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1.
Am J Cancer Res ; 13(7): 2969-2983, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37560002

RESUMO

Globo-H (GH), a globo-series glycosphingolipid antigen that is synthesized by key enzymes ß1,3-galactosyltransferase V (ß3GalT5), fucosyltransferase (FUT) 1 and 2, is highly expressed on a variety of epithelial cancers rendering it a promising target for cancer immunotherapy. GH-targeting antibody-drug conjugate has been demonstrated an excellent tumor growth inhibition potency in animal models across multiple cancer types including Gastric cancer (GC). This study aims to further investigate the GH roles in GC. Significant correlations were observed between high mRNA expression of GH-synthetic key enzymes and worse overall survival (OS)/post-progression survival for GC patients based on the data from "Kaplan-Meier plotter" database (n=498). The level of GH expression was evaluated in clinical adenocarcinoma samples from 105 patients with GC by immunohistochemistry based on H-score. GH expression (H score ≥ 20; 33.3%) was significantly associated with a poor disease specific survival (DSS) and invasiveness in all samples with P=0.029 and P=0.013, respectively. In addition, it is also associated with shorter DSS and OS in poorly differentiated tumors with P=0.033 and P=0.045, respectively. Particularly, with patients ≥ 65 years of age, GH expression is also significantly associated with the stages (P=0.023), differentiation grade (P=0.038), and invasiveness (P=0.026) of the cancer. Sorted GC NCI-N87 cells with high level of endogenous GH showed higher proliferative activity compared with low-GH-expressing cells based on PCNA expression. Micro-western array analysis on high-GH-expressing GC cells indicated an upregulation in HER2-related signaling proteins including phospho-AKT/P38/JNK and Cyclin D1/Cyclin E1 proteins. Moreover, GH level was shown to be correlated with expression of total HER2 and caveolin-1 in GC cells. Immunoprecipitation study suggested that there are potential interactions among GH, caveolin-1, and HER2. In conclusions, GH level was significantly associated with the worse survival and disease progression in GC patients, especially in older patients. Enhanced cell proliferation activity through interactions among GH, HER2, and caveolin-1 interactions may contribute to GH induced tumor promotion signaling in GC. GH-targeting therapy may be a viable option for the treatment of GC patients.

2.
Materials (Basel) ; 16(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36902994

RESUMO

In engineering acoustics, the propagation of elastic flexural waves in plate and shell structures is a common transmission path of vibrations and structure-borne noises. Phononic metamaterials with a frequency band gap can effectively block elastic waves in certain frequency ranges, but often require a tedious trial-and-error design process. In recent years, deep neural networks (DNNs) have shown competence in solving various inverse problems. This study proposes a deep-learning-based workflow for phononic plate metamaterial design. The Mindlin plate formulation was used to expedite the forward calculations, and the neural network was trained for inverse design. We showed that, with only 360 sets of data for training and testing, the neural network attained a 2% error in achieving the target band gap, by optimizing five design parameters. The designed metamaterial plate showed a -1 dB/mm omnidirectional attenuation for flexural waves around 3 kHz.

3.
PLoS One ; 17(10): e0274425, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36201438

RESUMO

No previous research has examined cognitive-motor interference (CMI) repeatedly in patients with subacute stroke. This pilot study aimed to report on the changes over time in CMI in patients with stroke who have recently learned to walk with a cane. The assessment started as soon as the participants could walk independently with a quad cane, and was repeated up to six sessions as long as the cane was still used. The dual-tasking paradigm required participants to walk and perform continuous subtractions by 3s. Data were analyzed for 9 participants 33-127 days post-stroke. All 9 participants showed CMI in walking velocity at baseline and 8 of these showed improvement over time (Z = -2.547; p = 0.011). The improvement in CMI was associated with baseline dual-tasking performance (ρ = 0.600; p = 0.044), motor control ability (ρ = -0.695; p = 0.019), walking velocity (ρ = -0.767; p = 0.008), and functional mobility (ρ = 0.817; p = 0.004). All participants showed decrements in both tasks (mutual interference) at baseline, 1 evolved to decrements in walking velocity (cognitive-related motor interference), and 3 finally evolved to decrements in cognitive performance but increments in walking velocity (motor-priority tradeoff). In conclusion, during rehabilitation with cane walking in patients with subacute stroke, the dual-tasking paradigm revealed CMI and its improvements in the majority of participants. Greater improvement in CMI was moderately to strongly associated with worse baseline performance of many variables. The evolution of the CMI pattern over time provides novel information relevant to neurological recovery.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Bengala , Cognição , Marcha , Humanos , Projetos Piloto , Desempenho Psicomotor , Caminhada
4.
Front Pharmacol ; 13: 754271, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034808

