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1.
Acad Radiol ; 30 Suppl 2: S50-S61, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37270368

RESUMO

RATIONALE AND OBJECTIVES: To carry out radiomics analysis/deep convolutional neural network (CNN) based on B-mode ultrasound (BUS) and shear wave elastography (SWE) to predict response to neoadjuvant chemotherapy (NAC) in breast cancer patients. MATERIALS AND METHODS: In this prospective study, 255 breast cancer patients who received NAC between September 2016 and December 2021 were included. Radiomics models were designed using a support vector machine classifier based on US images obtained before treatment, including BUS and SWE. And CNN models also were developed using ResNet architecture. The final predictive model was developed by combining the dual-modal US and independently associated clinicopathologic characteristics. The predictive performances of the models were assessed with five-fold cross-validation. RESULTS: Pretreatment SWE performed better than BUS in predicting the response to NAC for breast cancer for both the CNN and radiomics models (P < 0.001). The predictive results of the CNN models were significantly better than the radiomics models, with AUCs of 0.72 versus 0.69 for BUS and 0.80 versus 0.77 for SWE, respectively (P = 0.003). The CNN model based on the dual-modal US and molecular data exhibited outstanding performance in predicting NAC response, with an accuracy of 83.60% ± 2.63%, a sensitivity of 87.76% ± 6.44%, and a specificity of 77.45% ± 4.38%. CONCLUSION: The pretreatment CNN model based on the dual-modal US and molecular data achieved excellent performance for predicting the response to chemotherapy in breast cancer. Therefore, this model has the potential to serve as a non-invasive objective biomarker to predict NAC response and aid clinicians with individual treatments.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Terapia Neoadjuvante , Estudos Prospectivos , Ultrassonografia/métodos , Estudos Retrospectivos
2.
Cell Biosci ; 12(1): 143, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36056448

RESUMO

BACKGROUND: Induced hepatic stem cells (iHepSCs) with the capacities of self-renewal and bidifferentiation into hepatocytes and cholangiocytes were generated from mouse embryonic fibroblasts (MEFs) by lineage reprogramming in our previous research. However, the mechanism of iHepSC self-renewal has not been elucidated. Active demethylation regulated by Tet1 plays an important role in the self-renewal of stem cells, including pluripotent stem cells and adult stem cells. Here, we investigated the role and mechanism of Tet1-regulated demethylation in the self-renewal of iHepSCs. METHODS: The methylation levels and the expression of Tet1 in iHepSCs and MEFs were analyzed by immunofluorescent staining, quantitative reverse transcription PCR and western blotting. Then, the effects of Tet1 knockdown on the proliferation and self-renewal of iHepSCs were analyzed by CCK8, colony formation, and sphere formation assays. The mechanism by which Tet1 regulates the self-renewal of iHepSCs was investigated by chromatin immunoprecipitation, bisulfite sequence PCR, and methylation-sensitive restriction endonuclease-PCR. RESULTS: The high level of 5hmC and the low level of 5mC in iHepSCs were accompanied by high expression of Tet1. After Tet1 expression was knocked down by shRNA in iHepSCs, the proliferation and self-renewal capacities were inhibited, and the expression of Myc was also decreased. The higher expression level of Myc in iHepSCs maintained its self-renewal and was regulated by Tet1, which directly binds to CBS-1 and site A regions of the Myc promoter and demethylates the CpG cytosine. In addition, CTCF also binds to the CBS-1 and site A regions of the Myc promoter and regulates Myc expression along with TET1. CONCLUSION: The self-renewal of iHepSCs was maintained by the higher expression of Myc, which was coregulated by TET1 and CTCF. This study may provide new insights into the self-renewal of stem cells, which can promote the research and application of 'reprogrammed' stem cells.

3.
Appl Microbiol Biotechnol ; 105(9): 3635-3648, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33852023

RESUMO

Biofilms are a form of microbial community that can be beneficial for industrial fermentation because of their remarkable environmental resistance. However, the mechanism of biofilm formation in Saccharomyces cerevisiae remains to be fully explored, and this may enable improved industrial applications for this organism. Although quorum-sensing (QS) molecules are known to be involved in bacteria biofilm formation, few studies have been undertaken with these in fungi. 2-phenylethanol (2-PE) is considered a QS molecule in S. cerevisiae. Here, we found that exogenous 2-PE could stimulate biofilm formation at low cell concentrations. ARO8p and ARO9p are responsible for the synthesis of 2-PE and were crucial to the formation of biofilm. Deletion of the ARO8 and ARO9 genes reduced the content of 2-PE in the early stage of fermentation, reduced ethanol yield and decreased biofilm formation. The expression of FLOp, which is involved in cell adhesion, and the content of extracellular polysaccharides of mutant strains ΔARO8 and ΔARO9 were also significantly reduced. These findings indicate that the production of 2-PE had a positive effect on biofilm formation in S. cerevisiae, thereby providing further key details for studying the formation of biofilm mechanism in the future. KEY POINTS: • Quorum-sensing molecule 2-PE positively affects biofilm formation in S. cerevisiae. • 2-PE synthetic genes ARO8 and ARO9 deletion reduced extracellular polysaccharide. • ARO8 and ARO9 deletion reduced the gene expression of the FLO family.


