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1.
Eur J Pharm Sci ; 197: 106767, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38636781

RESUMO

Triple-negative breast cancer (TNBC) is a unique breast cancer subtype characterized by a lack of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expression. Since TNBC lacks ER, PR, and HER2, there are currently no drugs that specifically target TNBC. Therefore, the development of new drugs or effective treatment strategies to target TNBC has become an urgent clinical need. Research has shown that the application of histone deacetylase (HDAC) inhibitors and DNA methyltransferase (DNMT) inhibitors leads to genomic and epigenomic instability. This, in turn, triggers the activation of pattern recognition receptors (PRRs) and subsequently activates downstream interferon (IFN) signalling pathways. In this study, the bifunctional HDAC and DNMT inhibitor J208 exhibited antitumour activity in TNBC cell lines. J208 effectively induced apoptosis and cell cycle arrest at the G0/G1 phase, inhibiting cell migration and invasion in TNBC. Moreover, this bifunctional inhibitor induced the expression of endogenous retroviruses (ERVs) and elicited a viral mimicry response, which increased the intracellular levels of double-stranded RNA (dsRNA) to activate the innate immune signalling pathway in TNBC. In summary, we demonstrated that the bifunctional inhibitor J208, which is designed to inhibit HDAC and DNMT, has potent anticancer effects, providing a new research basis for reactivating antitumour immunity by triggering innate immune signalling and offering a promising strategy for TNBC treatment.

2.
BMC Geriatr ; 24(1): 314, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575871

RESUMO

BACKGROUND AND OBJECTIVES: It is known that difficulty sleeping after a fracture can have negative effects on both mental and physical health and may prolong the recovery process. The objective of this study is to explore how sleep quality and psychological health are linked in patients with pelvic and acetabulum fractures. METHODS: A study was conducted on 265 patients between 2018 and 2022 who had suffered pelvic and acetabulum fractures. The study examined various factors, including age, gender, cause of injury, post-operative complications, and injury severity. The study employed ordinal logistic regression to examine the relationship between various pelvic fractures and seven subscales of the Majeed Pelvic Score (MPS), as well as the Sleep Disorder Questionnaire (SDQ) and Beck Depression Inventory (BDI). The study focused on the postoperative outcome one year after surgery, and each patient was assessed at the one-year mark after surgical intervention. Additionally, the study evaluated the functional outcome, sleep quality, and psychological disorders of the patients. RESULTS: From 2018 to 2022, a total of 216 patients suffered from pelvic and acetabulum fractures. Among them, 6.6% experienced borderline clinical depression, and 45.2% reported mild mood disturbances. Anxiety was found to be mild to moderate in 46% of Tile C and posterior acetabulum wall fracture patients. About 24.8% of patients reported insomnia, while 23.1% reported sleep movement disorders. However, no significant correlation was found between fracture types and sleep disorders. The mean Majeed pelvic score (MPS) was 89.68. CONCLUSIONS: Patients with pelvic and acetabular fractures typically experience functional improvement, but may also be at increased risk for insomnia and sleep movement disorders, particularly for certain types of fractures. Psychological well-being varies between fracture groups, with signs of borderline clinical depression observed in some cases. However, anxiety levels do not appear to be significantly correlated with pelvic and acetabular fractures.


Assuntos
Fraturas Ósseas , Fraturas do Quadril , Transtornos dos Movimentos , Ossos Pélvicos , Distúrbios do Início e da Manutenção do Sono , Fraturas da Coluna Vertebral , Humanos , Acetábulo/lesões , Estudos Transversais , Qualidade do Sono , Fraturas Ósseas/complicações , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/cirurgia , Ossos Pélvicos/cirurgia , Ossos Pélvicos/lesões , Estudos Retrospectivos
3.
Science ; 384(6693): 301-306, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38635711

RESUMO

China's massive wave of urbanization may be threatened by land subsidence. Using a spaceborne synthetic aperture radar interferometry technique, we provided a systematic assessment of land subsidence in all of China's major cities from 2015 to 2022. Of the examined urban lands, 45% are subsiding faster than 3 millimeters per year, and 16% are subsiding faster than 10 millimeters per year, affecting 29 and 7% of the urban population, respectively. The subsidence appears to be associated with a range of factors such as groundwater withdrawal and the weight of buildings. By 2120, 22 to 26% of China's coastal lands will have a relative elevation lower than sea level, hosting 9 to 11% of the coastal population, because of the combined effect of city subsidence and sea-level rise. Our results underscore the necessity of enhancing protective measures to mitigate potential damages from subsidence.

