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PURPOSE: Radiotherapy (RT) is the primary treatment for prostate cancer (PCa); however, the emergence of castration-resistant prostate cancer (CRPC) often leads to treatment failure and cancer-related deaths. In this study, we aimed to explore the use of microwave hyperthermia (MW-HT) to sensitize PCa to RT and investigate the underlying molecular mechanisms. METHODS: We developed a dedicated MW-HT heating setup, created an in vitro and in vivo MW-HT + RT treatment model for CRPC. We evaluated PC3 cell proliferation using CCK-8, colony experiments, DAPI staining, comet assay and ROS detection method. We also monitored nude mouse models of PCa during treatment, measured tumor weight, and calculated the tumor inhibition rate. Western blotting was used to detect DNA damage repair protein expression in PC3 cells and transplanted tumors. RESULTS: Compared to control, PC3 cell survival and clone formation rates decreased in RT + MW-HT group, demonstrating significant increase in apoptosis, ROS levels, and DNA damage. Lower tumor volumes and weights were observed in treatment groups. Ki-67 expression level was reduced in all treatment groups, with significant decrease in RT + MW-HT groups. The most significant apoptosis induction was confirmed in RT + MW-HT group by TUNEL staining. Protein expression levels of DNA-PKcs, ATM, ATR, and P53/P21 signaling pathways significantly decreased in RT + MW-HT groups. CONCLUSION: MW-HT + RT treatment significantly inhibited DNA damage repair by downregulating DNA-PKcs, ATM, ATR, and P53/P21 signaling pathways, leading to increased ROS levels, aggravate DNA damage, apoptosis, and necrosis in PC3 cells, a well-established model of CRPC.
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Adenocarcinoma , Hipertermia Induzida , Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Humanos , Masculino , Animais , Camundongos , Neoplasias de Próstata Resistentes à Castração/radioterapia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Células PC-3 , Espécies Reativas de Oxigênio/metabolismo , Micro-Ondas , Proteína Supressora de Tumor p53/metabolismo , Hipertermia Induzida/métodos , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/metabolismo , Reparo do DNA , Apoptose , Estresse Oxidativo , Hipertermia , Adenocarcinoma/radioterapia , DNA/metabolismo , Linhagem Celular Tumoral , Proliferação de CélulasRESUMO
BACKGROUND: Postoperative pain after orthognathic surgery is commonly managed with opioids, which can cause nausea and vomiting. PURPOSE: The purpose of this study was to determine whether regional nerve blocks during bimaxillary surgery reduced postoperative pain and vomiting compared with patient-controlled analgesia (PCA). STUDY DESIGN, SETTING, AND SAMPLE: This retrospective cohort study recruited patients who underwent bimaxillary surgery between August 2018 and September 2020 at the Fourth Military Medical University Hospital. Participants whose procedures involved the cheekbone, temporomandibular joint, mandibular angle, or an autogenous iliac bone graft and those who were admitted to the intensive care unit after surgery were excluded. PREDICTOR VARIABLES: The primary predictor variables were postoperative analgesia management, regional maxillary and inferior alveolar nerve blocks, and PCA. OUTCOME VARIABLES: The primary outcome variables were moderate-to-severe postoperative pain and postoperative vomiting (POV) during the first 24 hours. Moderate-to-severe pain was defined as pain numerical rating scale ≥4, POV was defined as vomiting of gastrointestinal contents. COVARIATES: The study covariates included demographic, surgical, and anesthesia characteristics. ANALYSES: Statistical analyses were conducted using an unpaired t-test, χ2 test, or Fisher's exact test for the bivariate analysis. A multivariate logistic regression analysis was performed to assess the associations between the primary predictor variables and outcomes. Statistical significance was set at P < .05. RESULTS: 354 participants were included in the study (262 in the nerve block group, mean age 22.5 ± 4.0 years; 92 in the PCA group, mean age 22.6 ± 4.4 years; P = .81). There was no significant difference in sex between the groups (63.4 and 55.4% females in nerve block and PCA groups, respectively, P = .18). The multivariate regression analyses demonstrated that nerve blocks did not decrease moderate-to-severe postoperative pain (7.6 vs 10.9%, adjusted odds ratio = 0.67, 95% confidence interval: 0.22-2.01, P = .48), although they were associated with decreased POV (38.5 vs 65.2%, adjusted odds ratio = 0.34, 95% confidence interval: 0.18-0.65, P = .001). CONCLUSION AND RELEVANCE: For bimaxillary surgery, regional nerve blocks as opioid-free postoperative analgesia were not significantly associated with decreased postoperative pain but were associated with a low POV risk.
