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1.
Huan Jing Ke Xue ; 45(2): 700-708, 2024 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-38471910

RESUMEN

Organic acids in atmospheric particulate matter are widely involved in various physical and chemical reactions in the atmosphere and contribute greatly to the formation of secondary organic aerosols and haze pollutions. Therefore, the concentration distribution characteristics, sources, and secondary formation of organic acids in particulate matter are of great significance for further investigation of organic aerosols and their secondary transformation. Fine particulate matter (PM2.5) samples were collected in Zhengzhou, and three types of organic acids, including dicarboxylic acids, fatty acids, and resin acids, were analyzed to explore their species distribution, seasonal variations, source contribution, and secondary generation. Malonic acid (di-C3) and succinate acid (di-C4) were the most abundant in the identified dicarboxylic acids, which showed obvious seasonal variations in the order of summer > autumn > winter > spring. Fatty acids had the highest concentration in winter and the lowest concentration in spring, showing obvious bimodal advantages, with the most abundant compounds being palmitic acid and stearic acid (C18). Principal component analysis and multiple linear regression (MLR) were used to analyze the source of organic acids in PM2.5 in Zhengzhou; the results showed that 35% of the organic acids came from combustion and traffic sources, 24% from cooking sources, 23% from secondary formation, and 17% from natural sources. The ratios of the selected marker species (i.e., di-C3 / di-C4, F/M, and C18:1 / C18) were used as tracers for the secondary formation of the organic aerosol and its aging process. The results showed that the photochemical reaction was intense in summer, and the proportion of organic aerosol aging or secondary production was high, whereas the photochemical reaction was weak in winter, and the aging degree of organic aerosol was low. Correlation analysis and MLR were used in combination to quantify the relative contribution of gas-phase oxidation and liquid-phase oxidation to dicarboxylic acid formation, and the results showed that gas-phase oxidation played a dominant role in the sampling period (accounting for 58%), especially in summer (61%).

2.
Chem Commun (Camb) ; 60(31): 4210-4213, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38525587

RESUMEN

The unprecedented copper-catalyzed asymmetric alkynylallylic monofluoroalkylation reaction is described via the use of 1,3-enynes and fluorinated malonates. A series of 1,4-enynes bearing a monofluoroalkyl unit are achieved in high yields, excellent regio- and enantioselectivity and high E/Z selectivity. The asymmetric propargylic monofluoroalkylation is also developed. The reliability and synthetic value of the work are highlighted by a gram-scale test and a couple of downstream transformations. Preliminary mechanistic studies unveil a negative nonlinear effect for the catalytic process.

3.
Food Funct ; 15(6): 2920-2938, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38385354

RESUMEN

Parkinson's disease (PD) is a common, chronic, and progressive degenerative disease of the central nervous system for which there is no effective treatment. Gastrodia elata is a well-known food and medicine homologous resource with neuroprotective potential. Gastrodia elata polysaccharide (GEP), which is a highly active and safe component in Gastrodia elata, is an important ingredient in the development of functional products. In this study, GEP was administered to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mice over 3 weeks to investigate its neuroprotective effects. The results showed that GEP significantly alleviated the motor dysfunction of PD mice, inhibited the accumulation of α-synuclein, and reduced the loss of dopaminergic neurons in the brain. Moreover, GEP increased the Bcl-2/Bax ratio and decreased the cleaved-caspase-3 level, suggesting that GEP may ameliorate PD by preventing MPTP-induced mitochondrial apoptosis. GEP also significantly inhibited the increase of GFAP and decreased the levels of TNF-α, IL-1ß, and IL-6 in the brain of PD mice, which may be the result of the inhibition of neuroinflammation by the inactivation of the TLR4/NF-κB pathway. Furthermore, the neuroprotective effects of GEP involve the gut-brain axis, as it has been shown that GEP regulated the dysbiosis of PD-related gut microbiota such as Akkermansia, Lactobacillus, Bacteroides, Prevotella, and Faecalibacterium, increased the content of microbial metabolites SCFAs in the colon and increased the level of occludin that repairs the intestinal barrier of PD mice. In conclusion, this study is expected to provide a theoretical basis for the development and application of functional products with GEP from the perspective of neuroprotective effects.


