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2.
Mol Pharm ; 21(3): 1300-1308, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38294949

RESUMO

Keratin and lipid structures in the stratum corneum (SC) are closely related to the SC barrier function. The application of penetration enhancers (PEs) disrupts the structure of SC, thereby promoting infiltration. To quantify these PE-induced structural changes in SC, we used confocal Raman imaging (CRI) and polarized Raman imaging (PRI) to explore the integrity and continuity of keratin and lipid structures in SC. The results showed that water is the safest PE and that oleic acid (OA), sodium dodecyl sulfate (SDS), and low molecular weight protamine (LMWP) disrupted the ordered structure of keratin, while azone and liposomes had less of an effect on keratin. Azone, OA, and SDS also led to significant changes in lipid structure, while LMWP and liposomes had less of an effect. Establishing this non-invasive and efficient strategy will provide new insights into transdermal drug delivery and skin health management.


Assuntos
Lipossomos , Pele , Lipossomos/farmacologia , Epiderme , Ácido Oleico/farmacologia , Queratinas
3.
Int J Mol Sci ; 23(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35216331

RESUMO

A highly efficient Agrobacterium-mediated transformation method is needed for the molecular study of model tree species such as hybrid poplar 84K (Populus alba × P. glandulosa cv. '84K'). In this study, we report a callus-based transformation method that exhibits high efficiency and reproducibility. The optimized callus induction medium (CIM1) induced the development of calli from leaves with high efficiency, and multiple shoots were induced from calli growing on the optimized shoot induction medium (SIM1). Factors affecting the transformation frequency of calli were optimized as follows: Agrobacterium concentration sets at an OD600 of 0.6, Agrobacterium infective suspension with an acetosyringone (AS) concentration of 100 µM, infection time of 15 min, cocultivation duration of 2 days and precultivation duration of 6 days. Using this method, transgenic plants are obtained within approximately 2 months with a transformation frequency greater than 50%. Polymerase chain reaction (PCR), reverse transcription-PCR (RT-PCR) and ß-galactosidase (GUS) histochemical staining analyses confirmed the successful generation of stable transformants. Additionally, the calli from leaves were subcultured and used to obtain new explants; the high transformation efficiency was still maintained in subcultured calli after 6 cycles. This method provides a reference for developing effective transformation protocols for other poplar species.


Assuntos
Acetofenonas/metabolismo , Populus/genética , Transformação Genética/genética , Agrobacterium tumefaciens/genética , Vetores Genéticos/genética , Folhas de Planta/genética , Plantas Geneticamente Modificadas/genética , Reprodutibilidade dos Testes
4.
Biotechnol Bioeng ; 118(1): 153-163, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32897579

RESUMO

Escherichia coli BL21 (DE3) is an excellent and widely used host for recombinant protein production. Many variant hosts were developed from BL21 (DE3), but improving the expression of specific proteins remains a major challenge in biotechnology. In this study, we found that when BL21 (DE3) overexpressed glucose dehydrogenase (GDH), a significant industrial enzyme, severe cell autolysis was induced. Subsequently, we observed this phenomenon in the expression of 10 other recombinant proteins. This precludes a further increase of the produced enzyme activity by extending the fermentation time, which is not conducive to the reduction of industrial enzyme production costs. Analysis of membrane structure and messenger RNA expression analysis showed that cells could underwent a form of programmed cell death (PCD) during the autolysis period. However, blocking three known PCD pathways in BL21 (DE3) did not completely alleviate autolysis completely. Consequently, we attempted to develop a strong expression host resistant to autolysis by controlling the speed of recombinant protein expression. To find a more suitable protein expression rate, the high- and low-strength promoter lacUV5 and lac were shuffled and recombined to yield the promoter variants lacUV5-1A and lac-1G. The results showed that only one base in lac promoter needs to be changed, and the A at the +1 position was changed to a G, resulting in the improved host BL21 (DE3-lac1G), which resistant to autolysis. As a consequence, the GDH activity at 43 h was greatly increased from 37.5 to 452.0 U/ml. In scale-up fermentation, the new host was able to produce the model enzyme with a high rate of 89.55 U/ml/h at 43 h, compared to only 3 U/ml/h achieved using BL21 (DE3). Importantly, BL21 (DE3-lac1G) also successfully improved the production of 10 other enzymes. The engineered E. coli strain constructed in this study conveniently optimizes recombinant protein overexpression by suppressing cell autolysis, and shows great potential for industrial applications.


