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Understanding the regulatory mechanisms facilitating hematopoietic stem cell (HSC) specification during embryogenesis is important for the generation of HSCs in vitro. Megakaryocyte emerged from the yolk sac and produce platelets, which are involved in multiple biological processes, such as preventing hemorrhage. However, whether megakaryocytes regulate HSC development in the embryonic aorta-gonad-mesonephros (AGM) region is unclear. Here, we use platelet factor 4 (PF4)-Cre;Rosa-tdTomato+ cells to report presence of megakaryocytes in the HSC developmental niche. Further, we use the PF4-Cre;Rosa-DTA (DTA) depletion model to reveal that megakaryocytes control HSC specification in the mouse embryos. Megakaryocyte deficiency blocks the generation and maturation of pre-HSCs and alters HSC activity at the AGM. Furthermore, megakaryocytes promote endothelial-to-hematopoietic transition in a OP9-DL1 coculture system. Single-cell RNA-sequencing identifies megakaryocytes positive for the cell surface marker CD226 as the subpopulation with highest potential in promoting the hemogenic fate of endothelial cells by secreting TNFSF14. In line, TNFSF14 treatment rescues hematopoietic cell function in megakaryocyte-depleted cocultures. Taken together, megakaryocytes promote production and maturation of pre-HSCs, acting as a critical microenvironmental control factor during embryonic hematopoiesis.
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Células Madre Hematopoyéticas , Megacariocitos , Animales , Megacariocitos/citología , Megacariocitos/metabolismo , Ratones , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Diferenciación Celular , Hematopoyesis/fisiología , Mesonefro/embriología , Mesonefro/metabolismo , Mesonefro/citología , Células Endoteliales/metabolismo , Células Endoteliales/citología , Técnicas de CocultivoRESUMEN
Genetic deficiency of alpha-L-iduronidase causes mucopolysaccharidosis type I (MPS-I) disease, due to accumulation of glycosaminoglycans (GAGs) including chondroitin/dermatan sulfate (CS/DS) and heparan sulfate (HS) in cells. Currently, patients are treated by infusion of recombinant iduronidase or by hematopoietic stem cell transplantation. An alternative approach is to reduce the L-iduronidase substrate, through limiting the biosynthesis of iduronic acid. Our earlier study demonstrated that ebselen attenuated GAGs accumulation in MPS-I cells, through inhibiting iduronic acid producing enzymes. However, ebselen has multiple pharmacological effects, which prevents its application for MPS-I. Thus, we continued the study by looking for novel inhibitors of dermatan sulfate epimerase 1 (DS-epi1), the main responsible enzyme for production of iduronic acid in CS/DS chains. Based on virtual screening of chemicals towards chondroitinase AC, we constructed a library with 1,064 compounds that were tested for DS-epi1 inhibition. Seventeen compounds were identified to be able to inhibit 27%-86% of DS-epi1 activity at 10 µM. Two compounds were selected for further investigation based on the structure properties. The results show that both inhibitors had a comparable level in inhibition of DS-epi1while they had negligible effect on HS epimerase. The two inhibitors were able to reduce iduronic acid biosynthesis in CS/DS and GAG accumulation in WT and MPS-I fibroblasts. Docking of the inhibitors into DS-epi1 structure shows high affinity binding of both compounds to the active site. The collected data indicate that these hit compounds may be further elaborated to a potential lead drug used for attenuation of GAGs accumulation in MPS-I patients.
