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1.
Nature ; 632(8026): 775-781, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39169248

RESUMEN

Superconductivity involving finite-momentum pairing1 can lead to spatial-gap and pair-density modulations, as well as Bogoliubov Fermi states within the superconducting gap. However, the experimental realization of their intertwined relations has been challenging. Here we detect chiral kagome superconductivity modulations with residual Fermi arcs in KV3Sb5 and CsV3Sb5 using normal and Josephson scanning tunnelling microscopy down to 30 millikelvin with a resolved electronic energy difference at the microelectronvolt level. We observe a U-shaped superconducting gap with flat residual in-gap states. This gap shows chiral 2a × 2a spatial modulations with magnetic-field-tunable chirality, which align with the chiral 2a × 2a pair-density modulations observed through Josephson tunnelling. These findings demonstrate a chiral pair density wave (PDW) that breaks time-reversal symmetry. Quasiparticle interference imaging of the in-gap zero-energy states reveals segmented arcs, with high-temperature data linking them to parts of the reconstructed vanadium d-orbital states within the charge order. The detected residual Fermi arcs can be explained by the partial suppression of these d-orbital states through an interorbital 2a × 2a PDW and thus serve as candidate Bogoliubov Fermi states. In addition, we differentiate the observed PDW order from impurity-induced gap modulations. Our observations not only uncover a chiral PDW order with orbital selectivity but also show the fundamental space-momentum correspondence inherent in finite-momentum-paired superconductivity.

2.
Circulation ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38841852

RESUMEN

BACKGROUND: Dilated cardiomyopathy is characterized by left ventricular dilation and continuous systolic dysfunction. Mitochondrial impairment is critical in dilated cardiomyopathy; however, the underlying mechanisms remain unclear. Here, we explored the cardioprotective role of a heart-enriched long noncoding RNA, the dilated cardiomyopathy repressive transcript (DCRT), in maintaining mitochondrial function. METHODS: The DCRT knockout (DCRT-/-) mice and DCRT knockout cells were developed using CRISPR-Cas9 technology. Cardiac-specific DCRT transgenic mice were generated using α-myosin heavy chain promoter. Chromatin coimmunoprecipitation, RNA immunoprecipitation, Western blot, and isoform sequencing were performed to investigate the underlying mechanisms. RESULTS: We found that the long noncoding RNA DCRT was highly enriched in the normal heart tissues and that its expression was significantly downregulated in the myocardium of patients with dilated cardiomyopathy. DCRT-/- mice spontaneously developed cardiac dysfunction and enlargement with mitochondrial impairment. DCRT transgene or overexpression with the recombinant adeno-associated virus system in mice attenuated cardiac dysfunction induced by transverse aortic constriction treatment. Mechanistically, DCRT inhibited the third exon skipping of NDUFS2 (NADH dehydrogenase ubiquinone iron-sulfur protein 2) by directly binding to PTBP1 (polypyrimidine tract binding protein 1) in the nucleus of cardiomyocytes. Skipping of the third exon of NDUFS2 induced mitochondrial dysfunction by competitively inhibiting mitochondrial complex I activity and binding to PRDX5 (peroxiredoxin 5) and suppressing its antioxidant activity. Furthermore, coenzyme Q10 partially alleviated mitochondrial dysfunction in cardiomyocytes caused by DCRT reduction. CONCLUSIONS: Our study revealed that the loss of DCRT contributed to PTBP1-mediated exon skipping of NDUFS2, thereby inducing cardiac mitochondrial dysfunction during dilated cardiomyopathy development, which could be partially treated with coenzyme Q10 supplementation.

3.
Nano Lett ; 24(33): 10040-10046, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39133069

RESUMEN

Quantum interference is a natural consequence of wave-particle duality in quantum mechanics, and is widely observed at the atomic scale. One interesting manifestation of quantum interference is coherent population trapping (CPT), first proposed in three-level driven atomic systems and observed in quantum optical experiments. Here, we demonstrate CPT in a gate-defined semiconductor double quantum dot (DQD), with some unique twists as compared to the atomic systems. Specifically, we observe CPT in both driven and nondriven situations. We further show that CPT in a driven DQD could be used to generate adiabatic state transfer. Moreover, our experiment reveals a nontrivial modulation to the CPT caused by the longitudinal driving field, yielding an odd-even effect and a tunable CPT. Our results broaden the field of CPT, and open up the possibility of quantum simulation and quantum computation based on adiabatic passage in quantum dot systems.

