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1.
EMBO J ; 39(5): e102541, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-31975428

RESUMO

UHMK1 is a nuclear serine/threonine kinase recently implicated in carcinogenesis. However, the functions and action mechanisms of UHMK1 in the pathogenesis of human gastric cancer (GC) are unclear. Here, we observed that UHMK1 was markedly upregulated in GC. UHMK1 silencing strongly inhibited GC aggressiveness. Interestingly, UHMK1-induced GC progression was mediated primarily via enhancing de novo purine synthesis because inhibiting purine synthesis reversed the effects of UHMK1 overexpression. Mechanistically, UHMK1 activated ATF4, an important transcription factor in nucleotide synthesis, by phosphorylating NCOA3 at Ser (S) 1062 and Thr (T) 1067. This event significantly enhanced the binding of NCOA3 to ATF4 and the expression of purine metabolism-associated target genes. Conversely, deficient phosphorylation of NCOA3 at S1062/T1067 significantly abrogated the function of UHMK1 in GC development. Clinically, Helicobacter pylori and GC-associated UHMK1 mutation induced NCOA3-S1062/T1067 phosphorylation and enhanced the activity of ATF4 and UHMK1. Importantly, the level of UHMK1 was significantly correlated with the level of phospho-NCOA3 (S1062/T1067) in human GC specimens. Collectively, these results show that the UHMK1-activated de novo purine synthesis pathway significantly promotes GC development.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Coativador 3 de Receptor Nuclear/metabolismo , Nucleotídeos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Neoplasias Gástricas/genética , Animais , Linhagem Celular Tumoral , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Coativador 3 de Receptor Nuclear/genética , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Estômago/patologia , Neoplasias Gástricas/patologia , Regulação para Cima
2.
Small ; : e2311914, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566542

RESUMO

The high-performance hole transporting material (HTM) is one of the most important components for the perovskite solar cells (PSCs) in promoting power conversion efficiency (PCE). However, the low conductivity of HTMs and their additional requirements for doping and post-oxidation greatly limits the device performance. In this work, three novel pyrene-based derivatives containing methoxy-substituted triphenylamines units (PyTPA, PyTPA-OH and PyTPA-2OH) are designed and synthesized, where different numbers of hydroxyl groups are connected at the 2- or 2,7-positions of the pyrene core. These hydroxyl groups at the 2- or 2,7-positions of pyrene play a significantly role to enhance the intermolecular interactions that are able to generate in situ radicals with the assistance of visible light irradiation, resulting in enhanced hole transferring ability, as well as an enhanced conductivity and suppressed recombination. These pyrene-core based HTMs exhibit excellent performance in PSCs, which possess a higher PCE than those control devices using the traditional spiro-OMeTAD as the HTM. The best performance can be found in the devices with PyTPA-2OH. It has an average PCE of 23.44% (PCEmax = 23.50%), which is the highest PCE among the reported PSCs with the pyrene-core based HTMs up to date. This research offers a novel avenue to design a dopant-free HTM by the combination of the pyrene core, methoxy triphenylamines, and hydroxy groups.

3.
J Org Chem ; 89(3): 1681-1691, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38207100

RESUMO

Pyrene-based derivatives have been widely deployed in organic luminescent materials because of their bright fluorescence, high charge carrier mobility, and facile modification. Nevertheless, the fluorescence output of conventional pyrenes is prone to quenching upon aggregation due to extensive intermolecular π-π stacking interactions. To address this issue, a set of new Y-shaped pyrene-containing luminogens are synthesized from a new bromopyrene chemical precursor, 2-hydroxyl-7-tert-butyl-1,3-bromopyrene, where the bromo and hydroxyl groups at the pyrene core can be readily modified to obtain the target products and provide great flexibility in tuning the photophysical performances. When the hydroxy group at the 2-position of pyrene was replaced by a benzyl group, the steric hindrance of the benzyl group not only efficiently inhibits the detrimental intermolecular π-π stacking interactions but also rigidifies the molecular conformation, resulting in a narrow-band blue emission. Moreover, the TPE-containing compounds 2c and 3c possessed characteristic aggregation-induced emission (AIE) properties with fluorescence quantum yields of up to 66% and 38% in the solid state, respectively. Thus, this article has methodically investigated the factors influencing the optical behavior, such as intermolecular interactions, and the steric effects of the substituent group, thereby opening up the potential to develop narrow-band pyrene-based blue emitters for OLED device applications.