Assuntos
RNA Polimerases Dirigidas por DNA/biossíntese , Regulação para Baixo , Escherichia coli , Expressão Gênica , Vetores Genéticos , Regiões Promotoras Genéticas , Proteínas Virais/biossíntese , RNA Polimerases Dirigidas por DNA/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Virais/genética
5.
Kaohsiung J Med Sci ; 37(2): 121-127, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33022894

RESUMO

Cullin 4B (CUL4B) was reported to be closely related to the progression of some tumors, but its function in clear cell renal cell carcinoma (ccRCC) has not been reported. Our present study found CUL4B was upregulated in ccRCC, and CUL4B knockdown markedly inhibited ccRCC cell growth and induced apoptosis. In addition, CUL4B knockdown markedly inhibited antiapoptotic proteins' expression in ccRCC cells, including Mcl-1 and Bcl-2, and silenced CUL4B also induced the cleavages of PARP, an important index of apoptosis. We also confirmed microRNA-217 (miR-217) was downregulated in ccRCC tumor tissues, and negatively correlated with CUL4B expression. Further investigations revealed miR-217 targeted CUL4B and markedly inhibited its expression in ccRCC cells. In addition, overexpression of miR-217 by mimics significantly suppressed ccRCC cell growth. In contrast, enforced expression of CUL4B significantly abolished miR-217-induced cell survival inhibition in ccRCC cells. In conclusion, our present results suggested targeting miR-217-CUL4B axis would be a promising strategy for ccRCC treatment.


Assuntos
Apoptose , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Proteínas Culina/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/patologia , MicroRNAs/metabolismo , Apoptose/genética , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/genética , Sobrevivência Celular/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , MicroRNAs/genética
6.
Ying Yong Sheng Tai Xue Bao ; 30(12): 4293-4302, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31840476

RESUMO

Bay cities have abundant land-sea resources and higher environmental carrying capacity. The high density of population and industry surrounding the bay makes bay cities a type of ecologically fragile areas. With Quanzhou, a typical bay city, as an example, we simulated the land use and landscape pattern change in 2030 based on multiple data sources (land use data, meteorological site data, topographic data and statistical data) using Logistic-CA-Markov coupling model to set natural scenarios, planning scenarios and protection scenarios. Four key ecosystem service (ES) including water retention, soil conservation, carbon sequestration (NPP), food supply and their trade-offs were calculated and predicted. Under the three scenarios, the area of cultivated land and construction land in Quanzhou City would increase in 2030. Forest land, grassland and water area would be reduced in varying degrees. The fragmentation of land use would be serious. In comparison with 2015, except for soil conservation service, water retention, carbon sequestrtion and food supply of Quanzhou City would decline to varying degrees in 2030. Ecosystem service function in natural scenario would be more decreased, with the decline under the protection scenario being lower than the planning scenario. In the protection and planning scenarios, the synergy between water conservation and soil conservation, water conservation and carbon sequestrtion, soil conservation and carbon sequestrtion in 2030 would be enhanced and the trade-offs would be weakened.


Assuntos
Baías , Ecossistema , China , Cidades , Conservação dos Recursos Naturais
7.
Ann Vasc Surg ; 61: 203-211, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31381999

