Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 58
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
BMC Psychiatry ; 24(1): 281, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622613

RESUMO

BACKGROUND: Violence in schizophrenia (SCZ) is a phenomenon associated with neurobiological factors. However, the neural mechanisms of violence in patients with SCZ are not yet sufficiently understood. Thus, this study aimed to explore the structural changes associated with the high risk of violence and its association with impulsiveness in patients with SCZ to reveal the possible neurobiological basis. METHOD: The voxel-based morphometry approach and whole-brain analyses were used to measure the alteration of gray matter volume (GMV) for 45 schizophrenia patients with violence (VSC), 45 schizophrenia patients without violence (NSC), and 53 healthy controls (HC). Correlation analyses were used to examine the association of impulsiveness and brain regions associated with violence. RESULTS: The results demonstrated reduced GMV in the right insula within the VSC group compared with the NSC group, and decreased GMV in the right temporal pole and left orbital part of superior frontal gyrus only in the VSC group compared to the HC group. Spearman correlation analyses further revealed a positive correlation between impulsiveness and GMV of the left superior temporal gyrus, bilateral insula and left medial orbital part of the superior frontal gyrus in the VSC group. CONCLUSION: Our findings have provided further evidence for structural alterations in patients with SCZ who had engaged in severe violence, as well as the relationship between the specific brain alterations and impulsiveness. This work provides neural biomarkers and improves our insight into the neural underpinnings of violence in patients with SCZ.


Assuntos
Esquizofrenia , Humanos , Masculino , Esquizofrenia/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Córtex Pré-Frontal , Córtex Cerebral/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
2.
Asia Pac J Clin Nutr ; 33(3): 370-380, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38965724

RESUMO

BACKGROUND AND OBJECTIVES: Patients with inflammatory bowel disease (IBD) are more likely to be confirmed with vitamin D deficiency. However, the association between inflammation and vitamin D remains unclear. The purpose of this study was to evaluate the association between inflammation and vitamin D in hospitalized patients with IBD. METHODS AND STUDY DESIGN: All the participants were recruited from one teaching hospital from June 2018 to October 2022. Inflammation was evaluated by serum concentration of C-reactive protein (CRP), using an immunoturbidimetric method at admission. We further divided the participants into five groups based on serum CRP levels: <5, 5-9.9, 10-19.9, 20-39.9, and >40mg/L. Serum 25-hydroxy-vitamin D (25-(OH)-D) was assessed by liquid chromatography tandem mass spectrometry. Addi-tional information, including age, sex, body mass index (BMI), IBD (ulcerative colitis vs. Crohn's disease) subtype, was abstracted from medical records. RESULTS: This study included 1,989 patients with IBD (average age was 39.4 years, 33.8% of them were women, 1,365 CD and 624 UC patients). The median CRP was 5.49 mg/L (range of quartiles: 1.64~19.5 mg/L) and the prevalence of 25-(OH)-D deficiency was 69.8%. CRP was significantly associated with serum level of 25-(OH)-D. The difference in 25-(OH)-D was -4.28 ng/ml (-5.27 ng/ml, -3.31 ng/ml) between two extremist CRP groups after adjustment of potential covariates (age, sex, BMI, type of IBD, dietary type, season, and lymphocyte count). Subgroup analysis in sex, type of IBD, and age, were similar to the main analysis results. CONCLUSIONS: There was a negative association between CRP levels and vitamin D in hospitalized patients with IBD.


