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1.
Ying Yong Sheng Tai Xue Bao ; 35(6): 1653-1660, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-39235024

RESUMEN

The construction of road infrastructure has resulted in the degradation of wildlife habitat and the decrease of ecological network connectivity and stability. Studying the impacts of road infrastructure on wildlife life and migration is significant for regional wildlife conservation and ecological network optimization. We assessed the impacts of road infrastructure on habitat suitability using the MaxEnt model based on wildlife occurrence point data in the Guangdong-Hong Kong-Macao Greater Bay Area. We constructed the ecological networks and identified ecological breakpoints using the minimum cumulative resistance model, and compared the ecological network connectivity of different scenarios with the landscape connectivity index and graph theory index. The results showed that railway and motorway significantly affected habitat suitability, causing a decrease in wildlife habitat suitability. Affected by road infrastructure, the fragmentation of ecological sources intensified, the resistance of ecological corridors increased, and the ecological network connectivity and stability significantly decreased. A total of 536 ecological breakpoints were identified, which were concentrated in the area adjacent to ecological sources. The results would provide important scientific references for wildlife habitat conservation and ecological restoration in the Guangdong-Hong Kong-Macao Greater Bay Area.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , China , Animales , Animales Salvajes/crecimiento & desarrollo , Bahías , Ecología , Hong Kong , Modelos Teóricos , Transportes , Vías Férreas
2.
Front Immunol ; 15: 1421604, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39161762

RESUMEN

Introduction: The introduction of Immune Checkpoint Inhibitors (ICIs) has marked a paradigm shift in treating Lung Squamous Cell Carcinoma (LUSC), emphasizing the urgent need for precise molecular biomarkers to reliably forecast therapeutic efficacy. This study aims to identify potential biomarkers for immunochemotherapy efficacy by focusing on plasma extracellular vesicle (EV)-derived long RNAs (exLRs). Methods: We enrolled 78 advanced LUSC patients undergoing first-line immunochemotherapy. Plasma samples were collected, and exLR sequencing was conducted to establish baseline profiles. A retrospective analysis was performed on 42 patients to identify differentially expressed exLRs. Further validation of the top differentially expressed exLRs was conducted using quantitative reverse transcription PCR (qRT-PCR). Univariate Cox analysis was applied to determine the prognostic significance of these exLRs. Based on these findings, we developed a predictive signature (p-Signature). Results: In the retrospective analysis of 42 patients, we identified 460 differentially expressed exLRs, with pathways related to leukocyte migration notably enriched among non-responders. Univariate Cox analysis revealed 45 exLRs with prognostic significance. The top 6 protein-coding exLRs were validated using qRT-PCR, identifying CXCL8, SSH3, and SDHAF1 as differentially expressed between responders and non-responders. The p-Signature, comprising these three exLRs, demonstrated high accuracy in distinguishing responders from non-responders, with an Area Under the Curve (AUC) of 0.904 in the retrospective cohort and 0.812 in the prospective cohort. Discussion: This study highlighted the potential of plasma exLR profiles in predicting LUSC treatment efficacy. Intriguingly, lower p-Signature scores were associated with increased abundance of activated CD4+ and CD8+ T cells, indicating a more robust immune environment. These findings suggest that the p-Signature could serve as a valuable tool in guiding personalized and effective therapeutic strategies for LUSC.


Asunto(s)
Biomarcadores de Tumor , Carcinoma de Células Escamosas , Vesículas Extracelulares , Neoplasias Pulmonares , Humanos , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Masculino , Femenino , Persona de Mediana Edad , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/genética , Anciano , Estudios Retrospectivos , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/inmunología , ARN Largo no Codificante/sangre , ARN Largo no Codificante/genética , Pronóstico , Resultado del Tratamiento , Inmunoterapia/métodos , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Transcriptoma
3.
Int J Mol Sci ; 25(11)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38892389

