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1.
Article in English | MEDLINE | ID: mdl-35162302

ABSTRACT

Roadsides are important urban public spaces where residents are in direct contact with the thermal environment. Understanding the effects of different vegetation types on the roadside thermal environment has been an important aspect of recent urban research. Although previous studies have shown that the thermal environment is related to the type and configuration of vegetation, remote sensing-based technology is not applicable for extracting different vegetation types at the roadside scale. The rapid development and usage of street view data provide a way to solve this problem, as street view data have a unique pedestrian perspective. In this study, we explored the effects of different roadside vegetation types on land surface temperatures (LSTs) using street view images. First, the grasses-shrubs-trees (GST) ratios were extracted from 19,596 street view images using semantic segmentation technology, while LST and normalized difference vegetation index (NDVI) values were extracted from Landsat-8 images using the radiation transfer equation algorithm. Second, the effects of different vegetation types on roadside LSTs were explored based on geographically weighted regression (GWR), and the different performances of the analyses using remotely sensed images and street view images were discussed. The results indicate that GST vegetation has different cooling effects in different spaces, with a fitting value of 0.835 determined using GWR. Among these spaces, the areas with a significant cooling effect provided by grass are mainly located in the core commercial area of Futian District, which is densely populated by people and vehicles; the areas with a significant cooling effect provided by shrubs are mainly located in the industrial park in the south, which has the highest industrial heat emissions; the areas with a significant cooling effect provided by trees are mainly located in the core area of Futian, which is densely populated by roads and buildings. These are also the areas with the most severe heat island effect in Futian. This study expands our understanding of the relationship between roadside vegetation and the urban thermal environment, and has scientific significance for the planning and guiding of urban thermal environment regulation.


Subject(s)
Hot Temperature , Remote Sensing Technology , Cities , Environmental Monitoring , Humans , Temperature , Trees
2.
Biomed Pharmacother ; 122: 109708, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31918279

ABSTRACT

Jiawei Yanghe decoction (JWYHD) is a Traditional Chinese Medicine (TCM) formula for the treatment of osteoarthritis (OA), however the underlying mechanisms of action of JWYHD in OA are not fully explored. This study investigates how JWYHD protects cartilage from degradation via Wnt/ß-catenin signaling pathway. The chondroprotective and anti-inflammatory effect of JWYHD on chondrocytes in vitro and on MIA-induced OA rat model in vivo were investigated. In vitro, JWYHD increased the chondrocyte viability against interleukin (IL)-1ß-induced chondrocytes apoptosis and preserved glycosaminoglycans in the extracellular matrix. JWYHD promoted chondrocyte viability against apoptosis, decreased MMP-3, MMP-13, Caspase-3, Caspase-9 via Wnt/ß-catenin signaling pathway in both IL-1ß-induced and Licl-induced chondrocytes. The qRT-PCR and western blot results showed that mRNA and protein expressions of Wnt signaling pathway related genes ß-catenin and CyclinD1, apoptosis related genes Casapase-3 and Caspase-9, collagen degradation related genes Metalloproteinase (MMP)-3 and MMP-13 were up-regulated, and Col2a1 was down-regulated on IL-1ß-induced chondrocytes. Treatment with JWYHD reversed these effects in a dose-dependent manner. Licl was used as Wnt/ß-catenin signaling pathway activator in chondrocytes to determine the molecular mechanisms. Activation of Wnt signaling pathway by Licl up-regulated ß-catenin, CyclinD1, Axin2, Caspase-3, Caspase-9, MMP-3, MMP-13 and IL-1ß. These effects were blocked by JWYHD treatment. Furthermore, 75 Sprawl-Dawley rats were used to verify the results obtained in vitro. A total of 75 rats were randomly divided into the control group (no MIA-induced OA, received intragastric administration of an equivalent amount of saline), the OA group (MIA-induced OA, received intragastric administration of an equivalent amount of saline), and the JWYHD treatment group (MIA-induced OA, received intragastric administration of an equivalent amount of various concentrations of JWYHD at 1.4/2.7/5.5 g/kg). After 8 weeks of administration, all rats were sacrificed. JWYHD decreased the MIA-induced up-regulation of ß-catenin, CyclinD1, Caspase-3, Caspase-9, MMP-3 and MMP-13 protein expressions in cartilage. It was also demonstrated that JWYHD decreased serum and synovium pro-inflammatory cytokines, IL-1ß, IL-6 and TNF-α in MIA-induced OA rats and ameliorated the cartilage degradation. Histopathological staining, macroscopic observation and micro-CT scan with 3-dimension remodeling showed a cartilage protective effect of JWYHD. In conclusion, JWYHD possess multiple capabilities including preventing chondrocyte apoptosis, preserving integrity of extracellular matrix and anti-inflammatory effect in the treatment of OA both in vitro and in vivo.


Subject(s)
Cartilage, Articular/drug effects , Drugs, Chinese Herbal/pharmacology , Wnt Proteins/metabolism , Wnt Signaling Pathway/drug effects , beta Catenin/metabolism , Animals , Apoptosis/drug effects , Cartilage, Articular/metabolism , Cells, Cultured , Chondrocytes/drug effects , Chondrocytes/metabolism , Extracellular Matrix/metabolism , Female , Inflammation/drug therapy , Inflammation/metabolism , Rats , Rats, Sprague-Dawley
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