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1.
BMJ Open ; 11(11): e048384, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34725073

RESUMO

OBJECTIVE: Hypertension (HTN) is common in systemic lupus erythematosus (SLE), representing a key risk factor for cardiovascular and renal disease. We described HTN treatment patterns in SLE, evaluated uncontrolled HTN according to Canadian and American guidelines and identified factors associated with uncontrolled HTN. METHODS: We performed a cross-sectional study, identifying all McGill Lupus Clinic registry patients with an annual visit between January 2017 and May 2019 who were taking HTN medications. We excluded those taking medications only for another indication (eg, Raynaud's). We determined the frequency of uncontrolled HTN according to Canadian and American College of Cardiology/American Heart Association guidelines. Multivariate logistic regression (adjusted for age, sex and race/ethnicity) evaluated if uncontrolled HTN was more common with high body mass index (BMI), longer SLE duration, high disease activity, renal damage, multiple concomitant antihypertensives, prednisone and non-steroidal anti-inflammatory drugs. RESULTS: Of 442 patients with SLE, 108 were taking medications to treat HTN, and 38 took multiple medications concurrently. Angiotensin-receptor blockers were most common, followed by calcium channel blockers, diuretics, angiotensin-converting enzyme inhibitors and beta blockers. Among the 108 patients, 39.8% (n=43) had blood pressure (BP) >140/90 mm Hg, while 66.7% (n=72) had BP >130/80 mm Hg. In multivariate analyses, uncontrolled HTN (>130/80 mm Hg) was more likely in Caucasians (OR 2.72, 95% CI 1.12 to 6.78) and patients with higher BMI (OR 1.08, 95% CI 1.00 to 1.19). Patients with renal damage had better HTN control (OR 0.39, 95% CI 0.16 to 0.97). We could not draw definitive conclusions regarding other variables. CONCLUSION: Caucasians and patients with higher BMI had more uncontrolled HTN. The negative association with renal damage is reassuring, as controlled BP is key for renal protection.

2.
J Am Heart Assoc ; 10(22): e022011, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34726071

RESUMO

Background Acute myocardial infarction (AMI) is one of the leading causes of cardiovascular morbidity and mortality worldwide. Pyroptosis is a form of inflammatory cell death that plays a major role in the development and progression of cardiac injury in AMI. However, the underlying mechanisms for the activation of pyroptosis during AMI are not fully elucidated. Methods and Results Here we show that RBP4 (retinol-binding protein 4), a previous identified proinflammatory adipokine, was increased both in the myocardium of left anterior descending artery ligation-induced AMI mouse model and in ischemia-hypoxia‒induced cardiomyocyte injury model. The upregulated RBP4 may contribute to the activation of cardiomyocyte pyroptosis in AMI because overexpression of RBP4 activated NLRP3 (nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3) inflammasome, promoted the precursor cleavage of Caspase-1, and subsequently induced GSDMD (gasdermin-D)-dependent pyroptosis. In contrast, knockdown of RBP4 alleviated ischemia-hypoxia‒induced activation of NLRP3 inflammasome signaling and pyroptosis in cardiomyocytes. Mechanistically, coimmunoprecipitation assay showed that RBP4 interacted directly with NLRP3 in cardiomyocyte, while genetic knockdown or pharmacological inhibition of NLRP3 attenuated RBP4-induced pyroptosis in cardiomyocytes. Finally, knockdown of RBP4 in heart decreased infarct size and protected against AMI-induced pyroptosis and cardiac dysfunction in mice. Conclusions Taken together, these findings reveal RBP4 as a novel modulator promoting cardiomyocyte pyroptosis via interaction with NLRP3 in AMI. Therefore, targeting cardiac RBP4 might represent a viable strategy for the prevention of cardiac injury in patients with AMI.

3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(6): 1001-1005, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34841768

RESUMO

Objective: To investigate the feasibility of low-dose CT scan of the temporal bone combined with reconstruction matrix size of 1 024×1 024 and the effect of the reconstruction matrix size on image quality. Methods: Normal-dose and low-dose bilateral temporal bone CT scans were performed on twelve adult male cadaveric skull specimens using the 160-slice multi-detector CT scanning of United Imaging Healthcare. Normal-dose CT images were reconstructed with matrix sizes of 512×512 and 1 024×1 024, while low-dose CT images were reconstructed with the matrix size of 1 024×1 024. CT value, noise, signal-to-noise ratio, contrast-to-noise ratio, the visualization scoring of 15 anatomical structures of the temporal bone, and the result of three-dimensional reconstruction of the ossicular chain were compared among the three groups. Results: The radiation dose of low-dose CT scanning was reduced by about 50% compared with that of normal-dose CT. There was no significant difference in CT values of air, soft tissues and bones among the three groups. Low-dose temporal bone CT with the matrix size of 1 024×1 024 had higher noise, but much better visualization of temporal bone structure than the normal-dose temporal bone CT with matrix size of 512×512. Both the three-dimensional reconstructions of normal-dose and low-dose 1 024×1 024 matrix images were satisfactory and showed no significant difference. The morphology, size and relative position of malleus, incus, stapes, cochlea, and labyrinth, as well as the location of the ossicular chain in the cranium were all clearly displayed. Conclusion: Low-dose temporal bone CT with the matrix size of 1 024×1 024 can be used to effectively reduce the radiation dose and significantly improve the spatial resolution and the visualization of the temporal bone anatomical structures compared with the normal-dose temporal bone CT with a matrix size of 512×512.


Assuntos
Osso Temporal , Tomografia Computadorizada por Raios X , Adulto , Estudos de Viabilidade , Humanos , Masculino , Imagens de Fantasmas , Doses de Radiação , Razão Sinal-Ruído , Osso Temporal/diagnóstico por imagem
4.
Anal Chem ; 93(39): 13334-13341, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34553919

RESUMO

Herein, a versatile ECL biosensor was fabricated for ultrasensitive detection of microRNA-21 (miRNA-21) from cancer cells based on a novel H2O2-free electrochemiluminescence (ECL) system (luminol/dissolved oxygen/Fe@Fe2O3 nanowires). Compared with the previously reported coreaction accelerator that needed a negative potential to produce reactive oxygen species (ROS), these newly discovered Fe@Fe2O3 nanowires could generate ROS in the detection solution immediately without the application of voltage, which narrowed down the detection potential range to avoid side reactions, favoring their practical application in biological systems. Especially, the Fe@Fe2O3 nanowires could produce H• for activating dissolved oxygen into ROS to improve the ECL intensity dramatically, which initiates a novel pathway to promote the generation of ROS for the ECL system. In addition, an original strand displacement amplification coupled with strand displacement reaction (SDA-SDR) was developed to improve the conversion efficiency of the target for sensitive detection of miRNA-21. By virtue of the SDR, a quadruple quenching effect was achieved through each output DNA strand of SDA; hence, the nucleic acid signal amplification efficiency was effectively enhanced. As expected, on account of the superb activation performance of Fe@Fe2O3 nanowires and the outstanding amplification efficiency of the SDR-SDA strategy, the fabricated ECL biosensor realized ultrasensitive detection of miRNA-21 with a detection limit down to 52.5 aM. The established ECL sensing platform ushered a new route for H2O2-free detection and a promising biomarker assay method for clinical diagnosis.


Assuntos
MicroRNAs , Nanofios , Luminol , Oxigênio
5.
Front Pharmacol ; 12: 715176, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335277

RESUMO

Abuse of methamphetamine (METH), an illicit psychostimulant, is a growing public health issue. METH abuse during pregnancy is on the rise due to its stimulant, anorectic, and hallucinogenic properties. METH can lead to multiple organ toxicity in adults, including neurotoxicity, cardiovascular toxicity, and hepatotoxicity. It can also cross the placental barrier and have long-lasting effects on the fetus. This review summarizes neurotoxicity, cardiovascular toxicity, hepatotoxicity, toxicity in other organs, and biomonitoring of prenatal METH exposure, as well as the possible emergence of sensitization associated with METH. We proposed the importance of gut microbiota in studying prenatal METH exposure. There is rising evidence of the adverse effects of METH exposure during pregnancy, which are of significant concern.

6.
Front Pharmacol ; 12: 716703, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381368

RESUMO

Methamphetamine (METH) is a major psychostimulant drug of abuse worldwide, and its neurotoxicity has been studied extensively. In addition to neurotoxicity, METH can also induce hepatotoxicity. The underlying mechanism of intestinal microorganisms in METH-induced hepatotoxicity remains unclear. In this study, mice have received antibiotics intragastrically or PBS once each day for 1 week, followed by METH or saline. The antibiotics attenuated METH-induced hepatotoxicity as evidenced by histopathological observation and biochemical analysis; furthermore, they alleviated METH-induced oxidative stress. The effect of antibiotics on METH-induced hepatotoxicity was investigated using RNA-sequencing (RNA-seq). The RNA-seq results demonstrated that antibiotics could regulate 580 differentially expressed genes (DEGs), of which 319 were upregulated after METH treatment and then downregulated with antibiotic pretreatment and 237 were first downregulated after METH administration and then upregulated after antibiotic pretreatment, in addition to 11 upregulated and 13 downregulated ones simultaneously in METH and antibiotic-pretreated groups. RNA-seq analyses revealed that TLR4 is one of the hub genes. Western blot analysis indicated that antibiotics inhibited the increase of TLR4, MyD88 and Traf6 induced by METH. This research suggests that antibiotics may play an important role in preventing METH-induced liver injury by regulating oxidative stress and TLR4/MyD88/Traf6 axis, though further investigation is required.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 262: 120117, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34245969

RESUMO

In this paper, a simple, rapid, and low-cost colorimetric method was designed based on Co/Fe-MOFs-iodide composite for the quantitative detection of H2S. It is know that iodide can improve the catalytic activity of bimetallic porous material Co/Fe-MOFs via adsorption into the framework of MOFs. Herein, we demonstrate a novel strategy to enhance the peroxidase-like activity of MOFs. Compared to horseradish peroxidase (HRP), the kinetic measurement results show that Co/Fe-MOFs-iodide exhibits excellent affinity to substrates, promoting electron transfer. Due to the synergetic effect of Co/Fe-MOFs and iodide, and rapid electron transfer process, Co/Fe-MOFs-iodide demonstrates improved peroxidase-like activity. As a proof-of-concept application, a novel, highly sensitive H2S colorimetric method is established with a detection limit (LOD) of 0.33 nM. In the absence of iodide, LOD is approx. 200-fold higher than that of the amplified colorimetric assay. The proposed method can also accurately detect traces of H2S in serum samples.


Assuntos
Colorimetria , Iodetos , Adsorção , Oxirredução
8.
Psychol Serv ; 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34292006

RESUMO

Despite high rates of mental health challenges, Asian Americans are less likely to seek out and receive school-based mental health services (SBMHSs) than their non-Asian peers. The Youth Mental Health First Aid (YMHFA) training is an 8-hr manualized public education program designed to educate adults on recognizing common mental health challenges among adolescents and intervening. However, no published research has evaluated YMHFA among Asian Americans. We culturally adapted YMHFA for Asian Americans (Asian American parents and youth workers) and used a pretest/posttest design to evaluate its effectiveness. Specifically, we (a) added one 2-hr session before the YMHFA to augment engagement with the curriculum and (b) contextualized the YMHFA curriculum content to ensure cultural sensitivity for Asian American participants. Thirty-one Asian immigrant parents (Mage = 45.55, SD = 3.6) and 24 Asian American youth workers (Mage = 23.17, SD = 3.67) participated in YMHFA. Participants' mental health literacy (MHL) and their confidence in using MHFA skills significantly increased after the training. Participants also participated in four focus groups after the training to share their experiences. Participants stated that they benefited from this training and suggested additional cultural adaptations to make the program more appropriate for Asian Americans. Culturally adapted YMHFA may be an effective way to promote MHL and engage Asian Americans in mental health services. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

