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1.
BMC Anesthesiol ; 24(1): 172, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720250

RESUMO

BACKGROUND: Low immune function after laparoscopic total gastrectomy puts patients at risk of infection-related complications. Low-dose naloxone (LDN) can improve the prognosis of patients suffering from chronic inflammatory diseases or autoimmune diseases. The use of LDN during perioperative procedures may reduce perioperative complications. The purpose of this study was to examine the effects of LDN on endogenous immune function in gastric cancer patients and its specific mechanisms through a randomized controlled trial. METHODS: Fifty-five patients who underwent laparoscopic-assisted total gastrectomy were randomly assigned to either a naloxone group (n = 23) or a nonnaloxone group (n = 22). Patients in the naloxone group received 0.05 µg/kg-1.h- 1naloxone from 3 days before surgery to 5 days after surgery via a patient-controlled intravenous injection (PCIA) pump, and patients in the nonnaloxone group did not receive special treatment. The primary outcomes were the rates of postoperative complications and immune function assessed by NK cell, CD3+ T cell, CD4+ T cell, CD8+ T cell, WBC count, neutrophil percentage, and IL-6 and calcitonin levels. The secondary outcomes were the expression levels of TLR4 (Toll-like receptor), IL-6 and TNF-α in gastric cancer tissue. RESULTS: Compared with the nonnaloxone group, the naloxone group exhibited a lower incidence of infection (in the incision, abdomen, and lungs) (P < 0.05). The numbers of NK cells and CD8+ T cells in the naloxone group were significantly greater than those in the nonnaloxone group at 24 h after surgery (P < 0.05) and at 96 h after surgery (P < 0.05). Compared with those in the nonnaloxone group, the CD3 + T-cell (P < 0.05) and CD4 + T-cell (P < 0.01) counts were significantly lower in the naloxone group 24 h after surgery. At 24 h and 96 h after surgery, the WBC count (P < 0.05) and neutrophil percentage (P < 0.05) were significantly greater in the nonnaloxone group. The levels of IL-6 (P < 0.05) and calcitonin in the nonnaloxone group were significantly greater at 24 h after surgery. At 24 h following surgery, the nonnaloxone group had significantly greater levels of IL-6 (P < 0.05) and calcitonin than did the naloxone group. Compared with those in the naloxone group, the expression levels of TLR4 (P < 0.05) in gastric cancer tissue in the naloxone group were greater; however, the expression levels of IL-6 (P < 0.01) and TNF-α (P < 0.01) in the naloxone group were greater than those in the nonnaloxone group. CONCLUSION: Laparoscopic total gastrectomy patients can benefit from 0.05 ug/kg- 1. h- 1 naloxone by reducing their risk of infection. It is possible that LDN alters the number of cells in lymphocyte subpopulations, such as NK cells, CD3 + T cells, and CD4 + T cells, and the CD4+/CD8 + T-cell ratio or alters TLR4 receptor expression in immune cells, thereby altering immune cell activity. TRIAL REGISTRATION: The trial was registered at the Chinese Clinical Trial Registry on 24/11/2023 (ChiCTR2300077948).


Assuntos
Gastrectomia , Laparoscopia , Naloxona , Complicações Pós-Operatórias , Neoplasias Gástricas , Humanos , Naloxona/administração & dosagem , Gastrectomia/métodos , Masculino , Feminino , Laparoscopia/métodos , Pessoa de Meia-Idade , Neoplasias Gástricas/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Idoso , Antagonistas de Entorpecentes/administração & dosagem , Antagonistas de Entorpecentes/farmacologia , Assistência Perioperatória/métodos , Interleucina-6 , Receptor 4 Toll-Like
2.
Ecotoxicol Environ Saf ; 277: 116394, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38663197

RESUMO

Mono-2-ethylhexyl phthalic acid (MEHP) is the most toxic metabolite of the plasticizer di-2-ethylhexyl phthalic acid (DEHP), and studies have shown that MEHP causes serious reproductive effects. However, its exact mechanisms of action remain elusive. In this study, we aimed to investigate the reproductive effects of MEHP and preliminarily explore its underlying molecular mechanisms. We found that TM3 cells gradually secreted less testosterone and intracellular free cholesterol with increasing MEHP exposure. MEHP exposure inhibited lipophagy and the Sirt1/Foxo1/Rab7 signaling pathway in TM3 cells, causing aberrant accumulation of intracellular lipid droplets. Addition of the Sirt1 agonist SRT1720 and Rab7 agonist ML-098 alleviated the inhibition of lipophagy and increased free cholesterol and testosterone contents in TM3 cells. SRT1720 alleviated the inhibitory effect of MEHP on the Sirt1/Foxo1/Rab7 signaling pathway, whereas ML-098 only alleviated the inhibition of Rab7 protein expression by MEHP and had no effect on Sirt1 and Foxo1 protein expression. This suggests that MEHP inhibits lipophagy in TM3 cells by suppressing the Sirt1/Foxo1/Rab7 signaling pathway, ultimately leading to a further decrease in cellular testosterone secretion. This study improves our current understanding of the toxicity and molecular mechanisms of action of MEHP and provides new insights into the reproductive effects of phthalic acid esters.


