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1.
Proc Natl Acad Sci U S A ; 121(33): e2405644121, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39121163

RESUMEN

Nuclear factor kappa B (NFκB) is a pathogenic factor in chronic lymphocytic leukemia (CLL) that is not addressed specifically by current therapies. NFκB is activated by inflammatory factors that stimulate toll-like receptors (TLRs) and receptors for interleukin-1 (IL-1) family members. IL-1 is considered a master regulator of inflammation, and IL-1 receptor signaling is inhibited by the IL-1 receptor antagonist anakinra. These considerations suggested that anakinra might have a role in the treatment of CLL. Consistent with this idea, anakinra inhibited spontaneous and TLR7-mediated activation of the canonical NFκB pathway in CLL cells in vitro. However, CLL cells exhibited only weak signaling responses to IL-1 itself, and anakinra was found to inhibit NFκB along with oxidative stress in an IL-1 receptor-independent manner. Anakinra was then administered with minimal toxicity to 11 previously untreated CLL patients in a phase I dose-escalation trial (NCT04691765). A stereotyped clinical response was observed in all patients. Anakinra lowered blood lymphocytes and lymph node sizes within the first month that were associated with downregulation of NFκB and oxidative stress in the leukemia cells. However, inhibition of NFκB was accompanied by upregulation of type 1 interferon (IFN) signaling, c-MYC-regulated genes and proteins, and loss of the initial clinical response. Anakinra increased IFN signaling and survival of CLL cells in vitro that were, respectively, phenocopied by mitochondrial antioxidants and reversed by IFN receptor blocking antibodies. These observations suggest that anakinra has activity in CLL and may be a useful adjunct for conventional therapies as long as compensatory IFN signaling is blocked at the same time.


Asunto(s)
Proteína Antagonista del Receptor de Interleucina 1 , Leucemia Linfocítica Crónica de Células B , FN-kappa B , Transducción de Señal , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/metabolismo , Humanos , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína Antagonista del Receptor de Interleucina 1/farmacología , Proteína Antagonista del Receptor de Interleucina 1/uso terapéutico , Receptores de Interleucina-1/metabolismo , Receptores de Interleucina-1/antagonistas & inhibidores , Masculino , Interferones/metabolismo , Femenino , Persona de Mediana Edad , Anciano , Estrés Oxidativo/efectos de los fármacos , Receptor Toll-Like 7/metabolismo , Receptor Toll-Like 7/antagonistas & inhibidores
3.
Chem Biodivers ; 20(7): e202300615, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37256824

RESUMEN

In recent years, numerous studies have reported on the anti-tumor properties of artemisinin and its derivatives. However, the relationship between their artemisinin chirality and activity remains unknown. In this study, we synthesized a series of artemisinin dimer derivatives with three different chiral structures and tested their antiproliferative activity in MCF-7 and HepG2 cells using the CCK-8 assay. Interestingly, we discovered that artemisinin dimer derivatives with ß, ß and α, ß conformations at C-10 exhibited stronger anti-tumor activity than those with an α, α configuration in MCF-7 and HepG2 cells. Notably, compound 4 showed an activity of 0.06 µM in MCF-7 cells. This study demonstrates the relationship between the conformation and activity of artemisinin dimer derivatives, and these derivatives have the potential to be developed into anti-cancer drugs.


Asunto(s)
Antimaláricos , Antineoplásicos , Artemisininas , Humanos , Artemisininas/farmacología , Artemisininas/química , Antineoplásicos/química , Antimaláricos/farmacología , Isomerismo , Ensayos de Selección de Medicamentos Antitumorales , Relación Estructura-Actividad , Proliferación Celular , Estructura Molecular
4.
J Environ Manage ; 342: 118232, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37270980