RESUMEN

Cartilage, a flexible and smooth connective tissue that envelops the surfaces of synovial joints, relies on chondrocytes for extracellular matrix (ECM) production and the maintenance of its structural and functional integrity. Melatonin (MT), renowned for its anti-inflammatory and antioxidant properties, holds the potential to modulate cartilage regeneration and degradation. Therefore, the present study was devoted to elucidating the mechanism of MT on chondrocytes. The in vivo experiment consisted of three groups: Sham (only the skin tissue was incised), Model (using the anterior cruciate ligament transection (ACLT) method), and MT (30 mg/kg), with sample extraction following 12 weeks of administration. Pathological alterations in articular cartilage, synovium, and subchondral bone were evaluated using Safranin O-fast green staining. Immunohistochemistry (ICH) analysis was employed to assess the expression of matrix degradation-related markers. The levels of serum cytokines were quantified via Enzyme-linked immunosorbent assay (ELISA) assays. In in vitro experiments, primary chondrocytes were divided into Control, Model, MT, negative control, and inhibitor groups. Western blotting (WB) and Quantitative RT-PCR (q-PCR) were used to detect Silent information regulator transcript-1 (SIRT1)/Nuclear factor kappa-B (NF-κB)/Nuclear factor erythroid-2-related factor 2 (Nrf2)/Transforming growth factor-beta (TGF-ß)/Bone morphogenetic proteins (BMPs)-related indicators. Immunofluorescence (IF) analysis was employed to examine the status of type II collagen (COL2A1), SIRT1, phosphorylated NF-κB p65 (p-p65), and phosphorylated mothers against decapentaplegic homolog 2 (p-Smad2). In vivo results revealed that the MT group exhibited a relatively smooth cartilage surface, modest chondrocyte loss, mild synovial hyperplasia, and increased subchondral bone thickness. ICH results showed that MT downregulated the expression of components related to matrix degradation. ELISA results showed that MT reduced serum inflammatory cytokine levels. In vitro experiments confirmed that MT upregulated the expression of SIRT1/Nrf2/TGF-ß/BMPs while inhibiting the NF-κB pathway and matrix degradation-related components. The introduction of the SIRT1 inhibitor Selisistat (EX527) reversed the effects of MT. Together, these findings suggest that MT has the potential to ameliorate inflammation, inhibit the release of matrix-degrading enzymes, and improve the cartilage condition. This study provides a new theoretical basis for understanding the role of MT in decelerating cartilage degradation and promoting chondrocyte repair in in vivo and in vitro cultured chondrocytes.


Asunto(s)
Cartílago Articular , Condrocitos , Melatonina , Factor 2 Relacionado con NF-E2 , FN-kappa B , Transducción de Señal , Sirtuina 1 , Factor de Crecimiento Transformador beta , Animales , Sirtuina 1/metabolismo , Sirtuina 1/genética , Factor 2 Relacionado con NF-E2/metabolismo , Melatonina/farmacología , FN-kappa B/metabolismo , Condrocitos/metabolismo , Condrocitos/efectos de los fármacos , Condrocitos/patología , Transducción de Señal/efectos de los fármacos , Cartílago Articular/metabolismo , Cartílago Articular/patología , Cartílago Articular/efectos de los fármacos , Factor de Crecimiento Transformador beta/metabolismo , Masculino , Matriz Extracelular/metabolismo , Inflamación/metabolismo , Inflamación/patología
4.
Animals (Basel) ; 14(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38731362

RESUMEN

This study investigated the efficacy of a composite probiotics composed of lactobacillus plantarum, lactobacillus reuteri, and bifidobacterium longum in alleviating oxidative stress in weaned piglets and pregnant sows. Evaluations of growth, oxidative stress, inflammation, intestinal barrier, and fecal microbiota were conducted. Results showed that the composite probiotic significantly promoted average daily gain in piglets (p < 0.05). It effectively attenuated inflammatory responses (p < 0.05) and oxidative stress (p < 0.05) while enhancing intestinal barrier function in piglets (p < 0.01). Fecal microbiota analysis revealed an increase in the abundance of beneficial bacteria such as faecalibacterium, parabacteroides, clostridium, blautia, and phascolarctobacterium in piglet feces and lactobacillus, parabacteroides, fibrobacter, and phascolarctobacterium in sow feces, with a decrease in harmful bacteria such as bacteroides and desulfovibrio in sow feces upon probiotic supplementation. Correlation analysis indicated significant negative associations of blautia with inflammation and oxidative stress in piglet feces, while treponema and coprococcus showed significant positive associations. In sow feces, lactobacillus, prevotella, treponema, and CF231 exhibited significant negative associations, while turicibacter showed a significant positive association. Therefore, the composite probiotic alleviated oxidative stress in weaned piglets and pregnant sows by modulating fecal microbiota composition.

