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1.
Cancer Sci ; 114(12): 4583-4595, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37752684

RESUMO

Amplification of amino acids synthesis is reported to promote tumorigenesis. The serine/glycine biosynthesis pathway is a reversible conversion of serine and glycine catalyzed by cytoplasmic serine hydroxymethyltransferase (SHMT)1 and mitochondrial SHMT2; however, the role of SHTM1 in renal cell carcinoma (RCC) is still unclear. We found that low SHMT1 expression is correlated with poor survival of RCC patients. The in vitro study showed that overexpression of SHMT1 suppressed RCC proliferation and migration. In the mouse tumor model, SHMT1 significantly retarded RCC tumor growth. Furthermore, by gene network analysis, we found several SHMT1-related genes, among which homeobox D8 (HOXD8) was identified as the SHMT1 regulator. Knockdown of HOXD8 decreased SHMT1 expression, resulting in faster RCC growth, and rescued the SHMT1 overexpression-induced cell migration defects. Additionally, ChIP assay found the binding site of HOXD8 to SHMT1 promoter was at the -456~-254 bp region. Taken together, SHMT1 functions as a tumor suppressor in RCC. The transcription factor HOXD8 can promote SHMT1 expression and suppress RCC cell proliferation and migration, which provides new mechanisms of SHMT1 in RCC tumor growth and might be used as a potential therapeutic target candidate for clinical treatment.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Animais , Humanos , Camundongos , Carcinoma de Células Renais/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Glicina , Glicina Hidroximetiltransferase/genética , Glicina Hidroximetiltransferase/química , Glicina Hidroximetiltransferase/metabolismo , Proteínas de Homeodomínio/genética , Neoplasias Renais/genética , Serina/metabolismo , Fatores de Transcrição
2.
PLoS One ; 17(8): e0272430, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35939494

RESUMO

Municipal amalgamation is one of the core policy tools for Chinese government intervention in urbanization. The city-county merger policy provides a valuable research object for examining whether government-led urban expansion improves the quality of public services. By using city panel data from 2003 to 2019, this paper examines the policy effects of city-county mergers on the quality of public services using the Propensity Score Matching-Difference-in-Differences (PSM-DID) model. The results indicate that, after controlling for other factors, city-county mergers have increased the quality of public services by 1.2%. A placebo test has validated the robustness of this positive effect. Through further tests, the paper finds that the policy has positively affected all three aspects of the quality of public services in China: education, health care, and transport infrastructure, with the greatest impact being on education. Using a case study of a city-county merger in the Fenghua District of Ningbo, this paper depicts the transmission mechanism and argues that the policy affects the quality of public services by providing institutional security (financial and administrative power) and promoting regional integration in the new city area.


Assuntos
Governo , Urbanização , China , Cidades , Atenção à Saúde
3.
PeerJ ; 10: e12747, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35047237

RESUMO

Litter quality and climate have been presumed to be the dominant factors regulating litter decomposition rates on broad spatial scales. However, the role of soil fauna on litter decomposition is poorly understood, despite the fact that it could strongly influence decomposition by fragmentation and subsequent modification of the activities of microorganisms.In this study, we carried out a meta-analysis on the effects of soil fauna on litter decomposition rates in Chinese forests, ranging from boreal to tropical forests, based on data from 20 studies. The effects of climatic factors on decomposition rate were assessed by comparing the contribution of soil fauna to litter decomposition from studies carried out at different latitudes.The degree of influence of the soil fauna was in the order tropical (200%) > subtropical (47%) > temperate forest (28%). Comparing the effect size of soil fauna, it was found that when soil fauna was excluded, the decomposition rate, calculated using Olson's equation, was most affected in tropical forest (-0.77), while the litter decomposition rate both subtropical (-0.36) and temperate forest (-0.19) were also suppressed to varying degrees (P < 0.001). These results highlight that soil fauna could promote litter decomposition to different extents. Using stepwise multiple linear regression, the effect size of the soil fauna was negatively correlated with the cellulose and nitrogen concentrations of the initial litter material. In Chinese forests, litter decomposition rates were reduced, on average, by 65% when soil fauna was excluded. The impact of soil fauna on decomposition was shown to be closely related to climate and litter quality.


