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1.
Hepatology ; 67(2): 586-599, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28646552

RESUMO

Several strategies to improve the efficacy of radiation therapy against hepatocellular carcinoma (HCC) have been investigated. One approach is to develop radiosensitizing compounds. Because histone deacetylase 4 (HDAC4) is highly expressed in liver cancer and known to regulate oncogenesis through chromatin structure remodeling and controlling protein access to DNA, we postulated that HDAC4 inhibition might enhance radiation's effect on HCC cells. HCC cell lines (Huh7 and PLC5) and an ectopic xenograft were pretreated with HDAC inhibitor or short hairpin RNA to knock down expression of HDAC4 and then irradiated (2.5-10.0 Gy). We evaluated cell survival by a clonogenic assay; apoptosis by Annexin V immunofluorescence; γH2AX, Rad51, and HDAC4 by immunofluorescence staining; HDAC4, Rad51, and ubiquitin-conjugating enzyme 9 (Ubc9) in HCC cell nuclei by cell fractionation and confocal microscopy; physical interaction between HDAC4/Rad51/Ubc9 by immunoprecipitation; and the downstream targets of HDAC4 knockdown by immunoblotting. Both HDAC4 knockdown and HDAC inhibitor enhanced radiation-induced cell death and reduced homologous recombination repair of DNA double-strand breaks and protein kinase B activation, leading to increased apoptosis. HDAC4 knockdown with or without an HDAC inhibitor significantly delayed tumor growth in a radiation-treated xenograft model. Radiation stimulated nuclear translocation of Rad51 in an HDAC4-dependent manner and the binding of Ubc9 directly to HDAC4, which led to Ubc9 acetylation. Moreover, these effects were accompanied by HDAC4/Ubc9/Rad51 complex dissociation through inhibiting nuclear translocation. Conclusion: HDAC4 signaling blockade enhances radiation-induced lethality in HCC cells and xenografts. These findings raise the possibility that HDAC4/Ubc9/Rad51 complex in DNA repair may be a target for radiosensitization of HCC. (Hepatology 2018;67:586-599).


Assuntos
Carcinoma Hepatocelular/radioterapia , Reparo do DNA/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Neoplasias Hepáticas/radioterapia , Radiossensibilizantes/farmacologia , Proteínas Repressoras/antagonistas & inibidores , Enzimas de Conjugação de Ubiquitina/antagonistas & inibidores , Transporte Ativo do Núcleo Celular , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/metabolismo , Humanos , Masculino , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Rad51 Recombinase/antagonistas & inibidores , Proteínas Repressoras/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Zhongguo Zhong Yao Za Zhi ; 42(11): 2046-2051, 2017 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-28822146

RESUMO

DNA marked-assisted selection of medicinal plants accelerated the breeding and promotion of new cultivars, and guaranteed the healthy development of Chinese medicinal materials industry. The first disease-resistant cultivar of notoginseng, namely "Miaoxiang Kangqi 1", served as the object of study. We evaluated the Kangqi's resistance of seeds, seedlings and root against the pathological bacteria (Fusarum oxysporum) of root rot. Compared to the traditional cultivars, the disease index of notoginseng seeds declined by 52.0% after inoculation for seven days; the death rate of seedlings and disease index of root respectively decreased by 72.1% and 62.4% after inoculation for 25 days. Additionally, the growth inhibition ratio of notoginseng seeds and seedlings declined after inoculation. The seeds, seedlings and roots of "Miaoxiang Kangqi 1" showed significantly resistant to root rot. The evaluation of disease-resistance of Kangqi provided the basis for the popularization of new cultivar and guaranteed the favoring conduct of notoginseng pollution-free cultivation.


Assuntos
Resistência à Doença/genética , Marcadores Genéticos , Panax notoginseng/genética , Plantas Medicinais/genética , Panax notoginseng/crescimento & desenvolvimento , Melhoramento Vegetal , Doenças das Plantas , Raízes de Plantas , Plantas Medicinais/crescimento & desenvolvimento
3.
Zhongguo Zhong Yao Za Zhi ; 42(1): 56-62, 2017 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-28945025