5.
Cancer Lett ; 587: 216622, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38246224

RESUMEN

Triptolide, a natural bioactive compound derived from herbal medicine Tripterygium wilfordii, has multiple biological activities including anti-cancer effect, which is being tested in clinical trials for treating cancers. However, the exact mechanism by which Triptolide exerts its cytotoxic effects, particularly its specific protein targets, remains unclear. Here, we show that Triptolide effectively induces cytotoxicity in gastric cancer cells by increasing reactive oxygen species (ROS) levels. Further investigations reveal that ROS accumulation contributes to the induction of Endoplasmic Reticulum (ER) stress, and subsequently autophagy induction in response to Triptolide. Meanwhile, this autophagy is cytoprotective. Interestingly, through activity-based protein profiling (ABPP) approach, we identify peroxiredoxins-2 (PRDX2), a component of the key enzyme systems that act in the defense against oxidative stress and protect cells against hydroperoxides, as direct binding target of Triptolide. By covalently binding to PRDX2 to inhibit its antioxidant activity, Triptolide increases ROS levels. Moreover, overexpression of PRDX2 inhibits and knockdown of the expression of PRDX2 increases Triptolide-induced apoptosis. Collectively, these results indicate PRDX2 as a direct target of Triptolides for inducing apoptosis. Our results not only provide novel insight into the underlying mechanisms of Triptolide-induced cytotoxic effects, but also indicate PRDX2 as a promising potential therapeutic target for developing anti-gastric cancer agents.


Asunto(s)
Diterpenos , Fenantrenos , Neoplasias Gástricas , Humanos , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Gástricas/tratamiento farmacológico , Peroxirredoxinas/genética , Diterpenos/farmacología , Fenantrenos/farmacología , Autofagia , Apoptosis , Compuestos Epoxi/farmacología
6.
Small ; 20(27): e2310972, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38282180

RESUMEN

Recently, aqueous zinc-ion batteries with conversion mechanisms have received wide attention in energy storage systems on account of excellent specific capacity, high power density, and energy density. Unfortunately, some characteristics of cathode material, zinc anode, and electrolyte still limit the development of aqueous zinc-ion batteries possessing conversion mechanism. Consequently, this paper provides a detailed summary of the development for numerous aqueous zinc-based batteries: zinc-sulfur (Zn-S) batteries, zinc-selenium (Zn-Se) batteries, zinc-tellurium (Zn-Te) batteries, zinc-iodine (Zn-I2) batteries, and zinc-bromine (Zn-Br2) batteries. Meanwhile, the reaction conversion mechanism of zinc-based batteries with conversion mechanism and the research progress in the investigation of composite cathode, zinc anode materials, and selection of electrolytes are systematically introduced. Finally, this review comprehensively describes the prospects and outlook of aqueous zinc-ion batteries with conversion mechanism, aiming to promote the rapid development of aqueous zinc-based batteries.

7.
Adv Healthc Mater ; 13(8): e2303138, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37903562

RESUMEN

Multifunctional hydrogel adhesives inhibiting infections and enabling the electrical stimulation (ES) of tissue reparation are highly desirable for the healing of surgical wounds and other skin injuries. Herein, a therapeutic nanocomposite hydrogel is designed by integrating ß-cyclodextrin-embedded Ag nanoparticles (CDAgNPs) in a polyvinyl alcohol (PVA) matrix enhanced with free ß-cyclodextrin (CD) and an atypical macromolecule made of ß-glucan grafted with hyaluronic acid (HAG). The main objective is to develop a biocompatible dressing combining the electroconductivity and antibacterial activity of CDAgNPs with the cohesiveness and porosity of PVA and the anti-inflammatory, moisturizing, and cell proliferation-promoting properties of HAG. The last component, CD, is added to strengthen the network structure of the hydrogel. PVA/CD/HAG/CDAgNP exhibited excellent adhesion strength, biocompatibility, electroconductivity, and antimicrobial activity against a wide range of bacteria. In addition, the nanocomposite hydrogel has a swelling ratio and water retention capacity suitable to serve as a wound dressing. PVA/CD/HAG/CDAgNP promoted the proliferation of fibroblast in vitro, accelerated the healing of skin wounds in an animal model, and is hemostatic. Upon ES, the PVA/CD/HAG/CDAgNP nanocomposite hydrogel became more efficient both in vitro and in vivo further speeding up the skin healing process thus demonstrating its potential as a next-generation electroconductive wound dressing.


