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1.
Chemphyschem ; 14(1): 198-203, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23203973

RESUMO

2-Ureido-4(1H)-pyrimidinone-bridged ferrocene-fullerene assembly I is designed and synthesized for elaborating the photoinduced electron-transfer processes in self-complementary quadruply hydrogen-bonded modules. Unexpectedly, steady-state and time-resolved spectroscopy reveal an inefficient electron-transfer process from the ferrocene to the singlet or triplet excited state of the fullerene, although the electron-transfer reactions are thermodynamically feasible. Instead, an effective intra-assembly triplet-triplet energy-transfer process is found to be operative in assembly I with a rate constant of 9.2×10(5) s(-1) and an efficiency of 73% in CH(2)Cl(2) at room temperature.

2.
Mol Biol Rep ; 40(2): 1711-20, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23108995

RESUMO

Resistance to anoikis, the subtype of apoptosis induced by lack of matrix adhesion, contributes to malignant transformation and development of metastasis. MicroRNAs play key regulatory roles in tumorigenesis and metastasis. In this study, we described that miR-26a, which is usually downregulated in tumor cells, is involved in the acquisition of anoikis-resistance of human esophageal adenocarcinoma (EA) cells. Results of qRT-PCR in clinical samples showed that downregulated miR-26a expression is related to tumorigenesis and metastasis of EA. In vitro experiments determined that miR-26a directly participates in the regulation of cell cycle and anoikis of human EA OE33 cells. Further, we identified that Rb1 is the direct functional target of miR-26a, and revealed that the reduction of miR-26a expression leads to increased Rb1 protein level and thus inhibits the function of E2F1, by which it influences the phenotypes of cell cycle and anoikis. The findings we reported here presented the evidence that miR-26a may be involved in regulation of anoikis-resistance of EA cells. Targeting miR-26a may provide a novel strategy to inhibit metastasis.


Assuntos
Adenocarcinoma/metabolismo , Anoikis , Fator de Transcrição E2F1/metabolismo , Neoplasias Esofágicas/metabolismo , MicroRNAs/fisiologia , Proteína do Retinoblastoma/genética , Regiões 3' não Traduzidas , Adenocarcinoma/secundário , Animais , Sequência de Bases , Sítios de Ligação , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação para Baixo , Neoplasias Esofágicas/patologia , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Camundongos , Camundongos Nus , Transplante de Neoplasias , Interferência de RNA , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais , Transcrição Gênica
3.
Bull Environ Contam Toxicol ; 91(4): 460-4, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23918231

RESUMO

This paper reports in vitro effects of individual heavy metals (Cd(2+), Cu(2+) and Hg(2+)), and PAHs, including benzo[a]pyrene(BaP), indeno[1,2,3-cd]pyrene (IP) and fluoranthene (FL), and their mixtures on ethoxyresorufin-O-deethylase (EROD) activities using a plate-reader method. The results showed that all three metals inhibited EROD activity, while BaP/IP significantly induced the enzyme. However, FL alone decreased EROD activity. Moreover, co-treatment with BaP/IP and heavy metals inhibited PAH-induced EROD activities, while combined exposure to FL and heavy metals induced FL-inhibited EROD activities.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Fígado/enzimologia , Metais Pesados/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Fígado/efeitos dos fármacos , Tilápia/fisiologia
4.
Clin Transl Med ; 12(4): e691, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35474446

