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1.
Nucleic Acids Res ; 51(17): 9166-9182, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37503842

RESUMO

Histone deacetylase 6 (HDAC6) mediates DNA damage signaling by regulating the mismatch repair and nucleotide excision repair pathways. Whether HDAC6 also mediates DNA double-strand break (DSB) repair is unclear. Here, we report that HDAC6 negatively regulates DSB repair in an enzyme activity-independent manner. In unstressed cells, HDAC6 interacts with H2A/H2A.X to prevent its interaction with the E3 ligase RNF168. Upon sensing DSBs, RNF168 rapidly ubiquitinates HDAC6 at lysine 116, leading to HDAC6 proteasomal degradation and a restored interaction between RNF168 and H2A/H2A.X. H2A/H2A.X is ubiquitinated by RNF168, precipitating the recruitment of DSB repair factors (including 53BP1 and BRCA1) to chromatin and subsequent DNA repair. These findings reveal novel regulatory machinery based on an HDAC6-RNF168 axis that regulates the H2A/H2A.X ubiquitination status. Interfering with this axis might be leveraged to disrupt a key mechanism of cancer cell resistance to genotoxic damage and form a potential therapeutic strategy for cancer.


Assuntos
Reparo do DNA , Humanos , Linhagem Celular Tumoral , Dano ao DNA , Desacetilase 6 de Histona/genética , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
2.
Phys Rev Lett ; 132(23): 233401, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38905656

RESUMO

Attempts to create quantum degenerate gases without evaporative cooling have been pursued since the early days of laser cooling, with the consensus that polarization gradient cooling (PGC, also known as "optical molasses") alone cannot reach condensation. In the present work, we report that simple PGC can generate a small Bose-Einstein condensate (BEC) inside a corrugated micrometer-sized optical dipole trap. The experimental parameters enabling BEC creation were found by machine learning, which increased the atom number by a factor of 5 and decreased the temperature by a factor of 2.5, corresponding to almost 2 orders of magnitude gain in phase space density. When the trapping light is slightly misaligned through a microscopic objective lens, a BEC of ∼250 ^{87}Rb atoms is formed inside a local dimple within 40 ms of PGC after MOT loading.

3.
Br J Dermatol ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38655652

RESUMO

OBJECTIVE: Psoriasis is a common, chronic inflammatory disease with unclear etiology. Keratinocytes in psoriasis are susceptible to exogenous triggers that induce inflammatory cell death. This study investigated whether GSDME-mediated pyroptosis in keratinocytes contributes to the pathogenesis of psoriasis. METHODS: Skin samples from patients with psoriasis and healthy controls were collected to evaluate the expression of GSDME, cleaved-caspase-3, and inflammatory factors. We then analyzed the data series, GSE41662, to further compare the expression of GSDME between lesional and non-lesional skin samples in those with psoriasis. In vivo, caspase-3 inhibitor and GSDME deficiency mice (Gsdme-/-) were applied to block caspase-3/GSDME activation in the imiquimod-induced psoriasis model. Skin inflammation, disease severity, and pyroptosis-related proteins were analyzed. In vitro, tumor necrosis factor-α (TNF-α)-induced caspase-3/GSDME-mediated pyroptosis in the HACAT cell line was explored. RESULTS: Our analysis of the GSE41662 data series found that GSDME were upregulated in psoriasis lesions, compared to normal skin. High levels of inflammatory cytokines such as IL-1ß, IL-6, and TNF-α were also found in psoriasis lesions. In mice of Gsdme-/- and caspase-3 inhibitor groups, the severity of skin inflammation was attenuated, and GSDME and C-caspase-3 levels decreased after imiquimod treatment. Similarly, IL-1ß, IL-6, and TNF-α were decreased in Gsdme-/- and caspase-3 inhibitor groups. In vitro, TNF-α induced HACAT cell pyroptosis through caspase-3/GSDME pathway activation, which was suppressed by blocking caspase-3 or silencing GSDME. CONCLUSION: Our study provides a novel explanation that TNF-α/caspase-3/GSDME-mediated keratinocyte pyroptosis is highly responsible for the initiation and acceleration of skin inflammation and progression of psoriasis.

