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1.
Chem Biol Interact ; 360: 109934, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35429547

RESUMO

Acrylonitrile is an organic chemical synthetic monomer that is widely used in food packaging and manufacturing. Animal studies have reported that acrylonitrile is carcinogenic and toxic, but the effects on the female reproductive function in mammals are unknown. In the present study, we report that acrylonitrile treatment affects ovarian homeostasis in mice, resulting in impaired follicular development. Follicles in acrylonitrile-exposed mice exhibited high levels of inflammation and apoptosis, and acrylonitrile treatment interfered with oocyte development. Transcriptomics analysis showed that acrylonitrile altered the expression of oocyte genes related to apoptosis, oxidative stress, endoplasmic reticulum stress, and autophagy. Further molecular tests revealed that acrylonitrile induced early apoptosis, DNA damage, elevated levels of reactive oxygen species, endoplasmic reticulum abnormalities, and lysosomal aggregation. We also observed disruption of mitochondrial structure and distribution and depolarization of membrane potential. Finally, acrylonitrile treatment in female mice decreased the number and weight of offspring. Altogether, these findings suggest that acrylonitrile impairs the stability of the ovarian internal environment, which in turn affects oocyte development and reduces the number of offspring.


Assuntos
Acrilonitrila , Acrilonitrila/metabolismo , Acrilonitrila/toxicidade , Animais , Apoptose , Feminino , Inflamação/metabolismo , Mamíferos , Camundongos , Mitocôndrias/metabolismo , Oócitos
2.
Environ Sci Technol ; 56(8): 4795-4805, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35235293

RESUMO

Isoprene is the most abundant precursor of global secondary organic aerosol (SOA). The epoxide pathway plays a critical role in isoprene SOA (iSOA) formation, in which isoprene epoxydiols (IEPOX) and/or hydroxymethyl-methyl-α-lactone (HMML) can react with nucleophilic sulfate and water producing isoprene-derived organosulfates (iOSs) and oxygen-containing tracers (iOTs), respectively. This process is complicated and highly influenced by anthropogenic emissions, especially in the polluted urban atmospheres. In this study, we took a 1-year measurement of the paired iOSs and iOTs formed through the IEPOX and HMML pathways at the three urban sites from northern to southern China. The annual average concentrations of iSOA products at the three sites ranged from 14.6 to 36.5 ng m-3. We found that the nucleophilic-addition reaction of isoprene epoxides with water dominated over that with sulfate in the polluted urban air. A simple set of reaction rate constant could not fully describe iOS and iOT formation everywhere. We also found that the IEPOX pathway was dominant over the HMML pathway over urban regions. Using the kinetic data of IEPOX to estimate the reaction parameters of HMML will cause significant underestimation in the importance of HMML pathway. All these findings provide insights into iSOA formation over polluted areas.


Assuntos
Poluentes Atmosféricos , Compostos de Epóxi , Aerossóis/análise , Butadienos , Hemiterpenos , Pentanos , Sulfatos , Água
3.
Glob Heart ; 17(1): 10, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35342697

RESUMO

Objective: This study aimed to evaluate the association between sleep duration and hypertension among adults in southwest China. Methods: Baseline variables were collected from a representative sample of 20,053 adults aged 23-98 years in southwest China who received physical examinations from January 2019 to December 2020. All participants were categorized into either a hypertension group or a non-hypertension group. Sleep duration was classified as short (<6 h/day), normal (6-8 h/day),or long (>8 h/day). Baseline variables were compared between individuals with and without hypertension by rank-sum tests for two independent samples or χ2 tests for nonparametric data. Multivariate logistic regression analysis was performed to evaluate the association between sleep duration and hypertension. Results: The overall incidence of hypertension was 51.2%. Unadjusted analysis showed that the risk of hypertension was higher in individuals with short (<6h/day) or long (>8h/day) sleep durations compared with those with a normal (6-8 h/day) sleep duration. The risk of hypertension was significantly increased by 30.1% in participants with a long (>8h/day) sleep duration compared with those with a normal (6-8h/day) sleep duration (OR = 1.301, P < 0.010, 95%CI = 1.149-1.475). The risk of hypertension was also increased by 1.1% in participants with a short (<6h/day) sleep duration compared with participants with a normal (6-8h/day) sleep duration, but the difference was not significant (OR = 1.011, P = 0.849, 95%CI = 0.905-1.129). After fully adjusting for confounding factors (model 4), the risk of hypertension was increased significantly (by 25%) in individuals with a short (<6h/day) sleep duration (OR = 1.25, P = 0.02, 95%CI = 1.036-1.508) but not in those with a long (>8h/day) sleep duration (17.5% increase) compared with participants with a normal (6-8h/day) sleep duration (OR = 1.175, P = 0.144, 95%CI = 0.946-1.460). Conclusion: The results of this study indicate that a short (<6h/day) sleep duration is related to an increased risk of hypertension, suggesting that sleep helps to protect against hypertension.


