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1.
J Environ Manage ; 361: 121218, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38805961

RESUMO

The intricate interaction of natural and anthropogenic factors drives changes in land and water in response to societal demands and climate change. However, there has been insufficient information on the feedback effects in dryland hotspots altered by land change dynamics. This research compared two transboundary inland lakes, the Lake Chad basin (LCB) in Africa and the Aral Sea basin (ASB) in Central Asia, using remote sensing and geographic information system techniques to analyze and quantify present and future land cover dynamics, resilience, and their feedback effects. The study integrated Cellular Automata, Markov Chain, and Multilayer Perceptron models to predict LULC changes up to 2030. Descriptive statistics, ordinary least squares regression, hotspot Gi-Bin, trend analysis, and advanced geostatistical methods were utilized to identify relationships, patterns, magnitudes, and directions of observed changes in the feedback effects. From 2000 to 2030, the analysis unveils intriguing trends, including an increase in cropland from 48% to 51% and a decrease in shrubland from 18% to 15% in the LCB. The grassland increased from 21% to 22%, and the settlement expanded from 0.10 to 0.60% in the ASB. Water bodies remained stable at 1.60 % in LCB, while in ASB, it declined from 3% to 2%. These changes were significantly influenced by population, elevation, and temperature in both basins, with irrigation also playing a significant role in the ASB and slope in LCB. The study further revealed discernible shifts in normalized difference vegetation index, temperature, and precipitation linked to specific land cover conversions, suggesting alterations in surface properties and vegetation health. This study underscores the complex interplay between land cover dynamics, resilience, climate variability, and feedback mechanisms in LCB and ASB.


Assuntos
Mudança Climática , Lagos , África , Sistemas de Informação Geográfica , Conservação dos Recursos Naturais , Ásia
2.
Sensors (Basel) ; 22(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36298114

RESUMO

The development of the smartphone and computer vision technique provides customers with a convenient approach to identify tea species, as well as qualities. However, the prediction model may not behave robustly due to changes in illumination conditions. Fluorescence imaging can induce the fluorescence signal from typical components, and thus may improve the prediction accuracy. In this paper, a tea classification method based on fluorescence imaging and convolutional neural networks (CNN) is proposed. Ultra-violet (UV) LEDs with a central wavelength of 370 nm were utilized to induce the fluorescence of tea samples so that the fluorescence images could be captured. Five kinds of tea were included and pre-processed. Two CNN-based classification models, e.g., the VGG16 and ResNet-34, were utilized for model training. Images captured under the conventional fluorescent lamp were also tested for comparison. The results show that the accuracy of the classification model based on fluorescence images is better than those based on the white-light illumination images, and the performance of the VGG16 model is better than the ResNet-34 model in our case. The classification accuracy of fluorescence images reached 97.5%, which proves that the LED-induced fluorescence imaging technique is promising to use in our daily life.


Assuntos
Redes Neurais de Computação , Imagem Óptica , Chá
3.
Cryobiology ; 99: 46-54, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33524338

RESUMO

Antioxidant defense is essential for animals to cope with homeostasis disruption during hibernation. The present study aimed to investigate the antioxidant defense response of juvenile soft-shelled turtle Pelodiscus sinensis during hibernation and following arousal. Turtle brain, liver, and kidney samples were collected at pre-hibernation (17 °C mud temperature; MT), during hibernation (5.8 °C MT) and after arousal (20.1 °C MT) in the field. Transcript levels of NF-E2-related factor 2 (Nrf2) decreased significantly during hibernation and recovered after arousal in all tissues. Cerebral and nephric copper-zinc superoxide dismutase (Cu/Zn SOD), catalase (CAT), glutathione peroxidase 3 (GPx3) and nephric GPx4 mRNA showed similar changing patterns as Nrf2. Cerebral Mn SOD, GPx1 and nephric GPx1 up-regulated after arousal. Hepatic Cu/Zn SOD, GPx1 and GPx3 mRNA kept stable, except hepatic GPx4 increased during hibernation. Hepatic Mn SOD and CAT increased after arousal. In the GSH system, mRNA levels of glutathione synthetases (GSs) kept stable during hibernation and up-regulated after arousal in most tissues except nephric GS2 mRNA remained unchanged. Gene expressions of glutathione reductase (GR) exhibited a tissue specific changing pattern, while those of glutathione-S-Transferase (GST) shared a similar pattern among tissues: remained stable or down-regulated during hibernation then recovered in arousal. In contrast to these diverse responses in gene expressions, most of the antioxidant enzyme activities maintained high and stable. Overall, no preparation for oxidative stress (POS) strategy was found in enzymatic antioxidant system in P. sinensis juveniles during hibernation, the Chinese soft-shelled turtles were able to stay safe from potential oxidative stress during hibernation by maintaining high level activities/concentrations of the antioxidant enzymes/antioxidants.


