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Sugarcane yellow leaf virus (SCYLV) can reduce sugarcane productivity. A novel detection system based on reverse transcription-multienzyme isothermal rapid amplification (RT-MIRA) combined with CRISPR-Cas12a, named RT-MIRA-CRISPR-Cas12a, was developed. This innovative approach employs crude leaf extract directly as the reaction template, streamlining the extraction process for simplicity and speed. Combining RT-MIRA and CRISPR-Cas12a in one reaction tube increases the ease of operation while reducing the risk of aerosol contamination. In addition, it exhibits sensitivity equivalent to qPCR, boasting a lower detection limit of 25 copies. Remarkably, the entire process, from sample extraction to reaction completion, requires only 52-57 minutes, just a thermostat water bath. The result can be observed and judged by the naked eye.IMPORTANCESugarcane yellow leaf disease (SCYLD) is an important viral disease that affects sugarcane yield. There is an urgent need for rapid, sensitive, and stable detection methods. The reverse transcription-multienzyme isothermal rapid amplification combined with CRISPR-Cas12a (RT-MIRA-CRISPR-Cas12a) method established in this study has good specificity and high sensitivity. In addition, the system showed good compatibility and stability with the crude leaf extract, as shown by the fact that the crude extract of the positive sample could still be stably detected after 1 week when placed at 4°C. RT-MIRA-CRISPR-Cas12a, reverse transcription polymerase chain reaction (RT-PCR), and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to detect SCYLV on 33 sugarcane leaf samples collected from the field, and it was found that the three methods reached consistent conclusions. This Cas12a-based detection method proves highly suitable for the rapid on-site detection of the SCYLV.
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Cell-based microarrays are widely used in the fields of drug discovery and toxicology. Precise gradient generation and automated drug feeding are essential for high-throughput screening of live cells in tiny droplets. However, most existing technologies either require sophisticated robotic equipment or cause mechanical/physiological interference with cells. Here, a heterogeneous organohydrogel is presented for automated gradient drug feeding, while ensuring minimal interference with cells. The heterogeneous organohydrogel comprises three crucial components. The bottom surface can automatically generate gradients functioning as a gradient generator, the organohydrogel bulk allows unidirectional transport of drugs without backflow, and the top surface with hydrophilic arrays can firmly anchor the cell-based droplet array to evaluate the concentration-dependent bioeffects of drugs accurately. Such a unique structure enables universal screening of different cell types and drugs dissolved in different solvents, requiring neither additional accessories nor arduous drug functionalization. The heterogeneous organohydrogel with unprecedented automation and non-interference possesses the enormous potential to be a next-generation platform for drug screening.
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BACKGROUND: Due to regional and cultural differences, the current status of extremely preterm infants(EPIs) treatment across different areas of mainland China remains unclear. This study investigated the survival rate and incidence of major diseases among EPIs in the southwest area of Fujian province. METHOD: This retrospective and multicenter study collected perinatal data from EPIs with gestational ages between 22-27+ 6w and born in the southwest area of Fujian province. The study population was divided into 6 groups based on gestational age at delivery. The primary outcome was the survival status at ordered hospital discharge or correct gestational age of 40 weeks, and the secondary outcome was the incidence of major diseases. The study analyzed the actual survival status of EPIs in the area. RESULT: A total of 2004 preterm infants with gestational ages of 22-27+ 6 weeks were enrolled in this study. Among them, 1535 cases (76.6%) were born in the delivery room but did not survive, 469 cases (23.4%) were transferred to the neonatal department for treatment, 101 cases (5.0%) received partial treatment, and 368 cases (18.4%) received complete treatment. The overall all-cause mortality rate was 84.4% (1691/2004). The survival rate and survival rate without major serious disease for EPIs who received complete treatment were 85.1% (313/368) and 31.5% (116/318), respectively. The survival rates for gestational ages 22-22+ 6w, 23-23+ 6w, 24-24+ 6w, 25-25+ 6w, 26-26+ 6w, and 27-27+ 6w were 0%, 0%, 59.1% (13/22), 83% (39/47), 88.8% (87/98), and 89.7% (174/198), respectively. The survival rates without major serious disease were 0%, 0%, 9.1% (2/22), 19.1% (9/47), 27.6% (27/98), and 40.2% (78/194), respectively. CONCLUSION: The all-cause mortality of EPIs in the southwest area of Fujian Province remains high, with a significant number of infants were given up after birth in the delivery room being the main influencing factor. The survival rate of EPIs who received complete treatment at 25-27 weeks in the NICU was similar to that in developed countries. However, the survival rate without major serious disease was significantly lower compared to high-income countries.
