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Spin-crossover (SCO) materials exhibit remarkable potential as bistable switches in molecular devices. However, the spin transition temperatures (Tc) of known compounds are unable to cover the entire ambient temperature spectrum, largely limiting their practical utility. This study reports an exemplary two-dimensional SCO solid solution system, [FeIII(H0.5LCl)2-2x(H0.5LF)2x]·H2O (H0.5LX = 5-X-2-hydroxybenzylidene-hydrazinecarbothioamide, X = F or Cl, x = 0 to 1), in which the adjacent layers are adhered via hydrogen bonding. Notably, the Tc of this system can be fine-tuned across 90 K (227-316 K) in a linear manner by modulating the fraction x of the LF ligand. Elevating x results in strengthened hydrogen bonding between adjacent layers, which leads to enhanced intermolecular interactions between adjacent SCO molecules. Single-crystal diffraction analysis and periodic density functional theory calculations revealed that such a special kind of alteration in interlayer interactions strengthens the FeIIIN2O2S2 ligand field and corresponding SCO energy barrier, consequently resulting in increased Tc. This work provides a new pathway for tuning the Tc of SCO materials through delicate manipulation of molecular interactions, which could expand the application of bistable molecular solids to a much wider temperature regime.
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BACKGROUND: Cellular senescence frequently occurs during anti-cancer treatment, and persistent senescent tumor cells (STCs) unfavorably promote tumor progression through paracrine secretion of the senescence-associated secretory phenotype (SASP). Extracellular vesicles (EVs) have recently emerged as a novel component of the SASP and primarily mediate the tumor-promoting effect of the SASP. Of note, the potential effect of EVs released from STCs on tumor progression remains largely unknown. METHODS: We collected tumor tissues from two cohorts of colorectal cancer (CRC) patients to examine the expression of p16, p21, and SERPINE1 before and after anti-cancer treatment. Cohort 1 included 22 patients with locally advanced rectal cancer (LARC) who received neoadjuvant therapy before surgical resection. Cohort 2 included 30 patients with metastatic CRC (mCRC) who received first-line irinotecan-contained treatment. CCK-8, transwell, wound-healing assay, and tumor xenograft experiments were carried out to determine the impacts of EVs released from STCs on CRC progression in vitro and in vivo. Quantitative proteomic analysis was applied to identify protein cargo inside EVs secreted from STCs. Immunoprecipitation and mass spectrometer identification were utilized to explore the binding partners of SERPINE1. The interaction of SERPINE1 with p65 was verified by co-immunoprecipitation, and their co-localization was confirmed by immunofluorescence. RESULTS: Chemotherapeutic agents and irradiation could potently induce senescence in CRC cells in vitro and in human CRC tissues. The more significant elevation of p16 and p21 expression in patients after anti-cancer treatment displayed shorter disease-free survival (DFS) for LARC or progression-free survival (PFS) for mCRC. We observed that compared to non-STCs, STCs released an increased number of EVs enriched in SERPINE1, which further promoted the progression of recipient cancer cells. Targeting SERPINE1 with a specific inhibitor, tiplaxtinin, markedly attenuated the tumor-promoting effect of STCs-derived EVs. Additionally, the patients with greater increment of SERPINE1 expression after anti-cancer treatment had shorter DFS for LARC or PFS for mCRC. Mechanistically, SERPINE1 bound to p65, promoting its nuclear translocation and subsequently activating the NF-κB signaling pathway. CONCLUSIONS: We provide the in vivo evidence of the clinical prognostic implications of therapy-induced senescence. Our results revealed that STCs were responsible for CRC progression by producing large amounts of EVs enriched in SERPINE1. These findings further confirm the crucial role of therapy-induced senescence in tumor progression and offer a potential therapeutic strategy for CRC treatment.