Asunto(s)
Nanopartículas del Metal , beta-Ciclodextrinas , Animales , Nanogeles , Adhesivos , Plata , Antibacterianos/química , Cicatrización de Heridas , Hidrogeles/química
8.
Small ; 19(50): e2304504, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37635108

RESUMEN

Aqueous zinc-ion batteries (AZIBs) are considered to be one of the most promising devices for large-scale energy storage systems owing to their high theoretical capacity, environmental friendliness, and safety. However, the ionic intercalation or surface redox mechanisms in conventional cathode materials generally result in unsatisfactory capacities. Conversion-type aqueous zinc-tellurium (Zn-Te) batteries have recently gained widespread attention owing to their high theoretical specific capacities. However, it remains an enormous challenge to improve the slow kinetics of the aqueous Zn-Te batteries. Here, MoO2 nanoclusters embedded in hierarchical nitrogen-doped carbon nanoflower (MoO2 /NC) hosts are successfully synthesized and loaded with Te in aqueous Zn-Te batteries. Benefitting from the highly dispersed MoO2 nanoclusters and hierarchical nanoflower structure with a large specific surface area, the electrochemical kinetics of the Te redox reaction are significantly improved. As a result, the Te-MoO2 /NC electrode exhibits superior cycling stability and a high specific capacity of 493 mAh g-1 at 0.1 A g-1 . Meanwhile, the conversion mechanism is systematically explored using a variety of ex situ characterization methods. Therefore, this study provides a novel approach for enhancing the kinetics of the Te redox reaction in aqueous Zn-Te batteries.

9.
J Colloid Interface Sci ; 652(Pt A): 285-293, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37595445

RESUMEN

Aqueous zinc ion batteries (AZIBs) have gained extensive attention due to the numerous advantages of zinc, such as low redox potential, high abundance, low cost as well as high theoretical specific capacity. However, the development of AZIBs is still hampered due to the lack of suitable cathodes. In this work, the freestanding defective ammonium vanadate@MXene (d-NVO@MXene) hybrid film was synthesized by simple vacuum filtration strategy. Due to the presence of the hierarchical freestanding structure, outstanding MXene conductive networks and abundant oxygen vacancy (in the d-NVO nanoribbons), the d-NVO@MXene hybrid film can not only expose more active sites but also possess outstanding conductivity and kinetics of charge transfer/ion diffusion. When the d-NVO@MXene hybrid film was directly used as the cathode, it displayed a high specific capacity of 498 mAh/g at 0.5 A/g and superior cycling stability performance with near 100 % coulomb efficiency. Furthermore, the corresponding storage mechanism was elucidated by ex situ various characterizations. This work provides new ideas for the development of freestanding vanadium-based cathode materials for AZIBs.

10.
J Urban Health ; 100(4): 696-710, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37535303

RESUMEN

Based on survey data conducted in Guangzhou in 2021, this study employs canonical correlation analysis (CCA) to evaluate the relationship between neighborhood green space, residents' green space use behavior, and their mental health. The results show that compared with the objectively measured accessibility, residents' subjective perceived accessibility of neighborhood green space plays a greater role in promoting green space use behavior and mental health. Meanwhile, the plant diversity, safety, and the number of recreational facilities in a green space can promote the frequency of green space use, improve residents' mental health status and reduce their perceived stress. Although perceived accessibility is more related to green space use behavior than green space quality indicators, green space safety and recreational facilities have many more benefits on mental health than perceived accessibility. In addition, residents' green space use behavior, especially green space visit frequency, can promote mental health and reduce perceived stress.


Asunto(s)
Salud Mental , Parques Recreativos , Humanos , Análisis de Correlación Canónica , Encuestas y Cuestionarios , Satisfacción Personal , Características de la Residencia
11.
J Colloid Interface Sci ; 642: 430-438, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37028156