RESUMO

Acute pulmonary embolism (APE) is a debilitating condition with high incidence and mortality rates. APE is widely treated with the serine protease urokinase or urokinase-type plasminogen activator (uPA) that functions by resolving blood clots via catalyzing the conversion of plasminogen to plasmin. Treatment with recombinant uPA has been shown to increase endogenous expression of uPA and its cognate receptor, uPAR; however, the mechanisms for this induction are not known. Using an in vitro hypoxia/reoxygenation model in bronchial epithelial BEAS-2B cells, we show that induction of hypoxia/reoxygenation induces apoptosis and increases secretion of tumor necrosis factor-alpha, brain natriuretic peptide, and fractalkine, which are attenuated when treated with exogenous uPA. Induction of hypoxia/reoxygenation resulted in decreased expression of uPAR on cell surface without any significant changes in its messenger RNA expression, highlighting post-transcriptional regulatory mechanisms. Determination of uPAR protein half-life using cycloheximide showed treatment with uPA significantly increased its half-life (209.6 ± 0.2 min from 48.2 ± 2.3 min). Hypoxia/reoxygenation promoted the degradation of uPAR. Inhibition of proteasome-mediated degradation using MG-132 and lactacystin revealed that uPAR was actively degraded when hypoxia/reoxygenation was induced and that it was reversed when treated with exogenous uPA. Determination of the proteolytic activity of 20S proteasome showed a global increase in ubiquitin-proteasome activation without an increase in proteasome content in cells subjected to hypoxia/reoxygenation. Our results cumulatively reveal that uPAR is actively degraded following hypoxia/reoxygenation, and the degradation was significantly weakened by exogenous uPA treatment. Given the importance of the uPA/uPAR axis in a multitude of pathophysiological contexts, these findings provide important yet undefined mechanistic insights.

5.
Front Pharmacol ; 13: 713848, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571119

RESUMO

Acute pulmonary embolism (APE) is a disabling diseases with high incidence rate and mortality rate. Although with high specificity, D-Dimer lacks specificity to assess APE, hence additional diagnostic and prognostic biomarkers are necessary. APE is widely treated with serine protease urokinase or urokinase-type plasminogen activator (uPA), which act as a catalyst for conversion of plasminogen to plasmin to resolve blood clots. However, it is unknown the role of differential expression of microRNAs (miRNAs) in protective effect of uPA against APE. Hence, we performed miRNA profiling in a hypoxia/reoxygenation (H/R) model of bronchial epithelial BEAS-2B cells in vitro and a APE mice model in vivo. Our analysis revealed that miR-34a-5p, miR-324-5p, miR-331-3p are upregulated with H/R or APE induction, whereas miR-429, miR-491-5p, and miR-449a are downregulated. The differential expression of the miRNAs was attenuated to levels comparable to control by treatment with uPA both in vitro and in vivo. In situ target prediction and analysis of potential functions of the target genes showed that the enrichment of biological processes and pathways were related to cell growth, proliferation, and inflammation. Ectopic overexpression of miR-449a using a mimic completely attenuated the protective effect of uPA in the H/R model in vitro. These results provide a group of miRNAs that could be used as markers, and the modulation of these miRNAs might have potential therapeutic benefits in patients with APE, which need to be validated in additional studies in humans.

6.
Materials (Basel) ; 15(7)2022 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-35407795

RESUMO

Zr-Cu based thin-film metallic glass (TFMG) has good glass-forming ability and the addition of a third element can create a chaotic system capable of inhibiting the nucleation and growth of crystals. This study focused on TFMGs made with Zr, Cu, and Ti in various compositions deposited via high-impulse magnetron sputtering on silicon and 304 stainless-steel substrates. Detailed analysis was performed on the microstructure and surface characteristics of the resulting coatings. Transmission electron microscopy revealed that the multilayer structure changed to a nanocrystalline structure similar to an amorphous coating. The excellent hydrophobicity of Zr-Cu-Ti TFMGs can be attributed to their ultra-smooth surface without any grain boundaries. The excellent antimicrobial effects can be attributed to a hydrophobic surface resisting cell adhesion and the presence of copper ions, which are lethal to microbes.