RESUMO

DNA marker-assisted selection of medicinal plants is based on the DNA polymorphism, selects the DNA sequences related to the phenotypes such as high yields, superior quality, stress-resistance and so on according to the technologies of molecular hybridization, polymerase chain reaction and high-throughput sequencing, and assists the breeding of new cultivars. This study bred the first disease-resistant cultivar of notoginseng "Miaoxiang Kangqi 1" using the technology of DNA marker-assisted selection of medicinal plants and systematic breeding. The disease-resistant cultivar of notoginseng contained 12 special SNPs based on the analysis of Restriction-site Associated DNA Sequencing (RAD-Seq). Among the SNP (record_519688) was related to the root rot-resistant characteristics, which indicated this SNP could serve as genetic markers of disease-resistant cultivars and assist the systematic breeding. Compared to the conventional cultivated cultivars, the incidence rate of root-rot and rust-rot in notoginseng seedlings decreased by 83.6% and 71.8%, respectively. The incidence rate of root-rot respectively declined by 43.6% and 62.9% in notoginseng cultivation for 2 and 3 years compared with those of the conventional cultivated cultivars. Additionally, the potential disease-resistant groups were screened based on the relative SNP, and this model enlarged the target groups and advanced the breeding efficiency. DNA marker-assisted selection of medicinal plants accelerated the breeding and promotion of new cultivars, and guaranteed the healthy development of Chinese medicinal materials industry.


Assuntos
Resistência à Doença/genética , Marcadores Genéticos , Panax notoginseng/genética , Melhoramento Vegetal , Doenças das Plantas/genética , Plantas Medicinais/genética , Polimorfismo de Nucleotídeo Único , Seleção Genética , Análise de Sequência de DNA
4.
J Gastroenterol Hepatol ; 30(8): 1317-24, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25682950

RESUMO

BACKGROUND AND AIM: Sonic Hedgehog (SHH) is a regulator in tumorigenesis of hepatocellular carcinoma (HCC). This study aimed to determine whether radiation-induced SHH signaling occurs in HCC and whether SHH inhibitor acts as a radiosensitizer. METHODS: The in vitro effects of combining SHH ligand (recombinant human SHH) or inhibitor (cyclopamine) with irradiation were evaluated in the human HCC cell lines, Huh-7 and PLC/PRF/5, and murine cell line BNL. Cell survival and apoptosis were measured using a colony formation assay, annexin-V staining, and poly (ADP-ribose) polymerase activation. Western blotting and immunofluorescence staining were used to detect protein expression. The in vivo response to radiotherapy and/or cyclopamine was tested in BALB/c mice bearing an orthotopic allogeneic tumor. RESULTS: Treatment of HCC cells with irradiation and SHH ligand had a protective effect on clonogenic cell survival. Treatment with irradiation and cyclopamine was a more potent inhibitor of cell proliferation than either modality alone. The antiproliferative activity of cyclopamine was attributable to apoptosis induction. Radiation dose-dependently upregulated the expression of Gli-1 (a transcription factor induced by SHH), and this effect was observed mainly in the nucleus. When combined with cyclopamine, irradiation inhibited Gli-1 and increased DNA double-strand breakage. Radiotherapy increased SHH and Gli-1 expression in allogeneic tumor. When compared with radiotherapy alone, cyclopamine with radiotherapy reduced the mean tumor size of orthotopic tumors by 67% (P < 0.05). CONCLUSION: Combining an SHH inhibitor with radiotherapy may enhance HCC cell and orthotopic tumor radiosensitivity.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/radioterapia , Proteínas Hedgehog/antagonistas & inibidores , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/radioterapia , Terapia de Alvo Molecular , Tolerância a Radiação/efeitos dos fármacos , Tolerância a Radiação/genética , Radiossensibilizantes/farmacologia , Radiossensibilizantes/uso terapêutico , Alcaloides de Veratrum/farmacologia , Alcaloides de Veratrum/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/fisiopatologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Terapia Combinada , Quebras de DNA de Cadeia Dupla , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Expressão Gênica/efeitos da radiação , Humanos , Ligantes , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/fisiopatologia , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Proteínas Recombinantes , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Fatores de Transcrição , Proteína GLI1 em Dedos de Zinco
5.
Int J Cancer ; 135(2): 492-501, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24375034

