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1.
Chem Sci ; 15(11): 4019-4030, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38487248

RESUMO

The development of boron delivery agents bearing an imaging capability is crucial for boron neutron capture therapy (BNCT), yet it has been rarely explored. Here we present a new type of boron delivery agent that integrates aggregation-induced emission (AIE)-active imaging and a carborane cluster for the first time. In doing so, the new boron delivery agents have been rationally designed by incorporating a high boron content unit of a carborane cluster, an erlotinib targeting unit towards lung cancer cells, and a donor-acceptor type AIE unit bearing naphthalimide. The new boron delivery agents demonstrate both excellent AIE properties for imaging purposes and highly selective accumulation in tumors. For example, at a boron delivery agent dose of 15 mg kg-1, the boron amount reaches over 20 µg g-1, and both tumor/blood (T/B) and tumor/normal cell (T/N) ratios reach 20-30 times higher than those required by BNCT. The neutron irradiation experiments demonstrate highly efficient tumor growth suppression without any observable physical tissue damage and abnormal behavior in vivo. This study not only expands the application scopes of both AIE-active molecules and boron clusters, but also provides a new molecular engineering strategy for a deep-penetrating cancer therapeutic protocol based on BNCT.

2.
China CDC Wkly ; 4(35): 788-792, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36284604

RESUMO

Introduction: Foodborne botulism is a rare, potentially fatal illness resulting from the ingestion of foods contaminated with preformed botulinum neurotoxin types A, B, E, or F, produced by Clostridium botulinum. The descriptive epidemiology of foodborne botulism outbreaks in China during 2004-2020 was performed to inform public health response strategies. Methods: Data from 22 of 31 provincial-level administrative divisions (PLADs) of the National Foodborne Disease Outbreaks Surveillance System during 2004-2020 and Embase, China National Knowledge Infrastructure (CNKI), Wanfang Data, and Chinese Science and Technique Journals (CQVIP) from January 2004 to December 2020 to identify indexed publications in the Chinese literature using the following search terms "botulism," or "botulinum toxin," or "Clostridium botulinum." The number and proportion of outbreaks, illnesses, and deaths by PLAD, food types, and contributing factors were calculated. Results: During 2004-2020, a total of 80 foodborne botulism outbreaks occurred in China, involving 386 illnesses and 55 deaths; most outbreaks were reported between June and August, with a sharp peak in January; 22 out of 31 PLADs reported foodborne botulism outbreaks, Xinjiang reported the largest number of outbreaks (20), followed by Qinghai (13); the most commonly implicated foods were home-prepared traditional processed stinky tofu and dried beef, accounting for 51.25% events. Improper processing and improper storage in contributing factors accounted for 77.50% outbreaks. Initial misdiagnosis occurred in 27.50% of cases. Conclusions: Outbreaks of foodborne botulism had a high case-fatality rate. Targeted food safety and popularization education to farmers and herdsmen in Xinjiang and Qinghai related to botulism prevention should be carried out, and timely outbreak investigation and hospital surge capacity should be improved.

3.
Oncol Lett ; 15(5): 7369-7375, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29725450

RESUMO

Although previous studies have demonstrated that dysregulation of microRNA (miR)-126 is associated with the progression of several types of cancer, including lung cancer, the relationship between miR-126 and lung cancer metastasis remains unclear. SPC-A1 lung cancer cells were transfected with miR-126 mimic and negative control using Lipofectamine® 3000. Following 2 h, TGF-ß1 was used to induce epithelial-to-mesenchymal transition (EMT). The protein expression levels of EMT markers: E-cadherin, fibronectin, N-cadherin and vimentin were detected by western blot analysis or immunofluorescence staining. The results demonstrated that ectopic expression of miR-126 significantly suppresses the epithelial-to-mesenchymal transition process, which is considered to be the initial step of tumor metastasis, in SPC-A1 lung cancer cells. In addition, lentivirus-delivered miR-126 was demonstrated to endow Lewis lung carcinoma (LLC) cells with the ability to suppress lung metastasis in vivo. Previous studies have demonstrated that the molecular signals for this phenomenon involve the inhibition of the phosphoinositide 3-kinase/protein kinase B/Snail pathway by miR-126. The protein levels of p-PDK1 (S241) and p-AKT (S473) decreased in miR-126 mimic transfected SPC-A1 and LLC cells, compared with the control group, which were detected by western blot analysis. Reverse transcription-quantitative polymerase chain reaction and western blot analysis results indicated that the expression of Snail decreased in miR-126 mimic transfected SPC-A1 and LLC cells. In conclusion, these results revealed an important role for miR-126 in the regulation of the invasive and metastatic potential of lung cancer, and suggested a potential application for miR-126 in lung cancer treatment.