Asunto(s)
Gastrodia , Microbioma Gastrointestinal , Fármacos Neuroprotectores , Enfermedad de Parkinson , Ratones , Animales , Enfermedad de Parkinson/metabolismo , Fármacos Neuroprotectores/farmacología , Transducción de Señal , Polisacáridos/farmacología
4.
Med Image Anal ; 94: 103109, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38387243

RESUMEN

In computational pathology, multiple instance learning (MIL) is widely used to circumvent the computational impasse in giga-pixel whole slide image (WSI) analysis. It usually consists of two stages: patch-level feature extraction and slide-level aggregation. Recently, pretrained models or self-supervised learning have been used to extract patch features, but they suffer from low effectiveness or inefficiency due to overlooking the task-specific supervision provided by slide labels. Here we propose a weakly-supervised Label-Efficient WSI Screening method, dubbed LESS, for cytological WSI analysis with only slide-level labels, which can be effectively applied to small datasets. First, we suggest using variational positive-unlabeled (VPU) learning to uncover hidden labels of both benign and malignant patches. We provide appropriate supervision by using slide-level labels to improve the learning of patch-level features. Next, we take into account the sparse and random arrangement of cells in cytological WSIs. To address this, we propose a strategy to crop patches at multiple scales and utilize a cross-attention vision transformer (CrossViT) to combine information from different scales for WSI classification. The combination of our two steps achieves task-alignment, improving effectiveness and efficiency. We validate the proposed label-efficient method on a urine cytology WSI dataset encompassing 130 samples (13,000 patches) and a breast cytology dataset FNAC 2019 with 212 samples (21,200 patches). The experiment shows that the proposed LESS reaches 84.79%, 85.43%, 91.79% and 78.30% on the urine cytology WSI dataset, and 96.88%, 96.86%, 98.95%, 97.06% on the breast cytology high-resolution-image dataset in terms of accuracy, AUC, sensitivity and specificity. It outperforms state-of-the-art MIL methods on pathology WSIs and realizes automatic cytological WSI cancer screening.


Asunto(s)
Mama , Procesamiento de Imagen Asistido por Computador , Humanos
5.
Adv Sci (Weinh) ; 11(17): e2308548, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38400593

RESUMEN

High-performance and air-stable single-molecule magnets (SMMs) can offer great convenience for the fabrication of information storage devices. However, the controversial requisition of high stability and magnetic axiality is hard to balance for lanthanide-based SMMs. Here, a family of dysprosium(III) crown ether complexes possessing hexagonal-bipyramidal (pseudo-D6h symmetry) local coordination geometry with tunable air stability and effective energy barrier for magnetization reversal (Ueff) are shown. The three complexes share the common formula of [Dy(18-C-6)L2][I3] (18-C-6 = 1,4,7,10,13,16-hexaoxacyclooctadecane; L = I, 1; L = OtBu 2 and L = 1-AdO 3). 1 is highly unstable in the air. 2 can survive in the air for a few minutes, while 3 remains unchanged in the air for more than 1 week. This is roughly in accordance with the percentage of buried volumes of the axial ligands. More strikingly, 2 and 3 show progressive enhancement of Ueff and 3 exhibits a record high Ueff of 2427(19) K, which significantly contributes to the 100 s blocking temperature up to 11 K for Yttrium-diluted sample, setting a new benchmark for solid-state air-stable SMMs.

6.
Proc Natl Acad Sci U S A ; 120(37): e2309714120, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37669377

RESUMEN

Proofreading (editing) of mischarged tRNAs by cytoplasmic aminoacyl-tRNA synthetases (aaRSs), whose impairment causes neurodegeneration and cardiac diseases, is of high significance for protein homeostasis. However, whether mitochondrial translation needs fidelity and the significance of editing by mitochondrial aaRSs have been unclear. Here, we show that mammalian cells critically depended on the editing of mitochondrial threonyl-tRNA synthetase (mtThrRS, encoded by Tars2), disruption of which accumulated Ser-tRNAThr and generated a large abundance of Thr-to-Ser misincorporated peptides in vivo. Such infidelity impaired mitochondrial translation and oxidative phosphorylation, causing oxidative stress and cell cycle arrest in the G0/G1 phase. Notably, reactive oxygen species (ROS) scavenging by N-acetylcysteine attenuated this abnormal cell proliferation. A mouse model of heart-specific defective mtThrRS editing was established. Increased ROS levels, blocked cardiomyocyte proliferation, contractile dysfunction, dilated cardiomyopathy, and cardiac fibrosis were observed. Our results elucidate that mitochondria critically require a high level of translational accuracy at Thr codons and highlight the cellular dysfunctions and imbalance in tissue homeostasis caused by mitochondrial mistranslation.


