RESUMEN
Dysfunction of the tumor suppressor p53 occurs in most human cancers, Hdm2 and HdmX play critical roles in p53 inactivation and degradation. Under unstressed conditions, HdmX binds to p53 like Hdm2, but HdmX cannot directly induce p53 degradation. Moreover, HdmX has been reported to stimulate Hdm2-mediated ubiquitination and degradation of p53. Here we reported that HdmX promoted the nuclear export of p53 independent of Hdm2 in living cells using FRET technology. Whereas, Hdm2 impeded HdmX-mediated nuclear export of p53 by sequestering it in nucleus. Interestingly, the C-terminal RING domain mutant Hdm2C464A formed heterooligomers with p53 in nucleus, which was inhibited by HdmX. The heterooligomers were located near PML-NBs. This study indicate that the nuclear Hdm2-HdmX interaction aborts the HdmX-mediated nuclear export of p53.
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Transporte Activo de Núcleo Celular , Proteínas de Ciclo Celular , Núcleo Celular , Proteínas Proto-Oncogénicas c-mdm2 , Proteínas Proto-Oncogénicas , Proteína p53 Supresora de Tumor , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Humanos , Núcleo Celular/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Ubiquitinación , Unión ProteicaRESUMEN
Promyelocytic leukemia protein (PML), a tumor suppressor protein, plays a key role in cell cycle regulation, apoptosis, senescence and cellular metabolism. Here, we report that PML promotes apoptosis and ferroptosis. Our data showed that PML over-expression inhibited cell proliferation and migration. PML over-expression increased apoptotic cells, nuclear condensation and the loss of mitochondrial membrane potential, accompanied by regulation of Bcl-2 family proteins and reactive oxygen species (ROS) level, suggesting that PML enhanced apoptosis. Meanwhile, PML over-expression not only increased lipid ROS accumulation and Malondialdehyde (MDA) content but also downregulated solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) expression, indicating that PML enhanced ferroptosis. Additionally, knockdown of p53 attenuated the effect of PML on SLC7A11 and GPX4, and inhibited the increase of lipid ROS and ROS by PML over-expression. Moreover, translocation of PML from nucleus to cytoplasm not only promoted apoptosis and ferroptosis, but also inhibited cell proliferation. Taken together, PML promotes apoptosis and ferroptosis, in which the mediation of p53 and the nuclear export of PML play important roles.
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Transporte Activo de Núcleo Celular , Sistema de Transporte de Aminoácidos y+ , Apoptosis , Proliferación Celular , Ferroptosis , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Proteína de la Leucemia Promielocítica , Proteína p53 Supresora de Tumor , Humanos , Sistema de Transporte de Aminoácidos y+/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Línea Celular Tumoral , Movimiento Celular , Núcleo Celular/metabolismo , Potencial de la Membrana Mitocondrial , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Proteína de la Leucemia Promielocítica/metabolismo , Proteína de la Leucemia Promielocítica/genética , Especies Reactivas de Oxígeno/metabolismo , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Yes-associated protein (YAP)-a major effector protein of the Hippo pathway- regulates cell proliferation, differentiation, apoptosis, and senescence. Amp-activated protein kinase (AMPK) is a key sensor that monitors cellular nutrient supply and energy status. Although YAP and AMPK are considered to regulate cellular senescence, it is still unclear whether AMPK is involved in YAP-regulated cellular senescence. Here, we found that YAP promoted AMPKα1 aggregation and localization around mitochondria by co-transfecting CFP-YAP and YFP-AMPKα1 plasmids. Subsequent live cell fluorescence resonance energy transfer (FRET) assay did not exhibit direct interaction between YAP and AMPKα1. FRET, Co-immunoprecipitation, and western blot experiments revealed that YAP directly bound to TEAD, enhancing the expression of AMPKα1 and p-AMPKα. Treatment with verteporfin inhibited YAP's binding to TEAD and reversed the elevated expression of AMPKα1 in the cells overexpressing CFP-YAP. Verteporfin also reduced the proportion of AMPKα1 puncta in the cells co-expressing CFP-YAP and YFP-AMPKα1. In addition, the AMPKα1 puncta were demonstrated to inhibit cell viability, autophagy, and proliferation, and ultimately promote cell senescence. In conclusion, YAP binds to TEAD to upregulate AMPKα1 and promotes the formation of AMPKα1 puncta around mitochondria under the condition of co-expression of CFP-YAP and YFP-AMPKα1, in which AMPKα1 puncta lead to cellular senescence.