4.
Health Econ ; 33(4): 604-635, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38104309

RESUMO

This paper studies how negative emotions like stress, anxiety, and boredom can affect unhealthy food consumption. Using the Wuhan lockdown as an external shock, we examine the changes in food consumption in a city that was not in lockdown. We applied the difference-in-differences method to a large scanner dataset from a retail monopoly in China. Our findings reveal that negative emotions induced by the pandemic lockdown significantly elevated consumer spending on unhealthy food items such as crisps, sugary beverages, regular soda, and low-alcohol beverages. Notably, the effect of unhealthy food consumption was more pronounced among younger and wealthier demographics. Triggering factors, like information about confirmed new deaths and infections as well as proximity to local hospitals, were found to strongly influence the consumption of unhealthy foods. Overall, the lockdown's impact extended beyond short-term increases in snack consumption to substantial increases in overall dietary and nutritional intake.


Assuntos
COVID-19 , Humanos , Controle de Doenças Transmissíveis , Bebidas , Bebidas Gaseificadas , Emoções
5.
Environ Toxicol ; 39(3): 1415-1428, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37987454

RESUMO

Epidemiologic surveys have indicated that cigarette smoking is an important risk factor for diabetes, but its mechanisms remain unclear. Andrographolide, an herb traditionally utilized in medicine, provides anti-inflammatory benefits for various diseases. In the present work, 265 patients with Type 2 diabetes (T2D) were investigated, and male C57BL/6 mice were exposed to cigareete smoke (CS) and/or to intraperitoneally injected andrographolide for 3 months. To elucidate the mechanism of CS-induced hyperglycemia and the protective mechanism of andrographolide, MIN6 cells were exposed to cigarette smoke extract (CSE) and/or to andrographolide. Our data from 265 patients with T2D showed that urinary creatinine and serum inflammatory cytokines (interleukin 6 (IL-6), IL-8, IL-1ß, and tumor necrosis factor α (TNF-α)) increased with smoking pack-years. In a mouse model, CS induced hyperglycemia, decreased insulin secretion, and elevated inflammation and pyroptosis in ß-cells of mice. Treatment of mice with andrographolide preserved pancreatic function by reducing the expression of inflammatory cytokines; the expression of TXNIP, NLRP3, cleaved caspase 1, IL-1ß; and the N-terminal of gasdermin D (GSDMD) protein. For MIN6 cells, CSE caused increasing secretion of the inflammatory cytokines IL-6 and IL-1ß, and the expression of TXNIP and pyroptosis-related proteins; however, andrographolide alleviated these changes. Furthermore, silencing of TXNIP showed that the blocking effect of andrographolide may be mediated by TXNIP. In sum, our results indicate that CS induces hyperglycemia through TXNIP-NLRP3-GSDMD axis-mediated inflammation and pyroptosis of islet ß-cells and that andrographolide is a potential therapeutic agent for CS-induced hyperglycemia.


Assuntos
Fumar Cigarros , Diabetes Mellitus Tipo 2 , Diterpenos , Hiperglicemia , Proteínas de Ligação a Fosfato , Humanos , Masculino , Camundongos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Interleucina-6/metabolismo , Camundongos Endogâmicos C57BL , Inflamação/metabolismo , Citocinas/metabolismo , Proteínas de Transporte , Gasderminas , Produtos do Tabaco
6.
Andrologia ; 54(1): e14250, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34644814

RESUMO

Obesity and overweight are independent risk factors of erectile dysfunction (ED). It is controversial whether weight loss can improve erectile function. We thereby performed this meta-analysis to clarify the therapeutic effect of weight loss on erectile function in overweight or obese men. Literature search was conducted on databases including Cochrane Library, Embase, Web of Science and PubMed to obtain all relevant English articles published before March 1, 2021. The primary outcome was final International Index of Erectile Function (IIEF) score or change in IIEF score. The secondary outcome was final body weight and body mass index (BMI) or change in body weight and BMI. After screening, 5 studies with 619 participants were enrolled in our meta-analysis. Our result showed that the mean difference in body weight between weight loss group and control group was -18.07 kg with p < .01, and the mean difference in BMI was -9.6 kg/m2 with p < .01. The mean difference of IIEF between weight loss group and control group was 1.99 with p < .01. This meta-analysis showed that weight loss could improve erectile function in overweight or obese men. Losing weight could serve as an adjuvant therapy for ED.