4.
Medicine (Baltimore) ; 103(12): e37467, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38518020

RESUMO

Previous observational studies have observed a correlation between sedentary behavior and osteoporosis. However, conclusions from these studies have been contradictory. To explore the potential causal relationship between sedentary behavior and osteoporosis, we conducted a Mendelian randomization analysis. A two-sample Mendelian randomization was adopted to explore the causal relationship of leisure sedentary behavior with osteoporosis. We employed 5 methods to estimate the causal associations between leisure sedentary behavior and osteoporosis. Univariable Mendelian randomization results provided evidence for the causal relationship of the time spent on computer-use with the bone mineral density estimated by heel quantitative ultrasound (eBMD) (inverse variance weighted [IVW]: ß (95% confidence interval [CI]) - 0.150 (-0.270 to -0.031), P = .013; weighted median: ß (95%CI) - 0.195 (-0.336 to -0.055), P = .006). Similar associations were observed in the driving forearm bone mineral density (FABMD) (IVW: ß (95%CI) - 0.933 (-1.860 to -0.007), P = .048) and driving lumbar spine bone mineral density (IVW: ß (95%CI) - 0.649 (-1.175 to -0.124), P = .015). However, we did not find a significant causal relationship between the time spent on watching TV and bone mineral density. Research showed that there was a causal relationship between the time spent on computer use and driving time and eBMD, FABMD, and lumbar spine bone mineral density.


Assuntos
Síndrome de Cogan , Osteoporose , Comportamento Sedentário , Humanos , Análise da Randomização Mendeliana , Osteoporose/etiologia , Osteoporose/genética , Densidade Óssea/genética , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único
5.
Cancer Cell Int ; 24(1): 98, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443969

RESUMO

Tumor organoids, especially patient-derived organoids (PDOs) exhibit marked similarities in histopathological morphology, genomic alterations, and specific marker expression profiles to those of primary tumour tissues. They are applied in various fields including drug screening, gene editing, and identification of oncogenes. However, CAR-T therapy in the treatment of solid tumours is still at an exploratory stage. Tumour organoids offer unique advantages over other preclinical models commonly used for CAR-T therapy research, which the preservation of the biological characteristics of primary tumour tissue is critical for the study of early-stage solid tumour CAR-T therapies. Although some investigators have used this co-culture model to validate newly targeted CAR-T cells, optimise existing CAR-T cells and explore combination therapy strategies, there is still untapped potential in the co-culture models used today. This review introduces the current status of the application of tumour organoid and CAR-T cell co-culture models in recent years and commented on the limitations of the current co-cultivation model. Meanwhile, we compared the tumour organoid model with two pre-clinical models commonly used in CAR-T therapy research. Eventually, combined with the new progress of organoid technologies, optimization suggestions were proposed for the co-culture model from five perspectives: preserving or reconstructing the tumor microenvironment, systematization, vascularization, standardized culture procedures, and expanding the tumor organoids resource library, aimed at assisting related researchers to better utilize co-culture models.