RESUMO

BACKGROUND: Willis covered stents are used in clinical practice for some complex cerebrovascular diseases. However, the performance of the Willis covered stent requires further investigation. In this study, we investigate the safety and efficacy of Willis covered stents for the treatment of complex vascular diseases of the internal carotid artery (ICA). METHODS: Thirteen patients with complex ICA diseases treated with the Willis covered stent system at our institution from October 2016 to January 2018 were analyzed retrospectively. Follow-up observation and digital subtraction angiography (DSA) examination were conducted at about 6-10 months after the treatment. RESULTS: The complex vascular diseases of the ICA were successfully treated in 12 patients. The technical success rate was 92.3%. Pathologically, 13 lesions included blood blister-like aneurysm (n = 7), traumatic pseudoaneurysm (n = 1), traumatic carotid artery rupture (n = 1), and aneurysm with arteriovenous fistula (n = 4). Thirteen patients with complex vascular diseases of the ICA were treated with 15 Willis covered stents. The release sites of Willis covered stents were the C7 (n = 2), C6 (n = 1), C5 and/or C4 (n = 9), and the C2 (n = 3) segment of the ICA. DSA performed immediately after stent deployment revealed that complete occlusion of the lesion was achieved in 11 patients and endoleak was observed in 2 patients. Of the 11 patients, postoperative DSA examination indicated that the lesions were occluded completely. Among 2 patients, who had a second stent implantation at the break of the ICA, the traumatic ICA rupture was essentially completely obstructed in 1 patient. The endoleak remained in 1 patient with carotid cavernous sinus fistula because the placement of the second stent system was difficult with his ICA tortuosity. No recurrence of aneurysms, hemorrhagia, and other lesions was observed, and the patients' parent arteries were patent without stenosis. No procedure-related complications or deaths occurred during follow-up. CONCLUSIONS: For the treatment of complex vascular diseases in the ICA, Willis covered stent implantation is safe and effective. However, longer follow-up, large-sample controlled studies, and multicenter studies are needed for further confirmation.


Assuntos
Doenças das Artérias Carótidas/terapia , Artéria Carótida Interna/fisiopatologia , Circulação Cerebrovascular , Círculo Arterial do Cérebro/fisiopatologia , Procedimentos Endovasculares/instrumentação , Stents , Adolescente , Adulto , Angiografia Digital , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/fisiopatologia , Artéria Carótida Interna/diagnóstico por imagem , Círculo Arterial do Cérebro/diagnóstico por imagem , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
8.
J Cell Biochem ; 119(1): 1008-1016, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28686347

RESUMO

There was no effective measures can be obtained at present to reverse or prevent airway remodeling. We investigated the therapeutic effect of Erythropoietin (EPO) gene modified mesenchymal stem cells (MSCs) on asthmatic airway remodeling and the possible underlied molecular mechanisms. EPO gene was transfected into MSCs via lentivirus vector. The transfected cells (EPO-MSCs) were identified by flow cytometry and the EPO secreting function was detected by PCR and Western blot. MSCs or EPO-MSCs were administrated to albumin (OVA)-induced chronic asthmatic mouse model via tail veins. The asthmatic phenotype was analyzed. Number of cells in bronchoalveolar lavage fluid (BALF) was counted using a hemocytometer. Histological findings of airways were evaluated by microscopic examination. The concentrations of interleukin 4(IL-4), interleukin 5(IL-5), and interleukin 13(IL-13) in lung homogenate were determined by ELISA. The activation state of transforming growth factor-ß 1 (TGF-ß1), Transforming growth factor beta-activated kinase 1 (TAK1), and p38 Mitogen Activated Protein Kinase (p38MAPK) signaling was detected by Real-Time PCR and Western blotting. EPO-MSCs were successfully constructed. EPO-MSCs showed a more potently suppressive effect on local asthmatic airway inflammation and the level of IL-4, IL-5, and IL-13 in lung tissue than MSCs. Moreover, the numbers of goblet cells, the thicknesses of smooth muscle layer, collagen density, percentage of proliferating cell nuclear antigen positive (PCNA+ ) mesenchymal cells, and von Willebrand factor positive(vWF+ ) vessels were also significantly inhibited by EPO-MSCs. Furthermore, EPO-MSCs could downregulate the expression of TGF-ß1, TAK1, and p38MAPK in lung tissue both in mRNA level and in protein level. EPO gene modified MSCs may more efficiently attenuate asthmatic airway remodeling, which maybe related with the downregulation of TGF-ß1-TAK1-p38MAPK pathway activity.


Assuntos
Remodelação das Vias Aéreas/efeitos dos fármacos , Asma/terapia , Modelos Animais de Doenças , Eritropoetina/farmacologia , Células-Tronco Mesenquimais/citologia , Animais , Asma/genética , Asma/metabolismo , Asma/patologia , Líquido da Lavagem Broncoalveolar/citologia , Eritropoetina/genética , Regulação da Expressão Gênica , Terapia Genética , Interleucinas/metabolismo , Lentivirus/genética , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C
9.
Sci Rep ; 7(1): 9048, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28831069