4.
BMC Genomics ; 25(1): 379, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38632516

RESUMEN

BACKGROUND: Tumor cells exhibit a heightened susceptibility to lysosomal-dependent cell death (LCD) compared to normal cells. However, the role of LCD-related genes (LCD-RGs) in Osteosarcoma (OS) remains unelucidated. This study aimed to elucidate the role of LCD-RGs and their mechanisms in OS using several existing OS related datasets, including TCGA-OS, GSE16088, GSE14359, GSE21257 and GSE162454. RESULTS: Analysis identified a total of 8,629 DEGs1, 2,777 DEGs2 and 21 intersection genes. Importantly, two biomarkers (ATP6V0D1 and HDAC6) linked to OS prognosis were identified to establish the prognostic model. Significant differences in risk scores for OS survival were observed between high and low-risk cohorts. Additionally, scores of dendritic cells (DC), immature DCs and γδT cells differed significantly between the two risk cohorts. Cell annotations from GSE162454 encompassed eight types (myeloid cells, osteoblastic OS cells and plasma cells). ATP6V0D1 was found to be significantly over-expressed in myeloid cells and osteoclasts, while HDAC6 was under-expressed across all cell types. Moreover, single-cell trajectory mapping revealed that myeloid cells and osteoclasts differentiated first, underscoring their pivotal role in patients with OS. Furthermore, ATP6V0D1 expression progressively decreased with time. CONCLUSIONS: A new prognostic model for OS, associated with LCD-RGs, was developed and validated, offering a fresh perspective for exploring the association between LCD and OS.


Asunto(s)
Neoplasias Óseas , Osteosarcoma , Humanos , Pronóstico , Análisis de Secuencia de ARN , Muerte Celular , Lisosomas , ARN
5.
BMC Genomics ; 25(1): 328, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38566015

RESUMEN

BACKGROUND: Whole-genome duplication and long terminal repeat retrotransposons (LTR-RTs) amplification in organisms are essential factors that affect speciation, local adaptation, and diversification of organisms. Understanding the karyotype projection and LTR-RTs amplification could contribute to untangling evolutionary history. This study compared the karyotype and LTR-RTs evolution in the genomes of eight oaks, a dominant lineage in Northern Hemisphere forests. RESULTS: Karyotype projections showed that chromosomal evolution was relatively conservative in oaks, especially on chromosomes 1 and 7. Modern oak chromosomes formed through multiple fusions, fissions, and rearrangements after an ancestral triplication event. Species-specific chromosomal rearrangements revealed fragments preserved through natural selection and adaptive evolution. A total of 441,449 full-length LTR-RTs were identified from eight oak genomes, and the number of LTR-RTs for oaks from section Cyclobalanopsis was larger than in other sections. Recent amplification of the species-specific LTR-RTs lineages resulted in significant variation in the abundance and composition of LTR-RTs among oaks. The LTR-RTs insertion suppresses gene expression, and the suppressed intensity in gene regions was larger than in promoter regions. Some centromere and rearrangement regions indicated high-density peaks of LTR/Copia and LTR/Gypsy. Different centromeric regional repeat units (32, 78, 79 bp) were detected on different Q. glauca chromosomes. CONCLUSION: Chromosome fusions and arm exchanges contribute to the formation of oak karyotypes. The composition and abundance of LTR-RTs are affected by its recent amplification. LTR-RTs random retrotransposition suppresses gene expression and is enriched in centromere and chromosomal rearrangement regions. This study provides novel insights into the evolutionary history of oak karyotypes and the organization, amplification, and function of LTR-RTs.