RESUMO

BACKGROUND: Gastric carcinoma (GC) is one of the most deadly diseases due to tumour metastasis and resistance to therapy. Understanding the molecular mechanism of tumour progression and drug resistance will improve therapeutic efficacy and develop novel intervention strategies. METHODS: Differentially expressed long non-coding RNAs (lncRNAs) in clinical specimens were identified by LncRNA microarrays and validated in different clinical cohorts by quantitative real-time polymerase chain reaction (qRT-PCR), in situ hybridisation and bioinformatics analysis. Biological functions of lncRNA were investigated by using cell proliferation assays, migration assays, xenograft tumour models and bioinformatics analysis. Effects of lncSLCO1C1 on GC cell survival were assessed by comet assays and immunofluorescence assays. Underlying molecular mechanisms were further explored by using a number of technologies including RNA pull-down, mass spectrometry analysis, RNA immunoprecipitation, co-immunoprecipitation, miRNA sequencing, luciferase reporter assays and molecular modelling. RESULTS: LncSLCO1C1 was highly upregulated in GC tissue samples and associated with GC patients' poor overall survival. Overexpression of lncSLCO1C1 promoted proliferation and migration, whereas decreased lncSLCO1C1 expression produced the opposite effects. lncSLCO1C1 also mediated tumour resistance to chemotherapy with oxaliplatin by reducing DNA damage and increasing cell proliferation. Despite sequence overlapping between lncSLCO1C1 and PDE3A, alternations of PDE3A expression had no effect on the GC cell progression, indicating that lncSLCO1C1, not PDE3A, related with the progression of GC cells. Mechanistically, lncSLCO1C1 serves as a scaffold for the structure-specific recognition protein 1 (SSRP1)/H2A/H2B complex and regulates the function of SSRP1 in reducing DNA damage. Meanwhile, lncSLCO1C1 functions as a sponge to adsorb miR-204-5p and miR-211-5p that target SSRP1 mRNA, and thus increases SSRP1 expression. Patients with high expressions of both lncSLCO1C1 and SSRP1 have poor overall survival, highlighting the role of lncSLCO1C1 in GC progression. CONCLUSIONS: LncSLCO1C1 promotes GC progression by enhancing cell growth and preventing DNA damage via interacting and scaffolding the SSRP1/H2A/H2b complex and absorbing both miR-211-5p and miR-204-5p to increase SSRP1 expression.


Assuntos
MicroRNAs , RNA Longo não Codificante , Neoplasias Gástricas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Progressão da Doença , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas de Grupo de Alta Mobilidade/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Transportadores de Ânions Orgânicos , Oxaliplatina/farmacologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Fatores de Elongação da Transcrição/genética , Fatores de Elongação da Transcrição/metabolismo
5.
Nanomedicine (Lond) ; 16(25): 2255-2267, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34569291

RESUMO

Aim: Long noncoding RNA (lncRNA) BC032469-dependent gold nanoparticle molecular beacons (AuNP-MB) were constructed for the detection of gastric cancer cells. Materials & methods: The AuNP-MBs were prepared according to well-established procedures based on the Au-S interaction between the gold lattice and thiol functionalized oligonucleotides. More importantly, the stability and targeting ability of AuNP-MB were verified by a series of in vitro and in vivo experiments. Results: The lncRNA-dependent probes were successfully utilized for AuNP-MB-based intracellular imaging, with fluorescence effectively emitted in GC cells, but not in normal cells. Notably, such fluorescent emission was positively correlated with lncRNA BC032469 expression. Conclusion: The authors developed an effective fluorescent imaging probe for the recognition of gastric cancer cells.


Assuntos
Nanopartículas Metálicas , RNA Longo não Codificante , Neoplasias Gástricas , Corantes Fluorescentes , Ouro , Humanos , RNA Longo não Codificante/genética , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/genética
6.
Zhonghua Jie He He Hu Xi Za Zhi ; 33(7): 500-4, 2010 Jul.
Artigo em Zh | MEDLINE | ID: mdl-20979795