7.
Adv Mater ; 33(9): e2005160, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33470488

RESUMO

In conventional theories, topological band properties are intrinsic characteristics of the bulk material and do not depend on the choice of the reference frame. In this scenario, the principle of bulk-edge correspondence can be used to predict the existence of edge states between topologically distinct materials. In this study, a 2D elastic phononic plate is proposed with a Kekulé-distorted honeycomb pattern engraved on it. It is found that the pseudospin and the pseudospin-dependent Chern numbers are not invariant properties, and the ℤ 2 number is no longer a sufficient indicator to examine the existence of the edge state. The distinctive pseudospin texture and the pseudomagnetic field are also revealed. Finally, the synthetic helical edge states are successfully devised and experimentally implemented on a dislocation interface connecting two subdomains with bulk pattern identical up to a relative translation. The edge state is also imaged via laser vibrometry.

8.
IUBMB Life ; 72(8): 1725-1736, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32534478

RESUMO

The endogenous non-coding microRNA (miRNA) let-7b-5p is highly expressed in the blood of patients with acute pulmonary embolism (PE). However, the mechanism underlying the involvement of let-7b-5p in acute PE remains unclear. To address this, we investigated the role of let-7b-5p in acute PE in both in vitro and in vivo experimental models. The results showed that let-7b-5p upregulated the expression of stress-associated endoplasmic reticulum protein 1 (SERP1) at the post-transcriptional level. SERP1 activation leads to modulation of its chaperone protein SEC61B in the response of endoplasmic reticulum (ER) stress. Furthermore, our data show that the unfolded protein response was triggered and activation of unfolded proteins GRP78, PERK, RNF121, and CHOP occurred through the PERK-CHOP pathway, resulting in an inflammatory response and apoptosis of lung epithelial cells. These characteristics were promoted by the in vitro expression of a let-7b-5p mimic; conversely, transfection with a let-7b-5p inhibitor decreased the response of ER stress in acute PE. The results from this study thus provide evidence that let-7b-5p promotes protein processing during ER stress response by upregulating SERP1 expression, ultimately resulting in an inflammatory response and apoptosis of lung cells, cumulatively playing a critical role in the pathogenesis of acute PE.


Assuntos
Proteínas de Membrana/genética , MicroRNAs/genética , Embolia Pulmonar/genética , Canais de Translocação SEC/genética , Apoptose/genética , Retículo Endoplasmático/genética , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/genética , Regulação da Expressão Gênica/genética , Proteínas de Choque Térmico/genética , Humanos , Embolia Pulmonar/patologia , Fator de Transcrição CHOP/genética , eIF-2 Quinase/genética
9.
J Thorac Dis ; 10(12): 6921-6931, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30746238

RESUMO

BACKGROUND: The aim of this study is to determine the role of nuclear factor kappa B (NF-κB)-mediated c-Jun N-terminal kinase (JNK) pathway in cognitive impairment induced by chronic intermittent hypoxia (CIH). METHODS: Ninety-six male Sprague-Dawley rats were randomly divided into 8 groups: sham group, sustained hypoxia (SH) group, CIH group, CIH + melatonin group, CIH + vitamin E group, CIH + DMSO group, CIH + BAY 11-7082 group and CIH + normal saline (NS) group. Rats were exposed to normoxia, CIH (21% O2 for 60 s and 10% O2 for 60 s, cyclically repeated for 10 h/day) or SH (10% O2 for 10 h/day) for 14 days. Afterwards, Morris water maze test was conducted, and serum and hippocampus tissues were subjected to molecular biological and biochemical analyses. RESULTS: Compared with the Sham and SH group, oxidative stress was induced by CIH in rat hippocampus with the high level of malondialdehyde (MDA) and 8-iso-PGF2α and the low level of superoxide dismutase (SOD) and glutathione (GSH). Activated NF-κB and its downstream products including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and inducible nitric oxide synthase (iNOS) were highly expressed in CIH rats. These changes were attenuated by pretreatment of the rats with melatonin and vitamin E. CIH also resulted in hippocampus neuron apoptosis with increased caspase 3 level, dUIP nick end labeling (TUNEL)-positive neurons number and cognitive impairment verified by prolonged latency and shortened time in the target quadrant in Morris water maze test. JNK and its downstream transcriptional factors including c-Jun, activating transcription factor 2 (ATF2), and JunD were all significantly phosphorylated in CIH rats. However, pretreatment of NF-κB inhibitor BAY 11-7082 inhibited the activation of NF-κB under CIH condition and also significantly reduced the phosphorylation of JNK as well as c-Jun, ATF2, and JunD. Moreover, hippocampus neuron apoptosis and cognitive impairment were significantly improved with the pretreatment of BAY 11-7082 in rats subjected to CIH. CONCLUSIONS: These findings suggest that NF-κB-mediated JNK pathway is at least partially implicated in CIH-induced hippocampus neuron apoptosis and cognitive impairment. Inhibition of NF-κB activation provided a therapeutic potential for cognitive impairment in sleep apnea (SA).