RESUMEN

Artificial neural networks exhibit significant advantages in terms of learning capability and generalizability, and have been increasingly applied in water quality prediction. Through learning a compressed representation of the input data, the Encoder-Decoder (ED) structure not only could remove noise and redundancies, but also could efficiently capture the complex nonlinear relationships of meteorological and water quality factors. The novelty of this study lies in proposing a multi-output Temporal Convolutional Network based ED model (TCN-ED) to make ammonia nitrogen forecasts for the first time. The contribution of our study is indebted to systematically assessing the significance of combining the ED structure with advanced neural networks for making accurate and reliable water quality forecasts. The water quality gauge station located at Haihong village of an island in Shanghai City of China constituted the case study. The model input contained one hourly water quality factor and hourly meteorological factors of 32 observed stations, where each factor was traced back to the previous 24 h and each meteorological factor of 32 gauge stations was aggregated into one areal average factor. A total of 13,128 hourly water quality and meteorological data were divided into two datasets corresponding to model training and testing stages. The Long Short-Term Memory based ED (LSTM-ED), LSTM and TCN models were constructed for comparison purposes. The results demonstrated that the developed TCN-ED model can succeed in mimicking the complex dependence between ammonia nitrogen and water quality and meteorological factors, and provide more accurate ammonia nitrogen forecasts (1- up to 6-h-ahead) than the LSTM-ED, LSTM and TCN models. The TCN-ED model, in general, achieved higher accuracy, stability and reliability compared with the other models. Consequently, the improvement can facilitate river water quality forecasting and early warning, as well as benefit water pollution prevention in the interest of river environmental restoration and sustainability.


Asunto(s)
Amoníaco , Monitoreo del Ambiente , Monitoreo del Ambiente/métodos , China , Reproducibilidad de los Resultados , Modelos Teóricos , Nitrógeno/análisis , Predicción
5.
Circulation ; 144(1): 34-51, 2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-33821668

RESUMEN

BACKGROUND: Cardiac hypertrophy is an independent risk factor for heart failure, a leading cause of morbidity and mortality globally. The calcineurin/NFAT (nuclear factor of activated T cells) pathway and the MAPK (mitogen-activated protein kinase)/Erk (extracellular signal-regulated kinase) pathway contribute to the pathogenesis of cardiac hypertrophy as an interdependent network of signaling cascades. How these pathways interact remains unclear and few direct targets responsible for the prohypertrophic role of NFAT have been described. METHODS: By engineering cardiomyocyte-specific ETS2 (a member of the E26 transformation-specific sequence [ETS] domain family) knockout mice, we investigated the role of ETS2 in cardiac hypertrophy. Primary cardiomyocytes were used to evaluate ETS2 function in cell growth. RESULTS: ETS2 is phosphorylated and activated by Erk1/2 on hypertrophic stimulation in both mouse (n=3) and human heart samples (n=8 to 19). Conditional deletion of ETS2 in mouse cardiomyocytes protects against pressure overload-induced cardiac hypertrophy (n=6 to 11). Silencing of ETS2 in the hearts of calcineurin transgenic mice significantly attenuates hypertrophic growth and contractile dysfunction (n=8). As a transcription factor, ETS2 is capable of binding to the promoters of hypertrophic marker genes, such as ANP, BNP, and Rcan1.4 (n=4). We report that ETS2 forms a complex with NFAT to stimulate transcriptional activity through increased NFAT binding to the promoters of at least 2 hypertrophy-stimulated genes: Rcan1.4 and microRNA-223 (=n4 to 6). Suppression of microRNA-223 in cardiomyocytes inhibits calcineurin-mediated cardiac hypertrophy (n=6), revealing microRNA-223 as a novel prohypertrophic target of the calcineurin/NFAT and Erk1/2-ETS2 pathways. CONCLUSIONS: Our findings point to a critical role for ETS2 in calcineurin/NFAT pathway-driven cardiac hypertrophy and unveil a previously unknown molecular connection between the Erk1/2 activation of ETS2 and expression of NFAT/ETS2 target genes.


Asunto(s)
Calcineurina/metabolismo , Cardiomegalia/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Factores de Transcripción NFATC/metabolismo , Proteína Proto-Oncogénica c-ets-2/metabolismo , Animales , Calcineurina/genética , Cardiomegalia/genética , Cardiomegalia/patología , Células Cultivadas , Células HEK293 , Humanos , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Factores de Transcripción NFATC/genética , Unión Proteica/fisiología , Proteína Proto-Oncogénica c-ets-2/genética , Ratas , Ratas Sprague-Dawley
6.
Cell Mol Biol (Noisy-le-grand) ; 68(7): 123-128, 2022 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-36495508

