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2.
Sci Data ; 11(1): 310, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521796

RESUMO

Wetlands play a key role in maintaining ecological balance and climate regulation. However, due to the complex and variable spectral characteristics of wetlands, there are no publicly available global 30-meter time-series wetland dynamic datasets at present. In this study, we present novel global 30 m annual wetland maps (GWL_FCS30D) using time-series Landsat imagery on the Google Earth Engine platform, covering the period of 2000-2022 and containing eight wetland subcategories. Specifically, we make full use of our prior globally distributed wetland training sample pool, and adopt the local adaptive classification and spatiotemporal consistency checking algorithm to generate annual wetland maps. The GWL_FCS30D maps were found to achieve an overall accuracy and Kappa coefficient of 86.95 ± 0.44% and 0.822, respectively, in 2020, and show great temporal variability in the United States and the European Union. We expect the dataset would provide vital support for wetland ecosystems protection and sustainable development.


Assuntos
Ecossistema , Áreas Alagadas , Clima , Monitoramento Ambiental
3.
Ying Yong Sheng Tai Xue Bao ; 35(2): 469-479, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38523105

RESUMO

Determining priority areas for territorial ecological restoration in the arid region of Northwest China based on the holistic protection and systematic governance is an important measure to build solid national ecological security barrier and promote the construction of territorial ecological civilization. Taking Zhangye City, a typical arid area city in Northwest China, as an example, we constructed the research framework of "ecological network-ecological sensitivities-ecological degradation" from two aspects of internal defects and external threats of ecological networks by using circuit theory and assessment methods of ecological service function importance, ecological sensitivity, and ecological degradation. We then identified the priority areas of territorial ecological restoration in northwest arid region and put forward the restoration strategies. The results showed that the priority areas of ecological restoration in Zhangye City were concentrated in the artificial shelterbelt along rivers and the plain-desert-oasis transition zone with fragile ecology and strong human interference. The ecological network of the study area included 39 ecological sources and 99 ecological corridors, and the highly sensitive and degraded areas were 1595.40 and 6.65 km2. Based on the internal defects and external threats of the ecological network, we identified 31 ecological pinch points, 7 obstacle points, and 753.56 km2 ecological source areas in the territorial spatial ecological restoration priority area. These areas were related to the connectivity of the ecological network internally and the stability maintenance of the ecosystem outwards, and were the areas to restoration in the future. Following the concept of overall protection and system restoration of territorial space, we put forward the idea of territorial space restoration by integrating internal defects and external threats of ecological network, which could provide scientific decision-making basis for comprehensive ecosystem management and territorial optimization of Zhangye City.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , Rios , Cidades , China , Ecologia
4.
Front Public Health ; 11: 1301752, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38283286

RESUMO

Background: Geriatric diseases (e.g., chronic diseases and geriatric syndromes) may result in impaired physical performance and a decline in the quality of life. The results of previous studies reported the positive effects of comprehensive community-based rehabilitation (CBR) services on physical and social functioning and psychosocial wellbeing. However, to provide adequate and personalised rehabilitation services, it is essential to understand the needs of the older adults population. There have been no studies on the need for CBR in older adults populations that consider their heterogeneity. Therefore, high-quality studies are required to recognise the heterogeneity and latent classes of CBR needs in older adults population groups. This study aims to identify the heterogeneity of the rehabilitation needs of older adults in the community and explore whether older adults with similar characteristics have similar needs through a cross-sectional survey and latent class analysis (LCA) to provide support for personalised rehabilitation services. Methods: The study is structured into four phases. The first phase will focus on constructing a comprehensive questionnaire to assess rehabilitation needs. In the second phase, a pilot study will be conducted to evaluate the reliability and validity of the completed questionnaire. This step ensures the robustness of the instrument for data collection. The third phase will involve cross-sectional surveys using the finalised questionnaires to collect the necessary data from the targeted population. The fourth phase will focus on conducting LCA to determine the CBR needs of the older adult population. Discussion: The results of this study will provide novel and critical information for a better understanding of the rehabilitation needs, potential categories, and influencing factors of older adults in the community. The study will be conducted in Guizhou Province in western China, where economic and social development is relatively low, and the results will inform and benefit other regions and developing countries facing similar challenges. However, because of the complete social security and rehabilitation service systems in developed areas, our research results may not fully reflect the situation in these areas. Future studies may need to be conducted in places with different levels of social development. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=191398, ChiCTR2300071478.