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Idade Gestacional , Lactente Extremamente Prematuro , Doenças do Prematuro , Humanos , China/epidemiologia , Estudos Retrospectivos , Recém-Nascido , Feminino , Masculino , Doenças do Prematuro/epidemiologia , Doenças do Prematuro/mortalidade , Doenças do Prematuro/terapia , Taxa de Sobrevida , Incidência , Mortalidade InfantilRESUMO
Metastatic rhabdomyosarcoma is associated with poor survival and unsatisfactory treatment outcomes. Therefore, new immunotherapeutic methods are urgently required. Fibroblast growth factor receptor 4 (FGFR4), a new therapeutic target for rhabdomyosarcoma, plays a crucial role in its onset and development. This study aimed to generate FGFR4 single-chain variable fragment-based chimeric antigen receptor (CAR) T cells without causing evident toxicity and incorporating an inducible caspase-9 (iCasp9) suicide gene system to enhance their safety. FGFR4 antigen expression was evaluated in normal murine tissues, normal human tissues, and specimens from patients with rhabdomyosarcoma. Combined with a 4-1BB co-stimulatory domain, a CD3ζ signaling domain, and an iCasp9 suicide gene, CAR-T cells with an FGFR4-specific single-chain variable fragment were developed. The specific cytotoxic effects, T-cell proliferation, cytokine secretion, apoptosis induction by chemical dimerization (AP20187), and toxicity of FGFR4 CAR-T cells were investigated in vitro and in vivo. FGFR4 CAR-T cells generated a variety of immune-promoting cytokines, including tumor necrosis factor α, interleukin 2, and interferon γ, and displayed effective cytotoxic activity against FGFR4-overexpressing rhabdomyosarcoma cells in vitro. FGFR4 CAR-T cells were relatively effective against FGFR4-overexpressing rhabdomyosarcoma, with tumor regression and poor survival in a subcutaneous xenograft model. The iCasp9 gene was incorporated into FGFR4 CAR-T cells and it was demonstrated that effective and reliable suicide gene activity depends on the administration of AP20187. By making use of the cross-reaction of FGFR4 CAR-T cells with murine FGFR4 in a syngeneic tumor model, this study found that FGFR4 CAR-T cells could regulate the growth of tumors without evident toxicity. Our study demonstrates that FGFR4 is a prospective target for CAR-T cell therapy in rhabdomyosarcoma without serious on-target off-tumor toxicity. FGFR4 CAR-T cells with the iCasp9 suicide gene system as a safety switch to limit toxicity may broaden the clinical applications of cellular therapy.
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Background: Wuwei Xiaodu Drink (WWXDD), a classical decoction of traditional Chinese medicine, has been clinically used for the treatment of gout in China for many years. This study aimed to demonstrate the efficacy of WWXDD in treating gout flares and elucidate its underlying therapeutic mechanism. Methods: A randomized control trial was conducted to compare the effectiveness of WWXDD with low-dose colchicine in gout arthritis. The primary outcome was the clinical response rate on the 7th day, and joint syndrome score and serological tests were secondary outcome measures and were compared in the two groups on the 1st and 7th day. Then we used a network pharmacology approach to investigate the possible mechanism of WWXDD in treating gout, and the effects of WWXDD on the MSU-induced rat model were observed. Results: In the clinical trial, a total of 78 participants completed the study, and the results demonstrated comparable clinical complete response rates, joint symptom scores, and serological test outcomes between the two groups on the 7th day. Network pharmacology analysis identified 51 core genes that target gout and WWXDD interactions. Notably, strong significant correlations were observed with inflammation cytokine genes and metabolism-related genes. Furthermore, it was found that WWXDD reduced gene expression levels of inflammation cytokines including IL-1ß, TNF, and IL-18 in an MSU-induced rat model while increasing IL-10 expression. Additionally, WWXDD decreased insulin gene expression in this model. Moreover, WWXDD exhibited a reduction in both gene and protein expressions associated with the NLRP3-mediated inflammatory pathway in inflamed joints of rats. Conclusion: The results of the present study suggested the anti-inflammatory effects of WWXDD in the treatment of gouty arthritis, partially through inhibiting NLRP3 inflammasome activation. Clinical Trial Registration: ClinicalTrials.gov, identifier ChiCTR2100047807.