4.
J Org Chem ; 89(5): 3319-3330, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38362859

RESUMO

High-efficiency narrow-band luminescent materials have attracted intense interest, resulting in their great colorimetric purity. This has led to a variety of high-tech applications in high-definition displays, spectral analysis, and biomedicine. In this study, a rigid pyrene core was employed as the molecular backbone, and four narrow-band pyrene-based blue emitters were synthesized using various synthetic methods (such as Lewis-acid catalyzed cyclization domino reactions, Pd-catalyzed coupling reactions like Suzuki-Miyaura and Sonogashira). Due to the steric effect of the hydroxy group at the 2-position, the target compounds exhibit deep blue emission (<429 nm, CIEy < 0.08) with full width at half-maximum (FWHM) less than 33 nm both in solution and when solidified. The experimental and theoretical results indicated that the substituents at the 1- and 3-positions afford a large dihedral angle with the pyrene core, and the molecular motion is almost fixed by multiple intra- and intermolecular hydrogen bonding interactions in the crystallized state, leading to a suppression of the vibrational relaxation of the molecular structure. Moreover, we observed that the suppression of the vibrational relaxation in the molecular structures and the construction of rigid conjugated structures can help develop narrow-band organic light-emitting materials.

5.
Arch Virol ; 169(4): 73, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38472498

RESUMO

Enterovirus 71 (EV71) is a neurotropic enterovirus associated with hand, foot, and mouth disease (HFMD) fatalities. In this study, we investigated the impact of EV71 on plasmacytoid dendritic cells (pDCs) and CD4+ T cells. The results showed that pDCs were promptly activated, secreting interferon (IFN)-α and inducing CD4+ T cell proliferation and differentiation during early EV71 infection. This initiated adaptive immune responses and promoted proinflammatory cytokine production by CD4+ T cells. Over time, viral nucleic acids and proteins were synthesized in pDCs and CD4+ T cells. Concurrently, the cholinergic anti-inflammatory pathway (CAP) was activated, exhibiting an anti-inflammatory role. With constant viral stimulation, pDCs and CD4+ T cells showed reduced differentiation and cytokine secretion. Defects in pDCs were identified as a key factor in CD4+ T cell tolerance. CAP had a more significant regulatory effect on CD4+ T cells than on pDCs and was capable of inhibiting inflammation in these cells.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Humanos , Neuroimunomodulação , Regulação para Cima , Interferon-alfa/metabolismo , Diferenciação Celular , Infecções por Enterovirus/metabolismo , Linfócitos T CD4-Positivos , Células Dendríticas
6.
Exp Brain Res ; 242(2): 443-449, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38147087

RESUMO

The purpose of this study was to identify the target genes of tcon_00044595, elucidate its activation site, and provide novel insights into the pathogenesis and treatment of neonatal hypoxic-ischemic brain damage (HIBD). Through homologous blast analysis, we identified predicted target sequences in the neighboring regions of the long non-coding RNA (lncRNA) tcon_00044595, suggesting that limd1 is its target gene. Starbase was utilized to identify potential candidate microRNAs associated with the lncRNA. The interaction between the candidate microRNAs and limd1 was investigated and validated using various experimental methods including in vitro cell culture, cell transfection, dual fluorescence reporter detection system, and real-time PCR. Homology alignment analysis revealed that the lncRNA tcon_00044595 exhibited a 246 bp homologous sequence at the 3' end of the adjacent limd1 gene, with a conservation rate of 68%. Analysis conducted on Starbase online identified three potential microRNA candidates: miR-3471, miR-883a-5p, and miR-214-3p. Intracellular expression of the limd1 gene was significantly down-regulated upon transfection with miR-3471, while the other two microRNAs did not produce noticeable effects. Luciferase reporter assays identified two interaction sites (UTR-1, UTR-2) between miR-3471 and the limd1 3'UTR, with UTR-1 exhibiting a strong influence. Further CCK8 assay indicated a protective role of miR-3471 during low oxygen stroke in HIBD. The potential regulatory relationship between lncRNA (tcon_00044595), miR-3471, and the target gene limd1 suggests their involvement in the occurrence and development of HIBD, providing new insights for investigating the underlying mechanisms and exploring targeted therapeutic approaches for HIBD.