Assuntos
Dietilexilftalato , Transdução de Sinais , Sirtuína 1 , Testosterona , proteínas de unión al GTP Rab7 , Sirtuína 1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Camundongos , Dietilexilftalato/análogos & derivados , Dietilexilftalato/toxicidade , Linhagem Celular , Proteínas rab de Ligação ao GTP/metabolismo , Proteína Forkhead Box O1/metabolismo , Plastificantes/toxicidade , Colesterol
3.
Int Wound J ; 21(4): e14547, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38098219

RESUMO

Herein, a meta-analysis was conducted to systematically evaluate the effect of humanised care on maternal postoperative wound infections in patients who underwent caesarean section. A computerised search of Embase, Cochrane Library, PubMed, Web of Science, China National Knowledge Infrastructure, Chinese Biomedical Literature Database and Wanfang database was performed, supplemented by a manual search from database inception to September 2023, to collate randomised controlled trials (RCTs) regarding the application of humanised care during the perioperative period of caesarean section. Two researchers screened and selected studies identified according to inclusion and exclusion criteria, and the included literature was evaluated for quality, extracted information and required data. Data analysis was performed using RevMan 5.4 software. Twenty RCTs comprising 2408 patients were included. The results revealed the humanised care group had a lower incidence of postoperative wound infections (0.83% vs. 4.32%, odds ratio [OR]: 0.26, 95% confidence interval [CI]: 0.15-0.46, p < 0.00001) and fewer postoperative complications than the conventional care group (4.32% vs. 16.35%, OR: 0.23, 95% CI: 0.16-0.31, p < 0.00001), with lower anxiety scores (standardised mean difference [SMD]: -3.15, 95% CI: -3.90 to -2.40, p < 0.00001) and depression scores (SMD: -3.68, 95% CI: -4.49 to -2.88, p < 0.00001). The application of humanised care during the perioperative period of caesarean section can prevent postoperative wound infection, reduce postoperative complications and help alleviate maternal anxiety and depression, which is worthy of clinical promotion and application.


Assuntos
Bandagens , Infecção da Ferida Cirúrgica , Feminino , Gravidez , Humanos , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/epidemiologia , Cesárea/efeitos adversos , China
4.
Hum Brain Mapp ; 44(16): 5450-5459, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37694907

RESUMO

Functional connectivity (FC) derived from resting-state functional magnetic resonance imaging has been widely applied to guide precise repetitive transcranial magnetic stimulation (rTMS). The left, right, and bilateral dorsolateral prefrontal cortices (DLPFC) have been used as rTMS treatment target regions for autism spectrum disorder (ASD), albeit with moderate efficacy. Thus, we aimed to develop an individualized localization method for rTMS treatment of ASD. We included 266 male ASDs and 297 male typically-developed controls (TDCs) from the Autism Brain Imaging Data Exchange Dataset. The nucleus accumbens (NAc) was regarded as a promising effective region, which was used as a seed and individualized peak FC strength in the DLPFC was compared between ASD and TDC. Correlation analysis was conducted between individualized peak FC strength and symptoms in ASD. We also investigated the spatial distribution of individualized peak FC locations in the DLPFC and conducted voxel-wise analysis to compare NAc-based FC between the two groups. ASD showed stronger peak FC in the right DLPFC related to TDC (Cohen's d = -.19, 95% CI: -0.36 to -0.03, t = -2.30, p = .02). Moreover, negative correlation was found between the peak FC strength in the right DLPFC and Autism Diagnostic Observation Schedule (ADOS) scores, which assessed both the social communication and interaction (r = -.147, p = .04, uncorrected significant), and stereotyped behaviors and restricted interests (r = -.198, p = .02, corrected significant). Peak FC locations varied substantially across participants. No significant differences in NAc-based FC in the DLPFC were found in the voxel-wise comparison. Our study supports the use of individualized peak FC-guided precise rTMS treatment of male ASD. Moreover, stimulating the right DLPFC might alleviate core symptoms of ASD.


Assuntos
Transtorno do Espectro Autista , Estimulação Magnética Transcraniana , Humanos , Masculino , Estimulação Magnética Transcraniana/métodos , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/terapia , Córtex Pré-Frontal/fisiologia , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem
5.
Ren Fail ; 45(1): 2218483, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37293809

RESUMO

Calciphylaxis is a rare cutaneous vascular disease that manifests with intolerable pains, non-healing skin wounds, histologically characterized by calcification, fibrointimal hyperplasia, and microvessel thrombosis. Currently, there are no standardized guidelines for this disease. Recent studies have recognized a high prevalence of thrombophilias and hypercoagulable conditions in calciphylaxis patients. Here, we report a case of uremic calciphylaxis patient whom was refractory to conventional treatments and then received a salvage strategy with intravenous and local hAMSC application. In order to investigate the therapeutic mechanism of hAMSCs from the novel perspective of hypercoagulability, coagulation-related indicators, wound status, quality of life and skin biopsy were followed up. Polymerase chain reaction (PCR) was performed to determine the distribution of hAMSCs in multiple tissues including lung, kidney and muscle after infusion of hAMSCs for 24 h, 1 week and 1 month in mice aiming to investigate whether hAMSCs retain locally active roles after intravenous administration. Improvement of hypercoagulable condition involving correction of platelet, D-dimer and plasminogen levels, skin regeneration and pain alleviation were revealed after hAMSC administration over one-year period. Skin biopsy pathology suggested regenerative tissues after 1 month hAMSC application and full epidermal regeneration after 20 months hAMSC treatment. PCR analysis indicated that hAMSCs were homing in lung, kidney and muscle tissues of mice even until tail vein injection of hAMSCs for 1 month. We propose that hypercoagulability is a promising therapeutic target of calciphylaxis patients, which can be effectively improved by hAMSC treatment.


Assuntos
Calciofilaxia , Células-Tronco Mesenquimais , Trombofilia , Humanos , Camundongos , Animais , Âmnio , Calciofilaxia/etiologia , Calciofilaxia/terapia , Qualidade de Vida , Trombofilia/etiologia
6.
Int Wound J ; 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853846

RESUMO

We conducted a meta-analysis to assess the effects of bundle-care interventions on pressure ulcers in patients with stroke to provide a basis for clinical work. Randomised controlled trials on the effects of bundle-care interventions in patients with stroke were identified using computerised searches of the PubMed, Embase, Cochrane Library, Chinese National Knowledge Infrastructure, VIP and Wanfang databases, from the time of inception of each database to July 2023, supplemented by manual literature searches. Two researchers independently retrieved and screened the articles, extracted the data and evaluated the quality of the included studies. After reaching consensus, meta-analysis was performed using RevMan 5.4. Twenty-four papers were included, involving 3330 patients of whom 1679 were in the intervention group and 1651 were in the control group. The results showed that, compared with standard care, bundle-care interventions significantly reduced the incidence of pressure ulcers (3.28% vs. 14.84%, odds ratio [OR]: 0.19, 95% confidence interval [CI]: 0.14-0.26, p < 0.001), and aspiration (5.60% vs. 18.84%, OR: 0.25, 95% CI: 0.17-0.39, p < 0.001), and improved patient satisfaction with nursing care (96.59% vs. 84.43%, OR. 5.45, 95% CI: 3.76-7.90, p < 0.001). Current evidence suggests that care bundles are significantly better than conventional nursing measures in preventing pressure ulcers and aspiration, and improving patient satisfaction with nursing care in patients with stroke, and are worthy of clinical promotion and application.

7.
Planta ; 256(3): 56, 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35932402

RESUMO

MAIN CONCLUSION: VvTOR interacts with VvSnRK1.1 and regulates sugar accumulation and sugar-related genes expression in grape. Target of rapamycin (TOR) and sucrose-non-fermenting-related protein kinase 1.1 (SnRK1.1) both are critical proteins in plant sugar metabolism. Glucose-TOR signaling dictates transcriptional reprogramming of gene sets involved in central and secondary metabolism, cell cycle, transcription, signaling, transport and folding. SnRK1.1 is involved in sucrose-induced hypocotyl elongation. However, the relationship of TOR and SnRK1.1 in regulating sugar metabolism is unclear. In the study, we utilized grape (Vitis vinifera) calli to explore the relationship between TOR and SnRK1.1 in the sugar metabolism. We found that VvTOR interacted with VvSnRK1.1. By subcellular localization, VvTOR was found in the nucleus and cell membrane. Transgenic grape calli achieved by Agrobacterium-mediated transformation contained less glucose compared to WT calli. The fructose contents were markedly increased in the overexpressing VvTOR (OE-VvTOR), OE-VvTOR + RNAi-VvSnRK1.1 and RNAi-VvTOR + OE-VvSnRK1.1 transgenic calli. Sucrose contents were significantly increased in the OE-VvTOR transgenic calli and reduced in the OE-VvTOR + RNAi-VvSnRK1.1 transgenic calli, which implied that the pathway of VvTOR improving sucrose content might need the expression of VvSnRK1.1. VvTOR interacted with VvSnRK1.1 and regulated sugar metabolism in grape. These results suggest that there is a crosstalk between TOR and SnRK1.1 in plant sugar metabolism.


Assuntos
Vitis , Regulação da Expressão Gênica de Plantas , Glucose/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sacarose/metabolismo , Açúcares/metabolismo , Vitis/genética , Vitis/metabolismo
8.
Mikrochim Acta ; 189(12): 456, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36416994

RESUMO

In order to improve the selectivity and stability of melamine-formaldehyde (MF) aerogel, it was composited with TiO2 aerogel. A TiO2-MF hybrid aerogel was in situ prepared on the surface of carbon fibers for in-tube solid-phase microextraction (SPME). The extraction performance of TiO2-MF aerogel was regulated by changing the ratio of TiO2 sol and MF sol during the material preparation. Coupled with high-performance liquid chromatography-diode array detection (HPLC-DAD), the extraction tube filled by TiO2-MF aerogel-coated carbon fibers was evaluated with several types of environmental pollutants including polycyclic aromatic hydrocarbons (PAHs), estrogens, and ultraviolet filters. Because of favourable extraction performance of PAHs they were selected as model analytes, and some important influence factors were optimized for satisfactory sensitivity. The detection limits were in the range 0.05-0.10 µg L-1, owing to high enrichment factors (653-1007). The online in-tube SPME-HPLC-DAD method was verified for the determination of trace PAHs in environmental water samples, and acceptable recovery (70-118%) was achieved. The analytical methods also displayed some advantages in comparison with other reports. Moreover, the extraction tube exhibited satisfactory chemical stability.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Microextração em Fase Sólida , Cromatografia Líquida de Alta Pressão , Fibra de Carbono , Formaldeído
9.
Biochem Biophys Res Commun ; 554: 193-198, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-33798947

RESUMO

WRKY transcription factors are one of the largest transcriptional regulator families, involved in various signaling networks in plants. However, only limited functional exploration of the sugar signaling of Vitis vinifera WRKY22 transcription factor (VvWRKY22) has been conducted. In this study, the roles played by VvWRKY22 in sugar accumulation in grapes were investigated. VvWRKY22 was co-expressed with 16 sugar-related genes, and the expression of VvWRKY22 in grape suspension cells was inhibited by sucrose, and induced by fructose and abscisic acid (ABA). Results showed that over-expression of VvWRKY22 decreased the sucrose, glucose and fructose content, and regulated the expression levels of sugar and ABA-related genes. Moreover, it was found that VvWRKY22 interacted with VvSnRK1.1 or VvSnRK1.2 proteins (Sucrose non-fermenting-1-related protein kinase 1), which are important kinases related to sugar metabolism. These results, thus, provide new genetic evidences to support the view that VvWRKY22 functions in regulating sugar metabolism in grapes.


Assuntos
Frutose/metabolismo , Glucose/metabolismo , Proteínas de Plantas/metabolismo , Sacarose/metabolismo , Fatores de Transcrição/metabolismo , Vitis/metabolismo , Ácido Abscísico/metabolismo , Sequência de Aminoácidos , Filogenia , Proteínas de Plantas/genética , Homologia de Sequência , Transdução de Sinais , Fatores de Transcrição/genética , Vitis/genética , Vitis/crescimento & desenvolvimento
10.
Ophthalmology ; 127(1): 27-37, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31543351

RESUMO

PURPOSE: To compare wear of standard, adjustable, and ready-made glasses among children. DESIGN: Randomized, controlled, open-label, noninferiority trial. PARTICIPANTS: Students aged 11 to 16 years with presenting visual acuity (VA) ≤6/12 in both eyes, correctable to ≥6/7.5, subjective spherical equivalent refractive error (SER) ≤-1.0 diopters (D), astigmatism and anisometropia both <2.00 D, and no other ocular abnormalities. METHODS: Participants were randomly allocated (1:1:1) to standard glasses, ready-made glasses, or adjustable glasses based on self-refraction. We recorded glasses wear on twice-weekly covert evaluation by head teachers (primary outcome), self-reported and investigator-observed wear, best-corrected visual acuity (BCVA) (not prespecified), children's satisfaction, and value attributed to glasses. MAIN OUTCOME MEASURE: Proportion of glasses wear on twice-weekly covert evaluation by head teachers over 2 months. RESULTS: Among 379 eligible participants, 127 were allocated to standard glasses (mean age, 13.7 years; standard deviation [SD], 1.0 years; 54.3% were male), 125 to ready-made (mean age, 13.6; SD, 0.83; 45.6%), and 127 to adjustable (mean age, 13.4 years; SD, 0.85; 54.3%). Mean wear proportion of adjustable glasses was significantly lower than for standard glasses (45% vs. 58%; P = 0.01), although the adjusted difference (90% confidence interval [CI], -19.0% to -3.0%) did not meet the prespecified inferiority threshold of 20%. Self-reported (90.2% vs. 84.8%, P = 0.64) and investigator-observed (44.1% vs. 33.9%, P = 0.89) wear did not differ between standard and adjustable glasses, nor did satisfaction with (P = 0.97) or value attributed to study glasses (P = 0.55) or increase in quality of life (5.53 [SD, 4.47] vs. 5.68 [SD, 4.34] on a 100-point scale, P > 0.30). Best-corrected visual acuity with adjustable glasses was better (P < 0.001) than with standard glasses. Change in power of study lenses at the end of the study (adjustable: 0.65 D, 95% CI, 0.52-0.79; standard, 0.01 D; 95% CI, -0.006 to 0.03, P < 0.001) was greater for adjustable glasses, although interobserver variation in power measurements may explain this. Lens scratches and frame damage were more common with adjustable glasses, whereas lens breakage was less common than for standard glasses. CONCLUSIONS: Proportion of wear was lower with adjustable glasses, although VA was better and measures of satisfaction and quality of life were not inferior to standard glasses.


Assuntos
Óculos , Manufaturas , Refração Ocular/fisiologia , Erros de Refração/terapia , Transtornos da Visão/terapia , Adolescente , Povo Asiático/etnologia , Criança , China/epidemiologia , Feminino , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Cooperação do Paciente , Satisfação do Paciente , Desenho de Prótese , Erros de Refração/etnologia , Erros de Refração/fisiopatologia , Inquéritos e Questionários , Transtornos da Visão/etnologia , Transtornos da Visão/fisiopatologia , Seleção Visual , Acuidade Visual/fisiologia
11.
Cancer Cell Int ; 19: 339, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31889892

RESUMO

BACKGROUND: Ovarian cancer is one of the leading causes of female death worldwide, with a poor prognosis of advanced patients. Sevoflurane, a volatile anesthetic commonly used in clinical operations, has been reported to have anti-cancer activity against some tumors. In the present study, we aimed to investigate the effects of sevoflurane on the progression of ovarian cancer and its potential mechanism. METHODS: The effects of sevoflurane on ovarian cancer cell viability, proliferation, migration, invasion, cell cycle, and apoptosis were determined by functional experiments in vitro. Gelatin zymography assay was performed to examine MMP9 activity. In vivo, sevoflurane was injected into mice of transplantation tumor with SKOV3 cells or with pcDNA-STC1 treated SKOV3 cells. RESULTS: We found that sevoflurane inhibited the viability of SKOV3 and OVCAR3 cells in a dose-dependent manner, and colony formation assay revealed that sevoflurane inhibited ovarian cancer cell colony-formation abilities. Additionally, sevoflurane could induce cell cycle arrest and promote cell apoptosis in SKOV3 and OVCAR3 cells. Moreover, sevoflurane reduced the migration and invasion abilities of SKOV3 and OVCAR3 cells, as well as the MMP-9 activity. Furthermore, sevoflurane down-regulated the expression of stanniocalcin 1 (STC1), and up-regulation of STC1 could reverse the inhibitory effects of sevoflurane on cell proliferation and invasion. In vivo, sevoflurane significantly inhibited the tumor growth, which was be reversed by STC1 overexpression. CONCLUSION: These data reveal an anti-cancer activity of sevoflurane on the growth and invasion of ovarian cancer, which may be through down-regulating STC1. Sevoflurane may serve as a potential anti-cancer agent in ovarian cancer therapy.

12.
J Sep Sci ; 42(12): 2163-2170, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30997952

RESUMO

Polydopamine was coated onto cotton fibers as the adsorbent to improve the extraction efficiency. Polydopamine-coated cotton fibers were placed into a polyetheretherketone tube for in-tube solid-phase microextraction. To develop an online analysis system, the extraction tube was connected with high-performance liquid chromatography. The tube was evaluated with five estrogenic analytes, and the extraction and desorption conditions were optimized to get high extraction efficiency. Under the optimum conditions, the enrichment factors of five analytes were 143-1745. An online analysis method was established, it had large linear ranges (0.10-40 and 0.16-40 µg/L), low limits of detection (0.03, 0.05 µg/L) and satisfactory repeatability (≤3.2%). The analysis method was applied to detect targets in the real samples like as hot water in new plastic cup and tap water. The relative recoveries spiked at 1 and 5 µg/L in these samples were investigated and the results were in the range of 83.7-109%.


Assuntos
Fibra de Algodão , Indóis/química , Polímeros/química , Microextração em Fase Sólida , Poluentes Químicos da Água/análise , Adsorção
13.
J Sep Sci ; 42(14): 2398-2406, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31038258

RESUMO

Polypropylene hollow fibers as the adsorbent were directly filled into a polyetheretherketone tube for in-tube solid-phase microextraction. The surface properties of hollow fibers were characterized by a scanning electron microscope. Combined with high performance liquid chromatography, the extraction tube showed good extraction performance for five environmental estrogen hormones. To achieve high analytical sensitivity, four important factors containing sampling volume, sampling rate, content of organic solvent in sample, and desorption time were investigated. Under the optimum conditions, an online analysis method was established with wide linear range (0.03-20 µg/L), good correlation coefficients (≥0.9998), low limits of detection (0.01-0.05 µg/L), low limits of quantitation (0.03-0.16 µg/L), and high enrichment factors (1087-2738). Relative standard deviations (n = 3) for intraday (≤3.6%) and interday (≤5.1%) tests proved the stable extraction performance of the material. Durability and chemical stability of the extraction tube were also investigated, relative standard deviations of all analytes were less than 5.8% (n = 3), demonstrating the satisfactory stability. Finally, the method was successfully applied to detect estrogens in real samples.


Assuntos
Estrogênios/análise , Polipropilenos/química , Microextração em Fase Sólida , Poluentes Químicos da Água/análise , Tamanho da Partícula , Propriedades de Superfície
14.
J Sep Sci ; 42(21): 3363-3371, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31486232

RESUMO

Nano-molybdenum trioxide was prepared from nano-molybdenum disulfide by simple firing in muffle furnace. Nano-molybdenum trioxide was used as the extraction coating on the stainless steel wire. Four wires were filled in a polyetheretherketone tube to get an extraction tube. The tube was connected to the six-port valve of a high performance liquid chromatograph, and the online analysis system was constructed. Extraction selectivity of the tube for different types of compounds, including polycyclic aromatic hydrocarbons, plasticizers, estrogens, anilines and neonicotinoids, was studied. Good enrichment ability for polycyclic aromatic hydrocarbons, but the extraction efficiency of others was not satisfactory. Using eight polycyclic aromatic hydrocarbons as the targets, an analytical method was established after optimizing main factors such as sampling volume, sampling rate, methanol content, and desorption time. The established method exhibited wide linear range to 0.016-20.00 µg/L and low limits of detection to 0.005 µg/L, and the enrichment factors can be up to 2443. The method was applied to the detection of trace polycyclic aromatic hydrocarbons in tap water and river water, and a good recovery was obtained. The tube showed good durability and chemical stability, and it still remained good extraction effect after more than 140 run.

15.
J Sep Sci ; 42(5): 1051-1057, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30659743

RESUMO

Natural cotton fiber was applied as a green extraction material for in-tube solid-phase microextraction. Cotton fibers were characterized by scanning electron microscope. A bundle of cotton fibers (685 mg, 20 cm) was directly packed into a polyetheretherketone tube (i.d. 0.75 mm) to get the extraction device. It was connected into high performance liquid chromatography, building an online extraction and dectection system. Through the online analysis system, several polycyclic aromatic hydrocarbons were used as the targets to evaluate the extraction performace of the device. In order to get high extraction efficiency and sensitivity, the extraction and desorption conditions were optimized. Under the optimum conditions, the sensitive analysis method was established, and provided low limits of detection of 0.02 and 0.05 µg/L, good linearity ranges of 0.06-15 and 0.16-15 µg/L, as well as high enrichment factors of 176-1868. The method was applied to the online determination of trace polycyclic aromatic hydrocarbons in snow water and river water, and the relative recoveries corresponding to 2 and 5 µg/L were in the range of 80-116%. The repeatability of extraction and preparation of the device was investigated and the relative standard deviations (n = 3) were less than 3.6 and 5.2%.


Assuntos
Produtos Biológicos/isolamento & purificação , Fibra de Algodão/análise , Microextração em Fase Sólida , Benzofenonas , Produtos Biológicos/química , Cetonas/química , Microscopia Eletrônica de Varredura/instrumentação , Polietilenoglicóis/química , Polímeros , Microextração em Fase Sólida/instrumentação
16.
J Sep Sci ; 42(12): 2155-2162, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30993880

RESUMO

Cotton fiber is an environmentally friendly and natural material with a certain extraction capacity, while its enrichment ability is poor. In order to improve the extraction efficiency of cotton fibers, it was carbonized to form a layer of amorphous carbon as the sorbent by a simple carbonization method. Carbonized cotton fibers were filled into a polyetheretherketone tube for in-tube solid-phase microextraction. The carbonization time was investigated to obtain high extraction efficiency. Coupled to high-performance liquid chromatography, the extraction tube was evaluated with polycyclic aromatic hydrocarbons, estrogens and phthalates, and it exhibited best extraction efficiency for polycyclic aromatic hydrocarbons. Under the optimum conditions, an online analysis method for several polycyclic aromatic hydrocarbons was established with large linear ranges (0.016-0.20 µg/L), low limits of detection (0.005-0.020 µg/L), and high enrichment factors (948-2874). Analysis method was successfully applied to the detection of targets in the real samples and shown satisfactory durability and chemical stability. Moreover, the relative recoveries ranged from 82 to 119.2%, which demonstrated the applicability of carbonized cotton fibers in sample preparation. Compared with other reported methods, the proposed method provided shorter extraction time, higher enrichment factors, comparable limits of detection, and recoveries.

17.
Clin Exp Ophthalmol ; 47(7): 909-917, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31090978

RESUMO

IMPORTANCE: Presbyopia, an essentially universal, age-related loss of the ability to focus un-aided on near objects, is the world's leading cause of visual impairment. BACKGROUND: Smartphone use is widespread in China, but little is known about the prevalence, determinants and correction of difficulties with smartphone use in the setting of presbyopia. DESIGN: Cross-sectional data from a population-based longitudinal cohort study. PARTICIPANTS: A total of 1817 persons aged ≥35 years in Guangzhou, Southern China. METHODS: Participants underwent near visual acuity (NVA) testing and completed questionnaires on smartphone usage detailing knowledge of their own presbyopia status, frequency (hours/day) and subjective difficulties with use of mobile and smartphones. Presbyopia was defined as uncorrected bilateral NVA ≤6/12 with best-corrected bilateral NVA >6/12. MAIN OUTCOME MEASURES: Difficulty in smartphone use associated with uncorrected presbyopia. RESULTS: Among 1427 respondents (78.5%) undergoing examination, 1191 (83.5%) completed questionnaires (mean age 52.3 ± 11.6 years; 54.9% women). Among 451 persons (37.8%) with presbyopia owning smartphones, 290 (64.3%) reported difficulty using them. Multiple ordinal logistic regression modelling showed difficulty in smartphone use due to presbyopia was associated with higher educational level (P = .013), worse NVA (P < .001) and more time spent using smartphones (P = .002 for 1-3 hours/day). Among persons with presbyopia owning smartphones, 353 (78.0%) said they would pay >US$15 (median US$45) for innovations making smartphone use easier. CONCLUSIONS AND RELEVANCE: Difficulty in using smartphones in the presence of presbyopia is common and affected persons are willing to pay for useful solutions to the problem.


Assuntos
Povo Asiático/estatística & dados numéricos , Presbiopia/epidemiologia , Smartphone/estatística & dados numéricos , Transtornos da Visão/epidemiologia , Adulto , Idoso , China/epidemiologia , Estudos Transversais , Óculos/estatística & dados numéricos , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Inquéritos e Questionários , Acuidade Visual
18.
Clin Exp Ophthalmol ; 47(2): 179-186, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30117241

RESUMO

IMPORTANCE: Uncorrected refractive error causes 90% of poor vision among Chinese children. BACKGROUND: Little is known about teachers' influence on children's glasses wear. DESIGN: Cohort study. PARTICIPANTS: Children at 138 randomly selected primary schools in Guangdong and Yunnan provinces, China, with uncorrected visual acuity (VA) ≤6/12 in either eye correctable to >6/12 in both eyes, and their teachers. METHODS: Teachers and children underwent VA testing and completed questionnaires about spectacles use and attitudes towards children's vision. MAIN OUTCOME MEASURES: Children's acceptance of free glasses, spectacle purchase and wear. RESULTS: A total of 882 children (mean age 10.6 years, 45.5% boys) and 276 teachers (mean age 37.9 years, 67.8% female) participated. Among teachers, 20.4% (56/275) believed glasses worsened children's vision, 68.4% (188/275) felt eye exercises prevented myopia, 55.0% (151/275) thought children with modest myopia should not wear glasses and 93.1% (256/275) encouraged children to obtain glasses. Teacher factors associated with children's glasses-related behaviour included believing glasses harm children's vision (decreased purchase, univariate model: relative risk [RR] 0.65, 95% CI 0.43, 0.98, P < 0.05); supporting children's classroom glasses wear (increased glasses wear, univariate model: RR 2.20, 95% CI 1.23, 3.95, P < 0.01); and advising children to obtain glasses (increased free glasses acceptance, multivariate model: RR 2.74, 95% CI 1.29, 5.84, P < 0.01; increased wear, univariate model: RR 2.93, 95% CI 1.45, 5.90, P < 0.01), but not teacher's ownership/wear of glasses. CONCLUSIONS AND RELEVANCE: Though teachers had limited knowledge about children's vision, they influenced children's glasses acceptance.


Assuntos
Óculos/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Erros de Refração/terapia , População Rural/estatística & dados numéricos , Professores Escolares/psicologia , Estudantes/psicologia , Adulto , Atitude Frente a Saúde , Criança , China/epidemiologia , Estudos de Coortes , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Refração Ocular/fisiologia , Inquéritos e Questionários , Testes Visuais , Acuidade Visual/fisiologia
19.
Mikrochim Acta ; 186(12): 769, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713699

RESUMO

A combination between an ionic liquid and melamine-formaldehyde aerogel on the carbon fibers was developed for in-tube solid-phase microextraction of estrogens with high efficiency. The sorbent has a high enrichment capability for several estrogens. Scanning electron microscopy showed that the aerogel on the carbon fibers has a porous three-dimensional network structure. Several important parameters such as sampling volume, sampling rate, the concentration of organic solvent in sample, pH value of sample as well as desorption time were optimized towards estrogen targets. Comparing with melamine-formaldehyde aerogel coating, the coating gave higher extraction efficiency. Comparing with melamine-formaldehyde aerogel coating, the new coating displays higher extraction efficiency. An online analytical method of estrogens was established, by the combination between in-tube solid-phase microextraction and high performance liquid chromatography with diode array detector. Analytical figures of merit include low limits of detection (<0.20 µg L-1), wide linearity (0.15-20 µg L-1), high enrichment factors (1028-1256), good extraction repeatability (RSDs<2.5%) and satisfactory preparation repeatability (RSDs<10.5%). The method was applied to the determination of trace estrogen targets in plastic bottle, tap water and surface water. Graphical abstractSchematic representation of online combination between in-tube solid-phase microextraction and high performance liquid chromatography, based on an ionic liquid (IL)-modified melamine-formaldehyde (MF) aerogel coating on carbon fibers (CFs) in a polyether-etherketone (PEEK) tube.


Assuntos
Estrogênios/análise , Líquidos Iônicos/química , Microextração em Fase Sólida , Triazinas/química , Cromatografia Líquida de Alta Pressão , Géis/química , Tamanho da Partícula , Propriedades de Superfície
20.
J Sep Sci ; 41(9): 1995-2002, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29377595

RESUMO

Silicon carbide has excellent properties, such as corrosion resistance, high strength, oxidation resistance, high temperature, and so on. Based on these properties, silicon carbide was coated on stainless-steel wire and used as a solid-phase microextraction coating, and polycyclic aromatic hydrocarbons were employed as model analytes. Using gas chromatography, some important factors that affect the extraction efficiency were optimized one by one, and an analytical method was established. The analytical method showed wide linear ranges (0.1-30, 0.03-30, and 0.01-30 µg/L) with satisfactory correlation coefficients (0.9922-0.9966) and low detection limits (0.003-0.03 µg/L). To investigate the practical application of the method, rainwater and cigarette ash aqueous solution were collected as real samples for extraction and detection. The results indicate that silicon carbide has excellent application in the field of solid-phase microextraction.

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