RESUMEN

Vascular calcification is one of the major complications of chronic kidney disease (CKD), which could be further accelerated by the osteogenic transition and apoptosis of smooth muscle cells, thereby advancing the progression of renal diseases and increasing the mortality rate of cardiovascular events. MicroRNA is a kind of key regulator in the phenotypic transition of vascular smooth muscle cells (VSMCs), but its role remains unclear in VSMCs. In this study, VSMCs were stimulated by platelet-derived growth factors - BB (PDGF-BB) in varying concentrations to establish the VSMC dysfunction models. The relative expression of miR-29a-5p was quantified via the quantitative real-time polymerase chain reaction (qRT-PCR). The proliferation of VSMCs was determined via the BrdU method, analysis of cell cycle via flow cytometry, and the migration of VSMCs via Transwell assay. Expression of γ-secretase activating protein (GSAP) and markers of VSMC differentiation, including α-SMA, SM-22α, SMMHC and Calponin, was quantified via the Western blot. The targeting relationship between the 3'-UTR of miR-29a-5p and GSAP was validated through the dual-luciferase reporter gene assay. As a result, we found that PDGF-BB could trigger a decrease of miR-29a-5p in a time- and dose-dependent manner (P < 0.05). Overexpression of miR-29a-5p could curb the effect of PDGF-BB on the proliferation and migration of VSMCs while upregulating the expression of markers of differentiation (P < 0.05). In addition, the expression of GSAP was also affected by the negative regulation of miR-29a-5p, while the restoration of GSAP eliminated the effect of miR-29a-5p on the VSMCs partially (P < 0.05). Moreover, vascular calcification models were also established in the CKD rats, suggesting that the inhibition of GSAP could prevent PTH-induced vascular calcification in CKD rats. In conclusion, miR-29a-5p could inhibit the PDGF-BB-induced proliferation, migration and phenotypic transition of VSMCs via targeting GSAP. Thus, miR-29a-5p/GSAP might be a potential target for the treatment of vascular calcification.


Asunto(s)
MicroARNs , Insuficiencia Renal Crónica , Calcificación Vascular , Ratas , Animales , Músculo Liso Vascular , Becaplermina/genética , Becaplermina/metabolismo , Becaplermina/farmacología , Proliferación Celular , Movimiento Celular/genética , Miocitos del Músculo Liso/metabolismo , MicroARNs/metabolismo , Regiones no Traducidas 3' , Ciclo Celular , Calcificación Vascular/genética , Calcificación Vascular/metabolismo , Insuficiencia Renal Crónica/genética , Insuficiencia Renal Crónica/metabolismo , Células Cultivadas
7.
BMC Musculoskelet Disord ; 23(1): 917, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36242023

RESUMEN

BACKGROUND: Lower back pain and stiffness are the typical symptoms of ankylosing spondylitis (AS). In this study, muscle mass was assessed by muscle density, mechanical elasticity, and area. We investigated the characteristics of lumbar paraspinal-muscle (PSM) mass using muscle ultrasound shear-wave elastography (SWE), as well as the validity of this method for identifying patients with AS. METHODS: We recruited a representative cohort of 30 AS patients, and 27 healthy volunteers who were age- and sex-matched to the patient study group, investigated the Young's modulus (YM), cross-sectional area (CSA) and thickness of lumbar multifidus (LM) muscle using SWE. This study did not need to be randomized. Data were collected at the department of ultrasonography of Guangdong Provincial Hospital of Chinese Medicine. We analyzed the data using SPSS version 18.0 (IBM Corp, Armonk, NY, USA). Normal distribution was evaluated by the Shapiro-Wilk test and Q-Q plots. Demographic and baseline data will be analyzed with standard descriptive statistics. Data will be presented as the mean ± standard deviation (SD). Non-normally distributed data are presented as medians with interquartile ranges (IQR). RESULTS: Young's modulus (YM) of SWE in AS patients was significantly higher than that in volunteers. Percentage change in lumbar multifidus (LM) muscle cross-sectional area (CSA) and thickness were significantly lower in AS patients than in healthy volunteers on the left side of the body. Correlation analysis showed a positive correlation between percentage change in CSA and thickness in both volunteers and AS patients. In AS patients, YM was negatively correlated with percentage change of CSA and thickness on the right side, while increased disease duration in AS was associated with increased YM on the left. CONCLUSION: AS patients showed reductions in LM muscle mass and function as the disease progressed, SWE could reflect these changes well. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2000031476. Registered 02/04/2020. http://www.chictr.org.cn/index.aspx .