Assuntos
Hipóxia-Isquemia Encefálica , MicroRNAs , RNA Longo não Codificante , Humanos , Recém-Nascido , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , MicroRNAs/genética , Hipóxia-Isquemia Encefálica/genética , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/patologia , Apoptose , Oxigênio
7.
Nanotechnology ; 35(34)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38810605

RESUMO

To effectively detect faults in transmission lines, monitoring the operating status of these lines is imperative. However, providing power to monitoring devices for transmission line status presents a significant challenge. In this research, a hybrid energy harvesting approach based on micro thermoelectric generator (MTEG) and triboelectric nanogenerator (TENG) is proposed, and a theoretical model for MTEG-TENG hybrid energy harvesting is established. This study develops an integrated energy harvesting prototype, which incorporates oscillating-TENG (O-TENGs), MTEGs, and a power management control unit. This prototype not only harvests energy from the vibrations of transmission lines but also converts the lines thermal energy into electricity. The Experiment results show that the maximum open-circuit voltages of O-TENG and MTEG reach 80.3 V and 1.094 V, respectively. Compared to a single MTEG energy harvesting device, the prototype of the MTEG-TENG hybrid energy harvesting device demonstrates a 5.36% improvement in energy harvesting and battery charging performance. Consequently, this approach achieves self-powered monitoring with excellent stability and lower manufacturing costs. It provides an efficient and durable power approach for transmission line status monitoring devices.

8.
Acta Pharmacol Sin ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750074

RESUMO

Hypoxia-ischemia (HI) is one of the main causes of neonatal brain injury. Mitophagy has been implicated in the degradation of damaged mitochondria and cell survival following neonatal brain HI injury. Pleckstrin homology-like domain family A member 1 (PHLDA1) plays vital roles in the progression of various disorders including the regulation of oxidative stress, the immune responses and apoptosis. In the present study we investigated the role of PHLDA1 in HI-induced neuronal injury and further explored the mechanisms underlying PHLDA1-regulated mitophagy in vivo and in vitro. HI model was established in newborn rats by ligation of the left common carotid artery plus exposure to an oxygen-deficient chamber with 8% O2 and 92% N2. In vitro studies were conducted in primary hippocampal neurons subjected to oxygen and glucose deprivation/-reoxygenation (OGD/R). We showed that the expression of PHLDA1 was significantly upregulated in the hippocampus of HI newborn rats and in OGD/R-treated primary neurons. Knockdown of PHLDA1 in neonatal rats via lentiviral vector not only significantly ameliorated HI-induced hippocampal neuronal injury but also markedly improved long-term cognitive function outcomes, whereas overexpression of PHLDA1 in neonatal rats via lentiviral vector aggravated these outcomes. PHLDA1 knockdown in primary neurons significantly reversed the reduction of cell viability and increase in intracellular reactive oxygen species (ROS) levels, and attenuated OGD-induced mitochondrial dysfunction, whereas overexpression of PHLDA1 decreased these parameters. In OGD/R-treated primary hippocampal neurons, we revealed that PHLDA1 knockdown enhanced mitophagy by activating FUNDC1, which was abolished by FUNDC1 knockdown or pretreatment with mitophagy inhibitor Mdivi-1 (25 µM). Notably, pretreatment with Mdivi-1 or the knockdown of FUNDC1 not only increased brain infarct volume, but also abolished the neuroprotective effect of PHLDA1 knockdown in HI newborn rats. Together, these results demonstrate that PHLDA1 contributes to neonatal HI-induced brain injury via inhibition of FUNDC1-mediated neuronal mitophagy.

