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1.
Plants (Basel) ; 13(8)2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38674501

RESUMEN

High temperatures have adverse effects on the yield and quality of vegetables. Bok choy, a popular vegetable, shows varying resistance to heat. However, the mechanism underlying the thermotolerance of bok choy remains unclear. In this study, 26 bok choy varieties were identified in screening as being heat-resistant at the seedling stage; at 43 °C, it was possible to observe obvious heat damage in different bok choy varieties. The physiological and biochemical reactions of a heat-tolerant cultivar, Jinmei (J7), and a heat-sensitive cultivar, Sanyueman (S16), were analyzed in terms of the growth index, peroxide, and photosynthetic parameters. The results show that Jinmei has lower relative conductivity, lower peroxide content, and higher total antioxidant capacity after heat stress. We performed transcriptome analysis of the two bok choy varieties under heat stress and normal temperatures. Under heat stress, some key genes involved in sulfur metabolism, glutathione metabolism, and the ribosome pathway were found to be significantly upregulated in the heat-tolerant cultivar. The key genes of each pathway were screened according to their fold-change values. In terms of sulfur metabolism, genes related to protease activity were significantly upregulated. Glutathione synthetase (GSH2) in the glutathione metabolism pathway and the L3e, L23, and S19 genes in the ribosomal pathway were significantly upregulated in heat-stressed cultivars. These results suggest that the total antioxidant capacity and heat injury repair capacity are higher in Jinmei than in the heat-sensitive variety, which might be related to the specific upregulation of genes in certain metabolic pathways after heat stress.

2.
Neuron ; 112(11): 1815-1831.e4, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38492574

RESUMEN

Efforts on developing transient receptor potential vanilloid 1 (TRPV1) drugs for pain management have been hampered by deleterious hypo- or hyperthermia caused by TRPV1 agonists/antagonists. Here, we compared the effects of four antagonists on TRPV1 polymodal gating and core body temperature (CBT) in Trpv1+/+, Trpv1-/-, and Trpv1T634A/T634A. Neither the effect on proton gating nor drug administration route, hair coverage, CBT rhythmic fluctuations, or inflammation had any influence on the differential actions of TRPV1 drugs on CBT. We identified the S4-S5 linker region exposed to the vanilloid pocket of TRPV1 to be critical for hyperthermia associated with certain TRPV1 antagonists. PSFL2874, a TRPV1 antagonist we discovered, is effective against inflammatory pain but devoid of binding to the S4-S5 linker and inducing CBT changes. These findings implicate that biased allosteric mechanisms exist for TRPV1 coupling to nociception and CBT regulation, opening avenues for the development of non-opioid analgesics without affecting CBT.


Asunto(s)
Temperatura Corporal , Nocicepción , Canales Catiónicos TRPV , Canales Catiónicos TRPV/metabolismo , Canales Catiónicos TRPV/genética , Animales , Ratones , Regulación Alostérica/efectos de los fármacos , Nocicepción/efectos de los fármacos , Nocicepción/fisiología , Temperatura Corporal/efectos de los fármacos , Analgésicos/farmacología , Masculino , Humanos , Ratones Endogámicos C57BL , Ratones Noqueados , Dolor/metabolismo , Dolor/tratamiento farmacológico
3.
Glob Chall ; 8(2): 2300023, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38356682

RESUMEN

Self-powered wearable thermoelectric (TE) devices significantly reduce the inconvenience caused to users, especially in daily use of portable devices and monitoring personal health. The textile-based TE devices (TETs) exhibit the excellent flexibility, deformability, and light weight, which fulfill demands of long-term wearing for the human body. In comparison to traditional TE devices with their longstanding research history, TETs are still in an initial stage of growth. In recent years, TETs to provide electricity for low-power wearable electronics have attracted increasing attention. This review summarizes the recent progress of TETs from the points of selecting TE materials, scalable fabrication methods of TE fibers/yarns and TETs, structure design of TETs and reported high-performance TETs. The key points to develop TETs with outstanding TE properties and mechanical performance and better than available optimization strategies are discussed. Furthermore, remaining challenges and perspectives of TETs are also proposed to suggest practical applications for heat harvesting from human body.

