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1.
Exp Cell Res ; 437(1): 113998, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38513962

RESUMO

Plasma saturated free fatty acid (FFA)-induced endothelial dysfunction (ED) contributes to the pathogenesis of atherosclerosis and cardiovascular diseases. However, the mechanism underlying saturated FFA-induced ED remains unclear. This study demonstrated that palmitic acid (PA) induced ED by activating the NADPH oxidase (NOX)/ROS signaling pathway to activate protein phosphatase 4 (PP4) and protein phosphatase 2A (PP2A), thereby reducing endothelial nitric oxide synthase (eNOS) phosphorylation at Ser633 and Ser1177, respectively. Okadaic acid (OA) and fostriecin (FST), which are inhibitors of PP2A, inhibited the PA-induced decreases in eNOS phosphorylation at Ser633 and Ser1177. The antioxidants N-acetylcysteine (NAC) and apocynin (APO) or knockdown of gp91phox or p67phox (NOX subunits) restored PA-mediated downregulation of PP4R2 protein expression and eNOS Ser633 phosphorylation. Knockdown of the PP4 catalytic subunit (PP4c) specifically increased eNOS Ser633 phosphorylation, while silencing the PP2A catalytic subunit (PP2Ac) restored only eNOS Ser1177 phosphorylation. Furthermore, PA dramatically decreased the protein expression of the PP4 regulatory subunit R2 (PP4R2) but not the other regulatory subunits. PP4R2 overexpression increased eNOS Ser633 phosphorylation, nitric oxide (NO) production, cell migration and tube formation but did not change eNOS Ser1177 phosphorylation levels. Coimmunoprecipitation (Co-IP) suggested that PP4R2 and PP4c interacted with the PP4R3α and eNOS proteins. In summary, PA decreases PP4R2 protein expression through the Nox/ROS pathway to activate PP4, which contributes to ED by dephosphorylating eNOS at Ser633. The results of this study suggest that PP4 is a novel therapeutic target for ED and ED-associated vascular diseases.


Assuntos
Óxido Nítrico Sintase Tipo III , Fosfoproteínas Fosfatases , Doenças Vasculares , Humanos , Fosforilação , Óxido Nítrico Sintase Tipo III/metabolismo , Ácido Palmítico/farmacologia , Serina/metabolismo , Espécies Reativas de Oxigênio , Células Cultivadas , Proteína Fosfatase 2/metabolismo , Óxido Nítrico/metabolismo
2.
Virol J ; 20(1): 244, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37885034

RESUMO

BACKGROUND: Foamy viruses (FVs) are unique nonpathogenic retroviruses, which remain latent in the host for a long time. Therefore, they may be safe, effective gene transfer vectors. In this study, were assessed FV-host cell interactions and the molecular mechanisms underlying FV latent infection. METHODS: We used the prototype FV (PFV) to infect HT1080 cells and a PFV indicator cell line (PFVL) to measure virus titers. After 48 h of infection, the culture supernatant (i.e., cell-free PFV particles) and transfected cells (i.e., cell-associated PFV particles) were harvested and incubated with PFVL. After another 48 h, the luciferase activity was used to measure virus titers. RESULTS: Through transcriptomics sequencing, we found that PREB mRNA expression was significantly upregulated. Moreover, PREB overexpression reduced PFV replication, whereas endogenous PREB knockdown increased PFV replication. PREB interacted with the Tas DNA-binding and transcriptional activation domains and interfered with its binding to the PFV long terminal repeat and internal promoter, preventing the recruitment of transcription factors and thereby inhibiting the transactivation function of Tas. PREB C-terminal 329-418 aa played a major role in inhibiting PFV replication; PREB also inhibited bovine FV replication. Therefore, PREB has a broad-spectrum inhibitory effect on FV replication. CONCLUSIONS: Our results demonstrated that PREB inhibits PFV replication by impeding its transcription.


