Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Metab Eng ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019249

RESUMO

Heme has attracted considerable attention due to its indispensable biological roles and applications in healthcare and artificial foods. The development and utilization of edible microorganisms instead of animals to produce heme is the most promising method to promote the large-scale industrial production and safe application of heme. However, the cytotoxicity of heme severely restricts its efficient synthesis by microorganisms, and the cytotoxic mechanism is not fully understood. In this study, the effect of heme toxicity on Saccharomyces cerevisiae was evaluated by enhancing its synthesis using metabolic engineering. The results showed that the accumulation of heme after the disruption of heme homeostasis caused serious impairments in cell growth and metabolism, as demonstrated by significantly poor growth, mitochondrial damage, cell deformations, and chapped cell surfaces, and these features which were further associated with substantially elevated reactive oxygen species (ROS) levels within the cell (mainly H2O2 and superoxide anion radicals). To improve cellular tolerance to heme, 5 rounds of laboratory evolution were performed, increasing heme production by 7.3-fold and 4.2-fold in terms of the titer (38.9 mg/L) and specific production capacity (1.4 mg/L/OD600), respectively. Based on comparative transcriptomic analyses, 32 genes were identified as candidates that can be modified to enhance heme production by more than 20% in S. cerevisiae. The combined overexpression of 5 genes (SPS22, REE1, PHO84, HEM4 and CLB2) was shown to be an optimal method to enhance heme production. Therefore, a strain with enhanced heme tolerance and ROS quenching ability (R5-M) was developed that could generate 380.5 mg/L heme with a productivity of 4.2 mg/L/h in fed-batch fermentation, with S. cerevisiae strains being the highest producers reported to date. These findings highlight the importance of improving heme tolerance for the microbial production of heme and provide a solution for efficient heme production by engineered yeasts.

2.
Toxicol Appl Pharmacol ; 483: 116827, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38246290

RESUMO

With the increasing incidence of chronic kidney disease (CKD), the development of safe and effective anti-renal fibrosis drugs is particularly urgent. Recently, Baicalin has been considered to have a renal protective effect, but its bioavailability is too low. Therefore, we synthesized baicalin-2-ethoxyethyl ester (BAE) by esterification of baicalin. We hope that this experiment will demonstrate the anti-renal fibrosis effect of BAE and explain its molecular mechanism. In this study, the chronic kidney injury model of SD rats was established by 5/6 nephrectomy, and BAE was given for 28 days. The results showed that after BAE treatment, the serum creatinine and urea nitrogen levels decreased significantly, and the pathological changes in kidneys were improved. In addition, RNA-seq analysis showed that the mechanism of BAE in relieving renal fibrosis was related to the ECM receptor, PI3K/AKT signaling pathway, and inflammatory reaction. The western blotting analysis confirmed that BAE could inhibit the expression of α-SMA, TGF-ß1, p-PI3K, p-AKT, p-IκBα, and NF-κB p65. We found that BAE can inhibit the inflammatory reaction and promote the degradation of the extracellular matrix by inhibiting the activation of the PI3K/AKT/NF-κB pathway, thus alleviating the symptoms of renal fibrosis in 5/6Nx rats, which revealed BAE was a potential compound to relieve renal fibrosis effect.


Assuntos
Flavonoides , NF-kappa B , Insuficiência Renal Crônica , Ratos , Animais , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Ésteres/farmacologia , Ratos Sprague-Dawley , Transdução de Sinais , Fibrose , Inflamação
3.
Sensors (Basel) ; 23(24)2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38139672