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Neoplasias Colorretais , Vesículas Extracelulares , Neoplasias Retais , Humanos , NF-kappa B/metabolismo , Proteômica , Transdução de Sinais , Vesículas Extracelulares/metabolismo , Neoplasias Retais/metabolismo , Senescência Celular , Neoplasias Colorretais/patologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Inibidor 1 de Ativador de Plasminogênio/farmacologiaRESUMO
Heart failure (HF) can be caused by a variety of causes characterized by abnormal myocardial systole and diastole. Ca2+ current through the L-type calcium channel (LTCC) on the membrane is the initial trigger signal for a cardiac cycle. Declined systole and diastole in HF are associated with dysfunction of myocardial Ca2+ function. This disorder can be correlated with unbalanced levels of phosphorylation / dephosphorylation of LTCC, endoplasmic reticulum (ER), and myofilament. Kinase and phosphatase activity changes along with HF progress, resulting in phased changes in the degree of phosphorylation / dephosphorylation. It is important to realize the phosphorylation / dephosphorylation differences between a normal and a failing heart. This review focuses on phosphorylation / dephosphorylation changes in the progression of HF and summarizes the effects of phosphorylation / dephosphorylation of LTCC, ER function, and myofilament function in normal conditions and HF based on previous experiments and clinical research. Also, we summarize current therapeutic methods based on abnormal phosphorylation / dephosphorylation and clarify potential therapeutic directions.
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Cálcio , Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Fosforilação , Cálcio/metabolismo , Canais de Cálcio Tipo L/metabolismo , Retículo Endoplasmático/metabolismo , Miocárdio/metabolismo , Miofibrilas/metabolismoRESUMO
In brief: The mechanism underlying the accumulation of γδT cells in the decidua, which helps maintain maternal-fetal immunotolerance in early pregnancy, is unknown. This study reveals that DSC-derived RANKL upregulates ICAM-1 expression via the NF-κB pathway to enable γδT cell accumulation in the early decidua. Abstract: Decidual γδT (dγδT) cells help maintain maternal-fetal immunotolerance in early pregnancy. However, the mechanism underlying the accumulation of γδT cells in the decidua is unknown. Previous work showed that RANKL upregulated intercellular adhesion molecule 1 (ICAM-1) in decidual stromal cells (DSCs), and Rankl knockout mice had limited dγδT cell populations. In this study, we measured the expression levels of RANKL/RANK and ICAM-1 in DSCs, in addition to the integrins of ICAM-1 on dγδT cells, and the number of dγδT cells from patients with recurrent spontaneous abortion (RSA) and normal pregnant women in the first trimester. RSA patients showed significantly decreased RANKL/RANK and ICAM-1/CD11a signaling in decidua, and a decreased percentage of dγδT cells, which was positively correlated with DSC-derived RANKL and ICAM-1. Next, an in vitro adhesion experiment showed that the enhanced attraction of human DSCs to dγδT cells after RANKL overexpression was almost completely aborted by anti-ICAM-1. Furthermore, Rankl knockout mice showed a significant reduction in NF-κB activity compared with wild-type controls. Finally, we applied a selective NF-κB inhibitor named PDTC to validate the role of NF-κB in RANKL-mediated ICAM-1 upregulation. Taken together, our data show that DSC-derived RANKL upregulates ICAM-1 expression via the NF-κB pathway to enable γδT cell accumulation in the early decidua. A reduction in RANKL/ICAM-1 signaling in DSCs may result in insufficient accumulation of γδT cells in decidua and, in turn, RSA.
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Decídua , Molécula 1 de Adesão Intercelular , NF-kappa B , Ligante RANK , Regulação para Cima , Adulto , Animais , Feminino , Humanos , Camundongos , Gravidez , Decídua/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Molécula 1 de Adesão Intercelular/genética , Camundongos Knockout , NF-kappa B/metabolismo , Ligante RANK/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Transdução de Sinais , Células Estromais/metabolismo , Linfócitos T/metabolismoRESUMO
Oocyte activation failure, one of the main factors of total fertilization failure (TFF) after ICSI, could be induced by abnormal calcium oscillations. Phospholipase C zeta (PLCζ), a sperm factor, was associated with Ca2+ oscillations in oocytes of mammals. To date, only a limited number of mutations in PLCZ1 (the gene encodes PLCζ) have been linked to TFF demonstrated by the observed reduction in protein levels or activity. In this study, males with normozoospermic sperm suffering TFF after ICSI and their families were recruited. Firstly, mutations in the PLCZ1 sequence were identified by Whole exome sequencing and validated by Sanger sequencing. Then the transcript and protein levels and locations of PLCZ1/PLCζ in sperms of patients were studied followed by in vitro function analysis and in silico analysis to investigate the function-structure correlation of mutations identified in PLCZ1 through Western blotting, Immunofluorescence, RT-qPCR and Molecular Simulation. Ca2+ oscillations were detected after cRNA microinjection with M⠡ mouse oocyte to investigate the calcium oscillations of abnormal PLCζ. Five variants in compound heterozygosity were identified including five new mutations and three-reported mutations which were located across the main domains of PLCζ, except the EF hands domain. The transcript and protein levels were decreased among all the mutations identified in PLCZ1 at different degrees when transfected with HEK293T cells. Among these mutations, M138V and R391* of PLCζ could not trigger normal Ca2+ oscillations. In case 5, an abnormal location in the head of sperm and a higher expression of PLCζ in the sperm were found.
