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1.
Chemistry ; 30(17): e202303594, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38278765

RESUMO

Graphene aerogel (GA) has important application potential as piezoresistive sensors due to its low density, high conductivity, high porosity, and good mechanical properties. However, the fabrication of GA-based sensors with good mechanical properties and excellent sensing performance is still challenging. Herein, liquid- metal-modified GAs (GA/LM) are proposed for the development of an excellent GA-based sensor. GA/LM with three-dimensional interconnected layered structure exhibits excellent compressive stress of 41 KPa and fast response time (<20 ms). While generally flexible GA composites cannot be compressed beyond 80 % strain without plastic deformation, GA/LM demonstrates a high compressive strength of 60 kPa under a strain of 90 %. A real-time pressure sensor was fabricated based on GA/LM-2 to monitor swallowing, pulse beating, finger, wrist and knee bending, and even plantar pressure during walking. These excellent features enable potential applications in health detection.

2.
Phys Chem Chem Phys ; 26(7): 5773-5777, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38314869

RESUMO

CO-stripping experiments are employed as a highly structure-sensitive and in situ strategy to explore the mechanisms of plasmon-enhanced electrooxidation reactions. By using Pt-Au heterodimers as a model catalyst, the plasmon-induced current and potential changes on Pt and Au sites can be identified and explained.

3.
Oral Dis ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515263

RESUMO

OBJECTIVES: To search for pathogenic gene of a family with non-syndromic tooth agenesis, and explore the possible pathogenesis. MATERIALS AND METHODS: A Chinese family with non-syndromic tooth agenesis was recruited and screened for the pathogenic variants by whole exome sequencing technology and co-segregation analysis. The subcellular localization of wild-type and mutant protein was detected by immunofluorescence assay. Cycloheximide chase assay was performed to examine the difference in degradation rate between mutant protein and wild-type one. Dual-luciferase reporter assays were conducted to explore the alterations of mutant protein in the regulation of downstream target genes. RESULTS: A novel missense variant of PAX9 (c.296C>A:p.A99D) was found in this family. Bioinformatics software showed ß-return and the random coil were shortened in the p.A99D. The variant did not affect the subcellular localization of PAX9, but the degradation rate of p.A99D was accelerated (p < 0.05). p.A99D inhibited the activation of downstream target gene BMP4 (p < 0.05). CONCLUSIONS: This novel variant expands the pathogenic gene spectrum. The variant impaired the protein structure, accelerated the degradation of protein, and inhibited the activation of the downstream target gene BMP4, an upstream molecule in the TGF-ß/BMP pathway, which may contribute to tooth agenesis in this family.

4.
J Acoust Soc Am ; 155(5): 3380-3393, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38775635

RESUMO

An efficient and precise time-frequency analysis method for real-time ocean bottom seismometer (RTOBS) data in the South China Sea (SCS) is presented. Overcoming the limitations of conventional methods, the method involves temporal segmentation, unique frequency octaves, and Fourier transforms to generate power spectral density (PSD) and probability density function profiles. The method demonstrates superior precision, computational efficiency, and full-bandwidth (0 to Nyquist) capability compared to traditional techniques, as validated through theoretical and empirical evaluations. Applied to SCS RTOBS data, it unveils temporal PSD variations, shedding light on underwater noise sources like earthquakes, offshore blasting, ship-induced disturbances, and tidal effects. Establishing background noise levels in the SCS supports noise source categorization and ocean environment monitoring. Furthermore, comparing onshore and offshore seismic stations advances interdisciplinary research, fostering a comprehensive understanding of acoustics and seismology in the region.

5.
Nano Lett ; 23(17): 8233-8240, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37589668

RESUMO

Surface roughness in chiral plasmonic nanostructures generates asymmetrical localized electromagnetic fields, which hold great promise for applications in chiral recognition, chiroptical spectroscopic sensing, and enantioselective photocatalysis. In this study, we develop a surface topographical engineering approach to precisely manipulate the surface structures of chiral Au nanocrystals. Through carefully controlling the amounts of l- or d-cystine (Cys) and the seed solution in the growth process, we successfully synthesize chiral Au nanocrystals with highly disordered, ordered, and less ordered wrinkled surfaces. An underlying principle governing the relationship between surface roughness, orderliness, and chiroptical response is also proposed. More importantly, the chiral ordered wrinkles on the surfaces of the nanocrystals generate asymmetrical localized electronic fields with enhanced intensity, which achieve excellent plasmon-enhanced chiral discrimination ability for penicillamine (Pen) enantiomers. This work offers exciting prospects for manipulating the surface structures of chiral nanocrystals and designing highly sensitive plasmon-enhanced enantioselective sensors with chiral hot spots.