RESUMO

Radiotherapy has been integrated into the multimodal treatment of hepatocellular carcinoma (HCC), especially of localized hepatic tumor(s) refractory to conventional treatment. However, tumor control remains unsatisfactory mainly because of insufficient dose, and sublethally irradiated tumor may associate with metastasis. Our aim was to assess the effect of combining a molecularly targeted Aurora kinase inhibitor, VE-465, with radiotherapy in in vitro and in vivo models of human HCC. Human HCC cell lines (Huh7 and PLC-5) were used to evaluate the in vitro synergism of combining VE-465 with irradiation. Flow cytometry analyzed the cell cycle changes, while western blot investigated the protein expressions after the combined treatment. Severe combined immunodeficient (SCID) mice bearing ectopic and orthotopic HCC xenografts were treated with VE-465 and/or radiotherapy for the in vivo response. VE-465 significantly enhanced radiation-induced death in HCC cells by a mechanism involving the enhanced inhibition of histone H3 phosphorylation and interruption of cell cycle change. In SCID, mice bearing ectopic HCC xenografts, pretreatment with VE-465 (20 mg/kg/day × 9 days) significantly enhanced the tumor-suppressive effect of radiotherapy (5 Gy/day × 5 days) by 54.0%. A similar combinatorial effect of VE-465 and radiotherapy was observed in an orthotopic model of Huh7 tumor growth by 17.2%. In the orthotopic Huh7 xenografts, VE-465 significantly enhanced radiation-induced tumor growth suppression by a mechanism involving the increased apoptosis. VE-465 is a potent inhibitor of Aurora kinase with therapeutic value as a radiosensitizer of HCC.


Assuntos
Aurora Quinases/antagonistas & inibidores , Carcinoma Hepatocelular/patologia , Ciclo Celular , Neoplasias Hepáticas/patologia , Piperazinas/farmacologia , Radiossensibilizantes/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Western Blotting , Carcinoma Hepatocelular/enzimologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Imunofluorescência , Humanos , Neoplasias Hepáticas/enzimologia , Masculino , Camundongos , Camundongos SCID , Inibidores de Proteínas Quinases/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Microcirculation ; 21(2): 178-86, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25279428

RESUMO

OBJECTIVE: AGEs induce endothelial cell dysfunction in HUVECs, resulting in ROS production and triggering apoptosis. This study sought to identify miRNAs involved in AGE-induced endothelial cell injury. METHODS: Microarray analysis to identify miRNAs altered with AGE stimulation was undertaken, and results were confirmed using real-time quantitative polymerase chain reaction. The interaction of miRNAs with the RhoA and ROCK2 genes was confirmed using luciferase assays, and their effects on expression were determined using Western blot analysis. The effects of AGEs and miRNAs on endothelial cell permeability were assessed. RESULTS: AGEs induced ROS production and apoptosis of HUVECs (p < 0.05). AGE-induced miR-200b and miR-200c downregulation led to increased expression of their target genes, RhoA and ROCK, respectively. AGE-induced endothelial cell permeability and F-actin expression were significantly reduced with both miR-200b and miR-200c mimics (p < 0.05). Furthermore, AGE-induced stress fiber formation was reduced in cells treated with miR-200b mimics. CONCLUSION: miR-200b and miR-200c are suppressed in AGE-induced endothelial cell injury, resulting in unregulated RhoA/ROCK2 signaling. Further studies are necessary to evaluate the therapeutic value of targeting miRNAs or their target genes for treatment of vascular diseases.


Assuntos
Permeabilidade Capilar , Produtos Finais de Glicação Avançada/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , MicroRNAs/metabolismo , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Apoptose/efeitos dos fármacos , Produtos Finais de Glicação Avançada/farmacologia , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos
7.
Phytomedicine ; 119: 154947, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37549536

RESUMO

BACKGROUND: Bladder cancer (BC) is a challenging disease to manage. Researchers have been investigating the potential of magnolol, a compound derived from Magnolia officinalis, as an anti-cancer agent. However, the exact regulatory mechanism of magnolol and its impact on the NF-κB signaling pathway in BC remain unclear. MATERIALS: To comprehensively evaluate its therapeutic potential, the researchers conducted a series of experiments using BC cell lines (TSGH8301, T24, and MB49) and in vivo animal models. RESULTS: The results of the study demonstrated that magnolol exhibits cytotoxic effects on BC cells by activating both the extrinsic and intrinsic apoptosis signaling pathways. Additionally, the expression of anti-apoptotic genes was downregulated by magnolol treatment. The researchers also uncovered the regulatory role of PKCδ/ERK and miR-124-3p in the NF-κB pathway, which may be influenced by magnolol. Treatment with magnolol led to the inactivation of PKCδ/ERK and an increase in miR-124-3p expression, effectively inhibiting NF-κB-mediated progression of BC. Importantly, the administration of magnolol did not result in significant toxicity in normal tissues, highlighting its potential as a safe adjunctive therapy with minimal adverse effects. CONCLUSION: These findings position magnolol as a promising therapeutic agent for the treatment of BC. By activating apoptosis signaling pathways and inhibiting NF-κB pathway through the upregulation of miR-124-3p and downregulation of PKCδ/ERK activation, magnolol holds promise for suppressing tumor progression and improving patient outcomes in BC. Further research and clinical trials are warranted to explore the full potential of magnolol in the future.