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Neoplasias , Factores de Transcripción , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Quinasas Activadas por AMP , Verteporfina , Senescencia Celular , Diferenciación Celular , Proliferación CelularRESUMEN
Cryptococcus neoformans poses a threat to human health, but anticryptococcal therapy is hampered by the emergence of drug resistance, whose underlying mechanisms remain poorly understood. Herein, we discovered that Isw1, an imitation switch chromatin remodeling ATPase, functions as a master modulator of genes responsible for in vivo and in vitro multidrug resistance in C. neoformans. Cells with the disrupted ISW1 gene exhibited profound resistance to multiple antifungal drugs. Mass spectrometry analysis revealed that Isw1 is both acetylated and ubiquitinated, suggesting that an interplay between these two modification events exists to govern Isw1 function. Mutagenesis studies of acetylation and ubiquitination sites revealed that the acetylation status of Isw1K97 coordinates with its ubiquitination processes at Isw1K113 and Isw1K441 through modulating the interaction between Isw1 and Cdc4, an E3 ligase. Additionally, clinical isolates of C. neoformans overexpressing the degradation-resistant ISW1K97Q allele showed impaired drug-resistant phenotypes. Collectively, our studies revealed a sophisticated acetylation-Isw1-ubiquitination regulation axis that controls multidrug resistance in C. neoformans.
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Criptococosis , Cryptococcus neoformans , Proteínas de Saccharomyces cerevisiae , Humanos , Cromatina , Cryptococcus neoformans/genética , Saccharomyces cerevisiae/genética , Acetilación , Conducta Imitativa , Adenosina Trifosfatasas/metabolismo , Ubiquitinación , Resistencia a Múltiples Medicamentos , Proteínas de Unión al ADN/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
In this work, a N/P polySi thermopile-based gas flow device is presented, in which a microheater distributed in a comb-shaped structure is embedded around hot junctions of thermocouples. The unique design of the thermopile and the microheater effectively enhances performance of the gas flow sensor leading to a high sensitivity (around 6.6 µV/(sccm)/mW, without amplification), fast response (around 35 ms), high accuracy (around 0.95%), and mood long-term stability. In addition, the sensor has the advantages of easy production and compact size. With such characteristics, the sensor is further used in real-time respiration monitoring. It allows detailed and convenient collection of respiration rhythm waveform with sufficient resolution. Information such as respiration periods and amplitudes can be further extracted to predict and alert of potential apnea and other abnormal status. It is expected that such a novel sensor could provide a new approach for respiration monitoring related noninvasive healthcare systems in the future.
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BACKGROUND: The acute effect during positive pressure titration and long term efficacy of acetazolamide (AZT) in high loop gain sleep apnea (HLGSA) is inadequately assessed. We predicted that AZT may improve HLGSA in both conditions. METHODS: A retrospective analysis of polysomnograms from patients with presumed HLGSA and residual respiratory instability administered AZT (125 or 250 mg) about 3 h into an initially drug-free positive pressure titration. A responder was defined as ≥ 50% reduction of the apnea hypopnea index(AHI 3% or arousal) before and after AZT. A multivariable logistic regression model estimated responder predictors. Long term efficacy of AZT was assessed by comparing both auto-machine (aREIFLOW) and manually scored respiratory events (sREIFLOW) extracted from the ventilator, prior to and after 3 months of AZT, in a subset. RESULTS: Of the 231 participants (median age of 61[51-68] years) and 184 (80%) males in the acute effect testing: 77 and 154 patients were given 125 mg and 250 mg AZT. Compared to PAP alone, PAP plus AZT was associated with a lower breathing related arousal index (8 [3-16] vs. 5 [2-10], p < 0.001), and AHI3% (19 [7-37] vs. 11 [5-21], p < 0.001); 98 patients were responders. The non-rapid eye movement sleep (NREM) AHI3% (OR 1.031, 95%CI [1.016-1.046], p < 0.001) was a strong predictor for responder status with AZT exposure. In the 109 participants with 3-month data, both aREIFLOW and sREIFLOWwere significantly reduced after AZT. CONCLUSIONS: AZT acutely and chronically reduced residual sleep apnea in presumed HLGSA; NREM AHI3% is a response predictor. AZT was well tolerated and beneficial for at least 3 months.
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Síndromes de la Apnea del Sueño , Apnea Obstructiva del Sueño , Masculino , Humanos , Persona de Mediana Edad , Anciano , Femenino , Acetazolamida/farmacología , Acetazolamida/uso terapéutico , Apnea Obstructiva del Sueño/tratamiento farmacológico , Estudios Retrospectivos , Síndromes de la Apnea del Sueño/tratamiento farmacológico , Respiración , Presión de las Vías Aéreas Positiva ContínuaRESUMEN
BACKGROUND: The significance of systemic chemotherapy (SCT) combined with hepatic arterial infusion (HAI) chemotherapy in the treatment of pancreatic ductal adenocarcinoma with liver metastases (PACLM) remains unclear. Based on previous studies, this single-center propensity score matching (PSM) study aimed to explore the efficacy of SCT with or without HAI for PACLM. PATIENT AND METHODS: The PSM method was used to screen 661 cases of PACLM who received SCT at Tianjin Medical University Cancer Institute and Hospital from 2001 to 2020. According to the 1:6 ratio with PSM, 385 patients were divided into the SCT+HAI group (n = 55) and the SCT group (n = 330). After a median follow-up of 49 (range 7-153) months, overall survival (OS) and survival-related prognostic factors were analyzed. RESULTS: The main baseline characteristics of the SCT+HAI group and the SCT alone group were matched appropriately (P > .05). After PSM, the median OS for patients in the 2 groups was 10.6 and 7.6 months, respectively (P = .02). Multivariate analysis revealed that peritoneal metastases (P = .03), CA199 ≥ 500U/mL (P = .03), and lactate dehydrogenase (LDH) ≥ 250U/L (P = .03) were prognostic factors of poor survival, modern SCT plus HAI (P = .04) was a protective factor. CONCLUSION: Our findings indicated that adequate cycles of SCT+HAI result in better survival than SCT alone in patients with PACLM. Patients with peritoneal metastases, markedly elevated CA19-9 and LDH have a poorer prognosis. The conclusion has yet to be validated in randomized controlled clinical trials.
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Neoplasias Colorrectales , Neoplasias Hepáticas , Neoplasias Pancreáticas , Neoplasias Peritoneales , Humanos , Neoplasias Peritoneales/tratamiento farmacológico , Puntaje de Propensión , Neoplasias Colorrectales/patología , Infusiones Intraarteriales , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Neoplasias Hepáticas/secundario , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Arteria Hepática/patología , Neoplasias PancreáticasRESUMEN
Mitochondrial quality control prevents accumulation of intramitochondrial-derived reactive oxygen species (mtROS), thereby protecting cells against DNA damage, genome instability, and programmed cell death. However, underlying mechanisms are incompletely understood, particularly in fungal species. Here, we show that Cryptococcus neoformans heat shock factor 3 (CnHsf3) exhibits an atypical function in regulating mtROS independent of the unfolded protein response. CnHsf3 acts in nuclei and mitochondria, and nuclear- and mitochondrial-targeting signals are required for its organelle-specific functions. It represses the expression of genes involved in the tricarboxylic acid cycle while promoting expression of genes involved in electron transfer chain. In addition, CnHsf3 responds to multiple intramitochondrial stresses; this response is mediated by oxidation of the cysteine residue on its DNA binding domain, which enhances DNA binding. Our results reveal a function of HSF proteins in regulating mtROS homeostasis that is independent of the unfolded protein response.
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Cryptococcus neoformans , Cisteína , Cryptococcus neoformans/genética , Cryptococcus neoformans/metabolismo , Cisteína/metabolismo , ADN/metabolismo , Homeostasis , Mitocondrias/genética , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismoRESUMEN
BACKGROUND: This study aimed to summarize the association between diabetes mellitus (DM) and the incidence of lung cancer using a meta-analysis of cohort studies. MATERIALS AND METHODS: We systematically searched PubMed, Embase and the Cochrane Library to identify potential cohort studies. Relative risk (RR) was used to calculate the association between DM and the risk of lung cancer. Subgroup analysis, sensitivity analysis and test for publication bias were performed. Twenty cohort studies were selected. RESULTS: The participants with DM showed little or no significant effect on the risk of lung cancer (RR: 1.10; 95% CI: 0.99-1.23; P = .087). DM was not associated with the risk of lung cancer in men (RR: 1.11; 95%CI: 0.92-1.35; P = .270), but a significant association was observed in women (RR: 1.18; 95%CI: 1.10-1.28; P < .001). Subgroup analysis suggested that smoker status was confounding variables that could bias the relationship between DM and the incidence of lung cancer. CONCLUSIONS: This meta-analysis suggests that DM has no significant impact on the incidence of lung cancer in men but has a harmful effect on women.