RESUMO

OBJECTIVE: To study the relationship between cAMP response element binding protein (CREB) and the interferon-γ (IFN-γ) proximal promoter in patients with tuberculosis. METHODS: CD3(+) T cells were isolated from 25 pulmonary tuberculosis patients, who had been treated in Beijing Chest Hospital from January to December 2007, and 18 PPD-positive healthy donors. After extraction of nuclear proteins, electrophoretic mobility shift assay (EMSA) was performed to determine nuclear protein binding to the IFN-γ proximal promoter in vitro, and the specificity of binding complex was tested by competitive EMSA. Chromatin immunoprecipitation (ChIP) with anti-CREB Ab was used to determine whether CREB binded to the IFN-γ proximal promoter in vivo in live T cells exposed to microbial Ags. Western blotting with anti-CREB Ab was performed to compare the expression level of CREB in tuberculosis patients and PPD-positive healthy donors. Western blotting with Abs specific for serine 133-phosphorylated CREB was performed to determine whether M.tuberculosis Ags elicited phosphorylation of CREB. RESULTS: The results of EMSA showed a low-mobility complex binding to the IFN-γ promoter, and the binding pattern observed was similar for T cells from all 18 PPD-positive healthy donors. However, for T cells from 18 of 25 tuberculosis patients, the low-mobility complex was absent. The results of competitive EMSA showed that these nuclear proteins specifically bound to the IFN-γ promoter region and contained CREB. The results of ChIP showed a 204 bp band yielded in CD3(+) T cells from 10 PPD-positive healthy donors, but 12 tuberculosis patients didn't yield the band. CREB expression markedly decreased in tuberculosis patients compared with healthy donors detected by Western blotting. Furthermore, M. tuberculosis Ags also elicited phosphorylation of CREB in CD3(+) T cells from PPD-positive healthy donors, but not in CD3(+) T cells from tuberculosis patients. CONCLUSIONS: CREB protein binding to IFN-γ proximal promoter was reduced in tuberculosis patients compared with healthy donors. Tuberculosis patients had diminished CREB protein levels, and reduced ability of binding to the IFN-γ promoter.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Interferon gama/genética , Tuberculose Pulmonar/genética , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Linfócitos T/metabolismo , Tuberculose Pulmonar/metabolismo , Adulto Jovem
7.
Drug Des Devel Ther ; 13: 3171-3180, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31564833

RESUMO

BACKGROUND: Emodin, a major component of Polygonum multiflorum (PM), has been reported to exert both protective and toxic effects in several cell types. However, the effects and underlying mechanisms of action of emodin in hepatic cells are still obscure. METHODS: The present study used the normal human liver cell line L02 to investigate the effects and mechanisms of emodin in hepatic cells. After treatment with emodin, L02 cells were examined for viability, apoptosis and autophagy with the Cell Counting Kit-8 (CCK-8), annexin V/PerCP staining and GFP-LC3 plasmid transfection. The expression of proteins including cleaved caspase-3, LC3B-I/II, p-PI3K, PI3K, p-AKT, AKT, p-mTOR, mTOR and actin was examined by using Western blot. RESULTS: Emodin significantly inhibited the viability of and induced apoptosis in L02 cells in a dose- and time-dependent manner. In addition, emodin increased the number of GFP-LC3 puncta in L02 cells and upregulated the expression of LC3B-II compared to those in control cells. Furthermore, emodin significantly decreased the expression of p-PI3K, p-AKT and p-mTOR in a dose-dependent manner compared to that in control cells without altering the expression of PI3K, AKT and mTOR. Notably, cotreatment with emodin and 3-methyladenine (3-MA) or rapamycin significantly increased and decreased the apoptosis rate of L02 cells, respectively, compared to that of cells treated with emodin alone. CONCLUSION:  In conclusion, emodin exhibited cytotoxicity in the L02 human hepatic cell line by promoting apoptosis, and it also induced autophagy through the suppression of the PI3K/AKT/mTOR signalling pathway. The autophagy could play a protective role following emodin treatment.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Emodina/farmacologia , Hepatócitos/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Emodina/química , Fallopia multiflora/química , Hepatócitos/metabolismo , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Relação Estrutura-Atividade , Serina-Treonina Quinases TOR/metabolismo
8.
Brain Res ; 1233: 176-84, 2008 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-18708037