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Herein, the micro-porous polylactic acid coating applied on the surface of the cylindrical substrate is fabricated by a novel in situ pore-formation strategy based on the combinational effect of breath figure (BF) and vapor-induced phase separation (VIPS) processes. Under the condition of high environmental humidity, solvent pair of chloroform and dimethylformamide is employed for post-treatment onto pre-formed PLA coating to induce the pore-formation following the mechanism of BF and VIPS, respectively. A composite porous structure with both cellular-like and bi-continuous network morphologies is obtained. By tunning the experimental factors including the ratio of the solvent pair, environmental humidity, and temperature, morphological manipulation upon the pore morphology can be facilely achieved based on the control of mechanism transition between BF and VIPS. Paclitaxel is used as a model drug and loaded into the porous coating by the wicking effect of post-immersion. Coatings with different morphological features show varying drug loading and release capacities. The 28-day release test reveals dynamic release profiles between different coating samples, with the total release rate ranging from 35.70% to 79.96%. Optimal loading capacity of 19.28 µg cm-2 and 28-day release rate of 35.70% are achieved for the coating with composite BF-VIPS structure. This research established a cost-efficient strategy with high flexibility in the structural manipulation concerning the construction of drug-eluting coating with the feature of manipulative drug delivery.
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BACKGROUND: N1-Methyladenosine (m1A) is an abundant modification of transcripts regulating mRNA structure and translation efficiency. However, the characteristics and biological functions of mRNA m1A modification in adult hippocampal neurogenesis remain enigmatic. RESULTS: We found that m1A demethylase Alkbh3 was dramatically enriched in neurons and neuronal genesis. Functionally, depletion of Alkbh3 in neural stem cells (NSCs) significantly decreased m1A modification, neuronal differentiation and proliferation coupling with increasing gliogenesis, whereas overexpressing Alkbh3 facilitated neuronal differentiation and proliferation. Mechanistically, the m1A demethylation of Mmp15 mRNA by Alkbh3 improved its RNA stability and translational efficacy, which promoted neurogenesis. Therapeutically, the silencing of Alkbh3 reduced hippocampal neurogenesis and impaired spatial memory in the adult mice. CONCLUSIONS: We reveal a novel function of m1A demethylation on Mmp15 mRNA in Alkbh3-mediated neurogenesis, which shed light on advancing Alkbh3 regulation of neurogenesis as a novel neurotherapeutic strategy.
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Circular RNAs (circRNAs) are a new group of endogenous RNAs recently found to be involved in the development of various diseases, including their confirmed involvement in the progression of several types of cancers. Unluckily, the abnormal expression and functions of circRNAs in breast cancer shall be further investigated. This work aims to elucidate the action and molecular mechanism of circHSDL2 in the malignant progression of breast cancer. Differential expression profiles of circRNAs in breast cancer tissues relative to normal breast tissues and in the exosomes of breast cancer patients compared to healthy women were analyzed from databases to identify potentially functional circRNAs. CircHSDL2 was selected for further investigation. Cell proliferation, migration and invasion assays were done to assess the effect of circHSDL2 overexpression on breast cancer cells. Bioinformatics test and dual-luciferase reporter experiments were done to explore the interaction between circHSDL2 and miRNA. Downstream target genes were further investigated through proteomics analysis and Western blotting. The influence of circHSDL2 on breast cancer in vivo was evaluated through xenograft experiments in nude mice. Functional analysis demonstrated circHSDL2 overexpression promoted the division, movement, and invasion of breast cancer cells both in vivo and in vitro. Mechanistically, circHSDL2 acted as a sponge for miR-7978 to affect ZNF704 expression and thereby regulate the Hippo pathway in breast cancer cells. In conclusion, circHSDL2 regulates the Hippo pathway through the miR-7978/ZNF704 axis to facilitate the malignancy of breast cancer. This may be a potential biomarker and treatment target.