Assuntos
Proteína C-Reativa , Hospitalização , Doenças Inflamatórias Intestinais , Deficiência de Vitamina D , Vitamina D , Humanos , Feminino , Masculino , Vitamina D/sangue , Vitamina D/análogos & derivados , China/epidemiologia , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/epidemiologia , Proteína C-Reativa/análise , Adulto , Pessoa de Meia-Idade , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações , Adulto Jovem
3.
Angew Chem Int Ed Engl ; 63(24): e202318389, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38613385

RESUMO

Being an efficient approach to the utilization of hydrogen energy, the hydrogen oxidation reaction (HOR) is of particular significance in the current carbon-neutrality time. Yet the mechanistic picture of the HOR is still blurred, mostly because the elemental steps of this reaction are rapid and highly entangled, especially when deviating from the thermodynamic equilibrium state. Here we report a strategy for decoding the HOR mechanism under operando conditions. In addition to the wide-potential-range I-V curves obtained using gas diffusion electrodes, we have applied the AC impedance spectroscopy to provide independent and complementary kinetic information. Combining multidimensional data sources has enabled us to fit, in mathematical rigor, the core kinetic parameter set in a 5-D data space. The reaction rate of the three elemental steps (Tafel, Heyrovsky, and Volmer reactions), as a function of the overpotential, can thus be distilled individually. Such an undocumented kinetic picture unravels, in detail, how the HOR is controlled by the elemental steps on polarization. For instance, at low polarization region, the Heyrovsky reaction is relatively slow and can be ignored; but at high polarization region, the Heyrovsky reaction will surpass the Tafel reaction. Additionally, the Volmer reaction has been the fastest within overpotentials of interest. Our findings not only offer a better understanding of the HOR mechanism, but also lay the foundation for the development of improved hydrogen energy utilization systems.

4.
Dig Dis Sci ; 68(4): 1316-1331, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36002674

RESUMO

BACKGROUND: TOB1, a member of the transducer of erbB-2 /B-cell translocation gene family, was detected to be down-regulated in ESCC by RNA sequencing. TOB1-AS1, a head-to-head antisense lncRNA with TOB1, was down-regulated in several cancers. However, the roles of them in esophageal squamous cell carcinoma (ESCC) remained unclarified. AIMS: To investigate the roles and functions of TOB1-AS1 and TOB1 in ESCC tumorigenesis. MATERIALS AND METHODS: The expression levels, methylation status, biological function and mechanisms of TOB1-AS1 and TOB1 in ESCC were, respectively, detected. RESULTS: Frequent down-regulation of TOB1-AS1 and TOB1 was verified in esophageal cancer cells and ESCC tissues, and there was a positive correlation between them in ESCC tissues. The CpG sites hypermethylation within proximal promoter of TOB1-AS1 and TOB1 could lead to transcriptional inhibition of both genes. Furthermore, expression and proximal promoter methylation status of TOB1-AS1 or TOB1 may be associated with ESCC patients' prognosis. TOB1-AS1 and TOB1 may function as tumor suppressors by inhibiting growth, migration, and invasion of esophageal cancer cells. Up-regulation of TOB1-AS1 increased expression level of TOB1, and TOB1-AS1 could work as a ceRNA to modulate ATF3 expression via competitively binding with miR-103a-2-5p. Meanwhile, ATF3, as a transcription factor, could regulate transcription of TOB1; down-regulation of TOB1-AS1 in ESCC led to decreased expression of ATF3 through ceRNA mechanism, and further influenced the transcription of TOB1. CONCLUSION: TOB1-AS1 and TOB1 may act as tumor suppressors and may serve as potential targets for antitumor therapy in ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , RNA Longo não Codificante , Humanos , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação para Baixo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Progressão da Doença , Linhagem Celular Tumoral , Prognóstico , Metilação de DNA , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
5.
BMC Gastroenterol ; 22(1): 163, 2022 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-35369868