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Impaired differentiation of megakaryocytes constitutes the principal etiology of thrombocytopenia. The signal transducer and activator of transcription 3 (STAT3) is a crucial transcription factor in regulating megakaryocyte differentiation, yet the precise mechanism of its activation remains unclear. PALLD, an actin-associated protein, has been increasingly recognized for its essential functions in multiple biological processes. This study revealed that megakaryocyte/plateletspecific knockout of PALLD in mice exhibited thrombocytopenia due to diminished platelet biogenesis. In megakaryocytes, PALLD deficiency led to impaired proplatelet formation and polyploidization, ultimately weakening their differentiation for platelet production. Mechanistic studies demonstrated that PALLD bound to STAT3 and interacted with its DNA-binding domain (DBD) and Src homology 2 (SH2) domain via Immunoglobulin domain 3 (Ig3). Moreover, the absence of PALLD attenuated STAT3 Y705 phosphorylation and impeded STAT3 nuclear translocation. Based on the PALLD-STAT3 binding sequence, we designed a peptide C-P3, which can facilitate megakaryocyte differentiation and accelerate platelet production in vivo. In conclusion, this study highlights the pivotal role of PALLD in megakaryocyte differentiation and proposes a novel approach for treating thrombocytopenia by targeting the PALLD-STAT3 interaction.
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Bisphenol A (BPA) is a common component in the manufacture of daily plastic consumer goods. Recent studies have suggested that prenatal exposure to BPA can increase the susceptibility of offspring to mental illness, although the underlying mechanisms remain unclear. In this study, we performed transcriptomic and epigenomic profiling in the adult mouse brain following prenatal exposure to low-dose BPA. We observed a sex-specific transcriptional dysregulation in the cortex, with more significant differentially expressed genes was observed in adult cortex from male offspring. Moreover, the upregulated genes primarily influenced neuronal functions, while the downregulated genes were significantly associated with energy metabolism pathways. More evidence supporting impaired mitochondrial function included a decreased ATP level and a reduced number of mitochondria in the cortical neuron of the BPA group. We further investigated the higher-order chromatin regulatory patterns of DEGs by incorporating published Hi-C data. Interestingly, we found that upregulated genes exhibited more distal interactions with multiple enhancers, while downregulated genes displayed relatively short-range interactions among adjacent genes. Our data further revealed decreased H3K9me3 signal on the distal enhancers of upregulated genes, whereas increased DNA methylation and H3K27me3 signals on the promoters of downregulated genes. In summary, our study provides compelling evidence for the potential health risks associated with prenatal exposure to BPA, and uncovers sex-specific transcriptional changes with a complex interplay of multiple epigenetic mechanisms.