Asunto(s)
Aminoacil-ARNt Sintetasas , Cardiomiopatías , Cardiopatías , Animales , Ratones , Especies Reactivas de Oxígeno , Puntos de Control del Ciclo Celular , Estrés Oxidativo , Mamíferos
7.
World J Clin Cases ; 11(22): 5316-5321, 2023 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-37621594

RESUMEN

BACKGROUND: The deterioration of thyroid health is involved in the progression of heart failure (HF). This is usually a lengthy process, so there are almost no reports on its rapid development. Here we report a case of a young male who rapidly developed hypothyroid cardiomyopathy secondary to radioactive iodine treatment, suggesting that severe HF might occur even after a short period of hypothyroidism. CASE SUMMARY: A 26-year-old man was referred to our hospital for HF presenting with dyspnea on exertion and chest discomfort lasting for 1 mo. He received radioactive iodine treatment for hyperthyroidism 1 year ago and had an almost normal echocardiogram 6 mo ago. Admission echocardiogram and cardiac magnetic resonance (CMR) revealed left ventricle (LV) global hypokinesia and severely depressed systolic function. In addition, late gadolinium enhancement indicated no obvious changes in the myocardium. Thyroid function tests showed decreased serum levels of thyroid hormone (TH) and elevated thyroid-stimulating hormone. Based on an exclusionary examination, the patient was diagnosed with hypothyroid cardiomyopathy and was started on replacement therapy. His HF symptoms were completely relieved during the six-month follow-up, and echocardiogram and CMR revealed recovered LV size and ejection fraction. CONCLUSION: This report demonstrates that severe fluctuations in TH levels may lead to acute HF, which can completely recover with timely thyroid hormone replacement. In addition, our findings highlight the importance of routinely detecting cardiac function in patients treated with radioactive iodine.

8.
Zhongguo Zhong Yao Za Zhi ; 48(14): 3890-3903, 2023 Jul.
Artículo en Chino | MEDLINE | ID: mdl-37475081

RESUMEN

This study aimed to explore the intervention effect of Chuanxiong-Chishao herb pair(CX-CS) on a myocardial infarction-atherosclerosis(MI-AS) mouse model and investigate its effect on the expression profile of circular RNAs(circRNAs)/long non-coding RNAs(lncRNAs) in ischemic myocardium and aorta. Sixty male ApoE~(-/-) mice were randomly assigned to a model group, high-, medium-, and low-dose CX-CS groups(7.8, 3.9, and 1.95 g·kg~(-1)), and a positive drug group(metoprolol 26 mg·kg~(-1) and simvastatin 5.2 mg·kg~(-1)), with 12 mice in each group. Male C57BL/6J mice were assigned to the sham group. The mice in the model group and the groups with drug intervention were fed on a high-fat diet for 10 weeks, followed by anterior descending coronary artery ligation. After that, the mice were fed on a high-fat diet for another two weeks to induce the MI-AS model. The mice in the sham group received normal feed, followed by sham surgery without coronary artery ligation. Mice in the groups with drug intervention received CX-CS or positive drug by gavage for four weeks from the 9th week of high-fat feeding, and those in the model group and the sham group received an equal volume of normal saline. Whole transcriptome sequencing was performed on the heart and aorta tissues of the medium-dose CX-CS group, the model group, and the sham group after administration. The results showed that the medium-and high-dose CX-CS groups showed improved cardiac function and reduced myocardial fibrosis area, and the medium-dose CX-CS group showed significantly reduced plaque area. CX-CS treatment could reverse the expression of circRNA_07227 and circRNA_11464 in the aorta of AS model and circRNA expression(such as circRNA_11505) in the heart of the MI model. Differentially expressed circRNAs between the CX-CS-treated mice and the model mice were mainly enriched in lipid synthesis, lipid metabolism, lipid transport, inflammation, and angiogenesis in the aorta, and in angiogenesis, blood pressure regulation, and other processes in the heart. CX-CS treatment could reverse the expression of lncRNAs such as ENSMUST00000162209 in the aorta of the AS model and TCONS_00002123 in the heart of the MI model. Differentially expressed lncRNAs between the CX-CS-treated mice and model mice were mainly enriched in lipid metabolism, angiogenesis, autophagy, apoptosis, and iron death in the aorta, and in angiogenesis, autophagy, and iron death in the heart. In summary, CX-CS can regulate the expression of a variety of circRNAs and lncRNAs, and its intervention mechanism in coronary heart disease may be related to the regulation of angiogenesis and inflammation in ischemic myocardium, as well as lipid metabolism, lipid transport, inflammation, angiogenesis in AS aorta.


