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1.
Inorg Chem ; 63(22): 10397-10402, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38767325

RESUMO

A micron-sized long-afterglow material, Sr2MgSi2O7:Eu,Ce, was utilized to conduct the hydrogen evolution reaction and oxygen evolution reaction, two half-reactions of water splitting, in the presence of sacrificial agents under both light and dark conditions for the first time. The as-synthesized Sr2MgSi2O7:Eu,Ce exhibited higher photocatalytic activity compared to that of the referenced Sr2MgSi2O7:Eu and Sr2MgSi2O7:Ce samples. Herein, in addition to benefiting from the long photogenerated carrier lifetime of long-afterglow materials, the higher photocatalytic activity was attributed to the conjugated electronic structure between Eu and Ce ions. This structure facilitates charge and energy transfer between them, leading to an enhanced photocatalytic efficiency. This research provides a new strategy for designing efficient long-afterglow material photocatalysts through the construction of conjugated electronic structures.

2.
Front Plant Sci ; 14: 1267191, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023894

RESUMO

In order to cope with the impact of global warming and frequent extreme weather, thermal acclimation ability is particularly important for plant development and growth, but the mechanism behind is still not fully understood. To investigate the role of NADH dehydrogenase-like complex (NDH) mediated cyclic electron flow (CEF) contributing to heat acclimation, wild type (WT) tobacco (Nicotiana tabacum) and its NDH-B or NDH-C, J, K subunits deficient mutants (ΔB or ΔCJK) were grown at 25/20°C before being shifted to a moderate heat stress environment (35/30°C). The photosynthetic performance of WT and ndh mutants could all eventually acclimate to the increased temperature, but the acclimation process of ndh mutants took longer. Transcriptome profiles revealed that ΔB mutant exhibited distinct photosynthetic-response patterns and stress-response genes compared to WT. Metabolite analysis suggested over-accumulated reducing power and production of more reactive oxygen species in ΔB mutant, which were likely associated with the non-parallel recovery of CO2 assimilation and light reactions shown in ΔB mutant during heat acclimation. Notably, in the warm night periods that could happen in the field, NDH pathway may link to the re-balance of excess reducing power accumulated during daytime. Thus, understanding the diurnal cycle contribution of NDH-mediated CEF for thermal acclimation is expected to facilitate efforts toward enhanced crop fitness and survival under future climates.

3.
Angew Chem Int Ed Engl ; 62(38): e202309624, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37526096

RESUMO

H2 O2 is a significant chemical widely utilized in the environmental and industrial fields, with growing global demand. Without sacrificial agents, simultaneous photocatalyzed H2 O2 synthesis through the oxygen reduction reaction (ORR) and water oxidation reaction (WOR) dual channels from seawater is green and sustainable but still challenging. Herein, two novel thiophene-containing covalent organic frameworks (TD-COF and TT-COF) were first constructed and served as catalysts for H2 O2 synthesis via indirect 2e- ORR and direct 2e- WOR channels. The photocatalytic H2 O2 production performance can be regulated by adjusting the N-heterocycle modules (pyridine and triazine) in COFs. Notably, with no sacrificial agents, just using air and water as raw materials, TD-COF exhibited high H2 O2 production yields of 4060 µmol h-1 g-1 and 3364 µmol h-1 g-1 in deionized water and natural seawater, respectively. Further computational mechanism studies revealed that the thiophene was the primary photoreduction unit for ORR, while the benzene ring (linked to the thiophene by the imine bond) was the central photooxidation unit for WOR. The current work exploits thiophene-containing COFs for overall photocatalytic H2 O2 synthesis via ORR and WOR dual channels and provides fresh insight into creating innovative catalysts for photocatalyzing H2 O2 synthesis.

4.
Nanomaterials (Basel) ; 13(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36985870

RESUMO

A heterostructure material g-C3N4/SrZrO3 was simply prepared by grinding and heating the mixture of SrZrO3 and g-C3N4. The morphology and structure of the synthesized photocatalysts were determined by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy (HRTEM) and infrared spectra. It showed visible light absorption ability and much higher photocatalytic activity than that of pristine g-C3N4 or SrZrO3. Under the optimal reaction conditions, the hydrogen production efficiency is 1222 µmol·g-1·h-1 and 34 µmol·g-1·h-1 under ultraviolet light irradiation and visible light irradiation, respectively. It is attributed to the higher separation efficiency of photogenerated electrons and holes between the cooperation of g-C3N4 and SrZrO3, which is demonstrated by photocurrent measurements.

