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1.
Syst Rev ; 11(1): 226, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36271453

RESUMO

BACKGROUND: Recently, several systematic reviews (SRs) and meta-analyses (MAs) of Tripterygium wilfordii polyglycoside (TWP) have reported significant benefits on diabetic kidney disease (DKD). However, the adoption of TWP for DKD remains uncommon. This study aimed to evaluate and summarize the current evidence on TWP for DKD. METHODS: We searched PubMed, Web of Science, SINOMED, Embase, Cochrane Library, CNKI database, Wan Fang database, and VIP database, up to June 4, 2022. SRs of TWP on DKD were included. Two authors independently assessed eligibility, extracted data, and graded the quality of evidence. We appraised the reporting and methodological quality of the included studies based on the PRISMA statement and AMSTAR 2. RESULTS: We included 19 SRs and MAs. Seventeen MAs of proteinuria were identified; all suggested TWP exhibited anti-proteinuria function on DKD. Of these, only 2 were graded as moderate quality of evidence. Eighteen MAs estimated the reno-protective effect of TWP; nine of them showed that TWP improved renal function, including 2 MAs rated as moderate quality of evidence. Eleven SRs showed the serum albumin level was elevated in the TWP group. Of those, four were rated as moderate quality of evidence. Fourteen MAs of the incidence of adverse events were included. Twelve MAs indicated TWP increased the risk of adverse events, of which 4 were graded with moderate quality of evidence. Twenty of the 27 items in the PRISMA checklist were adequately reported with more than 75% compliance among the included SRs, while five of the 12 items in the PRISMA checklist for abstract were found to have less than 50% compliance. The overall reporting quality of SRs published in English was higher than that in Chinese. The methodological quality of the included SRs appraised by AMSTAR-2 ranged from critically low to moderate. CONCLUSION: TWP appears effective for DKD on improving proteinuria and increasing the level of serum albumin, accompanied by a higher risk of adverse events. The evidence would be more credible and valuable to guide decision if the quality of the SRs and primary studies is improved. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42021249560.


Assuntos
Nefropatias Diabéticas , Tripterygium , Humanos , Nefropatias Diabéticas/tratamento farmacológico , Tripterygium/efeitos adversos , Revisões Sistemáticas como Assunto , Metanálise como Assunto
2.
Int Heart J ; 62(2): 371-380, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33731513

RESUMO

Coronary artery disease (CAD) is one of the heavy health burdens worldwide. Aberrant proliferation of vascular smooth muscle cells (VSMCs) contributes to the occurrence and development of CAD. This study aimed at exploring differentially expressed microRNAs (miRNAs) and their regulatory mechanisms in the development of CAD.The miRNA expression profile of GSE28858 was obtained from the Gene Expression Omnibus database. Differentially expressed miRNAs (DEmiRNAs) between CAD and healthy control samples were analyzed using limma package in R. Target genes of DEmiRNAs were predicted, and a miRNA-target gene network was constructed. The relationship between miR-665 and transforming growth factor beta receptor 1 (TGFBR1) was selected for further analysis. The interaction between miR-665 and TGFBR1 was confirmed by dual luciferase reporter assay. Effects of miR-665 on cell viability and apoptosis of VSMCs were evaluated by cell counting kit-8 (CCK-8) assay and flow cytometry, respectively. Besides, western blot assays for BCL2L11 and caspase 3 were also conducted.A total of 38 upregulated miRNAs and 28 downregulated miRNAs were identified. The expression level of miR-665 was significantly downregulated in patients with CAD. TGFBR1 was proved to be a target gene of miR-665. Besides, ectopic expression of miR-665 obviously inhibited VSMC growth and promoted VSMC apoptosis. TGFBR1 overexpression in VSMCs transfected with miR-665 mimic could restore the effect of miR-665 on the proliferation and apoptosis of VSMCs.MiR-665 might participate in the proliferation and apoptosis of VSMCs by targeting TGFBR1.