4.
Oncotarget ; 8(14): 23564-23574, 2017 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-28423597

RESUMO

Estrogen receptor alpha positive (ER+) of breast cancer could develop resistance to antiestrogens including Tamoxifen. Our previous study showed that the E3 ubiquitin ligase HRD1 played an important role in anti-breast cancer. However, its role in chemotherapy resistance hasn't been reported. In this study, we found that HRD1 expression was downregulated in Tamoxifen-resistant breast cancer cell line MCF7/Tam compared to the Tamoxifen sensitive cell line MCF7. Moreover, S100A8 is the direct target of HRD1 by proteome analysis. Our data showed that HRD1 decreased the protein level of S100A8 through ubiquitination while HRD1 was regulated by acetylation of histone. More importantly, HRD1 knockdown significantly increased the cell survival of MCF7 cells to the Tamoxifen treatment. HRD1 overexpression sensitized MCF7/Tam cells to the Tamoxifen treatment in vitro and in vivo. In conclusion, the decrease of HRD1 expression contributed to Tamoxifen resistance in breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Calgranulina A/metabolismo , Tamoxifeno/farmacologia , Ubiquitina-Proteína Ligases/metabolismo , Acetilação , Animais , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Calgranulina A/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Antagonistas de Estrogênios/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Humanos , Células MCF-7 , Camundongos Nus , Microscopia de Fluorescência , Ligação Proteica , Proteólise/efeitos dos fármacos , Proteômica/métodos , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Int J Gynecol Cancer ; 26(2): 331-40, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26807564

RESUMO

OBJECTIVES: For patients with endometrial cancer (EC), the screening value of serum human epididymis protein 4 (HE4) remains controversial. We performed meta-analyses to compare the screening accuracy of serum HE4 and carbohydrate antigen 125 (CA125) for EC. MATERIALS AND METHODS: A search of diagnostic test studies was performed in 5 English databases: Pubmed, Cochrane Library, Web of Science, Science Direct, and Elton Bryan Stephens Co or EBSCO; and 2 Chinese databases including China National Knowledge Infrastructure or CNKI and VIP (Weipu Database), from their inception dates to early July 2015. Two reviewers independently selected trials, conducted critical appraisal, and extracted data. Meta-analyses were performed to compare the screening accuracy between HE4 and CA125. Summary receiver operating characteristic curve and the area under the summary receiver operating characteristic curve were performed. Subgroup analysis, meta-regression, sensitivity analysis, and Egger plot and the Egger test were also conducted. RESULTS: Twenty-one studies were identified, and the methodological quality was generally fair. Meta-analyses revealed that the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratios for HE4 in screening EC were 0.56, 0.89, 6.41, 0.49, and 14.82, respectively, whereas the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for CA125 in screening EC were 0.32, 0.81, 2.15, 0.83, and 2.74, respectively. The areas under the summary receiver operating characteristic curves for HE4 and CA125 were 0.7778 and 0.5474, respectively. CONCLUSIONS: This study indicates that serum HE4 may be superior to CA125 in screening accuracy of EC. This conclusion has to be interpreted cautiously owing to high heterogeneity and some limitations.


Assuntos
Antígeno Ca-125/sangue , Neoplasias do Endométrio/sangue , Proteínas de Membrana/sangue , Proteínas/metabolismo , Feminino , Humanos , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos
6.
Oncotarget ; 6(40): 42854-67, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26536657

RESUMO

HRD1 (3-hydroxy-3-methylglutaryl reductase degradation) is an E3 ubiquitin ligase. We found that HRD1 was significantly downregulated in 170 breast cancer tissues. Low tumoral HRD1 expression was correlated with clinicopathological characteristics and a shorter survival in breast cancer patients. P65 specifically bound to the HRD1 promoter and inhibited HRD1 expression. Suppression of NF-κB activity reversed IL-6-induced downregulation of HRD1 expression. HRD1 interacted with IGF-1R and promoted its ubiquitination and degradation by the proteasome. Overexpression of HRD1 resulted in the inhibition of growth, migration and invasion of breast cancer cells in vitro and in vivo. Furthermore, HRD1 attenuated IL-6-induced epithelial-mesenchymal transition in MCF10A cells. These findings uncover a novel role for HRD1 in breast cancer.


