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1.
Neurogenetics ; 25(2): 131-139, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38460076

RESUMEN

Twin and family studies have established the genetic contribution to idiopathic generalized epilepsy (IGE). The genetic architecture of IGE is generally complex and heterogeneous, and the majority of the genetic burden in IGE remains unsolved. We hypothesize that gene-gene interactions contribute to the complex inheritance of IGE. CNTN2 (OMIM* 615,400) variants have been identified in cases with familial adult myoclonic epilepsy and other epilepsies. To explore the gene-gene interaction network in IGE, we took the CNTN2 gene as an example and investigated its co-occurrent genetic variants in IGE cases. We performed whole-exome sequencing in 114 unrelated IGE cases and 296 healthy controls. Variants were qualified with sequencing quality, minor allele frequency, in silico prediction, genetic phenotype, and recurrent case numbers. The STRING_TOP25 gene interaction network analysis was introduced with the bait gene CNTN2 (denoted as A). The gene-gene interaction pair mode was presumed to be A + c, A + d, A + e, with a leading gene A, or A + B + f, A + B + g, A + B + h, with a double-gene A + B, or other combinations. We compared the number of gene interaction pairs between the case and control groups. We identified three pairs in the case group, CNTN2 + PTPN18, CNTN2 + CNTN1 + ANK2 + ANK3 + SNTG2, and CNTN2 + PTPRZ1, while we did not discover any pairs in the control group. The number of gene interaction pairs in the case group was much more than in the control group (p = 0.021). Taking together the genetic bioinformatics, reported epilepsy cases, and statistical evidence in the study, we supposed CNTN2 as a candidate pathogenic gene for IGE. The gene interaction network analysis might help screen candidate genes for IGE or other complex genetic disorders.


Asunto(s)
Contactinas , Epilepsia Generalizada , Epistasis Genética , Redes Reguladoras de Genes , Predisposición Genética a la Enfermedad , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Adulto Joven , Estudios de Casos y Controles , Contactinas/genética , Epilepsia Generalizada/genética , Secuenciación del Exoma , Frecuencia de los Genes
2.
J Hum Genet ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38866925

RESUMEN

BACKGROUND: Intronic GAA repeat expansion ([GAA] ≥250) in FGF14 is associated with the late-onset neurodegenerative disorder, spinocerebellar ataxia 27B (SCA27B, GAA-FGF14 ataxia). We aim to determine the prevalence of the GAA repeat expansion in FGF14 in Chinese populations presenting late-onset cerebellar ataxia (LOCA) and evaluate the characteristics of tandem repeat inheritance, radiological features and sympathetic nerve involvement. METHODS: GAA-FGF14 repeat expansion was screened in an undiagnosed LOCA cohort (n = 664) and variations in repeat-length were analyzed in families of confirmed GAA-FGF14 ataxia patients. Brain magnetic resonance imaging (MRI) was used to evaluate the radiological feature in GAA-FGF14 ataxia patients. Clinical examinations and sympathetic skin response (SSR) recordings in GAA-FGF14 patients (n = 16) were used to quantify sympathetic nerve involvement. RESULTS: Two unrelated probands (2/664) were identified. Genetic screening for GAA-FGF14 repeat expansion was performed in 39 family members, 16 of whom were genetically diagnosed with GAA-FGF14 ataxia. Familial screening revealed expansion of GAA repeats in maternal transmissions, but contraction upon paternal transmission. Brain MRI showed slight to moderate cerebellar atrophy. SSR amplitude was lower in GAA-FGF14 patients in pre-symptomatic stage compared to healthy controls, and further decreased in the symptomatic stage. CONCLUSIONS: GAA-FGF14 ataxia was rare among Chinese LOCA cases. Parental gender appears to affect variability in GAA repeat number between generations. Reduced SSR amplitude is a prominent feature in GAA-FGF14 patients, even in the pre-symptomatic stage.