Assuntos
Doença da Artéria Coronariana/genética , Regulação da Expressão Gênica , MicroRNAs/genética , Miócitos de Músculo Liso/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Apoptose , Movimento Celular , Proliferação de Células , Células Cultivadas , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Regulação para Baixo , Feminino , Humanos , Masculino , MicroRNAs/biossíntese , Miócitos de Músculo Liso/patologia , Receptor do Fator de Crescimento Transformador beta Tipo I/biossíntese , Regulação para Cima
4.
Comput Math Methods Med ; 2020: 8183420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695216

RESUMO

BACKGROUND: Coronary artery disease (CAD) is a type of heart disease with a high morbidity rate. This study is aimed at identifying potential biomarkers closely related to the progression of CAD. MATERIALS AND METHODS: A microarray dataset of GSE59867 was downloaded from a public database, Gene Expression Omnibus, which included 46 cases of stable CAD without a history of myocardial infarction (MI), 30 cases of MI without heart failure (HF), and 34 cases of MI with HF. Differentially expressed long noncoding RNAs (DElncRNAs) and mRNAs (DEmRNAs) were identified by the limma package, and functions of DEmRNAs were annotated by Gene Ontology and KEGG pathways. In addition, weighed gene coexpression network analysis (WGCNA) was used to construct a coexpression network of DEmRNAs, and a disease-related lncRNAs-mRNAs-pathway network was constructed. Finally, the datasets of GSE61145 and GSE57338 were used to verify the expression levels of the above highly correlated candidates. RESULTS: A total of 2362 upregulated mRNAs and 2816 downregulated mRNAs, as well as 235 upregulated lncRNAs and 113 downregulated lncRNAs were screened. These genes were significantly enriched in "cytokine-cytokine receptor interaction," "RIG-I-like receptor signaling pathway," and "natural killer cell-mediated cytotoxicity." Five modules including 1201 DEmRNAs were enriched in WGCNA. A coexpression network including 19 DElncRNAs and 413 DEmRNAs was constructed. These genes were significantly enriched in "phosphatidylinositol signaling system," "insulin signaling pathway," and "MAPK signaling pathway". Disease-related gene-pathway network suggested FASN in "insulin signaling pathway," DGKZ in "phosphatidylinositol signaling system," and TNFRSF1A in "MAPK signaling pathway" were involved in MI. CONCLUSION: FASN, DGKZ, and TNFRSF1A were revealed to be CAD progression-associated genes by WGCNA coexpression network analysis.


Assuntos
Doença da Artéria Coronariana/genética , Redes Reguladoras de Genes , RNA Longo não Codificante/genética , Biologia Computacional , Doença da Artéria Coronariana/etiologia , Bases de Dados Genéticas , Progressão da Doença , Ontologia Genética , Estudos de Associação Genética , Marcadores Genéticos , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/genética , Humanos , Conceitos Matemáticos , Modelos Cardiovasculares , Modelos Genéticos , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/genética , RNA Mensageiro/genética , Transdução de Sinais/genética
5.
Environ Pollut ; 192: 44-51, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24880535

RESUMO

Studies have been devoted to the transport and accumulation of persistent organic pollutants (POPs) in mountain environments. The Himalayas have the widest altitude gradient of any mountain range, but few studies examining the environmental behavior of POPs have been performed in the Himalayas. In this study, air, soil, and leaf samples were collected along a transect on the southern slope of the Himalayas, Nepal (altitude: 135-5100 m). Local emission occurred in the lowlands, and POPs were transported by uplift along the slope. During the atmospheric transport, the HCB proportion increased from the lowlands (20%) to high elevation (>50%), whereas the proportions of DDTs decreased. The largest residue of soil POPs appeared at an altitude of approximately 2500 m, and may be related to absorption by vegetation and precipitation. The net deposition tendencies at the air-soil surface indicated that the Himalayas may be a 'sink' for DDTs and PCBs.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Ar , Altitude , Atmosfera/química , Substâncias Perigosas/análise , Nepal , Folhas de Planta/química , Bifenilos Policlorados/análise , Solo/química , Poluentes do Solo/análise
6.
Environ Pollut ; 188: 94-101, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24568793