4.
Comput Biol Med ; 171: 108147, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38387385

RESUMEN

Instance segmentation plays an important role in the automatic diagnosis of cervical cancer. Although deep learning-based instance segmentation methods can achieve outstanding performance, they need large amounts of labeled data. This results in a huge consumption of manpower and material resources. To solve this problem, we propose an unsupervised cervical cell instance segmentation method based on human visual simulation, named HVS-Unsup. Our method simulates the process of human cell recognition and incorporates prior knowledge of cervical cells. Specifically, firstly, we utilize prior knowledge to generate three types of pseudo labels for cervical cells. In this way, the unsupervised instance segmentation is transformed to a supervised task. Secondly, we design a Nucleus Enhanced Module (NEM) and a Mask-Assisted Segmentation module (MAS) to address problems of cell overlapping, adhesion, and even scenarios involving visually indistinguishable cases. NEM can accurately locate the nuclei by the nuclei attention feature maps generated by point-level pseudo labels, and MAS can reduce the interference from impurities by updating the weight of the shallow network through the dice loss. Next, we propose a Category-Wise droploss (CW-droploss) to reduce cell omissions in lower-contrast images. Finally, we employ an iterative self-training strategy to rectify mislabeled instances. Experimental results on our dataset MS-cellSeg, the public datasets Cx22 and ISBI2015 demonstrate that HVS-Unsup outperforms existing mainstream unsupervised cervical cell segmentation methods.


Asunto(s)
Neoplasias del Cuello Uterino , Humanos , Femenino , Simulación por Computador , Neoplasias del Cuello Uterino/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador
5.
Comput Struct Biotechnol J ; 23: 295-308, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38173879

RESUMEN

P2X receptors (P2X1-7) are non-selective cation channels involved in many physiological activities such as synaptic transmission, immunological modulation, and cardiovascular function. These receptors share a conserved mechanism to sense extracellular ATP. TNP-ATP is an ATP derivative acting as a nonselective competitive P2X antagonist. Understanding how it occupies the orthosteric site in the absence of agonism may help reveal the key allostery during P2X gating. However, TNP-ATP/P2X complexes (TNP-ATP/human P2X3 (hP2X3) and TNP-ATP/chicken P2X7 (ckP2X7)) with distinct conformations and different mechanisms of action have been proposed. Whether these represent species and subtype variations or experimental differences remains unclear. Here, we show that a common mechanism of TNP-ATP recognition exists for the P2X family members by combining enhanced conformation sampling, engineered disulfide bond analysis, and covalent occupancy. In this model, the polar triphosphate moiety of TNP-ATP interacts with the orthosteric site, while its TNP-moiety is deeply embedded in the head and dorsal fin (DF) interface, creating a restrictive allostery in these two domains that results in a partly enlarged yet ion-impermeable pore. Similar results were obtained from multiple P2X subtypes of different species, including ckP2X7, hP2X3, rat P2X2 (rP2X2), and human P2X1 (hP2X1). Thus, TNP-ATP uses a common mechanism for P2X recognition and modulation by restricting the movements of the head and DF domains which are essential for P2X activation. This knowledge is applicable to the development of new P2X inhibitors.