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Espondilitis Anquilosante , Módulo de Elasticidad , Diagnóstico por Imagen de Elasticidad/métodos , Humanos , Región Lumbosacra/diagnóstico por imagen , Músculos Paraespinales/diagnóstico por imagen , Músculos Paraespinales/fisiología , Espondilitis Anquilosante/diagnóstico por imagen
8.
J Appl Clin Med Phys ; 23(7): e13612, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35635800

RESUMEN

PURPOSE: We explored the effects of geometrical topological properties of tumors such as tumor length and "axial cross-sectional area (ACSA)" of tumors (planning target volume [PTV] volume /PTV length) on the dosimetric parameters of organs at risk (lung and heart) in patients with esophagus cancer (EPC) treated by way of intensity-modulated radiation therapy (IMRT), so as to provide a guideline for the dosimetric limitation for organs at risk in IMRT treatment. METHODS: A retrospective analysis was done on 103 cases of patients with EPC who were treated by IMRT from November 2010 to August 2019, in which PTV-G stood for the externally expanded planning target volume (PTV) of the gross tumor volume (GTV) and PTV-C for the externally expanded volume of the clinical target volume (CTV). A linear regression model was employed to analyze the several pairs of correlation: the 1st one between the relative length of tumors (PTV length/lung length) and pulmonary dose-volume parameters, the 2nd one between ACSA of tumors and pulmonary dose-volume parameters, the 3rd one between PTV length and the dosimetric parameters of the heart, and the last one between ACSA of tumors and the dosimetric parameters of the heart. RESULTS: (i) There was a strong positive correlation between the relative length of tumors (PTV length/lung length) and V5 (p < 0.001, r = 0.73), and V10 (p < 0.001, r = 0.66) of the lung. There was a moderate positive correlation between the relative length of tumors and V30 (p < 0.001, r = 0.44) of the lung, and a weak positive correlation between the relative length of tumors and V20 (p < 0.001, r = 0.39) of the lung. (ii) There was a strong positive correlation between ACSA of tumors (PTV volume/PTV length) and V30 (p < 0.001, r = 0.67) of the lung, a moderate positive correlation between ACSA of tumors and V20 (p <0.001, r = 0.51) of the lung, and a weak positive correlation between ACSA of tumors and V10 (p = 0.019, r = 0.23) of the lung, yet there was not an obvious correlation between ACSA of tumors and V5 p > 0.05) of the lung. (iii) There was a moderate positive correlation between PTV length and V40 (p < 0.001, r = 0.58), and Dmean (p < 0.001, r = 0.52) of the heart, yet there was no obvious correlation between ACSA of tumors and Dmean and V40 of the heart (p > 0.05). CONCLUSIONS: (i) Compared with the high-dose region of the lung, the relative length of tumors (PTV length/lung length) has a greater impact on the low-dose region of the lung. The linear regression equation of scatter plot showed that when the relative length of tumors increased by 0.1, the lung dose-volume parameters of V5 , V10 , V20 , and V30 increased by approximately 5.37%, 3.59%, 1.05%, and 1.08%, respectively. When PTV length increased by 1 cm, Dmean and V40 of the heart increased by approximately 153.6 cGy and 2.03%, respectively. (ii) Compared with the low-dose region of the lung, the value of ACSA of tumors (PTV volume/PTV length) has a greater impact on the high-dose region of the lung. However, the value of ACSA of tumors has no significant effect on the dosimetric parameters of the heart (Dmean and V40 ). The linear regression equation of scatter plot showed that when ACSA of tumors increased by 10 cm2 , the lung dose-volume parameters of V10 , V20, and V30 increased by approximately 3.11%, 3.37%, and 4.01%, respectively.


Asunto(s)
Neoplasias Esofágicas , Radioterapia de Intensidad Modulada , Neoplasias Esofágicas/radioterapia , Humanos , Órganos en Riesgo/efectos de la radiación , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Estudios Retrospectivos
9.
J Neuroinflammation ; 17(1): 310, 2020 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-33070779

