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1.
Int J Biol Macromol ; 271(Pt 1): 132616, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38795885

RESUMEN

Effective EPR and tumor penetration are bottlenecks in current nanomedicine therapy. Comosol software was utilized to analyze the motion process of nanoparticles (NPs) with different shapes, from blood vessels to tumor tissue, to address this. By calculation, urchin-like NPs experienced higher drag forces than spherical NPs, facilitating their EPR and tumor penetration effects. Thus, urchin-like indocyanine green-loaded hydroxyethyl starch-cholesterol (ICG@HES-CH) NPs were prepared by leveraging the instability of ICG responding to near-infrared light (NIR). Upon NIR exposure, ICG degraded and partly disintegrated ICG@HES-CH NPs, and its morphology transformed from spherical to urchin-like. Vincristine (VC), as a model drug, was loaded in urchin-like ICG@HES-CH NPs for the treatment of lymphoma. A20 lymphoma cells and 3T3-A20 tumor organoids were employed to investigate the influence of shape on NPs' cellular uptake, penetration pathway, and cytotoxicity. It demonstrated that urchin-like ICG@HES-CH NPs mainly transport across the extracellular matrix through intercellular pathways, easily reaching the deep tumor sites and achieving higher cytotoxicity. In vivo VC distribution and anti-tumor results indicated that urchin-like NPs increased VC EPR and penetration ability, lowering VC neurotoxicity and superior anti-tumor effect. Therefore, urchin-like ICG@HES-CH NPs have great translational potential to be used as chemotherapeutic nanocarriers in anticancer therapy.


Asunto(s)
Portadores de Fármacos , Derivados de Hidroxietil Almidón , Verde de Indocianina , Nanopartículas , Verde de Indocianina/química , Verde de Indocianina/farmacología , Animales , Nanopartículas/química , Ratones , Portadores de Fármacos/química , Línea Celular Tumoral , Derivados de Hidroxietil Almidón/química , Derivados de Hidroxietil Almidón/farmacología , Vincristina/farmacología , Vincristina/química , Humanos
2.
J Adv Res ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38636588

RESUMEN

INTRODUCTION: Triple-negative breast cancer (TNBC) represents the most aggressive subtype of breast cancer with an extremely dismal prognosis and few treatment options. As a desmoplastic tumor, TNBC tumor cells are girdled by stroma composed of cancer-associated fibroblasts (CAFs) and their secreted stromal components. The rapidly proliferating tumor cells, together with the tumor stroma, exert additional solid tissue pressure on tumor vasculature and surrounding tissues, severely obstructing therapeutic agent from deep intratumoral penetration, and resulting in tumor metastasis and treatment resistance. OBJECTIVES: Fucoxanthin (FX), a xanthophyll carotenoid abundant in marine algae, has attracted widespread attention as a promising alternative candidate for tumor prevention and treatment. Twist is a pivotal regulator of epithelial to mesenchymal transition, and its depletion has proven to sensitize antitumor drugs, inhibit metastasis, reduce CAFs activation and the following interstitial deposition, and increase tumor perfusion. The nanodrug delivery system co-encapsulating FX and nucleic acid drug Twist siRNA (siTwist) was expected to form a potent anti-TNBC therapeutic cyclical feedback loop. METHODS AND RESULTS: Herein, our studies constituted a novel self-assembled polymer nanomedicine (siTwist/FX@HES-CH) based on the amino-modified hydroxyethyl starch (HES-NH2) grafted with hydrophobic segment cholesterol (CH). The MTT assay, flow cytometry apoptosis analysis, transwell assay, western blot, and 3D multicellular tumor spheroids growth inhibition assay all showed that siTwist/FX@HES-CH could kill tumor cells and inhibit their metastasis in a synergistic manner. The in vivo anti-TNBC efficacy was demonstrated that siTwist/FX@HES-CH remodeled tumor microenvironment, facilitated interstitial barrier crossing, killed tumor cells synergistically, drastically reduced TNBC orthotopic tumor burden and inhibited lung metastasis. CONCLUSION: Systematic studies revealed that this dual-functional nanomedicine that targets both tumor cells and tumor microenvironment significantly alleviates TNBC orthotopic tumor burden and inhibits lung metastasis, establishing a new paradigm for TNBC therapy.