Asunto(s)
Aterosclerosis , Infarto del Miocardio , ARN Largo no Codificante , Animales , Masculino , Ratones , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/genética , Lípidos , Ratones Endogámicos C57BL , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/genética , ARN Circular/genética , ARN Largo no Codificante/genética
9.
Zhongguo Zhong Yao Za Zhi ; 48(9): 2522-2529, 2023 May.
Artículo en Chino | MEDLINE | ID: mdl-37282881

RESUMEN

This study aimed to investigate the effects of Erxian Decoction(EXD)-containing serum on the proliferation and osteogenic differentiation of MC3T3-E1 cells under oxidative stress through BK channels. The oxidative stress model was induced in MC3T3-E1 cells by H_2O_2, and 3 mmol·L~(-1) tetraethylammonium(TEA) chloride was used to block the BK channels in MC3T3-E1 cells. MC3T3-E1 cells were divided into a control group, a model group, an EXD group, a TEA group, and a TEA+EXD group. After MC3T3-E1 cells were treated with corresponding drugs for 2 days, 700 µmol·L~(-1) H_2O_2 was added for treatment for another 2 hours. CCK-8 assay was used to detect cell proliferation activity. The alkaline phosphatase(ALP) assay kit was used to detect the ALP activity of cells. Western blot and real-time fluorescence-based quantitative PCR(RT-qPCR) were used to detect protein and mRNA expression, respectively. Alizarin red staining was used to detect the mineralization area of osteoblasts. The results showed that compared with the control group, the model group showed significantly blunted cell proliferation activity and ALP activity, reduced expression of BK channel α subunit(BKα), collagen Ⅰ(COL1), bone morphogenetic protein 2(BMP2), osteoprotegerin(OPG), and phosphorylated Akt, decreased mRNA expression levels of Runt-related transcription factor 2(RUNX2), BMP2, and OPG, and declining area of calcium nodules. EXD-containing serum could significantly potentiate the cell proliferation activity and ALP activity, up-regulate the protein expression of BKα, COL1, BMP2, OPG, and phosphorylated Akt, and forkhead box protein O1(FoxO1), promote the mRNA expression of RUNX2, BMP2, and OPG, and enlarge the area of calcium nodules. However, BK channel blockage by TEA reversed the effects of EXD-containing serum in promoting the protein expression of BKα, COL1, BMP2, OPG, and phosphorylated Akt and FoxO1, increasing the mRNA expression of RUNX2, BMP2, and OPG, and enlarging the area of calcium nodules. EXD-containing serum could improve the proliferation activity, osteogenic differentiation, and mineralization ability of MC3T3-E1 cells under oxidative stress, which might be related to the regulation of BK channels and downstream Akt/FoxO1 signaling pathway.


Asunto(s)
Diferenciación Celular , Subunidad alfa 1 del Factor de Unión al Sitio Principal , Canales de Potasio de Gran Conductancia Activados por el Calcio , Osteogénesis , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Subunidad alfa 1 del Factor de Unión al Sitio Principal/farmacología , Canales de Potasio de Gran Conductancia Activados por el Calcio/genética , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo , Osteogénesis/efectos de los fármacos , ARN Mensajero/genética , Medicamentos Herbarios Chinos/farmacología , Expresión Génica/efectos de los fármacos , Animales , Ratones , Línea Celular
10.
Redox Biol ; 63: 102722, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37167879

RESUMEN

Aminoacyl-tRNA synthetases (aaRSs) are indispensable players in translation. Usually, two or three genes encode cytoplasmic and mitochondrial threonyl-tRNA synthetases (ThrRSs) in eukaryotes. Here, we reported that Caenorhabditis elegans harbors only one tars-1, generating cytoplasmic and mitochondrial ThrRSs via translational reinitiation. Mitochondrial tars-1 knockdown decreased mitochondrial tRNAThr charging and translation and caused pleotropic phenotypes of delayed development, decreased motor ability and prolonged lifespan, which could be rescued by replenishing mitochondrial tars-1. Mitochondrial tars-1 deficiency leads to compromised mitochondrial functions including the decrease in oxygen consumption rate, complex Ⅰ activity and the activation of the mitochondrial unfolded protein response (UPRmt), which contributes to longevity. Furthermore, deficiency of other eight mitochondrial aaRSs in C. elegans and five in mammal also caused activation of the UPRmt. In summary, we deciphered the mechanism of one tars-1, generating two aaRSs, and elucidated the biochemical features and physiological function of C. elegans tars-1. We further uncovered a conserved connection between mitochondrial translation deficiency and UPRmt.


Asunto(s)
Aminoacil-ARNt Sintetasas , Proteínas de Caenorhabditis elegans , Animales , Caenorhabditis elegans/metabolismo , Longevidad/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Respuesta de Proteína Desplegada , Aminoacil-ARNt Sintetasas/genética , Aminoacil-ARNt Sintetasas/metabolismo , Breas/metabolismo , ARN de Transferencia/metabolismo , Mamíferos/genética , Mamíferos/metabolismo
11.
J Biol Chem ; 299(5): 104704, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37059185

RESUMEN

Aminoacyl-tRNA synthetases (aaRSs) are essential components for mRNA translation. Two sets of aaRSs are required for cytoplasmic and mitochondrial translation in vertebrates. Interestingly, TARSL2 is a recently evolved duplicated gene of TARS1 (encoding cytoplasmic threonyl-tRNA synthetase) and represents the only duplicated aaRS gene in vertebrates. Although TARSL2 retains the canonical aminoacylation and editing activities in vitro, whether it is a true tRNA synthetase for mRNA translation in vivo is unclear. In this study, we showed that Tars1 is an essential gene since homozygous Tars1 KO mice were lethal. In contrast, when Tarsl2 was deleted in mice and zebrafish, neither the abundance nor the charging levels of tRNAThrs were changed, indicating that cells relied on Tars1 but not on Tarsl2 for mRNA translation. Furthermore, Tarsl2 deletion did not influence the integrity of the multiple tRNA synthetase complex, suggesting that Tarsl2 is a peripheral member of the multiple tRNA synthetase complex. Finally, we observed that Tarsl2-deleted mice exhibited severe developmental retardation, elevated metabolic capacity, and abnormal bone and muscle development after 3 weeks. Collectively, these data suggest that, despite its intrinsic activity, loss of Tarsl2 has little influence on protein synthesis but does affect mouse development.


Asunto(s)
Aminoacil-ARNt Sintetasas , Biosíntesis de Proteínas , Treonina-ARNt Ligasa , Animales , Ratones , Aminoacil-ARNt Sintetasas/metabolismo , ARN de Transferencia/metabolismo , Treonina-ARNt Ligasa/genética , Treonina-ARNt Ligasa/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo
12.
CNS Neurosci Ther ; 29 Suppl 1: 59-73, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36601656

RESUMEN

BACKGROUND: Diabetic cognitive dysfunction (DCD) is one of the most insidious complications of type 2 diabetes mellitus, which can seriously affect the ability to self-monitoring of blood glucose and the quality of life in the elderly. Previous pathological studies of cognitive dysfunction have focused on neuronal dysfunction, characterized by extracellular beta-amyloid deposition and intracellular tau hyperphosphorylation. In recent years, astrocytes have been recognized as a potential therapeutic target for cognitive dysfunction and important participants in the central control of metabolism. The disorder of gut microbiota and their metabolites have been linked to a series of metabolic diseases such as diabetes mellitus. The imbalance of intestinal flora has the effect of promoting the occurrence and deterioration of several diabetes-related complications. Gut microbes and their metabolites can drive astrocyte activation. AIMS: We reviewed the pathological progress of DCD related to the "gut microbiota-astrocyte" axis in terms of peripheral and central inflammation, intestinal and blood-brain barrier (BBB) dysfunction, systemic and brain energy metabolism disorders to deepen the pathological research progress of DCD and explore the potential therapeutic targets. CONCLUSION: "Gut microbiota-astrocyte" axis, unique bidirectional crosstalk in the brain-gut axis, mediates the intermediate pathological process of neurocognitive dysfunction secondary to metabolic disorders in diabetes mellitus.


Asunto(s)
Disfunción Cognitiva , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Humanos , Anciano , Microbioma Gastrointestinal/fisiología , Astrocitos , Diabetes Mellitus Tipo 2/complicaciones , Calidad de Vida , Disfunción Cognitiva/etiología
13.
J Ethnopharmacol ; 302(Pt A): 115887, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36328203

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Er-xian Decoction (EXD) is a well-known prescription widely used to prevent and treat climacteric syndrome and osteoporosis in China. BK channel positively affects osteoblast bone formation in vitro. However, it is still unclear whether the effect of EXD on promoting osteoblasts osteogenic differentiation is related to BK channel. AIM OF THE STUDY: The study is aimed at determining whether the EXD-containing serum promotes the proliferation of osteoblasts and their differentiation through BK channel. MATERIALS AND METHODS: The chemical compounds of EXD were analyzed by UPLC-Q-TOF/MS. An osteogenic induction medium (OM) was used to induce MC3T3-E1 cells' osteogenic differentiation. The effects of EXD-containing serum and tetraethylammonium (TEA) on the proliferation activity of Mc3t3-e1 cells were detected by CCK-8 assay. ALP activity was determined by an alkaline phosphatase kit. The protein expression (BMP2, OPG, and COL1) was analyzed by Western blot, and the mRNA expression (Runx2, OPG, and BMP2) was assessed by real-time PCR. Alizarin red was used to stain the mineralized region of osteoblasts. In addition, we analyzed the relationship between BK channel and its downstream PTEN/Akt/Foxo1 signaling pathway. RESULTS: 72 compounds were identified by UPLC-Q-TOF/MS analysis in EXD. Mangiferin, ferulic acid, berberine, and icariin were main active components of EXD. EXD-containing serum could enhance the cell viability of MC3T3-E1 cells by decreasing the expression of BKα protein. EXD-containing serum increased ALP activity and calcium nodule formation of Mc3t3-e1 cells, promoted the protein expression of BKα, COL1, BMP2, OPG, and the mRNA expression of RUNX2, OPG, and BMP2, however, these effects can be reversed after adding TEA. In addition, EXD-containing serum could upregulate phosphorylation of Akt and Foxo1 in osteogenic-induced Mc3t3-e1 cells, and lower the expression of PTEN. And these effects of EXD-containing serum could be reduced by TEA. CONCLUSIONS: The effect of EXD-containing serum on promoting cell proliferation and osteogenic differentiation of Mc3t3-e1 cells might be linked to the regulation of BK channel.


Asunto(s)
Subunidad alfa 1 del Factor de Unión al Sitio Principal , Osteogénesis , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo , Canales de Potasio de Gran Conductancia Activados por el Calcio/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Línea Celular , Diferenciación Celular , Osteoblastos , Proliferación Celular , Fosfatasa Alcalina/metabolismo , ARN Mensajero/metabolismo
14.
Zhongguo Zhong Yao Za Zhi ; 47(19): 5292-5298, 2022 Oct.
Artículo en Chino | MEDLINE | ID: mdl-36472036

RESUMEN

This study aims to investigate the effects and the underlying mechanism of Huangqi Shengmai Decoction(HQSMD) in the treatment of fatigue and myocardial injury in a joint rat model. Wistar rats were assigned into 4 groups: sham, model, diltiazem hydrochloride(positive control), and HQSMD. The joint model of fatigue and myocardial injury was established by 14-day exhausted swimming followed by high ligation of the left anterior descending coronary artery. The rats in the sham group underwent a sham operation without coronary artery ligation or swimming. Since the fourth day after the ligation, swimming was continued in the model group and the drug-treated groups for the following 4 weeks. Meanwhile, the rats in the positive control group and the HQSMD group were respectively administrated intragastrically with diltiazem hydrochloride(20 mg·kg~(-1)·d~(-1)) and HQSMD(0.95 g·kg~(-1)·d~(-1)) for 4 weeks, while the shams and the models were given the same volume of normal saline. The left ventricular ejection fraction(LVEF), left ventricular fractional shortening(LVFS), grip strength, and myocardial pathophysiological changes were measured to evaluate the anti-fatigue and cardioprotective effects of HQSMD. The protein levels of PTEN-induced putative kinase 1(PINK1) and parkin in the myocardium were measured by Western blot to preliminarily elucidate the mechanism of HQSMD in ameliorating myocardial injury by suppressing mitochondrial autophagy. Compared with the shams, the models showed weakened heart function(LVEF and LVFS, P<0.01), decreased grasping ability(P<0.05), elevated blood urea nitrogen(BUN) and aldosterone(ALD) levels(P<0.01), aggravated myocardial fibrosis and connective tissue hyperplasia(P<0.01), and up-regulated protein levels of PINK1(P<0.01) and parkin(P<0.05). Four-week treatment with HQSMD increased the LVEF and LVFS levels(P<0.01), enhanced the grip strength(P<0.01), reduced the serum levels of BUN(P<0.01) and ALD(P<0.05), alleviated the pathological injury and fibrosis in the myocardium(P<0.01), and down-regulated the protein levels of PINK1(P<0.01) and parkin(P<0.05) in heart tissue. The results demonstrate that HQSMD may alleviate myocardial fibrosis and protect myocardium by suppressing the excessive mitochondrial auto-phagic activity and reducing the excessively elevated ALD level, thereby ameliorating fatigue and myocardial injury.


Asunto(s)
Cardiomiopatías , Lesiones Cardíacas , Ratas , Animales , Función Ventricular Izquierda , Ratas Sprague-Dawley , Volumen Sistólico , Diltiazem/farmacología , Ratas Wistar , Fibrosis , Proteínas Quinasas , Ubiquitina-Proteína Ligasas
15.
Front Surg ; 9: 1025557, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36338621

RESUMEN

Background: Biochemical processes involved in complex skin diseases (skin cancers, psoriasis, and wound) can be identified by combining proteomics analysis and bioinformatics tools, which gain a next-level insight into their pathogenesis, diagnosis, and therapeutic targets. Methods: Articles were identified through a search of PubMed, Embase, and MEDLINE references dated to May 2022, to perform system data mining, and a search of the Web of Science (WoS) Core Collection was utilized to conduct a visual bibliometric analysis. Results: An increased trend line revealed that the number of publications related to proteomics utilized in skin diseases has sharply increased recent years, reaching a peak in 2021. The hottest fields focused on are skin cancer (melanoma), inflammation skin disorder (psoriasis), and skin wounds. After deduplication and title, abstract, and full-text screening, a total of 486 of the 7,822 outcomes met the inclusion/exclusion criteria for detailed data mining in the field of skin disease tooling with proteomics, with regard to skin cancer. According to the data, cell death, metabolism, skeleton, immune, and inflammation enrichment pathways are likely the major part and hotspots of proteomic analysis found in skin diseases. Also, the focuses of proteomics in skin disease are from superficial presumption to depth mechanism exploration within more comprehensive validation, from basic study to a combination or guideline for clinical applications. Furthermore, we chose skin cancer as a typical example, compared with other skin disorders. In addition to finding key pathogenic proteins and differences between diseases, proteomic analysis is also used for therapeutic evaluation or can further obtain in-depth mechanisms in the field of skin diseases. Conclusion: Proteomics has been regarded as an irreplaceable technology in the study of pathophysiological mechanism and/or therapeutic targets of skin diseases, which could provide candidate key proteins for the insight into the biological information after gene transcription. However, depth pathogenesis and potential clinical applications need further studies with stronger evidence within a wider range of skin diseases.

16.
Front Genet ; 13: 853471, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35547245

RESUMEN

The role of N6-methyladenosine (m6A)-associated long-stranded non-coding RNA (lncRNA) in pancreatic cancer is unclear. Therefore, we analysed the characteristics and tumour microenvironment in pancreatic cancer and determined the value of m6A-related lncRNAs for prognosis and drug target prediction. An m6A-lncRNA co-expression network was constructed using The Cancer Genome Atlas database to screen m6A-related lncRNAs. Prognosis-related lncRNAs were screened using univariate Cox regression; patients were divided into high- and low-risk groups and randomised into training and test groups. In the training group, least absolute shrinkage and selection operator (LASSO) was used for regression analysis and to construct a prognostic model, which was validated in the test group. Tumor mutational burden (TMB), immune evasion, and immune function of risk genes were analysed using R; drug sensitivity and potential drugs were examined using the Genomics of Drug Sensitivity in Cancer database. We screened 129 m6A-related lncRNAs; 17 prognosis-related m6A-related lncRNAs were obtained using multivariate analysis and three m6A-related lncRNAs (AC092171.5, MEG9, and AC002091.1) were screened using LASSO regression. Survival rates were significantly higher (p < 0.05) in the low-risk than in the high-risk group. Risk score was an independent predictor affecting survival (p < 0.001), with the highest risk score being obtained by calculating the c-index. The TMB significantly differed between the high- and low-risk groups (p < 0.05). In the high- and low-risk groups, mutations were detected in 61 of 70 samples and 49 of 71 samples, respectively, with KRAS, TP53, and SMAD4 showing the highest mutation frequencies in both groups. A lower survival rate was observed in patients with a high versus low TMB. Immune function HLA, Cytolytic activity, and Inflammation-promoting, T cell co-inhibition, Check-point, and T cell co-stimulation significantly differed in different subgroups (p < 0.05). Immune evasion scores were significantly higher in the high-risk group than in the low-risk group. Eight sensitive drugs were screened: ABT.888, ATRA, AP.24534, AG.014699, ABT.263, axitinib, A.443654, and A.770041. We screened m6A-related lncRNAs using bioinformatics, constructed a prognosis-related model, explored TMB and immune function differences in pancreatic cancer, and identified potential therapeutic agents, providing a foundation for further studies of pancreatic cancer diagnosis and treatment.

17.
World J Gastroenterol ; 28(7): 715-731, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35317276

RESUMEN

BACKGROUND: Methods for predicting the prognosis of patients undergoing surgery for recurrent hepatolithiasis after biliary surgery are currently lacking. AIM: To establish a nomogram to predict the prognosis of patients with recurrent hepatolithiasis after biliary surgery. METHODS: In this multicenter, retrospective study, data of consecutive patients in four large medical centers who underwent surgery for recurrent hepatolithiasis after biliary surgery were retrospectively analyzed. We constructed a nomogram to predict the prognosis of recurrent hepatolithiasis in a training cohort of 299 patients, following which we independently tested the nomogram in an external validation cohort of 142 patients. Finally, we used the concordance index (C-index), calibra-tion, area under curve, decision curve analysis, clinical impact curves, and visual fit indices to evaluate the accuracy of the nomogram. RESULTS: Multiple previous surgeries [2 surgeries: Odds ratio (95% confidence interval), 1.451 (0.719-2.932); 3 surgeries: 4.573 (2.015-10.378); ≥ 4 surgeries: 5.741 (1.347-24.470)], bilateral hepatolithiasis [1.965 (1.039-3.717)], absence of immediate clearance [2.398 (1.304-4.409)], neutrophil-to-lymphocyte ratio ≥ 2.462 [1.915 (1.099-3.337)], and albumin-to-globulin ratio ≤ 1.5 [1.949 (1.056-3.595)] were found to be independent factors influencing the prognosis. The nomogram constructed on the basis of these variables showed good reliability in the training (C-index: 0.748) and validation (C-index: 0.743) cohorts. Compared with predictions using traditional classification models, those using our nomogram showed better agreement with actual observations in the calibration curve for the probability of endpoints and the receiver operating characteristic curve. Dichloroacetate and clinical impact curves showed a larger net benefit of the nomogram. CONCLUSION: The nomogram developed in this study demonstrated superior performance and discriminative power compared to the three traditional classifications. It is easy to use, highly accurate, and shows excellent calibration.


