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1.
Environ Manage ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750288

RESUMO

Climate change and human activities have significantly influenced soil loss and the soil conservation service, posed threats to regional ecological sustainability. However, the relationships and underlying driving forces between potential soil loss, actual soil loss, and soil conservation service have not been well understood. Utilizing the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model, we evaluated the soil conservation service on the Tibetan plateau from 1990 to 2020. We analyzed the spatial and temporal trends and examined the driving factors using linear regression, Pearson correlation, and random forest regression. The soil conservation service exhibited a complex pattern of increase followed by a decrease, with a turning point around 2010. Soil conservation service and soil loss demonstrated non-trade-off changes. The potential soil loss dominated the spatiotemporal patterns of soil conservation service on the Tibetan Plateau. Climatic factors significantly influenced the spatiotemporal patterns of soil conservation service, with annual precipitation emerging as the dominant driving factor, contributing approximately 20%. However, the impacts of human activities became more pronounced since 2010, and the contribution of vegetation to changes in soil conservation service was increased. The impact of the Normalized Difference Vegetation Index (NDVI) on soil conservation service for the grades I, II, and III increased by 13.19%, 3.08%, and 3.41%, respectively. Conversely, in northern Tibet before 2010 and eastern Three-River-Source after 2010, soil conservation service exhibited an increasing trend driven by both climate factors and human activities. Which indicates that the implementation of ecological restoration measures facilitated vegetation improvement and subsequently reduced actual soil loss. This study provides a scientific basis for resource management, land development strategies, and the formulation of ecological restoration measures on the Tibetan Plateau.

2.
Biomed Rep ; 20(5): 75, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38544959

RESUMO

The present study investigated the inhibitory and neuroprotective effects of Rubia yunnanensis alcohol extract (RY-A) on oxidative stress induced by oxygen-glucose deprivation/reoxygenation (OGD/R) in HT22 cells. In vitro cultured HT22 cells were randomly divided into control, OGD/R, OGD/R + 100 µmol/l edaravone and OGD/R + 10, 20 and 40 µg/ml RY-A groups. Oxygen-sugar deprivation was performed with 10 mmol/l sodium dithionite combined with sugar-free DMEM medium for 2 h, followed by re-glycolization and reoxygenation for 2 h to establish an in vitro OGD/R model. Cell morphology was observed under a phase contrast microscope. Cell survival rate was detected by thiazolyl blue and lactate dehydrogenase and oxidative stress-related indexes were detected by commercial kits. The effects and metabolic alterations of RY-A treatment after OGD/R were evaluated using ultra-high performance liquid chromatography and mass spectrometry. Protein levels were further examined by western blotting. The results showed that cells in the OGD/R group were swollen and lacked protrusions, had significantly reduced viability and had significantly elevated oxidative stress-related indexes of reactive oxygen species, nitric oxide levels and malondialdehyde content and significantly reduced activities of the antioxidant enzymes superoxide dismutase and glutathione peroxidase, compared with controls. Compared with the OGD/R group, the RY-A group had significantly improved cell morphology and significantly increased cell viability and in terms of oxidative stress, exhibited significantly reduced reactive oxygen species, nitric oxide levels and malondialdehyde content, as well as significantly increased superoxide dismutase and glutathione peroxidase activities. Metabolomic analysis identified changes in 20 metabolites, including L-tryptophan, ornithine, eicosapentaenoic acid-d5, isosafrole and xanthine. Metabolomics analysis showed that the pathways affected included those related to phenylalanine, tyrosine and tryptophan biosynthesis, the prolactin signaling pathway and amphetamine addiction. These results suggested that RY-A had significant preventive effects on an in vitro model of cerebral ischemia-reperfusion injury simulated by OGD/R and the mechanism may be related to increased tryptophan content, activation of indoleamine 2,3-dioxygenase enzymes and inhibition of oxidative stress.