3.
Chem Biol Drug Des ; 103(3): e14495, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38444045

RESUMEN

New indocyanine green (ICG) (IR820) is one of the ICG derivatives and attracts increasing attention for cancer management. However, the unsatisfactory tumor targeting ability of IR820 significantly limits its applications for cancer theranostics. Biotin receptor is overexpressed on the membrane of various tumor cells and biotin modified nanocarriers have been reported to enhance the tumor targeting ability on several tumor types. In this work, biotin-new ICG conjugate (Biotin-SS-IR820) was prepared for tumor-targeted IR820 delivery. Biotin and IR820 were coupled through cystamine. The synthesized Biotin-SS-IR820 was characterized by 1 H NMR, FT-IR and HRMS. The in vitro singlet oxygen generation study shows that Biotin-SS-IR820 exhibits similar singlet oxygen generation as compared to IR820 upon 660 nm laser irradiation (0.8 W/cm2 ). The cellular uptake study shows that Biotin-SS-IR820 shows enhanced cellular uptake amount as compared to IR820 on 4T1 cells. As a result, Biotin-SS-IR820 displays enhanced in vitro photodynamic therapeutic effect against 4T1 cells as compared to IR820. In in vivo biodistribution study, Biotin-SS-IR820 shows enhanced tumor accumulation as compared to IR820. Biotin-SS-IR820 developed in this work shows promising prospects for targeted delivery of IR820 to biotin receptor overexpressed tumors.


Asunto(s)
Biotina , Neoplasias , Humanos , Verde de Indocianina , Distribución Tisular , Oxígeno Singlete , Espectroscopía Infrarroja por Transformada de Fourier
4.
Sensors (Basel) ; 24(2)2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38257719

RESUMEN

For covert communication in lossy channels, it is necessary to consider that the carrier of the hidden watermark will undergo multiple image-processing attacks. In order to ensure that secret information can be extracted without distortion from the watermarked images that have undergone attacks, in this paper, we design a novel fragmented secure communication system. The sender will fragment the secret data to be transmitted and redundantly hide it in a large number of multimodal carriers of messenger accounts on multiple social platforms. The receiver receives enough covert carriers, extracts each fragment, and concatenates the transmitted secret data. This article uses the image carrier as an example to fragment the text file intended for transmission and embeds it into a large number of images, with each fragment being redundant and embedded into multiple images. In this way, at the receiving end, only enough stego images need to be received to extract the information in each image, and then concatenate the final secret file. In order to resist various possible attacks during image transmission, we propose a strong robust image watermarking method. This method adopts a watermark layer based on DFT, which has high embedding and detection efficiency and good invisibility. Secondly, a watermark layer based on DCT is adopted, which can resist translation attacks, JPEG attacks, and other common attacks. Experiments have shown that our watermarking method is very fast; both the embedding time and the extraction time are less than 0.15 s for images not larger than 2000×2000. Our watermarking method has very good invisibility with 41dB PSNR on average. And our watermarking method is more robust than existing schemes and robust to nearly all kinds of attacks. Based on this strong robust image watermarking method, the scheme of fragmenting and hiding redundant transmission content into a large number of images is effective and practical. Our scheme can 100% restore the secret file completely under different RST or hybrid attacks, such as rotation by 1 degree and 5 degrees, scaling by 1.25 and 0.8, and cropping by 10% and 25%. Our scheme can successfully restore the secret file completely even if 30% of received images are lost. When 80% of received images are lost, our scheme can still restore 61.1% of the secret file. If all stego images can be obtained, the original text file can be completely restored.

5.
Opt Lett ; 49(1): 161-164, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134177

RESUMEN

High-order correlated excitonic states, such as biexciton, charged biexciton, and polaron, hold a promising platform in contemporary quantum and nonlinear optics due to their large Bohr radii and thus strong nonlinear interactions. The recently found 2D TMDs further give such excitonic states additional valley properties, with bound state of excitons in opposite valleys in momentum spaces. Despite great efforts that have been made on emission properties of excitonic states, their absorption features, especially the ultrafast absorption dynamics, are rarely reported. Here, we reported the enhanced optical absorption of the high-order charged-excitonic states in monolayer WS2, including singlet, triplet, and semidark trions (3-particle state), and charged biexcitons (5-particle state), by utilizing the interlayer charge transfer-induced photo-doping effect in the graphene-WS2 heterostructure. Depending on recombination rates of doping electrons, absorption intensities of charged complexes exhibit ultrafast decay dynamics, with lifetimes of several picoseconds. Due to many-body interaction, both increasing pump intensity and lattice temperature can broaden these fine excitonic absorption peaks and even reverse the shape of the transient absorption spectrum.