Assuntos
Hipertensão , Adulto , China/epidemiologia , Humanos , Fatores de Risco , Sono
4.
Complement Ther Med ; 65: 102809, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35093513

RESUMO

BACKGROUND: Liuzijue is a traditional Qigong exercise that is commonly performed in China. However, the treatment effects of Liuzijue Qigong are controversial. The aim of this systematic review was to evaluate the efficacy of Liuzijue Qigong in patients with chronic obstructive pulmonary disease (COPD). METHODS: Randomised controlled trials were identified by searching several English and Chinese databases from inception to August 8, 2020. Study selection and data extraction were independently performed by two investigators. Data synthesis and analysis were carried out with Review Manager software 5.2. Quality assessment for each study was based on the modified Jadad scale. RESULTS: Forty studies with 3137 participants were included. Significant improvements were observed in the following outcomes (mean difference, 95% confidence interval): forced expiratory volume in 1 s (0.17, 0.09-0.25) and its percent predicted normal value (6.04, 3.43-8.65), forced expiratory volume in 1 s to forced volume capacity ratio (6.95, 3.06-10.83), 6-min walking distance (33.06, 23.73-42.38), 30-s sit-to-stand test (2.65, 0.98-4.32), COPD assessment test score (- 2.04, - 2.77 to - 1.30), modified Medical Research Council dyspnea scale (- 0.34, - 0.48 to - 0.20), Medical Research Council dyspnea scale (- 0.37, - 0.57 to - 0.18), Traditional Chinese Medicine syndrome score (- 1.85, - 2.86 to - 0.85), Hamilton Anxiety Scale (- 2.31, - 3.04 to - 1.59), Hamilton Depression Scale (- 2.08, - 2.45 to - 1.71) and St. George's Respiratory Questionnaire (- 6.94, - 9.20 to - 4.67). CONCLUSIONS: Liuzijue Qigong may be an effective adjuvant therapy for the improvement of lung function, exercise capacity, health status, mental status and quality of life in patients with COPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Qigong , Volume Expiratório Forçado , Humanos , Doença Pulmonar Obstrutiva Crônica/terapia , Qualidade de Vida , Testes de Função Respiratória
5.
Front Med (Lausanne) ; 9: 850966, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35492370

RESUMO

Introduction: Increasing evidence supports the idea that the disruption of epithelial tight junction proteins (TJPs) caused by accumulation of uremia toxins, such as homocysteine (Hcy), is one of the most important mechanisms underlying the damage of intestinal barrier function (IBF) in chronic kidney disease (CKD). Since the decrease of hypoxia inducible factor-1α (HIF-1α) is reported to be involved in Hcy-induced cell injury, and the upregulation of microRNA-223 (miR-223) plays a vital protective role in the impairment of IBF in the experimental colitis, we investigated the effect of HIF-1α stabilizer roxadustat on the disruption of TJPs induced by Hcy and CKD and the underlying mechanism. Methods: Chronic kidney disease was induced in rats via 5/6 nephrectomy. In a series of experiments, the rats were treated orally with roxadustat of different doses. The expression of tight junction proteins, HIF-1α, and miR-223 was analyzed in different groups by western blotting analysis, RT-qPCR techniques and immunofluorescence. A series of experiments with cultured Caco2 cells was performed. Results: The results showed that the expression of TJPs (occludin, claudin-1, and ZO-1) decreased significantly, accompanied by the reduction of HIF-1α and miR-223 in Hcy-treated Caco2 cells and colonic mucosa of uremic rats. The reduction of HIF-1α and miR-223 was reversed by roxadustat and the decrease of TJPs expression was attenuated in both Caco2 cells induced by Hcy and colon tissue of CKD rats. Furthermore, transfection with miR-223 mimics increased the expression of TJPs, while transfection with miR-223 inhibitor decreased their expression in Caco2 cells. MiR-223 inhibitor applied before roxadustat treatment partly diminished the effect of roxadustat on TJPs expression in Caco2 cells. Conclusion: These results indicated that roxadustat attenuated the disruption of epithelial TJPs induced by Hcy in Caco2 cells and the damage of colonic epithelium in CKD rats through the upregulation of miR-223 induced by HIF-1α. A novel insight into the IBF dysfunction in CKD was provided, and it suggests a potential therapeutic use of roxadustat for the IBF dysfunction besides anemia in CKD.

