RESUMO
Cyclic guanosine monophosphate (GMP)-AMP (cGAMP) synthase (cGAS) is a universal double-stranded DNA (dsDNA) sensor that recognizes foreign and self-DNA in the cytoplasm and initiates innate immune responses and has been implicated in various infectious and non-infectious contexts. cGAS binds to the backbone of dsDNA and generates the second messenger, cGAMP, which activates the stimulator of interferon genes (STING). Here, we show that the endogenous polyamines spermine and spermidine attenuated cGAS activity and innate immune responses. Mechanistically, spermine and spermidine induced the transition of B-form DNA to Z-form DNA (Z-DNA), thereby decreasing its binding affinity with cGAS. Spermidine/spermine N1-acetyltransferase 1 (SAT1), the rate-limiting enzyme in polyamine catabolism that decreases the cellular concentrations of spermine and spermidine, enhanced cGAS activation by inhibiting cellular Z-DNA accumulation; SAT1 deficiency promoted herpes simplex virus 1 (HSV-1) replication in vivo. The results indicate that spermine and spermidine induce dsDNA to adopt the Z-form conformation and that SAT1-mediated polyamine metabolism orchestrates cGAS activity.
Assuntos
DNA de Forma B , DNA Forma Z , Espermina/metabolismo , Espermidina/metabolismo , DNA/metabolismo , Nucleotidiltransferases/metabolismo , Poliaminas/metabolismo , Imunidade Inata/genéticaRESUMO
Cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS) detects cytoplasmic microbial DNA and self-DNA from genomic instability, initiates innate immunity, and plays fundamental roles in defense against viruses and the development of various diseases. The cellular cGAS level determines the magnitude of the response to DNA. However, the underlying mechanisms of the control of cGAS stability, especially its feedback regulation during viral infection, remain largely unknown. In this study, we show that viral infection induces the expression of the UAF1-USP1 deubiquitinase complex in primary peritoneal macrophages (PMs) of C57BL/6J mice. UAF1-USP interacts with cGAS, selectively cleaves its K48-linked polyubiquitination, and thus stabilizes its protein expression in PMs and HEK293T cells. Concordantly, the UAF1-USP1 deubiquitinase complex enhances cGAS-dependent type I IFN responses in PMs. Uaf1 deficiency and ML323 (a specific inhibitor of UAF1-USP1 deubiquitinase complex) attenuates cGAS-triggered antiviral responses and facilitates viral replication both in vitro and in vivo. Thus, our study uncovers a positive feedback mechanism of cGAS-dependent antiviral responses and suggests the UAF1-USP1 complex as a potential target for the treatment of diseases caused by aberrant cGAS activation.
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Proteases Específicas de Ubiquitina , Viroses , Animais , Humanos , Camundongos , Antivirais , DNA , Células HEK293 , Camundongos Endogâmicos C57BL , Proteínas Nucleares/genética , Nucleotidiltransferases/genética , Proteases Específicas de Ubiquitina/metabolismoRESUMO
Stimulator-of-interferon gene (STING) is a vital element of the innate immune system against DNA viruses. Optimal activation of STING is crucial for maintaining immune homeostasis and eliminating invading viruses, and the oligomerization of STING is an essential prerequisite for STING activation. However, the mechanism of cGAMP-induced STING oligomerization in ER remains unclear. Selenoproteins are crucial for various physiological processes. Here, we identified that the endoplasmic reticulum (ER)-located transmembrane selenoprotein K (SELENOK) was induced during virus infection and facilitated innate immune responses against herpes simplex virus-1 (HSV-1). Mechanistically, SELENOK interacts with STING in the ER and promotes STING oligomerization, which in turn promotes its translocation from the ER to the Golgi. Consequently, Selenok deficiency suppresses STING-dependent innate responses and facilitates viral replication in vivo. Thus, the control of STING activation by selenium-mediated SELENOK expression will be a priming therapeutic strategy for the treatment of STING-associated diseases.
