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1.
Mol Cell ; 84(9): 1637-1650.e10, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38604171

RESUMO

Long interspersed element-1 (LINE-1 or L1) comprises 17% of the human genome, continuously generates genetic variations, and causes disease in certain cases. However, the regulation and function of L1 remain poorly understood. Here, we uncover that L1 can enrich RNA polymerase IIs (RNA Pol IIs), express L1 chimeric transcripts, and create contact domain boundaries in human cells. This impact of L1 is restricted by a nuclear matrix protein scaffold attachment factor B (SAFB) that recognizes transcriptionally active L1s by binding L1 transcripts to inhibit RNA Pol II enrichment. Acute inhibition of RNA Pol II transcription abolishes the domain boundaries associated with L1 chimeric transcripts, indicating a transcription-dependent mechanism. Deleting L1 impairs domain boundary formation, and L1 insertions during evolution have introduced species-specific domain boundaries. Our data show that L1 can create RNA Pol II-enriched regions that alter genome organization and that SAFB regulates L1 and RNA Pol II activity to preserve gene regulation.


Assuntos
Elementos Nucleotídeos Longos e Dispersos , Proteínas de Ligação à Região de Interação com a Matriz , RNA Polimerase II , Receptores de Estrogênio , Transcrição Gênica , Humanos , RNA Polimerase II/metabolismo , RNA Polimerase II/genética , Elementos Nucleotídeos Longos e Dispersos/genética , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Proteínas de Ligação à Região de Interação com a Matriz/genética , Proteínas Associadas à Matriz Nuclear/metabolismo , Proteínas Associadas à Matriz Nuclear/genética , Regulação da Expressão Gênica , Ligação Proteica , Células HEK293 , Genoma Humano
2.
Nature ; 596(7872): 353-356, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34408333

RESUMO

On Earth's surface, there are only a handful of high-quality astronomical sites that meet the requirements for very large next-generation facilities. In the context of scientific opportunities in time-domain astronomy, a good site on the Tibetan Plateau will bridge the longitudinal gap between the known best sites1,2 (all in the Western Hemisphere). The Tibetan Plateau is the highest plateau on Earth, with an average elevation of over 4,000 metres, and thus potentially provides very good opportunities for astronomy and particle astrophysics3-5. Here we report the results of three years of monitoring of testing an area at a local summit on Saishiteng Mountain near Lenghu Town in Qinghai Province. The altitudes of the potential locations are between 4,200 and 4,500 metres. An area of over 100,000 square kilometres surrounding Lenghu Town has a lower altitude of below 3,000 metres, with an extremely arid climate and unusually clear local sky (day and night)6. Of the nights at the site, 70 per cent have clear, photometric conditions, with a median seeing of 0.75 arcseconds. The median night temperature variation is only 2.4 degrees Celsius, indicating very stable local surface air. The precipitable water vapour is lower than 2 millimetres for 55 per cent of the night.

3.
Proc Natl Acad Sci U S A ; 120(2): e2213528120, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36595700

RESUMO

Flow batteries are a promising energy storage solution. However, the footprint and capital cost need further reduction for flow batteries to be commercially viable. The flow cell, where electron exchange takes place, is a central component of flow batteries. Improving the volumetric power density of the flow cell (W/Lcell) can reduce the size and cost of flow batteries. While significant progress has been made on flow battery redox, electrode, and membrane materials to improve energy density and durability, conventional flow batteries based on the planar cell configuration exhibit a large cell size with multiple bulky accessories such as flow distributors, resulting in low volumetric power density. Here, we introduce a submillimeter bundled microtubular (SBMT) flow battery cell configuration that significantly improves volumetric power density by reducing the membrane-to-membrane distance by almost 100 times and eliminating the bulky flow distributors completely. Using zinc-iodide chemistry as a demonstration, our SBMT cell shows peak charge and discharge power densities of 1,322 W/Lcell and 306.1 W/Lcell, respectively, compared with average charge and discharge power densities of <60 W/Lcell and 45 W/Lcell, respectively, of conventional planar flow battery cells. The battery cycled for more than 220 h corresponding to >2,500 cycles at off-peak conditions. Furthermore, the SBMT cell has been demonstrated to be compatible with zinc-bromide, quinone-bromide, and all-vanadium chemistries. The SBMT flow cell represents a device-level innovation to enhance the volumetric power of flow batteries and potentially reduce the size and cost of the cells and the entire flow battery.