6.
Chemosphere ; 286(Pt 1): 131625, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34303901

RESUMO

Captan is a non-systematic fungicide widely used in agricultural production, and its residues have been found in the environment and daily diet. Previous studies confirmed that captan exerts several toxic effects on tissues, but its effect on the mammalian female reproductive system is unclear. In current study, we reported that captan affected mouse ovarian homeostasis and disrupted female hormone receptor expression, leading to impaired follicular development. Ovarian follicles from the captan exposure group showed an increased level of inflammation, endoplasmic reticulum stress and apoptosis. In addition, captan exposure disrupted oocyte development. Transcriptomic analysis indicated that captan changed multiple genes expression in oocytes, including autophagy and apoptosis. Further molecular testing showed that captan induced oxidative stress and mitochondrial dysfunction, as indicated by the increased level of reactive oxygen species, disrupted mitochondrial structure and distribution, and depolarized membrane potential. Furthermore, captan triggered DNA damage, autophagy and early apoptosis, as shown by the enhanced levels of γ-H2AX, LC3, and Annexin-V and increased expression of related genes. Taken together, these results indicated that captan exposure impairs ovarian homeostasis and subsequently affects oocyte development.


Assuntos
Captana , Oócitos , Animais , Apoptose , Captana/metabolismo , Feminino , Homeostase , Camundongos , Mitocôndrias/metabolismo , Oócitos/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
8.
Nature ; 600(7887): 81-85, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34853456

RESUMO

Understanding the structure and dynamic process of water at the solid-liquid interface is an extremely important topic in surface science, energy science and catalysis1-3. As model catalysts, atomically flat single-crystal electrodes exhibit well-defined surface and electric field properties, and therefore may be used to elucidate the relationship between structure and electrocatalytic activity at the atomic level4,5. Hence, studying interfacial water behaviour on single-crystal surfaces provides a framework for understanding electrocatalysis6,7. However, interfacial water is notoriously difficult to probe owing to interference from bulk water and the complexity of interfacial environments8. Here, we use electrochemical, in situ Raman spectroscopic and computational techniques to investigate the interfacial water on atomically flat Pd single-crystal surfaces. Direct spectral evidence reveals that interfacial water consists of hydrogen-bonded and hydrated Na+ ion water. At hydrogen evolution reaction (HER) potentials, dynamic changes in the structure of interfacial water were observed from a random distribution to an ordered structure due to bias potential and Na+ ion cooperation. Structurally ordered interfacial water facilitated high-efficiency electron transfer across the interface, resulting in higher HER rates. The electrolytes and electrode surface effects on interfacial water were also probed and found to affect water structure. Therefore, through local cation tuning strategies, we anticipate that these results may be generalized to enable ordered interfacial water to improve electrocatalytic reaction rates.