Assuntos
Álcool Feniletílico , Proteínas de Saccharomyces cerevisiae , Biofilmes , Percepção de Quorum , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Transaminases
4.
FEBS Open Bio ; 10(12): 2733-2739, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33091216

RESUMO

In the paper industry, chlorine is often used to treat the pulp for bleaching. After pulping, a large amount of xylan is present in the fiber. Xylanase can be used to degrade xylan in an eco-friendly process called biobleaching, which can help minimize the usage of chlorine in the delignification process. However, a bottleneck in the adoption of biobleaching is the cost of xylanase and the requirement that xylanase be active and stable at extreme conditions. Here, we investigated whether using sodium alginate beads to immobilize an extracellular xylanase from Bacillus subtilis (Lucky9) can reduce the potential cost of enzyme usage. The optimal pH and the activity of the immobilized enzyme were increased at optimal temperature compared with the free enzyme. In addition, immobilized xylanase was shown to be more stable than free xylanase. The results of this study suggest that the immobilized xylanase has potential applications in the biobleaching industry.


Assuntos
Bacillus subtilis/enzimologia , Endo-1,4-beta-Xilanases/metabolismo , Enzimas Imobilizadas/metabolismo , Concentração de Íons de Hidrogênio , Temperatura , Xilanos/metabolismo
5.
Appl Microbiol Biotechnol ; 104(17): 7495-7505, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32666184

RESUMO

Biofilm-based fermentation, as a new immobilisation strategy, is beneficial for industrial fermentation due to its excellent environmental resistance, high productivity and continuous fermentation relative to calcium alginate-immobilised fermentation. These two techniques differ mainly regarding cell stages. Here, we describe the cell phenotype of Saccharomyces cerevisiae biofilm-based fermentation and compare cell cycle stages with those during immobilisation in calcium alginate. Most cells in the biofilm-based fermentation adhered to the cotton-fibre carrier of the biofilm and were in the G2/M phase whereas alginate-embedded cells were in the G1/G0 phase. Deletion of the RIM15 gene, which regulates cell cycle progression according to nutritional status, hampered the cell cycle arrest observed in alginate-embedded cells, enhanced biofilm formation and improved fermentation ability. The improved biofilm formation shown by the rim15△ strain could be attributed to an increase in the expression level of the adhesion protein FLO11 and synthesis of trehalose. These findings suggest that the extracellular environment is mainly responsible for the difference between biofilm-based fermentation and alginate-embedded fermentation, and that RIM15 plays an essential role in cell cycle progression. KEY POINTS: • In the biofilm, S. cerevisiae cell populations were mostly in the G2/M phase while alginate-embedded cells were arrested in the G1/G0 phase. • The RIM15 gene partially influenced the cell cycle progression observed during ethanol fermentation. • Biofilm-based cells were actively adsorbed on the physical carrier. • Biofilm immobilisation could maintain cell division activity explaining its fermentation efficiency.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Biofilmes , Divisão Celular , Etanol , Fermentação , Proteínas Quinases/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
6.
Acta Biomater ; 71: 184-199, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29355717

