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1.
J Gastroenterol Hepatol ; 35(10): 1753-1760, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32365417

RESUMO

BACKGROUND AND AIMS: Segregated right intrahepatic duct dilatation (IHD) results from complete obstruction of the biliary tract proximal to the hilar level. We aimed to evaluate long-term efficacy and safety of endoscopic ultrasound (EUS) hepaticoduodenostomy (HDS) in segregated right IHD. METHODS: Consecutive patients who had undergone EUS-guided HDS with a fully covered self-expandable metal stent (FCSEMS) in an academic tertiary center were recruited. All patients had segregated right hepatic duct and failed drainage by endoscopic retrograde cholangiopancreatography (ERCP). Demographic data, endoscopic findings, procedure details, and outcome data were extracted from a prospectively maintained database. RESULTS: From 2013 to 2017, there were 35 patients who had undergone EUS-guided HDS with a median follow-up duration of 169 (3-2091) days. Malignancy accounted for 71.4% of the ductal segregation, followed by surgical complication (17.1%). Technical and clinical success rate was 97.1% and 80%, respectively. Early adverse event (AE) happened in seven patients (20%), two of them required endoscopic reintervention, and no percutaneous transhepatic biliary drainage (PTBD) or surgery was performed because of AE. The median stent patency duration was 331 (3-1202) days. The median duration of fistula tract keeping was 1280 (3-1280) days. There was no significant difference in terms of patency rate with respect to whether the underlying pathology was benign or malignant (P = 0.776). EUS-guided HDS for right posterior sectional duct segregation was associated with higher 3-month stent patency rate when compared with right anterior sectional duct (79.1% vs 38.1%, P = 0.012). CONCLUSION: Endoscopic ultrasound-guided HDS with an FCSEMS appears to be a safe and effective treatment as a viable alternative option to PTBD after failed ERCP. It creates a durable and reliable fistula tract for permanent access to an isolated ductal system, and this application deserves more attention.


Assuntos
Ductos Biliares Intra-Hepáticos/cirurgia , Procedimentos Cirúrgicos do Sistema Biliar/métodos , Duodenostomia/métodos , Endossonografia/métodos , Stents Metálicos Autoexpansíveis , Cirurgia Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Ductos Biliares Intra-Hepáticos/patologia , Dilatação Patológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
2.
Phytother Res ; 28(4): 617-22, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23873605

RESUMO

In this study, to evaluate the anti-obesity effects of fermented red ginseng (FG), levan (L), and their combination (FGL), we investigated their effects on the weights of body, liver and white adipose tissue, lipid profiles, and biomarkers for insulin resistance in high fat diet (HFD)-induced obese C57BL/6J male mice. Furthermore, the levels of leptin in the serum were measured. FG (150 mg/kg/d), L (100 mg/kg/d), and FGL (150 mg/kg/d of FG plus 100 mg/kg/d of L) were administered orally to mice daily for 11 weeks. After 11 weeks feeding, FGL showed significantly lower body weight and fat mass with decreasing food efficiency ratio than the HFD control mice. In addition, the FGL group was significantly lower in the levels of total cholesterol and fasting blood glucose and score of the homeostatic model assessment of insulin resistance. Furthermore, FGL decreased serum leptin levels compared to the HFD control group. Taken together, FGL showed a significant anti-obesity effect in HFD-induced obese mice and prevent insulin and leptin resistance. FGL may be potentially useful for the prevention of obesity.


