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1.
Acta Pharm Sin B ; 14(8): 3362-3384, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39220863

RESUMO

Drug discovery is a sophisticated process that incorporates scientific innovations and cutting-edge technologies. Compared to traditional bioactivity-based screening methods, encoding and display technologies for combinatorial libraries have recently advanced from proof-of-principle experiments to promising tools for pharmaceutical hit discovery due to their high screening efficiency, throughput, and resource minimization. This review systematically summarizes the development history, typology, and prospective applications of encoding and displayed technologies, including phage display, ribosomal display, mRNA display, yeast cell display, one-bead one-compound, DNA-encoded, peptide nucleic acid-encoded, and new peptide-encoded technologies, and examples of preclinical and clinical translation. We discuss the progress of novel targeted therapeutic agents, covering a spectrum from small-molecule inhibitors and nonpeptidic macrocycles to linear, monocyclic, and bicyclic peptides, in addition to antibodies. We also address the pending challenges and future prospects of drug discovery, including the size of screening libraries, advantages and disadvantages of the technology, clinical translational potential, and market space. This review is intended to establish a comprehensive high-throughput drug discovery strategy for scientific researchers and clinical drug developers.

2.
Huan Jing Ke Xue ; 45(9): 5168-5178, 2024 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-39323135

RESUMO

To improve the phenomenon of the volatile organic compounds (VOCs) odor pollution nuisance in industrial parks and to promote the synergistic control of atmospheric VOCs and their odor-causing substances, based on the field observation of atmospheric VOCs in residential living areas and five different types of industrial clusters in industrial parks, we analyzed the pollution characteristics of atmospheric VOCs and their odor-causing volatile organic compounds (O-VOCs) in the residential living areas and each industrial cluster, evaluated the characteristics of the odor activity of the O-VOCs in the industrial parks, and identified the key odor-causing species and their main sources. The results showed that the mean values of atmospheric φ (TVOCs) and φ(O-VOCs) in the residential living area of the industrial park were 102.57×10-9 and 72.33×10-9, respectively. φ(TVOCs) and φ(O-VOCs) were significantly higher in the industrial clusters of basic chemical industry and pharmaceutics than in the other industrial clusters, and the sum (OAVsum) and maximum (OAVmax) of the odor activity values of these two clusters were relatively high, with a potential risk of odor nuisance. Overall, the O-VOCs species with higher odor intensity were similar in residential living areas and the five industrial clusters, and effective control of O-VOCs species such as acrolein, p-diethylbenzene, p-xylene, and 1,3-diethylbenzene is essential to mitigate or eliminate organic odor pollution. The results of the source apportionment of O-VOCs in the residential area showed that the sources of O-VOCs in the residential area were mainly influenced by natural gas chemical and pharmaceutics, and the coefficients of divergence (CDO-VOCs) between the O-VOC chemical profiles from residential areas and those from natural gas chemical and pharmaceutics were 0.31 and 0.38, respectively. Principal component analysis (PCA) also confirmed this result, with residential O-VOCs mainly originating from natural gas chemicals and pharmaceutics, followed by iron and steel manufacturing and automobile manufacturing, with the lowest contribution from the basic chemicals.

3.
Sci Total Environ ; 953: 176164, 2024 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-39260474

RESUMO

Nanoplastics are ubiquitous in marine environments, exhibiting high bioavailability and potential toxicity to marine organisms. However, the impacts of nanoplastics with various surface modifications on marine microalgae remain largely unexplored. This study explored the toxicity mechanisms of two nanoplastic types-polystyrene (PS) and polymethyl methacrylate (PMMA)-with distinct surface modifications on Skeletonema costatum at cellular and molecular levels. Results showed that nanoplastics significantly impaired the growth of microalgae, particularly PS-NH2, which caused the most pronounced growth inhibition, reaching 56.99 % after a 96-h exposure at 50 mg/L. Transcriptomic profiling revealed that nanoplastics disrupted the expression of genes predominantly involved in ribosome biogenesis, aminoacyl-tRNA biosynthesis, amino acid metabolism, and carbohydrate metabolism pathways. The integrated biochemical and transcriptomic evidence highlighted that PS-NH2 nanoplastics had the most adverse impact on microalgae, affecting fundamental pathways such as ribosome biogenesis, energy metabolism, photosynthesis, and oxidative stress. Our findings underscore the influence of surface-modified nanoplastics on algal growth and contribute new understanding to the toxicity mechanisms of these nanoplastics in marine microalgae, offering critical information for assessing the risks of emerging pollutants.