RESUMO

Localization of recombinant human bone morphogenetic protein-2 (rhBMP-2) with continuous and effective osteogenic stimulation is still a great challenge in the field of bone regeneration. To achieve this aim, rhBMP-2 was tethered on chondroitin sulfate (CS)-functionalized calcium phosphate cement (CPC) scaffolds through specific noncovalent interactions. CS, one of the core glycosaminoglycans, was covalently conjugated onto CPC scaffolds with the assistance of polydopamine (PDA) and further immobilized rhBMP-2 in a biomimetic form. The CPC-PDA-CS scaffolds not only controlled the release kinetics and presentation state of rhBMP-2 but also effectively increased the expression levels of bone morphogenetic protein receptors (BMPRs) and enhanced the recognitions of the remaining rhBMP-2 to BMPRs. Strikingly, the rhBMP-2-loaded CPC-PDA-CS significantly promoted the cellular surface translocation of BMPRs (especially BMPR-IA). In vivo studies demonstrated that, compared with the rhBMP-2 upon CPC and CPC-PDA, the rhBMP-2 upon CPC-PDA-CS exhibited sustained release and induced high quality and more ectopic bone formation. Collectively, these results suggest that rhBMP-2 can be localized within CS-functionalized CPC scaffolds and exert continuous, long-term, and effective osteogenic stimulation. Thus, this work could provide new avenues in mimicking bone extracellular matrix microenvironment and localizing growth factor activity for enhanced bone regeneration. STATEMENT OF SIGNIFICANCE: A bioinspired chondroitin sulfate (CS)-functionalized calcium phosphate cement (CPC) platform was developed to tether recombinant human bone morphogenetic protein-2 (rhBMP-2), which could exhibit continuous, long-term, and effective osteogenic stimulation in bone tissue engineering. Compared with rhBMP-2-loaded CPC, the rhBMP-2-loaded CPC-polydopamine-CS scaffolds induced higher expression of bone morphogenetic protein receptors (BMPRs), greater cellular surface translocation of bone morphogenetic protein receptor-IA, higher binding affinity of BMPRs/rhBMP-2, and thus higher activation of the drosophila gene mothers against decapentaplegic protein-1/5/8 (Smad1/5/8) and extracellular-regulated protein kinases-1/2 (ERK1/2) signaling. This work can provide new guidelines for the design of BMP-2-based bioactive materials for bone regeneration.


Assuntos
Cimentos Ósseos/química , Proteína Morfogenética Óssea 2 , Fosfatos de Cálcio/química , Sulfatos de Condroitina/química , Matriz Extracelular/química , Animais , Proteína Morfogenética Óssea 2/química , Proteína Morfogenética Óssea 2/farmacocinética , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacocinética
7.
Artigo em Inglês | MEDLINE | ID: mdl-30417075

RESUMO

This paper provides a unique illustration of the benefits of affirmative action in higher educaiton. It focuses on China in the early 21st Century to gauge the impacts of advantges afforded to ethnic minority group members in admissions to colleges and univerities. It specifically addresses a variant of the mismatch hypothesis that alleges that minority students sorted into higher ranked universities are worse off than equallty qualified minorities attending lower-ranked universities. In particular, we examine the expected earnings of minorities vs non-minorities attending elite vs less selective colleges and universities in China. The paper utilizes data from the 2002 Chinese Household Income Project to estimate the labor market return to graduating from college relative to high school to assess the impact of post-reform affirmative action in college/univerity admissions in China. Parameter estimates of heterogeneous treatment effects reveal that for minorities, the average treatment effect of earning a baccalaureate degree from colleges/universities ranked good and very good is high relative to the Han majority, and for those actually receiving the treatment from colleges/universities ranked good, and would be positive for those who could have earned a baccalaureate degree from colleges/universities ranked good and very good, but did not. Our results suggest that post-reform affirmative action education policies in China have been effective at improving the education and labor market outcomes of minorities, and that existing minority-Han disparities can be eliminated, and Chinese economic growth can be enhanced, by further expanding the pipeline of minorities that complete high school and enter into colleges/universities that grant baccalaureate degrees. Our findings suggest that the mismatch hypothesis cannot be viewed as a universal phenomenon that renders affirmative action in college/university admissions an ineffective policy tool to redress/remedy historic discrimination against minority groups.

8.
Colloids Surf B Biointerfaces ; 145: 140-151, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27156155

RESUMO

Efficient presentation of growth factors is one of the great challenges in tissue engineering. In living systems, bioactive factors exist in soluble as well as in matrix-bound forms, both of which play an integral role in regulating cell behaviors. Herein, effect of magnesium on osteogenic bioactivity of recombinant human bone morphogenetic protein-2 (rhBMP-2) was investigated systematically with a series of Mg modified calcium phosphate cements (xMCPCs, x means the content of magnesium phosphate cement wt%) as matrix model. The results indicated that the MCPC, especially 5MCPC, could promote the rhBMP-2-induced in vitro osteogenic differentiation via Smad signaling of C2C12 cells. Further studies demonstrated that all MCPC substrates exhibited similar rhBMP-2 release rate and preserved comparable conformation and biological activity of the released rhBMP-2. Also, the ionic extracts of MCPC made little difference to the bioactivity of rhBMP-2, either in soluble or in matrix-bound forms. However, with the quartz crystal microbalance (QCM), we observed a noticeable enhancement of rhBMP-2 mass-uptake on 5MCPC as well as a better recognition of the bound rhBMP-2 to BMPR IA and BMPR II. In vivo results demonstrated a better bone regeneration capacity of 5MCPC/rhBMP-2. From the above, our results demonstrated that it was the Mg anchored on the underlying substrates that tailored the way of rhBMP-2 bound on MCPC, and thus facilitated the recognition of BMPRs to stimulate osteogenic differentiation. The study will guide the development of Mg-doped bioactive bone implants for tissue regeneration.