Assuntos
Serviços de Saúde Comunitária , Avaliação das Necessidades , Reabilitação , Estudos Transversais , Análise de Classes Latentes , Projetos Piloto , Qualidade de Vida , Reprodutibilidade dos Testes , Humanos , Idoso
5.
Sci Data ; 8(1): 243, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34545093

RESUMO

Numerous validation efforts have been conducted over the last decade to assess the accuracy of global leaf area index (LAI) products. However, such efforts continue to face obstacles due to the lack of sufficient high-quality field measurements. In this study, a fine-resolution LAI dataset consisting of 80 reference maps was generated during 2003-2017. The direct destructive method was used to measure the field LAI, and fine-resolution LAI images were derived from Landsat images using semiempirical inversion models. Eighty reference LAI maps, each with an area of 3 km × 3 km and a percentage of cropland larger than 75%, were selected as the fine-resolution validation dataset. The uncertainty associated with the spatial scale effect was also provided. Ultimately, the fine-resolution reference LAI dataset was used to validate the Moderate Resolution Imaging Spectroradiometer (MODIS) LAI product. The results indicate that the fine-resolution reference LAI dataset builds a bridge to link small sampling plots and coarse-resolution pixels, which is extremely important in validating coarse-resolution LAI products.

6.
Front Oncol ; 11: 646527, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33842360

RESUMO

Hepatocellular carcinoma is a highly malignant and lethal tumor. In addition to surgery, immunotherapy is currently a more effective treatment for hepatocellular carcinoma. The tumor immune microenvironment (TIME) largely determines the efficacy of cancer immunotherapy. Based on the universal targeting of TIME modulators in clinical treatment, TIME modulators are promising targets for tumor immunotherapy. We investigated the effect of a double gene expression vector (recombinant galactose-terminal glycol-poly-L-lysine coupled MIP-3α-FL) on dendritic cells (DCs) regulation within the TIME of mice with liver cancer. H22 cells were transfected with a recombinant MIP-3α-FL plasmid to induce DCs differentiation and chemotaxis. The effects of transfection were investigated by flow cytometry following the modified Boyden's method. Cytokine-induced killer (CIK) cells co-culture revealed changes in the antigen presentation ability of DCs. Further, tumor-bearing mice were injected with the recombinant double gene vector via the tail vein. We compared the survival time, tumor volume, weight of the mice, as well as the number and phenotype of tumor-infiltrating DCs (TIDCs) between groups. The supernatant of transfected H22 cells promoted the phenotypic maturation of DCs, enhancing their chemotaxis. Further, treated DCs promoted the cytokine secretion and killing ability of CIK cells. The survival time of mice injected with the double gene vector was significantly prolonged, while their tumor weight and volume were relatively reduced. Flow cytometry revealed that the number of TIDCs (as well as CD80 and CD86 expression) in the MouseMIP-3α-FL group, were significantly higher than in the control group. The combination of MIP-3α and FL can significantly promote DCs aggregation, maturation, and enhance their antigen presentation ability. The coupling of the double gene vector with glycosylated polylysine can improve the precise targeting of the liver and inhibit tumor growth in vivo, providing a novel approach for immune therapy in liver cancer.

7.
DNA Cell Biol ; 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33085544

RESUMO

The carbon catabolite repressor 4-negative on TATA (CCR4-NOT) complex, abbreviated CNOT, has deadenylation and 3'-5' exonuclease activity, mediates deadenylation in the degradation of RNA, initiates the exonuclease degradation pathway, and participates in tumor gene regulation. CNOT proteins comprise a family of global transcriptional regulators that are evolutionarily conserved in eukaryotic cells. Several subunit types of the CNOT complex have been discovered; however, little is known about the role of different subunits in tumorigenesis and development. We observed overexpression of CNOT1-11 in liver cancer and correlations with clinicopathological characteristics. The expression of some CNOTs subunits was associated with histological grades, lymph node metastasis, and tumor stages in patients with hepatocellular carcinoma (HCC). Our data suggested that some CNOTs can be used as predictors of poor prognosis in HCC patients. At the same time, we conducted an analysis of CNOTs mutations in HCC patients. Moreover, we selected CNOT6, CNOT10, and CNOT11 for protein interaction network analysis and Gene Ontology enrichment analysis to investigate their related biological processes and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Finally, the results of western blot and quantitative reverse transcription-PCR (qRT-PCR) experiments were consistent with the database findings. Results of this study suggest that CNOT6, CNOT10, and CNOT11, acting as regulators of transcription, may play an important role in the development of HCC and may serve as biological markers in the diagnosis and prognosis of HCC.

