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1.
Materials (Basel) ; 13(6)2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32245076

RESUMO

The differences in microstructural characteristics, mechanical properties, and corrosion behavior of the as-cast and solution-treated Mg-xGd-1.5Nd-0.5Zn-0.5Zr alloys (Mg-xGd, x = 1, 3, and 5) were studied and discussed. The as-cast Mg-xGd alloys mainly consisted of an α-Mg and island-like eutectic (Mg,Zn)3RE phase, a few cuboidal phases (REH2), and a ZnZr phase. With the increase of Gd content, the grain sizes of the as-cast Mg-xGd alloys decreased. Compared to the microstructure of the as-cast Mg-xGd alloys, the eutectic (Mg,Zn)3RE phase disappeared and the cuboidal REH2 phases existed in the solution-treated Mg-xGd alloys. A large amount of ZnZrx phase was precipitated from α-Mg in the Mg-3Gd alloy and demonstrates a flower-like distribution. The ultimate tensile strength (UTS) and yield strength (YS) of the solution-treated Mg-xGd alloys increased with an increasing Gd content, with the UTS and YS of the Mg-5Gd alloys reaching 217.5 and 125.2 MPa, respectively. Immersion and electrochemical tests showed that the as-cast Mg-3Gd alloy presented the best corrosion resistance with a corrosion rate of 0.285 mm/yr. The corrosion resistance of the solution-treated Mg-3Gd alloy attained the lowest value (0.973 mm/yr), due to the large quantities of ZnZrx with a flower-like phase distribution, forming series of galvanic couple groups with the α-Mg.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32049774

RESUMO

BACKGROUND: A prior randomized control trial showed financial incentives increase HIV testing rates for children of unknown HIV status. Translating evidence-based interventions such as these to scale requires an implementation science approach. METHODS: A qualitative study evaluating healthcare providers' perceptions of barriers and facilitators of a previously completed financial incentives intervention for pediatric HIV testing was conducted at healthcare facilities in Kisumu, Kenya. Six focus group discussions with 52 providers explored determinants of acceptability, feasibility and sustainability of financial incentive scale-up for pediatric HIV testing using the Consolidated Framework for Implementation Research to inform question guides and thematic analysis. RESULTS: Providers found the use of financial incentive interventions for pediatric HIV testing to be highly acceptable. First, providers believed financial incentives had a relative advantage over existing strategies because they overcame cost barriers and provided additional motivation to test; however, concerns about how financial incentives would be implemented influenced perceptions of feasibility and sustainability. Secondly, providers expressed concern that already overburdened staff and high costs of financial incentive programs would limit sustainability. Thirdly, providers feared that financial incentives might negatively affect further care due to expectations of repeated financial support and program manipulation. CONCLUSION: Providers viewed financial incentives as an acceptable intervention to scale programmatically to increase uptake of pediatric testing. To ensure feasibility and sustainability of financial incentives in pediatric HIV testing programs, it will be important to clearly define target populations, manage expectations of continued financial support, and establish systems to track testing.

3.
Water Res ; 173: 115584, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32062224

RESUMO

The cause of phytoplankton blooms has been extensively discussed and largely attributed to favorable external conditions such as nitrogen/phosphorus resources, pH and temperature. Here from the standpoint of hormesis response, we propose that phytoplankton blooms are initiated by stimulatory effects of low concentrations of herbicides as environmental contaminants spread over estuaries and lakes. The experimental results revealed general stimulations by herbicides on Microcystis aeruginosa and Selenastrum capricornutum, with the maximum stimulation in the 30-60% range, depending on the agent and experiment. In parallel with enhancing stimulation, the ratio of HP (high-potential) form to LP (low-potential) form of cytochrome b559 (RHL) was observed decreasing, while intracellular reactive oxygen species (ROS) were observed increasing. We propose that the ROS originated from the thermodynamic transformation of cytochrome b559, enhancing the stimulatory response. Furthermore, the results also proved that thermodynamic states of cytochrome b559 could be modulated by nitric oxide, thus affecting cellular equilibrium of oxidative stress (OS) and correspondingly causing the inhibitory effect of higher concentrations of herbicides on phytoplankton. This suggests that hormesis substantially derives from equilibrium shifting of OS. Moreover, it is reasonable to infer that phytoplankton blooms would be motivated by herbicides or other environmental pollutants. This study provides a new thought into global phytoplankton blooms from a contaminant perspective.