Assuntos
Lignanas , MicroRNAs , Neoplasias da Bexiga Urinária , Animais , NF-kappa B/metabolismo , Lignanas/farmacologia , Lignanas/uso terapêutico , MicroRNAs/genética , Compostos de Bifenilo/farmacologia , Proliferação de Células , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Linhagem Celular Tumoral , Apoptose
8.
Neural Regen Res ; 17(11): 2381-2390, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35535875

RESUMO

Blood exosomes, which are extracellular vesicles secreted by living cells into the circulating blood, are regarded as a relatively noninvasive novel tool for monitoring brain physiology and disease states. An increasing number of blood cargo-loaded exosomes are emerging as potential biomarkers for preclinical and clinical Alzheimer's disease. Therefore, we conducted a meta-analysis and systematic review of molecular biomarkers derived from blood exosomes to comprehensively analyze their diagnostic performance in preclinical Alzheimer's disease, mild cognitive impairment, and Alzheimer's disease. We performed a literature search in PubMed, Web of Science, Embase, and Cochrane Library from their inception to August 15, 2020. The research subjects mainly included Alzheimer's disease, mild cognitive impairment, and preclinical Alzheimer's disease. We identified 34 observational studies, of which 15 were included in the quantitative analysis (Newcastle-Ottawa Scale score 5.87 points) and 19 were used in the qualitative analysis. The meta-analysis results showed that core biomarkers including Aß1-42, P-T181-tau, P-S396-tau, and T-tau were increased in blood neuron-derived exosomes of preclinical Alzheimer's disease, mild cognitive impairment, and Alzheimer's disease patients. Molecules related to additional risk factors that are involved in neuroinflammation (C1q), metabolism disorder (P-S312-IRS-1), neurotrophic deficiency (HGF), vascular injury (VEGF-D), and autophagy-lysosomal system dysfunction (cathepsin D) were also increased. At the gene level, the differential expression of transcription-related factors (REST) and microRNAs (miR-132) also affects RNA splicing, transport, and translation. These pathological changes contribute to neural loss and synaptic dysfunction. The data confirm that the above-mentioned core molecules and additional risk-related factors in blood exosomes can serve as candidate biomarkers for preclinical and clinical Alzheimer's disease. These findings support further development of exosome biomarkers for a clinical blood test for Alzheimer's disease. This meta-analysis was registered at the International Prospective Register of Systematic Reviews (Registration No. CRD4200173498, 28/04/2020).

9.
Br J Nutr ; 106(9): 1330-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21733323

RESUMO

Medium-chain fatty acids (MCFA) are widely used in diets for patients with obesity. To develop a delivery system for suppressing dietary fat accumulation into adipose tissue, MCFA were encapsulated in nanoliposomes (NL), which can overcome the drawbacks of MCFA and keep their properties unchanged. In the present study, crude liposomes were first produced by the thin-layer dispersion method, and then dynamic high-pressure microfluidisation (DHPM) and DHPM combined with freeze-thawing methods were used to prepare MCFA NL (NL-1 and NL-2, respectively). NL-1 exhibited smaller average size (77.6 (SD 4.3) nm), higher zeta potential (- 40.8 (SD 1.7) mV) and entrapment efficiency (73.3 (SD 16.1) %) and better stability, while NL-2 showed narrower distribution (polydispersion index 0.193 (SD 0.016)). The body fat reduction property of NL-1 and NL-2 were evaluated by short-term (2 weeks) and long-term (6 weeks) experiments of mice. In contrast to the MCFA group, the NL groups had overcome the poor palatability of MCFA because the normal diet of mice was maintained. The body fat and total cholesterol (TCH) of NL-1 (1.54 (SD 0.30) g, P = 0.039 and 2.33 (SD 0.44) mmol/l, P = 0.021, respectively) and NL-2 (1.58 (SD 0.69) g, P = 0.041 and 2.29 (SD 0.38) mmol/l, P = 0.015, respectively) significantly decreased when compared with the control group (2.11 (SD 0.82) g and 2.99 (SD 0.48) mmol/l, respectively). The TAG concentration of the NL-1 group (0.55 (SD 0.14) mmol/l) was remarkably lower (P = 0.045) than the control group (0.94 (SD 0.37) mmol/l). No significant difference in weight and fat gain, TCH and TAG was detected between the MCFA NL and MCFA groups. Therefore, MCFA NL could be potential nutritional candidates for obesity to suppress body fat accumulation.