Assuntos
Fármacos Antiobesidade/farmacologia , Frutanos/farmacologia , Obesidade/tratamento farmacológico , Panax/química , Tecido Adiposo Branco/efeitos dos fármacos , Animais , Glicemia/química , Peso Corporal , Colesterol/sangue , Dieta Hiperlipídica , Modelos Animais de Doenças , Fermentação , Hiperlipidemias/tratamento farmacológico , Insulina/sangue , Resistência à Insulina , Leptina/sangue , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/metabolismo , Extratos Vegetais/farmacologia
3.
Phytother Res ; 27(2): 166-72, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22511336

RESUMO

Ginseng has shown an efficacy in preventing and managing various health conditions. This study aimed to evaluate the effect of the fermented ginseng extract (FGE) in type 2 diabetes mellitus murine model. FGE was provided to male C57BL/ksJ-db/db mice for 8 weeks at 0.1% (w/w) dose in contrast to water for the control group. Potential anti-diabetic mechanisms were investigated with blood glucose, serum insulin, serum adiponectin, hemoglobin A1c (HbA1c), glucose tolerance, insulin secretion assay, quantitative real-time polymerase chain reaction, and hematoxylin-eosin staining. Compared with the control group, the FGE group had lower levels of blood glucose after 6 and 9 h fasting, HbA1c, and the area under the curve in an oral glucose tolerance test and higher levels of adiponectin and serum insulin (p < 0.05). The FGE group had higher levels of peroxisome proliferator-activated receptor gamma 2 and glucose transporter protein 2 mRNAs, a lower level of tumor necrosis factor-α (TNF-α) (p < 0.05), and less lymphocytes in pancreas than the control group had. The FGE exerted anti-diabetic effects in type 2 diabetic mice.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Panax/química , Extratos Vegetais/farmacologia , Adiponectina/sangue , Animais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Teste de Tolerância a Glucose , Transportador de Glucose Tipo 2/metabolismo , Hemoglobinas Glicadas/metabolismo , Homeostase , Insulina/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , PPAR gama/metabolismo
4.
Proc Inst Mech Eng H ; 226(4): 337-40, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22611874

RESUMO

We developed a novel concept of endovascular thrombolysis that employs a vibrating electroactive polymer actuator. In order to predict the efficacy of thrombolysis using the developed vibrating actuator, enzyme (plasminogen activator) perfusion into a clot was analyzed by solving flow fields and species transport equations considering the fluid structure interaction. In vitro thrombolysis experiments were also performed. Computational results showed that plasminogen activator perfusion into a clot was enhanced by actuator vibration at frequencies of 1 and 5 Hz. Plasminogen activator perfusion was affected by the actuator oscillation frequencies and amplitudes that were determined by electromechanical characteristics of a polymer actuator. Computed plasminogen activator perfused volumes were compared with experimentally measured dissolved clot volumes. The computed plasminogen activator perfusion volumes with threshold concentrations of 16% of the initial plasminogen activator concentration agreed well with the in vitro experimental data. This study showed the effectiveness of actuator oscillation on thrombolysis and the validity of the computational plasminogen activator perfusion model for predicting thrombolysis in complex flow fields induced by an oscillating actuator.


Assuntos
Coagulação Sanguínea/fisiologia , Catéteres , Trombólise Mecânica/instrumentação , Sistemas Microeletromecânicos/instrumentação , Modelos Cardiovasculares , Trombose/fisiopatologia , Trombose/terapia , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Vibração
5.
Clin Endosc ; 55(3): 452-457, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33657783

RESUMO

Colonic diffuse ganglioneuromatosis is an extremely rare disease in which multiple tumors derived from the ganglion cells, nerve fibers, and supporting cells are distributed in the colon. It is generally considered to be a benign neoplastic condition and is occasionally associated with rare hereditary conditions such as neurofibromatosis type I or multiple endocrine neoplasia type 2B. Here, we report a case of a patient in whom colon cancer developed 12 years after the initial diagnosis of colonic diffuse ganglioneuromatosis, which suggests a possible association between colonic diffuse ganglioneuromatosis and colorectal cancer.