RESUMO

An increasing number of inherited neurodegenerative diseases are known to be caused by the expansion of unstable trinucleotide repeat tracts. Spinocerebellar ataxia type 8 (SCA8) has been identified as being partly caused by a CTG expansion in an untranslated, endogenous antisense RNA that overlaps the Kelch-like 1 (KLHL1) gene. Clinically, SCA8 patients show similar features to those with the other SCAs, including limb and truncal ataxia, ataxic dysarthria and horizontal nystagmus, all of which are signs of dysfunction of the cerebellar system. However, allele sizes within the SCA8 proposed pathogenic range have been reported in patients with ataxia of unknown etiology, in individuals from pedigrees with other SCA or Friedreich's ataxia, and in patients with Alzheimer's disease, schizophrenia or parkinsonism. These observations suggest that mutation of the SCA8 locus might affect neurons other than the cerebellum. Antisense transcripts are known to regulate complementary sense transcripts and are involved in several biologic functions, such as development, adaptive response, and viral infection. In order to test whether SCA8 affects the KLHL1 expression by antisense RNA in brain cells, we examined the expression pattern of KLHL1 and SCA8 in human tissues and in mouse brain regions. SCA8 expression was colocalized with KLHL1 transcript in many brain regions whose functions are correlated to the clinical symptoms of SCA8 patients. These findings lead to the hypothesis of a possible relevance that SCA8 transcript downregulates KLHL1 expression through an antisense mechanism, which then leads to SCA8 neuropathogenesis.


Assuntos
Encéfalo/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ataxias Espinocerebelares/metabolismo , Testículo/metabolismo , Animais , Cerebelo/metabolismo , Córtex Cerebral/metabolismo , Feminino , Hipocampo/metabolismo , Humanos , Hipotálamo/metabolismo , Rim/metabolismo , Masculino , Camundongos , Proteínas dos Microfilamentos/genética , Proteínas do Tecido Nervoso/genética , Pâncreas/metabolismo , Próstata/metabolismo , RNA Longo não Codificante , RNA Mensageiro/análise , RNA não Traduzido , Tálamo/metabolismo , Distribuição Tecidual
9.
J Phys Chem A ; 112(17): 3865-9, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18393477

RESUMO

Phosphorescence quenching and flash photolysis experiments demonstrate that photoinduced intra-assembly triplet-triplet energy transfer can take place via a 2-ureido-4[1H]-pyrimidinone-bridged benzophenone-naphthalene assembly I with a rate constant of 3.0 x 106 s-1 and an efficiency of 95% in CH2Cl2. This new finding suggests that with high binding strength and directionality, the 2-ureido-4[1H]-pyrimidinone hydrogen-bonded module may serve as a new model to illustrate the fundamental principles governing the triplet-triplet energy-transfer process through hydrogen bonds.


Assuntos
Transferência de Energia , Pirimidinonas/química , Absorção , Benzofenonas/química , Ligação de Hidrogênio , Luminescência , Espectroscopia de Ressonância Magnética , Naftalenos/química , Fotólise , Pirimidinonas/síntese química
10.
Yao Xue Xue Bao ; 43(5): 443-9, 2008 May.
Artigo em Zh | MEDLINE | ID: mdl-18717328

RESUMO

The current status and latest advances in new technique pseudophase biochromatography are reviewed. After brief introduction to the principle of new technique pseudophase biochromatography, the nature and various influence factors including the compositions, the types of new technique pseudophase biochromatography system are summarized in detail and the aspects of the future applications biochromatography in life science are described.


Assuntos
Biotecnologia/métodos , Cromatografia Capilar Eletrocinética Micelar/métodos , Eletroforese Capilar/métodos , Lipossomos , Animais , Cromatografia Líquida/métodos , Humanos , Bicamadas Lipídicas/química , Retinoides/isolamento & purificação
11.
Oncol Lett ; 14(2): 2523-2530, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28781691