10.
J Biosci Bioeng ; 124(1): 108-114, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28286121

RESUMO

Glucose is a carbon source for Chinese hamster ovary (CHO) cell growth, while low growth rate is considered to enhance the production of recombinant proteins. The present study reveals that glucose concentrations higher than 1 g/L reduce the growth rate and substantially increase in cAMP (∼300%) at a high glucose concentration (10 g/L). High glucose also enhances the phosphorylation of extracellular signal-regulated kinase (ERK) and p27kip by Western blot analysis. To determine whether the phosphorylation of ERK is involved in the mechanism, a cyclic-AMP dependent protein kinase A (PKA) inhibitor (H-8) or MEK (MAPKK) inhibitor (PD98059) was added to block ERK phosphorylation. We show that both the high glucose-induced ERK phosphorylation and growth rate return to baseline levels. These results suggest that the cAMP/PKA and MAP signaling pathways are involved in the abovementioned mechanism. Interestingly, the direct addition of 8-bromo-cAMP (Br-cAMP), a membrane-permeable cAMP analog, can mimic the similar effects produced by high glucose. Subsequently Br-cAMP could induce ß-galactosidase (ß-Gal) recombinant protein expression by 1.6-fold. Furthermore, Br-cAMP can additionally enhance the ß-Gal production (from 2.8- to 4.5-fold) when CHO cells were stimulated with glycerol, thymidine, dimethyl sulfoxide, pentanoic acid, or sodium butyrate. Thus, Br-cAMP may be used as an alternative agent in promoting foreign protein expression for CHO cells.


Assuntos
8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , AMP Cíclico/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glucose/farmacologia , beta-Galactosidase/genética , Animais , Células CHO , Cricetinae , Cricetulus , Relação Dose-Resposta a Droga , Expressão Gênica , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
11.
Biotechnol Prog ; 28(6): 1566-74, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23011767

RESUMO

Dissociated primary neuron culture has been the most widely used model systems for neuroscience research. Most of these primary neurons are cultured on adhesion matrix-coated surface to provide a proper environment for cell anchorage under serum-free conditions. In this study, we provide an alternative technique to promote the adhesions of these neurons using aurintricarboxylic acid (ATA), a nonpeptide compound, without surface manipulations. We first demonstrated that ATA could promote Chinese hamster ovary cell attachment and proliferation in serum-free medium in a dosage-dependent manner. We later showed that ATA significantly enhanced the attachment of the retinoic acid differentiated P19 mouse embryonal carcinoma (P19) neurons, with an optimal concentration around 30 µg/mL. A similar result was seen in primary hippocampal neurons, with an optimal ATA concentration around 15 µg/mL. Further morphological assessments revealed that the average neurite length and neuronal polarization were almost identical to that obtained using a conventional method with poly-L-lysine surface. The advantages of using the ATA treatment technique for immunochemical analysis are discussed.


Assuntos
Ácido Aurintricarboxílico/farmacologia , Adesão Celular/efeitos dos fármacos , Técnicas de Cultura de Células/métodos , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Actinas/metabolismo , Análise de Variância , Animais , Células CHO , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Meios de Cultura Livres de Soro , Camundongos , Camundongos Endogâmicos C57BL , Propriedades de Superfície , Tretinoína/farmacologia , Tubulina (Proteína)/metabolismo
12.
J Nanosci Nanotechnol ; 10(8): 5170-4, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21125866

RESUMO

We report the hardness of wurtzite InN thin film grown with different crystalline orientations of heteroepitaxial s-plane (1101) and a-plane (1120) on r-plane (1102) Al2O3, and homoepitaxial film on c-plane (0001) Al2O3. Hardness values along with elastic properties are studied using nanoindentation technique. Maximum hardness is reported for c-plane (approximately 8 GPa), which is followed by s-plane (approximately 5.5 GPa) and then a-plane (approximately 4 GPa) oriented InN Films. Peierls force in the slip system of different crystalline orientations for wurtzite sample is calculated for explaining the systematic variations in hardness values of these films grown with different crystalline orientations.

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