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1.
Polymers (Basel) ; 16(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38276711

RESUMO

Wood fibers (WFs) were treated at a fixed heat temperature (180 °C) for 2-6 h and added to a polylactic acid (PLA) matrix to produce wood-PLA composite (WPC) filaments. Additionally, the effects of the heat-treated WFs on the physicomechanical properties and impact strength of the WPC filaments and 3D-printed WPC parts using fused filament fabrication (FFF) were examined. The results revealed that heat-treated WFs caused an increase in crystallinity and a significant reduction in the number of pores on the failure cross section of the WPC filament, resulting in a higher tensile modulus and lower elongation at break. Additionally, the printed WPC parts with heat-treated WFs had higher tensile strength and lower water absorption compared to untreated WPC parts. However, most of the mechanical properties and impact strength of 3D-printed WPC parts were not significantly influenced by adding heat-treated WFs. As described above, at the fixed fiber addition amount, adding heat-treated WFs improved the dimensional stability of the WPC parts and it enabled a high retention ratio of mechanical properties and impact strength of the WPC parts.

2.
Adv Sci (Weinh) ; 10(21): e2207731, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37196431

RESUMO

The demand for highly specific and complex materials has made the development of controllable manufacturing processes crucial. Among the numerous manufacturing methods, casting is important because it is economical and highly flexible regarding the geometry of manufactured parts. Since solidification is an important stage in the casting process that influences the properties of the final product, the development of a controllable solidification process using modeling methods is necessary to create superior structural properties. However, traditional modeling methods are computationally expensive and require sophisticated mathematical schemes. Therefore, a deep learning model is proposed to predict the morphology of the dendritic crystal growth solidification process, along with a reinforcement learning model to control the solidification process. By training the deep learning model with data generated using the phase field method, the solidification process can be successfully predicted. The crystal growth structures are designed to be altered by adjusting the degree of supercooling in the deep learning model while implementing reinforcement learning to control the dendritic arteries. This research opens new avenues for applying artificial intelligence to the optimization of casting processes, with the potential to utilize it in the processing of advanced materials and to improve the target properties of material design.

3.
Pak J Pharm Sci ; 36(1): 51-57, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36967496

RESUMO

Angelicin is a furocoumarin found in Psoralea corylifolia L. fruit and the Chinese herb Angelica archangelica. It exerts antitumor activities, including apoptosis, antiproliferation and anti-metastasis activities, in several types of cancers. However, its effects on human triple-negative breast cancer (TNBC) remain unclear. In this study, we evaluated the anticancer activity of angelicin in vitro in the TNBC cell line MDA-MB-231 and investigated the related molecular mechanisms. To determine the anticancer activity of angelicin, MTT assay and flow cytometric analysis were performed to measure the cytotoxicity, cell proliferation and cell cycle. Wound healing assay and trans well assay were used to analyze the migration and invasion of breast cancer cells. The effect of angelicin on the expression of proteins was analyzed by western blotting. The results revealed that angelicin (50, 100, 150µM) had no effect on cytotoxicity. However, angelicin (at 100 µM) could inhibit cell proliferation by reducing cyclin B1 and cdc2 and increasing p21 and p27 expression levels, thereby resulting in G2/M phase arrest. Additionally, angelicin at a concentration of 150 µM inhibited the migration and cell invasion of MDA-MB-231 cells, partially by down regulating MMP-2 protein levels. Together, these results suggest that angelicin may serve as an adjuvant chemotherapeutic agent for patients with TNBC.


Assuntos
Furocumarinas , Neoplasias de Mama Triplo Negativas , Humanos , Apoptose , Ciclo Celular , Divisão Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Furocumarinas/farmacologia , Furocumarinas/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo
4.
J Endovasc Ther ; 28(3): 378-381, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33615881

RESUMO

PURPOSE: Aberrant right subclavian artery (ARSA) associated with Kommerell's diverticulum (KD) is a common congenital arch anomaly. It can be complicated by type B aortic dissection (TBAD) or aneurysmal formation at its ostium. Recently, hybrid repair with thoracic endovascular aortic repair (TEVAR) has appeared to be more favorable. Due to the normal anatomic proximity of the ARSA to the left subclavian artery (LSA) orifice in KD, coverage of the bilateral subclavian arteries (SCAs) to obtain an adequate proximal landing zone (PLZ) is usually required, and double cervicotomy for SCA revascularization potentially increases the risk of complications. TECHNIQUE: This technique was demonstrated on a 50-year-old man presenting with progressive aneurysmal formation of KD with ARSA after chronic TBAD. A 3-step technique, namely left cervical debranching with a left common carotid artery to LSA bypass graft, TEVAR, and an LSA-to-ARSA endovascular debranching with a self-expanding covered stent by a through-and-through wire from the right brachial artery to the bypass graft, was performed in a 1-stage repair to cover the primary tear of TBAD and preserve the bilateral SCAs. The postoperative course was uneventful. CONCLUSION: This technique can prevent complications from double cervicotomy and achieve an adequate PLZ with preservation of the bilateral SCAs for TEVAR.