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Diabetes Mellitus/epidemiología , Neoplasias Pulmonares/epidemiología , HumanosRESUMEN
BACKGROUND: Studies investigating the role of hyperoxia in critically ill patients have reported conflicting results. We did this analysis to reveal the effect of hyperoxia in the patients admitted to the intensive care unit (ICU). METHODS: Electronic databases were searched for all the studies exploring the role of hyperoxia in adult patients admitted to ICU. The primary outcome was mortality. Random-effect model was used for quantitative synthesis of the adjusted odds ratio (aOR). RESULTS: We identified 24 trials in our final analysis. Statistical heterogeneity was found between hyperoxia and normoxia groups in patients with mechanical ventilation (I2 = 92%, P < 0.01), cardiac arrest(I2 = 63%, P = 0.01), traumatic brain injury (I2 = 85%, P < 0.01) and post cardiac surgery (I2 = 80%, P = 0.03). Compared with normoxia, hyperoxia was associated with higher mortality in overall patients (OR 1.22, 95% CI 1.12~1.33), as well as in the subgroups of cardiac arrest (OR 1.30, 95% CI 1.08~1.57) and extracorporeal life support (ELS) (OR 1.44, 95% CI 1.03~2.02). CONCLUSIONS: Hyperoxia would lead to higher mortality in critically ill patients especially in the patients with cardiac arrest and ELS.
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Enfermedad Crítica/mortalidad , Mortalidad Hospitalaria , Hiperoxia/epidemiología , Lesiones Traumáticas del Encéfalo/mortalidad , Procedimientos Quirúrgicos Cardíacos/estadística & datos numéricos , Oxigenación por Membrana Extracorpórea/estadística & datos numéricos , Paro Cardíaco/mortalidad , Humanos , Hiperoxia/etiología , Unidades de Cuidados Intensivos , Mortalidad , Oportunidad Relativa , Terapia por Inhalación de Oxígeno/efectos adversos , Periodo Posoperatorio , Respiración Artificial/estadística & datos numéricosRESUMEN
OBJECTIVE: To observe the effect of elongated-needle penetration (ENP) stimulation of "Zhibian" (BL 54), "Shuidao" (ST 28), "Qihai" (CV 6) and "Zhongji" (CV 3) on spinal nerve cell apoptosis and cellular signal transduction in spinal cord injury rabbits, so as to reveal its mechanism underlying improvement of spinal injury. METHODS: A total of 80 adult Newzealand rabbits were randomized to control, model, ENP, ENP + LY 294002 (PI3K antagonist), ENP + PD 98059 (MEK antagonist) groups, with 16 rabbits in each group. The spinal cord injury model was established by using modified Allen's method (Gravity-drop device). Elongated-needle penetration was applied to bilateral BL 54, ST 28, CV 3 and CV 6, once daily for 3 times. For rabbits of the ENP+ LY 294002 and ENP+ PD 98059 groups, LY 294002 (10 microg, 20 microL), PD 98059 (3 microg, 20 microL) were separately given by intrathecal injection. Pathomorphological changes of the injured spinal cord (T13-L1) were observed after H.E. stain. Spinal cell apoptosis was detected by TUNEL,and phosphorylated (p)-Akt and p-ERK1/2 immunoactivity was detected by immunohistochemistry, and the expression levels of p-Akt, p-ERK1/2, cytochrome C (Cyt C) and Caspase-3 proteins were determined by Western blot (WB), and serum TNF-alpha content was assayed by ELISA. RESULTS: H. E. staining showed apparent structural changes as hemmorrhage, inflammatory cell infiltration, cellular edema and necrosis, and formation of vacuolation in the spinal cord in the model group, which was marked milder in the ENP group. TUNEL assay showed that the rate of apoptotic cells was notably increased in the model group than in the control group (P < 0.05), obviously decreased in the ENP group when compared with the model group (P < 0.05). Immunohistochemistry, WB and ELISA results showed that compared with the control group, spinal p-Akt and p-ERK1/2 protein expression levels in the model group were significantly decreased (P < 0.05), and Cyt C and Caspase-3 expression levels and serum TNF-a content were significantly increased in the model group (P < 0.05). Compared with the model group, the expression levels of p-Akt, p-ERK1/2 were significantly increased in the ENP group (P < 0.05), while Cyt C and Caspase-3 expression levels and TNF-alpha content were significantly down-regulated in the ENP group (P < 0.05). After intrathecal injection of PI3K and MEK antagonists, the effects of ENP were significantly weakened in reducing apoptosis rate, upregulating p-Akt and p-ERK1/2 expression and in down-regulating Cyt C and Caspase-3 expression and TNF-alpha content (P < 0.05), suggesting important roles of ERK1/2 mediated extracellular and PI3K/Akt mediated intracellular apoptotic signal transduction pathways in ENP induced repair of the traumatic tissues. CONCLUSION: ENP stimulation can decrease spinal injury and cell apoptosis in spinal injury rabbits, which may be closely related to its effects in up-regulating p-Akt and p-ERK1/2 and down-regulating Cyt C and Caspase-3 expression levels in the spinal cord and serum TNF-alpha content.