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Neoplasias da Mama , Proliferação de Células , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Via de Sinalização Hippo , MicroRNAs , Proteínas Serina-Treonina Quinases , RNA Circular , Transdução de Sinais , Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Camundongos Nus , MicroRNAs/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA Circular/genética , Transdução de Sinais/genéticaRESUMO
BACKGROUND: Granulomatosis with polyangiitis (GPA) is one of the most prevalent forms of the antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. GPA is characterized histologically by necrotizing granulomatous inflammation in addition to vasculitis. The diagnosis of GPA depends on clinical presentation, serological evidence of a positive ANCA, and/or histological evidence of necrotizing vasculitis or granulomatous destructive parenchymal inflammation. Cytoplasmic ANCA (c-ANCA) is positive in 65%-75% of GPA patients, accompanied by proteinase 3 (PR3), the main target antigen of c-ANCA, another 5% of GPA patients had negative ANCA. CASE SUMMARY: The patient, a 52-year-old male, presented with unexplained nasal congestion, tinnitus, and hearing loss. After a duration of 4 months experiencing these symptoms, the patient subsequently developed fever and headache. The imaging examination revealed the presence of bilateral auricular mastoiditis and partial paranasal sinusitis, and the ANCA results were negative. The anti-infective therapy proved to be ineffective, but the patient's symptoms and fever were quickly relieved after 1 wk of treatment with methylprednisolone 40 mg once a day. However, after continuous use of methylprednisolone tablets for 3 months, the patient experienced a recurrence of fever accompanied by right-sided migraine, positive c-ANCA and PR3, and increased total protein in cerebrospinal fluid. The patient was diagnosed with GPA. After receiving a treatment regimen of intravenous methylprednisolone 40 mg/d and cyclophosphamide 0.8 g monthly, the patient experienced alleviation of fever and headache. Additionally, the ANCA levels became negative and there has been no recurrence. CONCLUSION: For GPA patients with negative ANCA, there is a potential for early missed diagnosis. The integration of histopathological results and multidisciplinary communication plays a crucial role in facilitating ANCA-negative GPA.
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Immunotherapy for hematological malignancies is a rapidly advancing field that has gained momentum in recent years, primarily encompassing chimeric antigen receptor T-cell (CAR-T) therapies, immune checkpoint inhibitors, and other modalities. However, its clinical efficacy remains limited, and drug resistance poses a significant challenge. Therefore, novel immunotherapeutic targets and agents need to be identified. Recently, N6-methyladenosine (m6A), the most prevalent RNA epitope modification, has emerged as a pivotal factor in various malignancies. Reportedly, m6A mutations influence the immunological microenvironment of hematological malignancies, leading to immune evasion and compromising the anti-tumor immune response in hematological malignancies. In this review, we comprehensively summarize the roles of the currently identified m6A modifications in various hematological malignancies, with a particular focus on their impact on the immune microenvironment. Additionally, we provide an overview of the research progress made in developing m6A-targeted drugs for hematological tumor therapy, to offer novel clinical insights.
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Adenosina , Neoplasias Hematológicas , Microambiente Tumoral , Humanos , Microambiente Tumoral/imunologia , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/terapia , Adenosina/análogos & derivados , Adenosina/imunologia , Adenosina/metabolismo , Animais , Imunoterapia/métodosRESUMO
RNA interference (RNAi) technology is widely used in the biological prevention and control of terrestrial insects. One of the main factors with the application of RNAi in insects is the difference in RNAi efficiency, which may vary not only in different insects, but also in different genes of the same insect, and even in different double-stranded RNAs (dsRNAs) of the same gene. This work focuses on the last question and establishes a bioinformatics software that can help researchers screen for the most efficient dsRNA targeting target genes. Among insects, the red flour beetle (Tribolium castaneum) is known to be one of the most sensitive to RNAi. From iBeetle-Base, we extracted 12 027 efficient dsRNA sequences with a lethality rate of ≥20% or with experimentation-induced phenotypic changes and processed these data to correspond to specific silence efficiency. Based on the first complied novel benchmark dataset, we specifically designed a deep neural network to identify and characterize efficient dsRNA for RNAi in insects. The dna2vec word embedding model was trained to extract distributed feature representations, and three powerful modules, namely convolutional neural network, bidirectional long short-term memory network, and self-attention mechanism, were integrated to form our predictor model to characterize the extracted dsRNAs and their silencing efficiencies for T. castaneum. Our model dsRNAPredictor showed reliable performance in multiple independent tests based on different species, including both T. castaneum and Aedes aegypti. This indicates that dsRNAPredictor can facilitate prescreening for designing high-efficiency dsRNA targeting target genes of insects in advance.
