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1.
Clin Cardiol ; 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31925816

RESUMO

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is a fundamentally new procedure for the treatment of native aortic regurgitation (AR). The number of cases needed to gain proficiency with the procedure is unknown. HYPOTHESIS: This study aimed to evaluate the learning curve for TAVR for native AR. METHODS: This study retrospectively reviewed a prospective database from 134 consecutive native AR patients who underwent the J-valve TAVR system, which performed by a single team interventional cardiologist. The cumulative sum (CUSUM) method was used to analyze the learning curve. Patients were divided into two groups in chronological order, defined by the surgeon's early (group 1: the first 52 cases) and skilled (group 2: the next 82 cases) experience. Demographic data, intraoperative characteristics, and short-term surgical outcomes were compared between the two groups. RESULTS: CUSUM plots revealed decreasing procedure time and fluoroscopy time after patients 52 and 43, respectively. The patient date consistently demonstrated that high-risk scores and major perioperative parameters were comparable between the two groups. The use of contrast dye (group 1, 94.22 ± 30.07 mL; group 2, 70.43 ± 15.02 mL, P<.05), total procedure time (group 1, 84.96 ± 17.76 minutes; group 2, 59.95 ± 12.83 minutes, P<.05), and fluoroscopy time (group 1, 11.52 ± 3.81 minutes; group 2, 6.47 ± 1.53 minutes, P<.05) were significantly reduced in group 2. The overall device success rate in group 1 was 96.2% vs 96.3% in group 2 and remained high (P = 1.0). The overall 30-day mortality was 3.8% in group 2 (group 1, 0 to group 2, 3.8%; P = .16). The complications rate, such as pulmonary hypertension, chronic kidney disease, and coronary artery disease were higher in group 2. CONCLUSIONS: For a surgeon without previous TAVR experience, 52 cases of performance is the minimal requirement to gain the proficiency of TAVR for native AR. The skilled surgeons have been observed with reduced procedural time, fluoroscopy times, radiation exposure dose, and contrast volume usage. However, the overall prognosis was not significantly different between the two groups.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31916848

RESUMO

Background: Abnormal expression of circular RNA (circRNA) has been shown to play an important role in the progression of cancer. However, the role of circRNAs on nonsmall cell lung cancer (NSCLC) remains largely unknown. This study aims to reveal the effects and potential mechanisms of circRNA on NSCLC cell proliferation and apoptosis. Materials and Methods: Real-time quantitative polymerase chain reaction was used to detect the expression of circ_0014130 in NSCLC tissues and cells. After silencing circ_0014130 in NSCLC cells H1299 and A549, MTT assay or flow cytometry was performed to analyze the proliferation or the apoptosis of cells, respectively. The relationships between circ_0014130, miR-142-5p, and insulin-like growth factor (IGF)-1 were validated by dual-luciferase reporter system and RNA pull-down. Western blot was used to detect the protein level of IGF-1 after the interference with circ_0014130 in NSCLC cells. Results: Circ_0014130 was abnormally highly expressed in NSCLC tissues and cells. After shRNA interfering circ_0014130 of NSCLC cells H1299 and A549, the NSCLC cell proliferation was inhibited and the cell apoptosis was promoted. By dual-luciferase reporter system and RNA pull-down assays, circ_0014130, miR-142-5p, and IGF-1 were confirmed to interact directly. After the transfection with si-circ_0014130 in NSCLC cells, the protein level of IGF-1 was reduced, and the cell proliferation was inhibited and the cell apoptosis was promoted, whereas these effects were reversed after cotransfection with miR-142-5p inhibitor. Conclusion: Our results indicated that the silencing circ_0014130 inhibited NSCLC cell proliferation and promoted cell apoptosis by upregulating miR-142-5p and downregulating IGF-1 expression. This might provide new strategies for future diagnosis and treatment of NSCLC.

