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1.
ACS Nano ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38885193

RESUMEN

Polaritons, hybrid light and matter waves, offer a platform for subwavelength on-chip light manipulation. Recent works on planar refraction and focusing of polaritons all rely on heterogeneous components with different refractive indices. A fundamental question, thus, arises whether it is possible to configure two-dimensional monolithic polariton lenses based on a single medium. Here, we design and fabricate a type of monolithic polariton lens by directly sculpting an individual hyperbolic van der Waals crystal. The in-plane polariton focusing through sculptured step-terraces is triggered by geometry-induced symmetry breaking of momentum matching in polariton refractions. We show that the monolithic polariton lenses can be robustly tuned by the rise of van der Waals terraces and their curvatures, achieving a subwavelength focusing resolution down to 10% of the free-space light wavelength. Fusing with transformation optics, monolithic polariton lenses with gradient effective refractive indices, such as Luneburg lenses and Maxwell's fisheye lenses, are expected by sculpting polaritonic structures with gradually varied depths. Our results bear potential in planar subwavelength lenses, integrated optical circuits, and photonic chips.

2.
Nano Lett ; 24(4): 1360-1366, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38252685

RESUMEN

Dielectric environment engineering is an efficient and general approach to manipulating polaritons. Liquids serving as the surrounding media of polaritons have been used to shift polariton dispersions and tailor polariton wavefronts. However, those liquid-based methods have so far been limited to their static states, not fully unleashing the promise offered by the mobility of liquids. Here, we propose a microfluidic strategy for polariton manipulation by merging polaritonics with microfluidics. The diffusion of fluids causes gradient refractive indices over microchannels, which breaks the symmetry of polariton dispersions and realizes the microfluidic analogue to nonreciprocal polariton dragging. Based on polariton microfluidics, we also designed a set of on-chip polaritonic elements to actively shape polaritons, including planar lenses, off-axis lenses, Janus lenses, bends, and splitters. Our strategy expands the toolkit for the manipulation of polaritons at the subwavelength scale and possesses potential in the fields of polariton biochemistry and molecular sensing.

3.
Front Cardiovasc Med ; 10: 1138705, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37187789

RESUMEN

Background: This review aims to summarize the antiapoptotic, pro-survival, and antifibrotic effects of exercise training in hypertensive hearts. Methods: Keyword searches were conducted in PubMed, Web of Science, and Scopus in May 2021. Research published in English on the effects of exercise training on the apoptosis, survival, and fibrosis pathways in hypertension was included. The CAMARADES checklist was used to determine the quality of the studies. Two reviewers independently implemented predesigned protocols for the search and selection of studies, the assessment of study quality, and the evaluation of the strength of evidence. Results: Eleven studies were included after selection. The duration of the exercise training ranged from 5 to 27 weeks. Nine studies showed that exercise training improved cardiac survival rates by increasing IGF-1, IGF-1 receptor, p-PI3K, Bcl-2, HSP 72, and p-Akt. Furthermore, 10 studies showed that exercise training reduced apoptotic pathways by downregulating Bid, t-Bid, Bad, Bak, Bax, TNF, and FADD. Finally, two studies reported the modification and subsequent improvement of physiological characteristics of fibrosis and decreased MAPK p38 and PTEN levels by exercise training in the left ventricle of the heart. Conclusions: The findings of the review showed that exercise training could improve cardiac survival rates and attenuate cardiac apoptotic and fibrotic pathways in hypertension, suggesting that exercise training could act as a therapeutic approach to prevent hypertension-induced cardiac apoptosis and fibrosis. Systematic Review Registration: https://www.crd.york.ac.uk, identifier: CRD42021254118.

4.
Front Psychol ; 13: 958938, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36337549

RESUMEN

Sleep quality, personality, and cognitive load potentially increase second language writing (SLW) anxiety and subsequently affect SLW achievement. This study investigates the predictions of sleep quality, personality (social inhibition/ negative affectivity), and cognitive load (content/ computer) toward SLW anxiety and achievement in a computer-based test. Participants included 172 voluntary undergraduates majoring in English as foreign language. SLW anxiety in a computer-based test, sleep disturbance, personality and cognitive load was assessed with the SLW Anxiety Inventory, Pittsburg Sleep Quality Index, Type-D Personality, and cognitive load questionnaires. A structural equation modeling approach was applied to examine the interdependence among the observed variables. An adequate-fit SLW anxiety model was built (X2 = 6.37, df = 6, p = 0.383, NFI = 0.97, CFI = 1.00, RMSEA = 0.02; R-squared multiple correlations: SLW anxiety in a computer-based test = 0.19, computer-based SLW achievement = 0.07). The structural model showed that sleep disturbance (+0.17), social inhibition personality (+0.31), and computer-induced cognitive load (+0.16) were significant predictors of SLW anxiety in a computer-based test. Subsequently, SLW anxiety in a computer-based test (-0.16) and computer-induced cognitive load (-0.16) were significant negative predictors of computer-based SLW achievement.

