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1.
Opt Express ; 32(4): 6776-6790, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439375

RESUMO

Independently tunable biaxial color pixels, composed of isolated nanosquare dimers, are demonstrated in this study. These pixels are capable of displaying a full range of colors under a linear-polarization dependent reflection mode. The metasurface is constructed by arranging LiNbO3 nanodimers on a PDMS substrate. By exciting a strong magnetic dipole (MD) resonance and effectively suppressing other multipolar resonances using surface lattice resonances, the researchers achieved a single reflection peak with a bandwidth of less than 9 nm and a reflective efficiency of up to 99%. Additionally, the stretchability of the PDMS substrate allows for active and continuous tuning of the metasurface by up to 40% strain, covering almost 150 nm of the visible light spectrum and enabling changes in reflection color. This metasurface holds potential applications in various fields, such as color displays, data storage, and anti-counterfeiting technologies.

2.
Liver Int ; 44(6): 1435-1447, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38483145

RESUMO

BACKGROUND AND AIMS: The use of corticosteroids in chronic drug-induced liver injury (DILI) is an important issue. Our previous randomized controlled trial showed that patients with chronic DILI benefited from a 48-week steroid stepwise reduction (SSR) regimen. However, it remains unclear whether a shorter course of therapy can achieve similar efficacy. In this study, we aimed to assess whether a 36-week SSR can achieve efficacy similar to that of 48-week SSR. METHODS: A randomized open-label trial was performed. Eligible patients were randomly assigned to the 36- or 48-week (1:1) SSR group. Liver biopsies were performed at baseline and at the end of treatment. The primary outcome was the proportion of patients with relapse rate (RR). The secondary outcomes were improvement in liver histology and safety. RESULTS: Of the 90 participants enrolled, 84 (87.5%) completed the trial, and 62 patients (68.9%) were women. Hepatocellular damage was observed in 53.4% of the cohort. The RR was 7.1% in the 36-week SSR group but 4.8% in the 48-week SSR group, as determined by per-protocol set analysis (p = 1.000). Significant histological improvements in histological activity (93.1% vs. 92.9%, p = 1.000) and fibrosis (41.4% vs. 46.4%, p = .701) were observed in both the groups. Biochemical normalization time did not differ between the two groups. No severe adverse events were observed. CONCLUSIONS: Both the 36- and 48-week SSR regimens demonstrated similar biochemical response and histological improvements with good safety, supporting 36-week SSR as a preferable therapeutic choice (ClinicalTrials.gov, NCT03266146).


Assuntos
Fígado , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto , Fígado/patologia , Fígado/efeitos dos fármacos , Doença Hepática Crônica Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Crônica Induzida por Substâncias e Drogas/etiologia , Resultado do Tratamento , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Recidiva , Idoso , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Esquema de Medicação
3.
Phys Chem Chem Phys ; 26(15): 11582-11588, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38533831

RESUMO

The study aimed to investigate the impact of random fluctuations in Schottky barrier formation at polar interfaces between InGaZnO4 (IGZO) and different metals, particularly in the context of device miniaturization. The investigation revealed that different metals can establish various crystalline IGZO interfaces to achieve Ohmic contact, regardless of their work function. Additionally, the study suggests that introducing In doping at the amorphous IGZO interface can effectively reduce the Schottky barrier when in contact with Al metal. These findings provide theoretical guidance for the miniaturization of source-drain contacts in IGZO devices.

4.
Angew Chem Int Ed Engl ; : e202409296, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38923710

RESUMO

Among the various types of materials with intrinsic porosity, porous organic cages (POCs) are distinctive as discrete molecules that possess intrinsic cavities and extrinsic channels capable of facilitating molecular sieving. However, the fabrication of POC membranes remains highly challenging due to the weak noncovalent intermolecular interactions and most reported POCs are powders. In this study, we constructed crystalline free-standing porous organic cage membranes by fortifying intermolecular interactions through the induction of intramolecular hydrogen bonds, which was confirmed by single-crystal X-ray analysis. To elucidate the driving forces behind, a series of terephthaldehyde building blocks containing different substitutions were reacted with flexible triamine under different conditions via interfacial polymerization (IP). Furthermore, density functional theory (DFT) calculations suggest that intramolecular hydrogen bonding can significantly boost the intermolecular interactions. The resulting membranes exhibited fast solvent permeance and high rejection of dyes not only in water, but also in organic solvents. In addition, the membrane demonstrated excellent performance in precise molecular sieving in organic solvents. This work opens an avenue to designing and fabricating free-standing membranes composed of porous organic materials for efficient molecular sieving.