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OBJECTIVE: Signal transduction and transcriptional activator 5A (STAT5A), which has been reported to be frequently phosphorylated in tumors, plays pivotal roles in tumor progression. However, the role of STAT5A in gastric cancer (GC) progression and the downstream targets of STAT5A remain largely unknown. METHODS: The expression of STAT5A and CD44 were assessed. GC cells were treated with altered STAT5A and CD44 to evaluate their biological functions. Nude mice were given injections of genetically manipulated GC cells and growth of xenograft tumors and metastases was measured. RESULTS: The increased level of p-STAT5A is associated with tumor invasion and poor prognosis in GC. STAT5A promoted GC cell proliferation by upregulating CD44 expression. STAT5A directly binds to the CD44 promoter and promotes its transcription. CONCLUSIONS: The STAT5A/CD44 pathway plays a critical role in GC progression, promising potential clinical applications for improving treatment of GC.
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Neoplasias Gástricas , Animais , Camundongos , Humanos , Neoplasias Gástricas/genética , Regulação para Cima , Camundongos Nus , Fatores de Transcrição/metabolismo , Transdução de Sinais , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Proteínas Supressoras de Tumor/genética , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/metabolismoRESUMO
Neuroblastoma (NB) is one of the highly vascularized childhood solid tumors, and understanding the molecular mechanisms underlying angiogenesis in NB is crucial for developing effective therapeutic strategies. B-cell receptor-associated protein 31 (BAP31) has been implicated in tumor progression, but its role in angiogenesis remains unexplored. This study investigated BAP31 modulation of pro-angiogenic factors in SH-SY5Y NB cells. Through protein overexpression, knockdown, antibody blocking, and quantification experiments, we demonstrated that overexpression of BAP31 led to increased levels of vascular endothelial growth factor A (VEGFA) and Galectin-3 (GAL-3), which are known to promote angiogenesis. Conditioned medium derived from BAP31-overexpressing neuroblastoma cells stimulated migration and tube formation in endothelial cells, indicating its pro-angiogenic properties. Also, we demonstrated that BAP31 enhances capillary tube formation by regulating hypoxia-inducible factor 1 alpha (HIF-1α) and its downstream target, GAL-3. Furthermore, GAL-3 downstream proteins, Jagged 1 and VEGF receptor 2 (VEGFR2), were up-regulated, and blocking GAL-3 partially inhibited the BAP31-induced tube formation. These findings suggest that BAP31 promotes angiogenesis in NB by modulating GAL-3 and VEGF signaling, thereby shaping the tumor microenvironment. This study provides novel insights into the pro-angiogenic role of BAP31 in NB.
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Neuroblastoma , Fator A de Crescimento do Endotélio Vascular , Criança , Humanos , Angiogênese , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Galectina 3/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neovascularização Patológica/patologia , Neuroblastoma/metabolismo , Microambiente Tumoral , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Tissue cells in epithelial or endothelial monolayers are connected through cell-cell junctions, which are stabilized by transmembrane E-cadherin bonds and intracellular actin filaments. These bonds and junctions play a crucial role in maintaining the barrier function of epithelia and endothelia and are believed to transmit forces between cells. Additionally, E-cadherin bonds can impact the shape of cell-cell junctions. In this study, we develop a continuum mechanical model of the cell-cell junction by explicitly incorporating the cell membrane, distributions of E-cadherin bonds, cytoplasmic fluid pressure, and F-actin dynamics. The static force-balanced version of the model is able to analyze the influences of cell cortical tension, actin dynamics, and cytoplasmic pressure on the junction shape and E-cadherin bonds. Furthermore, an extended model that incorporates fluid flow, across the cell boundary as well as around the cell, is also examined. This model can couple cell-shape changes with cell cortical tension and fluid flow, and predicts the additional effect of fluid motion on cell-cell junction mechanics. Taken together, our models serve as an intermediate link between molecular-scale models of cell-junction molecules and cell-scale models of tissue and epithelia.