Assuntos
Líquidos Corporais , Brometos , Tamanho Celular , Fibras na Dieta , Zinco
4.
Plant J ; 120(1): 253-271, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39166483

RESUMO

Drought is one of the most important abiotic stresses, and seriously threatens plant development and productivity. Increasing evidence indicates that chromatin remodelers are pivotal for plant drought response. However, molecular mechanisms of chromatin remodelers-mediated plant drought responses remain obscure. In this study, we found a novel interactor of BRM called BRM-associated protein involved in drought response (BAPID), which interacted with SWI/SNF chromatin remodeler BRM and drought-induced transcription factor Di19. Our findings demonstrated that BAPID acted as a positive drought regulator since drought tolerance was increased in BAPID-overexpressing plants, but decreased in BAPID-deficient plants, and physically bound to PR1, PR2, and PR5 promoters to mediate expression of PR genes to defend against dehydration stress. Genetic approaches demonstrated that BRM acted epistatically to BAPID and Di19 in drought response in Arabidopsis. Furthermore, the BAPID protein-inhibited interaction between BRM and Di19, and suppressed the inhibition of BRM on the Di19-PR module by mediating the H3K27me3 deposition at PR loci, thus changing nucleosome accessibility of Di19 and activating transcription of PR genes in response to drought. Our results shed light on the molecular mechanism whereby the BAPID-BRM-Di19-PRs pathway mediates plant drought responses. We provide data improving our understanding of chromatin remodeler-mediated plant drought regulation network.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Secas , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Estresse Fisiológico , Montagem e Desmontagem da Cromatina , Regiões Promotoras Genéticas/genética , Plantas Geneticamente Modificadas , Adenosina Trifosfatases
5.
BMC Genomics ; 25(1): 492, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760719

RESUMO

Rapeseed (Brassica napus L.), accounts for nearly 16% of vegetable oil, is the world's second produced oilseed. However, pod shattering has caused significant yield loses in rapeseed production, particularly during mechanical harvesting. The GH28 genes can promote pod shattering by changing the structure of the pod cell wall in Arabidopsis. However, the role of the GH28 gene family in rapeseed was largely unknown. Therefore, a genome-wide comprehensive analysis was conducted to classify the role of GH28 gene family on rapeseed pod shattering. A total of 37 BnaGH28 genes in the rapeseed genome were identified. These BnaGH28s can be divided into five groups (Group A-E), based on phylogenetic and synteny analysis. Protein property, gene structure, conserved motif, cis-acting element, and gene expression profile of BnaGH28 genes in the same group were similar. Specially, the expression level of genes in group A-D was gradually decreased, but increased in group E with the development of silique. Among eleven higher expressed genes in group E, two BnaGH28 genes (BnaA07T0199500ZS and BnaC06T0206500ZS) were significantly regulated by IAA or GA treatment. And the significant effects of BnaA07T0199500ZS variation on pod shattering resistance were also demonstrated in present study. These results could open a new window for insight into the role of BnaGH28 genes on pod shattering resistance in rapeseed.


Assuntos
Brassica napus , Filogenia , Proteínas de Plantas , Brassica napus/genética , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Família Multigênica , Genoma de Planta , Sintenia , Perfilação da Expressão Gênica
6.
Pharmacogenet Genomics ; 34(2): 33-42, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37906625

RESUMO

BACKGROUND: Many factors affect the survival rate after kidney transplantation, including laboratory tests, medicine therapy and pharmacogenomics. Tacrolimus, mycophenolate mofetil and methylprednisolone were used as an immunosuppressive regimen after kidney transplantation. The primary goal of this study was to investigate the factors affecting the tacrolimus concentrations and mycophenolate mofetil area under the curve of mycophenolic acid AUC-MPA. Secondary goals were to study the association between perioperative period laboratory tests, medicine therapy, CYP3A5 genetic polymorphisms, and survival rate in kidney renal transplant patients. METHODS: A total of 303 patients aged above 18 years were enrolled in this study. Their clinical characteristics, laboratory tests, and medicine therapy regimens were collected. We followed the patients for survival for 1 year after kidney transplantation. RESULTS: Multivariable logistic analyses reveal that age greater than 50 years, and the CY3A5 *3*3 genotype were independently, positively, and significantly related to tacrolimus C/D ratio at 7 days. At 1 month of follow-up, only CYP3A5 *3*3 was associated with tacrolimus C/D ratio. Basiliximab, Imipenem and cilastatin sodium, sex were associated with mycophenolate mofetil AUC-MPA at 7 days. In the COX regression analysis, a high-density lipoprotein cholesterol level≥1 mmol/L was identified as a positive independent risk factors for the survival rate, while a creatinine level ≥200 µmol/L was a negatively independent risk factors for survival rate. CONCLUSION: These results suggest that age, genes, and drug-drug interaction can affect the concentration of tacrolimus.