5.
Opt Lett ; 48(7): 1646-1649, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221731

RESUMO

Most ultraviolet (UV) passive optics are currently non-tunable and lack external modulation methods because of the poor tunability of wide-bandgap semiconductor materials in UV working media. This study investigates the excitation of magnetic dipole resonances in the solar-blind UV region by hafnium oxide metasurfaces using elastic dielectric polydimethylsiloxane (PDMS). The near-field interactions between the resonant dielectric elements can be modulated by the mechanical strain of the PDMS substrate, which can flatten the structure's resonant peak beyond the solar-blind UV wavelength range, thereby turning on or off the optical switch in the solar-blind UV region. The device has a facile design and can be used in various applications, such as UV polarization modulation, optical communications, and spectroscopy.

6.
Arterioscler Thromb Vasc Biol ; 42(11): 1324-1332, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36288292

RESUMO

BACKGROUND: Exposure to tobacco or marijuana smoke, or e-cigarette aerosols, causes vascular endothelial dysfunction in humans and rats. We aimed to determine what constituent, or class of constituents, of smoke is responsible for endothelial functional impairment. METHODS: We investigated several smoke constituents that we hypothesized to mediate this effect by exposing rats and measuring arterial flow-mediated dilation (FMD) pre- and post-exposure. We measured FMD before and after inhalation of sidestream smoke from research cigarettes containing normal and reduced nicotine level with and without menthol, as well as 2 of the main aldehyde gases found in both smoke and e-cigarette aerosol (acrolein and acetaldehyde), and inert carbon nanoparticles. RESULTS: FMD was reduced by all 4 kinds of research cigarettes, with extent of reduction ranging from 20% to 46% depending on the cigarette type. While nicotine was not required for the impairment, higher nicotine levels in smoke were associated with a greater percent reduction of FMD (41.1±4.5% reduction versus 19.2±9.5%; P=0.047). Lower menthol levels were also associated with a greater percent reduction of FMD (18.5±9.8% versus 40.5±4.8%; P=0.048). Inhalation of acrolein or acetaldehyde gases at smoke-relevant concentrations impaired FMD by roughly 50% (P=0.001). However, inhalation of inert carbon nanoparticles at smoke-relevant concentrations with no gas phase also impaired FMD by a comparable amount (P<0.001). Bilateral cervical vagotomy blocked the impairment of FMD by tobacco smoke. CONCLUSIONS: There is no single constituent or class of constituents responsible for acute impairment of endothelial function by smoke; rather, we propose that acute endothelial dysfunction by disparate inhaled products is caused by vagus nerve signaling initiated by airway irritation.


Assuntos
Fumar Cigarros , Sistemas Eletrônicos de Liberação de Nicotina , Poluição por Fumaça de Tabaco , Humanos , Ratos , Animais , Nicotiana , Mentol , Acroleína/toxicidade , Nicotina/toxicidade , Aerossóis , Aldeídos , Nervo Vago , Acetaldeído/toxicidade , Gases , Carbono
7.
Mol Biol Rep ; 50(6): 5307-5317, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37155009