Assuntos
Neoplasias da Mama/patologia , Transição Epitelial-Mesenquimal/fisiologia , Receptor IGF Tipo 1/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Idoso , Animais , Western Blotting , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Imunoprecipitação da Cromatina , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Xenoenxertos , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real , Análise Serial de Tecidos , Transfecção
7.
J Transl Med ; 13: 100, 2015 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-25889022

RESUMO

BACKGROUND: Ganoderma lucidum polysaccharides (GLPS) have been used as traditional Chinese medicine for their properties of cancer prevention and immunomodulation. However, it is unclear whether GLPS has therapeutic effect on anti-hepatocellular carcinoma (HCC) in vivo. In this study, the effect of GLPS and their impact on the balance of regulatory T cell (Treg) and effector T cell (Teff) was measured in a model of hepatoma-bearing mice. METHODS: The effect of GLPS and their impact on the balance of regulatory T cell (Treg) and effector T cell (Teff) were measured in a model of hepatoma-bearing mice. Real-time PCR detected the levels of MicroRNAs (miRNAs) and mRNA. The effects of Tregs on Teff proliferation were determined via suppression assay. The mircroRNA-125b (miR-125b) inhibitor was used to down-regulate miR-125b expression. RESULTS: GLPS significantly suppressed tumor growth in hepatoma-bearing mice associated with an increase of the ratio of Teffs to Tregs. Moreover, GLPS eliminate Treg suppression of Teff proliferation with an increase in IL-2 secretion. Addition of GLPS to treat T cells inhibited Notch1 and FoxP3 expression through increase of miR-125b expression. In hepatoma-bearing mice, miR-125b inhibitor obviously abolished the effect of GLPS on tumor growth. CONCLUSIONS: This finding provides the novel evidence for GLPS on inhibition of HCC through miR-125b inhibiting Tregs accumulation and function.


Assuntos
Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Regulação para Baixo/efeitos dos fármacos , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Polissacarídeos/farmacologia , Linfócitos T Reguladores/imunologia , Animais , Carcinoma Hepatocelular/genética , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Células Jurkat , Neoplasias Hepáticas/genética , Masculino , Camundongos Endogâmicos BALB C , MicroRNAs/genética , Linfócitos T Reguladores/efeitos dos fármacos
8.
Eur J Pharmacol ; 718(1-3): 41-7, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24070814

RESUMO

Glioblastoma is one of the most malignant brain tumors with a poor prognosis. In this study, we examined the effects of transferrin (Tf)-modified poly ethyleneglycol-poly lactic acid (PEG-PLA) nanoparticles conjugated with resveratrol (Tf-PEG-PLA-RSV) to glioma therapy in vitro and in vivo. The cell viability of Tf-PEG-PLA-RSV on C6 and U87 glioma cells was determined by the MTT assay. In vivo biodistribution and antitumor activity were investigated in Brain glioma bearing rat model of C6 glioma by i.p. administration of RSV-polymer conjugates. We found that the average diameter of each Tf-PEG-PLA-RSV is around 150 nm with 32 molecules of Tf on surface. In vitro cytotoxicity of PEG-PLA-RSV against C6 and U87 cells was higher than that of free RSV, and further the modification of Tf enhanced the cytotoxicity of the RSV-polymer conjugates as a result of the increased cellular uptake of the RSV-modified conjugates by glioma cells. In comparison with free RSV, RSV conjugates could significantly decrease tumor volume and accumulate in brain tumor, which resulted in prolonging the survival of C6 glioma-bearing rats. These results suggest that Tf-NP-RSV had a potential of therapeutic effect to glioma both in vitro and in vivo and might be a potential candidate for targeted therapy of glioma and worthy of further investigation.