RESUMO

Remote forests are considered a pool of Mercury (Hg) in the global Hg cycle. However, notably few studies have investigated the fate of Hg in the Tibetan forest. In this study, fifty-two foliage samples and seven litter/soil profiles were collected throughout the Tibetan forest. The concentrations of total Hg (THg) in foliage were positively correlated with longitude and negatively correlated with altitude, indicating that the emission of Hg is expected to decrease with increasing distance from emission sources to the Tibetan forest. The deposition flux of THg in the Tibetan forest (with an air-to-forest ground flux of 9.2 µg/m(2)/year) is ∼2 times the flux in clearings, which is suggestive of enhanced Hg deposition by the forest. The depositional Hg is eventually stored in the forest soil, and the soil acts as a net 'sink' for Hg.


Assuntos
Fenômenos Ecológicos e Ambientais , Mercúrio/análise , Poluentes do Solo/análise , Solo/química , Altitude , Meio Ambiente , Tibet , Árvores/química
7.
Environ Pollut ; 170: 145-51, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22796648

RESUMO

There are limited data on persistent organic pollutants (POPs) in the soils of the Tibetan Plateau. This paper presents data from a survey of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in 40 background surface (0-5 cm) soils of the Tibetan Plateau. Soil concentrations (pg/g, dw) ranged as follows: DDTs, 13-7700; HCHs, 64-847; HCB, 24-564; sum of 15 PCBs, 75-1021; and sum of 9 PBDEs, below detection limit -27. Soil DDT, HCB, PCB and PBDE concentrations were strongly influenced by soil organic carbon content. HCH concentrations were clearly associated with the proximity to source regions in south Asia. The air-soil equilibrium status of POPs suggested the Tibetan soils may be partial "secondary sources" of HCB, low molecular weight PCBs and HCHs and will likely continue to be "sinks" for the less volatile DDE and DDT.


Assuntos
Poluentes Atmosféricos/análise , Fenômenos Ecológicos e Ambientais , Monitoramento Ambiental , Poluentes do Solo/análise , Éteres Difenil Halogenados/análise , Hexaclorobenzeno , Praguicidas/análise , Bifenilos Policlorados/análise , Solo/química , Tibet
8.
Environ Sci Technol ; 44(8): 2988-93, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20235613

RESUMO

So far there are limited data on persistent organic pollutants (POPs) in the atmosphere of the Tibetan Plateau. XAD 2-resin based passive air samplers were therefore deployed for 1 year (between July 2007-June 2008) at 16 locations across the Tibetan Plateau. Based on previously reported sampling rates (R) derived in the north and south America, and their correlations with atmospheric temperature and pressure, R values in the present study were in the range of 2.2-3.3 m(3) d(-1) (average = 2.7 +/- 0.3). Derived air concentrations (pg/m(3)) ranged as follows: DDTs, 5-75; HCHs, 0.1-36; alpha-endosulfan, 0.1-10; HCB, 2.8-80; sum of 15 PCBs, 1.8-8.2; and sum of 9 PBDEs, 0.1-8.3. The highest DDTs occurred at Qamdo, where the sampling site is near to farm land, indicating the spatial distribution of DDTs across the plateau may be influenced by scattered local usage of DDT. Higher levels of HCHs were observed at sites with high elevation (>4000 m) and close to the China-India border, indicating possible long-range atmospheric transport. The highest levels of HCB, PCBs, and PBDEs were found at a site impacted by forest fire during the sampling campaign.


Assuntos
Poluentes Atmosféricos/análise , Éteres Difenil Halogenados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Tibet
9.
FEMS Microbiol Ecol ; 70(2): 9-20, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19796140

RESUMO

Glaciers accumulate airborne microorganisms year by year and thus are good archives of microbial communities and their relationship to climatic and environmental changes. Hypotheses have focused on two possible drivers of microbial community composition in glacier systems. One is aeolian deposition, in which the microbial load by aerosol, dust, and precipitation events directly determines the amount and composition of microbial species in glacier ice. The other is postdepositional selection, in which the metabolic activity in surface snow causes microbial community shifts in glacier ice. An additional possibility is that both processes occur simultaneously. Aeolian deposition initially establishes a microbial community in the ice, whereas postdeposition selection strengthens the deposition patterns of microorganisms with the development of tolerant species in surface snow, resulting in varying structures of microbial communities with depth. In this minireview, we examine these postulations through an analysis of physical-chemical and biological parameters from the Malan and Vostok ice cores, and the Kuytun 51 Glacial surface and deep snow. We discuss these and other recent results in the context of the hypothesized mechanisms driving microbial community succession in glaciers. We explore our current gaps in knowledge and point out future directions for research on microorganisms in glacial ecosystems.