Assuntos
Spumavirus , Animais , Bovinos , Spumavirus/genética , Spumavirus/metabolismo , Fatores de Transcrição/metabolismo , Linhagem Celular , Domínios Proteicos , Retroviridae , Replicação Viral
3.
Virol J ; 19(1): 195, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36419065

RESUMO

BACKGROUND: Foamy viruses (FVs) are retroviruses with unique replication strategies that cause lifelong latent infections in their hosts. FVs can also produce foam-like cytopathic effects in vitro. However, the effect of host cytokines on FV replication requires further investigation. Although interferon induced transmembrane (IFITMs) proteins have become the focus of antiviral immune response research due to their broad-spectrum antiviral ability, it remains unclear whether IFITMs can affect FV replication. METHOD: In this study, the PFV virus titer was characterized by measuring luciferase activity after co-incubation of PFVL cell lines with the cell culture supernatants (cell-free PFV) or the cells transfected with pcPFV plasmid/infected with PFV (cell-associated PFV). The foam-like cytopathic effects of PFV infected cells was observed to reflect the virus replication. The total RNA of PFV infected cells was extracted, and the viral genome was quantified by Quantitative reverse transcription PCR to detect the PFV entry into target cells. RESULTS: In the present study, we demonstrated that IFITM1-3 overexpression inhibited prototype foamy virus (PFV) replication. In addition, an IFITM3 knockdown by small interfering RNA increased PFV replication. We further demonstrated that IFITM3 inhibited PFV entry into host cells. Moreover, IFITM3 also reduced the number of PFV envelope proteins, which was related to IFITM3 promoted envelope degradation through the lysosomal pathway. CONCLUSIONS: Taken together, these results demonstrate that IFITM3 inhibits PFV replication by inhibiting PFV entry into target cells and reducing the number of PFV envelope.


Assuntos
Spumavirus , Viroses , Humanos , Antivirais/metabolismo , Spumavirus/genética , Replicação Viral , Linhagem Celular , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
4.
Int J Clin Pract ; 2022: 8975396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814306

RESUMO

Objective: The present study aims to investigate the relationship between vitamin D deficiency and renin-angiotensin-aldosterone levels in patients with essential hypertension. Methods: The present study observed two groups of patients from Urumqi, Xinjiang, China, from April 2017 to March 2018. There were two subject groups: the hypertension group (80 patients with essential hypertension selected by random cluster sampling) and the control group (76 healthy adults). The 25-hydroxyvitamin D (25(OH)D or vitamin D) levels were measured through electrolytes; fasting blood glucose, blood lipids, and other biochemical indicators were detected using immune chemiluminescence; and plasma renin activity and angiotensin II concentrations were detected with radio-immunity. Results: Comparison between the hypertension group and control group showed statistically significant differences in the systolic pressure and levels of 25(OH)D, renin, and triglycerides (P < 0.05). The correlation analysis showed that 25(OH)D was negatively correlated with renin (r = -0.185; P=0.021) and positively correlated with systolic pressure (r = -0.105; P=0.035). There were no statistically significant differences in diastolic pressure, fasting blood glucose, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides between the two groups. Conclusions: The results of the present study show that vitamin D deficiency is common in Urumqi, Xinjiang, China and vitamin D levels are negatively correlated with renin levels. Vitamin D plays an important role in regulating blood pressure by affecting renin levels through the renin-angiotensin-aldosterone system.


Assuntos
Angiotensinas , Hipertensão Essencial , Renina , Deficiência de Vitamina D , Adulto , Aldosterona/sangue , Angiotensinas/sangue , Povo Asiático , Pressão Sanguínea , Hipertensão Essencial/sangue , Hipertensão Essencial/complicações , Hipertensão Essencial/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Renina/sangue , Deficiência de Vitamina D/complicações
5.
Neurobiol Dis ; 154: 105339, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33775822

RESUMO

Moyamoya-like vasculopathy, the "puff of smoke"-like small vessels in the brain, is initially identified in patients with Moyamoya disease (MMD), a rare cerebrovascular disease, and later found in patients with various types of neurological conditions, including Down syndrome, Stroke, and vascular dementia. It is thus of interest to understand how this vasculopathy is developed. Here, we provided evidence for cortical astrocytic neogenin (NEO1) deficiency to be a risk factor for its development. NEO1, a member of deleted in colorectal cancer (DCC) family netrin receptors, was reduced in brain samples of patients with MMD. Astrocytic Neo1-loss resulted in an increase of small blood vessels (BVs) selectively in the cortex. These BVs were dysfunctional, with leaky blood-brain barrier (BBB), thin arteries, and accelerated hyperplasia in veins and capillaries, resembled to the features of moyamoya-like vasculopathy. Additionally, we found that both MMD patient and Neo1 mutant mice exhibited altered gene expression in their cortex in proteins critical for not only angiogenesis [e.g., an increase in vascular endothelial growth factor (VEGFa)], but also axon guidance (e.g., netrin family proteins) and inflammation. In aggregates, these results suggest a critical role of astrocytic NEO1-loss in the development of Moyamoya-like vasculopathy, providing a mouse model for investigating mechanisms of Moyamoya-like vasculopathy.