Assuntos
Tecido Adiposo/metabolismo , Gorduras na Dieta/metabolismo , Ácidos Graxos/administração & dosagem , Metabolismo dos Lipídeos , Lipídeos/sangue , Nanotecnologia/métodos , Obesidade/tratamento farmacológico , Animais , Colesterol/sangue , Ácidos Graxos/metabolismo , Ácidos Graxos/uso terapêutico , Lipossomos , Masculino , Camundongos , Camundongos Endogâmicos , Obesidade/metabolismo , Paladar , Triglicerídeos/sangue
10.
Anticancer Res ; 41(1): 123-130, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33419805

RESUMO

BACKGROUND/AIM: Non-small cell lung cancer (NSCLC) is a serious disease and the leading cause of death globally. Overexpression of protein kinase B/nuclear factor-kappa B (NF-κB) signaling transduction of NSCLC cells was recognized as a potential therapeutic target. Lenvatinib is a multiple kinase inhibitor against vascular endothelial growth factor receptor family. However, whether lenvatinib may affect AKT/NF-κB in NSCLC remains unknown. MATERIALS AND METHODS: MTT assay, NF-κB reporter gene assay, flow cytometry, tranwell migration/invasion analysis and western blotting were used to identify the alteration of cell viability, NF-κB activation, apoptosis effect, migration/invasion potential and AKT/NF-κB related protein expression, respectively, in CL-1-5-F4 cells after lenvatinib treatment. RESULTS: The cell viability and NF-κB activity were suppressed by lenvatinib. Extrinsic and intrinsic apoptosis were activated by lenvatinib. Additionally, the metastatic potential of CL-1-5-F4 cells was also suppressed by lenvatinib. CONCLUSION: Altogether, lenvatinib induced extrinsic/intrinsic apoptosis and suppressed migration/invasion ability of NSCLC cells that was associated with AKT/NF-κB signaling inactivation.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , NF-kappa B/metabolismo , Compostos de Fenilureia/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinolinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos/farmacologia , Biomarcadores Tumorais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Humanos , Inibidores de Proteínas Quinases/farmacologia
11.
Polymers (Basel) ; 13(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799623

RESUMO

RNA-based molecules have recently become hot candidates to be developed into therapeutic agents. However, successful applications of RNA-based therapeutics might require suitable carriers to protect the RNA from enzymatic degradation by ubiquitous RNases in vivo. Because of their better biocompatibility and biodegradability, protein-based nanoparticles are considered to be alternatives to their synthetic polymer-based counterparts for drug delivery. Hepatitis C virus (HCV) core protein has been suggested to be able to self-assemble into nucleocapsid-like particles in vitro. In this study, the genomic RNA-binding domain of HCV core protein consisting of 116 amino acids (p116) was overexpressed with E. coli for investigation. The recombinant p116 was able to assemble into particles with an average diameter of approximately 27 nm, as visualized by electron microscopy and atomic force microscopy. Measurements with fluorescence spectroscopy, flow cytometry, and fluorescence quenching indicated that the p116-assembled nanoparticles were able to encapsulate small anionic molecules and structured RNA. This study demonstrates methods that exploit the self-assembly nature of a virus-derived protein for nanoparticle production. This study also suggests that the virus-derived protein-assembled particles could possibly be developed into potential carriers for anionic molecular drugs and structured RNA-based therapeutics.

12.
Neurotherapeutics ; 18(2): 1064-1080, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33786807

RESUMO

Brain capillaries are crucial for cognitive functions by supplying oxygen and other nutrients to and removing metabolic wastes from the brain. Recent studies have demonstrated that constriction of brain capillaries is triggered by beta-amyloid (Aß) oligomers via endothelin-1 (ET1)-mediated action on the ET1 receptor A (ETRA), potentially exacerbating Aß plaque deposition, the primary pathophysiology of Alzheimer's disease (AD). However, direct evidence is still lacking whether changes in brain capillaries are causally involved in the pathophysiology of AD. Using APP/PS1 mouse model of AD (AD mice) relative to age-matched negative littermates, we identified that reductions of density and diameter of hippocampal capillaries occurred from 4 to 7 months old while Aß plaque deposition and spatial memory deficit developed at 7 months old. Notably, the injection of ET1 into the hippocampus induced early Aß plaque deposition at 5 months old in AD mice. Conversely, treatment of ferulic acid against the ETRA to counteract the ET1-mediated vasoconstriction for 30 days prevented reductions of density and diameter of hippocampal capillaries as well as ameliorated Aß plaque deposition and spatial memory deficit at 7 months old in AD mice. Thus, these data suggest that reductions of density and diameter of hippocampal capillaries are crucial for initiating Aß plaque deposition and spatial memory deficit at the early stages, implicating the development of new therapies for halting or curing memory decline in AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Precursor de Proteína beta-Amiloide , Capilares/efeitos dos fármacos , Disfunção Cognitiva/tratamento farmacológico , Ácidos Cumáricos/administração & dosagem , Presenilina-1 , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Capilares/patologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/patologia , Hipocampo/irrigação sanguínea , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Injeções Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Presenilina-1/genética
13.
Environ Manage ; 43(1): 166-88, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19015828