Assuntos
Disfunção Erétil , Sobrepeso , Disfunção Erétil/etiologia , Humanos , Masculino , Obesidade/complicações , Sobrepeso/complicações , Ereção Peniana , Ensaios Clínicos Controlados Aleatórios como Assunto , Redução de Peso
7.
Andrologia ; 54(11): e14583, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36123965

RESUMO

Idiopathic hypogonadotropic hypogonadism (IHH) is a rare genetically heterogeneous disease and characterized by incomplete or absent puberty and infertility. It is worth noting that partial IHH patients could recover reproductive endocrine function following treatment, which is termed reversal. This study aimed to investigate clinical and genetic characteristics of IHH reversal patients. A total of 141 IHH male patients were enrolled and followed up regularly. Their clinical and genetic features were collected and analysed to discover something in common in reversal cases. These IHH patients with a median age of 21 years (interquartile range: 18-24) were divided into reversal group (n = 13) and non-reversal group (n = 128). IL17RD, ERBB4, DLX5, EGFR, SEMA4D, B3GNT1 and CCKAR RSVs were demonstrated in reversal cases for the first time. Pathogenic/likely pathogenic (P/LP) RSVs consisted of 3 RSVs (one each patient, including PROKR2 p.W178S, EGFR p.G630R and CCKAR p.S291del) in reversal group. Reversal of IHH could not be ignored in clinical follow-up. Patients with high levels of basal LH and T may harbour more possibility of reversal and worthy extra attention to identify whether reversal occurs or not. Relapse after reversal also needs to be monitored.


Assuntos
Hipogonadismo , Adulto , Humanos , Masculino , Adulto Jovem , China , Estudos de Coortes , Hipogonadismo/tratamento farmacológico , Hipogonadismo/genética
8.
Phys Rev Lett ; 127(5): 050501, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34397223

RESUMO

We demonstrate a new approach for fast preparation, manipulation, and collective readout of an atomic Rydberg-state qubit. By making use of Rydberg blockade inside a small atomic ensemble, we prepare a single qubit within 3 µs with a success probability of F_{p}=0.93±0.02, rotate it, and read out its state in 6 µs with a single-shot fidelity of F_{d}=0.92±0.04. The ensemble-assisted detection is 10^{3} times faster than imaging of a single atom with the same optical resolution, and enables fast repeated nondestructive measurement. We observe qubit coherence times of 15 µs, much longer than the π rotation time of 90 ns. Potential applications ranging from faster quantum information processing in atom arrays to efficient implementation of quantum error correction are discussed.

9.
Int J Mol Sci ; 21(7)2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32252292

RESUMO

N6-methyladenosine (m6A) is the most prevalent internal modification present in the mRNAs of all higher eukaryotes, where it is present within both coding and noncoding regions. In mammals, methylation requires the catalysis of a multicomponent m6A methyltransferase complex. Proposed biological functions for m6A modification include pre-mRNA splicing, RNA stability, cell fate regulation, and embryonic development. However, few studies have been conducted on m6A modification in trees. In particular, the regulation mechanism of RNA m6A in Populus development remains to be further elucidated. Here, we show that PtrMTA (Populus trichocarpa methyltransferase) was colocalized with PtrFIP37 in the nucleus. Importantly, the PtrMTA-overexpressing plants significantly increased the density of trichomes and exhibited a more developed root system than that of wild-type controls. Moreover, we found that PtrMTA-overexpressing plants had better tolerance to drought stress. We also found PtrMTA was a component of the m6A methyltransferase complex, which participated in the formation of m6A methylation in poplar. Taken together, these results demonstrate that PtrMTA is involved in drought resistance by affecting the development of trichomes and roots, which will provide new clues for the study of RNA m6A modification and expand our understanding of the epigenetic molecular mechanism in woody plants.