Assuntos
Astrócitos/metabolismo , Barreira Hematoencefálica/metabolismo , Proteínas de Membrana/deficiência , Doença de Moyamoya/metabolismo , Córtex Pré-Frontal/metabolismo , Adulto , Animais , Astrócitos/patologia , Barreira Hematoencefálica/patologia , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Doença de Moyamoya/genética , Doença de Moyamoya/patologia , Córtex Pré-Frontal/patologia
6.
J Integr Neurosci ; 20(2): 393-397, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34258938

RESUMO

Epilepsy is a common heterogeneous group of neurological disorders including electroencephalographic and brain imaging. We used whole exome sequencing and whole genome sequencing to identify variants in a pedigree associated with epilepsy. Cranium CT scan showed that the lateral right parietal lobe was hyperdense, and there were no clear boundaries with brain tissue in affected cases. Using WES, one exclusive nonsynonymous mutant in gene TSC2 (Chr16:2138307; c.5240 T > G; p.Ile1747Ser) was involved in this disease. Further analysis showed that de novo variant in TSC2 was high conserved across different species. Moreover, the two affected sisters and their father had the same compound heterozygous variants in TSC2, while the father had no epilepsy but depigmentation. These variants demonstrated that variant in TSC2 may result in epilepsy with incomplete penetrance in humans, and the CNV and SV variants we identified probably be involved in this disease.


Assuntos
Síndromes Epilépticas/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Sequenciamento Completo do Genoma , Adulto , Pré-Escolar , Síndromes Epilépticas/diagnóstico por imagem , Síndromes Epilépticas/fisiopatologia , Feminino , Humanos , Masculino , Linhagem , Sequenciamento do Exoma
7.
IUBMB Life ; 72(9): 2045-2055, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32687247

RESUMO

Parkinson's disease (PD) is one of the most common neurodegenerative disorders. Long non-coding RNAs have important regulatory values in various human diseases. Non-coding RNA Activated by DNA Damage (NORAD) was reported to regulate PD progression in vitro, but its functional mechanism is fully unknown. We used 1-methyl-4-phenylpyridinium (MPP+ ) to establish the cell-based PD model. NORAD, microRNA-204-5p (miR-204-5p), and solute carrier family 5 member 3 (SLC5A3) levels were quantified using the quantitative real-time polymerase chain reaction. Cell viability and apoptosis were determined by Cell Counting Kit-8 and flow cytometry, respectively. The protein levels were analyzed via western blot. Cytotoxicity was assessed by the released lactate dehydrogenase level in cell supernatant. Oxidative stress and inflammation were measured by the standard indicators. Dual-luciferase reporter and RNA immunoprecipitation assays were performed for intergenic combination. First, we found that NORAD was obviously reduced in MPP+ -treated neuroblastoma cells and lightened the MPP+ -induced cytotoxicity, oxidative stress, and inflammatory response. Then, NORAD was shown to be a miR-204-5p sponge and avoided the injury induced by MPP+ in neuroblastoma cells via targeting miR-204-5p. SLC5A3 was a miR-204-5p target and could be regulated by NORAD/miR-204-5p axis. SLC5A3 knockdown assuaged the anti-miR-204-5p-induced protection for neuroblastoma cells from MPP+ . Altogether, NORAD played a neuroprotective role against the progression of MPP+ -induced PD model in neuroblastoma cells relying on the miR-204-5p/SLC5A3 axis. This study afforded the clear elaboration on the PD pathomechanism concerning NORAD.