9.
Front Pharmacol ; 12: 733805, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721023

RESUMO

Objective: Pirarubicin (THP), one of the anthracycline anticancer drugs, is widely used in the treatment of various cancers, but its cardiotoxicity cannot be ignored. Schisandrin B (SchB) has the ability to upregulate cellular antioxidant defense mechanism and promote mitochondrial function and antioxidant status. However, it has not been reported whether it can resist THP-induced cardiotoxicity. The aim of this study was to investigate the effect of SchB on THP cardiotoxicity and its mechanism. Methods: The rat model of cardiotoxicity induced by THP was established, and SchB treatment was performed at the same time. The changes of ECG, cardiac coefficient, and echocardiogram were observed. The changes of myocardial tissue morphology were observed by H&E staining. Apoptosis was detected by TUNEL. The levels of LDH, BNP, CK-MB, cTnT, SOD, and MDA in serum were measured to observe the heart damage and oxidative stress state of rats. The expression of cleaved-caspase 9, pro/cleaved-caspase 3, Bcl-2/Bax, and cytosol and mitochondrial Cyt C and Bax was evaluated by western blot. H9c2 cardiomyocytes were cocultured with THP, SchB, and mPTP inhibitor CsA to detect the production of ROS and verify the above signaling pathways. The opening of mPTP and mitochondrial swelling were detected by mPTP kit and purified mitochondrial swelling kit. Results: After 8 weeks, a series of cardiotoxicity manifestations were observed in THP rats. These adverse effects can be effectively alleviated by SchB treatment. Further studies showed that SchB had strong antioxidant and antiapoptotic abilities in THP cardiotoxicity. Conclusion: SchB has an obvious protective effect on THP-induced cardiotoxicity. The mechanism may be closely related to the protection of mitochondrial function, inhibition of mPTP opening, and alleviation of oxidative stress and apoptosis of cardiomyocytes.

10.
Molecules ; 26(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34770975

RESUMO

Acyclovir (ACV) is an effective and selective antiviral drug, and the study of its toxicology and the use of appropriate detection techniques to control its toxicity at safe levels are extremely important for medicine efforts and human health. This review discusses the mechanism driving ACV's ability to inhibit viral coding, starting from its development and pharmacology. A comprehensive summary of the existing preparation methods and synthetic materials, such as 5-aminoimidazole-4-carboxamide, guanine and its derivatives, and other purine derivatives, is presented to elucidate the preparation of ACV in detail. In addition, it presents valuable analytical procedures for the toxicological studies of ACV, which are essential for human use and dosing. Analytical methods, including spectrophotometry, high performance liquid chromatography (HPLC), liquid chromatography/tandem mass spectrometry (LC-MS/MS), electrochemical sensors, molecularly imprinted polymers (MIPs), and flow injection-chemiluminescence (FI-CL) are also highlighted. A brief description of the characteristics of each of these methods is also presented. Finally, insight is provided for the development of ACV to drive further innovation of ACV in pharmaceutical applications. This review provides a comprehensive summary of the past life and future challenges of ACV.


Assuntos
Aciclovir/efeitos adversos , Aciclovir/análise , Antivirais/efeitos adversos , Antivirais/análise , Aciclovir/síntese química , Antivirais/síntese química , Humanos , Estrutura Molecular
11.
Front Nutr ; 8: 700936, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34746200

RESUMO

Objective: This review aimed to systematically summarize and meta-analyze the association between eating speed and metabolic syndrome (MetS). Methods: Following the Preferred Reporting Items for Systematic Reviews, and Meta Analyses (PRISMA) guidelines, four electronic databases (PubMed, Web of Science, MEDLINE, and EMBASE) were searched until March 2021 to identify eligible articles based on a series of inclusion and exclusion criteria. Heterogeneity was examined using I 2 statistics. Using random-effects models, the pooled odds ratios (ORs), and 95% CIs were calculated to evaluate the association between eating speed with MetS and its components, including central obesity, blood pressure (BP), high-density lipoprotein cholesterol (HDL), triglyceride (TG), and fasting plasma glucose (FPG). Results: Of the 8,500 original hits generated by the systematic search, 29 eligible studies with moderate-to-high quality were included, involving 465,155 subjects. The meta-analysis revealed that eating faster was significantly associated with higher risks of MetS (OR = 1.54, 95% CI: 1.27-1.86), central obesity (OR = 1.54, 95% CI: 1.37-1.73), elevated BP (OR = 1.26, 95% CI: 1.13-1.40), low HDL (OR = 1.23, 95% CI: 1.15-1.31), elevated TG (OR = 1.29, 95% CI: 1.18-1.42), and elevated FPG (OR = 1.16, 95% CI: 1.06-1.27) compared to eating slowly. Conclusions: The results of the review indicated that eating speed was significantly associated with MetS and its components. Interventions related to decreasing eating speed may be beneficial for the management of MetS. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021242213, identifier: CRD42021242213.