Asunto(s)
Quercus , Retroelementos , Quercus/genética , Genoma de Planta , Cariotipo , Secuencias Repetidas Terminales/genética , Evolución Molecular , Filogenia
6.
BMC Plant Biol ; 24(1): 168, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438905

RESUMEN

BACKGROUND: Forests are essential for maintaining species diversity, stabilizing local and global climate, and providing ecosystem services. Exploring the impact of paleogeographic events and climate change on the genetic structure and distribution dynamics of forest keystone species could help predict responses to future climate change. In this study, we combined an ensemble species distribution model (eSDM) and multilocus phylogeography to investigate the spatial genetic patterns and distribution change of Quercus glauca Thunb, a keystone of East Asian subtropical evergreen broad-leaved forest. RESULTS: A total of 781 samples were collected from 77 populations, largely covering the natural distribution of Q. glauca. The eSDM showed that the suitable habitat experienced a significant expansion after the last glacial maximum (LGM) but will recede in the future under a general climate warming scenario. The distribution centroid will migrate toward the northeast as the climate warms. Using nuclear SSR data, two distinct lineages split between east and west were detected. Within-group genetic differentiation was higher in the West than in the East. Based on the identified 58 haplotypes, no clear phylogeographic structure was found. Populations in the Nanling Mountains, Wuyi Mountains, and the southwest region were found to have high genetic diversity. CONCLUSIONS: A significant negative correlation between habitat stability and heterozygosity might be explained by the mixing of different lineages in the expansion region after LGM and/or hybridization between Q. glauca and closely related species. The Nanling Mountains may be important for organisms as a dispersal corridor in the west-east direction and as a refugium during the glacial period. This study provided new insights into spatial genetic patterns and distribution dynamics of Q. glauca.


Asunto(s)
Ecosistema , Quercus , Quercus/genética , Filogeografía , Bosques , Cambio Climático
7.
Small ; : e2402925, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38874069

RESUMEN

Aqueous Zn metal batteries are attracting tremendous interest as promising energy storage systems due to their intrinsic safety and cost-effectiveness. Nevertheless, the reversibility of Zn metal anodes (ZMAs) is hindered by water-induced parasitic reactions and dendrite growth. Herein, a novel hydrated eutectic electrolyte (HEE) consisting of Zn(BF4)2·xH2O and sulfolane (SL) is developed to prevent the side reactions and achieve the outstanding cyclability of ZMAs. The strong coordination between Zn2+ and SL triggers the eutectic feature, enabling the low-temperature availability of HEEs. The restriction of BF4 - hydrolysis in the eutectic system can realize favorable compatibility between Zn(BF4)2-based electrolyte and ZMAs. Besides, the newly-established solvation structure with the participation of SL, H2O, and BF4 -, can induce in situ formation of desirable SEI with gradient structure consisting of B,O-rich species, ZnS, and ZnF2, to offer satisfactory protection toward ZMAs. Consequently, the HEE allows the Zn||Zn symmetric cell to cycle over 1650 h at 2 mA cm-2 and 1 mA h cm-2. Moreover, the Zn||NH4V4O10 full batteries can deliver a prolonged lifespan for 1000 cycles with a high capacity retention of 83.4%. This work represents a feasible approach toward the elaborate design of advanced electrolyte systems for next-generation batteries.

8.
J Synchrotron Radiat ; 31(Pt 2): 385-393, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300130

RESUMEN

As a representative of the fourth-generation light sources, the High Energy Photon Source (HEPS) in Beijing, China, utilizes a multi-bend achromat lattice to obtain an approximately 100 times emittance reduction compared with third-generation light sources. New technologies bring new challenges to operate the storage ring. In order to meet the beam commissioning requirements of HEPS, a new framework for the development of high-level applications (HLAs) has been created. The key part of the new framework is a dual-layer physical module to facilitate the seamless fusion of physical simulation models with the real machine, allowing for fast switching between different simulation models to accommodate the various simulation scenarios. As a framework designed for development of physical applications, all variables are based on physical quantities. This allows physicists to analytically assess measurement parameters and optimize machine parameters in a more intuitive manner. To enhance both extensibility and adaptability, a modular design strategy is utilized, partitioning the entire framework into discrete modules in alignment with the requirements of HLA development. This strategy not only facilitates the independent development of each module but also minimizes inter-module coupling, thereby simplifying the maintenance and expansion of the entire framework. To simplify the development complexity, the design of the new framework is implemented using Python and is called Python-based Accelerator Physics Application Set (Pyapas). Taking advantage of Python's flexibility and robust library support, we are able to develop and iterate quickly, while also allowing for seamless integration with other scientific computing applications. HLAs for both the HEPS linac and booster have been successfully developed. During the beam commissioning process at the linac, Pyapas's ease of use and reliability have significantly reduced the time required for the beam commissioning operators. As a development framework for HLA designed for the new-generation light sources, Pyapas has the versatility to be employed with HEPS, as well as with other comparable light sources, due to its adaptability.

