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1.
J Org Chem ; 84(13): 8702-8709, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31244162

RESUMO

Inorganic persulfate salts were identified as efficient reagents for the oxidative aromatization of 3,4-dihydroquinolin-2(1 H)-ones through the activation of readily available transition metals, such as iron and copper. The feasible protocol conforming to the requirement of green chemistry was utilized in the preparation of the key intermediate (7-(4-chlorobutoxy)quinolin-2(1 H)-one 2) of brexpiprazole in 80% isolated yield on a 100 g scale, and different quinolin-2(1 H)-one derivatives with various functional groups were demonstrated in 52-89% yields.

2.
Neurosci Lett ; 826: 137723, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38467272

RESUMO

Cannabidiol (CBD), a non-psychoactive compound derived from the cannabis plant, has been confirmed to induce anxiolytic-like and antipsychotic-like effects. However, the exact mechanisms remain unclear. This study substantiated CBD's interaction with the 5-HT1A receptor (5-HT1AR) in vitro (CHO cells expressing human 5-HT1AR) and in vivo (rat lower lip retraction test, LLR test). We then assessed the impact of CBD in mice using the stress-induced hyperthermia (SIH) model and the phencyclidine (PCP)-induced negative symptoms of schizophrenia model, respectively. Concurrently, we investigated whether WAY-100635, a typical 5-HT1AR antagonist, could attenuate these effects. Furthermore, the neurotransmitter changes through high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) were studied. Results revealed that CBD exhibits selective 5-HT1AR agonists-mediated effects in the rat lower lip retraction test, aligning with the robust agonistic (EC50 = 1.75 µM) profile observed in CHO cells. CBD at 3 mg/kg significantly reduced SIH (ΔT), a response that WAY-100635 abolished. Chronic administration of CBD at 100 mg/kg mitigated the increase in PCP-induced immobility time in the forced swim test (FST) and tail suspension test (TST). Moreover, it induced significant alterations in gamma-aminobutyric acid (GABA) and norepinephrine (NE) levels within the hippocampus (HPC). Thus, we concluded that the 5-HT1AR mediates CBD's anxiolytic-like effects. Additionally, CBD's effects on the negative symptoms of schizophrenia may be linked to changes in GABA and NE levels in the hippocampus. These findings offer novel insights for advancing the exploration of CBD's anxiolytic-like and antipsychotic-like effects.


Assuntos
Ansiolíticos , Antipsicóticos , Canabidiol , Cricetinae , Camundongos , Ratos , Humanos , Animais , Antipsicóticos/farmacologia , Ansiolíticos/farmacologia , Canabidiol/farmacologia , Serotonina , Cricetulus , Cromatografia Líquida , Espectrometria de Massas em Tandem , Ácido gama-Aminobutírico
3.
Eur J Med Chem ; 265: 116048, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38150961

RESUMO

Cannabinoid CB2R agonists have gained considerable attention as potential novel therapies for psychiatric disorders due to their non-psychoactive nature, in contrast to CB1R agonists. In this study, we employed molecular docking to design and synthesize 23 derivatives of cannabidiol (CBD) with the aim of discovering potent CB2R agonists rather than CB2R antagonists or inverse agonists. Structure-activity relationship (SAR) investigations highlighted the critical importance of the amide group at the C-3' site and the cycloalkyl group at the C-4' site for CB2R activation. Interestingly, three CBD derivatives, namely 2o, 6g, and 6h, exhibited substantial partial agonistic activity towards the CB2 receptor, in contrast to the inverse agonistic property of CBD. Among these, 2o acted as a CB2R and 5-HT1AR dual agonist, albeit with some undesired antagonist activity for CB1R. It demonstrated significant CB2R partial agonism while maintaining a level of 5-HT1AR agonistic and CB1R antagonistic activity similar to CBD. Pharmacokinetic experiments confirmed that 2o possesses favorable pharmacokinetic properties. Behavioral studies further revealed that 2o elicits significant antidepressant-like and anxiolytic-like effects while maintaining a good safety profile.


