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1.
Mol Ther ; 27(9): 1681-1693, 2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-31326400

RESUMO

The molecular mechanism of hemodialysis access arteriovenous fistula (AVF) failure due to venous neointimal hyperplasia (VNH) is not known. The role of microRNA-21 (miR-21) in VNH associated with AVF failure was investigated by performing in vivo and in vitro experiments. In situ hybridization results revealed that miR-21 expression increased and was associated with fibroblasts in failed AVFs from patients. In a murine AVF model, qRT-PCR gene expression results showed a significant increase in miR-21 and a decrease in miR-21 target genes in graft veins (GVs) compared to contralateral veins in mouse AVF. miR-21 knockdown in GVs was performed using a lentivirus-mediated small hairpin RNA (shRNA), and this improved AVF patency with a decrease in neointima compared to control GVs. Moreover, loss of miR-21 in GVs significantly decreased the Tgfß1, Col-Ia, and Col-Iva genes. Immunohistochemistry demonstrated a significant decrease in myofibroblasts and proliferation with an increase in terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining in miR-21-knockdown vessels, along with a decrease in hypoxia-inducible factor-1 alpha (HIF-1α) and phospho-SMAD2 (pSMAD-2) and phospho-SMAD3 (pSMAD-3) and an increase in phosphatase and tensin homolog (PTEN) staining. Hypoxic fibroblast knockdown for miR-21 showed a significant decrease in Tgfß-1 expression and pSMAD-2 and -3 levels and a decrease in myofibroblasts. These results indicate that miR-21 upregulation causes VNH formation by fibroblast-to-myofibroblast differentiation.


Assuntos
MicroRNAs/genética , Neointima/genética , Neointima/patologia , Veias/metabolismo , Veias/patologia , Animais , Apoptose/genética , Fístula Arteriovenosa/genética , Fístula Arteriovenosa/patologia , Biomarcadores , Diferenciação Celular/genética , Proliferação de Células , Modelos Animais de Doenças , Fibroblastos/metabolismo , Fibrose/genética , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Hiperplasia , Hipóxia/genética , Hipóxia/metabolismo , Imuno-Histoquímica , Lentivirus/genética , Masculino , Camundongos , Miofibroblastos/metabolismo , Neointima/terapia , Interferência de RNA , RNA Interferente Pequeno/genética , Transdução Genética
2.
Polymers (Basel) ; 11(3)2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30960407

RESUMO

There is a need to develop a chemiresistive gas sensor equipped with a thermostat over a wide area for the sensor, which can protect the sensor from the influence of ambient temperature due to the uniform temperature of the thermostat. In this paper, we demonstrated an acetone gas sensor based on a polyethylene glycol (PEG)/Multi-walled Carbon Nanotubes (MWCNTs) composite film, which was equipped with a thermostat. The sensor was operated at modest working temperatures for sensor sensitivity enhancement. The optimum design of the polyimide-based thermostat with widely uniform thermal distribution was investigated in detail. It was found that the temperature uniformity of the thermostat was achieved using double spiral geometry. The experimental results of the sensor response showed that the PEG/MWCNTs composite film with a moderate working temperature revealed a higher sensitivity than that without thermal treatment. Moreover, the sensing mechanisms of the PEG/MWCNTs composite gas sensor to acetone vapor were studied as well.

3.
Polymers (Basel) ; 9(9)2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-30965760

RESUMO

In this study, an integrated flexible gas sensor was developed based on a polymer/multi-walled carbon nanotube composite film by using Bluetooth wireless communication/interface technology. Polymer/multi-walled carbon nanotube composite films were deposited over a polyimide flexible substrate for building a gas sensor array by using a drop-casting method. Sensor response was acquired through interdigitated electrodes and multi-channel sensor boards, which were linked to a Bluetooth wireless transceiver. Additionally, a double-spiral-shaped heater was built into the backside of the gas sensor array as a thermostat to protect it from the influence of ambient temperature. Multi-channel sensing responses were read on a display screen via a smartphone application (app). The advantages of this system include light weight, low cost, highly integrated sensors, wireless telecommunication, and real-time functioning. Thus, it is a promising candidate for deployment in a wearable gas-sensing system used to study air pollution.