RESUMO

BACKGROUND: MiRNAs can affect the radiosensitization of head and neck squamous cell carcinoma (HNSCC). We aimed to analyze the function of miR-125 family members in HNSCC using The Cancer Genome Atlas (TCGA) and determine their effect on radiation in laryngeal squamous cell cancer (LSCC). METHODS: First, we systematically analyzed the role of the miR-125 family in HNSCC using the TCGA database and found that miR-125a-5p is associated with radiotherapy. We then performed comprehensive enrichment analysis of miR-125a-5p and predicted target genes. Then, we performed transfection, cell proliferation assays, reverse transcription polymerase chain reaction, apoptosis assays, micronucleus tests, and western blotting on hep-2 cells selected with puromycin. RESULTS: MiR-125 family members exhibited significantly different expression in HNSCC. They were significantly associated with tumor-node-metastasis staging, clinical stages, and histological grades. Radiation therapy had a statistically effect on miR-125 family members, except miR-125a-3p. Moreover, miR-125a-5p was related to overall survival in LSCC. Thus, we predicted 110 target genes and seven hub genes of miR-125a-5p. The proliferation rate of cells transfected with lentivirus vector expressing miR-125a-5p was significantly reduced compared to the other groups. The radiation effect was enhanced in cells transfected with miR-125a-5p. The ratio of apoptotic cells transfected and exposed to X-rays (10 Gy) was distinctly higher than that of the Ad-control group. Western blotting analysis revealed that miR-125a-5p upregulated the apoptotic regulators P53 and rH2AX. Thus, miR-125a-5p may increase radiosensitivity in LSCC via upregulation of pro-apoptotic genes. CONCLUSIONS: MiR-125 family members could be prognostic biomarkers of HNSCC and improve HNSCC sensitivity to radiotherapy by activating P53. Upregulating miR-125a-5p via lentivirus vectors may be a novel strategy to strengthen the effect of radiotherapy on LSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , MicroRNAs , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , MicroRNAs/genética , Tolerância a Radiação/genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/radioterapia , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética
8.
Altern Ther Health Med ; 29(6): 370-376, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37384400

RESUMO

Objective: This study evaluated the efficacy and safety of bionic tiger bone powder (Jintiange) in comparison to placebo in treating knee osteoarthritis osteoporosis. Methods: A total of 248 patients were randomly allocated to a Jintiange group or a placebo group, undergoing 48 weeks of double-blind treatment. The Lequesne index, clinical symptoms, safety index (adverse events), and Patient's Global Impression of Change score were recorded at pre-determined time intervals. All P values ≤ .05 were deemed statistically significant. Results: Both groups showed a decreasing trend in the Lequesne index, with the Jintiange group's reduction significantly larger from the 12th week (P ≤ .01). Similarly, the effective rate of Lequesne score in the Jintiange group was significantly higher (P < .001). After 48 weeks, clinical symptom score differences between the Jintiange group (2.46 ± 1.74) and the placebo group (1.51 ± 1.73) were statistically significant (P < .05), as were differences in the Patient's Global Impression of Change score (P < .05). Adverse drug reactions were minimal with no significant difference between the groups (P > .05). Conclusion: Jintiange demonstrated superior efficacy over placebo in treating knee osteoporosis, with comparable safety profiles. Findings warrant further comprehensive real-world studies.


Assuntos
Osteoartrite do Joelho , Osteoporose , Humanos , Método Duplo-Cego , Osteoartrite do Joelho/tratamento farmacológico , Pós/uso terapêutico , Resultado do Tratamento
9.
Sensors (Basel) ; 23(13)2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37448094

RESUMO

The authors wish to make the following corrections to the original paper [...].

10.
Sensors (Basel) ; 23(6)2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36991843

RESUMO

In high dynamic scenes, fringe projection profilometry (FPP) may encounter fringe saturation, and the phase calculated will also be affected to produce errors. This paper proposes a saturated fringe restoration method to solve this problem, taking the four-step phase shift as an example. Firstly, according to the saturation of the fringe group, the concepts of reliable area, shallow saturated area, and deep saturated area are proposed. Then, the parameter A related to the reflectivity of the object in the reliable area is calculated to interpolate A in the shallow and deep saturated areas. The theoretically shallow and deep saturated areas are not known in actual experiments. However, morphological operations can be used to dilate and erode reliable areas to produce cubic spline interpolation areas (CSI) and biharmonic spline interpolation (BSI) areas, which roughly correspond to shallow and deep saturated areas. After A is restored, it can be used as a known quantity to restore the saturated fringe using the unsaturated fringe in the same position, the remaining unrecoverable part of the fringe can be completed using CSI, and then the same part of the symmetrical fringe can be further restored. To further reduce the influence of nonlinear error, the Hilbert transform is also used in the phase calculation process of the actual experiment. The simulation and experimental results validate that the proposed method can still obtain correct results without adding additional equipment or increasing projection number, which proves the feasibility and robustness of the method.