Assuntos
Hibernação , Tartarugas , Animais , Antioxidantes , Nível de Alerta , Catalase/genética , Catalase/metabolismo , China , Criopreservação/métodos , Estresse Oxidativo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Tartarugas/genética
4.
J Exp Biol ; 222(Pt 4)2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30630964

RESUMO

The antioxidant defense protects turtles from oxidative stress caused by adverse environment conditions, such as acute thermal fluctuations. However, it remains unclear how these defenses work. The present study examined changes in key enzymes of the enzymatic antioxidant system and the glutathione (GSH) system at both the mRNA and enzyme activity levels during acute cold exposure and recovery in juvenile Chinese soft-shelled turtles, Pelodiscus sinensis Transcript levels of the upstream regulator NF-E2-related factor 2 (Nrf2) were also measured. Turtles were acclimated at 28°C (3 weeks), then given acute cold exposure (8°C, 12 h) and finally placed in recovery (28°C, 24 h). The mRNA levels of cerebral and hepatic Nrf2 and of genes encoding downstream antioxidant enzymes did not change, whereas levels of nephric Nrf2, manganese superoxide dismutase (MnSOD) and glutathione peroxidase 4 (GPx4) mRNA decreased upon cold exposure. During recovery, Nrf2 mRNA remained stable in all three tissues, hepatic Cu/ZnSOD, MnSOD and catalase (CAT) mRNA levels increased, and nephric MnSOD and GPx4 mRNAs did not change from the values during cold exposure. In the GSH system, mRNA levels of most enzymes remained constant during cold exposure and recovery. Unmatched with changes in mRNA level, high and stable constitutive antioxidant enzyme activities were maintained throughout, whereas GPx activity significantly reduced in the kidney during cold exposure, and in liver and kidney during recovery. Our results suggest that the antioxidant defense regulation in response to acute cold exposure in P. sinensis may not be achieved at the transcriptional level, but may rely mainly on high constitutive antioxidant enzyme activities.


Assuntos
Antioxidantes/metabolismo , Temperatura Baixa , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo , Proteínas de Répteis/genética , Tartarugas/fisiologia , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas de Répteis/metabolismo , Tartarugas/genética
5.
Cryobiology ; 81: 43-56, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29475072

RESUMO

Turtles are well known for their stress tolerance, including an ability to deal with temperature extremes or rapid thermal change. To know more about the comprehensive molecular basis of thermal stress responses in turtles, we assessed differentially expressed genes (DEGs) in the brain, liver and kidney of juvenile soft-shelled turtles, Pelodiscus sinensis, after acute cold stress (28 °C-8 °C acute transfer and held for 12 h) and following recovery (back to 28 °C and held for 24 h) by digital gene expression profiling. Selected DEGs were also validated via real-time PCR. We found the fewest DEGs in the brain, only one-tenth of the number seen in liver, indicating a tissue-specific gene expression pattern. The DEGs indicated the potential activation of several important functions in response to cold stress and recovery in P. sinensis. This included response to oxidative stress or regulation of reactive oxygen species metabolism in the brain and liver, cerebral inositol metabolism, hepatic monosaccharide metabolism, hepatic complement system, renal DNA repair mechanisms, and TNF and PI3K-Akt signaling pathways in the kidney. These functions likely responded to cold stress in different tissues of P. sinensis to help minimize or repair cell damage as well as enhance innate immunity. The outcomes of this study provide some fundamental insight into the tissue specific complex mechanisms underlining cold stress responses in the soft-shelled turtle P. sinensis.