Asunto(s)
Litiasis , Hepatopatías , Humanos , Nomogramas , Pronóstico , Reproducibilidad de los Resultados , Estudios Retrospectivos
18.
Nucleic Acids Res ; 49(14): 8309-8323, 2021 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-34268557

RESUMEN

tRNAs harbor the most diverse posttranscriptional modifications. The 3-methylcytidine (m3C) is widely distributed at position C32 (m3C32) of eukaryotic tRNAThr and tRNASer species. m3C32 is decorated by the single methyltransferase Trm140 in budding yeasts; however, two (Trm140 and Trm141 in fission yeasts) or three enzymes (METTL2A, METTL2B and METTL6 in mammals) are involved in its biogenesis. The rationale for the existence of multiple m3C32 methyltransferases and their substrate discrimination mechanism is hitherto unknown. Here, we revealed that both METTL2A and METTL2B are expressed in vivo. We purified human METTL2A, METTL2B, and METTL6 to high homogeneity. We successfully reconstituted m3C32 modification activity for tRNAThr by METT2A and for tRNASer(GCU) by METTL6, assisted by seryl-tRNA synthetase (SerRS) in vitro. Compared with METTL2A, METTL2B exhibited dramatically lower activity in vitro. Both G35 and t6A at position 37 (t6A37) are necessary but insufficient prerequisites for tRNAThr m3C32 formation, while the anticodon loop and the long variable arm, but not t6A37, are key determinants for tRNASer(GCU) m3C32 biogenesis, likely being recognized synergistically by METTL6 and SerRS, respectively. Finally, we proposed a mutually exclusive substrate selection model to ensure correct discrimination among multiple tRNAs by multiple m3C32 methyltransferases.


Asunto(s)
Conformación de Ácido Nucleico , ARN de Transferencia/genética , ARNt Metiltransferasas/genética , Anticodón/genética , Citidina/análogos & derivados , Citidina/genética , Humanos , ARN/genética , ARN de Transferencia/ultraestructura , Serina-ARNt Ligasa/genética , Especificidad por Sustrato
19.
Chem Commun (Camb) ; 57(55): 6780-6783, 2021 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-34137393

RESUMEN

We combined a microporous polymer backbone with an organic redox-active dopant to construct a reversible electrode system based on the conversion-(de)incorporation behaviour of the dopant. The correspondence between the reversible conversion-(de)incorporation mechanism of the dopant and the electrochemical performance of the designed electrode system was established by electrochemical quartz crystal microbalance and in situ Fourier transform infrared spectroscopy.

20.
Inorg Chem ; 60(3): 1344-1351, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33423464

RESUMEN

Systematic substituent variations on amidinate ligands bring delicate changes of CrN4 coordination in a family of chromium(II) complexes with the common formula of Cr(RNC(CH3)NR)2, where R = iPr (1), Cy (2), Dipp (Dipp = 2, 6-diisopropylphenyl) (3), and tBu (4). With the largest substituent group, 4 shows the largest distortion of the N4 coordination geometry from square-planar to seesaw shape, which leads to its field-induced single-molecule magnet (SMM) behavior. This is an indication that 4 has the strongest axial magnetic anisotropy and/or optimized magnetic relaxation process. Combined with high-frequency/field electron paramagnetic resonance (HF-EPR) experiments and ab initio calculations, we deduce that the smallest energy gap between ground 4Ψ0 and the first excited 4Ψ1 orbitals in 4 contributes the most to its strongest magnetic anisotropy. Moreover, the lower E value of 4 ensures its being a field-induced SMM. Specifically, the D and E values were found to be correlated to the dihedral angle between the ΔN1CrN2 and ΔN3CrN4 triangles, indicating that distortion from ideal square-planar geometry to the seesaw help increase axial magnetic anisotropy and suppress the transversal part. Thus, the study on this system not only expands the family of Cr(II)-based SMMs but also contributes to a deeper understanding of magneto-structural correlation in four-coordinate Cr(II) SMMs.

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