11.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(3): 565-573, 2023 May.
Artigo em Zh | MEDLINE | ID: mdl-37248585

RESUMO

Objective: To explore the protective effect of placenta-derived mesenchymal stem cells (P-MSCs) transplantation on intestinal injury in septic mice and its mechanism. Methods: A total of 24 mice were randomly assigned to 3 groups, a sham operation group, a sepsis group that underwent cecal ligation and puncture (CLP) procedure, and a group that received CLP and P-MSCs treatment. Hereinafter, the three groups are referred to as the Sham group, the CLP group, and the CLP+P-MSCs group. For the mice in the Sham group, the abdomen was cut open and the cecum was exposed and then placed back in the abdomen. CLP was performed in the other two groups to establish the sepsis model. Mice in the Sham and the CLP groups received 0.1 mL of 0.9% NaCl injection in the tail vein 1 hour after operation, while mice in the CLP+P-MSCs group received 2×10 5 P-MSCs infusion 1 hour after operation. Intestinal and blood specimens were collected from the mice in each group 24 hours after P-MSCs transplantation. Hematoxylin and eosin (HE) staining of the intestinal tissue was performed for pathological evaluation. The serum concentrations of D-lactic acid, diamine oxidase (DAO), endotoxin, interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, IL-6, IL-10, and transforming growth factor (TGF)-ß were determined by enzyme linked immunosorbent assay (ELISA). The gene expression of the relevant inflammatory factors in the small intestinal tissue was determined by real-time fluorescence polymerase chain reaction. The expression of zonula occludens protein-1 (ZO-1) and occludin protein in the intestine was determined by Western blot, the infiltration of intestinal macrophages was determined by immunohistochemical method, and the polarization of macrophages was determined by immunofluorescence. Results: The exogenous transplantation of P-MSCs could form colonies in the injured intestines of septic mice. Compared with those of the CLP group, the intestinal injury of the CLP+P-MSCs group was significantly alleviated, the serum concentrations of D-lactic acid, DAO, endotoxin, IL-1ß, IL-6, and TNF-α were significantly decreased ( P<0.05), while the serum concentrations of IL-10 and TGF-ß were significantly increased ( P<0.05), the expression levels of IL-1 ß, TNF-α and IL-6 genes in the intestinal tissue were significantly decreased ( P<0.05), while the expression levels of IL-10 and TGF-ß genes were significantly increased ( P<0.05), and the expression of ZO-1 and occludin proteins in the intestine was also significantly increased ( P<0.05). In addition, the distribution of macrophages in the intestinal tissue of the CLP+P-MSCs group decreased significantly and the macrophages showed a tendency for M2 polarization. Conclusion: Exogenous transplantation of P-MSCs can significantly reduce inflammatory injury and improve the intestinal barrier function in septic mice with intestinal injury. Reduction in the infiltration of macrophages and promotion of the polarization of macrophages from M1 to M2 may be the mechanisms underlying the reduction of inflammation.