Assuntos
Regulação da Expressão Gênica , Proteínas de Choque Térmico/metabolismo , MicroRNAs/genética , Neuroblastoma/prevenção & controle , Estresse Oxidativo , Doença de Parkinson/prevenção & controle , RNA Longo não Codificante/genética , Simportadores/metabolismo , 1-Metil-4-fenilpiridínio/toxicidade , Animais , Apoptose , Proliferação de Células , Sobrevivência Celular , Proteínas de Choque Térmico/genética , Humanos , Camundongos , Neuroblastoma/induzido quimicamente , Neuroblastoma/patologia , Doença de Parkinson/etiologia , Doença de Parkinson/patologia , Transdução de Sinais , Simportadores/genética , Células Tumorais Cultivadas
8.
Inflamm Res ; 69(5): 523-532, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32170348

RESUMO

OBJECTIVE: Myocardial infarction (MI) is one of the primary causes leading to heart failure in coronary artery disease. However, the mechanisms of macrophage that dominate pathogenesis of MI remain unclear. METHODS: Mice were induced with MI and pretreated with adenovirus containing indicated shRNA. Post-MI injuries were evaluated by echocardiography. BMDMs and post-MI LV macrophages were used to assess the significance of CXCR7. Macrophages' migration was examined by chemotaxis assay, Cytokine production, phosphorylation of ERK1/2, p38 MAPK and JNK were measured by ELISA. RESULTS: CXCR7 in macrophages was up-regulated during M1 polarization and following MI in the murine model, with positive correlation with M1 markers but not M2 markers. Besides, CXCR7 down-regulation abolished macrophage M1 polarization. In addition, CXCR7 but not CXCR3 or CXCR4 controlled SDF-1 and I-TAC-mediated chemotaxis and inflammation in M1-like macrophages post-MI, signaling through activating ERK1/2, whereas p38 MAPK and JNK were not involved. Moreover, silencing CXCR7 ameliorated cardiac dysfunction by attenuating infarct area, LVEF and LVFS post-MI along with reduction of CXCR7 expression and ERK1/2 phosphorylation. CONCLUSIONS: Our data demonstrate that CXCR7 suppression inhibits macrophages M1 polarization, chemotaxis and inflammation to ameliorate post-MI injury, providing novel insights and promising therapy approaches in post-MI treatment.


Assuntos
Macrófagos/imunologia , Infarto do Miocárdio/imunologia , Receptores CXCR/imunologia , Animais , Quimiotaxia , Citocinas/imunologia , Sistema de Sinalização das MAP Quinases , Macrófagos/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/genética , Infarto do Miocárdio/fisiopatologia , Fenótipo , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Receptores CXCR/genética
9.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 49(4): 439-446, 2020 Aug 25.
Artigo em Zh | MEDLINE | ID: mdl-32985156

RESUMO

OBJECTIVE: To investigate the expression of transient receptor potential canonical channels (TRPCs) in the heart and kidney of rat model of obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: Eighteen male SD rats were randomly assigned to intermittent hypoxia (IH) group (n=9 ) and control group (n=9). In IH group, rats were placed in a chamber and exposed to intermittent hypoxia for 8h (10AM-6PM) daily. The expression of TRPC-related mRNA and protein in the heart and kidney tissue were detected by qRT-PCR and Western blotting, respectively. RESULTS: The mRNA expressions of TRPC3/TRPC4/TRPC5 in heart tissues of IH group were increased significantly compared with the control group (all P>0.05); while there were no significant differences in the mRNA expressions of TRPC1/TRPC3/TRPC4/TRPC5/TRPC6/TRPC7 in kidney tissue between two groups (all P<0.05). The mRNA expressions of TRPC4, TRPC5 and TRPC6 in kidney tissues of IH group were lower than that in heart tissues (all P<0.05). The mRNA expression of TRPC7 in kidney tissues of control group was significantly higher than that in heart tissues (P<0.05). The expression of TRPC5 protein in heart tissues of IH group was significantly higher than that in the control group (P<0.05); while there was no significant differences in the expression of TRPC5/TRPC6/TRPC7 protein in kidney tissue between two groups (all P>0.05). CONCLUSIONS: The IH rat model shows that TRPC5 channel is likely to be involved in the OSAHS induced pathophysiological changes in the myocardium and may become a target to prevent OSAHS related cardiac damage.