Assuntos
Transplante de Rim , Humanos , Idoso , Pessoa de Meia-Idade , Transplante de Rim/efeitos adversos , Tacrolimo/uso terapêutico , Ácido Micofenólico/uso terapêutico , Citocromo P-450 CYP3A , Creatinina , Taxa de Sobrevida , Imunossupressores/efeitos adversos , Quimioterapia Combinada , Rejeição de Enxerto
7.
BMC Plant Biol ; 24(1): 21, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166550

RESUMO

Rapeseed (Brassica napus L.) with short or no dormancy period are easy to germinate before harvest (pre-harvest sprouting, PHS). PHS has seriously decreased seed weight and oil content in B. napus. Short-chain dehydrogenase/ reductase (SDR) genes have been found to related to seed dormancy by promoting ABA biosynthesis in rice and Arabidopsis. In order to clarify whether SDR genes are the key factor of seed dormancy in B. napus, homology sequence blast, protein physicochemical properties, conserved motif, gene structure, cis-acting element, gene expression and variation analysis were conducted in present study. Results shown that 142 BnaSDR genes, unevenly distributed on 19 chromosomes, have been identified in B. napus genome. Among them, four BnaSDR gene clusters present in chromosome A04、A05、C03、C04 were also identified. These 142 BnaSDR genes were divided into four subfamilies on phylogenetic tree. Members of the same subgroup have similar protein characters, conserved motifs, gene structure, cis-acting elements and tissue expression profiles. Specially, the expression levels of genes in subgroup A, B and C were gradually decreased, but increased in subgroup D with the development of seeds. Among seven higher expressed genes in group D, six BnaSDR genes were significantly higher expressed in weak dormancy line than that in nondormancy line. And the significant effects of BnaC01T0313900ZS and BnaC03T0300500ZS variation on seed dormancy were also demonstrated in present study. These findings provide a key information for investigating the function of BnaSDRs on seed dormancy in B. napus.


Assuntos
Brassica napus , Brassica rapa , Brassica napus/genética , Brassica napus/metabolismo , Dormência de Plantas/genética , Perfilação da Expressão Gênica , Filogenia , Brassica rapa/genética , Sementes/genética , Sementes/metabolismo , Regulação da Expressão Gênica de Plantas
8.
BMC Med ; 22(1): 269, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926749

RESUMO

BACKGROUND: In the USA, the prolonged effective survival of cancer population has brought significant attention to the rising risk of cardiometabolic morbidity and mortality in this population. This heightened risk underscores the urgent need for research into effective pharmacological interventions for cancer survivors. Notably, metformin, a well-known metabolic regulator with pleiotropic effects, has shown protective effects against cardiometabolic disorders in diabetic individuals. Despite these promising indications, evidence supporting its efficacy in improving cardiometabolic outcomes in cancer survivors remains scarce. METHODS: A prospective cohort was established using a nationally representative sample of cancer survivors enrolled in the US National Health and Nutrition Examination Survey (NHANES), spanning 2003 to 2018. Outcomes were derived from patient interviews, physical examinations, and public-access linked mortality archives up to 2019. The Oxidative Balance Score was utilized to assess participants' levels of oxidative stress. To evaluate the correlations between metformin use and the risk of cardiometabolic diseases and related mortality, survival analysis of cardiometabolic mortality was performed by Cox proportional hazards model, and cross-sectional analysis of cardiometabolic diseases outcomes was performed using logistic regression models. Interaction analyses were conducted to explore the specific pharmacological mechanism of metformin. RESULTS: Among 3995 cancer survivors (weighted population, 21,671,061, weighted mean [SE] age, 62.62 [0.33] years; 2119 [53.04%] females; 2727 [68.26%] Non-Hispanic White individuals), 448 reported metformin usage. During the follow-up period of up to 17 years (median, 6.42 years), there were 1233 recorded deaths, including 481 deaths from cardiometabolic causes. Multivariable models indicated that metformin use was associated with a lower risk of all-cause (hazard ratio [HR], 0.62; 95% confidence interval [CI], 0.47-0.81) and cardiometabolic (HR, 0.65; 95% CI, 0.44-0.97) mortality compared with metformin nonusers. Metformin use was also correlated with a lower risk of total cardiovascular disease (odds ratio [OR], 0.41; 95% CI, 0.28-0.59), stroke (OR, 0.44; 95% CI, 0.26-0.74), hypertension (OR, 0.27; 95% CI, 0.14-0.52), and coronary heart disease (OR, 0.41; 95% CI, 0.21-0.78). The observed inverse associations were consistent across subgroup analyses in four specific cancer populations identified as cardiometabolic high-risk groups. Interaction analyses suggested that metformin use as compared to non-use may counter-balance oxidative stress. CONCLUSIONS: In this cohort study involving a nationally representative population of US cancer survivors, metformin use was significantly correlated with a lower risk of cardiometabolic diseases, all-cause mortality, and cardiometabolic mortality.


Assuntos
Sobreviventes de Câncer , Doenças Cardiovasculares , Metformina , Humanos , Metformina/uso terapêutico , Feminino , Masculino , Sobreviventes de Câncer/estatística & dados numéricos , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Doenças Cardiovasculares/mortalidade , Estudos Prospectivos , Hipoglicemiantes/uso terapêutico , Idoso , Estudos Transversais , Inquéritos Nutricionais , Estudos de Coortes , Neoplasias/mortalidade
9.
J Intern Med ; 295(4): 557-568, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38111091

RESUMO

BACKGROUND: Effects of intensive blood pressure (BP) control on cognitive outcomes in patients with excess orthostatic BP changes are unclear. We aimed to evaluate whether orthostatic BP changes modified the effects of BP intervention on cognitive impairment. METHODS: We analyzed 8547 participants from the Systolic Blood Pressure Intervention Trial Memory and cognition IN Decreased Hypertension. Associations between orthostatic BP changes and incident cognitive outcomes were evaluated by restricted cubic spline curves based on Cox models. The interactions between orthostatic BP changes and intensive BP intervention were assessed. RESULTS: The U-shaped associations were observed between baseline orthostatic systolic BP changes and cognitive outcomes. However, there were insignificant interactions between either change in orthostatic systolic BP (P for interaction = 0.81) or diastolic BP (P for interaction = 0.32) and intensive BP intervention for the composite outcome of probable dementia or mild cognitive impairment (MCI). The hazard ratio of intensive versus standard target for the composite cognitive outcome was 0.82 (95% CI 0.50-1.35) in those with an orthostatic systolic BP reduction of >20 mmHg and 0.41 (95% CI 0.21-0.80) in those with an orthostatic systolic BP increase of >20 mmHg. Results were similar for probable dementia and MCI. The annual changes in global cerebral blood flow (P for interaction = 0.86) consistently favored intensive BP treatment across orthostatic systolic BP changes. CONCLUSION: Intensive BP control did not have a deteriorating effect on cognitive outcomes among hypertensive patients experiencing significant postural BP changes.


Assuntos
Disfunção Cognitiva , Demência , Hipertensão , Hipotensão Ortostática , Humanos , Pressão Sanguínea , Cognição , Hipertensão/tratamento farmacológico , Hipotensão Ortostática/psicologia
10.
Small ; 20(28): e2400644, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38326079

RESUMO

Tissue development is mediated by a combination of mechanical and biological signals. Currently, there are many reports on biological signals regulating repair. However, insufficient attention is paid to the process of mechanical regulation, especially the active mechanical regulation in vivo, which has not been realized. Herein, a novel dynamically regulated repair system for both in vitro and in vivo applications is developed, which utilizes magnetic nanoparticles as non-contact actuators to activate hydrogels. The magnetic hydrogel can be periodically activated and deformed to different amplitudes by a dynamic magnetic system. An in vitro skin model is used to explore the impact of different dynamic stimuli on cellular mechano-transduction signal activation and cell differentiation. Specifically, the effect of mechanical stimulation on the phenotypic transition of fibroblasts to myofibroblasts is investigated. Furthermore, in vivo results verify that dynamic massage can simulate and enhance the traction effect in skin defects, thereby accelerating the wound healing process by promoting re-epithelialization and mediating dermal contraction.


Assuntos
Bandagens , Massagem , Cicatrização , Animais , Massagem/métodos , Fibroblastos , Humanos , Hidrogéis/química , Diferenciação Celular , Pele , Camundongos , Miofibroblastos/citologia
11.
Small ; 20(31): e2400698, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38446055

RESUMO

Triboelectric nanogenerator (TENG) is a promising solution to harvest the low-frequency, low-actuation-force, and high-entropy droplet energy. Conventional attempts mainly focus on maximizing electrostatic energy harvest on the liquid-solid surface, but enormous kinetic energy of droplet hitting the substrate is directly dissipated, limiting the output performance. Here, a dual-mode TENG (DM-TENG) is proposed to efficiently harvest both electrostatic energy at liquid-solid surface from a droplet TENG (D-TENG) and elastic potential energy of the vibrated cantilever from a contact-separation TENG (CS-TENG). Triggered by small droplets, the flexible cantilever beam, rather than conventional stiff ones, can easily vibrate multiple times with large amplitude, enabling frequency multiplication of CS-TENG and producing amplified output charges. Combining with the top electrode design to sufficiently utilize charges at liquid-solid interface, a record-high output charge of 158 nC is realized by single droplet. The energy conversion efficiency of DM-TENG is 2.66-fold of D-TENG. An array system with the specially designed power management circuit is also demonstrated for building self-powered system, offering promising applications for efficiently harvesting raindrop energy.

12.
Blood ; 139(4): 502-522, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34610101

RESUMO

Proton export is often considered a detoxifying process in animal cells, with monocarboxylate symporters coexporting excessive lactate and protons during glycolysis or the Warburg effect. We report a novel mechanism by which lactate/H+ export is sufficient to induce cell growth. Increased intracellular pH selectively activates catalysis by key metabolic gatekeeper enzymes HK1/PKM2/G6PDH, thereby enhancing glycolytic and pentose phosphate pathway carbon flux. The result is increased nucleotide levels, NADPH/NADP+ ratio, and cell proliferation. Simply increasing the lactate/proton symporter monocarboxylate transporter 4 (MCT4) or the sodium-proton antiporter NHE1 was sufficient to increase intracellular pH and give normal hematopoietic cells a significant competitive growth advantage in vivo. This process does not require additional cytokine triggers and is exploited in malignancy, where leukemogenic mutations epigenetically increase MCT4. Inhibiting MCT4 decreased intracellular pH and carbon flux and eliminated acute myeloid leukemia-initiating cells in mice without cytotoxic chemotherapy. Intracellular alkalization is a primitive mechanism by which proton partitioning can directly reprogram carbon metabolism for cell growth.


Assuntos
Carbono/metabolismo , Proliferação de Células , Ácido Láctico/metabolismo , Leucemia Mieloide Aguda/metabolismo , Animais , Transformação Celular Neoplásica/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos C57BL , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/metabolismo , Via de Pentose Fosfato , Prótons , Células Tumorais Cultivadas
13.
Theor Appl Genet ; 137(2): 33, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38285195

RESUMO

KEY MESSAGE: Three major QTLs qA01, qB04.1 and qB05 for VLCFA content and their corresponding allele-specific markers will benefit peanut low VLCFA breeding, and a candidate gene Arahy.IF1JV3 was predicted. Peanut is a globally significant oilseed crop worldwide, and contains a high content (20%) of saturated fatty acid (SFA) in its seeds. As high level SFA intake in human dietary may increase the cardiovascular disease risk, reducing the SFA content in peanut is crucial for improving its nutritional quality. Half of the SFAs in peanut are very long-chain fatty acids (VLCFA), so reducing the VLCFA content is a feasible strategy to decrease the total SFA content. Luoaowan with extremely low VLCFA (4.80%) was crossed with Jihua16 (8.00%) to construct an F2:4 population. Three major QTLs including qA01, qB04.1 and qB05 for VLCFA content were detected with 4.43 ~ 14.32% phenotypic variation explained through linkage mapping. Meanwhile, three genomic regions on chromosomes B03, B04 and B05 were identified via BSA-seq approach. Two co-localized intervals on chromosomes B04 (100.10 ~ 103.97 Mb) and B05 (6.39 ~ 10.90 Mb) were identified. With markers developed based on SNP/InDel variations in qA01 between the two parents, the remaining interval was refined to 103.58 ~ 111.14 Mb. A candidate gene Arahy.IF1JV3 encoding a ß-ketoacyl-CoA synthase was found in qA01, and its expression level in Luoaowan was significantly lower than that in Jihua16. Allele-specific markers targeting qA01, qB04.1 and qB05 were developed and validated in F4 population, and an elite line with high oleic, low VLCFA (5.05%) and low SFA (11.48%) contents was selected. This study initially revealed the genetic mechanism of VLCFA content, built a marker-assisted selection system for low VLCFA breeding, and provided an effective method to decrease the SFA content in peanut.


Assuntos
Arachis , Melhoramento Vegetal , Humanos , Arachis/genética , Mapeamento Cromossômico , Locos de Características Quantitativas , Ácidos Graxos
14.
Pharmacol Res ; 201: 107105, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38367917

RESUMO

Chronic interstitial fibrosis presents a significant challenge to the long-term survival of transplanted kidneys. Our research has shown that reduced expression of acyl-coenzyme A oxidase 1 (ACOX1), which is the rate-limiting enzyme in the peroxisomal fatty acid ß-oxidation pathway, contributes to the development of fibrosis in renal allografts. ACOX1 deficiency leads to lipid accumulation and excessive oxidation of polyunsaturated fatty acids (PUFAs), which mediate epithelial-mesenchymal transition (EMT) and extracellular matrix (ECM) reorganization respectively, thus causing fibrosis in renal allografts. Furthermore, activation of Toll-like receptor 4 (TLR4)-nuclear factor kappa-B (NF-κB) signaling induced ACOX1 downregulation in a DNA methyltransferase 1 (DNMT1)-dependent manner. Overconsumption of PUFA resulted in endoplasmic reticulum (ER) stress, which played a vital role in facilitating ECM reorganization. Supplementation with PUFAs contributed to delayed fibrosis in a rat model of renal transplantation. The study provides a novel therapeutic approach that can delay chronic interstitial fibrosis in renal allografts by targeting the disorder of lipid metabolism.


Assuntos
Acil-CoA Oxidase , Transplante de Rim , Rim , Doenças Metabólicas , Animais , Ratos , Acil-CoA Oxidase/metabolismo , Aloenxertos , Fibrose , Rim/patologia , Lipídeos
15.
Microb Cell Fact ; 23(1): 151, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789996

RESUMO

BACKGROUND: Xylans are polysaccharides that are naturally abundant in agricultural by-products, such as cereal brans and straws. Microbial degradation of arabinoxylan is facilitated by extracellular esterases that remove acetyl, feruloyl, and p-coumaroyl decorations. The bacterium Ruminiclostridium cellulolyticum possesses the Xua (xylan utilization associated) system, which is responsible for importing and intracellularly degrading arabinoxylodextrins. This system includes an arabinoxylodextrins importer, four intracellular glycosyl hydrolases, and two intracellular esterases, XuaH and XuaJ which are encoded at the end of the gene cluster. RESULTS: Genetic studies demonstrate that the genes xuaH and xuaJ are part of the xua operon, which covers xuaABCDD'EFGHIJ. This operon forms a functional unit regulated by the two-component system XuaSR. The esterases encoded at the end of the cluster have been further characterized: XuaJ is an acetyl esterase active on model substrates, while XuaH is a xylan feruloyl- and p-coumaryl-esterase. This latter is active on oligosaccharides derived from wheat bran and wheat straw. Modelling studies indicate that XuaH has the potential to interact with arabinoxylobiose acylated with mono- or diferulate. The intracellular esterases XuaH and XuaJ are believed to allow the cell to fully utilize the complex acylated arabinoxylo-dextrins imported into the cytoplasm during growth on wheat bran or straw. CONCLUSIONS: This study reports for the first time that a cytosolic feruloyl esterase is part of an intracellular arabinoxylo-dextrin import and degradation system, completing its cytosolic enzymatic arsenal. This system represents a new pathway for processing highly-decorated arabinoxylo-dextrins, which could provide a competitive advantage to the cell and may have interesting biotechnological applications.


Assuntos
Lignina , Xilanos , Xilanos/metabolismo , Lignina/metabolismo , Biomassa , Ácidos Cumáricos/metabolismo , Oligossacarídeos/metabolismo , Clostridiales/metabolismo , Óperon , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Família Multigênica , Acetilesterase/metabolismo , Acetilesterase/genética , Hidrolases de Éster Carboxílico
16.
Europace ; 26(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38587311

RESUMO

AIMS: Pericardiocentesis is usually completed under fluoroscopy. The electroanatomic mapping (EAM) system allows visualizing puncture needle tip (NT) while displaying the electrogram recorded from NT, making it possible to obtain epicardial access (EA) independent of fluoroscopy. This study was designed to establish and validate a technique by which EA is obtained under guidance of three-dimensional (3D) EAM combined with NT electrogram. METHODS AND RESULTS: 3D shell of the heart was generated, and the NT was made trackable in the EAM system. Unipolar NT electrogram was continuously monitored. Penetration into pericardial sac was determined by an increase in NT potential amplitude and an injury current. A long guidewire of which the tip was also visible in the EAM system was advanced to confirm EA. Epicardial access was successfully obtained without complication in 13 pigs and 22 patients. In the animals, NT potential amplitude was 3.2 ± 1.0 mV when it was located in mediastinum, 5.2 ± 1.6 mV when in contact with fibrous pericardium, and 9.8 ± 2.8 mV after penetrating into pericardial sac (all P ≤ 0.001). In human subjects, it measured 1.54 ± 0.40 mV, 3.61 ± 1.08 mV, and 7.15 ± 2.88 mV, respectively (all P < 0.001). Fluoroscopy time decreased in every 4-5 cases (64 ± 15, 23 ± 17, and 0 s for animals 1-4, 5-8, 9-13, respectively, P = 0.01; 44 ± 23, 31 ± 18, 4±7 s for patients 1-7, 8-14, 15-22, respectively, P < 0.001). In five pigs and seven patients, EA was obtained without X-ray exposure. CONCLUSION: By tracking NT in the 3D EAM system and continuously monitoring the NT electrogram, it is feasible and safe to obtain EA with minimum or no fluoroscopic guidance.


Assuntos
Técnicas Eletrofisiológicas Cardíacas , Mapeamento Epicárdico , Imageamento Tridimensional , Agulhas , Pericárdio , Humanos , Masculino , Feminino , Animais , Pericárdio/diagnóstico por imagem , Pericárdio/cirurgia , Pessoa de Meia-Idade , Imageamento Tridimensional/métodos , Idoso , Técnicas Eletrofisiológicas Cardíacas/instrumentação , Técnicas Eletrofisiológicas Cardíacas/métodos , Mapeamento Epicárdico/métodos , Pericardiocentese/métodos , Punções , Valor Preditivo dos Testes , Adulto , Suínos , Modelos Animais , Potenciais de Ação , Sus scrofa , Fluoroscopia
17.
BMC Cardiovasc Disord ; 24(1): 398, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085776

RESUMO

BACKGROUND: Stroke and thromboembolism in nonvalvular atrial fibrillation (NVAF) primarily arise from thrombi or sludge in the left atrial appendage (LAA). Comprehensive insight into the characteristics of these formations is essential for effective risk assessment and management. METHODS: We conducted a single-center retrospective observational of 176 consecutive NVAF patients with confirmed atrial/appendage thrombus or sludge determined by a pre-ablation transesophageal echocardiogram (TEE) from December 2017 to April 2019. We obtained clinical and echocardiographic characteristics, including left atrial appendage emptying velocity (LAAeV) and filling velocity (LAAfV). Data analysis focused on identifying the morphology and location of thrombus or sludge. Patients were divided into the solid thrombus and sludge groups, and the correlation between clinical and echocardiographic variables and thrombotic status was analyzed. RESULTS: Morphological classification: In total, thrombi were identified in 78 patients, including 71 (40.3%) mass and 7 (4.0%) lamellar, while sludge was noted in 98 (55.7%). Location classification: 92.3% (72/78) of patients had thrombus confined to the LAA; 3.8% (3/78) had both LA and LAA involvement; 2.7% (2/78) had LA, LAA and RAA extended into the RA, the remained 1.2%(1/78) was isolated to RAA. 98.0% (96/98) of patients had sludge confined to the LAA; the remaining 2.0% (2/98) were present in the atrial septal aneurysm, which protrusion of interatrial septum into the RA. The thrombus and sludge groups showed low LAAeV (19.43 ± 9.59 cm/s) or LAAfV (17.40 ± 10.09 cm/s). Only LA dimension ≥ 40 mm was independently associated with the thrombus state in the multivariable model. CONCLUSION: This cohort study identified rare thrombus morphology and systematically summarized the classification of thrombus morphology. The distribution of thrombus and sludge outside limited to LAA was updated, including bilateral atrial and appendage involvement and rare atrial septal aneurysm sludge. LAAeV and LAAfV were of limited value in distinguishing solid thrombus from sludge. CLINICAL TRIAL NUMBER: ChiCTR-OCH-13,003,729.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Ecocardiografia Transesofagiana , Trombose , Humanos , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/diagnóstico , Estudos Retrospectivos , Masculino , Feminino , Trombose/diagnóstico por imagem , Trombose/etiologia , Idoso , Pessoa de Meia-Idade , Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/fisiopatologia , Fatores de Risco , Valor Preditivo dos Testes , Função do Átrio Esquerdo , Cardiopatias/diagnóstico por imagem , Cardiopatias/fisiopatologia , Tromboembolia/etiologia , Tromboembolia/diagnóstico por imagem , Tromboembolia/diagnóstico
18.
Pacing Clin Electrophysiol ; 47(4): 511-517, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38407298

RESUMO

BACKGROUND: Wearable devices based on the PPG algorithm can detect atrial fibrillation (AF) effectively. However, further investigation of its application on long-term, continuous monitoring of AF burden is warranted. METHOD: The performance of a smartwatch with continuous photoplethysmography (PPG) and PPG-based algorithms for AF burden estimation was evaluated in a prospective study enrolling AF patients admitted to Beijing Anzhen Hospital for catheter ablation from September to November 2022. A continuous Electrocardiograph patch (ECG) was used as the reference device to validate algorithm performance for AF detection in 30-s intervals. RESULTS: A total of 578669 non-overlapping 30-s intervals for PPG and ECG each from 245 eligible patients were generated. An interval-level sensitivity of PPG was 96.3% (95% CI 96.2%-96.4%), and specificity was 99.5% (95% CI 99.5%-99.6%) for the estimation of AF burden. AF burden estimation by PPG was highly correlated with AF burden calculated by ECG via Pearson correlation coefficient (R2 = 0.996) with a mean difference of -0.59 (95% limits of agreement, -7.9% to 6.7%). The subgroup study showed the robust performance of the algorithm in different subgroups, including heart rate and different hours of the day. CONCLUSION: Our results showed the smartwatch with an algorithm-based PPG monitor has good accuracy and stability in continuously monitoring AF burden compared with ECG patch monitors, indicating its potential for diagnosing and managing AF.


Assuntos
Fibrilação Atrial , Humanos , Fibrilação Atrial/diagnóstico , Fotopletismografia/métodos , Estudos Prospectivos , Sensibilidade e Especificidade , Algoritmos , Eletrocardiografia/métodos
19.
Pacing Clin Electrophysiol ; 47(4): 518-524, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38407374

RESUMO

BACKGROUND: Left bundle branch block (LBBB) and atrial fibrillation (AF) are commonly coexisting conditions. The impact of LBBB on catheter ablation of AF has not been well determined. This study aims to explore the long-term outcomes of patients with AF and LBBB after catheter ablation. METHODS: Forty-two patients with LBBB of 11,752 patients who underwent catheter ablation of AF from 2011 to 2020 were enrolled as LBBB group. After propensity score matching in a 1:4 ratio, 168 AF patients without LBBB were enrolled as non-LBBB group. Late recurrence and a composite endpoint of stroke, all-cause mortality, and cardiovascular hospitalization were compared between the two groups. RESULTS: Late recurrence rate was significantly higher in the LBBB group than that in the non-LBBB group (54.8% vs. 31.5%, p = .034). Multivariate analysis showed that LBBB was an independent risk factor for late recurrence after catheter ablation of AF (hazard ratio [HR] 2.19, 95% confidence interval [CI] 1.09-4.40, p = .031). LBBB group was also associated with a significantly higher incidence of the composite endpoint (21.4% vs. 6.5%, HR 3.98, 95% CI 1.64-9.64, p = .002). CONCLUSIONS: LBBB was associated with a higher risk for late recurrence and a higher incidence of composite endpoint in the patients underwent catheter ablation.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Acidente Vascular Cerebral , Humanos , Bloqueio de Ramo/etiologia , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Ablação por Cateter/efeitos adversos , Resultado do Tratamento , Recidiva
20.
Bioorg Chem ; 153: 107785, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39255609

RESUMO

Invasive fungal infections have high morbidity and mortality rates and have become one of the most serious threats to human health. In the present study, a series of triazole antifungal derivatives with phenylthiophene backbone were obtained by structural modification of the lead compound using Iodiconazole as the lead compound. Among them, compound 19g is a triazole antifungal compound with 4-chloro-2-fluoro phenylthiophene backbone, which showed optimal antifungal activity against Candida albicans, Cryptococcus neoformans, and Aspergillus, with a MIC80 value of 0.0625 µg/mL. In addition, compounds 19e, 19f, 19g, 19h, 19i and 19k exhibited different levels of inhibitory activity against fluconazole-resistant strains with MIC80 values ranging from 0.0625 µg/mL to 32 µg/mL. Since compound 19g had optimal in vitro antifungal activity, we selected 19g for human liver microsomal stability and CYP enzyme inhibition assays as well as further evaluated the inhibitory activity of compound 19g on normal and cancerous cells in humans. Finally, we verified the inhibitory effect of compound 19g on the filamentation of Candida albicans and determined the mechanism of action by sterol composition analysis.

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