9.
Anal Chem ; 93(31): 10890-10897, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34313108

RESUMO

Organic materials with diverse structures and brilliant glowing colors have been attracting extensive attention in optical electronic devices and electrochemiluminescence (ECL) fields and are currently faced with the issue of low ECL efficiency. Herein, a series of tetraphenyl alkene nanocrystals (TPA NCs) with an ordered molecular structure were synthesized to explore regularities in the crystallization-induced enhanced (CIE) ECL emission effects by altering the number and position of vinyl on the backbone of TPA molecules. Among those TPA NCs, tetraphenyl-1,3-butadiene (TPB) NCs exhibit the brightest ECL emission via a coreactant pathway, with the relative ECL efficiency of up to 31.53% versus the standard [Ru(bpy)3]2+/TEA system, which is thousands of times higher than that of free TPB molecules. The high ECL efficiency of TPB NCs originates from the effective electron transfer of unique J-aggregates on the a axis of the nanocrystals to notably promote radiative transition and the restriction on the free rotation of TPB molecules to further suppress the nonradiative transition, which has exhibited great potential in ultrasensitive biosensing, efficient light-emitting devices, and clear ECL imaging fields. As a proof of concept, since dopamine (DA) can form benzoquinone species by electrochemical oxidation to realize intermediate radical quenching and excited-state quenching on the TPB NCs/TEA system, the TPB NCs with the CIE ECL effect are used to construct an ultrasensitive ECL-sensing platform for the determination of DA with a lower detection limit of 3.1 nM.


Assuntos
Técnicas Biossensoriais , Nanopartículas , Alcenos , Cristalização , Técnicas Eletroquímicas , Medições Luminescentes
10.
Mikrochim Acta ; 188(8): 266, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34291388

RESUMO

An ultrasensitive electrochemical sensor has been constructed for the detection of single nucleotide polymorphisms (SNPs) based on DNA-functionalized Cd-MOFs-74 as cascade signal amplification probe under enzyme-free conditions. Interestingly, the introduction of an auxiliary probe did not disturb the detection of SNP targets, but could bind more Cd-MOFs-74 signal elements to enhance the different pulse voltammetry electrochemical signal 2~3 times as compared to sensing system without auxiliary probe, which obviously improves the sensitivity of the proposed sensor. Experimental results taking p53 tumor suppressor gene as SNP model demonstrated that the proposed method can be employed to sensitively and selectively detect target p53 gene fragment with a linear response ranging from 0.01 to 30 pmol/L (detection limit of 6.3 fmol/L) under enzyme-free conditions. Utilizing this strategy, the ultrasensitive SNP electrochemical sensor is a promising tool for the determination  of SNPs in biomedicine. Graphical Abstract.

11.
J Mol Cell Biol ; 13(7): 480-499, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34289049

RESUMO

Obesity has reached epidemic proportions globally. Although modern adoption of a sedentary lifestyle coupled with energy-dense nutrition is considered to be the main cause of obesity epidemic, genetic preposition contributes significantly to the imbalanced energy metabolism in obesity. However, the variants of genetic loci identified from large-scale genetic studies do not appear to fully explain the rapid increase in obesity epidemic in the last four to five decades. Recent advancements of next-generation sequencing technologies and studies of tissue-specific effects of epigenetic factors in metabolic organs have significantly advanced our understanding of epigenetic regulation of energy metabolism in obesity. The epigenome, including DNA methylation, histone modifications, and RNA-mediated processes, is characterized as mitotically or meiotically heritable changes in gene function without alteration of DNA sequence. Importantly, epigenetic modifications are reversible. Therefore, comprehensively understanding the landscape of epigenetic regulation of energy metabolism could unravel novel molecular targets for obesity treatment. In this review, we summarize the current knowledge on the roles of DNA methylation, histone modifications such as methylation and acetylation, and RNA-mediated processes in regulating energy metabolism. We also discuss the effects of lifestyle modifications and therapeutic agents on epigenetic regulation of energy metabolism in obesity.

