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1.
J Am Chem Soc ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38754389

RESUMO

The exploitation of carbon dioxide (CO2) as a sustainable, plentiful, and harmless C1 source for the catalytic synthesis of enantioenriched carboxylic acids has long been acknowledged as a pivotal task in synthetic chemistry. Herein, we present a current-driven nickel-catalyzed reductive carboxylation reaction with CO2 fixation, facilitating the formation of C(sp3)-C(sp2) bonds by circumventing the handling of moisture-sensitive organometallic reagents. This electroreductive protocol serves as a practical platform, paving the way for the synthesis of enantioenriched propargylic carboxylic acids (up to 98% enantiomeric excess) from racemic propargylic carbonates and CO2. The efficacy of this transformation is exemplified by its successful utilization in the asymmetric total synthesis of (S)-arundic acid, (R)-PIA, (S)-chizhine D, (S)-cochlearin G, and (S,S)-alexidine, thereby underscoring the potential of asymmetric electrosynthesis to achieve complex molecular architectures sustainably.

2.
Int J Mol Sci ; 25(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38474107

RESUMO

Rice (Oryza sativa L.) is the staple food for more than 50% of the world's population. Owing to its growth characteristics, rice has more than 10-fold the ability to enrich the carcinogen arsenic (As) than other crops, which seriously affects world food security. The consumption of rice is one of the primary ways for humans to intake As, and it endangers human health. Effective measures to control As pollution need to be studied and promoted. Currently, there have been many studies on reducing the accumulation of As in rice. They are generally divided into agronomic practices and biotechnological approaches, but simultaneously, the problem of using the same measures to obtain the opposite results may be due to the different species of As or soil environments. There is a lack of systematic discussion on measures to reduce As in rice based on its mechanism of action. Therefore, an in-depth understanding of the molecular mechanism of the accumulation of As in rice could result in accurate measures to reduce the content of As based on local conditions. Different species of As have different toxicity and metabolic pathways. This review comprehensively summarizes and reviews the molecular mechanisms of toxicity, absorption, transport and redistribution of different species of As in rice in recent years, and the agronomic measures to effectively reduce the accumulation of As in rice and the genetic resources that can be used to breed for rice that only accumulates low levels of As. The goal of this review is to provide theoretical support for the prevention and control of As pollution in rice, facilitate the creation of new types of germplasm aiming to develop without arsenic accumulation or within an acceptable limit to prevent the health consequences associated with heavy metal As as described here.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Humanos , Arsênio/metabolismo , Oryza/genética , Poluentes do Solo/metabolismo , Melhoramento Vegetal , Estruturas Vegetais/metabolismo , Solo , Grão Comestível/metabolismo
3.
Adv Mater ; 36(21): e2313076, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38340141

RESUMO

The practical application of lithium (Li) metal batteries is inhibited by accumulative Li dendrites and continuous active Li consumption during cycling, which results in a low Coulombic efficiency and short lifetime. Constructing artificial solid-electrolyte interphase (SEI) layer in Li anode, such as 2D covalent organic frameworks (COFs), is an effective strategy to restrain the formation of Li dendrites and improve cycling performance. However, the exploration of 3D COFs as protecting layers is rarely reported, because of the preconception that the interconnect pores in 3D COFs eventually cause Li dendrites in disordered direction. 3D crown ether-based COF with ffc topology as interphase layer, in which the crown ether units are arranged in parallel and vertical orientation along the electrode, is demonstrated. The strong coupling effect between the crown ether and Li+ accelerates Li+ diffusion kinetics and enables homogeneous Li+ flux, resulting in a high Li+ transference number of 0.85 and smooth Li deposition in 3D direction. Li/COF-Cu cells display a lower Li-nucleation overpotential (17.4 mV) and high average Coulombic efficiency of ≈98.6% during 340 cycles with COF incorporation. This work gives a new insight into designing COFs for energy storage systems.

4.
Reprod Biomed Online ; 48(4): 103685, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38324980

RESUMO

RESEARCH QUESTION: What role does programmed cell death 4 (PDCD4) play in premature ovarian insufficiency (POI)? DESIGN: A PDCD4 gene knockout (PDCD4-/-) mouse model was constructed, a POI mouse model was established similar to human POI with 4-vinylcyclohexene dioxide (VCD), a PDCD4-overexpressed adenovirus was designed and the regulatory role in POI in vitro and in vivo was investigated. RESULTS: PDCD4 expression was significantly increased in the ovarian granulosa cells of patients with POI (P ≤ 0.002 protein and mRNA) and mice with VCD-induced POI (P < 0.001 protein expression in both mouse ovaries and granulosa cells). In POI-induced mice model, PDCD4 knockouts significantly increased anti-Müllerian hormone, oestrodiol and numbers of developing follicles, and the PI3K-AKT-Bcl2/Bax signalling pathway is involved in it. CONCLUSION: The expression and regulation of PDCD4 significantly affects the POI pathology in a mouse model. This effect is closely related to the regulation of Bcl2/Bax and the activation of the PI3K-AKT signalling pathway.