6.
Chemphyschem ; 24(15): e202200881, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37093151

RESUMO

Metallic heterogeneous nanostructures with plasmonic functionality have attracted great attention in the field of plasmon-enhanced electrocatalysis, where surface plasmons produced under light excitation could facilitate the overall electrocatalytic performances. Owing to their controllability, multifunctionality, and complexity, heterogeneous metallic nanostructures take advantages of the properties from individual components and synergistic effects from adjacent components, thus may achieve remarkable electrocatalytic performances. This review highlights the state-of-the-art progress of the application of metallic heterostructures for plasmon-enhanced electrocatalysis. First, a brief introduction to plasmonic heterogeneous nanostructures is demonstrated. Then, fundamental principles of localized surface plasmon resonance and the underlying mechanisms of plasmonic heterogeneous nanostructures in catalysis are discussed. This is followed by a discussion of recent advances of plasmonic heterogeneous nanostructures in plasmon-enhanced electrocatalysis, in which the enhanced activity, selectivity, and stability are particularly emphasized. Finally, an outlook of remaining challenges and future opportunities for plasmonic heterogeneous nanomaterials and plasmon-related electrocatalysis is presented.

7.
Clin Transplant ; 37(9): e14999, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37115009

RESUMO

BACKGROUND: Ultrasound (US) is the primary imaging modality for the assessment of transplanted kidneys. This study aims to investigate the ability of conventional US and contrast-enhanced US (CEUS) in assessing renal allograft function and prognosis. METHODS: A total of 78 consecutive renal allograft recipients were enrolled. Patients were classified as normal allograft function (n = 41) and allograft dysfunction (n = 37) groups. All patients underwent US and parameters were measured. The independent-samples t-test or Mann-Whitney U test, logistic regression analysis, Kaplan-Meier survival plots, and Cox regression analysis were used. RESULTS: In multivariable analysis, cortical echo intensity (EI) and cortical peak intensity (PI) were determinant US parameters for renal allograft dysfunction (p = .024 and p = .003, respectively). The combination of cortical EI and PI showed an area under the receiver operating characteristic curve (AUROC) of .785 (p < .001). Of 78 patients (median follow-up: 20mo), 16 (20.5%) exhibited composite end points. Cortical PI had a general prediction accuracy with an AUROC of .691, sensitivity of 87.5%, and specificity of 46.8% at the threshold of 22.08 dB in predicting prognosis (p = .019). The combination of estimated-glomerular filtration rate (e-GFR) and PI in predicting prognosis showed an AUROC of .845 with a cut-off value of .836, sensitivity of 84.0%, and specificity of 67.3% (p < .001). CONCLUSION: This study indicates that cortical EI and PI are useful US parameters for evaluating renal allograft function and e-GFR combined with PI may provide a more accurate predictor of survival.


Assuntos
Transplante de Rim , Humanos , Transplante de Rim/efeitos adversos , Rim , Ultrassonografia/métodos , Prognóstico , Aloenxertos
8.
BMC Psychiatry ; 23(1): 322, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37161436