RESUMEN

BACKGROUND: The major dose-limiting toxicity of paclitaxel, one of the most commonly used drugs to treat solid tumor, is painful neuropathy. However, the molecular mechanisms underlying paclitaxel-induced painful neuropathy are largely unclarified. METHODS: Paw withdrawal threshold was measured in the rats following intraperitoneal injection of paclitaxel. The qPCR, western blotting, protein or chromatin immunoprecipitation, ChIP-seq identification of NFATc2 binding sites, and microarray analysis were performed to explore the molecular mechanism. RESULTS: We found that paclitaxel treatment increased the nuclear expression of NFATc2 in the spinal dorsal horn, and knockdown of NFATc2 with NFATc2 siRNA significantly attenuated the mechanical allodynia induced by paclitaxel. Further binding site analysis utilizing ChIP-seq assay combining with gene expression profile revealed a shift of NFATc2 binding site closer to TTS of target genes in dorsal horn after paclitaxel treatment. We further found that NFATc2 occupancy may directly upregulate the chemokine CXCL14 expression in dorsal horn, which was mediated by enhanced interaction between NFATc2 and p300 and consequently increased acetylation of histone H4 in CXCL14 promoter region. Also, knockdown of CXCL14 in dorsal horn significantly attenuated mechanical allodynia induced by paclitaxel. CONCLUSION: These results suggested that enhanced interaction between p300 and NFATc2 mediated the epigenetic upregulation of CXCL14 in the spinal dorsal horn, which contributed to the chemotherapeutic paclitaxel-induced chronic pain.


Asunto(s)
Quimiocinas CXC/biosíntesis , Epigénesis Genética/efectos de los fármacos , Factores de Transcripción NFATC/biosíntesis , Neuralgia/inducido químicamente , Neuralgia/metabolismo , Paclitaxel/toxicidad , Animales , Antineoplásicos Fitogénicos/toxicidad , Secuencia de Bases , Quimiocinas CXC/genética , Epigénesis Genética/fisiología , Masculino , Factores de Transcripción NFATC/genética , Neuralgia/genética , Unión Proteica/fisiología , Ratas , Ratas Sprague-Dawley , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/fisiología
10.
Mol Cell Probes ; 50: 101500, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31887421

RESUMEN

OBJECTIVE: To investigate the effect of lncRNA XIST on apoptosis induced by hypoxia. METHODS: We analyzed the expression levels of lncRNA XIST and miR-122-5p using RT-qPCR in hypoxia-induced cardiomyocytes. The mechanism by which lncRNA XIST affects myocardial ischemia was investigated using the cell transfection, CCK-8, and dual-luciferase reporter assays, as well as by flowcytometry, western blotting, and RNA immunoprecipitation. RESULTS: Hypoxic H9c2 cells demonstrated a decrease in their migration and invasion abilities and XIST expression and an increase in the extent of their apoptosis and expression of microRNA-122-5p. Overexpression of XIST significantly increased the H9c2 cell viability, enhanced cell migration and invasion, and decreased cell apoptosis in a hypoxic environment. The luciferase activity of XIST-WT in H9c2 cells co-transfected with XIST-WT and microRNA-122-5p mimics had decreased. The results of RNA immunoprecipitation showed that XIST interacted directly with miRNA-122-5p. Overexpression of XIST decreased the level of miRNA-122-5p significantly. mi-122-5p mimics increased H9c2 cell apoptosis and downregulated FOXP2 expression. Overexpression of FOXP2 upregulated the expression of the Bcl-2 protein in H9c2 cells transfected with microRNA-122-5p mimics and inhibited the expression of HIF-alpha, Bax, and the cleaved-caspase 9 protein. CONCLUSION: lncRNA XIST could regulate the miR-122-5p/FOXP2 axis to attenuate hypoxia-induced H9c2 cardiomyocyte injury.


Asunto(s)
Factores de Transcripción Forkhead/metabolismo , MicroARNs/metabolismo , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , ARN Largo no Codificante/metabolismo , Animales , Secuencia de Bases , Hipoxia de la Célula/genética , Línea Celular , Regulación hacia Abajo/genética , Factores de Transcripción Forkhead/genética , MicroARNs/genética , Plásmidos/metabolismo , ARN Largo no Codificante/genética , Ratas , Transducción de Señal
12.
Clin Lab ; 64(11)2018 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-30549999

RESUMEN

BACKGROUND: X-linked thrombocytopenia (XLT) is a milder form of Wiskott-Aldrich syndrome (WAS), characterized predominantly by thrombocytopenia with small-sized platelets. Mutations in the WAS gene are responsible for the disease. We herein detected a new mutation in the WAS gene responsible for XLT in a 3-generation Chinese pedigree. METHODS: Peripheral blood samples were collected from 7 members in the family. WAS gene was amplified from genomic DNA isolated from leucocytes, and then direct sequencing was performed. RESULTS: Three male members of this family (the proband, his younger brother and maternal uncle) had thrombocytopenia and decreased mean platelet volume. A homozygous mutation (T>C) was found at nucleotide position 319 in exon 3, causing the amino acid Tyr (T) to be abnormally changed to His (H) at position 107. Two female members (the proband's mother and grandmother) were carriers of the mutation. CONCLUSIONS: XLT is easy to misdiagnose as immune thrombocytopenic purpura (ITP). The diagnosis of XLT should be considered in any male with congenital microthrombocytopenia or early onset of microthrombocytope-nia (< 7 fL). This article adds to the growing number of known mutations associated with XLT.