12.
Front Pharmacol ; 12: 641917, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679421

RESUMO

Misuse of the psychostimulant methamphetamine (METH) could induce serious hepatotoxicity. Our previous study revealed the effects of luteolin on alleviating METH-induced hepatotoxicity, however, the detailed mechanisms have not been elucidated. In this study, rats were orally pretreated with 100 mg/kg luteolin or sodium dodecyl sulfate water, and then METH (15 mg/kg, intraperitoneal [i.p.]) or saline was administered. Histopathological and biochemical analyses were used to determine the alleviative effects of luteolin. Based on the RNA-sequencing data, METH induced 1859 differentially expressed genes (DEGs) in comparison with the control group, which were enriched into 11 signaling pathways. Among these DEGs, 497 DEGs could be regulated through luteolin treatment and enriched into 16 pathways. The p53 signaling pathway was enriched in both METH administered and luteolin pretreated rats. Meanwhile, luteolin significantly suppressed METH-induced elevation of p53, caspase9, caspase3, cleaved caspase3, the ratio of Bax/Beclin-2, as well as autophagy-related Beclin-1, Atg5, and LC3-II. Luteolin also relieved METH-induced hepatotoxicity by decreasing inflammation factors, including TNF-α, IL-1ß, and IL-18. Moreover, the levels of PI3K, p-Akt, and the normalized ratio of p-Akt/Akt declined after METH administration, whereas luteolin pretreatment failed to reverse these effects. Our results suggest that luteolin alleviates METH-induced hepatic apoptosis, autophagy, and inflammation through repressing the p53 pathway. It further illustrates the protective mechanisms of luteolin on METH-induced hepatotoxicity and provides a research basis for clinical treatment.

13.
Mol Med Rep ; 23(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33786614

RESUMO

Cervical cancer is a common public health issue with high morbidity worldwide. Paeonol (Pae) has been recognized as a traditional Chinese medicine used for the treatment of various cancer types. However, whether Pae could exert a protective effect on cervical cancer remains to be investigated. The aim of the present study was to explore the role of Pae in cervical cancer cells and identify the potential mechanism. Cell Counting Kit­8 and colony­formation assays were conducted to test the proliferation of HeLa cells. Additionally, wound healing and transwell assays were used to detect the migratory and invasive abilities of cells. The plasmid that overexpressed 5­lipoxygenase (5­LO) or control vector was constructed and transfected into the cells. Subsequently, flow cytometry was used to monitor the apoptotic rate of cells. The expression levels of apoptosis­associated proteins and 5­LO were detected using western blot analysis. Reverse transcription­quantitative PCR analysis detected the expression of 5­LO. Pae inhibited the proliferation, invasion and migration of HeLa cells, promoted cell apoptosis and downregulated the expression of 5­LO. Overexpression of 5­LO, however, attenuated these effects. Thus, Pae could inhibit the proliferation, migration and invasion, as well as promote apoptosis of HeLa cells by regulating the expression of 5­LO.


Assuntos
Acetofenonas/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Araquidonato 5-Lipoxigenase/metabolismo , Movimento Celular/efeitos dos fármacos , Araquidonato 5-Lipoxigenase/genética , Proliferação de Células/efeitos dos fármacos , Células HeLa , Humanos
14.
Food Chem Toxicol ; 148: 111946, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33359793