Assuntos
Canabidiol , Receptor 5-HT1A de Serotonina , Humanos , Simulação de Acoplamento Molecular , Serotonina , Depressão/tratamento farmacológico , Agonismo Inverso de Drogas , Agonistas de Receptores de Canabinoides , Canabidiol/farmacologia , Canabidiol/uso terapêutico , Agonistas do Receptor de Serotonina , Ansiedade , Receptor CB2 de Canabinoide , Receptor CB1 de Canabinoide
4.
Small ; 9(23): 4017-26, 2013 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-23766267

RESUMO

Cell therapies offer exciting new opportunities for effectively treating many human diseases. However, delivery of therapeutic cells by intravenous injection, while convenient, relies on the relatively inefficient process of homing of cells to sites of injury. To address this limitation, a novel strategy has been developed to load cells with superparamagnetic iron oxide nanoparticles (SPIOs), and to attract them to specific sites within the body by applying an external magnetic field. The feasibility of this approach is demonstrated using human mesenchymal stem cells (hMSCs), which may have a significant potential for regenerative cell therapies due to their ease of isolation from autologous tissues, and their ability to differentiate into various lineages and modulate their paracrine activity in response to the microenvironment. The efficient loading of hMSCs with polyethylene glycol-coated SPIOs is achieved, and it is found that SPIOs are localized primarily in secondary lysosomes of hMSCs and are not toxic to the cells. Further, the key stem cell characteristics, including the immunophenotype of hMSCs and their ability to differentiate, are not altered by SPIO loading. Through both experimentation and mathematical modeling, it is shown that, under applied magnetic field gradients, SPIO-containing cells can be localized both in vitro and in vivo. The results suggest that, by loading SPIOs into hMSCs and applying appropriate magnetic field gradients, it is possible to target hMSCs to particular vascular networks.


Assuntos
Compostos Férricos/química , Nanopartículas de Magnetita/química , Células-Tronco Mesenquimais/citologia , Nanopartículas/química , Humanos , Nanopartículas de Magnetita/efeitos adversos , Nanopartículas/efeitos adversos
5.
J Agric Food Chem ; 71(50): 20359-20371, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38059915

RESUMO

The regulation of fatty acid metabolism is crucial for milk flavor and quality. Therefore, it is important to explore the genes that play a role in fatty acid metabolism and their mechanisms of action. The RNA-binding protein Musashi2 (MSI2) is involved in the regulation of numerous biological processes and plays a regulatory role in post-transcriptional translation. However, its role in the mammary glands of dairy cows has not been reported. The present study examined MSI2 expression in mammary glands from lactating and dry milk cows. Experimental results in bovine mammary epithelial cells (BMECs) showed that MSI2 was negatively correlated with the ability to synthesize milk fat and that MSI2 decreased the content of unsaturated fatty acids (UFAs) in BMECs. Silencing of Msi2 increased triglyceride accumulation in BMECs and increased the proportion of UFAs. MSI2 affects TAG synthesis and milk fat synthesis by regulating fatty acid synthase (FASN). In addition, RNA immunoprecipitation experiments in BMECs demonstrated for the first time that MSI2 can bind to the 3'-UTR of FASN mRNA to exert a regulatory effect. In conclusion, MSI2 affects milk fat synthesis and fatty acid metabolism by regulating the triglyceride synthesis and UFA content through binding FASN.


Assuntos
Ácidos Graxos , Lactação , Feminino , Bovinos , Animais , Ácidos Graxos/metabolismo , Glândulas Mamárias Animais/metabolismo , Ácidos Graxos Insaturados/metabolismo , Leite/química , Triglicerídeos/metabolismo , Ácido Graxo Sintases/genética , Células Epiteliais/metabolismo
6.
Circulation ; 124(7): 779-88, 2011 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-21788584