5.
Front Cardiovasc Med ; 9: 949744, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36304547

RESUMEN

Objective: Cardiac mitochondrial dysfunction was found in ischemic heart disease (IHD). Hence, this study determined the effects of exercise training (ET) on cardiac mitochondrial respiration and cardiac mitochondrial quality control in IHD. Methods: A narrative synthesis was conducted after searching animal studies written in English in three databases (PubMed, Web of Science, and EMBASE) until December 2020. Studies that used aerobic exercise as an intervention for at least 3 weeks and had at least normal, negative (sedentary IHD), and positive (exercise-trained IHD) groups were included. The CAMARADES checklist was used to check the quality of the included studies. Results: The 10 included studies (CAMARADES score: 6-7/10) used swimming or treadmill exercise for 3-8 weeks. Seven studies showed that ET ameliorated cardiac mitochondrial respiratory function as manifested by decreased reactive oxygen species (ROS) production and increased complexes I-V activity, superoxide dismutase 2 (SOD2), respiratory control ratio (RCR), NADH dehydrogenase subunits 1 and 6 (ND1/6), Cytochrome B (CytB), and adenosine triphosphate (ATP) production. Ten studies showed that ET improved cardiac mitochondrial quality control in IHD as manifested by enhanced and/or controlled mitochondrial biogenesis, dynamics, and mitophagy. Four other studies showed that ET resulted in better cardiac mitochondrial physiological characteristics. Conclusion: Exercise training could improve cardiac mitochondrial functions, including respiration, biogenesis, dynamics, and mitophagy in IHD. Systematic review registration: https://www.crd.york.ac.uk/prospero/ display_record.php?RecordID=226817, identifier: CRD42021226817.

6.
J Cardiovasc Dev Dis ; 9(8)2022 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-36005430

RESUMEN

BACKGROUND: The present study investigated whether angiotensin II type 1 receptor blocker irbesartan (ARB) and partial agonist of PPAR-γ prevents heart apoptosis by suppressing cardiac Fas/FasL-mediated to mitochondria-mediated apoptosis in the hearts of hypertensive rat model. METHODS: Cardiac function using echocardiography, H&E staining, TUNEL assay, and Western blotting were measured in the excised hearts from three groups, i.e., an untreated hypertensive group (SHR), an ARB-treated hypertensive group (50 mg/kg/day, S.C., SHR-ARB), and untreated normotensive Wistar-Kyoto rats (WKY). RESULTS: Fas Ligand, Fas death receptors, FADD, active caspase-8, active caspase-3 (Fas/FasL-mediated apoptotic pathway), as well as Bax, cytochrome c, active caspase-9 and -3 (mitochondria-mediated apoptotic pathway), IGF-II, and p-JNK were decreased in SHR-ARB group when compared with the SHR group. SIRT1, PGC-1α, Bcl2, and Bcl-xL (SIRT1/PGC-1α pro-survival pathway) were increased in the SHR-ARB group when compared with the SHR group. CONCLUSIONS: Our findings suggested that the ARB might prevent cardiac Fas/FasL-mediated to mitochondria-mediated apoptosis pathway in the hypertensive model associated with IGF-II, p-JNK deactivation, and SIRT1/PGC-1α pro-survival pathway upregulation. ARB prevents hypertension-enhanced cardiac apoptosis via enhancing SIRT1 longevity signaling and enhances the mitochondrial biogenetic survival pathway.