3.
Front Microbiol ; 15: 1332108, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38318341

RESUMO

Acinetobacter baumannii is one of the most common multidrug-resistant pathogens causing nosocomial infections. The prevalence of multidrug-resistant A. baumannii infections is increasing because of several factors, including unregulated antibiotic use. A. baumannii drug resistance rate is high; in particular, its resistance rates for tigecycline and polymyxin-the drugs of last resort for extensively drug-resistant A. baumannii-has been increasing annually. Patients with a severe infection of extensively antibiotic-resistant A. baumannii demonstrate a high mortality rate along with a poor prognosis, which makes treating them challenging. Through carbapenem enzyme production and other relevant mechanisms, A. baumannii has rapidly acquired a strong resistance to carbapenem antibiotics-once considered a class of strong antibacterials for A. baumannii infection treatment. Therefore, understanding the resistance mechanism of A. baumannii is particularly crucial. This review summarizes mechanisms underlying common antimicrobial resistance in A. baumannii, particularly those underlying tigecycline and polymyxin resistance. This review will serve as a reference for reasonable antibiotic use at clinics, as well as new antibiotic development.

4.
Biomed Rep ; 20(2): 19, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38170026

RESUMO

Atherosclerosis is a multifactorial vascular disease caused by endothelial dysfunction. Because of adverse reactions to drugs used to treat atherosclerosis. For example, statins, which significantly reduce the burden of atherosclerotic disease, have been associated with muscle toxicity. There is a need to identify novel drugs for the prevention and treatment of atherosclerosis Rubia yunnanensis is a herbs commonly used in Asian countries for its protective effects against cardiovascular diseases. However, the mechanism of action of R. yunnanensis extract in carotid artery atherosclerosis has not been found. The carotid artery is usually used as a site for clinical evaluation of atherosclerosis. The present study aimed to determine the mechanism of action of R. yunnanensis extract in the inhibition of carotid atherosclerosis in apolipoprotein E gene knockout (ApoE-/-) mice. The mechanism of atherosclerosis inhibition was elucidated by detecting the blood lipid level, carotid artery pathology, and the protein expression of PI3K and AKT. The present study demonstrated that ethanol extract of R. yunnanensis reduced lipid levels, intima damage and carotid lipid accumulation and increased p-PI3K/PI3K and p-AKT/AKT protein levels in ApoE-/- mice fed high-fat diet for 12 weeks. It was hypothesized that the effects of R. yunnanensis extract may be achieved by regulation of the phosphatidylinositol-3-kinase/protein kinase B signaling pathway. Ethanol extract of R. yunnanensis decreased carotid atherosclerosis in ApoE-/- mice fed a high-fat diet via the phosphatidylinositol-3-kinase/protein kinase B signaling pathway. Therefore, R. yunnanensis may be a promising option for treating atherosclerosis in the future.

5.
Environ Sci Pollut Res Int ; 30(57): 120663-120682, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37943440

RESUMO

Urbanization is an important factor affecting ecosystem services (ESs) and their trade-offs. However, little is known about the responses of ES trade-offs to urbanization at different scales. Here, the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model was used to evaluate water yield (WY), water purification (WP), carbon storage (CS), and habitat quality (HQ) in Erhai Lake Basin using earth observation data, and the percentage of urban land (PUL), population density (POP), gross domestic product (GDP), and night light index (NLI) were used as urbanization indicators. We quantified the ES trade-offs using the root mean square error and analyzed spatiotemporal changes in urbanization indicators, ESs, and their trade-offs. Finally, we characterized the relationship between urbanization and ES trade-offs using correlation analysis and curve regression at the grid and town scales. From 2000 to 2020, values of PUL/GDP/NLI/POP were high in the south and low in the north; specifically, they were 15, 8, 2, and 0.42 times higher in the south than in the north, respectively. The urban expansion area in the Erhai Basin from 2000 to 2020 resulted in a 123.24% and 77.03% increase in WY and WP, respectively, and a 32.38% and 100% decrease in CS and HQ, respectively. The trade-offs between WY and CS and between WY and HQ increased, and other ES trade-offs decreased. Urbanization was significantly correlated with most ES trade-offs at the grid scale, but not at the town scale. There was a significant positive correlation between all urbanization indicators and the trade-off between CS and WP (p < 0.05), and the magnitude of the correlation increased with scale. The relationship between ES trade-offs and urbanization was mostly U-shaped and inverted U-shaped at the grid scale, but N-shaped and inverted N-shaped at the town scale. This study provides information that could be used for multi-scale urban planning.