RESUMO

BACKGROUND: Experimental studies suggest that low wall shear stress (WSS) promotes plaque development and high WSS is associated with plaque destabilization. We hypothesized that low-WSS segments in patients with coronary artery disease develop plaque progression and high-WSS segments develop necrotic core progression with fibrous tissue regression. METHODS AND RESULTS: Twenty patients with coronary artery disease underwent baseline and 6-month radiofrequency intravascular ultrasound (virtual histology intravascular ultrasound) and computational fluid dynamics modeling for WSS calculation. For each virtual histology intravascular ultrasound segment (n=2249), changes in plaque area, virtual histology intravascular ultrasound-derived plaque composition, and remodeling were compared in low-, intermediate-, and high-WSS categories. Compared with intermediate-WSS segments, low-WSS segments developed progression of plaque area (P=0.027) and necrotic core (P<0.001), whereas high-WSS segments had progression of necrotic core (P<0.001) and dense calcium (P<0.001) and regression of fibrous (P<0.001) and fibrofatty (P<0.001) tissue. Compared with intermediate-WSS segments, low-WSS segments demonstrated greater reduction in vessel (P<0.001) and lumen area (P<0.001), and high-WSS segments demonstrated an increase in vessel (P<0.001) and lumen (P<0.001) area. These changes resulted in a trend toward more constrictive remodeling in low- compared with high-WSS segments (73% versus 30%; P=0.06) and more excessive expansive remodeling in high- compared with low-WSS segments (42% versus 15%; P=0.16). CONCLUSIONS: Compared with intermediate-WSS coronary segments, low-WSS segments develop greater plaque and necrotic core progression and constrictive remodeling, and high-WSS segments develop greater necrotic core and calcium progression, regression of fibrous and fibrofatty tissue, and excessive expansive remodeling, suggestive of transformation to a more vulnerable phenotype. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00576576.


Assuntos
Doença da Artéria Coronariana , Vasos Coronários , Placa Aterosclerótica , Ultrassonografia de Intervenção/métodos , Idoso , Calcinose/diagnóstico por imagem , Calcinose/patologia , Calcinose/fisiopatologia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Vasos Coronários/fisiopatologia , Progressão da Doença , Feminino , Fibrose , Humanos , Hidrodinâmica , Masculino , Pessoa de Meia-Idade , Necrose , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/patologia , Placa Aterosclerótica/fisiopatologia , Estudos Prospectivos , Estresse Mecânico
7.
Am Heart J ; 161(3): 508-15, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21392605

RESUMO

BACKGROUND: Although culprit lesions in ST-segment elevation myocardial infarction (STEMI) cluster in the proximal coronary arteries, their relationship to bifurcations and curvatures, where blood flow is disturbed, is unknown. We hypothesized that (a) culprit lesions localize to disturbed flow distal to bifurcations and curvatures and (b) the distribution of culprit lesions in the left (LCA) and right coronary arteries (RCA) and resulting infarct size are related to the location of bifurcations and curvatures. METHODS: Emory University's contribution to the National Cardiovascular Data Registry was queried for STEMIs. Using quantitative coronary angiography, the distances from the vessel ostium, major bifurcations, and major curvatures to the culprit lesion were measured in 385 patients. RESULTS: Culprit lesions were located within 20 mm of a bifurcation in 79% of patients and closer to the bifurcation in the LCA compared with the RCA (7.4 ± 7.3 vs 17.7 ± 14.8 mm, P < .0001). Of RCA culprit lesions, 45% were located within 20 mm of a major curvature. Compared with those in the RCA, culprit lesions in the LCA were located more proximally (24.4 ± 16.5 vs 44.7 ± 28.8 mm, P = .0003) and were associated with larger myocardial infarctions as assessed by peak creatine kinase-MB (208 ± 222 vs 140 ± 153 ng/dL, P = .001) and troponin I (59 ± 62 vs 40 ± 35 ng/dL, P = .0006) and with higher in-hospital mortality (5.2% vs 1.1%, P = .04). CONCLUSIONS: In patients with STEMI, culprit lesions are frequently located immediately distal to bifurcations and in proximity to major curvatures where disturbed flow is known to occur. This supports the role of wall shear stress in the pathogenesis of STEMI.