RESUMO

BACKGROUND: Estimates of cervical lymph node (LN) metastasis in patients with middle and lower thoracic esophageal squamous cell carcinoma (ESCC) are important. A nomogram is a useful tool for individualized prediction. METHODS: A total of 235 patients were enrolled in this study. Univariate and multivariate analyses were performed to screen for independent risk factors and construct a nomogram to predict the risk of cervical LN metastasis. The nomogram performance was assessed by discrimination, calibration, and clinical use. RESULTS: Totally, four independent predictors, including the maximum diameter of tumor, paraesophageal lymph node status, recurrent laryngeal nerve lymph node status, and the CT-reported cervical LN status, were enrolled in the nomogram. The AUC of the nomogram model in the training and validation dataset were 0.833 (95% CI 0.762-0.905), 0.808 (95% CI 0.696-0.920), respectively. The calibration curve demonstrated a strong consistency between nomogram and clinical findings in predicting cervical LN metastasis. Decision curve analysis demonstrated that the nomogram was clinically useful. CONCLUSION: We developed a nomogram that could be conveniently used to predict the individualized risk of cervical LN metastasis in patients with middle and lower thoracic ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Humanos , Linfonodos/patologia , Metástase Linfática/patologia , Nomogramas , Tomografia Computadorizada por Raios X
6.
Mol Carcinog ; 60(12): 859-873, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34551139

RESUMO

The transcription factor forkhead box D3 (FOXD3) is an important member of the FOX family, which can maintain the pluripotent properties of cell clusters, neural crest, and trophoblastic progenitor cells in vivo. It has been shown that FOXD3 could affect proliferation, migration, and angiogenesis of various tumors and its deletion and overexpression in organisms will undoubtedly have important influence on the change of cell fate and the occurrence of tumors. However, the underlying functions and molecular mechanisms of FOXD3 in esophageal squamous cell carcinoma (ESCC) have not been fully clarified. According to the present study, the expression levels and functional roles of FOXD3 were investigated, and its prognostic value and molecular mechanisms in tumorigenesis and progression of ESCC were clarified. The expression level of FOXD3 was significantly downregulated in ESCC tissues and cell lines, and correlated with gender, family history of upper gastrointestinal cancer, TNM stage, depth of invasion, lymph node metastasis, and ESCC patients' survival. Moreover, FOXD3 inhibited cells migration and invasion as well as participated in TGF-ß1 induced epithelial-mesenchymal transition process. Furthermore, a positive correlation between FOXD3 and SMAD family member 7 (SMAD7) was explored in ESCC. FOXD3 could directly bind to promoter regions of SMAD7 gene, leading to transcriptional promotion of SMAD7 in human esophageal cancer cells. Taken together, FOXD3 may play a tumor suppressor role in ESCC and may be applied as a new therapeutic target and prognostic marker for ESCC.


Assuntos
Regulação para Baixo , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Fatores de Transcrição Forkhead/metabolismo , Proteína Smad7/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Transição Epitelial-Mesenquimal , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Prognóstico , Regiões Promotoras Genéticas
7.
FASEB J ; 33(5): 6564-6573, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30807702

RESUMO

FOXF2 and FOXQ1, forkhead box transcription factor superfamily members, are encoded by neighboring genes located on human chromosome 6p25.3 and play opposite roles in epithelial-mesenchymal transition (EMT) and metastasis in basal-like breast cancer (BLBC). However, the relationship between FOXF2 and FOXQ1 in cancer remains unknown. Here, we found mutual transcriptional repression between FOXF2 and FOXQ1, and the reciprocal negative feedback loop controlled EMT, aggressiveness, and chemoresistance in BLBC cells. We further demonstrated that FOXF2 recruited nuclear receptor corepressor 1 and histone deacetylase 3 to the FOXQ1 promoter to inhibit its transcription in BLBC cells, but FOXQ1 did not exert such an effect on FOXF2. Our findings reveal novel mechanisms underlying the determination of BLBC aggressiveness and the transrepressive function of FOXF2 in a basal-like cell subtype-specific manner. Therefore, blocking the vicious cycle of the abnormal reciprocal feedback loop between FOXF2 and FOXQ1 to induce cell differentiation and restore tissue homeostasis is a promising strategy for the treatment of aggressive BLBC.-Kang, L.-J., Yu, Z.-H., Cai, J., He, R., Lu, J.-T., Hou, C., Wang, Q.-S., Li, X.-Q., Zhang, R., Feng, Y.-M. Reciprocal transrepression between FOXF2 and FOXQ1 controls basal-like breast cancer aggressiveness.