RESUMO

Integrated TLS and GPR data can provide multisensor and multiscale spatial data for the comprehensive identification and analysis of surficial and subsurface information, but a reliable systematic methodology associated with data integration of TLS and GPR is still scarce. The aim of this research is to develop a methodology for the data integration of TLS and GPR for detailed, three-dimensional (3D) virtual reconstruction. GPR data and high-precision geographical coordinates at the centimeter level were simultaneously gathered using the GPR system and the Global Navigation Satellite System (GNSS) signal receiver. A time synchronization algorithm was proposed to combine each trace of the GPR data with its position information. In view of the improved propagation model of electromagnetic waves, the GPR data were transformed into dense point clouds in the geodetic coordinate system. Finally, the TLS-based and GPR-derived point clouds were merged into a single point cloud dataset using coordinate transformation. In addition, TLS and GPR (250 MHz and 500 MHz antenna) surveys were conducted in the Litang fault to assess the feasibility and overall accuracy of the proposed methodology. The 3D realistic surface and subsurface geometry of the fault scarp were displayed using the integration data of TLS and GPR. A total of 40 common points between the TLS-based and GPR-derived point clouds were implemented to assess the data fusion accuracy. The difference values in the x and y directions were relatively stable within 2 cm, while the difference values in the z direction had an abrupt fluctuation and the maximum values could be up to 5 cm. The standard deviations (STD) of the common points between the TLS-based and GPR-derived point clouds were 0.9 cm, 0.8 cm, and 2.9 cm. Based on the difference values and the STD in the x, y, and z directions, the field experimental results demonstrate that the GPR-derived point clouds exhibit good consistency with the TLS-based point clouds. Furthermore, this study offers a good future prospect for the integration method of TLS and GPR for comprehensive interpretation and analysis of the surficial and subsurface information in many fields, such as archaeology, urban infrastructure detection, geological investigation, and other fields.

4.
Biomed Pharmacother ; 172: 116276, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377733

RESUMO

Drug nephrotoxicity has high fatality rates and complications. To study this conditional, traditionally, Gentamicin (GM) is used to induce acute injury and establish a nephrotic syndrome model. Baicalin, a flavonoid derived from baicalin with potent anti-inflammatory and antioxidant activity, has been used to treat various inflammatory diseases. This study aims to investigate the process of baicalin-2-ethoxyethyl ester (BAE) synthesis and its therapeutic effect on GM-induced acute kidney injury (AKI). Briefly, baicalin was processed by various reactions to yield BAE. A GM-induced AKI model was established for in vivo evaluation of the protective effect and mechanism of BAE. The results indicated that BAE reduced serum creatinine and urea nitrogen levels and improved pathological alterations, inflammatory responses, and oxidative stress in renal tissues. Furthermore, it was revealed that BAE might exert anti-inflammatory and anti-oxidative responses during AKI via the NF-κB signaling pathway regulation. The findings imply that BAE has a protective impact on the kidneys and might serve as a potent medicine for treating renal damage.


Assuntos
Injúria Renal Aguda , Flavonoides , Transdução de Sinais , Humanos , Injúria Renal Aguda/tratamento farmacológico , Anti-Inflamatórios/efeitos adversos , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Gentamicinas/toxicidade , NF-kappa B/metabolismo
5.
Acad Radiol ; 30(4): 717-726, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35953356

RESUMO

RATIONALE AND OBJECTIVES: To develop, validate, and test a comprehensive radiomics prediction model to distinguish parotid polymorphic adenomas (PAs) and warthin tumors (WTs) using clinical data and enhanced computed tomography (CT) from a multicenter cohort. MATERIALS AND METHODS: A total of 267 patients with PAs (n =172) or WTs (n = 95) from two hospitals were randomly divided into training (n =188) and validation (n =79) datasets. Radiomics features were extracted from the enhanced CT (arterial phase) followed by dimensionality reduction. Clinical and CT features were combined to establish a prediction model. A radiomics nomogram was constructed by combining RadScore and clinical factors. Moreover, an independent dataset of 31 patients from a third hospital was employed to test the model. Thus, the performance of the nomogram, radiomics signature, and clinical models was evaluated on the training, validation, and the independent testing datasets. Receiver operating characteristic (ROC) curves were used to compare the performance, and decision curve analysis (DCA) was used to evaluate the clinical effectiveness of the model. RESULTS: A total of 15 radiomics features were selected from CT data as the imaging markers to generate RadScores, and demographics or clinical data like age, sex, and smoking factors combined with RadScores were used to distinguish PAs and WTs based on multivariate logistic regression analyses. The results showed that radiomics nomograms combining clinical factors and RadScores provided satisfactory predictive values for distinguishing PAs from WTs, with areas under ROC curves (AUC) of 0.979, 0.922, and 0.903 for the training, validation, and the independent testing datasets, respectively. Decision curve analysis revealed that the radiomics nomogram outperformed the clinical factor models in terms of accuracy and effectiveness. CONCLUSION: CT-based radiomics nomograms combining RadScores and clinical factors can be used to identify PAs and WTs, which may help tumor management by clinicians.