Assuntos
Microalgas , Poluentes Químicos da Água , Poluentes Químicos da Água/toxicidade , Microalgas/efeitos dos fármacos , Diatomáceas/efeitos dos fármacos , Microplásticos/toxicidade , Poliestirenos/toxicidade , Transcriptoma , Polimetil Metacrilato/toxicidade
4.
Adv Mater ; 36(40): e2407249, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39194637

RESUMO

The realization of spontaneous ferroelectricity down to the one-dimensional (1D) limit is both fundamentally intriguing and practically appealing for high-density ferroelectric and nonlinear photonics. However, the 1D vdW ferroelectric materials are not discovered experimentally yet. Here, the first 1D vdW ferroelectric compound NbOI3 with a high Curie temperature TC > 450 K and giant second harmonic generation (SHG) is reported. The 1D crystalline chain structure of the NbOI3 is revealed by cryo-electron microscopy, whereas the 1D ferroelectric order originated from the Nb displacement along the Nb-O chain (b-axis) is confirmed via obvious electrical and ferroelectric hysteresis loops. Impressively, NbOI3 exhibits a giant SHG susceptibility up to 1572 pm V-1 at a fundamental wavelength of 810 nm, and a further enhanced SHG susceptibility of 5582 pm V-1 under the applied hydrostatic pressure of 2.06 GPa. Combing in situ pressure-dependent X-ray diffraction, Raman spectra measurements, and first-principles calculations, it is demonstrated that the O atoms shift along the Nb─O atomic chain under compression, which can lead to the increased Baur distortion of [NbO2I4] octahedra, and hence induces the enhancement of SHG. This work provides a 1D vdW ferroelectric system for developing novel ferroelectronic and photonic devices.

5.
Toxicol Sci ; 202(1): 25-35, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39110510

RESUMO

Hyperoxia-induced acute lung injury (HALI) is a complication of oxygen therapy. Ferroptosis is a vital factor in HALI. This paper was anticipated to investigate the underlying mechanism of wedelolactone (WED) on ferroptosis in HALI. The current study used hyperoxia to injure two models, one HALI mouse model and one MLE-12 cell injury model. We found that WED treatment attenuated HALI by decreasing the lung injury score and lung wet/dry (W/D) weight ratio and alleviating pathomorphological changes. Then, the inflammatory reaction and apoptosis in HALI mice and hyperoxia-mediated MLE-12 cells were inhibited by WED treatment. Moreover, WED alleviated ferroptosis with less iron accumulation and reversed expression alterations of ferroptosis markers, including MDA, GSH, GPX4, SLC7A11, FTH1, and TFR1 in hyperoxia-induced MLE-12 cells in vitro and in vivo. Nrf2-KO mice and Nrf2 inhibitor (ML385) decreased WED's ability to protect against apoptosis, inflammatory response, and ferroptosis in hyperoxia-induced MLE-12 cells. Collectively, our data highlighted the alleviatory role of WED in HALI by activating the Nrf2/HO-1 pathway.


Assuntos
Lesão Pulmonar Aguda , Cumarínicos , Ferroptose , Hiperóxia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 2 Relacionado a NF-E2 , Transdução de Sinais , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Ferroptose/efeitos dos fármacos , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/prevenção & controle , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/tratamento farmacológico , Hiperóxia/complicações , Hiperóxia/metabolismo , Transdução de Sinais/efeitos dos fármacos , Masculino , Cumarínicos/farmacologia , Linhagem Celular , Camundongos , Heme Oxigenase-1/metabolismo , Heme Oxigenase (Desciclizante)/metabolismo , Heme Oxigenase (Desciclizante)/genética , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Modelos Animais de Doenças , Apoptose/efeitos dos fármacos , Proteínas de Membrana
6.
Orthop Surg ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39187981