Assuntos
Herpesvirus Humano 1 , Antivirais , Herpesvirus Humano 1/fisiologia , Imunidade Inata , Selenoproteínas , Replicação Viral/genética , Humanos , Animais , CamundongosRESUMO
Near-infrared fluorescence (NIRF) probes greatly facilitate in vivo imaging of various biologically important species. However, there are several significant limitations such as consuming washing steps, photobleaching, and low signal intensity. Herein, we synthesized fluorescent copper nanosheets templated with DNA scaffolds (DNS/CuNSs). We employ them and Cy5.5 of the fluorescence resonance energy transfer (FRET) system, which have a larger Stokes shift (â¼12-fold) than the traditional NIRF dye Cy5.5. Based on their excellent fluorescence properties, we employ DNS/CuNSs-Cy5.5 for fluorescence probes in cancer cell imaging. Compared with the free Cy5.5 fluorescence probe, the novel fluorescence imaging probe implements wash-free imaging and exhibits enhanced anti-photobleaching ability (â¼5.5-fold). Moreover, the FRET system constructed by DNS/CuNSs has a higher signal amplification ability (â¼4.17-fold), which is more similar to that of Cu nanoclusters prepared with DNA nanomonomers as a template. This work provides a new idea for cancer cell MCF-7 imaging and is expected to promote the development of cancer cell fluorescence imaging.
Assuntos
Carbocianinas , Cobre , Neoplasias , Transferência Ressonante de Energia de Fluorescência/métodos , Corantes Fluorescentes , Imagem Óptica , DNA , Neoplasias/diagnóstico por imagemRESUMO
Driven by the pressing demand for stable energy systems, zinc-air batteries (ZABs) have emerged as crucial energy storage solutions. However, the quest for cost-effective catalysts to enhance vital oxygen evolution and reduction reactions remains challenging. FeNiCo|MnGaOx heterostructure nanoparticles on carbon nanotubes (CNTs) are synthesized using liquid-phase reduction and H2 calcination approach. Compared to its component, such FeNiCo|MnGaOx/CNT shows a high synergistic effect, low impedance, and modulated electronic structure, leading to a superior bifunctional catalytic performance with an overpotential of 255 mV at 10 mA cm-2 and half-wave potential of 0.824 V (ω = 1600 rpm and 0.1 m KOH electrolyte). Moreover, ZABs based on FeNiCo|MnGaOx/CNT demonstrate notable features, including a peak power density of 136.1 mW cm-2, a high specific capacity of 808.3 mAh gZn -1, and outstanding stability throughout >158 h of uninterrupted charge-discharge cycling. Theoretical calculations reveal that the non-homogeneous interface can introduce more carriers and altered electronic structures to refine intermediate adsorption reactions, especially promoting O* formation, thereby enhancing electrocatalytic performance. This work demonstrates the importance of heterostructure interfacial modulation of electronic structure and enhancement of adsorption capacity in promoting the implementation of OER/ORR, ZABs, and related applications.
RESUMO
The role of inflammatory cytokines in children with moderate to severe TBI (m-sTBI) is still incompletely understood. We aimed to investigate the associations between early plasma expression profiles of inflammatory cytokines and clinical outcomes in children with m-sTBI. We prospectively recruited children admitted to the intensive care unit (ICU) of a tertiary pediatric hospital due to m-sTBI from November 2022 to May 2023. Plasma interleukin (IL)-1ß, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-17A, interferon (IFN)-α, IFN-γ and tumor necrosis factor (TNF)-α concentrations were detected by flow cytometry on admission and on days 5 to 7. The primary outcome was in-hospital mortality. The secondary outcome was the 6-month functional outcome assessed by the Glasgow Outcome Scale Extended-Pediatrics (GOS-E Peds) score, dichotomized as favorable (1-4) or unfavorable (5-8). Fifty patients and 20 healthy controls were enrolled. Baseline IL-6, IL-8 and IL-10 levels were significantly higher in TBI patients than in healthy controls. Twelve patients died in the hospital. Compared with survivors, nonsurvivors had significantly increased baseline IL-6 and IL-8 levels. Baseline IL-5, IL-6 and IL-8 levels were also significantly greater in children with unfavorable versus favorable outcomes. The area under the receiver operating characteristic curve (AUC) of the IL-6 and IL-8 levels and motor Glasgow Coma Scale (GCS) score for predicting in-hospital mortality was 0.706, 0.754, and 0.776, respectively. Baseline IL-1ß, IL-2, IL-4, IL-10, IL-12p70, IL-17A, IFN-γ, IFN-α and TNF-α levels were not associated with in-hospital mortality or an unfavorable 6-month outcome. On days 5 to 7, the IL-6 and IL-8 levels were significantly decreased in survivors but increased in nonsurvivors compared to their respective baselines. CONCLUSION: After m-sTBI, the plasma profiles of inflammatory cytokines are markedly altered in children. The trends of IL-6 and IL-8 expression vary among m-sTBI children with different outcomes. Elevated plasma IL-6 and IL-8 levels are related to in-hospital mortality and unfavorable 6-month outcomes. TRIAL REGISTRATION: This trial was registered in the Chinese Clinical Trial Registry (Registration number: ChiCTR2200065505). Registered November 7, 2022. WHAT IS KNOWN: ⢠Inflammation is an important secondary physiological response to TBI. WHAT IS NEW: ⢠The plasma profiles of inflammatory cytokines are markedly altered in children with m-sTBI. Elevated IL-6 and IL-8 levels are related to mortality and unfavorable outcomes.