3.
Europace ; 22(1): 90-99, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31909431

RESUMO

AIMS: We aimed to investigate the safety of discontinuing oral anticoagulation (OAC) therapy after apparently successful atrial fibrillation (AF) ablation, using data from the Chinese Atrial Fibrillation Registry study. METHODS AND RESULTS: We identified 4512 consecutive patients who underwent successful AF ablation between August 2011 and December 2017. Of them, 3149 discontinued OAC 3 months post-ablation (Off-OAC group) and 1363 continued OAC beyond this period (On-OAC group). Regular follow-up examinations were undertaken to detect AF recurrence, monitor OAC therapy, and measure clinical outcomes. Primary outcomes included thromboembolic and major bleeding (MB) events experienced beyond 3 months after ablation. Low thromboembolic and MB event rates were noted in the on-treatment analysis. The incidence rates for thromboembolism were 0.54 [95% confidence interval (CI) 0.39-0.76] and 0.86 (95% CI 0.56-1.30) per 100 patient-years, and that for MB events were 0.19 (95% CI 0.11-0.34) and 0.35 (95% CI 0.18-0.67) per 100 patient-years, for the Off-OAC and On-OAC groups over mean follow-up periods of 24.2 ± 14.7 and 23.0 ± 13.6 months, respectively. Similar results were observed in the intention-to-treat analysis. Previous history of ischaemic stroke (IS)/transient ischaemic attack (TIA)/systemic embolism (SE) [hazard ratio (HR) 3.40, 95% CI 1.92-6.02; P < 0.01] and diabetes mellitus (HR 2.06, 95% CI 1.20-3.55, P = 0.01) were independently associated with thromboembolic events, while OAC discontinuation (HR 0.71, 95% CI 0.41-1.23, P = 0.21) remained insignificant in multivariable analysis. CONCLUSIONS: This study suggests that it may be safe to discontinue OAC in post-ablation patients under diligent monitoring, in the absence of AF recurrence, history of IS/TIA/SE, and diabetes mellitus. However, further large-scale randomized trials are required to confirm this. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR-OCH-13003729. URL: http://www.chictr.org.cn/showproj.aspx?proj=5831.

4.
J Sep Sci ; 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31909566

RESUMO

Capillary electrochromatography, which combined the high selectivity of high performance liquid chromatography and the high separation efficiency of capillary electrophoresis, is an attractive separation tool. In this review, the developments on monolithic and open tubular capillary electrochromatography during 2017 to August 2019 are summarized. Considering the development of novel stationary phases is the most active research field in capillary electrochromatography, monolithic capillary electrochromatography is classified according to the polymer-based and hybrid monolithic columns, while open-tubular capillary electrochromatography is categorized by cyclodextrin, silica, polymer, nanomaterials, microporous materials and biomaterials-based open tubular columns. This article is protected by copyright. All rights reserved.

5.
Neurotox Res ; 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31900897

RESUMO

To investigate the effects of gastrodin (GAS) on methamphetamine (MA)-induced conditioned place preference (CPP) in rats and explore its potential mechanisms. MA (10 mg/kg) was initially injected intraperitoneally (i.p.) in rats, after which they were administered either MA or saline alternately from day 4 to 13 (D4-13) for 10 days, followed by treatment with GAS (10 or 20 mg/kg, i.p.) on D15-21 for 7 days. The rats underwent CPP testing after MA and GAS treatment. In vitro, SH-SY5Y cells were exposed to MA (2.0 mM) for 24 h, followed by treatment with GAS (2.0 or 4.0 mM) for 24 h. The expression levels of PKA, P-PKA, CREB, and P-CREB proteins in the prefrontal cortex, nucleus accumbens, and ventral tegmental area of MA-induced CPP rats and in SH-SY5Y cells were detected by Western blot analysis. The MA-induced CPP rat model was successfully established. The administration of MA stimulated a significant alteration in behavior, as measured by the CPP protocol. After treatment with GAS, the amount of time rats spent in the MA-paired chamber was significantly reduced. Results also showed that MA increased the expression levels of PKA, P-PKA, CREB, and p-CREB proteins in the prefrontal cortex, nucleus accumbens, and ventral tegmental area of CPP rats and in SH-SY5Y cells (p < 0.05). GAS attenuated the effect of MA-induced CPP in rats and decreased the expression levels of proteins in vivo and in vitro. Our study suggests that GAS can attenuate the effects of MA-induced CPP in rats by regulating the PKA/CREB signaling pathway.

