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1.
Int J Mol Sci ; 24(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36614203

RESUMO

Little is known about alternative treatment options for rhinosinusitis (RS). We aimed to evaluate the efficacy of low-level laser therapy (LLLT) for RS in experimentally induced rabbit models of RS. A total of 18 rabbits were divided into four groups: a negative control group (n = 3), an RS group without treatment (n = 5, positive control group), an RS group with natural recovery (n = 5, natural recovery group), and an RS group with laser irradiation (n = 5, laser-treated group). Computed tomography and histopathological staining were performed for each group. mRNA and protein expression levels of local cytokines (IFN-γ, IL-17, and IL-5) were also measured. Tissue inflammation revealed a significant improvement in the laser-treated group compared with the RS and natural recovery groups (p < 0.01). In addition, sinus opacification in the CT scans and cytokine expression was reduced in the laser-treated group, though without statistical significance. LLLT could be an effective option for the management of RS concerning radiological, histological, and molecular parameters.


Assuntos
Terapia com Luz de Baixa Intensidade , Rinite , Sinusite , Animais , Coelhos , Citocinas/genética , Citocinas/metabolismo , Terapia com Luz de Baixa Intensidade/métodos , Sinusite/metabolismo , Sinusite/terapia , Rinite/metabolismo , Rinite/terapia
2.
Materials (Basel) ; 15(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36431448

RESUMO

The wind tower block is welded with the flange to assemble the wind tower. The inherent strain due to local heating and cooling of the weld affects the flatness of the flange. Therefore, line heating is performed to satisfy the design criteria of the flange flatness, but the work variables depend on the operator's empirical judgment. This study proposed a method to determine the optimum linear heating conditions to control the welded flatness of wind tower blocks and flanges. A proposed method uses the inherent strain method, a simple analysis method, and the optimization is performed based on the deformation superposition method. The changes in flange flatness due to welding and single-point heating were calculated. Then, the flatness change due to single-point heating is superimposed with a scale factor, which represents the magnitude of line heating, and is added to the flatness change due to welding. Using the optimization procedure, the line heating conditions used to derive the flatness that satisfies the design criteria were derived and applied to the analytical model for verification.

3.
Immune Netw ; 22(4): e35, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36081523

RESUMO

Tobacco smoking (TS) has been known as one of the most potent risk factors for airway inflammatory diseases. However, there has been a paucity of information regarding the immunologic alteration mediated by TS in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). To identify the effect of TS, we harvested human tissue samples (never smoker: n=41, current smoker: n=22, quitter: n=23) and analyzed the expression of epithelial-derived cytokines (EDCs) such as IL-25, IL-33, and thymic stromal lymphopoietin. The expressions of Th2 cytokines and total serum IgE showed a type-2 inflammatory alteration by TS. In addition, the epithelial marker E-cadherin and epithelial-mesenchymal transition (EMT)-associated markers (N-cadherin, α-SMA, and vimentin) were evaluated. Histological analysis showed that EDC expressions were upregulated in the current smoker group and downregulated in the quitter group. These expression patterns were consistent with mRNA and protein expression levels. We also found that the local Th2 cytokine expression and IgE class switching, as well as serum IgE levels, were elevated in the current smoker group and showed normal levels in the quitter group. Furthermore, the expressions of E-cadherin decreased while those of N-cadherin, α-SMA, and vimentin increased in the current smoker group compared those in the never smoker group. Taken together, these results indicate that TS contributes to the deterioration of pathogenesis by releasing local EDCs and Th2 cytokines, resulting in EMT in patients with CRSwNP. We verified that alterations of immunological response by TS in sinonasal epithelium can play a vital role in leading to CRSwNP.

4.
Materials (Basel) ; 15(1)2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35009262

RESUMO

In the shipbuilding industry, welding is the main technique used to join steel structures. There is a lifting process, post-welding, that can eliminate the correction effect of line heating. Line heating is reperformed after the lifting process. This can significantly delay the ship assembly process. Herein, we present a design method for installing a permanent stiffener to avoid the disappearance of the line heating effect during the lifting process. The change in physical properties due to heating and cooling of the line heating is calculated. The limiting stress, at which the effect of the line heating completely disappears, based on the inherent strain theory, is obtained. The phase fraction by the cooling rate is calculated using the continuous cooling transformation diagram and the Kiustinen-Marburgerm equation. Physical properties affected by the phase transformation are calculated, considering the physical properties and fraction of each phase. The square plate theory and superposition principle are used to construct a local model, with a stiffener, of the ship block. The stress caused by the shape of the stiffener and the distance between the stiffeners were calculated for the local model. The calculated stress and the limiting stress were compared to determine, for the expected line heating efficiency, the most acceptable stiffener design. Finally, to confirm the elimination of the problem, the designed stiffener is analyzed using the finite element method.