Assuntos
Traumatismos Cardíacos , Rim , Apneia Obstrutiva do Sono , Canais de Cátion TRPC , Animais , Traumatismos Cardíacos/genética , Rim/lesões , Masculino , RNA Mensageiro/genética , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Apneia Obstrutiva do Sono/genética , Canais de Cátion TRPC/genética
10.
Microb Pathog ; 135: 103651, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31398532

RESUMO

Bartonella infection is distributed worldwide with animal and public health. Recent studies have shown that host cells infection by Bartonella has a series of different infection stages, beginning with encounter and adherence to the cells. In this study, we expressed and purified recombinant Bartonella henselae (B. henselae) α-enolase. And we found that B. henselae α-enolase is highly conserved in Bartonella species. The interacting protein partners of B. henselae α-enolase were showed by String-11. The interactions between B. henselae α-enolase and human plasminogen were subsequently confirmed by ELISA, pull down, T7 phage display and molecular docking assays. And the plasminogen-binding sites of B. henselae α-enolase are predicted at 247FYKNGSYFY255. These findings will help elucidate and improve the understanding of the molecular mechanisms of Bartonella infection.


Assuntos
Bartonella/enzimologia , Bartonella/genética , Proteínas de Transporte/metabolismo , Fosfopiruvato Hidratase/genética , Fosfopiruvato Hidratase/isolamento & purificação , Plasminogênio/metabolismo , Sequência de Aminoácidos , Bartonella henselae/enzimologia , Bartonella henselae/genética , Sítios de Ligação , Proteínas de Transporte/química , Clonagem Molecular , Regulação Bacteriana da Expressão Gênica , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Fosfopiruvato Hidratase/química , Fosfopiruvato Hidratase/classificação , Filogenia , Plasminogênio/química , Proteínas Recombinantes
11.
Med Sci Monit ; 25: 3390-3396, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31064975

RESUMO

BACKGROUND This study aimed to explore the association of angiotensin converting enzyme (ACE) gene insertion/deletion polymorphisms with left ventricular hypertrophy (LVH) in Han and Uighur hypertension-OSAHS (obstructive sleep apnea hypopnea syndrome) patients in China. MATERIAL AND METHODS A total of 162 Han and 72 Uygur patients with hypertension-OSAHS were independently subdivided into an LVH group and a non-LVH (NLVH) group based on the left ventricular mass index. The insertion/deletion polymorphisms of ACE gene were determined by polymerase chain reaction. The association of ACE gene insertion/deletion polymorphisms with LVH was assessed by chi-squared test. Logistic regression analysis was performed to obtain the odds ratios and 95% confidence intervals for the risk of LVH after adjusting for confounding factors. RESULTS In Uighur patients, the distributions of D allele and DD genotype showed significant differences between the LVH group and the NLVH group. The difference of DD genotype remained significant after multivariate adjustment. In contrast, no significant differences were observed in the distributions of D allele and DD genotype between the LVH group and the NLVH group in Han patients. Moreover, moderate-severe OSAHS was an independent risk factor for LVH. CONCLUSIONS D allele and DD genotype of ACE gene are possible genetic markers for the risk of LVH in Uighur but not Han hypertension-OSAHS patients.


Assuntos
Hipertrofia Ventricular Esquerda/genética , Peptidil Dipeptidase A/genética , Apneia Obstrutiva do Sono/genética , Adulto , Alelos , Povo Asiático/genética , China , Etnicidade/genética , Feminino , Frequência do Gene/genética , Genótipo , Humanos , Hipertensão/complicações , Hipertensão/genética , Hipertrofia Ventricular Esquerda/fisiopatologia , Mutação INDEL/genética , Masculino , Pessoa de Meia-Idade , Peptidil Dipeptidase A/fisiologia , Reação em Cadeia da Polimerase , Polimorfismo Genético/genética , Fatores de Risco , Apneia Obstrutiva do Sono/complicações
12.
Clin Exp Hypertens ; 39(8): 685-690, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28872358

