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1.
Neural Regen Res ; 20(2): 533-547, 2025 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38819065

RESUMO

JOURNAL/nrgr/04.03/01300535-202502000-00030/figure1/v/2024-05-28T214302Z/r/image-tiff In patients with Alzheimer's disease, gamma-glutamyl transferase 5 (GGT5) expression has been observed to be downregulated in cerebrovascular endothelial cells. However, the functional role of GGT5 in the development of Alzheimer's disease remains unclear. This study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer's disease, as well as the underlying mechanism. We observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer's disease (Aß1-42-treated hCMEC/D3 and bEnd.3 cells), as well as in the APP/PS1 mouse model. Additionally, injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive deficits. Interestingly, increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-ß in the brains of APP/PS1 mice. This effect may be attributable to inhibition of the expression of ß-site APP cleaving enzyme 1, which is mediated by nuclear factor-kappa B. Our findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer's disease pathogenesis, and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 mice. These findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer's disease.

2.
Environ Int ; 190: 108843, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38972117

RESUMO

BACKGROUND: Greenspaces contribute positively to mental and physical well-being, promote social cohesion, and alleviate environmental stressors, such as air pollution. Ecological studies suggest that greenspace may affect incidence and severity of Coronavirus Disease 2019 (COVID-19). OBJECTIVE: This study examines the association between residential greenspace and COVID-19 related hospitalization and death. METHOD: In this retrospective cohort based on patient records from the Greater Manchester Care Records, all first COVID-19 cases diagnosed between March 1, 2020, and May 31, 2022 were followed until COVID-19 related hospitalization or death within 28 days. Residential greenspace availability was assessed using the Normalized Difference Vegetation Index per lower super output area in Greater Manchester. The association of greenspace with COVID-19 hospitalization and mortality were estimated using multivariate logistic regression models after adjusting for potential individual, temporal, and spatial confounders. We explored potential effect modifications of the associations with greenspace and COVID-19 severity by age, sex, body mass index, smoking, deprivation, and certain comorbidities. Combined effects of greenspace and air pollution (NO2 and PM2.5) were investigated by mutually adjusting pairs with correlation coefficients ≤ 0·7. RESULTS: Significant negative associations were observed between greenspace availability and COVID-19 hospitalization and mortality with odds ratios [OR] (95 % Confidence Intervals [CI]) of 0·96 (0·94-0·97) and 0·84 (0·80-0·88) (per interquartile range [IQR]), respectively. These were significantly modified by deprivation (P-value for interaction < 0.05), showing that those most deprived obtained largest benefits from greenspace. Inclusion of NO2 and PM2.5 diminished associations to null for COVID-19 hospitalization, but only reduced them slightly for mortality, where inverse associations remained. CONCLUSION: In the Greater Manchester area, residential greenspace is associated with reduced risk of hospitalization or death in individuals with COVID-19, with deprived groups obtaining the greatest benefits. Associations were strongest for COVID-19 mortality, which were robust to inclusion of air pollutants in the models.

3.
Alzheimers Dement ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39015037

RESUMO

INTRODUCTION: Aging is one of the risk factors for the early onset of Alzheimer's disease (AD). We previously discovered that the age-dependent increase in Ubiquitin Conjugating Enzyme E2 N (UBE2N) plays a role in the accumulation of misfolded proteins through K63 ubiquitination, which has been linked to AD pathogenesis. However, the impact of UBE2N on amyloid pathology and clearance has remained unknown. RESULTS: We observed the elevated UBE2N during the amyloid beta (Aß) generation in the brains of 5×FAD, APP/PS1 mice, and patients with AD, in comparison to healthy individuals. UBE2N overexpression exacerbated amyloid deposition in 5×FAD mice and senescent monkeys, whereas knocking down UBE2N via CRISPR/Cas9 reduced Aß generation and cognitive deficiency. Moreover, pharmacological inhibition of UBE2N ameliorated Aß pathology and subsequent transcript defects in 5×FAD mice. DISCUSSION: We have discovered that age-dependent expression of UBE2N is a critical regulator of AD pathology. Our findings suggest that UBE2N could serve as a potential pharmacological target for the advancement of AD therapeutics. HIGHLIGHTS: Ubiquitin Conjugating Enzyme E2 N (UBE2N) level was elevated during amyloid beta (Aß) deposition in AD mouse and patients' brains. UBE2N exacerbated Aß generation in the AD mouse and senescent monkey. Drug inhibition of UBE2N ameliorated Aß pathology and cognitive deficiency.