Assuntos
Cicloexenos , Insuficiência Ovariana Primária , Animais , Feminino , Humanos , Camundongos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteína X Associada a bcl-2/metabolismo , Modelos Animais de Doenças , Fosfatidilinositol 3-Quinases/metabolismo , Insuficiência Ovariana Primária/induzido quimicamente , Insuficiência Ovariana Primária/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas de Ligação a RNA/genética
5.
Talanta ; 272: 125784, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38364555

RESUMO

Fat mass and obesity-associated protein (FTO) is a crucial eraser of RNA N6- methyladenosine (m6A) modification, and abnormal FTO expression level is implicated in pathogenesis of numerous cancers. Herein, we demonstrate the construction of a label-free fluorescent biosensor for homogeneous detection of m6A eraser FTO in breast cancer tissues. When FTO is present, it specifically erases the methyl group in m6A, inducing the cleavage of demethylated DNA by endonuclease DpnII and the generation of a single-stranded DNA (ssDNA) with a 3'-hydroxyl group. Subsequently, terminal deoxynucleotidyl transferase (TdT) promotes the incorporation of dTTPs into the ssDNA to obtain a long polythymidine (T) DNA sequence. The resultant long poly (T) DNA sequence can act as a template to trigger hyperbranched strand displacement amplification (HSDA), yielding numerous DNA fragments that may be stained by SYBR Gold to produce an enhanced fluorescence signal. This biosensor processes ultrahigh sensitivity with a detection limit of 1.65 × 10-10 mg/mL (2.6 fM), and it can detect the FTO activity in a single MCF-7 cell. Moreover, this biosensor can screen the FTO inhibitors, evaluate enzyme kinetic parameters, and discriminate the FTO expression levels in the tissues of breast cancer patients and healthy persons.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , DNA , DNA de Cadeia Simples/genética , RNA , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética
6.
ISME J ; 18(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38366066

RESUMO

Microorganisms living in soil maintain intricate interactions among themselves, forming the soil microbiota that influences the rhizosphere microbiome and plant growth. However, the mechanisms underlying the soil microbial interactions remain unclear. Streptomyces and Mesorhizobium are commonly found in soil and serve as plant growth-promoting rhizobacteria (PGPR). Here, we identified an unprecedented interaction between the colonies of red-soil-derived Streptomyces sp. FXJ1.4098 and Mesorhizobium sp. BAC0120 and referred to it as "proximity-based defensive mutualism (PBDM)." We found that metabolite-mediated iron competition and sharing between the two microorganisms were responsible for PBDM. Streptomyces sp. FXJ1.4098 produced a highly diffusible siderophore, desferrioxamine, which made iron unavailable to co-cultured Mesorhizobium sp. BAC0120, thereby inhibiting its growth. Streptomyces sp. FXJ1.4098 also released poorly diffusible iron-porphyrin complexes, which could be utilized by Mesorhizobium sp. BAC0120, thereby restoring the growth of nearby Mesorhizobium sp. BAC0120. Furthermore, in ternary interactions, the PBDM strategy contributed to the protection of Mesorhizobium sp. BAC0120 close to Streptomyces sp. FXJ1.4098 from other microbial competitors, resulting in the coexistence of these two PGPR. A scale-up pairwise interaction screening suggested that the PBDM strategy may be common between Mesorhizobium and red-soil-derived Streptomyces. These results demonstrate the key role of iron in complex microbial interactions and provide novel insights into the coexistence of PGPR in soil.