Assuntos
Folhas de Planta , Solo , Folhas de Planta/fisiologia , Florestas , Clima , Celulose
4.
BMC Public Health ; 21(1): 2001, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34736445

RESUMO

BACKGROUND: As COVID-19 continues to spread globally, traditional emergency management measures are facing many practical limitations. The application of big data analysis technology provides an opportunity for local governments to conduct the COVID-19 epidemic emergency management more scientifically. The present study, based on emergency management lifecycle theory, includes a comprehensive analysis of the application framework of China's SARS epidemic emergency management lacked the support of big data technology in 2003. In contrast, this study first proposes a more agile and efficient application framework, supported by big data technology, for the COVID-19 epidemic emergency management and then analyses the differences between the two frameworks. METHODS: This study takes Hainan Province, China as its case study by using a file content analysis and semistructured interviews to systematically comprehend the strategy and mechanism of Hainan's application of big data technology in its COVID-19 epidemic emergency management. RESULTS: Hainan Province adopted big data technology during the four stages, i.e., migration, preparedness, response, and recovery, of its COVID-19 epidemic emergency management. Hainan Province developed advanced big data management mechanisms and technologies for practical epidemic emergency management, thereby verifying the feasibility and value of the big data technology application framework we propose. CONCLUSIONS: This study provides empirical evidence for certain aspects of the theory, mechanism, and technology for local governments in different countries and regions to apply, in a precise, agile, and evidence-based manner, big data technology in their formulations of comprehensive COVID-19 epidemic emergency management strategies.


Assuntos
COVID-19 , Epidemias , Big Data , China/epidemiologia , Humanos , Governo Local , SARS-CoV-2 , Tecnologia
5.
JMIR Mhealth Uhealth ; 9(1): e26836, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33460389

RESUMO

BACKGROUND: The COVID-19 epidemic is still spreading globally. Contact tracing is a vital strategy in epidemic emergency management; however, traditional contact tracing faces many limitations in practice. The application of digital technology provides an opportunity for local governments to trace the contacts of individuals with COVID-19 more comprehensively, efficiently, and precisely. OBJECTIVE: Our research aimed to provide new solutions to overcome the limitations of traditional contact tracing by introducing the organizational process, technical process, and main achievements of digital contact tracing in Hainan Province. METHODS: A graph database algorithm, which can efficiently process complex relational networks, was applied in Hainan Province; this algorithm relies on a governmental big data platform to analyze multisource COVID-19 epidemic data and build networks of relationships among high-risk infected individuals, the general population, vehicles, and public places to identify and trace contacts. We summarized the organizational and technical process of digital contact tracing in Hainan Province based on interviews and data analyses. RESULTS: An integrated emergency management command system and a multi-agency coordination mechanism were formed during the emergency management of the COVID-19 epidemic in Hainan Province. The collection, storage, analysis, and application of multisource epidemic data were realized based on the government's big data platform using a centralized model. The graph database algorithm is compatible with this platform and can analyze multisource and heterogeneous big data related to the epidemic. These practices were used to quickly and accurately identify and trace 10,871 contacts among hundreds of thousands of epidemic data records; 378 closest contacts and a number of public places with high risk of infection were identified. A confirmed patient was found after quarantine measures were implemented by all contacts. CONCLUSIONS: During the emergency management of the COVID-19 epidemic, Hainan Province used a graph database algorithm to trace contacts in a centralized model, which can identify infected individuals and high-risk public places more quickly and accurately. This practice can provide support to government agencies to implement precise, agile, and evidence-based emergency management measures and improve the responsiveness of the public health emergency response system. Strengthening data security, improving tracing accuracy, enabling intelligent data collection, and improving data-sharing mechanisms and technologies are directions for optimizing digital contact tracing.


