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Porphyrins-based porous organic polymers were widely used in photocatalytic oxidation under visible light owing to their superiority in the activation of oxygen. In contrast, the efficiency is usually limited due to the fast recombination and slow electron transfer. Herein, we report the use of a trioporphyrins-based covalent triazine framework (Por-CTF) as visible-light-active photocatalyst for the coupling oxidative of amines to imines at room temperature. By incorporating the π-conjugated porphyrin building block led to the enhanced electron transport between molecules, and the extended recombination time of excited electrons. The photocatalytic efficiency of Por-CTF is superior to that of polymer in absence of triazine framework (POP-TSP), which was prepared by radical polymerization using tetra-(4-vinylphenyl) porphyrin as monomer. Por-CTF catalyst presented excellent efficiency for various primary amines and stability. This work provides a reasonable guidance of catalyst molecular structure design for enhancing efficiency in the photocatalytic oxidation.
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Alzheimer's disease (AD) is an intricate neurodegenerative disorder characterized by the accumulation of misfolded proteins, including beta-amyloid (Aß) and tau, leading to cognitive decline. Despite decades of research, the precise mechanisms underlying its onset and progression remain elusive. Cathepsins are a family of lysosomal enzymes that play vital roles in cellular processes, including protein degradation and regulation of immune responses. Emerging evidence suggests that cathepsins may be involved in AD pathogenesis. Cathepsins can influence the activation of microglia and astrocytes, the resident immune cells in the brain. However, cathepsin dysfunction may lead to the accumulation of misfolded proteins, notably Aß and tau. In addition, dysregulated cathepsin activity may induce an exaggerated immune response, promoting chronic inflammation and neuronal dysfunction in patients with AD. By unraveling the classification, functions, and roles of cathepsins in AD's pathogenesis, this review sheds light on their intricate involvement in this devastating disease. Targeting cathepsin activity could be a promising and novel approach for mitigating the pathological processes that contribute to AD, providing new avenues for its treatment and prevention.
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Pluripotent stem cells were generated through the electroporation of episomal plasmids, containing crucial reprogramming factors, into skin fibroblasts extracted from a female Alzheimer's patient harboring the PSEN1 709 T > C (p.Phe237Leu) heterozygous mutation. The pluripotent stem cells exhibit a normal karyotype and express pivotal stem cell markers including TRA-1-60, Nanog, SOX2, and OCT4. Furthermore, their capacity to differentiate into the three germ layers in in vivo teratoma experiments has been substantiated. The pluripotent stem cell line can serve as a cellular model for Alzheimer's disease, offering significant value in elucidating the pathogenesis and therapeutic strategies of the disease.
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Enfermedad de Alzheimer , Heterocigoto , Células Madre Pluripotentes Inducidas , Mutación , Presenilina-1 , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Femenino , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Presenilina-1/genética , Línea Celular , Diferenciación Celular , Fibroblastos/metabolismo , AnimalesRESUMEN
Anaplasma and Ehrlichia are tick-borne bacterial pathogens that cause anaplasmoses and ehrlichioses in humans and animals. In this study, we examined the prevalence of Anaplasma and Ehrlichia species in ticks and domesticated animals in Suizhou County, Hubei Province in the central China. We used PCR amplification and DNA sequencing of the 16S rRNA, groEL, and gltA genes to analyze. We collected 1900 ticks, including 1981 Haemaphysalis longicornis and 9 Rhipicephalus microplus, 159 blood samples of goats (n = 152), cattle (n = 4), and dogs (n = 3) from May to August of 2023. PCR products demonstrated that Anaplasma bovis, Anaplasma capra, and an Ehrlichia species were detected in the H. longicornis with the minimum infection rates (MIR) of 1.11%, 1.32%, and 0.05%, respectively; A. bovis, A. capra, and unnamed Anaplasma sp. were detected in goats with an infection rate of 26.31%, 1.31% and 1.97%, respectively. Anaplasma and Ehrlichia species were not detected from cattle, dogs and R. microplus ticks. The genetic differences in the groEL gene sequences of the Anaplasma in the current study were large, whereas the 16S rRNA and gltA gene sequences were less disparate. This study shows that ticks and goats in Suizhou County, Hubei Province carry multiple Anaplasma species and an Ehrlichia species, with relatively higher infection rate of A. bovis in goats. Our study indicates that multiple Anaplasma and Ehrlichia species exist in ticks and goats in the central China with potential to cause human infection.