Asunto(s)
Enfermedades Genéticas Ligadas al Cromosoma X/genética , Mutación Missense , Trombocitopenia/genética , Proteína del Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/genética , Adolescente , Pueblo Asiatico/genética , Secuencia de Bases , China , Análisis Mutacional de ADN , Exones/genética , Femenino , Enfermedades Genéticas Ligadas al Cromosoma X/sangre , Enfermedades Genéticas Ligadas al Cromosoma X/etnología , Humanos , Masculino , Volúmen Plaquetario Medio , Linaje , Trombocitopenia/sangre , Trombocitopenia/etnología , Síndrome de Wiskott-Aldrich/sangre , Síndrome de Wiskott-Aldrich/etnología
13.
Eur Heart J ; 38(18): 1389-1398, 2017 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-27099261

RESUMEN

AIMS: Oxidative stress contributes to the development of cardiac hypertrophy and heart failure. One of the mitochondrial sirtuins, Sirt4, is highly expressed in the heart, but its function remains unknown. The aim of the present study was to investigate the role of Sirt4 in the pathogenesis of pathological cardiac hypertrophy and the molecular mechanism by which Sirt4 regulates mitochondrial oxidative stress. METHODS AND RESULTS: Male C57BL/6 Sirt4 knockout mice, transgenic (Tg) mice exhibiting cardiac-specific overexpression of Sirt4 (Sirt4-Tg) and their respective controls were treated with angiotensin II (Ang II, 1.1 mg/kg/day). At 4 weeks, hypertrophic growth of cardiomyocytes, fibrosis and cardiac function were analysed. Sirt4 deficiency conferred resistance to Ang II infusion by significantly suppressing hypertrophic growth, and the deposition of fibrosis. In Sirt4-Tg mice, aggravated hypertrophy and reduced cardiac function were observed compared with non-Tg mice following Ang II treatment. Mechanistically, Sirt4 inhibited the binding of manganese superoxide dismutase (MnSOD) to Sirt3, another member of the mitochondrial sirtuins, and increased MnSOD acetylation levels to reduce its activity, resulting in elevated reactive oxygen species (ROS) accumulation upon Ang II stimulation. Furthermore, inhibition of ROS with manganese 5, 10, 15, 20-tetrakis-(4-benzoic acid) porphyrin, a mimetic of SOD, blocked the Sirt4-mediated aggravation of the hypertrophic response in Ang II-treated Sirt4-Tg mice. CONCLUSIONS: Sirt4 promotes hypertrophic growth, the generation of fibrosis and cardiac dysfunction by increasing ROS levels upon pathological stimulation. These findings reveal a role of Sirt4 in pathological cardiac hypertrophy, providing a new potential therapeutic strategy for this disease.


Asunto(s)
Cardiomegalia/enzimología , Proteínas Mitocondriales/fisiología , Sirtuinas/fisiología , Superóxido Dismutasa/antagonistas & inhibidores , Angiotensina II/farmacología , Animales , Técnicas de Silenciamiento del Gen , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mitocondrias Cardíacas/enzimología , Miocitos Cardíacos/enzimología , Estrés Oxidativo/fisiología , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Remodelación Vascular/fisiología , Vasoconstrictores/farmacología
14.
Artículo en Inglés | MEDLINE | ID: mdl-39110566

RESUMEN

Body Channel Communication (BCC) utilizes the body surface as a low-loss signal transmission medium, reducing the power consumption of wireless wearable devices. However, the effective communication range on the human body is limited in the state-of-the-art BCC transceivers, where the signal loss between the body surface and the BCC receiver remains one of the main bottlenecks. To reduce the interface loss, a high input impedance is desired by the BCC receiver, but the DC-biasing circuits decrease the input impedance. In this work, a dynamically-sampling IFE is proposed to eliminate the DC voltage bias, resulting in a 90kΩ high input impedance and a 94dB RF-IF conversion gain to reduce the interface loss in long-range BCC applications. The BCC transceiver chip is fabricated in 55nm CMOS process, taking a die area of 0.123mm2. Measured results show that the chip extends the BCC range to 2m for both the forward and backward paths, where the transmitter and receiver consume 711µW power in total.