Assuntos
Portadores de Fármacos/química , Glioma/patologia , Ácido Láctico/química , Polietilenoglicóis/química , Polímeros/química , Estilbenos/química , Estilbenos/farmacologia , Transferrina/química , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Transporte Biológico , Encéfalo/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glioma/tratamento farmacológico , Masculino , Terapia de Alvo Molecular , Nanopartículas/química , Poliésteres , Ratos , Resveratrol , Estilbenos/metabolismo , Estilbenos/farmacocinética , Análise de Sobrevida , Transferrina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Mol Cell Biochem ; 382(1-2): 137-43, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23793554

RESUMO

Resveratrol (RSV), a polyphenol, is known to play an important role in inhibiting proliferation and inducing apoptosis of glioma cells. The aim of this study was to explore the mechanism of RSV on U251 cells apoptosis. RSV showed a dose-dependent decrease in U251 cell viability. It could reduce IκB phosphorylation, nuclear P65 protein levels and NF-κB transcriptional activity, which suggested that signaling pathway are involved in RSV-induced apoptosis. In addition, RSV could inhibit miR-21 expression and down-regulation of miR-21 expression could suppress NF-κB activity. Interestingly, over-expression of miR-21 can reverse the effect of RSV on NF-κB activity and apoptosis in U251 cells. These results suggest that RSV can effectively induce apoptosis of U251 cells and modulation of miR-21 possibly contributes to this antitumor action.


Assuntos
MicroRNAs/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , MicroRNAs/genética , NF-kappa B/genética , Resveratrol , Transdução de Sinais/genética
10.
Dig Dis Sci ; 58(4): 1004-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23329013

RESUMO

BACKGROUND AND AIM: Nonalcoholic fatty liver disease (NAFLD) is strongly associated with obesity, hyperlipidemia, and type 2 diabetes mellitus. Several studies have found that fat mass and the obesity-associated (FTO) gene is linked to obesity. The aim of this work is to investigate the expression and function of FTO in liver with lipid metabolism diseases. METHODS: We investigated the basal FTO expression in an NAFLD rat model and compared it with control subjects. The function of FTO in lipid metabolism was further studied in L02 cells through overexpression experiments. RESULTS: A significant increase in FTO mRNA and protein levels was found in the NAFLD group. In addition, the FTO levels were positively associated with malondialdehyde and superoxide dismutase concentrations. FTO overexpression in L02 cells enhanced lipogenesis and oxidative stress. CONCLUSIONS: This study demonstrates that increased FTO levels in the liver are involved in oxidative stress and lipid deposition, which characterize NAFLD.


Assuntos
Gorduras na Dieta/farmacologia , Fígado Gorduroso/genética , Lipogênese/genética , Estresse Oxidativo/genética , Proteínas/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato , Animais , Peso Corporal , Dieta Hiperlipídica , Fígado Gorduroso/sangue , Fígado Gorduroso/patologia , Fígado/metabolismo , Fígado/patologia , Masculino , Tamanho do Órgão , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
11.
Protein Expr Purif ; 83(2): 169-76, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22503820

RESUMO

Heparinase I (HepA) was originally isolated from Flavobacterium heparinum (F. heparinum) and specifically cleaves heparin/heparan sulfate in a site-dependent manner, showing great promise for producing low molecular weight heparin (LMWH). However, expressing recombinant HepA is extremely difficult in Escherichia coli because it suffers from low yields, insufficient purity and insolubility. In this paper, we systematically cloned and fused the HepA gene to the C-terminus of five soluble partners, including translation initiation factor 2 domain I (IF2), glutathione S-transferase (GST), maltose-binding protein (MBP), small ubiquitin modifying protein (SUMO) and N-utilization substance A (NusA), to screen for their abilities to improve the solubility of recombinant HepA when expressed in E. coli. A convenient two-step immobilized metal affinity chromatography (IMAC) method was utilized to purify these fused HepA hybrids. We show that, except for NusA, the fusion partners dramatically improved the soluble expression of recombinant HepA, with IF2-HepA and SUMO-HepA creating almost completely soluble HepA (98% and 94% of expressed HepA fusions are soluble, respectively), which is the highest yield rate published to the best of our knowledge. Moreover, all of the fusion proteins show comparable biological activity to their unfused counterparts and could be used directly without removing the fusion tags. Together, our results provide a viable option to produce large amounts of soluble and active recombinant HepA for manufacturing.