Assuntos
Mesorhizobium , Streptomyces , Simbiose , Streptomyces/genética , Ferro , Mesorhizobium/genética , Rizosfera , Solo , Microbiologia do Solo , Raízes de Plantas
7.
Food Funct ; 14(23): 10347-10361, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37930368

RESUMO

Liver fibrosis (LF) is an important reparative process in response to acute or chronic hepatic injury, which has the potential to advance towards cirrhosis and hepatocellular carcinoma. Dietary naringin consumption contributes to protection against LF in animal studies, while the exact protective mechanism of naringin remains unclear. This study aimed to investigate the molecular mechanisms behind the potential protective effect of naringin against TAA-induced LF in zebrafish. In this study, we utilized zebrafish to create the LF model and investigate the therapeutic mechanism of naringin. Firstly, we evaluated the changes in hepatic fibrosis and lipid accumulation in the liver following naringin treatment with oil red O, Nile red, and Sirius red and immunohistochemistry. In addition, we employed an ROS probe to directly measure oxidative stress and monitor inflammatory cell migration in a zebrafish transgenic line. Morpholino was used in the knockdown of IDO1 in order to verify its vital role in LF. Our findings demonstrated that naringin exhibited anti-inflammatory and anti-fibrotic action in conjunction with a reversal in lipid accumulation, oxidative stress and suppression of macrophage infiltration and activation of hepatic stellate cells. Furthermore, the results showed that the antifibrotic effect of naringin was removed upon IDO1 knockdown, proving that naringin exerts a protective effect by regulating IDO1. Naringin demonstrates remarkable protective effects against LF, effectively counteracting inflammation and hepatic steatosis in zebrafish liver. These findings suggest that naringin may function as an effective IDO1 inhibitor, holding the potential for clinical translation as a therapeutic agent for the treatment of LF.


Assuntos
Metabolismo dos Lipídeos , Peixe-Zebra , Animais , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , Fígado/metabolismo , Fibrose , Células Estreladas do Fígado/metabolismo , Lipídeos/farmacologia
8.
Anal Chim Acta ; 1279: 341796, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37827689

RESUMO

The METTL3/14 complex is an important RNA N6-Methyladenosine (m6A) methyltransferase in organisms, and the abnormal METTL3/14 complex activity is associated with the pathogenesis and various cancers. Sensitive detection of METTL3/14 complex is essential to tumor pathogenesis study, cancer diagnosis, and anti-cancer drug discovery. However, traditional methods for METTL3/14 complex assay suffer from poor specificity, costly antibodies, unstable RNA substrates, and low sensitivity. Herein, we construct a single quantum dot (QD)-based förster resonance energy transfer (FRET) biosensor for sensitive detection of METTL3/14 complex activity. In the presence of METTL3/14 complex, it catalyzes the methylation of adenine in the substrate probe, leading to the formation of m6A that protects the substrate probes from MazF-mediated cleavage. The hybridization of methylated DNA substrate with biotinylated capture probe initiates polymerization reaction to obtain a biotinylated double-stranded DNA (dsDNA) with the incorporation of numerous Cy5 fluorophores. Subsequently, the Cy5-incorporated dsDNA can self-assembly onto the 605QD surface to form the 605QD-dsDNA-Cy5 nanostructure, causing FRET between 605QD donor and Cy5 acceptor. This biosensor has excellent sensitivity with a limit of detection (LOD) of 3.11 × 10-17 M, and it can measure the METTL3/14 complex activity in a single cell. Moreover, this biosensor can be used to evaluate the METTL3/14 complex kinetic parameters and screen potential inhibitors. Furthermore, it can differentiate the METTL3/14 complex expression in healthy human tissues and breast cancer patient tissues, providing a powerful tool for cancer pathogenesis study, clinical diagnosis, prognosis monitoring, and drug discovery.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Pontos Quânticos , Humanos , Feminino , Pontos Quânticos/química , Neoplasias da Mama/diagnóstico , DNA/química , Metiltransferases , RNA
9.
Front Immunol ; 14: 1118449, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36742318

RESUMO

Non-alcoholic fatty liver disease (NAFLD) has now become the leading chronic liver disease worldwide with lifestyle changes. This may lead to NAFLD becoming the leading cause of end-stage liver disease in the future. To date, there are still no effective therapeutic drugs for NAFLD. An in-depth exploration of the pathogenesis of NAFLD can help to provide a basis for new therapeutic agents or strategies. As the most important immune cells of the liver, macrophages play an important role in the occurrence and development of liver inflammation and are expected to become effective targets for NAFLD treatment. Programmed cell death (PCD) of macrophages plays a regulatory role in phenotypic transformation, and there is also a certain connection between different types of PCD. However, how PCD regulates macrophage polarization has still not been systematically elucidated. Based on the role of lipid metabolic reprogramming in macrophage polarization, PCD may alter the phenotype by regulating lipid metabolism. We reviewed the effects of macrophages on inflammation in NAFLD and changes in their lipid metabolism, as well as the relationship between different types of PCD and lipid metabolism in macrophages. Furthermore, interactions between different types of PCD and potential therapeutic agents targeting of macrophages PCD are also explored.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Metabolismo dos Lipídeos , Macrófagos/metabolismo , Inflamação/metabolismo , Apoptose
10.
Microbiol Spectr ; : e0385222, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36847561