15.
Insect Sci ; 2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38643372

RESUMEN

The gut microbiome is a key partner of animals, influencing various aspects of their physiology and behaviors. Among the diverse behaviors regulated by the gut microbiome, locomotion is vital for survival and reproduction, although the underlying mechanisms remain unclear. Here, we reveal that the gut microbiome modulates the locomotor behavior of Drosophila larvae via a specific neuronal type in the brain. The crawling speed of germ-free (GF) larvae was significantly reduced compared to the conventionally reared larvae, while feeding and excretion behaviors were unaffected. Recolonization with Acetobacter and Lactobacillus can fully and partially rescue the locomotor defects in GF larvae, respectively, probably due to the highest abundance of Acetobacter as a symbiotic bacterium in the larval gut, followed by Lactobacillus. Moreover, the gut microbiome promoted larval locomotion, not by nutrition, but rather by enhancing the brain levels of tyrosine decarboxylase 2 (Tdc2), which is an enzyme that synthesizes octopamine (OA). Overexpression of Tdc2 rescued locomotion ability in GF larvae. These findings together demonstrate that the gut microbiome specifically modulates larval locomotor behavior through the OA signaling pathway, revealing a new mechanism underlying larval locomotion regulated by the gut microbiome.

16.
Artículo en Inglés | MEDLINE | ID: mdl-38896527

RESUMEN

Miniaturization of wireless neural-recording systems enables minimally-invasive surgery and alleviates the rejection reactions for implanted brain-computer interface (BCI) applications. Simultaneous massive-channel recording capability is essential to investigate the behaviors and inter-connections in billions of neurons. In recent years, battery-free techniques based on wireless power transfer (WPT) and backscatter communication have reduced the sizes of neural-recording implants by battery eliminating and antenna sharing. However, the existing battery-free chips realize the multi-channel merging in the signal-acquisition circuits, which leads to large chip area, signal attenuation, insufficient channel number or low bandwidth, etc. In this work, we demonstrate a 2mm×2mm battery-free neural dielet, which merges 128 channels in the wireless part. The neural dielet is fabricated with 65nm CMOS process, and measured results show that: 1) The proposed multi-carrier orthogonal backscatter technique achieves a high data rate of 20.16Mb/s and an energy efficiency of 0.8pJ/bit. 2) A self-calibrated direct digital converter (SC-DDC) is proposed to fit the 128 channels in the 2mm×2mm die, and then the all-digital implementation achieves 0.02mm2 area and 9.87µW power per channel.

17.
Micromachines (Basel) ; 15(7)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-39064365

RESUMEN

The cutting of thick glass is extensively employed in aerospace, optical, and other fields. Although ultrafast laser Bessel beams are heavily used for glass cutting, the cutting thickness and cutting quality need to be further improved. In this research, the high-quality cutting of thick glass was realized for the first time using ultrafast laser perforation assisted by CO2 laser separation. Initially, an infrared picosecond laser Bessel beam was employed to ablate the soda-lime glass and generate a perforated structure. Subsequently, a CO2 laser was employed to induce crack propagation along the path of the perforated structure, resulting in the separation of the glass. This study investigates the influence of hole spacing, pulse energy, and the defocusing distance of the picosecond laser Bessel beam on the average surface roughness of the glass sample cutting surface. The optimal combination of cutting parameters for 6 mm thick glass results in a minimum surface roughness of 343 nm in the cross-section.

