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1.
Nat Ecol Evol ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39025981

RESUMEN

The common ancestor of all vertebrates had a highly sophisticated nervous system, but questions remain about the evolution of vertebrate neural cell types. The amphioxus, a chordate that diverged before the origin of vertebrates, can inform vertebrate evolution. Here we develop and analyse a single-cell RNA-sequencing dataset from seven amphioxus embryo stages to understand chordate cell type evolution and to study vertebrate neural cell type origins. We identified many new amphioxus cell types, including homologues to the vertebrate hypothalamus and neurohypophysis, rooting the evolutionary origin of these structures. On the basis of ancestor-descendant reconstruction of cell trajectories of the amphioxus and other species, we inferred expression dynamics of transcription factor genes throughout embryogenesis and identified three ancient developmental routes forming chordate neurons. We characterized cell specification at the mechanistic level and generated mutant lines to examine the function of five key transcription factors involved in neural specification. Our results show three developmental origins for the vertebrate nervous system: an anterior FoxQ2-dependent mechanism that is deeply conserved in invertebrates, a less-conserved route leading to more posterior neurons in the vertebrate spinal cord and a mechanism for specifying neuromesoderm progenitors that is restricted to chordates. The evolution of neuromesoderm progenitors may have led to a dramatic shift in posterior neural and mesodermal cell fate decisions and the body elongation process in a stem chordate.

2.
QJM ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38837343

RESUMEN

BACKGROUND: Maple Syrup Urine Disease (MSUD) is an autosomal recessive metabolic disorder originating from defects in the branched-chain α-ketoacid dehydrogenase (BCKDH) complex encoded by BCKDHA, BCKDHB, and DBT. This condition presents a spectrum of symptoms and potentially fatal outcomes. Although numerous mutations in the BCKDH complex genes associated with MSUD have been identified, the relationship between specific genotypes remains to be fully elucidated. AIM: Our objective was to predict the pathogenicity of these genetic mutations and establish potential links between genotypic alterations and the clinical phenotypes of MSUD. DESIGN: Retrospective population-based cohort. METHODS: We analyzed 20 MSUD patients from the Children's Hospital at Zhejiang University School of Medicine (Hangzhou, China), recorded from January 2010 to May 2023. Patients' blood samples were collected by heel-stick through neonatal screening, and amino acid profiles were measured by tandem mass spectrometry. In silico methods were employed to assess the pathogenicity, stability, and biophysical properties. Various computation tools were utilized for assessment, namely PredictSNP, MAGPIE, iStable, Align GVGD, ConSurf and SNP effect. RESULTS: We detected 25 distinct mutations, including 12 novel mutations. The BCKDHB gene was the most commonly affected (53.3%) compared to the BCKDHA gene (20.0%) and DBT gene (26.7%). In silico webservers predicted all novel mutations were disease-causing. CONCLUSIONS: This study highlights the genetic complexity of MSUD and underscores the importance of early detection and intervention. Integrating neonatal screening with advanced sequencing methodologies is pivotal in ensuring precise diagnosis and effective management of MSUD, thereby significantly improving the prognosis for individuals afflicted with this condition.

3.
Fitoterapia ; 177: 106089, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38906384

RESUMEN

Daphne genkwa, as a traditional medicine, is widely distributed in China, Korea and Vietnam. In China, the dried flower buds of this plant are named "Yuanhua". It has the ability to effectively promote urination, eliminate phlegm and alleviate cough, eliminate parasites and cure of scabies, with a broad spectrum of pharmacological effects and considerable clinical efficacy. This paper provides a summary and classification of the main chemical constituents of D. genkwa based on a review of relevant domestic and foreign literature. It also outlines the current research status of traditional clinical usage, pharmacological effects, and toxicity of D. genkwa. The aim is to provide a theoretical basis for further study of D. genkwa and its potential new clinical applications.