Assuntos
Vasos Coronários/patologia , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/patologia , Placa Aterosclerótica/patologia , Síndrome Coronariana Aguda/patologia , Idoso , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Placa Aterosclerótica/fisiopatologia , Fluxo Sanguíneo Regional
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(5): 1423-7, 2011 May.
Artigo em Zh | MEDLINE | ID: mdl-21800614

RESUMO

Ore sample, pretreated at 650 degrees C, was decomposed with aqua regia. Gold in the sample solution was then pre-concentrated by adsorbing with polyurethane foam plastic, released with thiourea solution, and determined by inductively coupled plasma-atomic emission spectrometry and flame atomic absorption spectrometry. Based on the characteristic of the copper matte and sinter containing copper, the effects of sample dissolving condition, matrix effect and interference of coexisting elements were investigated. The accuracy, precision and detection limit were discussed. The results of test show that both of the two methods were suitable for determining the contents of gold in copper matte and sintered copper material.

9.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): o2837, 2010 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-21589023

RESUMO

In the title mol-ecule, C(17)H(18)O(5), which was prepared by the reaction of (R)-1,5-dioxaspiro-[5.5]undecane-2,4-dione and 4-meth-oxy-benzaldehyde with ethanol, the 1,3-dioxane ring is in a distorted envelope conformation with the spiro C atom forming the flap. The crystal structure is stabilized by weak inter-molecular C-H⋯O hydrogen bonds.

10.
Am J Physiol Heart Circ Physiol ; 297(4): H1535-43, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19684185

RESUMO

Atherosclerosis is closely associated with disturbed flow characterized by low and oscillatory shear stress, but studies directly linking disturbed flow to atherogenesis is lacking. The major reason for this has been a lack of an animal model in which disturbed flow can be acutely induced and cause atherosclerosis. Here, we characterize partial carotid ligation as a model of disturbed flow with characteristics of low and oscillatory wall shear stress. We also describe a method of isolating intimal RNA in sufficient quantity from mouse carotid arteries. Using this model and method, we found that partial ligation causes upregulation of proatherogenic genes, downregulation of antiatherogenic genes, endothelial dysfunction, and rapid atherosclerosis in 2 wk in a p47(phox)-dependent manner and advanced lesions by 4 wk. We found that partial ligation results in endothelial dysfunction, rapid atherosclerosis, and advanced lesion development in a physiologically relevant model of disturbed flow. It also allows for easy and rapid intimal RNA isolation. This novel model and method could be used for genome-wide studies to determine molecular mechanisms underlying flow-dependent regulation of vascular biology and diseases.


Assuntos
Artérias Carótidas/fisiopatologia , Doenças das Artérias Carótidas/fisiopatologia , Modelos Animais de Doenças , Endotélio Vascular/fisiopatologia , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/metabolismo , Artérias Carótidas/patologia , Artérias Carótidas/cirurgia , Doenças das Artérias Carótidas/etiologia , Doenças das Artérias Carótidas/genética , Doenças das Artérias Carótidas/patologia , Simulação por Computador , Gorduras na Dieta/administração & dosagem , Progressão da Doença , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Feminino , Regulação da Expressão Gênica , Ligadura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Cardiovasculares , NADPH Oxidases/deficiência , NADPH Oxidases/genética , RNA/isolamento & purificação , Fluxo Sanguíneo Regional , Estresse Mecânico , Superóxidos/metabolismo , Fatores de Tempo , Túnica Íntima/metabolismo , Túnica Íntima/patologia , Túnica Íntima/fisiopatologia , Vasodilatação , Vasodilatadores/farmacologia
11.
Am J Physiol Heart Circ Physiol ; 297(4): H1290-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19684182

RESUMO

Abdominal aortic aneurysms (AAA) localize in the infrarenal aorta in humans, while they are found in the suprarenal aorta in mouse models. It has been shown previously that humans experience a reversal of flow during early diastole in the infrarenal aorta during each cardiac cycle. This flow reversal causes oscillatory wall shear stress (OWSS) to be present in the infrarenal aorta of humans. OWSS has been linked to a variety of proatherogenic and proinflammatory factors. The presence of reverse flow in the mouse aorta is unknown. In this study we investigated blood flow in mice, using phase-contrast magnetic resonance (PCMR) imaging. We measured blood flow in the suprarenal and infrarenal abdominal aorta of 18 wild-type C57BL/6J mice and 15 apolipoprotein E (apoE)-/- mice. Although OWSS was not directly evaluated, results indicate that, unlike humans, there is no reversal of flow in the infrarenal aorta of wild-type or apoE-/- mice. Distensibility of the mouse aortic wall in both the suprarenal and infrarenal segments is higher than reported values for the human aorta. We conclude that normal mice do not experience the reverse flow in the infrarenal aorta that is observed in humans.