Assuntos
Transplante de Células-Tronco Mesenquimais , Sepse , Camundongos , Animais , Fator de Necrose Tumoral alfa , Interleucina-10 , Interleucina-6 , Ocludina , Fator de Crescimento Transformador beta , Sepse/terapia , Ácido Láctico
12.
Biochem Biophys Res Commun ; 600: 54-59, 2022 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-35189497

RESUMO

Plants have evolved immune systems to fight against pathogens. However, it is still largely unknown how the plant immunity is finely regulated. Here we identified a BTB/POZ domain-containing protein, namely NbBTB, which is predicted to be a member of the ubiquitin E3 ligase complex. The NbBTB expression is downregulated upon the oomycete pathogen Phytophthora parasitica infection. Overexpression of NbBTB in Nicotiana benthamiana promoted plant susceptibility to P. parasitica infection, and silencing NbBTB increased plant resistance to P. parasitica, indicating that NbBTB negatively modulates plant basal defense. Interestingly, overexpressing or silencing NbBTB did not affect plant resistance to two bacterial pathogens Ralstonia solanacearum and Pseudomonas syringae, suggesting that NbBTB is specifically involved in basal defense against oomycete pathogen. Expression of NbBTB suppressed hypersensitive response (HR) triggered by avirulence proteins from both R. sonanacearum and P. infestans, and silencing NbBTB showed the opposite effect, indicating that NbBTB negatively regulates effector-triggered immunity (ETI). Protein accumulation of avirulence effectors in NbBTB-silenced plants was significantly enhanced, suggesting that NbBTB is likely to negatively modulate ETI by affecting effector protein accumulation. Together, our results demonstrated that NbBTB is a negative regulator in both plant basal defense and ETI.


Assuntos
Domínio BTB-POZ , Ralstonia solanacearum , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/microbiologia , Imunidade Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas/metabolismo , Nicotiana/metabolismo
13.
Langmuir ; 38(1): 363-373, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34931824

RESUMO

With the rapid development of nanotechnology, stimuli-responsive nanomaterials have provided an alternative for designing controllable drug delivery systems due to their spatiotemporally controllable properties. The environment of the human body is complex and cancer cells proliferate rapidly; the traditional nanocarriers could not release the loaded drugs sufficiently, and the release level of the drug is not sufficient for the requirement of treatment. Herein, a photoresponsive, glutathione, and reactive oxygen species block copolymer mPEG2k-ONB-SS-PO-mPEG2k is prepared by Cu(I)-catalyzed azide-alkyne cycloaddition click polymerization. The ο-nitrobenzyl groups, peroxalate ester bonds, disulfide bonds, and triazole units are regularly and repeatedly arranged in hydrophobic blocks. The photo, oxidative, and reductive responsive characteristics of the copolymers in different conditions were investigated by ultraviolet and visible spectrophotometry, dynamic light scattering, and transmission electron microscopy. Nile Red is encapsulated into the core of micelles as a model drug and exhibits the drug release behaviors in various environments. This research provides a way to design potential drug carriers and a promising platform for efficient intracellular drug delivery in cancer therapy.


Assuntos
Micelas , Polímeros , Preparações de Ação Retardada , Doxorrubicina , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Humanos , Estresse Oxidativo
14.
Environ Res ; 210: 112946, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35167848

RESUMO

Adverse impacts of prenatal or postnatal ambient particulate matter exposure have been identified on offspring neurodevelopment. However, it is unclear whether the effect in the two exposure periods is different for early childhood neurodevelopment. This study aimed to evaluate and compare the associations of prenatal and early postnatal exposure to ambient particulate matter with offspring neurodevelopment at 2 years of age and to identify which period was more sensitive to the effects of ambient particulate matter on offspring neurodevelopment. A total of 1331 mother-child pairs from a birth cohort were included in this study from October 2013 to September 2014 in Wuhan, China. The concentrations of ambient daily fine particulate matter (PM2.5) and particulate matter less than 10 µm in aerodynamic diameter (PM10) at each participant's home address during pregnancy and the first two years after birth were estimated by land-use regression models (LUR). Offspring neurodevelopment was measured by the Chinese revision of Bayley Scale of Infant Development (BSID-CR) for each child at 2 years of age. Mental developmental index (MDI) and psychomotor developmental index (PDI) from the BSID-CR were used as outcome variables. A generalized estimating equation (GEE) model was used to estimate the associations of prenatal and postnatal PM2.5 and PM10 exposure with offspring neurodevelopment. After adjusting for potential confounders, we found that both prenatal and early postnatal exposure to PM2.5 and PM10 were associated with decreased offspring MDI and PDI scores. Compared with prenatal exposure, the associations of early postnatal exposure to PM2.5 and PM10 with offspring MDI and PDI were stronger. This study indicates that exposure to ambient particulate matters, mainly during early postnatal period and to a lesser extent prenatally, is associated with impaired offspring neurodevelopment.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Efeitos Tardios da Exposição Pré-Natal , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Coorte de Nascimento , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Exposição Materna/efeitos adversos , Material Particulado/análise , Material Particulado/toxicidade , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Vitaminas
15.
Sensors (Basel) ; 22(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36502089