Asunto(s)
Daphne , Etnofarmacología , Fitoquímicos , Daphne/química , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Humanos , Medicina Tradicional China , Estructura Molecular , China , Flores/química , Animales , Vietnam
4.
Angew Chem Int Ed Engl ; 63(30): e202316755, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38739420

RESUMEN

The hydrazine oxidation-assisted H2 evolution method promises low-input and input-free hydrogen production. However, developing high-performance catalysts for hydrazine oxidation (HzOR) and hydrogen evolution (HER) is challenging. Here, we introduce a bifunctional electrocatalyst α-MoC/N-C/RuNSA, merging ruthenium (Ru) nanoclusters (NCs) and single atoms (SA) into cubic α-MoC nanoparticles-decorated N-doped carbon (α-MoC/N-C) nanowires, through electrodeposition. The composite showcases exceptional activity for both HzOR and HER, requiring -80 mV and -9 mV respectively to reach 10 mA cm-2. Theoretical and experimental insights confirm the importance of two Ru species for bifunctionality: NCs enhance the conductivity, and its coexistence with SA balances the H ad/desorption for HER and facilitates the initial dehydrogenation during the HzOR. In the overall hydrazine splitting (OHzS) system, α-MoC/N-C/RuNSA excels as both anode and cathode materials, achieving 10 mA cm-2 at just 64 mV. The zinc hydrazine (Zn-Hz) battery assembled with α-MoC/N-C/RuNSA cathode and Zn foil anode can exhibit 97.3 % energy efficiency, as well as temporary separation of hydrogen gas during the discharge process. Therefore, integrating Zn-Hz with OHzS system enables self-powered H2 evolution, even in hydrazine sewage. Overall, the amalgamation of NCs with SA achieves diverse catalytic activities for yielding multifold hydrogen gas through advanced cell-integrated-electrolyzer system.

5.
Nat Commun ; 15(1): 3588, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38678013

RESUMEN

Eye tracking techniques enable high-efficient, natural, and effortless human-machine interaction by detecting users' eye movements and decoding their attention and intentions. Here, a miniature, imperceptible, and biocompatible smart contact lens is proposed for in situ eye tracking and wireless eye-machine interaction. Employing the frequency encoding strategy, the chip-free and battery-free lens successes in detecting eye movement and closure. Using a time-sequential eye tracking algorithm, the lens has a great angular accuracy of <0.5°, which is even less than the vision range of central fovea. Multiple eye-machine interaction applications, such as eye-drawing, Gluttonous Snake game, web interaction, pan-tilt-zoom camera control, and robot vehicle control, are demonstrated on the eye movement model and in vivo rabbit. Furthermore, comprehensive biocompatibility tests are implemented, demonstrating low cytotoxicity and low eye irritation. Thus, the contact lens is expected to enrich approaches of eye tracking techniques and promote the development of human-machine interaction technology.


Asunto(s)
Algoritmos , Lentes de Contacto , Movimientos Oculares , Tecnología de Seguimiento Ocular , Movimientos Oculares/fisiología , Animales , Humanos , Conejos , Sistemas Hombre-Máquina
6.
BMC Med Imaging ; 24(1): 58, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38443786

RESUMEN

BACKGROUND: MULTIPLEX is a single-scan three-dimensional multi-parametric MRI technique that provides 1 mm isotropic T1-, T2*-, proton density- and susceptibility-weighted images and the corresponding quantitative maps. This study aimed to investigate its feasibility of clinical application in Parkinson's disease (PD). METHODS: 27 PD patients and 23 healthy control (HC) were recruited and underwent a MULTIPLEX scanning. All image reconstruction and processing were automatically performed with in-house C + + programs on the Automatic Differentiation using Expression Template platform. According to the HybraPD atlas consisting of 12 human brain subcortical nuclei, the region-of-interest (ROI) based analysis was conducted to extract quantitative parameters, then identify PD-related abnormalities from the T1, T2* and proton density maps and quantitative susceptibility mapping (QSM), by comparing patients and HCs. RESULTS: The ROI-based analysis revealed significantly decreased mean T1 values in substantia nigra pars compacta and habenular nuclei, mean T2* value in subthalamic nucleus and increased mean QSM value in subthalamic nucleus in PD patients, compared to HCs (all p values < 0.05 after FDR correction). The receiver operating characteristic analysis showed all these four quantitative parameters significantly contributed to PD diagnosis (all p values < 0.01 after FDR correction). Furthermore, the two quantitative parameters in subthalamic nucleus showed hemicerebral differences in regard to the clinically dominant side among PD patients. CONCLUSIONS: MULTIPLEX might be feasible for clinical application to assist in PD diagnosis and provide possible pathological information of PD patients' subcortical nucleus and dopaminergic midbrain regions.


Asunto(s)
Imágenes de Resonancia Magnética Multiparamétrica , Enfermedad de Parkinson , Humanos , Estudios de Factibilidad , Enfermedad de Parkinson/diagnóstico por imagen , Protones , Dopamina
7.
Brain Behav ; 14(1): e3369, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38376016

RESUMEN

PURPOSE: The motor symptoms (MS) of Parkinson's disease (PD) have been affecting the quality of life in patients. In clinical practice, most patients with PD report that MS are more severe in winter than in summer, and hyperthermic baths (HTB) could temporarily improve MS. The study aimed to evaluate the effects of seasonal variation and aquatic thermal environment of HTB on the MS of PD. PATIENTS AND METHODS: A cross-sectional study of 203 Chinese Han patients was performed. Univariate and multivariate analyses were performed to analyze seasonal variation in MS relative to baseline data (sex, age at onset, duration, season of birth, Hoehn and Yahr stage, family history, levodopa equivalent dose, and the effect of HTB on MS). Ten subjects participated in the HTB study, and one patient dropped out. The paired Wilcoxon rank test was used to assess the differences in the Movement Disorder Society-United Parkinson's disease Rating Scale (MDS-UPDRS) part III motor examination total scores and the modified Webster Symptoms Score between non-HTB and before HTB and between non-HTB and after HTB. RESULTS: The improvement of MS after HTB was an independent risk factor for seasonal variation in MS (OR, 25.203; 95% CI, 10.951-58.006; p = .000). Patients with PD had significant improvements in the MDS-UPDRS part III motor examination total scores, especially in bradykinesia (p = .043), rigidity (p = .008), posture (p = .038), and rest tremor amplitude (p = .047). CONCLUSION: Seasonal variation in temperature and water temperature of HTB may affect MS in some patients with PD. Simple HTB could be recommended as physiotherapy for patients with PD who report temperature-sensitive MS.


Asunto(s)
Enfermedad de Parkinson , Salicilatos , Humanos , Estudios Transversales , Enfermedad de Parkinson/tratamiento farmacológico , Proyectos Piloto , Calidad de Vida , Temperatura
8.
Elife ; 132024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38231024

RESUMEN

A central goal of evolutionary developmental biology is to decipher the evolutionary pattern of gene regulatory networks (GRNs) that control embryonic development, and the mechanism underlying GRNs evolution. The Nodal signaling that governs the body axes of deuterostomes exhibits a conserved GRN orchestrated principally by Nodal, Gdf1/3, and Lefty. Here we show that this GRN has been rewired in cephalochordate amphioxus. We found that while the amphioxus Gdf1/3 ortholog exhibited nearly no embryonic expression, its duplicate Gdf1/3-like, linked to Lefty, was zygotically expressed in a similar pattern as Lefty. Consistent with this, while Gdf1/3-like mutants showed defects in axial development, Gdf1/3 mutants did not. Further transgenic analyses showed that the intergenic region between Gdf1/3-like and Lefty could drive reporter gene expression as that of the two genes. These results indicated that Gdf1/3-like has taken over the axial development role of Gdf1/3 in amphioxus, possibly through hijacking Lefty enhancers. We finally demonstrated that, to compensate for the loss of maternal Gdf1/3 expression, Nodal has become an indispensable maternal factor in amphioxus and its maternal mutants caused axial defects as Gdf1/3-like mutants. We therefore demonstrated a case that the evolution of GRNs could be triggered by enhancer hijacking events. This pivotal event has allowed the emergence of a new GRN in extant amphioxus, presumably through a stepwise process. In addition, the co-expression of Gdf1/3-like and Lefty achieved by a shared regulatory region may have provided robustness during body axis formation, which provides a selection-based hypothesis for the phenomena called developmental system drift.


Asunto(s)
Redes Reguladoras de Genes , Anfioxos , Femenino , Animales , Anfioxos/genética , Animales Modificados Genéticamente , ADN Intergénico , Desarrollo Embrionario , Factor de Crecimiento Transformador beta
9.
Nat Commun ; 15(1): 842, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287016

RESUMEN

The constant emergence of SARS-CoV-2 variants continues to impair the efficacy of existing neutralizing antibodies, especially XBB.1.5 and EG.5, which showed exceptional immune evasion properties. Here, we identify a highly conserved neutralizing epitope targeted by a broad-spectrum neutralizing antibody BA7535, which demonstrates high neutralization potency against not only previous variants, such as Alpha, Beta, Gamma, Delta and Omicron BA.1-BA.5, but also more recently emerged Omicron subvariants, including BF.7, CH.1.1, XBB.1, XBB.1.5, XBB.1.9.1, EG.5. Structural analysis of the Omicron Spike trimer with BA7535-Fab using cryo-EM indicates that BA7535 recognizes a highly conserved cryptic receptor-binding domain (RBD) epitope, avoiding most of the mutational hot spots in RBD. Furthermore, structural simulation based on the interaction of BA7535-Fab/RBD complexes dissects the broadly neutralizing effect of BA7535 against latest variants. Therapeutic and prophylactic treatment with BA7535 alone or in combination with BA7208 protected female mice from the circulating Omicron BA.5 and XBB.1 variant infection, suggesting the highly conserved neutralizing epitope serves as a potential target for developing highly potent therapeutic antibodies and vaccines.


Asunto(s)
COVID-19 , Femenino , Animales , Humanos , Ratones , SARS-CoV-2/genética , Anticuerpos Neutralizantes , Anticuerpos ampliamente neutralizantes , Epítopos/genética , Anticuerpos Antivirales , Glicoproteína de la Espiga del Coronavirus/genética
10.
Front Cell Dev Biol ; 11: 1247067, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38099291

RESUMEN

Introduction: Both low bone mineral density (BMD) and Alzheimer's disease (AD) commonly co_occur in the older adult. Until now, the association between AD and BMD has been widely reported by observational studies. However, Mendelian randomization (MR) studies did not support the causal association between BMD and AD. We think that the lack of significant causal association between AD and BMD identified by recent MR studies may be caused by small number of potential instrumental variables. Methods: We conduct a MR study to evaluate the causal effect of heel BMD on the risk of AD using 1,362 genome-wide significant and independent (p < 5.00E-08) heel BMD genetic variants as the potential instrumental variables, which are identified by a large-scale genome wide association study (GWAS) of heel BMD in 394,929 UK Biobank individuals. Using these 1,362 genome-wide significant and independent heel BMD genetic variants, we extracted their corresponding AD GWAS summary results in IGAP AD GWAS dataset (n = 63,926) and FinnGen AD GWAS dataset (n = 377,277). Five methods including inverse-variance weighted meta-analysis (IVW), weighted median, MR-Egger, MR-PRESSO, and MRlap were selected to perform the MR analysis. 951 of these 1,362 genetic variants are available in AD GWAS dataset. Results: We observed statistically significant causal effect of heel BMD on the risk of AD using IVW in IGAP AD GWAS dataset (OR = 1.048, 95%CI: 1.002-1.095, p = 0.04) and FinnGen AD GWAS dataset (OR = 1.053, 95% CI:1.011-1.098, p = 0.011). Importantly, meta-analysis of IVW estimates from IGAP and FinnGen further supported the causal effect of heel BMD on the risk of AD (OR = 1.051, 95% CI: 1.02-1.083, p = 0.0013). Discussion: Collectively, our current MR study supports heel BMD to be a risk factor of AD by analyzing the large-scale heel BMD and AD GWAS datasets. The potential mechanisms underlying the association between heel BMD and AD should be further evaluated in future.

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