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1.
Artigo em Inglês | MEDLINE | ID: mdl-34204658

RESUMO

The difference in glacier surface elevation is a sensitive indicator of climate change and is also important for disaster warning and water supply. In this paper, 25 glaciers on Bogda Mountain, in the eastern Tianshan Mountains, are selected as the study object as they are typical of glaciers in arid or semi-arid areas with importance for water supply. The Repeat Orbit Interferometry (ROI) method is used to survey the surface elevation of these glaciers using Sentinel-1A Radar data from 2017. Using data from the Shuttle Radar Topography Mission (SRTM) and a Digital Elevation Model (DEM), the difference in the glacier surface elevation between 2000 and 2017 is obtained. A scheme to evaluate the accuracy of estimated variations in glacier surface elevation is proposed in this article. By considering the surfaces of lakes in the study region as ideal horizontal planes, the average standard deviation (SD) value of the lake elevation is taken as the error caused by the radar sensor and observing conditions. The SD of the lake elevation is used as an index to evaluate the error in the estimated variation of the glacier surface elevation, and the obtained SD values indicate that the result obtained using the ROI method is reliable. Additionally, the glacier surface elevation variation pattern and a Logarithmic Fitting Model (LFM) are used to reduce the error in high-altitude glacial accumulation areas to improve the estimation of the difference in the glacier surface elevation obtained using ROI. The average SD of the elevation of the 12 lakes is ±2.87 m, which shows that the obtained glacier surface elevations are reliable. This article concludes that, between 2000 and 2017, the surface elevation of glaciers on Bogda Mountain decreased by an average of 11.6 ± 1.3 m, corresponding to an average decrease rate of 0.68 m/a, and glaciers volume decreased by an average of 0.504 km3. Meanwhile, the surface elevations of the lakes increased by an average of 8.16 m. The decrease of glacier surface elevation leads to the expansion of glacial lakes. From the north slope clockwise to the south slope, the glacier elevation variation showed a decreasing trend, and the elevation variation gradually increased from the south slope to the north slope. With the increase of glacier altitude, the variation of glacier surface elevation gradually changed from negative to positive. The findings of this article suggest that the rate of glacier retreat on Bogda Mountain increased from 2000 to 2017.


Assuntos
Camada de Gelo , Lagos , Altitude , Mudança Climática , Abastecimento de Água
2.
Oncol Rep ; 41(1): 543-551, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30542736

RESUMO

Osteosarcoma (OS) is the most common primary malignant bone tumour among adolescents and young adults; however, its molecular pathogenesis has not been completely elucidated. Ubiquitin­specific protease 7 (USP7), a member of the deubiquitinating enzyme family, plays a role in the malignancy process of various cancer types by targeting the key oncoprotein; however, its biological function and mechanism in OS have not been elucidated. The present study demonstrated that USP7 expression in OS tumour tissues was markedly higher than that in the paired surrounding tissues, and high USP7 expression was positively correlated with the TNM stage and metastasis in patients with OS. Next, biological function assays demonstrated that USP7 knockdown markedly inhibited OS cell migration and invasion, whereas USP7 overexpression enhanced it. Notably, USP7 can directly bind with ß­catenin to activate the Wnt/ß­catenin signalling pathway and induce epithelial­mesenchymal transition (EMT) of OS cells. Overall, USP7 overexpression could promote OS cell metastasis by activating the Wnt/ß­catenin signalling pathway by inducing EMT, suggesting that USP7 is a potential therapeutic target for OS.