9.
J Med Virol ; 96(3): e29531, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38515377

RESUMEN

The Nucleocapsid Protein (NP) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is not only the core structural protein required for viral packaging, but also participates in the regulation of viral replication, and its post-translational modifications such as phosphorylation have been shown to be an important strategy for regulating virus proliferation. Our previous work identified NP could be ubiquitinated, as confirmed by two independent studies. But the function of NP ubiquitination is currently unknown. In this study, we first pinpointed TRIM6 as the E3 ubiquitin ligase responsible for NP ubiquitination, binding to NP's CTD via its RING and B-box-CCD domains. TRIM6 promotes the K29-typed polyubiquitination of NP at K102, K347, and K361 residues, increasing its binding to viral genomic RNA. Consistently, functional experiments such as the use of the reverse genetic tool trVLP model and gene knockout of TRIM6 further confirmed that blocking the ubiquitination of NP by TRIM6 significantly inhibited the proliferation of SARS-CoV-2. Notably, the NP of coronavirus is relatively conserved, and the NP of SARS-CoV can also be ubiquitinated by TRIM6, indicating that NP could be a broad-spectrum anti-coronavirus target. These findings shed light on the intricate interaction between SARS-CoV-2 and the host, potentially opening new opportunities for COVID-19 therapeutic development.


Asunto(s)
COVID-19 , Genoma Viral , SARS-CoV-2 , Ubiquitina-Proteína Ligasas , Humanos , Proliferación Celular , COVID-19/genética , COVID-19/virología , Proteínas de la Nucleocápside/genética , ARN Viral/genética , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteínas de Motivos Tripartitos/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Proteínas de la Nucleocápside de Coronavirus/genética , Proteínas de la Nucleocápside de Coronavirus/metabolismo
10.
Eur J Clin Invest ; 54(9): e14233, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38666585

RESUMEN

BACKGROUND: Studies on the predictive ability of disease-specific health quality of life (QoL) in patients with heart failure (HF) have produced conflicting results. To address these gaps in knowledge, we conducted a meta-analysis to evaluate the predictive value of QoL measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ) in patients with HF. MATERIALS AND METHODS: We searched PubMed, and Embase databases to identify studies investigating the predictive utility of baseline QoL measured by the KCCQ in HF patients. The outcome measures were all-cause mortality and HF hospitalisation. The predictive value of QoL was expressed by pooling the adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the bottom versus the top category of KCCQ score or for per 10-point KCCQ score decrease. RESULTS: Twelve studies reporting on 11 articles with a total of 34,927 HF patients were identified. Comparison of the bottom with the top KCCQ score, the pooled adjusted HR was 2.34 (95% CI 2.10-2.60) and 2.53 (95% CI 2.23-2.88) for all-cause mortality and HF hospitalisation, respectively. Additionally, a 10-point decrease in KCCQ score was associated with a 12% (95% CI 7%-16%) increased risk of all-cause mortality and a 14% (95% CI 13%-15%) increased risk of HF hospitalisation. CONCLUSIONS: Poor health-related QoL as determined by the lower KCCQ score, was associated with an increased risk of all-cause mortality and HF hospitalisation in patients with HF. Measuring disease-specific health-related QoL using the KCCQ score may provide valuable predictive information for HF patients.


