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1.
Chem Sci ; 15(1): 95-101, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38131067

RESUMO

Enhancing the electrochemical activity of graphene holds great significance for expanding its applications in various electrochemistry fields. In this study, we have demonstrated a facile and quantitative approach for modulating the defect density of single-layer graphene (SLG) via an electrochemically induced bromination process facilitated by cyclic voltammetry. This controlled defect engineering directly impacts the heterogeneous electron transfer (HET) rate of SLG. By utilizing Raman spectroscopy and scanning electrochemical microscopy (SECM), we have established a correlation between the HET kinetics and both the defect density (nD) and mean distance between defects (LD) of SLG. The variation of the HET rate (k0) with the defect density manifested a distinctive three-stage behavior. Initially, k0 increased slightly with the increasing nD, and then it experienced a rapid increase as nD further increased. However, once the defect density surpassed a critical value of about 1.8 × 1012 cm-2 (LD < 4.2 nm), k0 decreased rapidly. Notably, the results revealed a remarkable 35-fold enhancement of k0 under the optimal defect density conditions compared to pristine SLG. This research paves the way for controllable defect engineering as a powerful strategy to enhance the electrochemical activity of graphene, opening up new possibilities for its utilization in a wide range of electrochemical applications.

2.
Chem Asian J ; 18(18): e202300491, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37493590

RESUMO

Electrochemical nanoimprint lithography (ECNL) has emerged as a promising technique for fabricating three-dimensional micro/nano-structures (3D-MNSs) directly on semiconductor wafers. This technique is based on a localized corrosion reaction induced by the contact potential across the metal/semiconductor boundaries. The anodic etching of semiconductor and the cathodic reduction of electron acceptors occur at the metal/semiconductor/electrolyte interface and the Pt mold surface, respectively. However, the etching rate is limited by the mass transfer of species in the ultrathin electrolyte layer between the mold and the workpiece. To overcome this challenge, we introduce the ultrasonics effect into the ECNL process to facilitate the mass exchange between the ultrathin electrolyte layer and the bulk solution, thereby improving the imprinting efficiency. Experimental investigations demonstrate a positive linear relationship between the reciprocal of the area duty ratio of the mold and the imprinting efficiency. Furthermore, the introduction of ultrasonics improves the imprinting efficiency by approximately 80 %, irrespective of the area duty ratio. The enhanced imprinting efficiency enables the fabrication of 3D-MNSs with higher aspect ratios, resulting in a stronger light trapping effect. These results indicate the prospective applications of ECNL in semiconductor functional devices, such as photoelectric detection and photovoltaics.

3.
Afr Health Sci ; 14(1): 37-48, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26060456

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common and aggressive cancers worldwide, and the pathogenesis is complicated at present. There iare few effective therapeutic measures, and novel therapeutic strategies are urgently required to improve clinical outcome. Ginkgo biloba extract (EGb) is reported to have an anti-cancer activity. OBJECTIVES: To explore the effect of EGb on expressions of cyclooxygenase-2 (Cox-2) and glutathione S-transferase Pi (GST-Pi) in the pathogenesis of HCC. METHODS: 120 Wistar rats were divided into three groups at random: normal control group (control group), HCC risk group without treatment (HCC risk group), HCC risk group treated with EGb (EGb group); n=40, respectively. The HCC risk in rat was induced by aflatoxin B1 injection. At the end of 13-week, 33-week, 53-week and 73-week, 10 rats in each group were killed and the relevant samples were collected. RESULTS: The mRNA and protein expressions of Cox-2 and GST-Pi were measured by real-time reverse transcription polymerase chain reaction, immunohistochemical analysis and western-blot. When compared with those in the control group in 73-week, the mRNA and protein expressions of GST-Pi in EGb group were weaker than those in HCC risk group in 73-week. However, the mRNA and protein expressions of Cox-2 in HCC risk group were increased than that of control group, and there was no statistical difference for mRNA and protein expressions of Cox-2 between HCC risk group and EGb group. CONCLUSION: EGb can regulate the expression of GST-Pi, but it does not seem to have an effect on Cox-2 expression in the liver of HCC risk rats.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Ginkgo biloba , Glutationa S-Transferase pi/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Animais , Western Blotting , Ciclo-Oxigenase 2/genética , Glutationa S-Transferase pi/genética , Imuno-Histoquímica , RNA Mensageiro , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
4.
Zhonghua Gan Zang Bing Za Zhi ; 20(9): 654-8, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-23207228

RESUMO

OBJECTIVE: To determine the methods for establishing an in vivo model of long-term hepatitis B virus (HBV) infection in the Chinese tree shrew (Tupaia belangeri chinensis). METHODS: Seventy-seven neonate (1-3 days old) and 49 young adult (2 weeks to 1 year old) tree shrews were inoculated with different HBV sources (chronic hepatitis B (CHB) human patient serum, single or pooled; HBV-infected tree shrew serum, single only; HBV-infected HepG2.2.15 cells' culture medium supernatant; HBV genome-transfected HepG2.2.15 cells' culture medium supernatant) through various routes of injection (subcutaneous, intraperitoneal, and direct liver via abdominal skin; adults also received intravenous and indirect liver via spleen). Serum and liver biopsies were collected from the animals at various time points post-inoculation for detection of HBV markers by fluorescence quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, time-resolved immunofluorescence, Southern blotting, dot blotting, immunohistochemistry, and microscopy. RESULTS: Among the neonatal group of tree shrews, six (7.8%) were confirmed as HBV-infected for more than 72 (up to 228) weeks after inoculation and another seven (9.1%) were suspected of persistent infections. None of the young adult tree shrews developed persistent infection. Inoculation with single-source serum from either CHB humans or tree shrews were responsible for the most cases of infections, and the subcutaneous injection produced more infections than the other inoculation routes. The most reliable methods of determining HBV infection status were detection of serum HBV immunoreactive markers and intrahepatic HBV DNA. CONCLUSION: In order to establish an in vivo model of CHB in the tree shrew, the animals should be inoculated in the neonatal period using subcutaneous injection.


Assuntos
Modelos Animais de Doenças , Vírus da Hepatite B , Hepatite B Crônica/virologia , Animais , Feminino , Células Hep G2 , Humanos , Masculino , Tupaia
5.
Zhonghua Gan Zang Bing Za Zhi ; 20(4): 270-4, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22964147

RESUMO

OBJECTIVE: To evaluate the utility of the cross-species screening strategy for investigating key molecule(s) involved in onset and progression of hepatocellular carcinoma (HCC). METHODS: HCC-related molecule data from our previous studies and in the literature were collected to establish a cross-species dataset. Tissue samples of HCC, non-HCC surrounding liver (para-HCC), and normal liver that were collected from humans, tree shrews and rats. The genes reported to have the most differential expression in HCC were verified by analyzing the mRNA and protein levels by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting, respectively. RESULTS: The cross-species dataset of HCC-related molecules included four genes: epidermal fatty acid-binding protein (E-FABP), liver (L)-FABP, tyrosine a-ketoglutarate transaminase (TKT), and cytokeratin (CK8). In humans, E-FABP mRNA expression was significantly higher (P less than 0.05) in HCC (0.87+/-0.14 vs. para-HCC: 0.64+/-0.12 and normal liver: 0.67+/-0.07; F=20.910). Similar results were obtained in tree shrew (HCC: 0.87 +/- 0.25 vs. para-HCC: 0.73 +/- 0.19 and normal liver: 0.68+/-0.19; F=3.807) and rat (HCC: 0.97+/-0.22 vs. para-HCC: 0.78+/-0.16 and normal liver: 0.80 +/- 0.13; F=4.482). The Western blotting analyses revealed a similar statistically significant trend. CONCLUSION: The cross-species screening strategy for tumor genes may represent a feasible and convenient process of identifying key molecule(s) for human HCC. E-FABP may be a particularly crucial molecule for hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Adulto , Idoso , Animais , Estudos de Casos e Controles , Epiderme/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ratos , Tupaiidae/metabolismo
6.
Anal Chem ; 83(12): 4930-5, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21561110

RESUMO

In this paper, we present an electrochemically driven large amplitude pH alteration method based on a serial electrolytic cell involving a hydrogen permeable bifacial working electrode such as Pd thin foil. The method allows solution pH to be changed periodically up to ±4~5 units without additional alteration of concentration and/or composition of the system. Application to the acid-base driven cyclic denaturation and renaturation of 290 bp DNA fragments is successfully demonstrated with in situ real-time UV spectroscopic characterization. Electrophoretic analysis confirms that the denaturation and renaturation processes are reversible without degradation of the DNA. The serial electrolytic cell based electrochemical pH alteration method presented in this work would promote investigations of a wide variety of potential-dependent processes and techniques.


Assuntos
Ácidos/química , DNA/química , Técnicas Eletroquímicas/métodos , Biocatálise , Eletrodos , Enzimas/metabolismo , Concentração de Íons de Hidrogênio , Desnaturação de Ácido Nucleico , Renaturação de Ácido Nucleico , Paládio/química
7.
Dongwuxue Yanjiu ; 32(1): 104-8, 2011 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-21341392

RESUMO

Hepatitis B virus (HBV) infection is one of the important health problems worldwide, especially in China. Feasible and effective animal models of HBV infection in vivo are prerequisite for the HBV-related basic and clinical studies. Located in the highly prevalent region of HBV and hepatocellular carcinoma (HCC), the laboratory of Guangxi Cancer Institute has focused on the cause, pathogenesis and chemoprevention of HCC, and has started the work of establishing tree shrew (Tupaia) models of HBV infection in vivo since the early 1980s. This paper provides an overview of the research process, and highlights the new progress on the chronic infection of tree shrews after inoculated with HBV neonatally in vivo.


Assuntos
Modelos Animais de Doenças , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/virologia , Tupaiidae , Animais , Vírus da Hepatite B/genética , Humanos , Tupaiidae/virologia
8.
Zhonghua Gan Zang Bing Za Zhi ; 18(9): 666-71, 2010 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-20943077

RESUMO

OBJECTIVE: To explore the biological function and possible underlying mechanism of aldo-keto reductase family 1 member B10 (AKR1B10) gene during hepatocarcinogenesis. METHODS: A pair of chemically synthesized small interfering RNA (siRNA) targeting on AKR1B10 was transfected into liver cancer cell line MHCC97H by LipofectamineTM 2000. After confirming the interfering effects of AKR1B10-siRNAs through Quant SYBR Green polymerase chain reaction (Real-time PCR), Western blot and enzymatic activity assay, the capabilities of proliferation and apoptosis of the transfected cells were observed by CCK-8 assay and flow cytometry analysis, and the expressions of a group of tumor-related gene such as c-myc, c-fos, N-ras were observed through Real-time PCR. RESULTS: The expressions of AKR1B10 and the enzymatic activity were down-regulated significantly in AKR1B10-siRNA-transfected cells. Compared with mock and blank control groups, cell growth in AKR1B10-siRNA-transfected group was inhibited by 26.6%+/-3.1% at 72h after transfection. The ratio of apoptotic cells was 37.3%+/-1.0% in AKR1B10-siRNA-transfected group, which was significantly higher than that in mock and blank control groups (P < 0.01). Real-time PCR showed that the expressions of oncogene c-myc, c-fos and N-ras, and the proliferation-associated gene ki-67 were down-regulated in AKR1B10-siRNA-transfected cells, while the expressions of apoptosis-promoting gene caspas-3 and bax were up-regulated. CONCLUSIONS: AKR1B10 might promote proliferation, inhibit apoptosis and then induce malignant transformation of hepatocytes by regulating the expression level of some tumor-related genes.


Assuntos
Aldeído Redutase/genética , Inativação Gênica , RNA Interferente Pequeno , Aldo-Ceto Redutases , Linhagem Celular Tumoral , Expressão Gênica , Humanos , RNA Interferente Pequeno/genética
9.
Zhonghua Gan Zang Bing Za Zhi ; 17(9): 669-74, 2009 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19785954

RESUMO

OBJECTIVE: To screen the differentially expressed proteins especially at the precancerous stage of diethylnitrosamine (DEN) induced hepatocarcinogenesis by comparative proteome research. METHODS: Rats were divided into normal and DEN groups and sacrificed periodically. The liver samples were stained with gamma-glutamyl transpeptidase (GGT) and HE to distinguish the preneoplastic lesion (pre-HCC) from the normal and HCC tissues. The two-dimensional electrophoresis (2-DE) and mass spectrometry (MALDI-TOF-MS/MS) were then applied to analyze the differentially expressed protein between pre-HCC and normal tissues, pre-HCC and HCC, as well as HCC and normal tissues. A few of the candidate proteins such as laminin receptor 1 (67LR) and agmatinase were validated by Western blot and RT-PCR. RESULTS: Totally, there were 82 proteins that differentially expressed two fold or more in one kind of tissues sample than the other, 47 of which occurred in the pre-HCC tissues. Eight proteins including 67LR were consistently up-regulated from normal tissue to pre-HCC and then to HCC tissues, while 22 proteins including agmatinase showed progressively down-regulated in these tissues samples. CONCLUSION: The protein expression profiles are different during the process of hepatocarcinogenesis. Further study on the differentially expressed protein, especially these upregulated in the precancerous stage such as 67LR and agmatinase, might contribute to prevention and early diagnosis of human HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Fígado/metabolismo , Lesões Pré-Cancerosas/metabolismo , Proteínas/metabolismo , Animais , Western Blotting , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/patologia , Dietilnitrosamina , Fígado/patologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/patologia , Masculino , Proteínas de Neoplasias/metabolismo , Lesões Pré-Cancerosas/patologia , Proteoma , Ratos , Ratos Wistar , Receptores de Laminina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Ureo-Hidrolases/metabolismo , gama-Glutamiltransferase
10.
Zhonghua Gan Zang Bing Za Zhi ; 17(8): 580-4, 2009 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19719914

RESUMO

OBJECTIVE: To observe the hepatitis B virus (HBV) replication in the tree shrews that were inoculated with HBV at neonatal period. METHODS: Six new-born tree shrews were inoculated with human HBV positive serum. Blood samples and liver biopsies were collected at different time points after inoculation. The HBV infection markers were tested by nested polymerase chain reaction (nPCR), fluorescence quantitative polymerase chain reaction (FQ-PCR), Southern blot, ELISA and immunohistochemistry staining. The liver tissues were observed under electron and light microscope. RESULTS: 48 weeks after inoculation, HBV DNA and HBV cccDNA were detected in the serum and liver samples of three animals (number 1, 2 and 6) by nPCR. The copy-numbers of HBV DNA detected by FQ-PCR in their serum and liver samples were 103 and-104/ml respectively,and the total DNA in 1microg liver tissue was 107-108. Southern blot indicated that HBV replication intermediates such as HBV cccDNA and HBV ssDNA was detectable in liver tissues. HBsAg was detected by ELISA, and immunohistochemical staining showed a gradual increase of HBsAg-positive liver cells. High copy number of HBV DNA and suspected HBV EM particles could be detected in the liver samples from one of the three animals that have survived more than 2 years after inoculation. The other three animals showed low HBV DNA copy number, and the rest of the signs of HBV infection were negative or transiently positive. CONCLUSIONS: Neonatal tree shrews can be infected with human HBV. HBV can replicate inside the liver cells of tree shrew.


Assuntos
Vírus da Hepatite B/fisiologia , Hepatite B/virologia , Fígado/virologia , Replicação Viral , Animais , Animais Recém-Nascidos , Biópsia , DNA Circular/análise , DNA Circular/sangue , DNA Viral/análise , DNA Viral/sangue , Modelos Animais de Doenças , Hepatite B/etiologia , Hepatite B/patologia , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Humanos , Imuno-Histoquímica , Fígado/patologia , Reação em Cadeia da Polimerase/métodos , Tupaiidae
11.
Zhong Yao Cai ; 32(1): 92-6, 2009 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-19445131

RESUMO

OBJECTIVE: To investigate the effect of Ginkgo biloba extracts (EGb761) on aflatoxin B1 (AFB1)-induced hepatocarcinogenesis and its antioxidant activity in Wistar rats. METHODS: 71 Wistar rats were randomly divided into three groups: AFB1 (group A); AFB1 +EGb761 (group B), Control (group C). Rats in gurop A and B were injected with AFB, through abdomen and the doses were 100-200 microg/kg, one to three times a week. Liver biopsy were performed in all rats during 14th w, 28th w, 42th w and 55th w, and were executed at 64th w. Gammaglutamyl transpeptidase-positive hyperplastic cell foci (gamma-GT foci) and histopathology of the liver tissue were observed. The levels of malondialdehyde (MDA), as well as the activity of Glutathione peroxidase (GSH-Px) was examined. RESULTS: At 42th w and 55th w, the gamma-GT focus area (mm2/focus) and general area of foci (mm2/cm2) of group B were significantly smaller than that in group A (P = 0.000). The incidence of hepatocelluiar carcinoma (HCC) in group B (26.92%) was significantly lower than that in group A(76%) (P = 0.000). Group C didnt have HCC development. EGb 761 markedly increased GSH-Px activity, reduced MDA levels (P < 0.05). CONCLUSION: EGB761 shows effective inhibition to hepatocarcinogenesis induced by AFB1 in rats, which may be related to its antioxidant activity.


Assuntos
Antioxidantes/farmacologia , Ginkgo biloba/química , Neoplasias Hepáticas Experimentais/patologia , Extratos Vegetais/farmacologia , Aflatoxina B1/toxicidade , Animais , Glutationa Peroxidase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Malondialdeído/metabolismo , Folhas de Planta/química , Plantas Medicinais/química , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Distribuição Aleatória , Ratos , Ratos Wistar
12.
Zhonghua Gan Zang Bing Za Zhi ; 16(6): 435-9, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18578994

RESUMO

OBJECTIVES: To study the biological function and its possible underlying mechanism of peroxiredoxin II (PrxII) in liver cancer cell line Hep3B. METHODS: Two pairs of double-stranded small interfering RNA (siRNA) targeted on PrxII gene were transfected into Hep3B cells using LipofectamineTM 2000. After confirming the inhibited effects of these siRNAs through Quant SYBR Green polymerase chain reaction and Western blot, the biological characters of Hep3B cell were analyzed by flow cytometry analysis, MTT and colony formation assays. Furthermore, dichlorodihydrofluorescein diacetate (DCFH-DA) and thiobarbituric acid (TBA) assays, for measuring the products of oxidative reaction, such as the reactive oxygen species (ROS) and malondialdehyde (MDA), were applied to explore whether the antioxidant mechanism was involved in the effects of PrxII functioning on Hep3B cell. RESULTS: The two pairs of siRNA significantly inhibited PrxII mRNA and protein expression. Compared to the mock and blank control groups, the two PrxII-silent groups showed decreased rates of cell growth and clone formation and increased rates of cell apoptosis. The numbers of the formed colonies were 42.0+/-2.8 and 40.5+/-0.7 respectively in the two PrxII-silent groups, while they were 121.5+/-2.1 and 130.0+/-1.4 in the mock and blank control groups (P less than 0.05). The levels of endogenous ROS and MDA were significantly higher in the two PrxII-silent groups than those in the mock and blank control groups (P less than 0.05). CONCLUSION: PrxII might play an important role in the hepatocarcinogenesis, possibly through an antioxidant function which may provide a favorable microenvironment for cancer cell survival and progression.


Assuntos
Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Peroxirredoxinas/genética , RNA Interferente Pequeno , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/patologia , Estresse Oxidativo , Espécies Reativas de Oxigênio , Transdução de Sinais , Transfecção
14.
Ai Zheng ; 26(10): 1085-9, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17927878

RESUMO

BACKGROUND & OBJECTIVE: South Guangxi is an area with high incidence of hepatocellular carcinoma (HCC), and with severe contamination of dietary aflatoxin B1 (AFB1). The activation of beta-Catenin is involved in many cancers. AFB1 may play a key role in hepatocarcinogenesis. This study was to explore the expression and mutation of beta-Catenin in HCC patients from the area with high exposure level of AFB1. METHODS: The expression of beta-Catenin in 52 specimens of HCC and para-HCC tissues, and 18 specimens of non-cancerous liver tissues from South Guangxi were detected by direct sequencing, reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemistry, and Western blot. RESULTS: No mutation in exon 3 of beta-Catenin gene was found in HCC tissues. The mRNA level of beta-Catenin was significantly higher in HCC tissues than in para-HCC tissues and non-cancerous tissues (0.42+/-0.24 vs. 0.20+/-0.16 and 0.23+/-0.12, P<0.01). The positive rate of beta-Catenin was significantly higher in HCC tissues than in para-HCC tissues (55.8% vs. 36.5%, P<0.05). The expression of beta-Catenin mRNA showed no significant correlation to clinicopathologic parameters of HCC (all P>0.05), while the expression of beta-Catenin protein was significantly correlated to metastasis, relapse, portal vein embolus, and clinical stage (all P<0.05). CONCLUSION: Beta-catenin is overexpressed in HCC, but its overexpression has no correlation to gene mutation at GSK-3beta phosphorylation sites in exon 3.


Assuntos
Carcinoma Hepatocelular/metabolismo , Éxons/genética , Neoplasias Hepáticas/metabolismo , Mutação , beta Catenina/biossíntese , Sequência de Bases , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Pessoa de Meia-Idade , Dados de Sequência Molecular , Metástase Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Células Neoplásicas Circulantes/patologia , Fosforilação , Veia Porta/patologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , beta Catenina/genética
16.
Zhonghua Gan Zang Bing Za Zhi ; 15(5): 366-9, 2007 May.
Artigo em Chinês | MEDLINE | ID: mdl-17524271

RESUMO

OBJECTIVE: To evaluate the mRNA and protein expressions of peroxiredoxin II (PrxII) in hepatocellular carcinoma (HCC) and their significance. METHODS: HCC was induced by aflatoxin B1 (AFB1) in 6 tree shrews (Tupaia belangeri chinensis). The expression levels of PrxII mRNA and protein were detected by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot on HCC tissues and on their surrounding liver tissues (para-HCC). Biopsied liver tissues were taken before the HCC induction (pre-HCC) from the same animals and from a group of blank controlled animals that served as controls. Liver biopsy specimens from 18 cases of human HCC and from 17 healthy human volunteers were studied using the same methods. RESULTS: The mRNA and protein expressions of PrxII in tree shrew HCC tissues were significantly higher than those in para-HCC and pre-HCC tissues, and also higher than those in the liver tissues from the control animals (all P < 0.05). The expression levels of PrxII mRNA and protein in human HCC tissues were also significantly higher than those in their para-HCC tissues and in the human normal liver tissues (P < 0.05). CONCLUSION: PrxII might play an important role in hepatocarcinogenesis and might be used as a molecular target for HCC prevention and treatment.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Peroxirredoxinas/genética , Adulto , Idoso , Animais , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais/patologia , Masculino , Pessoa de Meia-Idade , Tupaiidae
17.
Zhonghua Zhong Liu Za Zhi ; 29(9): 662-5, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-18246794

RESUMO

OBJECTIVE: To determine the dynamic expression of survivin gene in hepatocarcinogenesis of rats induced by aflatoxin B1 (AFB1). METHODS: 78 Sprague-Dawley rats were used in this study. Hepatocellular carcinoma was induced in the rats by aflatoxin B1. Liver and HCC tissues were examined by immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: The earliest hepatocellular carcinoma occurred at 46th week after AFB1 treatment. The HCC incidence was 54.9% (28/51) at 46th week and 64.9% (24/37) at 58th week. The positive rates of survivin protein expression in 24 HCC, para-cancerous liver tissues of experimental group were 41.7% and 54.2%, respectively, with no significant difference between them (P > 0.05). No survivin expression was detected in the experimental group before 46th week, neither in the rats without HCC occurrence nor the normal controls. The level of survivin mRNA expression in HCC at 58th week was significantly higher than that in pre-HCC, no-HCC and normal liver tissues in the control group (P < 0.01). The level of survivin mRNA expression in para-carcinoma tissues was also significantly higher than that in no-HCC and normal liver tissues of the control (P < 0.01). The level of survivin mRNA in pre-HCC at 12th, 20th, 36th, 46th weeks were significantly higher than those in normal liver tissues taken from control group during the same periods (P < 0.01). CONCLUSION: The over-expression of survivin gene is related to the occurrence of HCC and may play an important role in the carcinogenesis of HCC.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Aflatoxina B1 , Animais , Proteínas Reguladoras de Apoptose/genética , Regulação Neoplásica da Expressão Gênica , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/induzido quimicamente , Masculino , Proteínas Associadas aos Microtúbulos/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Survivina
18.
Zhonghua Gan Zang Bing Za Zhi ; 13(10): 763-7, 2005 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16248950

RESUMO

OBJECTIVES: To study the differential expression of genes in signal transduction pathway (STP) during the hepatocarcinogenesis in tree shrews induced by AFB1 and/or HBV and to elucidate the molecular mechanism of hepatocellular carcinoma (HCC) development. METHODS: Adult tree shrews were divided into three groups: Group A was fed AFB1 only, Group B was infected firstly with HBV then fed AFB1 as in Group A, Group C served as the normal control. Liver biopsies were obtained at the 30th, 60th and 90th week of the experiment or until HCC occurred and the animals were sacrificed. Tree shrew-specific cDNA microarray was applied for detecting the differential expression of corresponding genes in each group at different time points during the experiment, and real time RT PCR was applied to verify the results of the cDNA microarray. RESULTS: Genes of IGF-II, C-rel, and NF-kappaB2 were differentially expressed between para-cancerous tissues and HCC tissues in both group A and group B, and the differential expression of bcl-2, cyclin A and CNTF was only seen in group B. Between the experimental groups A and B and the control group C, there were differential expressions of CNTF and cyclin A in the early 30th week and middle 60th week stage of hepatocarcinogenesis in tree shrews. Real time RT PCR results showed that the expression level of IGF-II and C-Rel in group A and of IGF-II in group B in HCC tissues were significantly lower than that in the adjacent non-cancerous tissues and in the biopsies taken at the 30th and 60th week of the experiment. Nevertheless, there were no significant differences between the para-cancerous tissues and the cancer tissues at the 30th and 60th week. These results were consistent with the cDNA microarray assay. The expression levels of C-Rel and CNTF in group B were not obviously altered in the para-cancerous tissues, HCC and at the 60th week, but they were significantly lower in these tissues than that in the tissues at the 30th week. In group A, the expression levels of CNTF in adjacent liver and HCC tissues were higher than that in para-cancerous lesions, but the difference did not reach a statistically significant level. In group C, the expression level of IGF-II, C-Rel and CNTF at different stages showed no significant differences, which was consistent with the cDNA microarray results. CONCLUSIONS: To apply the tree shrew-specific cDNA microarray to detect the differential expression of genes related to signal transduction pathway during tree shrew hepatocarcinogenesis could be a valuable utility for further comprehending the mechanism of HCC. IGF-II, NF-kappaB2, C-rel, Bcl-2, and cyclin A. CNTF may be involved in the occurrence and progress of HCC in tree shrews.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas Experimentais/genética , Análise de Sequência com Séries de Oligonucleotídeos , Transdução de Sinais , Animais , Feminino , Perfilação da Expressão Gênica , Masculino , Tupaiidae
19.
World J Gastroenterol ; 11(30): 4740-4, 2005 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-16094721