4.
Hypertension ; 75(3): 869-876, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31983306

RESUMO

Activated T lymphocytes that infiltrate blood pressure control organs make a critical contribution to the pathogenesis of hypertension. Dendritic cells act as potent antigen-presenting cells to stimulate prohypertensive T cells. However, the mechanisms that facilitate the recruitment of prohypertensive T cells and dendritic cells into the kidney's draining lymph node during hypertension require elucidation. As CCR7 (C-C motif chemokine receptor type 7) directs the homing of lymphocytes and dendritic cells into lymph nodes, we posited that dendritic cell-mediated T lymphocyte stimulation in the renal lymph node is CCR7 dependent and required for a full hypertensive response. We found that CCR7-deficient (CCR7 KO) mice had a blunted hypertensive response in our model of chronic Ang II (angiotensin II) infusion. Ang II-infused CCR7 KO animals had exaggerated accumulation of CD8+ T cells in the kidney but reduced numbers of CD4+ and CD8+ T cells in the kidney's draining lymph node. To understand whether CCR7-dependent homing of T lymphocytes or dendritic cells into the lymph node regulates the hypertensive response, we injected CCR7 KO or wild-type T cells or dendritic cells into CCR7 KO recipients, neither of which restored the full hypertensive response to Ang II infusion. However, adoptive transfer of wild-type but not CCR7 KO T lymphocytes into RAG1 (recombination-activating gene 1)-deficient mice that lack a lymphocyte niche restored full blood pressure elevation during Ang II infusion. Thus, CCR7-dependent interactions between T lymphocytes and dendritic cells are essential for T lymphocyte stimulation and hypertension accruing from inappropriate activation of the renin-angiotensin system.

5.
Aesthetic Plast Surg ; 44(2): 373-378, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31897628

RESUMO

BACKGROUND: There is an anecdotal belief among some surgeons performing Asian eyelid surgery that double eyelid surgery itself decreases eyebrow position. However, the exact amount of descent and the specific changes in the proportion of facial aesthetics are unknown. PURPOSE: The goal of this study is to determine whether there indeed is a change in brow position after double eyelidplasty and to quantify the proportional differences associated with the change. The three-point double eyelids surgery method was used so that the change in the brow position is solely attributed to the surgery itself and not to the excision of redundant skin. METHODS: From January 2016 to December 2017, double eyelid surgery using the three-point technique was performed on 204 patients who did not require skin excision. Their pre- and postoperative photographs were standardized and analyzed. The ratio of the length between the upper edge of the eyebrow and the edge of the lower eyelid (A) and the length between the edge of the lower eyelid and the nasal base (B) as well as the subsequent change in the midfacial proportion was measured and analyzed. RESULTS: There was a statistically significant brow descent after double eyelidplasty. The average preoperative A/B was 0.71 and the average postoperative A/B was 0.67 (P < 0.001). Although the eyebrow distance did not change in 32.5% of patients, the remaining cohort showed average brow descent of 5.6%. And in this cohort that showed descent, linear regression showed that there was a correlation between the ratio of pre- and postoperative eyebrow distance CONCLUSION: Double eyelid surgery can lower the eyebrow in patients with foldless eyelids. This is in accordance with clinical observation in Asian blepharoplasty. In addition, there are associated changes in the proportion of midfacial aesthetics after the surgery. Such knowledge can be helpful in preoperative consulting with patients as well as in predicting postoperative results. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

6.
J Hazard Mater ; 385: 121578, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31732343

RESUMO

During the bloom seasons, the dissolved inorganic nitrogen declines, which results in the occurrence of nitrogen limitation. It is unclear where the nitrogen goes. Our enclosure experiments and batch tests suggested that Microcystis blooms could significantly reduce the nitrogen in water bodies and the key mechanisms for the nitrogen reduction in different layers were different. The assimilation was the main pathway for nitrogen reduction in the surface layer, while denitrification played an important role both at the sediment-water interface and in the overlying water. Stable nitrogen isotope experiments showed that the nitrate reduction efficiency at sediment-water interface was enhanced by Microcystis, reaching to 76.5∼84.7 %. Dissimilation accounted for 63.8∼67.3 % of the nitrate reduction, and the denitrification rate was 7.4∼8.5 times of DNRA rate. In the water column, the Microcystis bloom facilitated the formation of dark/anoxic condition, which favored the denitrification. The Microcystis aggregates collected from the field showed a great potential in removing nitrogen, and the TN in the overly water was reduced by 3.76∼6.03 mg L-1 within two days. This study provided field evidences and deeper insights into the relationship between Microcystis blooms and nitrogen reduction in the whole water column and gave more details about the enhancing effects of Microcystis on nitrogen reduction.