7.
Diabetes ; 65(9): 2516-28, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27246913

RESUMO

Fibrosis of adipose tissue induces ectopic fat accumulation and insulin resistance by inhibiting adipose tissue expandability. Mechanisms responsible for the induction of adipose tissue fibrosis may provide therapeutic targets but are poorly understood. In this study, high-fat diet (HFD)-fed wild-type (WT) and iNOS(-/-) mice were used to examine the relationship between nitric oxide (NO) produced by macrophages and adipose tissue fibrosis. In contrast to WT mice, iNOS(-/-) mice fed an HFD were protected from infiltration of proinflammatory macrophages and adipose tissue fibrosis. Hypoxia-inducible factor 1α (HIF-1α) protein level was increased in adipose tissue of HFD-fed WT mice, but not iNOS(-/-) mice. In contrast, the expression of mitochondrial biogenesis factors was decreased in HFD-fed WT mice, but not iNOS(-/-) mice. In studies with cultured cells, macrophage-derived NO decreased the expression of mitochondrial biogenesis factors, and increased HIF-1α protein level, DNA damage, and phosphorylated p53 in preadipocytes. By activating p53 signaling, NO suppressed peroxisome proliferator-activated receptor γ coactivator 1α expression, which induced mitochondrial dysfunction and inhibited preadipocyte differentiation in adipocytes. The effects of NO were blocked by rosiglitazone. The findings suggest that NO produced by macrophages induces mitochondrial dysfunction in preadipocytes by activating p53 signaling, which in turn increases HIF-1α protein level and promotes a profibrogenic response in preadipocytes that results in adipose tissue fibrosis.


Assuntos
Adipócitos/citologia , Adipócitos/metabolismo , Fibrose/metabolismo , Macrófagos/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Nitritos/metabolismo , Adipócitos/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Fibrose/etiologia , Imunofluorescência , Teste de Tolerância a Glucose , Isotiurônio/análogos & derivados , Isotiurônio/farmacologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Células RAW 264.7
8.
Diabetes Metab J ; 39(5): 414-23, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26566499

RESUMO

BACKGROUND: The diagnosis of coronary artery disease (CAD) is often delayed in patients with type 2 diabetes. Serum total bilirubin levels are inversely associated with CAD. However, no studies have examined whether this can be used as a biochemical marker for identifying asymptomatic diabetic patients at higher risk for having obstructive CAD. METHODS: We performed a cross-sectional study of 460 consecutive asymptomatic patients with type 2 diabetes. All patients underwent coronary computed tomographic angiography, and their serum total bilirubin levels were measured. Obstructive CAD was defined as ≥50% diameter stenosis in at least one coronary artery. RESULTS: Serum total bilirubin tertiles showed an inverse association with the prevalence of obstructive CAD. In multivariate logistic regression analysis, the odds ratio for the highest versus the lowest tertile of total bilirubin was 0.227 (95% confidence interval [CI], 0.130 to 0.398), and an increment of 1 µmol/L in serum total bilirubin level was associated with a 14.6% decrease in obstructive CAD after adjustment for confounding variables. Receiver operating characteristic curve analysis showed that the area under the curve for the Framingham Risk Score (FRS) plus serum total bilirubin level was 0.712 (95% CI, 0.668 to 0.753), which is significantly greater than that of the FRS alone (P=0.0028). CONCLUSION: Serum total bilirubin level is inversely associated with obstructive CAD and provides additive risk information over the FRS. Serum total bilirubin may be helpful for identifying asymptomatic patients with type 2 diabetes who are at higher risk for obstructive CAD.