RESUMO

AIM: To explore the expression of p53, bcl-2, bax, survivin and the cell apoptosis during the development of tree shrew hepatocellular carcinoma (HCC), the relationship between expression of these genes, its impact on HCC development, and its relation to cell apoptosis. METHODS: Tree shrew HCC was induced with aflatoxin B1 (AFB1), and regular biopsy of liver tissues was carried out and the biopsy tissues were collected during cancer inducement. Liver biopsy tissue and HCC tissue were collected from 35 pre-cancerous experimental animals at wk 30 and 60 and at the 30th-, 60th-, and 90th-wk. Liver biopsy tissues were collected from 13 blank control animals at wk 30, 60, and 90. Expression of p53, bcl-2, bax, and survivin at each stage was examined by immunohistochemistry method. Apoptotic cells were detected in situ by the terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) technique. RESULTS: The apoptosis rate of normal hepatic cells was extremely low, whereas it increased during the formation of HCC. Expression of the apoptosis-related genes p53, bcl-2, bax, and survivin during the formation of HCC presented an increasing tendency. Expression of p53 did not noticeably relate to that of bcl-2, bax, and survivin, whereas expression of bcl-2 and bax was closely related. In HCC, p53 did not present a distinct relation to cell apoptosis, whereas its high level expression was probably related to liver cell proliferation. Survivin negatively correlated apoptosis index, and its overexpression could inhibit cell apoptosis. CONCLUSION: Apoptosis-related genes p53, bcl-2, bax, and survivin are all related to the occurrence of HCC. The anti-apoptosis effect of bcl-2 is influenced by bax, and ratio bcl/bax reflects more correctly the extent of cell apoptosis.


Assuntos
Apoptose/genética , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/patologia , Aflatoxina B1/toxicidade , Animais , Expressão Gênica , Genes bcl-2 , Genes p53 , Neoplasias Hepáticas Experimentais/induzido quimicamente , Proteínas Associadas aos Microtúbulos/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Tupaiidae , Proteína X Associada a bcl-2
20.
Ai Zheng ; 24(7): 842-5, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16004812

RESUMO

BACKGROUND & OBJECTIVE: The major cause of death in breast cancer patients is distant metastasis. This study was to explore the expression and significance of small breast epithelial mucin (SBEM) mRNA, the specific marker of breast cancer, in peripheral blood of breast cancer patients. METHODS: Expression of SBEM mRNA in peripheral blood samples from 67 breast cancer patients, 16 benign breast disease patients, and 20 healthy volunteers was detected by nested reverse transcription-polymerase chain reaction (nested RT-PCR). RESULTS: SBEM mRNA was not detected in healthy volunteers and benign breast disease patients. Positive rate of SBEM mRNA was 50.7% (34/67) in breast cancer patients. Positive rate of SBEM mRNA was 25.0% (2/8) in stage I patients, 45.8% (11/24) in stage II patients, 43.8% (7/16) in stage III patients, and 73.7% (14/19) in stage IV patients, respectively. Positive rate of SBEM mRNA was significantly higher in stage IV patients than in stages I, II, and III patients (P0.05). The expression of SBEM mRNA in peripheral blood was not correlated with patient's age, primary tumor size, pathologic type, and estrogen or progestin receptor status (P0.05). CONCLUSION: SBEM mRNA is specifically expressed in peripheral blood of breast cancer patients, and may be a marker of micrometastasis of breast cancer.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Mucinas/biossíntese , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Feminino , Fibroma/metabolismo , Fibroma/patologia , Humanos , Pessoa de Meia-Idade , Mucinas/genética , Estadiamento de Neoplasias , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de Estrogênio/sangue , Receptores de Progesterona/sangue
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