12.
Opt Express ; 29(21): 34850-34862, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809265

RESUMO

Plasmonic metasurfaces can be used to replace traditional polarization devices for various integrated optical devices because of their novel polarization control ability on a subwavelength scale. In particular, the asymmetric transmission of circularly polarized light by anisotropic metasurface has attracted much attention recently. Here, a simple and effective circular polarization converter composed of three layers of rotated gold split-rings and a Si3N4 substrate is proposed, which is appropriate for both transmission and reflection modes. For transmission mode, it can convert left- and right- handed circularly polarized light into orthogonally polarized light in two adjacent bands with conversion efficiencies of 65% and 75%, respectively. For the reflection mode, the mutual conversion efficiencies can be up to 58% and 64%, respectively. Meanwhile, the structure has moderate asymmetric transmission and reflection efficiencies. The operating band of the metasurface can be adjusted continuously and linearly by changing the refractive index of the substrate. The dual-band asymmetric effects may contribute to information encoding and decoding for communication applications. As an ultra-thin planar optical element, the proposed metasurface can be used in integrated photonics, optical sensing, and other fields.

13.
Biology (Basel) ; 10(10)2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34681058

RESUMO

We conducted a meta-analysis to systematically assess the prevalence of hyperhomocysteinemia (HHcy) in China, its change over time, and its determinants. Literature searches were conducted using English databases (PubMed, Embase, and Web of Science) and Chinese databases (CNKI, CBM, VIP, and Wanfang). The time ranges were from Jan 2014 to Mar 2021 in China. We adopted the random effects model to estimate the pooled positive rates of HHcy and corresponding 95% confidence intervals (95% CI). To find the sources of heterogeneity, we performed subgroup analysis and meta-regression. A total of 29 related articles were identified involving 338,660 participants with 128,147 HHcy cases. The estimated prevalence of HHcy in China was 37.2% (95% CI: 32.6-41.8%, I2 = 99.8%, p for heterogeneity < 0.001). The trend of HHcy prevalence was gradually upward over time, with increases during 2015-2016 (comparison to 2013-2014, p < 0.001), but steady between 2015-2016 and 2017-2018. Subgroup analysis showed that the prevalence was higher in the elderly over 55 years old, males, and residents in the north, inland, and rural China (for each comparison, p < 0.001). Meta-regression analysis revealed that age and area of study contributed to 42.3% of the heterogeneity between studies. The current meta-analysis provides strong evidence that the prevalence of HHcy is increasing in China, and varies substantially across different ages, genders, and geographic distribution. Accordingly, high-risk population groups should be focused on, and public health policies and strategies should be carried out to prevent and control HHcy in China.

14.
Ecotoxicol Environ Saf ; 224: 112634, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34392153

RESUMO

Nickel is a heavy metal element extensively distributed in the environment and widely used in modern life. Divalent nickel is one of the most widespread forms of nickel and has been reported as toxic to various tissues. However, whether exposure to divalent nickel negatively affects ovarian homeostasis and oocyte quality remains unclear. In this study, we found that 3 weeks of nickel sulfate exposure affected body growth and decreased the weight and coefficient of the ovary, and increased atretic follicles exhibiting enhanced apoptosis in granulosa cells. Further studies have found that nickel sulfate triggered ovarian fibrosis and inflammation via transforming growth factor-ß1 and nuclear factor-κB pathways, and reduced oocyte development ability. In addition, nickel sulfate increased the level of reactive oxygen species, which induced DNA damage and early apoptosis. Moreover, it was found that nickel sulfate caused damage to the mitochondria showing aberrant morphology, distribution and membrane potential while decreased levels of histone methylation. To summarize, our results indicated that nickel sulfate exposure triggered ovarian fibrosis and inflammation and caused structural and functional disorders of mitochondria in oocytes, which consequently disturbed ovarian homeostasis and follicle development and decreased oocyte quality.

15.
Analyst ; 146(18): 5682-5690, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34397059

RESUMO

A novel, convenient ambient electric arc ionization (AEAI) device was developed as a mass spectrometry ion source for versatile sample analysis. AEAI could be considered as a soft ionization technique in which the protonated ion ([M + H]+) is the main ion species with little or no in-source fragmentation for most analytes. Coupled with a high-resolution Orbitrap mass spectrometer, AEAI could be applied to the analysis of a variety of organic compounds having a wide range of polarities, ranging from non-polar species such as polybenzenoid aromatic hydrocarbons (PAHs) to highly polar species such as amino acids. With its versatile capabilities in the mass spectrometric analysis of small molecules, AEAI has the potential to be an alternative to traditional ionization methods such as electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI), and electron impact (EI) ionization. The limitations of AEAI are also discussed.