Assuntos
Neoplasias da Mama/metabolismo , Transição Epitelial-Mesenquimal , Fatores de Transcrição Forkhead/biossíntese , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Fatores de Transcrição Forkhead/genética , Humanos , Células MCF-7 , Proteínas de Neoplasias/genética
8.
Langmuir ; 35(42): 13607-13613, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31554400

RESUMO

The self-healing feature of gallium (Ga) is unique, making Ga-based materials attract attention for their potential to solve the anode pulverization issue of lithium ion batteries. In this work, a hierarchical two-dimensional (2D) Ga2O3/C structure has been synthesized by a facile NaCl template method. Ga2O3 nanoparticles (3.8 nm) are uniformly embedded in 2D carbon nanosheets. The long horizontal length of the carbon nanosheets (10 µm) provides long-range electron conductivity, and the thin vertical thickness (75 nm) shortens the Li ion diffusion path. Benefited from the integrated 2D structure and the high electron conductivity, the obtained 2D Ga2O3/C nanosheets exhibit excellent overall performance, including high lithium storage capacity (1026 mAh g-1 at 0.5 A g-1), high rate capability (378 mAh g-1 at 10.0 A g-1), and high cyclability (500 cycles at 0.5 A g-1). The lithiation/delithiation mechanism of 2D Ga2O3/C has been further studied with combined electrochemical and ex situ X-ray diffraction methods.

9.
Angew Chem Int Ed Engl ; 58(5): 1442-1446, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30548378

RESUMO

The Pt-catalyzed hydrogen oxidation reaction (HOR) for alkaline polymer electrolyte fuel cells (APEFCs) has been one of the focus subjects in current fuel-cell research. The Pt catalyst is inferior for HOR in alkaline solutions, and alloying with Ru is an effective promotion strategy. APEFCs with Pt-Ru anodes have provided a performance benchmark over 1 W cm-2 at 60 °C. The Pt anode is now found to be in fact as good as the Pt-Ru anode for APEFCs operated at elevated conditions. At 80 °C with appropriate gas back-pressure, the cell with a Pt anode exhibits a peak power density of about 1.9 W cm-2 , which is very close to that with a Pt-Ru anode. Even by decreasing the anode Pt loading to 0.1 mg cm-2 , over 1.5 W cm-2 can still be achieved at 80 °C. This finding alters the previous understanding about the Pt catalyzed HOR in alkaline media and casts a new light on the development of practical and high-power APFEC technology.

10.
Angew Chem Int Ed Engl ; 55(21): 6239-43, 2016 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-27072349

RESUMO

A new property is reported that accurately quantifies and spatially describes the chemical reactivity of solid surfaces. The core idea is to create a reactivity weight function peaking at the Fermi level, thereby determining a weighted summation of the density of states of a solid surface. When such a weight function is defined as the derivative of the Fermi-Dirac distribution function at a certain non-zero temperature, the resulting property is the finite-temperature chemical softness, termed Fermi softness (SF ), which turns out to be an accurate descriptor of the surface reactivity. The spatial image of SF maps the reactive domain of a heterogeneous surface and even portrays morphological details of the reactive sites. SF analyses reveal that the reactive zones on a Pt3 Y(111) surface are the platinum sites rather than the seemingly active yttrium sites, and the reactivity of the S-dimer edge of MoS2 is spatially anisotropic. Our finding is of fundamental and technological significance to heterogeneous catalysis and industrial processes demanding rational design of solid catalysts.