Assuntos
Adenolinfoma , Adenoma , Humanos , Nomogramas , Adenolinfoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Artérias , Adenoma/diagnóstico por imagem , Estudos Retrospectivos
7.
Int J Clin Exp Pathol ; 8(5): 5300-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26191231

RESUMO

OBJECTIVES: XB130 is involved in gene regulation, cell proliferation, cell survival, cell migration, and tumorigenesis. In the present study, we first evaluated the expression of the XB130 and its prognostic significance in breast cancer. Then we evaluated whether XB130 could be a target for therapy in breast cancer. MATERIALS AND METHODS: Immunohistochemistry was used to assess the level of XB130 protein in surgically resected, formalin-fixed, paraffin-embedded breast cancer specimens. Associations between XB130 and the postoperative prognosis of patients with breast cancer were evaluated. We evaluated the effect of XB130 inhibited by RNA interference on proliferation, invasion and apoptosis in vitro in a metastatic subclone of MCF-7 breast cancer cell line (LM-MCF-7). The effect of XB130 silencing alone or in combination with gemcitabine on LM-MCF-7 cells apoptosis was also investigated. RESULTS: XB130 protein was present in the cytoplasm of malignant cells, and not in the normal breast tissues. There was correlation between the presence of XB130 in tumour cells and lymph node status, tumor classification and clinical stage. XB130 expression level was significantly associated with recurrence-free and overall survival. Furthermore, multivariate Cox regression analyses revealed that positive XB130 was an independent risk factor for overall survival and recurrence free survival. XB130 silencing alone inhibits tumor growth and induces apoptosis in the LM-MCF-7 cells. Depletion of the XB130 in combination with gemcitabine resulted in marked apoptotic and necrotic cell death in LM-MCF-7 cells. CONCLUSIONS: XB130 could be useful as a prognostic marker of recurrence-free and overall survival in invasive breast cancer, as well as for the response to chemotherapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Antimetabólitos Antineoplásicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/secundário , Carcinoma Ductal de Mama/terapia , Movimento Celular , Proliferação de Células , Distribuição de Qui-Quadrado , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Células MCF-7 , Mastectomia , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Interferência de RNA , Fatores de Risco , Transdução de Sinais , Fatores de Tempo , Transfecção , Resultado do Tratamento , Regulação para Cima , Gencitabina
8.
Int J Clin Exp Pathol ; 8(5): 4923-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26191185

RESUMO

BACKGROUND AND OBJECTIVE: Ovarian cancer is among the most lethal of all malignancies in women. While chemotherapy is the preferred treatment modality, chemoresistance severely limits treatment success. Because transforming growth factor-beta (TGF-ß) could increase survival of ovarian cancer cells in the presence of cisplatin, we conducted a preclinical study of the antitumor effects of the TGF-ß type I (TßRI) and type II (TßRII) kinase inhibitor LY2109761 in combination with cisplatin. METHODS: SKOV3, OV-90 and SKOV3(DDP) cells were treated with LY2109761, and/or cisplatin, and cell viability, apoptosis mRNA and protein expression levels were then evaluated. Furthermore, the efficacy of LY2109761 combined with cisplatin was further examined in established xenograft models. RESULTS: LY2109761 was sufficient to induce spontaneous apoptosis of ovarian cancer cells. Combination with LY2109761 significantly augmented the cytotoxicity of cisplatin in both parental and cisplatin resistant ovarian cancer cells. LY2109761 significantly increased apoptotic cell death in cisplatin-resistant cells. Combination treatment of LY2109761 and cisplatin showed antiproliferative effects and induced a greater rate of apoptosis than the sum of the single-treatment rates and promoted tumor regression in established parental and cisplatin resistant ovarian cancer xenograft models. CONCLUSIONS: Chemotherapeutic approaches using LY2109761 might enhance the treatment benefit of the cisplatin in the treatment of ovarian cancer patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Cisplatino/farmacologia , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Pirróis/farmacologia , Animais , Apoptose/efeitos dos fármacos , Carcinoma Epitelial do Ovário , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Camundongos Endogâmicos ICR , Camundongos SCID , Neoplasias Epiteliais e Glandulares/enzimologia , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/enzimologia , Neoplasias Ovarianas/patologia , Fosforilação , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Smad2/metabolismo , Fatores de Tempo , Fator de Crescimento Transformador beta/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA