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1.
Anal Methods ; 15(9): 1206-1214, 2023 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-36807579

RESUMEN

Steroid hormones have been listed as priority pollutants in the environment, and their detection and pollution control deserve our extensive attention. In this study, a modified silica gel adsorbent material was synthesized by benzoyl isothiocyanate reaction with hydroxyl groups on the silica gel surface. The modified silica gel was used as a solid phase extraction filler for the extraction of steroid hormones from water, which was further analyzed by the HPLC-MS/MS method. The FT-IR, TGA, XPS, and SEM analysis indicated that benzoyl isothiocyanate was successfully grafted on the surface of silica gel to form a bond with an isothioamide group and benzene ring as the tail chain. The modified silica gel synthesized at 40 °C showed excellent adsorption and recovery rates for three steroid hormones in water. Methanol at pH 9.0 was selected as the optimal eluent. The adsorption capacity of the modified silica gel for epiandrosterone, progesterone, and megestrol acetate was 6822 ng mg-1, 13 899 ng mg-1, and 14 301 ng mg-1, respectively. Under optimal conditions, the limit of detection (LOD) and limit of quantification (LOQ) for 3 steroid hormones by modified silica gel extraction with HPLC-MS/MS detection were 0.02-0.88 µg L-1 and 0.06-2.22 µg L-1, respectively. The recovery rate of epiandrosterone, progesterone, and megestrol was between 53.7% and 82.9%, respectively. The modified silica gel has been successfully used to analyze steroid hormones in wastewater and surface water.


Asunto(s)
Espectrometría de Masas en Tándem , Agua , Gel de Sílice/química , Progesterona , Espectroscopía Infrarroja por Transformada de Fourier , Androsterona , Esteroides , Isotiocianatos
2.
Heliyon ; 9(2): e13090, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36713626

RESUMEN

Objective: During the coronavirus disease 2019 (COVID-19) pandemic, an increased mental burden has been widely reported among medical health workers such as physicians and nurses. However, data on laboratory technicians exposed to COVID-19 have rarely been published. The aim of this study was to assess the magnitude of psychological symptoms among laboratory technicians and analyze potential risk factors associated with these symptoms. Methods: A cross-sectional online survey was performed via the Wenjuanxing platform (a professional online questionnaire platform) (https://www.wjx.cn/mobile/statnew.aspx) to investigate the mental health of laboratory technicians during the COVID-19 pandemic in Hebei, China from October 4, 2021, to November 3, 2021. The online questionnaire included demographic and occupational characteristics data of responders, and the Symptom Check List-90-Revised (SCL90-R)was used to quantify the magnitude of psychological symptoms among laboratory technicians. Participants' demographic and occupational characteristics were analyzed using descriptive statistical analyses. Chi-square tests were applied to compare the severity of each symptom between two or more groups. A binary logistic regression model was developed to identify the predictors of laboratory technicians' mental health in response to the COVID-19 pandemic, and outcomes are presented as odds ratios and 95% confidence interval. Statistical analysis was performed using SPSS version 21 (SPSS, New Orchard Road, Armonk, New York, USA). Results: A total of 3081 valid questionnaires were collected. Of these 3081 participants, 338 (11.0%) reported a total SCL90-R score >160, which indicated positive psychological symptoms. Among the 338 participants who reported psychological problems, most of them were mild symptoms. Several factors associated with mental health problems in laboratory technicians during COVID-19 were found, which include a history of physical and/or psychological problems (all 10 symptoms p < 0.001), more than 10 years of work experience (depression symptoms: OR = 2.350, p = 0.024; anxiety symptoms: OR = 2.642, p = 0.038), frontline work (depression symptoms: OR = 1.761, p = 0.001; anxiety symptoms: OR = 2.619, p < 0.001; hostility symptoms: OR = 1.913, p = 0.001), participant in more than 3 times large-scale SARS-CoV-2 screenings and more than 36 h per week in SARS-CoV-2 nucleic acid testing. Conclusion: A portion of laboratory technicians reported experiencing varying levels of psychological burden. During the COVID-19 pandemic, multiple interventions should be developed and implemented to address existing psychosocial challenges and promote the mental health of laboratory technicians.

3.
IBRO Neurosci Rep ; 15: 107-115, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38204574

RESUMEN

Motions sickness (MS) occurs when the brain receives conflicting sensory signals from vestibular, visual and proprioceptive systems about a person's ongoing position and/or motion in relation to space. MS is typified by symptoms such as nausea and emesis and implicates complex physiological aspects of sensations and sensorimotor reflexes. Use of animal models has been integral to unraveling the physiological causality of MS. The commonly used rodents (rat and mouse), albeit lacking vomiting reflex, reliably display phenotypic behaviors of pica (eating of non-nutritive substance) and conditioned taste aversion (CTAver) or avoidance (CTAvoi) which utilize neural substrates with pathways that cause gastrointestinal malaise akin to nausea/emesis. As such, rodent pica and CTAver/CTAvoi have been widely used as proxies for nausea/emesis in studies dealing with neural mechanisms of nausea/emesis and MS, as well as for evaluating therapeutics. This review presents the rationale and experimental evidence that support the use of pica and CTAver/CTAvoi as indices for nausea and emesis. Key experimental steps and cautions required when using rodent MS models are also discussed. Finally, future directions are suggested for studying MS with rodent pica and CTAver/CTAvoi models.

4.
ACS Nano ; 16(8): 12174-12184, 2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-35900818

RESUMEN

Two-dimensional (2D) semiconductors for photocatalysis are more advantageous than the other photocatalytic materials since the 2D semiconductors generally have large specific surface area and abundant active sites. Phosphorus silicon (SiP), with an indirect bandgap in bulk and a direct bandgap in the monolayer, has recently emerged as an attractive 2D material because of its anisotropic layered structure, tunable bandgap, and high charge carrier mobility. However, the utilization of SiP as a photocatalyst for photocatalysis has been scarcely studied experimentally. Herein, we reported the synthesis of SiP nanosheets (SiP NSs) prepared from bulk SiP by an ultrasound-assisted liquid-phase exfoliation approach which can act as a metal-free, efficient, and visible-light-responsive photocatalyst for photocatalytic H2 production and nitrogen fixation. In a half-reaction system, the maximal H2 and NH3 generation rate under visible light irradiation achieves 528 and 35 µmol·h-1·g-1, respectively. Additionally, the apparent quantum yield for H2 production at 420 nm reaches 3.56%. Furthermore, a Z-scheme photocatalytic overall water-splitting system was successfully constructed by using Pt-loaded SiP NSs as the H2-evolving photocatalyst, Co3O4/BiVO4 as the O2-evolving photocatalyst, and Co(bpy)33+/2+ as an electron mediator. Notably, the highest H2 and O2 generation rate with respect to Pt/SiP NSs achieves 71 and 31 µmol·h-1·g-1, respectively. This study explores the potential application of 2D SiP as a metal-free visible-light-responsive photocatalyst for photocatalysis.

5.
Micromachines (Basel) ; 13(5)2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35630207

RESUMEN

Microbubbles have important applications in optofluidics. The generation and growth of microbubbles is a complicated process in microfluidic channels. In this paper, we use a laser to irradiate light-absorbing particles to generate microbubbles in capillary tubes and investigate the factors affecting microbubble size. The results show that the key factor is the total area of the light-absorbing particles gathered at the microbubble bottom. The larger the area of the particles at bottom, the larger the size of the microbubbles. Furthermore, the area is related to capillary tube diameter. The larger the diameter of the capillary tube, the more particles gathered at the bottom of the microbubbles. Numerical simulations show that the Marangoni convection is stronger in a capillary tube with a larger diameter, which can gather more particles than that in a capillary tube with a smaller diameter. The calculations show that the particles in contact with the microbubbles will be in a stable position due to the surface tension force.

6.
Rev Sci Instrum ; 92(11): 114902, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34852507

RESUMEN

The photothermal effects have shown the possibilities for applications in optical manipulation. In this paper, an approach is demonstrated to generate and manipulate a bubble using the photothermal effects. First, a high-power laser is used to irradiate the light absorbing particles for creating a microbubble. The bubble grows up to a diameter of a few hundred micrometers in several seconds due to the diffusion of dissolved gases. The bubble does not float up and is confined at the lower boundary of the sample cell by the thermocapillary force. The force is induced by laser heating of the particles at the bubble base. Second, the bubble can be manipulated following the laser focal spot. The bubble is dragged by the horizontal component of thermocapillary force. The bubble re-grows as it moves because it absorbs the dissolved gases in its migration path. The bubble floats up finally when it grows up to the maximum size. The perpendicular component of thermocapillary force can be estimated equal to the buoyancy of the floated bubble and is about 38 nN at the laser power of 130 mW. Furthermore, we show the generation and manipulation of the bubbles in a capillary. The reason for the decrease in movement velocity in the capillaries has been studied and discussed. The approach of bubble manipulation shows a potential application in transporting the microparticles.

7.
Chem Commun (Camb) ; 57(77): 9898-9901, 2021 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-34494624

RESUMEN

A Z-scheme system was successfully constructed for visible-light-driven photocatalytic H2 production from lignocelluloses, the highest H2 evolution rate of this Z-scheme system is 5.3 and 1.6 µmol h-1 in α-cellulose and poplar wood chip aqueous solutions, respectively, under visible light irradiation.

8.
Shanghai Kou Qiang Yi Xue ; 30(6): 561-566, 2021 Dec.
Artículo en Chino | MEDLINE | ID: mdl-35587007

RESUMEN

PURPOSE: To explore pro-angiogenic miRNAs differentially expressed in dental tissue-derived stem cells under hypoxia. METHODS: Stem cells from apical papilla, dental pulp stem cells and periodontal ligament stem cells were obtained from 3 patients, and treated with nomoxia or hypoxia for 1, 3, 5 d, respectively. Real-time PCR was performed to evaluate the expression of 9 specifically identified pro-angiogenic miRNAs and HIF-1α. SPSS 19.0 software package was used for statistical analysis. RESULTS: At the fifth day of hypoxic condition, as for SCAPs, the expression of miR-126 was relatively increased while miR-20a, miR-20b, miR-21, miR-130a, miR-132, miR-210 and miR-503 deceased. As for DPSCs, the expression of miR-21, miR-130a, miR-126 and miR-210 were relatively increased while miR-132 decreased. As for PDLSCs, the expression of miR-126, miR-21 and miR-296 were relatively increased. Finally, the expression of HIF-1α was relatively upregulated in all three type of cells. CONCLUSIONS: Pro-angiogenic miRNAs in dental tissue-derived stem cells under hypoxia exists specific expression profile.


Asunto(s)
Pulpa Dental , MicroARNs , Hipoxia de la Célula , Células Cultivadas , Pulpa Dental/metabolismo , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Ligamento Periodontal , Reacción en Cadena en Tiempo Real de la Polimerasa , Células Madre/metabolismo
9.
Arch Biochem Biophys ; 663: 269-275, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30677405

RESUMEN

Gastric cancer is the second most leading cause of cancer related mortality across the world over. Although the incidence of GC has declined to some extent but it is still the fourth highly diagnosed cancer across the world. GC generally remains undiagnosed till advanced stages due to unavailability of biomarkers and when diagnosed it becomes difficult to manage due to the lack of therapeutic targets and efficient chemotherapy. There are concrete evidences suggesting that miRNAs may prove important therapeutic targets for the treatment of devastating diseases such as cancer. The study was designed to investigate the tumor suppressive role of miR-31 via regulation of zeste homolog 2 (ZH2). It was found that miR-31 is significantly downregulated in GC cell lines. Overexpression of miR-31 causes significant (P < 0.05) decrease in the viability and colony formation via initiation of G2/M cell cycle arrest of the AGS cancer cells. Moreover, miR-31 overexpression also enhanced the chemosensitivity of miR-31 to the anticancer drug 5-fluorouracil. In silico analysis together with dual luciferase reporter assay indicated zeste homolog 2 (ZH2) to be the potential target of miR-31 in AGS cells. Investigation of ZH2 expression in GC cell lines showed it to be significantly (P < 0.05) upregulated. Nonetheless, overexpression of miR-31 in AGS cells resulted in the suppression of ZH2 expression. Additionally, silencing of ZH2 in the AGS cells also caused inhibition of AGS cell proliferation and colony formation via G2/M arrest. Moreover, overexpression of ZH2 could at least partially reverse the tumor suppressive effects of miR-31 indicating direct involvement of ZH2 in the miR-31 mediated inhibitory effects on AGS cell proliferation. Finally, miR-31 overexpression caused significant (P < 0.05) inhibition of the migration and invasion of the AGS gastric cancer cells. The overexpression of miR-31 also caused downregulation of mesenchymal markers (Vimentin and N-cadherin) and upregulation of epithelial marker (E-cadherin) protein expression was in AGS cells. It is therefore concluded that miR-31 acts as a tumor suppressor and may prove essential in the treatment of GC.


Asunto(s)
División Celular/genética , Proteína Potenciadora del Homólogo Zeste 2/genética , Fase G2/genética , MicroARNs/fisiología , Invasividad Neoplásica/genética , Metástasis de la Neoplasia/genética , Neoplasias Gástricas/patología , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/genética , Regulación hacia Abajo/genética , Humanos
10.
Chin Med J (Engl) ; 131(9): 1030-1033, 2018 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-29692372

RESUMEN

BACKGROUND: Asthma is a common chronic respiratory disease and is related to air pollution exposure. However, only a few studies have concentrated on the association between air pollution and adult asthma. Moreover, the results of these studies are controversial. Therefore, the present study aimed to analyze the influence of various pollutants on hospitalization due to asthma in adults. METHODS: A total of 1019 unrelated hospitalized adult asthma patients from Northeast China were recruited from 2014 to 2016. Daily average concentrations of air pollutants (particulate matter <2.5 µm [PM2.5], particulate matter <10 µm [PM10], sulfur dioxide [SO2], nitrogen dioxide [NO2], and carbon monoxide [CO]) were obtained from the China National Environmental Monitoring Centre website from 2014 to 2016. Cox logistic regression analysis was used to analyze the relationship between air pollutants and hospital admissions in adult asthma. RESULTS: The maximum odds ratio (OR) value for most air pollutants occurred on lag day 1. Lag day 1 was chosen as the exposure period, and 8 days before onset was chosen as the control period. Three pollutants (PM2.5, CO, and SO2) were entered into the regression equation, and the corresponding OR (95% confidence interval) was 0.995 (0.991-0.999), 3.107 (1.607-6.010), and 0.979 (0.968-0.990), respectively. CONCLUSIONS: A positive association between hospital admissions and the daily average concentration of CO was observed. CO is likely to be a risk factor for hospital admissions in adults with asthma.


Asunto(s)
Contaminación del Aire/efectos adversos , Asma/epidemiología , Hospitalización/estadística & datos numéricos , Contaminantes Atmosféricos/toxicidad , Monóxido de Carbono/toxicidad , China , Monitoreo del Ambiente/estadística & datos numéricos , Femenino , Humanos , Masculino , Oportunidad Relativa , Material Particulado/toxicidad , Factores de Riesgo , Dióxido de Azufre/toxicidad
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