RESUMO

Patients with nondipper hypertension are known to carry a high risk of cardiovascular complications. Vitamin D deficiency is associated with hypertension. Because vitamin D deficiency activates the renin-angiotensin-aldosterone system (RAAS), we hypothesized that this vitamin would interact with the RAAS to influence blood pressure (BP) in nondipper hypertensive patients. We performed a cross-sectional analysis of 1,007 outpatients with hypertension (HTN). Dipper and nondipper patterns were detected, and the two groups were matched for clinical, laboratory, 25-hydroxyvitamin D (25OHD) levels, and ambulatory blood pressure recording. Plasma renin activity (PRA), angiotensin II, and plasma aldosterone concentration (PAC) were assessed in 174 patients treated with calcium channel blockers or no medication. The mean 25OHD concentration in the entire study population was 12.3ng/dL, and the prevalence of vitamin D deficiency was 87.0%. Dipper and nondipper HTN were noted in 187 patients (24.6%) and 573 patients (75.4%). 25OHD levels were similar between nondipper and dipper HTN groups. Forward stepwise logistic regression analysis showed that BMI and age were independent predictors of nondipper HTN. Neither 25OHD levels nor RAAS components were included in the model. In correlation analyses, nocturnal decline of diastolic BP was positively associated with 25OHD levels and standing PRA (r = 0.152 p = 0.045, r = 0.165 p = 0.038, respectively). The present study showed that vitamin D deficiency was astonishingly prevalent in hypertensive subjects residing in Xinjiang, China. There may be a weakly association of nocturnal DBP decline with 25OHD levels and standing PRA levels. We found no association between vitamin D deficiency and nondipper HTN.


Assuntos
Pressão Sanguínea , Ritmo Circadiano/fisiologia , Hipertensão/fisiopatologia , Renina/sangue , Deficiência de Vitamina D/fisiopatologia , Vitamina D/análogos & derivados , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Aldosterona/sangue , Angiotensina II/sangue , Monitorização Ambulatorial da Pressão Arterial , Índice de Massa Corporal , Estudos Transversais , Diástole , Feminino , Humanos , Hipertensão/sangue , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Postura/fisiologia , Sistema Renina-Angiotensina/fisiologia , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações
13.
Soft Matter ; 12(8): 2348-56, 2016 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-26791085

RESUMO

The actuation performance of dielectric elastomers (DEs) is affected by dissipation. In the present article, an analytical model is developed to investigate the dissipative performance of DEs by considering viscoelasticity and leakage current. Various voltage waveforms, such as DC voltage, square voltage, stepwise DC voltage, ramp voltage, sawtooth voltage, and triangular voltage, were applied to explore the dissipative performance of DEs. The DEs with diverse moduli and viscoelasticity intensities were also analyzed by comparing the different dissipative performances. Numerical calculations were employed to evaluate the dissipative behavior of DEs. When the value of the applied voltage is maintained invariable, the stretch gradually creeps, and the total current from the battery and the leakage current approach each other eventually. When the applied voltage varies linearly, the stretch deforms dramatically, and then the total current from the battery is much larger than the leakage current.

14.
Soft Matter ; 11(38): 7483-93, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26287474

RESUMO

This article describes the development of an analytical model to study the coupled nonlinear oscillation and stability evolution of viscoelastic dielectric elastomers (DEs) under non-equibiaxial tensile forces by utilizing the method of virtual work. Numerically calculated results are employed to predict this nonlinear dynamic behavior. The resonant frequency (where the amplitude-frequency response curve peaks) and the amplitude-frequency response of the deformation in both in-plane directions are tuned by varying the values of tensile force. The oscillation response in the two in-plane directions exhibits strong nonlinearity and coupling with each other, and is tuned by the changing tensile forces under a specific excitation frequency. By varying the values of tensile forces, the dynamic viscoelastic creep in a certain in-plane direction can be eliminated. Phase diagrams and Poincaré maps under several values of tensile forces are utilized to study the stability evolution of the DE system under non-equibiaxial tensile forces.

