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BACKGROUND: Intracellular Ca2+ cycling determines myocardial contraction and relaxation in response to physiological demands. SERCA2a (sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 2a) is responsible for the sequestration of cytosolic Ca2+ into intracellular stores during cardiac relaxation, and its activity is reversibly inhibited by PLN (phospholamban). However, the regulatory hierarchy of SERCA2a activity remains unclear. METHODS: Cardiomyocyte-specific ZBTB20 knockout mice were generated by crossing ZBTB20flox mice with Myh6-Cre mice. Echocardiography, blood pressure measurements, Langendorff perfusion, histological analysis and immunohistochemistry, quantitative reverse transcription-PCR, Western blot analysis, electrophysiological measurements, and chromatin immunoprecipitation assay were performed to clarify the phenotype and elucidate the molecular mechanisms. RESULTS: Specific ablation of ZBTB20 in cardiomyocyte led to a significant increase in basal myocardial contractile parameters both in vivo and in vitro, accompanied by an impairment in cardiac reserve and exercise capacity. Moreover, the cardiomyocytes lacking ZBTB20 showed an increase in sarcoplasmic reticular Ca2+ content and exhibited a remarkable enhancement in both SERCA2a activity and electrically stimulated contraction. Mechanistically, PLN expression was dramatically reduced in cardiomyocytes at the mRNA and protein levels by ZBTB20 deletion or silencing, and PLN overexpression could largely restore the basal contractility in ZBTB20-deficient cardiomyocytes. CONCLUSIONS: These data point to ZBTB20 as a fine-tuning modulator of PLN expression and SERCA2a activity, thereby offering new perspective on the regulation of basal contractility in the mammalian heart.
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Miocárdio , Retículo Sarcoplasmático , Animais , Camundongos , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Mamíferos , Camundongos Knockout , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismoRESUMO
Background and purpose: Acute kidney injury (AKI) is a common serious complication in sepsis patients with a high mortality rate. This study aimed to develop and validate a predictive model for sepsis associated acute kidney injury (SA-AKI). Methods: In our study, we retrospectively constructed a development cohort comprising 733 septic patients admitted to eight Grade-A tertiary hospitals in Shanghai from January 2021 to October 2022. Additionally, we established an external validation cohort consisting of 336 septic patients admitted to our hospital from January 2017 to December 2019. Risk predictors were selected by LASSO regression, and a corresponding nomogram was constructed. We evaluated the model's discrimination, precision and clinical benefit through receiver operating characteristic (ROC) curves, calibration plots, decision curve analysis (DCA) and clinical impact curves (CIC) in both internal and external validation. Results: AKI incidence was 53.2% in the development cohort and 48.2% in the external validation cohort. The model included five independent indicators: chronic kidney disease stages 1 to 3, blood urea nitrogen, procalcitonin, D-dimer and creatine kinase isoenzyme. The AUC of the model in the development and validation cohorts was 0.914 (95% CI, 0.894-0.934) and 0.923 (95% CI, 0.895-0.952), respectively. The calibration plot, DCA, and CIC demonstrated the model's favorable clinical applicability. Conclusion: We developed and validated a robust nomogram model, which might identify patients at risk of SA-AKI and promising for clinical applications.
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Injúria Renal Aguda , Sepse , Humanos , Nomogramas , Estudos Retrospectivos , ChinaRESUMO
Targeting PI3Kγ would be a useful strategy for treating inflammatory and cancer diseases. However, the development of selective inhibitors of PI3Kγ is very challenging due to the high structural and sequence homology with other PI3K isoforms. A series of quinazolinone derivatives were designed, synthesized and biologically evaluated as PI3Kγ-selective inhibitors. Among all the 28 compounds, compound 9b was found to be the most potent selective inhibitor with IC50 values of 13.11 nM against PI3Kγ kinase. Additionally, compound 9b could generate toxicity on leukemia cells in a panel of 12 different of cancer cell lines with the IC50 value of 2.41 ± 0.11 µM on Jurkat cell. Preliminary mechanism studies indicated that compound 9b through inhibit the activity of PI3K-AKT in human and murine leukemia cells, and activated phosphorylated p38 and phosphorylated ERK presented potent antiproliferative activity, which provided a potent small molecule for further cancer therapy.
