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1.
RSC Adv ; 14(18): 12650-12657, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38645530

RESUMO

Tin oxide used in electron transport layer (ETL) exhibits key role in transmitting electrons and blocking holes in perovskite solar cells (PSCs) device. However, crystal tin oxide nanoparticles (NPs) become necessary to form SnO2 film by method of spin-coating, resulting in possible surface defect and cracks among SnO2 NPs, corresponding to unsatisfied performance PSCs. Herein, an amorphous tin oxide thin film is creatively in situ grew onto Fluorine-doped Tin Oxide (FTO) substrate as ETL. The designed solar cell device with structure of FTO/SnO2/MAPbI3/Sprio-OMeTAD/Ag owns a champion photoelectric conversion efficiency (PCE) up to 17.64%, 76.20% of filling coefficient (FF), and 1.09 V of open-circuit voltage (Voc), in comparing with 16.43%, 64.35% and 1.05 V for control group (crystal tin oxide as ETL), respectively. Besides, the champion device keeps 83.33% of initial PCE under nitrogen (N2) condition for one month, in comparison with 76.09% for control group. This work provides a viable strategy for facile preparing amorphous tin oxide film based ETL in perovskite solar cells.

2.
Clin Exp Pharmacol Physiol ; 51(6): e13859, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38643975

RESUMO

Previous study has demonstrated that the Dietary Inflammation Index (DII) played a role in the risk of inflammatory bowel disease (IBD), however, the prevalence and risk factors for IBD are distinct across locations and groups, and therefore, the findings are debatable and warrant further investigation. A total of 4363 participants were calculated in the National Health and Nutrition Examination Survey (NHANES) 2009 to 2010, of whom 1.21% self-reported a history of IBD. DII values were performed as a good predictor of dietary inflammation based on data from two 24-h dietary reviews in the NHANES database. Comparing the multifarious effects along with variations of the whole population by grouping populations according to DII quartiles, dietary inflammation levels increased progressively from DII quartile 1(Q1) to quartile 4(Q4). The association between DII and IBD was tested with multi-variable logistic regression models, subgroup analyses and weighted generalized additive models. Participants in the Q4 group showed the highest levels of C-reactive protein and reduced haemoglobin and albumin levels. Logistic regression confirmed the odds ratios (95% confidence intervals) of IBD for DII were 0.99 (0.86, 1.15), 0.97 (0.84, 1.13) and 0.80 (0.66, 0.98) in models 1, 2 and 3, respectively. The negative correlation between DII and IBD among United States adults from the NHANES database became increasingly apparent as covariates were adjusted. Subgroup analyses and smoothed curve fitting confirmed the inverse results. The study revealed that DII was correlated with the overall physical well-being of participants. However, there was no significant association between DII and IBD.


Assuntos
Dieta , Inflamação , Doenças Inflamatórias Intestinais , Inquéritos Nutricionais , Humanos , Doenças Inflamatórias Intestinais/epidemiologia , Masculino , Feminino , Adulto , Inflamação/epidemiologia , Inflamação/sangue , Dieta/efeitos adversos , Pessoa de Meia-Idade , Fatores de Risco , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Estados Unidos/epidemiologia
3.
Front Aging Neurosci ; 16: 1363458, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38566826

RESUMO

Alzheimer's disease (AD), referring to a gradual deterioration in cognitive function, including memory loss and impaired thinking skills, has emerged as a substantial worldwide challenge with profound social and economic implications. As the prevalence of AD continues to rise and the population ages, there is an imperative demand for innovative imaging techniques to help improve our understanding of these complex conditions. Photoacoustic (PA) imaging forms a hybrid imaging modality by integrating the high-contrast of optical imaging and deep-penetration of ultrasound imaging. PA imaging enables the visualization and characterization of tissue structures and multifunctional information at high resolution and, has demonstrated promising preliminary results in the study and diagnosis of AD. This review endeavors to offer a thorough overview of the current applications and potential of PA imaging on AD diagnosis and treatment. Firstly, the structural, functional, molecular parameter changes associated with AD-related brain imaging captured by PA imaging will be summarized, shaping the diagnostic standpoint of this review. Then, the therapeutic methods aimed at AD is discussed further. Lastly, the potential solutions and clinical applications to expand the extent of PA imaging into deeper AD scenarios is proposed. While certain aspects might not be fully covered, this mini-review provides valuable insights into AD diagnosis and treatment through the utilization of innovative tissue photothermal effects. We hope that it will spark further exploration in this field, fostering improved and earlier theranostics for AD.