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Caderinas , Junções Intercelulares , Junções Intercelulares/metabolismo , Caderinas/metabolismo , Actinas/metabolismo , Membrana Celular/metabolismo , Citoesqueleto de Actina/metabolismoRESUMO
The total syntheses of nine grayanane diterpenoids, namely, GTX-II (1), GTX-III (2), rhodojaponin III (3), GTX-XV (4), principinol D (5), iso-GTX-II (6), 1,5-seco-GTX-Δ1,10-ene (7), and leucothols B (8) and D (9), that belong to five distinct subtypes, were disclosed in a divergent manner. Among them, six members were accomplished for the first time. The concise synthetic approach features three key transformations: (1) an oxidative dearomatization-induced [5 + 2] cycloaddition/pinacol rearrangement cascade to assemble the bicyclo[3.2.1]octane carbon framework (CD rings); (2) a photosantonin rearrangement to build up the 5/7 bicycle (AB rings) of 1-epi-grayanoids; and (3) a Grob fragmentation/carbonyl-ene process to access four additional subtypes of grayanane skeletons. Density functional theory calculations were performed to elucidate the mechanistic origins of the crucial divergent transformation, which combined with late-stage synthetic findings provided insights into the biosynthetic relationships between these diverse skeletons.
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Parkinson's disease (PD) is mainly characterized by the progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and neuroinflammation mediated by overactivated microglia and astrocytes. NLRC5 (nucleotide-binding oligomerization domain-like receptor family caspase recruitment domain containing 5) has been reported to participate in various immune disorders, but its role in neurodegenerative diseases remains unclear. In the current study, we found that the expression of NLRC5 was increased in the nigrostriatal axis of mice with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP)-induced PD, as well as in primary astrocytes, microglia and neurons exposed to different neurotoxic stimuli. In an acute MPTP-induced PD model, NLRC5 deficiency significantly reduced dopaminergic system degeneration and ameliorated motor deficits and striatal inflammation. Furthermore, we found that NLRC5 deficiency decreased the expression of the proinflammatory genes IL-1ß, IL-6, TNF-α and COX2 in primary microglia and primary astrocytes treated with neuroinflammatory stimuli and reduced the inflammatory response in mixed glial cells in response to LPS treatment. Moreover, NLRC5 deficiency suppressed activation of the NF-κB and MAPK signaling pathways and enhanced the activation of AKT-GSK-3ß and AMPK signaling in mixed glial cells. Furthermore, NLRC5 deficiency increased the survival of primary neurons treated with MPP+ or conditioned medium from LPS-stimulated mixed glial cells and promoted activation of the NF-κB and AKT signaling pathways. Moreover, the mRNA expression of NLRC5 was decreased in the blood of PD patients compared to healthy subjects. Therefore, we suggest that NLRC5 promotes neuroinflammation and dopaminergic degeneration in PD and may serve as a marker of glial activation.