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Antineoplásicos , Leucemia , Neoplasias , Inibidores de Proteínas Quinases , Quinazolinonas , Animais , Humanos , Camundongos , Antineoplásicos/química , Proliferação de Células , Desenho de Fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Quinazolinonas/química , Quinazolinonas/farmacologia , Relação Estrutura-Atividade , Classe Ib de Fosfatidilinositol 3-QuinaseRESUMO
RATIONALE: Impaired autophagic flux contributes to ischemia/reperfusion (I/R)-induced cardiomyocyte death, but the underlying molecular mechanisms remain largely unexplored. OBJECTIVE: To determine the role of LAPTM4B (lysosomal-associated transmembrane protein 4B) in the regulation of autophagic flux and myocardial I/R injury. METHODS AND RESULTS: LAPTM4B was expressed in murine hearts but downregulated in hearts with I/R (30 minutes/2 hours) injury and neonatal rat cardiomyocytes with hypoxia/reoxygenation (6 hours/2 hours) injury. During myocardial reperfusion, LAPTM4B-knockout (LAPTM4B-/-) mice had a significantly increased infarct size and lactate dehydrogenase release, whereas adenovirus-mediated LAPTM4B-overexpression was cardioprotective. Concomitantly, LAPTM4B-/- mice showed higher accumulation of the autophagy markers LC3-II (microtubule-associated protein 1A/1B-light chain 3), but not P62, in the I/R heart, whereas they did not alter chloroquine-induced further increases of LC3-II and P62 in both sham and I/R hearts. Conversely, LAPTM4B-overexpression had opposite effects. The hypoxia/reoxygenation-reduced viability of neonatal rat cardiomyocytes, ratio of autolysosomes/autophagosomes, and function of lysosomes were further decreased by LAPTM4B-knockdown but reversed by LAPTM4B-overexpression. Moreover, the LAPTM4B-overexpression-mediated benefits were abolished by knockdown of lysosome-associated membrane protein-2 (an autophagosome-lysosome fusion protein) in vivo and by the autophagy inhibitor bafilomycin A1 in vivo. In contrast, rapamycin (Rapa) successfully restored the impaired autophagic flux in LAPTM4B-/- mice and the subsequent myocardial I/R injury. Mechanistically, LAPTM4B regulated the activity of mTORC1 (mammalian target of rapamycin complex 1) via interacting with mTOR through its EC3 (extracelluar) domain. Thus, mTORC1 was overactivated in LAPTM4B-/- mice, leading to the repression of TFEB (transcription factor EB), a master regulator of lysosomal and autophagic genes, during myocardial I/R. The mTORC1 inhibition or TFEB-overexpression rescued the LAPTM4B-/--induced impairment in autophagic flux and I/R injury, whereas TFEB-knockdown abolished the LAPTM4B-overexpression-mediated recovery of autophagic flux and cardioprotection. CONCLUSIONS: The downregulation of LAPTM4B contributes to myocardial I/R-induced impairment of autophagic flux via modulation of the mTORC1/TFEB pathway. Graphic Abstract: A graphic abstract is available for this article.