RESUMO

With the rapid growth of micro-organism metabolic networks, acquiring the intracellular concentration of microorganisms' metabolites accurately in large-batch is critical to the development of metabolic engineering and synthetic biology. Complementary to the experimental methods, computational methods were used as effective assessing tools for the studies of intracellular concentrations of metabolites. In this study, the dataset of 130 metabolites from E. coli and S. cerevisiae with available experimental concentrations were utilized to develop a SVM model of the negative logarithm of the concentration (-logC). In this statistic model, in addition to common descriptors of molecular properties, two special types of descriptors including metabolic network topologic descriptors and metabolic pathway descriptors were included. All 1997 descriptors were finally reduced into 14 by variable selections including genetic algorithm (GA). The model was evaluated through internal validations by 10-fold and leave-one-out (LOO) cross-validation, as well as external validations by predicting -logC values of the test set. The developed SVM model is robust and has a strong predictive potential (n = 91, m = 14, R2 = 0.744, RMSE = 0.730, Q2 = 0.57; R2p = 0.59, RMSEp = 0.702, Q2p = 0.58). An effective tool could be provided by this analysis for the large-batch prediction of the intracellular concentrations of the micro-organisms' metabolites.


Assuntos
Metabolismo Energético , Espaço Intracelular/microbiologia , Microbiologia , Modelos Teóricos , Escherichia coli/fisiologia , Redes e Vias Metabólicas , Saccharomyces cerevisiae/fisiologia
10.
Int Immunopharmacol ; 46: 133-140, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28282577

RESUMO

Repeated airway inflammation and unremitting remodeling provoke irreversible pulmonary dysfunction and resistance to current drugs in patients with chronic bronchial asthma. Interleukin (IL)-13 and IL-25 play an important role in airway inflammation and remodeling in asthma. We aimed to investigate whether co-inhibiting IL-13 and IL-25 can effectively down-regulate allergen-induced airway inflammation and remodeling in mice. Mice with asthma induced by chronic exposure to ovalbumin (OVA) were given soluble IL-13 receptor α2 (sIL-13R) or soluble IL-25 receptor (sIL-25R) protein alone and in combination to neutralize the bioactivity of IL-13 and IL-25, and relevant airway inflammation and remodeling experiments were performed. We found that the co-blockade of IL-13 and IL-25 with sIL-13R and sIL-25R was more effective than either agent alone at decreasing inflammatory cell infiltration, airway hyperresponsiveness (AhR) and airway remodeling including mucus production, extracellular collagen deposition, smooth muscle cell hyperplasia and angiogenesis in mice exposed to OVA. These results suggest that the combined inhibition of IL-13 and IL-25 may provide a novel therapeutic strategy for asthma, especially for patients who are resistant to current treatments.


Assuntos
Asma/terapia , Imunoterapia/métodos , Interleucina-13/metabolismo , Interleucinas/metabolismo , Pulmão/efeitos dos fármacos , Receptores de Interleucina-13/uso terapêutico , Receptores de Interleucina/uso terapêutico , Remodelação das Vias Aéreas/efeitos dos fármacos , Alérgenos/imunologia , Animais , Asma/imunologia , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Humanos , Imunoglobulina E/sangue , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia
11.
Epilepsy Res ; 128: 35-42, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27810514

RESUMO

Post-traumatic epilepsy (PTE) is one of the most common complications resulting from brain injury, however, antiepileptic drugs usually fail to prevent it. Several lines of evidence have demonstrated that the endogenous cannabinoid system (ECS) plays a pivotal role during epileptogenesis in several animal models. A recent study has shown that a cannabinoid type 1 (CB1) receptor antagonist could suppress long-term neuron hyperexcitability after brain injury, but the underlying mechanisms remain largely unknown. In this study, we first analyzed the dynamic expression of different components of the ECS at various time points after brain injury in rats. Then, we conducted a 12-month-long session of behavioral monitoring after the brain injury, and based on the results, the rats were divided into a PTE group and a non-PTE group. Finally, the changes in the ECS between the two groups were compared. We found that the ECS exhibited a biphasic alteration after brain injury; the expression of the CB1 receptor and 2-arachidonoylglycerol (2-AG) in the PTE group was significantly higher than that of the non-PTE group 12 months after traumatic brain injury. Our preliminary results indicated that the ECS might be involved in post-traumatic epileptogenesis.