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Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doenças Neuroinflamatórias , NF-kappa B/metabolismo , Proteínas NLR/metabolismo , Lipopolissacarídeos/metabolismo , Glicogênio Sintase Quinase 3 beta , Proteínas Proto-Oncogênicas c-akt/metabolismo , Microglia/metabolismo , Neurônios Dopaminérgicos/metabolismo , Dopamina/metabolismo , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismoRESUMO
In eukaryotes, the cell volume is observed to be strongly correlated with the nuclear volume. The slope of this correlation depends on the cell type, growth condition, and the physical environment of the cell. We develop a computational model of cell growth and proteome increase, incorporating the kinetics of amino acid import, protein/ribosome synthesis and degradation, and active transport of proteins between the cytoplasm and the nucleoplasm. We also include a simple model of ribosome biogenesis and assembly. Results show that the cell volume is tightly correlated with the nuclear volume, and the cytoplasm-nucleoplasm transport rates strongly influence the cell growth rate as well as the cell/nucleus volume ratio (C/N ratio). Ribosome assembly and the ratio of ribosomal proteins to mature ribosomes also influence the cell volume and the cell growth rate. We find that in order to regulate the cell growth rate and the cell/nucleus volume ratio, the cell must optimally control groups of kinetic and transport parameters together, which could explain the quantitative roles of canonical growth pathways. Finally, although not explicitly demonstrated in this work, we point out that it is possible to construct a detailed proteome distribution using our model and RNAseq data, provided that a quantitative cell division mechanism is known.
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Células Eucarióticas , Proteoma , Transporte Ativo do Núcleo Celular , Núcleo Celular/metabolismo , Células Eucarióticas/metabolismo , Proteoma/metabolismo , RNA Ribossômico , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismoRESUMO
Dysregulated B cell receptor-associated protein 31 (BAP31) plays a crucial role in tumor progression. This study aimed to investigate the functions and molecular mechanism of BAP31 on the miR-206/133b cluster in colorectal cancer (CRC). qPCR was conducted to detect miRNA and mRNA levels in tissues and cells. Western blot assays were used to assess the levels of biomarkers and targets, as well as the levels of BAP31 and HOXD10. Wound healing, coculture and transwell assays were conducted to assess the transendothelial migration abilities of CRC cells. A luciferase assay was employed to assess miRNA binding effects on targets, as well as the initiating transcription effect of genomic fragments. Tumor growth and lung metastatic models were established through an in vivo animal study. BAP31 overexpression in CRC cells led to a reduction in the expression of the miR-206/133b cluster. The expression of the miR-206/133b cluster was correlated with the transendothelial migration capability of CRC cells. The miR-206/133b cluster was found to directly regulate cell division cycle 42 (CDC42) and actin-related protein 2/3 complex subunit 5 (ARPC5) in the tight junction pathway (hsa04530). Moreover, a potential transcription regulator of the miR-206/133b cluster was also found to be Homeobox D10 (HOXD10). We further elucidated the molecular mechanisms and functional mechanisms of BAP31's regulatory role in the expression levels of the miR-206/133b cluster by inhibiting HOXD10 translocation from the cytoplasm to the nucleus. In conclusion, this study provides valuable insights into how BAP31 regulates the transcription of the miR-206/133b cluster and how BAP31-related lung metastases arise in CRC.
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Neoplasias Colorretais , Neoplasias Pulmonares , MicroRNAs , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Migração Transendotelial e TransepitelialRESUMO
Liriogerphines A-D (1-4, respectively), an unprecedented class of hybrids of germacranolide-type sesquiterpenoids and aporphine-type alkaloids, were isolated from the rare medicinal plant Liriodendron chinense. Their structures were elucidated by comprehensive spectroscopic analyses combined with electronic circular dichroism calculations and X-ray crystallographic data. Biosynthetically, an aza-Michael addition reaction is proposed to be involved in the assemblies of this class of hybrids. Compound 4 exhibited cytotoxicity against leukemia cells via inducing apoptosis and inhibiting Bcl-2 expression.
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Alcaloides , Antineoplásicos , Liriodendron , Sesquiterpenos , Alcaloides/química , Alcaloides/farmacologia , China , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos/farmacologia , ÁrvoresRESUMO
Plasmid high-density lipoprotein (HDL) is a critical biomarker in predicting cardiovascular diseases. Endothelial cells are physically located in the intima of blood vessels, which directly contact with circulating substances. Numerous previous studies have demonstrated that HDL exert protective effects on maintaining endothelial integrity and enhance anti-inflammatory functions, etc. In this chapter, we introduced how HDL benefit endothelial functions. We summarized the function of HDL on endothelial cell, such as endothelial permeability, proliferation, migration, apoptosis, etc. In addition, we discussed the effects of HDL on classical endothelial functions, such as coagulation and vasodilation. Although HDL have huge effects on endothelial functions, lots of cardiovascular diseases such as atherosclerosis could not be fully prevented and treated. Thus, a further understanding of the relationship between HDL and endothelial cell is needed, which would create a potential therapeutic approach to cardiovascular diseases.