6.
Br J Pharmacol ; 181(8): 1203-1220, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37921202

RESUMEN

BACKGROUND AND PURPOSE: The P2X3 receptor, a trimeric ionotropic purinergic receptor, has emerged as a potential therapeutic target for refractory chronic cough (RCC). Nevertheless, gefapixant/AF-219, the only marketed P2X3 receptor antagonist, might lead taste disorders by modulating the human P2X2/3 (hP2X2/3) heterotrimer. Hence, in RCC drug development, compounds exhibiting strong affinity for the hP2X3 homotrimer and a weak affinity for the hP2X2/3 heterotrimer hold promise. An example of such a molecule is sivopixant/S-600918, a clinical Phase II RCC candidate with a reduced incidence of taste disturbance compared to gefapixant. Sivopixant and its analogue, (3-(4-([3-chloro-4-isopropoxyphenyl]amino)-3-(4-methylbenzyl)-2,6-dioxo-3,6-dihydro-1,3,5-triazin-1(2H)-yl)propanoic acid (DDTPA), exhibit both high affinity and high selectivity for hP2X3 homotrimers, compared with hP2X2/3 heterotrimers. The mechanism underlying the druggable site and its high selectivity remains unclear. EXPERIMENTAL APPROACH: To analyse mechanisms that distinguish this drug candidate from other inhibitors of the P2X3 receptors we used a combination of chimera construction, site covalent occupation, metadynamics, mutagenesis and whole-cell recording. KEY RESULTS: The high affinity and selectivity of sivopixant/DDTPA for hP2X3 receptors was determined by the tri-symmetric site located close to the upper vestibule. Substitution of only four amino acids inside the upper body domain of hP2X2 with those of hP2X3, enabled the hP2X2/3 heterotrimer to exhibit a similar level of apparent affinity for sivopixant/DDTPA as the hP2X3 homotrimer. CONCLUSION AND IMPLICATIONS: From the receptor-ligand recognition perspective, we have elucidated the molecular basis of novel RCC clinical candidates' cough-suppressing properties and reduced side effects, offering a promising approach to the discovery of novel drugs that specifically target P2X3 receptors.


Asunto(s)
Compuestos de Anilina , Bencenosulfonamidas , Carcinoma de Células Renales , Neoplasias Renales , Pirimidinas , Triazinas , Humanos , Carcinoma de Células Renales/inducido químicamente , Piridinas/uso terapéutico , Antagonistas del Receptor Purinérgico P2X/farmacología , Antagonistas del Receptor Purinérgico P2X/uso terapéutico , Tos/inducido químicamente , Receptores Purinérgicos P2X3 , Sulfonamidas , Neoplasias Renales/inducido químicamente , Receptores Purinérgicos P2X2
7.
Phys Chem Chem Phys ; 25(41): 28230-28240, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37823325

RESUMEN

Carbon-quantum-dot-based fluorescence sensing of Hg2+ is a well-known cost-effective tactic with fast response and high sensitivity, while rationally constructing heteroatom-doped carbon quantum dots with improved fluorescence sensing performances through tuning the electronic and chemical structures of the reactive site still remains a challenging project for monitoring trace Hg2+ in aquatic ecosystems to avoid harm resulting from its high toxicity, nonbiodegradabilty and accumulative effects on human health. Herein, intriguing N,S-codoped carbon quantum dots were synthesized via a facile one-step hydrothermal procedure. As an admirable fluorescent probe with plentiful heteroatom-related functional groups, these N,S-codoped carbon quantum dots can exhibit an absolute fluorescence quantum yield as high as 11.6%, excellent solubility and stability over three months, remarkable sensitivity for Hg2+ detection with an attractive detection limit of 0.27 µg L-1 and admirable selectivity for Hg2+ against thirteen other metal ions. Density functional theory calculations reveal that electron-enriched meta-S of the unique graphitic N with homocyclic meta-thiophene sulfur structure can regulate this N site to have more electrons and preferable affinity towards Hg, hence achieving enhanced fluorescence quenching due to greater charge transfer from N to Hg after the coordination interaction. This strategy provides a promising avenue for precisely designing purpose-made quantum dots with the dedicated fluorescence sensing applications.