Assuntos
Pressão Atmosférica , Compostos Orgânicos , Aminoácidos , Espectrometria de Massas , Espectrometria de Massas por Ionização por Electrospray
16.
Front Cell Infect Microbiol ; 11: 579766, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222033

RESUMO

Background: Preterm birth is one of the leading causes of perinatal morbidity and mortality. Gut microbiome dysbiosis is closely related to adverse pregnancy outcomes. However, the role of the gut microbiome in the pathogenesis of preterm birth remains poorly studied. Method: We collected fecal samples from 41 women (cases presenting with threatened preterm labor =19, 11 of which delivered preterm; gestational age-matched no-labor controls, all of which delivered at term = 22) were recruited for the study. We performed 16S rRNA amplicon sequencing to compare the composition of the gut microbiome in threatened preterm labor cases and controls and among women who delivered preterm and at term. By annotating taxonomic biomarkers with the Human Oral Microbiome Database, we observed an increased abundance of potential oral-to-gut bacteria in preterm patients. Results: Patients with preterm birth showed a distinct gut microbiome dysbiosis compared with those who delivered at term. Opportunistic pathogens, particularly Porphyromonas, Streptococcus, Fusobacterium, and Veillonella, were enriched, whereas Coprococcus and Gemmiger were markedly depleted in the preterm group. Most of the enriched bacteria were annotated oral bacteria using the Human Oral Microbiome Database. These potential oral-to-gut bacteria were correlated with clinical parameters that reflected maternal and fetal status. Conclusions: This study suggests that patients who deliver preterm demonstrate altered gut microbiome that may contain higher common oral bacteria.


Assuntos
Microbioma Gastrointestinal , Microbiota , Nascimento Prematuro , Disbiose , Feminino , Humanos , Recém-Nascido , Gravidez , RNA Ribossômico 16S/genética
17.
J Proteome Res ; 20(8): 3952-3962, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34229439

RESUMO

Screening of characteristic biomarkers from chiral amino-containing metabolites in biological samples is difficult and important for the noninvasive diagnosis of gastric cancer (GC). Here, an enantiomeric pair of chlorine-labeled probes d-BPCl and l-BPCl was synthesized to selectively label d- and l-amino-containing metabolites in biological samples, respectively. Incorrect structural annotations were excluded according to the characteristic 3:1 abundance ratio of natural chlorine isotopes (35Cl and 37Cl) derived from the probes. A sensitive C18 HPLC-QQQ-MS/MS method in combination with the probes was then developed and applied in metabolomic analysis of amino-containing metabolites in urine samples. A total of 161 amino-containing metabolites were rapidly separated and determined, and 28 chiral amino acids and achiral glycine were quantified with good precision and accuracy. A total of 18 differential variables were discriminated by analyzing chiral amino-containing metabolites in urine samples of the GC patient and healthy person using the probe-based HPLC-MS/MS-MRM method combined with the orthogonal partial least squares discriminant analysis and Mann-Whitney U test with false discovery rate correction for multiple hypotheses. A diagnostic regression model including d-isoleucine, d-serine, and ß-(pyrazol-1-yl)-l-alanine and age was then constructed with an average prediction correctness of 88.9% in the validation set. This work established a close connection between gastric cancer and chiral amino-containing metabolites. The mass spectrometry data analyzed in the study are publicly available via Mendeley Data (DOI: 10.17632/4bd93j9yrr.1).