Assuntos
Neoplasias Ósseas/patologia , Transição Epitelial-Mesenquimal , Osteossarcoma/patologia , Peptidase 7 Específica de Ubiquitina/metabolismo , Adolescente , Adulto , Linhagem Celular Tumoral , Movimento Celular , Criança , Feminino , Técnicas de Silenciamento de Genes , Humanos , Masculino , MicroRNAs/metabolismo , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Ligação Proteica , Peptidase 7 Específica de Ubiquitina/genética , Regulação para Cima , Via de Sinalização Wnt , Adulto Jovem , beta Catenina/metabolismo
3.
Zhongguo Gu Shang ; 23(9): 661-4, 2010 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-20963993

RESUMO

OBJECTIVE: To investigate the medium-term curative effects of locking proximal humerus plate for the treatment of comminuted fractures of proximal humerus, and provide evidences for the clinical practice. METHODS: From August 2005 and April 2008, 23 patients with comminuted fractures of proximal humerus were treated with locking plates, including 12 males and 11 females, aged 27 to 76 years old (averaged 51.5 years old). There were 18 cases of traffic accident injuries, 4 cases of falls injuries, and 1 case injured after heavy pressure. According to Neer classification, 11 cases were three-part fractures, and 12 cases were four-part fractures. Outcomes were assessed with radiography and the Constant-Murley (C-M) shoulder evaluation. RESULTS: All the patients got primary healing of incisions. Twenty-three patients were followed up, and the duration ranged from 17 to 49 months, with an average of 35.25 months. Twenty patients had fracture healing during 4 to 7 months after operation. There was no significant differences among 3, 6 and 12 months after operation in C-M scoring. The average C-M score was (79.85 +/- 17.23) points (38 to 100 points) at the 12th month after operation, 8 cases got an excellent result, 8 good, 5 fair, and 2 poor. In the LPHP plus bone graft group 6 cases got an excellent result, 4 good, 3 fair, and 1 poor; in LPHP fixation group 2 excellent, 4 good, 2 fair,and 1 poor. CONCLUSION: The medium-term curative effect of the locking proximal humerus plate in the treatment of proximal humeral fractures is significant. For the comminuted fractures of proximal humerus combined with osteoporosis and bone defects, bone graft should be performed routinely.


Assuntos
Placas Ósseas , Fraturas Cominutivas/cirurgia , Fraturas do Ombro/cirurgia , Adulto , Idoso , Transplante Ósseo , Feminino , Fixação Interna de Fraturas , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia
4.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 39(4): 523-6, 2008 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-18798484

RESUMO

OBJECTIVE: To construct and identify the recombinant replication deficient adenovirus vector which codes for human Norepinephrine Transporter (hNET) gene by using the method of homogenous recombination in bacteria. METHODS: hNET gene was obtained from the recombinant plasmid pCMV5 via Kpn I + Xba I digestion, and subcloned into E1 deleted expression plasmid pAdtrack-CMV shuttle vector, forming transfer vector pAdtrack-CMV-hNET. Then it was linearized with Pme I followed by homologous recombination with bone plasmid pAdEasy-1 in BJ5183 cells to generate recombinant plasmid Ad-hNET. The DNA of identified Ad-hNET was digested with Pac I and transfected to HEK293 cells by liposome-mediated method to package recombinant adenovirus. The PCR technique was applied to detect the target gene and Western Blotting to verify the expression of hNET. The titre of the Ad-hNET was measured with the aid of green fluorescence protein (GFP) expression after multiplication and purification. RESULTS: By sequencing, it was confirmed that the product was the gene of hNET. PCR test, restriction endonuclease digestion and Western Blotting confirmed the successful construction of the recombinants Ad-hNET. The titre of purified recombinant adenovirus Ad-hNET was 1.2 X 10(10) pfu/mL. CONCLUSION: The recombinant adenovirus with the hNET gene was constructed successfully. It will be helpful for the further investigation of its potentiality to be applied in the tumors targeted therapeutic strategy.


Assuntos
Adenoviridae/genética , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/genética , Proteínas Recombinantes de Fusão/genética , Western Blotting , Linhagem Celular , Vírus Defeituosos/genética , Vetores Genéticos/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Microscopia de Fluorescência , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/biossíntese , Proteínas Recombinantes de Fusão/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
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