RESUMO

Lasalocid, a representative polyether ionophore, has been successfully applied in veterinary medicine and animal husbandry and also displays promising potential for cancer therapy. Nevertheless, the regulatory system governing lasalocid biosynthesis remains obscure. Here, we identified two conserved (lodR2 and lodR3) and one variable (lodR1, found only in Streptomyces sp. strain FXJ1.172) putative regulatory genes through a comparison of the lasalocid biosynthetic gene cluster (lod) from Streptomyces sp. FXJ1.172 with those (las and lsd) from Streptomyces lasalocidi. Gene disruption experiments demonstrated that both lodR1 and lodR3 positively regulate lasalocid biosynthesis in Streptomyces sp. FXJ1.172, while lodR2 plays a negative regulatory role. To unravel the regulatory mechanism, transcriptional analysis and electrophoretic mobility shift assays (EMSAs) along with footprinting experiments were performed. The results revealed that LodR1 and LodR2 could bind to the intergenic regions of lodR1-lodAB and lodR2-lodED, respectively, thereby repressing the transcription of the lodAB and lodED operons, respectively. The repression of lodAB-lodC by LodR1 likely boosts lasalocid biosynthesis. Furthermore, LodR2 and LodE constitute a repressor-activator system that senses changes in intracellular lasalocid concentrations and coordinates its biosynthesis. LodR3 could directly activate the transcription of key structural genes. Comparative and parallel functional analyses of the homologous genes in S. lasalocidi ATCC 31180T confirmed the conserved roles of lodR2, lodE, and lodR3 in controlling lasalocid biosynthesis. Intriguingly, the variable gene locus lodR1-lodC from Streptomyces sp. FXJ1.172 seems functionally conserved when introduced into S. lasalocidi ATCC 31180T. Overall, our findings demonstrate that lasalocid biosynthesis is tightly controlled by both conserved and variable regulators, providing valuable guidance for further improving lasalocid production. IMPORTANCE Compared to its elaborated biosynthetic pathway, the regulation of lasalocid biosynthesis remains obscure. Here, we characterize the roles of regulatory genes in lasalocid biosynthetic gene clusters of two distinct Streptomyces species and identify a conserved repressor-activator system, LodR2-LodE, which could sense changes in the concentration of lasalocid and coordinate its biosynthesis with self-resistance. Furthermore, in parallel, we verify that the regulatory system identified in a new Streptomyces isolate is valid in the industrial lasalocid producer and thus applicable for the construction of high-yield strains. These findings deepen our understanding of regulatory mechanisms involved in the production of polyether ionophores and provide novel clues for the rational design of industrial strains for scaled-up production.

11.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36430160

RESUMO

Anticancer peptide (ACP) is a short peptide with less than 50 amino acids that has been discovered in a variety of foods. It has been demonstrated that traditional Chinese medicine or food can help treat cancer in some cases, which suggests that ACP may be one of the therapeutic ingredients. Studies on the anti-cancer properties of Sanghuangporus sanghuang have concentrated on polysaccharides, flavonoids, triterpenoids, etc. The function of peptides has not received much attention. The purpose of this study is to use computer mining techniques to search for potential anticancer peptides from 62 proteins of Sanghuang. We used mACPpred to perform sequence scans after theoretical trypsin hydrolysis and discovered nine fragments with an anticancer probability of over 0.60. The study used AlphaFold 2 to perform structural modeling of the first three ACPs discovered, which had blast results from the Cancer PPD database. Using reverse docking technology, we found the target proteins and interacting residues of two ACPs with an unknown mechanism. Reverse docking results predicted the binding modes of the ACPs and their target protein. In addition, we determined the active part of ACPs by quantum chemical calculation. Our study provides a framework for the future discovery of functional peptides from foods. The ACPs discovered have the potential to be used as drugs in oncology clinical treatment after further research.


Assuntos
Antineoplásicos , Neoplasias , Triterpenos , Humanos , Antineoplásicos/uso terapêutico , Peptídeos/química , Neoplasias/tratamento farmacológico , Proteínas/uso terapêutico , Triterpenos/uso terapêutico
12.
Orthop Surg ; 14(9): 2210-2218, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35979987

RESUMO

OBJECTIVE: The bone mass around the prosthesis plays an important role in the stability of the prosthesis. This study aimed to assess the effect of postoperative activity on bone mineral density (BMD) in the proximal tibia 5 years after total knee arthroplasty (TKA). To provide a scientific guidance for postoperative functional exercise. METHODS: 110 patients underwent unilateral primary TKA were divided into three groups based on the University of California Los Angeles (UCLA) activity scale: low activity group (LA group, UCLA = 4, 5); medium activity group (MA group, UCLA = 6, 7); and high activity group (HA group, UCLA = 8, 9). The primary observation was a comparison of the BMD and BMD change percentage (ΔBMD (%)) in the periprosthetic tibia among the LA, MA and HA groups at 1 year, 3 years and 5 years. The secondary observations were radiographic evaluation (prosthetic stability, periprosthetic fractures, aseptic loosening and periprosthetic joint infection) and clinical evaluation (Knee Society Score (KSS), visual analogue score scores and range of motion (ROM)). A one-way ANOVA was used to compare the clinical scores and BMD among the three groups. RESULTS: The BMD of medial region decreased by 10.80%, 12.64%, 13.61% at 1, 3, and 5 years respectively; these were 5.72%, 6.26%, 7.83% in lateral region and 1.42%, 1.78%, 3.28% in diaphyseal region. For medial metaphyseal region, the BMD of the MA group was significantly greater than that of the LA and HA groups at 1 and 3 years (108.9 ± 5.2 vs. 106.1 ± 6.69 vs. 105.4 ± 5.2 and 108.5 ± 6.0 vs. 101.2 ± 6.76 vs. 103.0 ± 6.8, P < 0.01 and P < 0.001), and the BMD changes (ΔBMD (%)) in the MA group were significantly smaller than those in the LA and HA groups (8.75 ± 5.36 vs. 11.92 ± 5.49 vs. 12.70 ± 5.21 and 9.11 ± 5.11 vs. 16.04 ± 4.79 vs. 14.82 ± 4.26, P < 0.01 and P < 0.001). Regarding secondary observations, all of the prostheses were assessed as stable, without periprosthetic fractures, aseptic loosening and periprosthetic joint infection. Regarding KSS scores, there was no significant difference among the three groups. However, the VAS and ROM of the HA group were better than those of the MA and LA groups (1.65 ± 0.79 vs. 2.63 ± 0.77 vs. 3.00 ± 1.17, p < 0.001, and 111.90 ± 9.17 vs. 110.20 ± 6.78 vs. 102.90 ± 8.48, P < 0.001). CONCLUSION: Medium activity prevented periprosthetic bone loss in the medial metaphyseal region of the tibia after posterior-stabilized TKA, and moderate-intensity exercise is recommended for patients after TKA to reduce periprosthetic bone loss.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Osteoartrite do Joelho , Fraturas Periprotéticas , Infecções Relacionadas à Prótese , Densidade Óssea , Seguimentos , Humanos , Articulação do Joelho , Osteoartrite do Joelho/cirurgia , Fraturas Periprotéticas/prevenção & controle , Fraturas Periprotéticas/cirurgia , Infecções Relacionadas à Prótese/cirurgia , Tíbia/cirurgia
13.
Chem Commun (Camb) ; 58(62): 8662-8665, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35822530

RESUMO

We have developed a simple and rapid mix-and-read assay for the sensitive detection of O6-methylguanine DNA methyltransferase (MGMT) activity based on exonuclease III-assisted signal amplification under completely isothermal conditions (37 °C). This method is very simple and rapid (60 min) with ultrahigh sensitivity and good specificity, and it can detect MGMT activity at the single-cell level. Moreover, this method can be applied for the screening of MGMT inhibitors and the discrimination of MGMT in different cancer cells.


Assuntos
Guanina , O(6)-Metilguanina-DNA Metiltransferase , DNA , Guanina/análogos & derivados , O(6)-Metilguanina-DNA Metiltransferase/genética
14.
J Mater Chem B ; 10(17): 3277-3284, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35362489

RESUMO

DNA glycosylases are engaged in the base excision repair process and play a vital role in maintaining genomic integrity. It remains a challenge for multiplexed detection of DNA glycosylases in cancer cells. Herein, we demonstrate the construction of a dephosphorylation-mediated chemiluminescent biosensor for multiplexed detection of human alkyladenine DNA glycosylase (hAAG) and uracil DNA glycosylase (UDG) in cancer cells. In this biosensor, the generation of chemiluminescence signals relies on the dephosphorylation of 3-(2'-spiroadamantyl)-4-methoxy-4-(3''-phosphoryloxyphenyl)-1,2-dioxetane (AMPPD) catalyzed by alkaline phosphatase (ALP). We design a bifunctional double-stranded DNA (dsDNA) substrate, a biotin-labelled poly-(T) probe, and two capture probes for the hAAG and UDG assay. This assay involves four steps including (1) the cleavage of the bifunctional dsDNA substrate induced by DNA glycosylases, (2) the recognition of the 3'-OH terminus of the primer by TdT and the subsequent TdT-mediated polymerization reaction, (3) the construction of the AuNPs-dsDNA-ALP nanostructures, and (4) the streptavidin-alkaline phosphatase (SA-ALP)-initiated dephosphorylation of AMPPD for the generation of an enhanced chemiluminescence signal. By taking advantage of the unique features of TdT-mediated polymerization and the intrinsic superiority of the ALP-AMPPD-based chemiluminescence system, this biosensor exhibits good specificity and high sensitivity with a detection limit of 1.53 × 10-6 U mL-1 for hAAG and 1.77 × 10-6 U mL-1 for UDG, and it can even quantify multiple DNA glycosylases at the single-cell level. Moreover, this biosensor can be applied for the measurement of kinetic parameters and the screening of DNA glycosylase inhibitors, holding great potential in DNA damage-related biomedical research and disease diagnostics.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Neoplasias , Fosfatase Alcalina , DNA/química , Ouro , Humanos , Uracila-DNA Glicosidase
15.
Rheumatology (Oxford) ; 62(1): 373-383, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-35412608

RESUMO

OBJECTIVES: This study aimed to investigate the high-resolution CT (HRCT) characteristics of anti-melanoma differentiation-associated gene 5 (MDA5) antibody positive dermatomyositis-associated interstitial lung disease (anti-MDA5 DM-ILD), and to clarify the underlying mechanisms of the clinical phenomenon. METHODS: Clinical data and HRCT patterns were compared between anti-MDA5 DM-ILD (n = 32) and antisynthetase syndrome-associated ILD (ASS-ILD) (n = 29). RNA sequencing of whole-blood samples from the two groups, and in vitro experiments using human embryonic lung fibroblasts (HELFs) were conducted to explore the potential mechanisms of the clinical findings. RESULTS: The anti-MDA5 DM-ILD subset had a significantly higher incidence of rapidly progressive ILD (RPILD) than ASS-ILD (65.6% vs 37.9%; P = 0.031). The relative percentage of the lung fibrosis HRCT pattern was significantly lower in the anti-MDA5 DM-ILD group, especially the RPILD subgroup (P = 0.013 and 0.003, respectively). RNA sequencing detected the upregulated genes including interferon-induced helicase C domain 1 (encoding MDA5), and a trend towards downregulated expression of TGF-ß signalling components in anti-MDA5 DM-ILD. In vitro culture of HELFs revealed that upregulated expression of MDA5 in HELFs was correlated with the downregulated expression of alpha smooth muscle actin, connective tissue growth factor, collagen I and collagen III by suppressing the TGF-ß signalling pathway. CONCLUSIONS: Anti-MDA5 DM-ILD patients have significantly less lung fibrosis and elevated MDA5 expression. The upregulated expression of MDA5 has relations with the suppression of the pro-fibrotic function of fibroblasts via the TGF-ß signalling pathway, which may partially explain the mechanism of the clinical phenomenon.


Assuntos
Dermatomiosite , Doenças Pulmonares Intersticiais , Fibrose Pulmonar , Humanos , Autoanticorpos , Progressão da Doença , Helicase IFIH1 Induzida por Interferon/genética , Prognóstico , Fibrose Pulmonar/complicações , Estudos Retrospectivos
16.
EBioMedicine ; 78: 103964, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35339897

RESUMO

BACKGROUND: Clonal haematopoiesis driven by mutations in DNMT3A or TET2 has recently been identified as a new risk factor for cardiovascular disease. Experimental studies suggest that these mutations may enhance inflammation which accelerates the disease progression. We aim to investigate the prevalence of mutations in DNMT3A and TET2 and their association with prognosis of patients with ST-segment elevation myocardial infarction (STEMI). METHODS: Targeted deep sequencing for DNMT3A and TET2 and inflammatory cytokines (IL-1ß, IL-6, TNF-α, INF-γ) were analyzed in 485 patients with STEMI. Major adverse cardiac events (MACE) was a composite of death, myocardial infarction, stroke, or hospitalization due to heart failure. FINDINGS: Patients carrying DNMT3A- or TET2-CH-driver mutations with a variant allele frequency (VAF) ≥2% were found in 12.4% (60 of 485) of STEMI patients and experienced an increased incidence of the death (30.9% vs 15.5%, P = 0.001) and MACE (44.5% vs 21.8%, P < 0.001) compared to those who did not, during a median follow up of 3.0 (interquartile range: 2.4-3.4) years. After adjusting for confounders, mutation remained an independent predictor of death (HR = 1.967, 95% CI 1.103-3.507, P = 0.022) and MACE (HR = 1.833, 95% CI 1.154-2.912, P = 0.010). Concentrations of plasma IL-1ß (P = 0.010) and IL-6 (P = 0.011) were significantly elevated in DNMT3A/TET2 VAF≥2% group. INTERPRETATION: DNMT3A- or TET2-CH-driver mutations with a VAF≥2% were observed in over 10% STEMI patients, and were significantly associated with poorer prognosis, which might be explained by higher levels of inflammatory cytokines in mutations carriers. FUNDING: National Natural Science Foundation of China; National Key R&D Program of China.


Assuntos
DNA Metiltransferase 3A , Proteínas de Ligação a DNA , Dioxigenases , Infarto do Miocárdio com Supradesnível do Segmento ST , Hematopoiese Clonal , Citocinas , DNA Metiltransferase 3A/genética , Proteínas de Ligação a DNA/genética , Dioxigenases/genética , Humanos , Mutação , Prevalência , Prognóstico , Proteínas Proto-Oncogênicas/genética , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/genética
17.
Circ Genom Precis Med ; 14(5): e003401, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34601892

RESUMO

BACKGROUND: The presence of variants in OBSCN was identified to be linked to hypertrophic cardiomyopathy (HCM), but whether OBSCN truncating variants were associated with HCM remained unknown. METHODS: Whole-exome sequencing was performed in 986 patients with HCM and 761 non-HCM controls to search for OBSCN truncating variants, and the result was tested in a replication cohort consisting of 529 patients with HCM and 307 controls. The association of the OBSCN truncating variants with baseline characteristics and prognosis of patients with HCM were ascertained. RESULTS: There were 28 qualifying truncating variants in the OBSCN gene detected in 26 (2.6%) patients with HCM and 6 (0.8%) controls. The OBSCN truncating variants were more prevalent in patients with HCM than controls (odds ratio, 3.4, P=0.004). This association was confirmed in the replication cohort (odds ratio, 3.8, P=0.024). The combined effects of the two cohorts estimated the odds ratio to be 3.58 (P<0.001). Patients with or without OBSCN truncating variants shared similar demographic and echocardiographic variables at baseline. During 3.3±2.4 years (4795 patient-years) follow-up, the patients with OBSCN truncating variants were more likely to experience cardiovascular death (adjusted hazard ratio, 3.1 [95% CI, 1.40-6.70], P=0.005) and all-cause death (adjusted hazard ratio, 2.63 [95% CI, 1.21-5.71], P=0.015). CONCLUSIONS: Our data indicated that OBSCN truncating variants contributed to the disease-onset of HCM, and increased the risk of malignant events in patients with HCM.


Assuntos
Cardiomiopatia Hipertrófica/genética , Sequenciamento do Exoma , Proteínas Serina-Treonina Quinases/genética , Fatores de Troca de Nucleotídeo Guanina Rho/genética , Adulto , Cardiomiopatia Hipertrófica/mortalidade , Seguimentos , Humanos , Pessoa de Meia-Idade
18.
Yale J Biol Med ; 93(4): 529-537, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33005117

RESUMO

Polycystic ovary syndrome (PCOS) is a common endocrinopathy affecting 46XX individuals of reproductive age. Cardinal features of PCOS include hyperandrogenism, irregular periods, and insulin resistance. Pathogenesis is unclear but likely involves hypothalamic, pituitary, or ovarian abnormalities leading to increased androgen production. In addition, alternative insulin signaling pathways are activated to preserve ovarian sensitivity to insulin while other "classical" tissues (e.g. liver, adipose, muscle) are insulin resistant. Treatment targets specific symptoms and the most common regimens include weight loss, metformin, oral contraceptives, anti-androgen compounds, and fertility treatments. Observations of individuals with gene mutations affecting androgen metabolism suggest that androgens may influence the development of gender identity. We reviewed studies exploring the relationship between gender identity and PCOS to further elucidate this relationship. Rates of PCOS in hormone-naïve transmasculine (TM) individuals appear to be higher than in the general population as cited by small, early studies using convenience samples and inconsistent criteria for PCOS. A more recent, larger study using established guidelines for PCOS did not show this to be true. Further, other studies show that although PCOS patients are less likely to identify with a traditional feminine gender scheme compared to age-matched peers, the prevalence of gender incongruence in PCOS patients is not higher than in the general population. Larger systematic studies with control groups using modern diagnostic criteria for both PCOS and gender incongruence are needed to clarify the relationship between PCOS and gender identity.


Assuntos
Disforia de Gênero , Hiperandrogenismo , Resistência à Insulina , Síndrome do Ovário Policístico , Androgênios , Feminino , Identidade de Gênero , Humanos , Masculino
19.
Front Neurol ; 11: 707, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765412

RESUMO

Background: The glymphatic pathway has been shown to be impaired in traumatic brain injury (TBI). Omega-3 polysaturated fatty acids (Omega-3, PUFAs) are involved in the clearance of amyloid-ß through the glymphatic system and this effect is Aquaporin-4 (AQP4) dependent. We hypothesize that Omega-3 PUFAs can alleviate neurological impairment in TBI by protecting the glymphatic pathway. Methods: We pretreated mice with Omega-3 PUFAs rich fish oil and introduced TBI in the mice. Neurological functions were assessed through the modified neurological severity score (mNSS) system and Rota-rod test. Aß42 levels and radioisotope clearance were examined to determine the function of glymphatic system. AQP4 protein and mRNA expressions and its polarity were examined in fish oil treated TBI mice or control mice. Finally, the integrity of blood-brain barrier was determined by Evans blue extravasation and measurement of tight junction proteins (ZO-1 and Occludin) levels. Results: TBI surgery induced significant neurological functional impairment, Omega-3 PUFAs attenuated TBI-induced neurological impairment, as evidenced by reduced mNSS, improved performance in the Rota-rod test. Furthermore, Omega-3 PUFAs improved glymphatic clearance after induction of TBI in mice, reduced Aß42 accumulation, partially restored the clearance of both 3H-mannitol and 14C-Inulin. Omega-3 PUFAs also suppressed AQP4 expression and partially prevented loss of AQP4 polarity in mice undergoing TBI. Finally, Omega-3 PUFAs protected mice from TBI induced blood-brain barrier disruption. Conclusion: Omaga-3 PUFAs attenuate neurological function by partially restoring the AQP4 dependent glymphatic system in mice with TBI.

20.
Eur J Endocrinol ; 183(1): 21-30, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32348956

RESUMO

OBJECTIVE: The neurophysiological mechanisms underlying cognitive dysfunction in primary hyperparathyroidism (PHPT) and the brain regions affected are not clear. We assessed neural activation during cognitive testing (matrix reasoning, paired associates, and logical memory) using functional MRI (fMRI) in 23 patients with PHPT and 23 healthy controls. A subset with PHPT was re-assessed 6 months post-parathyroidectomy (PTX). DESIGN: This is an observational study comparing neural activation by fMRI in patients with PHPT to normative controls. Postmenopausal women were studied at a tertiary referral center. RESULTS: There were no between-group differences in cognitive task performance. Patients with PHPT had lower neural activation vs controls (max Z = 4.02, all P < 0.01) during matrix reasoning in brain regions involved in executive function (left frontal lobe (k = 57) and right medial frontal gyrus (k = 72)) and motor function (right precentral gyrus (k = 51)). During paired associates (verbal memory), those with PHPT had greater activation in the right inferior parietal lobule (language/mathematical operations; k = 65, P < 0.01). Greater activation in this region bilaterally correlated with higher PTH (k = 96, P < 0.01). Post-PTX, activation decreased during matrix reasoning, but in different regions than those affected pre-PTX. CONCLUSIONS: PHPT is associated with differences in task-related neural activation patterns, but no difference in cognitive performance. While this may indicate compensation to maintain the same cognitive function, there was no clear improvement in neural activation after PTX. Larger, longitudinal studies that include PHPT patients followed without surgery are needed to determine if PTX could prevent worsening of altered neural activation patterns in PHPT.


Assuntos
Encéfalo/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Hiperparatireoidismo Primário/fisiopatologia , Idoso , Mapeamento Encefálico , Disfunção Cognitiva/complicações , Feminino , Humanos , Hiperparatireoidismo Primário/complicações , Hiperparatireoidismo Primário/cirurgia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Testes Neuropsicológicos , Paratireoidectomia
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