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1.
Ecotoxicol Environ Saf ; 190: 110180, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31927195

RESUMO

This paper studied the allelopathic effect of Cylindrotheca closterium on the growth of Prorocentrum donghaiense, the model of harmful algal blooms in aquatic environment, by the co-culture tests and bioassay-guided fraction methods. The growth of P. donghaiense in co-cultures was observably suppressed by C. closterium, and P. donghaiense biomass in C/P = 3: 1 group increased slowly with a low growth rate of 0.18 d-1 after 4 days. Petroleum ether (PE) extract derived from C. closterium filtrates was isolated by C18 column and the allelopathy of all isolated fractions for P. donghaiense was investigated. After 96 h cultivation, the inhibition ratio of PE-Ⅲ and PE-Ⅷ fractions on P. donghaiense could reach up to 70.2% and 64.3% at the concentration of 10-fold when compared to control, while the other fractions displayed relatively low inhibitory effects on P. donghaiense. PE-Ⅲ and PE-Ⅷ fractions also decreased the chlorophyll content and maximum quantum yield of photosystem II (Fv/Fm) of P. donghaiense cells. The activities of superoxide dismutase (SOD), one of antioxidant enzymes, reduced around 8.3% and 13.7% following exposure to 2-fold PE-Ⅲ and PE-Ⅷ, and was significantly decreased following higher exposure concentrations. After 96 h of 10-fold PE-Ⅲ and PE-Ⅷ treatments, Catalase (CAT) activity reduced to 44.86% and 46.42% of that observed in the control group. At the same time, a significant increase in malondialdehyde (MDA) contents was observed. These findings suggested that PE-Ⅲ and PE-Ⅷ fractions contained main allelochemicals and possibly acted as promising algistatic agents for emergency handling of P. donghaiense blooms.

2.
Mar Pollut Bull ; 150: 110677, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31669981

RESUMO

A simple, sensitive and effective method was developed and validated for selective adsorption and quantitation of norfloxacin (NFX) from marine sediments and seawater samples using the novel molecularly imprinted silica polymers as sorbents followed by high-performance liquid chromatographic analysis with diode array detection (HPLC-DAD). The imprinted particles were characterized by different techniques and the molecular recognition for NFX was also investigated. Several parameters affecting the extraction efficiency of molecularly imprinted solid-phase extraction (MISPE) process were optimized. Three sediment and seawater samples from Weihai bay in China were analyzed and the results show that satisfactory recoveries (77.2-98.7%) were achieved in seawater samples with low relative standard deviation (RSD) values less than 6.89% (n = 3), and the recoveries in sediments were in the range of 75.5-91.7%. The limits of detection are respectivley 2 µg L-1 in seawater samples and 5 µg kg-1 in sediments.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31623216

RESUMO

High-polluting industries are important sources of pollutant emissions, and closely related to many environmental issues. High-polluting firms face the pressure to exploit technological innovation for improving their environmental operations. This paper explores the impact of corporate social responsibility and public attention on the innovation performance of high-polluting firms. Based on a sample of China's listed firms in high-polluting industries from 2011 to 2016, we use a panel data model to investigate the associations among corporate social responsibility, public attention and innovation performance. The results show that there is a positive association between corporate social responsibility and innovation performance. There is a positive association between public attention and innovation performance as well. The pressure of regional economies can hinder innovation performance. Furthermore, in the subsample of state-owned enterprises, the association between public attention and innovation performance is more pronounced. Meanwhile, the corporate social responsibility of non-state-owned enterprises plays a stronger role for innovation performance, but its effect will be limited by the pressure of regional economies. Our results can help high-polluting firms implement the innovation strategies for obtaining more environmental benefits and achieving sustainable development.