7.
Int J Mol Sci ; 20(20)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614621

RESUMO

Cells of Microcystis are associated with heterotrophic bacteria and organized in colonies in natural environment, which are basic elements in the mass occurrence of cyanobacterial species. Analyzing these colonies by using metagenomics is helpful to understand species composition and relationship. Meanwhile, the difference in population abundance among Microcystis colonies could be used to recover genome bins from metagenome assemblies. Herein, we designed a pipeline to obtain high-quality genomes of mutualistic bacteria from single natural Microcystis colonies. Single colonies were lysed, and then amplified by using multiple displacement amplification to overcome the DNA quantity limit. A two-step assembly was performed after sequencing and scaffolds were grouped into putative bins based on their differential-coverage among species. We analyzed six natural colonies of three prevailing Microcystis species from Lake Taihu. Clustering results proved that colonies of the same species were similar in the microbial community composition. Eight putative population genome bins with wide bacterial diversity and different GC content were identified based on coverage difference among colonies. At the phylum level, proteobacteria was the most abundant besides cyanobacteria. Six of the population bins were further refined into nearly complete genomes (completeness > 90%).


Assuntos
Metagenômica/métodos , Microcystis/classificação , Sequenciamento Completo do Genoma/métodos , Composição de Bases , Genoma Bacteriano , Sequenciamento de Nucleotídeos em Larga Escala , Microcystis/genética , Filogenia , Simbiose
8.
Accid Anal Prev ; 132: 105256, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31442922

RESUMO

This study analyzed the potentially dangerous driving behaviors of commercial truck drivers from both macro and micro perspectives. The analysis was based on digital tachograph data collected over an 11-month period and comprising 4373 trips made by 70 truck drivers. First, different types of truck drivers were identified using principal component analysis (PCA) and a density-based spatial clustering of applications with noise (DBSCAN) at the macro level. Then, a multilevel model was built to extract the variation properties of speeding behavior at the micro level. Results showed that 40% of the truck drivers tended to drive in a substantially dangerous way and the explained variance proportion of potentially extremely dangerous truck drivers (79.76%) was distinctly higher than that of other types of truck drivers (14.70%˜34.17%). This paper presents a systematic approach to extracting and examining information from a big data source of digital tachograph data. The derived findings make valuable contributions to the development of safety education programs, regulations, and proactive road safety countermeasures and management.


Assuntos
Condução de Veículo/psicologia , Comportamento Perigoso , Adulto , Condução de Veículo/estatística & dados numéricos , Big Data , Humanos , Masculino , Pessoa de Meia-Idade , Veículos Automotores/estatística & dados numéricos , Análise Multinível , Ocupações/estatística & dados numéricos , Análise Espaço-Temporal
9.
Sci Rep ; 9(1): 11035, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31363136

RESUMO

Leakage errors damage a qubit by coupling it to other levels. Over the years, several theoretical approaches to dealing with such errors have been developed based on perturbation arguments. Here we propose a different strategy: we use a sequence of finite rotation gates to exactly eliminate leakage errors. The strategy is illustrated by the recently proposed charge quadrupole qubit in a triple quantum dot, where there are two logical states to encode the qubit and one leakage state. We found an su(2) subalgebra in the three-level system, and by using the subalgebra we show that ideal Pauli x and z rotations, which are universal for single-qubit gates, can be generated by two or three propagators. In addition, the magnitude of detuning fluctuation can be estimated based on the exact solution.