6.
Aging (Albany NY) ; 16(5): 4250-4269, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38407978

RESUMO

Lei's formula (LSF), a traditional Chinese herbal remedy, is recognized for its remarkable clinical effectiveness in treating osteoarthritis (OA). Despite its therapeutic potential, the exact molecular mechanisms underlying LSF's action in OA have remained enigmatic. Existing research has shed light on the role of the mTOR signaling pathway in promoting chondrocyte senescence, a central factor in OA-related cartilage degeneration. Consequently, targeting mTOR to mitigate chondrocyte senescence presents a promising avenue for OA treatment. The primary objective of this study is to establish LSF's chondroprotective potential and confirm its anti-osteoarthritic efficacy through mTOR inhibition. In vivo assessments using an OA mouse model reveal substantial articular cartilage degeneration. However, LSF serves as an effective guardian of articular cartilage, evidenced by reduced subchondral osteosclerosis, increased cartilage thickness, improved surface smoothness, decreased OARSI scores, elevated expression of cartilage anabolic markers (Col2 and Aggrecan), reduced expression of catabolic markers (Adamts5 and MMP13), increased expression of the chondrocyte hypertrophy marker (Col10), and decreased expression of chondrocyte senescence markers (P16 and P21). In vitro findings demonstrate that LSF shields chondrocytes from H2O2-induced apoptosis, inhibits senescence, enhances chondrocyte differentiation, promotes the synthesis of type II collagen and proteoglycans, and reduces cartilage degradation. Mechanistically, LSF suppresses chondrocyte senescence through the mTOR axis, orchestrating the equilibrium between chondrocyte anabolism and catabolism, ultimately leading to reduced apoptosis and decelerated OA cartilage degradation. LSF holds significant promise as a therapeutic approach for OA treatment, offering new insights into potential treatments for this prevalent age-related condition.


Assuntos
Cartilagem Articular , Osteoartrite , Camundongos , Animais , Condrócitos/metabolismo , Peróxido de Hidrogênio/farmacologia , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Cartilagem Articular/metabolismo
7.
Mol Med Rep ; 29(3)2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38240082

RESUMO

The intracellular pathway of Janus kinase/signal transducer and activator of transcription (JAK/STAT) and modification of nucleosome histone marks regulate the expression of proinflammatory mediators, playing an essential role in carcinogenesis, antiviral immunity and the interaction of host proteins with Herpesviral particles. The pathway has also been suggested to play a vital role in the clinical course of the acute infection caused by severe acute respiratory syndrome coronavirus type 2 (SARS­CoV­2; known as coronavirus infection­2019), a novel human coronavirus initially identified in the central Chinese city Wuhan towards the end of 2019, which evolved into a pandemic affecting nearly two million people worldwide. The infection mainly manifests as fever, cough, myalgia and pulmonary involvement, while it also attacks multiple viscera, such as the liver. The pathogenesis is characterized by a cytokine storm, with an overproduction of proinflammatory mediators. Innate and adaptive host immunity against the viral pathogen is exerted by various effectors and is regulated by different signaling pathways notably the JAK/STAT. The elucidation of the underlying mechanism of the regulation of mediating factors expressed in the viral infection would assist diagnosis and antiviral targeting therapy, which will help overcome the infection caused by SARS­CoV­2.


Assuntos
COVID-19 , Herpesviridae , Humanos , Carcinogênese , Herpesviridae/metabolismo , Janus Quinases/metabolismo , SARS-CoV-2/metabolismo , Transdução de Sinais/fisiologia , Fatores de Transcrição STAT/metabolismo
8.
World J Clin Cases ; 11(29): 7061-7074, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37946765

RESUMO

BACKGROUND: Gait is influenced by race, age, and diseases type. Reference values for gait are closely related to numerous health outcomes. To gain a comprehensive understanding of gait patterns, particularly in relation to race-related pathologies and disorders, it is crucial to establish reference values for gait in daily life considering sex and age. Therefore, our objective was to present sex and age-based reference values for gait in daily life, providing a valuable foundation for further research and clinical applications. AIM: To establish reference values for lower extremity joint kinematics and kinetics during gait in asymptomatic adult women and men. METHODS: Spatiotemporal, kinematics and kinetics parameters were measured in 171 healthy adults (70 males and 101 females) using the computer-aided soft tissue foot model. Full curve statistical parametric mapping was performed using independent and paired-samples t-tests. RESULTS: Compared with females, males required more time (cycle time, double-limb support time, stance time, swing time, and stride time), and the differences were statistically significant. In addition, the step and stride lengths of males were longer. Compared to males, female cadence was faster, and statures-per-second and stride-per-minute were higher. There were no statistical differences in speed and stride width between the two groups. After adjusting for height, it was observed that women walked significantly faster than men, and they also had a higher cadence. However, in terms of step length, stride length, and stride width, both genders exhibited similarities. CONCLUSION: We established reference values for gait speed and spatiotemporal gait parameters in Chinese university students. This contributes to a valuable database for gait assessment and evaluation of preventive or rehabilitative programs.

