2D-SWI in the dynamic quantification of renal fibrosis in a rabbit model. STUDY TYPE: Longitudinal study. ANIMAL MODEL: Twenty-Four New Zealand White Rabbits including control group (n = 4); and renal fibrosis group (n = 20), by means of a unilateral ureteral obstruction (UUO) model. FIELD STRENGTH/SEQUENCE: The 3.0 T SWI using a 2D gradient-echo sequence. ASSESSMENT: The relative SWI signal ratio(r) of cortical and medulla (r = SIrenal /SImuscle ) was longitudinally assessed before ligation and on weeks 2, 4, 6, and 8 following ligation. Sirius Red staining was used to assess the degree of fibrosis in five high-power fields. STATISTICAL TESTS: The repeated measures of analysis of variance and linear regression analysis. RESULTS: Both the cortical and medullary r values were significantly higher in the UUO kidneys at week 2 compared with the kidneys before ligation. Over the course of UUO progression, significant changes occurred in the cortical and medullary r values in vivo and fibrosis scores in vitro (all P values < 0.05). The r values gradually decreased, while the fibrosis scores gradually increased over 8 weeks following ligation. The linear regression analysis showed a strong and significant correlation between cortical and medullary r values and the pathologic fibrosis scores (R2 = 0.91, 0.81, respectively). DATA CONCLUSION: The SWI sequence could provide a quantitative evaluation of renal fibrosis during UUO progression. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:1572-1577.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Nefropatias/diagnóstico por imagem , Rim/diagnóstico por imagem , Imageamento por Ressonância Magnética , Ureter/diagnóstico por imagem , Obstrução Ureteral/patologia , Animais , Artefatos , Modelos Animais de Doenças , Progressão da Doença , Fibrose , Rim/patologia , Nefropatias/patologia , Modelos Lineares , Estudos Longitudinais , Masculino , Coelhos , Ureter/patologia
4.
PLoS One ; 10(8): e0134895, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26308863

RESUMO

Aster tianmenshanensis G. J. Zhang & T. G. Gao, a new species of Asteraceae from southern China is described and illustrated based on evidence from morphology, micromorphology and molecular phylogeny. The new species is superficially similar to Aster salwinensis Onno in having rosettes of spatulate leaves and a solitary, terminal capitulum, but it differs by its glabrous leaf margins, unequal disc floret lobes and 1-seriate pappus. The molecular phylogenetic analysis, based on nuclear sequences ITS, ETS and chloroplast sequence trnL-F, showed that the new species was nested within the genus Aster and formed a well supported clade with Aster verticillatus (Reinw.) Brouillet et al. The new species differs from the latter in having unbranched stems, much larger capitula, unequal disc floret lobes, beakless achenes and persistent pappus. In particular, A. tianmenshanensis has very short stigmatic lines, only ca. 0.18 mm long and less than 1/3 of the length of sterile style tip appendages, remarkably different from its congeners. This type of stigmatic line, as far as we know, has not been found in any other species of Aster. The very short stigmatic lines plus the unequal disc floret lobes imply that the new species may have a very specialized pollination system, which may be a consequence of habitat specialization. The new species grows only on the limestone cliffs of Mt. Tianmen, Hunan Province, at the elevation of 1400 m. It could only be accessed when a plank walkway was built across the cliffs for tourists. As it is known only from an area estimated at less than 10 km2 and a walkway passes through this location, its habitat could be easily disturbed. This species should best be treated as Critically Endangered based on the International Union for Conservation of Nature Red List Categories and Criteria B2a.


Assuntos
Aster/classificação , Biodiversidade , Carbonato de Cálcio , Espécies em Perigo de Extinção , China , Filogenia
5.
Int J Pharm ; 367(1-2): 58-64, 2009 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-18848870