Asunto(s)
Insuficiencia Cardíaca , Hospitalización , Calidad de Vida , Humanos , Hospitalización/estadística & datos numéricos , Encuestas y Cuestionarios , Valor Predictivo de las Pruebas , Causas de Muerte
11.
Phys Rev Lett ; 132(3): 036601, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38307042

RESUMEN

Implementing topological superconductivity (TSC) and Majorana states (MSs) is one of the most significant and challenging tasks in both fundamental physics and topological quantum computations. In this work, taking the obstructed atomic insulator (OAI) Nb_{3}Br_{8}, s-wave superconductor (SC) NbSe_{2}, and ferromagnetic insulator (FMI) CrI_{3} as an example, we propose a new setup to realize the 2D chiral TSC and MSs in the SC/OAI/FMI heterostructure, which could avoid the subband problem effectively and has the advantage of huge Rashba spin-orbit coupling. As a result, the TSC phase can be stabilized in a wide region of chemical potential and Zeeman splitting, and four distinct TSC phases with superconducting Chern number N=-1,-2,-3, 3 can be achieved. Moreover, a 2D Bogoliubov-de Gennes Hamiltonian based on the triangular lattice of obstructed Wannier charge centers, combined with the s-wave superconductivity paring and Zeeman splitting, is constructed to understand the whole topological phase diagram analytically. These results expand the application of OAIs and pave a new way to realize the TSC and MSs with unique advantages.

12.
BMC Cancer ; 24(1): 558, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702621

RESUMEN

BACKGROUND: Portal hypertension (PHT) has been proven to be closely related to the development of hepatocellular carcinoma (HCC). Whether PHT before liver transplantation (LT) will affect the recurrence of HCC is not clear. METHODS: 110 patients with depressurization of the portal vein (DPV) operations (Transjugular Intrahepatic Portosystemic Shunt-TIPS, surgical portosystemic shunt or/and splenectomy) before LT from a HCC LT cohort, matched with 330 preoperative non-DPV patients; this constituted a nested case-control study. Subgroup analysis was based on the order of DPV before or after the occurrence of HCC. RESULTS: The incidence of acute kidney injury and intra-abdominal bleeding after LT in the DPV group was significantly higher than that in non-DPV group. The 5-year survival rates in the DPV and non-DPV group were 83.4% and 82.7% respectively (P = 0.930). In subgroup analysis, patients in the DPV prior to HCC subgroup may have a lower recurrence rate (4.7% vs.16.8%, P = 0.045) and a higher tumor free survival rate (88.9% vs.74.4%, P = 0.044) after LT under the up-to-date TNMI-II stage, while in TNM III stage, there was no difference for DPV prior to HCC subgroup compared with the DPV after HCC subgroup or the non-DPV group. CONCLUSION: Compared with DPV after HCC, DPV treatment before HCC can reduce the recurrence rate of HCC after early transplantation (TNM I-II). DPV before LT can reduce the recurrence of early HCC.


Asunto(s)
Carcinoma Hepatocelular , Hipertensión Portal , Neoplasias Hepáticas , Trasplante de Hígado , Recurrencia Local de Neoplasia , Vena Porta , Humanos , Trasplante de Hígado/efectos adversos , Carcinoma Hepatocelular/cirugía , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/mortalidad , Masculino , Femenino , Vena Porta/patología , Vena Porta/cirugía , Persona de Mediana Edad , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/mortalidad , Estudios de Casos y Controles , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/patología , Hipertensión Portal/cirugía , Hipertensión Portal/complicaciones , Anciano , Adulto
13.
Nephrol Dial Transplant ; 39(6): 967-977, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38262746

RESUMEN

BACKGROUND: Postoperative acute kidney injury (AKI) is a common condition after surgery, however, the available data about nationwide epidemiology of postoperative AKI in China from large and high-quality studies are limited. This study aimed to determine the incidence, risk factors and outcomes of postoperative AKI among patients undergoing surgery in China. METHODS: This was a large, multicentre, retrospective study performed in 16 tertiary medical centres in China. Adult patients (≥18 years of age) who underwent surgical procedures from 1 January 2013 to 31 December 2019 were included. Postoperative AKI was defined by the Kidney Disease: Improving Global Outcomes creatinine criteria. The associations of AKI and in-hospital outcomes were investigated using logistic regression models adjusted for potential confounders. RESULTS: Among 520 707 patients included in our study, 25 830 (5.0%) patients developed postoperative AKI. The incidence of postoperative AKI varied by surgery type, which was highest in cardiac (34.6%), urologic (8.7%) and general (4.2%) surgeries. A total of 89.2% of postoperative AKI cases were detected in the first 2 postoperative days. However, only 584 (2.3%) patients with postoperative AKI were diagnosed with AKI on discharge. Risk factors for postoperative AKI included older age, male sex, lower baseline kidney function, pre-surgery hospital stay ≤3 days or >7 days, hypertension, diabetes mellitus and use of proton pump inhibitors or diuretics. The risk of in-hospital death increased with the stage of AKI. In addition, patients with postoperative AKI had longer lengths of hospital stay (12 versus 19 days) and were more likely to require intensive care unit care (13.1% versus 45.0%) and renal replacement therapy (0.4% versus 7.7%). CONCLUSIONS: Postoperative AKI was common across surgery type in China, particularly for patients undergoing cardiac surgery. Implementation and evaluation of an alarm system is important for the battle against postoperative AKI.