11.
J Am Chem Soc ; 136(27): 9643-9, 2014 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-24936859

RESUMO

The dependence on Pt catalysts has been a major issue of proton-exchange membrane (PEM) fuel cells. Strategies to maximize the Pt utilization in catalysts include two main approaches: to put Pt atoms only at the catalyst surface and to further enhance the surface-specific catalytic activity (SA) of Pt. Thus far there has been no practical design that combines these two features into one single catalyst. Here we report a combined computational and experimental study on the design and implementation of Pt-skin catalysts with significantly improved SA toward the oxygen reduction reaction (ORR). Through screening, using density functional theory (DFT) calculations, a Pt-skin structure on AuCu(111) substrate, consisting of 1.5 monolayers of Pt, is found to have an appropriately weakened oxygen affinity, in comparison to that on Pt(111), which would be ideal for ORR catalysis. Such a structure is then realized by substituting the Cu atoms in three surface layers of AuCu intermetallic nanoparticles (AuCu iNPs) with Pt. The resulting Pt-skinned catalyst (denoted as Pt(S)AuCu iNPs) has been characterized in depth using synchrotron XRD, XPS, HRTEM, and HAADF-STEM/EDX, such that the Pt-skin structure is unambiguously identified. The thickness of the Pt skin was determined to be less than two atomic layers. Finally the catalytic activity of Pt(S)AuCu iNPs toward the ORR was measured via rotating disk electrode (RDE) voltammetry through which it was established that the SA was more than 2 times that of a commercial Pt/C catalyst. Taking into account the ultralow Pt loading in Pt(S)AuCu iNPs, the mass-specific catalytic activity (MA) was determined to be 0.56 A/mg(Pt)@0.9 V, a value that is well beyond the DOE 2017 target for ORR catalysts (0.44 A/mg(Pt)@0.9 V). These findings provide a strategic design and a realizable approach to high-performance and Pt-efficient catalysts for fuel cells.

12.
Phys Chem Chem Phys ; 16(38): 20618-23, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25158000

RESUMO

Albeit ultrahigh in energy density, the Li-O2 battery technology still suffers from the high overpotential of Li2O2 oxidation upon charging and the low cyclability. In the present work, we use Pt2Ru/C as the oxygen-electrode catalyst and study how it improves the cell performance and changes the reaction mechanism, as compared with a carbon electrode. Multiple methods, including X-ray diffraction, transmission/scanning electron microscopy, Raman spectroscopy, and cyclic voltammetry, have been employed for material characterization and reaction monitoring. The Li-O2 cell with a Pt2Ru/C catalyst shows lower charge voltage, higher specific capacity, and enhanced cyclability than does a carbon catalyst. The key for this improvement is ascribed to the morphology change of Li2O2. Whereas the Li2O2 formed in the carbon electrode is rod-shaped, the Li2O2 in the Pt2Ru/C electrode is mud shaped and closely attached to the electrode substrate, thus benefiting the subsequent Li2O2 oxidation. This study indicates that the charging performance of the Li-O2 battery can be improved not only by using proper catalysts, but also by controlling the Li2O2 morphology during discharge.

13.
Clin Nutr ESPEN ; 64: 215-220, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39396704

RESUMO

BACKGROUND & AIMS: The value of serum albumin might be underestimated, especially in cancer patients. We thus aimed to evaluate the association between serum albumin level at hospital admission and clinical outcomes in hospitalized patients with cancer. METHODS: This is a retrospective, cross-sectional, and real-world data analysis. Hospitalized adult patients with malignant cancer were recruited from two tertiary hospitals. Serum level of albumin, which was measured within 24 h after hospital admission, was the exposure. Length of hospital stays (LOS) was the primary and all-cause in-hospital mortality was the secondary outcomes. Other information, including age, sex, types of cancer, history of hypertension and diabetes, surgery, blood routine test, liver and renal function, and dietary intake, were also abstracted from medical records. RESULTS: A total number of 5187 adult patients with cancer (2949 were men and 2238 women; average age 61.6 ± 12.4 years and average albumin 40.3 ± 5.2 g/L) were included. The prevalence of hypoalbuminemia was 12.2 % (634/5187). Older patients, patients with liver injury, anemia, and with high level of WBC were positively, while those with overweight and high level of total triglycerides, were negatively associated with hypoalbuminemia. After adjustment of covariates, hypoalbuminemia was significantly associated with longer LOS in the current study. The increase of 5 g/L in serum level of albumin could result in 1.09 days (95%CI: -1.38, -0.80 days) shorter in LOS. The increase of 5 g/L in serum level of albumin was also associated with 45 % lower in risk of mortality (OR = 0.55; 95 % CI: 0.43, 0.7) after fully adjustment. CONCLUSIONS: Serum albumin level at admission was associated with both LOS and mortality in patients with malignant cancer.