8.
Plant Cell ; 36(1): 158-173, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-37804093

RESUMEN

Induction of the pluripotent cell mass termed callus from detached organs or tissues is an initial step in typical in vitro plant regeneration, during which auxin-induced ectopic activation of root stem cell factors is required for subsequent de novo shoot regeneration. While Arabidopsis (Arabidopsis thaliana) AUXIN RESPONSE FACTOR 7 (ARF7) and ARF19 and their downstream transcription factors LATERAL ORGAN BOUNDARIES DOMAIN (LBD) are known to play key roles in directing callus formation, the molecules responsible for activation of root stem cell factors and thus establishment of callus pluripotency are unclear. Here, we identified Arabidopsis WRKY23 and BASIC HELIX-LOOP-HELIX 041 (bHLH041) as a transcriptional activator and repressor, respectively, of root stem cell factors during establishment of auxin-induced callus pluripotency. We show that auxin-induced WRKY23 downstream of ARF7 and ARF19 directly activates the transcription of PLETHORA 3 (PLT3) and PLT7 and thus that of the downstream genes PLT1, PLT2, and WUSCHEL-RELATED HOMEOBOX 5 (WOX5), while LBD-induced removal of bHLH041 derepresses the transcription of PLT1, PLT2, and WOX5. We provide evidence that transcriptional activation by WRKY23 and loss of bHLH041-imposed repression act synergistically in conferring shoot-regenerating capability on callus cells. Our findings thus disclose a transcriptional mechanism underlying auxin-induced cellular reprogramming, which, together with previous studies, outlines the molecular framework of auxin-induced pluripotent callus formation for in vitro plant regeneration programs.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/fisiología , Proteínas de Arabidopsis/metabolismo , Activación Transcripcional , Factores de Transcripción/metabolismo , Ácidos Indolacéticos , Regulación de la Expresión Génica de las Plantas/genética , Raíces de Plantas/metabolismo
9.
Org Lett ; 25(29): 5486-5491, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37470382

RESUMEN

Controllable oxidation of alcohols to carbonyls is one of the fundamental transformations in organic chemistry. Herein, we report an unprecedented visible-light-mediated metal-free oxidation of alcohols to carbonyls with hydrogen evolution. By synergistic combination of organophotocatalyst 4CzIPN and a thiol hydrogen atom transfer catalyst, a broad range of alcohols, including primary and secondary benzylic alcohols as well as aliphatic alcohols, were readily oxidized to carbonyls in moderate to excellent yields. A site-selective oxidation has also been achieved by this protocol. Mechanistic investigation indicates that the oxidation proceeds through an oxidative radical-polar crossover process to obtain an α-oxy carbon cation.

10.
Ann Med ; 55(1): 2227844, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37354023

RESUMEN

BACKGROUND: Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are widely used for industrial and commercial purposes and have received increasing attention due to their adverse effects on health. OBJECTIVE: To examine the relationship of serum PFAS and glycometabolism among adolescents based on the US National Health and Nutrition Examination Survey. METHODS: General linear regression models were applied to estimate the relationship between exposure to single PFAS and glycometabolism. Weighted quantile sum (WQS) regression models and Bayesian kernel machine regressions (BKMR) were used to assess the associations between multiple PFASs mixture exposure and glycometabolism. RESULTS: A total of 757 adolescents were enrolled. Multivariable regression model showed that Me-PFOSA-AcOH exposure was negatively associated with fasting blood glucose. WQS index showed that there was marginal negative correlation between multiple PFASs joint exposure and the homeostasis model of assessment for insulin resistance index (HOMA-IR) (ß = -0.26, p < .068), and PFHxS had the largest weight. BKMR models showed that PFASs mixture exposure were associated with decreased INS and HOMA-IR, and the exposure-response relationship had curvilinear shape. CONCLUSIONS: The increase in serum PFASs were associated with a decrease in HOMA-IR among adolescents. Mixed exposure models could more accurately and effectively reveal true exposure.Key MessagesThe detection rates of different PFAS contents in adolescent serum remained diverse.Adolescent serum PFASs had negative curvilinear correlation with INS and HOMA-IR levels.PFHxS had the highest weight in the associations between multiple PFASs and adolescent glycometabolism.