15.
Med Sci Monit ; 21: 44-51, 2015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25556925

RESUMO

BACKGROUND: The association of genetic polymorphisms of klotho gene with aging has not been thoroughly examined. Previous studies showed that longevity in the Uygurs was considerably greater than in Kazaks in Xinjiang. This study aimed to investigate the difference of renal function and Klotho gene polymorphisms between Kazak and Uygur normal populations in Xinjiang, China. MATERIAL/METHODS: A total of 249 Uygur and 386 Kazak clinically normal subjects were included in this study. Four single-nucleotide polymorphisms (rs1207568, rs564481, rs9527025, and rs9536314) of the klotho gene were genotyped using the ABI SNaPshot method. Estimated glomerular filtration rate (eGFR) was calculated according to the Chinese simplified MDRD equation. RESULTS: There were significant differences between Kazak and Uygur healthy populations in both allele frequencies and genotype distributions in rs9527025 and rs9536314 (P<0.05, respectively). When the subjects were divided into 2 groups according to the genotypes of the klotho gene polymorphism, in the GA+AA genotype distributions of the rs1207568, the differences I serum creatinine and estimated glomerular filtration rate between the Kazak and Uygur groups were statistically significant (P<0.05, respectively). In CC genotype of rs564481, serum creatinine was significantly higher in Kazaks compared with Uygurs (P<0.05). In GG genotype of rs9527025, serum creatinine was significantly higher in the Kazak group compared with the Uygur group (P<0.05), as well as in CG+CC genotype of rs9527025 (P<0.05). Serum creatinine was significantly higher in the Kazak group compared with the Uygur group in TT genotype of rs9536314 (P<0.05), as was GT+GG genotype of rs9536314. Haplotype analysis indicated that the frequencies of ACGT, GTGT, and GCCG haplotypes were significantly different between Kazak and Uygur healthy populations (P=0.04, P=0.018, P=0.000, respectively). CONCLUSIONS: Significant differences in klotho gene rs9527025 and rs9536314 polymorphisms were found between the Uygur and Kazak populations.


Assuntos
Glucuronidase/genética , Rim/metabolismo , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , China/etnologia , Etnicidade , Feminino , Frequência do Gene , Genótipo , Taxa de Filtração Glomerular , Haplótipos , Humanos , Testes de Função Renal , Proteínas Klotho , Masculino , Pessoa de Meia-Idade , Mutação
16.
Front Nutr ; 11: 1421848, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38962449

RESUMO

Introduction: Dietary advanced lipoxidation end products (ALEs), which are abundant in heat-processed foods, could induce lipid metabolism disorders. However, limited studies have examined the relationship between maternal ALEs diet and offspring health. Methods: To investigate the transgenerational effects of ALEs, a cross-generation mouse model was developed. The C57BL/6J mice were fed with dietary ALEs during preconception, pregnancy and lactation. Then, the changes of glycolipid metabolism and gut microbiota of the offspring mice were analyzed. Results: Maternal ALEs diet not only affected the metabolic homeostasis of dams, but also induced hepatic glycolipid accumulation, abnormal liver function, and disturbance of metabolism parameters in offspring. Furthermore, maternal ALEs diet significantly upregulated the expression of TLR4, TRIF and TNF-α proteins through the AMPK/mTOR/PPARα signaling pathway, leading to dysfunctional glycolipid metabolism in offspring. In addition, 16S rRNA analysis showed that maternal ALEs diet was capable of altered microbiota composition of offspring, and increased the Firmicutes/Bacteroidetes ratio. Discussion: This study has for the first time demonstrated the transgenerational effects of maternal ALEs diet on the glycolipid metabolism and gut microbiota in offspring mice, and may help to better understand the adverse effects of dietary ALEs.

17.
Polymers (Basel) ; 16(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39000759

RESUMO

The current polyvinyl chloride (PVC) gel flexible actuators are facing challenges of high input voltage and an insufficient elastic modulus. In this study, we conducted a detailed study on the properties of PVC gel prepared by introducing the modifier polyvinyl chloride-vinyl acetate (P(VC-VA)). We compared a modified PVC gel with the traditional one in terms of the relative dielectric constant, mechanical modulus, and electromechanical actuation performance. Experimental results demonstrated that the introduction of P(VC-VA) enhanced the dielectric constant and reduced the driving electric field strength of PVC gels. The dielectric constant increased from 4.77 to 7.3. The electromechanical actuation performance increased by 150%. We employed the Gent model to fit the experimental results, and the actual experimental data aligned well with the expectations of the Gent model. The research results show that this type of plasticizing method effectively balanced the mechanical and electrical performance of PVC gels. This study summarizes the experimental results and performance analysis of PVC gels prepared using innovative plasticization methods, revealing the potential engineering applications of polymeric gels.

