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1.
Nature ; 631(8022): 826-834, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38987597

RESUMEN

Glutamate is traditionally viewed as the first messenger to activate NMDAR (N-methyl-D-aspartate receptor)-dependent cell death pathways in stroke1,2, but unsuccessful clinical trials with NMDAR antagonists implicate the engagement of other mechanisms3-7. Here we show that glutamate and its structural analogues, including NMDAR antagonist L-AP5 (also known as APV), robustly potentiate currents mediated by acid-sensing ion channels (ASICs) associated with acidosis-induced neurotoxicity in stroke4. Glutamate increases the affinity of ASICs for protons and their open probability, aggravating ischaemic neurotoxicity in both in vitro and in vivo models. Site-directed mutagenesis, structure-based modelling and functional assays reveal a bona fide glutamate-binding cavity in the extracellular domain of ASIC1a. Computational drug screening identified a small molecule, LK-2, that binds to this cavity and abolishes glutamate-dependent potentiation of ASIC currents but spares NMDARs. LK-2 reduces the infarct volume and improves sensorimotor recovery in a mouse model of ischaemic stroke, reminiscent of that seen in mice with Asic1a knockout or knockout of other cation channels4-7. We conclude that glutamate functions as a positive allosteric modulator for ASICs to exacerbate neurotoxicity, and preferential targeting of the glutamate-binding site on ASICs over that on NMDARs may be strategized for developing stroke therapeutics lacking the psychotic side effects of NMDAR antagonists.


Asunto(s)
Canales Iónicos Sensibles al Ácido , Isquemia Encefálica , Ácido Glutámico , Animales , Femenino , Humanos , Masculino , Ratones , 2-Amino-5-fosfonovalerato/efectos adversos , 2-Amino-5-fosfonovalerato/metabolismo , 2-Amino-5-fosfonovalerato/farmacología , Canales Iónicos Sensibles al Ácido/química , Canales Iónicos Sensibles al Ácido/deficiencia , Canales Iónicos Sensibles al Ácido/efectos de los fármacos , Canales Iónicos Sensibles al Ácido/genética , Canales Iónicos Sensibles al Ácido/metabolismo , Regulación Alostérica/efectos de los fármacos , Sitios de Unión/genética , Isquemia Encefálica/inducido químicamente , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Ácido Glutámico/análogos & derivados , Ácido Glutámico/metabolismo , Ácido Glutámico/farmacología , Ácido Glutámico/toxicidad , Ratones Noqueados , Mutagénesis Sitio-Dirigida , Protones , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/metabolismo
2.
J Neurosci ; 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39313321

RESUMEN

Hyperbilirubinemia (HB) is a key risk factor for hearing loss in neonates, particularly premature infants. Here we report that bilirubin (BIL)-dependent cell death in auditory brainstem of neonatal mice of both sexes is significantly attenuated by ZD7288, a blocker for hyperpolarization-activated cyclic nucleotide-gated (HCN) channel mediated current (Ih), or by genetic deletion of HCN1. GABAergic inhibitory interneurons predominantly express HCN1, on which BIL selectively acts to increase their intrinsic excitability and mortality by enhancing HCN1 activity and Ca2+-dependent membrane targeting. Chronic BIL elevation in neonatal mice in vivo increases the fraction of spontaneously active interneurons and their firing frequency, Ih and death, compromising audition at young adult stage in HCN1+/+, but not in HCN1-/- genotype. We conclude that HB preferentially targets HCN1 to injure inhibitory interneurons, fueling a feedforward loop in which lessening inhibition cascades hyperexcitability, Ca2+ overload, neuronal death and auditory impairments. These findings rationalize HCN1 as a potential target for managing HB encephalopathy.Significance Statement This study demonstrated that bilirubin preferentially targets GABAergic interneurons where it facilitates not only gating of HCN1 channels but also targeting of intracellular HCN1 to plasma membrane in calcium-dependent manner, resulting in neuronal hyperexcitability, injury and sensory dysfunction. These findings implicate HCN1 channel not only as a potential driver for auditory abnormalities in neonatal patients with bilirubin encephalopathy, but also potential intervention target for clinical management of neurological impairments associated with severe jaundice. Selective vulnerability of interneurons to neurotoxicity may be of general significance for understanding other forms of brain injury.

3.
J Biol Chem ; 300(8): 107556, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39002683

RESUMEN

Diversity, a hallmark of G protein-coupled receptor (GPCR) signaling, partly stems from alternative splicing of a single gene generating more than one isoform for a receptor. Additionally, receptor responses to ligands can be attenuated by desensitization upon prolonged or repeated ligand exposure. Both phenomena have been demonstrated and exemplified by the deuterostome tachykinin signaling system, although the role of phosphorylation in desensitization remains a subject of debate. Here, we describe the signaling system for tachykinin-related peptides (TKRPs) in a protostome, mollusk Aplysia. We cloned the Aplysia TKRP precursor, which encodes three TKRPs (apTKRP-1, apTKRP-2a, and apTKRP-2b) containing the FXGXR-amide motif. In situ hybridization and immunohistochemistry showed predominant expression of TKRP mRNA and peptide in the cerebral ganglia. TKRPs and their posttranslational modifications were observed in extracts of central nervous system ganglia using mass spectrometry. We identified two Aplysia TKRP receptors (apTKRPRs), named apTKRPR-A and apTKRPR-B. These receptors are two isoforms generated through alternative splicing of the same gene and differ only in their intracellular C termini. Structure-activity relationship analysis of apTKRP-2b revealed that both C-terminal amidation and conserved residues of the ligand are critical for receptor activation. C-terminal truncates and mutants of apTKRPRs suggested that there is a C-terminal phosphorylation-independent desensitization for both receptors. Moreover, apTKRPR-B also exhibits phosphorylation-dependent desensitization through the phosphorylation of C-terminal Ser/Thr residues. This comprehensive characterization of the Aplysia TKRP signaling system underscores the evolutionary conservation of the TKRP and TK signaling systems, while highlighting the intricacies of receptor regulation through alternative splicing and differential desensitization mechanisms.


Asunto(s)
Aplysia , Isoformas de Proteínas , Animales , Aplysia/metabolismo , Fosforilación , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/genética , Receptores de Taquicininas/metabolismo , Receptores de Taquicininas/genética , Taquicininas/metabolismo , Taquicininas/genética , Secuencia de Aminoácidos , Transducción de Señal , Empalme Alternativo , Humanos
4.
Circulation ; 150(13): 981-993, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39166327

RESUMEN

BACKGROUND: Colchicine has been approved to reduce cardiovascular risk in patients with coronary heart disease on the basis of its potential benefits demonstrated in the COLCOT (Colchicine Cardiovascular Outcomes Trial) and LoDoCo2 (Low-Dose Colchicine 2) studies. Nevertheless, there are limited data available about the specific impact of colchicine on coronary plaques. METHODS: This was a prospective, single-center, randomized, double-blind clinical trial. From May 3, 2021, until August 31, 2022, a total of 128 patients with acute coronary syndrome aged 18 to 80 years with lipid-rich plaque (lipid pool arc >90°) detected by optical coherence tomography were included. The subjects were randomly assigned in a 1:1 ratio to receive either colchicine (0.5 mg once daily) or placebo for 12 months. The primary end point was the change in the minimal fibrous cap thickness from baseline to the 12-month follow-up. RESULTS: Among 128 patients, 52 in the colchicine group and 52 in the placebo group completed the study. The mean age of the 128 patients was 58.0±9.8 years, and 25.0% were female. Compared with placebo, colchicine therapy significantly increased the minimal fibrous cap thickness (51.9 [95% CI, 32.8 to 71.0] µm versus 87.2 [95% CI, 69.9 to 104.5] µm; difference, 34.2 [95% CI, 9.7 to 58.6] µm; P=0.006), and reduced average lipid arc (-25.2° [95% CI, -30.6° to -19.9°] versus -35.7° [95% CI, -40.5° to -30.8°]; difference, -10.5° [95% CI, -17.7° to -3.4°]; P=0.004), mean angular extension of macrophages (-8.9° [95% CI, -13.3° to -4.6°] versus -14.0° [95% CI, -18.0° to -10.0°]; difference, -6.0° [95% CI, -11.8° to -0.2°]; P=0.044), high-sensitivity C-reactive protein level (geometric mean ratio, 0.6 [95% CI, 0.4 to 1.0] versus 0.3 [95% CI, 0.2 to 0.5]; difference, 0.5 [95% CI, 0.3 to 1.0]; P=0.046), interleukin-6 level (geometric mean ratio, 0.8 [95% CI, 0.6 to 1.1] versus 0.5 [95% CI, 0.4 to 0.7]; difference, 0.6 [95% CI, 0.4 to 0.9]; P=0.025), and myeloperoxidase level (geometric mean ratio, 1.0 [95% CI, 0.8 to 1.2] versus 0.8 [95% CI, 0.7 to 0.9]; difference, 0.8 [95% CI, 0.6 to 1.0]; P=0.047). CONCLUSIONS: Our findings suggested that colchicine resulted in favorable effects on coronary plaque stabilization at optical coherence tomography in patients with acute coronary syndrome. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04848857.


Asunto(s)
Síndrome Coronario Agudo , Colchicina , Placa Aterosclerótica , Tomografía de Coherencia Óptica , Humanos , Colchicina/uso terapéutico , Femenino , Síndrome Coronario Agudo/tratamiento farmacológico , Síndrome Coronario Agudo/diagnóstico por imagen , Persona de Mediana Edad , Masculino , Placa Aterosclerótica/tratamiento farmacológico , Placa Aterosclerótica/diagnóstico por imagen , Método Doble Ciego , Anciano , Estudios Prospectivos , Adulto , Resultado del Tratamiento , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Enfermedad de la Arteria Coronaria/diagnóstico por imagen
5.
Nat Mater ; 23(9): 1193-1199, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39080501

RESUMEN

The question of whether all materials can solidify into the glassy form proposed by Turnbull half a century ago remains unsolved. Some of the simplest systems of monatomic metals have not been vitrified, especially the close-packed face-centred cubic metals. Here we report the vitrification of gold, which is notoriously difficult to be vitrified, and several similar close-packed face-centred cubic and hexagonal metals using a method of picosecond pulsed laser ablation in a liquid medium. The vitrification occurs through the rapid cooling during laser ablation and the inhibition of nucleation by the liquid medium. Using this method, a large number of atomic configurations, including glassy configurations, can be generated simultaneously, from which a stable glass state can be sampled. Simulations demonstrate that the favourable stability of monatomic metals stems from the strong topological frustration of icosahedra-like clusters. Our work breaks the limitation of the glass-forming ability of matter, indicating that vitrification is an intrinsic property of matter and providing a strategy for the preparation and design of metallic glasses from an atomic configuration perspective.

6.
Mol Ther ; 32(3): 637-645, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38204163

RESUMEN

N-Acetylgalactosamine (GalNAc)-conjugated small interfering RNA (siRNA) therapies have received approval for treating both orphan and prevalent diseases. To improve in vivo efficacy and streamline the chemical synthesis process for efficient and cost-effective manufacturing, we conducted this study to identify better designs of GalNAc-siRNA conjugates for therapeutic development. Here, we present data on redesigned GalNAc-based ligands conjugated with siRNAs against angiopoietin-like 3 (ANGPTL3) and lipoprotein (a) (Lp(a)), two target molecules with the potential to address large unmet medical needs in atherosclerotic cardiovascular diseases. By attaching a novel pyran-derived scaffold to serial monovalent GalNAc units before solid-phase oligonucleotide synthesis, we achieved increased GalNAc-siRNA production efficiency with fewer synthesis steps compared to the standard triantennary GalNAc construct L96. The improved GalNAc-siRNA conjugates demonstrated equivalent or superior in vivo efficacy compared to triantennary GalNAc-conjugated siRNAs.


Asunto(s)
Enfermedades Cardiovasculares , Hepatocitos , Humanos , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/química , Análisis Costo-Beneficio , ARN Bicatenario , Acetilgalactosamina/química , Proteína 3 Similar a la Angiopoyetina
7.
Chem Soc Rev ; 53(12): 6042-6067, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38770558

RESUMEN

A steady stream of material transport based on carriers and channels in living systems plays an extremely important role in normal life activities. Inspired by nature, researchers have extensively applied supramolecular cages in cargo transport because of their unique three-dimensional structures and excellent physicochemical properties. In this review, we will focus on the development of supramolecular cages as carriers and channels for cargo transport in abiotic and biological systems over the past fifteen years. In addition, we will discuss future challenges and potential applications of supramolecular cages in substance transport.

8.
Rep Prog Phys ; 87(10)2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39260394

RESUMEN

Thechirality-controlled two-mode Lipkin-Meshkov-Glick (LMG) modelsare mimicked in a potential hybrid quantum system, involving two ensembles of solid-state spins coupled to a pair of interconnected surface-acoustic-wave cavities. With the assistance of dichromatic classical optical drives featuring chiral designs, it can simulate two-mode LMG-type long-range spin-spin interactions with left-right asymmetry. For applications, this unconventional LMG model can not only engineer both ensembles of collective spins into two-mode spin-squeezed states but also simulate novel quantum critical phenomena and time crystal behaviors, among others. Since this acoustic-based system can generate ion-trap-like interactions without requiring any additional trapping techniques, our work is considered a fresh attempt at realizing chiral quantum manipulation of spin-spin interactions using acoustic hybrid systems.

9.
Small ; 20(5): e2306274, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37759380

RESUMEN

Efficient electrocatalysts capable of operating continuously at industrial ampere-level current densities are crucial for large-scale applications of electrocatalytic water decomposition for hydrogen production. However, long-term industrial overall water splitting using a single electrocatalyst remains a major challenge. Here, bimetallic polyphthalocyanine (FeCoPPc)-anchored Ru nanoclusters, an innovative electrocatalyst comprising the hydrogen evolution reaction (HER) active Ru and the oxygen evolution reaction (OER) active FeCoPPc, engineered for efficient overall water splitting are demonstrated. By density functional theory calculations and systematic experiments, the electrocatalytic coenhancement effect resulting from unique charge redistribution, which synergistically boosts the HER activity of Ru and the OER activity of FeCoPPc by optimizing the adsorption energy of intermediates, is unveiled. As a result, even at a large current density of 2.0 A cm-2 , the catalyst exhibits low overpotentials of 220 and 308 mV, respectively, for HER and OER. It exhibits excellent stability, requiring only 1.88 V of cell voltage to achieve a current density of 2.0 A cm-2 in a 6.0 m KOH electrolyte at 70 °C, with a remarkable operational stability of over 100 h. This work provides a new electrocatalytic coenhancement strategy for the design and synthesis of electrocatalyst, paving the way for industrial-scale overall water splitting applications.

10.
Clin Chem ; 70(6): 820-829, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38517460

RESUMEN

BACKGROUND: Optical genome mapping (OGM) is a novel assay for detecting structural variants (SVs) and has been retrospectively evaluated for its performance. However, its prospective evaluation in prenatal diagnosis remains unreported. This study aimed to prospectively assess the technical concordance of OGM with standard of care (SOC) testing in prenatal diagnosis. METHODS: A prospective cohort of 204 pregnant women was enrolled in this study. Amniotic fluid samples from these women were subjected to OGM and SOC testing, which included chromosomal microarray analysis (CMA) and karyotyping (KT) in parallel. The diagnostic yield of OGM was evaluated, and the technical concordance between OGM and SOC testing was assessed. RESULTS: OGM successfully analyzed 204 cultured amniocyte samples, even with a cell count as low as 0.24 million. In total, 60 reportable SVs were identified through combined OGM and SOC testing, with 22 SVs detected by all 3 techniques. The diagnostic yield for OGM, CMA, and KT was 25% (51/204), 22.06% (45/204), and 18.14% (37/204), respectively. The highest diagnostic yield (29.41%, 60/204) was achieved when OGM and KT were used together. OGM demonstrated a concordance of 95.56% with CMA and 75.68% with KT in this cohort study. CONCLUSIONS: Our findings suggest that OGM can be effectively applied in prenatal diagnosis using cultured amniocytes and exhibits high concordance with SOC testing. The combined use of OGM and KT appears to yield the most promising diagnostic outcomes.


Asunto(s)
Diagnóstico Prenatal , Humanos , Femenino , Embarazo , Estudios Prospectivos , Diagnóstico Prenatal/métodos , Adulto , Cariotipificación , Mapeo Cromosómico , Líquido Amniótico/química , Líquido Amniótico/citología
11.
Ann Surg Oncol ; 31(4): 2443-2450, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37962741

RESUMEN

BACKGROUND: Chemotherapy and chemoradiation have become essential adjuncts to improve the survival of patients with resectable esophageal squamous cell carcinoma (ESCC) in the perioperative period. Although preoperative treatment plus surgery is commonly used, controversy remains regarding the optimal treatment strategy for patients with locally advanced ESCC. METHODS: A retrospective review of clinical stage II and III ESCC patients who underwent esophagectomy at Henan Cancer Hospital between October 2014 and October 2017 was performed. The patients were divided into a neoadjuvant chemotherapy (NAC) group and an adjuvant chemotherapy (AC) group. Propensity score matching (PSM) was used to exclude confounders. Survival was estimated using Kaplan‒Meier analysis and compared by the log-rank test. The Cox proportional hazards regression model was used for both the univariate and multivariate analyses. RESULTS: A total of 684 patients were enrolled, including 365 (53.4%) patients in the NAC group. After PSM, 294 pairs of patients were left. NAC prolonged the OS (not reached versus 57.3 months, P = 0.002) and DFS (57.2 vs. 36.4 months, P = 0.010) and decreased the total rate of recurrence (50.1% vs. 59.2%, P = 0.025) and local recurrence (27.9% vs. 36.7%, P = 0.022) compared with AC. The multivariable analyses showed that NAC plus surgery modality was an independent predictor for improved OS (HR: 0.582, 95% CI: 0.467-0.786, P = 0.001). CONCLUSION: NAC plus surgery prolonged OS and DFS, and significantly decreased the total rate of recurrence compared with surgery plus AC in patients with clinical stage II and III ESCC.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/patología , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/cirugía , Terapia Neoadyuvante , Quimioterapia Adyuvante , Quimioradioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Esofagectomía , Estudios Retrospectivos , Estadificación de Neoplasias
12.
Metabolomics ; 20(4): 74, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38980520

RESUMEN

BACKGROUND AND AIMS: Biopterins, including tetrahydrobiopterin (BH4), dihydrobiopterin (BH2), and biopterin (B), were crucial enzyme cofactors in vivo. Despite their recognized clinical significance, there remain notable research gaps and controversies surrounding experimental outcomes. This study aims to clarify the biopterins-related issues, including analytical art, physiological intervals, and pathophysiological implications. MATERIALS AND METHODS: A novel LC-MS/MS method was developed to comprehensively profile biopterins in plasma, utilizing chemical derivatization and cold-induced phase separation. Subsequently, apparently healthy individuals were enrolled to investigate the physiological ranges. And the relationships between biopterins and biochemical indicators were analyzed to explore the pathophysiological implications. RESULTS: The developed method was validated as reliable for detecting biopterins across the entire physiological range. Timely anti-oxidation was found to be essential for accurate assessment of biopterins. The observed overall mean ± SDs levels were 3.51 ± 0.94, 1.54 ± 0.48, 2.45 ± 0.84 and 5.05 ± 1.14 ng/mL for BH4, BH2, BH4/BH2 and total biopterins. The status of biopterins showed interesting correlations with age, gender, hyperuricemia and overweight. CONCLUSION: In conjunction with proper anti-oxidation, the newly developed method enables accurate determination of biopterins status in plasma. The observed physiological intervals and pathophysiological implications provide fundamental yet inspiring support for further clinical researches.


Asunto(s)
Biopterinas , Espectrometría de Masas en Tándem , Humanos , Biopterinas/análogos & derivados , Biopterinas/sangre , Biopterinas/metabolismo , Femenino , Masculino , Adulto , Espectrometría de Masas en Tándem/métodos , Persona de Mediana Edad , Cromatografía Liquida/métodos , Adulto Joven , Anciano , Biomarcadores/sangre
13.
Opt Lett ; 49(11): 2966-2969, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824304

RESUMEN

Over the past decades, spin qubits in silicon carbide (SiC) have emerged as promising platforms for a wide range of quantum technologies. The fluorescence intensity holds significant importance in the performance of quantum photonics, quantum information process, and sensitivity of quantum sensing. In this work, a dual-layer Au/SiO2 dielectric cavity is employed to enhance the fluorescence intensity of a shallow silicon vacancy ensemble in 4H-SiC. Experimental results demonstrate an effective fourfold augmentation in fluorescence counts at saturating laser power, corroborating our theoretical predictions. Based on this, we further investigate the influence of dielectric cavities on the contrast and linewidth of optically detected magnetic resonance (ODMR). There is a 1.6-fold improvement in magnetic field sensitivity. In spin echo experiments, coherence times remain constant regardless of the thickness of dielectric cavities. These experiments pave the way for broader applications of dielectric cavities in SiC-based quantum technologies.

14.
Analyst ; 149(2): 546-552, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38088105

RESUMEN

An ultrasensitive fluorescent biosensor is reported for glucose detection based on a Fenton-like reaction triggered chemical redox-cycling signal amplification strategy. In this amplified strategy, Cu2+ oxidizes chemically o-phenylenediamine (OPD) to generate photosensitive 2,3-diaminophenazine (DAP) and Cu+/Cu0. On the one hand, the generated Cu0 catalyzes the oxidation of OPD. On the other hand, H2O2 reacts with Cu+ to produce hydroxyl radicals (˙OH) and Cu2+ through a Cu+-mediated Fenton-like reaction. The generated ˙OH and recycled Cu2+ ions take turns oxidizing OPD to produce more photoactive DAP, triggering a self-sustaining chemical redox-cycling reaction and a remarkable fluorescent enhancement. It is worth mentioning that the cascade reaction did not stop until OPD molecules were completely consumed. Benefiting from H2O2-triggered chemical redox-cycling signal amplification, the strategy was exploited for the development of an ultrasensitive fluorescent biosensor for glucose determination. Glucose content monitoring was realized with a linear range from 1 nM to 1 µM and a limit of detection of 0.3 nM. This study validates the practicability of the chemical redox-cycling signal amplification on the fluorescent bioanalysis of glucose in human serum samples. It is expected that the method offers new opportunities to develop ultrasensitive fluorescent analysis strategy.


Asunto(s)
Glucosa , Peróxido de Hidrógeno , Humanos , Peróxido de Hidrógeno/química , Fluorometría , Oxidación-Reducción , Radical Hidroxilo , Colorantes , Límite de Detección
15.
Phys Chem Chem Phys ; 26(24): 17359-17369, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38860664

RESUMEN

Boron-doped graphdiyne (B-GDY) material exhibits an excellent performance in electrocatalysis, ion transport, and energy storage. However, accurately identifying the structures of B-GDY in experiments remains a challenge, hindering further selection of suitable structures with the most ideal performance for various practical applications. In the present work, we employed density functional theory (DFT) to simulate the X-ray photoelectron spectra (XPS) and near-edge X-ray absorption fine-structure (NEXAFS) spectra of pristine graphdiyne (GDY) and six representative single boron-doped graphdiynes at the B and C K-edges to establish the structure-spectroscopy relationship. A notable disparity in the C 1s ionization potentials (IPs) between substituted and adsorbed structures is observed upon doping with a boron atom. By analyzing the C and B 1s NEXAFS spectra on energy positions, spectral widths, spectral intensities, and different spectral profiles, we found that the six single boron-doped graphdiyne configurations can be sensitively identified. Moreover, this study provides a reliable theoretical reference for distinguishing different single boron-doped graphdiyne structures, enabling accurate selection of B-GDY structures for diverse practical applications.

16.
J Appl Microbiol ; 135(5)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38724452

RESUMEN

AIM: Biotechnical processes in Escherichia coli often operate with artificial plasmids. However, these bioprocesses frequently encounter plasmid loss. To ensure stable expression of heterologous genes in E. coli BL21(DE3), a novel plasmid addiction system (PAS) was developed. METHODS AND RESULTS: This PAS employed an essential gene grpE encoding a cochaperone in the DnaK-DnaJ-GrpE chaperone system as the selection marker, which represented a chromosomal ΔgrpE mutant harboring episomal expression plasmids that carry supplementary grpE alleles to restore the deficiency. To demonstrate the feasibility of this system, it was implemented in phloroglucinol (PG) biosynthesis, manifesting improved host tolerance to PG and increased PG production. Specifically, PG titer significantly improved from 0.78 ± 0.02 to 1.34 ± 0.04 g l-1, representing a 71.8% increase in shake-flask fermentation. In fed-batch fermentation, the titer increased from 3.71 ± 0.11 to 4.54 ± 0.10 g l-1, showing a 22.4% increase. RNA sequencing and transcriptome analysis revealed that the improvements were attributed to grpE overexpression and upregulation of various protective chaperones and the biotin acetyl-CoA carboxylase ligase coding gene birA. CONCLUSION: This novel PAS could be regarded as a typical example of nonanabolite- and nonmetabolite-related PAS. It effectively promoted plasmid maintenance in the host, improved tolerance to PG, and increased the titer of this compound.


Asunto(s)
Proteínas de Escherichia coli , Proteínas de Choque Térmico , Floroglucinol , Plásmidos , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fermentación , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Floroglucinol/metabolismo , Floroglucinol/análogos & derivados , Plásmidos/genética
17.
BMC Cardiovasc Disord ; 24(1): 3, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166569

RESUMEN

BACKGROUND: Aslanger's pattern in electrocardiogram (ECG) indicates that patients may have acute inferior myocardial infarction(AMI) with concomitant critical stenoses on other coronary arteries, which needs to be evaluated the timing of revascularization as risk equivalents of ST elevation myocardial infarction(STEMI). CASE PRESENTATION: The patient was a 62-year-old male with chief complaint of intermittent exertional subxiphoid pain for 20 days from 30th June. One day after the last episode (19th July), the 18-lead electrocardiogram showed ST segment elevation of 0.05-0.1mV in lead III, ST segment depression in leads I, avL, and V2-V6, T wave inversion with positive terminal vector in lead V4-V5, and positive T wave in lead V6, which indicated Aslanger's pattern. With increased Troponin I (0.162ng/mL, 0-0.02), The patient was diagnosed as acute non-ST-segment elevation myocardial infarction (NSTEMI) and admitted to coronary ward on 20th July. The coronary angiography showed 95% stenosis in the distal left main coronary artery (LM) to the ostium of the left anterior descending artery (LAD), 90% stenosis in the proximal segment of the LAD, and 80% stenosis in the middle segment of the LAD, and TIMI blood flow was graded score 2. Three drug-eluting stents were implanted at the lesions. The patient's ECG returned close to normal one month after revascularization. CONCLUSION: We presented an acute coronary syndrome case whose ECG showed with Aslanger's pattern (i.e., isolated ST-segment elevation in lead III, associated ST-segment depression in lead V4-V6 with positive T wave/terminal vector, and greater ST-segment elevation in lead V1 than in lead V2), and was confirmed severe stenosis of the LM and the proximal segment of the LAD via coronary angiography. In clinical practice, especially in the emergency, patients with ECG presenting Aslanger's pattern should be urgently evaluated with prompt treatment, and the timing of emergency coronary angiography and revascularization should be evaluated to avoid adverse outcomes caused by delayed treatment.


Asunto(s)
Infarto del Miocardio , Infarto del Miocardio sin Elevación del ST , Infarto del Miocardio con Elevación del ST , Masculino , Humanos , Persona de Mediana Edad , Constricción Patológica , Infarto del Miocardio/complicaciones , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/terapia , Infarto del Miocardio sin Elevación del ST/diagnóstico por imagen , Infarto del Miocardio sin Elevación del ST/etiología , Angiografía Coronaria , Electrocardiografía , Arritmias Cardíacas
18.
Acta Pharmacol Sin ; 45(3): 465-479, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38017298

RESUMEN

Epilepsy is a prevalent and severe neurological disorder and approximately 30% of patients are resistant to existing medications. It is of utmost importance to develop alternative therapies to treat epilepsy. Schisandrin B (SchB) is a major bioactive constituent of Schisandra chinensis (Turcz.) Baill and has multiple neuroprotective effects, sedative and hypnotic activities. In this study, we investigated the antiseizure effect of SchB in various mouse models of seizure and explored the underlying mechanisms. Pentylenetetrazole (PTZ), strychnine (STR), and pilocarpine-induced mouse seizure models were established. We showed that injection of SchB (10, 30, 60 mg/kg, i.p.) dose-dependently delayed the onset of generalized tonic-clonic seizures (GTCS), reduced the incidence of GTCS and mortality in PTZ and STR models. Meanwhile, injection of SchB (30 mg/kg, i.p.) exhibited therapeutic potential in pilocarpine-induced status epilepticus model, which was considered as a drug-resistant model. In whole-cell recording from CHO/HEK-239 cells stably expressing recombinant human GABAA receptors (GABAARs) and glycine receptors (GlyRs) and cultured hippocampal neurons, co-application of SchB dose-dependently enhanced GABA or glycine-induced current with EC50 values at around 5 µM, and application of SchB (10 µM) alone did not activate the channels in the absence of GABA or glycine. Furthermore, SchB (10 µM) eliminated both PTZ-induced inhibition on GABA-induced current (IGABA) and strychnine (STR)-induced inhibition on glycine-induced current (Iglycine). Moreover, SchB (10 µM) efficiently rescued the impaired GABAARs associated with genetic epilepsies. In addition, the homologous mutants in both GlyRs-α1(S267Q) and GABAARs-α1(S297Q)ß2(N289S)γ2L receptors by site-directed mutagenesis tests abolished SchB-induced potentiation of IGABA and Iglycine. In conclusion, we have identified SchB as a natural positive allosteric modulator of GABAARs and GlyRs, supporting its potential as alternative therapies for epilepsy.


Asunto(s)
Epilepsia , Lignanos , Compuestos Policíclicos , Receptores de Glicina , Ratones , Animales , Humanos , Pilocarpina/efectos adversos , Estricnina/farmacología , Estricnina/uso terapéutico , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico , Receptores de GABA-A , Glicina/farmacología , Hipnóticos y Sedantes , Ácido gamma-Aminobutírico , Ciclooctanos
19.
BMC Pregnancy Childbirth ; 24(1): 325, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671408

RESUMEN

BACKGROUND: Congenital heart disease (CHD) is the predominant birth defect. This study aimed to explore the association between maternal cardiovascular health (CVH) and the CHD risk in offspring. METHODS: We used the prospective data from the Fujian Birth Cohort Study, collected from March 2019 to December 2022 on pregnant women within 14 weeks of gestation. Overall maternal CVH was assessed by seven CVH metrics (including physical activity, smoking, sleep duration, body mass index, blood pressure, total cholesterol, and fasting plasma glucose), with each metric classified as ideal, intermediate or poor with specific points. Participants were further allocated into high, moderate and low CVH categories based on the cumulative CVH score. The association with offspring CHD was determined with log-binominal regression models. RESULTS: A total of 19810 participants aged 29.7 (SD: 3.9) years were included, with 7846 (39.6%) classified as having high CVH, 10949 (55.3%) as having moderate CVH, and 1015 (5.1%) as having low CVH. The average offspring CHD rate was 2.52%, with rates of 2.35%, 2.52% and 3.84% across the high, moderate and low CVH categories, respectively (P = 0.02). Adjusted relative risks (RRs) of having offspring CHD were 0.64 (95% CI: 0.45-0.90, P = 0.001) for high CVH and 0.67 (95% CI: 0.48-0.93, P = 0.02) for moderate CVH compared to low CVH. For individual metrics, only ideal total cholesterol was significantly associated with lower offspring CHD (RR: 0.73, 95% CI: 0.59-0.83, P = 0.002). CONCLUSIONS: Pregnant women of high or moderate CVH categories in early pregnancy had reduced risks of CHD in offspring, compared to those of low CVH. It is important to monitor and improve CVH during pre-pregnancy counseling and early prenatal care.


Asunto(s)
Cardiopatías Congénitas , Humanos , Femenino , Embarazo , Cardiopatías Congénitas/epidemiología , Adulto , Estudios Prospectivos , China/epidemiología , Factores de Riesgo , Cohorte de Nacimiento , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Salud Materna/estadística & datos numéricos , Complicaciones Cardiovasculares del Embarazo/epidemiología
20.
Med Sci Monit ; 30: e942832, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38321725

RESUMEN

BACKGROUND Hypertriglyceridemia-induced acute pancreatitis (HTG-AP), representing 10% of all acute pancreatitis cases, is characterized by younger onset age and more severe progression, often leading to higher ICU admission rates. This condition poses a significant challenge due to its rapid progression and the potential for severe complications, including multiple organ failure. HTG-AP is distinct from other forms of pancreatitis, such as those caused by cholelithiasis or alcohol, in terms of clinical presentation and outcomes. It's essential to identify early markers that can predict the severity of HTG-AP to improve patient management and outcomes. MATERIAL AND METHODS This study divided 127 HTG-AP patients into mild acute pancreatitis (MAP, n=71) and moderate-to-severe acute pancreatitis (MSAP/SAP, n=56) groups. Blood biological indicators within the first 24 hours of admission were analyzed. Risk factors for HTG-AP progression were determined using binary logistic regression and ROC curves. RESULTS Elevated levels of HCT, NLR, TBI, DBI, AST, Cre, and AMS were noted in the MSAP/SAP group, with lower levels of LYM, Na⁺, Ca²âº, ApoA, and ApoB compared to the MAP group (p<0.05). NEUT%, Ca²âº, ApoA, and ApoB were significantly linked with HTG-AP severity. Their combined ROC analysis yielded an area of 0.81, with a sensitivity of 61.8% and specificity of 90%. CONCLUSIONS NEUT%, Ca²âº, ApoA, and ApoB are significant risk factors for progressing to MSAP/SAP in HTG-AP. Their combined assessment provides a reliable predictive measure for early intervention in patients at risk of severe progression.


Asunto(s)
Hipertrigliceridemia , Pancreatitis , Humanos , Calcio , Neutrófilos , Enfermedad Aguda , Estudios Retrospectivos , Hipertrigliceridemia/complicaciones , Apolipoproteínas , Apolipoproteínas A , Apolipoproteínas B
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