6.
Huan Jing Ke Xue ; 41(1): 14-22, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854899

RESUMO

We use daily aerosol particulate matter<10 µm (PM10) concentration data from 2006 to 2016 in Shanghai along with meteorological elements (wind and temperature), atmospheric stability, temperature inversion, and upper atmosphere circulation data, to analyze the variation characteristics of the PM10 concentrations and differences of the winter climate background. We establish a multivariate linear stepwise regression equation, and also compare and analyze differences in the upper atmospheric circulation by selecting the years with the highest and lowest PM10 concentrations. The results showed an oscillating downward trend in the annual average concentrations of PM10 in Shanghai, whereas seasonally, PM10 concentrations were relatively high in winter and showed two peaks with a low in between. PM10 concentrations were negatively correlated with the daily average wind speed and the daily mixing layer height at 20:00, and positively correlated with the frequency of northwest wind, the mean daily temperature, and the frequency of stable weathers and thermal inversion at 20:00. When the 500 hPa height field in the northern part of China was a positive anomaly in winter, a warm winter prevailed and led to high PM10 concentrations. When the 500 hPa height field was a negative anomaly, cold air frequently moved southward to result in relatively low temperatures, which caused relatively low PM10 concentrations. When the wind field at 850 hPa was easterly, the wind speed was relatively large and resulted in relatively low PM10 concentrations.

7.
Transl Stroke Res ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31833035

RESUMO

The blood-brain barrier (BBB) disruption leads to the vasogenic brain edema and contributes to the early brain injury (EBI) after subarachnoid hemorrhage (SAH). However, the mechanisms underlying the BBB damage following SAH are poorly understood. Here we reported that the neurotransmitter glutamate of cerebrospinal fluid (CSF) was dramatically increased in SAH patients with symptoms of cerebral edema. Using the rat SAH model, we found that SAH caused the increase of CSF glutamate level and BBB permeability in EBI, intracerebroventricular injection of exogenous glutamate deteriorated BBB damage and cerebral edema, while intraperitoneally injection of metabotropic glutamate receptor 1(mGluR1) negative allosteric modulator JNJ16259685 significantly attenuated SAH-induced BBB damage and cerebral edema. In an in vitro BBB model, we showed that glutamate increased monolayer permeability of human brain microvascular endothelial cells (HBMEC), whereas JNJ16259685 preserved glutamate-damaged BBB integrity in HBMEC. Mechanically, glutamate downregulated the level and phosphorylation of vasodilator-stimulated phosphoprotein (VASP), decreased the tight junction protein occludin, and increased AQP4 expression at 72 h after SAH. However, JNJ16259685 significantly increased VASP, p-VASP, and occludin, and reduced AQP level at 72 h after SAH. Altogether, our results suggest an important role of glutamate in disruption of BBB function and inhibition of mGluR1 with JNJ16259685 reduced BBB damage and cerebral edema after SAH.

8.
Eur J Pharmacol ; : 172856, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31836533

RESUMO

Saphenous vein grafts (SVG) patency is limited by intimal hyperplasia (IH) caused by endothelial dysfunction. This study aimed to explore the effect of placental growth factor (PlGF) on the endothelial function of SVG. In rat models of external jugular vein-carotid artery graft treated with PlGF or saline hydrogel, PlGF inhibited vein graft IH (day 28: 12.0 ±â€¯1.9 vs. 61.7 ±â€¯13.1 µm, P < 0.001), promoted microvessel proliferation (day 14: 33.3% 3+ vs. 50.0% 2+, P = 0.03), and increased nitric oxide (NO) production (P < 0.05 on days 1/3/5) and NO synthase (NOS) expression by immunohistochemistry. In human umbilical vein endothelial cells (HUVECs) cultured under hypoxia and treated or not with PlGF, PlGF restored the survival (50 ng/ml PlGF, 48 h: 91.7 ± 0.6% vs. 84.9 ± 0.5%, P < 0.01), migration (by Matrigel assay), and tube formation ability (junctions, tubules, and tubule total length; all P < 0.01) of HUVECs after hypoxia. PlGF increased NO production through increased eNOS expression (P < 0.05), without changes in iNOS expression. The mRNA expression of eNOS decreased after the addition of the PI3K inhibitor LY294002 (P < 0.05). PlGF promoted the protein expression of eNOS by up-regulating AKT, and the AKT and eNOS protein levels were decreased after adding LY294002 (all P < 0.05). In conclusion, PlGF is a candidate for the inhibition of IH in SVG after coronary artery bypass graft. The effects of PlGF are mediated by the upregulation of the eNOS mRNA and protein through the PI3K/AKT signaling pathway. PlGF promotes the secretion of NO by endothelial cells and thereby reduces the occurrence and development of IH.