Assuntos
Temperatura Baixa/efeitos adversos , Estresse Oxidativo/fisiologia , Estresse Fisiológico/genética , Transcriptoma/genética , Tartarugas/fisiologia , Animais , Perfilação da Expressão Gênica , Análise em Microsséries
6.
Artigo em Inglês | MEDLINE | ID: mdl-27816518

RESUMO

The antioxidant defense system protects turtles from oxidative stress during hibernation. The present study examined changes of the antioxidant enzymes both on mRNA level and enzyme activity level during hibernation of Chinese soft-shelled turtle Pelodiscus sinensis hatchlings. The upstream regulator NF-E2 related factor 2 (Nrf2) mRNA was also measured. Samples were taken at pre-hibernation (17.0°C, Mud temperature (MT)), hibernation (5.8°C, MT) and arousal (20.1°C, MT). Nrf2 exhibited a tissue-specific pattern of expression with a decrease in the brain, slight increase in the liver and heart during hibernation, and significant increase during arousal in all the three tissues. Superoxide dismutase (SOD) mRNA, catalase (CAT) mRNA, and glutathione peroxidase 3 (GPx3) mRNA exhibited a similar pattern as Nrf2 in the brain and liver during the entire hibernation period. Hepatic GPx4 mRNA level increased during hibernation and decreased during arousal, whereas it did not change in the heart. Cerebral SOD and CAT activities kept stable during the experimental period, but GPx activity decreased significantly during hibernation and arousal. Hepatic GPx enzyme activity did not change, whereas those of SOD and CAT exhibited a notable decrease during arousal. Malondialdehyde concentration did not increase during the hibernation process, indicating an effective protection of the antioxidant defense system.


Assuntos
Antioxidantes/metabolismo , Hibernação , Tartarugas/fisiologia , Animais , Encéfalo/enzimologia , Encéfalo/metabolismo , Catalase/genética , Catalase/metabolismo , Malondialdeído/metabolismo , Fator 2 Relacionado a NF-E2/genética , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
7.
Cytotherapy ; 17(10): 1342-52, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26122717

RESUMO

BACKGROUND AIMS: Articular cartilage is an avascular tissue that has limited capacity for self-repair. Mesenchymal stromal cells have been considered as potential candidates for cartilage regeneration. However, clinical results of cartilage formation with the use of these cells need evaluation. We aimed to assess the effect of mesenchymal stromal cell treatment on articular cartilage defects. METHODS: We searched PubMed, Embase and the Cochrane Central Register of Controlled Trials with key words including "cartilage," "clinical trial," "mesenchymal," "stromal" and "stem cell" up to December 3, 2014. We selected the controlled trial that used treatment with mesenchymal stromal cells on cartilage injury compared with other treatment. We assessed the results of the meta-analysis by means of the error matrix approach. The outcome measures were ranked as comprehensive evaluation index, highest relevance; unilateral evaluation index, medial relevance; and single evaluation index, lowest relevance. RESULTS: Eleven trials assessing 558 patients were included in the meta-analysis. Stem cell treatment significantly improved the American Orthopedic Foot and Ankle Society Scale (Standard Mean Difference, SMD, 0.91; 95% confidence interval [CI], 0.52 to 1.29). The Osteo-Arthritis Outcome Score was also significantly improved in stem cell treatment (SMD, 2.81; 95% CI, 2.02 to 3.60). Other comprehensive evaluation indexes, such as the American Knee Society Knee Score System (SMD -0.12, 95% CI, -1.02 to 0.78), the Hospital for Special Surgery Knee Rating Scale (SMD, 0.24, 95% CI, -0.56 to 1.05) and the International Knee Documentation Committee (SMD, -0.21; 95% CI, -0.77 to 0.34), appeared to have no significant differences by use of stem cell and other treatments. Overall, there was no obvious advantage regarding the application of stem cells to treat cartilage injury, compared with other treatments. CONCLUSIONS: In conclusion, assessment of the comprehensive evaluation index indicated that there were no significant differences after stem cell treatment. However, assessment of clinical symptoms and cartilage morphology showed significant improvement after stem cell treatment.