8.
Oncol Lett ; 19(1): 211-220, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31897132

RESUMO

Pancreatic cancer is characterized by the absence of early specific clinical symptoms, accompanied with rapid metastasis and invasion. It is one of the most prevalent types of cancer and more importantly, one of the most common types of malignant cancer with the highest mortality rate of all cancer types. The heparanase (HPA)/syndecan-1 (SDC1) axis has been reported to promote tumor growth, invasion, metastasis and angiogenesis in a variety of cancer types; however, studies into the role and mechanism of the HPA/SDC1 axis in pancreatic cancer are limited. The present study aimed to investigate the biological function and clinical significance of the HPA/SDC1 axis in pancreatic cancer. The results demonstrated that HPA is elevated in pancreatic cancer tissues and cell lines, and that its high expression was associated with poor prognosis. HPA was revealed to mediate an increase in fibroblast growth factor 2 (FGF2) expression by upregulating the expression of SDC1. Conversely, silencing HPA mediated the suppression of FGF2 expression. Furthermore, upregulated FGF2 was observed to increase the expression of downstream Palladin proteins by activating the PI3K/Akt signaling pathway and also lead to the activation of epithelial-mesenchymal transition (EMT). Subsequently, EMT was found to promote the migration and invasion of pancreatic cancer cells. In summary, the HPA/SDC1 axis was revealed to serve an important role in the regulation of FGF2, and was found to promote the invasion and metastasis of pancreatic cancer cells. These findings indicated that the HPA/SDC1 axis may be used as an effective therapeutic target for pancreatic cancer.

9.
Cell Cycle ; 18(22): 3206-3222, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31571517

RESUMO

Recently, the impacts of microRNAs (miRNAs) have been identified in epilepsy (EP), this study was designed to assess the role of miR-183 in hippocampal neuron injury in EP. Rat EP models were established by injected with lithium-pilocarpine. The pathological observation of rats' hippocampus sections was conducted. Expression of miR-183, Foxp1, Jak1, Stat1, and Stat3 in rats' hippocampal tissues was determined by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis. The proliferation ability and the apoptosis of the rats' neurons were measured. Furthermore, the target relation between miR-183 and Foxp1 was determined by bioinformatics analysis and dual-luciferase gene reporter assay. The levels of miR-183, Jak1, Stat1, and Stat3 were elevated, and the expression of Foxp1 was declined in EP rats' hippocampal tissues. Inhibited miR-183 could up-regulate Foxp1, inhibited miR-183 together with up-regulated Foxp1 could repress hippocampal neuron injury, promote neuron proliferation, suppress neuron apoptosis, and inactivate the Jak/Stat signaling pathway, resulting in an attenuation of EP progression. Moreover, down-regulated Foxp1 could reverse the attenuation of EP progression which was contributed by inhibited miR-183. Our study implies that inhibited miR-183 could up-regulate Foxp1, resulting in an inactivation of the Jak/Stat signaling pathway and promotion of neuron proliferation, as well as inhibition of apoptosis of hippocampal neurons in EP rats, by which the hippocampal neuron injury and EP progression could be repressed.