Asunto(s)
Contaminantes Ambientales , Fluorocarburos , Humanos , Adolescente , Contaminantes Ambientales/efectos adversos , Contaminantes Ambientales/análisis , Encuestas Nutricionales , Teorema de Bayes , Fluorocarburos/efectos adversos , Insulina
11.
Physiol Plant ; 175(2): e13908, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37022777

RESUMEN

Wucai (Brassica campestris L. ssp. chinensis var. rosularis Tsen) belongs to the Brassica genus of the Cruciferae family, and its leaf curl is a typical feature that distinguishes Wucai from other nonheading cabbage subspecies. Our previous research found that plant hormones were involved in the development of the leaf curl in Wucai. However, the molecular mechanisms and the hormones regulating the formation of leaf curl in Wucai have not yet been reported. This study aimed to understand the molecular functions related to hormone metabolism during the formation of leaf curl in Wucai. A total of 386 differentially expressed genes (DEGs) were identified by transcriptome sequencing of two different morphological parts of the same leaf of Wucai germplasm W7-2, and 50 DEGs were found to be related to plant hormones, which were mainly involved in the auxin signal transduction pathway. Then, we measured the content of endogenous hormones in two different forms of the same leaf of Wucai germplasm W7-2. A total of 17 hormones with differential content were identified, including auxin, cytokinins, jasmonic acids, salicylic acids, and abscisic acid. And we found that treatment with auxin transport inhibitor N-1-naphthylphthalamic acid can affect the leaf curl phenotype of Wucai and pak choi (Brassica rapa L. subsp. Chinensis). These results indicated that plant hormones, especially auxin, are involved in developing the leaf curl of Wucai. Our findings provide a potentially valuable reference for future research on the development of leaf curls.


Asunto(s)
Brassica , Brassica/genética , Ácidos Indolacéticos/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Hormonas/metabolismo , Regulación de la Expresión Génica de las Plantas
12.
J Appl Stat ; 50(2): 370-386, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36698547

RESUMEN

This work proposes a two-stage procedure for identifying outlying observations in a large-dimensional data set. In the first stage, an outlier identification measure is defined by using a max-normal statistic and a clean subset that contains non-outliers is obtained. The identification of outliers can be deemed as a multiple hypothesis testing problem, then, in the second stage, we explore the asymptotic distribution of the proposed measure, and obtain the threshold of the outlying observations. Furthermore, in order to improve the identification power and better control the misjudgment rate, a one-step refined algorithm is proposed. Simulation results and two real data analysis examples show that, compared with other methods, the proposed procedure has great advantages in identifying outliers in various data situations.

13.
J Hazard Mater ; 442: 130138, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36303360

RESUMEN

Exogenous microparticles including microplastics are novel pollutants that could persist in the environment with potential health effects, while crucial data on their exposure in humans are still lacking. To understand the panorama of microparticles including microplastics exposure and distribution characteristics in different kinds of body fluids. A non-targeted microparticle internal exposure landscape analysis was done in thirteen kinds of human enclosed body fluids covering eight body systems. Totally 104 patients aged 24-96 years with an average age of 56 years were included in this study. After sample digestion, non-soluble microparticles were detected and identified with one Raman Microspectroscope under a strict quality control-particle detection system. Totally 702 microparticles with size ranging from 2.15 to 103.27 µm were detected in samples. Microparticles were identified into 84 substances or 66 molecules, most of which were firstly reported inside human body. Nine kinds of microplastics were originally reported in human body fluids with their size ranging from 19.66 to 103.27 µm. Microparticles exposure was unexpectedly high inside the human body despite the protection of biological barriers and membranes, raising awareness of the impact of particle pollution on sustainable development.