RESUMO

Although numerous long non-coding RNAs (lncRNAs) have been identified to be important in human cancer, their potential regulatory roles in epithelial tumorigenesis and tumor progression in ovarian cancer remain unclear. The purpose of the present study was to investigate lncRNAs that were differentially expressed (DE) in epithelial ovarian cancer and to explore their potential functions. The lncRNA profiles in five pairs of human epithelial ovarian cancer tissues and their adjacent normal tissues were described using microarrays. The results of the microarray analysis revealed that 672 upregulated and 549 downregulated (fold-change ≥2.0) lncRNAs were DE between the cancerous and normal tissues. Reverse transcription-quantitative polymerase chain reaction was used to validate the microarray results using four upregulated (RP11-1C1.7, XLOC_003286, growth arrest-specific 5 and ZNF295-AS1) and four downregulated (protein tyrosine kinase 7, maternally expressed gene 3, AC079776.2 and ribosomal protein lateral stalk subunit P0 pseudogene 2) lncRNAs. Furthermore, gene ontology and pathway analyses were used to carry out functional analyses of the candidate genes of DE lncRNAs. The results identified lncRNAs with significantly altered expression profiles in human epithelial ovarian cancer cells compared with those in adjacent normal cells. These data offer new insights into the occurrence and development of epithelial ovarian cancer, and these lncRNAs may provide novel molecular biomarkers for further research on epithelial ovarian cancer.

12.
Int J Nanomedicine ; 12: 1815-1825, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28331307

RESUMO

Tumors are one of the most serious human diseases and cause numerous global deaths per year. In spite of many strategies applied in tumor therapy, such as radiation therapy, chemotherapy, surgery, and a combination of these treatments, tumors are still the foremost killer worldwide among human diseases, due to their specific limitations, such as multidrug resistance and side effects. Therefore, it is urgent and necessary to develop new strategies for tumor therapy. Recently, the fast development of nanoscience has paved the way for designing new strategies to treat tumors. Nanomaterials have shown great potential in tumor therapy, due to their unique properties, including passive targeting, hyperthermia effects, and tumor-specific inhibition. This review summarizes the recent progress using the innate antitumor properties of metallic and nonmetallic nanomaterials to treat tumors, and related challenges and prospects are discussed.


Assuntos
Nanoestruturas/uso terapêutico , Nanotecnologia/tendências , Neoplasias/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Humanos , Nanoestruturas/ultraestrutura
13.
Chin Med J (Engl) ; 130(22): 2661-2665, 2017 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-29133752

RESUMO

BACKGROUND: The Food and Drug Administration recently announced that the use of morcellation may cause fibroids or pelvic dissemination and metastasis of uterine sarcoma; therefore, the use of morcellation is limited in the USA. A large sample study is necessary to assess the proportion of uterine malignant tumors found in patients with laparoscopic myomectomy. METHODS: A national multicenter study was performed in China. From 2002 to 2014, 33,723 cases were retrospectively selected. We calculated the prevalence and recorded the clinical characteristics of the patients with malignancy after morcellation application. A total of 62 cases were finally pathologically confirmed as malignant postoperatively. Additionally, the medical records of the 62 patients were analyzed in details. RESULTS: The proportion of postoperative malignancy after morcellation application was 0.18% (62/33,723) for patients who underwent laparoscopic myomectomy. Nearly 62.9% (39/62) of patients had demonstrated blood flow signals in the uterine fibroids before surgery. And, 23 (37.1%) patients showed rapid growth at the final preoperative ultrasound. With respect to the pathological types, 38 (61.3%) patients had detectable endometrial stromal sarcoma, 13 (21.0%) had detectable uterine leiomyosarcoma, only 3 (3.2%) had detectable carcinosarcoma, and 5 (8.1%) patients with leiomyoma had an undetermined malignant potential. CONCLUSIONS: The proportion of malignancy is low after using morcellation in patients who undergo laparoscopic myomectomy. Patients with fast-growing uterine fibroids and abnormal ultrasonic tumor blood flow should be considered for malignant potential, and morcellation should be avoided.


