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1.
Clin Radiol ; 79(5): e750-e758, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38360515

RESUMO

AIM: To investigate the application of the T2-weighted (T2)-fluid-attenuated inversion recovery (FLAIR) mismatch sign and machine learning-based multiparametric magnetic resonance imaging (MRI) radiomics in predicting 1p/19q non-co-deletion of lower-grade gliomas (LGGs). MATERIALS AND METHODS: One hundred and forty-six patients, who had pathologically confirmed isocitrate dehydrogenase (IDH) mutant LGGs were assigned randomly to the training cohort (n=102) and the testing cohort (n=44) at a ratio of 7:3. The T2-FLAIR mismatch sign and conventional MRI features were evaluated. Radiomics features extracted from T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), FLAIR, apparent diffusion coefficient (ADC), and contrast-enhanced T1WI images (CE-T1WI). The models that displayed the best performance of each sequence were selected, and their predicted values as well as the T2-FLAIR mismatch sign data were collected to establish a final stacking model. Receiver operating characteristic curve (ROC) analyses and area under the curve (AUC) values were applied to evaluate and compare the performance of the models. RESULTS: The T2-FLAIR mismatch sign was more common in the IDH mutant 1p/19q non-co-deleted group (p<0.05) and the area under the curve (AUC) value was 0.692 with sensitivity 0.397, specificity 0.987, and accuracy 0.712, respectively. The stacking model showed a favourable performance with an AUC of 0.925 and accuracy of 0.882 in the training cohort and an AUC of 0.886 and accuracy of 0.864 in the testing cohort. CONCLUSION: The stacking model based on multiparametric MRI can serve as a supplementary tool for pathological diagnosis, offering valuable guidance for clinical practice.


Assuntos
Neoplasias Encefálicas , Glioma , Imageamento por Ressonância Magnética Multiparamétrica , Humanos , Isocitrato Desidrogenase/genética , Radiômica , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Mutação/genética , Glioma/diagnóstico por imagem , Glioma/genética , Glioma/patologia , Imageamento por Ressonância Magnética/métodos , Aprendizado de Máquina , Estudos Retrospectivos
2.
Clin Radiol ; 76(8): 629.e11-629.e18, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34092362

RESUMO

AIM: To differentiate glioblastoma (GBM) from solitary brain metastases (MET) using radiomic analysis. MATERIALS AND METHODS: Two hundred and fifty-three patients with solitary brain tumours (157 GBM and 98 solitary brain MET) were split into a training cohort (n=178) and a validation cohort (n=77) by stratified sampling using computer-generated random numbers at a ratio of 7:3. After feature extraction, minimum redundancy maximum relevance (mRMR) and the least absolute shrinkage and selection operator (LASSO) were used to build the radiomics signature on the training cohort and validation cohort. Performance was assessed by radiomics score (Rad-score), receiver operating characteristic (ROC) curve, calibration, and clinical usefulness. RESULTS: Eleven radiomic features were selected as significant features in the training cohort. The Rad-score was significantly associated with the differentiation between GBM and solitary brain MET (p<0.001) both in the training and validation cohorts. The radiomics signature yielded area under the curve (AUC) values of 0.82 and 0.81 in the training and validation cohorts to distinguish between GBM and solitary brain MET. CONCLUSIONS: The radiomics model might be a useful supporting tool for the preoperative differentiation of GBM from solitary brain MET, which could aid pretreatment decision-making.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/secundário , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Estudos de Coortes , Diagnóstico Diferencial , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos
3.
Clin Radiol ; 74(2): 154-160, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30391048