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Anaplasma , Anaplasmosis , Animales Domésticos , Ehrlichia , Variación Genética , Cabras , ARN Ribosómico 16S , Animales , Anaplasma/genética , Anaplasma/aislamiento & purificación , China/epidemiología , Ehrlichia/genética , Ehrlichia/aislamiento & purificación , Cabras/microbiología , Perros , Bovinos , Anaplasmosis/epidemiología , Anaplasmosis/microbiología , Prevalencia , Animales Domésticos/microbiología , ARN Ribosómico 16S/genética , Garrapatas/microbiología , Ehrlichiosis/epidemiología , Ehrlichiosis/veterinaria , Ehrlichiosis/microbiología , FilogeniaRESUMEN
Nitrofurans are important synthetic broad-spectrum antibacterial drugs with the basic structure of 5-nitrofuran. Due to their toxicity, it is essential to develop a sensitive sensor with strong anti-interference capabilities for their detection. In this work, two {P4Mo6O31}12--based compounds, [H4(HPTTP)]2{CuI[Mo12O24(OH)6(PO4)3(HPO4)(H2PO4)4]}·xH2O (x = 13 for (1), 7 for (2); HPTTP = 4,4',4â³,4â´-(1H-pyrrole-2,3,4,5-tetrayl)tetrapyridine), exhibiting similar coordination but distinct stacking modes. Both compounds were synthesized and used for the electrochemical detection of nitrofuran antibiotics. The tetrapyridine-based ligand was generated in situ during assembly, and its potential mechanism was discussed. Composite electrode materials, formed by mixing graphite powder with compounds 1-2 and physically grinding them, proved to be highly effective in the electrochemical trace detection of furazolidone (FZD) and furaltadone hydrochloride (FTD·HCl) under optimal conditions. Besides, the possible electrochemical detection mechanisms of two nitro-antibiotics were studied.
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Antibacterianos , Complejos de Coordinación , Cobre , Nitrofuranos , Polímeros , Antibacterianos/química , Antibacterianos/análisis , Ligandos , Nitrofuranos/análisis , Nitrofuranos/química , Cobre/química , Cobre/análisis , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Polímeros/química , Molibdeno/química , Piridinas/química , Estructura Molecular , Técnicas Electroquímicas , Modelos MolecularesRESUMEN
Waste liquid stored in the containment sumps of nuclear power plants may contain a variety of radionuclides. Real-time monitoring of containment sump waste liquid can ensure that accidents, such as leakage of cooling water, can be avoided. This paper presents the design of a radioactive monitoring system for waste liquid in a containment sump. The detector and the lead-shield in the measurement unit are optimized through Monte Carlo simulations. Experimental verification showed that the background count rate of the measurement chamber in the system was 418.3 cps, and the detection limit of the detection system was 3.01 Bq/L. Distinct gamma-ray characteristic peaks were also observable, demonstrating the system's ability to identify radioactive nuclides in the waste.
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An aerobic methanotroph was isolated from a secondary sedimentation tank of a wastewater treatment plant and designated strain OY6T. Cells of OY6T were Gram-stain-negative, pink-pigmented, motile rods and contained an intracytoplasmic membrane structure typical of type I methanotrophs. OY6T could grow at a pH range of 4.5-7.5 (optimum pH 6.5) and at temperatures ranging from 20â°C to 37â°C (optimum 30â°C). The major cellular fatty acids were C14â:â0, C16â:â1ω7c/C16â:â1ω6c and C16â:â1ω5c; the predominant respiratory quinone was MQ-8. The genome size was 5.41 Mbp with a DNA G+C content of 51.7 mol%. OY6T represents a member of the family Methylococcaceae of the class Gammaproteobacteria and displayed 95.74-99.64â% 16S rRNA gene sequence similarity to the type strains of species of the genus Methylomonas. Whole-genome comparisons based on average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH) confirmed that OY6T should be classified as representing a novel species. The most closely related type strain was Methylomonas fluvii EbBT, with 16S rRNA gene sequence similarity, ANI by blast (ANIb), ANI by MUMmer (ANIm) and dDDH values of 99.64, 90.46, 91.92 and 44.5â%, respectively. OY6T possessed genes encoding both the particulate methane monooxygenase enzyme and the soluble methane monooxygenase enzyme. It grew only on methane or methanol as carbon sources. On the basis of phenotypic, genetic and phylogenetic data, strain OY6T represents a novel species within the genus Methylomonas for which the name Methylomonas defluvii sp. nov. is proposed, with strain OY6T (=GDMCC 1.4114T=KCTC 8159T=LMG 33371T) as the type strain.