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Compostos Benzidrílicos , Encéfalo , Metilação de DNA , Epigênese Genética , Fenóis , Efeitos Tardios da Exposição Pré-Natal , Animais , Compostos Benzidrílicos/toxicidade , Fenóis/toxicidade , Feminino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Epigênese Genética/efeitos dos fármacos , Masculino , Camundongos , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Camundongos Endogâmicos C57BLRESUMO
Hereditary predisposition play an important role in thrombosis, especially in younger patients. Here we studied a young patient who experienced three different episodes of severe thromboses, some of which were life-threatening (pulmonary artery thrombosis, portal and mesenteric vein thrombosis, and arterial thrombosis of the lower leg). Blood levels of clotting related indicators were assessed. We screened 35 genes linked to thrombosis. We discovered a 756 kb duplication that spanned the F9 gene in region q27.1 of the X chromosome. The repeat includes the full F9 gene, thus, the patient had two functional copies of FIX with the FIX activity 192%. An identical repetition was found in the patient's mother. Both the patient and his mother had high, but variable, plasma FIX activities that promote coagulation. The patient's frequent, severe thrombolic events maybe attributed to the duplication of a big portion of the F9 gene and lupus anticoagulant positive.
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BACKGROUND: Adenoma's detection rates have been reported to vary with the participation status of endoscopic nurses during colonoscopy. This meta-analysis was conducted to determine whether the participation of endoscopy nurses during colonoscopy contributed to the improved detection rate of polyps and adenomas. METHODS: We retrieved English original research from PubMed, Embase, Web of Science, and Cochrane library databases and Chinese original research from the CNKI Data database. We searched for randomized controlled trials (RCTs) comparing the effect of participation of endoscopy nurses during colonoscopy of colorectal polyps and adenomas on polyp detection rates to that of nonparticipation. RevMan5.4 software was used to perform the meta-analysis. RESULTS: This meta-analysis included 11 randomized controlled trials involving 8278 patients. The results showed no significant difference between colonoscopies performed by nurses and endoscopists, but colonoscopies performed by two nurses significantly improved the detection rate of polyps and adenomas. In the random effects model, there was a significant difference in PDR between the single-observation and dual-observation groups (RR, 1.27; 95%CI, 1.05, 1.54; Z = 2.51; P = 0.01). The ADR difference between the single observation group and the double observation group was statistically significant (RR, 1.15; 95%CI, 1.05, 1.26; Z = 2.91; P = 0.004). CONCLUSION: Endoscopy nurses' participation in colonoscopy can improve the detection rate of polyps and adenomas, However, more research is needed to confirm the results.
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Adenoma , Pólipos , Humanos , Adenoma/diagnóstico , Colonoscopia , Bases de Dados Factuais , Ensaios Clínicos Controlados Aleatórios como Assunto , Enfermeiras e EnfermeirosRESUMO
BACKGROUND: Community medical institutions play a vital role in China's healthcare system. While the number of these institutions has increased in recent years, their construction contents remain insufficient. The potential of community medical institutions in preventing, screening, diagnosing, and treating non-communicable chronic diseases (NCDs) has not been fully utilized. This study aims to assess the status of construction contents in community medical institutions in Southwest China and examine how these contents influence the medical choices of NCD patients. METHODS: Descriptive statistics were used to evaluate the construction content of community medical institutions. Multiple-sets of multinomial logistic regression were employed to analyze the associations and marginal impacts between construction content and medical choices. Shapley value analysis was applied to determine the contribution and ranking of these impacts. RESULTS: Descriptive statistics revealed satisfactory construction contents in community medical institutions. Notably, factors such as service attitude, nursing services, expert consultations, charging standards, medical equipment, medical examinations, privacy protection, and referrals significantly influenced medical choices. Among these, service attitude, charging standards, and privacy protection had the most significant marginal improvement effects on NCD patients' choices, with improvements of 12.7%, 10.2%, and 5.9%, respectively. The combined contribution of privacy protection, medical examinations, service attitude, charging standards, and nursing services to medical choices exceeded 80%. CONCLUSION: Optimizing the service contents of community institutions can encourage NCD patients to seek medical care at grassroots hospitals. This study addresses crucial gaps in existing literature and offers practical insights for implementing new medical reform policies, particularly in underdeveloped regions of Southwest China focusing on hierarchical diagnosis and treatment.