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Aterosclerose , Doenças Cardiovasculares , Aterosclerose/genética , Células Endoteliais , Humanos , Lipoproteínas HDL , VasodilataçãoRESUMO
OBJECTIVE: Whether periodontitis increases the risk of diabetic microangiopathy remains controversial. The present meta-analysis aims to investigate the relationship between periodontitis and diabetic microangiopathy in patients with type 2 diabetes mellitus. METHODS: PubMed, EMBASE, Web of Science, the Cochrane Library, CNKI, and WanFang data were searched without language restrictions. The methodological quality of the studies included was assessed using Newcastle-Ottawa Scale method, and meta-analysis was performed by Review Manager 5.3. Odds ratio (OR) and 95% confidence interval (CI) were used to assess the risk of periodontitis for diabetic microangiopathy among patients with type 2 diabetes. RESULTS: Thirteen cross-sectional studies, covering 10 570 participants, were included in the present meta-analysis. The results demonstrated that periodontitis was associated with increased risk of type 2 diabetic microangiopathy (OR: 2.43, 95% CI: 1.65-3.56), diabetic retinopathy (OR: 4.33, 95% CI: 2.19-8.55), and diabetic nephropathy (OR: 1.75, 95% CI: 1.07-2.85), while periodontitis was not associated with diabetic neuropathy (OR: 0.99, 95% CI: 0.19-5.12). Subgroup analysis among the studies in Asian (OR: 3.06, 95% CI: 1.94-4.84) and North American (OR: 1.42, 95% CI: 1.08-1.86) populations confirmed the existed association between periodontitis and type 2 diabetic microangiopathy. The relationship still existed in groups with sample size larger than 500 (OR: 1.77, 95% CI: 1.34-2.34) and smaller than 500 (OR: 3.33, 95% CI: 1.38-8.03). A sensitivity analysis confirmed the stability of the results by excluding moderate quality studies or removing articles one after the other. CONCLUSION: Current evidences have proved that periodontitis is associated with increased risk of diabetic microangiopathy in patients with type 2 diabetes mellitus. This conclusion may provide useful evidence for correlated clinical researches. PROSPERO registration number CRD42021247773.
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Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Retinopatia Diabética , Periodontite , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Periodontite/complicações , Periodontite/epidemiologiaRESUMO
An asymmetric approach for the first total synthesis of (-)-rhodomollanol A, a highly oxidized diterpenoid, is described. The efficient synthetic strategy features three key transformations: (1) an oxidative dearomatization-induced (5 + 2) cycloaddition/pinacol-type 1,2-acyl migration cascade to build up the bicyclo[3.2.1]octane skeleton; (2) a retro-Dieckmann fragmentation/vinylogous Dieckmann cyclization cascade to assemble the bicyclo[3.3.0]octane subunit; and (3) a photo-Nazarov cyclization/intramolecular cycloetherification cascade to forge the 7-oxabicyclo[4.2.1]nonane core structure of the natural product.
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Diterpenos/síntese química , Reação de Cicloadição , Oxirredução , EstereoisomerismoRESUMO
Active spectral tuning of nanophotonic devices offers many fascinating prospects for the realization of novel optical function. Here, switchable spectral response is enabled by the architecture of one-dimensional (1D) photonic crystal (PC) integrated with phase change material of the germanium antimony telluride (GST). Active and precise tuning of the bistable passband and central resonant frequency is demonstrated in the 1D PC composed of alternate SiN and GST nanofilms. An analytical model is derived to specify the tunable spectral features, including the band gap and resonant frequencies. Both the measured and calculated results show distinct red shifts of passband and the resonant minima (or maxima), well confirming theoretical predictions. This work demonstrates a route to construct active photonic devices with the electrically or thermally tunable spectra via 1D PC and potentially extends diverse applications based on the PC platform.