RESUMO

BACKGROUND: Both internet addiction (IA) and non-suicidal self-injury (NSSI) are major public health concerns among adolescents, however, the association between IA and NSSI was not well understood. We aimed to investigate the association between IA and NSSI within a cohort study, and explore the mediated effect of depressive symptoms and the moderating effect of social support in the association. METHODS: A total of 1530 adolescents aged 11-14 years who completed both the baseline (T1) and 14-month follow-up (T2) survey of the Chinese Adolescent Health Growth Cohort were included for the current analysis. IA, NSSI, depressive symptoms and social support were measured at T1; depressive symptoms and NSSI were measured again at T2. Structural equation models were employed to estimate the mediated effect of depressive symptoms and the moderating effect of social support in the association between IA and NSSI at T2. RESULTS: IA was independently associated with an increased risk of NSSI at T2, with the total effect of 0.113 (95%CI 0.055-0.174). Depressive symptoms mediated the association between IA and NSSI at T2, and social support moderated the indirect but not the direct effect of IA on NSSI at T2. Sex differences were found on the mediated effect of depressive symptoms and the moderated mediation effect of social support. CONCLUSIONS: Interventions that target adolescents' NSSI who also struggle with IA may need to focus on reducing depressive symptoms and elevating social support.


Assuntos
Transtorno de Adição à Internet , Comportamento Autodestrutivo , Humanos , Adolescente , Feminino , Masculino , Estudos de Coortes , Depressão/complicações , China , Apoio Social
9.
BMC Med Imaging ; 23(1): 216, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129778

RESUMO

BACKGROUND: Due to the highly heterogeneity of the breast cancer, it would be desirable to obtain a non-invasive method to early predict the treatment response and survival outcome of the locally advanced breast cancer (LABC) patients undergoing neoadjuvant chemotherapy (NAC). This study aimed at investigating whether strain elastography (SE) can early predict the pathologic complete response (pCR) and recurrence-free survival (RFS) in LABC patients receiving NAC. METHODS: In this single-center retrospective study, 122 consecutive women with LABC who underwent SE examination pre-NAC and after one and two cycles of NAC enrolled in the SHPD001(NCT02199418) and SHPD002 (NCT02221999) trials between January 2014 and August 2017 were included. The SE parameters (Elasticity score, ES; Strain ratio, SR; Hardness percentage, HP, and Area ratio, AR) before and during NAC were assessed. The relative changes in SE parameters after one and two cycles of NAC were describe as ΔA1 and ΔA2, respectively. Logistic regression analysis and Cox proportional hazards model were used to identify independent variables associated with pCR and RFS. RESULTS: Forty-nine (40.2%) of the 122 patients experienced pCR. After 2 cycles of NAC, SR2 (odds ratio [OR], 1.502; P = 0.003) and ΔSR2 (OR, 0.013; P = 0.015) were independently associated with pCR, and the area under the receiver operating characteristic curve for the combination of them to predict pCR was 0.855 (95%CI: 0.779, 0.912). Eighteen (14.8%) recurrences developed at a median follow-up of 60.7 months. A higher clinical T stage (hazard ratio [HR] = 4.165; P = 0.005.), a higher SR (HR = 1.114; P = 0.002.) and AR (HR = 1.064; P <  0.001.) values at pre-NAC SE imaging were independently associated with poorer RFS. CONCLUSION: SE imaging features have the potential to early predict pCR and RFS in LABC patients undergoing NAC, and then may offer valuable predictive information to guide personalized treatment.


Assuntos
Neoplasias da Mama , Técnicas de Imagem por Elasticidade , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Terapia Neoadjuvante , Ultrassom , Estudos Retrospectivos
10.
Lett Appl Microbiol ; 76(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37204034

RESUMO

Here we aim to build up a metagenomics-centered surveillance on the infectious microbiome showing in the fever of unknown origin (FUO) patients. We collected venous blood, bronchoalveolar lavage fluid, cerebrospinal fluid, tissue block, sputum, bone marrow biopsy, and purulent liquid samples from 123 patients. Metagenomic sequencing (mNGS) for both DNA and RNA sequences was performed to profile the total pathogenic microbiome in the samples. A large pool of infectious or conditional infectious bacteria was found, belonging to Enterobacteriaceae, Staphylococcaceae (10.55%), Burkholderiaceae (10.05%), and Comamonadaceae (4.25%). The major virus families detected from mNGS analysis include Adenoviridae, Anelloviridae, Peribunyaviridae, Flaviviridae, and Herpesviridae, showing up in 34.96%, 47.37%, 30.89%, 5.69%, 3.25%, and 1.63% of patients, respectively. Using the Ward clustering method, two clusters of patients were organized: high-variety group and low-variety group. The patients in the high-variety group demonstrated higher levels of immune cells and inflammatory indicators such as lactate dehydrogenase, aspartate aminotransferase, and alanine aminotransferase. The patients in the low-variety group showed higher levels of inflammatory lipids such as 13,14-dihy-15-keto PGE2 (fold > 10, P = 0.021); tetra-PGDM (fold = 5.29, P = 0.037); and 20-HETE (fold > 10, P = 0.02). The mNGS surveillance system demonstrated remarkable potential in preventing infectious diseases using mNGS data.