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Autofagossomos/metabolismo , Autofagia , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Autofagossomos/genética , Autofagossomos/patologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Regulação para Baixo , Lisossomos/genética , Lisossomos/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/patologia , Ratos Sprague-Dawley , Proteína Sequestossoma-1/metabolismo , Transdução de SinaisRESUMO
Cardiac hypertrophy is a common adaptive response to a variety of stimuli, but prolonged hypertrophy leads to heart failure. Hence, discovery of agents treating cardiac hypertrophy is urgently needed. In the present study, we investigated the effects of QF84139, a newly synthesized pyrazine derivative, on cardiac hypertrophy and the underlying mechanisms. In neonatal rat cardiomyocytes (NRCMs), pretreatment with QF84139 (1-10 µM) concentration-dependently inhibited phenylephrine-induced hypertrophic responses characterized by fetal genes reactivation, increased ANP protein level and enlarged cardiomyocytes. In adult male mice, administration of QF84139 (5-90 mg·kg-1·d-1, i.p., for 2 weeks) dose-dependently reversed transverse aortic constriction (TAC)-induced cardiac hypertrophy displayed by cardiomyocyte size, left ventricular mass, heart weights, and reactivation of fetal genes. We further revealed that QF84139 selectively activated the AMPK signaling pathway without affecting the phosphorylation of CaMKIIδ, ERK1/2, AKT, PKCε, and P38 kinases in phenylephrine-treated NRCMs and in the hearts of TAC-treated mice. In NRCMs, QF84139 did not show additive effects with metformin on the AMPK activation, whereas the anti-hypertrophic effect of QF84139 was abolished by an AMPK inhibitor Compound C or knockdown of AMPKα2. In AMPKα2-deficient mice, the anti-hypertrophic effect of QF84139 was also vanished. These results demonstrate that QF84139 attenuates the PE- and TAC-induced cardiac hypertrophy via activating the AMPK signaling. This structurally novel compound would be a promising lead compound for developing effective agents for the treatment of cardiac hypertrophy.
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Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Cardiomegalia/patologia , Miócitos Cardíacos/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Aorta/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tamanho do Órgão/efeitos dos fármacos , Fenilefrina/farmacologia , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: The incidence of Candida bloodstream infections (BSIs), has increased over time. In this study, we aimed to describe the current epidemiology of Candida BSI in a large tertiary care hospital in Shanghai and to determine the risk factors of 28-day mortality and the impact of antifungal therapy on clinical outcomes. METHODS: All consecutive adult inpatients with Candida BSI at Ruijin Hospital between January 1, 2008, and December 31, 2018, were enrolled. Underlying diseases, clinical severity, species distribution, antifungal therapy, and their impact on the outcomes were analyzed. RESULTS: Among the 370 inpatients with 393 consecutive episodes of Candida BSI, the incidence of nosocomial Candida BSI was 0.39 episodes/1000 hospitalized patients. Of the 393 cases, 299 (76.1%) were treated with antifungal therapy (247 and 52 were treated with early appropriate and targeted antifungal therapy, respectively). The overall 28-day mortality rate was 28.5%, which was significantly lower in those who received early appropriate (25.5%) or targeted (23.1%) antifungal therapy than in those who did not (39.4%; P = 0.012 and P = 0.046, respectively). In multivariate Cox regression analysis, age, chronic renal failure, mechanical ventilation, and severe neutropenia were found to be independent risk factors of the 28-day mortality rate. Patients who received antifungal therapy had a lower mortality risk than did those who did not. CONCLUSIONS: The incidence of Candida BSI has increased steadily in the past 11 years at our tertiary care hospital in Shanghai. Antifungal therapy influenced short-term survival, but no significant difference in mortality was observed between patients who received early appropriate and targeted antifungal therapy.
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Antifúngicos/uso terapêutico , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Sepse/epidemiologia , Sepse/microbiologia , Adulto , Idoso , Candidíase/epidemiologia , Candidíase/microbiologia , Candidíase/mortalidade , China/epidemiologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/mortalidade , Feminino , Humanos , Incidência , Pacientes Internados , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Sepse/tratamento farmacológico , Sepse/mortalidade , Centros de Atenção Terciária , Resultado do TratamentoRESUMO
BACKGROUND: Polycystic ovary syndrome (PCOS) is one of the most common endocrine metabolic disorders characterized by hyperandrogenism, polycystic ovaries and ovulatory dysfunction. Several studies have reported that the aberrant expression of miRNAs contributes a lot to disordered folliculogenesis in PCOS, though the role and underlying mechanism of microRNA-200b (miR-200b) and microRNA-200c (miR-200c) in the development of PCOS remain unclear. METHODS: The expression of miR-200b in granulosa cells (GCs) derived from 90 PCOS patients and 70 controls was analyzed by using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Granulosa-like tumor cell line (KGN) was cultured for cell counting kit-8 (CCK-8) assays after over-expression of miR-200b, miR-200c or knockdown phosphatase and tensin homolog (PTEN). TargetScan was used to identify the potential targets of miR-200b and miR-200c, which was further verified by qRT-PCR, western blot and luciferase assays. RESULTS: Significantly increased expression of miR-200b was observed in PCOS patients compared with the controls. Moreover, over-expression of miR-200b and miR-200c inhibited the proliferation of KGN cells. In addition, our results verified that miR-200b and miR-200c directly targeted PTEN, knockdown of which suppressed KGN cells proliferation. CONCLUSION: Our findings demonstrate that miR-200b and miR-200c suppress the proliferation of KGN cells by targeting PTEN, and this might provide new evidence for abnormal proliferation of GCs in PCOS.
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Proliferação de Células/genética , Células da Granulosa/metabolismo , MicroRNAs/genética , PTEN Fosfo-Hidrolase/genética , Síndrome do Ovário Policístico/genética , Regulação para Cima , Adulto , Linhagem Celular Tumoral , Feminino , Células da Granulosa/patologia , Humanos , PTEN Fosfo-Hidrolase/metabolismo , Síndrome do Ovário Policístico/diagnóstico , Síndrome do Ovário Policístico/metabolismo , Interferência de RNA , Transdução de Sinais/genéticaRESUMO
Vasculogenic mimicry (VM) refers to the unique capability of aggressive tumor cells to mimic the pattern of embryonic vasculogenic networks. Cancer stem cells (CSC) represent a subpopulation of tumor cells endowed with the capacity for self-renewal and multilineage differentiation. Previous studies have indicated that CSC may participate in the formation of VM. With the advance of high-resolution microarrays and massively parallel sequencing technology, long noncoding RNAs (lncRNAs) are suggested to play a critical role in tumorigenesis and, in particular, the development of human hepatocellular carcinoma (HCC). Currently, no definitive relationship between lncRNA and VM formation has been described. In the current study, we demonstrated that expression of the lncRNA, n339260, is associated with CSC phenotype in HCC, and n339260 level correlated with VM, metastasis, and shorter survival time in an animal model. Overexpression of n339260 in HepG2 cells was associated with a significant increase in CSC. Additionally, the appearance of VM and vascular endothelial (VE)-cadherin, a molecular marker of VM, was also induced by n339260 overexpression. Using a short hairpin RNA approach, n339260 was silenced in tumor cells, and knockdown of n339260 was associated with reduced VM and CSC. The results of this study indicate that n339260 promotes VM, possibly by the development of CSC. The related molecular pathways may be used as novel therapeutic targets for the inhibition of HCC angiogenesis and metastasis.
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Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica/genética , RNA Longo não Codificante/metabolismo , Animais , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Diferenciação Celular/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células Hep G2 , Hepatectomia , Humanos , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Patológica/mortalidade , Neovascularização Patológica/patologia , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Esferoides Celulares , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Chinese population are experiencing remarkably changes of economic and cultural environments. The present study was to examine the prevalence of metabolic syndrome (MetS) by age between genders and to investigate the current characteristics of MetS and its components in China. METHODS: SPECT-China is a population-based cross-sectional survey on Chinese adults aged ≥18 years in East China. A total of 10,441 Chinese residents participated in anthropometric and laboratory measurements. Of these, 9969 subjects (females, 5868) were eligible for the data analysis reported here. Estimates of the prevalence of MetS and its components were calculated. Presence of MetS was defined based on the IDF/AHA harmonized criteria. MetS z-score was calculated to evaluate the degree of total metabolic disorder. RESULTS: The age-standardized prevalence of the metabolic syndrome was 22.0% (21.9% in men and 22.0% in women). Unlike the continuous MetS rise with age in females, the MetS prevalence in males remained stable among 46-55, 56-65 and > 65 yrs. age groups (31.2%, 31.4%, 32.5%, p = 0.538). In the five components of MetS, contrary to the elevated BP and BG disorders, the frequency of TG disorders decreased with age in males (46.6%(46-55 yrs), 37.2% (56-65 yrs), 27.7%(> 65 yrs), p < 0.001). Multivariable logistic regression showed that in males, more TG disorders were associated with higher BMI, higher educational level and current nonsmoker. In the MetS subjects, the 3-factor combinations which included TG disorders decreased with age in both genders. The whole metabolic profile became better in older male MetS subjects, which was opposite to the female. CONCLUSION: Our results showed a distinct age-related prevalence of MetS between genders in dramatically changed China, in which the TG disorders played an important role. More targeted measures need to be taken to meet the serious challenges of metabolic diseases. TRIAL REGISTRATION: ChiCTR-ECS- 14005052 , Survey on Prevalence in East China for Metabolic Diseases and Risk Factors (SPECT-China).
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Hipertrigliceridemia/epidemiologia , Síndrome Metabólica/epidemiologia , Triglicerídeos/sangue , Adulto , Idoso , Antropometria , Glicemia/metabolismo , Pressão Sanguínea , Índice de Massa Corporal , China/epidemiologia , HDL-Colesterol/sangue , Estudos Transversais , Feminino , Humanos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/fisiopatologia , Modelos Logísticos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Sexuais , Circunferência da CinturaRESUMO
OBJECTIVE: Vitamin D is a multifunctional vitamin for our body. Type 2 diabetes mellitus (T2DM) is a common metabolic disease. Whether T2DM affects the serum 25(OH)D level has not been reported. The objective of this study was to reveal the extent to which vitamin D is present in the population in East China and to explore the relationship between serum 25(OH)D and T2DM. METHODS: The cohort was selected based on a large investigation named Survey on Prevalence in East China including 12,702 participants aged 21-92 years old. All the participants completed the questionnaire and went through a physical examination. Fasting blood samples were collected to test serum 25(OH)D and other metabolism-related indicators. AVONA was used to test the significance of differences among groups. Multinomial logistic regression was used to assess the association of T2DM with serum 25(OH)D level. RESULTS: The overall percentage of vitamin D deficiency was 80.55% (male 74.1%, female 85.0%). Men with lower serum 25(OH)D level had high value in homeostasis model assessment of insulin resistance and HbA1c. The serum 25(OH)D level of those who were diagnosed with T2DM was higher than that in non-diabetics. The serum 25(OH)D level of pre-diabetes was the highest. T2DM patients trended to have higher serum 25(OH)D levels. CONCLUSION: Vitamin D deficiency is common among the people in East-China. T2DM patients had higher levels of serum 25(OH)D. The relationship between vitamin D and T2DM is intriguing. It seemed that vitamin D was either irrelevant directly to T2DM or resisted in T2DM patients.
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Diabetes Mellitus Tipo 2/epidemiologia , Deficiência de Vitamina D/epidemiologia , Vitamina D/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia , China/epidemiologia , Feminino , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
To characterize the contributions of Dickkopf-1 (DKK1) towards the induction of vasculogenic mimicry (VM) in non-small cell lung cancer (NSCLC), we evaluated cohorts of primary tumours, performed in vitro functional studies and generated xenograft mouse models. Vasculogenic mimicry was observed in 28 of 205 NSCLC tumours, while DKK1 was detected in 133 cases. Notably, DKK1 was positively associated with VM. Statistical analysis showed that VM and DKK1 were both related to aggressive clinical course and thus were indicators of a poor prognosis. Moreover, expression of epithelial-mesenchymal transition (EMT)-related proteins (vimentin, Slug, and Twist), cancer stem-like cell (CSC)-related proteins (nestin and CD44), VM-related proteins (MMP2, MMP9, and vascular endothelial-cadherin), and ß-catenin-nu were all elevated in VM-positive and DKK1-positive tumours, whereas the epithelial marker (E-cadherin) was reduced in the VM-positive and DKK1-positive groups. Non-small cell lung cancer cell lines with overexpressed or silenced DKK1 highlighted its role in the restoration of mesenchymal phenotypes and development of CSC characteristics. Moreover, DKK1 significantly promotes NSCLC tumour cells to migrate, invade and proliferate. In vivo animal studies demonstrated that DKK1 enhances the growth of transplanted human tumours cells, as well as increased VM formation, mesenthymal phenotypes and CSC properties. Our results suggest that DKK1 can promote VM formation via induction of the expression of EMT and CSC-related proteins. As such, we feel that DKK1 may represent a novel target of NSCLC therapy.