Assuntos
COVID-19/prevenção & controle , Busca de Comunicante/métodos , Tecnologia Digital , Epidemias/prevenção & controle , Algoritmos , Big Data , COVID-19/epidemiologia , China/epidemiologia , Gráficos por Computador , Visualização de Dados , Bases de Dados Factuais , Humanos
6.
Artigo em Inglês | MEDLINE | ID: mdl-33375307

RESUMO

During times of public crises (such as COVID-19), governments must act swiftly to release crisis information effectively and efficiently to the public. This paper provides a general overview of the way that the Wuhan local government use Weibo as a channel to engage with their citizens during the COVID-19 pandemic. Based on the media richness, dialogic loop, and a series of theoretically relevant factors, such as content type, text length, and information source, we try to examine how citizen engage with their local government. By analyzing the data mining samples from Wuhan Release, the official Sina Weibo account of Wuhan's local government, results show that, despite the unstable situation COVID-19 over the crisis, there exist three stages of a crisis on the whole. Combining the behavior of the government and the public, duration from 31 December 2019 to 19 January 2020 could be seen as the development period, then the outbreak period (30 January 2020 to 28 February 2020), and a grace period (29 February 2020 to19 April 2020). Public attention to different types of information changes over time, but curbing rumors has always been a priority. Media richness features partially influent citizen engagement. Text length is significantly positively associated with citizen engagement through government social media. However, posts containing information sources have a negative impact on citizen engagement.


Assuntos
COVID-19 , Disseminação de Informação/métodos , Governo Local , Pandemias , Mídias Sociais , China , Humanos
7.
Risk Anal ; 39(1): 180-194, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-28095595

RESUMO

This article studies a general type of initiating events in critical infrastructures, called spatially localized failures (SLFs), which are defined as the failure of a set of infrastructure components distributed in a spatially localized area due to damage sustained, while other components outside the area do not directly fail. These failures can be regarded as a special type of intentional attack, such as bomb or explosive assault, or a generalized modeling of the impact of localized natural hazards on large-scale systems. This article introduces three SLFs models: node centered SLFs, district-based SLFs, and circle-shaped SLFs, and proposes a SLFs-induced vulnerability analysis method from three aspects: identification of critical locations, comparisons of infrastructure vulnerability to random failures, topologically localized failures and SLFs, and quantification of infrastructure information value. The proposed SLFs-induced vulnerability analysis method is finally applied to the Chinese railway system and can be also easily adapted to analyze other critical infrastructures for valuable protection suggestions.

8.
PLoS One ; 10(6): e0128824, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26057126

RESUMO

Phytoremediation is a promising means of ameliorating heavy metal pollution through the use of transgenic plants as artificial hyperaccumulators. A novel Streptococcus thermophilus γ-glutamylcysteine synthetase-glutathione synthetase (StGCS-GS) that synthesizes glutathione (GSH) with limited feedback inhibition was overexpressed in sugar beet (Beta vulgaris L.), yielding three transgenic lines (s2, s4 and s5) with enhanced tolerance to different concentrations of cadmium, zinc and copper, as indicated by their increased biomass, root length and relative growth compared with wild-type plants. Transgenic sugar beets accumulated more Cd, Zn and Cu ions in shoots than wild-type, as well as higher GSH and phytochelatin (PC) levels under different heavy metal stresses. This enhanced heavy metal tolerance and increased accumulation were likely due to the increased expression of StGCS-GS and consequent overproduction of both GSH and PC. Furthermore, when multiple heavy metal ions were present at the same time, transgenic sugar beets overexpressing StGCS-GS resisted two or three of the metal combinations (50 µM Cd-Zn, Cd-Cu, Zn-Cu and Cd-Zn-Cu), with greater absorption in shoots. Additionally, there was no obvious competition between metals. Overall, the results demonstrate the explicit role of StGCS-GS in enhancing Cd, Zn and Cu tolerance and accumulation in transgenic sugar beet, which may represent a highly promising new tool for phytoremediation.


Assuntos
Proteínas de Bactérias/metabolismo , Beta vulgaris/genética , Resistência a Medicamentos , Metais Pesados/toxicidade , Plantas Geneticamente Modificadas/genética , Proteínas de Bactérias/genética , Beta vulgaris/efeitos dos fármacos , Beta vulgaris/metabolismo , Biotransformação , Metais Pesados/metabolismo , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/metabolismo , Streptococcus thermophilus/genética , Estresse Fisiológico
9.
Ecol Evol ; 4(7): 1039-48, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24772281