Assuntos
Febre de Causa Desconhecida , Microbiota , Humanos , Febre de Causa Desconhecida/diagnóstico , Metagenômica/métodos , Microbiota/genética , Bactérias/genética , Metagenoma , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Sensibilidade e Especificidade
11.
J ECT ; 39(2): 111-116, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36413657

RESUMO

OBJECTIVE: This study aims to provide an evaluation of electroconvulsive therapy (ECT) in hospitalized adolescents with major depressive and bipolar disorders by examining its treatment outcomes as well as comparing it with outcomes of hospitalized patients, treated as usual (TAU). METHODS: This is a retrospective study based on medical records documented between April 2011 and December 2017 from Beijing An Ding Hospital. Patients were diagnosed according to the International Classification of Diseases, Tenth Revision . The study included 288 inpatients, with 2 groups of 171 patients treated by ECT and 117 TAU. The primary outcome was measured using the severity subscale of Clinical Global Impression. Mann-Whitney U test, χ2 test, and linear regression with mixed models were used to analyze the data. RESULTS: Symptom severity reduced significantly for both groups ( ß = -0.62, t975.93 = -20.54, P < 0.001). The TAU group was associated with lower score on the severity subscale of Clinical Global Impression ( ß = 0.28, t980.32 = 8.36, P < 0.001). The ECT group had a higher remission rate (28.65%) than the TAU group (16.24%), but the time required for remission was longer ( U [ NECT = 49, NTAU = 19] = 615, z = 2.10, P = 0.04). Adverse events of ECT were barely observed. CONCLUSION: Electroconvulsive therapy is an efficacious and safe treatment for adolescents. However, as the superiority in efficacy was not evident in ECT group, its prescription should be prudently considered for younger patients who respond well to other treatments.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Eletroconvulsoterapia , Humanos , Adolescente , Eletroconvulsoterapia/efeitos adversos , Transtorno Bipolar/tratamento farmacológico , Transtorno Depressivo Maior/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento
12.
Nano Lett ; 22(7): 2915-2922, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35362992

RESUMO

Metal surfaces with intrinsic chirality play an irreplaceable role in many significant enantioselective chemical processes such as enantioselective catalysis, sensing, and separation. Nonetheless, current methods for the precise preparation of such chiral surfaces suffer with issues of unscalable production and low surface areas. Herein, we report the synthesis of chiral Au nanoparticles with precisely determined homochiral facets. Though a scalable wet chemical method, {125̅8}R and {85̅12}S high-Miller-index facets are obtained with the l- and d-chiral Au nanocrystals, respectively. The growth process of these homochiral facets is investigated, and a new nanocrystal growth pathway is revealed. More importantly, the remarkable enantioselective recognition properties of these homochiral surfaces are demonstrated and enable an efficient electrochemical method for chiral discrimination of l-/d-tryptophan. These results provide a foundation of fundamental studies of heterogeneous enantioselective processes and may pave way for the development of nanocatalysts for enantioselective chemistry.


Assuntos
Ouro , Nanopartículas Metálicas , Catálise , Técnicas Eletroquímicas , Estereoisomerismo , Triptofano
13.
Chemistry ; 28(32): e202200494, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35319121

RESUMO

Surface plasmon of coinage metal nanostructures has been employed as a powerful route in boosting the performances in heterogenous catalysis. Development of efficient plasmonic nanocatalysts with high catalytic performance and efficient light harvesting properties is of vital importance. Herein, we rationally designed and synthesized a plasmonic nanocatalyst composed of Au-framed Pd nanocubes by an Ag(I)-assisted seed-mediated growth method. In the synthesis, the incorporation of Ag(I) suppresses the reduction of Au on the {100} surface of cubic Pd seeds and leads to the formation of Au nanoframes on the Pd nanocubes. The unique Au-framed Pd nanocubes can integrate the superior electrocatalytic of Pd and the outstanding plasmonic properties of Au. Thus, these nanostructures were employed as plasmonic nanocatalysts for plasmon-enhanced electrocatalytic oxidation of ethanol with improved stability.