Assuntos
Epilepsia/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Hipocampo/metabolismo , Janus Quinase 1/metabolismo , MicroRNAs/metabolismo , Neurônios/metabolismo , Proteínas Repressoras/metabolismo , Animais , Apoptose/genética , Proliferação de Células/genética , Células Cultivadas , Progressão da Doença , Regulação para Baixo , Epilepsia/induzido quimicamente , Epilepsia/genética , Fatores de Transcrição Forkhead/genética , Hipocampo/citologia , Hipocampo/patologia , Hipocampo/ultraestrutura , Janus Quinase 1/genética , Masculino , MicroRNAs/genética , Microscopia Eletrônica de Transmissão , Neurônios/citologia , Neurônios/patologia , Neurônios/ultraestrutura , Ratos , Ratos Sprague-Dawley , Proteínas Repressoras/genética , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/genética
10.
Int J Surg Case Rep ; 61: 218-221, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31377548

RESUMO

INTRODUCTION: Extrahepatic biliary non-Hodgkin's lymphoma (EBNHL) is rare, with a prevalence of 0.6% of malignant biliary tumors. Primary biliary non-Hodgkin's lymphoma accounts for 0.4% of extranodal non-Hodgkin's lymphoma (NHL), accounting for approximately 0.016% of all NHL cases. The patient presented with typical bile duct disappearance syndrome. The late performance is a bloodthirsty syndrome. PRESENTATION OF CASE: This patient was admitted to the hospital with "intermittent fever, abdominal pain for 19 days". The relevant laboratory tests showed severe infection. The patients were treated according to abdominal infection, and then laparoscopic cholecystectomy was performed. After the operation, the patient's condition did not relieve and further deteriorated. Postoperative patient performance was not based on preoperative estimates, and surgery did not achieve the desired results. Postoperative pathological diagnosis confirmed gallbladder non-Hodgkin's lymphoma. The patient eventually died. DISCUSSION: Non-calculus inflammation occurs more frequently in the gallbladder. Non-calculus infections are generally caused by bile stasis and ischemia, resulting in bacterial reproduction and reduced blood supply, and gangrene and perforation of the gallbladder are more likely to occur. This patient is also diagnosed and treated according to this idea. The development after surgery completely exceeded our expectations. Gallbladder non-Hodgkin's lymphoma is very rare, and this case also includes hemophagocytic syndrome and bile duct disappearance syndrome, which is rare. CONCLUSION: Malignant lymphoma of the extrahepatic biliary system is extremely rare, and its clinical manifestations are easily misdiagnosed. At the same time, non-calculous cholecystitis with fever, jaundice and hepatosplenomegaly should be considered.

11.
Heart Lung Circ ; 28(8): 1206-1212, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30166260

RESUMO

BACKGROUND: Although several studies have assessed the effect of Tai Chi in management of chronic obstructive pulmonary disease (COPD), these studies have a wide sample variation and convey inconclusive results. This study aims to determine if a 3-month Tai Chi program improves lung function, exercise capacity, and health related quality of life (HRQoL) in people with COPD. METHODS: A randomised controlled, single blind trial was undertaken. Patients were randomly allocated to either Tai Chi group (n=26) or control group (n=24). Participants in the Tai Chi group received a Tai Chi exercise program three times weekly for 3-months while participants in the control group were advised to maintain their routine activities. Outcome measures included lung function, 6-minute walk distance (6WMD) and COPD Assessment Test (CAT). The measurements took place at baseline and immediately after the 3-month intervention period. RESULTS: Of 50 participants, 46 completed the intervention. Compared to control, Tai Chi significantly increased 6WMD (mean difference 60.5m, 95% CI 30.27-78.69), and reduced score of CAT (mean difference 14 points, 95% CI 11-24). An 86% compliance to the Tai Chi training was noted and no adverse events were observed in Tai Chi group. CONCLUSIONS: The Tai Chi program is a safe, effective and feasible method to improve exercise capacity and health-related quality of life in people with COPD.


Assuntos
Tolerância ao Exercício , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/terapia , Qualidade de Vida , Tai Chi Chuan , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Testes de Função Respiratória
12.
J Mol Recognit ; 28(6): 359-68, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25736423