RESUMO

Some countries, including Taiwan, have adopted strategic environmental assessment (SEA) to assess and modify proposed policies, plans, and programs (PPPs) in the planning phase for pursuing sustainable development. However, there were only some sketchy steps focusing on policy assessment in the system of Taiwan. This study aims to develop a methodology for SEA in Taiwan to enhance the effectiveness associated with PPPs. The proposed methodology comprises an SEA procedure involving PPP management and assessment in various phases, a sustainable assessment framework, and an SEA management system. The SEA procedure is devised based on the theoretical considerations by systems thinking and the regulative requirements in Taiwan. The positive and negative impacts on ecology, society, and economy are simultaneously considered in the planning (including policy generation and evaluation), implementation, and control phases of the procedure. This study used the analytic hierarchy process, Delphi technique, and systems analysis to develop a sustainable assessment framework. An SEA management system was built based on geographic information system software to process spatial, attribute, and satellite image data during the assessment procedure. The proposed methodology was applied in the SEA of golf course installation policy in 2001 as a case study, which was the first SEA in Taiwan. Most of the 82 existing golf courses in 2001 were installed on slope lands and caused a serious ecological impact. Assessment results indicated that 15 future golf courses installed on marginal lands (including buffer zones, remedied lands, and wastelands) were acceptable because the comprehensive environmental (ecological, social, and economic) assessment value was better based on environmental characteristics and management regulations of Taiwan. The SEA procedure in the planning phase for this policy was completed but the implementation phase of this policy was not begun because the related legislation procedure could not be arranged due to a few senators' resistance. A self-review of the control phase was carried out in 2006 using this methodology. Installation permits for 12 courses on slope lands were terminated after 2001 and then 27 future courses could be installed on marginal lands. The assessment value of this policy using the data on ecological, social, and economic conditions from 2006 was higher than that using the data from 2001. The analytical results illustrate that the proposed methodology can be used to effectively and efficiently assist the related authorities for SEA.


Assuntos
Conservação dos Recursos Naturais/métodos , Planejamento Ambiental , Meio Ambiente , Golfe , Formulação de Políticas , Sistemas de Informação Geográfica , Gestão da Informação/métodos , Taiwan
14.
Glia ; 56(13): 1390-400, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18618653

RESUMO

Reactive gliosis caused by post-traumatic injury often results in marked expression of chondroitin sulfate proteoglycan (CSPG), which inhibits neurite outgrowth and regeneration. Methylprednisolone (MP), a synthetic glucocorticoid, has been shown to have neuroprotective and anti-inflammatory effects for the treatment of acute spinal cord injury (SCI). However, the effect of MP on CSPG expression in reactive glial cells remains unclear. In our study, we induced astrocyte reactivation using alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) and cyclothiazide to mimic the excitotoxic stimuli of SCI. The expression of glial fibrillary acidic protein (GFAP), a marker of astrocyte reactivation, and CSPG neurocan and phosphacan were significantly elevated by AMPA treatment. The conditioned media from AMPA-treated astrocytes strongly inhibited neurite outgrowth of rat dorsal root ganglion neurons, and this effect was reversed by pretreatment with MP. Furthermore, MP downregulated GFAP and CSPG expression in adult rats with SCI. Additionally, both the glucocorticoid receptor (GR) antagonist RU486 and GR siRNA reversed the inhibitory effects of MP on GFAP and neurocan expression. Taken together, these results suggest that MP may improve neuronal repair and promote neurite outgrowth after excitotoxic insult via GR-mediated downregulation of astrocyte reactivation and inhibition of CSPG expression.