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Methylococcaceae , Methylomonas , Metano , Filogenia , ARN Ribosómico 16S/genética , Composición de Base , Ácidos Grasos/química , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Bacterias , Methylococcaceae/genética , Oxidación-ReducciónRESUMEN
Microplastics (MPs) transfer from the environment to living organisms is a nonignorable global problem. As a complete metamorphosis insect, the larvae and adult Culex quinquefasciatus mosquito live in aquatic and terrestrial environments, respectively, where they easily access MPs. However, little is known about mosquitoes' potential role in MPs accumulation throughout ecosystems. Therefore, we conducted a study with different MPs particle sizes (0.1/1/10 µm) and concentrations (0.5/5/50 µg/mL) on Cx. quinquefasciatus to address this issue. Once exposed at the young larval stage, MPs could accompany the mosquitoes their entire life. The fluorescence signals of MPs in the larvae were mainly located in the intestines. Its intensity increased (from 3.72 × 106 AU to 5.45 × 107 AU) as the concentrations of MPs increases. The fluorescence signals of MPs were also detected in the blood and skin tissues of mice bitten by adult mosquitoes with MPs containing in their bodies. Mosquitos exposed to MPs showed longer larval pupation and eclosion time as well as lower adult body weight. In addition, MPs significantly reduced the lethal effect of pyrethroid insecticides (97.77 % vs. 48.88 %, p < 0.05) with 15.1 % removal of the deltamethrin concentration. After MPs exposure, the relative abundance of the Cx. quinquefasciatus gut microbiome, such as Wolbachia spp., Elizabethkingia spp., and Asaia spp., changed as the MPs size and concentration changes. Mosquitoes provide a new pathway for MPs accumulation and transfer to higher-level living organisms. Moreover, MPs significantly reduce the control effect of deltamethrin, providing new guidelines for mosquito insecticide application in MPs contamination circumstances.
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Culex , Mordeduras y Picaduras de Insectos , Insecticidas , Nitrilos , Piretrinas , Animales , Ratones , Microplásticos , Plásticos , Ecosistema , Insecticidas/toxicidad , Larva , Mamíferos , Control de MosquitosRESUMEN
Objective: To investigate the association between ß1 adrenergic receptor autoantibodies (ß1-AA) and angiotensin II type-1 receptor autoantibodies (AT1-AA) and cardiac function in patients with hypertension complicated with left ventricular diastolic function limitation. Methods: A total of 120 patients with essential hypertension who were not taking drug treatment and were hospitalised in the Department of Cardiology at the authors' hospital from April 2018 to December 2018 were enrolled in this study and divided into a diastolic dysfunction group (65 cases) and a normal diastolic group (55 cases) according to their left ventricular diastolic function. The levels of cardiac parameters, ß1-AA, AT1-AA, and other indicators were compared. Logistic regression analysis was used to analyse the related factors affecting left ventricular diastolic dysfunction (LVDD). The diagnostic efficacy of related factors in the diagnosis of diastolic dysfunction was evaluated. Results: Univariate analysis demonstrated that the left ventricular posterior wall diameter (10.29 ± 1.23 vs. 9.12 ± 1.53), left ventricular systolic dysfunction (10.56 ± 1.37 vs. 9.43 ± 1.44), systolic blood pressure (152.37 ± 10.24 vs. 140.33 ± 5.99), diastolic blood pressure (95.66 ± 6.34 vs. 87.33 ± 7.28), ß1-AA (33 vs. 9 cases), and AT1-AA (35 cases vs. 12 cases) were higher in the dysfunction group than in the control group (all P < 0.05). Multivariate regression analysis showed that ß1-AA (odds ratio (OR) = 1.96, 95% confidence interval (CI): 1.369-4.345) and AT1-AA (OR = 2.02, 95% CI: 1.332-6.720) were independent risk factors for cardiac diastolic dysfunction (P < 0.05). Both autoimmune antibodies had a certain predictive value, and the combined prediction value of the two was the highest, with an area under the curve of 0.942 (95% CI: 0.881~0.985). Conclusion: The positive rate of ß1-AA and AT1-AA in essential hypertension patients with LVDD was higher than that in the normal group. Both ß1-AA and AT1-AA could be used as early markers of LVDD in essential hypertension patients.