RESUMEN

Vanadium-based oxides have gained widespread attention as promising cathode materials for aqueous zinc-ion batteries (AZIBs) due to their abundant valences, high theoretical capacity and low cost. However, the intrinsic sluggish kinetics and unsatisfactory conductivity have severely hampered their further development. Herein, a facile and effective defect engineering strategy was developed at room temperature to prepare the defective (NH4)2V10O25·8H2O (d-NHVO) nanoribbon with plenty of oxygen vacancies. Owing to the introduction of oxygen vacancies, the d-NHVO nanoribbon possessed more active sites, excellent electronic conductivity and fast ion diffusion kinetics. Benefiting from these advantages, the d-NHVO nanoribbon as an aqueous zinc-ion battery cathode material exhibited superior specific capacity (512 mAh g-1 at 0.3 A g-1), excellent rate capability and long-term cycle performance. Simultaneously, the storage mechanism of the d-NHVO nanoribbon was clarified via comprehensive characterizations. Furthermore, the pouch battery based on the d-NHVO nanoribbon was fabricated and presented eminent flexibility and feasibility. This work provides a novel thought for simple and efficient development of high- performance vanadium-based oxides cathode materials for AZIBs.

12.
Regen Biomater ; 10: rbad023, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37033324

RESUMEN

Scar-free wound healing is a challenging process due to the excessive deposition of extracellular matrix and collagen. To overcome this issue, hydrogels with superior biochemical and mechanical properties have been used in combination with medicinal compounds as wound dressings. In this study, a novel composite hydrogel consisting of double-crosslinked photocurable hyaluronic acid methacrylate (HAMA) and Laponite (Lap) loaded with bioactive bone morphogenetic protein 4 (BMP4) was developed and thoroughly characterized for its properties such as degradation, morphology, porosity, compression, skin adhesion and load release. The effect of the HAMA/Lap/BMP4 hydrogel was evaluated through both in vitro and in vivo experiments. In the in vivo rabbit ear-scar model, the HAMA/Lap/BMP4 hydrogel dressing was found to reduce scar-related expressions of α-SAM and decrease the ratio of collagen Ι/III in wounded tissue. Additionally, histopathological examination indicated that the HAMA/Lap/BMP4 hydrogel-treated groups exhibited enhanced wound repair and increased levels of collagen maintenance compared to other standard groups, ultimately leading to scarless wound healing. Therefore, this sustained-release photocurable HAMA/Lap/BMP4 hydrogel offers a therapeutic approach for scar-free wound healing.

13.
Artículo en Inglés | MEDLINE | ID: mdl-36141701

RESUMEN

The urban rail transit network provides the possibility for people to shift from car to public transit for travel. This paper clarified the relationships among public transit, accessibility, and equity and studied the impact of rail transit on public transit accessibility that incorporates the measure of travel time and transit fare and the impacts' spatial equity. The results show that rail transit contributes to the similar distribution between high rate of changes of time-based accessibility communities and fare-based accessibility communities, which are located nearby the rail transit lines. The degree of inequity in travel time is higher than the degree in transit fare in two scenarios. Due to the well-connected bus transit in the city center, absolute changes in travel time are slight, while relative changes are high. The rail transit has promoted the improvement of public transit equity in some areas. The difference between the time-based accessibility of Conghua District, northern and southern Baiyun District, Huadu District, Nansha District and southern Panyu District, and other communities is getting smaller, which is conducive to the improvement of spatial equity. The results provide theoretical support for the development of an integrated multimodal public transit system.


Asunto(s)
Transportes , Viaje , China , Humanos , Transportes/métodos
14.
Lancet Reg Health West Pac ; 11: 100143, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34327356

RESUMEN

BACKGROUND: Urogenital Chlamydia trachomatis is the most prevalent bacterial sexually transmitted infection (STI) globally. Reviews suggest high and persistently endemic STI epidemics in low and middle income countries. However population-based prevalence estimates in these settings are less common, underscoring the need for analyses of available data to characterize patterns of disease burden. We identified spatio-temporal clusters and key behavioral, social, or environmental factors contribution to transmission in order to inform the prioritization and targeting of evidence based interventions. METHODS: Using 11 years of data (2006-2016) from the chlamydia case report system of Guangdong, China, we identified county level spatio-temporal hot and cold spots using the Getis-Ord Gi* statistic and discrete Poisson models in SaTScan 9.6. We also estimated associations between observed distribution patterns and area-level demographic, social, and economic factors using quasi-Poisson regression models that controlled for annual counts of certified laboratories to account for fluctuations in location-specific detection capacity. FINDINGS: Cluster analysis indicates an expanding chlamydia epidemic in Guangdong, with cases clustered in regions of greatest economic activity. Greater male-to-female sex ratio (RR, 3.63; 95% CI, 1.41-9.45) and greater urbanicity (RR, 2.44; 95% CI, 1.98-2.99) were predictive of higher chlamydia case occurrence. INTERPRETATION: We found that chlamydia case occurrence in Guangdong province has been accelerating over the past 11 years and that its expansion is tied to indicators of social and economic development. These estimates not only identify high prevalence regions to target but also areas where data gaps potentially remain. The salience of sex ratios and urbanicity may best be understood through the lens of China's modern history of labor migration which has reshaped the gender dynamics and health access landscape of urban China. Future chlamydia control efforts will require a population-based approach focused on reengaging sexually active adults of diverse economic and migratory backgrounds. FUNDING: This was an unfunded study using routinely collected public health data.