9.
Chin J Nat Med ; 17(11): 871-880, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31831133

RESUMO

Dahuang-Gancao decoction (DGD) is a classical formula, which is commonly used for reliving constipation in Chinese clinic. The aim of this study was to investigate the pharmacodynamic, pharmacokinetic and tissue distribution alternations of DGD in normal and constipation mice. DGD exhibited stronger purgative effect in constipation mice by the increased fecal excretion and reduced first defection time compared with normal mice. The Cmax, AUC0-t and MRT0-t of rhein, aloe-emodin, rhein-8-O-ß-D-glucoside, sennoside A, and glycyrrhizic acid as main bio-active components in DGD were markedly increased in constipation mice. The tissue distribution of the analytes in constipation mice were higher than those in normal mice with rhein > rhein-8-O-ß-D-glucoside > aloe-emodin > glycyrrhizic acid > emodin in liver, and glycyrrhizic acid > rhein-8-O-ß-D-glucoside > liquitin > sennoside A > rhein > aloe-emodin > emodin in colon. The kidney concentrations of the analytes showed a descending order of rhein > rhein-8-O-ß-D-glucoside > sennoside A > glycyrrhizic acid > aloe-emodin > emodin, most of them were higher while rhein was lower in constipation mice than normal mice. The higher exposure of the anthraquinones in plasma, liver and colon may result in the stronger purgative effect in the constipation mice than normal mice. Rhein is mainly excreted through the kidney, the decreased level of rhein in constipation mice may explain the alleviated side effects. Accumulation of glycyrrhizic acid in colon may related with the moderate property of licorice. These results provided the experimental basis for understanding the therapeutic effects and metabolite profile of DGD.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31789948

RESUMO

BACKGROUND: To explore the risk factors and prognostic factors related to the acute-on-chronic liver failure (ACLF) occurrence and adverse outcome after withdrawal of nucleos(t)ide analogs (NAs) in chronic hepatitis B (CHB) patients. METHODS: Hospitalized CHB patients with relapse after NAs withdrawal at our medical center were retrospectively included in the present study from January 2011 to May 2018. Logistic regression, Cox regression analysis, Kaplan-Meier log-rank test, and area under the receiver operating characteristic curves (AUROC) were used. RESULTS: A total of 389 CHB patients (including 46 ACLF patients) were included. Their median age was 48.0 years; 315 patients were male and 74 were female. The age ≥30 years and HBVDNA ≤1000 copies at admission in logistic regression were the independent risk factors for ACLF after NAs withdrawal in CHB patients. In patients who developed ACLF, only the model of end-stage liver disease combining serum natrium concentration (MELD-Na) score and relapse after Lamivudine (LAM) cessation in the Cox multivariate regression analysis were independent predictors for 12-week mortality. The artificial liver support system (ALSS) showed no improvement in the 12-week survival of ACLF patients. We further defined 22.35 as the optimal cutoff value of MELD-Na score to predict 12-week mortality for ACLF patients, with the AUROC of 0.817, a sensitivity of 76.5%, and a specificity of 75.9%. CONCLUSION: The age ≥30 years and HBVDNA ≤1000 copies at admission strongly correlate with occurrence of ACLF, and higher MELD-Na score and relapse after LAM withdrawal are closely related with 12-week mortality among patients with ACLF after NAs withdrawal.