4.
Sensors (Basel) ; 17(1)2016 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-28025507

RESUMO

This study examined the performance of a flexible polymer/multi-walled carbon nanotube (MWCNT) composite sensor array as a function of operating temperature. The response magnitudes of a cost-effective flexible gas sensor array equipped with a heater were measured with respect to five different operating temperatures (room temperature, 40 °C, 50 °C, 60 °C, and 70 °C) via impedance spectrum measurement and sensing response experiments. The selected polymers that were droplet cast to coat a MWCNT conductive layer to form two-layer polymer/MWCNT composite sensing films included ethyl cellulose (EC), polyethylene oxide (PEO), and polyvinylpyrrolidone (PVP). Electrical characterization of impedance, sensing response magnitude, and scanning electron microscope (SEM) morphology of each type of polymer/MWCNT composite film was performed at different operating temperatures. With respect to ethanol, the response magnitude of the sensor decreased with increasing operating temperatures. The results indicated that the higher operating temperature could reduce the response and influence the sensitivity of the polymer/MWCNT gas sensor array. The morphology of polymer/MWCNT composite films revealed that there were changes in the porous film after volatile organic compound (VOC) testing.

5.
Kaohsiung J Med Sci ; 22(1): 1-13, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16570562

RESUMO

The epidemiology of Taenia saginata in some parts of Asia is confusing, in that beef does not appear to be the source of infection. In some areas, beef is either not available or not eaten raw, whereas pork at times is eaten uncooked. In light of this situation, we have exposed pigs and other animals to infection with strains of T. saginata to establish their ability to serve as intermediate hosts. Eggs of Taiwan Taenia, Korea Taenia, Indonesia Taenia, Thailand Taenia, Philippines Taenia, Ethiopia Taenia, and Madagascar Taenia were fed to 83 pigs of three strains: 43 Small-Ear Miniature (SEM), 34 Landrace Small-Ear Miniature (L-SEM), and 6 Duroc-Yorkshire-Landrace (DYL). We also fed the eggs to 10 Holstein calves, 17 Sannean goats, and 4 monkeys (Macaca cyclopis). We succeeded in infecting SEM (infection rate 88%, cysticercus recovery rate 19.1%), L-SEM (83%, 1.1%), and DYL (100%, 0.3%) pigs with Taiwan Taenia; SEM (100%, 1.7%), L-SEM (100%, 5.6%), and DYL (100%, 0.06%) pigs with Korea Taenia; SEM (100%, 22%) and L-SEM (100%, 1.6%) pigs with Indonesia Taenia; SEM (75%, 0.06%) pigs with Thailand Taenia SEM (100%, 11%) pigs with Philippines Taenia; SEM (80%, 0.005%) pigs with Ethiopia Taenia; SEM (100%, 0.2%) pigs with Madagascar Taenia. Holstein calves became infected with Taenia from Taiwan (100%, 1.1%), Korea (100%, 0.03%), Thailand (100%, 0.2%), and the Philippines (100%, 6%); however, the cysticerci of Taenia from Korea, Thailand, and the Philippines were degenerated and/or calcified. Sannean goats became infected with Taenia from Taiwan (33%, 0.01%) and Korea (50%, 0.02%), while monkeys became infected with Taenia from Taiwan (50%, 0.01%). However, the cysticerci were degenerated and/ or calcified. Therefore, these strains of pig seem to be favorable animal models for experimental studies of T. saginata-like tapeworms, with the SEM pig the most favorable.


Assuntos
Suínos/parasitologia , Taenia saginata , Teníase/transmissão , Animais , Modelos Animais de Doenças , Reservatórios de Doenças , Suscetibilidade a Doenças , Humanos , Fígado/parasitologia , Taenia saginata/classificação
6.
Kaohsiung J Med Sci ; 21(10): 448-51, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16302447

RESUMO

In order to determine the minimum effective dosages of praziquantel, albendazole, and mebendazole against Clonorchis sinensis infection in Sprague-Dawley rats, each rat was infected with 30 metacercariae and treated with one of three drugs. The rats were killed and examined 25 days after praziquantel treatment or 11 days after albendazole or mebendazole treatment. The minimum effective dosages were a single dose of praziquantel 375 mg/kg, albendazole 150 mg/kg, and mebendazole 150 mg/kg. Trials are required to determine whether these dosages are useful in the treatment of human clonorchiasis.