15.
J Colloid Interface Sci ; 596: 396-407, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33848745

RESUMEN

The agaric-like anodes of porous carbon decorated with MoO2 nanoparticles (MoO2/C) for reversible Li/Na storage were synthesized via a green and facile bio-inspired route. The uniformly distributed MoO2 nanoparticles, the porous agaric-like carbon matrix and high degree graphitization of carbon materials, effectively mitigated the huge volume changes during cycling and improved the reversible capacity, resulting in the outstanding electrochemical behaviors with excellent rate capability, high capacity and excellent stable long cycling lifespan as anodes for lithium and sodium storage. Especially, the MoO2/C electrodes showed ultralong cycling performance under high current density of 5.0 A g-1, presenting a reversible capacity of 363.2 mAh g-1 after a prolonged 2000-cycles as anodes for Li storage. Meanwhile, the MoO2/C electrodes displayed a super-long cycling lifespan of 3000 cycles with the reversible discharge capacity of 193.5 mAh g-1 at the current density of 5.0 A g-1 for Na storage. Furthermore, the kinetic analysis of MoO2/C-4 electrodes as anodes for Li/Na storage was carried out to further investigate the electrochemical behavior. The ultralong cycling performance under high-density could satisfy the demands of next-generation anode electrodes for Li/Na ion batteries, promoting the commercialization process of MoO2-based materials.

16.
J Transp Geogr ; 95: 103153, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36567951

RESUMEN

Many studies have explored the effects of transportation and population movement on the spread of pandemics. However, little attention has been paid to the dynamic impact of pandemics on intercity travel and its recovery during a public health event period. Using intercity mobility and COVID-19 pandemic data, this study adopts the gradient boosting decision tree method to explore the dynamic effects of the COVID-19 on intercity travel in China. The influencing factors were classified into daily time-varying factors and time-invariant factors. The results show that China's intercity travel decreased on average by 51.35% from Jan 26 to Apr 7, 2020. Furtherly, the COVID-19 pandemic reduces intercity travel directly and indirectly by influencing industry development and transport connectivity. With the spread of COVID-19 and changes of control measures, the relationship between intercity travel and COVID-19, socio-economic development, transport is not linear. The relationship between intercity travel and secondary industry is illustrated by an inverted U-shaped curve from pre-pandemic to post-pandemic, whereas that with tertiary industry can be explained by a U-shaped curve. Meanwhile, this study highlights the dynamic effect of the COVID-19 on intercity mobility. These implications shed light on policies regarding the control measures during public health events that should include the dynamic impact of pandemics on intercity travel.

17.
Biochem Biophys Res Commun ; 534: 727-733, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33190828

RESUMEN

Osteoporosis is a common skeletal complication of diabetes mellitus (DM). The mechanisms underlying the pathophysiology of diabetic osteoporosis are complex. Glycogen synthase kinase-3ß (GSK-3ß) is a widely expressed serine/threonine kinase and associated with both DM and bone metabolism, which arouse our concern. In this study, we established the diabetic mouse model by high-fat diet combined with streptozotocin injection. Decreased bone mass and reduced osteogenesis were observed in femurs of the mice. Besides, we identified that there is an activated expression of GSK3ß in the bone marrow mesenchymal stem cells (BMSCs) of diabetic mice. To explore the link between GSK3ß and diabetic osteoporosis, we exposed BMSCs to a high glucose microenvironment in vitro and discovered that the glucose-induced GSK3ß activation has negative osteogenic effects on BMSCs by suppressing ß-catenin/Tcf7/Ccn4 signaling axis. Inhibition of GSK3ß by specific concentrations of LiCl could reverse the impaired osteogenesis of BMSCs and increase expression of ß-catenin, Tcf7 and Ccn4. Our research indicated that abnormal activation of GSK3ß plays a role in diabetic osteoporosis and might be a potential target to treat diabetic osteoporosis.