14.
Genes Genomics ; 46(2): 241-252, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37747640

RESUMO

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is one of the most common malignancies and frequent cause of cancer-related death worldwide. Long non-coding RNAs (lncRNAs) play regulatory roles and serve as biomarkers of multiple cancers, including ESCC. Our previous studies have confirmed that lncRNA Kinectin 1 antisense RNA 1 (KTN1-AS1) is highly expressed in ESCC and exerts oncogene function through RBBP4/HDAC1 complex. OBJECTIVE: Our present study focused on exploring a novel molecular mechanism of KTN1-AS1 in ESCC. METHODS: In this study, qRT-PCR assay, Western blot assay, Luciferase reporter assay, and RNA immunoprecipitation assay were conducted. RESULTS: We found that KTN1-AS1 could bind to miR-885-5p in ESCC cells, and miR-885-5p was low expressed in ESCC. Overexpression of miR-885-5p inhibited esophageal cancer cells proliferation and invasion in vitro. Mechanistic analysis demonstrated that miR-885-5p specifically targeted striatin 3 (STRN3), and KTN1-AS1/miR-885-5p promoted the EMT process by Hippo pathway in STRN3/YAP1 dependent manner. CONCLUSION: To sum up, KTN1-AS1 facilitates ESCC progression by acting as a ceRNA for miR-885-5p to regulate STRN3 expression and the Hippo pathway, and KTN1-AS1 maybe used as a promising therapeutic target for ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , RNA Longo não Codificante , Humanos , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , RNA Antissenso/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Esofágicas/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Autoantígenos , Proteínas de Ligação a Calmodulina
15.
Transl Oncol ; 50: 102141, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39341066

RESUMO

Endoplasmic Reticulum Stress (ER stress) is a series of cellular responses activated in response to misfolded and unfolded protein accumulation and calcium imbalance in the ER lumen. Cumulating evidence emphasized the crucial involvement of ER stress in cell survival, death, and proliferation. However, the precise process remained obscure, especially in esophageal squamous cell carcinoma (ESCC). In the present study, LARP1B was detected to be one of the genes with significant differential expression in the ER stress ESCC cell model by RNA sequencing. ESCC cells exposed to ER stress stimulants (thapsigargin and tunicamycin) showed increased expression levels of LARP1B. ER stress initiated the expression of LARP1B through activation of the ERN1-XBP1 pathway, with XBP1 acting as a transcription factor to boost LARP1B transcription. Up-regulation of LARP1B was detected in ESCC tissues and cell lines. Suppression of LARP1B effectively curtailed the growth of cells and hindered the progression of the cell cycle. By detecting the expression of some genes closely related to proliferation and cell cycle regulation, CCND1 was identified as the main contributor to the cell proliferation induced by LARP1B. As an RNA-binding protein, LARP1B has the capability to attach to CCND1 mRNA, thereby increasing its stability. Inhibiting CCND1 might partially counterbalance the proliferation-promoting impact of LARP1B overexpression on ESCC cells. These findings indicate that, upon ER stress, up-regulation of LARP1B, triggered by ERN1-XBP1 pathway, facilitates proliferation of ESCC cells through enhancing the mRNA stability of CCND1, and LARP1B may be used as a potential therapeutic target of ESCC.