Assuntos
Morcelação/efeitos adversos , Miomectomia Uterina/efeitos adversos , Neoplasias Uterinas/patologia , Neoplasias Uterinas/cirurgia , Adulto , China , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos
14.
Zhonghua Jie He He Hu Xi Za Zhi ; 29(7): 470-3, 2006 Jul.
Artigo em Zh | MEDLINE | ID: mdl-17045048

RESUMO

OBJECTIVE: A clinical chromatographic fingerprinting of 18 standard strains of Mycobacteria commercialized in China by high-performance liquid chromatography approach was developed and improved in this laboratory. A comparison of clinical chromatographic fingerprintings of mycolic acids was carried out. METHODS: Mycolic acids were extracted from whole cultured cells of Mycobacteria by biochemical methods, and then samples was prepared for analysis after the mycolic acids were saponified, acidified and derived. The samples were detected by high-performance liquid chromatography under optimum conditions. RESULTS: Using above techniques a clinical chromatographic fingerprinting of Mycolic acids analysis was successfully established. The repeatability of the mycolic acids fingerprinting was evaluated. Coefficient of variation (CV) of chromatographic fingerprinting was between 0.20% - 0.83%. CONCLUSIONS: The first clinical chromatographic fingerprinting of 18 standard strains of Mycobacteria in China was established in this laboratory. Mycobacteria can be accurately identified according to chromatographic fingerprinting in a short time. Moreover, there was significant difference between BCG vaccine and Mycobacterium bovis when their peak was compared, which may lead to research of new tools for identifying insidious infection of tuberculosis and for the study of the mechanism of drug tolerance.


Assuntos
Mycobacterium/classificação , Ácidos Micólicos/análise , Mapeamento de Peptídeos , Cromatografia Líquida de Alta Pressão/métodos , Mycobacterium/isolamento & purificação
15.
Oncotarget ; 7(27): 42474-42484, 2016 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-27283901

RESUMO

The early diagnosis and treatment of tumors is of vital significance to increase patient survival. Therefore, we constructed a lentiviral vector expressing tyrosinase (TYR) driven by an optimized human telomerase reverse transcriptase (hTERT) promoter or a cytomegalovirus(CMV) promoter in the hopes of performing noninvasive and real-time tumor-specific imaging. First, hTERT-TYR and CMV-TYR were constructed to infect cancer cell lines (telomerase-negative cell line: U2OS; telomerase-positive cell lines: SGC-7901, SW480 and HepG2). Subsequently, stable tyrosinase-expressing cell lines were sorted by flow cytometry out of these infected cancer cell lines. Then, the mRNA and protein levels of tyrosinase were analyzed. Thetyrosinase activity, melanin production and ferric ion adsorption were measured followed by an MR scan. Consequently the results showed that tyrosinase was only expressed in telomerase-positive tumor cells infected by hTERT-TYR, whereas tyrosinase was expressed in both telomerase-negative and telomerase-positive tumor cells infected by CMV-TYR. Finally, we performed in vivo tumor MR using a clinical 3T MR scanner and found increased signals at T1W1 from telomerase-positive cells infected by hTERT-TYR, which revealed that MR scanning could distinguish cells with hTERT -positive cells from hTERT-negative cells infected with the optimized lentivirus. The mechanism underlying this effect is that tyrosinase promotes melanin production and ferric ion adsorption only in hTERT-expressing cells. Taken together, these data show that this optimized hTERT promoter-driving tyrosinase expression system might be a useful diagnostic tool for the detection of tumors using MR imaging.


Assuntos
Regulação Neoplásica da Expressão Gênica , Espectroscopia de Ressonância Magnética , Monofenol Mono-Oxigenase/metabolismo , Neoplasias/diagnóstico por imagem , Telomerase/genética , Animais , Linhagem Celular Tumoral , Citomegalovirus/genética , Genes Reporter , Terapia Genética/métodos , Células Hep G2 , Humanos , Lentivirus/genética , Melaninas/metabolismo , Camundongos , Camundongos SCID , Transplante de Neoplasias , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Proteínas Recombinantes/metabolismo
16.
Int J Nanomedicine ; 11: 3023-34, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27486320