Assuntos
Lesões Encefálicas/complicações , Lesões Encefálicas/metabolismo , Endocanabinoides/metabolismo , Epilepsia Pós-Traumática/metabolismo , Animais , Ácidos Araquidônicos/metabolismo , Western Blotting , Modelos Animais de Doenças , Progressão da Doença , Eletrocorticografia , Epilepsia Pós-Traumática/etiologia , Expressão Gênica/fisiologia , Glicerídeos/metabolismo , Hipocampo/metabolismo , Masculino , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Receptor CB1 de Canabinoide/metabolismo
12.
Planta ; 244(2): 417-27, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27084679

RESUMO

MAIN CONCLUSION: The PeNAC1 promoter is a non-tissue-specific and stress-inducible promoter containing a GA-responsive element and a MYB recognition sequence that are responsible for induced expression patterns. NAC transcription factors play vital roles in complex signaling networks during plant stress responses. Promoters as crucial molecular switches are involved in the transcriptional regulation of gene activities dynamic network controlling a variety of biological processes, such as developmental processes, responses to hormone and abiotic stress. In this study, a 1217-bp flanking fragment of the stress-responsive NAC gene PeNAC1 was isolated from Populus euphratica. In transgenic Arabidopsis, this promoter fragment was found to have a higher activity than the cauliflower mosaic virus 35S promoter and remained active throughout the plant life cycle, particularly in the spiral vessels and cortical cells of vascular tissues of various organs. We identified a gibberellic acid-responsive element, required for response to gibberellic acid and involved in the salt-stress signaling pathway, and a MYB recognition sequence, which has an important role in promoter response to drought stress, in the PeNAC1 promoter. These results suggest that the PeNAC1 promoter is more effective, non-tissue-specific, and inducible. In addition, the presence of a putative NAC protein-binding motif in the PeNAC1 promoter indicates that PeNAC1 is either regulated by other NAC transcription factors or is self-regulated. Our research will help reveal the regulatory mechanism of the upstream region of the PeNAC1 gene and provide a foundation for the use of the PeNAC1 promoter in molecular breeding.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Populus/genética , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Arabidopsis/genética , Giberelinas/farmacologia , Plantas Geneticamente Modificadas/metabolismo , Análise de Sequência de DNA , Estresse Fisiológico/genética , beta-Galactosidase/análise
14.
Int J Clin Exp Pathol ; 8(11): 14171-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26823730

RESUMO

The typical pathological features of asthma are airway remodeling and airway hyperresponsiveness (AHR). KyoT2, a negative modulator of Notch signaling, has been linked to asthma in several previous studies. However, whether KyoT2 is involved in the regulation of airway remodeling or the modulation of airway resistance in asthma is unclear. In this study, we aimed to evaluate the therapeutic potential of KyoT2 in preventing asthma-associated airway remodeling and AHR. BALB/c mice were used to generate a mouse model of asthma. Additionally, the expression of Hes1 and Notch1 in airway was analyzed using Immunofluorescence examination. The asthmatic mice were intranasally administered adenovirus expressing KyoT2 and were compared to control groups. Furthermore, subepithelial fibrosis and other airway remodeling features were analyzed using hematoxylin and eosin staining, Van Gieson's staining and Masson's trichrome staining. AHR was also evaluated. This study revealed that KyoT2 downregulated the expression of Hes1, repressed airway remodeling, and alleviated AHR in asthmatic mice. It is reasonable to assume that KyoT2 downregulates airway remodeling and resistance in asthmatic mice through a Hes1-dependent mechanism. Therefore, KyoT2 is a potential clinical treatment strategy for asthma.


Assuntos
Remodelação das Vias Aéreas , Asma/terapia , Hiper-Reatividade Brônquica/terapia , Terapia Genética/métodos , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Proteínas com Domínio LIM/biossíntese , Pulmão/metabolismo , Proteínas Musculares/biossíntese , Adenoviridae/genética , Adenoviridae/metabolismo , Resistência das Vias Respiratórias , Animais , Asma/genética , Asma/metabolismo , Asma/patologia , Asma/fisiopatologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Hiper-Reatividade Brônquica/genética , Hiper-Reatividade Brônquica/metabolismo , Hiper-Reatividade Brônquica/patologia , Hiper-Reatividade Brônquica/fisiopatologia , Modelos Animais de Doenças , Fibrose , Técnicas de Transferência de Genes , Vetores Genéticos , Proteínas de Homeodomínio/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas com Domínio LIM/genética , Pulmão/patologia , Pulmão/fisiopatologia , Masculino , Camundongos Endogâmicos BALB C , Proteínas Musculares/genética , Receptor Notch1/metabolismo , Transdução de Sinais , Fatores de Transcrição HES-1
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(9): 2424-8, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25532338