Assuntos
Dissecção Aórtica , Implante de Prótese Vascular , Divertículo , Procedimentos Endovasculares , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Implante de Prótese Vascular/efeitos adversos , Anormalidades Cardiovasculares , Divertículo/diagnóstico por imagem , Divertículo/cirurgia , Procedimentos Endovasculares/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Subclávia/anormalidades , Artéria Subclávia/diagnóstico por imagem , Artéria Subclávia/cirurgia , Resultado do Tratamento
5.
Artigo em Inglês | MEDLINE | ID: mdl-33032938

RESUMO

OBJECTIVE: Both temporomandibular disorders (TMDs) and sleep bruxism (SB) are known to be destructive to the masticatory system. However, the association between the 2 conditions is poorly understood. The aim of our study was to assess the relationship between TMD and SB through the signs and symptoms in 2 patient groups: TMD only and TMD with SB. STUDY DESIGN: A retrospective chart review was conducted from November 1, 2015, to April 1, 2018, on patients with completed International Network for Orofacial Pain and Related Disorders Methodology history questionnaires and Diagnostic Criteria for Temporomandibular Disorder clinical examinations. Fifty-two patients, including 12 with TMD only and 40 with TMD with SB, met the study criteria. Subjective descriptions and objective measurements of patient symptoms were investigated. The χ2 test and Fisher's exact test were used for statistical analysis. RESULTS: The TMD with SB group exhibited increased oral behaviors compared with the TMD-only group (P = .0004). The TMD with SB group also experienced more headaches compared with the TMD-only group (P = .045). CONCLUSIONS: Our results revealed that patients with jaw pain who self-report increased oral behaviors and/or exhibit temporal headaches should be evaluated for sleep bruxism.


Assuntos
Bruxismo do Sono , Transtornos da Articulação Temporomandibular , Dor Facial/diagnóstico , Dor Facial/etiologia , Humanos , Estudos Retrospectivos , Autorrelato , Bruxismo do Sono/diagnóstico , Transtornos da Articulação Temporomandibular/diagnóstico
6.
Mol Cell Biol ; 39(19)2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31285271

RESUMO

Aminoacyl-tRNA synthetase cofactors play important roles in coordinating aminoacylation and translation. In this study, we describe an additional function of the fission yeast aminoacyl-tRNA synthetase cofactor 1 (Asc1) in translation. We found that Asc1 directly binds and stabilizes the interaction between small ribosomal protein Rps0A/uS2 and eukaryotic initiation factor 3a (eIF3a). In the absence of Asc1, the interaction between eIF3a and Rps0A/uS2 was compromised. The interaction between Rps0A/uS2 and eIF3a mediated the 40S ribosomal subunit binding of eIF3 in 43S preinitiation complex formation to stimulate translation initiation. Keeping with this idea, in an asc1 mutant, the association of mRNA with the 40S ribosomal subunit was defective and protein synthesis was compromised. To show that Asc1 is directly involved in translation, we demonstrate that the addition of recombinant Asc1 is able to rescue the translation defect of the asc1 mutant in a cell-free system. Furthermore, this function of Asc1 is likely to be evolutionarily conserved, as a similar interaction with eIF3a and Rps0A/uS2 could be identified in the budding yeast Saccharomyces cerevisiae and human aminoacyl-tRNA synthetase cofactors. Together, these results identify a function of aminoacyl-tRNA synthetase cofactors in translation preinitiation complex formation, which adds significantly to the expanded functions associated with aminoacyl-tRNA synthetases and their cofactors.


Assuntos
Fator de Iniciação 3 em Eucariotos/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Proteínas Ribossômicas/metabolismo , Schizosaccharomyces/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ligação ao GTP/genética , Humanos , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Biossíntese de Proteínas , RNA Fúngico/genética , RNA Mensageiro/genética , Subunidades Ribossômicas Menores de Eucariotos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo
7.
Sci Rep ; 8(1): 731, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29335649