RESUMO

OBJECTIVE: Lower limb discrepancy (LLD) was frequently observed in patients with idiopathic scoliosis (IS), potentially associated with etiopathogenesis. Although sole lifts had been proposed as a conservative treatment for IS, evidence supporting their efficacy was limited. This study aimed to assess the effects of sole lift intervention on pediatric patients with mild IS, specifically focusing on thoracolumbar/lumbar (TL/L) curvature. METHODS: Twenty patients, with an average age of 12.3 ± 3.1 years and presenting mild TL/L curve (15.6° ± 6.2°), were selected from a pool of 267 pediatric IS patients in the outpatient of our spine center from February 2023 to August 2023. Inclusion criteria comprised a main TL/L curve ranging between 10° and 40°, the lower limb positioned at the convexity of the main curve, and LLD of less than 2 cm; individuals requiring bracing or surgical intervention were excluded. Custom sole lifts were used to address the shorter lower limb with the objective of leveling the pelvis. Radiographic evaluations were conducted both before and after intervention using standing full spine posteroanterior radiographs and full leg length radiographs. Statistical analysis was undertaken to evaluate curve correction and its associations with other influencing factors. RESULTS: The mean structural and functional LLD were 7.1 ± 4.5 mm and 7.1 ± 4.1 mm, respectively. Among the 20 patients, four exhibited structural LLD greater than 10 mm. The average follow-up duration was 6.4 ± 1.9 months (range: 3-8 months). Following sole lift intervention (7.0 ± 3.0 mm), a significant reduction was observed in the TL/L curve compared to the pre-sole lifting measurements (15.6° ± 6.2° vs. 12.1° ± 7.2°, p < 0.001), as well as a notable decrease in the thoracic curve (12.2° ± 4.0° vs. 8.6° ± 6.3°, p = 0.064). Nine patients experienced a significant curve reduction of ≥5°, while eight showed a reduction between 0° and 5°; however, two patients exhibited no change in curve magnitude. Furthermore, the correction rate of the TL/L curve correlated significantly with functional LLD (r = -0.484, p = 0.030) and pelvic obliquity (r = -0.556, p = 0.011), highlighting the active pelvic compensation in maintaining balance between the spine and lower limbs. Conversely, no significant correlation was observed between curve correction and structural LLD (p > 0.05). Additionally, even after adjusting for other influencing factors, the TL/L Cobb angle remained significantly different between pre- and post-sole lifting (p = 0.037). CONCLUSION: This study confirmed the effectiveness of sole lift intervention in correcting TL/L and thoracic curves among the mild IS children with a main TL/L curve, providing a supplementary conservative treatment option for patients with the lower limb at the convexity of the main curve. Moreover, our findings underscored the active compensation of the lower limbs and the pelvis in the etiopathogenesis of IS, highlighting the importance of considering their influence in treatment strategies.

7.
Asian J Androl ; 26(5): 500-509, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39012524

RESUMO

ABSTRACT: Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is highly prevalent worldwide and poses a significant threat to men's health, particularly affecting young men. However, the exact causes and mechanisms behind CP/CPPS remain unclear, leading to challenges in its treatment. In this research, a CP/CPPS rat model was established with complete Freund's adjuvant (CFA), and berberine hydrochloride was administered through daily gavage to assess its therapeutic effects. The alterations in the gut microbiome induced by CP/CPPS and berberine hydrochloride were investigated through 16S ribosomal RNA sequencing of cecum content and colonic epithelial cells. To investigate the impact of the gut microbiome on CP/CPPS, a pseudo germ-free rat model was established, and fecal microbiome transplantation (FMT) was performed on these rats. In all, berberine hydrochloride demonstrated effective reduction of inflammation and oxidative stress in the prostate, offering significant therapeutic advantages for CP/CPPS. Through analysis of the gut microbiome using 16S ribosome RNA sequencing, distinct differences were observed between CP/CPPS rats and control rats, and Clostridium butyricum was identified as a key bacteria. Pseudo germ-free rats that underwent FMT from CP/CPPS rats or rats treated with berberine hydrochloride displayed varying levels of inflammatory cytokine production, oxidative stress, and activity of associated signaling pathways. In conclusion, the therapeutic potential of berberine hydrochloride in addressing CP/CPPS is highly significant. The gut microbiome has emerged as a critical factor in the development of CP/CPPS and plays a pivotal role in mediating the therapeutic effects of berberine hydrochloride.