9.
Environ Sci Pollut Res Int ; 30(56): 118942-118949, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37922079

RESUMO

New low-cost rural sewage collection and treatment technologies should be developed to solve the problem of conventional rural sewage technology caused by rural sewage characteristics. In this study, a novel facility, the construction waste ditch, was established to collect and treat household rural sewage, making use of the collection capacity of ditches and the treatment capacity of construction wastes, and the structure parameters were optimized. Results show that the construction waste ditch achieved pollutant removal phenomenon (average removal rates were above 25% and the maximum rates were more than 50%) and structural parameters (baffles number, height, and angle) influenced the pollutant removal ability significantly. Five baffles, 4-5 cm baffle height and 0-25° baffle angle were effective with different scenarios. This technology had the advantage of high pollutant removal capacity and tolerant of influent concentration fluctuation, having potential for popularization and application.


Assuntos
Poluentes Ambientais , Esgotos , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Instalações de Saúde
10.
Front Endocrinol (Lausanne) ; 14: 1200892, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38027166

RESUMO

Objective: To explore the causal association between breakfast skipping and bone mineral density (BMD) through two-sample Mendelian randomisation (MR) analysis. Methods: A two-sample MR approach was adopted to explore the causal relationship of breakfast skipping with BMDs (across three skeletal sites and five age groups). Publicly available genome-wide association study summary data were used for MR analysis. We used five methods to estimate the causal associations between breakfast skipping and BMDs: inverse-variance weighting (IVW), MR-Egger, weighted median, simple mode, and weighted mode. IVW was used for the main analysis and the remaining four methods were used as supplementary analyses. The heterogeneity of the MR results was determined using IVW and MR-Egger methods. The pleiotropy of the MR results was determined using MR-Egger intercept. Furthermore, a leave-one-out test was performed to determine whether the MR results were affected by a single nucleotide polymorphism. Results: With the IVW method, we did not find any causal relationship between breakfast skipping and forearm, femoral neck, and lumbar spine BMD. Subsequently, when we included BMD data stratified by five different age groups in the analysis, the results showed that there was no apparent causal effect between breakfast skipping and age-stratified BMD. This finding was supported by all four supplementary methods (P > 0.05 for all methods). No heterogeneity or horizontal pleiotropy was detected in any of the analyses (P > 0.05). The leave-one-out tests conducted in the analyses did not identify any single nucleotide polymorphism that could have influenced the MR results, indicating the reliability of our findings. Conclusion: No causal effect was found between breakfast skipping and BMD (across three skeletal sites and five age groups).


Assuntos
Densidade Óssea , Desjejum , Densidade Óssea/genética , Causalidade , Estudo de Associação Genômica Ampla , Reprodutibilidade dos Testes , Análise da Randomização Mendeliana
11.
Nanotechnology ; 35(5)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37879321

RESUMO

Transition metal selenides are considered as promising anode materials for fast-charging sodium-ion batteries due to their high theoretical specific capacity. However, the low intrinsic conductivity, particle aggregation, and large volume expansion problems can severely inhibit the high-rate and long-cycle performance of the electrode. Herein, FeSe2nanoparticles embedded in nitrogen-doped carbon nanofibers (FeSe2@NCF) have been synthesized using the electrospinning and selenization process, which can alleviate the volume expansion and particle aggregation during the sodiation/desodiation and improve the electrical conductivity of the electrode. The FeSe2@NCF electrode delivers the outstanding specific capacity of 222.3 mAh g-1at a fast current density of 50 A g-1and 262.1 mAh g-1at 10 A g-1with the 87.8% capacity retention after 5000 cycles. Furthermore, the Na-ion full cells assembled with pre-sodiated FeSe2@NCF as anode and Na3V2(PO4)3/C as cathode exhibit the reversible specific capacity of 117.6 mAh g-1at 5 A g-1with the 84.3% capacity retention after 1000 cycles. This work provides a promising way for the conversion-based metal selenides for the applications as fast-charging sodium-ion battery anode.