5.
Environ Int ; 190: 108842, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38970980

RESUMO

BACKGROUND: Long-term exposure to road traffic noise is associated with cardiovascular disease, but the evidence on respiratory diseases is just emerging. We aimed to examine the association between long-term exposure to road traffic noise and the incidence of acute lower respiratory infections (ALRIs) in adults. METHODS: We followed 23,141 female nurses (age ≥ 44 years) from the Danish Nurse Cohort from baseline (1993 or 1999) to their first hospital contact (inpatient, outpatient, or emergency room) for ALRI, death, emigration or the end of 2015. The residential annual mean levels of road traffic noise (Lden) during the follow-up were estimated using the Nord2000 model. We applied time-varying Cox models to estimate the association of 3-year mean exposure to Lden with ALRIs incidence and piecewise analysis to estimate the threshold of Lden. We examined the robustness of the results by adjusting for residential exposure to air pollution, and the effect modification by attained age, socioeconomic status (SES), comorbidity, and lifestyle. RESULTS: During 18.5 years of follow-up, 2,004 nurses developed ALRIs. In a linear model, we detected a statistically significant positive association between Lden and ALRI, with a hazard ratio (HR) of 1.11 (95 % confidence interval (CI): 1.04, 1.17) per 9.2 dB (interquartile range, IQR). We observed non-linear association with a threshold at 57 dB, above which the HR was 1.25 (95 % CI: 1.09, 1.43) per IQR. Further adjustment for PM2.5 reduced the HRs slightly to 1.21 (95 % CI: 1.04, 1.40). The associations were stronger for nurses with asthma, and in those with lowest SES. CONCLUSION: We present novel findings in support of the association between long-term exposure to road traffic noise and ALRIs, independent of air pollution, suggesting noise as a risk factor for infectious respiratory diseases.

6.
J Hazard Mater ; 476: 135224, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39029187

RESUMO

Understanding the emission characteristics of particulate matter and associated heavy metals is essential for assessing their environmental and health impacts post-emission, as well as for identifying potential control technologies for the sources. Here, a field test was conducted at two advanced smelting plants equipped with comprehensive air pollution control devices. The particles emitted from different stages of lead and zinc smelting exhibited bi-modal size distributions, with peaks observed in PM0.1-1.0 and PM2.5-10, respectively. Particulate-bound Pb was identified as the predominant Pb species in the flue gas, primarily originating from ore crushing. Consequently, over 80 % of Pb was emitted in the form of coarse particles, a marked contrast to coal-fired power plants where Pb concentrated on fine particles. High efficiencies in Pb removal were achieved by dust collectors, flue gas purification systems, and acid plants with desulfurization systems, resulting in overall Pb emission factors in lead and zinc smelting were only 89.3 and 2.60 g t-1 (of metal production), respectively. Importantly, the contribution of gas-phase Pb, which accounts for approximately 16.6 % of total emissions, must not be neglected in future emission monitoring and control efforts.

7.
Bioresour Technol ; : 131123, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39029766

RESUMO

ε-Poly-L-lysine (ε-PL) is an amino acid homopolymer with diverse potential applications in the food, pharmaceutical and cosmetic industries. To improve its biomanufacturing efficiency, strain engineering and bioprocess optimization were combined in this study. Firstly, a cocktail strain breeding strategy was employed to generate a ε-PL high-production mutant, Streptomyces albulus GS114, with enhanced L-lysine uptake capability. Subsequently, the L-lysine feeding conditions during fed-batch fermentation were systematically optimized to improve the L-lysine supply, resulting in ε-PL production reaching 73.1 ±â€¯1.4 g/L in 5 L bioreactor. Finally, an engineered strain, S. albulus L2, with enhanced uptake capability and polymerization ability of L-lysine was constructed, achieving ε-PL production of 81.4 ±â€¯5.2 g/L by fed-batch fermentation. This represents the highest reported production of ε-PL to date. This study provided an efficient production strategy for ε-PL and valuable insights into the high-value utilization of L-lysine.

8.
Nano Lett ; 24(28): 8602-8608, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38954477

RESUMO

Currently, the construction of anti-ambipolar transistors (AATs) is primarily based on asymmetric heterostructures, which are challenging to fabricate. AATs used for photodetection are accompanied by dark currents that prove difficult to suppress, resulting in reduced sensitivity. This work presents light-triggered AATs based on an in-plane lateral WSe2 homojunction without van der Waals heterostructures. In this device, the WSe2 channel is partially electrically controlled by the back gate due to the screening effect of the bottom electrode, resulting in a homojunction that is dynamically modulated with gate voltage, exhibiting electrostatically reconfigurable and light-triggered anti-ambipolar behaviors. It exhibits high responsivity (188 A/W) and detectivity (8.94 × 1014 Jones) under 635 nm illumination with a low power density of 0.23 µW/cm2, promising a new approach to low-power, high-performance photodetectors. Moreover, the device demonstrates efficient self-driven photodetection. Furthermore, ternary inverters are realized using monolithic WSe2, simplifying the manufacturing of multivalued logic devices.

9.
Environ Epidemiol ; 8(4): e314, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39045486

RESUMO

Background: Air pollution health risk assessment (HRA) has been typically conducted for all causes and cause-specific mortality based on concentration-response functions (CRFs) from meta-analyses that synthesize the evidence on air pollution health effects. There is a need for a similar systematic approach for HRA for morbidity outcomes, which have often been omitted from HRA of air pollution, thus underestimating the full air pollution burden. We aimed to compile from the existing systematic reviews and meta-analyses CRFs for the incidence of several diseases that could be applied in HRA. To achieve this goal, we have developed a comprehensive strategy for the appraisal of the systematic reviews and meta-analyses that examine the relationship between long-term exposure to particulate matter with an aerodynamic diameter smaller than 2.5 µm (PM2.5), nitrogen dioxide (NO2), or ozone (O3) and incidence of various diseases. Methods: To establish the basis for our evaluation, we considered the causality determinations provided by the US Environmental Protection Agency Integrated Science Assessment for PM2.5, NO2, and O3. We developed a list of pollutant/outcome pairs based on these assessments and the evidence of a causal relationship between air pollutants and specific health outcomes. We conducted a comprehensive literature search using two databases and identified 75 relevant systematic reviews and meta-analyses for PM2.5 and NO2. We found no relevant reviews for long-term exposure to ozone. We evaluated the reliability of these studies using an adaptation of the AMSTAR 2 tool, which assesses various characteristics of the reviews, such as literature search, data extraction, statistical analysis, and bias evaluation. The tool's adaptation focused on issues relevant to studies on the health effects of air pollution. Based on our assessment, we selected reviews that could be credible sources of CRF for HRA. We also assessed the confidence in the findings of the selected systematic reviews and meta-analyses as the sources of CRF for HRA. We developed specific criteria for the evaluation, considering factors such as the number of included studies, their geographical distribution, heterogeneity of study results, the statistical significance and precision of the pooled risk estimate in the meta-analysis, and consistency with more recent studies. Based on our assessment, we classified the outcomes into three lists: list A (a reliable quantification of health effects is possible in an HRA), list B+ (HRA is possible, but there is greater uncertainty around the reliability of the CRF compared to those included on list A), and list B- (HRA is not recommended because of the substantial uncertainty of the CRF). Results: In our final evaluation, list A includes six CRFs for PM2.5 (asthma in children, chronic obstructive pulmonary disease, ischemic heart disease events, stroke, hypertension, and lung cancer) and three outcomes for NO2 (asthma in children and in adults, and acute lower respiratory infections in children). Three additional outcomes (diabetes, dementia, and autism spectrum disorders) for PM2.5 were included in list B+. Recommended CRFs are related to the incidence (onset) of the diseases. The International Classification of Diseases, 10th revision codes, age ranges, and suggested concentration ranges are also specified to ensure consistency and applicability in an HRA. No specific suggestions were given for ozone because of the lack of relevant systematic reviews. Conclusion: The suggestions formulated in this study, including CRFs selected from the available systematic reviews, can assist in conducting reliable HRAs and contribute to evidence-based decision-making in public health and environmental policy. Future research should continue to update and refine these suggestions as new evidence becomes available and methodologies evolve.

10.
Small ; : e2310316, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38895965

RESUMO

Following the diverse structural characteristics and primary usage, diamond products include nano-polycrystalline diamond (NPD), micron-polycrystalline diamond (MPD), diamond film, porous diamond, and diamond wire drawing die. Among them, porous diamond possesses a distinctive combination of flexible surface functionality and a remarkably high surface area-to-volume ratio (SA/V) compared to traditional bulk materials, which contributes to cross-cutting applications in catalysis, adsorption, and electrochemistry while retaining the superior traits of diamond, particularly its exceptional chemical inertia. To avoid etching or microwave plasma chemical vapor deposition (MPCVD) techniques, this study proposes a high-temperature and high-pressure method based on a soluble skeleton (HPHT-ss) as an efficient and inexpensive approach for synthesizing millimeter-level porous diamonds. Interestingly, porous diamond synthesized by HPHT-ss exhibits multiscale pores distributed as macropores (average 75 µm) and mesopores (average 19 nm), which gives it a unique feature compared with other methods. Pertinent temperature-pressure conditions, HPHT-ss synthesis, and the formation mechanism of porous diamonds are also thoroughly discussed.

11.
J Exp Clin Cancer Res ; 43(1): 173, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38898487

RESUMO

BACKGROUND: Though tamoxifen achieves success in treating estrogen receptor α (ERα)-positive breast cancer, the followed development of tamoxifen resistance is a common challenge in clinic. Signals downstream of prolactin receptor (PRLR) could synergize with ERα in breast cancer progression. However, the potential effect of targeting PRL-PRLR axis combined with tamoxifen has not been thoroughly investigated. METHODS: High-throughput RNA-seq data obtained from TCGA, Metabric and GEO datasets were analyzed to explore PRLR expression in breast cancer cell and the association of PRLR expression with tamoxifen treatment. Exogenous or PRL overexpression cell models were employed to investigate the role of activated PRLR pathway in mediating tamoxifen insensitivity. Immunotoxin targeting PRLR (N8-PE24) was constructed with splicing-intein technique, and the efficacy of N8-PE24 against breast cancer was evaluated using in vitro and in vivo methods, including analysis of cells growth or apoptosis, 3D spheroids culture, and animal xenografts. RESULTS: PRLR pathway activated by PRL could significantly decrease sensitivity of ERα-positive breast cancer cells to tamoxifen. Tamoxifen treatment upregulated transcription of PRLR and could induce significant accumulation of PRLR protein in breast cancer cells by alkalizing lysosomes. Meanwhile, tamoxifen-resistant MCF7 achieved by long-term tamoxifen pressure exhibited both upregulated transcription and protein level of PRLR. Immunotoxin N8-PE24 enhanced sensitivity of breast cancer cells to tamoxifen both in vitro and in vivo. In xenograft models, N8-PE24 significantly enhanced the efficacy of tamoxifen and paclitaxel when treating PRLR-positive triple-negative breast cancer. CONCLUSIONS: PRL-PRLR axis potentially associates with tamoxifen insensitivity in ERα-positive breast cancer cells. N8-PE24 could inhibit cell growth of the breast cancers and promote drug sensitivity of PRLR-positive breast cancer cells to tamoxifen and paclitaxel. Our study provides a new perspective for targeting PRLR to treat breast cancer.


Assuntos
Neoplasias da Mama , Imunotoxinas , Receptores da Prolactina , Tamoxifeno , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Animais , Receptores da Prolactina/metabolismo , Receptores da Prolactina/genética , Camundongos , Imunotoxinas/farmacologia , Imunotoxinas/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Proliferação de Células , Apoptose
12.
BMC Plant Biol ; 24(1): 555, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877393

RESUMO

BACKGROUND: Selenium is essential for livestock and human health. The traditional way of adding selenium to livestock diets has limitations, and there is a growing trend to provide livestock with a safe and efficient source of selenium through selenium-enriched pasture. Therefore, this study was conducted to investigate the effects of selenium enrichment on fermentation characteristics, selenium content, selenium morphology, microbial community and in vitro digestion of silage alfalfa by using unenriched (CK) and selenium-enriched (Se) alfalfa as raw material for silage. RESULTS: In this study, selenium enrichment significantly increased crude protein, soluble carbohydrate, total selenium, and organic selenium contents of alfalfa silage fresh and post-silage samples, and it significantly decreased neutral detergent fiber and acid detergent fiber contents (p < 0.05). Selenium enrichment altered the form of selenium in plants, mainly in the form of SeMet and SeMeCys, which were significantly higher than that of CK (p < 0.05). Selenium enrichment could significantly increase the lactic acid content, reduce the pH value, change the diversity of bacterial community, promote the growth of beneficial bacteria such as Lactiplantibacillus and inhibit the growth of harmful bacteria such as Pantoea, so as to improve the fermentation quality of silage. The in vitro digestibility of dry matter (IVDMD), in vitro digestibility of acid detergent fibers (IVADFD) and in vitro digestibility of acid detergent fibers (IVNDFD) of silage after selenium enrichment were significantly higher than those of CK (p < 0.05). CONCLUSION: This study showed that the presence of selenium could regulate the structure of the alfalfa silage bacterial community and improve alfalfa silage fermentation quality. Selenium enrichment measures can change the morphology of selenium in alfalfa silage products, thus promoting the conversion of organic selenium.


Assuntos
Fermentação , Medicago sativa , Microbiota , Selênio , Silagem , Medicago sativa/metabolismo , Silagem/análise , Selênio/metabolismo , Animais , Ração Animal/análise
13.
Biochem Biophys Res Commun ; 725: 150272, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-38901224

RESUMO

Ketamine, an N-methyl-d-aspartate (NMDA) receptor antagonist, induces deficits in cognition and information processing following chronic abuse. Adolescent ketamine misuse represents a significant global public health issue; however, the neurodevelopmental mechanisms underlying this phenomenon remain largely elusive. This study investigated the long-term effects of sub-chronic ketamine (Ket) administration on the medial prefrontal cortex (mPFC) and associated behaviors. In this study, Ket administration during early adolescence displayed a reduced density of excitatory synapses on parvalbumin (PV) neurons persisting into adulthood. However, the synaptic development of excitatory pyramidal neurons was not affected by ketamine administration. Furthermore, the adult Ket group exhibited hyperexcitability and impaired socialization and working memory compared to the saline (Sal) administration group. These results strongly suggest that sub-chronic ketamine administration during adolescence results in functional deficits that persist into adulthood. Bioinformatic analysis indicated that the gene co-expression module1 (M1) decreased expression after ketamine exposure, which is crucial for synapse development in inhibitory neurons during adolescence. Collectively, these findings demonstrate that sub-chronic ketamine administration irreversibly impairs synaptic development, offering insights into potential new therapeutic strategies.


Assuntos
Neurônios GABAérgicos , Interneurônios , Ketamina , Parvalbuminas , Córtex Pré-Frontal , Sinapses , Animais , Ketamina/farmacologia , Ketamina/administração & dosagem , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Parvalbuminas/metabolismo , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Masculino , Interneurônios/efeitos dos fármacos , Interneurônios/metabolismo , Camundongos , Neurônios GABAérgicos/efeitos dos fármacos , Neurônios GABAérgicos/metabolismo , Camundongos Endogâmicos C57BL , Antagonistas de Aminoácidos Excitatórios/farmacologia
14.
Light Sci Appl ; 13(1): 143, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38918396

RESUMO

Quantum heat engines and refrigerators are open quantum systems, whose dynamics can be well understood using a non-Hermitian formalism. A prominent feature of non-Hermiticity is the existence of exceptional points (EPs), which has no counterpart in closed quantum systems. It has been shown in classical systems that dynamical encirclement in the vicinity of an EP, whether the loop includes the EP or not, could lead to chiral mode conversion. Here, we show that this is valid also for quantum systems when dynamical encircling is performed in the vicinity of their Liouvillian EPs (LEPs), which include the effects of quantum jumps and associated noise-an important quantum feature not present in previous works. We demonstrate, using a Paul-trapped ultracold ion, the first chiral quantum heating and refrigeration by dynamically encircling a closed loop in the vicinity of an LEP. We witness the cycling direction to be associated with the chirality and heat release (absorption) of the quantum heat engine (quantum refrigerator). Our experiments have revealed that not only the adiabaticity breakdown but also the Landau-Zener-Stückelberg process play an essential role during dynamic encircling, resulting in chiral thermodynamic cycles. Our observations contribute to further understanding of chiral and topological features in non-Hermitian systems and pave a way to exploring the relation between chirality and quantum thermodynamics.

15.
Nanoscale ; 16(27): 13011-13018, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38912545

RESUMO

Electrocatalytic reduction of CO2 into multicarbon (C2+) products offers a promising pathway for CO2 utilization. However, achieving high selectivity towards multicarbon alcohols, such as ethanol, remains a challenge. In this work, we present a novel CuO nanoflower catalyst with engineered tip curvature, achieving remarkable selectivity and efficiency in the electroreduction of CO2 to ethanol. This catalyst exhibits an ethanol faradaic efficiency (FEethanol) of 47% and a formation rate of 320 µmol h-1 cm-2, with an overall C2+ product faradaic efficiency (FEC2+) reaching ∼77.8%. We attribute this performance to the catalyst's sharp tip, which generates a strong local electric field, thereby accelerating CO2 activation and facilitating C-C coupling for deep CO2 reduction. In situ Raman spectroscopy reveals an increased *OH coverage under operating conditions, where the enhanced *OH adsorption facilitates the stabilization of *CHCOH intermediates through hydrogen bonding interaction, thus improving ethanol selectivity. Our findings demonstrate the pivotal role of local electric fields in altering reaction kinetics for CO2 electroreduction, presenting a new avenue for catalyst design aiming at converting CO2 to ethanol.

16.
Colloids Surf B Biointerfaces ; 241: 113995, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38870647

RESUMO

The interaction between nucleotide molecules and lipid molecules plays important roles in cell activities, but the molecular mechanism is very elusive. In the present study, a small but noticeable interaction between the negatively charged phosphatidylethanolamine (PE) and Guanosine monophosphate (GMP) molecules was observed from the PE monolayer at the air/water interface. As shown by the sum frequency generation (SFG) spectra and Pi-A isotherm of the PE monolayer, the interaction between the PE and GMP molecules imposes very small changes to the PE molecules. However, the Brewster angle microscopy (BAM) technique revealed that the assembly conformations of PE molecules are significantly changed by the adsorption of GMP molecules. By comparing the SFG spectra of PE monolayers after the adsorption of GMP, guanosine and guanine, it is also shown that the hydrogen bonding effect plays an important role in the nucleotide-PE interactions. These results provide fundamental insight into the structure changes during the nucleotide-lipid interaction, which may shed light on the molecular mechanism of viral infection, DNA drug delivery, and cell membrane curvature control in the brain or neurons.

17.
Heliyon ; 10(11): e31578, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38841457

RESUMO

Optimizing the pattern of territorial space utilization is one of the key tasks to achieve the sustainable development goals. With the accelerating rate of global urbanization, the understanding of territorial space utilization efficiency, role and potential is a prerequisite for alleviating contradictions in urban and rural space distribution. The city cluster is the main form of organization for urban development in future, so the study attempted to explore the urban and rural space utilization efficiency (URSUE) in Chengdu-Chongqing urban agglomeration (CCEC) from coupling coordination degree (CCD) perspective. Considering the gradual increase in the trend of remote interactions between URSUE, we further introduced the Local and Tele-coupling coordination (LTCCD) model that takes into account interactive development relationship between different systems. The results of the study show that: In CCEC, the more economically developed cities indicated that urban spatial utilization efficiency lags behind rural spatial utilization efficiency; The LTCCD in the geographic center region will indicate a higher level but the LTCCD in the economic core cities is higher compared with their CCD level, especially in Chengdu City. This suggests that the LTCCD model is better able to take into account regional development correlations and spatial spillovers effect. This study attempts to explore several key issues of urban-rural spatial allocation in the process of urbanization development and to provide guidance for the territorial space utilization planning in urban agglomerations.