5.
Int J Gen Med ; 14: 1983-1990, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34045890

RESUMO

BACKGROUND: Human papillomavirus (HPV) is linked to various cancers in males and females. The prevalence and genotype distribution of HPV vary depending on geographical region and the immunity provided by vaccines. Investigation of HPV epidemiology is of great meaning for the development of prevention programs. METHODS: From January 2017 to September 2019, using PCR-reverse dot blot hybridisation, we determined the HPV subtypes in 2801 patients 17-89 years old at the sexually transmitted diseases (STD) clinic of Tianjin Medical University General Hospital. RESULTS: The HPV infection rate was 50.79% in males and 50.64% in females. The most common HPV genotype in males and females was HPV6 (30.15% and 30.43%), followed by HPV16 (18.76% and 20.65%) and HPV11 (14.61% and 15.67%). Infection with a single HPV subtype predominated in both males and females, and the rate in males was higher than in females. By contrast, the rate of high-risk HPV (hrHPV) and low-risk HPV (lrHPV) mixed infection in females was higher than in males. Most HPV-positive patients were 20-39 years of age. The prevalence of infection with only hrHPV differed among the age groups; the peak age was 50 to 59 years. CONCLUSION: The HPV prevalence was higher among the STD clinic outpatients than the general population. Therefore, a large-scale survey of high-risk populations is needed. It is anticipated that HPV vaccines, regular education and physical examinations may have a significant impact on the prevention of HPV-related diseases in high-risk groups.

6.
Nanomaterials (Basel) ; 10(12)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371422

RESUMO

Strontium Titanate has a typical perovskite structure with advantages of low cost and photochemical stability. However, the wide bandgap and rapid recombination of electrons and holes limited its application in photocatalysis. In this work, a SrTiO3 material with surface oxygen vacancies was synthesized via carbon reduction under a high temperature. It was successfully applied for photocatalytic overall water splitting to produce clean hydrogen energy under visible light irradiation without any sacrificial reagent for the first time. The photocatalytic overall water splitting ability of the as-prepared SrTiO3-C950 is attributed to the surface oxygen vacancies that can make suitable energy levels for visible light response, improving the separation and transfer efficiency of photogenerated carriers.

7.
Nanomaterials (Basel) ; 10(5)2020 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-32397483

RESUMO

Colored titanium oxides are usually unstable in the atmosphere. Herein, a gray rutile titanium dioxide is synthesized by two-step calcination successively in a high-temperature reduction atmosphere and in a lower-temperature air atmosphere. The as-synthesized gray rutile TiO2 exhibits higher photocatalytic activity than that of white rutile TiO2 and shows high chemical stability. This is attributed to interior oxygen vacancies, which can improve the separation and transmission efficiency of the photogenerated carriers. Most notably, a formed surface passivation layer will protect the interior oxygen vacancies and provide long-term photocatalytic activity.

8.
Front Chem ; 7: 325, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31165056

RESUMO

In this work, a micron-sized three-way nitrogen-doped carbon tube covered with MoS2 nanosheets (TNCT@MoS2) was synthesized and applied in photocatalytic water splitting without any sacrificial agents for the first time. The micron-sized three-way nitrogen-doped carbon tube (TNCT) was facilely synthesized by the calcination of commercial sponge. The MoS2 nanosheets were assembled on the carbon tubes by a hydrothermal method. Compared with MoS2, the TNCT@MoS2 heterostructures showed higher H2 evolution rate, which was ascribed to the improved charge separation efficiency and the increased active sites afforded by the TNCT.

9.
Exp Biol Med (Maywood) ; 241(14): 1524-30, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27190272

RESUMO

The aim of this study was to investigate the association of three single nucleotide polymorphisms in the erythropoietin gene polymorphisms with diabetic retinopathy and additional role of gene-gene interaction on diabetic retinopathy risk. A total of 1193 patients (579 men, 614 women) with type 2 diabetes mellitus were selected, including 397 diabetic retinopathy patients and 796 controls (type 2 diabetes mellitus patients without diabetic retinopathy); the mean age of all participants was 56.7 ± 13.9 years. Three single nucleotide polymorphisms were selected: rs507392, rs1617640, and rs551238. The t-test was used for comparison of erythropoietin protein level erythropoietin levels in patients having different erythropoietin genotypes. Logistic regression model was used to examine the association between three single nucleotide polymorphisms and diabetic retinopathy. Odds ratio (OR) and 95% confident interval (95% CI) were calculated. Generalized multifactor dimensionality reduction was employed to analyze the impact of interaction among three single nucleotide polymorphisms on CVD risk. After covariates adjustment, the carriers of homozygous mutant of three single nucleotide polymorphisms have higher diabetic retinopathy risk than those with wild-type homozygotes, OR (95% CI) were 2.04 (1.12-2.35), 1.87 (1.10-2.41) and 1.15 (1.06-1.76), respectively. Generalized multifactor dimensionality reduction model indicated a significant three-locus model (p = 0.0010) involving rs507392, rs1617640, and rs551238. Overall, the three-locus models had a cross-validation consistency of 10 of 10, and had the testing accuracy of 60.72%. Subjects with TC or CC-TG or GG-AC or CC genotype have the highest diabetic retinopathy risk. In conclusion, our results support an important association of rs507392, rs1617640 and rs551238 minor allele of erythropoietin with increased diabetic retinopathy risk, and additional interaction among three single nucleotide polymorphisms.


