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1.
Environ Pollut ; 352: 124126, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38735460

RESUMO

Human exposure to chromium (Cr) is common but little is known about its adverse effects on pregnancy outcomes. This study aimed to explore the association between Cr exposure and the risk of neural tube defects (NTDs) and the underlying mechanisms of Cr-induced NTDs. 593 controls and 408 NTD cases with placentas were included in this study. Chromium trichloride (Cr(III)) and potassium dichromate (Cr(VI)) were intragastrically administered to pregnant mice and the number of NTDs was recorded. The odds ratio for total NTDs in the highest exposure group in placenta was 4.18 (95% confidence interval (CI), 1.97-8.84). The incidence of fetal NTDs in mice administered with Cr(III) showed a dose-response relationship. Cr(VI) didn't show teratogenicity of NTDs whereas increased the stillbirth rate. Prenatal exposure to Cr(III) increased levels of oxidative stress and apoptosis in fetal mice. RNA-sequencing results indicated significant enrichment of the MAPK pathway. RT-qPCR and Western blot analysis revealed that Cr(III) induced increased expression of p-JNK, p-P38, and Casp3. Toxicological effects can be partly antagonized by antioxidant supplementation. High chromium exposure was associated with increased human NTD risks. Excessive Cr(III) exposure can induce NTDs in fetal mice by increasing apoptosis through upgrading oxidative stress and then activating JNK/P38 MAPK signaling pathway.

2.
Phys Chem Chem Phys ; 26(11): 8891-8899, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38426345

RESUMO

Mid-ultraviolet light (290-320 nm) can promote human vitamin D synthesis, which helps in the prevention and treatment of rickets and cartilage disease. For people who lack sufficient ultraviolet radiation all year round, it is significant to supplement the ultraviolet component in daily lighting sources. However, there are few luminous materials showing a combination of mid-ultraviolet light and white light emission on the market. Here, we designed a new material, Y2Sr(Ga1-yAly)4SiO12:xPr3+ (YSGAS:xPr3+), which achieves dual emission of 320 nm ultraviolet and white light from a single substrate with a single doped phosphor. Without Al3+ ions, the emission intensity of the Y2SrGa4SiO12:xPr3+ phosphor shows a contribution-dependent relationship, and concentration quenching due to exchange interaction. The crystal field environment was regulated by partially replacing Ga3+ ions with Al3+ ions. After introducing Al3+, YSGAS:xPr3+ phosphors exhibit dual ultraviolet emission (320 nm) and visible light emission. The emission color of YSGAS:xPr3+ can be adjusted by changing the Al3+ concentration, and Y2Sr(Ga0.6Al0.4)4SiO12:1%Pr3+ emits both ultraviolet light and white light. The LED device prepared by using the YSGAS:Pr3+ phosphor and chips shows a color temperature of 4858 K and appropriate CIE coordinates of (0.3474, 0.3390), indicating wide application prospects in the field of "health lighting" for particular populations.

5.
Int J Mol Sci ; 24(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36614263

RESUMO

Since brown rice extract is a rich source of biologically active compounds, the present study is aimed to quantify the major compounds in brown rice and to compare their cytoprotective potential against oxidative stress. The content of the main hydrophobic compounds in brown rice followed the order of cycloartenyl ferulate (CAF) (89.00 ± 8.07 nmol/g) >> α-tocopherol (αT) (19.73 ± 2.28 nmol/g) > γ-tocotrienol (γT3) (18.24 ± 1.41 nmol/g) > α-tocotrienol (αT3) (16.02 ± 1.29 nmol/g) > γ-tocopherol (γT) (3.81 ± 0.40 nmol/g). However, the percent contribution of CAF to the radical scavenging activity of one gram of whole brown rice was similar to those of αT, αT3, and γT3 because of its weaker antioxidant activity. The CAF pretreatment displayed a significant cytoprotective effect on the hydrogen peroxide-induced cytotoxicity from 10 µM, which is lower than the minimal concentrations of αT and γT required for a significant protection. CAF also enhanced the nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation coincided with the enhancement of the heme oxygenase-1 (HO-1) mRNA level. An HO-1 inhibitor, tin protoporphyrin IX (SnPP), significantly impaired the cytoprotection of CAF. The cytoprotective potential of CAF is attributable to its cycloartenyl moiety besides the ferulyl moiety. These results suggested that CAF is the predominant cytoprotector in brown rice against hydrogen peroxide-induced cytotoxicity.


Assuntos
Oryza , Oryza/metabolismo , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , alfa-Tocoferol/farmacologia , Heme Oxigenase-1/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo
6.
Opt Express ; 31(26): 43057-43066, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38178408

RESUMO

Antimony selenide (Sb2Se3) is a suitable candidate for a broadband photodetector owing to its remarkable optoelectronic properties. Achieving a high-performance self-powered photodetector through a desirable heterojunction still needs more efforts to explore. In this work, we demonstrate a broadband photodetector based on the hybrid heterostructure of Sb2Se3 nanorod arrays (NRAs) absorber and polymer acceptor (P(NDI2OD-T2), N2200). Owing to the well-matched energy levels between N2200 and Sb2Se3, the recombination of photogenerated electrons and holes in N2200/Sb2Se3 hybrid heterostructure is greatly inhibited. The photodetector can detect the wavelength from 405 to 980 nm, and exhibit high responsivity of 0.39 A/W and specific detectivity of 1.84 × 1011 Jones at 780 nm without bias voltage. Meanwhile, ultrafast response rise time (0.25 ms) and fall time (0.35 ms) are obtained. Moreover, the time-dependent photocurrent of this heterostructure-based photodetector keeps almost the same value after the storge for 40 days, indicating the excellent stability and reproducibility. These results demonstrate the potential application of a N2200/Sb2Se3 NRAs heterojunction in visible-near-infrared photodetectors.

7.
Pak J Med Sci ; 38(1): 145-149, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035416

RESUMO

OBJECTIVES: To investigate the risk factors for shoulder pain after stroke, and prevent its occurrence effectively. METHODS: The patients with stroke treated in our hospital between September 2016 and October 2020 were reviewed retrospectively. The medical records of the included patients including age, gender, lesion side, stroke duration, hospital stay, diabetes, hypertension, heart disease, limitation of shoulder joint activity, alcohol abuse, smoking, type of stroke, Ashworth scale, Brunnstrom stage, sensory disorders, and motor arm score of National Institutes of Health Stroke Scale (NIHSS) were collected and analyzed to determine the risk factors for shoulder pain after stroke. RESULTS: A total of 1390 patients were included based on the inclusion and exclusion criteria, consisting of 162 patients with shoulder pain after stroke and the prevalence was 11.6%. The included patients were divided into shoulder pain group and non-shoulder pain group. There were significant differences in age, stroke duration, hospital stay, diabetes, limitation of shoulder joint activity, Ashworth scale, Brunnstrom stage, sensory disorders, and motor arm score of NIHSS between the two groups (P < 0.05). Based on the multivariate regression analysis, the independent risk factors for shoulder pain after stroke included diabetes, limited shoulder joint activity, Brunnstrom grade I-III period, Ashworth 3-4 grade, motor arm score of NIHSS 3-4 points, and sensory disturbance. CONCLUSION: Great emphasis should be placed on the stroke patients with diabetes, limited shoulder joint activity, Brunnstrom grade I-III period, Ashworth 3-4 grade, motor arm score of NIHSS 3-4 points, or sensory disturbance, as these patients have higher risks for shoulder pain after stroke.

8.
Int Immunopharmacol ; 101(Pt B): 108216, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34634689

RESUMO

Herpes zoster (HZ) is a recurrent nerve tissue infection caused by the reactivation of varicella-zoster virus (VZV). At present, two vaccines, the live attenuated vaccine Zostavax™ and AS01B-adjuvanted recombinant subunit vaccine Shingrix™, are commercially available for HZ. The latter is superior to the former in terms of efficacy and duration of immunity in the elderly. In this study, we used glycoprotein E (gE) as an antigen, and investigated the effects of various adjuvants (MF59, MF59/CpG 2006, and MF59/QS-21) on the immune response of C57BL/6J mice to find an alternative adjuvant to AS01B-like adjuvant of liposome/QS-21/MPL. In addition to safety, the gE-specific antibody, IgG antibody subtype, and cytokine secretion by splenocytes, and cell-mediated immune responses were determined using ELISA and ELISPOT assays, respectively. Our results showed no significant effects on the body weight, temperature, or behavior of mice vaccinated with PBS or all adjuvanted vaccines. All adjuvanted vaccine groups showed significantly higher gE-specific IgG antibody levels than the gE-alone group on day 28 after the first vaccine dose. In addition, all adjuvants induced a remarkable increase in both IgG1 and IgG2b levels. However, MF59/QS-21 and MF59/CpG 2006 showed comparable capacities to those of liposome/QS-21/MPL in increasing the IgG2c levels, being superior to MF59. Further investigation revealed that MF59 only induced a limited increase in the levels of Th1 and Th2 cytokines, while MF59/QS-21, MF59/CpG 2006, and liposome/QS-21/MPL led to a significant increase in the secretion of interferon gamma (IFN-γ), IL-2, IL-4, and IL-10 and showed a Th1-biased immune response. Moreover, MF59/QS-21, MF59/CpG 2006, and liposome/QS-21/MPL adjuvanted vaccines resulted in comparable gE-specific IFN-γ + immune cell responses. These results suggest that the combination of MF59 with QS-21 or CpG 2006 may be a promising adjuvant candidate for subunit HZ vaccines. Further investigations are needed to illustrate their durability and efficacy in aged mice.


Assuntos
Herpes Zoster/prevenção & controle , Lipossomos , Nanoestruturas , Proteínas Virais/imunologia , Vacinas Virais/imunologia , Adjuvantes Imunológicos , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/classificação , Feminino , Imunoglobulina G/sangue , Interferon gama , Camundongos , Camundongos Endogâmicos C57BL , Subunidades Proteicas , Baço/citologia
9.
Biosci Biotechnol Biochem ; 85(10): 2161-2168, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34279597

RESUMO

The purpose of this study is to compare the potentials to exhibit biologically active antioxidant actions between white rice (WR) and brown rice (BR) in in vitro assays and a cellular model. The Trolox equivalent (TE) per 1 mg ethanol extract of WR for the 1,1-diphenyl-2-picrylhydrazyl assay was slightly higher than that of BR, whereas the TE per 1 g whole WR was much lower than that for BR. This tendency was very comparable to those for the oxygen radical absorbance capacity and total polyphenol content. Both of the ethanol extracts also similarly suppressed the hydrogen peroxide-induced cytotoxicity and enhanced the gene expression of drug-metabolizing enzymes. Based on the α-tocopherol quantity, its contribution to the cytoprotective effect of the rice extracts is very limited. Taken together, the ethanol extract of WR might be a qualitatively, but not quantitatively, equivalent source of antioxidative phytochemicals to that of BR.


Assuntos
Antioxidantes , Oryza , Etanol , Compostos Fitoquímicos
10.
Ecotoxicol Environ Saf ; 208: 111415, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33091767

RESUMO

OBJECTIVES: We aim to investigate association between WNT3A methylation and risk of non-syndromic cleft lip and/or palate (NSCL/P), and examine mediating effect of WNT3A methylation on the association of NSCL/P and lead (Pb) exposure in fetuses. METHODS: DNA methylation of WNT3A in umbilical cord blood was determined among 59 NSCL/P cases and 118 non-malformed controls. Mediation analysis was performed to evaluate the potential mediating effect of WNT3A methylation on association between concentrations of Pb in umbilical cord and risk for NSCL/P. Additionally, an animal experiment in which cleft palates were induced by lead acetate was conducted. RESULTS: The overall average methylation level of WNT3A was significant higher in NSCL/P cases as compared to controls. The risk for NSCL/P was increased by 1.90-fold with hypermethylation of WNT3A. Significant correlation was observed between concentrations of Pb in umbilical cord and methylation level of WNT3A. The hypermethylation of WNT3A had a mediating effect by 9.32% of total effect of Pb on NSCL/P risk. Gender-specific association between WNT3A methylation and NSCL/P was observed in male fetuses, and the percentage of the mediating effect increased to 14.28%. Animal experiment of mice showed that maternal oral exposure to lead acetate may result in cleft palate in offspring. CONCLUSION: Hypermethylation of WNT3A was associated with the risk for NSCL/P and may be partly explain the association between exposure to Pb and risk for NSCL/P. The teratogenic and fetotoxic effects of Pb were found in mice.


Assuntos
Fenda Labial/genética , Fissura Palatina/genética , Metilação de DNA , Substâncias Perigosas/toxicidade , Chumbo/toxicidade , Proteína Wnt3A/genética , Animais , Estudos de Casos e Controles , Genótipo , Humanos , Masculino , Análise de Mediação , Camundongos
11.
Environ Res ; 182: 109103, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31918316

RESUMO

BACKGROUND: Orofacial clefts (OFCs) are common kind of congenital malformations. The teratogenicity of uranium (U) has been documented in animal study that maternal exposure to U can increase incidence of external malformations including cleft palate. However, there is limited evidence of the association of in utero exposure to U with OFCs risk in humans. OBJECTIVE: This study aimed to investigate the association between in utero exposure to U and the risk of OFCs and its subtypes. METHOD: All subjects were from a case-control study in Shanxi Province, northern China. Eighty-four OFCs cases and 142 healthy controls were included in this study. We used U concentration in umbilical cord as biomarkers to represent intrauterine exposure, which was detected by inductively coupled plasma mass spectrometry. Unconditional logistic regression was used to investigated the association between U level and the risk of OFCs and its subtypes. RESULTS: The median of U concentration in umbilical cord is 0.745 ng/g in case group and 0.455 ng/g in control group. When the U concentration was divided into two categories, high level of U exposure increased the risk of OFCs (OR: 2.08, 95% CI: 1.13-3.86) and its subtype cleft lip with cleft palate (CLP) (OR: 2.72, 95% CI: 1.21-6.14). When divided into three categories, high level of U elevated the risk for OFCs (OR: 2.40, 95% CI: 1.14-5.06) and CLP (OR: 3.04, 95% CI: 1.20-7.74). Meanwhile, a dose-response relationship between the U concentration and the risk of total OFCs (P for trend = 0.009) and CLP (P for trend = 0.007) was found. CONCLUSION: Our study found that in utero exposure to high level of U was associated with increased risk of OFCs and its subtype CLP.


Assuntos
Fenda Labial , Fissura Palatina , Cordão Umbilical , Urânio , Estudos de Casos e Controles , China , Fenda Labial/induzido quimicamente , Fissura Palatina/induzido quimicamente , Feminino , Humanos , Recém-Nascido , Cordão Umbilical/química , Urânio/toxicidade
12.
Nanoscale Res Lett ; 13(1): 387, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30498864

RESUMO

We investigate the optical properties of InGaAs surface quantum dots (SQDs) in a composite nanostructure with a layer of similarly grown buried quantum dots (BQDs) separated by a thick GaAs spacer, but with varied areal densities of SQDs controlled by using different growth temperatures. Such SQDs behave differently from the BQDs, depending on the surface morphology. Dedicated photoluminescence (PL) measurements for the SQDs grown at 505 °C reveal that the SQD emission follows different relaxation channels while exhibiting abnormal thermal quenching. The PL intensity ratio between the SQDs and BQDs demonstrates interplay between excitation intensity and temperature. These observations suggest a strong dependence on the surface for carrier dynamics of the SQDs, depending on the temperature and excitation intensity.

13.
Opt Express ; 26(18): 23107-23118, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30184966

RESUMO

Single layer self-assembled InGaAs quantum dots (QDs) are manipulated by using different arsenic species on GaAs (100) surface. The As4 molecules are experimentally observed to be more promising than As2 to promote the formation of one-dimensionally-aligned QD-chain arrays. The lateral alignment of QDs and the corresponding formation of dot chains are explained by the anisotropic surface kinetics in combination with the different reactivities of the two molecules with bonding sites on the GaAs (100) surface. Photoluminescence (PL) measurements demonstrate that the spectra of the QD-chains broaden to higher energy and increases in intensity with increasing excitation laser power. The PL band of the QD-chains also exhibits a 9 meV reduction in linewidth as temperature increases starting from 8 K. These observations confirm an efficient lateral coupling between neighboring QDs and thereafter polarized QD emission, whereas the randomly distributed QDs grown with As2 show no preferential polarization. Such QD-chains exhibiting anisotropic properties have the potential for nanophotonics applications like electro-optic modulators with very low drive voltage and ultra-wide bandwidth operation.

14.
Opt Lett ; 38(13): 2209-11, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23811879

RESUMO

A novel chamber-channel system is proposed to achieve the bending of light at a 90 deg angle with relatively high transmission efficiencies. An ultrathin film is introduced into the chamber to couple more light into the system, which makes the chamber as a light absorber, while the channel serves as an output pathway to guide the light through the system. We show that the light propagation is significantly affected by the output position of the channels. By setting the output to specific positions, the device can be considered as a light switch, amplifier, or filter. This work holds great potential for controlling light in nanoscale photonic devices.

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