Assuntos
Anti-Helmínticos/administração & dosagem , Clonorquíase/tratamento farmacológico , Clonorchis sinensis/efeitos dos fármacos , Albendazol/administração & dosagem , Albendazol/uso terapêutico , Animais , Anti-Helmínticos/uso terapêutico , Clonorquíase/parasitologia , Relação Dose-Resposta a Droga , Masculino , Mebendazol/administração & dosagem , Mebendazol/uso terapêutico , Praziquantel/administração & dosagem , Praziquantel/uso terapêutico , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
7.
J Formos Med Assoc ; 103(12): 914-20, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15624040

RESUMO

BACKGROUND AND PURPOSE: Statins may have anti-inflammatory properties and exert endothelial protection independently of their lipid-lowering effect. However, data are scarce concerning the co-existence of these lipid-lowering-independent effects in humans. METHODS: Forty three patients with hypercholesterolemia were randomly assigned in a 2:1 ratio to receive either fluvastatin 80 mg/day (n = 30) or placebo (n = 13) for 12 weeks. Plasma levels of monocyte chemotactic protein-1 (MCP-1), thiobarbituric acid reactive substances (TBARS)--an index of oxidative stress, and flow-mediated vasodilatation (FMD)--an index of endothelial function, were measured before and after statin therapy. RESULTS: Fluvastatin significantly reduced the serum level of total cholesterol (201.8 +/- 25.2 vs 271.6 +/- 24.7 mg/dL; p < 0.001), low-density lipoprotein cholesterol (129.4 +/- 5.1 vs 190.2 +/- 19 mg/dL; p < 0.001), MCP-1 (190.3 +/- 40 vs 217.6 +/- 61 pg/mL; p = 0.001), and TBARS (3.7 +/- 1.3 vs 5.2 +/- 1.4 nmol/mL; p < 0.001). FMD was significantly increased, from 3.7 +/- 2.5% to 5.9 +/- 2.9% (p < 0.001) in the fluvastatin group. The reduction of serum MCP-1 or TBARS level was not correlated with the improvement of either plasma cholesterol level or FMD. No significant changes of these markers were observed in the placebo group. CONCLUSIONS: Fluvastatin reduced oxidative stress and inflammatory marker levels, and improved endothelial function, in addition to its lipid-lowering effect. These observations provide a clinical rationale for the co-existence of complex and multiple vascular protective mechanisms of statins.


Assuntos
Quimiocina CCL2/sangue , Endotélio Vascular/efeitos dos fármacos , Ácidos Graxos Monoinsaturados/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Indóis/uso terapêutico , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Idoso , Biomarcadores/sangue , Método Duplo-Cego , Feminino , Fluvastatina , Humanos , Hipercolesterolemia/sangue , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
8.
J Microbiol Immunol Infect ; 36(2): 96-100, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12886959

RESUMO

In this study, 12 Small-Ear-Miniature pigs aged 142 to 185 days were used to determine whether pigs injected with nonviable oncospheres of Taenia solium or Taenia saginata asiatica can become resistant to the challenge of viable eggs of T. solium. The 12 pigs were equally divided into 4 groups: 3 experimental groups in which each pig was injected subcutaneously with a mixture of 0.2 mL complete Freund's adjuvant and 10(4)/0.2 mL nonviable Taiwan/Asian Taenia, Indonesia Taenia, or T. solium oncospheres, and 1 control group in which each pig was injected subcutaneously with 0.2 mL phosphate buffer solution and 0.2 mL complete Freund's adjuvant. Each pig was orally inoculated with 10000 viable T. solium eggs 1 month later. The infection rates were 100% (2/2), 100% (3/3), 33% (1/3), and 100% (3/3) and cysticerci recovery rates were 1.3% (254/20000), 1.2% (371/30000), 0.01% (4/30000), and 8.6% (2,577/30000), respectively. Except for the location of 72 cysticerci located in the viscera, 3134 cysticerci were recovered from the muscles. In the experimental groups, 4 cysticerci recovered were viable and the remaining 625 were either calcified or degenerated. However, 2567 cysticerci recovered from the control group remained viable and only 10 were calcified or degenerated. The results indicate that in addition to the vaccine of T. solium, those of Taiwan Taenia and Indonesia Taenia can also induce high-crossing immunologic reactions against T. solium infection.


Assuntos
Doenças dos Suínos/prevenção & controle , Taenia solium/imunologia , Teníase/veterinária , Vacinação/veterinária , Animais , Congelamento , Humanos , Óvulo/imunologia , Suínos , Taenia saginata , Teníase/prevenção & controle
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