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1.
Cell ; 185(7): 1117-1129.e8, 2022 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-35298912

RESUMEN

Game animals are wildlife species traded and consumed as food and are potential reservoirs for SARS-CoV and SARS-CoV-2. We performed a meta-transcriptomic analysis of 1,941 game animals, representing 18 species and five mammalian orders, sampled across China. From this, we identified 102 mammalian-infecting viruses, with 65 described for the first time. Twenty-one viruses were considered as potentially high risk to humans and domestic animals. Civets (Paguma larvata) carried the highest number of potentially high-risk viruses. We inferred the transmission of bat-associated coronavirus from bats to civets, as well as cross-species jumps of coronaviruses from bats to hedgehogs, from birds to porcupines, and from dogs to raccoon dogs. Of note, we identified avian Influenza A virus H9N2 in civets and Asian badgers, with the latter displaying respiratory symptoms, as well as cases of likely human-to-wildlife virus transmission. These data highlight the importance of game animals as potential drivers of disease emergence.


Asunto(s)
Animales Salvajes/virología , Enfermedades Transmisibles Emergentes/virología , Reservorios de Enfermedades , Mamíferos/virología , Viroma , Animales , China , Filogenia , Zoonosis
2.
PLoS Pathog ; 19(10): e1011753, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37883598

RESUMEN

Virus genome recoding is an attenuation method that confers genetically stable attenuation by rewriting a virus genome with numerous silent mutations. Prior flavivirus genome recoding attempts utilised codon deoptimisation approaches. However, these codon deoptimisation approaches act in a species dependent manner and were unable to confer flavivirus attenuation in mosquito cells or in mosquito animal models. To overcome these limitations, we performed flavivirus genome recoding using the contrary approach of codon optimisation. The genomes of flaviviruses such as dengue virus type 2 (DENV2) and Zika virus (ZIKV) contain functional RNA elements that regulate viral replication. We hypothesised that flavivirus genome recoding by codon optimisation would introduce silent mutations that disrupt these RNA elements, leading to decreased replication efficiency and attenuation. We chose DENV2 and ZIKV as representative flaviviruses and recoded them by codon optimising their genomes for human expression. Our study confirms that this recoding approach of codon optimisation does translate into reduced replication efficiency in mammalian, human, and mosquito cells as well as in vivo attenuation in both mice and mosquitoes. In silico modelling and RNA SHAPE analysis confirmed that DENV2 recoding resulted in the extensive disruption of genomic structural elements. Serial passaging of recoded DENV2 resulted in the emergence of rescue or adaptation mutations, but no reversion mutations. These rescue mutations were unable to rescue the delayed replication kinetics and in vivo attenuation of recoded DENV2, demonstrating that recoding confers genetically stable attenuation. Therefore, our recoding approach is a reliable attenuation method with potential applications for developing flavivirus vaccines.


Asunto(s)
Culicidae , Flavivirus , Infección por el Virus Zika , Virus Zika , Humanos , Animales , Ratones , Flavivirus/genética , Virus Zika/genética , Replicación Viral/genética , Codón , Mamíferos
3.
J Am Chem Soc ; 146(18): 12519-12529, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38666300

RESUMEN

Na3V2(PO4)2F3 is recognized as a promising cathode for high energy density sodium-ion batteries due to its high average potential of ∼3.95 V (vs Na/Na+). A high-voltage-resistant electrolyte is of high importance due to the long duration of 4.2 V (vs Na/Na+) when improving cyclability. Herein, a targeted electrolyte containing additives with two -C≡N groups like succinonitrile has been designed. In this design, one -C≡N group is accessible to the solvation sheath and enables the other -C≡N in dinitrile being exposed and subsequently squeezed into the electric double layer. Then, the squeezed -C≡N group is prone to a preferential adsorption on the electrode surface prior to the exposed -CH2/-CH3 in Na+-solvent and oxidized to construct a stable and electrically insulating interface enriched CN-/NCO-/Na3N. The Na3V2(PO4)2F3-based sodium-ion batteries within a high-voltage of 2-4.3 V (vs Na/Na+) can accordingly achieve an excellent cycling stability (e.g., 95.07% reversible capacity at 1 C for 1,5-dicyanopentane and 98.4% at 2 C and 93.0% reversible capacity at 5 C for succinonitrile after 1000 cycles). This work proposes a new way to design high-voltage electrolytes for high energy density sodium-ion batteries.