RESUMO

An improved three-frequency heterodyne synthesis phase unwrapping method is proposed to improve the measurement accuracy through phase difference and phase sum operations. This method can reduce the effect of noise and increase the equivalent phase frequency. According to the distribution found in the phase difference calculation process, the Otsu segmentation is introduced to judge the phase threshold. The equivalent frequency obtained from the phase sum is more than those of all projected fringe patterns. In addition, the appropriate period combinations are also studied. The simulations and related experiments demonstrate the feasibility of the proposed method and the ability to improve the accuracy of the measurement results further.

16.
J Cell Physiol ; 236(9): 6441-6456, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33565085

RESUMO

Senescence of nucleus pulposus (NP) cells (NPC) is a major cause of intervertebral disc degeneration (IVDD), so delay NPC senescence may be beneficial for mitigating IVDD. We studied the effect and mechanism of silent information regulator 2 homolog 3 (SIRT3) on NPC senescence in vivo and in vitro. First, we observed SIRT3 expression in normal and degenerated NPC with immunohistochemical and immunofluorescence staining. Second, using SIRT3 lentivirus transfection, reactive oxygen species probe, senescence-associated ß-galactosidase staining, polymerase chain reaction, and western blot to observe the oxidative stress, senescence, and degeneration degree among groups. Subsequently, pretreatment with adenosine monophosphate-activated protein kinase (AMPK) agonists and inhibitors, observing oxidative stress, senescence, and degeneration degree among groups. Finally, the IVDD model was constructed and divided into Ctrl, Vehicle, LV-shSIRT3, and LV-SIRT3 groups. X-ray and magnetic resonance imaging scans were performed on rat's tails after 1 week; hematoxylin and eosin and safranin-O staining were used to evaluate the degree of IVDD; immunofluorescence staining was used to observe SIRT3 expression; immunohistochemical staining was used to observe oxidative stress, senescence, and degeneration degree of NP. We found that SIRT3 expression is reduced in degenerated NP tissues but increased in H2 O2 -induced NPC. Moreover, SIRT3 upregulation decreased oxidative stress, delayed senescence, and degeneration of NPC. In addition, activation of the AMPK/PGC-1α pathway can partially mitigate the NPC oxidative stress, senescence, and degeneration caused by SIRT3 knockdown. The study in vivo revealed that local SIRT3 overexpression can significantly reduce oxidative stress and ECM degradation of NPC, delay NPC senescence, thereby mitigating IVDD. In summary, SIRT3 mediated by the AMPK/PGC-1α pathway mitigates IVDD by delaying oxidative stress-induced NPC senescence.


Assuntos
Senescência Celular , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Núcleo Pulposo/patologia , Estresse Oxidativo , Sirtuína 3/metabolismo , Adenilato Quinase/metabolismo , Adulto , Animais , Modelos Animais de Doenças , Feminino , Humanos , Peróxido de Hidrogênio/toxicidade , Degeneração do Disco Intervertebral/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Núcleo Pulposo/diagnóstico por imagem , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Punções , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
17.
Opt Express ; 29(20): 32491-32504, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615318