Assuntos
Ecossistema , Microbiologia Ambiental , Camada de Gelo , Cianobactérias/classificação , Cianobactérias/isolamento & purificação , DNA Bacteriano/genética , Monitoramento Ambiental , Eucariotos/classificação , Eucariotos/isolamento & purificação , Filogenia , RNA Ribossômico 16S/genética
10.
Huan Jing Ke Xue ; 29(6): 1488-94, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18763489

RESUMO

During August and September, 2006, a total of 50 samples had been collected from three different snowpits at the Yamzhog Yumco Basion in the south of the Tibetan Plateau. All samples were analyzed for major cations (Na+, NH4+, K+, Ca2+ and Mg2+), anions (Cl-, SO4(2-) and NO3-) and stable oxygen isotope ratio. The results of analyses show that the three snowpits represent accordant chemical characteristics, with NO3- (16.1-187.2 microg x L(-1), averaging at 93.7 microg x L(-1)) and Ca2+ (19.0-236.7 microg x L(-1), averaging at 81.0 microg x L(-1)) being the highest concentration of anions and cations respectively. Compared with data from other representative sites, major ion concentrations in the Yamzhog Yumco Basion accord with those in the south of the plateau, but they differ much from those in the north of th eplateau. Remarkable variabilities of major ion concentrations from monsoon period to non-monsoon period are demonstrated. Ion concentrations of NO3-, NH4+ increase 30%-40% in monsoon period due to the influences of vegetation, live-stock, anthropogenic activity and thunderstorm, whilst the concentrations of crustal source ions, such as Ca2+, Mg2+ reduce 80% due to decrease of dust and strong wind from the north of the plateau and crustal aerosols being washed out of the atmosphere by heavy precipitation during the monsoon period. Variation of ion concentrations are also impacted by elevation and post-deposition process, with Ca2+, Mg2+ increasing with a decrease in elevation and SO4(2-), NO3- decrease with an increase in elevation and the influence of post-deposition.


Assuntos
Poluentes Atmosféricos/análise , Ânions/análise , Cátions/análise , Neve , Monitoramento Ambiental/métodos , Geografia , Solo/análise , Tibet
11.
Huan Jing Ke Xue ; 29(2): 273-82, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18613491

RESUMO

Recently, atmospheric distribution, transport, and reaction of persistent organic pollutants (POPs) in remote areas are getting more attention. Based on the passive air sampler, the networks are established for studying the temporal and spatial distribution of atmospheric POPs in remote areas. The results suggest that the atmospheric concentrations of POPs display a peak value in the 1980s. As the use of POPs has been forbidden after 1980s, concentrations of POPs in air are generally reduced. Concentration of POPs in atmosphere is influenced by temperature and seasonal usage. High concentration of organochlorine pesticides is observed in summer and the comparatively low level is detected in winter. For PAHs, the trend is contrary. High volatility and long-range transport of POPs lead to the global distribution of POPs and accumulation of POPs in remote areas. High mountain is the "acceptor" of atmospheric POPs and cold condensation plays the main role in capturing POPs in high elevation areas. Distribution, transport, exchange direction and exchange flux of POPs among air/water, air/soil, air/snow and air/vegetation interfaces are mainly controlled by temperature, precipitation and characteristics of POPs. Models were developed on the basis of the effect of these factors. Taken together the transport model and source analysis of POPs, transport mechanism of POPs seems to be clearer. This paper reviewed the progress about the above-mentioned scientific topics and discussed the deficiencies of current researches. Furthermore, it pointed out the further work needed for the study of atmospheric POPs in remote areas.