11.
J Obstet Gynaecol ; : 1-6, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31790312

RESUMO

Preeclampsia (PE) is a serious gestational idiopathic hypertensive disease, threatening both maternal and foetal safety. As a systemic disease, the initial-onset symptoms (IOSs) and clinical manifestations of PE can vary widely from patient to patient. However, a lack of evidence-based data on IOS and their relationship to their corresponding clinical features and pregnancy outcomes persists. We hypothesised that there would be a significant difference between the morbidity time, subsequent organ dysfunction and the status of mother and foetus in PE patients with different IOS. Moreover, early identification of the characteristics of the PE patients with different IOS could improve pregnancy outcomes through individualised prevention or intervention. This study aimed to analyse maternal and foetal condition and pregnancy outcomes of PE patients with different IOS, and to explore the disease progression and characteristics of maternal and foetal outcomes for different IOS, so as to provide the basis for future maternal and foetal monitoring of PE patients.Impact statementWhat is already known on this subject? In 2013, the American College of Obstetricians and Gynecologists revised their definition of PE, sparking a heated debate. Subsequently in 2015, China updated its guidelines to define PE as hypertensive pregnancy accompanied by involvement of any other organ or organ system, to include the heart, lungs, liver and kidneys, among others. However, IOS can be varied in PE, so the maternal management and foetal monitoring should be classified through different IOS. No evidence-based data on IOS in PE patients exist.What the results of this study add? Significant differences in mean morbidity times and mean delivery times were demonstrated among patients with different IOS; medians of the interval from morbidity to delivery were between 4 and 6 weeks. Significant differences in laboratory values were found in patients with different IOS. In patients that did not present with proteinuria as an IOS, 89.1% experienced proteinuria following diagnosis. Patients with the most severe complications presented with hypertension as an IOS. Follow-up visits demonstrated different foetal weight medians.What the implications are of these findings for clinical practice and/or further research? IOS could be an indicator to help evaluate the potential for different maternal and foetal complications and PE outcomes. Moreover, the duration of treatment for PE maybe 4-6 weeks.

12.
Int J Nanomedicine ; 14: 8693-8706, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31806965

RESUMO

Background: Although tantalum (Ta)-based coatings have been proven to have good antibacterial activity, the underlying mechanism and in vivo biological performance remain unclear, which are essential for the clinical application of Ta-coated biomaterials as dental implants. Purpose: The main objective of this study is to investigate the antibacterial activity of Ta-modified titanium (Ti) implants against peri-implantitis-related microbes and the potential molecular mechanisms. Methods: Fusobacterium nucleatum and Porphyromonas gingivalis were selected to evaluate the antibacterial activity and potential antibacterial mechanism of Ta modification. The in vivo biocompatibility of Ta-modified implants was also evaluated. Results: The results showed that Ta-modified surface performed excellent antimicrobial activity against Fusobacterium nucleatum and Porphyromonas gingivalis. Micro galvanic might be formed between the incorporated Ta and the Ti base, which could consume the protons and result in decreased ATP synthesis and increased ROS generation. The gene expression of bacterial virulence factors associated with cellular attachment, invasion and viability as the target of ROS was downregulated. Importantly, in vivo biological studies showed that Ta modification significantly promoted the osseointegration of implants by stimulating the expression of bone-forming proteins. Conclusion: This study may provide some insights into clinical applications of Ta-coated Ti implants, especially in possibly infected situations.

13.
Huan Jing Ke Xue ; 40(11): 5073-5081, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854576

RESUMO

To determine the distribution characteristics of heavy metal pollution in farmland soils and related influencing factors in the Taige canal valley, and guarantee soil environmental quality and safety of agricultural products, 118 topsoil samples were collected from the Taige canal valley's farmland soils, and contents of chromium (Cr), mercury (Hg), arsenic (As), copper (Cu), zinc (Zn), nickel (Ni), lead (Pb), and cadmium (Cd) were measured. A single factor index and comprehensive index were used to assess soil heavy metal contamination with the soil background value of the Taihu Lake basin as the evaluation standard. The multivariate statistical analysis and the geostatistical analysis were combined to identify and apportion the pollution sources of soil heavy metals. The results showed that:The average concentrations of Cr, Hg, As, Cu, Zn, Ni, Pb, and Cd in soils were 63.25, 0.25, 7.83, 35.24, 77.25, 31.48, 38.37, and 0.16 mg·kg-1, respectively, all of which except for Cr and As were higher than the local soil background values. The content of each heavy metal in most soil samples were lower than the risk screening values for soil contamination of agricultural land. The comprehensive index showed that the degree of pollution of soil heavy metals were at a slightly polluted level in 87.29%, moderately polluted level in 5.93%, and severely polluted level in 6.78% of the sampling. Hg, Cu, Zn, Pb, and Cd in the watershed soil were affected by agricultural activities and atmospheric deposition. Cr and Ni were affected by the parent material and industrial production activities. As was mainly derived from the parent material.