14.
J Child Psychol Psychiatry ; 63(1): 34-46, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34019305

RESUMO

BACKGROUND: To date, no national-scale psychiatric epidemiological survey for children and adolescents has been conducted in China. In order to inform government officials and policymakers and to develop a comprehensive plan for service providers, there was a clear need to conduct an up-to-date systematic nationwide psychiatric epidemiological survey. METHODS: We conducted a two-stage large-scale psychiatric point prevalence survey. Multistage cluster stratified random sampling was used as the sampling strategy. Five provinces were selected by comprehensively considering geographical partition, economic development, and rural/urban factors. In Stage 1, the Child Behavior Checklist was used as the screening tool. In Stage 2, Mini-International Neuropsychiatric Interview for Children and Adolescents and a diagnostic process based on the Diagnostic and Statistical Manual were used to make the diagnoses. Sampling weights and poststratification weights were employed to match the population distributions. Exploratory analyses were also performed using socio-demographic factors. Prevalence in socio-demographic factor subgroups and overall were estimated. Rao-Scott adjusted chi-square tests were utilized to determine if between-group differences were present. Factor interactions were checked by logistic regression analyses. RESULTS: A total of 73,992 participants aged 6-16 years of age were selected in Stage 1. In Stage 2, 17,524 individuals were screened and diagnosed. The weighted prevalence of any disorder was 17.5% (95% CI: 17.2-18.0). Statistically significant differences in prevalence of any psychiatric disorder were observed between sexes [χ2 (1, N = 71,929) = 223.0, p < .001], age groups [χ2 (1, N = 71,929) = 18.6, p < .001] and developed vs. developing areas [χ2 (1, N = 71,929) = 2,129.6, p < .001], while no difference was found between rural and urban areas [χ2 (1, N = 71,929) = 1.4, p = .239]. Male, younger individuals, children, and adolescents from developed areas had higher prevalence of any psychiatric disorder. The prevalence of any psychiatric disorder was found to decrease with the age in the male group, while the female group increased with the age. Individuals diagnosed with attention-deficit hyperactivity disorder, oppositional defiant disorder, a tic disorder, conduct disorder, and major depression disorder had the highest rates of comorbidity. CONCLUSIONS: The prevalence of any psychiatric disorder we found is the highest ever reported in China. These results urgently need to be addressed by public mental health service providers and policymakers in order to provide access to the necessary treatments and to reduce the long-term negative impact of these conditions on families and the society as a whole.


Assuntos
Transtorno Depressivo Maior , Transtornos Mentais , Adolescente , Transtornos de Deficit da Atenção e do Comportamento Disruptivo , Criança , China/epidemiologia , Comorbidade , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Prevalência
15.
Andrologia ; 54(8): e14484, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35624551

RESUMO

To analyse spermatic vein parameters and post-varicocelectomy diagnostic ultrasound methods by comparing pre- and post-operative ultrasound parameters and semen quality in patients undergoing varicocelectomy. Ultrasound and semen analyses were performed within 1 week before surgery and 3 months after surgery in 125 patients who underwent varicocelectomy for infertility. Patients were divided into three groups according to the post-operative internal diameter of the spermatic vein and reflux: recovery, dilatation, and reflux. Changes in semen quality before and after surgery were compared between groups. Sperm concentration, motility, and morphology were significantly improved (p < 0.05); however, semen volume did not improve (p > 0.05) in patients in the recovery and dilatation groups compared to those in patients before surgery. Sperm concentration, motility, and semen volume did not improve in patients in the reflux group compared with those in patients before surgery (p > 0.05). Logistic regression analysis revealed that the internal diameter of the spermatic vein and reflux duration were risk factors for post-operative spermatic vein dilatation without reflux. Ultrasonography after varicocelectomy should primarily be used to observe reflux, and should not be used as a diagnostic criterion for varicocele based on the internal diameter of the spermatic vein alone.