Assuntos
Aorta Abdominal/fisiologia , Aneurisma da Aorta Abdominal/fisiopatologia , Cineangiografia , Angiografia por Ressonância Magnética , Animais , Aorta Abdominal/anatomia & histologia , Aneurisma da Aorta Abdominal/patologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Velocidade do Fluxo Sanguíneo , Elasticidade , Humanos , Interpretação de Imagem Assistida por Computador , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fluxo Pulsátil , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Especificidade da Espécie , Estresse Mecânico
12.
Math Biosci Eng ; 17(1): 418-441, 2019 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-31731359

RESUMO

In this paper, we consider a diffusive SIS epidemic reaction-diffusion model with linear source in a heterogeneous environment in which the frequency-dependent incidence function is SI/(c + S + I) with c a positive constant. We first derive the uniform bounds of solutions, and the uniform persistence property if the basic reproduction number $\mathcal{R}_{0}>1$. Then, in some cases we prove that the global attractivity of the disease-free equilibrium and the endemic equilibrium. Lastly, we investigate the asymptotic profile of the endemic equilibrium (when it exists) as the diffusion rate of the susceptible or infected population is small. Compared to the previous results [1, 2] in the case of c=0, some new dynamical behaviors appear in the model studied here; in particular, $\mathcal{R}_{0}$ is a decreasing function in c∈[0, ∞) and the disease dies out once c is properly large. In addition, our results indicate that the linear source term can enhance the disease persistence.


Assuntos
Número Básico de Reprodução , Doenças Transmissíveis/transmissão , Epidemias , Doenças Transmissíveis/epidemiologia , Simulação por Computador , Suscetibilidade a Doenças/epidemiologia , Transmissão de Doença Infecciosa , Humanos , Incidência , Modelos Biológicos , Dinâmica Populacional
13.
J Med Chem ; 62(10): 4979-4990, 2019 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-31021628

RESUMO

Phosphodiesterase type 5 (PDE5) inhibitors are first-line therapy for pulmonary arterial hypertension (PAH) and erectile dysfunction. As a continuing work to improve the terminal half-lives and oral bioavailabilities of our previously reported 4(3 H)-pyrimidones, a pharmacokinetics-driven optimization focusing on the terminal substituent is described. Two major congeneric series of 4(3 H)-pyrimidones, the aminosulfonylphenylpyrimidones and acylaminophenylpyrimidones, were designed, synthesized, and pharmacologically assessed in vitro and in vivo. Among them, compound 15 (TPN171) with subnanomolar potency for PDE5 and good selectivity over PDE6 was finally recognized as a potential drug candidate, and its pharmacokinetic profiles in rats and dogs are significantly improved compared to the starting compound (3). Moreover, TPN171 was proven to exert a longer lasting effect than sildenafil in animal models, providing a foundation for a once-daily oral administration for its clinical use. TPN171 is currently being investigated in a phase II clinical trial for the treatment of PAH.


Assuntos
Hipertensão Pulmonar/tratamento farmacológico , Inibidores da Fosfodiesterase 5/farmacologia , Inibidores da Fosfodiesterase 5/farmacocinética , Pirimidinas/farmacologia , Pirimidinas/farmacocinética , Animais , Cães , Desenho de Fármacos , Feminino , Meia-Vida , Masculino , Inibidores da Fosfodiesterase 5/síntese química , Pirimidinas/síntese química , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Citrato de Sildenafila/farmacologia , Relação Estrutura-Atividade , Especificidade por Substrato
14.
Circulation ; 116(11): 1258-66, 2007 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-17785623