18.
Lab Chip ; 24(13): 3284-3293, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38847194

RESUMO

The prostate-specific antigen (PSA) test is considered an important way for preoperative diagnosis and accurate screening of prostate cancer. Current antigen detection methods, including radioimmunoassay, enzyme-linked immunosorbent assay and microfluidic electrochemical detection, feature expensive equipment, long testing time and poor stability. Here, we propose a portable biosensor composed of electrolyte-gated amorphous indium gallium zinc oxide (a-IGZO) transistors with an extended gate, which can achieve real-time, instant PSA detection at a low operating voltage (<2 V) owing to the liquid-free ionic conductive elastomer (ICE) serving as the gate dielectric. The electric double layer (EDL) capacitance in ICE enhances the accumulation of carriers in the IGZO channel, leading to strong gate modulation, which enables the IGZO transistor to have a small subthreshold swing (<0.5 V dec-1) and a high on-state current (∼4 × 10-4 A). The separate, biodegradable, and pluggable sensing pad, serving as an extended gate connected to the IGZO transistor, prevents contamination and depletion arising from direct contact with biomolecular buffers, enabling the IGZO transistor to maintain superior electronic performance for at least six months. The threshold voltage and channel current of the transistor exhibit excellent linear response to PSA molecule concentrations across five orders of magnitude ranging from 1 fg mL-1 to 10 pg mL-1, with a detection limit of 400 ag mL-1 and a detection time of ∼5.1 s. The fabricated biosensors offer a point-of-care system for antigen detection, attesting the feasibility of the electrolyte-gated transistors in clinical screening, healthcare diagnostics and biological management.


Assuntos
Técnicas Biossensoriais , Eletrólitos , Gálio , Antígeno Prostático Específico , Transistores Eletrônicos , Óxido de Zinco , Antígeno Prostático Específico/análise , Humanos , Eletrólitos/química , Óxido de Zinco/química , Técnicas Biossensoriais/instrumentação , Gálio/química , Masculino , Índio/química , Desenho de Equipamento
19.
Chemistry ; : e202402001, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38924189

RESUMO

Harvesting waste heat efficiently with thermoelectric energy conversion requires materials with low thermal conductivity. Recently, it was demonstrated how dynamic lone pair expression in thermoelectric InTe is responsible for giant anharmonicity leading to a very low lattice thermal conductivity. InTe also contains correlated disorder of intrinsic defects due to vacancies, and this contributes to additional lowering of the thermal conductivity. Here we use the three-dimensional difference pair distribution (3D-ΔPDF) to analyze 25 K single crystal diffuse X-ray scattering from InTe to unravel the local defect structure, and propose a microscopic structural model. Extended off-centering of In+ ions induced by vacancies allows for the local expression of stereochemically active lone pairs. The associated electronic stabilization is proposed to be a driving force for the formation of In+ vacancy defects in InTe.

20.
Nat Commun ; 15(1): 5316, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909037

RESUMO

Circumventing the conventional two-electron oxygen reduction pathway remains a great problem in enhancing the efficiency of H2O2 photosynthesis. A promising approach to achieve outstanding photocatalytic activity involves the utilization of redox intermediates. Here, we engineer a polyimide aerogel photocatalyst with photoreductive carbonyl groups for non-sacrificial H2O2 production. Under photoexcitation, carbonyl groups on the photocatalyst surface are reduced, forming an anion radical intermediate. The produced intermediate is oxidized by O2 to produce H2O2 and subsequently restores the carbonyl group. The high catalytic efficiency is ascribed to a photocatalytic redox cycle mediated by the radical anion, which not only promotes oxygen adsorption but also lowers the energy barrier of O2 reduction reaction for H2O2 generation. An apparent quantum yield of 14.28% at 420 ± 10 nm with a solar-to-chemical conversion efficiency of 0.92% is achieved. Moreover, we demonstrate that a mere 0.5 m2 self-supported polyimide aerogel exposed to natural sunlight for 6 h yields significant H2O2 production of 34.3 mmol m-2.

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