Asunto(s)
Diabetes Mellitus Experimental/fisiopatología , Glucosa/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Células Madre Mesenquimatosas/metabolismo , Osteogénesis/fisiología , Animales , Proteínas CCN de Señalización Intercelular/genética , Proteínas CCN de Señalización Intercelular/metabolismo , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/metabolismo , Dieta Alta en Grasa/efectos adversos , Activación Enzimática , Fémur/patología , Fémur/ultraestructura , Factor Nuclear 1-alfa del Hepatocito/genética , Factor Nuclear 1-alfa del Hepatocito/metabolismo , Masculino , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Transducción de Señal , Estreptozocina , beta Catenina/genética , beta Catenina/metabolismo
18.
Sci Total Environ ; 696: 133900, 2019 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-31442729

RESUMEN

CO2 emissions from transportation (TC) are one of the main causes of global climate change. China faces particularly severe pressures and challenges in transportation carbon reduction. Based on the panel data of 30 provinces in China from 2000 to 2015, this study explored the influencing factors and spatial spillover effects of TC by estimating spatial panel data models. It found that China's TC will continue to increase in the future, because the increase in per capita gross domestic product (GDP) is the primary driving force to accelerate the growth of TC, but an increasing proportion of tertiary industry (PTI) in the national economy will help reduce the growth in emissions. Moreover, urban road density (URD) and per capita highway mileage (PHM) are the other two major factors promoting the growth of TC. In contrast, urban population density (UPD) has a negative direct impact on per capita CO2 emissions from transportation (PTC) but also has a larger positive spatial spillover effect, which indicates that these three factors should be properly planned and controlled. Meanwhile, we should actively advocate the development of urban public transport because it plays an important role on reducing TC. The conclusions provide important inspiration and a scientific basis for formulating policies to effectively curb the growth of CO2 emissions in China.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(9): 3053-61, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30085613

RESUMEN

The interactions of Salvianolic acis A (SAA) and Salvianolic acid B (SAB) with insulin were studied by using fluorescence spectroscopy, UV-vis spectroscopy and ATR-FTIR spectroscopy in simulating physiological condition (pH 7.40). The fluorescence quenching of insulin by SAA and SAB were static quenching process. The results of synchronous fluorescence and three-dimensional fluorescence spectra suggested no obvious conformation changes of insulin after SAA or SAB binding. But ATR-FTIR spectra showed that SAA and SAB could change the secondary structures of insulin, of which ß-turns decreased and random coil increased accompanied with α-belices and ß-sheets no clear change. The glucose might influenced the bioactivity of insulin in the SAA-insulin and SAB-insulin systems by changing the binding constants of SAA (or SAB) with insulin and exacerbating the changes of insulin conformation and relative contents of α-belices.

20.
Anal Sci ; 23(4): 463-7, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17420553

RESUMEN

The determination of body fluid acidity using a wireless magnetoelastic pH-sensitive sensor is described. The sensor was fabricated by casting a layer of pH-sensitive polymer on a magnetoelastic ribbon. In response to an externally applied time-varying magnetic field, the magnetoelastic sensor mechanically vibrates at a characteristic frequency that is inversely dependent upon the mass of the pH polymer film, which varies as the film swells and shrinks in response to pH. As the magnetoelastic sensor is magnetostrictive, the mechanical vibrations of the sensor launch magnetic flux that can be detected remotely using a pickup coil. The sensor can be used for direct measurements of body fluid acidity without a pretreatment of the sample by using a filtration membrane. A reversible and linear response was obtained between pH 5.0 and 8.0 with a measurement resolution of pH 0.1 and a slope of 0.2 kHz pH(-1). Since there are no physical connections between the sensor and the instrument, the sensor can be applied to in vivo and in situ monitoring of the physiological pH and its fluctuations.


Asunto(s)
Técnicas Biosensibles/instrumentación , Líquidos Corporales/química , Campos Electromagnéticos , Magnetismo , Técnicas Biosensibles/métodos , Elasticidad , Humanos , Concentración de Iones de Hidrógeno , Polímeros/química
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