RESUMO

Soil physic-chemical properties differ at different depths; however, differences in afforestation-induced temporal changes at different soil depths are seldom reported. By examining 19 parameters, the temporal changes and their interactions with soil depth in a large chronosequence dataset (159 plots; 636 profiles; 2544 samples) of larch plantations were checked by multivariate analysis of covariance (MANCOVA). No linear temporal changes were found in 9 parameters (N, K, N:P, available forms of N, P, K and ratios of N: available N, P: available P and K: available K), while marked linear changes were found in the rest 10 parameters. Four of them showed divergent temporal changes between surface and deep soils. At surface soils, changing rates were 262.1 g·kg(-1)·year(-1) for SOM, 438.9 mg·g(-1)·year(-1) for C:P, 5.3 mg·g(-1)·year(-1) for C:K, and -3.23 mg·cm(-3)·year(-1) for bulk density, while contrary tendencies were found in deeper soils. These divergences resulted in much moderated or no changes in the overall 80-cm soil profile. The other six parameters showed significant temporal changes for overall 0-80-cm soil profile (P: -4.10 mg·kg(-1)·year(-1); pH: -0.0061 unit·year(-1); C:N: 167.1 mg·g(-1)·year(-1); K:P: 371.5 mg·g(-1) year(-1); N:K: -0.242 mg·g(-1)·year(-1); EC: 0.169 µS·cm(-1)·year(-1)), but without significant differences at different soil depths (P > 0.05). Our findings highlight the importance of deep soils in studying physic-chemical changes of soil properties, and the temporal changes occurred in both surface and deep soils should be fully considered for forest management and soil nutrient balance.

10.
Ying Yong Sheng Tai Xue Bao ; 25(9): 2511-20, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25757299

RESUMO

Dendrochronological techniques including correlation functions and single-years analysis were used to study the relationship between the two kinds of Korean pine radial growth in Liangshui Natural Reserve and climatic variables, and to assess the similarities and differences between Korean pine with coarse bark (Pinus koraiensis forma pachidermis) and fine bark (Pinus koraiensis forma leptodermis) in response to climate factors, the main affecting factors and whether the response relationship could be of long-term stability. The results showed that the Korean pine with fine bark was more suitable for dendrochronological study. The radial growth of the two kinds of Korean pine was very sensitive to environmental variables and their climate responses had no significant differ- ences. From 1902 to 2009, meteorological factors in the growing season, especially in June were the primary factors affecting the radial growth of the two kinds of Korean pine in the study area. The temperature showed a significant negative correlation and the precipitation showed a significant positive correlation. The Korean pine growing in different periods had a significantly different iresponse to meteorological factors. With the rapid rise of temperature and drought after 1970, the radial growth of the two kinds of Korean pine was more sensitive to the meteorological factors than before, which was especially more sensitive to temperature in growing season and PDSI in many seasons.


Assuntos
Clima , Pinus/crescimento & desenvolvimento , China , Casca de Planta , Estações do Ano , Temperatura
11.
Curr Microbiol ; 58(2): 129-33, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18946700

RESUMO

A gene encoding the rice (Oryza sativa L.) 90-kDa heat shock protein (OsHsp90) was introduced into Escherichia coli using the pGEX-6p-3 expression vector with a glutathione-S-transferase (GST) tag to analyze the possible function of this protein under heat stress for the first time. We compared the survivability of E. coli (BL21) cells transformed with a recombinant plasmid containing GST-OsHsp90 fusion protein with control E. coli cells transformed with the plasmid containing GST and the wild type BL21 under heat shock after isopropyl beta-D: -thiogalactopyranoside induction. Cells expressing GST-OsHsp90 demonstrated thermotolerance at 42, 50, and 70 degrees C, treatments that were more harmful to cells expressing GST and the wild type. Further studies were carried out to analyze the heat-induced characteristics of OsHsp90 at 42, 50, and 70 degrees C in vitro. When cell lysates from E. coli transformants were heated at these heat stresses, expressed GST-OsHsp90 prevented the denaturation of bacterial proteins treated with 42 degrees C heat shocks, and partially prevented that of proteins treated at 50 and 70 degrees C; meanwhile, cells expressing GST-OsHsp90 withstood the duration at 50 degrees C. These results indicate that OsHsp90 functioned as a chaperone, binding to a subset of substrates, and maintained E. coli growth well at high temperatures.


Assuntos
Escherichia coli/fisiologia , Expressão Gênica , Proteínas de Choque Térmico HSP90/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Escherichia coli/genética , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Resposta ao Choque Térmico , Proteínas de Plantas/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
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