4.
J Clin Immunol ; 44(6): 127, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38773005

RESUMEN

We described the diagnosis and treatment of a patient with autoinflammatory disease, named "Deficiency in ELF4, X-linked (DEX)". A novel ELF4 variant was discovered and its pathogenic mechanism was elucidated. The data about clinical, laboratory and endoscopic features, treatment, and follow-up of a patient with DEX were analyzed. Whole exome sequencing and Sanger sequencing were performed to identify potential pathogenic variants. The mRNA and protein levels of ELF4 were analyzed by qPCR and Western blotting, respectively. The association of ELF4 frameshift variant with nonsense-mediated mRNA decay (NMD) in the pathogenesis DEX was examined. Moreover, RNA-seq was performed to identify the key molecular events triggered by ELF4 variant. The relationship between ELF4 and IFN-ß activity was validated using a dual-luciferase reporter assay and a ChIP-qPCR assay. An 11-year-old boy presented with a Behçet's-like phenotype. The laboratory abnormality was the most obvious in elevated inflammatory indicators. Endoscopy revealed multiple ileocecal ulcers. Intestinal histopathology showed inflammatory cell infiltrations. The patient was treated with long-term immunosuppressant and TNF-α blocker (adalimumab), which reaped an excellent response over 16 months of follow-up. Genetic analysis identified a maternal hemizygote frameshift variant (c.1022del, p.Q341Rfs*30) in ELF4 gene in the proband. The novel variant decreased the mRNA level of ELF4 via the NMD pathway. Mechanistically, insufficient expression of ELF4 disturbed the immune system, leading to immunological disorders and pathogen susceptibility, and disrupted ELF4-activating IFN-ß responses. This analysis detailed the clinical characteristics of a Chinese patient with DEX who harbored a novel ELF4 frameshift variant. For the first time, we used patient-derived cells and carried out transcriptomic analysis to delve into the mechanism of ELF4 variant in DEX.


Asunto(s)
Mutación del Sistema de Lectura , Perfilación de la Expresión Génica , Niño , Humanos , Masculino , Secuenciación del Exoma , Predisposición Genética a la Enfermedad , Degradación de ARNm Mediada por Codón sin Sentido , Linaje , Proteínas Proto-Oncogénicas c-ets/genética , Factores de Transcripción/genética , Transcriptoma
5.
Plant Physiol ; 193(1): 483-501, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37311175

RESUMEN

Pentatricopeptide repeat (PPR) proteins form a large protein family and have diverse functions in plant development. Here, we identified an ALBINO EMBRYO AND SEEDLING (AES) gene that encodes a P-type PPR protein expressed in various tissues, especially the young leaves of Arabidopsis (Arabidopsis thaliana). Its null mutant aes exhibited a collapsed chloroplast membrane system, reduced pigment content and photosynthetic activity, decreased transcript levels of PEP (plastid-encoded polymerase)-dependent chloroplast genes, and defective RNA splicing. Further work revealed that AES could directly bind to psbB-psbT, psbH-petB, rps8-rpl36, clpP, ycf3, and ndhA in vivo and in vitro and that the splicing efficiencies of these genes and the expression levels of ycf3, ndhA, and cis-tron psbB-psbT-psbH-petB-petD decreased dramatically, leading to defective PSI, PSII, and Cyt b6f in aes. Moreover, AES could be transported into the chloroplast stroma via the TOC-TIC channel with the assistance of Tic110 and cpSRP54 and may recruit HCF244, SOT1, and CAF1 to participate in the target RNA process. These findings suggested that AES is an essential protein for the assembly of photosynthetic complexes, providing insights into the splicing of psbB operon (psbB-psbT-psbH-petB-petD), ycf3, and ndhA, as well as maintaining chloroplast homeostasis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Plantones/genética , Plantones/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Empalme del ARN/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Homeostasis , ARN del Cloroplasto/genética , ARN del Cloroplasto/metabolismo
6.
Plant Physiol ; 192(4): 2803-2821, 2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37144829

RESUMEN

Plants have evolved multiple mechanisms to cope with diverse types of light stress, particularly the regulation of the electron transport chain (ETC). Under high light (HL) conditions, the balance of electron flux in the ETC is disturbed, which leads to the overaccumulation of reactive oxygen species (ROS) and results in photodamage and photoinhibition. The cytochrome (Cyt) b6/f complex, which coordinates electron transfer between photosystems I and II (PSI and PSII), plays an essential role in regulating the ETC and initiating photoprotection. However, how the Cyt b6/f complex is maintained under HL conditions remains unclear. Here, we report that the activity of the Cyt b6/f complex is sustained by thylakoid-localized cyclophilin 37 (CYP37) in Arabidopsis (Arabidopsis thaliana). Compared with wild-type plants, cyp37 mutants displayed an imbalance in electron transport from Cyt b6/f to PSI under HL stress, which led to increased ROS accumulation, decreased anthocyanin biosynthesis, and increased chlorophyll degradation. Surprisingly, CYP37's role in regulating ETC balance was independent of photosynthesis control, which was indicated by a higher Y (ND), an indicator of P700 oxidation in PSI. Furthermore, the interaction between CYP37 and photosynthetic electron transfer A (PetA), a subunit of the Cyt b6/f complex, suggests that the central function of CYP37 is to maintain Cyt b6/f complex activity rather than to serve as an assembly factor. Our study provides insights into how plants balance electron flow between PSII and PSI via Cyt b6/f complex under HL.