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Inhibidores Enzimáticos , Fibroblastos , Glicosaminoglicanos , Mucopolisacaridosis I , Mucopolisacaridosis I/tratamiento farmacológico , Mucopolisacaridosis I/metabolismo , Mucopolisacaridosis I/patología , Humanos , Fibroblastos/metabolismo , Fibroblastos/efectos de los fármacos , Glicosaminoglicanos/metabolismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Carbohidrato Epimerasas/metabolismo , Carbohidrato Epimerasas/antagonistas & inhibidores , Carbohidrato Epimerasas/genética , Simulación del Acoplamiento Molecular , Antígenos de Neoplasias , Proteínas de Unión al ADN , Proteínas de NeoplasiasRESUMEN
Background: Labeled antibodies are excellent imaging agents in oncology to non-invasively visualize cancer-related antigens expression levels. However, tumor tracer uptake (TTU) of specific antibodies in-vivo may be inferior to non-specific IgG in some cases. Objectives: To explore factors affecting labeled antibody visualization by PD-L1 specific and non-specific imaging of nude mouse tumors. Methods: TTU was observed in RKO model on Cerenkov luminescence (CL) and near-infrared fluorescence (NIRF) imaging of radionuclide 131I or NIRF dyes labeled Atezolizumab and IgG. A mixture of NIRF dyes labeled Atezolizumab and 131I-labeled IgG was injected, and TTU was observed in the RKO and HCT8 model by NIRF/CL dual-modality in-situ imaging. TTU were observed by 131I-labeled Atezolizumab and IgG in-vitro distribution. Results: Labeled IgG concentrated more in tumors than Atezolizumab. NIRF/CL imaging in 24 to 168 h showed that TTU gradually decreased over time, which decreased more slowly on CL imaging compared to NIRF imaging. The distribution data in-vitro showed that TTU of 131I-labeled IgG was higher than that of 131I-labeled Atezolizumab at any time point. Conclusion: Non-specific IgG may not be suitable as a control for Atezolizumab in comparing tumor PD-L1 expression in nude mice via labeled antibody optical imaging under certain circumstances.
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Antígeno B7-H1 , Ratones Desnudos , Animales , Antígeno B7-H1/metabolismo , Humanos , Ratones , Línea Celular Tumoral , Anticuerpos Monoclonales Humanizados/química , Anticuerpos Monoclonales Humanizados/farmacocinética , Imagen Óptica/métodos , Radioisótopos de Yodo/química , Neoplasias/diagnóstico por imagen , Inmunoglobulina G/química , Inmunoglobulina G/metabolismo , Femenino , LuminiscenciaRESUMEN
BACKGROUND AND PURPOSE: The association between overweight/obesity and postmenopausal breast cancer has been proven. However, uncertainty exists regarding the association between physical weight statuses and premenopausal breast cancer subtypes. This study aimed to explore the association of body weight statuses with molecular subtypes of premenopausal breast cancer. METHOD: A systematic search of Medline, PubMed, Embase, and Web of Science was performed. The Newcastle-Ottawa Scale (NOS) and the Joanna Briggs Institute (JBI) Critical Appraisal tools were used to evaluate the quality of the literature. STATA and R software were used to analyze the extracted data. RESULT: The meta-analysis included 35 observational studies with a total of 41,049 premenopausal breast cancer patients. The study showed that the proportion of underweight patients was 4.8% (95% CI = 3.9-5.8%, P = 0.01), overweight was 29% (95%CI = 27.1-30.9%, P < 0.01), obesity was 17.8% (95% CI = 14.9-21.2%, P < 0.0001), and normal weight was 51.6% (95% CI = 46.7-56.5%, P < 0.0001). The pooled results showed that in comparison to the normal weight group, being physically underweight is related to a 1.44-fold risk (OR = 1.44, 95%CI = 1.28-1.63, P < 0.0001) of HER2 + breast cancer. Overweight is related to a 1.16-fold risk (OR = 1.16, 95%CI = 1.06-1.26, P = 0.002) of TNBC and a 16% lower risk (OR = 0.84, 95%CI = 0.75-0.93, P = 0.001) of ER + breast cancer. When compared to underweight/normal weight populations, both overweight (OR = 0.74, 95%CI = 0.56-0.97, P = 0.032) and obesity (OR = 0.70, 95%CI = 0.50-0.98, P = 0.037) can reduce the risk of ER + PR + breast cancer. CONCLUSION: In the premenopausal breast cancer population, the distribution of patients' numbers with different weight statuses was significantly distinct among the various breast cancer subtypes. Additionally, the associations between physical weight statuses and the risk of premenopausal breast cancer subtypes are divergent.