RESUMO

Pearl is a precious ornament and traditional Chinese medicine, which application history in China is more than 2000 years. It is well known that the chemical ingredients of shell and pearl are very similar, which all of them including calcium carbonate and various amino acids. Generally, shell powders also can be used as medicine; however, its medicinal value is much lower than that of pearl powders. Due to the feature similarity between pearl powders and shell powders, the distinguishment of them by detecting chemical composition and morphology is very difficult. It should be noted that shell powders have been often posing as pearl powders in markets, which seriously infringes the interests of consumers. Identification of pearl powder was investigated by microscopic infrared reflectance spectroscopy, and pearl powder as well as shell powder was calcined at different temperatures for different time before infrared reflectance spectroscopy analysis. The experimental results indicated that when calcined at 400 °C for 30 minutes under atmospheric pressure, aragonite in pearl powder partly transformed into calcite, while aragonite in shell powder completely transformed into calcite. At the same time, the difference in phase transition between the pearl powders 'and shell powders can be easily detected by using the microscopic infrared reflectance spectroscopy. Therefore, based on the difference in their phase transition process, infrared reflectance spectroscopy can be used to identify phase transformation differences between pearl powder and shell powder. It's more meaningfully that the proposed infrared reflectance spec- troscopy method was also investigated for the applicability to other common counterfeits, such as oyster shell powders and abalone shell powders, and the results show that the method can be a simple, efficiently and accurately method for identification of pearl powder.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(5): 1421-4, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25095451

RESUMO

In M star population, some special objects, which may be of magnetic activity, may be giant stars, or may be of other rare properties, are very important for the follow-up observation and the scientific research on galactic structure and evolution. For local bias of M-type star spectral characteristic lines contained in subspace, a late-type star spectra outlier data mining system is given in the present paper. Firstly, for the sample of M stellar spectral characteristic lines indices, its distribution characteristics in attribute spaces are measured by using the sparse factor and sparsity coefficient, and then this sample is discretized and dimension-reduced to the spectral subspace. Secondly, local outlier subspaces are extracted by PSO (particle swarm optimization) algorithm and identified. Additionally, the effects of sparse coefficient and sparse factor on the number of outliers are discussed by experiments on the sample of SDSS M stellar spectral line index set, and the outliers are compared with spectral type provided by SDSS. In this way, the feasibility and value of this system were validated.

17.
Exp Biol Med (Maywood) ; 239(12): 1589-96, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25107895

RESUMO

Subepithelial fibrosis is one of the common pathological features of asthmatic airway remodeling. During subepithelial fibrosis, type I collagen becomes the most abundant extracellular protein component. Studies have shown that Notch signaling participates in the progression of fibrosis; however, whether Notch signaling is involved in regulating type I collagen expression in airway fibroblasts remains unclear. The aim of the present study was to examine whether Notch signaling can regulate type I collagen expression in airway fibroblasts and to explore the underlying molecular mechanisms. Here, the expression of Notch signaling components was examined in mouse L929 cells and human MRC-5 cells. After upregulating or downregulating Notch signaling in these cell lines, col1α1 and col1α2 expression was examined. Using gene reporter assays, site-directed mutagenesis, and ChIP assays, the role of Hes1 binding sites in both the mouse and human COL1A1 and COL1A2 promoters was investigated. This study revealed that Notch signaling-related molecules (including Notch1, Hes1, and others) are expressed in L929 and MRC-5 cells and that Notch signaling regulates the expression of col1α1 and col1α2 in both cell lines. Additionally, over-expression of the Notch intracellular domain resulted in activation of the COL1A1 and COL1A2 promoters, and site-directed mutagenesis reporter assays revealed that Hes1 proteins might augment both mouse and human COL1A1 and COL1A2 promoter activity. Furthermore, ChIP assays confirmed that Hes1 binds to the COL1A1 and COL1A2 promoters in both L929 and MRC-5 cells. Therefore, it is reasonable to assume that Notch signaling can directly upregulate COL1A1 and COL1A2 promoter activity through a Hes1-dependent mechanism, which could serve as a possible target for pharmacotherapy of airway subepithelial fibrosis.