Assuntos
Cloro , Neoplasias Gástricas , Biomarcadores , Cromatografia Líquida de Alta Pressão , Humanos , Metabolômica , Neoplasias Gástricas/diagnóstico , Espectrometria de Massas em Tandem
18.
Basic Res Cardiol ; 116(1): 47, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34319513

RESUMO

Altered autophagy is implicated in several human cardiovascular diseases. Remote ischemic conditioning (RIC) is cardioprotective in multiple cardiovascular injury models and modifies autophagy signaling, but its effect in cardiomyopathy induced by gene manipulation has not been reported. To investigate the cardiac effects of chronically reduced autophagy as a result of Atg5 knockdown and assess whether RIC can rescue the phenotype. Atg5 knockdown was induced with tamoxifen for 14 days in cardiac-specific conditional Atg5 flox mice. Autophagy proteins and cardiac function were evaluated by Western blot and echocardiography, respectively. RIC was induced by cyclical hindlimb ischemia and reperfusion using a tourniquet. RIC or sham procedure was performed daily during tamoxifen induction and, in separate experiments, chronically 3 times per week for 8 weeks. Cardiac responses were assessed by end of the study. Cardiac-specific knockdown of Atg5 reduced protein levels by 70% and was associated with a significant increase in mTOR, a reduction of LC3-II and increased upstream autophagy proteins including LC3-I, P62, and Beclin. The changes in biochemical markers were associated with development of an age-related cardiomyopathy during the 17-month follow-up indicated by increased heart weight body weight ratio, progressive decline in cardiac function, and premature death. RIC increased cardiac ATG5 and rescued some of the Atg5 knockdown-induced cardiomyopathy phenotype and associated morphological remodeling. We conclude that cardiac-specific Atg5 knockdown leads to the development of age-related cardiomyopathy. RIC reverses the molecular and structural phenotype when administered both acutely and chronically.


Assuntos
Cardiomiopatias , Animais , Autofagia , Proteína 5 Relacionada à Autofagia/genética , Cardiomiopatias/genética , Coração , Isquemia , Camundongos , Transdução de Sinais
19.
Anal Chim Acta ; 1170: 338480, 2021 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-34090586

RESUMO

Since the discovery of liquid-phase-exfoliated black phosphorus (BP) as a field-effect transistor in 2014, BP, with its 2D layered structure, has attracted significant attention, owing to its anisotropic electroconductivity, tunable direct bandgap, extraordinary surface activity, moderate switching ratio, high hole mobility, good biocompatibility, and biodegradability. Several pioneering research efforts have explored the application of BP in different types of electrochemical sensors. This review summarizes the latest synthesis methods, protection strategies, and electrochemical sensing applications of BP and its derivatives. The typical synthesis methods for BP-based crystals, nanosheets, and quantum dots are discussed in detail; the degradation of BP under ambient conditions is introduced; and state-of-the-art protection methodologies for enhancing BP stability are explored. Various electrochemical sensing applications, including chemically modified electrodes, electrochemiluminescence sensors, enzyme electrodes, electrochemical aptasensors, electrochemical immunosensors, and ion-selective electrodes are discussed in detail, along with the mechanisms of BP functionalization, sensing strategies, and sensing properties. Finally, the major challenges in this field are outlined and future research avenues for BP-based electrochemical sensors are highlighted.

20.
Iran J Basic Med Sci ; 24(4): 493-498, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34094031

RESUMO

OBJECTIVES: Kaempferide (Ka), a major natural active component of Tagetes erecta L, has numerous pharmacological effects such as anti-obesity, anticancer, and anti-hypertension. However, there is no clear evidence that Ka is directly related to inflammation and oxidative stress in obese mice. We aimed to explore the effects of Ka on inflammation and oxidative stress and its mechanism. MATERIALS AND METHODS: The obese mice were induced by a high-fat diet (HFD). The anti-obesity effect was tested by liver and body weight, liver and adiposity index, and white adipose tissue. Blood sample analysis was used to detect the hypolipidemic and hypoglycemic effects. The anti-oxidation effect was assessed using GSH, SOD, MDA, CAT, T-AOC, and other indicators. The anti-inflammatory effect was assessed using TNF-α, MCP-1, and Adiponectin. Western blot and Real-Time PCR were used to evaluate the related signaling pathways. RESULTS: Obesity, glycolipid metabolism disorder, inflammation, and oxidative stress developed in HFD mice. These changes can be effectively alleviated by Ka treatment for 16 weeks. Further studies have suggested that these beneficial effects of Ka may be associated with inhibition of the TLR4/IκBα/NF-κB signaling pathways. CONCLUSION: Ka possesses important anti-obesity, hypoglycemic, and hypolipidemic effects. The mechanism may be causally associated with the TLR4/IκBα/NF-κB signaling pathway, which improves inflammation and oxidative stress.

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