9.
Pharmacognosy Res ; 7(Suppl 1): S39-46, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26109786

RESUMO

BACKGROUND: Osteoarthritis (OA) is a chronic debilitating degenerative joint disease characterized by cartilage degradation and synovial inflammation exhibited by clinical symptoms such as joint swelling, synovitis, and inflammatory pain. Present day pain relief therapeutics heavily relies on the use of prescription and over the counter nonsteroidal anti-inflammatory drugs as the first line of defense where their long-term usage causes detrimental gastrointestinal and cardiovascular-related side-effects. As a result, the need for evidence based safer and efficacious alternatives from natural sources to overcome the most prominent and disabling symptoms of arthritis is a necessity. MATERIALS AND METHODS: Describe the anti-inflammatory and analgesic effect of UP3005, a composition that contains a standardized blend of two extracts from the leaf of Uncaria gambir and the root bark of Morus alba in carrageenan-induced rat paw edema, abdominal constriction (writhing's) and ear swelling assays in mouse with oral dose ranges of 100-400 mg/kg. RESULTS: In vivo, statistically significant improvement in pain resistance, and suppression of paw edema and ear thickness in animals treated with UP3005 were observed compared with vehicle-treated diseased rats and mice. Ibuprofen was used a reference compound in all the studies. In vitro, enzymatic inhibition activities of UP3005 were determined with IC50 values of 12.4 µg/ml, 39.8 µg/ml and 13.6 µg/ml in cyclooxygenase-2 (COX-1), COX-2 and lipoxygenase (5-LOX) enzyme activity assay, respectively. CONCLUSIONS: These data suggest that UP3005, analgesic and anti-inflammatory agent of botanical origin with balanced dual COX-LOX inhibition activity, could potentially be used for symptom management of OA.

10.
Artigo em Inglês | MEDLINE | ID: mdl-25802546

RESUMO

Osteoarthritis (OA) is a multifactorial disease primarily noted by cartilage degradation in association with inflammation that causes significant morbidity, joint pain, stiffness, and limited mobility. Present-day management of OA is inadequate due to the lack of principal therapies proven to be effective in hindering disease progression where symptomatic therapy focused approach masks the actual etiology leading to irreversible damage. Here, we describe the effect of UP3005, a composition containing a proprietary blend of two standardized extracts from the leaf of Uncaria gambir and the root bark of Morus alba, in maintaining joint structural integrity and alleviating OA associated symptoms in monosodium-iodoacetate- (MIA-) induced rat OA disease model. Pain sensitivity, micro-CT, histopathology, and glycosaminoglycans (GAGs) level analysis were conducted. Diclofenac at 10 mg/kg was used as a reference compound. UP3005 resulted in almost a complete inhibition in proteoglycans degradation, reductions of 16.6% (week 4), 40.5% (week 5), and 22.0% (week 6) in pain sensitivity, statistically significant improvements in articular cartilage matrix integrity, minimal visual subchondral bone damage, and statistically significant increase in bone mineral density when compared to the vehicle control with MIA. Therefore, UP3005 could potentially be considered as an alternative therapy from natural sources for the treatment of OA and/or its associated symptoms.

11.
J Endocrinol ; 225(3): 147-58, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25869616

RESUMO

Mitochondrial dysfunction in hypertrophic adipocytes can reduce adiponectin synthesis. We investigated whether 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) expression is increased in hypertrophic adipocytes and whether this is responsible for mitochondrial dysfunction and reduced adiponectin synthesis. Differentiated 3T3L1 adipocytes were cultured for up to 21 days. The effect of AZD6925, a selective 11ß-HSD1 inhibitor, on metabolism was examined. db/db mice were administered 600 mg/kg AZD6925 daily for 4 weeks via gastric lavage. Mitochondrial DNA (mtDNA) content, mRNA expression levels of 11 ß -H sd1 and mitochondrial biogenesis factors, adiponectin synthesis, fatty acid oxidation (FAO), oxygen consumption rate and glycolysis were measured. Adipocyte hypertrophy in 3T3L1 cells exposed to a long duration of culture was associated with increased 11 ß -Hsd1 mRNA expression and reduced mtDNA content, mitochondrial biogenesis factor expression and adiponectin synthesis. These cells displayed reduced mitochondrial respiration and increased glycolysis. Treatment of these cells with AZD6925 increased adiponectin synthesis and mitochondrial respiration. Inhibition of FAO by etomoxir blocked the AZD6925-induced increase in adiponectin synthesis, indicating that 11ß-HSD1-mediated reductions in FAO are responsible for the reduction in adiponectin synthesis. The expression level of 11 ß -Hsd1 was higher in adipose tissues of db/db mice. Administration of AZD6925 to db/db mice increased the plasma adiponectin level and adipose tissue FAO. In conclusion, increased 11ß-HSD1 expression contributes to reduced mitochondrial respiration and adiponectin synthesis in hypertrophic adipocytes.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Adiponectina/metabolismo , Tecido Adiposo Branco/metabolismo , Metabolismo Energético , Regulação da Expressão Gênica , Obesidade/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , Células 3T3-L1 , Adamantano/análogos & derivados , Adamantano/uso terapêutico , Adiponectina/sangue , Adiponectina/genética , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/patologia , Animais , Metabolismo Energético/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Hipertrofia , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipotrópicos/farmacologia , Lipotrópicos/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Mutantes , Dinâmica Mitocondrial , Niacinamida/análogos & derivados , Niacinamida/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Obesidade/tratamento farmacológico , Obesidade/patologia , Obesidade/fisiopatologia , Consumo de Oxigênio/efeitos dos fármacos
12.
Comput Biol Med ; 44: 37-43, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24377687