10.
BMC Cardiovasc Disord ; 19(1): 160, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31269899

RESUMO

BACKGROUND: Contrast-induced nephropathy (CIN) is one of major and serious complications in patients undergoing percutaneous coronary intervention (PCI). It is unknown whether increased urinary adiponectin (UAPN), a sensitive marker for early renal function impairment, is associated with an increased risk of CIN. Therefore, we prospectively investigate the association of UAPN with CIN. METHODS: We prospectively enrolled 208 patients who were undergoing elective PCI. The baseline UAPN was assessed prior to PCI. The ROC analysis was used to evaluate the predictive value of UAPN for CIN. Multivariate logistic regression analysis was performed to analyze the independent risk factors for CIN. RESULTS: Of 208 patients, CIN occurred in 19 patients (9.13%), and 6 of them (2.88%) required dialysis. Patients with CIN had a higher UAPN level than those without CIN (17.15 ± 12.36 vs. 10.29 ± 3.04 ng/ml, P < 0.01). ROC analysis showed that the optimal cutoff value of UAPN for predicting CIN was 12.24 ng/ml with 68.42% sensitivity and 76.72% specificity (AUC = 0.7204; 95% CI, 0.582-0.859; 푃< 0.01). Multivariate analysis demonstrated that UAPN (OR, 5.071; 95% CI,1.711-15.028; P < 0.01) and serum creatinine (Scr) > 124 µmol/L (OR, 4.210; 95% CI, 1.297-13.669; P < 0.01) were independently associated with CIN. CONCLUSIONS: Our present study showed that a higher baseline UAPN (≥12.24 ng/ml) level was significantly associated with an increased risk for developing CIN post PCI.

11.
Sci Total Environ ; 688: 867-879, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31255824

RESUMO

Freshwater lakes are threatened by harmful blooms characterized by Cyanobacterial Aggregates (CAs) that are normally aggregated with extracellular polysaccharides released by cyanobacteria to form a phycosphere. It is possible that mutualistic relationships exist between bacteria and cyanobacteria in these CAs wherein bacterial products supplement cyanobacterial growth, and cyanobacterial exudates, in turn, serve as substrates for bacteria, thus augmenting the stability of each constituent. However, little is known about the exact interaction between cyanobacteria and their attached bacteria in CAs. Therefore, in this study, we collected 26 CA samples from Lake Taihu, a large freshwater lake in China from March of 2015 to February of 2016. We then sequenced both the V4 regions of 16S rRNA genes and full metagenomes, resulting in 610 Mb of 16S rRNA gene data and 198.98 Gb of high-quality metagenomic data. We observed that two cyanobacteria genera (Microcystis and Dolichospermum) alternately dominated CAs along the sampling time and specific bacterial genera attached to different cyanobacteria genera dominated CAs. More specifically, Dolichospermum dominates CAs when water temperature is low and total nitrogen is high, while Microcystis dominates CAs when water temperature is high and total nitrogen is low. Moreover, we found specific bacterial genera attached to different cyanobacteria genera dominated CAs. The cyanobacteria-bacteria related pairs Dolichospermum-Burkholderia and Microcystis-Hyphomonas were detected by ecological networks construction. Bacterial communities in CAs were found to be more correlated with the cyanobacterial community (Mantel's r = 0.76, P = 0.001) than with environmental factors (Mantel's r = 0.27, P = 0.017). A potential codependent nitrogen-cycling pathway between cyanobacteria and their attached bacteria was constructed, indicating their functional link. Overall, these results demonstrated that mutualistic relationships do, indeed, exist between cyanobacteria and bacteria in CAs at both taxonomic and gene levels, providing biological clues potentially leading to the control of blooms by interventional strategies to disrupt bacteria-cyanobacteria relationships and co-pathways.


Assuntos
Cianobactérias/fisiologia , China , Monitoramento Ambiental , Lagos , Nitrogênio , RNA Ribossômico 16S , Estações do Ano
12.
Sci Total Environ ; 679: 136-147, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31082588