Assuntos
Cartilagem Articular/fisiologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Osteoartrite do Joelho/terapia , Regeneração , Feminino , Humanos , Articulação do Joelho/patologia , Masculino , Osteoartrite do Joelho/patologia , Osteocondrite/terapia , Avaliação de Resultados em Cuidados de Saúde
8.
Appl Opt ; 54(28): E159-64, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26479647

RESUMO

The major factors of an illuminative environment are a high rendering index and uniformity. The natural light illumination system (NLIS) is used to guide sunlight for indoor illumination. The NLIS consists of three subsystems: collecting, transmitting, and emitting. Nowadays, a variety of light emitters are available for different illuminative environments. This paper proposes a linear microstructure to diffuse parallel light for indoor illumination. To increase uniformity and promote the illuminative area, the light emitter includes two microstructures for the distribution of light. Finally, the proposed light emitter gives illuminance uniformity and efficiency of 0.55% and 74.18%, respectively.

9.
Appl Opt ; 54(28): E165-70, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26479648

RESUMO

This research presents a novel design of the collimator, which uses total internal reflection (TIR), convex, and concave lenses for the natural light illumination system (NLIS). The concept of the NLIS is to illuminate building interiors with natural light, which saves energy consumption. The TIR lens is used to collimate the light, and convex and concave lenses are used to converge the light to the required area. The results have shown that the efficiency in terms of achieving collimated light using the proposed collimator at the output of the light collector is better than that of a previous system without a collimator.

10.
Artigo em Inglês | MEDLINE | ID: mdl-25645296

RESUMO

Intense temperature change often leads to increased oxidative stress in many animals with a few exceptions, including the turtle. To date, little is known about the mechanism of protective antioxidative defenses in turtles during acute temperature change, specifically the role that the antioxidant ascorbic acid (AA) plays. In this study, Chinese soft-shelled turtles (Pelodiscus sinensis) were initially acclimated at 28°C (3 wks), exposed to acute cold condition (8°C, 8 h) and finally placed in recovery (28°C, 24 h). L-Gulonolactone oxidase (GLO) mRNA exhibited a stable transcription pattern during the intense thermal fluctuation. GLO activity also remained stable, which validated the mRNA expression pattern. The similar Q10 values for GLO activity in the different treatment groups at incubation temperatures of 28°C and 8°C indicated that the GLO activity response to thermal change exhibited a temperature-dependent enzymatic kinetic characteristic. The AA storage was tissue-specific as well as the AA re-supply in the recovery period, with brain as the priority. Despite the insufficient transport during cold exposure, the plasma AA reservoir greatly contributed to the redistribution of AA during recovery. Depending on the prominent GLO activity, the high level of tissue-specific AA storage and the extraordinary plasma AA transport potential, the Chinese soft-shelled turtle endured severe thermal fluctuations with no apparent oxidative stress. However, the significant decrease in AA concentration in the brain tissue during acute cold exposure suggested that such a strategy may not be sufficient for prolonged cold exposure.


Assuntos
Ácido Ascórbico/fisiologia , Temperatura Baixa , Estresse Fisiológico , Tartarugas/fisiologia , Animais , Expressão Gênica , L-Gulonolactona Oxidase/genética , L-Gulonolactona Oxidase/metabolismo , Estresse Oxidativo , RNA Mensageiro/genética
11.
Front Surg ; 10: 1120273, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37139192