Assuntos
Proteína Morfogenética Óssea 2/química , Proteína Morfogenética Óssea 2/farmacologia , Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Fosfatos de Cálcio/química , Magnésio/química , Fator de Crescimento Transformador beta/química , Fator de Crescimento Transformador beta/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Magnésio/farmacologia , Osteogênese/efeitos dos fármacos , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos
9.
Sci Rep ; 6: 24323, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-27075233

RESUMO

Biomaterial surface functionalized with bone morphogenetic protein-2 (BMP-2) is a promising approach to fabricating successful orthopedic implants/scaffolds. However, the bioactivity of BMP-2 on material surfaces is still far from satisfactory and the mechanism of related protein-surface interaction remains elusive. Based on the most widely used bone-implants/scaffolds material, hydroxyapatite (HAP), we developed a matrix of magnesium-substituted HAP (Mg-HAP, 2.2 at% substitution) to address these issues. Further, we investigated the adsorption dynamics, BMPRs-recruitment, and bioactivity of recombinant human BMP-2 (rhBMP-2) on the HAP and Mg-HAP surfaces. To elucidate the mechanism, molecular dynamic simulations were performed to calculate the preferred orientations, conformation changes, and cysteine-knot stabilities of adsorbed BMP-2 molecules. The results showed that rhBMP-2 on the Mg-HAP surface exhibited greater bioactivity, evidenced by more facilitated BMPRs-recognition and higher ALP activity than on the HAP surface. Moreover, molecular simulations indicated that BMP-2 favoured distinct side-on orientations on the HAP and Mg-HAP surfaces. Intriguingly, BMP-2 on the Mg-HAP surface largely preserved the active protein structure evidenced by more stable cysteine-knots than on the HAP surface. These findings explicitly clarify the mechanism of BMP-2-HAP/Mg-HAP interactions and highlight the promising application of Mg-HAP/BMP-2 matrixes in bone regeneration implants/scaffolds.


Assuntos
Materiais Biocompatíveis/metabolismo , Proteína Morfogenética Óssea 2/metabolismo , Durapatita/metabolismo , Magnésio/metabolismo , Propriedades de Superfície , Adsorção , Materiais Biocompatíveis/química , Proteína Morfogenética Óssea 2/química , Proteína Morfogenética Óssea 2/genética , Humanos , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
10.
Acta Biomater ; 27: 275-285, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26360594

RESUMO

Highly efficient loading of bone morphogenetic protein-2 (BMP-2) onto carriers with desirable performance is still a major challenge in the field of bone regeneration. Till now, the nanoscaled surface-induced changes of the structure and bioactivity of BMP-2 remains poorly understood. Here, the effect of nanoscaled surface on the adsorption and bioactivity of BMP-2 was investigated with a series of hydroxyapatite surfaces (HAPs): HAP crystal-coated surface (HAP), HAP crystal-coated polished surface (HAP-Pol), and sintered HAP crystal-coated surface (HAP-Sin). The adsorption dynamics of recombinant human BMP-2 (rhBMP-2) and the accessibility of the binding epitopes of adsorbed rhBMP-2 for BMP receptors (BMPRs) were examined by a quartz crystal microbalance with dissipation. Moreover, the bioactivity of adsorbed rhBMP-2 and the BMP-induced Smad signaling were investigated with C2C12 model cells. A noticeably high mass-uptake of rhBMP-2 and enhanced recognition of BMPR-IA to adsorbed rhBMP-2 were found on the HAP-Pol surface. For the rhBMP-2-adsorbed HAPs, both ALP activity and Smad signaling increased in the order of HAP-Sin

Assuntos
Proteína Morfogenética Óssea 2/administração & dosagem , Proteína Morfogenética Óssea 2/química , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/química , Materiais Revestidos Biocompatíveis/síntese química , Durapatita/química , Nanocápsulas/química , Adsorção , Sítios de Ligação , Difusão , Teste de Materiais , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Nanocápsulas/ultraestrutura , Tamanho da Partícula , Ligação Proteica , Propriedades de Superfície
11.
J Rehabil Med ; 47(7): 586-92, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26121925