RESUMO

BACKGROUND: Exposure to disturbed flow, including oscillatory shear stress, stimulates endothelial cells (ECs) to produce bone morphogenic protein (BMP) 4, which in turn activates inflammation, a critical atherogenic step. BMP activity is regulated by the level of BMP antagonists. Until now it was not known whether shear also regulates the expression of BMP antagonists and whether they play a role in EC pathophysiology. METHODS AND RESULTS: BMP antagonists follistatin, noggin, and matrix Gla protein were expressed in cultured bovine and human arterial ECs. Surprisingly, oscillatory shear stress increased expression of the BMP antagonists in ECs, whereas unidirectional laminar shear decreased such expression. Immunohistochemical studies with mouse aortas showed data consistent with in vitro findings: Only ECs in the lesser curvature exposed to disturbed flow, but not those in the greater curvature and straight arterial regions exposed to undisturbed flow, showed coexpression of BMP4 and the BMP antagonists. Similarly, in human coronary arteries, expression of BMP4 and BMP antagonists in ECs positively correlated with the severity of atherosclerosis. Monocyte adhesion induced by oscillatory shear stress was inhibited by knockdown of BMP4 or treatment with recombinant follistatin or noggin, whereas it was increased by knockdown of follistatin and/or noggin. CONCLUSIONS: The present results suggest that ECs coexpress BMP antagonists along with BMP4 in an attempt to minimize the inflammatory response by oscillatory shear stress as part of a negative feedback mechanism. The balance between the agonist, BMP4, and its antagonists may play an important role in the overall control of inflammation and atherosclerosis.


Assuntos
Aorta/metabolismo , Aterosclerose/metabolismo , Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Proteínas Morfogenéticas Ósseas/biossíntese , Vasos Coronários/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Animais , Aorta/patologia , Aterosclerose/genética , Velocidade do Fluxo Sanguíneo/fisiologia , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/genética , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Bovinos , Células Cultivadas , Células Endoteliais/patologia , Endotélio Vascular/patologia , Folistatina/biossíntese , Folistatina/genética , Regulação da Expressão Gênica/fisiologia , Humanos , Inflamação/genética , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Resistência ao Cisalhamento
15.
Arterioscler Thromb Vasc Biol ; 27(2): 346-51, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17122449

RESUMO

OBJECTIVE: The hemodynamic environment is a determinant of susceptibility to atherosclerosis in the vasculature. Although mouse models are commonly used in atherosclerosis studies, little is known about local variations in wall shear stress (WSS) in the mouse and whether the levels of WSS are comparable to those in humans. The objective of this study was to determine WSS values in the mouse aorta and to relate these to expression of gene products associated with atherosclerosis. METHODS AND RESULTS: Using micro-CT and ultrasound methodologies we developed a computational fluid dynamics model of the mouse aorta and found values of WSS to be much larger than those for humans. We also used a quantum dot-based approach to study vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 expression on the aortic intima and demonstrated that increased expression for these molecules occurs where WSS was relatively low for the mouse. CONCLUSIONS: Despite large differences in WSS in the two species, the spatial distributions of atherogenic molecules in the mouse aorta are similar to atherosclerotic plaque localization found in human aortas. These results suggest that relative differences in WSS or in the direction of WSS, as opposed to the absolute magnitude, may be relevant determinants of flow-mediated inflammatory responses.


Assuntos
Aorta Torácica/fisiopatologia , Aterosclerose/fisiopatologia , Resistência Vascular/fisiologia , Animais , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Simulação por Computador , Regulação da Expressão Gênica , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Matemática , Camundongos , Camundongos Endogâmicos C57BL , Fluxo Sanguíneo Regional/fisiologia , Fatores de Risco , Estresse Mecânico , Túnica Íntima/metabolismo , Túnica Íntima/patologia , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
16.
Zhonghua Gan Zang Bing Za Zhi ; 15(12): 910-3, 2007 Dec.
Artigo em Zh | MEDLINE | ID: mdl-18171525