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Cardiomiopatías , Hipertensión , Disfunción Ventricular Izquierda , Humanos , Autoanticuerpos , Hipertensión/complicaciones , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Función Ventricular Izquierda , Disfunción Ventricular Izquierda/diagnóstico , Cardiomiopatías/complicaciones , Hipertensión Esencial/complicaciones , Hipertensión Esencial/diagnósticoRESUMEN
This study aimed to identify glycosylation-related genes associated with lung adenocarcinoma (LUAD) prognosis through comprehensive bioinformatic analysis. Glycosylation-related genes were identified from the Human Gene Nomenclature Committee, and LUAD prognostic genes were screened from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO)-GSE68465 datasets. Glycosylation risk score (GLRS) was calculated to predict LUAD prognostic risk. Samples were grouped into GLRS-high and GLRS-low and compared. The Tumor Immune Dysfunction and Exclusion (TIDE) score was computed to assess the antitumor immune escape possibility after immunotherapy. From 213 glycosylation-related genes, five gene signatures served as prognostic LUAD predictors using univariate and stepwise Cox regression analyses. GLRS-based models were constructed using TCGA and GSE68465 samples; their sensitivity and specificity in predicting LUAD prognosis were confirmed. GLRS was an independent LUAD prognostic factor and contributed to the nomogram to predict patient survival. High GLRS was associated with advanced tumor stage and higher mutation frequencies, estimate scores, and TIDE scores. GLRS-high and GLRS-low patients differed in immune cell infiltration and epithelial-mesenchymal transition (EMT)-related gene expression. Thus, we propose five glycosylation-related gene signatures to predict overall survival and prognostic risks of LUAD. Their regulatory roles may be related to immune invasion, immunotherapy response, mutation, and EMT.
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Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Pronóstico , Glicosilación , Adenocarcinoma del Pulmón/genética , Biología Computacional , Neoplasias Pulmonares/genéticaRESUMEN
Cellular heterogeneity, especially in some important diseased cells like tumor cells, acts as an invisible driver for disease development like cancer progression in the tumor ecosystem, contributing to differences in the macroscopic and microscopic detection of disease lesions like tumors. Traditional analysis techniques choose group information masked by the mean as the analysis sample, making it difficult to achieve precise diagnosis and target treatment, on which could be shed light via the single-cell level determination/bioanalysis. Hence, in this article we have reviewed the special characteristic differences among various kinds of typical single-cell bioanalysis strategies and electrochemical techniques, and then focused on the recent advance and special bio-applications of electrochemiluminescence and micro-nano electrochemical sensing mediated in single-cell bioimaging & bioanalysis. Especially, we have summarized the relevant research exploration of the possibility to establish the in-situ single-cell electrochemical methods to detect cell heterogeneity through determination of specific biomolecules and bioimaging of some important biological processes. Eventually, this review has explored some important advances of electrochemical single-cell detection techniques for the real-time cellular bioimaging and diagnostics of some disease lesions like tumors. It raises the possibility to provide the specific in-situ platform to exploit the versatile, sensitive, and high-resolution electrochemical single-cell analysis for the promising biomedical applications like rapid tracing of some disease lesions or in vivo bioimaging for precise cancer theranostics.
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Técnicas Biosensibles , Neoplasias , Humanos , Ecosistema , Técnicas Biosensibles/métodos , Tecnología , Neoplasias/diagnóstico , Análisis de la Célula Individual , Técnicas Electroquímicas/métodos , Mediciones Luminiscentes/métodosRESUMEN
BACKGROUND: Disability was a major public health problem in China. However, the prevalence of disabilities in community-dwelling adults and their relationships to chronic physical conditions were unclear. We aimed to estimate the prevalence of disabilities and associated factors among a large community-based cohort in China. METHODS: Participants who were local permanent residents aged 18 years or above and completed the disability assessments were selected from the Cohort study on Chronic Disease of Communities Natural Population in Beijing, Tianjin and Hebei (CHCN-BTH) from 2017 to 2019. Disability was assessed using five questions about impairments and activity limitations based on the International Classification of Functioning (ICF), Disability and Health. Univariate, multivariate and multilevel logistic regressions were conducted to estimate the associations between disabilities and associated factors. RESULTS: Totally, 12,871 community-dwelling adults completed the survey. Among of them, 12.9% (95% CI: 12.3%-13.5%) reported having any disability. The prevalence of any disability was significantly higher in participants who were older age, widowed, retired and smokers, had higher BMI, average monthly income < 5000 RMB, lower education level, lower physical exercise frequency and heavy physical labor. Multilevel logistic regressions showed that there were significant associations between disabilities with chronic physical conditions, especially in the vision impairment with lower back pain, and hearing impairment as well as difficulty walking without special equipment with injuries. CONCLUSIONS: Many Chinese adults suffered from disabilities. Sustained efforts should be made to develop specific population-based health promotion and prevention programs for disabilities in China. TRAIL REGISTRATION: ChiCTR1900024725 (25/07/2019).