16.
Acc Chem Res ; 45(3): 473-81, 2012 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-22075175

RESUMO

Although the polymer electrolyte fuel cell (PEFC) is a superior power source for electric vehicles, the high cost of this technology has served as the primary barrier to the large-scale commercialization. Over the last decade, researchers have pursued lower-cost next-generation materials for fuel cells, and alkaline polymer electrolytes (APEs) have emerged as an enabling material for platinum-free fuel cells. To fulfill the requirements of fuel cell applications, the APE must be as conductive and stable as its acidic counterpart, such as Nafion. This benchmark has proved challenging for APEs because the conductivity of OH(-) is intrinsically lower than that of H(+), and the stability of the cationic functional group in APEs, typically quaternary ammonia (-NR(3)(+)), is usually lower than that of the sulfonic functional group (-SO(3)(-)) in acidic polymer electrolytes. To improve the ionic conductivity, APEs are often designed to be of high ion-exchange capacity (IEC). This modification has caused unfavorable changes in the materials: these high IEC APEs absorb excessive amounts of water, leading to significant swelling and a decline in mechanical strength of the membrane. Cross-linking the polymer chains does not completely solve the problem because stable ionomer solutions would not be available for PEFC assembly. In this Account, we report our recent progress in the development of advanced APEs, which are highly resistant to swelling and show conductivities comparable with Nafion at typical temperatures for fuel-cell operation. We have proposed two strategies for improving the performance of APEs: self-cross-linking and self-aggregating designs. The self-cross-linking design builds on conventional cross-linking methods and works for APEs with high IEC. The self-aggregating design improves the effective mobility of OH(-) and boosts the ionic conductivity of APEs with low IEC. For APEs with high IEC, cross-linking is necessary to restrict the swelling of the membrane. In our self-cross-linking design, a short-range cross-linker, tertiary amino groups, is grafted onto the quaternary ammonia polysulfone (QAPS) so that the cross-linking process can only occur during membrane casting. Thus, we obtain both the stable ionomer solution and the cross-linked membrane. The self-cross-linked QAPS (xQAPS) possesses a tight-binding structure and is highly resistant to swelling: even at 80 °C, the membrane swells by less than 3%. For APEs with low IEC, the key is to design efficient OH(-) conducting channels. In our self-aggregating design, long alkyl side-chains are attached to the QAPS. Based on both the transmission electron microscopy (TEM) observations and the molecular dynamics (MD) simulations, these added hydrophobic groups effectively drive the microscopic phase separation of the hydrophilic and hydrophobic domains and produce enlarged and aggregated ionic channels. The ionic conductivity of the self-aggregated QAPS (aQAPS) is three-fold higher than that of the conventional QAPS and is comparable to that of Nafion at elevated temperatures (e.g., greater than 0.1 S/cm at 80 °C).

17.
Langmuir ; 29(10): 3269-73, 2013 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-23414254

RESUMO

Traditionally, the meniscus bottom is taken as the fluid front when tracking the fluid motion in capillary, but in simulation studies, the thus-calculated motion curve deviates notably from the modified Lucas-Washburn equation. Here, we report that, by considering a volume equivalent of the meniscus part, the motion of the equivalent front agrees very well with the theoretical prediction; furthermore, such an effective fluid front can be directly represented by a specific position of the meniscus, which is independent of the capillary radius. These findings provide an accurate and practical method for describing the motion of the fluid front in capillary.