Assuntos
Infertilidade Masculina , Varicocele , Humanos , Infertilidade Masculina/diagnóstico por imagem , Infertilidade Masculina/etiologia , Infertilidade Masculina/cirurgia , Masculino , Sêmen , Análise do Sêmen , Contagem de Espermatozoides , Varicocele/complicações , Varicocele/diagnóstico por imagem , Varicocele/cirurgia , Veias/diagnóstico por imagem , Veias/cirurgia
16.
Zhongguo Zhong Yao Za Zhi ; 47(1): 62-71, 2022 Jan.
Artigo em Zh | MEDLINE | ID: mdl-35178912

RESUMO

Dof(DNA binding with one finger), a unique class of transcription factors in plants, play an important role in seed development, tissue differentiation, and metabolic regulation. To identify the number and function of Dof gene family members in Panax ginseng, this study identified the members of Dof gene family in P. ginseng and systematically analyzed their structures, evolution, functional differentiation, expression patterns, and interactions using bioinformatics methods at the transcriptome level. At the same time, the association analysis of Dof genes from P. ginseng with key enzyme genes for ginsenoside synthesis was carried out to screen the candidate PgDof genes involved in the regulation of ginsenoside biosynthesis. The results showed that there were 54 genes belonging to the Dof gene family in P. ginseng from Jilin. All PgDof genes had Zf-Dof conserved motifs, implying that they were evolutionarily conserved and could be divided into five groups. Expression pattern analysis confirmed that the expression of PgDof gene family members in different tissues, different year-old P. ginseng, and different farm varieties varied significantly. Simultaneously, as revealed by "gene-saponin content" and "gene-gene" linkage analysis, an important candidate PgDof14-1 gene involved in the regulation of ginsenoside biosynthesis was obtained. From the established genetic transformation system of this gene in the hairy roots of P. ginseng, a positive hairy root clone was determined. This study has laid a theoretical foundation for the study of Dof gene family in P. ginseng.


Assuntos
Ginsenosídeos , Panax , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Transcriptoma
17.
Small ; 17(47): e2104083, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34655154

RESUMO

Nanozymes have offered remarkable advantages over natural enzymes and found widespread applications including biosensors, immunoassays, nanomedicines, and environmental remediation. Oxidation of o-phenylenediamine (OPD) by nanozymes has been listed as a standard protocol for determining nanozyme activities. Given the complexity of OPD oxidation processes, however, the mechanism of nanozyme-catalyzed oxidation of OPD remains elusive. In this report, mechanistic studies of nanozyme-catalyzed oxidation of OPD are performed and a distinguishably different mechanism from that of natural enzymes is found. A combination of Fourier transform infrared spectroscopy, nuclear magnetic resonance, electrospray ionization mass spectrometry, and electron microscopic studies provides compelling evidence that polymerization of OPD occurs on the surface of several different nanozymes. The unexpected polymerization causes a dense coating layer of poly(o-phenylenediamine) (POPD) on nanozymes renders the intrinsic properties of nanozymes. Therefore, this fundamental discovery raise serious concerns using OPD-based colorimetric method for determining nanozyme activities. Without examining the surface change of nanozymes after catalytic reactions, the use of OPD-based colorimetric method for determining nanozyme activities is strongly discouraged. Furthermore, POPD is discovered as a new oxidase mimic, and this new mechanism also provides a general and robust method to coat nanomaterials with POPD polymers of enzyme-mimicking properties.