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PURPOSE: To determine the changes of the microvasculature and microstructure in the inner intra-retinal layers in systemic lupus erythematosus (SLE) patients without lupus retinopathy (LR). METHODS: Thirty-two SLE patients (58 eyes) without LR (NLR), 14 patients (22 eyes) with LR and 50 healthy subjects (50 eyes) were enrolled. Spectral domain optical coherence tomography equipped with Angiovue was used to obtain three-dimensional retinal thickness maps and microvascular images of the superficial and deep retinal capillary plexuses (SRCP/DRCP) around the macula. Quantitative analyses were performed using a custom automated algorithm. Disease activity of patients was assessed using the SLE disease activity index (SLEDAI). RESULTS: Retinal capillary skeleton density of the SRCP in SLE patients without LR was significantly lower than the controls in almost all regions, which further decreased in the LR group (Pâ¯<â¯.05). No significant changes were evident in DRCP of the NLR group (Pâ¯>â¯.05). The inner retina in the LR group was significantly thinner than the controls in most regions, though there were only a few regions that were different between the NLR and the control groups (Pâ¯<â¯.05). There were significant differences of the SLEDAI scores between the two SLE groups. CONCLUSION: Significantly lower density in SRCP and regional thinning in inner retina were observed in the SLE patients without clinical fundus changes. OCT equipped with Angiovue might be useful in evaluating the microvascular and microstructural disorders of the inner retinal layers in SLE patients, which may contribute a quantitative approach to the early diagnosis and progression of LR.
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Lúpus Eritematoso Sistêmico/complicações , Microvasos/diagnóstico por imagem , Doenças Retinianas/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica , Adulto , Doenças Assintomáticas , Estudos de Casos e Controles , Diagnóstico Precoce , Feminino , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Doenças Retinianas/etiologia , Adulto JovemRESUMO
Background: The serum lipid profile has become a routine clinical test and used as an important predictor for Alzheimer's disease (AD), although its predictive value remains undetermined. Objective: To evaluate the role of serum lipid levels in predicting the risk of AD. Methods: Meta-analyses were conducted using Comprehensive Meta-analyses (CMA) software to investigate the association between four conventional serum lipid profile parameters and the risk of AD, focused on samples from Asian. Results: In total, 3423 AD patients and 6127 healthy participants were involved. The results demonstrated that AD patients showed higher LDL-C and TC levels (SMD = 0.27, 95% CI: 0.04-0.51, p = 0.02 for LDL-C; SMD = 0.25, 95% CI: 0.05-0.46, p = 0.02 for TC) compared with those of healthy controls. People with higher LDL-C and/or TC levels had an increased risk of AD (OR = 1.64, 95% CI: 1.07-2.51 for LDL-C and OR = 1.58, 95% CI: 1.10-2.92 for TC). Conclusions: This study provided evidence that serum LDL-C and TC levels were associated with the risk of AD in Asian individuals. The routine lipid profile may be useful for AD diagnosis, monitoring and treatment.
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Doença de Alzheimer/diagnóstico , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Triglicerídeos/sangue , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/sangue , Doença de Alzheimer/etnologia , Povo Asiático , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de RiscoRESUMO
Low-density lipoprotein receptor-related protein 6 (LRP6) serves as a Wnt coreceptor. Although Wnt/LRP6 signalling is best known for the ß-catenin-dependent regulation of target genes in tissue development and homeostasis, emerging evidence demonstrates the biological aspects of LRP6 beyond a Wnt coreceptor. Whether LRP6 modulates tissue development in a Wnt/ß-catenin signalling-independent manner remains unknown. Using a model of striated muscle development, we observed that LRP6 was almost undetectable in proliferating myoblasts, whereas its expression gradually increased in the nucleus of myodifferentiating cells. During myodifferentiation, LRP6 modulated the muscle-specific splicing of integrin-ß1D and consequent myotube maturation independently of the ß-catenin-dependent Wnt signalling. Furthermore, we identified that the carboxy-terminal serine-rich region in LRP6 bond to the adenine-rich sequence within alternative exon D (AED) of integrin-ß1 pre-mRNA, and therefore, elicited AED inclusion when the spliceosome was recruited to the splice site. The interaction of LRP6 with the adenine-rich sequence was sufficient to overcome AED exclusion by a splicing repressor, polypyrimidine tract binding protein-1. Besides the integrin-ß1, deep RNA sequencing in different types of cells revealed that the LRP6-mediated splicing regulation was widespread. Thus, our findings implicate LRP6 as a potential regulator for alternative pre-mRNA splicing.