RESUMO

Gastric cancer is one of the leading causes of tumor-related deaths in the world. Current treatment options do not satisfy doctors and patients, and new therapies are therefore needed. Cerium oxide nanoparticles (CNPs) have been studied as a potential therapeutic approach for treating many diseases. However, their effects on human gastric cancer are currently unknown. Therefore, in this study, we aimed to characterize the effects of CNPs on human gastric cancer cell lines (MKN28 and BGC823). Gastric cancer cells were cocultured with different concentrations of CNPs, and proliferation and migration were measured both in vitro and in vivo. We found that CNPs inhibited the migration of gastric cancer cells when applied at different concentrations, but only a relatively high concentration (10 µg/mL) of CNPs suppressed proliferation. Furthermore, we found that CNPs increased the expression of DHX15 and its downstream signaling pathways. We therefore provide evidence showing that CNPs may be a promising approach to suppress malignant activity of gastric cancer by increasing the expression of DHX15.


Assuntos
Cério/química , Nanopartículas/química , Neoplasias Gástricas/patologia , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Nus , Nanopartículas/ultraestrutura , Metástase Neoplásica , RNA Helicases/genética , RNA Helicases/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/ultraestrutura
17.
Zhonghua Jie He He Hu Xi Za Zhi ; 28(3): 192-4, 2005 Mar.
Artigo em Zh | MEDLINE | ID: mdl-15854417

RESUMO

OBJECTIVE: To study the bactericidal effect of rifapentine and its cross-resistance with rifampin for Mycobacterium tuberculosis and to determine the critical concentration of rifapentine for laboratory drug susceptibility test and therefore to provide the laboratory data for using rifapentine in the treatment of tuberculosis, particularly rifampin resistant tuberculosis. METHODS: We detected the minimal inhibitory concentrations (MICs) of rifampin and rifapentine to H(37) Rv and isolated strains of rifampin susceptible and resistant Mycobacterium tuberculosis by using Middlebrook 7H9, Sauton and Lowenstein-Jensen media. RESULTS: The MICs of rifampin were > or = 0.32 microg/ml for 80% of the 19 rifampin susceptible strains on Middlebrook 7H9 and the MICs of rifapentine ranged from 0.02 microg/ml to 0.32 microg/ml for most of the strains (84%). The MICs of rifapentine were 2 - 4 times lower than those of rifampin to H(37) Rv and most clinical isolates. The rifapentine susceptible isolates were mostly separated from resistant strains at MICs 5-10 microg/ml. CONCLUSIONS: Our results demonstrate the cross resistance of rifampin and rifapentine and the stronger bactericidal potency of rifapentine than rifampin. Some rifampin resistant strains still show susceptibility to rifapentine, which suggests rifapentine may be effective in the treatment of rifampin resistant tuberculosis. Our results also determined a critical resistant concentration of rifapentine for routine drug susceptibility test.


Assuntos
Antibióticos Antituberculose/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Rifampina/análogos & derivados , Rifampina/farmacologia , Meios de Cultura , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana/métodos , Rifampina/metabolismo , Sensibilidade e Especificidade
18.
Zhonghua Jie He He Hu Xi Za Zhi ; 28(12): 841-4, 2005 Dec.
Artigo em Zh | MEDLINE | ID: mdl-16409787