14.
Huan Jing Ke Xue ; 40(8): 3577-3587, 2019 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854763

RESUMO

In order to study changes in benthic diatom communities and their relationships with environmental factors during different hydrological periods, 32 sites were sampled in the main stream of the Three Gorges Reservoir during the non-storage period (July 2015 to September 2015) and the storage period (December 2015 to March 2016). Results showed that there were significant differences in water temperature (WT), underwater light intensity (PAR), pH, conductivity (Spc), dissolved oxygen (DO), redox potential (ORP), turbidity (Tur), transparency (SD), flow rate (v), and permanganate index between the storage and non-storage periods. Ninety-six species of benthic diatoms, belonging to 28 genera, were identified during the two hydrological periods. Thirteen dominant species and three dominant species were identified during the non-storage period and the storage period, respectively, suggesting that some differences existed in the composition and distribution of dominant species between the two periods. However, Melosira varians, an α-polluting and eutrophic species, was dominant during both of the hydrological periods. Redundancy analysis (RDA) found that pH, flow rate, and orthophosphate (PO43--P) were the main environmental factors affecting the composition of benthic diatom communities, and a significant difference was found between up- and down-stream areas during the non-storage period. In comparison, water temperature, turbidity, permanganate index, and dissolved oxygen (DO) were the main environmental factors influencing the patterns of benthic diatoms communities, for which an insignificant difference was observed between up- and down-stream areas during the storage period. These results suggest that water storage in the Three Gorges Reservoir has an important impact on the composition of benthic diatom communities, and that this results in a change in community structure.

15.
Huan Jing Ke Xue ; 40(12): 5593-5603, 2019 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854632

RESUMO

The composition of municipal solid waste (MSW) in landfills is complex; additionally, the waste stored in landfills continues to generate greenhouse gases, odors, and ground water pollutants even during the post-closure stage. Therefore, landfills are considered key fields of urban eco-environmental remediation. In this context, it is crucial to understand the storage, composition, physical, and chemical characteristics of waste, as well as its potential environmental impacts. However, very few studies have discussed these topics in detail. In this work, we focused on the Guangdong-Hong Kong-Macao Greater Bay Area (GBA), which has the highest urbanization rate and population density of all China. The generation, stock, physical components, and key elements of MSW in eleven cities of the GBA were analyzed based on both the scientific literature and statistical data. The main results are as follows:① the total amount of MSW produced by the cities was of 26.4 Tg in 2017, with an average annual increment of 0.8 Tg; moreover, the most used disposal method was the sanitary landfill (58.9% of the total); ② the total amount of MSW disposed in the landfills was equal to 230.1 Tg[including mainly food waste (109.6 Tg), plastic (38.9 Tg), and paper (29.6 Tg)]; ③ between 2001-2017, a total of 50.0 Tg of carbon were input in the landfills in the form MSW, of which 7.1 Tg of carbon were emitted as gas and 1.5 Tg were discharged as leachate; moreover, the total landfill carbon stock was equal to 41.4 Tg. Overall, this study provides fundamental data that can be used to determine the environmental impacts of MSW landfills and implement the eco-environmental remediation of urban landfill sites in the GBA.