Assuntos
Berberina , Microbioma Gastrointestinal , Prostatite , Ratos Sprague-Dawley , Transdução de Sinais , Berberina/farmacologia , Berberina/uso terapêutico , Masculino , Animais , Prostatite/microbiologia , Prostatite/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos , Dor Pélvica/tratamento farmacológico , Dor Pélvica/terapia , Transplante de Microbiota Fecal , Modelos Animais de Doenças , Estresse Oxidativo/efeitos dos fármacos , Dor Crônica/tratamento farmacológico , Próstata/efeitos dos fármacos , Próstata/microbiologia , RNA Ribossômico 16S/genética
8.
ACS Nano ; 18(25): 16274-16284, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38867607

RESUMO

Integration of atomically thin nonlinear optical (NLO) devices demands an out-of-plane (OP) emission dipole of second harmonic generation (SHG) to enhance the spontaneous emission for nanophotonics. However, the research on van der Waals (vdWs) materials with an OP emission dipole of SHG is still in its infancy. Here, by coupling back focal plane (BFP) imaging with numerical simulations and density functional theory (DFT) calculations, we demonstrate that vdWs Janus Nb3SeI7, ranging from bulk to the monolayer limit, exhibits a dominant OP emission dipole of SHG owing to the breaking of the OP symmetry. Explicitly, even-layered Nb3SeI7 with C6v symmetry is predicted to exhibit a pure OP emission dipole attributed to the only second-order susceptibility coefficient χzxx. Meanwhile, although odd-layered Nb3SeI7 with C3v symmetry has both OP and IP dipole components (χzxx and χyyy), the value of χzxx is 1 order of magnitude greater than that of χyyy, leading to an approximate OP emission dipole of SHG. Moreover, the crystal symmetry and OP emission dipole can be preserved under hydrostatic pressure, accompanied by the enhanced χzxx and the resulting 3-fold increase in SHG intensity. The reported stable OP dipole in 2D vdWs Nb3SeI7 can facilitate the rapid development of chip-integrated NLO devices.

9.
ACS Nano ; 18(26): 17053-17064, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38870206

RESUMO

Second harmonic generation (SHG) in van der Waals (vdW) materials has garnered significant attention due to its potential for integrated nonlinear optical and optoelectronic applications. Stacking faults in vdW materials are a typical kind of planar defect that introduces a degree of freedom to modulate the crystal symmetry and resultant SHG response. However, the physical origin and tunability of stacking-fault-governed SHG in vdW materials remain unclear. Here, taking the intrinsically centrosymmetric vdW RhI3 as an example, we theoretically reveal the origin of stacking-fault-governed SHG response, where the SHG response comes from the energetically favorable AC̅ stacking fault of which the electrical transitions along the high-symmetry paths Γ-M and Γ-K in the Brillion zone play the dominant role at 810 nm. Such a stacking-fault-governed SHG response is further confirmed via structural characterizations and SHG measurements. Furthermore, by applying hydrostatic pressure on RhI3, the correlation between structural evolution and SHG response is revealed with SHG enhancement up to 6.9 times, where the decreased electronic transition energies and higher momentum matrix elements due to the stronger interlayer interactions upon compression magnify the SHG susceptibility. This study develops a promising foundation for nonlinear nano-optics applications through the strategic design of stacking faults.