4.
Cell Prolif ; : e13635, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594962

RESUMO

Age-related macular degeneration (AMD) and diabetic retinopathy (DR) are the world's leading causes of blindness. The retinal pigment epithelium (RPE) and vascular endothelial cell exposed to oxidative stress is the major cause of AMD and DR. DJ-1, an important endogenous antioxidant, its overexpression is considered as a promising antioxidant treatment for AMD and DR. Here, we modified the tetrahedral frame nucleic acids (tFNAs) with DJ-1 saRNAs as a delivery system, and synthesized a novel nanocomplex (tFNAs-DJ-1 saRNAs). In vitro studies show that tFNAs-DJ-1 saRNAs can efficiently transfer DJ-1 saRNAs to human umbilical vein endothelial cells (HUVECs) and ARPE-19s, and significantly increased their cellular DJ-1 level. Reactive oxygen species expression in H2O2-treated HUVECs and ARPE-19s were decreased, cell viability was enhanced and cell apoptosis were inhibited when tFNAs-DJ-1 saRNAs were delivered. Moreover, tFNAs-DJ-1 saRNAs preserved mitochondrial structure and function under oxidative stress conditions. In the aspect of molecular mechanism, tFNAs-DJ-1 saRNAs activated Erk and Nrf2 pathway, which might contribute to its protective effects against oxidative stress damage. To conclude, this study shows the successfully establishment of a simple but effective delivery system of DJ-1 saRNAs associated with antioxidant effects in AMD and DR, which may be a promising agent for future treatment in oxidative stress-related retinal disorders.

5.
J Stroke Cerebrovasc Dis ; 33(7): 107737, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38688395

RESUMO

BACKGROUND: The association between hypothyroidism and stroke remains controversial and the association between hypothyroidism and stroke subtypes has not been satisfactorily researched. This study aimed to explore the causal effect of hypothyroidism on the risk of stroke and its subtypes by Mendelian randomization (MR) analysis. METHODS: Single nucleotide polymorphisms (SNPs) were selected from published genome-wide association studies (GWAS) meta-analysis as instrumental variables (IVs) for hypothyroidism. As outcomes, summary GWAS data for stroke and its subtypes were obtained from two other large GWAS meta-analyses, including any stroke (AS), any ischemic stroke (AIS), large vessel stroke (LAS), cardiogenic embolic stroke (CES), small vessel stroke (SVS), and intracranial hemorrhage (ICH). Univariate Mendelian randomization (UVMR) and multivariate Mendelian randomization (MVMR) were used to assess the causal effect of hypothyroidism on stroke and its subtypes. RESULTS: In UVMR, genetically predicted hypothyroidism was significantly associated with LAS (OR = 1.14, 95CI = 1.02-1.27) and SVS (OR = 1.14, 95CI = 1.04-1.25), but not with AS, AIS, CES, and ICH. The results of the MVMR showed that after adjusting for smoking, alcohol consumption, hypertension, diabetes, low-density lipoprotein cholesterol (LDL-c), and body mass index (BMI), the causal association between hypothyroidism and SVS remained significant, while the association between hypothyroidism and LAS became nonsignificant. CONCLUSION: Hypothyroidism is causally associated with risk for LAS and SVS, but not for other stroke subtypes. Hypothyroidism may be an independent risk factor for SVS, and vascular risk factors play an important role in hypothyroidism causing LAS.

6.
Aging (Albany NY) ; 16(5): 4363-4377, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38441564

RESUMO

BACKGROUND: Neuronal injury in chronic cerebral hypoperfusion (CCH) is the main pathogenic factor of vascular dementia (VD). Clinically, there isn't a drug specifically for VD; instead, the majority of medications used to treat Alzheimer's disease (AD) are also used to treat VD. Based on the proven anti-inflammatory and antioxidant effects of Probucol, we hypothesized that it may have therapeutic effects on VD, but more research is required to determine its exact mechanism of action. METHODS: In vivo experiment: We used SD rats and most commonly used bilateral carotid artery occlusion (2-VO) in VD for modeling. After successful modeling, SD rats were given Probucol 3.5 mg/kg/day for 8 weeks to evaluate the therapeutic effect. In vitro experiment: BV-2 microglia of rats were cultured and divided into Control group and Probucol group. Each group was treated with hypoxia-hypoglycemia, hypoxia-hypoglycemia hydrogen peroxide and hypoxia-hypoglycemia hydrogen peroxide Syk inhibitor respectively. RESULTS: The results of immunofluorescence and Western blot showed that Probucol could significantly improve the cognitive impairment induced by CCH, and the neuronal damage was also attenuated. On the one hand, the underlying mechanism of Probucol was to reduce oxidative stress and cell apoptosis of hippocampal neurons by inhibiting the expression of phosphorylated spleen tyrosine kinase (P-Syk); On the other hand, it exerted a protective effect by reducing NLRP3-dependent cell pyroptosis and inhibiting neuroinflammation induced by microglia activation. CONCLUSION: Probucol could reduce oxidative stress and cell apoptosis by inhibiting the Syk/ROS signaling pathway, thereby improving CCH-induced cognitive impairment in vitro and in vivo.


Assuntos
Isquemia Encefálica , Demência Vascular , Hipoglicemia , Ratos , Animais , Demência Vascular/tratamento farmacológico , Demência Vascular/etiologia , Demência Vascular/metabolismo , Probucol/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Ratos Sprague-Dawley , Piroptose , Peróxido de Hidrogênio/farmacologia , Isquemia Encefálica/metabolismo , Hipocampo/metabolismo , Hipóxia/metabolismo
7.
Front Microbiol ; 15: 1323160, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500581

RESUMO

The acceleration of the nitrogen cycle and the nitrogen excess observed in some coastal waters has increased interest into understanding the biochemical and molecular basis of nitrogen metabolism in various microorganisms. To investigate nitrogen metabolism of a novel heterotrophic nitrification and aerobic denitrification bacterium Klebsiella aerogenes strain (B23) under nitrogen-rich conditions, we conducted physiological and transcriptomic high-throughput sequencing analyses on strain B23 cultured on potassium nitrate-free or potassium nitrate-rich media. Overall, K. aerogenes B23 assimilated 82.47% of the nitrate present into cellular nitrogen. Further, 1,195 differentially expressed genes were observed between K. aerogenes B23 cultured on potassium nitrate-free media and those cultured on potassium nitrate-rich media. Gene annotation and metabolic pathway analysis of the transcriptome were performed using a series of bioinformatics tools, including Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and Non-Redundant Protein Database annotation. Accordingly, the nitrogen metabolism pathway of K. aerogenes B23 was analyzed; overall, 39 genes were determined to be involved in this pathway. Differential expression analysis of the genes involved in the nitrogen metabolism pathway demonstrated that, compared to the control, FNR, NarK/14945, fdx, gshA, proB, proA, gapA, argH, artQ, artJ, artM, ArgR, GAT1, prmB, pyrG, glnS, and Ca1 were significantly upregulated in the nitrogen-treated K. aerogenes B23; these genes have been established to be involved in the regulation of nitrate, arginine, glutamate, and ammonia assimilation. Further, norV, norR, and narI were also upregulated in nitrogen-treated K. aerogenes B23; these genes are involved in the regulation of NO metabolism. These differential expression results are important for understanding the regulation process of key nitrogen metabolism enzyme genes in K. aerogenes B23. Therefore, this study establishes a solid foundation for further research into the expression regulation patterns of nitrogen metabolism-associated genes in K. aerogenes B23 under nitrogen-rich conditions; moreover, this research provides essential insight into how K. aerogenes B23 utilizes nutritional elements.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38441136

RESUMO

BACKGROUND AND AIMS: Colonoscopy is a critical diagnostic tool for colorectal diseases; however, its effectiveness depends on adequate bowel preparation (BP). This study aimed to develop a machine learning predictive model based on Chinese adults for inadequate BP . METHODS: A multicenter, prospective study was conducted on adult outpatients undergoing colonoscopy from January 2021 to May 2023. Data on patient characteristics, comorbidities, medication use, and BP quality were collected. Logistic regression and four machine learning models (support vector machines, decision trees, extreme gradient boosting, and bidirectional projection network) were used to identify risk factors and predict inadequate BP. RESULTS: Of 3217 patients, 21.14% had inadequate BP. The decision trees model demonstrated the best predictive capacity with an area under the receiver operating characteristic curve of 0.80 in the validation cohort. The risk factors at the nodes included body mass index, education grade, use of simethicone, diabetes, age, history of inadequate BP, and longer interval. CONCLUSION: The decision trees model we created and the identified risk factors can be used to identify patients at higher risk for inadequate BP before colonoscopy, for whom more PEG or auxiliary medication should be used.

9.
Chem Biol Drug Des ; 103(3): e14481, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38458969

RESUMO

Studies have shown that saikosaponin D (SSD) has favorable neurotherapeutic effects. Therefore, the objective of this study was to explore the efficacy and possible molecular mechanisms of SSD on pilocarpine (PP)-induced astrocyte injury. Primary astrocytes were isolated from juvenile rats and identified using immunofluorescence. The cells were treated with PP and/or SSD for 6 h and 12 h, respectively, followed by measurement of their viability through 3-(4,5-dimethylthiazol)-2,5-diphenyl-tetrazolium bromide (MTT) assay. Next, quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure the expression levels of Glial fibrillary acidic protein (GFAP), C3, S100 calcium binding protein A10 (S100a10), pentraxin 3 (Ptx3), toll-like receptor 4 (TLR4), and RAG in astrocytes after different treatments. Enzyme-linked immunosorbent assay and biochemical tests were utilized to evaluate the level of inflammatory factors [interleukin (IL)-1ß, IL-6, and tumor necrosis factor alpha (TNF-α)] secreted by cells and the content of oxidative stress-related factors (malondialdehyde [MDA] and glutathione [GSH]) or enzyme activity (catalase [CAT] and glutathione peroxidase [GPX]) in cells. The JC-1 mitochondrial membrane potential (MMP) fluorescence probe was used to measure the MMP in astrocytes. Additionally, western blot was applied to test the expression of proteins related to the nod-like receptor protein 3 (NLRP3)/caspase-1 signaling pathway. PP treatment (1 mM) induced cell injury by significantly reducing the viability of astrocytes and expression of cellular markers. SSD treatment (4 µM) had no toxicity to astrocytes. Besides, SSD (4 µM) treatment could significantly up-regulate the cell viability and marker expression of PP-induced astrocytes. Furthermore, SSD could be employed to inhibit inflammation (reduce IL-1ß, IL-6, and TNF-α levels) and oxidative stress (decrease MDA level, elevate GSH level, the activity of CAT and GPX), and ameliorate mitochondrial dysfunction (upregulate JC-1 ratio) in PP-induced astrocytes. Moreover, further mechanism exploration revealed that SSD treatment significantly reduced the activity of the NLRP3/caspase-1 signaling pathway activated by PP induction. SSD increased cell viability, inhibited inflammation and oxidative stress response, and ameliorated mitochondrial dysfunction in PP-induced astrocyte injury model, thus playing a neuroprotective role. The mechanism of SSD may be related to the inhibition of the NLRP3/caspase-1 inflammasome.


Assuntos
Benzimidazóis , Carbocianinas , Doenças Mitocondriais , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ácido Oleanólico/análogos & derivados , Saponinas , Ratos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Astrócitos/metabolismo , Astrócitos/patologia , Pilocarpina/toxicidade , Fator de Necrose Tumoral alfa/genética , Caspases/metabolismo , Interleucina-6 , Transdução de Sinais , Inflamação/metabolismo
10.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(1): 43-48, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38433630

RESUMO

Objective To analyze the correlations between platelet-related parameters and the incidence of anxiety and depression in the patients undergoing peritoneal dialysis(PD),and evaluate the efficacy of the parameters in the diagnosis of anxiety and depression in PD patients. Methods A total of 245 patients undergoing PD in the First Affiliated Hospital of Hebei North University from September 2022 to February 2023 were enrolled.The generalized anxiety scale(GAD-7) and the patient health questionnaire(PHQ-9) were used to evaluate the anxiety and depression of the patients,respectively.The personal information and biochemical indicators of the patients were collected,and the platelet count(PLT),mean platelet volume(MPV),and platelet distribution width(PDW) were measured.Logistic regression was adopted to analyze the relationships of platelet-related parameters with anxiety and depression in PD patients. Results Among the 245 patients undergoing PD,the incidences of anxiety and depression were 15.9% and 38.0%,respectively.There were differences in the dialysis period(Z=-2.358,P=0.018;Z=-3.079,P=0.002),MPV(Z=-4.953,P<0.001;Z=-7.878,P<0.001),and PDW(Z=-4.587,P<0.001;Z=-7.367,P<0.001) between the anxiety group and the non-anxiety group as well as between the depression group and the non-depression group.The correlation analysis showed that MPV(r=0.358,P<0.001;r=0.489,P<0.001) and PDW(r=0.340,P<0.001;r=0.447,P<0.001) were positively correlated with anxiety and depression in the patients undergoing PD.The Logistic regression model showed that MPV(P=0.022,P=0.011),PDW(P=0.041,P=0.018),and dialysis period(P=0.011,P=0.030) were independent risk factors for the anxiety and depressive state in PD patients.The areas under the receiver operating characteristic curve of MPV in the diagnosis of anxiety and depression in PD patients were 0.750 and 0.800,respectively,and those of PDW were 0.732 and 0.780,respectively. Conclusion MPV and PDW have high efficacy in the diagnosis of anxiety and depression associated with PD and can be used as objective indicators to evaluate the anxiety and depression in the patients undergoing PD.


Assuntos
Ansiedade , Diálise Peritoneal , Humanos , Diálise Peritoneal/efeitos adversos , Hospitais , Modelos Logísticos , Curva ROC
11.
World J Clin Cases ; 12(6): 1094-1103, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38464922

RESUMO

BACKGROUND: Accumulating evidence suggests that the gut microbiome is involved in the pathogenesis of insulin resistance (IR). However, the link between two of the most prevalent bowel disorders, chronic diarrhea and constipation, and the triglyceride glucose (TyG) index, a marker of IR, has not yet been investigated. AIM: To investigate the potential association between TyG and the incidence of chronic diarrhea and constipation. METHODS: This cross-sectional study enrolled 2400 participants from the National Health and Nutrition Examination Survey database from 2009-2010. TyG was used as an exposure variable, with chronic diarrhea and constipation as determined by the Bristol Stool Form Scale used as the outcome variables. A demographic investigation based on TyG quartile subgroups was performed. The application of multivariate logistic regression models and weighted generalized additive models revealed potential correlations between TyG, chronic diarrhea, and constipation. Subgroup analyses were performed to examine the stability of any potential associations. RESULTS: In the chosen sample, chronic diarrhea had a prevalence of 8.00%, while chronic constipation had a prevalence of 8.04%. In multiple logistic regression, a more prominent positive association was found between TyG and chronic diarrhea, particularly in model 1 (OR = 1.45; 95%CI: 1.17-1.79, P = 0.0007) and model 2 (OR = 1.40; 95%CI: 1.12-1.76, P = 0.0033). No definite association was observed between the TyG levels and chronic constipation. The weighted generalized additive model findings suggested a more substantial positive association with chronic diarrhea when TyG was less than 9.63 (OR = 1.89; 95%CI: 1.05-3.41, P = 0.0344), and another positive association with chronic constipation when it was greater than 8.2 (OR = 1.74; 95%CI: 1.02-2.95, P = 0.0415). The results of the subgroup analyses further strengthen the extrapolation of these results to a wide range of populations. CONCLUSION: Higher TyG levels were positively associated with abnormal bowel health.

12.
Nutr Neurosci ; : 1-6, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347678

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a degenerative disease of the nervous system. Observational studies have found an association between plant food intake and AD. However, it is unclear whether this association is influenced by confounding factors. We aimed to explore the causal relationship between plant-based diet and the risk of AD using two-sample Mendelian randomization. MATERIALS AND METHODS: We obtained datasets of exposure from the IEU Open GWAS project, including dried fruit intake, fresh fruit intake, raw vegetable intake, cooked vegetable intake, and cereal intake. The summary data for AD were obtained from a large GWAS meta-analysis containing 71,880 cases and 383,378 controls. RESULTS: Increased intake of dried fruits was associated with a reduced risk of AD (IVW: OR = 0.88, 95CI = 0.82-0.95). No causal association was found between the intake of other foods and AD. CONCLUSION: This MR study suggests that genetically predicted increased intake of dried fruits is a causal protective factor for AD.

13.
Food Chem X ; 21: 101148, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38304043

RESUMO

Cellulase can increase the soluble dietary fiber (SDF) content in Rosa roxburghii Tratt (RRT), but the effects on polyphenol content, bioactivity, and flavor are unknown. This study analyzed the changes in SDF content, total phenolic content, antioxidant activity and flavor before and after cellulase treatment. Cellulase treatment increased the SDF and total phenolic content of RRT by 13 % (P < 0.05) and 25.68 % (P < 0.05), respectively, and increased the antioxidant activity. HS-GC-IMS identified a total of 42 volatile compounds present, and ROAV analysis revealed that the characteristic aroma compounds of RRT were mainly aldehydes, alcohols, and ethers. The electronic nose and tongue results were consistent with the HS-GC-IMS analysis, indicating the positive effect of cellulase on the quality of RRT. Cellulase treatment significantly improved the oxidative activity and flavor performance of RRT. These results of RRT, providing practical guidance for improving the flavor and product quality.

14.
Adv Healthc Mater ; 13(11): e2303779, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38288884

RESUMO

Nanomaterials that generate reactive oxygen species (ROS) upon light irradiation have significant applications in various fields, including photodynamic therapy (PDT) that is widely recognized as a highly momentous strategy for the eradication of cancer cells. However, the ROS production rate of photosensitizers, as well as the tumor hypoxia environment, are two major challenges that restrict the widespread application of PDT. In this study, a cancer-thylakoid hybrid membrane-camouflaged thulium oxide nanoparticles (Tm2O3) for tumor-homing phototherapy through dual-stage-light-guided ROS generation and oxygen self-supply is developed. Tm2O3 as a type II photosensitizer are viable for NIR-stimulated ROS generation due to the unique energy levels, large absorption cross section, and long lifetime of the 3H4 state of Tm ions. The thylakoid membrane (TK) plays a catalase-like role in converting hydrogen peroxide into oxygen and also acts as a natural photosensitizer that can generate lethal ROS through electron transfer when exposed to light. In addition, fluorescence dye DiR is embedded in the hybrid membrane for in vivo tracing as well as photothermal therapy. Results show that tumors in Tm2O3@TK-M/DiR group are effectively ablated following dual-stage-light irradiation, highlighting the promising potential of rare-earth element-based type II photosensitizers in various applications.


Assuntos
Nanopartículas , Oxigênio , Fotoquimioterapia , Fármacos Fotossensibilizantes , Espécies Reativas de Oxigênio , Túlio , Animais , Túlio/química , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Humanos , Oxigênio/química , Oxigênio/metabolismo , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Nanopartículas/química , Fotoquimioterapia/métodos , Óxidos/química , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/metabolismo , Fototerapia/métodos
15.
Adv Sci (Weinh) ; 11(12): e2306518, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38234238

RESUMO

Colloidal semiconductor nanoplatelets (NPLs) have emerged as low-cost and free-standing alternates of traditional quantum wells. The giant heavy- and light-hole splitting in NPLs allows for efficient optical spin injection. However, the electron spin lifetimes for prototypical CdSe NPLs are within a few picoseconds, likely limited by strong electron-hole exchange in these quantum- and dielectric-confined materials. Here how this hurdle can be overcome with engineered NPL-heterostructures is demonstrated. By constructing type-I CdSe/ZnS core/shell NPLs, dielectric screening inside the core is strongly enhanced, prolonging the electron spin polarization time (τesp) to over 30 ps (or 60 ps electron spin-flip time). Alternatively, by growing type-II CdSe/CdTe core/crown NPLs to spatially separate electron and hole wavefunctions, the electron-hole exchange is strongly suppressed, resulting in τesp as long as 300 ps at room temperature. This study not only exemplifies how the well-established synthetic chemistry of colloidal heterostructures can aid in spin dynamics control but also establishes the feasibility of room-temperature coherent spin manipulation in colloidal NPLs.

16.
J Nutr ; 154(1): 79-86, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37951389

RESUMO

BACKGROUND: Numerous research works have investigated the association between tea consumption and the risk of acute cerebrovascular events; however, the results are inconsistent. OBJECTIVES: We used Mendelian randomization (MR) to evaluate the causal association between tea intake and several acute cerebrovascular events, including any ischemic stroke, large atherosclerotic stroke (LAS), cardiogenic embolic stroke (CES), small vessel stroke (SVS), intracranial hemorrhage (ICH), and subarachnoid hemorrhage (SAH). METHODS: We obtained summary genome-wide association study (GWAS) data on tea intake and acute cerebrovascular events in populations of European ancestry. The GWAS on tea intake is derived from the UK Biobank, where we have chosen single-nucleotide polymorphisms (SNPs) closely associated with it as instrumental variables. We also obtained summary data on ischemic stroke from a GWAS meta-analysis, as well as summary data on ICH and SAH from the FinnGen study. We first explored the causal association between tea intake and several acute cerebrovascular events using univariate Mendelian randomization (UVMR), and then further assessed the causal association between tea intake and SVS using multivariate Mendelian randomization (MVMR) corrected for multiple confounders. RESULTS: In UVMR, genetically predicted increases in tea intake were linked to a lower risk of SVS (OR: 0.58; 95% CI: 0.39, 0.86). There was no causal association between tea intake and the risk of other acute cerebrovascular events. In the MVMR, our results show that there was still a significant causal association between drinking tea and SVS, after adjusting body mass index, total cholesterol, low-density lipoprotein cholesterol, diabetes, hypertension, smoking, and alcohol consumption. CONCLUSION: This MR study provides new genetic evidence that increased tea intake reduces the risk of SVS in the European population. However, possibly because of limited statistical power, the study did not find that tea consumption reduced the risk of several other acute cerebrovascular events.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Estudo de Associação Genômica Ampla , Acidente Vascular Cerebral/genética , LDL-Colesterol , Polimorfismo de Nucleotídeo Único , Chá , Análise da Randomização Mendeliana , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Small ; 20(15): e2307620, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009487

RESUMO

Triboelectric nanogenerators (TENGs) have emerged as a promising technology for harvesting mechanical energy from the ambient environment. However, developing tribopositive materials with strong piezoelectric effects and high electron-donating ability still remains a challenge. Herein, poly(ethylene glycol) monomethyl ether (mPEG) to soft poly(lactic acid) (PLA) is adopted, then PLA/mPEG nanofibers are fabricated under electrospinning and used as the tribopositive material for fabricating robust power density TENGs. The crystallinity and dynamic mechanical properties of PLA/mPEG nanofibers are investigated. The results revealed that the incorporation of mPEG provided an effective approach to elevate the electron-donating ability and charge transfer efficiency in PLA. The PLA/mPEG-based TENGs achieved a high open-circuit voltage of 342.8 V, a short-circuit current of 38.5 µA, and a maximum power density of 116.21 W m-2 over a 2 cm2 contact area at an external load of 106 Ω, respectively. Strikingly, excellent stability and durability are demonstrated after continuous cycles up to 104 cycles. Noteworthy, the TENGs are explored for self-powered sensing applications, with seven TENG units integrated to act as self-powered sensors playing music through buzzers when pressed by fingers. Eventually, this work provides new insights into tuning the structures and properties of electrospun polymers to reinforce the TENG output and self-powered systems.

19.
Adv Mater ; 36(7): e2308979, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38009644

RESUMO

Colloidal quantum-dot (QD) lasing is normally achieved in close-packed solid-state films, as a high QD volume fraction is required for stimulated emission to outcompete fast Auger decay of optical-gain-active multiexciton states. Here a new type of liquid optical-gain medium is demonstrated, in which compact compositionally-graded QDs (ccg-QDs) that feature strong suppression of Auger decay are liquefied using a small amount of solvent. Transient absorption measurements of ccg-QD liquid suspensions reveal broad-band optical gain spanning a wide spectral range from 560 (green) to 675 nm (red). The gain magnitude is sufficient to realize a two-color amplified spontaneous emission (ASE) at 637 and 594 nm due to the band-edge (1S) and the excited-state (1P) transition, respectively. Importantly, the ASE regime is achieved using quasicontinuous excitation with nanosecond pulses. Furthermore, the ASE is highly stable under prolonged excitation, which stands in contrast to traditional dyes that exhibit strong degradation under identical excitation conditions. These observations point toward a considerable potential of high-density ccg-QD suspensions as liquid, dye-like optical gain media that feature readily achievable spectral tunability and stable operation under intense photoexcitation.

20.
Adv Mater ; 36(6): e2309420, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38009823

RESUMO

Lead halide perovskite quantum dots (QDs) have recently emerged as a promising material platform for quantum information processing owing to their strong light-matter interaction and relatively long-lived optical and spin coherences. In particular, the coherence of the fine-structure bright excitons is sustainable up to room temperature and can be observed even at an ensemble level. Here modulation of the polarization of these excitons in CsPbI3 QDs and manipulation of their time-domain coherent dynamics using a longitudinal magnetic field are demonstrated. The manipulation is realized using femtosecond quantum beat spectroscopy performed with both circularly- and linearly-polarized pulses. The results are well captured by the density of matrix simulation and are picturized using a Bloch sphere. This study forms the basis for preparing arbitrary coherent superpositions of excitons in perovskite QDs for an array of quantum technologies under near-ambient conditions.

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