RESUMO

Dynamic color modulation in the composite structure of a graphene microelectromechanical system (MEMS)-photonic crystal microcavity is investigated in this work. The designed photonic crystal microcavity has three resonant standing wave modes corresponding to the three primary colors of red (R), green (G) and blue (B), forming strong localization of light in three modes at different positions of the microcavity. Once graphene is added, it can govern the transmittance of three modes. When graphene is located in the antinode of the standing wave, it has strong light absorption and therefore the structure's transmittance is lower, and when graphene is located in the node of the standing wave, it has weak light absorption and therefore the structure's transmittance is higher. Therefore, the graphene absorption of different colors of light can be regulated dynamically by applying voltages to tune the equilibrium position of the graphene MEMS in the microcavity, consequently realizing the output of vivid monochromatic light or multiple mixed colors of light within a single pixel, thus greatly improving the resolution. Our work provides a route to dynamic color modulation with graphene and provides guidance for the design and manufacture of high resolution, fast modulation and wide color gamut interferometric modulator displays.

18.
Opt Lett ; 46(19): 4952-4955, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598241

RESUMO

Active light manipulation plays a critical role in nanophotonics. In this Letter, we investigate the modulation properties of magnetic dipole (MD) emission based on the phase change material Ge2Sb2Te5 hollow nanodisk (GST-HND). The results show that the amorphous GST-HND supports a strong MD response with a radiative decay enhancement of 282 times and quantum efficiency of 100%. More importantly, by tuning the crystallization rate of GST, the active manipulation of MD radiation is achieved with a quantum efficiency modulation depth of up to 95% at a specific wavelength. Our work may provide significant instruction for the active tuning of optical nanodevices.

19.
Inorg Chem ; 60(7): 5362-5366, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33756074

RESUMO

The two novel organic hybrid iodoplumbates [Hhbpt]2[H2hbpt][H4hbpt][Pb5I18]·9H2O (1, hbpt = 1H-3,5- bis(pyrazinyl)-1,2,4-triazole) and [Pb2I(bpt)2(H2O)3(I3·1/2I2)] (2) were synthesized under hydrothermal conditions. 1 contains a new type of pentanuclear cluster [Pb5I18]8- anion, while 2 comprises an unprecedented 2-D polyiodoplumbate layer. Both 1 and 2 are potential semiconductors with narrow absorption edges of 1.98 eV for 1 and 1.38 eV for 2. 2 also shows photocurrent response and photoluminescent properties.

20.
Environ Res ; 194: 110596, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33307083

RESUMO

With the global lockdown, meteorological factors are highly discussed for COVID-19 transmission. In this study, national-specific and region-specific data sets from Germany, Italy, Spain and the United Kingdom were used to explore the effect of temperature, absolute humidity and diurnal temperature range (DTR) on COVID-19 transmission. From February 1st to November 1st, a 7-day COVID-19 case doubling time (Td), meteorological factors with cumulative 14-day-lagged, government response index and other factors were fitted in the distributed lag nonlinear models. The overall relative risk (RR) of the 10th and the 25th percentiles temperature compared to the median were 0.0074 (95% CI: 0.0023, 0.0237) and 0.1220 (95% CI: 0.0667, 0.2232), respectively. The pooled RR of lower (10th, 25th) and extremely high (90th) absolute humidity were 0.3266 (95% CI: 0.1379, 0.7734), 0.6018 (95% CI: 0.4693, 0.7718) and 0.3438 (95% CI: 0.2254, 0.5242), respectively. While the DTR did not have a significant effect on Td. The total cumulative effect of temperature (10th) and absolute humidity (10th, 90th) on Td increased with the change of lag days. Similarly, a decline in temperature and absolute humidity at cumulative 14-day-lagged corresponded to the lower RR on Td in pooled region-specific effects. In summary, the government responses are important factors in alleviating the spread of COVID-19. After controlling that, our results indicate that both the cold and the dry environment also likely facilitate the COVID-19 transmission.


Assuntos
COVID-19 , China , Controle de Doenças Transmissíveis , Europa (Continente) , Alemanha , Governo , Humanos , Umidade , Itália , Conceitos Meteorológicos , SARS-CoV-2 , Espanha , Temperatura , Reino Unido
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