10.
Am J Cancer Res ; 14(5): 2072-2087, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38859866

RESUMO

Heat shock factor 1 (HSF1), an essential transcription factor for stress response, is exploited by various tumors to facilitate their initiation, progression, invasion, and migration. Amplification of HSF1 is widely regarded as an indicator in predicting cancer severity, the likelihood of treatment failure and reduced patient survival. Notably, HSF1 is markedly amplified in 40% of pancreatic cancer (PC), which typically have limited treatment options. HSF1 has been proven to be a promising therapeutic target for multiple cancers. However, a direct small molecule HSF1 inhibitor with sufficient bioactivity and reliable safety has not been developed clinically. In this study, we successfully established a high-throughput screening system utilizing luciferase reporter assay specifically designed for HSF1, which leads to the discovery of a potent small molecule inhibitor targeting HSF1. Homoharringtonine (HHT) selectively inhibited PC cell viability with high HSF1 expression and induced a markedly stronger tumor regression effect in the subcutaneous xenograft model than the comparator drug KRIBB11, known for its direct action on HSF1. Moreover, HHT shows promise in countering the resistance encountered with HSP90 inhibitors, which have been observed to increase heat shock response intensity in clinical trials. Mechanistically, HHT directly bound to HSF1, suppressing its expression and thereby inhibiting transcription of HSF1 target genes. In conclusion, our work presents a preclinical discovery and validation for HHT as a HSF1 inhibitor for PC treatment.

11.
ACS Nano ; 18(26): 17339-17348, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38905021

RESUMO

In recent years, two-dimensional (2D) transition metal dichalcogenides (TMDCs) have been widely recognized as an ideal platform for surface-enhanced Raman scattering (SERS). Given their rich structural phases, phase transformation in 2D TMDCs is an efficient strategy to tailor their SERS performance. In this paper, we present the great SERS performance of multilayer 2M-WS2 and then investigate the effect of its phase transformation on SERS performance. It is observed that multilayer 2M-WS2 nanosheets undergo a thermally induced single-crystal phase transition from 2M-WS2 to 2H-WS2 upon thermal annealing or laser treatment. Distinguishing from the commercially available pure 2H-WS2 (P-2H-WS2), 2H-WS2 obtained by annealing and laser treatment still retain SERS properties comparable to those of 2M-WS2, among which the detection limits for CV molecules (10-8 M) are 3 orders of magnitude lower than that of P-2H-WS2 and the Raman intensity enhancements are ∼10-37 times higher. In contrast to the charge transfer (CT) mechanism governed by the Fermi level in metallic-phase 2M-WS2, 2H-WS2 obtained by phase transition exhibits accelerated CT facilitated by the bandgap reduction and reorganization resulting from the abundance of vacancies. This study introduces an interesting perspective and potential avenue for enhancing SERS through metal-to-semiconductor phase transitions in 2D TMDCs materials.

12.
ACS Nano ; 18(13): 9636-9644, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38497667

RESUMO

A two-dimensional (2D) ferroelectric semiconductor, which is coupled with photosensitivity and room-temperature ferroelectricity, provides the possibility of coordinated conductance modulation by both electric field and light illumination and is promising for triggering the revolution of optoelectronics for monolithic multifunctional integration. Here, we report that semiconducting Sn2P2S6 crystals can be achieved in a 2D morphology using a chemical vapor transport approach with the assistant of space confinement and experimentally demonstrate the robust ferroelectricity in atomic-thin Sn2P2S6 nanosheet at room temperature. The intercorrelated programming of ferroelectric order along out-of-plane (OOP) and in-plane (IP) directions enables a tunable bulk photovoltaic (BPV) effect through multidirectional electrical control. By combining the capability of anisotropic in-plane optical absorption, a highly integrated Sn2P2S6 optoelectronic device vertically sandwiched with graphene electrodes yields the polarization-dependent open-circuit photovoltage with a dichroic ratio of 2.0 under 405 nm light illumination. The reintroduction of ferroelectric Sn2P2S6 to the 2D asymmetric semiconductor family provides possibilities to hardware implement of the self-powered polarization-sensitive photodetection and spotlights the promising applications for next-generation photovoltaic devices.