RESUMO

OBJECTIVES: To detect the expressions of Tec tyrosine kinase in hepatocellular carcinoma and the levels of phosphorylation of tyrosine kinase in liver cancer tissues, paracancerous tissues and normal liver tissues and to find the significance of their differences. METHODS: 200 specimens of tissues, including liver cancer tissues, surrounding liver tissues not more than 1.5 cm from the cancers, and normal liver tissues were investigated for Tec protein expression and Tec phosphorylation by tissue microarrays and immunohistochemistry (SP method). RESULTS: The positive immunohistochemical stainings of Tec in cancerous tissues and non-cancerous tissues showed no obvious differences, nevertheless, the immunostaining levels in liver cancer tissues were much higher than in non-cancerous tissues and they correlated with the grading of tumors (P < 0.05). The phosphorylation of Tec was significantly expressed in liver cancer tissues (73%) in comparison with other tissues (42%, 10% both P < 0.05), but it did not correlate with any clinicopathological characteristics. CONCLUSION: Overexpression of Tec is associated with the tumorigenesis and development of liver cancer; inhibiting Tec or degrading Tec phosphorylation directly might affect the progression of liver cancer.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Tirosina Quinases/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Fosforilação , Proteínas Tirosina Quinases/genética
17.
R Soc Open Sci ; 3(7): 160298, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27493783

RESUMO

To delineate the influence of hemodynamic force on cell adhesion processes, model in vitro fluidic assays that mimic physiological conditions are commonly employed. Herein, we offer a framework for solution of the three-dimensional Navier-Stokes equations using computational fluid dynamics (CFD) to estimate the forces resulting from fluid flow near a plane acting on a sphere that is either stationary or in free flow, and we compare these results to a widely used theoretical model that assumes Stokes flow with a constant shear rate. We find that while the full three-dimensional solutions using a parabolic velocity profile in CFD simulations yield similar translational velocities to those predicted by the theoretical method, the CFD approach results in approximately 50% larger rotational velocities over the wall shear stress range of 0.1-5.0 dynes cm(-2). This leads to an approximately 25% difference in force and torque calculations between the two methods. When compared with experimental measurements of translational and rotational velocities of microspheres or cells perfused in microfluidic channels, the CFD simulations yield significantly less error. We propose that CFD modelling can provide better estimations of hemodynamic force levels acting on perfused microspheres and cells in flow fields through microfluidic devices used for cell adhesion dynamics analysis.

18.
Int J Cardiovasc Imaging ; 32(9): 1327-1336, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27229349

RESUMO

Wall shear stress (WSS) has been investigated as a prognostic marker for the prospective identification of rapidly progressing coronary artery disease (CAD) and atherosclerotic lesions likely to gain high-risk (vulnerable) characteristics. The goal of this study was to compare biplane angiographic vs. intravascular ultrasound (IVUS) derived reconstructed coronary geometries to evaluate agreement in geometry, computed WSS, and association of WSS and CAD progression. Baseline and 6-month follow-up angiographic and IVUS imaging data were collected in patients with non-obstructive CAD (n = 5). Three-dimensional (3D) reconstructions of the coronary arteries were generated with each technique, and patient-specific computational fluid dynamics models were constructed to compute baseline WSS values. Geometric comparisons were evaluated in arterial segments (n = 9), and hemodynamic data were evaluated in circumferential sections (n = 468). CAD progression was quantified from serial IVUS imaging data (n = 277), and included virtual-histology IVUS (VH-IVUS) derived changes in plaque composition. There was no significant difference in reconstructed coronary segment lengths and cross-sectional areas (CSA), however, IVUS derived geometries exhibited a significantly larger left main CSA than the angiographic reconstructions. Computed absolute time-averaged WSS (TAWSSABS) values were significantly greater in the IVUS derived geometries, however, evaluations of relative TAWSS (TAWSSREL) values revealed improved agreement and differences within defined zones of equivalence. Associations between VH-IVUS defined CAD progression and angiographic or IVUS derived WSS exhibited poor agreement when examining TAWSSABS data, but improved when evaluating the association with TAWSSREL data. We present data from a small cohort of patients highlighting strong agreement between angiographic and IVUS derived coronary geometries, however, limited agreement is observed between computed WSS values and associations of WSS with CAD progression.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Circulação Coronária , Vasos Coronários/diagnóstico por imagem , Hemodinâmica , Imageamento Tridimensional/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Ultrassonografia de Intervenção/métodos , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/fisiopatologia , Progressão da Doença , Humanos , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Placa Aterosclerótica , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estresse Mecânico , Fatores de Tempo
19.
Life Sci ; 71(22): 2595-602, 2002 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-12354578

