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1.
Medicine (Baltimore) ; 100(22): e25984, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34087841

RESUMO

BACKGROUND: As one of the key factors, postoperative recurrence of hepatocellular carcinoma (HCC) influences the therapeutic effects and survival period of patients. Therefore, the early diagnosis of postoperative recurrence of HCC plays an important role in improving the therapeutic effects and prognosis. Contrast-enhanced ultrasound (CEUS) plays an important role in the early diagnosis of postoperative recurrence of HCC. However, the accuracy of CEUS in predicting postoperative recurrence of HCC is still controversial. Therefore, in this study, a meta-analysis was carried out to further evaluate the accuracy of CEUS in predicting postoperative recurrence of HCC, thus providing evidence support for the early diagnosis of HCC. METHODS: The literatures on the CEUS diagnosis of postoperative recurrence of HCC were collected by searching China National Knowledge Infrastructure, Wanfang, China Biology Medicine disc, PubMed, EMBASE, Cochrane Library, and Web of Science on computer. The retrieval time is set from the start of the database until April 2021. The meta-analysis of the literatures that meet the quality standards was conducted by Stata 16.0 software. RESULTS: The results of this meta-analysis will be submitted to a peer-reviewed journal for publication. CONCLUSION: This study will provide evidence support for the accuracy of CEUS in the diagnosis of postoperative recurrence of HCC. ETHICS AND DISSEMINATION: The private information from individuals will not be published. This systematic review also should not damage participants' rights. Ethical approval is not available. The results may be published in a peer-reviewed journal or disseminated in relevant conferences. OSF REGISTRATION NUMBER: DOI 10.17605/OSF.IO/HB46W.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/patologia , Carcinoma Hepatocelular/cirurgia , Diagnóstico Precoce , Humanos , Neoplasias Hepáticas/cirurgia , Prognóstico , Projetos de Pesquisa , Ultrassonografia/métodos , Metanálise como Assunto
2.
Cell Rep ; 7(3): 871-82, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24746824

RESUMO

RAS genes are among the most frequently mutated proto-oncogenes in cancer. However, how Ras stability is regulated remains largely unknown. Here, we report a regulatory loop involving the E3 ligase Nedd4-1, Ras, and PTEN. We found that Ras signaling stimulates the expression of Nedd4-1, which in turn acts as an E3 ubiquitin ligase that regulates Ras levels. Importantly, Ras activation, either by oncogenic mutations or by epidermal growth factor (EGF) signaling, prevents Nedd4-1-mediated Ras ubiquitination. This leads to Ras-induced Nedd4-1 overexpression, and subsequent degradation of the tumor suppressor PTEN in both human cancer samples and cancer cells. Our study thus unravels the molecular mechanisms underlying the interplay of Ras, Nedd4-1, and PTEN and suggests a basis for the high prevalence of Ras-activating mutations and EGF hypersignaling in cancer.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas ras/metabolismo , Animais , Carcinogênese , Linhagem Celular Tumoral , Complexos Endossomais de Distribuição Requeridos para Transporte/antagonistas & inibidores , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Fator de Crescimento Epidérmico/metabolismo , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Camundongos , Camundongos Nus , Células NIH 3T3 , Ubiquitina-Proteína Ligases Nedd4 , Neoplasias/metabolismo , Neoplasias/patologia , PTEN Fosfo-Hidrolase/metabolismo , Ligação Proteica , Transdução de Sinais , Transplante Heterólogo , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Regulação para Cima
3.
Anal Bioanal Chem ; 404(1): 207-16, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22648165

RESUMO

Organochlorine pesticides have been extensively used worldwide for agricultural purposes. Due to their resistance to metabolism, a major public health concern has been raised. Aberrant hepatic lipid composition has been a hallmark of many liver diseases associated with exposure to various toxins and chemicals. And thus lots of efforts have been focused on the development of analytical techniques that can rapidly and quantitatively determine the changes in fatty acid composition of hepatic lipids. In this work, changes in fatty acid composition of hepatic lipids in response to DDT (dichlorodiphenyltrichloroethane) exposure were quantitatively analyzed by a gas chromatography-mass spectrometric approach based on stable isotope-coded transmethylation. It has been quantitatively demonstrated that polyunsaturated fatty acids including C20:3n3, C20:4n6, and C22:6n3 decrease in response to DDT exposure. However, saturated long chain fatty acids including C16:0, C18:0, as well as monounsaturated long chain fatty acid C18:1n9 consistently increase in a DDT-concentration-dependent manner. In particular, much higher changes in the level of hepatic C16:0 and C18:0 for male fish were observed than that for female fish. These experimental results are in accordance with qualitative histopathological analysis that revealed liver morphological alterations. The stable isotope-coded mass spectrometric approach provides a reliable means for investigating hepatotoxicity associated with fatty acid synthesis, desaturation, mitochondrial beta-oxidation, and lipid mobilization. It should be useful in elucidation of hepatotoxic mechanisms and safety assessment of environmental toxins.


Assuntos
DDT/farmacologia , Ácidos Graxos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Marcação por Isótopo/métodos , Fígado/química , Praguicidas/farmacologia , Peixe-Zebra/metabolismo , Animais , Ácidos Graxos/metabolismo , Feminino , Metabolismo dos Lipídeos , Lipídeos/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Metilação , Estrutura Molecular
4.
Anal Chim Acta ; 724: 73-9, 2012 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-22483212

RESUMO

Desalting and concentration of peptides using reverse phase (RP) C18 chromatographic material based on hydrophobic interaction is a routine approach used in mass spectrometry (MS)-based proteomics. However, MS detection of small hydrophilic peptides, in particular, phosphopeptides that bear multiple negative charges, is challenging due to the insufficient binding to C18 stationary phase. We described here the development of a new desalting method that takes the unique properties of polypyrrole (PPY). The presence of positively charged nitrogen atoms under acidic conditions and polyunsaturated bonds in polypyrrole provide a prospect for enhanced adsorption of phosphopeptides or hydrophilic peptides through extra electrostatic and Π-Π stacking interactions in addition to hydrophobic interactions. In tandem with reversed phase C18 chromatographic material, the new type of desalting method termed as TMTip(PPY-C18) can significantly improve the MS detection of phosphopeptides with multiple phosphate groups and other small hydrophilic peptides. It has been applied to not only tryptic digest of model proteins but also the analysis of complex lysates of zebrafish eggs. The number of detected phosphate groups on a peptide ranged from 1 to 6. Particularly, polypyrrole based method can also be used in basic condition. Thus it provides a useful means to handle peptides that may not be detectable in acidic condition. It can be envisioned that the TMTip(PPY-C18) should be able to facilitate the exploration of large scale phosphoproteome.


Assuntos
Cromatografia de Fase Reversa/métodos , Óvulo/química , Fosfopeptídeos/análise , Fosfoproteínas/análise , Polímeros/química , Pirróis/química , Proteínas de Peixe-Zebra/análise , Adsorção , Sequência de Aminoácidos , Animais , Feminino , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Espectrometria de Massas , Dados de Sequência Molecular , Eletricidade Estática , Tripsina/química , Peixe-Zebra/metabolismo
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