RESUMO

Drug delivery into neurological tissue is challenging because of the low tissue permeability. Ultrasound incorporating microbubbles has been applied to enhance drug delivery into these tissues, but the effects of a streaming flow by microbubble oscillation on drug perfusion have not been elucidated. In order to clarify the physical effects of steady streaming on drug delivery, an experimental study on dye perfusion into a tissue model was performed using microbubbles excited by acoustic waves. The surface concentration and penetration length of the drug were increased by 12% and 13%, respectively, with streaming flow. The mass of dye perfused into a tissue phantom for 30s was increased by about 20% in the phantom with oscillating bubbles. A computational model that considers fluid structure interaction for streaming flow fields induced by oscillating bubbles was developed, and mass transfer of the drug into the porous tissue model was analyzed. The computed flow fields agreed with the theoretical solutions, and the dye concentration distribution in the tissue agreed well with the experimental data. The computational results showed that steady streaming with a streaming velocity of a few millimeters per second promotes mass transfer into a tissue.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Microbolhas , Modelos Teóricos , Tecido Nervoso , Ultrassom , Humanos , Permeabilidade
13.
ASAIO J ; 58(5): 503-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22820916

RESUMO

In this study, we propose a new method for the enhancement of intraarterial thrombolysis by use of an endovascular vibrating polymer actuator probe (VPAP), which is fabricated from an ionic polymer metal composite (IPMC) actuator. The endovascular VPAP was fabricated by combining 0.8 × 0.8 × 10 mm3 IPMC samples, 0.22 mm × 50 cm copper wires, and 40 cm of Teflon tube. The purpose of this study was to evaluate the thrombolysis efficiency of an endovascular VPAP in a dog model. Both renal arteries of the enrolled dogs (n = 5) were used in the current study. A distal portion of the renal artery in a mongrel dog was occluded by a blood clot from autologous venous whole blood. Intraarterial thrombolysis was performed by use of a VPAP without the actuation force (control group), by a VPAP-only (VPAP-only group), or with a combination of recombinant tissue plasminogen activator (rtPA) and a VPAP (VPAP + rtPA group). The thrombolysis efficiency was evaluated by the modified Thrombolysis in Myocardial Infarction (TIMI) grading system based on the consensus between two radiologists. The grading scales were compared according to each intraarterial thrombolysis method. The VPAP + rtPA and VPAP-only groups showed a significantly higher thrombolysis efficiency than did the control group (p < 0.05). The VPAP-only group also showed a significantly higher thrombolysis efficiency than did the control group (p < 0.05). The VPAP+ rtPA group showed a significantly higher thrombolysis efficiency than did the VPAP-only group (p < 0.05). The use of an endovascular VPAP was a feasible and useful method for intraarterial thrombolysis, and it enhanced the thrombolysis efficiency when combined with the thrombolytic agent rtPA.