7.
Front Aging Neurosci ; 13: 705304, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34456710

RESUMEN

This study aimed to investigate cerebral cortex apoptosis on the early aged hypertension and the effects of green tea flavonoid epigallocatechin-3-gallate (EGCG). Twenty-four rats were divided into three groups: a control Wistar-Kyoto group (WKY, n = 8), a spontaneously early aged hypertensive group (SHR, n = 8), and an early aged hypertension with EGCG treatment group (SHR-EGCG, n = 8; daily oral EGCG 200 mg/kg-94%, 12 weeks). At 48 weeks old, blood pressures (BPs) were evaluated and cerebral cortexes were isolated for TUNEL assay and Western blotting. Systolic, diastolic, and mean blood pressure levels in the SHR-EGCG were reduced compared to the SHR. The percentage of neural cell deaths, the levels of cytosolic Endonuclease G, cytosolic AIF (Caspase-independent apoptotic pathway), Fas, Fas Ligand, FADD, Caspase-8 (Fas-mediated apoptotic pathway), t-Bid, Bax/Bcl-2, Bak/Bcl-xL, cytosolic Cytochrome C, Apaf-1, Caspase-9 (Mitochondrial-mediated apoptotic pathway), and Caspase-3 (Fas-mediated and Mitochondria-mediated apoptotic pathways) were increased in the SHR relative to WKY and reduced in SHR-EGCG relative to SHR. In contrast, the levels of Bcl-2, Bcl-xL, p-Bad, 14-3-3, Bcl-2/Bax, Bcl-xL/Bak, and p-Bad/Bad (Bcl-2 family-related pro-survival pathway), as well as Sirt1, p-PI3K/PI3K and p-AKT/AKT (Sirt1/PI3K/AKT-related pro-survival pathway), were reduced in SHR relative WKY and enhanced in SHR-EGCG relative to SHR. In conclusion, green tea flavonoid epigallocatechin-3-gallate (EGCG) might prevent neural apoptotic pathways and activate neural survival pathways, providing therapeutic effects on early aged hypertension-induced neural apoptosis.

8.
Aging (Albany NY) ; 13(16): 20495-20510, 2021 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-34432648

RESUMEN

The anti-apoptotic and pro-survival effects of exercise training were evaluated on the early aged hypertensive rat cerebral cortex. The brain tissues were analysed from ten sedentary male Wistar Kyoto normotensive rats (WKY), ten sedentary spontaneously 12 month early aged hypertensive rats (SHR), and ten hypertensive rats undergoing treadmill exercise training (60 min/day, 5 days/week) for 12 weeks (SHR-EX). TUNEL-positive apoptotic cells, the expression levels of endonuclease G (EndoG) and apoptosis-inducing factor (AIF) (caspase-independent apoptotic pathway), Fas ligand, Fas death receptor, tumor necrosis factor (TNF)-α, TNF receptor 1, Fas-associated death domain, active caspase-8 and active caspase-3 (Fas-mediated apoptotic pathways) as well as t-Bid, Bax, Bak, Bad, cytochrome c, active caspase 9 and active caspase-3 (mitochondria-mediated apoptotic pathways) were reduced in SHR-EX compared with SHR. Pro-survival Bcl2, Bcl-xL, p-Bad, 14-3-3, insulin-like growth factor (IGF)-1, pPI3K/PI3K, and pAKT/AKT were significantly increased in SHR-EX compared to those in SHR. Exercise training suppressed neural EndoG/AIF-related caspase-independent, Fas/FasL-mediated caspase-dependent, mitochondria-mediated caspase-dependent apoptotic pathways as well as enhanced Bcl-2 family-related and IGF-1-related pro-survival pathways in the early aged hypertensive cerebral cortex. These findings indicated new therapeutic effects of exercise training on preventing early aged hypertension-induced neural apoptosis in cerebral cortex.


Asunto(s)
Apoptosis , Corteza Cerebral/metabolismo , Terapia por Ejercicio , Hipertensión/fisiopatología , Hipertensión/terapia , Animales , Caspasas/genética , Caspasas/metabolismo , Humanos , Hipertensión/genética , Hipertensión/metabolismo , Masculino , Ratas , Ratas Endogámicas WKY , Receptores del Factor de Necrosis Tumoral/genética , Receptores del Factor de Necrosis Tumoral/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
9.
Front Integr Neurosci ; 15: 747901, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35111001