Asunto(s)
Arabidopsis , Transporte de Electrón/fisiología , Arabidopsis/genética , Arabidopsis/metabolismo , Ciclofilinas/genética , Ciclofilinas/metabolismo , Citocromos b6/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Clorofila/metabolismo , Fotosíntesis/fisiología , Complejo de Proteína del Fotosistema I/genética , Complejo de Proteína del Fotosistema I/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Complejo de Citocromo b6f/genética , Complejo de Citocromo b6f/metabolismo , Plantas/metabolismo
7.
Cardiovasc Diabetol ; 23(1): 86, 2024 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-38419039

RESUMEN

BACKGROUND: Studies on the relationship between insulin resistance (IR) surrogates and long-term all-cause mortality in patients with coronary heart disease (CHD) and hypertension are lacking. This study aimed to explore the relationship between different IR surrogates and all-cause mortality and identify valuable predictors of survival status in this population. METHODS: The data came from the National Health and Nutrition Examination Survey (NHANES 2001-2018) and National Death Index (NDI). Multivariate Cox regression and restricted cubic splines (RCS) were performed to evaluate the relationship between homeostatic model assessment of IR (HOMA-IR), triglyceride glucose index (TyG index), triglyceride glucose-body mass index (TyG-BMI index) and all-cause mortality. The recursive algorithm was conducted to calculate inflection points when segmenting effects were found. Then, segmented Kaplan-Meier analysis, LogRank tests, and multivariable Cox regression were carried out. Receiver operating characteristic (ROC) and calibration curves were drawn to evaluate the differentiation and accuracy of IR surrogates in predicting the all-cause mortality. Stratified analysis and interaction tests were conducted according to age, gender, diabetes, cancer, hypoglycemic and lipid-lowering drug use. RESULTS: 1126 participants were included in the study. During the median follow-up of 76 months, 455 participants died. RCS showed that HOMA-IR had a segmented effect on all-cause mortality. 3.59 was a statistically significant inflection point. When the HOMA-IR was less than 3.59, it was negatively associated with all-cause mortality [HR = 0.87,95%CI (0.78, 0.97)]. Conversely, when the HOMA-IR was greater than 3.59, it was positively associated with all-cause mortality [HR = 1.03,95%CI (1.00, 1.05)]. ROC and calibration curves indicated that HOMA-IR was a reliable predictor of survival status (area under curve = 0,812). No interactions between HOMA-IR and stratified variables were found. CONCLUSION: The relationship between HOMA-IR and all-cause mortality was U-shaped in patients with CHD and hypertension. HOMA-IR was a reliable predictor of all-cause mortality in this population.


Asunto(s)
Enfermedad Coronaria , Hipertensión , Resistencia a la Insulina , Humanos , Estudios Longitudinales , Encuestas Nutricionales , Glucemia , Estudios de Cohortes , Hipertensión/diagnóstico , Enfermedad Coronaria/diagnóstico , Triglicéridos , Glucosa , Biomarcadores
8.
J Exp Bot ; 75(4): 1187-1204, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-37948577

RESUMEN

PHYTOENE SYNTHASE (PSY) is a rate-limiting enzyme catalysing the first committed step of carotenoid biosynthesis, and changes in PSY gene expression and/or protein activity alter carotenoid composition and plastid differentiation in plants. Four genetic variants of PSY (psy-4, psy-90, psy-130, and psy-145) were identified using a forward genetics approach that rescued leaf virescence phenotypes and plastid abnormalities displayed by the Arabidopsis CAROTENOID ISOMERASE (CRTISO) mutant ccr2 (carotenoid and chloroplast regulation 2) when grown under a shorter photoperiod. The four non-lethal mutations affected alternative splicing, enzyme-substrate interactions, and PSY:ORANGE multi-enzyme complex binding, constituting the dynamic post-transcriptional fine-tuning of PSY levels and activity without changing localization to the stroma and protothylakoid membranes. psy genetic variants did not alter total xanthophyll or ß-carotene accumulation in ccr2, yet they reduced specific acyclic linear cis-carotenes linked to the biosynthesis of a currently unidentified apocarotenoid signal regulating plastid biogenesis, chlorophyll biosynthesis, and photomorphogenic regulation. ccr2 psy variants modulated the PHYTOCHROME-INTERACTING FACTOR 3/ELONGATED HYPOCOTYL 5 (PIF3/HY5) ratio, and displayed a normal prolamellar body formation in etioplasts and chlorophyll accumulation during seedling photomorphogenesis. Thus, suppressing PSY activity and impairing PSY:ORANGE protein interactions revealed how cis-carotene abundance can be fine-tuned through holoenzyme-metabolon interactions to control plastid development.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Geranilgeranil-Difosfato Geranilgeraniltransferasa/genética , Arabidopsis/metabolismo , Carotenoides/metabolismo , Plastidios/genética , Plastidios/metabolismo , Clorofila/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo
9.
Clin Transplant ; 38(2): e15247, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38375911

RESUMEN

BACKGROUND: The role of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients <3 years of age remains controversial. Data on haploidentical donor (HID) transplants in this age group is limited. PATIENTS AND METHODS: We retrospectively analyzed the prognosis of 97 patients with acute leukemia aged <3 years who underwent HID transplantation at our institute. RESULTS: With a median follow-up of 45 months, the 3-year disease-free survival (DFS), overall survival (OS), and 3-year cumulative incidence rate of treatment-related mortality were 69.3% (95% confidence interval (CI): 59.9%-78.7%), 74.2% (95% CI: 65.2%-83.2%), and 3.6% (95% CI: 0.9%-9.7%) in all 97 patients, respectively. The 3-year DFS and OS rate in patients diagnosed <1 year and patients diagnosed ≥1 year were comparable: 77.8% (95% CI: 62.2%-93.4%) versus 66.3% (95% CI: 55.0%-77.6%, p = .253) and 82.5% (95% CI: 66.3-98.7%) versus 72.8% (95% CI: 61.9%-83.7%, p = .153), respectively. At the last follow-up, 23 patients had died, and 20 had died of relapse. Multivariate analysis revealed that positive pre-HSCT flow cytometric minimal residual disease (hazard ratio 5.605, p = .000) and AML-M7 expression (hazard ratio 2.906, p = .014) were independent adverse prognostic variables for relapse. CONCLUSIONS: HID transplantation is potent and safe for infants and young patients with acute leukemia. Relapse is the primary cause of treatment failure.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Humanos , Preescolar , Estudios Retrospectivos , Trasplante Homólogo , Leucemia Mieloide Aguda/terapia , Pronóstico , Enfermedad Aguda , Enfermedad Crónica , Recurrencia
10.
J Appl Toxicol ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38700028

RESUMEN

This study demonstrated that both copper oxide nanoparticles (CuO-NPs) and copper nanoparticles (Cu-NPs) can cause swelling, inflammation, and cause damage to the mitochondria of alveolar type II epithelial cells in mice. Cellular examinations indicated that both CuO-NPs and Cu-NPs can reduce cell viability and harm the mitochondria of human bronchial epithelial cells, particularly Beas-2B cells. However, it is clear that CuO-NPs exhibit a more pronounced detrimental effect compared with Cu-NPs. Using bafilomycin A1 (Bafi A1), an inhibitor of lysosomal acidification, was found to enhance cell viability and alleviate mitochondrial damage caused by CuO-NPs. Additionally, Bafi A1 also reduces the accumulation of dihydrolipoamide S-acetyltransferase (DLAT), a marker for mitochondrial protein toxicity, induced by CuO-NPs. This observation suggests that the toxicity of CuO-NPs depends on the distribution of copper particles within cells, a process facilitated by the acidic environment of lysosomes. The release of copper ions is thought to be triggered by the acidic conditions within lysosomes, which aligns with the lysosomal Trojan horse mechanism. However, this association does not seem to be evident with Cu-NPs.

11.
J Stroke Cerebrovasc Dis ; 33(8): 107763, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38723921

RESUMEN

OBJECTIVE: To assess the utility of combined neutrophil-to-lymphocyte ratio (NLR) and D-dimer detection in determining the severity and short-term prognosis of acute cardiogenic cerebral embolism (ACCE) in older adults. METHODS: We selected 202 elderly non-valvular atrial fibrillation patients hospitalized at the Third Affiliated Hospital of Anhui Medical University from April 1, 2020, to April 1, 2023. They were divided into an observation group (69 cases combined with ACCE) and a control group (133 cases with non-valvular atrial fibrillation alone) based on whether acute cardioembolic cerebral embolism occurred. According to the National Institutes of Health Stroke Scale (NIHSS), the observation group was divided into a mild cerebral infarction group (MICI group), a moderate cerebral infarction group (MOCI group), and a severe cerebral infarction group (SCI group), with 26 cases, 29 cases, and 14 cases, respectively. According to the modified Rankin scale (mRS), after 3 months, 30 cases were divided into the good prognosis group and 39 cases were divided into the poor prognosis group. We detected and compared the differences in D-dimer and NLR levels among different groups of patients, as well as differences in some important laboratory indicators. Logistic regression analysis was used to identify factors influencing the short-term prognosis of patients with acute cardioembolic cerebral infarction, and ROC curves were plotted to evaluate the value of D-dimer and NLR in predicting the short-term prognosis of patients with acute cardioembolic cerebral infarction. RESULTS: The levels of D-dimer and NLR in peripheral blood in SCI group [1.82 (0.58-6.71) mg/l, 4.55 (3.14,7.21)] were higher than those in MOCI group [1.16 (0.65-1.90) mg/l, 3.84 (2.31,6.68)] and MICI group [0.53 (0.32-0.90) mg/l, 2.46 (2.09-3.79)]. The difference between groups was statistically significant (P < 0.05). Logistic regression analysis showed that D-dimer and NLR were independent risk factors for poor prognosis in patients with acute cardiogenic cerebral embolism (OR values were 1.772 and 1.603, and 95 %CI were 1.060-2.963 and 1.100-2.338, respectively, both P < 0.05). The AUC for the prediction of poor prognosis in acute cardioembolic stroke by combining D-dimer and NLR was 0.812 [95 % CI: 0.710-0.914], higher than the individual detections of D-dimer at 0.756 [95% CI: 0.642-0.869] and NLR at 0.733 [95 % CI: 0.613-0.854]. CONCLUSION: Peripheral blood D-dimer combined with NLR detection is helpful for the risk stratification and short-term prognosis assessment of patients with acute cardiogenic cerebral embolism. Clinical detection is of great significance for the prevention and monitoring of disease development.

12.
Int J Mol Sci ; 25(12)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38928476

RESUMEN

Salt stress seriously affects crop growth, leading to a decline in crop quality and yield. Application of exogenous substances to improve the salt tolerance of crops and promote their growth under salt stress has become a widespread and effective means. Eugenol is a small molecule of plant origin with medicinal properties such as antibacterial, antiviral, and antioxidant properties. In this study, tobacco seedlings were placed in Hoagland's solution containing NaCl in the presence or absence of eugenol, and physiological indices related to stress tolerance were measured along with transcriptome sequencing. The results showed that eugenol improved the growth of tobacco seedlings under salt stress. It promoted carbon and nitrogen metabolism, increased the activities of nitrate reductase (NR), sucrose synthase (SS), and glutamine synthetase (GS) by 31.03, 5.80, and 51.06%. It also activated the enzymatic and non-enzymatic antioxidant systems, reduced the accumulation of reactive oxygen species in the tobacco seedlings, and increased the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) by 24.38%, 18.22%, 21.60%, and 28.8%, respectively. The content of glutathione (GSH) was increased by 29.49%, and the content of superoxide anion (O2-) and malondialdehyde (MDA) were reduced by 29.83 and 33.86%, respectively. Promoted osmoregulation, the content of Na+ decreased by 34.34, K+ increased by 41.25%, and starch and soluble sugar increased by 7.72% and 25.42%, respectively. It coordinated hormone signaling in seedlings; the content of abscisic acid (ABA) and gibberellic acid 3 (GA3) increased by 51.93% and 266.28%, respectively. The transcriptome data indicated that the differentially expressed genes were mainly enriched in phenylpropanoid biosynthesis, the MAPK signaling pathway, and phytohormone signal transduction pathways. The results of this study revealed the novel role of eugenol in regulating plant resistance and provided a reference for the use of exogenous substances to alleviate salt stress.


Asunto(s)
Antioxidantes , Eugenol , Regulación de la Expresión Génica de las Plantas , Nicotiana , Reguladores del Crecimiento de las Plantas , Estrés Salino , Plantones , Transducción de Señal , Nicotiana/efectos de los fármacos , Nicotiana/metabolismo , Nicotiana/genética , Plantones/efectos de los fármacos , Plantones/metabolismo , Plantones/crecimiento & desarrollo , Antioxidantes/metabolismo , Transducción de Señal/efectos de los fármacos , Eugenol/farmacología , Eugenol/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Estrés Salino/efectos de los fármacos , Reguladores del Crecimiento de las Plantas/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Tolerancia a la Sal/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
13.
J Am Chem Soc ; 145(34): 19049-19059, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37589099

RESUMEN

Given the importance and beneficial characteristics of decorated azetidines in medicinal chemistry, efficient strategies for their synthesis are highly sought after. Herein, we report a facile synthesis of the elusive all-carbon quaternary-center-bearing azetidines. By adopting a well-orchestrated polar-radical relay strategy, ring strain release of bench-stable benzoylated 1-azabicyclo[1.1.0]butane (ABB) can be harnessed for nickel-catalyzed Suzuki Csp2-Csp3 cross-coupling with commercially available boronic acids in broad scope (>50 examples), excellent functional group tolerance, and gram-scale utility. Preliminary mechanistic studies provided insights into the underlying mechanism, wherein the ring opening of ABB with a catalytic quantity of bromide accounts for the conversion of ABB into a redox-active azetidine, which subsequently engages in the cross-coupling reaction through a radical pathway. The synergistic bromide and nickel catalysis could intriguingly be derived from a single nickel source (NiBr2). Application of the method to modify natural products, biologically relevant molecules, and pharmaceuticals has been successfully achieved as well as the synthesis of melanocortin-1 receptor (MC-1R) agonist and vesicular acetylcholine transporter (VAChT) inhibitor analogues through bioisosteric replacements of piperidine with azetidine moieties, highlighting the potential of the method in drug optimization studies. Aside from the synthesis of azetidines, we demonstrate the ancillary utility of our nickel catalytic system toward the restricted Suzuki cross-coupling of tertiary alkyl bromides with aryl boronic acids to construct all-carbon quaternary centers.

14.
Emerg Infect Dis ; 29(3): 576-584, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36823029

RESUMEN

Candida haemulonii, a relative of C. auris, frequently shows antifungal resistance and is transmissible. However, molecular tools for genotyping and investigating outbreaks are not yet established. We performed genome-based population analysis on 94 C. haemulonii strains, including 58 isolates from China and 36 other published strains. Phylogenetic analysis revealed that C. haemulonii can be divided into 4 clades. Clade 1 comprised strains from China and other global strains; clades 2-4 contained only isolates from China, were more recently evolved, and showed higher antifungal resistance. Four regional epidemic clusters (A, B, C, and D) were identified in China, each comprising ≥5 cases (largest intracluster pairwise single-nucleotide polymorphism differences <50 bp). Cluster A was identified in 2 hospitals located in the same city, suggesting potential intracity transmissions. Cluster D was resistant to 3 classes of antifungals. The emergence of more resistant phylogenetic clades and regional dissemination of antifungal-resistant C. haemulonii warrants further monitoring.


Asunto(s)
Antifúngicos , Candida , Candidiasis , Farmacorresistencia Fúngica , Antifúngicos/uso terapéutico , Candida/efectos de los fármacos , Candida/genética , Candidiasis/tratamiento farmacológico , Candidiasis/genética , Candidiasis/microbiología , China , Pruebas de Sensibilidad Microbiana , Filogenia , Células Clonales , Farmacorresistencia Fúngica/genética
15.
Hum Brain Mapp ; 44(9): 3493-3505, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-36988425

RESUMEN

Music shows tremendous promise in pain relief, especially when considering its non-pharmacological nature. However, our understanding of the precise mechanisms behind music-induced analgesia (MIA) remains poor. The positive emotional state induced by music is one of the key components explaining MIA. To test this possibility and reveal its neural correlates, the present study applied nociceptive laser stimuli to 28 healthy participants when their liked or disliked songs were played as background music, or when they were resting in silence. Differences among conditions were quantified by self-reports of pain intensity and unpleasantness, as well as brain activations in response to acute laser stimuli. As expected, liked music significantly lowered pain ratings to acute painful stimuli compared to disliked music and no music. Consistent with this observation, brain activations in response to acute painful stimuli were deceased within brain areas encoding sensory components of pain, such as the right precentral and postcentral gyri (PreCG/PoCG), brain areas related to affective components of pain, such as the anterior cingulate cortex and bilateral putamen, and brain areas associated with motor control and avoidance reactions to pain, such as the left cerebellum, when liked music was played in the background in comparison to disliked music. Importantly, the relationship between music listening and differences in pain ratings of two music conditions was mediated by the magnitude of right PreCG/PoCG and left cerebellum activations. These findings deepened our understanding of the analgesic benefits of background liked music, a property relevant to clinical applications.


Asunto(s)
Emociones , Música , Humanos , Emociones/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Música/psicología , Dolor/psicología , Percepción del Dolor , Mapeo Encefálico , Imagen por Resonancia Magnética
16.
J Transl Med ; 21(1): 921, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-38115075

RESUMEN

BACKGROUND: Metabolic dysfunction-associated fatty liver disease (MAFLD) is one of the most prevalent metabolic syndromes worldwide. However, no approved pharmacological treatments are available for MAFLD. Chenpi, one kind of dried peel of citrus fruits, has traditionally been utilized as a medicinal herb for liver diseases. Didymin is a newly identified oral bioactive dietary flavonoid glycoside derived from Chenpi. In this study, we investigated the therapeutic potential of Didymin as an anti-MAFLD drug and elucidated its underlying mechanisms. METHODS: High-fat diet (HFD)-induced MAFLD mice and alpha mouse liver 12 (AML12) cells were utilized to evaluate the effects and mechanisms of Didymin in the treatment of MAFLD. Liver weight, serum biochemical parameters, and liver morphology were examined to demonstrate the therapeutic efficacy of Didymin in MAFLD treatment. RNA-seq analysis was performed to identify potential pathways that could be affected by Didymin. The impact of Didymin on Sirt1 was corroborated through western blot, molecular docking analysis, microscale thermophoresis (MST), and deacetylase activity assay. Then, a Sirt1 inhibitor (EX-527) was utilized to confirm that Didymin alleviates MAFLD via Sirt1. Western blot and additional assays were used to investigate the underlying mechanisms. RESULTS: Our results suggested that Didymin may possess therapeutic potential against MAFLD in vitro and in vivo. By promoting Sirt1 expression as well as directly binding to and activating Sirt1, Didymin triggers downstream pathways that enhance mitochondrial biogenesis and function while reducing apoptosis and enhancing lipophagy. CONCLUSIONS: These suggest that Didymin could be a promising medication for MAFLD treatment. Furthermore, its therapeutic effects are mediated by Sirt1.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Sirtuina 1 , Animales , Ratones , Sirtuina 1/metabolismo , Biogénesis de Organelos , Simulación del Acoplamiento Molecular , Flavonoides/farmacología , Flavonoides/uso terapéutico , Glicósidos/farmacología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Hígado/metabolismo
17.
BMC Microbiol ; 23(1): 341, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37974063

RESUMEN

BACKGROUND: Candida glabrata is an important cause of invasive candidiasis. Echinocandins are the first-line treatment of invasive candidiasis caused by C. glabrata. The epidemiological echinocandin sensitivity requires long-term surveillance and the understanding about whole genome characteristics of echinocandin non-susceptible isolates was limited. RESULTS: The present study investigated the echinocandin susceptibility of 1650 C. glabrata clinical isolates in China from August 2014 to July 2019. The in vitro activity of micafungin was significantly better than those of caspofungin and anidulafungin (P < 0.001), assessed by MIC50/90 values. Whole genome sequencing was conducted on non-susceptible isolates and geography-matched susceptible isolates. Thirteen isolates (0.79%) were resistant to at least one echinocandin. Six isolates (0.36%) were solely intermediate to caspofungin. Common evolutionary analysis of echinocandin-resistant and echinocandin-intermediate isolates revealed genes related with reduced caspofungin sensitivity, including previously identified sphinganine hydroxylase encoding gene SUR2. Genome-wide association study identified SNPs at subtelometric regions that were associated with echinocandin non-susceptibility. In-host evolution of echinocandin resistance of serial isolates revealed an enrichment for non-synonymous mutations in adhesins genes and loss of subtelometric regions containing adhesin genes. CONCLUSIONS: The echinocandins are highly active against C. glabrata in China with a resistant rate of 0.79%. Echinocandin non-susceptible isolates carried common evolved genes which are related with reduced caspofungin sensitivity. In-host evolution of C. glabrata accompanied intensive changing of adhesins profile.


Asunto(s)
Candidiasis Invasiva , Equinocandinas , Humanos , Equinocandinas/farmacología , Equinocandinas/genética , Equinocandinas/uso terapéutico , Candida glabrata/genética , Caspofungina/farmacología , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Estudio de Asociación del Genoma Completo , Pruebas de Sensibilidad Microbiana , Candidiasis Invasiva/tratamiento farmacológico , China , Farmacorresistencia Fúngica/genética
18.
Hepatology ; 75(3): 646-660, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34510484

RESUMEN

BACKGROUND AND AIMS: Aging exacerbates liver neutrophil infiltration and alcohol-associated liver disease (ALD) in mice and humans, but the underlying mechanisms remain obscure. This study aimed to examine the effect of aging and alcohol consumption on neutrophilic Sirtuin 1 (SIRT1) and microRNA-223 (miR-223), and their contribution to ALD pathogeneses. APPROACH AND RESULTS: Young and aged myeloid-specific Sirt1 knockout mice were subjected to chronic-plus-binge ethanol feeding. Blood samples from healthy controls and patients with chronic alcohol drinking who presented with acute intoxication were analyzed. Neutrophilic Sirt1 and miR-223 expression were down-regulated in aged mice compared with young mice. Deletion of the Sirt1 gene in myeloid cells including neutrophils exacerbated chronic-plus-binge ethanol-induced liver injury and inflammation and down-regulated neutrophilic miR-223 expression. Immunoprecipitation experiments revealed that SIRT1 promoted C/EBPα deacetylation by directly interacting with C/EBPα, a key transcription factor that controls miR-223 biogenesis, and subsequently elevated miR-223 expression in neutrophils. Importantly, down-regulation of SIRT1 and miR-223 expression was also observed in circulating neutrophils from middle-aged and elderly subjects compared with those from young individuals. Chronic alcohol users with acute intoxication had a reduction in neutrophilic SIRT1 expression in young and middle-aged patients, with a greater reduction in the latter group. The neutrophilic SIRT1 expression correlated with neutrophilic miR-223 and serum alanine transaminase levels in those patients. CONCLUSIONS: Aging increases the susceptibility of alcohol-induced liver injury in mice and humans through the down-regulation of the neutrophilic SIRT1-C/EBPα-miR-223 axis, which could be a therapeutic target for the prevention and/or treatment of ALD.


Asunto(s)
Envejecimiento/fisiología , Hepatopatías Alcohólicas , Hígado , MicroARNs , Infiltración Neutrófila/fisiología , Sirtuina 1/metabolismo , Factores de Edad , Consumo de Bebidas Alcohólicas/efectos adversos , Animales , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/patología , Regulación hacia Abajo , Regulación de la Expresión Génica , Humanos , Hígado/metabolismo , Hígado/patología , Hepatopatías Alcohólicas/metabolismo , Hepatopatías Alcohólicas/patología , Ratones , Ratones Noqueados , MicroARNs/biosíntesis , MicroARNs/metabolismo , Células Mieloides/metabolismo , Sirtuina 1/genética
19.
Plant Cell Environ ; 46(3): 850-864, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36573466

RESUMEN

The maintenance of a proton gradient across the thylakoid membrane is an integral aspect of photosynthesis that is mainly established by the splitting of water molecules in photosystem II and plastoquinol oxidation at the cytochrome complex, and it is necessary for the generation of ATP in the last step of photophosphorylation. Although environmental stresses, such as high temperatures, are known to disrupt this fundamental process, only a few studies have explored the molecular mechanisms underlying proton gradient regulation during stress. The present study identified a heat-sensitive mutant that displays aberrant photosynthesis at high temperatures. This mutation was mapped to AtFtsH11, which encodes an ATP-dependent AAA-family metalloprotease. We showed that AtFtsH11 localizes to the chloroplast inner envelope membrane and is capable of degrading the ATP synthase assembly factor BFA3 under heat stress. We posit that this function limits the amount of ATP synthase integrated into the thylakoid membrane to regulate proton efflux from the lumen to the stroma. Our data also suggest that AtFtsH11 is critical in stabilizing photosystem II and cytochrome complexes at high temperatures, and additional studies can further elucidate the specific molecular functions of this critical regulator of photosynthetic thermotolerance.


Asunto(s)
Arabidopsis , ATPasas de Translocación de Protón de Cloroplastos , ATPasas de Translocación de Protón de Cloroplastos/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Protones , Arabidopsis/genética , Arabidopsis/metabolismo , Cloroplastos/metabolismo , Fotosíntesis/fisiología , Respuesta al Choque Térmico , Adenosina Trifosfato/metabolismo , Citocromos/metabolismo
20.
Opt Express ; 31(11): 18567-18575, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37381566

RESUMEN

The realization of red-emitting InGaN quantum well (QW) is a hot issue in current nitride semiconductor research. It has been shown that using a low-Indium (In)-content pre-well layer is an effective method to improve the crystal quality of red QWs. On the other hand, keeping uniform composition distribution at higher In content in red QWs is an urgent problem to be solved. In this work, the optical properties of blue pre-QW and red QWs with different well width and growth conditions are investigated by photoluminescence (PL). The results prove that the higher-In-content blue pre-QW is beneficial to effectively relieve the residual stress. Meanwhile, higher growth temperature and growth rate can improve the uniformity of In content and the crystal quality of red QWs, enhancing the PL emission intensity. Possible physical process of stress evolution and the model of In fluctuation in the subsequent red QW are discussed. This study provides a useful reference for the development of InGaN-based red emission materials and devices.

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