9.
Lipids Health Dis ; 23(1): 128, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685023

RESUMO

BACKGROUND: Sepsis-associated encephalopathy (SAE) refers to the widespread impairment of brain function caused by noncentral nervous system infection mediated by sepsis. Lipid peroxidation-induced ferroptosis contributes to the occurrence and course of SAE. This study aimed to investigate the relationship between neuronal injury and lipid peroxidation-induced ferroptosis in SAE. METHODS: Baseline data were collected from pediatric patients upon admission, and the expression levels of various markers related to lipid peroxidation and ferroptosis were monitored in the serum and peripheral blood mononuclear cells (PBMCs) of patients with SAE as well as SAE model mice. The hippocampal phosphatidylethanolamine-binding protein (PEBP)-1/15-lysine oxidase (LOX)/ glutathione peroxidase 4 (GPX4) pathway was assessed for its role on the inhibitory effect of ferroptosis in SAE treatment. RESULTS: The results showed elevated levels of S100 calcium-binding protein beta (S-100ß), glial fibrillary acidic protein, and malondialdehyde in the serum of SAE patients, while superoxide dismutase levels were reduced. Furthermore, analysis of PBMCs revealed increased transcription levels of PEBP1, LOX, and long-chain fatty acyl-CoA synthetase family member 4 (ACSL4) in SAE patients, while the transcription levels of GPX4 and cystine/glutamate transporter xCT (SLC7A11) were decreased. In comparison to the control group, the SAE mice exhibited increased expression of S-100ß and neuron-specific enolase (NSE) in the hippocampus, whereas the expression of S-100ß and NSE were reduced in deferoxamine (DFO) mice. Additionally, iron accumulation was observed in the hippocampus of SAE mice, while the iron ion levels were reduced in the DFO mice. Inhibition of ferroptosis alleviated the mitochondrial damage (as assessed by transmission electron microscopy, hippocampal mitochondrial ATP detection, and the JC-1 polymer-to-monomer ratio in the hippocampus) and the oxidative stress response induced by SAE as well as attenuated neuroinflammatory reactions. Further investigations revealed that the mechanism underlying the inhibitory effect of ferroptosis in SAE treatment is associated with the hippocampal PEBP-1/15-LOX/GPX4 pathway. CONCLUSION: These results offer potential therapeutic targets for the management of neuronal injury in SAE and valuable insights into the potential mechanisms of ferroptosis in neurological disorders.


Assuntos
Ferroptose , Hipocampo , Peroxidação de Lipídeos , Proteína de Ligação a Fosfatidiletanolamina , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Encefalopatia Associada a Sepse , Ferroptose/efeitos dos fármacos , Animais , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Humanos , Encefalopatia Associada a Sepse/tratamento farmacológico , Encefalopatia Associada a Sepse/metabolismo , Encefalopatia Associada a Sepse/patologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Masculino , Feminino , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Proteína de Ligação a Fosfatidiletanolamina/genética , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/patologia , Coenzima A Ligases/metabolismo , Coenzima A Ligases/genética , Coenzima A Ligases/antagonistas & inibidores , Inflamação/metabolismo , Inflamação/patologia , Inflamação/tratamento farmacológico , Sistema y+ de Transporte de Aminoácidos/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismo , Subunidade beta da Proteína Ligante de Cálcio S100/genética , Modelos Animais de Doenças , Pré-Escolar , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Criança , Proteína Glial Fibrilar Ácida/metabolismo , Proteína Glial Fibrilar Ácida/genética , Malondialdeído/metabolismo , Sepse/complicações , Sepse/metabolismo , Sepse/tratamento farmacológico , Lactente
10.
BMC Public Health ; 24(1): 1202, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689223

RESUMO

BACKGROUND: Adherence to antiparkinsonian drugs (APDs) is critical for patients with Parkinson's disease (PD), for which medication is the main therapeutic strategy. Previous studies have focused on specific disorders in a single system when assessing clinical factors affecting adherence to PD treatment, and no international comparative data are available on the medical costs for Chinese patients with PD. The present study aimed to evaluate medication adherence and its associated factors among Chinese patients with PD using a systematic approach and to explore the impact of adequate medication adherence on direct medical costs. METHODS: A retrospective analysis was conducted using the electronic medical records of patients with PD from a medical center in China. Patients with a minimum of two APD prescriptions from January 1, 2016 to August 15, 2018 were included. Medication possession ratio (MPR) and proportion of days covered were used to measure APD adherence. Multiple linear regression analysis was used to identify factors affecting APD adherence. Gamma regression analysis was used to explore the impact of APD adherence on direct medical costs. RESULTS: In total, 1,712 patients were included in the study, and the mean MPR was 0.68 (± 0.25). Increased number of APDs and all medications, and higher daily levodopa-equivalent doses resulted in higher MPR (mean difference [MD] = 0.04 [0.03-0.05]; MD = 0.02 [0.01-0.03]; MD = 0.03 [0.01-0.04], respectively); combined digestive system diseases, epilepsy, or older age resulted in lower MPR (MD = -0.06 [-0.09 to -0.03]; MD = -0.07 [-0.14 to -0.01]; MD = -0.02 [-0.03 to -0.01], respectively). Higher APD adherence resulted in higher direct medical costs, including APD and other outpatient costs. For a 0.3 increase in MPR, the two costs increased by $34.42 ($25.43-$43.41) and $14.63 ($4.86-$24.39) per year, respectively. CONCLUSIONS: APD adherence rate among Chinese patients with PD was moderate and related primarily to age, comorbidities, and healthcare costs. The factors should be considered when prescribing APDs.