RESUMO

Elucidation of the linkages between the bacterial community composition and chromophoric dissolved organic matter (CDOM) in lake ecosystems is critical for the understanding of the inland water carbon cycling. Despite substantial research into the relationship between the bacteria community and the bulk DOM pool, knowledge of the specific relationship between the optical dynamics of DOM and the bacterioplankton community in lake ecosystems is still poor. We investigated the linkages between the optical dynamics of DOM and bacteria composition in shallow eutrophic Lake Taihu, China. Redundancy Analysis (RDA) indicated that besides water temperature and phytoplankton biomass, also CDOM was an important factor determining the composition of the bacterial community. Generalized Additive Models (GAM) showed that terrestrial humic-like C1 and tyrosine-like C4 were the key factors explaining the abundance of the main bacterial clades. C1 was closely correlated with Verrucomicrobia, Actinobacteria, Alphaproteobacteria, Betaproteobacteria and Planctomycetes, and C4 was closely related to the latter two and to Bacteroidetes. At family level, the dominant families - Pelagibacteraceae (Alphaproteobacteria) and Gemmataceae (Planctomycetes) - were related to both allochthonous and autochthonous CDOM fluorophores but responded differently to the various CDOM components. Tryptophan-like C2 was significantly and positively correlated with Gemmataceae and Ellin6075 (Acidobacteria). Additionally, we found that the biomasses of Cyanophyta, terrestrial humic-like C1, tryptophan-like C4 and C5 were significantly related to the richness of heterotrophic bacterioplankton. Our results provide new insight into the relationship between bacteria and DOM optical dynamics although the mechanisms leading to these relationships need further experimental investigations.


Assuntos
Fenômenos Fisiológicos Bacterianos , Substâncias Húmicas/análise , Lagos/microbiologia , Microbiota/fisiologia , Fitoplâncton/fisiologia , China , Eutrofização , Processos Heterotróficos , Lagos/química
13.
Harmful Algae ; 84: 46-55, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31128812

RESUMO

Dolichospermum (formerly Anabaena) and Microcystis cause harmful cyanobacterial blooms in freshwater ecosystems worldwide. Input reduction of both nitrogen (N) and phosphorus (P) are commonly recognized as basic ways of controlling blooms, but little is known about the roles of nutrients and their using strategy among cyanobacteria in triggering the succession of diazotrophic to non-diazotrophic cyanobacteria. In this study, we investigated in situ responses of cyanobactria to ambient P status during the transition from Dolichospermum flos-aquae to Microcystis spp. in Lake Taihu and Lake Chaohu. While dominant in phytoplankton community, D. flos-aquae experienced P deficiency as evidenced by qualitative detection of extracellular phosphatase via enzyme labeled fluorescence (ELF). The percentage of ELF-labelled D. flos-aquae cells was 33% when it dominated the phytoplankton community, and was 78% when it co-dominated with Microcystis spp., indicating an increase in P deficiency. Meanwhile, no ELF-labelled Microcystis cells were observed while polyphosphate body (PPB) were present, suggesting that Microcystis spp. were not P deficient. Additionally, the percentages of Microcystis cells containing PPB showed an inverted "U-shaped" relationship with concentrations on soluble reactive phosphorus (SRP). To validate the field observation, a laboratory study of the monocultures of the dominant cyanobacteria was conducted. Extracellular alkaline phosphatase activity (APA) and PPB accumulation were regulated by P availability in monocultures of D. flos-aquae. Interestingly, no cell bound extracellular phosphatase was found on Microcystis aeruginasa even in the culture without P supply. Consistently, the expressions of phosphatase encoding gene phoX showed no differences among the treatments. The way in which PPB accumulation occurred in Microcystis spp. in response to P availability in the cultures was similar to that observed in the field, demonstrating a strategy of energy conservation over P accumulation. The competitive advantage of Microcystis spp. was displayed at low P concentrations: where it could rapidly uptake and store inorganic P, which also increased the P deficiency of the coexisting phytoplankton species. Responses of P-transport gene pstS confirmed this hypothesis. The physiological and molecular mechanisms mentioned above enable Microcystis to survive and proliferate in environment with low available P supply more efficiently. In conclusion, different cyanobacterial species have distinct ways of responding to P availability, suggesting that the control of cyanobacterial blooms by targeted nutrient reduction is largely dependent upon the dominant species. P reduction is more effective in controlling diazotrophic cyanobacteria than non-diazotrophic cyanobacteria.


Assuntos
Cianobactérias , Microcystis , Ecossistema , Nitrogênio , Fósforo
14.
Front Oncol ; 9: 211, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31032220

RESUMO

Background: Our previous work determined the correlation between high nuclear expression of hepatoma-derived growth factor (HDGF) and clinicopathological data of endometrial cancer (EC); however, the modulatory mechanisms and biological role of HDGF in EC have not been reported. Methods: Lentiviral particles carrying human HDGF short hairpin RNA (shHDGF-1, -2, and -3) vector and plasmids for HDGF, DDX5, and ß-catenin expression were, respectively introduced into EC cells to evaluate the effects and molecular mechanisms underlying EC cell proliferation, migration, invasion, and metastasis. Quantitative real time reverse transcription polymerase chain reaction (qRT-PCR) and western blotting were used to determine HDGF and DDX5 expression. Co-immunoprecipitation (co-IP), mass spectrometry, and an immunofluorescence co-localization study were conducted to explore the relationship between HDGF, DDX5, and ß-catenin. Immunohistochemistry was used to analyze the clinical associations between HDGF and DDX5 in EC. Results: Knocking down HDGF expression significantly decreased EC cellular proliferation, migration, invasion in vitro, as well as tumorigenesis and metastasis in vivo. Conversely, HDGF overexpression reversed these effects. Stable knockdown-based HDGF suppression activated the PI3K/AKT signaling pathway, along with downstream ß-catenin-mediated cell cycle and epithelial-mesenchymal transition signaling. Furthermore, co-IP combined with mass spectrometry and an immunofluorescence co-localization study indicated that HDGF interacts with DDX5, whereas ß-catenin was associated with DDX5 but not HDGF. Overexpression of DDX5 reversed the suppression of shHDGF. Immunohistochemistry analysis showed that high expression of DDX5 constituted an unfavorable factor with respect to the clinicopathological characteristics of EC tissues and that HDGF and DDX5 high expression (HDGF+/DDX5+) led to a worse prognosis for patients with EC (P < 0.001). In addition, we found that the expression of HDGF and DDX5 was positively correlated in EC tissues (r = 0.475, P < 0.001). Conclusion: Our results provide novel evidence that HDGF interacts with DDX5 and promotes the progression of EC through the induction of ß-catenin.

15.
Med Sci Monit ; 25: 2687-2694, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-30977468

RESUMO

BACKGROUND Research interest in endothelial nitric oxide synthase(eNOS) polymorphisms and atrial fibrillation (AF) has grown in last recent years, but the results of individual studies are inconsistent due to their small sample sizes. MATERIAL AND METHODS We searched databases for eligible studies on eNOS and AF, extracted the relevant data, and rigorously screened them according to inclusion and exclusion criteria. Then, we evaluated the study quality according to the Newcastle-Ottawa scale score, and we pooled the odds ratios (ORs) and 95% confidence intervals (CIs) by using a random-effects model or fixed-effects model based on inter-study heterogeneity. In addition, we performed subgroup analysis and sensitivity analysis and assessed publication bias. RESULTS According to the inclusion and exclusion criteria, we finally found 8 studies in this search. The recessive (OR=0.81; 95% CI=0.67 to 0.97; p=0.988; I²=0.0%) model showed that the eNOS 786T/C polymorphism was relevant to AF. We also found that the eNOS 786T/C polymorphism decreases the risk of AF, especially in white people (OR=0.81; 95% CI=0.67 to 0.97; P=0.023 for recessive model) and in the control population (OR=0.79; 95% CI=0.65 to 0.97; P=0.022 for recessive model). We found no obvious publication bias. CONCLUSIONS The eNOS gene loci 786T/C polymorphism is relevant to the risk of AF. Our results suggest that the 786T/C polymorphism significantly decreases AF risks in white people and control populations. Larger studies are required for further evaluation.


Assuntos
Fibrilação Atrial/enzimologia , Fibrilação Atrial/genética , Predisposição Genética para Doença , Óxido Nítrico Sintase Tipo III/genética , Polimorfismo de Nucleotídeo Único/genética , Alelos , Estudos de Casos e Controles , Humanos , Modelos Genéticos , Viés de Publicação , Fatores de Risco
16.
Sci Total Environ ; 669: 29-40, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30877958

RESUMO

In aquatic ecosystems, both phytoplankton and bacteria play pivotal roles. Based on 16S rRNA gene sequencing, considerable research focused on phytoplankton colony attached and free-living bacteria has revealed the close relationship between them, and indicated that the entire bacterial community mediates crucial biogeochemical processes in aquatic ecosystems. However, our understanding of their distribution patterns and response to environmental factors remains poor. Besides, picocyanobacteria, which were omitted from attached bacteria analysis, were reported to be important in cyanobacterial blooms. To explore the spatiotemporal variation of the entire bacterial community with their driving environmental factors and detect the relationships among them, we collected 61 water samples spanning one year and the entire Lake Taihu regions for surveying the entire bacterial community. Our results indicated: 1) seasonal variation of the bacterial community composition was stronger than spatial variation due to the clearly seasonal variation of Microcystis, Synechococcus (pico-cyanobacteria) and other bacteria (Actinomycetales, Pirellulaceae and Sphingobacteriaceae); 2) the spatial distribution of the bacterial community showed that different phyla were dominant in different regions; 3) the bacterial co-occurrence networks varied seasonally and were dominated by Microcystis, ACK-M1, Chthoniobacteraceae, Synechococcus, Pirellulaceae and Pelagibacteraceae; 4) phytoplankton density, chlorophyll a, water temperature and total nitrogen were the major factors that drove the spatiotemporal variation of bacterial community composition. This study revealed the seasonal succession and spatial distribution of the entire bacterial community in Lake Taihu, providing new insights into the relationship between water bloom-forming cyanobacterial species and other bacteria, and their response to environmental factors in eutrophic freshwater ecosystem.


Assuntos
Cianobactérias/fisiologia , Eutrofização , Lagos/microbiologia , Microbiota , Fitoplâncton/fisiologia , China , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Estações do Ano , Análise de Sequência de RNA
17.
Br J Pharmacol ; 176(9): 1341-1356, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30811584

RESUMO

BACKGROUND AND PURPOSE: Inflammasome-mediated pyroptosis is an important neuronal cell death mechanism. Previous studies reported that activation of melanocortin MC4 receptor exerted neuroprotection in several neurological diseases. Here, we have investigated the role of MC4 receptor activation with RO27-3225 in suppressing neuronal pyroptosis after experimental intracerebral haemorrhage (ICH) and the underlying mechanism. EXPERIMENTAL APPROACH: One hundred and sixty-nine male CD1 mice were used. ICH was induced by injection of bacterial collagenase into the right-side basal ganglia. RO27-3225, a selective agonist of MC4 receptor, was injected intraperitoneally at 1 hr after ICH. To elucidate the underlying mechanism, we used the specific MC4 receptor antagonist HS024 and NQDI-1, a specific inhibitor of the apoptosis signalling-regulating kinase 1 (ASK1). Neurological tests, Western blot, Fluoro-Jade C, TUNEL, and immunofluorescence staining were conducted. KEY RESULTS: Expression of MC4 receptor and the NOD-like receptor family, pyrin domain containing 1 (NLRP1) inflammasome in brain were increased after ICH. RO27-3225 treatment decreased neuronal pyroptosis and neurobehavioural deficits at 24 and 72 hr after ICH. RO27-3225 reduced the expression of p-ASK1, p-JNK, p-p38 MAPK, NLRP1 inflammasome, cleaved caspase-1, and IL-1ß after ICH. HS024 pretreatment prevented the effects of RO27-3225. Similar to RO27-3225, NQDI-1 alone improved neurological functions and down-regulated ASK1/JNK/p38MAPK expression after ICH. CONCLUSIONS AND IMPLICATIONS: RO27-3225 suppressed NLRP1-dependent neuronal pyroptosis and improved neurological function, possibly mediated by activation of MC4 receptor and inhibition of ASK1/JNK/p38 MAPK signalling pathways, after experimental ICH in mice. The MC4 receptor may be a promising therapeutic target for the management of ICH.

18.
J Sep Sci ; 42(5): 1088-1104, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30663861

RESUMO

Dendrobium huoshanense, a unique species in the genus Orchidaceae, is only found in China and is known as "mihu". Due to the lack of quality control, the use of D. huoshanense in the herbal market has been limited. In this study, methods based on thin-layer chromatography, high-performance liquid chromatography and high-performance liquid chromatography coupled with electrospray ionization multi-stage tandem mass spectrometry were used to identify the flavonoids in D. huoshanense and distinguish this species from other Dendrobium species. Using thin-layer chromatography, a characteristic band was observed for D. huoshanense, and this band was absent from the thin-layer chromatography plates of other Dendrobium species. Then, using high-performance liquid chromatography, nine peaks of flavonoids were observed in the chromatograms of ten batches of D. huoshanense. Ultimately, 22 flavonoids in D. huoshanense were identified by multi-stage tandem mass spectrometry, and 11 of these compounds are being reported from D. huoshanense for the first time. In addition, two compounds both with molecular weights of 710, were identified as being unique to D. huoshanense; one of these compounds, apigenin-6-C-α-L-rhamnosyl-(1→2)-ß-D-glucoside-8-C-α-L-arabinoside, was proven to be responsible for the characteristic thin-layer chromatography band of D. huoshanense. These analysis methods can be applied for the identification and quality control of D. Huoshanense.


Assuntos
Dendrobium/química , Flavonoides/análise , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Delgada , Dendrobium/classificação , Especificidade da Espécie , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
19.
Med Sci Monit ; 25: 150-156, 2019 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-30612135

RESUMO

BACKGROUND Fractional exhaled nitric oxide (FeNO) participates in the local defense of the upper respiratory tract. Abnormal FeNO level is directly related to the occurrence of nasal diseases. However, the clinical value of FeNO in the upper airway is limited, which greatly impedes the diagnosis and treatment of nasal diseases. Here, we assessed the level of FeNO and evaluated the diagnostic accuracy of FeNO for chronic rhinosinusitis. MATERIAL AND METHODS We enrolled 35 patients with confirmed nasal inflammation and 30 healthy subjects from December 2016 and June 2017. The FeNO level was measured using a fractional exhaled nitric oxide detector. The level of FeNO in patients with different clinicopathological factors was compared. The diagnostic potential of FeNO for chronic rhinosinusitis was evaluated by receiver operating characteristic (ROC) curve analysis. RESULTS FeNO level was significantly lower in patients with nasal inflammation than in healthy subjects (P<0.05). For nasal inflammation diagnosis, FeNO had the highest area under the curve (AUC) at 0.760, with a sensitivity of 93.30% and a specificity of 68.60%. FeNO level was significantly downregulated in chronic rhinosinusitis patients relative to chronic rhinitis patients (P<0.05). FeNO had a good ability to discriminate between chronic rhinosinusitis patients and chronic rhinitis patients, with higher AUC, sensitivity, and specificity of 0.760, 93.30%, and 68.60%, respectively. However, FeNO levels were not significantly different between different histological types of chronic rhinosinusitis (P>0.05). CONCLUSIONS Our results show that FeNO is a useful marker for discriminating chronic rhinosinusitis, and has potential to provide valuable information in the early diagnosis of chronic rhinosinusitis.


Assuntos
Testes Respiratórios/métodos , Óxido Nítrico/análise , Sinusite/diagnóstico , Adulto , Idoso , Biomarcadores , China , Doença Crônica , Expiração , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos Nasais , Curva ROC , Rinite , Sinusite/metabolismo
20.
Exp Ther Med ; 16(5): 4207-4212, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30402160

RESUMO

Identifying the predominant microbial species in patients with ethmoidal sinusitis is conducive to its successful treatment. The aim of the present study was to determine the microbial composition and the predominant fungal and bacterial species in patients with ethmoidal sinusitis. A sample was obtained from 3 patients with ethmoidal sinusitis and from the ethmoid sinus of 2 healthy volunteers. Those samples were sequenced using an Illumina/Solexa sequencing platform for mapping to human, fungal, and bacterial genomes. Fungal and bacterial expressions in those samples were analyzed through bioinformatics and statistical methods. The sequencing data revealed that the dominant fungal strains in the ethmoidal sinusitis samples compared with the healthy controls (8_S33 and 10_S9) were Aspergillus oryzae and Aspergillus flavus, and the dominant bacterial strains were Haemophilus influenzae and Haemophilus parainfluenzae. Together, these findings indicate that the development of ethmoidal sinusitis is associated with the presence of fungi and bacteria, which may benefit the successful diagnosis and treatment for patients with ethmoidal sinusitis.

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