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Accumulating evidence indicates that plasma metal levels may be associated with Type 2 diabetes mellitus (T2DM) incident risk. Mitochondrial function such as mitochondrial DNA copy number (mtDNA-CN) might be linked to metal exposure and physiological metabolism. Mediation analysis was conducted to determine the mediating roles of mtDNA-CN in the association between plasma metals and diabetes risk. In the present study, we investigated associations between plasma metals levels, mtDNA-CN, and T2DM incident in the elderly population with a 6-year follow-up (two times) study. Ten plasma metals [i.e. manganese, aluminum, calcium, iron, barium (Ba), arsenic, copper, selenium, titanium, and strontium] were measured using inductively coupled plasma mass spectrometry. mtDNA-CN was measured by real-time polymerase chain reaction. Multivariable linear regression and logistic regression analyses were carried out to estimate the relationship between plasma metal concentrations, mtDNA-CN, and T2DM incident risk in the current work. Plasma Ba deficiency and mtDNA-CN decline were associated with T2DM incident risk during the aging process. Meanwhile, plasma Ba was found to be positively associated with mtDNA-CN. Mitochondrial function mtDNA-CN demonstrated mediating effects in the association between plasma Ba deficiency and T2DM incident risk, and 49.8% of the association was mediated by mtDNA-CN. These findings extend the knowledge of T2DM incident risk factors and highlight the point that mtDNA-CN may be linked to plasma metal elements and T2DM incident risk.
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Bário , Variações do Número de Cópias de DNA , DNA Mitocondrial , Diabetes Mellitus Tipo 2 , Humanos , DNA Mitocondrial/genética , DNA Mitocondrial/sangue , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/sangue , Masculino , Feminino , Idoso , Seguimentos , Bário/sangue , Fatores de Risco , Pessoa de Meia-Idade , IncidênciaRESUMO
The replacement of a CC unit with an isoelectronic BN unit in aromatic systems can give rise to molecules and materials with fascinating properties. We report here the synthesis, characterization, and reactivity of a 1,4,2,3-diazadiborole species, 2, featuring an unprecedented 6π-aromatic BN-heterocyclic moiety that is isoelectronic to cyclopentadienide (Cp-). Bearing an unsymmetrical B=B entity, 2 exhibits reactivity toward oxidants, protic reagents, electrophiles, and unsaturated substrates. This reactivity facilitates the synthesis of a variety of novel mono- and bicyclic organoboron derivatives through mechanisms including ring retention, cleavage/recombination, annulation, and expansion. These findings reveal innovative synthetic routes to BN-embedded aromatic compounds via desymmetrization, affording unique building blocks for synthetic chemistry.
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Serum magnesium levels exceeding 0.9 mmol/L are associated with increased survival rates in patients with CKD. This retrospective study aimed to identify risk factors for cardio-cerebrovascular events among patients receiving continuous ambulatory peritoneal dialysis (CAPD) and to examine their correlations with serum magnesium levels. Sociodemographic data, clinical physiological and biochemical indexes, and cardio-cerebrovascular event data were collected from 189 patients undergoing CAPD. Risk factors associated with cardio-cerebrovascular events were identified by univariate binary logistic regression analysis. Correlations between the risk factors and serum magnesium levels were determined by correlation analysis. Univariate regression analysis identified age, C-reactive protein (CRP), red cell volume distribution width standard deviation, red cell volume distribution width corpuscular volume, serum albumin, serum potassium, serum sodium, serum chlorine, serum magnesium, and serum uric acid as risk factors for cardio-cerebrovascular events. Among them, serum magnesium ≤0.8 mmol/L had the highest odds ratio (3.996). Multivariate regression analysis revealed that serum magnesium was an independent risk factor, while serum UA (<440 µmol/L) was an independent protective factor for cardio-cerebrovascular events. The incidence of cardio-cerebrovascular events differed significantly among patients with different grades of serum magnesium (χ2 = 12.023, p = 0.002), with the highest incidence observed in patients with a serum magnesium concentration <0.8 mmol/L. High serum magnesium levels were correlated with high levels of serum albumin (r = 0.399, p < 0.001), serum potassium (r = 0.423, p < 0.001), and serum uric acid (r = 0.411, p < 0.001), and low levels of CRP (r = -0.279, p < 0.001). In conclusion, low serum magnesium may predict cardio-cerebrovascular events in patients receiving CAPD.