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Serviços de Saúde Comunitária , Doenças não Transmissíveis , Humanos , China , Doenças não Transmissíveis/terapia , Feminino , Masculino , Comportamento de Escolha , Pessoa de Meia-Idade , Doença Crônica/terapia , AdultoRESUMO
Parkinson's disease (PD) is inseparable from metabolic disorders but lacks assessment of specific metabolite alteration. To explore the sequential metabolic changes in PD progression, we evenly divided 78 C57BL/6 mice (10 weeks) into six groups (one control group and five experimental groups) and collected the hippocampus tissue of mice after treating with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, and probenecid (twice a week) at five periods (1, 2, 3, 4, and 5 weeks) for metabolome analysis. Our study identified 567 differentially abundant metabolites (DAMs) (total 4348 metabolites). Compared with controls, 145, 146, 171, 208, and 213 DAMs were obtained from the five experimental groups, respectively. Notably, 40 shared DAMs were present in five experimental groups, of which 22 shared DAMs formed a new metabolic network based on amino acid metabolism. Compared with group W3, 84 DAMs were identified in group W5, including 12 unique DAMs. DAMs in different stages of PD were significantly enriched in amino acid metabolism pathway, lipid metabolism pathway, and ferroptosis pathway. l-Glutamine, spermidine, and l-tryptophan were the key hubs in the whole metabolic process of PD. N-Formyl-l-methionine gradually increased in abundance with PD progression, whereas 5-methylcytosine gradually decreased. The study emphasized the sequential changes in DAMs in PD progression, stimulating subsequent studies.
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Aminoácidos , Ferroptose , Metabolômica , Camundongos Endogâmicos C57BL , Doença de Parkinson , Animais , Metabolômica/métodos , Camundongos , Doença de Parkinson/metabolismo , Aminoácidos/metabolismo , Aminoácidos/análise , Masculino , Metaboloma/fisiologia , Hipocampo/metabolismo , Modelos Animais de DoençasRESUMO
PURPOSE: To identify novel variants in ACTL9 and new phenotypes responsible for male infertility. METHODS: Genomic DNA was extracted from peripheral blood samples for whole-exome sequencing (WES). Computer-assisted sperm analysis (CASA) was used to test the motility of spermatozoa. The ultrastructure of flagella and the mitochondrial sheath were assessed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Immunostaining was used to validate the localization and expression of ACTL9 and ACTL7A. An Actl9-mutated mouse model was used to validate the phenotypes by CASA and TEM. RESULTS: We identified novel homozygous variants in ACTL9 in two independent Chinese families. Spermatozoa with ACTL9 mutations showed decreased CASA parameters and a higher proportion of spermatozoa with abnormal morphology, exhibiting coiled flagella and a thickened midpiece. The spermatozoa were characterized by chaotic or irregular '9+2' structures and irregular mitochondrial sheath arrangements in the flagellum. Actl9 knock-in mice also showed abnormal CASA parameters and irregular '9+2' structures in flagella. CONCLUSIONS: Our study expands the mutation spectrum and phenotypic spectrum of ACTL9.
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PURPOSE: The preimplantation genetic testing for aneuploidy (PGT-A) platform is not currently available for small copy-number variants (CNVs), especially those < 1 Mb. Through strategies used in PGT for monogenic disease (PGT-M), this study intended to perform PGT for families with small pathogenic CNVs. METHODS: Couples who carried small pathogenic CNVs and underwent PGT at the Reproductive and Genetic Hospital of CITIC-Xiangya (Hunan, China) between November 2019 and April 2023 were included in this study. Haplotype analysis was performed through two platforms (targeted sequencing and whole-genome arrays) to identify the unaffected embryos, which were subjected to transplantation. Prenatal diagnosis using amniotic fluid was performed during 18-20 weeks of pregnancy. RESULTS: PGT was successfully performed for 20 small CNVs (15 microdeletions and 5 microduplications) in 20 families. These CNVs distributed on chromosomes 1, 2, 6, 7, 13, 15, 16, and X with sizes ranging from 57 to 2120 kb. Three haplotyping-based PGT-M strategies were applied. A total of 89 embryos were identified in 25 PGT cycles for the 20 families. The diagnostic yield was 98.9% (88/89). Nineteen transfers were performed for 17 women, resulting in a 78.9% (15/19) clinical pregnancy rate after each transplantation. Of the nine women who had healthy babies, eight accepted prenatal diagnosis and the results showed no related pathogenic CNVs. CONCLUSION: Our results show that the extended haplotyping-based PGT-M strategy application for small pathogenic CNVs compensated for the insufficient resolution of PGT-A. These three PGT-M strategies could be applied to couples with small pathogenic CNVs.