18.
Cell Death Dis ; 14(1): 72, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717549

RESUMO

LINC00941 is a novel long noncoding RNA (lncRNA) and emerging as an important factor in cancer development. However, the exact function and relative regulatory mechanism of LINC00941 in carcinogenesis of esophageal squamous cell carcinoma (ESCC) remain to be further clarified. The present study was to investigate the expression level, functions, and mechanisms of LINC00941 in ESCC tumorigenesis. LINC00941 was significantly upregulated in ESCC, and upregulated LINC00941 was correlated with dismal patient outcomes. LINC00941 functioned as an oncogene by promoting cells proliferation, stemness, migration, and invasion in ESCC. In terms of mechanisms, SOX2 could bind directly to the promoter region of LINC00941 and activate its transcription. In turn, LINC00941 upregulated SOX2 through interacting with interleukin enhancer binding factor 2 (ILF2) and Y-box binding protein 1 (YBX1) at the transcriptional and post-transcriptional levels. LINC00941 recruited ILF2 and YBX1 to the promoter region of SOX2, leading to upregulation of the transcription of SOX2. Moreover, LINC00941 could promote the binding ability of ILF2 and YBX1 on mRNA of SOX2 and further stabilize SOX2 mRNA. Therefore, LINC00941 contributed to the malignant behaviors of ESCC cells via the unrestricted increase in SOX2 expression. In conclusion, our data indicate that LINC00941 exacerbates ESCC progression through forming a LINC00941-ILF2/YBX1-SOX2 positive feedback loop, and LINC00941 may be a promising prognostic and therapeutic target for ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , RNA Longo não Codificante , Humanos , Carcinoma de Células Escamosas do Esôfago/patologia , Neoplasias Esofágicas/patologia , Linhagem Celular Tumoral , MicroRNAs/genética , RNA Mensageiro/genética , Regulação Neoplásica da Expressão Gênica/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proliferação de Células/genética , Movimento Celular/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo
19.
Sci Rep ; 13(1): 7737, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37173384

RESUMO

Esophageal squamous cell carcinoma (ESCC) is a serious malignancy with poor prognosis, necessitating identification of oncogenic mechanisms for novel therapeutic strategies. Recent studies have highlighted the significance of the transcription factor forkhead box K1 (FOXK1) in diverse biological processes and carcinogenesis of multiple malignancies, including ESCC. However, the molecular pathways underlying FOXK1's role in ESCC progression are not fully understood, and its potential role in radiosensitivity remains unclear. Here, we aimed to elucidate the function of FOXK1 in ESCC and explore the underlying mechanisms. Elevated FOXK1 expression levels were found in ESCC cells and tissues, positively correlated with TNM stage, invasion depth, and lymph node metastasis. FOXK1 markedly enhanced the proliferative, migratory and invasive capacities of ESCC cells. Furthermore, silencing FOXK1 resulted in heightened radiosensitivity by impeding DNA damage repair, inducing G1 arrest, and promoting apoptosis. Subsequent studies demonstrated that FOXK1 directly bound to the promoter regions of CDC25A and CDK4, thereby activating their transcription in ESCC cells. Moreover, the biological effects mediated by FOXK1 overexpression could be reversed by knockdown of either CDC25A or CDK4. Collectively, FOXK1, along with its downstream target genes CDC25A and CDK4, may serve as a promising set of therapeutic and radiosensitizing targets for ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Fatores de Transcrição Forkhead , Humanos , Fosfatases cdc25/genética , Fosfatases cdc25/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/radioterapia , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Prognóstico , Tolerância a Radiação/genética , Ativação Transcricional
20.
Chemphyschem ; 13(2): 514-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22184036

RESUMO

It is commonly recognized that the ionic conductivity of pure water is very poor because of very low ionic concentrations. However, this work indicates that pure water in charged porous matrixes can be moderately conductive because of the ions in the electric double layer established at the solid/water interfaces. The ionic conductivity of pure water in a charged matrix changes with the electrode potential of the matrix and is influenced by the structural parameters. Both experimental measurements and theoretical calculations reveal that ionic conductivity may reach the order of 10(-3) S cm(-1) in commonly accessible potential region in a porous matrix made of gold nanoparticles. These results would help to understand and optimize the electrode processes in electrochemical devices without deliberately added electrolytes, such as polymer electrolyte membrane fuel cells.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA