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1.
Proc Natl Acad Sci U S A ; 121(25): e2321614121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38857401

RESUMO

The medial prefrontal cortex (mPFC) is a key brain structure for higher cognitive functions such as decision-making and goal-directed behavior, many of which require awareness of spatial variables including one's current position within the surrounding environment. Although previous studies have reported spatially tuned activities in mPFC during memory-related trajectory, the spatial tuning of mPFC network during freely foraging behavior remains elusive. Here, we reveal geometric border or border-proximal representations from the neural activity of mPFC ensembles during naturally exploring behavior, with both allocentric and egocentric boundary responses. Unlike most of classical border cells in the medial entorhinal cortex (MEC) discharging along a single wall, a large majority of border cells in mPFC fire particularly along four walls. mPFC border cells generate new firing fields to external insert, and remain stable under darkness, across distinct shapes, and in novel environments. In contrast to hippocampal theta entrainment during spatial working memory tasks, mPFC border cells rarely exhibited theta rhythmicity during spontaneous locomotion behavior. These findings reveal spatially modulated activity in mPFC, supporting local computation for cognitive functions involving spatial context and contributing to a broad spatial tuning property of cortical circuits.


Assuntos
Córtex Pré-Frontal , Ritmo Teta , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/citologia , Animais , Ritmo Teta/fisiologia , Masculino , Camundongos , Córtex Entorrinal/fisiologia , Neurônios/fisiologia , Hipocampo/fisiologia , Memória Espacial/fisiologia , Camundongos Endogâmicos C57BL , Memória de Curto Prazo/fisiologia
2.
Nucleic Acids Res ; 52(6): 2808-2820, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38426933

RESUMO

Chemical modifications in RNAs play crucial roles in diversifying their structures and regulating numerous biochemical processes. Since the 1990s, several hydrophobic prenyl-modifications have been discovered in various RNAs. Prenyl groups serve as precursors for terpenes and many other biological molecules. The processes of prenylation in different macromolecules have been extensively studied. We introduce here a novel chemical biology toolkit that not only labels i6A, a prenyl-modified RNA residue, by leveraging the unique reactivity of the prenyl group, but also provides a general strategy to incorporate fluorescence functionalities into RNAs for molecular tracking purposes. Our findings revealed that iodine-mediated cyclization reactions of the prenyl group occur rapidly, transforming i6A from a hydrogen-bond acceptor to a donor. Based on this reactivity, we developed an Iodine-Mediated Cyclization and Reverse Transcription (IMCRT) tRNA-seq method, which can profile all nine endogenous tRNAs containing i6A residues in Saccharomyces cerevisiae with single-base resolution. Furthermore, under stress conditions, we observed a decline in i6A levels in budding yeast, accompanied by significant decrease of mutation rate at A37 position. Thus, the IMCRT tRNA-seq method not only permits semi-quantification of i6A levels in tRNAs but also holds potential for transcriptome-wide detection and analysis of various RNA species containing i6A modifications.


Assuntos
Isopenteniladenosina , Processamento Pós-Transcricional do RNA , RNA de Transferência , Iodo , Neopreno , RNA de Transferência/metabolismo , Saccharomyces cerevisiae , Análise de Sequência de RNA
3.
Brain ; 147(4): 1436-1456, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37951597