3.
Plant Cell ; 33(3): 457-474, 2021 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-33955483

RESUMEN

Communication between cellular compartments is vital for development and environmental adaptation. Signals emanating from organelles, so-called retrograde signals, coordinate nuclear gene expression with the developmental stage and/or the functional status of the organelle. Plastids (best known in their green photosynthesizing differentiated form, the chloroplasts) are the primary energy-producing compartment of plant cells, and the site for the biosynthesis of many metabolites, including fatty acids, amino acids, nucleotides, isoprenoids, tetrapyrroles, vitamins, and phytohormone precursors. Signals derived from plastids regulate the accumulation of a large set of nucleus-encoded proteins, many of which localize to plastids. A set of mutants defective in retrograde signaling (genomes uncoupled, or gun) was isolated over 25 years ago. While most GUN genes act in tetrapyrrole biosynthesis, resolving the molecular function of GUN1, the proposed integrator of multiple retrograde signals, has turned out to be particularly challenging. Based on its amino acid sequence, GUN1 was initially predicted to be a plastid-localized nucleic acid-binding protein. Only recently, mechanistic information on the function of GUN1 has been obtained, pointing to a role in plastid protein homeostasis. This review article summarizes our current understanding of GUN-related retrograde signaling and provides a critical appraisal of the various proposed roles for GUNs and their respective pathways.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Unión al ADN/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Plastidios/genética , Plastidios/metabolismo , Transducción de Señal/genética , Transducción de Señal/fisiología
4.
Artículo en Inglés | MEDLINE | ID: mdl-38619440

RESUMEN

BACKGROUND: Lupus erythematosus (LE) is a spectrum of autoimmune diseases. Due to the complexity of cutaneous LE (CLE), clinical skin image-based artificial intelligence is still experiencing difficulties in distinguishing subtypes of LE. OBJECTIVES: We aim to develop a multimodal deep learning system (MMDLS) for human-AI collaboration in diagnosis of LE subtypes. METHODS: This is a multi-centre study based on 25 institutions across China to assist in diagnosis of LE subtypes, other eight similar skin diseases and healthy subjects. In total, 446 cases with 800 clinical skin images, 3786 multicolor-immunohistochemistry (multi-IHC) images and clinical data were collected, and EfficientNet-B3 and ResNet-18 were utilized in this study. RESULTS: In the multi-classification task, the overall performance of MMDLS on 13 skin conditions is much higher than single or dual modals (Sen = 0.8288, Spe = 0.9852, Pre = 0.8518, AUC = 0.9844). Further, the MMDLS-based diagnostic-support help improves the accuracy of dermatologists from 66.88% ± 6.94% to 81.25% ± 4.23% (p = 0.0004). CONCLUSIONS: These results highlight the benefit of human-MMDLS collaborated framework in telemedicine by assisting dermatologists and rheumatologists in the differential diagnosis of LE subtypes and similar skin diseases.

5.
Sensors (Basel) ; 24(12)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38931572

RESUMEN

Atrial fibrillation (AF) is a common arrhythmia, and out-of-hospital, wearable, long-term electrocardiogram (ECG) monitoring can help with the early detection of AF. The presence of a motion artifact (MA) in ECG can significantly affect the characteristics of the ECG signal and hinder early detection of AF. Studies have shown that (a) using reference signals with a strong correlation with MAs in adaptive filtering (ADF) can eliminate MAs from the ECG, and (b) artificial intelligence (AI) algorithms can recognize AF when there is no presence of MAs. However, no literature has been reported on whether ADF can improve the accuracy of AI for recognizing AF in the presence of MAs. Therefore, this paper investigates the accuracy of AI recognition for AF when ECGs are artificially introduced with MAs and processed by ADF. In this study, 13 types of MA signals with different signal-to-noise ratios ranging from +8 dB to -16 dB were artificially added to the AF ECG dataset. Firstly, the accuracy of AF recognition using AI was obtained for a signal with MAs. Secondly, after removing the MAs by ADF, the signal was further identified using AI to obtain the accuracy of the AF recognition. We found that after undergoing ADF, the accuracy of AI recognition for AF improved under all MA intensities, with a maximum improvement of 60%.