Assuntos
Proteínas de Bactérias/química , Escherichia coli/metabolismo , Flavobacterium/enzimologia , Heparina Liase/química , Proteínas Recombinantes de Fusão/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Enteropeptidase/química , Enteropeptidase/genética , Enteropeptidase/metabolismo , Escherichia coli/genética , Flavobacterium/genética , Heparina Liase/genética , Heparina Liase/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Solubilidade
12.
Acta Radiol ; 52(10): 1147-54, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21969707

RESUMO

BACKGROUND: The apparent diffusion coefficient (ADC) from diffusion-weighted imaging (DWI) can quantify alterations in water diffusivity resulting from microscopic structural changes from amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD). PURPOSE: To investigate the ADC value for aMCI and AD using Brain Search (BS) software based on anatomical volumes of interest (AVOI). MATERIAL AND METHODS: In total, 174 aged people were screened, and 25 patients with AD, 26 patients with aMCI, and 18 normal controls (NCs) were recruited. DWI was performed at 1.5 T with a fluid-attenuated inversion recovery (FLAIR), and the independent ADC mapping was generated after imaging acquisition. Ninety regional parcellations were adopted in a Brain Search (BS) based on the automated anatomic labeling atlas. The gray scale intensities (water diffusivity) from the collected ADC mappings were analyzed with BS. The mean value of each anatomical brain region was compared among aMCI, AD, and NC. The statistically significant (P < 0.05) group differences are displayed in color. RESULTS: During the pathological process of AD, the changes of water diffusivity appeared first in the left hippocampus, then gradually progressed to the bilateral sides and eventually displayed right lateralization. The ADC values from aMCI were obviously elevated compared to the values from the NC group in the left limbic cortex. Between the AD and NC groups, the significantly different brain areas included the bilateral hippocampus, the Cingulum_Mid, the ParaHippocampal_R, and the Temporal and Frontal lobes. There was a negative correlation between the ADC values and the scores from MMSE, MoCA, the Digit test, Raven's IQ, and WAIS IQ. Additionally, the ADC values were positively correlated with the scores from CDR, ADL, and ADAS-Cog. CONCLUSION: The water diffusivity for aMCI and AD displays asymmetric anatomical lateralization. The water diffusivity alterations can be analyzed and visualized with our newly designed analytic imaging software, BS, which can be used as a good reference for examining and diagnosing aMCI and AD patients.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/patologia , Disfunção Cognitiva/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos , Idoso , Envelhecimento/patologia , Doença de Alzheimer/patologia , Amnésia , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos , Reprodutibilidade dos Testes , Software
13.
PLoS One ; 6(9): e24172, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21966359

RESUMO

AIMS: The extracellular pH of cancer cells is lower than the intracellular pH. Weakly basic anticancer drugs will be protonated extracellularly and display a decreased intracellular concentration. In this study, we show that copolymeric nanoparticles (NPs) are able to overcome this "pH-induced physiological drug resistance" (PIPDR) by delivering drugs to the cancer cells via endocytosis rather than passive diffussion. MATERIALS AND METHODS: As a model nanoparticle, Tetradrine (Tet, Pka 7.80) was incorporated into mPEG-PCL. The effectiveness of free Tet and Tet-NPs were compared at different extracellular pHs (pH values 6.8 and 7.4, respectively) by MTT assay, morphological observation and apoptotic analysis in vitro and on a murine model by tumor volume measurement, PET-CT scanning and side effect evaluation in vivo. RESULTS: The cytotoxicity of free Tet decreased prominently (P<0.05) when the extracellular pH decreased from 7.4 to 6.8. Meanwhile, the cytotoxicity of Tet-NPs was not significantly influenced by reduced pH. In vivo experiment also revealed that Tet-NPs reversed PIPDR more effectively than other existing methods and with much less side effects. CONCLUSION: The reversion of PIPDR is a new discovered mechanism of copolymeric NPs. This study emphasized the importance of cancer microenvironmental factors in anticancer drug resistance and revealed the superiority of nanoscale drug carrier from a different aspect.