RESUMO

AIM: To examine whether texture analysis (TA) of diffusion-weighted imaging (DWI) combined with conventional magnetic resonance imaging (MRI) could non-invasively predict isocitrate dehydrogenase 1 (IDH1) mutational status in anaplastic gliomas. MATERIALS AND METHODS: Fifty-two patients with histologically confirmed anaplastic glioma was reviewed retrospectively. Conventional MRI was evaluated using the Visually Accessible Rembrandt Images (VASARI) scoring system. TA of DWI based on the entire tumour volume was compared between IDH1-mutant and wild-type tumours by using unpaired Student's t-test. Receiver operating characteristic curve (ROC) and logistic regression were used to assess their diagnostic performance. RESULTS: Significant statistical differences in VASARI features and TA of DWI were observed between IDH1-mutant and wild-type tumours (all p<0.05). Using multivariable logistic regression, the proportion of the tumour that was non-enhancing and the entropy of apparent diffusion coefficient (ADC) were found to possess higher prediction potential for IDH1 mutation with areas under the ROC curve (AUC) of 0.918 and 0.724, respectively. A combination of these for the identification of IDH1 mutations improved the AUC to 0.954, with a sensitivity and a specificity of 81% and 96%. CONCLUSIONS: The combined assessment of the conventional MRI and TA of DWI were useful for predicting IDH1 mutation in anaplastic gliomas.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Glioma/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Isocitrato Desidrogenase/genética , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Neoplasias Encefálicas/genética , Feminino , Glioma/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
4.
Genet Mol Res ; 12(4): 6860-70, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24391034

RESUMO

A drought-induced gene, DIP3, encoding a chitinase III protein was isolated from the roots of upland rice by reverse transcription-polymerase chain reaction (RT-PCR). Sequence analysis demonstrated that the cDNA and deduced protein showed high identity to Oryza sativa class III chitinase. The deduced protein contained a signal peptide sequence in the N-terminal region of 21aa and a conserved glycosyl hydrolase (GH) 18 domain. The secondary and 3D structures were analyzed and showed that it contained α-helix, ß-sheets, extended strand and random coil structures and that it was approximately spheroidal. Real-time quantitative PCR analysis revealed that expression levels accumulated rapidly under different forms of abiotic stress (drought, salt and low temperature), peaked at different times and then decreased. These results implied that as a member of class III chitinases, DIP3 may function as a stress-induced protein involved in the regulation of plant stress response.


Assuntos
Quitinases/genética , Oryza/genética , Estresse Fisiológico/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , DNA de Plantas/genética , Secas , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Proteínas de Plantas/genética , Estrutura Terciária de Proteína , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
5.
J Cancer Res Clin Oncol ; 130(10): 591-603, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15243805

RESUMO

PURPOSE: Telomerase reverse transcriptase (hTERT) is the key determinant of telomerase activity and plays a crucial role in cellular immortalization and oncogenesis. It will be a promising target for cancer gene therapy. We constructed a novel replicative adenovirus CNHK300 in which hTERT promoter with three extra E-boxes downstream of the promoter was introduced and used to regulate adenoviral E1a gene, and studied its properties of selective replication in cancer cells and antitumoral activity. METHODS: Luciferase assay was used to detect hTERT promoter activity. The selective replication of CNHK300 in cancer cells was investigated by E1a Western blot and green fluorescent protein (GFP) reporter gene assay. The antitumoral activity of CNHK300 and its toxicity were measured on animal models. RESULTS: Luciferase assay showed that introducing extra E-boxes downstream of hTERT promoter is beneficial to decreasing the promoter activity in normal cells without affecting its strong activity in cancer cells. Experiments in vitro and in vivo demonstrated that CNHK300 can selectively target to hTERT-positive cancer cells and replicate in them, resulting in oncolytic or antitumoral effect. CNHK300 is superior to ONYX-015 in terms of selective replication and oncolytic or antitumoral effect. The toxicity assay showed no signs of toxicity to liver cells even at the higher dosage of CNHK300 in vivo. CONCLUSION: The hTERT promoter-controlled, replication-competent adenovirus CNHK300 is a promising system for targeted cancer gene therapy.


Assuntos
Adenoviridae/genética , Neoplasias/enzimologia , Telomerase/genética , Animais , Proteínas de Ligação a DNA , Terapia Genética/métodos , Proteínas de Fluorescência Verde , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias/virologia , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Telomerase/metabolismo
6.
Yi Chuan Xue Bao ; 28(7): 601-5, 2001.
Artigo em Chinês | MEDLINE | ID: mdl-11480170