Assuntos
Eliminação de Resíduos , Resíduos Sólidos , China , Cidades , Alimentos , Hong Kong , Macau , Instalações de Eliminação de Resíduos
16.
Huan Jing Ke Xue ; 40(7): 3099-3107, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854707

RESUMO

In order to explore the composition of epiphytic algae and its related environmental factors, 12 sampling sites in the natural reaches and the backwater reaches (including perennial backwater sections and fluctuating backwater sections) were investigated among tributaries of the Caotang River, the Meixi River, and the Daxi River in the Fengjie district of the Chongqing section of the Three Gorges Reservoir under different hydrological regimes (i.e., storage and non-storage periods). Results showed that 103 species of epilithic algae belonging to 45 genera and 4 families are found in the 3 tributaries. This included 67 species belonging to 34 genus in the natural sections and 82 species (64 species in perennial backwater sections and 41 species in fluctuating backwater sections) belonging to 34 genera in the backwater sections. During the storage period, the dominant species in the natural sections were Melosira varians, Cocconeis placentula, Diatoma vulgure, Gyrosigma scalproides, and Oscillatoria tenuis, while the dominant species in the backwater sections were M. varians, Cymbella affinis,D. vulgure, Eucapsis alpina, and M. granulata. During the non-storage period, the dominant species in the natural sections were M. varians, C. affinis, and C. placentula, whereas the dominant species in the backwater sections were O. princeps, O. rupicola,O. formosa, Synedra acus, Ulothrix sp., Merismopedia elegans, and O. tenuis. These results suggested that the compositions of dominant species showed significant differences during the non-storage period, while little difference was found during the storage period. In addition, the dominant species did not show a significant change in the natural sections, but a marked difference was observed in the backwater sections. Similar dominant species were observed in both perennial and fluctuating backwater sections during the non-storage period, but significantly different dominant species were found during the storage period. Redundancy analysis suggested that the composition of epilithic algae was influenced by different environmental factors, such as temperature, electrical conductivity, pH, total nitrogen, and total phosphorus. Indeed, changes in the cell densities of dominant algae at the different sites were mainly affected by temperature and the concentrations of nitrogen and phosphorus. These results suggest that the different hydrological regimes had an important role not only on the reservoir water environment, but also the dynamics of epilithic algal communities.


Assuntos
Cianobactérias/fisiologia , Monitoramento Ambiental , Rios , China , Nitrogênio/análise , Fósforo/análise , Estações do Ano
17.
Zhongguo Zhong Yao Za Zhi ; 44(22): 4857-4863, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31872593

RESUMO

To prepare Helix aspersa muller-paeonol nanogel( PAE-HAM-Gels) with anti-proliferative scar effect,evaluate its skin penetration,retention and irritation,and to investigate its prevention and treatment effect for hypertrophic scar in rabbit ears. The dermal retention,transdermal rate and cumulative permeability of paeonol were investigated in vitro by using the modified Franz diffusion cell and the abdominal skin of suckling pigs,SD rats and KM mice,respectively,and the in vitro permeation curves were drawn. The normal skin of the back of New Zealand rabbits was continuously treated with PAE-HAM-Gels for 7 days,and the physiological state of the skin was observed under light microscope after HE staining by using homologous left and right contrast method. The hypertrophic scar model in rabbit ears was established,and the New Zealand rabbits were randomly divided into blank group,model group,positive drug group,PAE-Gels group and PAE-HAM-Gels group. After 28 days of administration,the scar hyperplasia rate and scar elevation index( SEI) of each group were calculated; the scar tissues were taken and stained with Masson for observation of collagen fibers and muscle fibers hyperplasia under light microscope,and the expression level of TGF-ß1 in each group was detected. The Qnof PAE-HAM-Gels in aqueous solution was in line with the Higuchi equation,and its transdermal rate,cumulative permeation and dermal retention in different animal skins were all higher than those of PAE-Gels. The skin of the drug-administered group was intact,without erythema,edema or other phenomena; under light microscope,the subcutaneous tissue and the epidermal cells were neatly arranged with uniform thickness,which showed no difference from the blank group. The scar hyperplasia rate of the PAE-HAM-Gels group was 62. 50%; SEI was 2. 17±0. 33 and TGF-ß1 was( 815. 4±34. 69) ng·L~(-1),significantly different from those in model group( P<0. 01). Masson staining showed that as compared with the model group,the number of collagen fibers and muscle fibers was small and the arrangement was loose and tidy in the PAE-HAM-Gels group,with regular arrangement of chondrocytes and a small number of inflammatory cells and microvessels.PAE-HAM-Gels have good transdermal properties and dermal retention without skin irritation,offering a promising therapeutic strategy for transdermal delivery during the prevention and treatment of hypertrophic scar in rabbit ears.