18.
Heliyon ; 9(2): e13731, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36816282

RESUMO

In recent years, COVID-19 has spread across the whole world, and manpowered collection of pharyngeal samples undoubtedly increases the possibility of cross-infections. In this article, based on our previous fabricated soft manipulator (Cell Reports Physical Science, 2021, 2, 100600), we performed the COVID-19 sampling on real human volunteers by exploiting a pre-programmed unmanned system. The unmanned sampling system mainly includes a soft manipulator and a rigid motion platform, which are adjusted by pneumatic control box and the motor control modules, respectively. Drawn on the lead-through teaching method, the unmanned sampling of COVID-19 is realized by recording the applied pressure in soft manipulator and the feed motion of rigid platform. This research provides a potential approach for unmanned COVID-19 sampling, solving the risk of cross-infection during manual collection.

19.
Sci Rep ; 13(1): 17803, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853132

RESUMO

Increasing evidences demonstrate that chlorogenic acid (CGA), a polyphenol with multiple effects such as anti-inflammatory and anti-oxidation, protects against myocardial ischemia-reperfusion injury (MIRI) in vitro and in vivo. But its detailed cardiac protection mechanism is still unclear. The MIRI mice model was established by ligating the left anterior descending branch (LAD) of the left coronary artery in C57BL/6 mice. Sixty C57BL/6 mice were randomly divided into four groups. CGA group and CGA + I/R group (each group n = 15) were gavaged with 30 mg/kg/day CGA for 4 weeks. Sham group and I/R group mice (each group n = 15) were administered equal volumes of saline. In vitro MIRI model was constructed by hypoxia and reoxygenation of HL-1 cardiomyocytes. The results showed that CGA pretreatment reduced myocardial infarction size and cTnT contents in serum, simultaneously reduced the levels of Lnc Neat1 expression and attenuated NLRP3 inflammasome-mediated pyroptosis in myocardial tissue. Consistent with in vivo results, the pretreatment of 0.2 µM and 2 µM CGA for 12 h in HL-1 cardiomyocytes depressed hypoxia/reoxygenation-induced Lnc Neat1 expression, NLRP3 inflammasome activation and pyroptosis. Lnc Neat1 shRNA transfection mediated by lentivirus in HL-1 cardiomyocytes significantly reduced activation of NLRP3 inflammasome and pyroptosis. Our findings suggest that CGA protects against MIRI by depressing Lnc Neat1 expression and NLRP3 inflammasome-mediated pyrotosis. Inhibiting the levels of Lnc Neat1 expression may be a therapeutic strategy for MIRI.


Assuntos
Inflamassomos , Traumatismo por Reperfusão Miocárdica , Camundongos , Animais , Inflamassomos/metabolismo , Piroptose , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/metabolismo , Ácido Clorogênico/farmacologia , Ácido Clorogênico/uso terapêutico , Camundongos Endogâmicos C57BL , Hipóxia
20.
Front Pharmacol ; 13: 950651, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935842

RESUMO

Duchenne muscular dystrophy (DMD) is a severe, progressive, and incurable X-linked disorder caused by mutations in the dystrophin gene. Patients with DMD have an absence of functional dystrophin protein, which results in chronic damage of muscle fibers during contraction, thus leading to deterioration of muscle quality and loss of muscle mass over time. Although there is currently no cure for DMD, improvements in treatment care and management could delay disease progression and improve quality of life, thereby prolonging life expectancy for these patients. Furthermore, active research efforts are ongoing to develop therapeutic strategies that target dystrophin deficiency, such as gene replacement therapies, exon skipping, and readthrough therapy, as well as strategies that target secondary pathology of DMD, such as novel anti-inflammatory compounds, myostatin inhibitors, and cardioprotective compounds. Furthermore, longitudinal modeling approaches have been used to characterize the progression of MRI and functional endpoints for predictive purposes to inform Go/No Go decisions in drug development. This review showcases approved drugs or drug candidates along their development paths and also provides information on primary endpoints and enrollment size of Ph2/3 and Ph3 trials in the DMD space.

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