Asunto(s)
Líquidos Corporales , Contaminantes Químicos del Agua , Humanos , Persona de Mediana Edad , Microplásticos , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Ambiental , Líquidos Corporales/química , Monitoreo del Ambiente
14.
Sci Bull (Beijing) ; 67(10): 1062-1076, 2022 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-36546250

RESUMEN

Transient receptor potential vanilloid1 (TRPV1) channel plays an important role in a wide range of physiological and pathological processes, and a comprehensive understanding of TRPV1 gating will create opportunities for therapeutic intervention. Recent incredible advances in cryo-electron microscopy (cryo-EM) have yielded high-resolution structures of all TRPV subtypes (TRPV1-6) and all of them share highly conserved six transmembrane (TM) domains (S1-S6). As revealed by the open structures of TRPV1 in the presence of a bound vanilloid agonist (capsaicin or resiniferatoxin), TM helicesS1 to S4 form a bundle that remains quiescent during channel activation, highlighting differences in the gating mechanism of TRPV1 and voltage-gated ion channels. Here, however, we argue that the structural dynamics rather than quiescence of S1-S4 domains is necessary for capsaicin-mediated activation of TRPV1. Using fluorescent unnatural amino acid (flUAA) incorporation and voltage-clamp fluorometry (VCF) analysis, we directly observed allostery of the S1-S4 bundle upon capsaicin binding. Covalent occupation of VCF-identified sites, single-channel recording, cell apoptosis analysis, and exploration of the role of PSFL828, a novel non-vanilloid agonist we identified, have collectively confirmed the essential role of this coordinated S1-S4 motility in capsaicin-mediated activation of TRPV1. This study concludes that, in contrast to cryo-EM structural studies, vanilloid agonists are also required for S1-S4 movement during TRPV1 activation. Redefining the gating process of vanilloid agonists and the discovery of new non-vanilloid agonists will allow the evaluation of new strategies aimed at the development of TRPV1 modulators.


Asunto(s)
Canales de Potencial de Receptor Transitorio , Canales de Potencial de Receptor Transitorio/metabolismo , Capsaicina/farmacología , Canales Catiónicos TRPV/agonistas , Microscopía por Crioelectrón , Dominios Proteicos
15.
Front Mol Biosci ; 9: 925404, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36052166

RESUMEN

Morphine, the most widely used analgesic, relieves severe pain by activating the µ-opioid receptor (MOR), whereas naloxone, with only slight structural changes compared to morphine, exhibits inhibitory effect, and is used to treat opioid abuse. The mechanism by which the MOR distinguishes between the two is unclear. Molecular dynamics (MD) simulations on a 1-µs time scale and metadynamics-enhanced conformational sampling are used here to determine the different interactions of these two ligands with MOR: morphine adjusted its pose by continuously flipping deeper into the pocket, whereas naloxone failed to penetrate deeper because its allyl group conflicts with several residues of MOR. The endogenous peptide ligand endomorphin-1 (EM-1) underwent almost no significant conformational changes during the MD simulations. To validate these processes, we employed GIRK4S143T, a MOR-activated Gßγ-protein effector, in combination with mutagenesis and electrophysiological recordings. We verified the role of some key residues in the dynamic recognition of naloxone and morphine and identified the key residue I322, which leads to differential recognition of morphine and naloxone while assisting EM-1 in activating MOR. Reducing the side chain size of I322 (MORI322A) transformed naloxone from an inhibitor directly into an agonist of MOR, and I322A also significantly attenuated the potency of MOR on EM-1, confirming that binding deep in the pocket is critical for the agonistic effect of MOR. This finding reveals a dynamic mechanism for the response of MOR to different ligands and provides a basis for the discovery of new ligands for MOR at the atomic level.