RESUMO

Background: This study aimed to demonstrate that dual-mobility cup total hip arthroplasty (DMC-THA) can significantly improve the quality of life (QOL) of elderly femoral neck fracture patients with severe neuromuscular disease in unilateral lower extremities due to stroke hemiplegia compared to internal fixation (IF). Methods: Fifty-eight cases of severe neuromuscular disease in the unilateral lower extremities with muscle strength < grade 3/5 due to stroke were retrospectively examined From January 2015 to December 2020. Then, patients were divided into DMC and IF groups. The QOL was examined using the EQ-5D and SF-36 outcome measures. The physical and mental statuses were assessed using the Barthel Index (BI) and e Fall Efficacy Scale-International (FES-I), respectively. Results: Patients in the DMC group had higher BI scores than those in the IF group at different time point. Regarding mental status, the FES-I mean score was 42.1 ± 5.3 in the DMC group and 47.3 ± 5.6 in the IF group (p = 0.002). For the QOL, the mean SF-36 score was 46.1 ± 18.3 for the health component and 59.5 ± 15.0 for the mental component in the DMC group compared to 35.3 ± 16.2 (p = 0.035), and 46.6 ± 17.4 (p = 0.006) compared to the IF group. The mean EQ-5D-5L values were 0.733 ± 0.190 and 0.303 ± 0.227 in the DMC and IF groups (p = 0.035), respectively. Conclusion: DMC-THA significantly improved postoperative QOL compared to IF in elderly patients with femoral neck fractures and severe neuromuscular dysfunction in the lower extremity after stroke. The improved outcomes were related to the enhanced early, rudimentary motor function of patients.

12.
Front Neurorobot ; 17: 1331427, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38288312

RESUMO

Insulators play a pivotal role in the reliability of power distribution networks, necessitating precise defect detection. However, compared with aerial insulator images of transmission network, insulator images of power distribution network contain more complex backgrounds and subtle insulator defects, it leads to high false detection rates and omission rates in current mainstream detection algorithms. In response, this study presents ID-YOLOv7, a tailored convolutional neural network. First, we design a novel Edge Detailed Shape Data Augmentation (EDSDA) method to enhance the model's sensitivity to insulator's edge shapes. Meanwhile, a Cross-Channel and Spatial Multi-Scale Attention (CCSMA) module is proposed, which can interactively model across different channels and spatial domains, to augment the network's attention to high-level insulator defect features. Second, we design a Re-BiC module to fuse multi-scale contextual features and reconstruct the Neck component, alleviating the issue of critical feature loss during inter-feature layer interaction in traditional FPN structures. Finally, we utilize the MPDIoU function to calculate the model's localization loss, effectively reducing redundant computational costs. We perform comprehensive experiments using the Su22kV_broken and PASCAL VOC 2007 datasets to validate our algorithm's effectiveness. On the Su22kV_broken dataset, our approach attains an 85.7% mAP on a single NVIDIA RTX 2080ti graphics card, marking a 7.2% increase over the original YOLOv7. On the PASCAL VOC 2007 dataset, we achieve an impressive 90.3% mAP at a processing speed of 53 FPS, showing a 2.9% improvement compared to the original YOLOv7.

13.
Foods ; 12(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37107517

RESUMO

The larvae of Clanis bilineata tsingtauica, a special species of Chinese edible insect, are of great nutritional, medicinal and economic value to humans. This study aimed to clarify the effect of different soybean varieties (Guandou-3 (G3), Ruidou-1 (R1), September cold (SC)) on the nutritional quality and feeding selection behavior of C. bilineata tsingtauica larvae. The results showed that soybean isoleucine (Ile) and phenylalanine (Phe) were positively correlated with larval host selection (HS) and protein content. The order of soybean plants selected by C. bilineata tsingtauica larvae was R1 > SC > G3, and they selected R1 significantly higher than SC and G3 by 50.55% and 109.01%, respectively. The protein content of the larvae fed on R1 was also the highest among the three cultivars. In addition, a total of 17 volatiles belonging to 5 classes were detected from soybeans: aldehydes, esters, alcohols, ketones, and heterocyclic compounds. Pearson's analysis showed that soybean methyl salicylate was positively correlated with larval HS and their protein content, and soybean 3-octenol was negatively correlated with larval HS and their palmitic acid content. In conclusion, C. bilineata tsingtauica larvae are more adapted to R1 than to the other two soybean species. This study provides a theoretical basis for the production of more protein-rich C. bilineata tsingtauica in the food industry.