RESUMO

The novel reductive graphene oxide-based magnetic molecularly imprinted poly(ethylene-co-vinyl alcohol) polymers (rGO@m-MIPs) were successfully synthesized as adsorbents for six kinds of polychlorinated biphenyls (PCBs) in fish samples. rGO@m-MIPs was prepared by surface molecular imprinting technique. Besides, Fe3 O4 nanoparticles (NPs) were employed as magnetic supporters, and rGO@Fe3 O4 was in situ synthesis. Different from functional monomer and cross-linker in traditional molecularly imprinted polymer, here, 3,4-dichlorobenzidine was employed as dummy molecular and poly(ethylene-co-vinyl alcohol) was adopted as the imprinted polymers. After morphology and inner structure of the magnetic adsorbent were characterized, the adsorbent was employed for disperse solid phase extraction toward PCBs and exhibited great selectivity and high adsorption efficiency. This material was verified by determination of PCBs in fish samples combined with gas chromatography-mass spectrometry (GC-MS) method. According to the detection, the low detection limits (LODs) of PCBs were 0.0035-0.0070 µg l(-1) and spiked recoveries ranged between 79.90 and 94.23%. The prepared adsorbent can be renewable for at least 16 times and expected to be a new material for the enrichment and determination of PCBs from contaminated fish samples.


Assuntos
Grafite/química , Carne/análise , Bifenilos Policlorados/isolamento & purificação , Polietilenos/química , Polivinil/química , Adsorção , Animais , Peixes , Contaminação de Alimentos , Cinética , Fenômenos Magnéticos , Impressão Molecular , Oxirredução , Bifenilos Policlorados/química
13.
Proc Natl Acad Sci U S A ; 112(2): E103-9, 2015 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-25548155

RESUMO

Atomic steps, a defect common to all crystal surfaces, can play an important role in many physical and chemical processes. However, attempts to predict surface dynamics under nonequilibrium conditions are usually frustrated by poor knowledge of the atomic processes of surface motion arising from mass transport from/to surface steps. Using low-energy electron microscopy that spatially and temporally resolves oxide film growth during the oxidation of NiAl(100) we demonstrate that surface steps are impermeable to oxide film growth. The advancement of the oxide occurs exclusively on the same terrace and requires the coordinated migration of surface steps. The resulting piling up of surface steps ahead of the oxide growth front progressively impedes the oxide growth. This process is reversed during oxide decomposition. The migration of the substrate steps is found to be a surface-step version of the well-known Hele-Shaw problem, governed by detachment (attachment) of Al atoms at step edges induced by the oxide growth (decomposition). By comparing with the oxidation of NiAl(110) that exhibits unimpeded oxide film growth over substrate steps we suggest that whenever steps are the source of atoms used for oxide growth they limit the oxidation process; when atoms are supplied from the bulk, the oxidation rate is not limited by the motion of surface steps.

14.
J Sep Sci ; 37(13): 1591-600, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24737691

RESUMO

Novel multi-walled carbon nanotube modified dummy-template molecularly imprinted microspheres (MWCNTs@DMMIPs) were successfully synthesized as adsorbents for six kinds of polychlorinated biphenyls (PCBs). MWCNTs@DMMIPs were prepared by a surface molecular imprinting technique. Core-shell Fe3 O4 @SiO2 nanoparticles were employed as magnetic support. 3,4-Dichlorobenzene acetic acid was used as a dummy template instead of PCBs, methacrylic acid was used as functional monomer and ethylene glycol dimethacrylate was used as the cross-linker. The resulting absorbent was characterized by various methods. The adsorbent was employed for extracting PCBs and exhibited good selectivity and high adsorption efficiency. Furthermore, it was reusable and capable of magnetic separation. Adsorption kinetics fit well with a pseudo-second-order kinetic equation and also exhibited a three-stage intra-particle diffusion model. The Freundlich model was used to describe the adsorption isotherms. The materials were successfully applied to the magnetic dispersive solid-phase extraction of six kinds of PCBs followed by gas chromatography with mass spectrometry determination in fish samples, the limit of detection of six kinds of PCBs were 0.0028-0.0068 µg/L and spiked recoveries ranged between 73.41 and 114.21%. The prepared adsorbent was expected to be a new material for the removal and recovery of PCBs from contaminated foods.


Assuntos
Nanotubos de Carbono/química , Bifenilos Policlorados/isolamento & purificação , Alimentos Marinhos/análise , Extração em Fase Sólida/métodos , Adsorção , Animais , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Magnetismo , Microesferas , Impressão Molecular , Perciformes , Bifenilos Policlorados/química , Extração em Fase Sólida/instrumentação
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