RESUMO

The purpose of this study was to develop a gellan gum-based multifunctional embolic agent. Calibrated spherical gellan gum and nanoparticle-containing gellan gum microspheres were prepared via water-in oil emulsification method. Self-assembled nanoparticles composed of short-chain hyaluronic acid and polyethylenimine as the doxorubicin carrier were prepared. The short-chain hyaluronic acid/polyethylenimine/ doxorubicin (sHH/PH/Dox) with the mean size was 140 ± 8 nm. To examine sHH/PH/Dox nanoparticle uptake into cells, the results confirmed that sHH/PH nanoparticles as drug carrier can facilitate the transport of doxorubicin into HepG2 liver cancer cells. Subsequently, sHH/PH/Dox merged into the gellan gum (GG) microspheres forming GG/sHH/PH/Dox microsphere. After a drug release experiment lasting 45 days, the amount of released doxorubicin from 285, 388, and 481 µm GG/sHH/PH/Dox microspheres were approximately 4.8, 1.8 and 1.1-fold above the IC50 value of the HepG2 cell. GG/sHH/PH/Dox microspheres were performed in rabbit ear embolization model and ischemic necrosis on ear was visible due to the vascular after 8 days. Regarding the application of this device in the future, we aim to provide better embolization agents for transcatheter arterial chemoembolization (TACE).


Assuntos
Antineoplásicos/farmacologia , Quimioembolização Terapêutica/métodos , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Ácido Hialurônico , Microesferas , Polissacarídeos Bacterianos , Animais , Antineoplásicos/farmacocinética , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacocinética , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Concentração Inibidora 50 , Coelhos
8.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-108200

RESUMO

Low bone mineral density (BMD) and osteoporosis are common in patients with schizophrenia and detrimental to illness prognosis and life quality. Although the pathogenesis is not fully clear, series of studies have revealed factors related to low BMD such as life style, psychotic symptoms, medication use and the activity of bone absorption markers. It has been known that antipsychotic-induced hyperprolactinemia plays a critical role on decreased BMD. However, it remains uncertain whether the risk factors differ between men and women. According to the effect on prolactin, antipsychotics can be classified into two groups: prolactin-sparing (PS) and prolactin-raising (PR). Our previous study has demonstrated that clozapine which is among the PS antipsychotics is beneficial for BMD when compared with PR antipsychotics in women with chronic schizophrenia. We have also found that risks factors associated with low BMD are different between men and women, suggesting that gender-specific risk factors should be considered for intervention of bone loss in patients with schizophrenia. This article reviews the effects of antipsychotics use on BMD with particular discussion for the differences on gender and age, which implicate the alterations of sex and other related hormones. In addition, currently reported protective and risk factors, as well as the effects of medication use on BMD including the combination of antipsychotics and other psychotropic agents and other potential medications are also reviewed.


Assuntos
Feminino , Humanos , Masculino , Absorção , Antipsicóticos , Densidade Óssea , Clozapina , Hiperprolactinemia , Estilo de Vida , Osteoporose , Prognóstico , Prolactina , Qualidade de Vida , Fatores de Risco , Esquizofrenia
9.
Mol Cell Biol ; 26(23): 8953-63, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17000765

RESUMO

Ral GTPase activity is a crucial cell-autonomous factor supporting tumor initiation and progression. To decipher pathways impacted by Ral, we have generated null and hypomorph alleles of the Drosophila melanogaster Ral gene. Ral null animals were not viable. Reduced Ral expression in cells of the sensory organ lineage had no effect on cell division but led to postmitotic cell-specific apoptosis. Genetic epistasis and immunofluorescence in differentiating sensory organs suggested that Ral activity suppresses c-Jun N-terminal kinase (JNK) activation and induces p38 mitogen-activated protein (MAP) kinase activation. HPK1/GCK-like kinase (HGK), a MAP kinase kinase kinase kinase that can drive JNK activation, was found as an exocyst-associated protein in vivo. The exocyst is a Ral effector, and the epistasis between mutants of Ral and of msn, the fly ortholog of HGK, suggest the functional relevance of an exocyst/HGK interaction. Genetic analysis also showed that the exocyst is required for the execution of Ral function in apoptosis. We conclude that in Drosophila Ral counters apoptotic programs to support cell fate determination by acting as a negative regulator of JNK activity and a positive activator of p38 MAP kinase. We propose that the exocyst complex is Ral executioner in the JNK pathway and that a cascade from Ral to the exocyst to HGK would be a molecular basis of Ral action on JNK.


Assuntos
Apoptose , Drosophila melanogaster/citologia , Drosophila melanogaster/embriologia , Proteínas de Ligação ao GTP/metabolismo , Proteína Quinase 9 Ativada por Mitógeno/metabolismo , Alelos , Animais , Diferenciação Celular , Linhagem da Célula , Drosophila melanogaster/enzimologia , Drosophila melanogaster/genética , Embrião não Mamífero , Ativação Enzimática , Epistasia Genética , Proteínas de Ligação ao GTP/genética , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Genes Essenciais , Genes de Insetos , Imuno-Histoquímica , MAP Quinase Quinase 4/metabolismo , Microscopia de Vídeo , Proteínas Serina-Treonina Quinases/metabolismo , Órgãos dos Sentidos/embriologia , Órgãos dos Sentidos/crescimento & desenvolvimento , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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