14.
Front Physiol ; 14: 1093713, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846329

RESUMO

Good exploitation and utilization of edible insects can effectively alleviate global food security crisis in years. The study on diapause larvae of Clanis bilineata tsingtauica (DLC) was conducted to explore how gut microbiota regulate the nutrients synthesis and metabolism of edible insects. The results showed that C. bilineata tsingtauica maintained a total and stable nutrition levels at early phase of diapause. The activity of instetinal enzymes in DLC fluctuated markedly with diapause time. Additionally, Proteobacteria and Firmicutes were the predominant taxa, and TM7 (Saccharibacteria) was the marker species of gut microbiota in DLC. Combined the gene function prediction analysis with Pearson correlation analysis, TM7 in DLC was mainly involved in the biosynthesis of diapause-induced differential fatty acids, i.e., linolelaidic acid (LA) and tricosanoic acid (TA), which was probably regulated by changing the activity of protease and trehalase, respectively. Moreover, according to the non-target metabolomics, TM7 might regulate the significant differential metabolites, i.e., D-glutamine, N-acetyl-d-glucosamine and trehalose, via the metabolism of amino acid and carbohydrate pathways. These results suggest that TM7 increased LA and decreased TA via the intestinal enzymes, and altered intestinal metabolites via the metabolism pathways, maybe a key mechanism for regulating the nutrients synthesis and metabolisms in DLC.

15.
Artigo em Inglês | MEDLINE | ID: mdl-36498005

RESUMO

As a principal source of long-chain omega-3 fatty acids (3FAs), which provide vital health benefits, fish consumption also comes with the additional benefit of being rich in diverse nutrients (e.g., vitamins and selenium, high in proteins and low in saturated fats, etc.). The consumption of fish and other seafood products has been significantly promoted universally, given that fish is an important part of a healthy diet. However, many documents indicate that fish may also be a potential source of exposure to chemical pollutants, especially mercury (Hg) (one of the top ten chemicals or groups of chemicals of concern worldwide), and this is a grave concern for many consumers, especially pregnant women, as this could affect their fetuses. In this review, the definition of Hg and its forms and mode of entrance into fish are introduced in detail and, moreover, the bio-accumulation of Hg in fish and its toxicity and action mechanisms on fish and humans, especially considering the health of pregnant women and their fetuses after the daily intake of fish, are also reviewed. Finally, some feasible and constructive suggestions and guidelines are recommended for the specific group of pregnant women for the consumption of balanced and appropriate fish diets in a rational manner.


Assuntos
Mercúrio , Animais , Feminino , Humanos , Gravidez , Mercúrio/análise , Alimentos Marinhos/análise , Contaminação de Alimentos/análise , Peixes , Dieta
16.
Gene ; 830: 146465, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35427733

RESUMO

OBJECTIVE: This study aimed to investigate the effect of aerobic exercise combined with glucosamine (OTL) on the apoptosis of chondrocytes of rabbit knee osteoarthritis (KOA) by affecting the expression of TRPV5. METHODS: After the KOA white rabbit model was established, aerobic training and OTL treatment were performed, then the model joints were evaluated by Mankin, HE staining was used to observe the pathological changes of articular cartilage, TUNEL and immunohistochemistry were used to detect chondrocyte apoptosis. Knee chondrocytes were isolated and identified by Alcian Blue and type II collagen fiber staining. The cells were treated with iodoacetic acid (MIA) to simulate osteoarthritis in vitro, and then the effect of TRPV5 on apoptosis was detected by flow cytometry, in addition, apoptosis-related proteins and TRPV5 were detected by western blotting and qRT-PCR. RESULTS: Both aerobic exercise and OTL treatment could significantly reduce the Mankin score of KOA model, and could effectively inhibit chondrocyte apoptosis in the KOA model, and inhibit the expression of caspase 3 and caspase 9 in the KOA model. TRPV5 expression was significantly increased in the model, while both aerobic exercise and OTL could reverse its expression. The low-expression of TRPV5 significantly reversed the role of MIA in promoting apoptosis and apoptosis-related proteins of knee chondrocytes, while overexpressing TRPV5 promoted MIA-induced apoptosis and apoptosis-related proteins. CONCLUSION: Aerobic exercise combined with glucosamine hydrochloride capsules inhibited the apoptosis of chondrocytes in rabbit KOA by affecting the expression of TRPV5.