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Personas con Discapacidad , Jubilación , Adulto , Humanos , Estudios de Cohortes , Prevalencia , China , Pueblos del Este de AsiaRESUMEN
Objective: This randomized double-blinded clinical study is to investigate the clinical efficacy of per-paravertebral disk ozone injection combined with steroids in the treatment of patients with chronic discogenic low back pain (CDLBP). Methods: Group A (N = 60) received a per-paravertebral injection of a steroid mixture of 10 mL with pure oxygen 20 mL, while group B (N = 60) received a per-paravertebral injection of a steroid mixture of 10 mL combined with ozone 20 mL (30 µg/mL). Injections were administered once a week for 3 weeks, with a follow-up of 6 months. Clinical outcomes were assessed at week 1, month 3, and month 6 with the help of Visual Analog Scale (VAS) scores and Macnab efficacy evaluation. Results: The VAS score of both group A (1.65 vs. 6.87, p = 0.000) and group B (1.25 vs. 6.85, p = 0.000) at week 1 was significantly reduced compared to baseline. The effect was sustained at the 3- and 6-month follow-up periods (p < 0.05). Group B had significantly lower VAS scores at month 3 (1.53 vs. 3.82, p = 0.000) and month 6 (2.80 vs. 5.05, p = 0.000) compared to group A, respectively. Based on Macnab criteria, 95 and 96.7% of patients in groups A and B had good rates "excellent plus good" at week 1, respectively. Good rates were significantly higher in group B at month 3 (91.7 vs. 78.3%, p = 0.041) and month 6 (85.0 vs. 68.3%, p = 0.031) compared to group A, respectively. No serious adverse events were noted in both groups. Conclusion: Per-paravertebral injection of steroid and ozone combination resulted in better relief of CDLBP compared to pure oxygen plus steroid. Clinical Trial Registration: ChiCTR2100044434 https://www.chictr.org.cn/showproj.html?proj=121571.
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BACKGROUND: We aimed to determine whether depressive, anxiety, stress symptoms were associated with the risk of elevated blood pressure by performing longitudinal cohort and Mendelian Randomization (MR) analyses. METHODS: We used data from the Cohort Study on Chronic Disease of Community Natural Population in the Beijing-Tianjin-Hebei region (CHCN-BTH) from 2017 to 2021. The Depression-Anxiety-Stress Scale was used to evaluate the depressive, anxiety, stress symptoms. The longitudinal associations between depressive, anxiety, stress symptoms and elevated blood pressure were estimated using Cox proportional regression models. Two-sample MR analysis was performed using the Inverse-variance weighted (IVW), weighted median, and MR-Egger to explore the causal relationships between depressive, anxiety, stress symptoms and elevated blood pressure. RESULTS: In total, 5624 participants were included. The risk of SBP ≥ 140 mmHg or DBP ≥ 90 mmHg was significantly higher in participants with baseline anxiety symptoms (HR = 1.48, 95 % CI: 1.03 to 2.12, P = 0.033; HR = 1.56, 95 % CI: 1.05 to 2.32, P = 0.028), especially in men and individuals with higher educational levels, independent of baseline depression and anxiety at the two-year follow-up. The two-sample MR analysis showed positive associations between depressive, anxiety, stress symptoms and elevated blood pressure. LIMITATION: Self-reported mental health symptoms, relatively shorter follow-up duration and the European-derived genome-wide association study data for MR analysis. CONCLUSIONS: Anxiety symptoms were positively associated with elevated blood pressures in the longitudinal analysis independent of depression, stress, and other confounders. The results were verified in MR analysis, providing evidence for causal effects of anxiety symptoms on the risk of elevated blood pressure.