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Terapia por Acupuntura , Apoptosis , Transducción de Señal , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/terapia , Terapia por Acupuntura/instrumentación , Animales , Caspasa 3/genética , Caspasa 3/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Agujas , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Conejos , Traumatismos de la Médula Espinal/genética , Traumatismos de la Médula Espinal/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
OBJECTIVE: To study the clinical efficacy of the endobutton in the treatment of acute acromioclavicular joint dislocation by reconstructing coracoclavicular ligaments. METHODS: From October 2008 to January 2010,12 patients with acute acromioclavicular joint dislocation were immobilized with the endobutton. All the patients had the dislocations of or above type III according to Rockwood classification. Among the patients, 9 patients were male and 3 patients were female, with an average age of 55 years (ranged from 31 to 83 years). Eight patients had injuries in the left, and 4 patients in the right. Four patients had accompanied injuries of rib fractures, 2 patients had brain injuries,and 1 patient had femoral fracture. Seven patients were injured by traffic accident, 4 patients were injured by falling down,and 1 patient was sports injuries. All the patients had pain and tenderness at the shoulder, positive piano sign, and shoulder confined activity. The duration from injury to operation ranged from 2 days to 10 days (averaged 6 days). The therapeutic effects were evaluated by Karlsson criteria based on range of motion of acromioclavicular joint, subjective feeling,and postoperative X-ray. RESULTS: All the patients were followed up, and the duration ranged from 4 months to 19 months (averaged 11 months). The motion of the shoulder joint recovered to normal about 15 to 35 days after operation. There were no displacement, dislocation and redislocation occurred. All the patients got A degree results according to Karlsson criteria. CONCLUSION: Reconstruction of coracoclavicular ligament by using the endobutton to treat acute acromioclavicular dislocation of or above type III is a perfect method with advantage of rigid fixation, micro-injury, and early functional exercise.
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Articulación Acromioclavicular/lesiones , Fijadores Externos , Luxaciones Articulares/cirugía , Procedimientos Ortopédicos/instrumentación , Articulación Acromioclavicular/diagnóstico por imagen , Articulación Acromioclavicular/fisiopatología , Articulación Acromioclavicular/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/fisiopatología , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
The cyclin-dependent kinases (CDKs) are critical regulators of cell cycle progression, and are involved in uncontrolled cell proliferation-a hallmark of cancer. This suggests that small molecular inhibitors of CDKs might be attractive as prospective antitumor agents. To explore the relationship between the structures of substituted isoquinoline-1,3-(2H,4H)-diones and their inhibition of CDK4, 3D-QSAR studies were performed on a dataset of 48 compounds. The bioactive conformation of template compound 34 was obtained by performing molecular docking into the ATP binding site of the homology model of CDK4 and ranking by highest consensus score, which was then used to build and align the rest of the molecules in the series. The constructed comparative molecular similarity indices analysis (CoMSIA) produces significantly better results than comparative molecular field analysis (CoMFA), with r(2)(cv) = 0.707 and r(2) = 0.988. The contours analysis provides useful information about the structural requirements for substituted isoquinoline-1,3-(2H,4H)-diones for CDK4 inhibitory activity.