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Neoplasias de la Mama , Sobrepeso , Femenino , Humanos , Índice de Masa Corporal , Neoplasias de la Mama/etiología , Neoplasias de la Mama/complicaciones , Obesidad/complicaciones , Obesidad/epidemiología , Sobrepeso/complicaciones , Sobrepeso/epidemiología , Premenopausia , Receptores de Estrógenos/análisis , Factores de Riesgo , Delgadez/epidemiología , Delgadez/complicacionesRESUMEN
The design of electrocatalysts for oxygen evolution reaction (OER) remains a limitation of industrial hydrogen production by electrolysis of water. Excellent and stable OER catalysts can be developed by activating lattice oxygen and changing the reaction path. Herein, S and FeOOH on the Co(OH)2 nanoneedle arrays are introduced to construct a heterostructure (S-FeOOH/Co(OH)2/NF) as a proof of concept. Theoretical calculations and experimental suggest that the Co-O-Fe motif formed at the heterogeneous interface with the introduction of FeOOH, inducing electron transfer from Co to Fe, enhancing CoâO covalency and reducing intramolecular charge transfer energy, thereby stimulating direct intramolecular lattice oxygen coupling. Doping of S in FeOOH further accelerates electron transfer, improves lattice oxygen activity, and prevents dissolution of FeOOH. Consequently, the overpotential of S-FeOOH/Co(OH)2/NF is only 199 mV at 10 mA cm-2, and coupled with the Pt/C electrode can be up to 1 A cm-2 under 1.79 V and remain stable for over 120 h in an anion exchange membrane water electrolyzer (AEMWE). This work proposes a strategy for the design of efficient and stable electrocatalysts for industrial water electrolysis and promotes the commercialization of AEMWE.
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BACKGROUND: Alzheimer's disease (AD), affecting many elders worldwide, is characterized by A-beta and tau-related cognitive decline. Accumulating evidence suggests that brain iron accumulation is an important characteristic of AD. However, the function and mechanism of the iron-mediated gut-brain axis on AD is still unclear. METHODS: A Caenorhabditis elegans model with tau-overexpression and a high-Fe diet mouse model of cognitive impairment was used for probiotic function evaluation. With the use of qPCR, and immunoblotting, the probiotic regulated differential expression of AD markers and iron related transporting genes was determined. Colorimetric kits, IHC staining, and immunofluorescence have been performed to explore the probiotic mechanism on the development of gut-brain links and brain iron accumulation. RESULTS: In the present study, a high-Fe diet mouse model was used for evaluation in which cognitive impairment, higher A-beta, tau and phosphorylated (p)-tau expression, and dysfunctional phosphate distribution were observed. Considering the close crosstalk between intestine and brain, probiotics were then employed to delay the process of cognitive impairment in the HFe mouse model. Pediococcus acidilactici (PA), but not Bacillus subtilis (BN) administration in HFe-fed mice reduced brain iron accumulation, enhanced global alkaline phosphatase (AP) activity, accelerated dephosphorylation, lowered phosphate levels and increased brain urate production. In addition, because PA regulated cognitive behavior in HFe fed mice, we used the transgenic Caenorhabditis elegans with over-expressed human p-tau for model, and then PA fed worms became more active and longer lived than E.coli fed worms, as well as p-tau was down-regulated. These results suggest that brain iron accumulation influences AD risk proteins and various metabolites. Furthermore, PA was shown to reverse tau-induced pathogenesis via iron transporters and AP-urate interaction. CONCLUSIONS: PA administration studies demonstrate that PA is an important mediator of tau protein reduction, p-tau expression and neurodegenerative behavior both in Caenorhabditis elegans and iron-overload mice. Finally, our results provide candidates for AP modulation strategies as preventive tools for promoting brain health. Video Abstract.
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Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Pediococcus acidilactici , Ratones , Animales , Humanos , Anciano , Pediococcus acidilactici/metabolismo , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/metabolismo , Caenorhabditis elegans/metabolismo , Ácido Úrico , Ratones Transgénicos , Enfermedad de Alzheimer/metabolismo , Hierro , FosfatosRESUMEN
Biomacromolecular condensates formed via phase separation establish compartments for the enrichment of specific compositions, which is also used as a biological tool to enhance molecule condensation, thereby increasing the efficiency of biological processes. Proteolysis-targeting chimeras (PROTACs) have been developed as powerful tools for targeted protein degradation in cells, offering a promising approach for therapies for different diseases. Herein, we introduce an intrinsically disordered region in the PROTAC (denoted PSETAC), which led to the formation of droplets of target proteins in the cells and increased degradation efficiency compared with PROTAC without phase separation. Further, using a nucleus targeting intrinsically disordered domain, the PSETAC was able to target and degrade nuclear-located proteins. Finally, we demonstrated intracellular delivery of PSETAC using lipid nanoparticle-encapsulated mRNA (mRNA-LNP) for the degradation of the endogenous target protein. This study established the PSETAC mRNA-LNP method as a potentially translatable, safe therapeutic strategy for the development of clinical applications based on PROTAC.
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Proteolisis , ARN Mensajero , Proteolisis/efectos de los fármacos , Humanos , ARN Mensajero/genética , Nanopartículas/química , Lípidos/química , Células HeLa , Proteínas Intrínsecamente Desordenadas/química , Proteínas Intrínsecamente Desordenadas/metabolismo , Separación de Fases , LiposomasRESUMEN
AAK1, also known as AP2-associated protein kinase 1, is an enzyme that belongs to the family of serine/threonine protein kinases. It regulates the assembly and disassembly of clathrin-coated pits and thereby protein endocytosis, by phosphorylating the µ2 subunit of the AP2 complex, which is a key component of clathrin-coated vesicles. LX9211 is currently the only selective small molecule AAK1 inhibitor at the clinical trial stage for diabetic peripheral neuropathic pain, which was found to be safe and well tolerated in healthy participants in phase I clinical trials. The present manuscript described a series of fused-ring derivatives as a novel class of potent AAK1 inhibitors, resulting in the discovery of compound 5, namely HW161023, which showed high inhibitory potency against AAK1 enzyme and satisfactory oral pharmacokinetic profile with weaker HepG2 cell toxicity and hERG inhibition than LX9211.
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Nitrous oxide (N2O), as the third largest greenhouse gas in the world, also has great applications in industry, so the purification of N2O from N2 in industrial tail gas is a crucial process for achieving environmental protection and giving full play to its economic value. Based on the polarity difference of N2O and N2, N2O adsorption was researched on DMOF series materials with different polarities and methyl numbers of the ligand. N2O adsorption at 0.1 bar is enhanced, attributed to an increase of the methyl group densities at the benzenedicarboxylate linker. Grand canonical Monte Carlo simulations demonstrate the key role of methyl groups within the pore surface in the preferential N2O affinity. Methyl groups preferentially bind to N2O and thus enhanced low (partial) pressure N2O adsorption and N2O/N2 separation. The result shows that DMOF-TM has the highest N2O adsorption capacity (19.6 cm3/g) and N2O/N2 selectivity (23.2) at 0.1 bar. Breakthrough experiments show that, with an increase of the methyl number, the coadsorption time and retention time also increase, and DMOF-TM has the best N2O/N2 separation performance.
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Chromium-based metal-organic frameworks (Cr-MOFs) are very attractive in a wide range of applications due to their robustness and high porosity. However, the kinetic inertness of chromium ions results in the synthesis of Cr-MOFs often taking prolonged reaction times, which limit their industrial applications. Herein, we report a novel synthesis strategy based on coordination substitution, which overcomes the kinetic inertness of chromium ions and can synthesize Cr-MOFs in a shorter time. The versatility of this strategy has been demonstrated by producing several known Cr-MOFs, such as TYUT-96Cr, MIL-100Cr, MIL-101Cr, and MIL-53Cr. PXRD, SEM, TEM, 77 K N2 adsorption, and TGA have proved that the Cr-MOFs synthesized using this new strategy have good crystallinity, high porosity, and excellent thermal stability. The synthesis mechanism was investigated using theoretical calculations.
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BACKGROUND: Dialytic phosphate removal is a cornerstone of the management of hyperphosphatemia in peritoneal dialysis (PD) patients, but the influencing factors on peritoneal phosphate clearance (PPC) are incompletely understood. Our objective was to explore clinically relevant factors associated with PPC in patients with different PD modality and peritoneal transport status and the association of PPC with mortality. METHODS: This is a cross-sectional and prospective observational study. Four hundred eighty-five PD patients were enrolled and divided into 2 groups according to PPC. All-cause mortality was evaluated after followed-up for at least 3 months. RESULTS: High PPC group showed lower mortality compared with Low PPC group by Kaplan-Meier analysis and log-rank test. Both multivariate linear regression and multivariate logistic regression revealed that high transport status, total effluent dialysate volume per day, continuous ambulatory PD (CAPD), and protein in total effluent dialysate volume appeared to be positively correlated with PPC; body mass index (BMI) and the normalized protein equivalent of total nitrogen appearance (nPNA) were negatively correlated with PPC. Besides PD modality and membrane transport status, total effluent dialysate volume showed a strong relationship with PPC, but the correlation differed among PD modalities. CONCLUSIONS: Higher PPC was associated with lower all-cause mortality risk in PD patients. Higher PPC correlated with CAPD modality, fast transport status, higher effluent dialysate volume and protein content, and with lower BMI and nPNA.
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Hiperfosfatemia , Fallo Renal Crónico , Diálisis Peritoneal , Fosfatos , Humanos , Masculino , Femenino , Persona de Mediana Edad , Estudios Prospectivos , Diálisis Peritoneal/mortalidad , Estudios Transversales , Fosfatos/metabolismo , Fosfatos/análisis , Hiperfosfatemia/etiología , Fallo Renal Crónico/terapia , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/metabolismo , Anciano , Diálisis Peritoneal Ambulatoria Continua/mortalidad , Soluciones para Diálisis , AdultoRESUMEN
Microaerobic sludge bed systems could align with low-energy, reasonable carbon-nitrogen (C/N) ratio, and synchronous removal objectives during wastewater treatment. However, its ability to treat municipal wastewater (MW) with varying low C/N ratio, low NH4+ concentration, along with managing sludge bulking and loss are still unclear. Against this backdrop, this study investigated the performance of an Upflow Microaerobic Sludge Bed Reactor (UMSR) treating MW characterized by varying low C/N ratios and low NH4+ concentrations. The study also thoroughly examined associated sludge bulking and loss, pollutant removal efficiencies, sludge settleability, microbial community structures, functional gene variations, and metabolic pathways. Findings revealed that the effluent NH4+-N concentration gradually decreased to 0 mg/L with a decrease in the C/N ratio, whereas the effluent COD was unaffected by the influent, maintaining a concentration below 50 mg/L. Notably, TN removal efficiency reached 90% when C/N ratio was 3. The decrease in the C/N ratio (C/N ratio was 1) increased microbial community diversity, with abundances of AOB, AnAOB, aerobic denitrifying bacteria, and anaerobic digestion bacteria reaching 8.34%, 0.96%, 5.07%, and 9.01%, respectively. Microorganisms' metabolic pathways significantly shifted, showing increased carbohydrate and cofactor/vitamin metabolism and decreased amino acid metabolism and xenobiotic biodegradation. This study not only provides a solution for the effluent of different pre-capture carbon processes but also demonstrates the UMSR's capability in managing low C/N ratio municipal wastewater and emphasizes the critical role of microbial community adjustments and functional gene variations in enhancing nitrogen removal efficiency.
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Reactores Biológicos , Carbono , Nitrógeno , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Aguas Residuales , Nitrógeno/metabolismo , Nitrógeno/análisis , Carbono/análisis , Carbono/metabolismo , Eliminación de Residuos Líquidos/métodos , Aguas del Alcantarillado/microbiología , Aguas del Alcantarillado/química , Reactores Biológicos/microbiología , Aguas Residuales/microbiología , Aguas Residuales/química , Microbiota , Bacterias/metabolismo , Bacterias/genética , Bacterias/clasificación , AerobiosisRESUMEN
PURPOSE: Over the past several decades, numerous articles have been published on brainstem tumors. However, there has been limited bibliometric analysis in this field. Therefore, we conducted a bibliometric analysis to elucidate the evolution and current status of brainstem tumor research. METHODS: We retrieved 5525 studies published in English between 1992 and 2023 from the Web of Science Core Collection database. We employed bibliometric tools and VOSviewer to conduct the analysis. RESULTS: We included a total of 5525 publications for further analysis. The annual publications have exhibited steady growth over time. The United States accounted for the highest number of publications and total citations. Among individual researchers, Liwei Zhang had the highest number of publications, while Cynthia Hawkins and Chris Jones shared the most citations, closely followed by Eric Bouffet in this field. The study titled "Diffuse brainstem glioma in children: critical review of clinical trials" stood out as the most cited work in this field. Keyword analysis revealed that immune therapy and epigenetic research are the focal points of this field. CONCLUSIONS: Our bibliometric analysis underscores the enduring significance of brainstem tumors in the realm of neuro-oncology research. The field's hotspots have transitioned from surgery and radiochemotherapy to investigating epigenetic mechanisms and immune therapy.
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Bibliometría , Neoplasias del Tronco Encefálico , Humanos , Neoplasias del Tronco Encefálico/terapia , Investigación Biomédica/tendencias , Investigación Biomédica/estadística & datos numéricosRESUMEN
BACKGROUND: Extramural venous invasion (EMVI) is an important prognostic factor of rectal adenocarcinoma. However, accurate preoperative assessment of EMVI remains difficult. PURPOSE: To assess EMVI preoperatively through radiomics technology, and use different algorithms combined with clinical factors to establish a variety of models in order to make the most accurate judgments before surgery. MATERIAL AND METHODS: A total of 212 patients with rectal adenocarcinoma between September 2012 and July 2019 were included and distributed to training and validation datasets. Radiomics features were extracted from pretreatment T2-weighted images. Different prediction models (clinical model, logistic regression [LR], random forest [RF], support vector machine [SVM], clinical-LR model, clinical-RF model, and clinical-SVM model) were constructed on the basis of radiomics features and clinical factors, respectively. The area under the curve (AUC) and accuracy were used to assess the predictive efficacy of different models. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were also calculated. RESULTS: The clinical-LR model exhibited the best diagnostic efficiency with an AUC of 0.962 (95% confidence interval [CI] = 0.936-0.988) and 0.865 (95% CI = 0.770-0.959), accuracy of 0.899 and 0.828, sensitivity of 0.867 and 0.818, specificity of 0.913 and 0.833, PPV of 0.813 and 0.720, and NPV of 0.940 and 0.897 for the training and validation datasets, respectively. CONCLUSION: The radiomics-based prediction model is a valuable tool in EMVI detection and can assist decision-making in clinical practice.
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Adenocarcinoma , Neoplasias del Recto , Humanos , Radiómica , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/cirugía , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/cirugíaRESUMEN
Cigarette smoking is one of the most impactful behavior-related risk factors for multiple cancers including hepatocellular carcinoma (HCC). Nicotine, as the principal component of tobacco, is not only responsible for smoking addiction but also a carcinogen; nevertheless, the underlying mechanisms remain unclear. Here we report that nicotine enhances HCC cancer stemness and malignant progression by upregulating the expression of GC-rich binding factor 2 (GCF2), a gene that was revealed to be upregulated in HCC and whose upregulation predicts poor prognosis, and subsequently activating the Wnt/êµ-catenin/SOX2 signaling pathway. We found that nicotine significantly increased GCF2 expression and that silencing of GCF2 reduced nicotine-induced cancer stemness and progression. Mechanistically, nicotine could stabilize the protein level of GCF2, and then GCF2 could robustly activate its downstream Wnt/ß-catenin signaling pathway. Taken together, our results thus suggest that GCF2 is a potential target for a therapeutic strategy against nicotine-promoted HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/inducido químicamente , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Nicotina/toxicidad , Línea Celular Tumoral , Vía de Señalización Wnt/genética , Regulación Neoplásica de la Expresión Génica , Proliferación CelularRESUMEN
BACKGROUND: Rating scales and linear indices of surface electromyography (sEMG) cannot quantify all neuromuscular conditions associated with ankle-foot dysfunction in hemiplegic patients. This study aimed to reveal potential neuromuscular conditions of ankle-foot dysfunction in hemiplegic patients by nonlinear network indices of sEMG. METHODS: Fourteen male patients with hemiplegia and 10 age- and sex-matched healthy male adults were recruited and tested in static standing position. The characteristics of the root mean square (RMS), median frequency (MF), and three nonlinear indices, the clustering coefficient (C), the average shortest path length (L), and the degree centrality (DC), of eight groups of muscles in bilateral calves were observed. RESULTS: Compared to those of the control group, the RMS of the medial gastrocnemius (MG), flexor digitorum longus (FDL), and extensor digitorum longus (EDL) on the affected side were significantly lower (P < 0.05), and the RMS of the tibial anterior (TA) and EDL on the unaffected side were significantly higher (P < 0.05). The MF of the EDL on the affected side was significantly higher than that on the control side (P < 0.05). The C of the unaffected side was significantly higher than that of the control group, whereas the L was lower (P < 0.05). Compared to those of the control group, the DC of the TA, EDL, and soleus (SOL) on the unaffected sides were higher (P < 0.05), and the DC of the MG on the affected sides was lower (P < 0.05). CONCLUSION: The change trends and clinical significance of these three network indices, including C, L, and DC, are not in line with those of the traditional linear indices, the RMS and the MF. The C and L may reflect the degree of synchronous activation of muscles during a certain motor task. The DC might be able to quantitatively assess the degree of muscle involvement and reflect the degree of involvement of a single muscle. Linear and nonlinear indices may reveal more neuromuscular conditions in hemiplegic ankle-foot dysfunction from different aspects. TRIAL REGISTRATION: ChiCTR2100055090.
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Tobillo , Electromiografía , Pie , Músculo Esquelético , Accidente Cerebrovascular , Humanos , Masculino , Músculo Esquelético/fisiopatología , Pie/fisiopatología , Tobillo/fisiopatología , Persona de Mediana Edad , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/fisiopatología , Hemiplejía/fisiopatología , Hemiplejía/etiología , Adulto , AncianoRESUMEN
BACKGROUND: A given movement requires precise coordination of multiple muscles under the control of center nervous system. However, detailed knowledge about the changing characteristics of neuromuscular control for multi-muscle coordination in post-stroke hemiplegic patients during standing is still lacking. This study aimed to investigate the hemiplegia-linked neuromuscular dysfunction during standing from the perspective of multi-muscle dynamical coordination by utilizing a novel network approach - weighted recurrence network (WRN). METHODS: Ten male hemiplegic patients with first-ever stroke and 10 age-matched healthy male adults were instructed to stand on a platform quietly for 30 s with eyes opened and eyes closed, respectively. The WRN was constructed based on the surface electromyography signals of 16 muscles from trunk, hips, thighs and calves. Relevant topological parameters, including clustering coefficient (C) and average shortest path length (L), were extracted to evaluate the dynamical coordination of multiple muscles. A measure of node centrality in network theory, degree of centrality (DC), was innovatively introduced to assess the contribution of single muscle in the multi-muscle dynamical coordination. The standing-related assessment metric, center of pressure (COP), was provided by the platform directly. RESULTS: Results showed that the post-stroke hemiplegic patients stood with remarkably higher similarity of muscle activation and more coupled intermuscular dynamics, characterized by higher C and lower L than the healthy subjects (p < 0.05). The DC values and rankings of back, hip and calf muscles on the affected side were significantly decreased, whereas those on the unaffected side were significantly increased in hemiplegia group compared with the healthy group (p < 0.05). Without visual feedback, subjects exhibited enhanced muscle coordination and increased muscle involvement (p < 0.05). A decrease in C and an increase in L of WRN were observed with decreased COP areas (p < 0.05). CONCLUSIONS: These findings revealed that stroke-induced hemiplegia could significantly influence the neuromuscular control, which was manifested as more coupled intermuscular dynamics, abnormal deactivation of muscles on affected side and compensation of muscles on unaffected side from the perspective of multi-muscle coordination. Enhanced multi-muscle dynamical coordination was strongly associated with impaired postural control. This study provides a novel analytical tool for evaluation of neuromuscular dysfunction and specification of responsible muscles for impaired postural control in stroke-induced hemiplegic patients, and could be potentially applied in clinical practice.
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Electromiografía , Hemiplejía , Músculo Esquelético , Accidente Cerebrovascular , Humanos , Hemiplejía/etiología , Hemiplejía/fisiopatología , Masculino , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/fisiopatología , Persona de Mediana Edad , Músculo Esquelético/fisiopatología , Posición de Pie , Equilibrio Postural/fisiología , Anciano , AdultoRESUMEN
AIMS: To investigate the level of spiritual health in older patients with chronic obstructive pulmonary disease (COPD) from the core dimensions and to explore its associated factors. DESIGN: A cross-sectional study. METHODS: Participants were recruited from four hospitals between September 2020 and June 2021, using a convenience sampling. Older patients with COPD (n = 162) completed the demographic and disease-related information questionnaires, Function Assessment of Chronic Illness Therapy Spiritual Scale, 10-item Connor-Davidson Resilience Scale, General Self-efficacy Scale, Social Support Rating Scale, COPD Assessment Test, 15-item Geriatric Depression Scale and modified Medical Research Council Dyspnea Scale. Descriptive statistics, Pearson and Spearman correlation analyses, t-tests, one-way ANOVA and multiple linear regression models were used. RESULTS: Older patients with COPD have a moderate level of spiritual health. The multiple linear regression analysis showed that psychological resilience, general self-efficacy, social support, symptom burden and monthly income were associated with the core dimensions of spiritual health. CONCLUSION: Chinese older patients with COPD have a moderate level of spiritual health. Psychological resilience, general self-efficacy, social support, monthly income and symptom burden were associated with the core dimensions of spiritual health. IMPACT: This study is the first to investigate the level of spiritual health in older patients with COPD from the core dimensions and to explore its associated factors, providing a basis for developing spiritual intervention programs. Our findings can help us realize that intervention strategies of psychological resilience, general self-efficacy and social support can all be used to enhance spiritual health. Nurses should focus on the spiritual health of older COPD patients with high symptom burden and low monthly income. PATIENT OR PUBLIC CONTRIBUTION: Although we did not directly involve patients and the public because of the COVID-19 pandemic, the results of the study will be disseminated to patients and the public through WeChat and seminars.