Asunto(s)
Algoritmos , Artefactos , Inteligencia Artificial , Fibrilación Atrial , Electrocardiografía , Procesamiento de Señales Asistido por Computador , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Electrocardiografía/métodos , Humanos , Relación Señal-Ruido
6.
Molecules ; 29(11)2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38893550

RESUMEN

Transparent soil (TS) presents immense potential for root phenotyping due to its ability to facilitate high-resolution imaging. However, challenges related to transparency, mechanical properties, and cost hinder its development. Herein, we introduce super-transparent soil (s-TS) prepared via the droplet method using low acyl gellan gum and hydroxyethyl cellulose crosslinked with magnesium ions. The refractive index of the hydroxyethyl cellulose solution (1.345) closely aligns with that of water (1.333) and the low acyl gellan gum solution (1.340), thereby significantly enhancing the transmittance of hydrogel-based transparent soil. Optimal transmittance (98.45%) is achieved with polymer concentrations ranging from 0.8 to 1.6 wt.% and ion concentrations between 0.01 and 0.09 mol·L-1. After 60 days of plant cultivation, s-TS maintains a transmittance exceeding 89.5%, enabling the detailed visualization of root growth dynamics. Furthermore, s-TS exhibits remarkable mechanical properties, withstanding a maximum compressive stress of 477 kPa and supporting a maximum load-bearing depth of 186 cm. This innovative approach holds promising implications for advanced root phenotyping studies, fostering the investigation of root heterogeneity and the development of selective expression under controlled conditions.


Asunto(s)
Fenotipo , Raíces de Plantas , Suelo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/química , Suelo/química , Polisacáridos Bacterianos/química
7.
J Am Chem Soc ; 145(49): 26863-26870, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38048529

RESUMEN

Spin-state transition is a vital factor that dominates catalytic processes, but unveiling its mechanism still faces the great challenge of the lack of catalyst model systems. Herein, we propose that the {Fe-Pt} Hofmann clathrates, whose dynamic spin-state transition of metal centers can be chemically manipulated through iodine treatment, can serve as model systems in the spin-related structural-catalytic relationship study. Taking the photocatalytic synthesis of H2O2 as the basic catalytic reaction, when the spin state of Fe(II) in the clathrate is high spin (HS), sacrificial agents are indispensable to the photosynthesis of H2O2 because only the photocatalytic oxygen reduction reaction (ORR) occurs; when it is low spin (LS), both the ORR and water oxidation reaction (WOR) can take place, enabling a high H2O2 photosynthesis rate of 66 000 µM g-1 h-1 under visible-light irradiation. In situ characterizations combined with density functional theory calculations confirmed that, compared with the HS-state counterpart, the LS state can induce strong charge transfer between the LS Fe(II) and the iodide-coordinating Pt(IV) in the polymer and reduce the energy barriers for both the ORR and WOR processes, dominating the on-off switching upon the photosynthesis of H2O2 in O2-saturated water. What's more, the one-pot tandem reactions were conducted to utilize the synthesized H2O2 for transforming the low-value-added sodium alkenesulfonates into value-added bromohydrin products with decent conversion rates. This work provides a pioneering investigation into on-off switching the photocatalytic overall reaction through manipulating the metallic spin-state transition in spin-crossover systems.

8.
Neurogenetics ; 24(3): 161-169, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37022522

RESUMEN

Gene sub-region encoded protein domain is the basic unit for protein structure and function. The DMD gene is the largest coding gene in humans, with its phenotype relevant to idiopathic generalized epilepsy. We hypothesized variants clustered in sub-regions of idiopathic generalized epilepsy genes and investigated the relationship between the DMD gene and idiopathic generalized epilepsy. Whole exome sequencing was performed in 106 idiopathic generalized epilepsy individuals. DMD variants were filtered with variant type, allele frequency, in silico prediction, hemizygous or homozygous status in the population, inheritance mode, and domain location. Variants located at the sub-regions were selected by the subRVIS software. The pathogenicity of variants was evaluated by the American College of Medical Genetics and Genomics criteria. Articles on functional studies related to epilepsy for variants clustered protein domains were reviewed. In sub-regions of the DMD gene, two variants were identified in two unrelated cases with juvenile absence epilepsy or juvenile myoclonic epilepsy. The pathogenicity of both variants was uncertain significance. Allele frequency of both variants in probands with idiopathic generalized epilepsy reached statistical significance compared with the population (Fisher's test, p = 2.02 × 10-6, adjusted α = 4.52 × 10-6). The variants clustered in the spectrin domain of dystrophin, which binds to glycoprotein complexes and indirectly affects ion channels contributing to epileptogenesis. Gene sub-region analysis suggests a weak association between the DMD gene and idiopathic generalized epilepsy. Functional analysis of gene sub-region helps infer the pathogenesis of idiopathic generalized epilepsy.


Asunto(s)
Epilepsia Generalizada , Epilepsia , Humanos , Epilepsia Generalizada/genética , Frecuencia de los Genes , Fenotipo
9.
Stem Cells ; 40(2): 133-148, 2022 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-35257186

RESUMEN

The N-terminal caveolin-binding motif (CBM) in Na/K-ATPase (NKA) α1 subunit is essential for cell signaling and somitogenesis in animals. To further investigate the molecular mechanism, we have generated CBM mutant human-induced pluripotent stem cells (iPSCs) through CRISPR/Cas9 genome editing and examined their ability to differentiate into skeletal muscle (Skm) cells. Compared with the parental wild-type human iPSCs, the CBM mutant cells lost their ability of Skm differentiation, which was evidenced by the absence of spontaneous cell contraction, marker gene expression, and subcellular myofiber banding structures in the final differentiated induced Skm cells. Another NKA functional mutant, A420P, which lacks NKA/Src signaling function, did not produce a similar defect. Indeed, A420P mutant iPSCs retained intact pluripotency and ability of Skm differentiation. Mechanistically, the myogenic transcription factor MYOD was greatly suppressed by the CBM mutation. Overexpression of a mouse Myod cDNA through lentiviral delivery restored the CBM mutant cells' ability to differentiate into Skm. Upstream of MYOD, Wnt signaling was demonstrated from the TOPFlash assay to have a similar inhibition. This effect on Wnt activity was further confirmed functionally by defective induction of the presomitic mesoderm marker genes BRACHYURY (T) and MESOGENIN1 (MSGN1) by Wnt3a ligand or the GSK3 inhibitor/Wnt pathway activator CHIR. Further investigation through immunofluorescence imaging and cell fractionation revealed a shifted membrane localization of ß-catenin in CBM mutant iPSCs, revealing a novel molecular component of NKA-Wnt regulation. This study sheds light on a genetic regulation of myogenesis through the CBM of NKA and control of Wnt/ß-catenin signaling.


Asunto(s)
Glucógeno Sintasa Quinasa 3 , beta Catenina , Animales , Caveolina 1/genética , Caveolina 1/metabolismo , Caveolina 1/farmacología , Diferenciación Celular , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3/farmacología , Ratones , Desarrollo de Músculos/genética , ATPasa Intercambiadora de Sodio-Potasio/genética , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Vía de Señalización Wnt , beta Catenina/metabolismo
10.
Adv Appl Microbiol ; 122: 127-150, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37085192

RESUMEN

As a semi-essential amino acid, l-arginine (l-Arg) plays an important role in food, health care, and medical treatment. At present, the main method of producing l-Arg is the use of microbial fermentation. Therefore, the selection and breeding of high-efficiency microbial strains is the top priority. To continuously improve the l-Arg production performance of the strains, a series of metabolic engineering strategies have been tried to transform the strains. The production of l-Arg by metabolically engineered Corynebacterium glutamicum (C. glutamicum) reached a relatively high level. Escherichia coli (E. coli), as a strain with great potential for l-Arg production, also has a large number of research strategies aimed at screening effective E. coli for producing l-Arg. E. coli also has a number of advantages over C. glutamicum in producing l-Arg. Therefore, it is of great significance to screen out excellent and stable E. coli to produce l-Arg. Here, based on recent research results, we review the metabolic pathways of l-Arg production in E. coli, the research progress of l-Arg production in E. coli, and various regulatory strategies implemented in E. coli.


Asunto(s)
Corynebacterium glutamicum , Proteínas de Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Ingeniería Metabólica/métodos , Arginina/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Fermentación
11.
Eur Radiol ; 33(3): 2160-2170, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36222864

RESUMEN

OBJECTIVES: To construct and validate a contrast-enhanced computed tomography (CECT)-based radiomics nomogram to predict Ki-67 expression level in head and neck squamous cell carcinoma (HNSCC). METHODS: A total of 217 patients with HNSCC who underwent CECT scans and immunohistochemical examination of their Ki-67 index were enrolled in this study. The patients were divided into a training set (n = 140; Ki-67: ≥ 50% [n = 72] and < 50% [n = 68]) and an external test set (n = 77; Ki-67: ≥ 50% [n = 38] and < 50% [n = 39]). The least absolute shrinkage and selection operator method was used to select key features for a CECT-image-based radiomics signature and a radiomics score (Rad-score) was calculated. A clinical model was established using clinical data and CT findings. The independent clinical factors and Rad-score were then combined to construct a radiomics nomogram. The performance characteristics of the Rad-score, clinical model, and nomogram were assessed using ROCs and decision curve analysis. RESULTS: Twenty features were finally selected to construct the Rad-score. The radiomics nomogram incorporating the Rad-score, low histological grade, and lymphatic spread showed higher predictive value for the Ki-67 index (≥ 50% vs. < 50%) than the clinical model on both the training (AUC, 0.919 vs. 0.648, p < 0.001) and test (AUC, 0.832 vs. 0.685, p = 0.030) sets. Decision curve analysis demonstrated that the radiomics nomogram was more clinically useful than the clinical model. CONCLUSIONS: A CECT-based radiomics nomogram was constructed to predict the expression of Ki-67 in HNSCC. This model showed favorable predictive efficacy and might be useful for prognostic evaluation and clinical decision-making in patients with HNSCC. KEY POINTS: • Accurate pre-treatment prediction of Ki-67 index in HNSCC is crucial. • A CECT-based radiomics nomogram showed favorable predictive efficacy in estimation of Ki-67 expression status in HNSCC patients.


Asunto(s)
Neoplasias de Cabeza y Cuello , Nomogramas , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello , Antígeno Ki-67 , Tomografía Computarizada por Rayos X/métodos , Neoplasias de Cabeza y Cuello/diagnóstico por imagen
12.
Hepatobiliary Pancreat Dis Int ; 22(4): 358-365, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35370090

RESUMEN

BACKGROUND: Significant portal hypertension (SPH) is a relative contraindication for patients with resectable hepatocellular carcinoma (HCC). However, increasing evidence indicates that liver resection is feasible for HCC patients with SPH. METHODS: HCC patients with cirrhosis who underwent laparoscopic liver resection (LLR) in two centers from January 2013 to April 2018 were included. Surgical and survival outcomes were analyzed to explore potential prognostic factors. Propensity score matching (PSM) analysis was performed to minimize bias. RESULTS: A total of 165 patients were divided into two groups based on the presence (SPH, n = 76) or absence (non-SPH, n = 89) of SPH. Patients in the SPH group had longer operative time, more blood loss, and more advanced TNM stage than patients in the non-SPH group (P < 0.05). However, there were no significant differences in the postoperative 90-day mortality rate (n = 0), overall postoperative complications (47.4% vs. 41.6%, P = 0.455), Clavien-Dindo classification (P = 0.347), conversion to open surgery (9.2% vs. 6.7%, P = 0.557), or length of hospitalization (16 vs. 15 days, P = 0.203) between the SPH and non-SPH groups before PSM. Similar results were obtained after PSM. The 1-, 3-, and 5-year overall survival (OS) and recurrence-free survival rates in the SPH group were not significantly different from those in the non-SPH group both before and after PSM (log-rank P > 0.05). After PSM, alpha-fetoprotein (AFP) ≥ 400 µg/L [hazard ratio (HR) = 4.71, 95% confidence interval (CI): 2.69-8.25], ascites (HR = 2.18, 95% CI: 1.30-3.66), American Society of Anesthesiologists (ASA) classification (III vs. II) (HR = 2.13, 95% CI: 1.11-4.07) and tumor diameter > 5 cm (HR = 3.91, 95% CI: 2.02-7.56) independently predicted worse OS. CONCLUSIONS: LLR for patients with HCC complicated with SPH appears feasible at the price of increasing operative time and blood loss. AFP, ascites, ASA classification and tumor diameter may predict the prognosis of HCC complicated with SPH after LLR.


Asunto(s)
Carcinoma Hepatocelular , Hipertensión Portal , Laparoscopía , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/cirugía , alfa-Fetoproteínas , Ascitis , Puntaje de Propensión , Estudios Retrospectivos , Hepatectomía/métodos , Análisis de Supervivencia , Hipertensión Portal/complicaciones , Hipertensión Portal/diagnóstico , Laparoscopía/efectos adversos , Laparoscopía/métodos , Complicaciones Posoperatorias/cirugía , Tiempo de Internación
13.
Inorg Chem ; 61(4): 2141-2153, 2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35049278

RESUMEN

The present work is part of our ongoing quest for developing functional inorganic complexes using unorthodox pyridyl-pyrazolyl-based ligands. Accordingly, we report herein the synthesis, characterization, and luminescence and magnetic properties of four 3d-4f mixed-metal complexes with a general core of Ln2Zn6 (Ln = Dy, Gd, Tb, and Eu). In stark contrast to the popular wisdom of using a compartmental ligand with separate islands of hard and soft coordinating sites for selective coordination, we have vindicated our approach of using a ligand with overcrowded N-coordinating sites that show equal efficiency with both 4f and 3d metals toward multinuclear cage-cluster formation. The encouraging red and green photolumiscent features of noncytotoxic Eu2Zn6 and Tb2Zn6 complexes along with their existence in nanoscale dimension have been exploited with live-cell confocal microscopy imaging of human breast adenocarcinoma (MCF7) cells. The magnetic features of the Dy2Zn6 complex confirm the single-molecule-magnet behavior with befitting frequency- and temperature-dependent out-of-phase signals along with an Ueff value of ∼5 K and a relaxation time of 8.52 × 10-6 s. The Gd2Zn6 complex, on the other hand, shows cryogenic magnetic refrigeration with an entropy change of 11.25 J kg-1 K-1 at a magnetic field of 7 T and at 2 K. Another important aspect of this work reflects the excellent agreement between the experimental results and theoretical calculations. The theoretical studies carried out using the broken-symmetry density functional theory, ORCA suite of programs, and MOLCAS calculations using the complete-active-space self-consistent-field method show an excellent synergism with the experimentally measured magnetic and spectroscopic data.

14.
Inorg Chem ; 61(24): 9047-9054, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35678748

RESUMEN

Linkage isomers involving changes in the bonding mode of ambidentate ligands have potential applications in data storage, molecular machines, and motors. However, the observation of the cyanide-linkage-isomerism-induced spin change (CLIISC) effect characterized by single-crystal X-ray diffraction remains a considerable challenge. Meanwhile, the high-spin and low-spin states can be reversibly switched in spin-crossover (SCO) compounds, which provide the potential for applications to data storage, switches, and sensors. Here, a new perovskite-type SCO framework (PPN)[Fe{Ag(CN)2}3] (PPN+ = bis(trisphenylphosphine)iminium cation) is synthesized, which displays the unprecedented aging and temperature dependences of hysteretic multistep SCO behaviors near room temperature. Moreover, the thermal-induced cyanide linkage isomerization from FeII-N≡C-AgI to FeII-C≡N-AgI is revealed by single-crystal X-ray diffraction, Raman, and Mössbauer spectra, which is associated with a transition from the mixed spin state to the low-spin state and a dramatic volume shrinkage. Considering the wide use of cyanogen in magnetic systems, the association of CLIISC and SCO opens a new dimension to modulate the spin state and realize a colossal negative thermal expansion.

15.
Inorg Chem ; 61(16): 6017-6025, 2022 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35420419

RESUMEN

Magnetic bistability in single-molecule magnets (SMMs) is a potential basis for new types of nanoscale information storage material. The standard model for thermally activated relaxation of the magnetization in SMMs is based on the occurrence of a single Orbach process. Here, we show that incorporating a phosphorus atom into the framework of the dysprosium metallocene [(CpiPr5)Dy(CpPEt4)]+[B(C6F5)4]- (CpiPr5 is penta-isopropylcyclopentadienyl, CpPEt4 is tetraethylphospholyl) leads to the occurrence of two distinct high-temperature Orbach processes, with energy barriers of 1410(10) and 747(7) cm-1, respectively. These barriers provide experimental evidence for two different spin-phonon coupling regimes, which we explain with the aid of ab initio calculations. The strong and highly axial crystal field in this SMM also allows magnetic hysteresis to be observed up to 70 K, using a scan rate of 25 Oe s-1. In characterizing this SMM, we show that a conventional Debye model and consideration of rotational contributions to the spin-phonon interaction are insufficient to explain the observed phenomena.

16.
Artículo en Inglés | MEDLINE | ID: mdl-35809333

RESUMEN

Matrix metalloproteinase-9 (MMP-9) is a gelatinase, which is a member of the MMPs family. We know that MMP-9 is not only an important gelatinase to regulate the extracellular matrix balance, but also one of the most closely related proteases to the pathogenesis of intracranial aneurysm. The purpose of this study is to investigate the relationship between MMP-9 gene polymorphism and intracranial aneurysm. In this paper, 98 patients who were admitted to a hospital from 2018 to 2019 were selected as the experimental group and the control group according to the relevant standards of intracranial aneurysms. The MMP-9 positive and MMP-9 absorbance values between the two groups were compared, so as to determine the concentration of MMP-9 between the two groups. In addition, the gene distribution and gene frequency analysis of the C-1562T promoter region of MMP-9 were carried out. The results showed that in the control group, the gene distribution frequency of CC type was 67% that of CT type was 31% that of TT type was 2%, that of the experimental group was 52%, and that of CT type was 44%. The results showed that there was a correlation between MMP-9 gene polymorphism and intracranial aneurysm.


Asunto(s)
Aneurisma Intracraneal , Metaloproteinasa 9 de la Matriz , Gelatinasas/genética , Frecuencia de los Genes/genética , Humanos , Aneurisma Intracraneal/genética , Metaloproteinasa 9 de la Matriz/genética , Polimorfismo Genético
17.
Ecotoxicol Environ Saf ; 237: 113533, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35453025

RESUMEN

Cadmium (Cd) is a dispensable element that can be absorbed by crops, posing a threat to human health through the food chains. Melatonin (MT), as a plant growth regulator, has been used to alleviate Cd toxicity in many plant species; however, the underlying molecular mechanisms responsible for Cd toxicity in wheat are still poorly understood. In this study, the suitable exogenous MT concentration (50 µM) was screened to mitigate Cd toxicity of wheat plants by increasing the plant height, root length, fresh or dry weight and chlorophyll content, or decreasing the malondialdehyde (MDA) content. In addition, MT application significantly increased ascorbic acid (ASA) and glutathione (GSH) content by reducing ROS production, especially in roots, further decreasing Cd content in fraction of organelles. Moreover, the expression levels of ASA-GSH synthesis genes, APX, GR, and GST were significantly increased by 171.5%, 465.2%, and 256.8% in roots, respectively, whereas GSH, DHAR, or MDHAR were significantly decreased by 48.5%, 54.3%, or 60.0% in roots under MT + Cd stress. However, the expression levels of Cd-induced metal transporter genes TaNramp1, TaNramp5, TaHMA2, TaHMA3, and TaLCT1 were significantly decreased by 53.7%, 50.1%, 86.5%, 87.2%, and 94.5% in roots under MT + Cd stress compared with alone Cd treatment, respectively. In conclusion, our results suggesting that MT alleviate Cd toxicity in wheat by enhancing ASA-GSH metabolism, suppressing Cd transporter gene expression, and regulating Cd uptake and translocation in wheat plants.


Asunto(s)
Ácido Ascórbico , Melatonina , Antioxidantes/metabolismo , Antioxidantes/farmacología , Ácido Ascórbico/metabolismo , Ácido Ascórbico/farmacología , Cadmio/metabolismo , Cadmio/toxicidad , Glutatión/metabolismo , Humanos , Melatonina/metabolismo , Melatonina/farmacología , Estrés Oxidativo , Raíces de Plantas/metabolismo , Plantones/metabolismo , Triticum/metabolismo
18.
Ecotoxicol Environ Saf ; 233: 113313, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35182801

RESUMEN

BACKGROUND: A few studies have reported phthalate exposure as a risk factor for depressive symptoms, but the results have been inconsistent. Whether chronic inflammation mediates the relationship between phthalates (PAEs) and depressive symptoms remains unclear. In this study, we establish mediating models of inflammatory factors and explore the mediating role of chronic inflammation in the association between PAEs exposure and depressive symptoms. METHODS: The sample included 989 participants from the Study on Health and Environment of the Elderly in Lu'an City, Anhui Province. Geriatric depression scale (GDS-30) was used to screen depressive symptoms of the elderly. The levels of seven kinds of PAEs in urine samples and four inflammatory factors in serum of the elderly were measured. To establish the mediating effect of inflammatory factors to explore the potential effect of PAEs exposure on the increased odds of depressive symptoms. RESULTS: Adjusted for multiple variables, the highest tertiles of Mono (2-ethylhexyl) phthalate (MEHP) (95%CI = 1.051-2.112), Mono benzyl phthalate (MBzP) (95%CI = 1.016-2.082) and Mono butyl phthalate (MBP) (95%CI = 1.102-2.262) were positively correlated with depressive symptoms. The mediating effect of IL-6 and generalized inflammation factor between MEHP exposure and depressive symptoms were 15.96% (95%CI=0.0288-0.1971) and 14.25% (95%CI = 0.0167-0.1899). CONCLUSIONS: High levels of MEHP, MBzP and MBP increased the odds of depressive symptoms in the elderly, and chronic inflammation had a partial mediating effect on the increased odds of depressive symptoms due to MEHP exposure.


Asunto(s)
Contaminantes Ambientales , Ácidos Ftálicos , Anciano , Depresión/inducido químicamente , Dibutil Ftalato , Exposición a Riesgos Ambientales/efectos adversos , Contaminantes Ambientales/toxicidad , Contaminantes Ambientales/orina , Humanos , Inflamación/inducido químicamente , Ácidos Ftálicos/toxicidad , Ácidos Ftálicos/orina
19.
Angew Chem Int Ed Engl ; 61(31): e202206749, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35599428

RESUMEN

The escalating contamination by per- and polyfluoroalkyl substances (PFAS) has become an urgent issue in recent years, and the structural diversity of PFAS is the major challenge for effective pollution control. Herein, we take the intrinsic advantages of squaramide and prepare a new two-dimensional covalent organic framework (FSQ-1) that exhibits broad-spectrum PFAS affinity. The tailor-made linker forges hydrogen-bond donors, hydrogen-bond acceptors, and fluorophilic segments into one framework. The obtained material exhibits multipoint and multitype affinity to PFAS with different structures, by which high-efficient and broad-spectrum removal of various PFAS can be simultaneously achieved. Notably, the thermodynamic profiles provided by isothermal titration calorimetry (ITC) experiments further illustrate the underlying mechanism of the broad-spectrum affinity. FSQ-1 can also be applied for efficient PFAS extraction in trace-level PFAS analysis.


Asunto(s)
Contaminantes Ambientales , Fluorocarburos , Estructuras Metalorgánicas , Contaminantes Químicos del Agua , Contaminantes Ambientales/análisis , Fluorocarburos/química , Hidrógeno , Quinina/análogos & derivados , Contaminantes Químicos del Agua/análisis
20.
Pak J Pharm Sci ; 35(4): 1037-1041, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36008900

RESUMEN

The current study aimed to establish simple and quick quality evaluation method of Chishao based on QAMS. Oxypaeoniflorin is used as a marker in the Chishao root. Based on it, the content of other components could be obtained by establishing the mathematical relationship. UPLC method was used to collect data, and the detection wavelengths were 230nm (benzoic acid, paeoniflorin), 263nm (hydroxy paeoniflorin) 274nm (gallic acid, paeoniflorin, catechin), respectively. The stationary phase was an Agilent ZORBAX SB-C18 and the mobile phase was acetonitrile -0.1% formic acid-water. The gradient elution method was adopted at the certain flow rate (0.3 mL/min). The column temperature set 40oC, and the injection volume was 1µL. Multiple reaction monitoring mode was selected for data collection. The linear ranges of benzoic acid, paeoniflorin, hydroxy-paeoniflorin, gallic acid, catechin and paeoniflorinhad good linearity (r ≥0.9995). The UPLC method was established to determine the content of paeoniflorin, benzoic acid, catechin, gallic acid, paeoniflorin, andhydroxy-paeoniflorin in Radix Paeoniae Rubra. In the current study, the method for the chemical components in Radix Paeoniae Rubra to provide the evaluation basis of medicinal effects.


Asunto(s)
Catequina , Medicamentos Herbarios Chinos , Paeonia , Ácido Benzoico , Hidrocarburos Aromáticos con Puentes , Cromatografía Líquida de Alta Presión/métodos , Ácido Gálico , Monoterpenos , Paeonia/química , Caracoles
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