5.
Mol Biol Rep ; 46(4): 4225-4234, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31102152

RESUMO

Sirt1, also known as the longevity gene, is an NAD+-dependent class III histone deacetylase that has been extensively studied in multiple areas of research including cellular metabolism, longevity, cancer, autoimmunity, and immunity. However, little is known about the function of Sirt1 in B cells. This study aimed to investigate the role of Sirt1 in the expression pattern of mRNAs in the resting B cells of mice. CD19+ B cell-specific inducible Sirt1 knockout (KO) mice were divided into tamoxifen-treated Sirt1 KO group (S19T) or control group (S19). mRNAs extracted from resting B cells of both groups were analyzed for differentially expressed genes (DEG) using microarray. DEG analysis showed significant differential expression of 20 genes, of which Hspa1a and Hspa1b showed the highest fold change (FC) in S19T compared with S19 (p value < 0.01 and FC > 3). Further, Kyoto Encyclopedia of Genes and Genomes analysis identified pathways associated with diseases, organismal systems, and antigen processing and presentation. Additionally, the pathways known to involve Hspa1a and Hspa1b were also activated in the S19T group. On the other hand, after in vitro stimulation with lipopolysaccharide, cell viability and IgM production were significantly decreased in Sirt1 KO B cells, while expressions of TNF-α, IL-6, and IL-10 were increased. In summary, our study reveals that Sirt1 may maintain the quiescent state in resting B cells by suppressing the increase of Hspa1a and Hspa1b. This work provides a foundation for further studies on the functional roles of Sirt1 in B cells.


Assuntos
Linfócitos B/metabolismo , Proteínas de Choque Térmico HSP70/genética , Sirtuína 1/deficiência , Animais , Linfócitos B/fisiologia , Sobrevivência Celular , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo
6.
J Environ Sci (China) ; 67: 198-205, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29778153

RESUMO

The toxic effects of the composites of Fe0 and Cu0 with different percentages of CNTs were examined based on the activity of bacterial bioluminescence and seed germination. In terms of the EC50 values, the toxic effects of Cu0 on bacterial bioluminescence and seed germination were approximately 2 and 180 times greater than that of Fe0, respectively. The toxicity increased with increasing CNT content in the Cu-CNT mixtures for both organisms, whereas opposite results were observed with Fe-CNT mixtures. The mean toxic effects of Cu-CNT (6%) were approximately 1.3-1.4 times greater than that of Cu-CNT (0%), whereas the toxic effects of Fe-CNT (6%) were approximately 2.1-2.5 times lower than that of Fe-CNT (0%) for both the bioluminescence activity and seed germination. The causes of this phenomenon are unclear at this point. More research will be needed to elucidate the mechanism of the toxicity of nano-mixture materials and the causes of the different patterns of toxicity with Cu- and Fe-CNT mixtures.


Assuntos
Complexos de Coordenação/toxicidade , Cobre/toxicidade , Poluentes Ambientais/toxicidade , Germinação/efeitos dos fármacos , Nanotubos de Carbono/toxicidade , Ferro/toxicidade , Luminescência , Testes de Toxicidade
7.
J Mech Behav Biomed Mater ; 61: 122-134, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26854935

RESUMO

Graphene nanoplatelets were added as reinforcement to alumina ceramics in order to enhance microscale tribological behavior, which would be beneficial for ceramic-on-ceramic hip implant applications. The reduction in microscale wear is critical to hip implant applications where small amounts of wear debris can be detrimental to patients and to implant performance. The addition of the GNPs lead to improvements in fracture toughness and wear (scratch) resistance of 21% and 39%, respectively. The improved wear resistance was attributed to GNP-induced toughening, which generates fine (~100nm) microcracks on the scratch surface. In addition, active participation of GNPs was observed in the scratch subsurface of GNP-reinforced samples through focused ion beam sectioning. Friction coefficients are not significantly influenced by the addition of GNPs, and hence GNPs do not act as solid state lubricants. In vitro biocompatibility with human osteoblasts was assessed to evaluate any possible cytotoxic effects induced by GNPs. Osteoblast cells were observed to survive and proliferate robustly in the GNP-reinforced samples, particularly those with high (10-15vol%) GNP content.