Assuntos
Acetofenonas/química , Cicatriz Hipertrófica , Orelha , /química , Animais , Camundongos , Coelhos , Ratos , Ratos Sprague-Dawley , Suínos
18.
Haematologica ; 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31857368

RESUMO

Remodeling of adipocyte morphology and function plays a critical role in prostate cancer development. We previously reported that leukemia cells secrete growth differentiation factor 15 (GDF15),which remodels the residual bone marrow (BM) adipocytes into small adipocytes and is associated with a poor prognosis in acute myeloid leukemia (AML) patients. However, little is known about how GDF15 drives BM adipocyte remodeling. In this study, we examined the role of the transient receptor potential vanilloid (TRPV) channels in the remodeling of BM adipocytes exposed to GDF15. We found that TRPV4 negatively regulated GDF15-induced remodeling of BM adipocytes. Furthermore, transforming growth factor-ß type II receptor (TGFßRII) was identified as the main receptor for GDF15 on BM adipocytes. PI3K inhibitor treatment reduced GDF15-induced pAKT, identifying PI3K/AKT as the downstream stress response pathway. Subsequently, GDF15 reduced the expression of the transcription factor Forkhead box C1 (FOXC1) in BM adipocytes subjected to RNA-seq screening and Western blot analyse. Moreover, it was also confirmed that FOXC1 combined with the TRPV4 promoter by the Chip-qPCR experiments, which suggests that FOXC1 mediates GDF15 regulation of TRPV4. In addition, an AML mouse model exhibited smaller BM adipocytes, whereas the TRPV4 activator 4α-phorbol 12,13-didecanoate (4αPDD) partly rescued this process and increased survival. In conclusion, TRPV4 plays a critical role in BM adipocyte remodeling induced by leukemia cells, suggesting that targeting TRPV4 may constitute a novel strategy for AML therapy.

19.
Small ; : e1905902, 2019 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-31867892

RESUMO

Semiconducting nanowires offer many opportunities for electronic and optoelectronic device applications due to their unique geometries and physical properties. However, it is challenging to synthesize semiconducting nanowires directly on a SiO2 /Si substrate due to lattice mismatch. Here, a catalysis-free approach is developed to achieve direct synthesis of long and straight InSe nanowires on SiO2 /Si substrates through edge-homoepitaxial growth. Parallel InSe nanowires are achieved further on SiO2 /Si substrates through controlling growth conditions. The underlying growth mechanism is attributed to a selenium self-driven vapor-liquid-solid process, which is distinct from the conventional metal-catalytic vapor-liquid-solid method widely used for growing Si and III-V nanowires. Furthermore, it is demonstrated that the as-grown InSe nanowire-based visible light photodetector simultaneously possesses an extraordinary photoresponsivity of 271 A W-1 , ultrahigh detectivity of 1.57 × 1014 Jones, and a fast response speed of microsecond scale. The excellent performance of the photodetector indicates that as-grown InSe nanowires are promising in future optoelectronic applications. More importantly, the proposed edge-homoepitaxial approach may open up a novel avenue for direct synthesis of semiconducting nanowire arrays on SiO2 /Si substrates.

20.
ACS Nano ; 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31877250

RESUMO

Maintaining the rapid development of information technology by scaling down a metal-oxide semiconductor field-effect transistor faces two serious challenges. First, the gate field loses control of the channel as it continuously decreases. Second, the fundamental thermionic limit restricts the reduction in supply voltage. Thus, further scaling down necessitates alternative device structures and different switching mechanisms. Here, we report impact-ionization transistors (IITs) based on nanoscale (∼30 nm) vertical graphene/black phosphorus (BP)/indium selenide (InSe) heterostructures. By facilitating the carrier multiplication of the ballistic impact-ionization process as the internal gain mechanism in sub-mean-free-path (sub-MFP) channels, the IITs exhibit a low average subthreshold swing (SS < 1 mV/dec) over five current levels. High stability (>10 000 cycles) and small hysteresis (<1%) switching properties are also obtained. The experimental demonstration of such transistor combining steep SS, high ON-state current density, reliable robustness, miniature footprint, and low bias voltage approaches fulfillments of targets for next-generation devices in the International Technology Roadmap for Semiconductors.

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