4.
Front Neurol ; 10: 994, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31611838

RESUMO

Objective: Diffusion-weighted imaging (DWI)-Alberta Stroke Program Early CT Score (ASPECTS) is a simple, widely used method to estimate the size of the infarct. Our aim is to determine whether there is a relationship between DWI-ASPECTS and fluid-attenuated inversion recovery (FLAIR) vascular hyperintensity (FVH)-DWI mismatch and to better quantify FVH-DWI mismatch to assess the prognosis of cerebral infarction. Materials and Methods: A retrospective analysis of 109 patients with MCA stenosis or occlusion with cerebral infarction was performed by dividing this cohort into FVH-DWI match group and FVH-DWI mismatch group based on FVH and DWI results. The clinical and imaging data of these two groups of patients were reviewed and analyzed to identify associations between FVH-DWI mismatch and prognosis of patients for preservation of neurological function. Correlation between DWI-ASPECTS and FVH-DWI mismatch was also performed. Results: FVH-DWI mismatch was present in 66/109 (60.55%) patients, and FVH-DWI match was present in 43/109 (39.45%). Patients with FVH-DWI mismatch had higher DWI-ASPECTS (7.0 vs. 4.0, P < 0.001) and lower mRS at 3 months (3.0 vs. 4.0, P < 0.001) than patients without FVH-DWI mismatch. Multiple regression analysis suggested that DWI-ASPECTS (OR = 4.7, 95% CI = 2.5-9.2, P < 0.001) remained significantly associated with FVH-DWI mismatch. Two threshold points for DWI-ASPECTS of 3 and 8 can be used to distinguish whether there is a mismatch in FVH-DWI by smooth curve fitting. Conclusions: The DWI-ASPECTS score was an independent predictor of FVH-DWI mismatch. At DWI-ASPECTS ≤ 3, the FVH-DWI mismatch offers no prognostic value; whereas, at DWI-ASPECTS ≥ 8, the FVH-DWI mismatch had the highest prognostic value. DWI-ASPECTS can roughly determine whether there is a FVH-DWI mismatch in order to select optimal clinical treatment and accurately assess prognosis.

5.
Medicine (Baltimore) ; 98(41): e17493, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31593114

RESUMO

The aim of this study was to assess the bedside brain function monitoring of color density spectral array (CDSA) for early prognostic evaluation of coma patients in pediatric intensive care unit (PICU).Forty-two consecutive pediatric coma patients were enrolled. The individual conscious state was evaluated according to the Glasgow coma scale (GCS). CDSA parameters including CDSA pattern (CDSAP), sleep-wake cycle (SWC), sleep stage (SS), and drug-induced fast wave activity (DIFWA) were recorded. Three months later, prognosis was evaluated according to pediatric cerebral performance category (PCPC) score, based on which the patients were divided into FP-group (favorable prognosis) and PP-group (poor prognosis).The changeable type of CDSAP, appearance of SWC, SS, and DIFWA were significantly correlated with favorable prognosis. Both GCS and SWC were significantly correlated with the prognosis. However, there was substantial overlap in GCS between FP-group and PP-group. Although the absence of SWC was statistically an independent risk factor for poor prognosis but with a high false positive rate (0.143), a linear logistic regression showed the odds ratio of GCS for predicting prognosis was 0.93 (95% confidence interval: 0.48-1.80; P = .83) and that of SWC was 0.12 (95% confidence interval: 0.03-0.47; P = .03). Furthermore, the absence of SWC was correlated with poor prognosis in nonintracranial infection patients.Our study found that several CDSA factors are associated with prognosis of coma patients in PICU. SWC may be a potential indicator for evaluating the prognosis of coma patients in PICU.


Assuntos
Coma/diagnóstico , Monitores de Consciência/estatística & dados numéricos , Unidades de Terapia Intensiva Pediátrica/estatística & dados numéricos , Testes Imediatos , Adolescente , Criança , Pré-Escolar , Colorimetria/métodos , Colorimetria/estatística & dados numéricos , Feminino , Escala de Coma de Glasgow , Humanos , Lactente , Modelos Logísticos , Masculino , Valor Preditivo dos Testes , Prognóstico
6.
Mar Pollut Bull ; 149: 110502, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31425841

RESUMO

A novel sample pretreatment strategy for separation and detection of atrazine from seawater was established with molecular imprinting solid-phase extraction (MISPE). Cyromazine was used as dummy-template based on computational analysis to synthesize dummy-template molecularly imprinted polymers (DMIPs) as sorbent of MISPE for atrazine analysis. The DMIPs were irregular loose porous layered structure characterized by scanning electron microscopy and showed higher binding capacity than non-imprinted polymers through adsorption experiments. An offline MISPE procedure using DMIPs as sorbent coupled with high-performance liquid chromatograph was developed for separation and purification of atrazine from seawater samples. The recoveries of atrazine in the spiked seawater samples ranged from 86.7% to 98.6%, and the relative standard deviation was less than 4.07% (n = 3) under optimal conditions indicating that the proposed method was suitable for the detection of trace residual atrazine in seawater. In addition, no atrazine was detected in three seawater samples from Jiaozhou bay, China.