6.
J Integr Plant Biol ; 65(12): 2569-2586, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37861067

RESUMEN

Foxtail millet (Setaria italica), a vital drought-resistant crop, plays a significant role in ensuring food and nutritional security. However, its drought resistance mechanism is not fully understood. N6 -methyladenosine (m6 A) modification of RNA, a prevalent epi-transcriptomic modification in eukaryotes, provides a binding site for m6 A readers and affects plant growth and stress responses by regulating RNA metabolism. In this study, we unveiled that the YT521-B homology (YTH) family gene SiYTH1 positively regulated the drought tolerance of foxtail millet. Notably, the siyth1 mutant exhibited reduced stomatal closure and augmented accumulation of excessive H2 O2 under drought stress. Further investigations demonstrated that SiYTH1 positively regulated the transcripts harboring m6 A modification related to stomatal closure and reactive oxygen species (ROS) scavenging under drought stress. SiYTH1 was uniformly distributed in the cytoplasm of SiYTH1-GFP transgenic foxtail millet. It formed dynamic liquid-like SiYTH1 cytosol condensates in response to drought stress. Moreover, the cytoplasmic protein SiYTH1 was identified as a distinct m6 A reader, facilitating the stabilization of its directly bound SiARDP and ROS scavenging-related transcripts under drought stress. Furthermore, natural variation analysis revealed SiYTH1AGTG as the dominant allele responsible for drought tolerance in foxtail millet. Collectively, this study provides novel insights into the intricate mechanism of m6 A reader-mediated drought tolerance and presents a valuable genetic resource for improving drought tolerance in foxtail millet breeding.


Asunto(s)
Resistencia a la Sequía , Setaria (Planta) , Especies Reactivas de Oxígeno/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Setaria (Planta)/metabolismo , Proteínas de Plantas/metabolismo , Fitomejoramiento , Regulación de la Expresión Génica de las Plantas/genética , Estrés Fisiológico/genética
7.
Nat Commun ; 14(1): 5310, 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37652932

RESUMEN

Controlling the interaction between light and matter at micro- and nano-scale can provide new opportunities for modern optics and optoelectronics. An archetypical example is polariton, a half-light-half-matter quasi particle inheriting simultaneously the robust coherence of light and the strong interaction of matter, which plays an important role in many exotic phenomena. Here, we open up a new kind of cooperative coupling between plasmon and different excitonic complexes in WS2-silver nanocavities, namely plasmon-exciton-trion-charged biexciton four coupling states. Thanks to the large Bohr radius of up to 5 nm, the charged biexciton polariton exhibits strong saturation nonlinearity, ~30 times higher than the neutral exciton polariton. Transient absorption dynamics further reveal the ultrafast many-body interaction nature, with a timescale of <100 fs. The demonstration of biexciton polariton here combines high nonlinearity, simple processing and strong scalability, permitting access for future energy-efficient optical switching and information processing.

8.
Int J Public Health ; 68: 1605564, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37124160

RESUMEN

Objectives: This study aimed to systematically review the effectiveness of service interventions for improving postpartum contraception, including contraceptive use, prevention of repeat pregnancies and induced abortions. Methods: A systematic literature search was conducted in three databases until June 2022 (PROSPERO registration CRD42022328349). Estimates of intervention effects from meta-analyses were represented as odds ratios (OR) with 95% confidence intervals (CI). Results: 16 studies with 14,289 participants were included, with four kinds of interventions recognized. Interventions effect in increasing use of contraceptives and decreasing rates of repeated pregnancy for up to 6 months postpartum (OR = 2.24, 0.06, 95% CI = 1.46-3.44, 0.02-0.22, respectively), with no significant associations with contraceptive use at 12 months postpartum, prevention of postpartum repeat pregnancies and induced abortions during 1 year after childbirth. Conclusion: We concluded that interventions impact the initiation of postpartum contraceptive use and prevention of repeat pregnancy with an overall certainty from low to moderate. These findings highlight the need for additional studies to integrate the beneficial effect of several interventions and then design more feasible strategies, which is important for the maternal and child healthcare systems.


Asunto(s)
Aborto Inducido , Servicios de Salud Materna , Embarazo , Femenino , Niño , Humanos , Anticoncepción , Periodo Posparto , Anticonceptivos
9.
Mater Today Bio ; 20: 100615, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37063775

RESUMEN

TGF-ß is widely existed in tumor microenvironment, taking part in tumorigenesis process including angiogenesis, cancer associated fibroblast (CAF) proliferation, and immunosuppression. It inhibited the activation, proliferation, migration and differentiation of T cells, in which way caused a limited therapeutic effects of chimeric antigen receptor T (CAR-T) towards solid tumor such as lymphoma. To targeted block TGF-ß at tumor site, we take advantages of nano-techniques to deliver TGF-ß inhibitors LY2157299 (LY) towards the tumor sites, in order to help achieve a improved and long-term functions of CAR-T towards lymphoma. Based on amphipathic hydroxyethyl starch-polycaprolactone (HES-PCL), LY and photosensitizer indocyanine green (ICG) were co-loaded in HES-PCL to achieve LY/ICG@HES-PCL nanoparticle. The enhanced function of CAR-T benefited from LY/ICG@HES-PCL were verified through lymphoma Raji cells in vitro and Nod scid gamma mice engrafted with the Raji cells in vivo. LY was targeted transported to tumor site and accelerated release by mild ICG photothermal. Chemokines CXCL9/10/11 â€‹at the tumor site relevant to CAR-T migration and chemokines receptor CXCR3 of CAR-T could be up-regulated by LY, thus facilitated the enhanced accumulation of CAR-T at lymphoma site. T effector memory cells differentiation could also be accelerated by LY/ICG@HES-PCL. Combined therapy of LY/ICG@HES-PCL and CAR-T achieved 2.4 times higher antitumor activity and 2.7 times higher relapse inhibiting rates than CAR-T alone within 15 days and 11 days, respectively. The results suggested that LY/ICG@HES-PCL facilitated the enhanced therapeutic index of CAR-T cells towards lymphoma simply and safely, it may be further potentiated applied for other solid tumors.

10.
Mater Today Bio ; 18: 100542, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36647538

RESUMEN

Chemo-photodynamic therapy shows great potential for cancer treatment. However, the rational integration of chemotherapeutic agents and photosensitizers to construct an intelligent nanoplatform with synergistic therapeutic effect is still a great challenge. In this work, curcumin-loaded reduction-responsive prodrug nanoparticles of new indocyanine green (Cur@IR820-ss-PEG) were developed for synergistic cancer chemo-photodynamic therapy. Cur@IR820-ss-PEG exhibit high drug loading content and special worm-like morphology, contributing to their efficient cellular uptake. Due to the presence of the disulfide bond between IR820 and PEG, Cur@IR820-ss-PEG display reduction responsive drug release behaviors. The efficient cellular uptake and reduction triggered drug release of Cur@IR820-ss-PEG lead to their enhanced in vitro cytotoxicity against 4T1cells as compared to the mixture of IR820 and curcumin (IR820/Cur) under laser irradiation. Besides, Cur@IR820-ss-PEG exhibit prolonged blood half-life time, better tumor accumulation and retention, enhanced tumor hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial cell growth factor (VEGF) suppression effect as compared to IR820/Cur. In vivo antitumor activity study, Cur@IR820-ss-PEG effectively inhibit the tumor angiogenesis, which potentiates the PDT efficacy and leads to the best in vivo antitumor effect of Cur@IR820-ss-PEG. This work provides a novel and relatively simple strategy for synergistic cancer chemo-photodynamic therapy.

11.
Chinese Journal of School Health ; (12): 974-978, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-984471

RESUMEN

Objective@#To examine the exposure to television advertising of unhealthy food among children and adolescents in Beijing, in order to provide a basis for the formulation of marketing management policies with unhealthy food.@*Methods@#Four weekdays and four weekend days were randomly selected during October 19, 2020 to January 17, 2021, excluding holidays and school holidays. The top five popular channels of children and adolescents aged 3 to 18 years old were selected. A total of 720 hours was included for coding and analysis. World Health Organization Nutrient Profile Model for the Western Pacific Region was used to classify food and assess the health level.@*Results@#A total of 13 864 advertisings (ads) was monitored, 38.8% (5 376) of which were food ads. Furthermore, 49.9% (2 680) of food ads were unhealthy food ads, with a frequency of 2.00 per hour per channel. The top five most frequent food ads were infant formula for 12-36 months (26.7%), cheese (16.7%), savory snacks (12.2%), milk drinks (10.5%) and chocolate and candy (6.0%). The most frequently used marketing strategies for unhealthy food ads were brand benefit claims (96.8%) and promotional characters (67.9%).@*Conclusion@#Children and adolescents in Beijing are highly exposed to TV marketing of unhealthy foods. Marketing strategies such as brand benefit claims and promotional characters are employed to boost the impact of unhealthy food ads. There is an urgent need to introduce relevant policies to regulate TV marketing of unhealthy foods.

12.
Front Bioeng Biotechnol ; 11: 1320807, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38312512

RESUMEN

Chimeric antigen receptor (CAR) T cells exhibit promising progress in addressing hematologic malignancies. However, CAR-T therapy for solid tumors remains limited, with no FDA-approved CAR-T products available for clinical use at present. Primary reasons include insufficient infiltration, accumulation, tumor immunosuppression of the microenvironment, and related side effects. Single utilization of CAR-T cannot effectively overcome these unfavorable obstacles. A probable effective pathway to achieve a better CAR-T therapy effect would be to combine the benefits of biomaterials-based technology. In this article, comprehensive biomaterials strategies to break through these obstacles of CAR-T cell therapy at the tumor sites are summarized, encompassing the following aspects: 1) generating orthotopic CAR-T cells; 2) facilitating CAR-T cell trafficking; 3) stimulating CAR-T cell expansion and infiltration; 4) improving CAR-T cell activity and persistence; 5) reprogramming the immunosuppressive microenvironments. Additionally, future requirements for the development of this field, with a specific emphasis on promoting innovation and facilitating clinical translation, are thoroughly discussed.

13.
Nutrients ; 14(15)2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35956286

RESUMEN

Parental coercive and structured feeding practices are linked with children's weight gain. Thus, identifying their predictors will assist in childhood obesity prevention. We explored how parents' concerns and perceptions of children's weight, parenting stress, parenting competence, parents' family roles, and only child status (of both parent and child) predict the use of restriction, pressure to eat, and monitoring practices among parents of preschoolers. Parent-child dyads (n = 2990) were recruited in Beijing in 2019. Parenting competence, parents' weight perceptions and feeding practices were assessed using the Chinese version of Parenting Sense of Competence Scale and Child Feeding Questionnaire (CFQ), respectively. Parenting stress and other variables were collected through self-administered questionnaires. Multivariate linear associations between parents' weight perceptions and feeding practices were significant among normal-weight children. Parents' concerns about children being overweight were positively associated with restriction and monitoring, and negatively associated with pressure to eat. Higher levels of parenting stress and parenting competence significantly improved the adoption of restriction and pressure to eat. Parents' only child status and that of children had an impact on parents' feeding practices. The fathers' feeding preferences were substantially different from what mothers preferred. In conclusion, such parenting and family characteristics significantly influenced feeding practices of preschoolers' parents. These were long neglected in China.


Asunto(s)
Responsabilidad Parental , Obesidad Infantil , Beijing , Índice de Masa Corporal , Peso Corporal , Niño , Estudios Transversales , Composición Familiar , Conducta Alimentaria , Femenino , Humanos , Relaciones Padres-Hijo , Padres , Obesidad Infantil/prevención & control , Encuestas y Cuestionarios
14.
Opt Lett ; 47(15): 3916-3919, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35913347

RESUMEN

Integrating metal halide perovskites onto plasmonic nanostructures has recently become a trending method of enabling superior emissive performance of perovskite nanophotonic devices. In this work, we present an in-depth study on the spontaneous emission properties of hybrid systems comprising CsPbBr3 nanocrystals and silver nanostructures. Specifically, a 5.7-fold increment of the photoluminescence (PL) intensity and a 1.65-fold enhancement of the PL relaxation rate is attained when the transition energy of CsPbBr3 is spectrally resonant with the oscillational frequency of Ag nanodisks (NDs), which is attributed to the intense exciton-plasmon coupling-induced Purcell effect. Furthermore, a 540-fs ultrafast energy transfer from the CsPbBr3 excitons to Ag plasmons is revealed by femtosecond pump-probe experiments, suggesting the key mechanism responsible for the Purcell-enhanced radiative emission. Our finding offers a unique understanding of the enhanced emissive behavior in the plasmon-coupled perovskite system and paves the way for further applications.

15.
Nutrients ; 14(14)2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35889817

RESUMEN

The excessive consumption of sugar-sweetened beverages (SSBs) has been proven to be critical for obesity among preschoolers. This study aimed to describe the SSB consumption rates among preschoolers in the Dongcheng District of Beijing, China, and to explore the association between obesogenic environmental determinants and consumption. We applied a stratified cluster sampling method and recruited 3057 primary caregivers of preschoolers in June 2019 to participate in the survey. The caregivers reported their children's consumption rates of six categories of SSBs and their exposure rates to SSB-related obesogenic environments. The associations between them were tested using multivariate logistic regression models. The mean (SD) age of the children was 5.6 (0.6) years and nearly half (48.3%) were girls. About 84.5% of the children had consumed SSBs over the past three months, and sugar-sweetened milk beverages had the highest consumption rate. Higher exposure to advertisements for the corresponding SSB categories in children, higher frequency rates of consuming SSBs and of taking children to fast-food restaurants in caregivers, and lower frequency rates of reading the Nutrition Facts Panels by caregivers were associated with higher SSB consumption rates among children (p < 0.05 in all of the SSB categories investigated, except for the Nutrition Facts Panel reading behaviors for the sports and energy beverages). SSB consumption among preschoolers is of concern, and comprehensive policy actions and education are urgently needed.


Asunto(s)
Bebidas Azucaradas , Beijing , Bebidas/efectos adversos , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Masculino , Obesidad , Bebidas Azucaradas/efectos adversos
16.
Light Sci Appl ; 11(1): 94, 2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35422032

RESUMEN

Searching for ideal materials with strong effective optical nonlinear responses is a long-term task enabling remarkable breakthroughs in contemporary quantum and nonlinear optics. Polaritons, hybridized light-matter quasiparticles, are an appealing candidate to realize such nonlinearities. Here, we explore a class of peculiar polaritons, named plasmon-exciton polaritons (plexcitons), in a hybrid system composed of silver nanodisk arrays and monolayer tungsten-disulfide (WS2), which shows giant room-temperature nonlinearity due to their deep-subwavelength localized nature. Specifically, comprehensive ultrafast pump-probe measurements reveal that plexciton nonlinearity is dominated by the saturation and higher-order excitation-induced dephasing interactions, rather than the well-known exchange interaction in traditional microcavity polaritons. Furthermore, we demonstrate this giant nonlinearity can be exploited to manipulate the ultrafast nonlinear absorption properties of the solid-state system. Our findings suggest that plexcitons are intrinsically strongly interacting, thereby pioneering new horizons for practical implementations such as energy-efficient ultrafast all-optical switching and information processing.

17.
Nutrients ; 14(4)2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35215450

RESUMEN

The WHO recommends front-of-package labeling (FOPL) to help parents make healthier food choices for their children. But which type of FOPL resonates with parents in China? We performed a cross-sectional study to investigate parental preferences for five widely used formats of FOPL. A multi-stage cluster sampling method was applied to selected parents of students in primary and secondary schools in six provinces and municipalities from July 2020 to March 2021. A close-ended questionnaire was used to collect demographic information, parents' preferences for five FOPL in three dimensions, perceptions of the importance of nutrients labeled on FOPL, and prepackaged foods that need FOPL most. Chi-square tests were used to examine the characteristics among five groups. The results showed that multiple traffic lights (MTL) was preferred by parents, followed by warning labels. Parents thought the most needed nutrients to label were sugar, salt, and total fat. The top three prepackaged foods to label were "baked food", "milk and dairy products" and "sugar-sweetened beverages". Our findings indicate that nutrient-specific FOPL formats with interpretive aids were preferred by Chinese parents. These new findings can help inform the planning and implementation of FOPL in China and help Chinese parents make healthier food choices.


Asunto(s)
Comportamiento del Consumidor , Etiquetado de Alimentos , Niño , China , Conducta de Elección , Estudios Transversales , Etiquetado de Alimentos/métodos , Preferencias Alimentarias , Humanos , Valor Nutritivo , Padres , Formulación de Políticas
18.
Adv Sci (Weinh) ; 9(10): e2105746, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35104054

RESUMEN

The competition between different spatiotemporal carrier relaxation determines the carrier harvesting in optoelectronic semiconductors, which can be greatly optimized by utilizing the ultrafast spatial expansion of highly energetic carriers before their energy dissipation via carrier-phonon interactions. Here, the excited-state dynamics in layered tungsten disulfide (WS2 ) are primarily imaged in the temporal, spatial, and spectral domains by transient absorption microscopy. Ultrafast hot carrier expansion is captured in the first 1.4 ps immediately after photoexcitation, with a mean diffusivity up to 980 cm2 s-1 . This carrier diffusivity then rapidly weakens, reaching a conventional linear spread of 10.5 cm2 s-1 after 2 ps after the hot carriers cool down to the band edge and form bound excitons. The novel carrier diffusion can be well characterized by a cascaded transport model including 3D thermal transport and thermo-optical conversion, in which the carrier temperature gradient and lattice thermal transport govern the initial hot carrier expansion and long-term exciton diffusion rates, respectively. The ultrafast hot carrier expansion breaks the limit of slow exciton diffusion in 2D transition metal dichalcogenides, providing potential guidance for high-performance applications and thermal management of optoelectronic technology.

19.
Cell Mol Biol (Noisy-le-grand) ; 68(9): 68-76, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36905272

RESUMEN

Chronic elevated free fatty acids (FFAs) impair pancreatic ß cells, but the mechanisms remain elusive. In this study, palmitic acid (PA) impaired viability and glucose-stimulated insulin secretion of INS-1 cells. Microarray analysis showed that PA markedly altered the expression of 277 probe sets of genes with 232 upregulated and 45 downregulated (fold change ≥ 2.0 or ≤ -2.0; P < 0.05). Gene Ontology analysis displayed a series of the biological process of the differentially expressed genes, such as intrinsic apoptotic signaling pathway in response to endoplasmic reticulum (ER) stress and oxidative stress, inflammatory response, positive regulation of macroautophagy, regulation of insulin secretion, cell proliferation and cycle, fatty acid metabolic process, glucose metabolic process and so on. Kyoto Encyclopedia of Genes and Genomes analysis demonstrated molecular pathways with which the differentially expressed genes associated, including NOD-like receptor, NF-κB and PI3K-Akt signaling pathways, apoptosis, adipocytokine signaling pathway, ferroptosis, protein processing in ER, fatty acid biosynthesis and cell cycle. Moreover, PA promoted protein expression of CHOP, cleaved caspase-3, microtubule-associated proteins light chain 3 (LC3)-II, NOD-like receptor pyrin domain containing 3 (NLRP3), cleaved IL-1ß and Lcn2, increased reactive oxygen species, apoptosis and the ratio of LC3-II/I, and reduced p62 protein expression, intracellular glutathione peroxidase and catalase levels, suggesting activation of ER stress, oxidative stress, autophagy and NLRP3 inflammasome. The results indicate the impaired role of PA and the global gene expression profile of INS-1 cells following PA intervention, providing new insights into the mechanisms involving the damage of pancreatic ß cells by FFAs.


Asunto(s)
Proteína con Dominio Pirina 3 de la Familia NLR , Ácido Palmítico , Apoptosis/genética , Estrés del Retículo Endoplásmico/genética , Glucosa , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Transcriptoma
20.
Nanoscale ; 13(30): 13030-13041, 2021 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-34477786

RESUMEN

Developing promoters that can boost the growth quality, efficiency, and robustness of two-dimensional (2D) transition metal dichalcogenides is significant for their industrial applications. Herein a new group (group IIA) of promoters in the periodic table has been disclosed, whose chlorides (especially CaCl2 and SrCl2) exhibit a versatile promoting effect on the CVD growth of various TMD monolayers, including hexagonal MoS2, MoSe2, Re doped MoS2, and triclinic ReS2. The promoting effect of group IIA promoters relies on the appropriate dose and is strongly substrate-dependent. The performances of five typical group IA-IIA metal chlorides are ranked by quantitative investigations, displaying periodic variations closely related to the electronegativities of the metal elements. A brand-new acid-base match model is proposed, attributing the promoting mechanism to an increase of the substrate basicity due to the usage of promoters, thus leading to the sufficient adsorption of the acidic precursor. Aberration-corrected annular dark field scanning transmission electron microscopy (ADF-STEM) was applied, unveiling anomalous grain boundaries (GBs) with a low density of coincident sites in the as-grown ReS2 and detailed atomic configurations of Re doped MoS2. This work expands the promoter library and gives an insight into GB engineering for the CVD growth of 2D TMDs.

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