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Aborto Espontâneo , Diagnóstico Pré-Implantação , Gravidez , Humanos , Feminino , Diagnóstico Pré-Implantação/métodos , Testes Genéticos/métodos , Taxa de Gravidez , Aborto Espontâneo/genética , Nascido Vivo , AneuploidiaRESUMO
'Beta' is a hybrid of Vitis riparia L. and V. labrusca and has a strong ability to adapt to adverse growth environments and is mainly cultivated and used as a resistant rootstock. At present, the most extensively studied MYB TFs are R2R3-type, which have been found to be involved in plant growth, development, and stress response processes. In the present research, VhMYB15, a key transcription factor for abiotic stress tolerance, was screened by bioinformatics in 'Beta' rootstock, and its function under salinity and drought stresses was investigated. VhMYB15 was highly expressed in roots and mature leave under salinity and drought stresses. Observing the phenotype and calculating the survival rate of plants, it was found that VhMYB15-overexpressing plants exhibited relatively less yellowing and wilting of leaves and a higher survival rate under salinity and drought stresses. Consistent with the above results, through the determination of stress-related physiological indicators and the expression analysis of stress-related genes (AtSOS2, AtSOS3, AtSOS1, AtNHX1, AtSnRK2.6, AtNCED3, AtP5CS1, and AtCAT1), it was found that transgenic Arabidopsis showed better stress tolerance and stronger adaptability under salinity and drought stresses. Based on the above data, it was preliminarily indicated that VhMYB15 may be a key factor in salinity and drought regulation networks, enhancing the adaptability of 'Beta' to adverse environments.
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Arabidopsis , Arabidopsis/metabolismo , Resistência à Seca , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Salinidade , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas , Secas , Estresse Fisiológico/genéticaRESUMO
Plants are often exposed to biotic or abiotic stress, which can seriously impede their growth and development. In recent years, researchers have focused especially on the study of plant responses to biotic and abiotic stress. As one of the most widely planted grapevine rootstocks, 'Beta' has been extensively proven to be highly resistant to stress. However, further research is needed to understand the mechanisms of abiotic stress in 'Beta' rootstocks. In this study, we isolated and cloned a novel WRKY transcription factor, VhWRKY44, from the 'Beta' rootstock. Subcellular localization analysis revealed that VhWRKY44 was a nuclear-localized protein. Tissue-specific expression analysis indicated that VhWRKY44 had higher expression levels in grape roots and mature leaves. Further research demonstrated that the expression level of VhWRKY44 in grape roots and mature leaves was highly induced by salt and cold treatment. Compared with the control, Arabidopsis plants overexpressing VhWRKY44 showed stronger resistance to salt and cold stress. The activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were significantly increased, and the contents of proline, malondialdehyde (MDA) and chlorophyll were changed considerably. In addition, significantly higher levels of stress-related genes were detected in the transgenic lines. The results indicated that VhWRKY44 was an important transcription factor in 'Beta' with excellent salt and cold tolerance, providing a new foundation for abiotic stress research.
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Arabidopsis , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Fatores de Transcrição , Vitis , Arabidopsis/genética , Arabidopsis/metabolismo , Vitis/genética , Vitis/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Estresse Fisiológico/genética , Temperatura Baixa , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Tolerância ao Sal/genética , Folhas de Planta/metabolismo , Folhas de Planta/genéticaRESUMO
Chiral molecules have similar physicochemical properties, which are different in terms of physiological activities and toxicities, rendering their differentiation and recognition highly significant. Nanozymes, which are nanomaterials with inherent enzyme-like activities, have garnered significant interest owing to their high cost-effectiveness, enhanced stability, and straightforward synthesis. However, constructing nanozymes with high activity and enantioselectivity remains a significant challenge. This review briefly introduces the synthesis methods of chiral nanozymes and systematically summarizes the latest research progress in enantioselective recognition of chiral molecules based on electrochemical methods and ultraviolet-visible absorption spectroscopy. Moreover, the challenges and development trends in developing enantioselective nanozymes are discussed. It is expected that this review will provide new ideas for the design of multifunctional chiral nanozymes and broaden the application field of nanozymes.