Assuntos
Colágeno Tipo I/biossíntese , Fibroblastos/fisiologia , Receptores Notch/metabolismo , Transdução de Sinais , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sítios de Ligação , Linhagem Celular , Imunoprecipitação da Cromatina , Regulação da Expressão Gênica , Genes Reporter , Proteínas de Homeodomínio/metabolismo , Humanos , Camundongos , Mutagênese Sítio-Dirigida , Regiões Promotoras Genéticas , Ligação Proteica , Fatores de Transcrição HES-1
18.
Mol Med Rep ; 10(2): 887-90, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24866503

RESUMO

Obesity increases the incidence, progression and mortality of breast cancer among postmenopausal females. This is partly due to excessive estrogen production in the adipose tissue of obese females. Aromatase is a key enzyme in estrogen biosynthesis. In the current study, the tensional force­triggered inducibility of aromatase expression was observed to vary in ASCs isolated from different disease­free individuals. In addition, this phenomenon was associated with the activation of the aromatase PII promoter and its DNA methylation load. These findings highlight the impact of tensional forces on estrogen biosynthesis in obese females.


Assuntos
Tecido Adiposo/enzimologia , Aromatase/metabolismo , Metilação de DNA , Tecido Adiposo/citologia , Aromatase/genética , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Técnicas de Cultura de Células , Células Cultivadas , Ilhas de CpG , Decitabina , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Obesidade/metabolismo , Obesidade/patologia , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo
19.
Cancer Sci ; 105(6): 660-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24673742

RESUMO

Metastasis is the leading cause of cancer-related death in almost all types of cancers, including colorectal cancer (CRC). Metastasis is a complex, multistep, dynamic biological event, and epithelial-mesenchymal transition (EMT) is a critical process during the cascade. Ajuba family proteins are LIM domain-containing proteins and are reported to be transcription repressors regulating different kinds of physiological processes. However, the expression and pathological roles of Ajuba family proteins in tumors, especial in tumor metastasis, remain poorly studied. Here, we found that JUB, but not the other Ajuba family proteins, was highly upregulated in clinical specimens and CRC cell lines. Ectopic expression of JUB induced EMT and enhanced motility and invasiveness in CRC, and vice versa. Mechanistic study revealed that JUB induces EMT via Snail and JUB is also required for Snail-induced EMT. The expression of JUB shows an inverse correlation with E-cadherin expression in clinical specimens. Taken together, these findings revealed that the LIM protein JUB serves as a tumor-promoting gene in CRC by promoting EMT, a critical process of metastasis. Thus, the LIM protein JUB may provide a novel target for therapy of metastatic CRC.


Assuntos
Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal , Proteínas com Domínio LIM/metabolismo , Células CACO-2 , Caderinas/biossíntese , Movimento Celular , Neoplasias Colorretais/genética , Células HCT116 , Humanos , Proteínas com Domínio LIM/genética , Invasividade Neoplásica , Metástase Neoplásica , Interferência de RNA , RNA Interferente Pequeno , Transdução de Sinais , Fatores de Transcrição da Família Snail , Esferoides Celulares/patologia , Fatores de Transcrição/metabolismo , Células Tumorais Cultivadas , Regulação para Cima
20.
PLoS One ; 9(2): e88796, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24558429

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common human malignancies and the third leading cause of cancer mortality worldwide. The development and progression of HCC is a complicated process, involving the deregulation of multiple genes that are essential to cell biological processes. Recently, microRNAs (miRNAs) have been suggested to be closely associated with tumorigenesis. Our study showed that miR-184 is upregulated in HCC cell lines and tissues. Overexpression of miR-184 in HCC cells increased cell proliferation, tumorigenicity, and cell cycle progression, whereas inhibition of miR-184 reduced cell proliferation, tumorigenicity, and cell cycle progression. Additionally, we identified SOX7 as a direct target of miR-184. Ectopic expression of miR-184 led to downregulation of the SOX7 protein, resulting in upregulation of c-Myc, Cyclin D1, and phosphorylation of Rb. Our findings suggested that miR-184 represents a potential onco-miR and plays an important role in HCC progression by suppressing SOX7 expression.


Assuntos
Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Fatores de Transcrição SOXF/genética , Sequência de Bases , Carcinogênese/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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