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Hipertensión , Análisis de la Aleatorización Mendeliana , Masculino , Humanos , Presión Sanguínea , Estudios de Cohortes , Estudio de Asociación del Genoma Completo , Ansiedad/epidemiología , Ansiedad/genética , Hipertensión/epidemiología , Hipertensión/genéticaRESUMEN
OBJECTIVE: To investigate the association between folate levels and the risk of gestational diabetes mellitus (GDM) risk during the whole pregnancy. DESIGN: In this retrospective cohort study of pregnant women, serum folate levels were measured before 24 gestational weeks (GW). GDM was diagnosed between 24th and 28th GW based on the criteria of the International Association of Diabetes and Pregnancy Study Groups. General linear models were performed to examine the association of serum folate with plasma glucose (i.e. linear regressions) and risk of GDM (i.e. log-binomial regressions) after controlling for confounders. Restricted cubic spline regression was conducted to test the dosage-response relationship between serum folate and the risk of GDM. SETTING: A sigle, urban hospital in Shanghai, China. PARTICIPANTS: A total of 42 478 women who received antenatal care from April 2013 to March 2017 were included. RESULTS: Consistent positive associations were observed between serum folate and plasma glucose levels (fasting, 1-h, 2-h). The adjusted relative risks (RR) and 95 % CI of GDM across serum folate quartiles were 1·00 (reference), 1·15 (95 % CI (1·04, 1·26)), 1·40 (95 % CI (1·27, 1·54)) and 1·54 (95 % CI (1·40, 1·69)), respectively (P-for-trend < 0·001). The positive association between serum folate and GDM remained when stratified by vitamin B12 (adequate v. deficient groups) and the GW of serum folate measurement (≤13 GW v. >13 GWs). CONCLUSIONS: The findings of this study may provide important evidence for the public health and clinical guidelines of pregnancy folate supplementation in terms of GDM prevention.
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Diabetes Gestacional , Embarazo , Femenino , Humanos , Diabetes Gestacional/epidemiología , Glucemia , Estudios Retrospectivos , Pueblos del Este de Asia , China/epidemiología , Ácido FólicoRESUMEN
The time-resolved electron paramagnetic resonance (EPR) technique under operando photochemical conditions as an efficient strategy to investigate the fast formation of abundant long-lived PINO radicals (t1/2 = 204 s) and their activation of the C(sp3)-H process has been researched. This developed method offers a pathway for investigating the properties and tracking the transformations of radical species in the photoredox reaction process.
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Developing highly efficient catalytic protocols for C-sp(3)-H bond aerobic oxidation under mild conditions is a long-desired goal of chemists. Inspired by nature, a biomimetic approach for the aerobic oxidation of C-sp(3)-H by galactose oxidase model compound CuIIL and NHPI (N-hydroxyphthalimide) was developed. The CuIIL-NHPI system exhibited excellent performance in the oxidation of C-sp(3)-H bonds to ketones, especially for light alkanes. The biomimetic catalytic protocol had a broad substrate scope. Mechanistic studies revealed that the CuI-radical intermediate species generated from the intramolecular redox process of CuIILH2 was critical for O2 activation. Kinetic experiments showed that the activation of NHPI was the rate-determining step. Furthermore, activation of NHPI in the CuIIL-NHPI system was demonstrated by time-resolved EPR results. The persistent PINO (phthalimide-N-oxyl) radical mechanism for the aerobic oxidation of C-sp(3)-H bond was demonstrated.
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In order to understand species composition and diversity of fish communities in the ecotone between the Yellow Sea and Bohai Sea, we examined species composition and temporal and spatial variations of fish species diversity using the relative importance index (IRI), species diversity index and k dominance curve based on bottom trawl survey data of fish resources in the adjacent waters of the Changshan Islands in October 2016, January, May and August 2017. The results showed that 77 fish species were captured, mainly temperate water fishes, demersal fishes and migratory fishes. The dominant species exhibited obvious seasonal variation. The dominant species in spring and winter were Lophius litulon, and those in summer were pelagic species such as Scomber japonicus and Engraulis japonicus. A total of 46 migratory fish species were found throughout the year. The seasonal species migration indices were all higher than 100, while the species migration index was the largest in autumn. The species diversity index showed high spatial and temporal dynamics, with the highest species richness in spring and the highest Shannon diversity and evenness in autumn. There was a significant negative correlation between species richness and sea surface temperature in summer, significant positive correlations between species richness and depth and bottom temperature in winter, and a significant positive correlation between Shannon diversity index and sea bottom temperature. In short, fish community showed high species diversity, rich migratory species and obvious temporal and spatial heterogeneity in the adjacent waters of the Changshan Islands, which is an ecotone between the Yellow Sea and the Bohai Sea.