Assuntos
Óxido de Alumínio/química , Materiais Biocompatíveis/química , Cerâmica/química , Grafite/química , Nanopartículas/química , Células Cultivadas , Prótese de Quadril , Humanos , Osteoblastos/citologia
8.
Biomed Res Int ; 2014: 768254, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24724100

RESUMO

Pure HA and 1, 3, 5, and 10 vol% multiwalled carbon nanotube- (MWNT-) reinforced hydroxyapatite (HA) were consolidated using a spark plasma sintering (SPS) technique. The relative density of pure HA increased with increasing sintering temperature, but that of the MWNT/HA composite reached almost full density at 900°C, and then decreased with further increases in sintering temperature. The relative density of the MWNT/HA composites increased with increasing MWNT content due to the excellent thermal conductivity of MWNTs. The grain size of MWNT/HA composites decreased with increasing MWNT content and increased with increasing sintering temperature. Pull-out toughening of the MWNTs of the MWNT/HA composites was observed in the fractured surface, which can be used to predict the improvement of the mechanical properties. On the other hand, the existence of undispersed or agglomerate MWNTs in the MWNT/HA composites accompanied large pores. The formation of large pores increased with increasing sintering temperature and MWNT content. The addition of MWNT in HA increased the hardness and fracture toughness by approximately 3~4 times, despite the presence of large pores produced by un-dispersed MWNTs. This provides strong evidence as to why the MWNTs are good candidates as reinforcements for strengthening the ceramic matrix. The MWNT/HA composites did not decompose during SPS sintering. The MWNT-reinforced HA composites were non-toxic and showed a good cell affinity and morphology in vitro for 1 day.


Assuntos
Durapatita/química , Teste de Materiais , Nanocompostos/química , Nanotubos de Carbono/química , Osteoblastos/metabolismo , Animais , Linhagem Celular , Camundongos , Osteoblastos/citologia , Porosidade
9.
Toxicol Res ; 30(4): 305-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25584151

RESUMO

Recently, there has been an increase in the use of several nephrotoxicity biomarkers in preclinical experiments. In addition, it has been indicated that the result may have been influenced by secondary factors, such as sample storage condition or storage period. In this study, we have assessed the variation in urinary nephrotoxicity biomarkers as a result of urine storage conditions and storage period of the urine. Urine was sampled from specific pathogen-free Sprague-Dawley rats (19 weeks old), which were housed individually in hanged stainless steel wire mesh cages. Urine was stored at 20℃, at 4℃, or at -70℃ after sampling. The levels of the biomarkers such as beta-2 microglobulin (B2M), cystatin-C (Cys-C), N-acetyl-ß- D-glucosaminidase (NAG), micro albumin (MA), micro protein (MP) were measured at 6, 24, 48 and 144 hr after sampling. The B2M level was significantly decreased at 6, 24, 48, and 144 hr compared to 0 hr at -70℃ (p < 0.05, p < 0.01, p < 0.05, and p < 0.05, respectively) and 24 and 144 hr at 20℃ (p < 0.01, p < 0.01, respectively). The Cys-C level was significantly decreased at 144 hr compared to 0 hr at 4℃ (p < 0.01), at 20℃ (p < 0.05) and at 70℃ (p < 0.01). MP and MA levels were not different for 144 hr in all storage conditions. Taken together, B2M and Cys-C levels were modulated by storage temperature and period. For the enhancement of test accuracy, it is suggested that strict protocols be established for samples to minimize the effects of the storage conditions on the detected levels of biomarkers.

10.
Nanotechnology ; 21(7): 75302, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20081291

RESUMO

The one-pot fabrication of various silver nanostructures on substrates is achieved through electron beam irradiation of the surface of silver dodecanethiolate (Ag(I)- SC(12)). The Ag(I)-SC(12) films are simply prepared by spin-coating silver salt and dodecanethiol solution. Various silver nanostructures such as particles, rods, cubes, and networks are prepared from the Ag(I)- SC(12) film with an electron beam voltage from 0.3 to 2 MV, current from 0.06 to 0.24 mA, and/or irradiation time from 30 to 80 s. The morphology and chemical composition of the irradiated samples are characterized by scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), and x-ray diffraction (XRD).


Assuntos
Elétrons , Nanoestruturas/química , Nanotecnologia/métodos , Prata/química , Espectroscopia Fotoeletrônica , Compostos de Sulfidrila
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