RESUMEN

Neural mitochondrial dysfunction, neural oxidative stress, chronic neuroinflammation, toxic protein accumulation, and neural apoptosis are common causes of neurodegeneration. Elamipretide, a small mitochondrially-targeted tetrapeptide, exhibits therapeutic effects and safety in several mitochondria-related diseases. In neurodegeneration, extensive studies have shown that elamipretide enhanced mitochondrial respiration, activated neural mitochondrial biogenesis via mitochondrial biogenesis regulators (PCG-1α and TFAM) and the translocate factors (TOM-20), enhanced mitochondrial fusion (MNF-1, MNF-2, and OPA1), inhibited mitochondrial fission (Fis-1 and Drp-1), as well as increased mitophagy (autophagy of mitochondria). In addition, elamipretide has been shown to attenuate neural oxidative stress (hydrogen peroxide, lipid peroxidation, and ROS), neuroinflammation (TNF, IL-6, COX-2, iNOS, NLRP3, cleaved caspase-1, IL-1ß, and IL-18), and toxic protein accumulation (Aß). Consequently, elamipretide could prevent neural apoptosis (cytochrome c, Bax, caspase 9, and caspase 3) and enhance neural pro-survival (Bcl2, BDNF, and TrkB) in neurodegeneration. These findings suggest that elamipretide may prevent the progressive development of neurodegenerative diseases via enhancing mitochondrial respiration, mitochondrial biogenesis, mitochondrial fusion, and neural pro-survival pathway, as well as inhibiting mitochondrial fission, oxidative stress, neuroinflammation, toxic protein accumulation, and neural apoptosis. Elamipretide or mitochondrially-targeted peptide might be a targeted agent to attenuate neurodegenerative progression.

10.
Life Sci ; 259: 118187, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32781061

RESUMEN

AIMS: Voluntary exercise training has cardioprotective effects in humans, but the underlying mechanism is unknown. This research was done to estimate the effect of voluntary exercise training to attenuate middle-aged maturity-induced cardiac apoptosis. MATERIALS AND METHODS: The study was designed to divide 64 male mice randomly into four groups, consisting of a 9-month sedentary pre-middle-aged group (9M), 15-month sedentary middle-aged group (15M), and two exercise groups using a voluntary wheel running respectively (9M+EX, 15M+EX). After 3 months, the condition of cardiac apoptosis in different groups was measured by HE dying, TUNEL and DAPI staining, and Western Blot analysis. KEY FINDINGS: TUNEL-positive cells were increased in 15M group compared with 9M group, while decreased in 9M+EX and 15M+EX groups compared with their control groups respectively. Protein levels of AIF, Endo G, TNF-α, TNFR1, TRAF2, TRADD, Fas, FasL, FADD, activated caspase 8, 3, 9, Bax/Bcl2, Bak/BclxL, and tBid were decreased in 9M+EX and 15M+EX groups compared with their control groups respectively. The protein levels of pBad/Bad, 14-3-3, IGF1, IGFR1, pPI3K/PI3K, and pAKT/AKT were more activated in the 9M+EX and 15M+EX groups than those in their control groups respectively. Significant differences were found between 9M group and 15M group for the protein levels of TRAF2, FADD, Bax/Bcl2, tBid and pAKT/AKT. SIGNIFICANCE: Voluntary exercise training as an important lifestyle modification may prevent cardiac widely dispersed apoptosis and enhance cardiac survival at middle-aged maturity.


Asunto(s)
Envejecimiento/fisiología , Apoptosis/fisiología , Corazón/fisiología , Condicionamiento Físico Animal/fisiología , Animales , Etiquetado Corte-Fin in Situ , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias Cardíacas/fisiología , Músculo Esquelético/citología , Músculo Esquelético/fisiología , Carrera/fisiología , Conducta Sedentaria
11.
Bioresour Technol ; 152: 552-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24321292

RESUMEN

Corncob residues (CCR) are cellulose residues of corncob after xylan (hemicellulose) is extracted for production of xylitol. Here, an oleaginous yeast Trichosporon cutaneum ACCC 20271 was screened for lipid fermentation using CCR hydrolysate. The initial carbon-to-nitrogen molar ratio (C/N ratio) and the initial sugar concentration of the CCR hydrolysate were investigated in the lipid fermentation of T. cutaneum ACCC 20271. A C/N ratio gradient was generated by changing the corn steep liquor (CSL) addition and an optimal C/N ratio of 49.3 was obtained. The different initial sugar concentration was obtained by changing the cellulase amount and the lipid titer was enhanced by the increased sugar concentration. To our knowledge, this is the first report on using CCR as the feedstock for lipid fermentation. The lipid titer of 12.3g/L and dry cell weight (DCW) of 38.4 g/L were the highest values among the studies using lignocellulose for lipid production.


Asunto(s)
Fermentación , Lípidos/biosíntesis , Trichosporon/metabolismo , Zea mays/metabolismo , Carbohidratos/farmacología , Fermentación/efectos de los fármacos , Hidrólisis/efectos de los fármacos , Lignina/metabolismo , Nitrógeno/metabolismo , Factores de Tiempo , Trichosporon/efectos de los fármacos , Trichosporon/crecimiento & desarrollo , Zea mays/efectos de los fármacos
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