Assuntos
Benzilisoquinolinas/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Nanopartículas/química , Neoplasias Experimentais/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Benzilisoquinolinas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Masculino , Camundongos , Camundongos Endogâmicos ICR , Neoplasias/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias Experimentais/química , Neoplasias Experimentais/patologia , Poliésteres/química , Polietilenoglicóis/química , Análise de Sobrevida , Carga Tumoral/efeitos dos fármacos
14.
Zhongguo Yi Liao Qi Xie Za Zhi ; 35(3): 164-8, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21954571

RESUMO

OBJECTIVE: To establish a brain functional network of the whole brain based on glucose metabolism, and to evaluate the cost and efficiency of the functional network. METHODS: 18F-FDG PET of 148 healthy volunteers (30-59 years, n = 148) was performed in a resting state. Images were registered to atlas by using the statistical parametric mapping (SPM) software. The functional connectivity between 90 cortical and sub-cortical regions was estimated by correlation analysis. RESULTS: Glucose metabolism brain functional networks had global efficiency greater than the lattice but less than the random graph, and local efficiency greater than random but less than lattice. This characteristically small-world behavior of the brain network was most consistently seen for low-cost to medium-cost networks. The small world regime was Cost-[0.0512, 0.5406]. The cost efficiency of the networks typically had a maximum positive value when the cost was 0.23. CONCLUSIONS: Glucose metabolism brain functional networks have economical small-world properties. It is feasible to analyze the functional characteristics of human brain by study 18F-FDG PET images. This paper provides a new method for studies on brain function.


Assuntos
Encéfalo/metabolismo , Glucose/metabolismo , Rede Nervosa , Tomografia por Emissão de Pósitrons/métodos , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos
15.
Protein Expr Purif ; 77(2): 185-92, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21292012

RESUMO

Ribonuclease inhibitor (RI) is a 50-kDa cytosolic scavenger of pancreatic-type ribonucleases which inhibits ribonucleolytic activity. Expression of recombinant RI is extremely difficult to reach high levels in soluble form in the cytoplasm of Escherichia coli. Here, we utilized five N-terminal fusion partners to improve the soluble expression of RI. Among these five fusion partners which have been screened, maltose-binding protein (MBP), N-utilization substance A (NusA) and translation initiation factor 2 domain I (IF2) have greatly improved the soluble expression level of recombinant murine RI under the drive of T7 promoter, while glutathione S-transferase (GST) and small ubiquitin modifying protein (SUMO) were much less efficient. All these RI-fusion proteins remained to be highly active in inhibiting RNase A activity. Furthermore, all fusion tags can be efficiently removed by enterokinase digestion to generate native RI which results the highest yield to date (>30mg of native RI per liter culture). And a convenient two-step immobilized metal affinity chromatography (IMAC) method has been implemented in our study, comparing with the traditional RNase A affinity chromatography method.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas Ligantes de Maltose/metabolismo , Fatores de Alongamento de Peptídeos/metabolismo , Fator de Iniciação 2 em Procariotos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Cromatografia de Afinidade , Clonagem Molecular , Enteropeptidase/metabolismo , Inibidores Enzimáticos/isolamento & purificação , Escherichia coli , Proteínas de Escherichia coli/genética , Expressão Gênica , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Proteínas Ligantes de Maltose/genética , Camundongos , Dados de Sequência Molecular , Fatores de Alongamento de Peptídeos/genética , Fator de Iniciação 2 em Procariotos/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Ribonuclease Pancreático/antagonistas & inibidores , Ribonuclease Pancreático/metabolismo , Proteína SUMO-1/genética , Proteína SUMO-1/metabolismo , Solubilidade , Fatores de Transcrição/genética , Fatores de Elongação da Transcrição
16.
J Control Release ; 142(3): 438-46, 2010 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-19896997

RESUMO

Paclitaxel (PTX)-loaded poly(N-vinylpyrrolidone)-b-poly(epsilon-caprolactone) (PVP-b-PCL) nanoparticles with high drug payload were successfully prepared by a modified nano-precipitation method and characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), dynamic light scattering (DLS) and zeta potential. The satisfactory drug loading content (>25%) and high encapsulation efficiency (>85%) were achieved. The in vivo real-time biodistribution of PTX-loaded nanoparticles was investigated using near-infrared fluorescence (NIRF) imaging. The antitumor effect of PTX-loaded nanoparticles was evaluated, both, in vitro on three different cancer cell lines and in vivo on hepatic H22 tumor bearing mice model via intravenous administration (i.v.). It is found that PTX-loaded nanoparticles exhibit significant superior in vivo antitumor effect than the commercially available Taxol formulation by combining the tumor volumes and survival rates measurement, intravital positron emission tomography and computed tomography (PET/CT) imaging.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Portadores de Fármacos/química , Nanopartículas/química , Paclitaxel/administração & dosagem , Poliésteres/química , Povidona/análogos & derivados , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/síntese química , Composição de Medicamentos , Luz , Masculino , Camundongos , Camundongos Endogâmicos ICR , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Paclitaxel/uso terapêutico , Tamanho da Partícula , Poliésteres/síntese química , Tomografia por Emissão de Pósitrons , Povidona/síntese química , Povidona/química , Espalhamento de Radiação , Espectroscopia de Luz Próxima ao Infravermelho , Propriedades de Superfície , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Eur J Pharm Biopharm ; 70(3): 726-34, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18634874