Asunto(s)
Lesión Renal Aguda , Complicaciones Posoperatorias , Humanos , Lesión Renal Aguda/etiología , Lesión Renal Aguda/epidemiología , Masculino , Femenino , China/epidemiología , Incidencia , Estudios Retrospectivos , Factores de Riesgo , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Anciano , Adulto , Mortalidad Hospitalaria
14.
J Surg Res ; 297: 63-70, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38447337

RESUMEN

INTRODUCTION: Diabetic foot ulcer (DFU) is a severe complication that threatens the daily lives of patients with diabetes and represents a serious challenge to the global health system. Considering that impaired wound healing is the leading cause of DFU, exploring the mechanism of diabetic wound healing is beneficial for improving DFU treatment. Resveratrol (RES) is a native polyphenol with various pharmacological characteristics, and recent studies have indicated an accelerated function of RES in diabetic wound healing. As human dermal fibroblasts (HDFs) play a significant role in diabetic wound healing, this study aimed to elucidate the regulatory mechanism of RES in HDFs. METHODS: To mimic diabetic wound healing in vitro, the HDFs were stimulated with high glucose (HG). Our findings revealed that RES reversed HG-induced suppression of HDF proliferation and migration caused by HG. RES inhibits the Notch signaling pathway. More importantly, we demonstrated that the activation of the Notch pathway abrogated the effects of RES on HG-induced HDFs. RESULTS: In vivo assays also illustrated that RES contributed to wound healing in diabetic mice by blocking the Notch pathway. CONCLUSIONS: In conclusion, RES improved diabetic wound healing by targeting the Notch pathway, which offers novel insights into DFU therapy.


Asunto(s)
Diabetes Mellitus Experimental , Pie Diabético , Humanos , Ratones , Animales , Resveratrol/farmacología , Diabetes Mellitus Experimental/metabolismo , Cicatrización de Heridas , Piel/metabolismo
15.
J Org Chem ; 89(3): 1858-1863, 2024 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-38215471

RESUMEN

Salpratone A (1), a novel abietane diterpenoid containing a unique cis-fused A/B ring, was isolated from Salvia prattii. Bioactivity studies showed that 1 has potent activity in inhibiting platelet aggregation induced by multiple agonists as well as antithrombotic efficacy in the FeCl3-induced rat in vivo thrombosis model. Furthermore, a bioinspired synthesis of 1 from the abundant natural product ferruginol was achieved in 6 steps with a 22% overall yield. The key steps include a stereoselective allyl oxidation and a subsequent regioselective Meinwald rearrangement.


Asunto(s)
Abietanos , Salvia , Animales , Ratas , Salvia/química , Abietanos/síntesis química
16.
BMC Neurol ; 24(1): 206, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886633

RESUMEN

BACKGROUND: Mutations in the SLC5A7 gene cause congenital myasthenia, a rare genetic disorder. Mutation points in the SLC5A7 gene differ among individuals and encompass various genetic variations; however, exon deletion variants have yet to be reported in related cases. This study aims to explore the clinical phenotype and genetic traits of a patient with congenital myasthenic syndrome due to SLC5A7 gene variation and those of their family members. CASE PRESENTATION: We describe a case of a Chinese male with congenital myasthenic syndrome presenting fluctuating limb weakness. Genetic testing revealed a heterozygous deletion mutation spanning exons 1-9 in the SLC5A7 gene. QPCR confirmed a deletion in exon 9 of the SLC5A7 gene in the patient's mother and brother. Clinical symptoms of myasthenia improved following treatment with pyridostigmine. CONCLUSION: Exons 1, 5, and 9 of the SLC5A7 gene encode the choline transporter's transmembrane region. Mutations in these exons can impact the stability and plasma membrane levels of the choline transporter. Thus, a heterozygous deletion in exons 1-9 of the SLC5A7 gene could be the pathogenic cause for this patient. In patients exhibiting fluctuating weakness, positive RNS, and seronegativity for myasthenia gravis antibodies, a detailed family history should be considered, and enhanced genetic testing is recommended to determine the cause.


Asunto(s)
Síndromes Miasténicos Congénitos , Humanos , Síndromes Miasténicos Congénitos/genética , Síndromes Miasténicos Congénitos/diagnóstico , Masculino , Mutación , Linaje , Adulto , Pruebas Genéticas/métodos , Femenino , Simportadores/genética
17.
Org Biomol Chem ; 22(11): 2241-2251, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38372133

RESUMEN

A novel cascade radical addition/cyclization reaction of non-activated olefins and oxamic acids has been proposed. Under transition metal-free conditions, 36 quinazolinone derivatives containing an amide moiety were successfully synthesized, with the highest yield being 81%. This method involves the preparation of aminoacyl fused quinazolinone derivatives under mild conditions, offering advantages such as a high yield, a broad substrate compatibility, and a high atom economy.

18.
Skeletal Radiol ; 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38695874

RESUMEN

OBJECTIVE: To determine which bones and which grades had the highest inter-rater variability when employing the Tanner-Whitehouse (T-W) method. MATERIALS AND METHODS: Twenty-four radiologists were recruited and trained in the T-W classification of skeletal development. The consistency and skill of the radiologists in determining bone development status were assessed using 20 pediatric hand radiographs of children aged 1 to 18 years old. Four radiologists had a poor concordance rate and were excluded. The remaining 20 radiologists undertook a repeat reading of the radiographs, and their results were analyzed by comparing them with the mean assessment of two senior experts as the reference standard. Concordance rate, scoring, and Kendall's W were calculated to evaluate accuracy and consistency. RESULTS: Both the radius, ulna, and short finger (RUS) system (Kendall's W = 0.833) and the carpal (C) system (Kendall's W = 0.944) had excellent consistency, with the RUS system outperforming the C system in terms of scores. The repeatability analysis showed that the second rating test, performed after 2 months of further bone age assessment (BAA) practice, was more consistent and accurate than the first. The capitate had the lowest average concordance rate and scoring, as well as the lowest overall concordance rate for its D classification. Moreover, the G classifications of the seven carpal bones all had a concordance rate less than 0.6. The bones with lower Kendall's W were likewise those with lower scores and concordance rates. CONCLUSION: The D grade of the capitate showed the highest variation, and the use of the Tanner-Whitehouse 3rd edition (T-W3) to determine bone age (BA) was frequently inconsistent. A more comprehensive description with a focus on inaccuracy bones or ratings and a modification to the T-W3 approach would significantly advance BAA.

19.
Plant Dis ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38902877

RESUMEN

Agave sisalana, as an excellent fiber producing plant, is mainly planted in Guangxi Province, China. In November 2023, a foliar disease occured on A. sisalana at Liangjiang Town (108.3593 W, 23.4723 N), Wuming District, Nanning in GuangXi, China. Approximately 50 to 60% of the plants (n=200) had obvious leaf spots on more than 70% of the leaves. On the leaves of sisal, circular or irregularly shaped yellow brown spots can be seen, sunken, with no halo on the edges. As time goes on, the lesion gradually expands to the entire blade of the sword (Figure 1A, 1B). To identify the disease etiology, ten agave leaves were collected from GuangXi. Symptomatic midribs were cut into 3×3 mm pieces, surface sterilized with 75 % ethanol for 20 s, rinsed with sterilized distilled water three times, air dried on sterile filter paper, plated on photo dextrose agar (PDA) medium, and incubated at 28 ℃ in the dark. Five isolates (JM01, JM02, JM03, JM05, JM06) with similar morphology were obtained. Colonies on PDA medium were white to grayish-white with atrial mycelia growing initially upward and then forming clusters (Figure 1E). After five days, mycelia turned grayish black. Immature conidia were initially hyaline, aseptate, and ellipsoid. Mature conidia were dark brown, one septate, longitudinal striate, and 22.1 to 26.3×10.2 to 14.9 µm (Figure 1F). Morphologically , the isolates were identified as Lasiodiplodia theobromae (Alves et al. 2008). For molecular identification, genome DNA of five representative isolate was extracted using the Fungi Genomic DNA Purification kit. The internal transcribed spacer (ITS) region of rDNA and translation elongation factor 1-alpha (TEF-1α) and ß-tublin (TUB) gene were amplified with primer pairs ITS1/ITS4 (White et al. 1990), EF1-728F/EF1-986R (Carbone and Kohn 1999), and Bt2a/Bt2b (Glass and Donaldson 1995), respectively, and sequenced. The ITS (PP209594), TEF-1α (PP234629), and TUB (PP234628) sequences of representative isolate JM01 were deposited in GeneBank. BLAST searches showed >99% nucleotide identity to sequences of L. theobromae (ITS, 99.26% to NR111174; TEF-1α, 99.69% to MM840490; TUB, 98.92% to MN172230). Phylogenetic analysis using maximum likelihood based on the combined ITS, TEF-1α, and TUB sequences of the isolates and reference sequences of Lasiodiplodias spp. from GenBank indicated the isolates obtained in this study formed a clade strongly supported based on bootstrap values to the ex-type isolate CBS164.96 sequences of L.theobromae (Figure 2). To test pathogenicity, JM01 was tested by inoculation leaves of one year old agave plants, the epidermis at the inoculation site, 10, 15 and 20 cm below to the crown, was wiped with a 75% alcohol cotton ball, washed three times with sterile water, and punctured (5 mm diameter) with a sterile inoculation needle. A 5 mm block of each isolate cultured on PDA for 3 days was attached to the inoculation site. Controls were inoculated with sterile PDA. The inoculation area was covered with plastic wrap. All plants were kept in a controlled greenhouse at 27℃, 80% relative humidity, and natural daylight, and watered weekly. Each treatment was repeated three times. Remove the block one day later. Three days after inoculation, all inoculated had typical symptoms,but control were healthy (Figure 1C, 1D). Fungal isolates were only recovered from symptomatic stems and were morphologically identical to L. theobromae, completing Koch's postulates. L. Theobromae has been reported as the cause of leaf rot on A. angustifolia in Mexico (Reyes-García et al. 2023). To our knowledge, this is the first report of L. theobromae causing leaf spot on A. sisalana in GuangXi, China. L. theobromae is primarily a plant pathogen that causes rotting and dieback in fruits and plants in tropical and subtropical regions (Puttanna 1967). This study is useful to focus on management strategies for leaf rot disease by L. theobromae of A. sisalana.

20.
Int J Mol Sci ; 25(15)2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39125636

RESUMEN

Dendrocalamus farinosus bamboo shoots, a species with rich nutritional value, are important in Southwest China. Lignin is an important factor affecting the postharvest flavor quality of bamboo shoots; however, the underlying mechanism of lignin deposition in D. farinosus bamboo shoots during cold storage is still not fully understood. In this study, the mutant D. farinosus XK4 with low lignin content at 3.11% and the cultivated variety ZPX at 4.47% were used as experimental materials. The lignin content of D. farinosus XK4 and ZPX, as well as the gene expression differences between them, were compared and analyzed during cold storage using transcriptomic and physiological methods. Our analysis revealed several key genes and found that D. farinosus CCoAOMT1 plays a key role in the regulatory network of bamboo shoots during cold storage. Tobacco heterologous transformation experiments demonstrated that overexpression of DfCCoAOMT1 significantly increases lignin content. This study provides a novel foundation for future research aimed at improving the postharvest quality and flavor of D. farinosus bamboo shoots through targeted genetic manipulation during cold storage.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Lignina , Proteínas de Plantas , Lignina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Frío , Brotes de la Planta/genética , Brotes de la Planta/metabolismo , Poaceae/genética , Poaceae/metabolismo , Metiltransferasas/genética , Metiltransferasas/metabolismo , Transcriptoma/genética
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