RESUMO

OBJECTIVE: To explore the feasibility of utilizing polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis combined with Southern blot to detect ofloxacin (OFLX)-resistant Mycobacterium tuberculosis, and figure out the boundary between the OFLX-susceptible and resistant Mycobacterium tuberculosis. METHODS: OFLX-resistant Mycobacterium tuberculosis bacilli were induced in vitro and their minimal inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC) were determined. The 320 bp segments of gyrA gene were amplified by PCR and their polymorphism was tested by SSCP from H(37)Rv, H(37)Ra and those induced OFLX-resistant strains. To prove the repeatability of PCR-SSCP combined with Southern blot, 36 clinical isolated OFLX-resistant strains were tested. RESULTS: All of the 85 OFLX-resistant mutations involved in this study were identified to have gyrA mutations. The results showed that there was an overlap if OFLX 10 microg/ml was used as a criteria for discriminating susceptible and resistant strains. Compared with the H(37)Ra, the similar single-stranded shift caused by the single-stranded conformation change was viewed in the 36 clinical isolated OFLX-resistant strains by PCR-SSCP combined with Southern hybridization. CONCLUSIONS: PCR-SSCP analysis combined with Southern blot can clearly distinguish OFLX-susceptible from OFLX-resistant strains. The results suggest that as a cut-off point between OFLX-susceptible and low-level OFLX-resistant to Mycobacterium tuberculosis, OFLX concentration of 10 microg/ml is considered to be a better one.


Assuntos
Mycobacterium tuberculosis/isolamento & purificação , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Antituberculosos/farmacologia , Farmacorresistência Bacteriana Múltipla , Genes Bacterianos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Ofloxacino/farmacologia
19.
Stem Cells Int ; 2015: 960387, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26300925

RESUMO

MSCs have become a popular target for developing end-stage liver therapies. In this study, two models of bone marrow chimeric mice were used to construct the liver failure models. Then it was found that MSCs can transdifferentiate into hepatocyte-like cells and these hepatocyte-like cells can significantly express albumin. Furthermore it was also found that MSCs can fuse with the hepatocytes and these cells had the proliferation activity. However, the percentage of transdifferentiation was significantly higher than fusion. So it was considered that MSCs which transdifferentiated into hepatocyte-likes cells played important roles for repairing the injuring liver function.

20.
Cancer Lett ; 361(1): 57-66, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25727320

RESUMO

Heparanase (HPA) is an endoglucuronidase that can promote the shedding of associated cytokines in several types of tumors. However, little is known about what controls the expression of HPA or its role in gastric cancer. In this study, we report for the first time that HGF regulates HPA expression to promote gastric cancer metastasis. In this study, HGF and HPA were found to be significantly expressed in 58 gastric cancer patients. High expression of both HGF and HPA was positively associated with TNM stage, invasion depth and poor prognosis. In MKN74 cells, exogenous HGF significantly increased HPA expression at both the mRNA and protein levels. Further study revealed that HGF first activated PI3K/Akt signaling. NF-κB signaling was activated downstream of PI3K/Akt and promoted HPA expression. However, when c-met, PI3K/Akt or NF-κB signal inhibitors were used, HPA expression was significantly decreased. All of these results indicate that HGF regulates HPA expression by PI3K/Akt and downstream NF-κB signaling. Using bioinformatics and the ChIP assay, p65 was observed to bind to the HPA promoter. Furthermore, HGF significantly induced tumor cell migration, whereas treatment with an NF-κB inhibitor decreased migration. Moreover, when HPA was overexpressed in MKN74 cells, migration was significantly enhanced, and the HGF concentration was increased. However, when HPA was down-regulated in MKN45 cells, migration and HGF levels decreased. Together, these results demonstrate that HGF/c-met can activate PI3K/Akt and downstream NF-κB signaling to promote HPA expression and subsequent tumor metastasis.


Assuntos
Movimento Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucuronidase/genética , Fator de Crescimento de Hepatócito/farmacologia , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/secundário , Western Blotting , Proliferação de Células/efeitos dos fármacos , Imunoprecipitação da Cromatina , Feminino , Mucosa Gástrica/metabolismo , Glucuronidase/metabolismo , Humanos , Luciferases/metabolismo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , NF-kappa B/genética , Estadiamento de Neoplasias , Fosfatidilinositol 3-Quinases/genética , Prognóstico , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-akt/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Estômago/efeitos dos fármacos , Estômago/patologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidade , Taxa de Sobrevida , Ativação Transcricional/efeitos dos fármacos , Células Tumorais Cultivadas , Regulação para Cima , Cicatrização/efeitos dos fármacos
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