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Magnésio , Diálise Peritoneal Ambulatorial Contínua , Humanos , Masculino , Feminino , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Pessoa de Meia-Idade , Magnésio/sangue , Estudos Retrospectivos , Fatores de Risco , Adulto , Idoso , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Incidência , Transtornos Cerebrovasculares/etiologia , Transtornos Cerebrovasculares/sangue , Transtornos Cerebrovasculares/epidemiologia , Modelos Logísticos , Proteína C-Reativa/análise , Ácido Úrico/sangue , Falência Renal Crônica/terapia , Falência Renal Crônica/sangueRESUMO
Asthma is a heterogeneous disease characterized by chronic airway inflammation, reversible airflow limitation, and airway remodeling. Eosinophil peroxidase (EPX) is the most abundant secondary granule protein unique to activated eosinophils. In this study, we aimed to illustrate the effect of EPX on the epithelial-mesenchymal transition (EMT) in BEAS-2B cells. Our research found that both EPX and ADAM33 were negatively correlated with FEV1/FVC and FEV1%pred, and positively correlated with IL-5 levels. Asthma patients had relatively higher levels of ADAM33 and EPX compared to the healthy control group. The expression of TSLP, TGF-ß1 and ADAM33 in the EPX intervention group was significantly higher. Moreover, EPX could promote the proliferation, migration and EMT of BEAS-2B cells, and the effect of EPX on various factors was significantly improved by the PI3K inhibitor LY294002. The findings from this study could potentially offer a novel therapeutic target for addressing airway remodeling in bronchial asthma, particularly focusing on EMT.
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Remodelação das Vias Aéreas , Asma , Brônquios , Peroxidase de Eosinófilo , Células Epiteliais , Transição Epitelial-Mesenquimal , Fator de Crescimento Transformador beta1 , Humanos , Asma/metabolismo , Asma/patologia , Asma/fisiopatologia , Asma/imunologia , Masculino , Feminino , Células Epiteliais/metabolismo , Peroxidase de Eosinófilo/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Pessoa de Meia-Idade , Adulto , Brônquios/patologia , Interleucina-5/metabolismo , Cromonas/farmacologia , Citocinas/metabolismo , Linhagem Celular , Linfopoietina do Estroma do Timo , Proliferação de Células , Movimento Celular , Morfolinas/farmacologia , Proteínas ADAMRESUMO
Nickel-catalyzed transannulation reactions triggered by the extrusion of small gaseous molecules have emerged as a powerful strategy for the efficient construction of heterocyclic compounds. However, their use in asymmetric synthesis remains challenging because of the difficulty in controlling stereo- and regioselectivity. Herein, we report the first nickel-catalyzed asymmetric synthesis of N-N atropisomers by the denitrogenative transannulation of benzotriazones with alkynes. A broad range of N-N atropisomers was obtained with excellent regio- and enantioselectivity under mild conditions. Moreover, density functional theory (DFT) calculations provided insights into the nickel-catalyzed reaction mechanism and enantioselectivity control.
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As important π-skeletons, benzosiloles often possess unique electronic and optical properties and have been widely used in semiconductor materials. Therefore, great attention has been drawn to the area of developing novel synthetic methods for various benzosiloles. However, the synthesis of enantioenriched silicon-stereogenic benzosiloles is still at an early stage and remains to be explored. Herein, we performed systematic density functional theory studies on the recently reported nickel-catalyzed asymmetric synthesis of silicon-stereogenic benosiloles, which was enabled by an enantioselective desymmetrization of (2-alkenyl)aryl-substituted silacyclobutanes. Our computational study shows that the reaction mechanism involves ligand exchange, oxidative addition, alkene insertion, and hydrogen-transfer coupled reductive-demetalation steps. The proposed transmetalation and ß-hydride elimination mechanism was not found, which might be due to the unfavorable ring strain of the multicyclic intermediates. The novel hydrogen-transfer coupled reductive-demetalation mechanism was shown to be reasonable for the generation of the silicon-stereogenic benzosilole. Noncovalent interactions (including C-H···π and hydrogen bonding) in the rate-determining alkene insertion transition state account for the origins of the enantioselectivity. Our computational study sheds light on the detailed reaction mechanism and also provides insights for the development of novel approaches for synthesis of high-value silicon-stereogenic compounds.