RESUMO

OBJECTIVE: To determine the physical, functional and psychosocial rehabilitation needs of the injured survivors of the 2013 earthquake in Ya'an, China. DESIGN: Cross-sectional survey. METHODS: A total of 143 injured survivors (80 males, 63 females, mean age 41.4 years (standard deviation (SD) 20.2)) were recruited for the study. A questionnaire was designed to collect their demographic and environmental information. Manual muscle testing and active range of motion (AROM) were used to assess physical function. The Modified Barthel Index was used to assess activities of daily living (ADL) and the Post-Traumatic Stress Disorder - Self Rating Scale was used to assess psychological status. The rehabilitation needs of the injured survivors were identified based on the assessment results. RESULTS: Physical problems of the back and lower limbs were more severe than those of the upper limbs, as measured by MMT and AROM. Various degrees of dependence in ADL were measured in 74.2% of subjects, and psychological distress was present in more than 50% of subjects. Rehabilitation training prescribed by local therapists included functional training (74.8%), exercises (49.0%), provision of splints (44.8%), etc. Psychological interventions were re-commended to most of the patients. There were high levels of need for assistive devices, and home and community modifications. CONCLUSION: There is a high level of need for early rehabilitation in hospital, followed by continued home and community rehabilitation services, particularly for injured survivors who are returning to villages with very limited resources.


Assuntos
Vítimas de Desastres/reabilitação , Terremotos , Sobreviventes/psicologia , Adulto , China , Estudos Transversais , Feminino , Humanos , Masculino , Avaliação das Necessidades , Transtornos de Estresse Pós-Traumáticos , Inquéritos e Questionários
12.
Zhong Xi Yi Jie He Xue Bao ; 8(2): 158-67, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20141739

RESUMO

OBJECTIVE: To investigate the effects of Yiguanjian Decoction, a compound traditional Chinese herbal medicine, on rats with cirrhosis based on the method of differential proteomics. METHODS: Wistar male rats (n=48) were randomly divided into normal control group (n=12) and model-making group (n=36). Rat cirrhosis model was established by intraperitoneal injection of 50% carbon tetrachloride (CCl4) plus olive oil solution (1 mL/kg, twice weekly for 9 weeks). After 3- and 6-week injection, 6 rats each time were sacrificed for dynamic observation before medicine intervention, and the 24 remained rats were randomly divided into untreated group (n=12) and Yiguanjian Decoction group (n=12) at the first day of the 7th week. All animals were sacrificed by the end of the 9th week, and total protein of liver tissue was isolated by two-dimensional gel electrophoresis (2-DE); some differentially expressed protein spots were analyzed and identified by matrix-assisted laser desorption/ionization two-stage time-of-flight mass spectrometry (MALDI-TOF/TOF-MS) and database querying. Protein expressions of Cu/Zn superoxide dismutase (Cu/Zn SOD) and DJ-1 were validated by Western blot and immunohistochemical methods. RESULTS: 2-DE maps with high resolution and good repeatability were obtained. In all 50 protein spots identified by MALDI-TOF/TOF-MS and database querying, there were 5 protein spots related to oxidative stress named Cu/Zn SOD, DJ-1, glutathione synthetase, glutathione S-transferase Yb-1 subunit and aldo-keto reductase family 7, A2 respectively. Compared with the normal control group, expressions of Cu/Zn SOD, DJ-1, glutathione S-transferase Yb-1 subunit and aldo-keto reductase family 7, A2 in the untreated group were decreased significantly. Expressions of Cu/Zn SOD and aldo-keto reductase family 7, A2 were decreased time-dependently. Compared with the untreated group in 9th week, protein expressions of Cu/Zn SOD, DJ-1, glutathione S-transferase Yb-1 subunit and aldo-keto reductase family 7, A2 in the Yiguanjian Decoction groups were increased significantly while expression of glutathione synthetase was decreased notably. Western blot and immunohistochemical results of Cu/Zn SOD and DJ-1 expressions coincided with proteomics results. CONCLUSION: Anti-oxidative depression is a key pathological change of cirrhosis induced by CCl4 in rats, and increasing expression of proteins related to anti-oxidative stress may be a major mechanism of Yiguanjian Decoction in treating cirrhosis induced by CCl4 effectively.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Estresse Oxidativo/efeitos dos fármacos , Proteoma/metabolismo , Animais , Medicamentos de Ervas Chinesas/uso terapêutico , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/tratamento farmacológico , Masculino , Fitoterapia , Proteômica , Ratos , Ratos Wistar
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