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Enfermedad Pulmonar Obstructiva Crónica , Resiliencia Psicológica , Humanos , Anciano , Estudios Transversales , Pandemias , Encuestas y Cuestionarios , Calidad de Vida/psicologíaRESUMEN
Sweet sorghum, as a seasonal energy crop, is rich in cellulose and hemicellulose that can be converted into biofuels. This work aims at investigating the effects of synergistic regulation of Pichia anomala and cellulase on ensiling quality and microbial community of sweet sorghum silages as a storage and pretreatment method. Furthermore, the combined pretreatment effects of ensiling and ball milling on sweet sorghum were evaluated by microstructure change and enzymatic hydrolysis. Based on membership function analysis, the combination of P. anomala and cellulase (PA + CE) significantly improved the silage quality by preserving organic components and promoting fermentation characteristics. The bioaugmented ensiling with PA + CE restructured the bacterial community by facilitating Lactobacillus and inhibiting undesired microorganisms by killer activity of P. anomala. The combined bioaugmented ensiling pretreatment with ball milling significantly increased the enzymatic hydrolysis efficiency (EHE) to 71%, accompanied by the increased specific surface area and decreased pore size/crystallinity of sweet sorghum. Moreover, the EHE after combined pretreatment was increased by 1.37 times compared with raw material. Hence, the combined pretreatment was demonstrated as a novel strategy to effectively enhance enzymatic hydrolysis of sweet sorghum.
Asunto(s)
Celulasa , Saccharomycetales , Sorghum , Hidrólisis , Sorghum/química , Sorghum/metabolismo , Ensilaje/análisis , Ensilaje/microbiología , Celulasa/metabolismo , FermentaciónRESUMEN
BACKGROUND: Leucine (Leu) is an essential amino acid that facilitates skeletal muscle satellite cell differentiation, yet its mechanism remains underexplored. Sestrin2 (SESN2) serves as a Leu sensor, binding directly to Leu, while ribophorin II (RPN2) acts as a signaling factor in multiple pathways. This study aimed to elucidate Leu's impact on mouse C2C12 cell differentiation and skeletal muscle injury repair by modulating RPN2 expression through SESN2, offering a theoretical foundation for clinical skeletal muscle injury prevention and treatment. RESULTS: Leu addition promoted C2C12 cell differentiation compared to the control, enhancing early differentiation via myogenic determinant (MYOD) up-regulation. Sequencing revealed SESN2 binding to and interacting with RPN2. RPN2 overexpression up-regulated MYOD, myogenin and myosin heavy chain 2, concurrently decreased p-GSK3ß and increased nuclear ß-catenin. Conversely, RPN2 knockdown yielded opposite results. Combining RPN2 knockdown with Leu rescued increased p-GSK3ß and decreased nuclear ß-catenin compared to Leu absence. Hematoxylin and eosin staining results showed that Leu addition accelerated mouse muscle damage repair, up-regulating Pax7, MYOD and RPN2 in the cytoplasm, and nuclear ß-catenin, confirming that the role of Leu in muscle injury repair was consistent with the results for C2C12 cells. CONCLUSION: Leu, bound with SESN2, up-regulated RPN2 expression, activated the GSK3ß/ß-catenin pathway, enhanced C2C12 differentiation and expedited skeletal muscle damage repair. © 2024 Society of Chemical Industry.