RESUMO

The acyl-CoA-binding domain-containing protein 6 (ACBD6) is ubiquitously expressed, plays a role in the acylation of lipids and proteins and regulates the N-myristoylation of proteins via N-myristoyltransferase enzymes (NMTs). However, its precise function in cells is still unclear, as is the consequence of ACBD6 defects on human pathophysiology. Using exome sequencing and extensive international data sharing efforts, we identified 45 affected individuals from 28 unrelated families (consanguinity 93%) with bi-allelic pathogenic, predominantly loss-of-function (18/20) variants in ACBD6. We generated zebrafish and Xenopus tropicalis acbd6 knockouts by CRISPR/Cas9 and characterized the role of ACBD6 on protein N-myristoylation with myristic acid alkyne (YnMyr) chemical proteomics in the model organisms and human cells, with the latter also being subjected further to ACBD6 peroxisomal localization studies. The affected individuals (23 males and 22 females), aged 1-50 years, typically present with a complex and progressive disease involving moderate-to-severe global developmental delay/intellectual disability (100%) with significant expressive language impairment (98%), movement disorders (97%), facial dysmorphism (95%) and mild cerebellar ataxia (85%) associated with gait impairment (94%), limb spasticity/hypertonia (76%), oculomotor (71%) and behavioural abnormalities (65%), overweight (59%), microcephaly (39%) and epilepsy (33%). The most conspicuous and common movement disorder was dystonia (94%), frequently leading to early-onset progressive postural deformities (97%), limb dystonia (55%) and cervical dystonia (31%). A jerky tremor in the upper limbs (63%), a mild head tremor (59%), parkinsonism/hypokinesia developing with advancing age (32%) and simple motor and vocal tics were among other frequent movement disorders. Midline brain malformations including corpus callosum abnormalities (70%), hypoplasia/agenesis of the anterior commissure (66%), short midbrain and small inferior cerebellar vermis (38% each) as well as hypertrophy of the clava (24%) were common neuroimaging findings. Acbd6-deficient zebrafish and Xenopus models effectively recapitulated many clinical phenotypes reported in patients including movement disorders, progressive neuromotor impairment, seizures, microcephaly, craniofacial dysmorphism and midbrain defects accompanied by developmental delay with increased mortality over time. Unlike ACBD5, ACBD6 did not show a peroxisomal localization and ACBD6-deficiency was not associated with altered peroxisomal parameters in patient fibroblasts. Significant differences in YnMyr-labelling were observed for 68 co- and 18 post-translationally N-myristoylated proteins in patient-derived fibroblasts. N-myristoylation was similarly affected in acbd6-deficient zebrafish and X. tropicalis models, including Fus, Marcks and Chchd-related proteins implicated in neurological diseases. The present study provides evidence that bi-allelic pathogenic variants in ACBD6 lead to a distinct neurodevelopmental syndrome accompanied by complex and progressive cognitive and movement disorders.


Assuntos
Deficiência Intelectual , Microcefalia , Transtornos dos Movimentos , Malformações do Sistema Nervoso , Transtornos do Neurodesenvolvimento , Animais , Feminino , Humanos , Masculino , Transportadores de Cassetes de Ligação de ATP , Deficiência Intelectual/genética , Transtornos dos Movimentos/genética , Malformações do Sistema Nervoso/genética , Transtornos do Neurodesenvolvimento/genética , Tremor , Peixe-Zebra , Lactente , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade
4.
Nucleic Acids Res ; 51(8): 4055-4063, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36477864

RESUMO

The ability to create stimuli-responsive DNA nanostructures has played a prominent role in dynamic DNA nanotechnology. Primary among these is the process of toehold-based strand displacement, where a nucleic acid molecule can act as a trigger to cause conformational changes in custom-designed DNA nanostructures. Here, we add another layer of control to strand displacement reactions through a 'toehold clipping' process. By designing DNA complexes with a photocleavable linker-containing toehold or an RNA toehold, we show that we can use light (UV) or enzyme (ribonuclease) to eliminate the toehold, thus preventing strand displacement reactions. We use molecular dynamics simulations to analyze the structural effects of incorporating a photocleavable linker in DNA complexes. Beyond simple DNA duplexes, we also demonstrate the toehold clipping process in a model DNA nanostructure, by designing a toehold containing double-bundle DNA tetrahedron that disassembles when an invading strand is added, but stays intact after the toehold clipping process even in the presence of the invading strand. This work is an example of combining multiple physical or molecular stimuli to provide additional remote control over DNA nanostructure reconfiguration, advances that hold potential use in biosensing, drug delivery or molecular computation.


Assuntos
DNA , Nanoestruturas , DNA/química , Nanotecnologia , RNA , Simulação de Dinâmica Molecular
5.
Nucleic Acids Res ; 51(20): 11291-11297, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37811879

RESUMO

There are >170 naturally occurring RNA chemical modifications, with both known and unknown biological functions. Analytical methods for detecting chemical modifications and for analyzing their effects are relatively limited and have had difficulty keeping pace with the demand for RNA chemical biology and biochemistry research. Some modifications can affect the ability of RNA to hybridize with its complementary sequence or change the selectivity of base pairing. Here, we investigate the use of affinity-based DNA nanoswitches to resolve energetic differences in hybridization. We found that a single m3C modification can sufficiently destabilize hybridization to abolish a detection signal, while an s4U modification can selectively hybridize with G over A. These results establish proof of concept for using DNA nanoswitches to detect certain RNA modifications and analyzing their effects in base pairing stability and specificity.


Assuntos
DNA , RNA , Pareamento de Bases , Sequência de Bases , DNA/química , Hibridização de Ácido Nucleico , RNA/química
6.
Nucleic Acids Res ; 51(9): 4625-4636, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-37013991

RESUMO

Cadmium (Cd) is one of the most toxic heavy metals. Exposure to Cd can impair the functions of the kidney, respiratory system, reproductive system and skeletal system. Cd2+-binding aptamers have been extensively utilized in the development of Cd2+-detecting devices; however, the underlying mechanisms remain elusive. This study reports four Cd2+-bound DNA aptamer structures, representing the only Cd2+-specific aptamer structures available to date. In all the structures, the Cd2+-binding loop (CBL-loop) adopts a compact, double-twisted conformation and the Cd2+ ion is mainly coordinated with the G9, C12 and G16 nucleotides. Moreover, T11 and A15 within the CBL-loop form one regular Watson-Crick pair and stabilize the conformation of G9. The conformation of G16 is stabilized by the G8-C18 pair of the stem. By folding and/or stabilizing the CBL-loop, the other four nucleotides of the CBL-loop also play important roles in Cd2+ binding. Similarly to the native sequence, crystal structures, circular dichroism spectrum and isothermal titration calorimetry analysis confirm that several variants of the aptamer can recognize Cd2+. This study not only reveals the underlying basis for the binding of Cd2+ ions with the aptamer, but also extends the sequence for the construction of novel metal-DNA complex.


Assuntos
Aptâmeros de Nucleotídeos , Aptâmeros de Nucleotídeos/química , Cádmio , Conformação Molecular , DNA
7.
Small ; 20(1): e2304463, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37649191

RESUMO

The high activity of water molecules results in a series of awful parasitic reaction, which seriously impede the development of aqueous zinc batteries. Herein, a new gel electrolyte with multiple molecular anchors is designed by employing natural biomaterials from chitosan and chlorophyll derivative. The gel electrolyte firmly anchors water molecules by ternary hydrogen bonding to reduce the activity of water molecules and inhibit hydrogen evolution reaction. Meanwhile, the multipolar charged functional groups realize the gradient induction and redistribution of Zn2+ , which drives oriented Zn (002) plane deposition of Zn2+ and then achieves uniform Zn deposition and dendrite-free anode. As a result, it endows the Zn||Zn cell with over 1700 h stripping/plating processes and a high efficiency of 99.4% for the Zn||Cu cell. In addition, the Zn||V2 O5 full cells also exhibit capacity retention of 81.7% after 600 cycles at 0.5 A g-1 and excellent long-term stability over 1600 cycles at 2 A g-1 , and the flexible pouch cells can provide stable power for light-emitting diodes even after repeated bending. The gel electrolyte strategy provides a reference for reversible zinc anode and flexible wearable devices.

8.
J Biol Chem ; 298(4): 101813, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35278429

RESUMO

High plasma lipid levels have been demonstrated to increase cardiovascular disease risk. Despite advances in treatments to decrease plasma lipids, additional therapeutics are still needed because many people are intolerant or nonresponsive to these therapies. We previously showed that increasing cellular levels of microRNA-30c (miR-30c) using viral vectors or liposomes reduces plasma lipids and atherosclerosis. In this study, we aimed to synthesize potent miR-30c analogs that can be delivered to hepatoma cells without the aid of viral vectors and lipid emulsions. We hypothesized that modification of the passenger strand of miR-30c would increase the stability of miR-30c and augment its delivery to liver cells. Here, we report the successful synthesis of a series of miR-30c analogs by using different chemically modified nucleosides. In these analogs, we left the active sense strand untouched so that its biological activity remained unaltered, and we modified the passenger strand of miR-30c to enhance the stability and uptake of miR-30c by hepatoma cells through phosphorothiorate linkages and the addition of GalNAc. We show that these analogs significantly reduced apolipoprotein B secretion in Huh-7 human hepatoma cells and human primary hepatocytes without affecting apolipoprotein A1 secretion and cellular lipid levels. Our results provide a proof of concept that the passenger strand of miR-30c can be modified to increase its stability and delivery to cells while retaining the potency of the sense strand. We anticipate these miR-30c analogs will be useful in the development of more efficacious analogs for the treatment of hyperlipidemias and cardiovascular diseases.


Assuntos
Apolipoproteínas B , Carcinoma Hepatocelular , Hepatócitos , Neoplasias Hepáticas , Apolipoproteínas B/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , MicroRNAs/farmacologia
9.
Funct Integr Genomics ; 23(2): 160, 2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37178159

RESUMO

Patients diagnosed with stable coronary artery disease (CAD) are at continued risk of experiencing acute myocardial infarction (AMI). This study aims to unravel the pivotal biomarkers and dynamic immune cell changes, from an immunological, predictive, and personalized viewpoint, by implementing a machine-learning approach and a composite bioinformatics strategy. Peripheral blood mRNA data from different datasets were analyzed, and CIBERSORT was used for deconvoluting human immune cell subtype expression matrices. Weighted gene co-expression network analysis (WGCNA) in single-cell and bulk transcriptome levels was conducted to explore possible biomarkers for AMI, with a particular emphasis on examining monocytes and their involvement in cell-cell communication. Unsupervised cluster analysis was performed to categorize AMI patients into different subtypes, and machine learning methods were employed to construct a comprehensive diagnostic model to predict the occurrence of early AMI. Finally, RT-qPCR on peripheral blood samples collected from patients validated the clinical utility of the machine learning-based mRNA signature and hub biomarkers. The study identified potential biomarkers for early AMI, including CLEC2D, TCN2, and CCR1, and found that monocytes may play a vital role in AMI samples. Differential analysis revealed that CCR1 and TCN2 exhibited elevated expression levels in early AMI compared to stable CAD. Machine learning methods showed that the glmBoost+Enet [alpha=0.9] model achieved high predictive accuracy in the training set, external validation sets, and clinical samples in our hospital. The study provided comprehensive insights into potential biomarkers and immune cell populations involved in the pathogenesis of early AMI. The identified biomarkers and the constructed comprehensive diagnostic model hold great promise for predicting the occurrence of early AMI and can serve as auxiliary diagnostic or predictive biomarkers.


Assuntos
Infarto do Miocárdio , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/genética , Análise por Conglomerados , Biologia Computacional , Aprendizado de Máquina , RNA Mensageiro/genética
10.
Small ; 19(39): e2300040, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37264756

RESUMO

The programmable nature of DNA allows the construction of custom-designed static and dynamic nanostructures, and assembly conditions typically require high concentrations of magnesium ions that restricts their applications. In other solution conditions tested for DNA nanostructure assembly, only a limited set of divalent and monovalent ions are used so far (typically Mg2+ and Na+ ). Here, we investigate the assembly of DNA nanostructures in a wide variety of ions using nanostructures of different sizes: a double-crossover motif (76 bp), a three-point-star motif (~134 bp), a DNA tetrahedron (534 bp) and a DNA origami triangle (7221 bp). We show successful assembly of a majority of these structures in Ca2+ , Ba2+ , Na+ , K+ and Li+ and provide quantified assembly yields using gel electrophoresis and visual confirmation of a DNA origami triangle using atomic force microscopy. We further show that structures assembled in monovalent ions (Na+ , K+ and Li+ ) exhibit up to a 10-fold higher nuclease resistance compared to those assembled in divalent ions (Mg2+ , Ca2+ and Ba2+ ). Our work presents new assembly conditions for a wide range of DNA nanostructures with enhanced biostability.


Assuntos
Nanoestruturas , Nanotecnologia , Nanotecnologia/métodos , Conformação de Ácido Nucleico , Nanoestruturas/química , DNA/química , Cátions
11.
Genet Med ; 25(11): 100938, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37454282

RESUMO

PURPOSE: Biallelic variants in TARS2, encoding the mitochondrial threonyl-tRNA-synthetase, have been reported in a small group of individuals displaying a neurodevelopmental phenotype but with limited neuroradiological data and insufficient evidence for causality of the variants. METHODS: Exome or genome sequencing was carried out in 15 families. Clinical and neuroradiological evaluation was performed for all affected individuals, including review of 10 previously reported individuals. The pathogenicity of TARS2 variants was evaluated using in vitro assays and a zebrafish model. RESULTS: We report 18 new individuals harboring biallelic TARS2 variants. Phenotypically, these individuals show developmental delay/intellectual disability, regression, cerebellar and cerebral atrophy, basal ganglia signal alterations, hypotonia, cerebellar signs, and increased blood lactate. In vitro studies showed that variants within the TARS2301-381 region had decreased binding to Rag GTPases, likely impairing mTORC1 activity. The zebrafish model recapitulated key features of the human phenotype and unraveled dysregulation of downstream targets of mTORC1 signaling. Functional testing of the variants confirmed the pathogenicity in a zebrafish model. CONCLUSION: We define the clinico-radiological spectrum of TARS2-related mitochondrial disease, unveil the likely involvement of the mTORC1 signaling pathway as a distinct molecular mechanism, and establish a TARS2 zebrafish model as an important tool to study variant pathogenicity.


Assuntos
RNA de Transferência , Peixe-Zebra , Animais , Humanos , Mutação , Peixe-Zebra/genética , Alvo Mecanístico do Complexo 1 de Rapamicina , Ligases , Fenótipo
12.
J Org Chem ; 88(3): 1762-1771, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36691112

RESUMO

Prenyl functionalities have been widely discovered in natural products, nucleic acids, and proteins with significant biological roles in both healthy and diseased cells. In this work, we develop a series of new nitroso-based probes for the labeling, enrichment, and regulation of prenylated RAS protein, which is highly associated with ∼20% of human cancers and used to be regarded as an "undruggable" target via a sequential ene-ligation and oxime condensation (SELOC) process. We found that these nitroso species can rapidly react with prenyl-containing molecules through ene-ligation and install a molecular tag for functional applications under physiological conditions. We first investigated this ligation process on two peptide models and demonstrated its labeling efficiency on various proteins such as myoglobin, lysozyme, RNase A, BSA, and HSP40. We further coupled this reactive platform with proteolysis-targeting chimera technology targeting to increase its efficiency and accuracy, as well as to expand its application range. Using the prenylated RAS protein as the model, we demonstrated that RAS could be efficiently decorated with our nitroso probes, which further condensate with oxime and rapidly react with a pomalidomide-containing hydroxylamine probe for protein degradation. As a result, the RAS protein in both HeLa and A549 cell lines has been determined to be efficiently degraded both in vitro and in vivo. This is the first case targeting post-translational modification other than ligand-protein interaction to degrade and regulate RAS proteins. We envision that our SELOC strategy will have great potential in studying the fundamental structures and functions of prenylated biomolecules and developing new drugs based on these unique cellular pathways.


Assuntos
Neoplasias , Oximas , Humanos , Oximas/química , Proteínas ras/metabolismo , Proteínas/química , Células HeLa
13.
Arch Toxicol ; 97(11): 2983-2995, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37606655

RESUMO

Tetrabromobisphenol A-bis(2,3-dibromopropyl ether) (TBBPA-BDBPE), a commonly used brominated flame retardant as a decabromodiphenyl ether substitute, has been detected in various environmental compartments, but its health hazards remain largely unknown. Our recent study showed that low-dose exposure of male mice to TBBPA-BDBPE from postnatal day (PND) 0 to 56 caused remarkable damage to the microtubule skeleton in Sertoli cells and the blood-testis barrier (BTB) but exerted little effect on conventional reproductive endpoints in adulthood. To investigate whether TBBPA-BDBPE may cause severe reproductive impairments at late reproductive age, here, we extended exposure of historically administrated male mice to 8-month age and allowed them to mate with non-treated females for the evaluation of fertility, followed by a general examination for the reproductive system. As expected, we found that 8-month exposure to 50 µg/kg/d as well as 1000 µg/kg/d TBBPA-BDBPE caused severe damage to the reproductive system, including reduced sperm counts, increased sperm abnormality, histological alterations of testes. Moreover, microtubule damage and BTB-related impairment were still observed following 8-month exposure. Noticeably, high-dose TBBPA-BDBPE-treated mice had fewer offspring with a female-biased sex ratio. All results show that long-term exposure to TBBPA-BDBPE caused severe reproductive impairment, including poor fertility at late reproductive age. It is therefore concluded that slight testicular injuries in early life can contribute to reproductive impairment at late reproductive age, highlighting that alterations in certain non-conventional endpoints should be noticed as well as conventional endpoints in future reproductive toxicity studies.


Assuntos
Éter , Infertilidade , Masculino , Feminino , Animais , Camundongos , Sêmen , Etil-Éteres , Éteres
14.
Arch Pharm (Weinheim) ; 356(6): e2200382, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36792964

RESUMO

Influenza viruses belong to the Orthomyxoviridae family and cause acute respiratory distress in humans. The developed drug resistance toward existing drugs and the emergence of viral mutants that can escape vaccines mandate the search for novel antiviral drugs. Herein, the synthesis of epimeric 4'-methyl-4'-phosphonomethoxy [4'-C-Me-4'-C-(O-CH2 P═O)] pyrimidine ribonucleosides, their phosphonothioate [4'-C-Me-4'-C-(O-CH2 P═S)] derivatives, and their evaluation against an RNA viral panel are described. Selective formation of the α- l-lyxo epimer, [4'-C-(α)-Me-4'-C-(ß)-(O-CH2 -P(═O)(OEt)2 )] over the ß- d-ribo epimer [4'-C-(ß)-Me-4'-C-(α)-(O-CH2 -P(═O)(OEt)2 )] was explained by DFT equilibrium geometry optimizations studies. Pyrimidine nucleosides having the [4'-C-(α)-Me-4'-C-(ß)-(O-CH2 -P(═O)(OEt)2 )] framework showed specific activity against influenza A virus. Significant anti-influenza virus A (H1N1 California/07/2009 isolate) was observed with the 4'-C-(α)-Me-4'-C-(ß)-O-CH2 -P(═O)(OEt)2 -uridine derivative 1 (EC50 = 4.56 mM, SI50 > 56), 4-ethoxy-2-oxo-1(2H)-pyrimidin-1-yl derivative 3 (EC50 = 5.44 mM, SI50 > 43) and the cytidine derivative 2 (EC50 = 0.81 mM, SI50 > 13), respectively. The corresponding thiophosphonates 4'-C-(α)-Me-4'-C-(ß)-(O-CH2 -P( S)(OEt)2 ) and thionopyrimidine nucleosides were devoid of any antiviral activity. This study shows that the 4'-C-(α)-Me-4'-(ß)-O-CH2 -P(═O)(OEt)2 ribonucleoside can be further optimized to provide potent antiviral agents.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Nucleosídeos de Pirimidina , Ribonucleosídeos , Humanos , Relação Estrutura-Atividade , Antivirais/farmacologia
15.
Molecules ; 28(17)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37687255

RESUMO

Plant-derived phytochemicals have recently drawn interest in the prevention and treatment of diabetes mellitus (DM). The seeds of Moringa oleifera Lam. are widely used in food and herbal medicine for their health-promoting properties against various diseases, including DM, but many of their effective constituents are still unknown. In this study, 6 new phenolic glycosides, moringaside B-G (1-6), together with 10 known phenolic glycosides (7-16) were isolated from M. oleifera seeds. The structures were elucidated by 1D and 2D NMR spectroscopy and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) data analysis. The absolute configurations of compounds 2 and 3 were determined by electronic circular dichroism (ECD) calculations. Compounds 2 and 3 especially are combined with a 1,3-dioxocyclopentane moiety at the rhamnose group, which are rarely reported in phenolic glycoside backbones. A biosynthetic pathway of 2 and 3 was assumed. Moreover, all the isolated compounds were evaluated for their inhibitory activities against α-glucosidase. Compounds 4 and 16 exhibited marked activities with IC50 values of 382.8 ± 1.42 and 301.4 ± 6.22 µM, and the acarbose was the positive control with an IC50 value of 324.1 ± 4.99 µM. Compound 16 revealed better activity than acarbose.


Assuntos
Glicosídeos , Moringa oleifera , Glicosídeos/farmacologia , alfa-Glucosidases , Acarbose , Sementes , Fenóis/farmacologia
16.
BMC Nurs ; 22(1): 457, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049804

RESUMO

BACKGROUND: Coronary heart disease (CHD) is a cardiovascular disease with high mortality. At present, percutaneous coronary intervention (PCI) is considered as the main effective treatment for CHD due to less trauma, shorter course of treatment, and better curative effect. However, PCI alone is not a permanent cure, so cardiac rehabilitation (CR) is needed for a supplement. Nowadays, the evaluation of the nursing-sensitive quality of CR after PCI focuses on the outcomes of patients, lacks a complete evaluation indicator system, and is prone to problems such as nursing management imbalance. OBJECTIVE: A scientific, sensitive, comprehensive and practical nursing-sensitive quality indicator system based on the structure-process-outcome model was constructed to provide a reference for evaluating nursing-sensitive quality of CR after PCI. METHODS: Firstly, through literature analysis and semi-structured interview, the indicator system was collected, screened and determined. Then, the framework of the indicator system was established, and the draft of nursing-sensitive quality indicator system of CR after PCI was formed. Subsequently, the nursing-sensitive quality indicator system of CR after PCI was initially established using Delphi method. Finally, the specific weight was determined by analytic hierarchy process (AHP), and the nursing-sensitive quality indicator system of CR after PCI was established and perfected. RESULTS: Two rounds of expert consultations were separately given 15 questionnaires, and all these questionnaires were returned, with a questionnaire response rate of 100%. Such result indicated that experts were highly motivated. Besides, the authoritative coefficients for two rounds of expert consultations were 0.865 and 0.888, and the coordination coefficients were 0.491 and 0.522, respectively. Hence, the experts' authority and coordination were high and the results were reliable. After the second round of expert consultation, the nursing-sensitive quality indicator system of CR after PCI was established, eventually. This system consisted of 3 first-level indicators (structural indicator, process indicator and outcome indicator), 11 s-level indicators and 29 third-level indicators. CONCLUSION: A relatively complete and reliable nursing-sensitive quality indicator system of CR after PCI has been established in this study. Such system is scientific and reliable and can provide a reference for the evaluation of clinical teaching quality of CR after PCI.

17.
Zhonghua Nan Ke Xue ; 29(9): 810-814, 2023 Sep.
Artigo em Zh | MEDLINE | ID: mdl-38639593

RESUMO

OBJECTIVE: To evaluate the therapeutic effects of Xuanju compound capsule combined with urofollitropin (uFSH) in the treatment of idiopathic oligoasthenozoospermia. METHODS: From June 2022 to June 2023, patients with idiopathic oligoastheospermia were enrolled in this study, and divided into trail group (Xuanju compound capsule combined with urofollitropin tablets, n=53) and control group (urofollitropin tablets, n=61) according to the difference in treatment. Treatment methods: Xuanju compound capsule, 3 pills, three times a day; Urofollitropin, 75IU, one times three day. The curses of treatments for control group and trail group is 12 weeks. In order to evaluate the therapeutic effects of control group and trial group, semen volume, sperm concentration, progressive sperm ratio (PR), peripheral serum sex hormone, liver functions were analyzed before and after treatment for two times. RESULTS: Compared with the baseline, the semen volume and liver function were not significantly changed after the treatment in control group and trial group. However, sperm concentration, PR, testosterone (T) levels, follicle stimulating hormone (FSH) levels, and luteinizing hormone (LH) levels were significantly unregulated after the treatment in control group and trial group. More importantly, compared to control group, sperm concentration, PR, T leves, FSH levels, LH levels, and T/E2 ratio of trial group were further enhanced after the treatment, which were statistically significant (P < 0.05). CONCLUSIONS: Xuanju compound capsule combined with urofollitropin tablets could significantly improve the semen quality, up-regulate the testosterone levels and T/E2 ratio in patients with idiopathic oligoasthenozoospermia.


Assuntos
Urofolitropina , Humanos , Masculino , Hormônio Foliculoestimulante , Sêmen , Análise do Sêmen , Contagem de Espermatozoides , Testosterona , Resultado do Tratamento , Urofolitropina/uso terapêutico
18.
Hum Mutat ; 43(10): 1472-1489, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35815345

RESUMO

Aminoacyl-tRNA synthetases (ARSs) are essential enzymes for faithful assignment of amino acids to their cognate tRNA. Variants in ARS genes are frequently associated with clinically heterogeneous phenotypes in humans and follow both autosomal dominant or recessive inheritance patterns in many instances. Variants in tryptophanyl-tRNA synthetase 1 (WARS1) cause autosomal dominantly inherited distal hereditary motor neuropathy and Charcot-Marie-Tooth disease. Presently, only one family with biallelic WARS1 variants has been described. We present three affected individuals from two families with biallelic variants (p.Met1? and p.(Asp419Asn)) in WARS1, showing varying severities of developmental delay and intellectual disability. Hearing impairment and microcephaly, as well as abnormalities of the brain, skeletal system, movement/gait, and behavior were variable features. Phenotyping of knocked down wars-1 in a Caenorhabditis elegans model showed depletion is associated with defects in germ cell development. A wars1 knockout vertebrate model recapitulates the human clinical phenotypes, confirms variant pathogenicity, and uncovers evidence implicating the p.Met1? variant as potentially impacting an exon critical for normal hearing. Together, our findings provide consolidating evidence for biallelic disruption of WARS1 as causal for an autosomal recessive neurodevelopmental syndrome and present a vertebrate model that recapitulates key phenotypes observed in patients.


Assuntos
Aminoacil-tRNA Sintetases , Doença de Charcot-Marie-Tooth , Triptofano-tRNA Ligase , Aminoacil-tRNA Sintetases/genética , Doença de Charcot-Marie-Tooth/genética , Éxons , Humanos , Mutação , Linhagem , RNA de Transferência/genética , Síndrome , Triptofano-tRNA Ligase/genética
19.
Hum Mutat ; 43(10): 1454-1471, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35790048

RESUMO

Aminoacylation of transfer RNA (tRNA) is a key step in protein biosynthesis, carried out by highly specific aminoacyl-tRNA synthetases (ARSs). ARSs have been implicated in autosomal dominant and autosomal recessive human disorders. Autosomal dominant variants in tryptophanyl-tRNA synthetase 1 (WARS1) are known to cause distal hereditary motor neuropathy and Charcot-Marie-Tooth disease, but a recessively inherited phenotype is yet to be clearly defined. Seryl-tRNA synthetase 1 (SARS1) has rarely been implicated in an autosomal recessive developmental disorder. Here, we report five individuals with biallelic missense variants in WARS1 or SARS1, who presented with an overlapping phenotype of microcephaly, developmental delay, intellectual disability, and brain anomalies. Structural mapping showed that the SARS1 variant is located directly within the enzyme's active site, most likely diminishing activity, while the WARS1 variant is located in the N-terminal domain. We further characterize the identified WARS1 variant by showing that it negatively impacts protein abundance and is unable to rescue the phenotype of a CRISPR/Cas9 wars1 knockout zebrafish model. In summary, we describe two overlapping autosomal recessive syndromes caused by variants in WARS1 and SARS1, present functional insights into the pathogenesis of the WARS1-related syndrome and define an emerging disease spectrum: ARS-related developmental disorders with or without microcephaly.


Assuntos
Aminoacil-tRNA Sintetases , Doença de Charcot-Marie-Tooth , Microcefalia , Triptofano-tRNA Ligase , Animais , Humanos , Aminoacil-tRNA Sintetases/genética , Doença de Charcot-Marie-Tooth/genética , Ligases , Microcefalia/genética , Microcefalia/patologia , RNA de Transferência , Triptofano-tRNA Ligase/genética , Peixe-Zebra/genética
20.
Chembiochem ; 23(15): e202200089, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35662372

RESUMO

Natural RNA modifications diversify the structures and functions of existing nucleic acid building blocks. Geranyl is one of the most hydrophobic groups recently identified in bacterial tRNAs. Selenouridine synthase (SelU, also called mnmH) is an enzyme with a dual activity which catalyzes selenation and geranylation in tRNAs containing 2-thiouridine using selenophosphate or geranyl-pyrophosphate as cofactors. In this study, we explored the in vitro geranylation process of tRNA anticodon stem loops (ASL) mediated by SelU and showed that the geranylation activity was abolished when U35 was mutated to A35 (ASL-tRNALys (s2U)UU to ASL-tRNAIle (s2U)AU ). By examining the SelU cofactor geranyl-pyrophosphate (gePP) and its analogues, we found that only the geranyl group, but not dimethylallyl- and farnesyl-pyrophosphate with either shorter or longer terpene chains, could be incorporated into ASL. The degree of tRNA geranylation in the end-point analysis for SelU follows the order of ASLLys (s2UUU) ≃ ASLGln (s2UUG) >ASLGlu (s2UUC) . These findings suggest a putative mechanism for substrate discrimination by SelU and reveal key factors that might influence its enzymatic activity. Given that SelU plays an important role in bacterial translation systems, inhibiting this enzyme and targeting its geranylation and selenation pathways could be exploited as a promising strategy to develop SelU-based antibiotics.


Assuntos
Difosfatos , RNA de Transferência , Anticódon , Conformação de Ácido Nucleico , RNA de Transferência/química , Terpenos/metabolismo
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