16.
ACS Appl Mater Interfaces ; 14(39): 44704-44712, 2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36148982

RESUMEN

Three-dimensional thermoelectric (TE) textiles (TETs) fabricated with TE filaments (TEFs) possess merits over other types such as thickness-direction thermal energy harvesting and excellent conformability with dynamic body curves, revealing the prospect of generating electricity for on-body application. Nonetheless, there is still a lack of a costless but scalable method to automatically and seamlessly produce in-series interconnected p-n segmented TEFs with high TE properties via conventional fiber spinning processes. Here, we developed an alternate wet-spinning strategy to continuously manufacture single-walled carbon nanotube-based p-n segmented TEFs at large scale. The TEF with high electrical conductivity (400-800 S cm-1) displays a low contact resistivity of 189.8 µΩ cm2 between the segments and interelectrode, showing 2 orders of magnitude smaller than that reported in the literature. More importantly, the power factors of p-type and n-type segments are 26.25 and 17.14 µW m-1 K-2, respectively, which are 3 and 4 orders of magnitude higher than those of advanced studies. We finally embroidered it into spacer fabric to fabricate a wearable TET, demonstrating an output power density of 501 nW m-2 at ΔT = 27.7 K. The methodology can inspire the development of fiber-based electronics such as wearable TEs and diodes and so forth.

17.
Ecotoxicol Environ Saf ; 245: 114105, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36155338

RESUMEN

Microplastics (MPs) pollution becomes an increasing concern and researchers keep exploring the health effects caused by MPs exposure. The ageing process in the environment significantly alters the physicochemical characteristics of MPs and subsequently affects their toxicities. The health effects of aged MPs exposure and the mechanism underlying are worthy of exploration. Polystyrene microplastics (PS-MPs) (with size less than 50 µm) were obtained by grinding and screening polystyrene materials. PS-MPs continued to be aged by ozone treatment (0.4 mg/min, 9 h). Both male and female C57BL/6 mice were orally exposed to 0 or 2 mg/kg/d aged PS-MPs for 28 days. Results showed that PS-MPs were found in liver, ovary and spleen of females and liver, testis and spleen of males in the aged PS-MPs group. Exposure to aged PS-MPs significantly decreased abdominal fat/body coefficient, the adipocyte size and the serum LDL-C level in females. Compared to the control, serum estradiol (E2) level, the mRNA expression levels of genes regulating E2 production (17ß-hsd, 3ß-hsd and Star) in ovary and the protein expression levels of E2 receptors (ERα, ERß), AMPKα and p-AMPKα1 in liver increased significantly, and the mRNA expression levels of AMP-activated protein kinase (AMPK) downstream genes (Srebp-1c, Fas and Scd1) in liver decreased significantly in the female aged PS-MPs group. Liver metabolomic profiling showed that differential metabolites between female aged PS-MPs group and female control group were enriched in biotin metabolism and the level of biotin increased significantly in the female aged PS-MPs group. However, no significant changes were detected in males. These results indicated that aged PS-MPs exposure increased ovarian E2 production and activated the AMPK pathway in the liver which might inhibit liver lipid synthesis only in females. Our findings provide new insights into the potential sex-specific health effects of environmental MPs pollution.


Asunto(s)
Microplásticos , Ozono , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Biotina , LDL-Colesterol/metabolismo , Estradiol/metabolismo , Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , Femenino , Metabolismo de los Lípidos , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Microplásticos/toxicidad , Ozono/metabolismo , Plásticos/metabolismo , Poliestirenos/metabolismo , Poliestirenos/toxicidad , ARN Mensajero/metabolismo , Factores Sexuales , Proteína 1 de Unión a los Elementos Reguladores de Esteroles
18.
Biomed Res Int ; 2022: 4893859, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35937403

RESUMEN

Evodia rutaecarpa has multiple pharmacological effects and is widely used in the prevention and treatment of migraine, diabetes, cardiovascular disease, cancer, and other chronic diseases; however, the pharmacological effects of its active compound evodiamine (Evo) have not been thoroughly investigated. The purpose of this study was to investigate the effects of Evo on antiplatelet activation and thrombosis. We discovered that Evo effectively inhibited collagen-induced platelet activation but had no effect on platelet aggregation caused by activators such as thrombin, ADP, and U46619. Second, we found that Evo effectively inhibited the release of platelet granules induced by collagen. Finally, evodiamine inhibits the transduction of the SFKs/Syk/Akt/PLCγ2 activation pathway in platelets. According to in vivo studies, Evo significantly prolonged the mesenteric thromboembolism induced by ferric chloride and had no discernible effect on the coagulation function of mice. In conclusion, the antiplatelet and thrombotic effects of Evo discovered in this study provide an experimental basis for the investigation of the pharmacological mechanisms of Evo and the development of antiplatelet drugs.