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INTRODUCTION: The study presented here aimed to establish a predictive model for heart failure (HF) and all-cause mortality in peritoneal dialysis (PD) patients with machine learning (ML) algorithm. METHODS: We retrospectively included 1006 patients who initiated PD from 2010 to 2016. XGBoost, random forest (RF), and AdaBoost were used to train models for assessing risk for 1-year and 5-year HF hospitalization and mortality. The performance was validated using fivefold cross-validation. The optimal ML algorithm was used to construct the models to predictive the risk of the HF and all-cause mortality. The prediction performance of ML methods and Cox regression was compared. RESULTS: Over a median follow-up of 49 months. Two hundred and ninety-eight patients developed HF required hospitalization; 199 patients died during the follow-up. The RF model (AUC = 0.853) was the best performing model for predicting HF, and the XGBoost model (AUC = 0.871) was the best model for predicting mortality. Baseline moderate or severe renal disease, systolic blood pressure (SBP), body mass index (BMI), age, Charlson Comorbidity Index (CCI) score were strongly associated with HF hospitalization, whereas age, CCI score, creatinine, age, high-density lipoprotein cholesterol (HDL-C), total cholesterol, baseline estimated glomerular filtration rate (eGFR) were the most significant predictors of mortality. For all the above endpoints, the ML models demonstrated better discrimination than Cox regression. CONCLUSIONS: We developed and validated a novel method to predict the risk factors of HF and all-cause mortality that integrates readily available clinical, laboratory, and electrocardiographic variables to predict the risk of HF among PD patients.
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Insuficiência Cardíaca , Diálise Peritoneal , Humanos , Nomogramas , Estudos Retrospectivos , Medição de Risco/métodos , Hospitalização , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/etiologia , Diálise Peritoneal/efeitos adversos , Aprendizado de Máquina , ColesterolRESUMO
Copine proteins are highly conserved and ubiquitously found in eukaryotes, and their indispensable roles in different species were proposed. However, their exact function remains unclear. The phytohormone brassinosteroids (BRs) play vital roles in plant growth, development and environmental responses. A key event in effective BR signaling is the formation of functional BRI1-SERK receptor complex and subsequent transphosphorylation upon ligand binding. Here, we demonstrate that BONZAI (BON) proteins, which are plasma membrane-associated copine proteins, are critical components of BR signaling in both the monocot maize and the dicot Arabidopsis. Biochemical and molecular analyses reveal that BON proteins directly interact with SERK kinases, thereby ensuring effective BRI1-SERK interaction and transphosphorylation. This study advances the knowledge on BR signaling and provides an important target for optimizing valuable agronomic traits, it also opens a way to study steroid hormone signaling and copine proteins of eukaryotes in a broader perspective.
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Proteínas de Arabidopsis , Arabidopsis , Proteínas de Transporte , Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Zea mays/genética , Zea mays/metabolismo , Proteínas Quinases/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Membrana/metabolismoRESUMO
Systemic lupus erythematosus (SLE) is a multi-organ and systemic autoimmune disease characterized by an imbalance of humoral and cellular immunity. The efficacy and side effects of traditional glucocorticoid and immunosuppressant therapy remain controversial. Recent studies have revealed abnormalities in mesenchymal stem cells (MSCs) in SLE, leading to the application of bone marrow-derived MSCs (BM-MSCs) transplantation technique for SLE treatment. However, autologous transplantation using BM-MSCs from SLE patients has shown suboptimal efficacy due to their dysfunction, while allogeneic mesenchymal stem cell transplantation (MSCT) still faces challenges, such as donor degeneration, genetic instability, and immune rejection. Therefore, exploring new sources of stem cells is crucial for overcoming these limitations in clinical applications. Human amniotic epithelial stem cells (hAESCs), derived from the eighth-day blastocyst, possess strong characteristics including good differentiation potential, immune tolerance with low antigen-presenting ability, and unique immune properties. Hence, hAESCs hold great promise for the treatment of not only SLE but also other autoimmune diseases.