Assuntos
Poluentes Atmosféricos/análise , Atmosfera/análise , Monitoramento Ambiental , Compostos Orgânicos/análise , China
12.
Sci Total Environ ; 394(1): 134-43, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18291445

RESUMO

High mountains may serve as condensers for persistent organic pollutants (POPs) and the ice/snow core can provide long-term records of atmospheric deposition of pollutants. In this study, organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) in firn core from Dasuopu Glacier were analyzed and the seasonal variation and deposition flux of these pollutants were investigated. PCB 28 was always detected in samples from different firn core layers and concentrations of PCB 28 were in the range of 0.09-0.3 ng/l. Hexachlorobenzene (HCB) and total DDTs (p-p'-DDD and p-p'-DDT) were not always detected and were only present in some samples. No p-p'-DDE and hexachlorocyclohexane (HCH) were detected above the level of determination limits. Concentrations of HCB ranged from 0.04 to 0.07 ng/l, and total DDTs were in the range of 0.15-0.3 ng/l. Total glacier PAHs was below 26 ng/l. The levels of OCPs and PAHs in Dasuopu glacier were roughly similar to values from the European mountain areas but lower than those from Lys glacier (Italy) and glacier from Rocky Mountain. Hg concentration (2-35 ng/l) in firn core samples was higher than that of remote region of Arctic. PCB 28 didn't show obvious variation in different seasons, however for major PAH compounds higher values were observed in summer than in winter. With regard to Hg, it displayed winter maximum. Deposition flux of OCPs, PAHs and mercury showed similar results with maximum flux occurring in the 2000s. After 2000/2001, deposition flux decreased and reflected the possible decrease of emissions of these atmospheric pollutants in the adjacent region.


Assuntos
Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Camada de Gelo , Mercúrio/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental
13.
Sci Total Environ ; 372(1): 193-202, 2006 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17055554

RESUMO

High mountains may serve as condenser for persistent organic pollutants (POPs) and the vegetation in remote areas has been used as a means to characterized atmospheric concentrations of air pollutants. In this study, organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) in Himalayan spruce needle samples from Zhangmu-Nyalam region (central-Himalayas) were analyzed and the altitudinal gradient of these pollutants was investigated. Total HCHs and DDTs concentration in needles were in the range of 1.3-2.9 ng g(-1) dry weight and 1.7-11 ng g(-1) dry weight, which were lower than concentrations reported in spruce needles from Alps, however higher than concentrations in conifer needles from mountain areas of Alberta. Total Himalayan spruce needle PAHs was below 600 ng g(-1) and fluorene, phenanthrene and acenaphthene were abundant individual compounds measured. The ratios of alpha-HCH/gamma-HCH in pine needles were similar with the usual values for technical HCH, implying technical HCHs might be used in this region. The high ratios of o-p'-DDT/p-p'-DDT and no p-p'-DDE measured in this study led to the suspicion that a new source of o-p'-DDT and/or p-p'-DDT existed in this region. In addition, higher ratios of low molecular weight-/high molecular weight-PAHs in this region indicated that petroleum combustion, vehicle emission and low-temperature combustion might be the major contributions of PAH source. To examine the POPs distillation, the analyte concentrations were correlated with altitude. The more volatile OCPs, alpha-HCH, gamma-HCH, aldrin and alpha-endosulfan positively correlated with altitude, however, less volatile OCPs (DDT and DDD) inversely related with elevation. Almost all PAHs detected in this area showed positive correlations with altitude. It is worthy to note that heavy PAHs (Benzo[k] fluoranthene and Benzo[a]anthracene) displayed positive correlation, which implied the sources of PAHs were near the sampling sites. The distillation of POPs was strongly affected by the proximity between sampling sites and contaminant sources. If the contaminant sources are close to the mountains, it may be the dominant factor that controls the concentration gradient.


Assuntos
Poluentes Atmosféricos/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Picea/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Altitude , China , Monitoramento Ambiental , Folhas de Planta/química
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