RESUMO

To investigate the structure-permeability relationship of dietary/nutriceutic flavonoids, the transepithelial transport and cellular uptake of 36 flavonoids (including flavones, flavonols, dihydroflavones, dihydroflavonols, isoflavones, chalcones, flavanes, flavanols, methylated and glycosidic derivatives) were investigated using the Caco-2 cell monolayer. The apparent permeability coefficients (P(app)) of the flavonoids were calculated from bilateral transport assays in the Transwell system with flavonoid determination using a high performance liquid chromatography (HPLC) coupled with a UV detector. The most flavonoids exhibited concentration-independent P(app) values and a ratio of 0.5-1.8 for P(app AB to BL)/P(app BL to AB), suggesting passive diffusion pathways. However, certain flavonoids e.g. morin and some flavonoid glycosides may involve the efflux mechanisms. For isoflavones, flavones, and dihydroflavones, the oil/water partition coefficients (additionally modified by the number and position of the three hydroxyl groups) was the key determinant for Caco-2 cell permeation. However, the permeability of flavonols is more complex with their structure possibly related to their high rate of cell accumulation. Overall, the parental skeleton structure, the number and position of free hydroxyl groups, accumulation and efflux in Caco-2 cell play the key roles in the transport of flavonoids across Caco-2 cell monolayer.


Assuntos
Flavonoides/farmacologia , Absorção Intestinal , Modelos Biológicos , Transporte Biológico , Células CACO-2 , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Flavonoides/química , Humanos , Estrutura Molecular , Permeabilidade , Relação Estrutura-Atividade , Fatores de Tempo
6.
Bioorg Med Chem Lett ; 17(4): 1107-11, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17118653

RESUMO

The uptake and transepithelial transport of the three main constituents macrocarpal A (M-A), macrocarpal B (M-B), and cypellocarpa C (Cy-C) from the fruits of Eucalyptus globulus Labill. were investigated. Monolayers of the human intestinal epithelial cancer cell line Caco-2 were incubated with M-A, M-B, and Cy-C to model its intestinal absorption and transport, respectively. The determination of compounds was performed by HPLC. The apparent permeability coefficients (P(app)) for M-A, M-B, and Cy-C in the apical-to-basolateral direction of a Caco-2 monolayer were (1.70+/-0.06)x10(-6), (1.99+/-0.10)x10(-6), and (6.08+/-0.41)x10(-6)cm/s, respectively. In the presence of iodoacetamide, the P(app) of Cy-C were both reducted in apical-to-basolateral and basolateral-to-apical directions. M-A and M-B appear to accumulate in the epithelial cells. The intestinal absorption of M-A, M-B, and Cy-C was passive diffusion as the dominating process and Cy-C was partly ATP-dependent.


Assuntos
Antivirais/farmacocinética , Eucalyptus/química , Frutas/química , Alquilantes/química , Antivirais/isolamento & purificação , Disponibilidade Biológica , Células CACO-2 , Bloqueadores dos Canais de Cálcio/farmacologia , Membrana Celular/metabolismo , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Humanos , Absorção Intestinal , Iodoacetamida/farmacologia , Floroglucinol/análogos & derivados , Floroglucinol/química , Floroglucinol/farmacocinética , Propionatos/farmacologia , Quinolinas/farmacologia , Sesquiterpenos/química , Sesquiterpenos/farmacocinética , Verapamil/farmacologia
7.
J Protein Chem ; 22(5): 417-22, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14690243

RESUMO

Calf intestinal alkaline phosphatase (CIP) was denatured in 3.0 M guanidine hydrochloride for 2 h at 25 degrees C, before being diluted 20-fold with 0.1 M, pH 8.0, Tris-HCl buffer solution containing various effector molecules such as Mg2+, Zn2+, and nucleotide phosphate. The reactivation courses of the enzyme were investigated by the level of activity recovery, the recovery rate constant, and the relative standard deviation of the data. In the presence of effectors, the courses under reducing and nonreducing conditions of disulfide bonds of protein were compared. It was concluded that for CIP, Mg2+ is a more efficient inducer of reconstitution of the active site and appears to play a specific role. In addition, the present study discusses the differences in the refolding effectors between bacterial and mammalian enzymes.


Assuntos
Fosfatase Alcalina/metabolismo , Intestinos/enzimologia , Dobramento de Proteína , Animais , Bovinos , Cinética , Magnésio/metabolismo , Magnésio/farmacologia , Conformação Proteica/efeitos dos fármacos , Desnaturação Proteica/efeitos dos fármacos , Renaturação Proteica/efeitos dos fármacos , Espectrometria de Fluorescência , Zinco/metabolismo , Zinco/farmacologia
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