RESUMO

In order to clarify the frequency of p16INK4 gene inactivation and its relationship with retinoblastoma (Rb) gene expression in non-small cell lung cancer, in situ double hybridization was established with Bio-labelled Rb cDNA probe and Dig-lablled p16INK4 cDNA probe, and immunohistochemistry was carried out with polyclone rabbit antibodies to human p16INK4 and Rb protein. The results showed that positive hybridization of p16INK4 mRNA showed blue with the detecting system of alkiline phosphatase NBT/BCIP, positive hybridization of Rb mRNA showed red with the detecting system of HPR-AEC. The negative ratios of p16INK4 and Rb gene transcription were 22.6%(7/31) and 16.1%(5/31). The results of immunohistochemistry showed that the negative ratio of p16INK4 protein was 42%(13/31) with p16INK4 polyclone antibody, the negative ratio of pRb was 19.4%(6/31) with polyclone antibody. The data indicated that p16INK4 gene and Rb gene are synergistic in the progression of lung cancer, p16INK4 gene plays a significant role in the development of non-small cell lung cancer.


Assuntos
Genes do Retinoblastoma , Genes p16 , Neoplasias Pulmonares/genética , Inibidor p16 de Quinase Dependente de Ciclina/análise , Humanos , Imuno-Histoquímica , Hibridização In Situ , Neoplasias Pulmonares/química , RNA Mensageiro/análise
7.
J R Coll Surg Edinb ; 40(1): 60-1, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7738903

RESUMO

A newly designed surgical procedure of ligation of the thoracic duct without thoracotomy for the treatment of postoperative chylothorax is presented. A case of chylothorax following resection of carcinoma of the oesophagus was treated successfully with ligation of the thoracic duct without thoracotomy. Its advantages were very prominent consisting of maintenance of the integrity of the thorax, less traumatization, no need of a drainage tube and shorter hospitalization, much easier to expose the thoracic duct than the conventional transthoracic approach. We can find no similar report in any published literature.


Assuntos
Quilotórax/cirurgia , Complicações Pós-Operatórias/cirurgia , Ducto Torácico/cirurgia , Neoplasias Esofágicas/cirurgia , Humanos , Ligadura/métodos , Masculino , Pessoa de Meia-Idade , Toracotomia
8.
J Med Virol ; 19(2): 167-73, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3014061

RESUMO

Shexian County of Anhui Province in East China experienced a severe outbreak of nonbacterial diarrhoea in May and June of 1983. Over 20,0000 cases were reported. Most were adults of 20 to 50 years old. The isolated virus was morphologically indistinguishable from ordinary infantile rotavirus, but CF and ELISA tests showed that the new virus lacked the common group-A antigen shared by ordinary rotavirus. Nine of 10 convalescent-phase and three paired sera of patients showed antibody positive, with a greater than four-fold antibody rise against new rotavirus in the CF test. Seventeen faecal samples from patients showed identical, and special, electropherotype. They all had a double-stranded RNA with 11 discrete segments. The RNA profiles were quite different from those of reference rotavirus Wa strain and ordinary infantile rotaviruses. Third and 4th segments were near to each other, 5th and 6th segments were very close, but 7th, 8th, and 9th segments were widely separated. This study indicates the new virus can be identified as part of a new group of rotaviruses. This new rotavirus has been incriminated as the causative agent of the epidemic.


Assuntos
Diarreia/microbiologia , Surtos de Doenças/microbiologia , Infecções por Rotavirus/epidemiologia , Adulto , Anticorpos Antivirais/análise , China , Testes de Fixação de Complemento , Feminino , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , RNA Viral/análise , Rotavirus/patogenicidade , Rotavirus/ultraestrutura
9.
Scand J Work Environ Health ; 11 Suppl 4: 13-5, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3832429

RESUMO

With the reorganization of the grassroots structure and economic readjustment, the commune- and brigade-run plants have now been changed to district (town)- and village-run plants, respectively, and the role of industrial production has become more important to the total income of the people. The Qi-yi Commune (District) is a good example. The number of plants showed an increase of 80% from 1975 to 1983, whereas the number of workers increased by 149%. The number of workers as a percentage of the total population of the district grew from 10% to about 25%. The rapid progress of industry led to a need to promote occupational health services as part of primary health care. This article reviews the implementation of such services with the objective of attaining the goal "Health for all by the year 2000."


Assuntos
Doenças Profissionais/prevenção & controle , Serviços de Saúde do Trabalhador , China , Humanos
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