13.
Crit Rev Oncol Hematol ; 196: 104273, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382772

RESUMO

BACKGROUND: Researchers have shown that using next-generation hormonal agents (NHA) for castration-resistant prostate cancer (CRPC) would lead to increased risk of cardiac adverse effects, making clinician choices more complex. METHODS: We systematically searched Pubmed, Cochrane Library, and Embase databases for research published before October 2022. Agents were ranked according to their effectiveness based on cardiac adverse effects using the surface under the cumulative ranking curve. RESULTS: A total of 21 Randomized Controlled Trials (RCT) with 19, 083 patients were included in present study. Our results showed that abiraterone and enzalutamide could lead to a significantly higher hypertension rate compared with placebo; whereas no significant difference was detected between four NHAs and placebo in ischemic heart disease incidence. All four NHAs could significantly increase the risk of cardiotoxicity. CONCLUSIONS: NHAs are generally acceptable in terms of cardiovascular disease compared to placebo in patients with CRPC.


Assuntos
Metanálise em Rede , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Antineoplásicos Hormonais/uso terapêutico , Antineoplásicos Hormonais/efeitos adversos , Cardiotoxicidade/etiologia , Cardiotoxicidade/epidemiologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Heliyon ; 10(2): e24330, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38288011

RESUMO

In the past few decades, organic solvent nanofiltration (OSN) has attracted numerous researchers and broadly applied in various fields. Unlike conventional nanofiltration, OSN always faced a broad spectrum of solvents including polar solvents and non-polar solvents. Among those recently developed OSN membranes in lab-scale or widely used commercial membranes, researchers preferred to explore intrinsic materials or introduce nanomaterials into membranes to fabricate OSN membranes. However, the hydrophilicity of the membrane surface towards filtration performance was often ignored, which was the key factor in conventional aqueous nanofiltration. The influence of surface hydrophilicity on OSN performance was not studied systematically and thoroughly. Generally speaking, the hydrophilic OSN membranes performed well in the polar solvents while the hydrophobic OSN membranes work well in the non-polar solvent. Many review papers reviewed the basics, problems of the membranes, up-to-date studies, and applications at various levels. In this review, we have focused on the relationship between the surface hydrophilicity of OSN membranes and OSN performances. The history, theory, and mechanism of the OSN process were first recapped, followed by summarizing representative OSN research classified by surface hydrophilicity and types of membrane, which recent OSN research with its contact angles and filtration performance were listed. Finally, from the industrialization perspective, the application progress of hydrophilic and hydrophobic OSN membranes was introduced. We started with history and theory, presented many research and application cases of hydrophilic and hydrophobic OSN membranes, and discussed anticipated progress in the OSN field. Also, we pointed out some future research directions on the hydrophilicity of OSN membranes to deeply develop the effect made by membrane hydrophilicity on OSN performance for future considerations and stepping forward of the OSN industry.

15.
Huan Jing Ke Xue ; 45(1): 61-70, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216458

RESUMO

In August 2022, Chengdu and Chongqing showed significant differences in ozone (O3) pollution. Chengdu had O3 pollution days for 20 days, whereas Chongqing had no O3 pollution days. In this study, we analyzed the influencing factors of this difference from the emission level of precursors and meteorological conditions. The results showed that:① the total mixing ratio of 52 VOCs (volatile organic compounds) (including 26 alkanes, 16 aromatics, and 10 alkenes) in Chengdu (18.8×10-9) was 2.8 times that of Chongqing (6.6×10-9), and the total O3 formation potential (OFP) (51.2×10-9) was 2.0 times that of Chongqing (25.0×10-9). The·OH radical loss rate (L·OH) (3.9 s-1) was 1.7 times that of Chongqing (2.3 s-1). The top three OFP in Chengdu were ethylene, m/p-xylene, and isoprene, and those in Chongqing were isoprene, ethylene, and propylene. The contribution rate of alkenes to O3 in Chongqing was 60.7%, whereas the OFP of alkenes and aromatics in Chengdu were 1.6 times and 2.9 times that in Chongqing. In conclusion, the total mixing ratio of VOCs, atmospheric photochemical activity, and O3 formation potential of Chengdu were higher than those of Chongqing. ② Isoprene was ranked first place in L·OH in both Chengdu and Chongqing, indicating that the contribution of biogenic sources to O3 pollution in August was significant. However, the biogenic source emission activity was in response to temperature. From August 14 to 24, the high temperature in Chongqing (38.3℃) decreased biogenic source emission activity, whereas the temperature in Chengdu (34.9℃) increased the biogenic sources emission activity. ③ The horizontal and vertical atmospheric diffusion conditions of Chongqing were better than those of Chengdu, and Chengdu was affected by regional pollution transmission.