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Técnicas Eletroquímicas , Nanoestruturas , Espectrofotometria Ultravioleta , Estereoisomerismo , Nanoestruturas/químicaRESUMO
Microporous annealed particle (MAP) hydrogels are an attractive platform for engineering biomaterials with controlled heterogeneity. Here, we introduce a microfluidic method to create physicochemical gradients within poly(ethylene glycol) based MAP hydrogels. By combining microfluidic mixing and droplet generator modules, microgels with varying properties were produced by adjusting the relative flow rates between two precursor solutions and collected layer-by-layer in a syringe. Subsequently, the microgels were injected out of the syringe and then annealed with thiol-ene click chemistry. Fluorescence intensity measurements of constructs annealed in vitro and after mock implantation into a tissue defect showed that a continuous gradient profile was achieved and maintained after injection, indicating utility for in situ hydrogel formation. The effects of physicochemical property gradients on human mesenchymal stem cells (hMSCs) were also studied. Microgel stiffness was studied first, and the hMSCs exhibited increased spreading and proliferation as stiffness increased along the gradient. Microgel degradability was also studied, revealing a critical degradability threshold above which the hMSCs spread robustly and below which they were isolated and exhibited reduced spreading. This method of generating spatial gradients in MAP hydrogels could be further used to gain new insights into cell-material interactions, which could be leveraged for tissue engineering applications. A new droplet microfluidic approach to obtain microporous annealed particle hydrogels with physicochemical gradients is presented. Gradient formation is achieved by precisely controlling the mixing of two precursor solutions, and the gradient can be maintained after injection. This approach can be leveraged to produce new materials for tissue repair and to gain unique insights on cell-material interactions.
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[This retracts the article DOI: 10.3892/ol.2019.9978.].
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This article addresses the solution of continuous-time linear Itô stochastic systems with Markovian jumps using an online policy iteration (PI) approach grounded in Q -learning. Initially, a model-dependent offline algorithm, structured according to traditional optimal control strategies, is designed to solve the algebraic Riccati equation (ARE). Employing Lyapunov theory, we rigorously derive the convergence of the offline PI algorithm and the admissibility of the iterative control law through mathematical analysis. This article represents the first attempt to tackle these technical challenges. Subsequently, to address the limitations inherent in the offline algorithm, we introduce a novel online Q -learning algorithm tailored for Itô stochastic systems with Markovian jumps. The proposed Q -learning algorithm obviates the need for transition probabilities and system matrices. We provide a thorough stability analysis of the closed-loop system. Finally, the effectiveness and applicability of the proposed algorithms are demonstrated through a simulation example, underpinned by the theorems established herein.
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Objective: In this article, we investigate how chronic noncommunicable disease (CND) patients evaluate the medical service, and what obstacles exist in this process, which is useful for hospitals to improve efficiency and enhance patient satisfaction. Methods: Based on the total number of CND patients in China, 7 CNDs were selected as the evaluation objects, and then selected the Haodaifu website as the data source, crawled 15,682 medical service reviews, then the 9 themes were analyzed by the LDA theme model. The evaluation index system of six indicators was constructed based on quality management theory. The binary long short-term memory model was used to analyze the sentiment, and the entropy-valued, TOPSIS and gray correlation model was implemented for medical service quality evaluation; the barrier model was used to find out the key factors limiting medical services. Results: (a) Hypertension was rated at a good level in the degree of gray correlation closeness, bronchitis was rated at a low level and the rest were at an intermediate level. (b) The first two overall barriers were the hospitalization process and registration services which occupy about 30%, respectively. This implies that hospitals should focus on providing registration services and inpatient settings in the future. Conclusion: To promote hospitals to provide better services for patients with CNDs and improve patient satisfaction with medical care. And it is necessary to optimize medical services fundamentally by optimizing the inpatient process and improving the registration process to improve efficiency.