Assuntos
Antiparkinsonianos , Registros Eletrônicos de Saúde , Adesão à Medicação , Doença de Parkinson , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/economia , Adesão à Medicação/estatística & dados numéricos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Registros Eletrônicos de Saúde/estatística & dados numéricos , China , Antiparkinsonianos/uso terapêutico , Antiparkinsonianos/economia , Custos de Cuidados de Saúde/estatística & dados numéricos
11.
Chem Soc Rev ; 52(19): 6715-6753, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37694728

RESUMO

Molecular aggregates are self-assembled from multiple molecules via weak intermolecular interactions, and new chemical and physical properties can emerge compared to their individual molecule. With the development of aggregate science, much research has focused on the study of the luminescence behaviour of aggregates rather than single molecules. Pyrene as a classical fluorophore has attracted great attention due to its diverse luminescence behavior depending on the solution state, molecular packing pattern as well as morphology, resulting in wide potential applications. For example, pyrene prefers to emit monomer emission in dilute solution but tends to form a dimer via π-π stacking in the aggregation state, resulting in red-shifted emission with quenched fluorescence and quantum yield. Over the past two decades, much effort has been devoted to developing novel pyrene-based fluorescent molecules and determining the luminescence mechanism for potential applications. Since the concept of "aggregation-induced emission (AIE)" was proposed by Tang et al. in 2001, aggregate science has been established, and the aggregated luminescence behaviour of pyrene-based materials has been extensively investigated. New pyrene-based emitters have been designed and synthesized not only to investigate the relationships between the molecular structure and properties and advanced applications but also to examine the effect of the aggregate morphology on their optical and electronic properties. Indeed, new aggregated pyrene-based molecules have emerged with unique properties, such as circularly polarized luminescence, excellent fluorescence and phosphorescence and electroluminescence, ultra-high mobility, etc. These properties are independent of their molecular constituents and allow for a number of cutting-edge technological applications, such as chemosensors, organic light-emitting diodes, organic field effect transistors, organic solar cells, Li-batteries, etc. Reviews published to-date have mainly concentrated on summarizing the molecular design and multi-functional applications of pyrene-based fluorophores, whereas the aggregation behaviour of pyrene-based luminescent materials has received very little attention. The majority of the multi-functional applications of pyrene molecules are not only closely related to their molecular structures, but also to the packing model they adopt in the aggregated state. In this review, we will summarize the intriguing optoelectronic properties of pyrene-based luminescent materials boosted by aggregation behaviour, and systematically establish the relationship between the molecular structure, aggregation states, and optoelectronic properties. This review will provide a new perspective for understanding the luminescence and electronic transition mechanism of pyrene-based materials and will facilitate further development of pyrene chemistry.

12.
Angew Chem Int Ed Engl ; : e202403597, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752455

RESUMO

Marine ladder polyethers have attracted the attention of chemists and biologists because of their potent biological activities. Synthetic chemists have attempted to construct their polyether frameworks by epoxide ring-opening cascades, as Nakanishi hypothesis describes. However, Baldwin's rules of ring closure state that exo-selective intramolecular cyclization of epoxy alcohols is preferred over endo-selective cyclization. Herein, we investigated epoxide ring-opening cascades of polyepoxy alcohols in [EMIM]BF4/PFTB (1-ethyl-3-methylimidazolium tetrafluoroborate /perfluoro-tert-butyl alcohol) and found that all-endo products were formed via epoxide-to-epoxonium ring-opening cyclizations (not restricted by Baldwin's rules, which only apply to intramolecular hydroxyl-to-epoxide cyclizations). We determined that the key factor enabling polyepoxy alcohols to undergo a high proportion of all-endo-selective cyclizations was inhibition of exo-selective hydroxyl-to-epoxide cyclization starting from the terminal hydroxyl group of a polyepoxy alcohol. By introducing a slow-release protecting group to the terminal hydroxyl group, we could markedly increase the cyclization yields of polyether fragments with hydrogen atoms at the ring junctions. For the first time, we constructed consecutively fused six-membered-ring and fused seven-, eight-, and nine-membered-ring polyether fragments by epoxide-to-epoxonium ring-opening cyclizations through the addition of a suitable Lewis acid. We also suggest that the biosynthesis of marine ladder polyethers may proceed via epoxide-to-epoxonium ring-opening cyclization of polyepoxide.

13.
Opt Lett ; 48(7): 1898-1901, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221794

RESUMO

Achromatic metalenses formed using previous design methods face a compromise between diameter, numerical aperture, and working wave band. To address this problem, the authors coat the refractive lens with a dispersive metasurface and numerically demonstrate a centimeter-scale hybrid metalens for the visible band of 440-700 nm. By revisiting the generalized Snell law, a universal design of a chromatic aberration correction metasurface is proposed for a plano-convex lens with arbitrary surface curvatures. A highly precise semi-vector method is also presented for large-scale metasurface simulation. Benefiting from this, the reported hybrid metalens is carefully evaluated and exhibits 81% chromatic aberration suppression, polarization insensitivity, and broadband imaging capacity.

14.
J Org Chem ; 88(19): 13520-13527, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37677077

RESUMO

Anions play an indispensable role in the balance and regulation of the ecological environment and human health; however, excess anions can cause serious ecological and environment problems. Therefore, the detection and removal of excess anions in aqueous solution is not only a technological problem but also crucial for environmental protection. Herein, a set of water-soluble pyrene-based cationic fluorophores were synthesized, which exhibit high sensitivity for the detection of the anions BF4-, PF6-, and ClO4- via electrostatic interactions. Such fluorescent probes exhibit "turn-on" emission characteristics even at low concentrations of anions due to anion-π+ interactions. Moreover, these fluorescence probes act as efficient precipitating agents for the removal of the BF4-, PF6-, and ClO4- anions from an aqueous environment. This work opens up new avenues for future research on pyrene-based fluorophores as turn-on fluorescence probes for anion detection and as excellent precipitating agents in environmental settings.

15.
J Pineal Res ; 75(1): e12885, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37183291

RESUMO

Hypoxia-ischemia (HI) of the brain not only impairs neurodevelopment but also causes pineal gland dysfunction, which leads to circadian rhythm disruption. However, the underlying mechanism of circadian rhythm disruption associated with HI-induced pineal dysfunction remains unknown. The zinc finger protein repressor protein with a predicted molecular mass of 58 kDa (RP58) is involved in the development and differentiation of nerve cells. In this study, we established an HI model in neonatal rats to investigate the expression of RP58 and its role in pineal dysfunction and circadian rhythm disruption induced by HI. We demonstrated that RP58 was highly expressed in the pineal gland under normal conditions and significantly downregulated in the pineal gland and primary pinealocytes following HI. Knockdown of RP58 decreased the expression of enzymes in the melatonin (Mel) synthesis pathway (tryptophan hydroxylase 1 [TPH1], acetylserotonin O-methyltransferase [ASMT], and arylalkylamine N-acetyltransferase [AANAT]) and clock genes (circadian locomotor output cycles kaput [CLOCK] and brain and muscle ARNT-like 1 [BMAL1]), and it also reduced the production of Mel, caused pineal cell injury, and disrupted circadian rhythms in vivo and in vitro. Similarly, HI reduced the expression of Mel synthesis enzymes (TPH1, ASMT, and AANAT) and clock genes (CLOCK and BMAL1), and caused pineal injury and circadian rhythm disruption, which were exacerbated by RP58 knockdown. The detrimental effect of RP58 knockdown on pineal dysfunction and circadian rhythm disruption was reversed by the addition of exogenous Mel. Furthermore, exogenous Mel reversed HI-induced pineal dysfunction and circadian rhythm disruption, as reflected by improvements in Mel production, voluntary activity periods, and activity frequency, as well as a diminished decrease in the expression of Mel synthesis enzymes and clock genes. The present study suggests that RP58 is an endogenous source of protection against pineal dysfunction and circadian rhythm disruption after neonatal HI.


Assuntos
Melatonina , Glândula Pineal , Ratos , Animais , Melatonina/metabolismo , Animais Recém-Nascidos , Fatores de Transcrição ARNTL/metabolismo , RNA Mensageiro/metabolismo , Ritmo Circadiano/fisiologia , Glândula Pineal/metabolismo , Hipóxia/metabolismo , Isquemia/metabolismo , Arilalquilamina N-Acetiltransferase/genética , Arilalquilamina N-Acetiltransferase/metabolismo
16.
BMC Pediatr ; 23(1): 7, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36597051

RESUMO

BACKGROUND: Left-to-right shunt congenital heart disease is more likely to induce recurrent respiratory infections in the patients which exacerbate pulmonary hypertension and thereby impairs cardiac function. It is urgent to explore a non-invasive and accurate diagnostic method that can show the cardiac anatomy and associated malformations in clinical research. OBJECTIVE: To determine the diagnostic value of peripheral mucin domain protein-3 (Tim-3), N-terminal pro-brain natriuretic peptide (NT proBNP), sestrin2 testing in patients with the left-to-right shunt congenital heart disease and heart failure. METHODS: Fifty-two neonates with with left to right shunt congenital heart disease and 30 healthy neonates were enrolled. Blood samples were collected within 24 h of admission from newborns for determining the content of TiM-3, NT proBNP, and Sestrin2. Analyzing the ROC curve provided insight into the diagnostic accuracy. Both a Spearman's rank correlation test and a logistic regression analysis were carried out. RESULTS: TiM-3, NT proBNP, and Sestrin2 levels in peripheral blood were statistically different in the three groups (P < 0.05). There were significant differences in LVEF and LVFS among the three groups (P < 0.05). When used to diagnose heart failure in conjunction with left-to-right shunt congenital heart disease, TiM-3, NT proBNP, and Sestrin2 exhibited sensitivity of 58.3, 58.3, and 83.3%, respectively, and specificity of 85.0, 72.5, and 70.0%. ROC curve analysis showed that the AUCs of Tim-3, NT proBNP, and sestrin2 in predicting the outcome of left-to-right shunted congenital heart disease combined with heart failure were 0.744 (95% CI, 0.580 to 0.908), 0.608 (95% CI, 0.359 to 0.857), respectively 0.744 (95% CI 0.592 to 0.896). CONCLUSION: Tim-3, NT proBNP, and sestrin2 can accurately differentiate heart failure from non-combined heart failure from left-to-right shunt congenital heart disease.


Assuntos
Cardiopatias Congênitas , Insuficiência Cardíaca , Humanos , Recém-Nascido , Receptor Celular 2 do Vírus da Hepatite A , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Peptídeo Natriurético Encefálico , Biomarcadores
17.
Luminescence ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053240

RESUMO

Three new pyrrolo[3,2-b]pyrrole derivatives containing methoxyphenyl, pyrene or tetraphenylethylene (TPE) units (compounds 1-3) have been designed, synthesized and fully characterized. The aggregation-induced emission (AIE) properties of compounds 1-3 were tested in different water fraction (fw ) of tetrahydrofuran (THF). The pyrrolo[3,2-b]pyrrole derivative 3 containing TPE units exhibited typical AIE features with an enhanced emission (∼32-fold) in the solid state versus in solution; compounds 1 and 2 exhibited an aggregation-caused quenching effect. In addition, the steric and electronic effects of the peripheral moieties on the emission behavior, both in solution and in the solid state, have been investigated. Moreover, pyrrolo[3,2-b]pyrrole 1 exhibits high sensitivity and selectivity for dichloromethane and chloroform solvents, with the system displaying a new emission peak and fast response time under ultraviolet irradiation.

18.
Matern Child Nutr ; 19(4): e13542, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37376961

RESUMO

To explore the effects of UNICEF-suggested modifiable factors, that is, water, sanitation and hygiene (WASH), early adequate feeding and health care on child malnutrition, and to examine the extent to which each factor contributes to urban-rural disparities of child malnutrition in China. Pooling two waves of regionally representative survey data from Jilin, China, in 2013 and 2018, we report on urban-rural relative risks (RRs) in the prevalence of child stunting, wasting and overweight. We employ Poisson regression to examine the effects of urban-rural setting and the three modifiable factors on the prevalence of each malnutrition outcome, that is, stunting, wasting and overweight. We perform mediation analyses to estimate the extent to which each modifiable factor could explain the urban-rural disparities in each malnutrition outcome. The prevalence of stunting, wasting and overweight were 10.9%, 6.3% and 24.7% in urban, and 27.9%, 8.2% and 35.9% in rural Jilin, respectively. The rural to urban crude RR was 2.55 (95% confidence interval [CI]: 1.92-3.39) for stunting, while the corresponding RRs for wasting and overweight were 1.31 (95% CI: 0.84-2.03) and 1.45 (95% CI: 1.20-1.76), respectively. The rural to urban RR for stunting reduced to 2.01 (95% CI: 1.44-2.79) after adjusting for WASH. The mediation analyses show that WASH could mediate 23.96% (95% CI: 4.34-43.58%) of the urban-rural disparities for stunting, while early adequate feeding and health care had no effects. To close the persistent urban-rural gap in child malnutrition, the specific context of rural China suggests that a multi-sectoral approach is warranted that focuses on the sanitation environment and other wider social determinants of health.


Assuntos
Transtornos da Nutrição Infantil , Desnutrição , Criança , Humanos , Lactente , Saneamento , Transtornos da Nutrição Infantil/epidemiologia , Água , Sobrepeso/epidemiologia , Desnutrição/epidemiologia , Transtornos do Crescimento/epidemiologia , Higiene , China/epidemiologia , Acessibilidade aos Serviços de Saúde
19.
J Am Chem Soc ; 144(29): 13163-13173, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35849786

RESUMO

Hydrogen production from water electrolysis in neutral-pH electrolytes can not only avoid the corrosion and safety issues and expand the catalyst option but also potentially integrate with artificial photosynthesis and bioelectrocatalysis. However, heterogeneous catalysts that can efficiently negotiate the sluggish oxygen evolution reaction (OER) in neutral solutions are considerably lacking. Herein, we report a template-assisted strategy for the synthesis of 13 kinds of tube-like nanostructured perovskite oxides (TNPOs) with markedly high Brunauer-Emmett-Teller surface areas. By systematic examination of these TNPOs, we found that the OER activity of TNPOs in neutral solution exhibits a volcano shape as a function of the covalency of transition metal-oxygen bonds. Consequently, our designed Sm-doped LaCoO3 catalyst yields a geometric current density of 8.5 mA cm-2 at 1.75 V versus the reversible hydrogen electrode in 1 M phosphate buffer solution (pH 7) due to the optimized covalency of Co 3d and O 2p states, representing the most active noble-metal-free OER catalyst in neutral electrolytes reported as yet.


Assuntos
Elementos de Transição , Água , Compostos de Cálcio , Hidrogênio , Óxidos , Oxigênio/química , Titânio
20.
Small ; 18(18): e2200445, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35373465

RESUMO

A photodetector based on 2D non-layered materials can easily utilize the photogating effect to achieve considerable photogain, but at the cost of response speed. Here, a rationally designed tunneling heterojunction fabricated by vertical stacking of non-layered In2 S3 and Te flakes is studied systematically. The Te/In2 S3 heterojunctions possess type-II band alignment and can transfer to type-I or type-III depending on the electric field applied, allowing for tunable tunneling of the photoinduced carriers. The Te/In2 S3 tunneling heterojunction exhibits a reverse rectification ratio exceeding 104 , an ultralow forward current of 10-12 A, and a current on/off ratio over 105 . A photodetector based on the heterojunctions shows an ultrahigh photoresponsivity of 146 A W-1 in the visible range. Furthermore, the devices exhibit a response time of 5 ms, which is two and four orders of magnitude faster than that of its constituent In2 S3 and Te. The simultaneously improved photocurrent and response speed are attributed to the direct tunneling of the photoinduced carriers, as well as a combined mechanism of photoconductive and photogating effects. In addition, the photodetector exhibits a clear photovoltaic effect, which can work in a self-powered mode.

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