Assuntos
Astrócitos/efeitos dos fármacos , Astrócitos/fisiologia , Proteoglicanas de Sulfatos de Condroitina/antagonistas & inibidores , Proteoglicanas de Sulfatos de Condroitina/biossíntese , Proteína Glial Fibrilar Ácida/antagonistas & inibidores , Proteína Glial Fibrilar Ácida/biossíntese , Metilprednisolona/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Proteoglicanas de Sulfatos de Condroitina/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Proteína Glial Fibrilar Ácida/genética , Ratos , Ratos Sprague-Dawley
15.
J Clin Med ; 7(8)2018 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-30096934

RESUMO

Disseminated peritoneal leiomyomatosis (DPL) is a rare condition that is characterized by the presence of multiple subperitoneal or peritoneal smooth muscle nodules of varying sizes on the omentum and peritoneal surfaces, grossly mimicking disseminated carcinoma. DPL usually develops in premenopausal women with a benign course, and it is often found incidentally during abdominal surgery. Malignant transformation is a rare clinical course of DPL. Only a few studies have focused on DPL transformation into a leiomyosarcoma. Herein, we describe the case of a 61-year-old woman with a history of recurrent leiomyoma of the uterus who presented with intermittent progressive abdominal pain. The imaging study revealed a huge heterogeneous density mass in the pelvic region with pulmonary and hepatic metastases. Exploratory laparotomy and debulking surgery were performed, and showed the coexistence of DPL and leiomyosarcoma. She died approximately one month after the diagnosis because of rapid progression of pleural effusion due to malignancy. This case highlights the clinical features of DPL and its malignant transformation and metastasis so physicians can make an early diagnosis and provide timely management.

16.
Gene ; 669: 63-68, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-29800734

RESUMO

To explore the role of genetic factors in the pathogenesis of hypertension, our study investigated the gender-specific association between four polymorphisms in the Apelin/APJ gene and hypertension risk in southeastern Chinese population. All participants including 645 hypertensive patients and 362 normotensive controls were genotyped for 4 gene polymorphisms associated with hypertension susceptibility including Apelin (rs909656, rs5975126) and APJ (rs10501367, rs11544374). According to genotype analysis, for male subjects, the frequencies of genotypes (P = 0.046 and 0.046, respectively) of rs10501367 and rs11544374 revealed significant differences between the hypertension and control groups. Moreover, for female subjects, there was significant difference on the genotype distribution of rs11544374 between two groups (P = 0.046). The association of rs10501367 with hypertension was significant for males under additive models and recessive models, even after adjusting for age, BMI, fasting glucose and waistline. Besides, significant association was observed for rs11544374 in females under additive models. As for haplotype analysis, haplotype T-A (in order of rs10501367 and rs11544374) in APJ gene was marginally overrepresented in controls (17.9%) compared to patients with hypertension (11.6%) in males (P = 0.003). The mutation of polymorphism rs10501367 in APJ gene decreased risk of hypertension in Chinese males.


Assuntos
Receptores de Apelina/genética , Apelina/genética , Hipertensão/genética , Adulto , Idoso , Pressão Sanguínea/genética , Estudos de Casos e Controles , China , Feminino , Haplótipos , Humanos , Hipertensão/diagnóstico , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Fatores de Risco , Fatores Sexuais
17.
Sci Total Environ ; 354(1): 1-19, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16242756

RESUMO

Air quality monitoring data are important bases for air quality management strategies planning and performance assessment. Therefore, the environmental protection authorities need to plan the air quality monitoring network effectively. However, in Taiwan, the national Environmental Protection Administration (EPA) and some county environmental protection bureaus (EPB) separately installed their own monitoring stations. This study developed an integrated methodology and computer system for planning air quality monitoring networks. The environmental, social, and economic objectives and sub-objectives, and their weights were identified using system analysis and multiple objective planning, based on the principles of sustainable development. A multiple objective optimization model and procedure for sustainable air quality monitoring networks planning are developed in this study. According to the procedure, a multiple objective planning system for sustainable air quality monitoring networks (MOPSSAQMN) is developed using computer software based on the modified bounded implicit enumeration algorithm with the constraint arrangement method. The air quality monitoring network of Taoyuan County, in northern Taiwan, was used as a case study to demonstrate the proposed method. Two satisfactory alternatives based on different conditions were generated using MOPSSAQMN. The compared results show that this study generated better alternatives than the current monitoring network. An installation schedule for the alternative was proposed, and its first step is now being implemented by the EPB of Taoyuan County Government. The procedure and computer system developed in this study can be used to assist the competent authorities to devise good and different alternatives for air quality monitoring networks planning.