Assuntos
Ecossistema , Urbanização , Conservação dos Recursos Naturais/métodos , Lagos , China , Água , Carbono
6.
Infect Drug Resist ; 15: 7317-7325, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36536859

RESUMO

Purpose: To report a rare case of tibial osteomyelitis caused by Mycobacterium aubagnense and its L-form, to systematically review non-tuberculous mycobacteria (NTM) infections of the bones, and to summarize the medication guidelines for infections with NTM and its L-forms. Methods: Case report and literature review. Results: We report a 31-year-old HIV-positive man who developed osteomyelitis caused by M. aubagnense and its L-form. Culture, electron microscopy, polymerase chain reaction assay, and a reversion test confirmed the existence of M. aubagnense. The patient was treated with surgical debridement and a combination of systemic antibiotics, and continued to take antiretroviral treatment. Some clinical improvement was noted shortly after the initiation of this treatment. Resolution of osteomyelitis was achieved after 10 months. We also systematically reviewed cases of NTM osteomyelitis in the PubMed database and compared antibiotic sensitivity between L-forms and their prototype bacteria. We have summarized the treatment regimens for infections of the bone and bone marrow caused by NTM and their L-forms. Conclusion: We have reported the first case of refractory osteomyelitis caused by M. aubagnense and its L-form in a patient with immune deficiency, reviewed the literature on NTM osteomyelitis, and compared the antibiotic sensitivity of L-forms and their prototype bacteria.

7.
Front Cell Infect Microbiol ; 12: 1033427, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339339

RESUMO

Background: Due to the inability to be cultured in vitro, the biological characteristics and pathogenicity of Pneumocystis jirovecii remain unclear. Intestinal microflora disorder is related to the occurrence and development of various pulmonary diseases. This work explores the pathogenesis of pneumocystis pneumonia (PCP) in acquired immune deficiency syndrome (AIDS) patients from a microbiome perspective, to provide better strategies for the diagnosis, treatment, and prevention of PCP. Methods: Subjects were divided into three groups: human immunodeficiency virus (HIV)-infected patients combined with PCP, HIV-infected patients without PCP, and HIV-negative. Stool and bronchoalveolar lavage fluid (BALF) samples were collected, total DNA was extracted, and 16S rRNA high-throughput sequencing was performed using an Illumina MiSeq platform. PICRUSt and BugBase were used to predict microflora functions, and correlation analysis of intestinal and lung bacterial flora was conducted. Results: Compared with the HIV- group, prevotella and another 21 genera in the intestinal microbiome were statistically different in the HIV+ group; 25 genera including Escherichia-Shigella from HIV+PCP+ group were statistically different from HIV+PCP- group. The abundance of Genera such as Porphyromonas was positively or negatively correlated with CD16/CD56+ (µL). Compared with the HIV- group, identification efficiency based on area under the curve (AUC) >0.7 for the HIV+ group identified seven genera in the gut microbiota, including Enterococcus (total AUC = 0.9519). Compared with the HIV+PCP- group, there were no bacteria with AUC >0.7 in the lung or intestine of the HIV+PCP+ group. The number of shared bacteria between BALF and fecal samples was eight species in the HIV- group, 109 species in PCP- patients, and 228 species in PCP+ patients, according to Venn diagram analysis. Changes in various clinical indicators and blood parameters were also closely related to the increase or decrease in the abundance of intestinal and pulmonary bacteria, respectively. Conclusions: HIV infection and PCP significantly altered the species composition of lung and intestinal microbiomes, HIV infection also significantly affected intestinal microbiome gene functions, and PCP exacerbated the changes. The classification model can be used to distinguish HIV+ from HIV- patients, but the efficiency of bacterial classification was poor between PCP+ and PCP- groups. The microbiomes in the lung and gut were correlated to some extent, providing evidence for the existence of a lung-gut axis, revealing a potential therapeutic target in patients with HIV and PCP.


Assuntos
Síndrome da Imunodeficiência Adquirida , Microbioma Gastrointestinal , Infecções por HIV , Microbiota , Pneumonia por Pneumocystis , Humanos , Pneumonia por Pneumocystis/diagnóstico , Pneumonia por Pneumocystis/microbiologia , Síndrome da Imunodeficiência Adquirida/complicações , Infecções por HIV/complicações , RNA Ribossômico 16S/genética , Pulmão/microbiologia
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