Assuntos
Cartilagem Articular , Osteoartrite do Joelho , Animais , Apoptose , Cápsulas/metabolismo , Cápsulas/farmacologia , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Glucosamina/metabolismo , Glucosamina/farmacologia , Osteoartrite do Joelho/tratamento farmacológico , Osteoartrite do Joelho/metabolismo , Coelhos
17.
Integr Zool ; 17(4): 581-595, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34713576

RESUMO

The antioxidant defense system is essential for animals to cope with homeostasis disruption and overcome oxidative stress caused by adverse environmental conditions such as hypoxia. However, our understanding of how this system works in subterranean rodents remains limited. In this study, Brandt's vole Lasiopodomys brandtii was exposed to normoxia (21% O2 ) or hypoxia (mild or severe hypoxia: 10% or 5% O2 ) for 6 h. Changes in key enzymes of the classic enzymatic antioxidant system at both mRNA and enzyme activity levels, and tissue antioxidant levels of the low-molecular-weight antioxidant system were determined in brain, liver, and kidney. Transcript levels of the upstream regulator NF-E2-related factor 2 (Nrf2) were also measured. We found that the mRNA expression of Nrf2 and its downstream antioxidant enzyme genes in L. brandtii were relatively conserved in response to hypoxia in most tissues and genes tested, except in the liver. Hepatic Nrf2, Cu/Zn SOD, GPx1, and GPx3 levels were significantly upregulated in response to mild hypoxia, whereas Mn SOD level decreased significantly in severe hypoxia. Unmatched with changes at the RNA level, constitutively high and relatively stable antioxidant enzyme activities were maintained throughout. For the low-molecular-weight antioxidant system, an abrupt increase of cerebral ascorbic acid (AA) levels in hypoxia indicated a tissue-specific antioxidant response. Although hypoxia did not cause significant oxidative damage in most tissues tested, the significant decrease in antioxidant enzyme activities (GPX and GR) and increase in lipid peroxidation in the kidney suggest that prolonged hypoxia may pose a critical threat to this species.


Assuntos
Antioxidantes , Fator 2 Relacionado a NF-E2 , Animais , Antioxidantes/metabolismo , Arvicolinae/fisiologia , Hipóxia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , RNA Mensageiro
18.
Injury ; 53(8): 2754-2762, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35760641

RESUMO

BACKGROUND: Consensus regarding the optimal amount of bone cement and vertebral height in the treatment of osteoporotic vertebral compression fractures (OVCFs) is lacking. Our purpose was to explore the optimal amount of bone cement and vertebral height in OVCF after percutaneous vertebral augmentation (PVA). METHODS: A three-dimensional finite element model of the L1-L3 segments was constructed from CT scans of aging osteoporosis patients. Four different postoperative vertebral height models were simulated according to Genant semiquantitative grades 0, 1, 2, and 3. The volume of bone cement filling ranged from 3 ml to 6 ml. These models evaluated the von Mises stress of injured vertebral bodies, adjacent vertebral bodies and intervertebral discs under flexion, extension, left flexion, and right flexion after PVA. RESULTS: When the bone cement content was held constant, as the height of the vertebral body decreased, the stress of the L2 vertebral body decreased during left flexion and right flexion, but the stress of the L2 vertebral body increased and decreased during flexion and extension. As the height of the vertebral body decreased, the stress of the L1-L2 intervertebral disc increased. There was no significant change in the stress of other adjacent vertebrae or intervertebral discs. When the Genant grade was 0, 1, or 2 (3 ml and 4 ml), the stress of the overall vertebral body was closest to normal. CONCLUSIONS: When the height of the vertebral body is restored to the same height, a bone cement filling volume of 3 ml to 6 ml is suitable and will not produce a significant change in the stress of the vertebral body or adjacent vertebral body. As vertebral body height was lost, it may promote the degeneration of the intervertebral disc above the injury vertebrae after PVA. It is appropriate for the height of the vertebral body to return to Genant grade 0 or Genant grade 1 after surgery. When the height of the vertebral body has Genant grade 2 status, it was best to use 3 ml to 4 ml of bone cement filling. Therefore, when treating OVCFs, clinicians do not need to pursue complete reduction of the vertebral body. It is also important to verify the biomechanics results in clinical studies.