Assuntos
Lesões Encefálicas Traumáticas , Citocinas , Humanos , Masculino , Feminino , Estudos Prospectivos , Criança , Citocinas/sangue , Lesões Encefálicas Traumáticas/sangue , Lesões Encefálicas Traumáticas/mortalidade , Pré-Escolar , Biomarcadores/sangue , Mortalidade Hospitalar , Estudos de Casos e Controles , Adolescente , Prognóstico , Lactente , Escala de Resultado de GlasgowRESUMO
Septic shock is a life-threatening disease worldwide often associated with thrombocytopenia. Platelets play a crucial role in bridging the gap between immunity, coagulation, and endothelial cell activation, potentially influencing the course of the disease. However, there are few studies specifically evaluating the impact of thrombocytopenia on the prognosis of pediatric patients. Therefore, the study investigates effects of early thrombocytopenia in the prognosis of children with septic shock. Pediatric patients with septic shock from 2015 to 2022 were included monocentrically. Thrombocytopenia was defined as a platelet count of <100 × 109/L during the first 24 hours of septic shock onset. The primary outcome was the 28-day mortality. Propensity score matching was used to pair patients with different platelet counts on admission but comparable disease severity. A total of 419 pediatric patients were included in the analysis. Patients with thrombocytopenia had higher 28-day mortality (55.5% vs. 38.7%, p = .005) compared to patients with no thrombocytopenia. Thrombocytopenia was associated with reduced 28-PICU free days (median value, 0 vs. 13 days, p = .003) and 28-ventilator-free (median value, 0 vs. 19 days, p = .001) days. Among thrombocytopenia patients, those with platelet count ≤50 × 109/L had a higher 28-day mortality rate (63.6% vs. 45%, p = .02). Multiple logistic regression showed that elevated lactate (adjusted odds ratio (OR) = 1.11; 95% confidence interval (CI): 1.04-1.17; P <0.001) and white blood cell (WBC) count (OR = 0.97; 95% CI: 0.95-0.99; p = .003) were independent risk factors for the development of thrombocytopenia. Thrombocytopenia group had increased bleeding events, blood product transfusions, and development of organ failure. In Kaplan-Meier survival estimates, survival probabilities at 28 days were greater in patients without thrombocytopenia (p value from the log-rank test, p = .004). There were no significant differences in the type of pathogenic microorganisms and the site of infection between patients with and without thrombocytopenia. In conclusion, thrombocytopenia within 24 hours of shock onset is associated with an increased risk of 28-day mortality in pediatric patients with septic shock.
What is the context? Septic shock is a life-threatening disease worldwide, leading to higher mortality.Platelets play a crucial role in bridging the gap between immunity, coagulation, and endothelial cell activation.Although it is known that platelets are associated with prognosis, most studies have focused on adult populations. Limited data are available on the incidence of thrombocytopenia and its correlation with clinical outcomes , specifically, in pediatric patients with sepsis and septic shock. What is new? The present study suggests that thrombocytopenia within 24 hours of septic shock onset reflects a reliable tool for predicting the prognosis of septic shock in pediatric patients.Furthermore, elevated lactate and reduced white-blood-cell count were independent risk factors for the development of thrombocytopenia in pediatric patients with septic shock. What is the impact? This study suggests that thrombocytopenia within 24 hours of septic shock onset is associated with an increased risk of 28-day mortality and decreased ventilation-free, PICU-free days in pediatric patients with septic shock. In septic shock, thrombocytopenia is also associated with increased bleeding events, blood product transfusions, and organ dysfunction.
Assuntos
Choque Séptico , Trombocitopenia , Humanos , Trombocitopenia/complicações , Trombocitopenia/sangue , Choque Séptico/complicações , Choque Séptico/mortalidade , Choque Séptico/sangue , Masculino , Feminino , Prognóstico , Estudos Retrospectivos , Criança , Pré-Escolar , Lactente , Contagem de Plaquetas/métodosRESUMO
BACKGROUND: Trauma-induced orbital blowout fracture (OBF) with eyeball displacement into the maxillary sinus is rare. CASE PRESENTATION: We present the case of a 14-year-old with a closed head injury, OBF, and displacement of the eyeball into the maxillary sinus following a car accident. A prompt transconjunctival access surgery was performed for eyeball repositioning and orbital reconstruction in a single session, mitigating anaesthesia-related risks associated with multiple surgeries. At the 12-month follow-up, his visual acuity was 20/200. Despite limited eye movement and optic nerve atrophy, overall satisfaction with the ocular appearance was achieved. CONCLUSIONS: This report offers novel insights into the mechanisms of OBF occurrence and the development of postoperative complications.
Assuntos
Traumatismos Cranianos Fechados , Transtornos da Motilidade Ocular , Fraturas Orbitárias , Masculino , Humanos , Adolescente , Seio Maxilar , Olho , Fraturas Orbitárias/complicações , Fraturas Orbitárias/diagnóstico , Fraturas Orbitárias/cirurgia , Traumatismos Cranianos Fechados/complicaçõesRESUMO
Acute colitis is a complex disease that can lead to dysregulation of the gut flora, inducing more complex parenteral diseases. Dandelion polysaccharides (DPSs) may have potential preventive and therapeutic effects on enteritis. In this study, LPS was used to induce enteritis and VC was used as a positive drug control to explore the preventive and therapeutic effects of DPS on enteritis. The results showed that DPS could repair the intestinal barrier, down-regulate the expression of TNF-α, IL-6, IL-1ß, and other pro-inflammatory factors, up-regulate the expression of IL-22 anti-inflammatory factor, improve the antioxidant capacity of the body, and improve the structure of intestinal flora. It is proved that DPS can effectively prevent and treat LPS-induced acute enteritis and play a positive role in promoting intestinal health.
Assuntos
Enterite , Microbioma Gastrointestinal , Taraxacum , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Lipopolissacarídeos , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , InflamaçãoRESUMO
While Catellani reactions have become increasingly important for arene functionalizations, they have been solely catalyzed by palladium. Here we report the first nickel-catalyzed Catellani-type annulation of aryl triflates and chlorides to form various benzocyclobutene-fused norbornanes in high efficiency. Mechanistic studies reveal a surprising outer-sphere concerted metalation/deprotonation pathway during the formation of the nickelacycle, as well as the essential roles of the base and the triflate anion. The reaction shows a broad functional group tolerance and enhanced regioselectivity compared to the corresponding palladium catalysis.
RESUMO
Two-dimensional (2D) amorphous materials could outperform their crystalline counterparts toward various applications because they have more defects and reactive sites and thus could exhibit a unique surface chemical state and provide an advanced electron/ion transport path. Nevertheless, it is challenging to fabricate ultrathin and large-sized 2D amorphous metallic nanomaterials in a mild and controllable manner due to the strong metallic bonds between metal atoms. Here, we reported a simple yet fast (10 min) DNA nanosheet (DNS)-templated method to synthesize micron-scale amorphous copper nanosheets (CuNSs) with a thickness of 1.9 ± 0.4 nm in aqueous solution at room temperature. We demonstrated the amorphous feature of the DNS/CuNSs by transmission electron microscopy (TEM) and X-ray diffraction (XRD). Interestingly, we found that they could transform to crystalline forms under continuous electron beam irradiation. Of note, the amorphous DNS/CuNSs exhibited much stronger photoemission (â¼62-fold) and photostability than dsDNA-templated discrete Cu nanoclusters due to the elevation of both the conduction band (CB) and valence band (VB). Such ultrathin amorphous DNS/CuNSs hold great potential for practical applications in biosensing, nanodevices, and photodevices.
Assuntos
Cobre , DNA , Replicação do DNA , Transporte de Elétrons , ElétronsRESUMO
The brain ischemia/reperfusion (I/R) injury has a great impact on human life and property safety. As far as we know, mild hypothermia (MH) is an effective measure to reduce neuronal injury after I/R. However, the precise mechanism is not extremely clear. The purpose of this study was to investigate whether mild therapeutic hypothermia can play a protective role in nerve cells dealing with brain I/R injury and explore its specific mechanism in vitro. A flow cytometer, cell counting kit-8 (CCK-8) assay and lactate dehydrogenase (LDH) release assay were performed to detect apoptotic rate of cells, cell viability and cytotoxicity, respectively, reactive oxygen species (ROS) assay kit, JC-1 fluorescent methods, immunofluorescence and western blot were used to explore ROS, mitochondrial transmembrane potential (Δψm), mitochondrial permeability transition pore (MPTP) and protein expression, respectively. The result indicated that the cell activity was decreased, while the cytotoxicity and apoptosis rate were increased after treating with oxygen-glucose deprivation/reperfusion (OGD/R) in PC12 cells. However, MH could antagonize this phenomenon. Interestingly, treating with OGD/R increased the release of ROS and the transfer of Cytochrome C (Cyt-C) from mitochondria to cytoplasm. In addition, it up-regulated the expression of γH2AX, Bax and Clv-caspase3, down-regulated the expression of PCNA, Rad51 and Bcl-2, and inhibited the function of mitochondria in PC12 cells. Excitingly, the opposite trend was observed after MH treatment. Therefore, our results suggest that MH protects PC12 cells against OGD/R-induced injury with the mechanism of inhibiting cell apoptosis by reducing ROS production, improving mitochondrial function, reducing DNA damage, and enhancing DNA repair.
Assuntos
Hipotermia , Traumatismo por Reperfusão , Animais , Ratos , Humanos , Oxigênio/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Células PC12 , Glucose/farmacologia , Hipotermia/metabolismo , Apoptose , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Reperfusão , Mitocôndrias/metabolismo , Dano ao DNARESUMO
Although tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of chronic myeloid leukaemia (CML), TKI resistance remains a major challenge. Here, we demonstrated that plant homeodomain finger protein 8 (PHF8), a histone demethylase was aberrantly enriched in CML samples compared to healthy controls. PHF8 inhibited CML cell differentiation and promoted CML cell proliferation. Furthermore, the proliferation-inhibited function of PHF8-knockdown have stronger effect on imatinib mesylate (IM)-resistant CML cells. Mechanistically, we identified that PHF8 as a transcriptional modulator interacted with the promoter of the BCR::ABL1 fusion gene and alters the methylation levels of H3K9me1, H3K9me2 and H3K27me1, thereby promoting BCR::ABL1 transcription. Overall, our study suggests that targeting PHF8, which directly regulates BCR::ABL1 expression, is a useful therapeutic approach for CML.
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Proteínas de Fusão bcr-abl , Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Apoptose , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Fusão bcr-abl/metabolismo , Histona Desmetilases/genética , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Fatores de Transcrição/genéticaRESUMO
Pancreatic cancer has a particularly poor prognosis compared to other tumors. The peculiar hyperinsulin microenvironment of the pancreas is formed due to the endocrine secretion of islets in the pancreas. This study focused on the effect of insulin on the migration and proliferation of pancreatic cancer cells and its molecular mechanisms. We found that insulin promotes the proliferation and migration of pancreatic cancer cells. At the same time, it can up-regulate the expression of PLK1 in pancreatic cancer cells. Knocking down the expression of PLK1 in pancreatic cancer cells can inhibit the effect of insulin on the biological behavior of pancreatic cancer. In addition, we found that insulin activates the PI3K/AKT pathway in pancreatic cancer cells, and that inhibition of this pathway suppresses PLK1 expression. The PI3K/AKT inhibitor LY294002 inhibits the effects of insulin on the proliferation of pancreatic cancer cells. This study shows that insulin up-regulates PLK1 expression in pancreatic cancer cells via the PI3K/AKT pathway, which in this way enhances the migration and proliferation of pancreatic cancer cells. This may be one of the important reasons for the poor prognosis of pancreatic cancer.
Assuntos
Insulina , Neoplasias Pancreáticas , Humanos , Insulina/farmacologia , Insulina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Proliferação de Células , Neoplasias Pancreáticas/patologia , Pâncreas/metabolismo , Linhagem Celular Tumoral , Microambiente Tumoral , Neoplasias PancreáticasRESUMO
BACKGROUND: Ferroptosis has excellent potential in glioblastoma (GBM) therapy. In this study, we attempted to explore the effect of miR 491-5p on ferroptosis in GBM. METHODS: In this study, publicly available ferroptosis-related genome maps were used to screen genes upregulated in GBM and their target genes. The Spearman correlation coefficient was applied to analyze the correlation between the tumor protein p53 gene (TP53) and miR-491-5p. The expressions of miR-491-5p and TP53 were determined. The protein abundances of the TP53-encoded factors p53 and p21 were measured. Cell proliferation, migration and invasion were assessed. We pretreated U251MG cells and GBM mice with a ferroptosis inducer (erastin). The mitochondrial state was observed. The contents of reactive oxygen species (ROS), total Fe and Fe2+ were calculated. RESULTS: The level of TP53 was significantly increased in GBM and negatively correlated with miR-491-5p. miR-491-5p overexpression promoted U251MG cell proliferation, migration and invasion and interfered with the p53/p21 pathway. TP53 supplement reversed the effects of miR-491-5p. U251MG cells and GBM mice exhibited significant accumulations of ROS and iron. Erastin promoted the expression of TP53. Inhibition of TP53 reversed erastin-induced physiological phenotypes. Moreover, miR-491-5p overexpression caused a decrease in the number of damaged mitochondria and the contents of ROS, total Fe and Fe2+. TP53 supplement disrupted miR-491-5p-repressed ferroptosis. Erastin could inhibit GBM growth, and miR-491-5p overexpression impeded the therapeutic effect of erastin. CONCLUSIONS: Our findings reveal the functional diversity of miR-491-5p in GBM and suggest that miR-491-5p/TP53 signaling hinders the sensitivity of GBM to ferroptosis through the p53/p21 pathway.
Assuntos
Neoplasias Encefálicas , Ferroptose , Glioblastoma , MicroRNAs , Animais , Camundongos , Glioblastoma/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Ferroptose/genética , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Neoplasias Encefálicas/patologia , Proliferação de Células , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão GênicaRESUMO
Cyclin-dependent kinase subunit 2 (CKS2) has been reported to promote various malignancies. This study investigated the functional role of CKS2 in pancreatic cancer (PC). An analysis of abnormally expressed genes and their prognostic value for PC was performed by using the Gene Expression Profiling Interactive Analysis (GEPIA) database and performing immunohistochemical staining on 64 samples of tumor tissue. CCK-8 assays, EdU staining, colony formation assays, flow cytometry, and a xenograft tumor model were used to analyze the biological function of CKS2 in PC. Our results revealed that CKS2 was expressed at significantly higher levels in PC tissues than in adjacent normal tissues, and a high level of CKS2 expression was associated with a poor prognosis for patients with PC. Moreover, functional assays revealed that CKS2 knockdown suppressed cell proliferation, induced cell cycle S phase, G2/M phase arrest, and apoptosis in vitro, and also reduced tumor growth in vivo. In addition, CKS2 knockdown increased the levels of Bax, caspase-3, P53, P21, and GADD45α expression, but decreased Bcl-2, Cyclin B1, CDK1, Cyclin A, and Cdc25C expression. CKS2 overexpression produced the opposite effects of CKS2 knockdown. Furthermore, we found that ELK1 protein regulated transcription of the CKS2 gene. In conclusion, our findings suggest that CKS2 expression is regulated by ELK1, which could possibly serve as prognostic indicator and therapeutic target for PC.
Assuntos
Quinases relacionadas a CDC2 e CDC28 , Neoplasias Pancreáticas , Humanos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Quinases relacionadas a CDC2 e CDC28/genética , Quinases relacionadas a CDC2 e CDC28/metabolismo , Proliferação de Células/genética , Fase G2 , Apoptose/genética , Neoplasias Pancreáticas/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Elk-1 do Domínio ets/genética , Proteínas Elk-1 do Domínio ets/metabolismo , Proteínas Elk-1 do Domínio ets/farmacologiaRESUMO
The regulation of microbial subpopulations in wastewater treatment plants (WWTPs) with desired functions can guarantee nutrient removal. In nature, "good fences make good neighbors," which can be applied to engineering microbial consortia. Herein, a membrane-based segregator (MBSR) was proposed, where porous membranes not only promote the diffusion of metabolic products but also isolate incompatible microbes. The MBSR was integrated with an anoxic/aerobic membrane bioreactor (i.e., an experimental MBR). The long-term operation showed that the experimental MBR exhibited higher nitrogen removal (10.45 ± 2.73 mg/L total nitrogen) than the control MBR (21.68 ± 4.23 mg/L) in the effluent. The MBSR resulted in much lower oxygen reduction potential in the anoxic tank of the experimental MBR (-82.00 mV) compared to that of the control MBR (83.25 mV). The lower oxygen reduction potential can inevitably aid in the occurrence of denitrification. The 16S rRNA sequencing showed that the MBSR significantly enriched acidogenic consortia, which yielded considerable volatile fatty acids by fermenting the added carbon sources and allowed efficient transfer of these small molecules to the denitrifying community. Moreover, the sludge communities of the experimental MBR harbored a higher abundance of denitrifying bacteria than those of the control MBR. Metagenomic analysis further corroborated these sequencing results. The spatially structured microbial communities in the experimental MBR system demonstrate the practicability of the MBSR, achieving nitrogen removal efficiency superior to that of mixed populations. Our study provides an engineering method for modulating the assembly and metabolic division of labor of subpopulations in WWTPs. IMPORTANCE This study provides an innovative and applicable method for regulating subpopulations (activated sludge and acidogenic consortia), which contributes to the precise control of the metabolic division of labor in biological wastewater treatment processes.
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Esgotos , Águas Residuárias , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Desnitrificação , Nitrogênio/metabolismo , RNA Ribossômico 16S/metabolismo , Bactérias , Reatores Biológicos/microbiologia , Oxigênio/metabolismo , Membranas ArtificiaisRESUMO
In this study, (1 + 1) × 1 side-pump couplers made of tellurite fibers were fabricated and investigated. The whole optical design of the coupler was established on the basis of ray tracing models and validated by experimental results. By optimizing the preparation conditions and structural parameters, the tested component achieved a coupling efficiency of 67.52% and an insertion loss of 0.52â dB. To the best of our knowledge, this is the first time a tellurite-fiber-based side-pump coupler was developed. The fused coupler presented will simplify many mid-infrared fiber lasers or amplifier architectures.
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Hemerocallis citrina Baroni is an edible plant with anti-inflammatory, antidepressant, and anticancer activities. However, studies on H. citrina polysaccharides are limited. In this study, a polysaccharide named HcBPS2 was isolated and purified from H. citrina. Monosaccharide component analysis showed that HcBPS2 was composed of rhamnose, arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid. Notably, HcBPS2 significantly inhibited human hepatoma cell proliferation, but had little effect on human normal liver cells (HL-7702). Mechanism investigations indicated HcBPS2 suppressed human hepatoma cell growth through the induction of G2/M phase arrest and mitochondria-dependent apoptosis in human hepatoma cells. In addition, the data revealed that HcBPS2 treatment led to the inactivation of Wnt/ß-catenin signaling, which then gave rise to cell cycle arrest and apoptosis in human hepatoma cancer cells. Collectively, these findings suggested that HcBPS2 may serve as a therapeutic agent against liver cancer.
Assuntos
Carcinoma Hepatocelular , Hemerocallis , Neoplasias Hepáticas , Humanos , beta Catenina , Carcinoma Hepatocelular/tratamento farmacológico , Proliferação de Células , Neoplasias Hepáticas/tratamento farmacológico , Polissacarídeos/farmacologia , Via de Sinalização Wnt/efeitos dos fármacosRESUMO
Aspergillus oryzae HML366 is a newly screened cellulase-producing strain. The endoglucanase HML ED1 from A. oryzae HML366 was quickly purified by a two-step method that combines ammonium sulfate precipitation and strong anion exchange column. SDS-PAGE electrophoresis indicated that the molecular weight of the enzyme was 68 kDa. The optimum temperature of the purified endoglucanase was 60 â and the enzyme activity was stable below 70 â. The optimum pH was 6.5, and the enzyme activity was stable at pH between 4.5 and 9.0. The analysis indicated that additional Na+, K+, Ca2+, and Zn2+ reduced the catalytic ability of enzyme to the substrate, but Mn2+ enhanced its catalytic ability to the substrate.The Km and Vmax of the purified endoglucanase were 8.75 mg/mL and 60.24 µmol/min·mg, respectively. In this study, we report for the first time that A. oryzae HML366 can produce a heat-resistant and wide pH tolerant endoglucanase HML ED1, which has potential industrial application value in bioethanol, paper, food, textile, detergent, and pharmaceutical industries.