Assuntos
Retinopatia Diabética/genética , Eritropoetina/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Povo Asiático/genética , Estudos de Casos e Controles , China , Feminino , Predisposição Genética para Doença , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances
10.
Dis Markers ; 2015: 609593, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26089587

RESUMO

To determine serum cytokine profiles in Graves' disease (GD) patients with or without active and inactive thyroid associated ophthalmopathy (TAO), we recruited 65 subjects: 10 GD only (without TAO), 25 GD + active TAO, 20 GD + TAO, and 10 healthy controls. Liquid chip assay was used to measure serum Th1/Th2/Th17 cytokines including IFN-γ (interferon-gamma), TNF-α (tumor necrosis factor-alpha), IL-1α (interleukin-1 alpha), IL-1Ra (IL-1 receptor antagonist), IL-2, IL-4, IL-6, and IL-17 and two chemokines: RANTES (regulated upon activation, normal T cell expressed and secreted) and IP-10 (IFN-γ-induced protein 10). Serum levels of TSH (thyroid stimulating hormone) receptor autoantibodies (TRAb) were measured using an enzyme linked immunosorbent assay. Compared with healthy controls, TAO patients showed significantly elevated serum levels of IFN-γ, TNF-α, IL-1α, IL-4, IL-6, IL-17, and IP-10. Comparing active and inactive TAO, serum Th1 cytokines IFN-γ and TNF-α were elevated in active TAO, while serum Th2 cytokine IL-4 was elevated in inactive TAO. Serum Th17 cytokine IL-17 was elevated in GD but reduced in both active and inactive TAO. A positive correlation was found between TRAb and IFN-γ, TNF-α, IL-1α, IL-2, IL-4, and IL-6. Taken together, serum Th1/Th2/Th17 cytokines and chemokines reflect TAO disease activity and may be implicated in TAO pathogenesis.


Assuntos
Citocinas/sangue , Doença de Graves/imunologia , Oftalmopatia de Graves/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adulto , Feminino , Doença de Graves/sangue , Oftalmopatia de Graves/sangue , Humanos , Imunoglobulinas Estimuladoras da Glândula Tireoide/sangue , Masculino , Pessoa de Meia-Idade , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia , Adulto Jovem
11.
Nan Fang Yi Ke Da Xue Xue Bao ; 30(5): 1066-8, 2010 May.
Artigo em Chinês | MEDLINE | ID: mdl-20501395

RESUMO

OBJECTIVE: To investigate the relationship between the dosage of irbesartan and the renal tissue structure in diabetic rats. METHODS: Male Wistar rats was given a single intraperitoneal dose (mg/kg) of streptozotocin to induce diabetes. The diabetic rats were randomized into 4 groups and received 4 weeks later 25 mg/kg (n=9), 50 mg/kg (n=9), 200 mg/kg (n=9) irbesartan intragastrically, or equal volume of water (model group, n=11) on a daily basis. Seven normal rats receiving with equal volume of water served as the normal control. All the rats were sacrificed after 8 weeks and the 24-hour albumin excretion, renal mass index and the volume of the glomerulus were measured. RESULTS: The 24-hour albumin excretion, renal mass index and volume of the glomerulus in the 3 irbesartan groups were significantly decreased as compare with those in the model group; the reductions in 50 and 200 mg/kg irbesartan groups were significant greater than those in 25 mg/kg irbesartan group. CONCLUSION: Irbesartan can decrease the 24-hour urinary albumin excretion and relive glomerulopathy in diabetic rats. Within a certain dose range, irbesartan produces a dose-dependent protective effect on the renal structures in the diabetic rats.


Assuntos
Compostos de Bifenilo/farmacologia , Diabetes Mellitus Experimental/patologia , Rim/patologia , Tetrazóis/farmacologia , Animais , Compostos de Bifenilo/efeitos adversos , Relação Dose-Resposta a Droga , Irbesartana , Masculino , Ratos , Ratos Wistar , Tetrazóis/efeitos adversos
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