12.
J Orthop Surg Res ; 18(1): 654, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667295

RESUMO

BACKGROUND AND OBJECTIVES: Local anesthetics (LAs) are widely used to infiltrate into surgical wounds for postoperative analgesia. Different adjuvants like dexamethasone and dexmedetomidine, when added to LA agents, could improve and prolong analgesia. The aim of this trial was to evaluate the analgesic efficacy and opioid-sparing properties of dexamethasone and dexmedetomidine when added to ropivacaine for wound infiltration in transforaminal lumbar interbody fusion (TLIF). METHODS: We conducted a controlled study among 68 adult patients undergoing TLIF, which was prospective, randomized and double-blind in nature. The participants were divided into four equal groups at random. Group R was given 150 mg of 1% ropivacaine (15 mL) and 15 mL of normal saline. Group R + DXM received 150 mg of 1% ropivacaine (15 mL) and 10 mg of dexamethasone (15 mL). Group R + DEX received 150 mg of 1% ropivacaine (15 mL) and 1 µg/kg of dexmedetomidine (15 mL). Lastly, group R + DXM + DEX was given 150 mg of 1% ropivacaine (15 mL), 10 mg of dexamethasone and 1 µg/kg of dexmedetomidine (15 mL). The primary focus was on the length of pain relief provided. Additionally, secondary evaluations included the amount of hydromorphone taken after surgery, the numerical rating scale and safety assessments within 48 h after the operation. RESULTS: Based on the p value (P > 0.05), there was no significant variance in the duration of pain relief or the total usage of hydromorphone after surgery across the four groups. Similarly, the numerical rating scale scores at rest and during activity at 6-, 12-, 24- and 48-h post-surgery for all four groups showed no difference (P > 0.05). However, the incidence of delayed anesthesia recovery was slightly higher in group R + DEX and group R + DXM + DEX when compared to group R or group R + DXM. Furthermore, there were no significant differences between the four groups in terms of vomiting, nausea, dizziness or delayed anesthesia recovery. CONCLUSION: For wound infiltration in TLIF, the addition of dexamethasone and dexmedetomidine to ropivacaine did not result in any clinically significant reduction in pain or opioid consumption and could prompt some side effects.


Assuntos
Adjuvantes Anestésicos , Analgesia , Dexametasona , Dexmedetomidina , Fusão Vertebral , Adulto , Humanos , Analgesia/métodos , Analgésicos Opioides , Dexametasona/administração & dosagem , Dexmedetomidina/administração & dosagem , Hidromorfona , Vértebras Lombares/cirurgia , Dor , Estudos Prospectivos , Ropivacaina/administração & dosagem , Fusão Vertebral/efeitos adversos , Adjuvantes Anestésicos/administração & dosagem , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Anestesia Local/métodos
13.
Environ Res ; 237(Pt 2): 117024, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37657606

RESUMO

Bacteria in rural sewage collection systems have the important influences on operation and maintenance risks, such as sedimentation blockage and harmful gas accumulation, and pollutant pre-treatment ability. It is necessary to analyze and interpret the influence on bacterial communities caused by the location (sewage, biofilms, and deposits), season (winter and spring, summer and autumn), and system type (sewers and ditches) to better understand the bacterial characteristics in rural sewage collection systems. To achieve the above purpose, 96 samples obtained from practical rural sewage collection systems in eight villages were analyzed by 16S rRNA whole region sequencing methods. The results indicate that locations and seasons caused significant influences on the overall bacterial communities, which were mainly affected by temperature, sewage quality and bacterial survival preference, and 13 genera of sulfate-reducing bacteria (SRB), 2 genera of ammonia-oxidizing bacteria (AOB), 2 genera of nitrite-oxidizing bacteria (NOB), and 9 genera of water-related pathogenic bacteria (WPB) were detected in rural sewage collection systems. SRB, AOB, NOB, and WPB tended to inhabit in biofilms or deposits rather than in sewage. The total relative abundance of SRB in summer and autumn (∼2.19%) was higher than in winter and spring (∼0.41%), and the WPB distribution in different seasons showed significant distinction. Additionally, some of SRB, AOB, NOB, and WPB also showed significant differences in sewers and ditches. Overall, this study provided a deeper understanding of bacteria in rural sewage collection systems and could further provide the basic parameter for the operation and maintenance risk control.

14.
Light Sci Appl ; 12(1): 199, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37607910

RESUMO

A high-brightness ultrabroadband supercontinuum white laser is desirable for various fields of modern science. Here, we present an intense ultraviolet-visible-infrared full-spectrum femtosecond laser source (with 300-5000 nm 25 dB bandwidth) with 0.54 mJ per pulse. The laser is obtained by sending a 3.9 µm, 3.3 mJ mid-infrared pump pulse into a cascaded architecture of gas-filled hollow-core fiber, a bare lithium niobate crystal plate, and a specially designed chirped periodically poled lithium niobate crystal, under the synergic action of second and third order nonlinearities such as high harmonic generation and self-phase modulation. This full-spectrum femtosecond laser source can provide a revolutionary tool for optical spectroscopy and find potential applications in physics, chemistry, biology, material science, industrial processing, and environment monitoring.

15.
Nanomaterials (Basel) ; 13(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37513068

RESUMO

Composite bipolar plates (BPs) hinder their application in proton exchange membrane fuel cells (PEMFC) because of their poor conductivity and mechanical properties. Nanofillers can effectively solve this problem but often have a limited effect due to their easy agglomeration. In this work, a continuous mesh carboxylated multi-walled carbon nanotube (MWCNT) coating on the surface of graphite was synthesized by chemical vapor deposition (CVD) and carboxylation modification, and the composite BPs were prepared by molding using prepared reticulated carboxylated MWCNTs, expanded graphite, and resin. By optimizing the carboxylation treatment time and the content of the nano-filler, the composite BPs had the best performance at a 15 min carboxylation treatment time and 2.4% filler content. The planar conductivity reached up to 243.52 S/cm, while the flexural strength increased to 61.9 MPa. The thermal conductivity and hydrophobicity were improved compared with the conventional graphite/resin composite BPs, and good corrosion resistance has been demonstrated under the PEMFC operating environment. This work provides a novel nanofiller modification paradigm for PBs.

16.
Opt Express ; 31(15): 23923-23930, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37475232

RESUMO

Matter manipulation in terahertz range calls for a strong-field broadband light source. Here, we present a scheme for intense terahertz generation from DSTMS crystal driven by a high power optical parametric chirped pulse amplifier. The generated terahertz energy is up to 175 µJ with a peak electric field of 17 MV/cm. The relationship between terahertz energy, conversion efficiency, and pump fluence is demonstrated. This study provides a powerful driving light source for strong-field terahertz pump-probe experimentation.

17.
Adv Mater ; 35(41): e2304082, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37391190

RESUMO

Carbon nanotubes (CNTs) possess extremely anisotropic electronic, thermal, and optical properties owing to their 1D character. While their linear optical properties have been extensively studied, nonlinear optical processes, such as harmonic generation for frequency conversion, remain largely unexplored in CNTs, particularly in macroscopic CNT assemblies. In this work, macroscopic films of aligned and type-separated (semiconducting and metallic) CNTs are synthesized and polarization-dependent third-harmonic generation (THG) from the films with fundamental wavelengths ranging from 1.5 to 2.5 µm is studied. Both films exhibited strongly wavelength-dependent, intense THG signals, enhanced through exciton resonances, and third-order nonlinear optical susceptibilities of 2.50 × 10-19  m2  V-2 (semiconducting CNTs) and 1.23 × 10-19  m2  V-2 (metallic CNTs), respectively are found, for 1.8 µm excitation. Further, through systematic polarization-dependent THG measurements, the values of all elements of the susceptibility tensor are determined, verifying the macroscopically 1D nature of the films. Finally, polarized THG imaging is performed to demonstrate the nonlinear anisotropy in the large-size CNT film with good alignment. These findings promise applications of aligned CNT films in mid-infrared frequency conversion, nonlinear optical switching, polarized pulsed lasers, polarized long-wave detection, and high-performance anisotropic nonlinear photonic devices.