Assuntos
Colorimetria , Fenilenodiaminas , Catálise , Domínio Catalítico
18.
Gynecol Endocrinol ; 37(4): 337-341, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32851887

RESUMO

AIMS: The effective treatment of polycystic ovary syndrome (PCOS)-related hormonal disorders necessitates the development of novel treatment strategies. Resveratrol is found in certain food products, and is known to exhibit phytoestrogen properties. The present study was to assess whether resveratrol exhibits beneficial phytoestrogenic effects and associated hormonal modulation in a rat model of PCOS. MATERIALS AND METHODS: This model was established by administering oral letrozole to female Sprague-Dawley (SD) rats prior to randomizing them into control, model and resveratrol treatment groups (40, 80, or 160 mg/kg). Animals were treated for 30 days, after which time ovarian tissues were collected and evaluated via hematoxylin and eosin staining. In addition, serum levels of estradiol and adiponectin were assessed via ELISA, and ovarian expression of nesfatin-1 and aromatase was assessed through RT-PCR and western blotting. RESULTS: We found that resveratrol administration was associated with increased levels of plasma adiponectin and estradiol levels and restoration of normal ovarian morphology in PCOS model animals. In addition, this treatment was linked to the increased ovarian expression of nesfatin-1 and aromatase at the RNA and protein levels. CONCLUSIONS: Together things findings suggest that resveratrol may represent an effective tool for treating PCOS owing to its phytoestrogenic properties.


Assuntos
Ovário/efeitos dos fármacos , Fitoestrógenos/farmacologia , Síndrome do Ovário Policístico/patologia , Resveratrol/farmacologia , Adiponectina/metabolismo , Animais , Aromatase/efeitos dos fármacos , Aromatase/genética , Inibidores da Aromatase/toxicidade , Modelos Animais de Doenças , Estradiol/metabolismo , Feminino , Letrozol/toxicidade , Nucleobindinas/efeitos dos fármacos , Nucleobindinas/genética , Ovário/metabolismo , Ovário/patologia , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo , Distribuição Aleatória , Ratos
19.
Eur Child Adolesc Psychiatry ; 30(2): 233-241, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32172341

RESUMO

Improving the mental health of children and adolescents is a critical priority in China. However, only minimal information is available concerning the prevalence of mental disorders. In the present study, a two-stage national survey has been completed in five regions of China. In the first stage, data from the Achenbach Child Behavior Checklist (CBCL) were collected for each participant to identify the prevalence of the behavioral and emotional problems in China. A multistage cluster stratified random sampling design was used, and a total of 71,929 individuals aged 6-16 years were collected. In this large cohort, 36,893 (49.86%) were males, and 49,015 (66.24%) were living in urban communities. Overall, 17.6% (90% confidence interval 17.4%, 17.9%) of the children and adolescents were identified as having behavioral and emotional problems. Moreover, age and sex effect was found for the CBCL scores. The boys' cohort had a higher prevalence of behavioral and emotional problems than girls (18.6% versus 16.6%). In the older cohort aged 12-16, the prevalence was higher than for the younger cohort aged 6-11 (19.0% versus 15.9%). Notably, it seems that the prevalence of the behavioral and emotional problems for children and adolescents had a rise in the past 30 years, but the scarcity of pediatric psychiatrists in China needs to be addressed. To reduce the behavioral and emotional problems, the whole society, including mental health providers, educators, and parents, needs to focus on and pay more attention to it. It will have long-term benefits for China.


Assuntos
Sintomas Afetivos/psicologia , Transtornos do Comportamento Infantil/psicologia , Criança , China , Feminino , Humanos , Masculino , Transtornos Mentais/epidemiologia , Prevalência , Inquéritos e Questionários
20.
J Acoust Soc Am ; 150(4): 2738, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34717473

RESUMO

The acoustic pressure field in many underwater environments is well described by a superposition of normal modes. The normal modes can be used for source localization and environmental inversion. However, the wavenumber resolution of traditional normal mode filtering methods for a small-aperture horizontal array is usually not sufficient to identify individual modes in a shallow water waveguide. This paper proposes an original method of normal mode energy estimation to remove the energy leakage between modes. The modal energy is defined as the square of the modal amplitude. This method is to reconstruct the incoherent beamformed outputs in wavenumber domain for a horizontally moving source. The adaptive beamforming is used to suppress interference and improve output signal-to-noise ratio. The uncertainty of modal phase velocity has also been considered in this method. The proposed method can provide more accurate estimates of modal energy for a small-aperture horizontal array than the traditional mode filtering methods, such as the matched filter, the least squares mode filter, the regularized-least squares mode filter, and the maximum a posteriori mode filter, in simulations and experiments.

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