16.
Huan Jing Ke Xue ; 45(1): 48-60, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216457

RESUMO

To investigate the characteristics, source apportionment, and potential source areas of carbonaceous aerosols in Chongqing during winter, PM2.5 samples were collected from January 2021 to February 2021 in the urban areas of Wanzhou (WZ), Yubei (YB), and Shuangqiao (SQ). The results showed that the average mass concentrations of PM2.5, OC, and EC in SQ were (72.6 ±33.3), (18.2 ±8.2), and (4.4 ±1.7) µg·m-3, respectively, higher than those in WZ[(67.2 ±30.3), (17.2 ±7.4), and (5.1 ±2.4) µg·m-3] and YB[(63.4 ±25.7), (15.4 ±6.3), and (4.2 ±1.9) µg·m-3]. Compared with that during the clear period, the concentration and fraction of EC in total carbon increased by 103.0% and 8.1%, respectively, in WZ compared to that in other areas during pollution period, whereas the OC/EC ratio was decreased significantly (-10.5%), indicating that the primary emission of carbonaceous aerosols increased significantly during the pollution period. The average mass concentrations of secondary organic carbon (SOC) in SQ and YB were (7.7 ±4.8) µg·m-3 and (6.9 ±2.8) µg·m-3 significantly higher, respectively, than that in WZ[(4.5 ±1.9) µg·m-3] during the campaign. This indicated that the secondary transformation had a greater influence on the carbonaceous aerosols in SQ and YB than that in WZ. Furthermore, in contrast to that in WZ, the ratios of SOC/OC were increased with the increase in PM2.5 concentrations, and significant correlations between SOC concentration and aerosol water content, NO2 concentration, and the value of NOR were observed in SQ and YB (P < 0.01), indicating that the increasing of carbonaceous aerosol concentrations might be mainly driven by the SOC with -NO2 groups produced by aqueous chemical reactions during winter in SQ and YB. The positive definite matrix factor (PMF) results in these urban areas showed that the contribution of biomass/coal combustion source in WZ (47.4%) was significantly higher than that in YB (34.2%) and SQ (38.1%), whereas the gasoline motor vehicle emission and secondary transformation impacts were more significant in YB. The results of the concentration weighted trajectory (CWT) showed that the potential sources of carbonaceous aerosols were mainly the local and northeastern parts of these urban areas (such as Changshou).

17.
Small ; 20(8): e2307863, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37822157

RESUMO

The low energy efficiency and limited cycling life of rechargeable Zn-air batteries (ZABs) arising from the sluggish oxygen reduction/evolution reactions (ORR/OERs) severely hinder their commercial deployment. Herein, a zeolitic imidazolate framework (ZIF)-derived strategy associated with subsequent thermal fixing treatment is proposed to fabricate dual-atom CoFe─N─C nanorods (Co1 Fe1 ─N─C NRs) containing atomically dispersed bimetallic Co/Fe sites, which can promote the energy efficiency and cyclability of ZABs simultaneously by introducing the low-potential oxidation redox reactions. Compared to the mono-metallic nanorods, Co1 Fe1 ─N─C NRs exhibit remarkable ORR performance including a positive half-wave potential of 0.933 V versus reversible hydrogen electrode (RHE) in alkaline electrolyte. Surprisingly, after introducing the potassium iodide (KI) additive, the oxidation overpotential of Co1 Fe1 ─N─C NRs to reach 10 mA cm-2 can be significantly reduced by 395 mV compared to the conventional destructive OER. Theoretical calculations show that the markedly decreased overpotential of iodide oxidation can be ascribed to the synergistic effects of neighboring Co─Fe diatomic sites as the unique adsorption sites. Overall, aqueous ZABs assembled with Co1 Fe1 ─N─C NRs and KI as the air-cathode catalyst and electrolyte additive, respectively, can deliver a low charging voltage of 1.76 V and ultralong cycling stability of over 230 h with a high energy efficiency of ≈68%.