Assuntos
Adaptação Biológica , Secas , Metiltransferases/genética , Desenvolvimento Vegetal , Raízes de Plantas/fisiologia , Populus/fisiologia , RNA Mensageiro/genética , Tricomas/genética , Regulação da Expressão Gênica de Plantas , Imuno-Histoquímica , Metiltransferases/metabolismo , Fenótipo , Desenvolvimento Vegetal/genética , Fenômenos Fisiológicos Vegetais , RNA Mensageiro/metabolismo , Estresse Fisiológico , Tricomas/metabolismo
10.
Med Sci Monit ; 25: 3762-3770, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31107859

RESUMO

BACKGROUND The WD repeat domain 5 (WDR5) is an essential component of methyltransferase complexes. The expression of WDR5 has been reported in several types of malignancy. This study aimed to investigate the expression of the WDR5 gene and protein in a human papillary carcinoma cell line in vitro, including the use WDR5 gene silencing, and the expression of the WDR5 protein in papillary thyroid carcinoma tissue, and clinicopathological characteristics including overall survival (OS). MATERIAL AND METHODS The role of WDR5 in proliferation and migration of the human papillary thyroid carcinoma cell line, KTC-1, was investigated using the cell counting kit-8 (CCK-8) assay and transwell assay after silencing WDR5 expression. Expression levels of WDR5 in 84 patients with papillary thyroid carcinoma were detected using immunohistochemistry. The correlation between WDR5 expression and clinicopathological features was analyzed using the chi-squared test. The prognostic role of WDR5 was evaluated by univariate analysis with the log-rank test, and by multivariate analysis with the Cox regression model. RESULTS WDR5 expression promoted the proliferation and migration of the KTC-1 cells. In tumor tissue from patients with papillary thyroid carcinoma, low expression and high expression levels of WDR5 were found in 72.6% and 27.4%, respectively. Increased expression of WDR5 was significantly associated with lymphatic invasion and reduced survival rates. WDR5 expression was an independent negative prognostic biomarker. CONCLUSIONS Expression of WDR5 promoted cell proliferation and migration in vitro and was associated with reduced prognosis in patients with papillary thyroid carcinoma.


Assuntos
Histona-Lisina N-Metiltransferase/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Adulto , Idoso , Povo Asiático/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Papilar/genética , Carcinoma Papilar/metabolismo , Carcinoma Papilar/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Progressão da Doença , Feminino , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Câncer Papilífero da Tireoide/metabolismo , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia
12.
Med Sci Monit ; 24: 7357-7365, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30319138

RESUMO

BACKGROUND SET and MYND domain-containing protein 2 (SMYD2), which is identified as a protein-lysine methyltransferase, plays a crucial role in the progression of some tumors such as bladder carcinoma. However, the clinical significance of SMYD2 in patients with papillary thyroid carcinoma (PTC) has not been elucidated. In the present study, we aimed to investigate the expression and role of SMYD2 in human PTC. MATERIAL AND METHODS Clinicopathological analysis was performed in 107 patients with PTC. Expression of SMYD2 was determined by immunohistochemistry staining, quantitative RT-PCR, or Western blotting in PTC tissues, adjacent normal tissues, and PTC cells (K1 and B-CPAP). The prognostic value of SMYD2 in PTC patients was assessed by univariate and multivariate analysis. Clinical outcomes were evaluated by Kaplan-Meier log-rank tests. Cell proliferation was examined in PTC cells following overexpression or knockdown of SMYD2. RESULTS SMYD2 was highly expressed in PTC tissues compared to adjacent thyroid tissues. Additionally, high expression of SMYD2 was significantly related to tumor size, lymph node metastasis, and TNM stage. Moreover, SMYD2 was identified as an independent prognosis factor by multivariate analysis. Using 2 PTC cell lines, K1 and B-CPAP, we demonstrated that high expression of SMYD2 can promote tumor cell proliferation. CONCLUSIONS SMYD2 expression was upregulated in PTC tissues and significantly related to the poorer prognosis of PTC patients. Our studies suggested the potential role of SMYD2 as a new therapeutic target and prognostic biomarker in human PTC.