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Processamento Alternativo , Regulação da Expressão Gênica no Desenvolvimento , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Desenvolvimento Muscular/genética , Músculo Estriado/metabolismo , Precursores de RNA/genética , Animais , Animais Recém-Nascidos , Sequência de Bases , Diferenciação Celular , Linhagem Celular , Núcleo Celular/metabolismo , Proliferação de Células , Citosol/metabolismo , Éxons , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Integrina beta1/genética , Integrina beta1/metabolismo , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Camundongos , Músculo Estriado/citologia , Músculo Estriado/crescimento & desenvolvimento , Mioblastos/citologia , Mioblastos/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Cultura Primária de Células , Precursores de RNA/metabolismo , Ratos , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismoRESUMO
RATIONALE: Cold-inducible RNA-binding protein (CIRP) is constitutively expressed at low levels across various tissues. It is rapidly upregulated by multiple stresses, underlying a general role for CIRP in organic adaptations to pathophysiological conditions. However, the role of CIRP in the heart remains unclear. OBJECTIVE: To examine the biofunctions of CIRP in the mammalian heart. METHODS AND RESULTS: Rats with targeted disruption of Cirp were generated using the TALEN (transcription activator-like effector nucleases)-based genome editing technique. The Cirp-knockout rats had structurally and functionally normal hearts. Resting ECG recordings revealed a short rate-corrected QT (QTc) interval in Cirp-null rats without any abnormalities in PR interval, RR interval or QRS waves as compared to wild-type animals. The shortened QTc interval from Cirp ablation was tightly linked to an abbreviated action potential duration in cardiac myocytes, which was attributable to increased transient outward potassium current (Ito). Furthermore, our findings uncovered that CIRP protein selectively bonded to KCND2 and KCND3 mRNAs encoding the functional α-subunits of Ito channel proteins. CIRP deficiency did not change the transcriptional activity of KCND2 or KCND3, but it facilitated their translation. Cirp knockout had no effect on the functional expression of ion channels other than Ito channels. CONCLUSIONS: CIRP modulates cardiac repolarization by negatively adjusting the expression and function of Ito channels. Our study may open a window to decipher the potential function of RNA-binding proteins in bioelectric activity.
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Proteínas e Peptídeos de Choque Frio/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Canais de Potássio Shal/metabolismo , Potenciais de Ação , Animais , Sítios de Ligação , Células Cultivadas , Proteínas e Peptídeos de Choque Frio/deficiência , Proteínas e Peptídeos de Choque Frio/genética , Genótipo , Frequência Cardíaca , Ativação do Canal Iônico , Proteínas Interatuantes com Canais de Kv/genética , Proteínas Interatuantes com Canais de Kv/metabolismo , Fenótipo , Ligação Proteica , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Ratos Transgênicos , Canais de Potássio Shal/genética , Fatores de Tempo , Transcrição Gênica , TransfecçãoRESUMO
A modified Bouveault-Blanc reduction has been developed for the synthesis of α,α-dideuterio alcohols from carboxylic acid esters. Sodium dispersions are used as the electron donor in this electron transfer reaction, and ethanol-d1 is employed as the deuterium source. This reaction uses stable, cheap, and commercially available reagents, is operationally simple, and results in excellent deuterium incorporation across a broad range of aliphatic esters, which provides an attractive alternative to reactions mediated by expensive pyrophoric alkali metal deuterides.