18.
Small ; 20(6): e2305700, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37797186

RESUMO

It is challenging yet promising to design highly accessible N-doped carbon skeletons to fully expose the active sites inside single-atom catalysts. Herein, mesoporous N-doped carbon hollow spheres with regulatable through-pore size can be formulated by a simple sequential synthesis procedure, in which the condensed SiO2 is acted as removable dual-templates to produce both hollow interiors and through-pores, meanwhile, the co-condensed polydopamine shell is served as N-doped carbon precursor. After that, Fe─N─C hollow spheres (HSs) with highly accessible active sites can be obtained after rationally implanting Fe single-atoms. Microstructural analysis and X-ray absorption fine structure analysis reveal that high-density Fe─N4 active sites together with tiny Fe clusters are uniformly distributed on the mesoporous carbon skeleton with abundant through-pores. Benefitted from the highly accessible Fe─N4 active sites arising from the unique through-pore architecture, the Fe─N─C HSs demonstrate excellent oxygen reduction reaction (ORR) performance in alkaline media with a half-wave potential up to 0.90 V versus RHE and remarkable stability, both exceeding the commercial Pt/C. When employing Fe─N─C HSs as the air-cathode catalysts, the assembled Zn-air batteries deliver a high peak power density of 204 mW cm-2 and stable discharging voltage plateau over 140 h.

19.
Anticancer Drugs ; 35(1): 1-11, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37104099

RESUMO

Gastric cancer has been a constant concern to researchers as one of the most common malignant tumors worldwide. The treatment options for gastric cancer include surgery, chemotherapy and traditional Chinese medicine. Chemotherapy is an effective treatment for patients with advanced gastric cancer. Cisplatin (DDP) has been approved as a critical chemotherapy drug to treat various kinds of solid tumors. Although DDP is an effective chemotherapeutic agent, many patients develop drug resistance during treatment, which has become a severe problem in clinical chemotherapy. This study aims to investigate the mechanism of DDP resistance in gastric cancer. The results show that intracellular chloride channel 1 (CLIC1) expression was increased in AGS/DDP and MKN28/DDP, and as compared to the parental cells, autophagy was activated. In addition, the sensitivity of gastric cancer cells to DDP was decreased compared to the control group, and autophagy increased after overexpression of CLIC1. On the contrary, gastric cancer cells were more sensitive to cisplatin after transfection of CLIC1siRNA or treatment with autophagy inhibitors. These experiments suggest that CLIC1 could alter the sensitivity of gastric cancer cells to DDP by activating autophagy. Overall, the results of this study recommend a novel mechanism of DDP resistance in gastric cancer.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/metabolismo , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Autofagia , Linhagem Celular Tumoral , Apoptose , Proliferação de Células , Canais de Cloreto/genética , Canais de Cloreto/farmacologia , Canais de Cloreto/uso terapêutico
20.
Small ; 20(7): e2305658, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37798674

RESUMO

Defect engineering is promising to tailor the physical properties of 2D semiconductors for function-oriented electronics and optoelectronics. Compared with the extensively studied 2D binary materials, the origin of defects and their influence on physical properties of 2D ternary semiconductors are not clarified. Here, the effect of defects on the electronic structure and optical properties of few-layer hexagonal Znln2 S4 is thoroughly studied via versatile spectroscopic tools in combination with theoretical calculations. It is demonstrated that the Zn-In antistructural defects induce the formation of a series of donor and acceptor energy levels and sulfur vacancies induce donor energy levels, leading to rich recombination paths for defect emission and extrinsic absorption. Impressively, the emission of donor-acceptor pair in Znln2 S4 can be significantly tailored by electrostatic gating due to efficient tunability of Fermi level (Ef ). Furthermore, the layer-dependent dipole orientation of defect emission in Znln2 S4 is directly revealed by back focal plane imagining, where it presents obviously in-plane dipole orientation within a dozen-layer thickness of Znln2 S4 . These unique features of defects in Znln2 S4 including extrinsic absorption, rich recombination paths, gate tunability, and in-plane dipole orientation are definitely a benefit to the advanced orientation-functional optoelectronic applications.

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