18.
Sci Total Environ ; 912: 168742, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38007130

RESUMEN

Microplastics are widely used due to their numerous advantages. However, they can have detrimental effects on marine ecosystems. When microplastics enter the ocean, they can be absorbed by marine organisms, leading to toxic effects. Additionally, the transformation of microplastics during natural degradation can alter their toxicity, necessitating further investigation. Polylactic acid (PLA) biodegradable plastics are commonly used, yet research on their toxicity, particularly their reproductive effects on aquatic organisms, remains limited. In this study, we conducted photodegradation of PLA using potassium persulfate as a catalyst to simulate natural degradation conditions. Our objective was to assess the reproductive toxicity of photodegraded PLA microplastics on zebrafish. The results revealed that photodegraded PLA exhibited elevated reproductive toxicity, resulting in abnormal oocyte differentiation, disruption of sexual hormone levels, and alterations in ovarian tissue metabolism. Metabolomics analysis indicated that both unphotodegraded PLA (UPLA) and photodegraded PLA (DPLA) disrupted oxidative stress homeostasis in zebrafish ovarian tissue by influencing pathways such as purine metabolism, phenylalanine metabolism, glutathione metabolism, and riboflavin metabolism. Furthermore, the DPLA treatment induced abnormal biosynthesis of taurocholic acid, which was not observed in the UPLA treatment group. Importantly, the DPLA treatment group exhibited more pronounced effects on offspring development compared to the UPLA treatment group, characterized by higher mortality rates, inhibition of embryo hatching, accelerated heart rates, and reduced larval body length. These findings underscore the varying levels of toxicity to zebrafish ovaries before and after PLA photodegradation, along with evidence of intergenerational toxicity.


Asunto(s)
Plásticos Biodegradables , Contaminantes Químicos del Agua , Animales , Microplásticos , Plásticos , Pez Cebra , Ecosistema , Poliésteres , Organismos Acuáticos , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis
19.
IEEE Trans Biomed Circuits Syst ; 18(1): 39-50, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37549076

RESUMEN

Wireless implantable devices are widely used in medical treatment, which should meet clinical constraints such as longevity, miniaturization, and reliable communication. Wireless power transfer (WPT) can eliminate the battery to reduce system size and prolong device life, while it's challenging to generate a reliable clock without a crystal. In this work, we propose a self-adaptive dual-injection-locked-ring-oscillator (dual-ILRO) clock-recovery technique based on two-tone WPT and integrate it into a battery-free neural-recording SoC. The 2[Formula: see text]-order inter-modulation (IM2) component of the two WPT tones is extracted as a low-frequency reference for battery-free SoC, and the proposed self-adaptive dual-ILRO technique extends the lock range to ensure an anti-interference PVT-robust clock generation. The neural-recording SoC includes a low-noise signal acquisition unit, a power management unit, and a backscatter circuit to perform neural signal recording, wireless power harvesting, and neural data transmission. Benefiting from the 6.4 µW low power of the clock recovery circuit, the overall SoC power is cut down to 49.8 µW. In addition, the proposed clock-recovery technique enables both signal acquisition and uplink communication to perform as well as that synchronized by an ideal clock, i.e., an effective number of 9.6 bits and a bit error rate (BER) less than 4.8 × 10-7 in chip measurement. The SoC takes a die area of 2.05 mm 2, and an animal test is conducted in a Sprague-Dawley rat to validate the wireless neural-recording performance, compared to a crystal-synchronized commercial chip.


Asunto(s)
Prótesis e Implantes , Tecnología Inalámbrica , Ratas , Animales , Ratas Sprague-Dawley , Diseño de Equipo , Suministros de Energía Eléctrica
20.
Acta Pharm Sin B ; 14(2): 712-728, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38322347

RESUMEN

Coronary restenosis is an important cause of poor long-term prognosis in patients with coronary heart disease. Here, we show that lysine methyltransferase SMYD2 expression in the nucleus is significantly elevated in serum- and PDGF-BB-induced vascular smooth muscle cells (VSMCs), and in tissues of carotid artery injury-induced neointimal hyperplasia. Smyd2 overexpression in VSMCs (Smyd2-vTg) facilitates, but treatment with its specific inhibitor LLY-507 or SMYD2 knockdown significantly inhibits VSMC phenotypic switching and carotid artery injury-induced neointima formation in mice. Transcriptome sequencing revealed that SMYD2 knockdown represses the expression of serum response factor (SRF) target genes and that SRF overexpression largely reverses the inhibitory effect of SMYD2 knockdown on VSMC proliferation. HDAC3 directly interacts with and deacetylates SRF, which enhances SRF transcriptional activity in VSMCs. Moreover, SMYD2 promotes HDAC3 expression via tri-methylation of H3K36 at its promoter. RGFP966, a specific inhibitor of HDAC3, not only counteracts the pro-proliferation effect of SMYD2 overexpression on VSMCs, but also inhibits carotid artery injury-induced neointima formation in mice. HDAC3 partially abolishes the inhibitory effect of SMYD2 knockdown on VSMC proliferation in a deacetylase activity-dependent manner. Our results reveal that the SMYD2-HDAC3-SRF axis constitutes a novel and critical epigenetic mechanism that regulates VSMC phenotypic switching and neointimal hyperplasia.

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