RESUMO

Morphine causes immunosuppression by binding to opioid receptors on immune cells, or indirectly by acting on receptors in the brain. However, morphine exact mechanism of action has not been elucidated. In the present study, we investigated the role of glucocorticoids in morphine-mediated immunosuppression after acute action in the rat mesencephalon periaqueductal gray (PAG). Natural killer (NK) cell activity and T cell proliferation were used to evaluate potential indirect mechanisms of morphine action. Microinjection of morphine in the ventral-caudal aspect of the PAG significantly (p < 0.01) suppressed splenic NK cell cytotoxic activity (32% reduction), and antiTCR-, IL-2-, antiTCR + IL-2, and Con A-induced thymic (30% to 50% reduction) and splenic (35% to 70% reduction) lymphocyte proliferation compared with PAG-injected saline control animals. The glucocorticoid receptor antagonist mifepristone (RU 486) did not block the immunosuppressive effects of morphine, suggesting that such effects are independent of activation of the hypothalamic-pituitary-adrenal axis.


Assuntos
Antagonistas de Hormônios/farmacologia , Imunossupressores/antagonistas & inibidores , Imunossupressores/farmacologia , Mifepristona/farmacologia , Morfina/antagonistas & inibidores , Morfina/farmacologia , Animais , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Glucocorticoides/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Masculino , Substância Cinzenta Periaquedutal/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
20.
Atherosclerosis ; 232(2): 271-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24468138

RESUMO

AIMS: Large plaque burden, certain phenotypes, and low wall shear stress (WSS) are associated with adverse outcomes and high WSS with development of plaque vulnerability. We aimed to investigate the incremental value of the combination of plaque burden, WSS and plaque phenotype for prediction of coronary atherosclerotic plaque progression and vulnerability. METHODS: Twenty patients with CAD underwent baseline and 6-month follow-up coronary virtual histology-intravascular ultrasound (VH-IVUS) and computational fluid dynamics modeling for calculation of WSS. Low WSS was defined as <10 dynes/cm(2) and high WSS as ≥25 dynes/cm(2). Baseline plaque characteristics and WSS were related to plaque progression and vulnerability. RESULTS: In 2249 VH-IVUS frames analyzed, coronary segments with both plaque burden >40% and low WSS had significantly greater change in plaque area at follow-up (+0.68 ± 1.05 mm(2)), compared to segments with plaque burden >40% without low WSS (-0.28 ± 1.32 mm(2)) or segments with low WSS and plaque burden ≤40% (+0.05 ± 0.71 mm(2)) (p = 0.047). Among plaque phenotypes, pathologic intimal thickening (PIT) had the greatest increase in necrotic core (NC) area (p = 0.06) and greatest decrease in fibro-fatty (FF) area (p < 0.0001). At follow-up, compared to segments with either plaque burden >60%, PIT, or high WSS, those with a combination of plaque burden >60%, PIT, and high WSS developed greater increase in NC area (p = 0.002), greater decrease in FF (p = 0.004) and fibrous areas (p < 0.0001), and higher frequency of expansive remodeling (p = 0.019). CONCLUSION: Combination of plaque burden, WSS, and plaque phenotype has incremental value for prediction of coronary plaque progression and increased plaque vulnerability in patients with non-obstructive CAD.


Assuntos
Doença da Artéria Coronariana/patologia , Endotélio Vascular/patologia , Placa Aterosclerótica/patologia , Idoso , Doença da Artéria Coronariana/diagnóstico por imagem , Progressão da Doença , Endotélio Vascular/diagnóstico por imagem , Feminino , Humanos , Hidrodinâmica , Masculino , Pessoa de Meia-Idade , Fenótipo , Placa Aterosclerótica/diagnóstico por imagem , Prognóstico , Resistência ao Cisalhamento , Estresse Mecânico , Ultrassonografia de Intervenção
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