RESUMO

cis-Dichlorodiamminoplatinum (II) (cisplatin) has demonstrated extraordinary activities against a variety of solid tumors. However, the clinical efficacy is contrasted by its toxicity profile. To reduce the toxicity and enhance the circulation time of cisplatin, core-shell structure nanoparticles were prepared from block copolymer of methoxy poly(ethylene glycol)-polycaprolactone (mPEG-PCL). Cisplatin was incorporated into the nanoparticles with high encapsulation efficiency more than 75%. Controlled release of cisplatin was observed in a sustained manner. In vitro cytotoxicity studies proved the efficacy of cisplatin-loaded nanoparticles against BGC823 and H(22) cells in a dose and time-dependent manner. Furthermore, intratumoral administration was applied to improve the tumor-targeted delivery in the in vivo evaluation. Compared with free cisplatin, cisplatin-loaded nanoparticles exhibited superior antitumor effect by delaying tumor growth when delivered intratumorally, while no significant improvement was observed when they were administrated intraperitoneally. Positron emission tomography/computed tomography (PET/CT) imaging was utilized for the first time to detect the declined (18)F-labeled 2-fluoro-2-deoxy-d-glucose ((18)F-FDG) uptake of the tumor in mice receiving cisplatin-loaded nanoparticles intratumorally. These results suggest that polymeric nanoparticles with core-shell structures are promising for further studies as drug delivery carriers, and intratumoral delivery of drug-loaded nanoparticles could be a probable clinically useful therapeutic regimen.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Portadores de Fármacos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Nanopartículas , Poliésteres/química , Polietilenoglicóis/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Cisplatino/administração & dosagem , Cisplatino/química , Cisplatino/metabolismo , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Composição de Medicamentos , Humanos , Injeções Intralesionais , Injeções Intraperitoneais , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Camundongos , Camundongos Endogâmicos ICR , Tomografia por Emissão de Pósitrons , Solubilidade , Fatores de Tempo , Tomografia Computadorizada por Raios X , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Zhonghua Yi Xue Za Zhi ; 87(39): 2777-9, 2007 Oct 23.
Artigo em Chinês | MEDLINE | ID: mdl-18167271

RESUMO

OBJECTIVE: To study the change of cerebral metabolism rate of glucose (CMRglc) of cerebral white matter in Alzheimer's Disease. METHODS: Positron emission tomography (PET) was performed on 13 AD patients, 6 with behavioral and psychological symptoms of dementia (BPSD) and 7 without BPSD, and 10 healthy controls. The regional cerebral metabolism of glucose (rCMRglc) of some brain regions and nuclei were detected. RESULTS: (1) The rCMRglc of the cerebral white matter decreased extensively in the AD patients, especially in the right frontal lobe, superior gyrus of the left frontal lobe (P = 0.001). (2) The rCMRglc of subcortical white matter of the left medial prefrontal lobe and the left cuneus of occipital lobe increased in the AD patients. (3) The levels of rCMRglc of the subcortical white matter of both side middle occipital lobe, left cuneus of occipital lobe, right inferior parietal lobule, left fusiform gyrus of temporal lobe and the left medial prefrontal lobe were all significantly higher in the AD patients with BPSD than in those without BPSD (P = 0.001). While the levels of rCMRglc of the subcortical white matter of both side paracentral lobule, right superior and middle frontal lobe, and left superior temporal lobe were all significantly lower in the AD patients with BPSD than in those without BPSD (all P = 0.001). CONCLUSION: There is diffuse abnormal rCMRglc in the cerebral white matter in the AD patients: the rCMRglc decreases in the frontal-temporal-occipital association area, and the rCMRglc of the medial prefrontal lobe and cuneus of occipital lobe increases. BPSD is correlated with the abnormal metabolism of related cerebral regions.


Assuntos
Doença de Alzheimer/metabolismo , Córtex Cerebral/metabolismo , Glucose/metabolismo , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Software
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