Assuntos
Trombólise Mecânica/instrumentação , Animais , Materiais Biocompatíveis , Cães , Desenho de Equipamento , Trombólise Mecânica/métodos , Modelos Animais , Modelos Cardiovasculares , Polímeros , Artéria Renal/lesões , Obstrução da Artéria Renal/terapia , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/uso terapêutico , Vibração
14.
Neurointervention ; 6(1): 13-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22125742

RESUMO

PURPOSE: Computational flow dynamic (CFD) study has not been widely applied in intracranial artery stenosis due to requirement of high resolution in identifying the small intracranial artery. We described a process in CFD study applied to symptomatic severe intracranial (M1) stenosis before and after stenting. MATERIALS AND METHODS: Reconstructed 3D angiography in STL format was transferred to Magics (Materialise NV, Leuven, Belgium) for smoothing of vessel surface and trimming of branch vessels and to HyperMesh (Altair Engineering Inc., Auckland, New Zealand) for generating tetra volume mesh from triangular surface-meshed 3D angiogram. Computational analysis of blood flow in the blood vessels was performed using the commercial finite element software ADINA Ver 8.5 (ADINA R & D, Inc., Lebanon, MA). The distribution of wall shear stress (WSS), peak velocity and pressure in a patient was analyzed before and after intracranial stenting. RESULTS: Computer simulation of wall shear stress, flow velocity and wall pressure before and after stenting could be demonstrated three dimensionally by video mode according to flow vs. time dimension. Such flow model was well correlated with angiographic finding related to maximum degree of stenosis. Change of WSS, peak velocity and pressure at the severe stenosis was demonstrated before and after stenting. There was no WSS after stenting in case without residual stenosis. CONCLUSION: Our study revealed that CFD analysis before and after intracranial stenting was feasible despite of limited vessel wall dimension and could reveal change of WSS as well as flow velocity and wall pressure.

15.
ASAIO J ; 57(4): 286-92, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21701271

RESUMO

In this study, we propose a new method for enhancement of intraarterial thrombolysis using an ionic polymer-metal composite (IPMC) actuator. The purpose of this study was to test the mechanical thrombolysis efficiency of IPMC actuators and evaluate the endovascular vibrating polymer actuator probe for mechanical thrombolysis in a phantom model; 2 × 1 × 15 mm (2 mm in width, 1 mm in thickness, and 15 mm in length) and 0.8 × 0.8 × 10 mm (0.8 mm in width, 0.8 mm in thickness, and 10 mm in length) IPMC actuators were fabricated by stacking five and four Nafion-117 films, respectively. We manufactured the endovascular vibrating polymer actuator probe, for which thrombolysis efficiency was tested in a vascular phantom. The phantom study using 2 × 1 × 15 mm IPMC actuators showed that 5 Hz actuation is the optimal frequency for thrombolysis under both 2 and 3 V, when blood clot was not treated with rtPA, and when exposed to rtPA, IPMC actuators under the optimized condition (3 V, 5 Hz, and 5 min) significantly increased the thrombolysis degree compared with control and other experimental groups (p < 0.05). In addition, 0.8 × 0.8 × 10 mm IPMC actuators also revealed a significantly higher thrombolysis degree under the optimized condition than the control and rtPA only groups (p < 0.05). Finally, the fabricated probe using 0.8 × 0.8 × 10 mm IPMC actuators also incurred higher thrombolysis degree under the optimized condition than the control and rtPA only groups (p < 0.05). A vibrating polymer actuator probe is a feasible device for intravascular thrombolysis, and further study in an animal model is warranted.


Assuntos
Íons/química , Metais/química , Polímeros/química , Terapia Trombolítica/métodos , Coagulação Sanguínea , Fístula/patologia , Hemólise , Humanos , Teste de Materiais , Imagens de Fantasmas , Reprodutibilidade dos Testes , Fatores de Tempo , Vibração
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