Assuntos
Fraturas por Compressão , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Cimentos Ósseos/uso terapêutico , Análise de Elementos Finitos , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/cirurgia , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/lesões , Vértebras Lombares/cirurgia , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia
19.
Zool Res ; 43(4): 497-513, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35585802

RESUMO

Oxygen is essential for most life forms. Insufficient oxygen supply can disrupt homeostasis and compromise survival, and hypoxia-induced cardiovascular failure is fatal in many animals, including humans. However, certain species have adapted and evolved to cope with hypoxic environments and are therefore good models for studying the regulatory mechanisms underlying responses to hypoxia. Here, we explored the physiological and molecular responses of the cardiovascular system in two closely related hypoxia-adapted species with different life histories, namely, Qinghai voles ( Neodon fuscus) and Brandt's voles ( Lasiopodomys brandtii), under hypoxic (10% O 2 for 48 h) and normoxic (20.9% O 2 for 48 h) exposure. Kunming mice ( Mus musculus) were used for comparison. Qinghai voles live in plateau areas under hypoxic conditions, whereas Brandt's voles only experience periodic hypoxia. Histological and hematological analyses indicated a strong tolerance to hypoxia in both species, but significant cardiac tissue damage and increased blood circulation resistance in mice exposed to hypoxia. Comparative transcriptome analysis revealed enhanced oxygen transport efficiency as a coping mechanism against hypoxia in both N. fuscus and L. brandtii, but with some differences. Specifically, N. fuscus showed up-regulated expression of genes related to accelerated cardiac contraction and angiogenesis, whereas L. brandtii showed significant up-regulation of erythropoiesis-related genes. Synchronized up-regulation of hemoglobin synthesis-related genes was observed in both species. In addition, differences in cardiometabolic strategies against hypoxia were observed in the rodents. Notably, M. musculus relied on adenosine triphosphate (ATP) generation via fatty acid oxidation, whereas N. fuscus shifted energy production to glucose oxidation under hypoxic conditions and L. brandtii employed a conservative strategy involving down-regulation of fatty acid and glucose oxidation and a bradycardia phenotype. In conclusion, the cardiovascular systems of N. fuscus and L. brandtii have evolved different adaptation strategies to enhance oxygen transport capacity and conserve energy under hypoxia. Our findings suggest that the coping mechanisms underlying hypoxia tolerance in these closely related species are context dependent.


Assuntos
Arvicolinae , Hipóxia , Animais , Arvicolinae/fisiologia , Ácidos Graxos , Glucose , Hipóxia/veterinária , Camundongos , Oxigênio
20.
Microorganisms ; 9(8)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34442797

RESUMO

Cyanobacteria in the genus Microcystis are dominant components of many harmful algal blooms worldwide. Their pelagic-benthic life cycle helps them survive periods of adverse conditions and contributes greatly to their ecological success. Many studies on Microcystis overwintering have focused on benthic colonies and suggest that sediment serves as the major inoculum for subsequent summer blooms. However, the contemporaneous overwintering pelagic population may be important as well but is understudied. In this study, we investigated near-surface and near-bottom pelagic population dynamics of both microcystin-producing Microcystis and total Microcystis over six weeks in winter at Dog Lake (South Frontenac, ON, Canada). We quantified relative Microcystis concentrations using real-time PCR. Our results showed that the spatiotemporal distribution of overwintering pelagic Microcystis was depth dependent. The abundance of near-bottom pelagic Microcystis declined with increased depth with no influence of depth on near-surface Microcystis abundance. In the shallow region of the lake (<10 m), most pelagic Microcystis was found near the lake bottom (>90%). However, the proportion of near-surface Microcystis rose sharply to over 60% as the depth increased to approximately 18 m. The depth-dependent distribution pattern was found to be similar in both microcystin-producing Microcystis and total Microcystis. Our results suggest the top of the water column may be a more significant contributor of Microcystis recruitment inoculum than previously thought and merits more attention in early CHAB characterization and remediation.

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