7.
Mar Pollut Bull ; 146: 591-597, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426197

RESUMO

A molecularly imprinted polymer (MIP) anchored on the surface of CdTe quantum dots (QDs) was fabricated and used as a fluorescent probe for sulfadiazine (SDZ) detection in seawater. CdTe QDs was used as photoluminescent material, SDZ as the template, 3-aminopropyltriethoxysilane (APTES) as the functional monomer and tetraethyl orthosilicate (TEOS) as the cross-linking agent. Characterizations of MIP-QDs were analyzed by Fourier transform infrared (FT-IR), Transmission electron microscopy (TEM) and Scanning electron microscope (SEM). The conditions were optimized for the detection of MIP-QDs to SDZ. The mechanism of fluorescence quenching was studied by UV-Vis absorption spectroscopy and fluorescence spectroscopy. Under optimal conditions, the fluorescence intensity of MIP-QDs decreased linearly between 4- and 20 µM SDZ with a good correlation coefficient of 0.995. The limit of detection is 0.67 µM and the recovery is between 91.8 and 109.4% with RSD lower than 3.9%. These results indicated that MIP-QDs for SDZ detection in seawater was developed successfully.


Assuntos
Compostos de Cádmio/química , Pontos Quânticos/química , Água do Mar/análise , Sulfadiazina/análise , Telúrio/química , Poluentes Químicos da Água/análise , Antibacterianos/análise , Corantes Fluorescentes/química , Limite de Detecção , Microscopia Eletrônica de Transmissão , Impressão Molecular/métodos , Polímeros/síntese química , Polímeros/química , Propilaminas/química , Silanos/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Mikrochim Acta ; 186(7): 428, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31187284

RESUMO

A straightforward method has been developed for selective separation of chloramphenicol (CAP) from marine sediment samples. Magnetic molecularly imprinted nanoparticles (NPs) of type Fe3O4@SiO2 were prepared via surface imprinting with CAP. The NPs were characterized by Fourier transform infrared spectroscopy, transmission electron microscopy and thermogravimetric analysis. They have perfect core-shell structure, excellent thermal stability, high affinity and selectivity to CAP. The imprinting factor and Scatchard analysis also reveal good specific recognition to the template. The imprinted NPs were applied as sorbents for fast and selective extraction of CAP from marine sediment samples. The experimental parameters affecting separation efficiency were optimized. Three marine sediment samples were analyzed. Following desorption with methanol/water (90/10,v/v), CAP was quantified by HPLC with DAD detection. The limit of detection is 0.1 µg L-1 with a good linear response between 0.1-20 mg L-1 of CAP concentration (R2 = 0.999, n = 3). The method exhibits satisfactory recoveries from spiked samples (77.9-102.5%) and has low relative standard deviations (<6.3%). The magnetic material can be used at least 5 times by the regeneration without any loss of selectivity and adsorption capability. Graphical abstract Schematic presentation of magnetic molecularly imprinted nanoparticles (MMIPs) as sorbent for fast extraction and chromatographic analysis of chloramphenicol (CAP) from marine sediments. CAP-MMIPs are synthesized by surface imprinting method using 3-methacryloxy propyl trimethoxy silane (MPS) as the silane coupling agent.

10.
Nanomaterials (Basel) ; 9(6)2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31159438

RESUMO

This paper presents the facile synthesis of two different morphologies of WS2 nanomaterials-WS2 hexagonal nanoplates and nanoflowers-by a sulfurization reaction. The phases and morphology of the samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The tribological performance of the two kinds of WS2 nanomaterials as additives in paraffin oil were measured using a UMT (Universal Mechanical Tester)-2 tribotester. The results demonstrated that the friction and wear performance of paraffin oil can be greatly improved with the addition of WS2 nanomaterials, and that the morphology and content of WS2 nanomaterials have a significant effect on the tribological properties of paraffin oil. The tribological performance of lubricating oil was best when the concentration of the WS2 nanomaterial additive was 0.5 wt %. Moreover, the paraffin oil with added WS2 nanoflowers exhibited better tribological properties than paraffin oil with added WS2 hexagonal nanoplates. The superior tribological properties of WS2 nanoflowers can be attributed to their special morphology, which contributes to the formation of a uniform tribo-film during the sliding process.

11.
Nano Lett ; 19(10): 6756-6764, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31203631

RESUMO

In extreme environments, such as at ultrahigh or ultralow temperatures, the amount of tape used should be minimal so as to reduce system contamination and unwanted residues. However, tapes made from conventional materials typically lose their adhesiveness or leave residues difficult to remove under such conditions. Thus, the development of more versatile, lightweight, and easily removable tapes for applications in such extreme environments has received considerable attention. Here, we report that horizontally superaligned carbon nanotube (SACNT) tapes can be used to provide perfect van der Waals (vdW) interface contacts over a wide range of temperatures (from -196 to 1000 °C), yielding outstanding adhesiveness with specific adhesion strengths up to ∼1.1 N/µg. With a surface density of only 0.5-5 µg/cm2, hundreds of times lighter than the vertically aligned CNT adhesives, the SACNT tapes can be cost-effectively provided in hundreds of meters. They have multipurpose adhesive abilities for versatile materials and are also easily separated from samples even after exposure to extreme temperature regimes. First-principles calculations confirm the mechanism of vdW adhesion and reveal that ultraflat and nanometer-thick SACNT tapes may yield far greater adhesive abilities. These SACNT tapes show great potential for use in mechanical bonding, electrical bonding, and thermal dissipation in electronic devices.

12.
Mar Environ Res ; 148: 19-25, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31077964

RESUMO

Allelopathy between algae is an ecological strategy that can facilitate or inhibit the occurrence of algal blooms. The role of allelopathic effects of marine microalgae Cylindrotheca closterium in other phytoplankton population dynamics are still limited. In the current study, the effects of cell-free filtrates of diatom Cylindrotheca closterium on two common dinoflagellates (Prorocentrum donghaiense and Prorocentrum cordatum), a chrysophyceae (Isochrysis galbana) and a diatom (Chaetoceros curvisetus) were investigated within controlled laboratory experiments. It was observed that the growth of P. donghaiense was significantly suppressed and approximately 80% cells disappeared after 8-d exposure, while the other three algae was less sensitive. P. donghaiense was very sensitive to the exudates of C. closterium from the stationary phase by comparing various percentage (10, 30, 50, 70 and 100%) of filtrates. In addition, the allelopathic effects of extracellular compounds of C. closterium extracted by three different organic solvents (ethyl acetate, chloroform and petroleum ether) on P. donghaiense were explored by determining cell density, chlorophyll content and maximum photosystem II (PSII) quantum yield (Fv/Fm). It was found that the compounds extracted by ethyl acetate and chloroform appeared to exhibit less toxicity on P. donghaiense than that of petroleum ether. The present results indicated that the allelochemicals released by C. closterium might be concentrated effectively in the petroleum ether extraction phase, which provided a new perspective for controlling the red tides of P. donghaiense in the East China Sea by means of the ecological inhibitors extracted.

13.
Mikrochim Acta ; 186(6): 362, 2019 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-31104121

RESUMO

A fluorescent nanoprobe consisting of CdTe quantum dots (QDs) and coated with molecularly imprinted layers was prepared and successfully applied to the determination of norfloxacin (NOR) in seawater and wastewater samples. The 3-mercaptopropionic acid capped QDs were prepared and then covered with a protective silica shell. A molecularly imprinted layer was finally synthesized around the silanized QDs using 3-aminopropyltriethoxysilane as functional monomer and norfloxacin as the template. Compared with the non-imprinted polymer, the fluorescence of the nanoprobe with imprinted polymer (measured at excitation/emission wavelengths of 300/596 nm) is strongly reduced in the presence of NOR, and the imprinting factor is 8.8. Under the optimal experimental conditions, the detection limit of the nanoprobe is 0.18 µM, and response is linear between 0.5 - 28 µM of NOR. The relative standard deviation of the detection of NOR is <7.2%. In order to evaluate the practicality of the probe, wastewater and seawater samples spiked with norfloxacin were analyzed by this method, and recoveries ranged from 96.2 - 106.0%. Graphical abstract Schematic presentation and fluorescence spectrum of fluorescent nanoprobe with selectivity for norfloxacin (NOR). CdTe quantum dots (QDs) are used as fluorescent carriers, 3-aminopropyltriethoxysilane (APTES) as template molecules, tetraethyl orthosilicate (TEOS) as crosslinking agent, and aqueous ammonia as initiator.

14.
J Sep Sci ; 42(12): 2100-2106, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30964224

RESUMO

A novel molecularly imprinted polymer based on graphene oxide was prepared as a solid-phase extraction adsorbent for the selective adsorption and extraction of cyromazine from seawater samples. The obtained graphene oxide molecularly imprinted polymer and non-imprinted polymer were nanoparticles and characterized by scanning electron microscopy. The imprinted polymer showed higher adsorption capacity and better selectivity than non-imprinted polymer, and the maximum adsorption capacity was 14.5 mg/g. The optimal washing and elution solvents for molecularly imprinted solid phase extraction procedure were 2 mL of acetonitrile/water (80:20, v/v) and methanol/acetic acid (70:30, v/v), respectively. The recoveries of cyromazine in the spiked seawater samples were in the range of 90.3-104.1%, and the relative standard deviation was <5% (n = 3) under the optimal procedure and detection conditions. The limit of detection of the proposed method was 0.7 µg/L, and the limit of quantitation was 2.3 µg/L. Moreover, the imprinted polymer could keep high adsorption capacity for cyromazine after being reused six times at least. Finally, the synthesized graphene oxide molecularly imprinted polymer was successfully used as a satisfied sorbent for high selectivity separation and detection of cyromazine from seawater coupled with high-performance liquid chromatography.

15.
Biochem Biophys Res Commun ; 511(3): 587-591, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30824183

RESUMO

BACKGROUND: Tungsten disulfide (WS2), which enjoyed a good potential to be a promising clinical theranostic agent for cancer treatment, is still subject to the tedious synthesis procedure. METHODS: Here, we reported a one-pot 'bottom-up' hydrothermal strategy for the fabrication of PEGylated WS2 nanoparticles (NPs). The WS2-PEG nanoparticles were characterized systematically. The CT imaging and photothermal therapy against tumor as well as biosafety in vitro and in vivo were also investigated. RESULTS: The obtained WS2-PEG NPs enjoyed obvious merits of good solubility and favorable photothermal performance. WS2-PEG NPs exhibited desirable photothermal ablation ability against cancer cells and cancer cell-bearing mice in vitro and in vivo. MTT assay and histological analysis demonstrated the low cytotoxicity and biotoxicity of WS2-PEG NPs, providing a valid biosafety guarantee for the coming biomedical applications. In addition, thanks to the obvious X-ray attenuation of W atom, the WS2-PEG NPs can also be served as a favorable contrast agent for CT imaging of tumors. CONCLUSION: WS2-PEG NPs has enjoyed a good potential to be a promising clinical CT-guided photothermal therapeutic agent against cancers.


Assuntos
Neoplasias Mamárias Animais/terapia , Nanopartículas/uso terapêutico , Polietilenoglicóis/uso terapêutico , Compostos de Tungstênio/uso terapêutico , Animais , Linhagem Celular Tumoral , Feminino , Hipertermia Induzida , Neoplasias Mamárias Animais/diagnóstico por imagem , Camundongos , Nanomedicina Teranóstica , Tomografia Computadorizada por Raios X
16.
Psychopharmacology (Berl) ; 236(7): 2173-2185, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30847567

RESUMO

Depression is a common but serious mental illness; meanwhile, it is also an inflammatory disorder. Toll-like receptor 4 (TLR4), as the pattern recognition receptor, has been shown to play a vital role in neuroinflammation. The nucleotide binding and oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome acts as an important signaling molecule downstream of TLR4 and can promote the maturation of inflammatory cytokines, such as interleukin-1ß (IL-1ß). Tetramethylpyrazine (TMP) is a natural compound with neuroprotective effects but with unknown mechanisms on its antidepressant-like effect. In this study, we hypothesized that TMP ameliorates depression may be through the inhibition of the TLR4-NF-κB-NLRP3 signal pathway. Our results have shown that chronic unpredictable mild stress (CUMS) that induced the decreased sucrose preference and increased immobile time was prominently reversed by TMP and fluoxetine. Additionally, we also found that CUMS induced the upregulation of proinflammatory cytokines; TLR4 and NLRP3-associated proteins were significantly suppressed by TMP in the prefrontal cortex and hippocampus. TMP also exhibited potent antioxidant effects and increased the monoamine levels in the serum and brain, such as increasing the activity of SOD and GSH-Px, and reducing the activity of MDA in the serum, and elevating the 5-HT and NE concentration in the serum and brain. Moreover, treatment with Cli-095 (TLR4 inhibitor) also markedly inhibited CUMS-induced depression-like behaviors. Taken together, our findings suggested that TMP exerted a potential antidepressant-like effect in CUMS mice, and the molecular mechanisms may relate to inhibit the TLR4-NF-κB-NLRP3 signaling pathway in the brain.


Assuntos
Depressão/tratamento farmacológico , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Pirazinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Citocinas/antagonistas & inibidores , Citocinas/metabolismo , Depressão/metabolismo , Depressão/psicologia , Relação Dose-Resposta a Droga , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Inflamassomos/antagonistas & inibidores , Inflamassomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Pirazinas/farmacologia , Transdução de Sinais/fisiologia , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/metabolismo , Estresse Psicológico/psicologia , Receptor 4 Toll-Like/metabolismo , Vasodilatadores/farmacologia , Vasodilatadores/uso terapêutico
17.
J Geriatr Cardiol ; 16(2): 156-163, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30923548

RESUMO

Background: Few data on the combined effects of bifurcation and calcification on coronary artery disease (CAD) patients undergoing percutaneous coronary intervention (PCI) are available. This study evaluated the impact of main vessel (MV) calcification on the procedural and long-term outcomes in patients with CAD who underwent provisional single stent PCI. Methods: This is a multicenter, prospective, observational study. Patients with bifurcation lesions were enrolled at 10 PCI centers in China from January 2015 to December 2017. Intravascular ultrasound or optical coherence tomography was performed in all patients to evaluate the MV calcification. Patients were treated with provisional single stent strategy using drug eluting stents and followed-up at 1 month, 6 months and 12 months after discharge by telephone contact or outpatient visit. Repeated coronary imaging was performed within one year. We compared the procedural success rates in MV and in side branch (SB), and target lesion failure (TLF), defined as a composite of cardiac death, non-fatal myocardial infarction, definite or possible stent thrombosis and target lesion revascularization between patients with and without MV calcification. Results: A total of 185 subjects were enrolled according to the inclusion and exclusion criteria of this study. MV calcification was detected in 119 (64.3%, calcification group) and not found in 66 (35.7%, non-calcification group) patients. The angiographic success rate of MV was 95.8% in the calcification group and 97.0% in the non-calcification group (P = 0.91); the angiographic success rate of SB was 32.8% in the calcification group and 53.0% in the non-calcification group (P < 0.05). During the one-year follow-up period, TLF occurred in 14 (11.8%) patients in the calcification group and in 13 (19.7%) in the non-calcification group (P = 0.31). Multivariate regression analysis showed the same result (HR = 1.23, 95% CI: 0.76-1.52, P = 0.47). Calcification on group had higher recurrent angina than non-calcification group (13.51% vs. 17.65%, P < 0.05). Conclusions: In patients with coronary bifurcation lesion treated with provisional one stent approach, calcification of MV is associated with lower SB procedural success rate, it could increase recurrence of angina; however, it was not associated with an increased risk of TLF.