Assuntos
Monitoramento Ambiental , Técnicas de Planejamento , Poluentes Atmosféricos/análise , Conservação dos Recursos Naturais , Custos e Análise de Custo , Poeira/análise , Órgãos Governamentais , Hidrocarbonetos/análise , Óxidos de Nitrogênio/análise , Software , Óxidos de Enxofre/análise , Análise de Sistemas , Taiwan
18.
Curr Drug Metab ; 17(7): 673-80, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27174458

RESUMO

BACKGROUND: In drug metabolism reactions, it has become increasingly important to measure Michaelis constants (Km), which are used for a variety of purposes, including identification of enzymes involved in drug metabolism, prediction of drug-drug interactions, etc. Cytochrome P450s (CYPs) comprise a super family of major human enzymes responsible for drug metabolism. Hence, computational prediction of Km in CYP-mediated reactions facilitates drug development in an efficient and economical way. METHODS: In this study, we firstly constructed a large dataset of ten CYP isoforms associated with 169 binding substrates, and 210 experimental Km values in CYP-mediated reactions. To predict Km of substrates metabolized by various CYP isoforms, we developed a general prediction model by using resilient back-propagation neutral network algorithm, based on the structural and physicochemical properties of the substrates and the metabolic specificity of the enzymes. RESULTS: The predictive Km values achieve a squared cross-validation correlation coefficients (Q2) of 0.73 with the experimental values, which is better than that of the existing models. Moreover, our model can predict Kmvalues of the compounds metabolized by a wide range of CYP isoforms. CONCLUSION: This tool will be useful in large-scale drug screening studies for CYP enzymes and helpful in the drug design and development.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Modelos Biológicos , Algoritmos , Interações Medicamentosas , Humanos , Preparações Farmacêuticas/metabolismo
19.
Sci Total Environ ; 346(1-3): 17-37, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15993679

RESUMO

Land use management is central to government planning for sustainable development. The main purpose of this study is to develop a novel strategy planning theory and system to assist responsible authorities in obtaining alternatives of sustainable top river basin land use management. The concepts and theory of system analysis, driving force-state-response (DSR) framework, and system dynamics are used to establish the DSR dynamic strategy planning procedure in this work. The integrated management of the land, water, and air resources of a river basin system is considered in the procedure. Two modified land use management procedures combined with the DSR dynamic strategy planning procedure are developed in this work. Based on the DSR dynamic strategy planning procedure, the sustainable river basin land use management DSR dynamic decision support system (SRBLUM-DSRD-DSS) is developed by using the Vensim, MS Excel, ArcView, and Visual Basic software. The concepts of object-orientation are used to develop the system dynamic optimization and simulation models of SRBLUM-DSRD-DSS. Based on the modified land use management procedures, SRBLUM-DSRD-DSS is used to assist decision makers in generating the land use plans of the Nankan river basin in Taoyuan County of Taiwan. Since the decisions of land, water and air resources management are still made at different agencies, the land use management system should be modified based on the innovational procedure to implement the management strategy developed in this work. The results show that the modified land use management procedures can be a guidance for the governments in modifying the systems and regulation of urban and regional plans in Taiwan.


Assuntos
Conservação dos Recursos Naturais , Meio Ambiente , Modelos Teóricos , Rios , Cidades , Formulação de Políticas , Taiwan , Abastecimento de Água
20.
Mol Cancer Ther ; 14(3): 810-20, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25589492

RESUMO

Blockade of EGFR has been proved useful in enhancing the effect of radiotherapy, but the advantages of new-generation EGFR tyrosine kinase inhibitors (TKI) in radiosensitization are not well known. We used two human bladder cancer cells with wild-type EGFR to study the synergism between irradiation and afatinib (an EGFR/HER2 dual kinase inhibitor) or erlotinib (an EGFR kinase inhibitor). Here, we showed that afatinib has better radiosensitizing effect than erlotinib in increasing cancer cell killing, the percentage of apoptotic cells, and DNA damage. Afatinib is also superior to erlotinib in combining radiation to decrease tumor size, inhibit glucose metabolism, and enhance apoptotic proteins in vivo. Finally, erlotinib suppressed cell growth and induced more DNA damage in bladder cancer cells transfected with HER2 shRNA, but not in control vector-treated cells. In conclusion, concomitant blockade of radiation-activated EGFR and HER2 signaling by a new-generation EGFR TKI better inhibits the growth of bladder cancer cells both in vitro and in vivo. The absence of radiosensitization by EGFR inhibition alone and the greater radiosensitizing effect of EGFR inhibitor in HER2 knocked down cells suggest the synergism between HER2 and EGFR in determining radiosensitivity. The regained radiosensitizing activity of erlotinib implies that with proper HER2 inhibition, EGFR tyrosine kinase is still a potential target to enhance radiotherapy effect in these seemingly unresponsive bladder cancer cells.


Assuntos
Receptores ErbB/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Radiossensibilizantes/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Neoplasias da Bexiga Urinária/tratamento farmacológico , Afatinib , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Cloridrato de Erlotinib/farmacologia , Humanos , Masculino , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinazolinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Bexiga Urinária/metabolismo
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