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Carcinoma Pulmonar de Células não Pequenas/irrigação sanguínea , Carcinoma Pulmonar de Células não Pequenas/patologia , Transição Epitelial-Mesenquimal , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/patologia , Mimetismo Molecular , Células-Tronco Neoplásicas/patologia , Animais , Vasos Sanguíneos/patologia , Movimento Celular , Proliferação de Células , Forma Celular , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fenótipo , RNA Interferente Pequeno/metabolismo , Transfecção , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The growth mechanism of an octadecyltrichlorosilane (OTS) self-assembled monolayer on a silicon oxide surface at various relative humidities has been investigated. Atomic force microscopy images show that excess water may actually hinder the nucleation and growth of OTS islands. A moderate amount of water is favorable for the nucleation and growth of OTS islands in the initial stage; however, the completion of the monolayer is very slow in the final stage. The growth of OTS islands on a low-water-content surface maintains a relatively constant speed and requires the least amount of time. The mobility of water molecules is thought to play an important role in the OTS monolayers, and a low-mobility water layer provides a steady condition for OTS monolayer growth.
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Although ischemia/reperfusion (I/R)-induced myocardial contractile dysfunction is associated with a prominent decrease in myofilament Ca(2+) sensitivity, the underlying mechanisms have not yet been fully clarified. Phosphorylation of ventricular myosin light chain 2 (MLC-2v) facilitates actin-myosin interactions and enhances contractility, however, its level and regulation by cardiac MLC kinase (cMLCK) and cMLC phosphatase (cMLCP) in I/R hearts are debatable. In this study, the levels and/or effects of MLC-2v phosphorylation, cMLCK, cMLCP, and proteases during I/R were determined. Global myocardial I/R-suppressed cardiac performance in isolated rat hearts was concomitant with decreases of MLC-2v phosphorylation, myofibrillar Ca(2+)-stimulated ATPase activity, and cMLCK content, but not cMLCP proteins. Consistently, simulated I/R in isolated cardiomyocytes inhibited cell shortening, Ca(2+) transients, MLC-2v phosphorylation, and myofilament sensitivity to Ca(2+). These observations were reversed by cMLCK overexpression, while the specific cMLCK knockdown by short hairpin RNA (shRNA) had the opposite effect. Moreover, the inhibition of matrix metalloproteinase-2 (MMP-2, a zinc-dependent endopeptidase) reversed IR-decreased cMLCK, MLC-2v phosphorylation, myofibrillar Ca(2+)-stimulated ATPase activity, myocardial contractile function, and myofilament sensitivity to Ca(2+), while the inhibition or knockdown of cMLCK by ML-9 or specific shRNA abolished MMP-2 inhibition-induced cardioprotection. Finally, the co-localization in cardiomyocytes and interaction in vivo of MMP-2 and cMLCK were observed. Purified recombinant rat cMLCK was concentration- and time-dependently degraded by rat MMP-2 in vitro, and this was prevented by the inhibition of MMP-2. These findings reveal that the I/R-activated MMP-2 leads to the degradation of cMLCK, resulting in a reduction of MLC-2v phosphorylation, and myofibrillar Ca(2+)-stimulated ATPase activity, which subsequently suppresses myocardial contractile function through a decrease of myofilament Ca(2+) sensitivity.
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Metaloproteinase 2 da Matriz/metabolismo , Traumatismo por Reperfusão Miocárdica/enzimologia , Quinase de Cadeia Leve de Miosina/metabolismo , Animais , Células Cultivadas , Masculino , Contração Miocárdica , Isquemia Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/enzimologia , Miocárdio/patologia , Miócitos Cardíacos/enzimologia , Processamento de Proteína Pós-Traducional , Proteólise , Ratos Sprague-DawleyRESUMO
The anionic Zn-2,5-thiophenedicarboxylate framework material (1) built from the connection of Johnson cages can perform Ag(+)-exchange to upgrade the uptakes of C2 hydrocarbons (C2s) and separation properties of C2s over methane (C1). Moreover, its activated phase (1a) can enrich organic dyes from ethanol and make a significant red-shift in photoluminescent spectra of Rhodamine B (Rh B) via varying the aggregation states of dye molecules.
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Early-onset prostate cancer (EOPC) is relatively uncommon. It is unclear if the incidence of EOPC is evolving. Utilizing data from the SEER database from 2000 to 2020, the study identified prostate cancer cases in men under 55 years, focusing on trends in annual age-adjusted incidence rates (AAIR), stage at presentation, race/ethnicity, and local treatment patterns. The study encompassed 93â 071 cases of EOPC, with the median age at diagnosis being 51 years. From 2000 to 2007, the AAIR of EOPC experienced a wave-like increase from 6.9 to 8.3 per 100â 000 people. It then sharply declined to 5.4 by 2014, followed by 6 years of stability, and by 2020 it had dropped to its lowest point of 4.5. The trend observed across different racial groups was consistent with the overall pattern, where non-Hispanic Black patients consistently exhibited the highest incidence and the least reduction rate (annual percent change, -1.0; 95% confidence interval, -1.8 to -0.2; Pâ <â 0.05). Stage II was the most commonly diagnosed, although its AAIR declined from 4.9 to 1.2 per 100â 000 people. From 2010 through 2020, the proportion of receiving prostatectomy decreased from 63.0 to 43.6%. The declining rates of EOPC across diverse racial groups emphasize the critical need for focused research and interventions. Specifically, there is an urgent call to establish a tailored screening protocol for prostate cancer targeting Black youth.
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Background: In addition to excessive inflammation, immunosuppression has been recognized as a contributing factor to poor prognosis of sepsis. Although it has been reported that T cells can become functionally impaired during sepsis, the underlying mechanisms responsible for this phenomenon remain unclear. This study aims to elucidate the mechanisms by which macrophages induce immunosuppression in T cells. Methods: In an in vivo setting, C57BL-6J mice were subjected to cecal ligation and puncture (CLP) with or without depletion of macrophages, and the functions of T cells were assessed. In vitro experiments involved direct co-culture or separate culture of T cells and septic macrophages using a transwell system, followed by analysis of T cell immunity. Additionally, a siRNA targeting CD18 on macrophages was utilized to investigate the role of complement receptor 3 (CR3). Results: Both macrophages and T cells exhibited immunosuppression during sepsis. In the in vivo experiments, the absence of macrophages partially alleviated T cell immunosuppression, as evidenced by restored vitality, increased production of TNF-α and IFN-γ, elevated CD8+ T cell levels, and decreased CD25+ T cell levels. In the in vitro experiments, direct co-culture of T cells with septic macrophages resulted in diminished T cell immunity, which was improved when T cells and macrophages were separated by a chamber wall. The expression of CR3 (CD11b/CD18) was upregulated on septic macrophages, and silencing of CD18 led to decreased TNF-α production by T cells, reduced CD4+ T cell numbers, and increased CD25+ T cell numbers. Conclusion: In sepsis, macrophages induce immunosuppression in T cells through direct cell-cell contact, with the involvement of CR3.
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OBJECTIVE: Poststroke cognitive impairment substantially affects patients' quality of life. This study explored the therapeutic efficacy of intermittent theta burst stimulation combined with cognitive training for poststroke cognitive impairment. DESIGN: The experimental group received intermittent theta burst stimulation and cognitive training, whereas the control group only received cognitive training, both for 6 wks. The outcome measures were the Loewenstein Occupational Therapy Cognitive Assessment, modified Barthel Index, transcranial Doppler ultrasonography, and functional near-infrared spectroscopy. RESULTS: After therapy, between-group comparisons revealed a substantial difference in the Loewenstein Occupational Therapy Cognitive Assessment scores ( P = 0.024). Improvements in visuomotor organization and thinking operations were more noticeable in the experimental group than in the other groups ( P = 0.017 and P = 0.044, respectively). After treatment, the resistance index of the experimental group differed from that of the control group; channels 29, 37, and 41 were activated ( P < 0.05). The active locations were the left dorsolateral prefrontal cortex, prefrontal polar cortex, and left Broca's region. CONCLUSIONS: Intermittent theta burst stimulation combined with cognitive training had a superior effect on improving cognitive function and everyday activities compared with cognitive training alone, notably in visuomotor organization and thinking operations. Intermittent theta burst stimulation may enhance cognitive performance by improving network connectivity.
Assuntos
Disfunção Cognitiva , Estimulação Magnética Transcraniana , Humanos , Estimulação Magnética Transcraniana/métodos , Método Simples-Cego , Treino Cognitivo , Qualidade de Vida , Ritmo Teta/fisiologia , Córtex Pré-Frontal , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapiaRESUMO
Cholesterol is an important lipid playing a crucial role in mediating essential cellular processes as well as maintaining the basic structural integrity of biological membranes. Given its vast biological importance, there is an unabated need for sophisticated strategies to investigate cholesterol-mediated biological processes. Raman-tagged sterol analogs offer the advantage of being visualizable without the need for a bulky dye that potentially affects natural membrane integration and cellular interactions as it is the case for many conventionally used fluorescent analogs. Herein, we report a series of alkyne-tagged imidazolium-based cholesterol analogs (CHIMs) with large Raman scattering cross-sections that readily integrate into HEK cells and primary monocyte-derived macrophages and allow (multiplexed) cellular Raman imaging. We envision Raman-tagged CHIM analogs to be a powerful platform for the investigation of cholesterol-mediated cellular processes complementary to other established methods, such as the use of fluorescent analogs.
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Exploring the alterations in functional traits of urban remnant vegetation offers a more comprehensive perspective on plant assembly within the context of urbanization. While plant functional traits are influenced by both environmental gradients and the evolutionary history of plant species, the specific mechanisms by which urbanization mediates the combination of functional traits and the evolutionary history of remnant vegetation remain unclear. To examine the relationship between functional traits and phylogenies of remnant vegetation and urbanization, we classified the woody plant species surveyed in 72 sample plots in nine remnant forest patches in Guiyang, China, into four groups (urban, rural, middle and general groups) according to their location under different levels of urbanization and measured nine functional traits of these species. The phylogenetic signals of each functional trait of the four species groups were then quantified based on Blomberg's K. Furthermore, we analysed the correlations between functional traits and species abundance using phylogenetic generalized least squares. The results showed that significant phylogenetic signals were detected in more functional traits of the urban group than other groups. Thirteen and three significant relationships between functional traits and species abundance were detected for tree and shrub species after removing phylogenies. Tall tree species were more abundant in the urban group, while the general group favoured the species with adaptable traits (low height and high leaf area and C/N). Overall, we demonstrate that urbanization drove shifts in plant functional traits in remnant forests after combining the phylogenetic patterns.
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The nongenetic modification of cell membranes with proteins is a straightforward way of cellular engineering. In these processes, it is important to specifically address the proteins to liquid-ordered (Lo) or liquid-disordered (Ld) domains as this can largely affect their biological functions. Herein, we report a cholesterol analogue (CHIM) with a nitrilotriacetic acid (NTA) headgroup, named CHIM-NTA. CHIM-NTA integrates into lipid membranes similar to the widely used phospholipid-derived DGS-NTA and, when loaded with Ni2+, allows for specific membrane immobilization of any polyhistidine-tagged proteins of choice. Yet, unlike DGS-NTA, it localizes to the Lo phase in phase-separated giant unilamellar vesicles (GUVs) and allows addressing His-tagged proteins to Lo domains. Furthermore, CHIM-NTA readily integrates into the membranes of live cells and thus enables the nongenetic modification of the cell surface with proteins. Overall, CHIM-NTA provides a facile and flexible way to modify biological membranes, in particular Lo domains, with His-tagged proteins and can serve as a broadly applicable molecular tool for cell surface engineering.