18.
Environ Pollut ; 247: 883-889, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30731314

RESUMO

Microplastics pose a great threat to entire marine ecosystems, but little is known about their impacts on phytoplankton, especially for the harmful dinoflagellates. In this study, effects of micro polyvinyl chloride (mPVC) on the growth, chlorophyll content and photosynthetic efficiency of the dinoflagellate Karenia mikimotoi at different periods (0, 24, 48, 72 and 96 h) were assessed using gradient concentrations (0, 5, 25, 50 and 100 mg L-1) of mPVC with a size of 1 µm. PVC microplastics had dose-dependent adverse effects on K. mikimotoi growth, chlorophyll content and photosynthetic efficiency. The density of algal cell decreased with increasing mPVC concentrations and the highest inhibitory rate (IR) was 45.8% at 24 h under 100 mg L-1 of mPVC. The total chlorophyll content and chlorophyll content in a single algal cell decreased at 96 h and the ФPSⅡ and Fv/Fm decreased 25.3% and 17.1%, respectively. The SEM images provided an intuitive visual method to observe the behaviors and interactions between microplastics and microalgae. It was found from the SEM images that microalgae was wrapped by microplastic beads. The physical blockage and aggregation were also responsible for the cytotoxicity of K. mikimotoi. Our study clarified that PVC microplastics can reduce algal growth, chlorophyll content and photosynthetic efficiency, and it is beneficial to evaluate the possible impact of plastics on aquatic ecosystems.


Assuntos
Dinoflagelados/fisiologia , Cloreto de Polivinila/toxicidade , Poluentes Químicos da Água/toxicidade , Clorofila/metabolismo , Dinoflagelados/efeitos dos fármacos , Microalgas/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Fitoplâncton/crescimento & desenvolvimento , Plásticos/toxicidade
19.
Sci Total Environ ; 660: 269-276, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30640095

RESUMO

Allelopathy has been regarded as chemical weapons for marine phytoplankton that enhanced competition ability in stressful conditions, especially during blooms. In a previous study, Chaetoceros curvisetus achieved growth advantage to Skeletonema costatum by producing allelochemicals. However, C. curvisetus allelochemicals have never been isolated and characterized until now. In this study the extraction and purification conditions were systematically optimized and C. curvisetus filtrate extracts were used to assess bioactive effects on the growth of S. costatum. The preliminary results showed that filtrates of C. curvisetus in exponential phase extracted under a temperature lower than 50°C could ensure a stronger activity of allelochemicals. Ethyl acetate extraction showed significant allelopathic effect and the wavelength of characteristic absorption was 255-260nm. Then C. curvisetus allelochemicals were isolated by Si-SPE, Sephadex-25 columns and C18 column and identified by HPLC-electrospray time-of-flight mass spectrometry (ESI TOFMS). It was found that the molecular weight of C. curvisetus allelochemicals was 314 and the allelochemical was supposed to be 2- ((2-cyanophenyl) amino)-2-oxoethyl,3-cyclohexyl propanoate.


Assuntos
Diatomáceas/metabolismo , Dinoflagelados/crescimento & desenvolvimento , Feromônios/metabolismo , Cromatografia Líquida de Alta Pressão , Dinoflagelados/metabolismo , Fitoplâncton/crescimento & desenvolvimento , Fitoplâncton/metabolismo
20.
J Altern Complement Med ; 25(1): 79-85, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30183329

RESUMO

OBJECTIVE: Nail biting leads to a variety of health issues. Habit reversal treatment is a major approach to cease nail biting, but is often ineffective since patients continue to suffer from anxiety, a major trigger. This study investigated whether the potential anxiety relief provided by auricular acupressure could improve the efficacy of habit reversal treatment, as evidenced by improved stomatological and other outcomes. METHODS: In a pragmatic, randomized, crossover, pilot clinical trial, 83 nail biters (8-12 years old) received habit reversal treatment in combination with either auricular acupressure intended to reduce anxiety (Method A) or placebo auricular acupressure (Method B). The alternative protocol was employed after a two-month washout period. The primary outcome measured was the 41-item child self-reported version of the Screen for Child Anxiety Related Emotional Disorders, while the secondary outcomes were the nail growth status (NS), which represented the fingernail growth of each finger during habit reversal treatment, simplified plaque index (SPI), and the simplified gingival index (SGI) as measures of oral health. A paired sample t-test was used to assess the differences between Methods A and B, and the differences in the anxiety scores, NS, SGI, and SPI between the baseline and each time point. RESULTS: Forty-one children successfully completed both arms of the treatments and attended all appointments. There were significant differences in the efficacy of habit reversal treatment, the anxiety score, the nail status, and the SGI in favor of Method A (p < 0.001). CONCLUSION: Auricular acupressure appears to improve the efficacy of habit reversal treatment, likely by reducing anxiety.


Assuntos
Acupressão , Acupuntura Auricular , Hábito de Roer Unhas/terapia , Ansiedade/terapia , Criança , Feminino , Humanos , Masculino , Projetos Piloto
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