Assuntos
Histona-Lisina N-Metiltransferase/biossíntese , Câncer Papilífero da Tireoide/enzimologia , Adulto , Idoso , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Progressão da Doença , Feminino , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Câncer Papilífero da Tireoide/genética , Transcriptoma , Regulação para Cima
13.
Pak J Pharm Sci ; 31(3(Special)): 1103-1107, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29735458

RESUMO

The goal of diabetic drug treatment is to stabilize the blood sugar for a long time to close to the normal level, to correct the metabolic disorder and eliminate the symptoms. At present, glimepiride has become commonly used drugs for the treatment of diabetes with obesity. Compared with metformin, acarbose and rosiglitazone, glimepiride has different mechanisms of drug action, clinical combination showed synergistic hypoglycemic effect, good clinical curative effect. So, we use three treatments to study as group A (glimepiride and metformin); group B (glimepiride and acarbose); Group C (glimepiride and rosiglitazone). From the analysis of drug economics, glimepiride and metformin scheme is better, has the lowest cost per unit cost effect. From the comparison of scheme is efficient, the best curative effect is rosiglitazone plus glimepiride, effective rate as 96.7%. At the same time, the drug can be rationally used to reduce the occurrence of some drug-induced diseases and adverse drug reactions.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Farmacoeconomia , Compostos de Sulfonilureia/administração & dosagem , Compostos de Sulfonilureia/uso terapêutico , Acarbose/administração & dosagem , Acarbose/economia , Acarbose/uso terapêutico , Adulto , Glicemia , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/economia , Hipoglicemiantes/uso terapêutico , Masculino , Metformina/administração & dosagem , Metformina/economia , Metformina/uso terapêutico , Pessoa de Meia-Idade , Rosiglitazona/administração & dosagem , Rosiglitazona/economia , Rosiglitazona/uso terapêutico , Compostos de Sulfonilureia/economia
14.
Water Resour Res ; 53(9): 7885-7903, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-29200529

RESUMO

This paper explores the impacts of a water right's allocative priority-as an indicator of farmers' risk-bearing ability-on land irrigation under water supply uncertainty. We develop and use an economic model to simulate farmers' land irrigation decision and associated economic returns in eastern Idaho. Results indicate that the optimal acreage of land irrigated increases with water right priority when hydroclimate risk exhibits a negatively skewed or right-truncated distribution. Simulation results suggest that prior appropriation enables senior water rights holders to allocate a higher proportion of their land to irrigation, 6 times as much as junior rights holders do, creating a gap in the annual expected net revenue reaching up to $141.4 acre-1 or $55,800 per farm between the two groups. The optimal irrigated acreage, expected net revenue, and shadow value of a water right's priority are subject to substantial changes under a changing climate in the future, where temporal variation in water supply risks significantly affects the profitability of agricultural land use under the priority-based water sharing mechanism.

15.
Arch Toxicol ; 90(2): 449-61, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25526925

RESUMO

Abnormal expression of miRNAs has been implicated in the pathogenesis of human lung cancers, most of which are attributable to cigarette smoke. The mechanisms of action, however, remain obscure. Here, we report that there are decreased expression of miR-218 and increased expression of EZH2 and H3K27me3 during cigarette smoke extract (CSE)-induced transformation of human bronchial epithelial (HBE) cells. Depletion of EZH2 by siRNA or by the EZH2 inhibitor, 3-deazaneplanocin A, attenuated CSE-induced decreases of miR-218 levels and increases of H3K27me3, which epigenetically controls gene transcription, and BMI1, an oncogene. Furthermore, ChIP assays demonstrated that EZH2 and H3K27me3 are enriched at the miR-218-1 promoter in HBE cells exposed to CSE, indicating that EZH2 mediates epigenetic silencing of miR-218 via histone methylation. In addition, miR-218 directly targeted BMI1, through which miR-218 ablates cancer stem cells (CSCs) self-renewal in transformed HBE cells. In CSE-transformed HBE cells, the protein level of Oct-4 and mRNA levels of CD133 and CD44, indicators of the acquisition of CSC-like properties, were reduced by over-expression of miR-218, and over-expression of miR-218 decreased the malignancy of transformed HBE cells. Thus, we conclude that epigenetic silencing of miR-218 via EZH2-mediated H3K27 trimethylation is involved in the acquisition of CSC-like properties and malignant transformation of HBE cells induced by CSE and thereby contributes to the carcinogenesis of cigarette smoke.


Assuntos
Transformação Celular Neoplásica/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , MicroRNAs/genética , Fumar/efeitos adversos , Brônquios/citologia , Linhagem Celular , Transformação Celular Neoplásica/efeitos dos fármacos , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Epigênese Genética/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Humanos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/patologia , Lisina/metabolismo , Metilação/efeitos dos fármacos , Proteína Quinase 7 Ativada por Mitógeno/genética , Proteína Quinase 7 Ativada por Mitógeno/metabolismo
16.
Mol Carcinog ; 54 Suppl 1: E148-61, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25252218

RESUMO

Lung cancer is the leading cause of cancer mortality worldwide. A common interest in lung cancer research is the identification of biomarkers for early diagnosis and accurate prognosis. There is increasing evidence that microRNAs (miRNAs) are involved in lung cancer. To explore new biomarkers of chemical exposure in risk assessment of chemical carcinogenesis and lung cancer, we analyzed miRNA expression profiles of human bronchial epithelial (HBE) cells malignantly transformed by arsenite. High-throughput microarray analysis showed that 51 miRNAs were differentially expressed in transformed HBE cells relative to normal HBE cells. In particular, miR-191 was up-regulated in transformed cells. In HBE cells, arsenite induced increases of miR-191 and WT1 levels, decreased BASP1 expression, and activated the Wnt/ß-catenin pathway, effects that were blocked by miR-191 knockdown. In addition, a luciferase reporter assay indicated that BASP1 is a direct target of miR-191. By inhibiting the expression of BASP1, miR-191 increased the expression of WT1 to promote activation of Wnt/ß-catenin pathway. In transformed cells, inhibition of miR-191 expression blocked the epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC)-like properties of cells and decreased their migratory capacity and neoplastic properties. Thus, these results demonstrate that miR-191 modulates the EMT and the CSC-like properties of transformed cells and indicate that it is an onco-miR involved in the neoplastic and metastatic properties of transformed cells.


Assuntos
Neoplasias Brônquicas/patologia , Transição Epitelial-Mesenquimal/fisiologia , MicroRNAs/fisiologia , Metástase Neoplásica , Células-Tronco Neoplásicas/patologia , Sequência de Bases , Neoplasias Brônquicas/genética , Linhagem Celular Transformada , Primers do DNA , Humanos , MicroRNAs/genética , Reação em Cadeia da Polimerase em Tempo Real
17.
Toxicol Appl Pharmacol ; 282(1): 9-19, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25447409

RESUMO

The incidence of lung diseases, including cancer, caused by cigarette smoke is increasing, but the molecular mechanisms of gene regulation induced by cigarette smoke remain unclear. This report describes a long noncoding RNA (lncRNA) that is induced by cigarette smoke extract (CSE) and experiments utilizing lncRNAs to integrate inflammation with the epithelial-mesenchymal transition (EMT) in human bronchial epithelial (HBE) cells. The present study shows that, induced by CSE, IL-6, a pro-inflammatory cytokine, leads to activation of STAT3, a transcription activator. A ChIP assay determined that the interaction of STAT3 with the promoter regions of HOX transcript antisense RNA (HOTAIR) increased levels of HOTAIR. Blocking of IL-6 with anti-IL-6 antibody, decreasing STAT3, and inhibiting STAT3 activation reduced HOTAIR expression. Moreover, for HBE cells cultured in the presence of HOTAIR siRNA for 24h, the CSE-induced EMT, formation of cancer stem cells (CSCs), and malignant transformation were reversed. Thus, IL-6, acting on STAT3 signaling, which up-regulates HOTAIR in an autocrine manner, contributes to the EMT and to CSCs induced by CSE. These data define a link between inflammation and EMT, processes involved in the malignant transformation of cells caused by CSE. This link, mediated through lncRNAs, establishes a mechanism for CSE-induced lung carcinogenesis.


Assuntos
Transformação Celular Neoplásica/metabolismo , Células Epiteliais/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Pulmonares/etiologia , Pulmão/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , RNA Longo não Codificante/metabolismo , Fumaça/efeitos adversos , Fumar/efeitos adversos , Animais , Comunicação Autócrina/efeitos dos fármacos , Linhagem Celular Transformada , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Relação Dose-Resposta a Droga , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Interleucina-6/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Interferência de RNA , RNA Longo não Codificante/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção , Regulação para Cima
18.
Arch Toxicol ; 89(7): 1071-82, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24912785

RESUMO

Intercellular communications within the cancer microenvironment coordinate the assembly of various cell types. Exosomes are mediators of intercellular communication in immune signaling, tumor promotion, stress responses, and angiogenesis. The present research aimed to determine whether miRNAs secreted from human bronchial epithelial (HBE) cells transformed by 1.0 µM arsenite are transferred into normal HBE cells and are functionally active in the recipient cells. The results show that miR-21 is involved in exosome-mediated intercellular communication between neoplastic and normal HBE cells. Exosomes derived from transformed HBE cells stimulated proliferation of normal HBE cells, whereas exosomes from miR-21 depleted cells failed to stimulate proliferation. In normal HBE cells, the expression of phosphatase and tensin homolog, a target gene for miR-21, was increased by exosomal miR-21, indicating that exogenous miRNAs, via exosomal transport, function-like endogenous miRNAs. Concordantly, specific reduction of miR-21 content in exosome-producing transformed cells abolished the stimulation of proliferation by exosomes. Collectively, the data indicate that transformed HBE cells release exosomes containing miR-21, stimulating proliferation in neighboring normal HBE cells and supporting the concept that exosomal miRNAs are involved in cell-cell communication during carcinogenesis induced by environmental chemicals.


Assuntos
Arseniatos/toxicidade , Brônquios/efeitos dos fármacos , Proliferação de Células , Transformação Celular Neoplásica/induzido quimicamente , Células Epiteliais/efeitos dos fármacos , Exossomos/efeitos dos fármacos , MicroRNAs/metabolismo , Comunicação Parácrina/efeitos dos fármacos , Brônquios/metabolismo , Brônquios/patologia , Linhagem Celular Transformada , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Técnicas de Cocultura , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Exossomos/metabolismo , Humanos , Interleucina-6/metabolismo , MicroRNAs/genética , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Interferência de RNA , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção , Regulação para Cima
19.
J Appl Stat ; 51(1): 34-52, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38179164

RESUMO

The Sharpe ratio function is a commonly used risk/return measure in financial econometrics. To estimate this function, most existing methods take a two-step procedure that first estimates the mean and volatility functions separately and then applies the plug-in method. In this paper, we propose a direct method via local maximum likelihood to simultaneously estimate the Sharpe ratio function and the negative log-volatility function as well as their derivatives. We establish the joint limiting distribution of the proposed estimators, and moreover extend the proposed method to estimate the multivariate Sharpe ratio function. We also evaluate the numerical performance of the proposed estimators through simulation studies, and compare them with existing methods. Finally, we apply the proposed method to the three-month US Treasury bill data and that captures a well-known covariate-dependent effect on the Sharpe ratio.

20.
Neural Netw ; 170: 521-534, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043372

RESUMO

Image Salient Object Detection (SOD) is a fundamental research topic in the area of computer vision. Recently, the multimodal information in RGB, Depth (D), and Thermal (T) modalities has been proven to be beneficial to the SOD. However, existing methods are only designed for RGB-D or RGB-T SOD, which may limit the utilization in various modalities, or just finetuned on specific datasets, which may bring about extra computation overhead. These defects can hinder the practical deployment of SOD in real-world applications. In this paper, we propose an end-to-end Unified Triplet Decoder Network, dubbed UTDNet, for both RGB-T and RGB-D SOD tasks. The intractable challenges for the unified multimodal SOD are mainly two-fold, i.e., (1) accurately detecting and segmenting salient objects, and (2) preferably via a single network that fits both RGB-T and RGB-D SOD. First, to deal with the former challenge, we propose the multi-scale feature extraction unit to enrich the discriminative contextual information, and the efficient fusion module to explore cross-modality complementary information. Then, the multimodal features are fed to the triplet decoder, where the hierarchical deep supervision loss further enable the network to capture distinctive saliency cues. Second, as to the latter challenge, we propose a simple yet effective continual learning method to unify multimodal SOD. Concretely, we sequentially train multimodal SOD tasks by applying Elastic Weight Consolidation (EWC) regularization with the hierarchical loss function to avoid catastrophic forgetting without inducing more parameters. Critically, the triplet decoder separates task-specific and task-invariant information, making the network easily adaptable to multimodal SOD tasks. Extensive comparisons with 26 recently proposed RGB-T and RGB-D SOD methods demonstrate the superiority of the proposed UTDNet.


Assuntos
Sinais (Psicologia)
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