Asunto(s)
Activación Plaquetaria , Trombosis , Animales , Plaquetas/metabolismo , Colágeno/metabolismo , Ratones , Agregación Plaquetaria , Inhibidores de Agregación Plaquetaria/farmacología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Quinazolinas , Trombosis/etiología
19.
J Environ Public Health ; 2022: 4133245, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35990541

RESUMEN

Researching the relationship between urban agricultural nonpoint source pollution (UANSP) and increases in rural residents' income levels has significant practical implications for effectively controlling UANSP and improving the quality of life of urban residents, and it is conducive to achieving a win-win situation between economic and environmental benefits. This study chooses agricultural statistical data from Shanghai from 1998 to 2019, implements the EKC and the VAR model to dynamically analyze internal interaction between them, and thoroughly examines impact effect and explanatory contribution degree of each variable. The results show the following: (1) There was an inverted "N" curve between plastic film application intensity and rural residents' per capita disposable income; there was a linear decreasing relationship between the intensity of fertilizer and pesticide application and rural residents' per capita disposable income. (2) Nonpoint source pollution emissions will decrease as rural residents' income levels rise. Reduction of nonpoint source pollution can promote the short-term improvement of rural residents' income levels, but it has a negative effect on the long-term improvement of rural residents' income levels. (3) Fertilizer and pesticide application intensity had a low driving effect on rural residents' income growth, whereas plastic film application intensity had a strong driving effect. Therefore, the ANSP of Shanghai should be treated from both long-term and short-term perspectives on the basis of decreasing stage. In the long term, the government should increase farmers' sense of ownership in agricultural nonpoint source pollution control, prioritize the development of ecological circular agriculture, and gradually improve nonpoint source remote sensing monitoring and service management capabilities. In the short term, the government should reduce farmers' nonpoint source pollution through subsidies and technical assistance. To keep costs down, the government established an administrative reward and punishment system to control ANSP at the source.


Asunto(s)
Contaminación Difusa , Plaguicidas , Agricultura , China , Fertilizantes , Humanos , Plásticos , Calidad de Vida
20.
Proc Natl Acad Sci U S A ; 119(27): e2202669119, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35763576

RESUMEN

Induction of a pluripotent cell mass, called callus, from detached organs is an initial step in in vitro plant regeneration, during which phytohormone auxin-induced ectopic activation of a root developmental program has been shown to be required for subsequent de novo regeneration of shoots and roots. However, whether other signals are involved in governing callus formation, and thus plant regeneration capability, remains largely unclear. Here, we report that the Arabidopsis calcium (Ca2+) signaling module CALMODULIN IQ-MOTIF CONTAINING PROTEIN (CaM-IQM) interacts with auxin signaling to regulate callus and lateral root formation. We show that disruption of IQMs or CaMs retards auxin-induced callus and lateral root formation by dampening auxin responsiveness, and that CaM-IQM complexes physically interact with the auxin signaling repressors INDOLE-3-ACETIC ACID INDUCIBLE (IAA) proteins in a Ca2+-dependent manner. We further provide evidence that the physical interaction of CaM6 with IAA19 destabilizes the repressive interaction of IAA19 with AUXIN RESPONSE FACTOR 7 (ARF7), and thus regulates auxin-induced callus formation. These findings not only define a critical role of CaM-IQM-mediated Ca2+ signaling in callus and lateral root formation, but also provide insight into the interplay of Ca2+ signaling and auxin actions during plant regeneration and development.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Señalización del Calcio , Organogénesis de las Plantas , Raíces de Plantas , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Calmodulina/metabolismo , Ácidos Indolacéticos/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Factores de Transcripción/metabolismo
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