18.
Chemosphere ; 335: 139142, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37290510

RESUMO

Perfluorooctanoic acid (PFOA) as nonbiodegradable organic pollutant, its presence and risks in wastewater treatment system has aroused wide concern. This study investigated the effect and underlying mechanism of PFOA on anaerobic digestion sludge (ADS) dewaterability. Long-term exposure experiments were set up to investigate the effect with various concentration of PFOA dosed. Experimental results suggested that the existence of high concentration PFOA (over 1000 µg/L) could deteriorate ADS dewaterability. The long-term exposure to 100,000 µg/L PFOA of ADS increased specific resistance filtration (SRF) by 81.57%. It was found that PFOA promoted the release of extracellular polymeric substances (EPS), which was strongly associated with sludge dewaterability. The fluorescence analysis revealed that the high PFOA concentration could significantly improve the percentage of protein-like substances and soluble microbial by-product-like content, and then further deteriorated the dewaterability. The FTIR results showed that long-term exposure of PFOA caused loose protein structure in sludge EPS, which led to loose sludge floc structure. The loose sludge floc structure aggravated the deterioration of sludge dewaterability. The solids-water distribution coefficient (Kd) decreased with the increase of initial PFOA concentration. Moreover, PFOA significantly affected microbial community structure. Metabolic function prediction results showed significant decrease of fermentation function exposed to PFOA. This study revealed that the PFOA with high concentration could deteriorated sludge dewaterability, which should be highly concerned.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Esgotos/química , Anaerobiose , Eliminação de Resíduos Líquidos/métodos , Caprilatos , Proteínas , Água/química
19.
J Inflamm (Lond) ; 20(1): 14, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055831

RESUMO

Osteoarthritis (OA) is a common joint disease and is the main cause of physical disability in the elderly. Currently, there is no adequate therapeutic strategy to reverse the progression of OA. Many natural plant extracts have received attention in the treatment of OA due to their potential anti-inflammatory properties, and reduced incidence of adverse events. Dioscin (Dio), a natural steroid saponin, has been demonstrated to inhibit the release of inflammatory cytokines in mouse and rat models of various diseases, and has a protective effect in chronic inflammatory diseases. However, whether Dio alleviates OA progression remains to be explored. In this research, our purposes were to investigate the therapeutic potential of Dio in OA. The results demonstrated that Dio exerted anti-inflammatory effects by repressing NO, PGE2, iNOS and COX-2. Moreover, the application of Dio could repress IL-1ß-induced overexpression of matrix metalloproteinases (MMPs, including MMP1, MMP3, and MMP13) and ADAMTS-5, and improve the synthesis of collagen II and aggrecan, which contribute to the maintenance of chondrocyte matrix homeostasis. The underlying mechanism involved the inhibition of the MAPK and NF-κB signaling pathways by Dio. Furthermore, the treatment of Dio significantly improved the pain behaviors of rat OA models. The in vivo study revealed that Dio could ameliorate cartilage erosion and degradation. These results collectively indicate that Dio can be used as a promising and effective agent for the therapy of OA.

20.
Sci Data ; 10(1): 102, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36807363

RESUMO

Individual tree structure mapping in cities is important for urban environmental studies. Despite mapping products for tree canopy cover and biomass are reported at multiple spatial scales using various approaches, spatially explicit mapping of individual trees and their three-dimensional structure is sparse. Here we produced an individual tree dataset including tree locations, height, crown area, crown volume, and biomass over the entire New York City, USA for 6,005,690 trees. Individual trees were detected and mapped from remotely sensed datasets along with their height and crown size information. Tree biomass in 296 field plots was measured and modelled using i-Tree Eco. Wall-to-wall tree biomass was mapped using relationships between field measurements and remotely sensed datasets and downscaled to individual trees. Validation using field-plot measurements indicated that our mapping products overestimated tree number, mean tree height and maximum tree height by 11.1%, 8.6%, and 5.3%, respectively. These overestimations were mainly due to the spatial and temporal mis-match between field measurements and remote sensing observations and uncertainties in tree segmentation algorithms. This dataset enables the evaluation of urban forest ecosystem services including regulating urban heat and promoting urban health, which can provide valuable insights for urban forest management and policy making.


Assuntos
Ecossistema , Árvores , Biomassa , Florestas , Cidade de Nova Iorque , Tecnologia de Sensoriamento Remoto
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