RESUMO

Methamphetamine (METH) is an addictive and illegal psychostimulant drug that can cause multiple organ dysfunction, especially in the central nervous system (CNS). Gut microbiota have been implicated in development of various CNS-related diseases, via the gut-brain axis (GBA). However, effect of METH in the alteration of gut microbiota and fecal metabolites is unclear, whereas the relationship with METH-induced neurotoxicity remains unknown. In the current study, we investigated effect of METH on neurotoxicity in striatum and colonic damage by exposing BALB/c mice to an escalating dose-multiple binge regimen, and then analyzed protein expression using Western blot analysis. We further detected and sequenced the 16 S rRNA gene in fecal samples, and performed ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS)-based metabolomics to analyze gut microbes and fecal metabolites. Exposure to METH significantly downregulated tyrosine hydroxylase (TH) proteins, but upregulated MAOA, Beclin1, Atg5, and LC3-Ⅱ. METH up-regulated inflammation-related factors, such as caspase1, TNF-α and IL-18, by activating the toll-like receptors 4 (TLR4)/myeloid differentiation factor 88 (Myd88)/nuclear factor κB (NF-κB) pathway and reduced occludin protein expression. In addition, METH exposure changed α and ß diversities of gut microbiota. Specifically, METH exposure elevated relative abundances of pathogenic bacteria, but reduced those of probiotics. Metabolomics, combined with enrichment analyses revealed that METH exposure altered fecal metabolites. Our findings suggest that METH exposure induced autophagy in the CNS, elevated intestinal autophagy flora, leading to accumulation of fecal metabolites in the autophagy pathway, and causing enteritis. Moreover, METH promoted intestinal inflammation by increasing the relative abundance of the pathogenic bacteria in the intestinal tract, and reduced intestinal TJ protein expression.


Assuntos
Estimulantes do Sistema Nervoso Central/toxicidade , Fezes/química , Microbioma Gastrointestinal/efeitos dos fármacos , Metanfetamina/toxicidade , Síndromes Neurotóxicas/etiologia , Animais , Autofagia/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Enterite/induzido quimicamente , Enterite/metabolismo , Masculino , Metabolômica , Camundongos Endogâmicos BALB C , Monoaminoxidase/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Síndromes Neurotóxicas/metabolismo , Ocludina/metabolismo , Receptor 4 Toll-Like/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Regulação para Cima/efeitos dos fármacos
15.
J Cardiovasc Nurs ; 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33027135

RESUMO

BACKGROUND: The theory of planned behavior (TPB), combined with social support, forms the extended TPB, which has shown to predict adherence to health-related behavior effectively, but few studies have applied it to explain medication adherence in patients with coronary heart disease (CHD) after percutaneous coronary intervention (PCI). OBJECTIVES: The aim of this study was to explore the factors associated with medication adherence and the underlying mechanisms based on the extended TPB among patients with CHD after PCI. METHODS: A cross-sectional descriptive study was conducted among patients with CHD after PCI in 2 major hospitals in Guangzhou, China. Medication adherence was measured with the Medication Adherence Report Scale. Constructs of the TPB contributing to medication adherence were assessed by the Theory of Planned Behavior Questionnaire for Medication Adherence. Social support was measured by the Multidimensional Scale of Perceived Social Support. Structural equation modeling was used to examine the hypotheses based on the extended TPB. RESULTS: A total of 300 patients were surveyed and 26.0% of them were nonadherent. The structural equation modeling had good fit indices and estimated 62.6% of the variance in medication adherence. Regarding the relationships between the extended TPB constructs and medication adherence, "intention" was directly associated with medication adherence, and "perceived behavioral control" positively predicted medication adherence directly and indirectly. "Affective attitude" and "subjective norm" were indirectly associated with medication adherence through "intention." Social support exerted an indirect effect on medication adherence through "subjective norm." CONCLUSIONS: The extended TPB is an appropriate model to predict medication adherence and provides an effective framework for adherence-enhancing interventions.

16.
Anal Chem ; 92(21): 14723-14729, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33054154

RESUMO

Herein, the boron radical active sites of boron carbon oxynitride quantum dots (BCNO QDs) are electrically excited to produce boron radicals (B•) for catalyzing peroxydisulfate (S2O82-) as a coreactant to accelerate the generation of abundant sulfate radicals (SO4•-) for significant enhancement in the electrochemiluminescence (ECL) efficiency of BCNO QDs, which overcome the defect of traditional carbon-based QDs with low ECL efficiency. Impressively, under extremely low concentration of S2O82- solution, the BCNO QDs/S2O82- system could exhibit high ECL emission, realizing environmental friendliness and excellent biocompatibility for sensitive bioanalysis. As a proof-of-concept, BCNO QDs, a new generation of ECL emitters with high ECL efficiency, were successfully used in the ultrasensitive determination of microRNA-21, which pushes the exploration of new ECL emitters and broadens the application in the field of clinical diagnosis, ECL imaging, and molecular devices.


Assuntos
Compostos de Boro/química , Limite de Detecção , Medições Luminescentes/métodos , MicroRNAs/análise , Pontos Quânticos/química , Catálise , Eletroquímica , MicroRNAs/química
17.
Org Lett ; 22(18): 7369-7372, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32886516

RESUMO

We report herein an unprecedented protocol for radical cyclization of aldehydes with pendant alkenes via synergistic photoredox, cobaloxime, and amine catalysis. The transformation was achieved in the absence of external oxidants, providing a variety of 5-, 6-, and 7-membered ring products with alkene transposition in satisfactory yields. The reaction exhibits wide functional group compatibility and occurs under mild conditions with extrusion of H2.

18.
New Dir Child Adolesc Dev ; 2020(170): 69-92, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32431073

RESUMO

Research by Xinyin Chen and others has documented that in past decades, shyness in Chinese children was associated with leadership, peer-acceptance, and academic achievement. In contemporary China, shyness predicts maladaptive youth outcomes. Although social, political, and economic transitions are presumed to be responsible for this shift, little is known about how societal change mediates parents' beliefs and the socialization of shy children. This qualitative study explored implicit parenting cognitions and attitudes about shyness in a Chinese urban middle-class group of mothers (N = 20). Thematic analyses revealed mothers' beliefs about the role of family socialization in the development/maintenance of shyness and the complexities between shyness and introversion. Mothers spoke of increased use of child-centered parenting practices and the promotion of assertive and self-assured traits. These findings highlight how Chinese parenting has contributed to the decline in the adaptive value of shyness, and inform the development of parenting interventions for shy Chinese children.


Assuntos
Adaptação Psicológica , Mães , Poder Familiar/etnologia , Personalidade , Timidez , Mudança Social , Socialização , Adaptação Psicológica/fisiologia , Adulto , Criança , Pré-Escolar , China/etnologia , Feminino , Humanos , Introversão Psicológica , Masculino , Personalidade/fisiologia , Pesquisa Qualitativa , Classe Social , População Urbana
20.
Nat Plants ; 6(4): 360-367, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32231254

RESUMO

Temperature-sensitive genic male sterility (TGMS) lines are widely used in the breeding of hybrid crops1,2, but by what means temperature as a general environmental factor reverses the fertility of different TGMS lines remains unknown. Here, we identified an Arabidopsis TGMS line named reversible male sterile (rvms) that is fertile at low temperature (17 °C) and encodes a GDSL lipase. Cytological observations and statistical analysis showed that low temperature slows pollen development. Further screening of restorers of rvms, as well as crossing with a slow-growth line at normal temperature (24 °C), demonstrate that slowing of development overcomes the defects of rvms microspores and allows them to develop into functional pollen. Several other Arabidopsis TGMS lines were identified, and their fertility was also restored by slowing of development. Given that male reproductive development is conserved3, we propose that slowing of development is a general mechanism applicable to the sterility-fertility conversion of TGMS lines from different plant species.


Assuntos
Arabidopsis/fisiologia , Termotolerância , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/ultraestrutura , Temperatura Baixa , Fertilidade/genética , Perfilação da Expressão Gênica , Interação Gene-Ambiente , Genes de Plantas , Mutação , Desenvolvimento Vegetal/genética , Desenvolvimento Vegetal/fisiologia , Pólen/genética , Pólen/crescimento & desenvolvimento , Termotolerância/genética
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