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1.
Breast Cancer Res ; 26(1): 10, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-38217030

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) remains the most challenging subtype of breast cancer and lacks definite treatment targets. Aerobic glycolysis is a hallmark of metabolic reprogramming that contributes to cancer progression. PFKP is a rate-limiting enzyme involved in aerobic glycolysis, which is overexpressed in various types of cancers. However, the underlying mechanisms and roles of the posttranslational modification of PFKP in TNBC remain unknown. METHODS: To explore whether PFKP protein has a potential role in the progression of TNBC, protein levels of PFKP in TNBC and normal breast tissues were examined by CPTAC database analysis, immunohistochemistry staining (IHC), and western blotting assay. Further CCK-8 assay, colony formation assay, EDU incorporation assay, and tumor xenograft experiments were used to detect the effect of PFKP on TNBC progression. To clarify the role of the USP5-PFKP pathway in TNBC progression, ubiquitin assay, co-immunoprecipitation (Co-IP), mass spectrometry-based protein identification, western blotting assay, immunofluorescence microscopy, in vitro binding assay, and glycolysis assay were conducted. RESULTS: Herein, we showed that PFKP protein was highly expressed in TNBC, which was associated with TNBC progression and poor prognosis of patients. In addition, we demonstrated that PFKP depletion significantly inhibited the TNBC progression in vitro and in vivo. Importantly, we identified that PFKP was a bona fide target of deubiquitinase USP5, and the USP5-mediated deubiquitination and stabilization of PFKP were essential for cancer cell aerobic glycolysis and TNBC progression. Moreover, we found a strong positive correlation between the expression of USP5 and PFKP in TNBC samples. Notably, the high expression of USP5 and PFKP was significantly correlated with poor clinical outcomes. CONCLUSIONS: Our study established the USP5-PFKP axis as an important regulatory mechanism of TNBC progression and provided a rationale for future therapeutic interventions in the treatment of TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Glicólise , Xenoenxertos , Transplante Heterólogo , Neoplasias de Mama Triplo Negativas/patologia
2.
Apoptosis ; 28(3-4): 348-361, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36370260

RESUMO

Oral squamous cell carcinoma (OSCC) is a malignant tumor with high mortality and poor prognosis. Many OSCC patients have low response rate to current treatments including immunotherapies largely due to the immune-suppressive tumor microenvironment (TME). Chemotherapy could induce immunogenic cell death (ICD), a type of cell death such as pyroptosis and necroptosis, which has proved to be capable to alter the immune-suppressive TME and beneficial for better anti-tumor effect. GSDME, a key protein of pyroptosis, is however often silenced in tumors due to abnormal methylation. To overcome these limitations, we utilizied methyltransferase inhibitor (decitabine, DAC) to trigger pyroptosis of tumor cells, combined with chemodrug cisplatin (DDP) and immune checkpoints inhibitors to amplify the immunotherapies outcomes. To the best of our knowledge, this is the first study of tumor suppressive effect of GSDME in OSCC. Our investigation demonstrated that stimulation of GSDME expression could improve the sensitivity of chemotherapeutics, activate inflammatory tumor cell pyroptosis and alter the tumor immune-suppressive microenvironment, providing an important perspective for clinical OSCC treatment.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Piroptose , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Apoptose , Gasderminas , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Linhagem Celular Tumoral , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , Microambiente Tumoral
3.
Brief Bioinform ; 22(4)2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-33279983

RESUMO

The protein Yin Yang 1 (YY1) could form dimers that facilitate the interaction between active enhancers and promoter-proximal elements. YY1-mediated enhancer-promoter interaction is the general feature of mammalian gene control. Recently, some computational methods have been developed to characterize the interactions between DNA elements by elucidating important features of chromatin folding; however, no computational methods have been developed for identifying the YY1-mediated chromatin loops. In this study, we developed a deep learning algorithm named DeepYY1 based on word2vec to determine whether a pair of YY1 motifs would form a loop. The proposed models showed a high prediction performance (AUCs$\ge$0.93) on both training datasets and testing datasets in different cell types, demonstrating that DeepYY1 has an excellent performance in the identification of the YY1-mediated chromatin loops. Our study also suggested that sequences play an important role in the formation of YY1-mediated chromatin loops. Furthermore, we briefly discussed the distribution of the replication origin site in the loops. Finally, a user-friendly web server was established, and it can be freely accessed at http://lin-group.cn/server/DeepYY1.


Assuntos
Cromatina/metabolismo , Bases de Dados Factuais , Aprendizado Profundo , Modelos Biológicos , Fator de Transcrição YY1/metabolismo , Células HCT116 , Humanos , Células K562
4.
Arch Biochem Biophys ; 735: 109502, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36603698

RESUMO

Necroptosis has been demonstrated to contribute to brain injury in ischemic stroke, whereas A20 can exert anti-necroptosis effect via deubiquitinating receptor-interacting protein kinase (RIPK3) at k63 and it can be cleaved by MALT1. This study aims to explore whether MALT1 is upregulated in the brain during ischemic stroke and promotes brain cell necroptosis through enhancing the degradation of A20. Ischemic stroke model was established in Sprague Dawley rats by occlusion of the middle cerebral artery (MCA) for 2 h, followed by 24 h reperfusion, which showed brain injury (increase in neurological deficit score and infarct volume) concomitant with an upregulation of MALT1, a decrease in A20 level, and increases in necroptosis-associated protein levels [RIPK3, mixed lineage kinase domain-like protein (MLKL) and p-MLKL] and k63-ubiquitination of RIPK3 in brain tissues. Administration of MALT1 inhibitor (Ml-2) at 8 or 15 mg/kg (i.p.) at 1 h after ischemia significantly improved neurological function and reduced infarct volume together with a downregulation of MALT1, an increase in A20 level and decreases in necroptosis-associated protein levels and k63-ubiquitination of RIPK3. Similarly, knockdown of MALT1 could also reduce oxygen-glucose deprivation/reoxygenation (OGD/R)-induced injury in the cultured HT22 cells coincident with an increase in A20 level and decreases in necroptosis-associated protein levels and k63-ubiquitination of RIPK3. Based on these observations, we conclude that MALT1 promotes necroptosis in stroke rat brain via enhancing the degradation of A20, which leads to a decrease in the capability of A20 to deubiquitinate RIPK3 at k63 and a subsequent compromise in counteraction against the brain cell necroptosis.


Assuntos
Lesões Encefálicas , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Ratos , Encéfalo/metabolismo , Lesões Encefálicas/metabolismo , Infarto/metabolismo , AVC Isquêmico/metabolismo , Ratos Sprague-Dawley , Acidente Vascular Cerebral/metabolismo , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/metabolismo
5.
Cardiovasc Drugs Ther ; 37(1): 9-23, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34495409

RESUMO

PURPOSE: Pellino3, an ubiquitin E3 ligase, prevents the formation of the death-induced signaling complex in response to TNF-α by targeting receptor-interacting protein kinase 1 (RIPK1), and bioinformatics analysis predicted an interaction between Pellino3 and caspofungin, a common antifungal drug used in clinics. This study aimed to explore the effect of caspofungin on brain injury in ischemic stroke and the underlying mechanisms. METHODS: Ischemic stroke injury was induced in Sprague Dawley rats by occlusion of the middle cerebral artery (MCA) for 2 h, followed by 24 h reperfusion. PC12 cells were deprived of both oxygen and glucose for 8 h and then were cultured for 24 h with oxygen and glucose to mimic an ischemic stroke in vitro. RESULTS: Animal experiments showed brain injury (increase in neurological deficit score and infarct volume) concomitant with a downregulation of Pellino3, a decreased ubiquitination of RIPK1, and an up-regulation of necroptosis-associated proteins [RIPK1, RIPK3, mixed lineage kinase domain-like protein (MLKL), p-RIPK1, p-RIPK3, and p-MLKL]. Administration of caspofungin (6 mg/kg, i.m.) at 1 h and 6 h after ischemia significantly improved neurological function, reduced infarct volume, up-regulated Pellino3 levels, increased RIPK1 ubiquitination, and down-regulated protein levels of RIPK1, p-RIPK1, p-RIPK3, and p-MLKL. PC12 cells deprived of oxygen/glucose developed signs of cellular injury (LDH release and necroptosis) concomitant with downregulation of Pellino3, decreased ubiquitination of RIPK1, and elevated necroptosis-associated proteins. These changes were reversed by overexpression of Pellino3. CONCLUSION: We conclude that Pellino3 has an important role in counteracting necroptosis via ubiquitination of RIPK1 and caspofungin can suppress the brain cell necroptosis in ischemic stroke through upregulation of Pellino3.


Assuntos
Lesões Encefálicas , AVC Isquêmico , Ratos , Animais , Regulação para Cima , Caspofungina/farmacologia , AVC Isquêmico/tratamento farmacológico , Ratos Sprague-Dawley , Necroptose , Encéfalo , Infarto , Oxigênio , Glucose/farmacologia , Apoptose
6.
Yi Chuan ; 45(8): 658-668, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37609817

RESUMO

P-TEFb, a heterodimer of the kinase CDK9 and Cyclin T1, is a critical regulator of promoter-proximal pause release of Pol II in metazoans. It is capable of forming three larger complexes, including the super elongation complex (SEC), the BRD4/P-TEFb complex and the 7SK snRNP. In the SEC or the BRD4/P-TEFb complex, P-TEFb is enzymatically active, while in the 7SK snRNP, its activity is inhibited. The SEC consists of AFF1 or 4, ENL or AF9, ELL1, 2 or 3 and EAF1 or 2 in addition to P-TEFb, the only subunit with catalytic activity, and the noncatalytic subunits have been found to be able to regulate pause release through P-TEFb. We and others recently found that AFF1, ENL and AF9 are capable of regulating transcriptional initiation, but it is unknown yet whether AFF4 is also capable of doing so. With respect to the gene regulation selectivity of the SEC and the BRD4/P-TEFb complex, one recent study showed that in human DLD-1 cells, the SEC only regulates pause release of heat shock (HS) genes, whereas the BRD4/P-TEFb complex regulates pause release of the rest of the genes. However, it is unclear whether those mechanisms are general. In this study for the purpose of further understanding the role of AFF4 in transcriptional regulation, we found that AFF4 knockdown by RNA interference in human HEL cells decreased not only cellular level but also global chromatin occupancy of CTD serine 2 phosphorylated Pol II. Direct target genes of AFF4 were identified by RNA-seq and CUT&Tag. Notably, we found by ChIP-seq and PRO-seq that AFF4 loss also increased promoter-proximal pause of Pol II on several hundred HS and thousands of non-HS genes. Mechanistically, AFF4 promotes pause release likely by facilitating the binding of P-TEFb to Pol II. These results suggest that extent of the impact of AFF4 on pause release is likely to be context-dependent or cell-type dependent.


Assuntos
Fator B de Elongação Transcricional Positiva , RNA Polimerase II , Humanos , RNA Polimerase II/genética , Fator B de Elongação Transcricional Positiva/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Ribonucleoproteínas Nucleares Pequenas , Fatores de Elongação da Transcrição , Proteínas de Ciclo Celular
7.
Brief Bioinform ; 21(3): 982-995, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31157855

RESUMO

5-Methylcytosine (m5C) plays an extremely important role in the basic biochemical process. With the great increase of identified m5C sites in a wide variety of organisms, their epigenetic roles become largely unknown. Hence, accurate identification of m5C site is a key step in understanding its biological functions. Over the past several years, more attentions have been paid on the identification of m5C sites in multiple species. In this work, we firstly summarized the current progresses in computational prediction of m5C sites and then constructed a more powerful and reliable model for identifying m5C sites. To train the model, we collected experimentally confirmed m5C data from Homo sapiens, Mus musculus, Saccharomyces cerevisiae and Arabidopsis thaliana, and compared the performances of different feature extraction methods and classification algorithms for optimizing prediction model. Based on the optimal model, a novel predictor called iRNA-m5C was developed for the recognition of m5C sites. Finally, we critically evaluated the performance of iRNA-m5C and compared it with existing methods. The result showed that iRNA-m5C could produce the best prediction performance. We hope that this paper could provide a guide on the computational identification of m5C site and also anticipate that the proposed iRNA-m5C will become a powerful tool for large scale identification of m5C sites.


Assuntos
5-Metilcitosina/metabolismo , Biologia Computacional/métodos , Algoritmos , Animais , Arabidopsis/metabolismo , Conjuntos de Dados como Assunto , Humanos , Camundongos , Saccharomyces cerevisiae/metabolismo
8.
BMC Pulm Med ; 22(1): 288, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35902819

RESUMO

BACKGROUND: Tuberculosis (TB) is a chronic infectious disease caused by the Mycobacterium tuberculosis complex (MTBC), which is the leading cause of death from infectious diseases. The rapid and accurate microbiological detection of the MTBC is crucial for the diagnosis and treatment of TB. Metagenomic next-generation sequencing (mNGS) has been shown to be a promising and satisfying application of detection in infectious diseases. However, relevant research about the difference in MTBC detection by mNGS between bronchoalveolar lavage fluid (BALF) and lung biopsy tissue specimens remains scarce. METHODS: We used mNGS to detect pathogens in BALF and lung biopsy tissue obtained by CT-guide percutaneous lung puncture (CPLP) or radial endobronchial ultrasound transbronchial lung biopsy (R-EBUS-TBLB) from 443 hospitalized patients in mainland China suspected of pulmonary infections between May 1, 2019 and October 31, 2021. Aim to evaluate the diagnostic performance of mNGS for detecting MTBC and explore differences in the microbial composition in the 2 specimen types. RESULTS: Among the 443 patients, 46 patients finally were diagnosed with TB, of which 36 patients were detected as MTBC positive by mNGS (8.93%). Striking differences were noticed in the higher detection efficiency of lung biopsy tissue compared with BALF (P = 0.004). There were no significant differences between the 2 specimen types in the relative abundance among the 27 pathogens detected by mNGS from the 36 patients. CONCLUSIONS: This study demonstrates that mNGS could offer an effective detection method of MTBC in BALF or lung tissue biopsy samples in patients suspected of TB infections. When it comes to the situations that BALF samples have limited value to catch pathogens for special lesion sites or the patients have contraindications to bronchoalveolar lavage (BAL) procedures, lung biopsy tissue is an optional specimen for MTBC detection by mNGS. However, whether lung tissue-mNGS is superior to BALF-mNGS in patients with MTBC infection requires further prospective multicenter randomized controlled studies with more cases.


Assuntos
Doenças Transmissíveis , Mycobacterium tuberculosis , Tuberculose , Biópsia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Pulmão/microbiologia , Mycobacterium tuberculosis/genética , Sensibilidade e Especificidade , Tuberculose/diagnóstico
9.
Int J Neurosci ; 132(6): 613-620, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33032501

RESUMO

OBJECTIVE: The cerebral ischemia-reperfusion (I/R) model is crucial for the study of cerebral stroke. Chrysophanol (Chry) can protect nerve damage of mice in cerebral ischemia-reperfusion injury. This study aimed at investigating the neuroprotective effects of chrysophanol through mitochondrial autophagy in mice with ischemia-reperfusion injury. MATERIALS AND METHODS: Adult mice were stochastically divided into five groups: sham, I/R (solvent), I/R+Chry (dose, 10.0ml/kg), I/R+Chry (dose, 1.0ml/kg), and I/R+Chry (dose, 0.1ml/kg). The cerebral ischemia-reperfusion model was made in I/R and I/R+Chry groups. The changes in hippocampal formation were observed by hematoxylin and eosin (H&E) staining. The expressions of LC3B-II and LC3B-I protein in hippocampus were demonstrated by western blot (WB). The fluorescence intensities of NIX, LC3B, and mitochondria were detected by immunohistochemistry fluorescent (IF). RESULTS: Comparing with the I/R group, the I/R+Chry groups showed improvements in reducing the damage on the hippocampus, indicated by the reduced ratio of LC3B-II and LC3B-I protein, decreased fluorescence intensity of NIX and LC3B, and increased intensity of mitochondrial fluorescence. CONCLUSION: Our study showed that chrysophanol may regulate mitochondrial autophagy through NIX protein and alleviate the damage of hippocampus through decreasing the level of mitochondrial autophagy.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Animais , Antraquinonas , Autofagia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto Cerebral , Hipocampo/metabolismo , Camundongos , Mitocôndrias/metabolismo , Reperfusão , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo
10.
BMC Med Educ ; 22(1): 512, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35773709

RESUMO

OBJECTIVE: To study the effect of the problem-based learning (PBL) method in ultrasonography (US) resident standardization training during the COVID-19 pandemic. METHODS: Fifty residents were divided into two groups to participate in a 30-day US training program. The residents in the observation group underwent PBL combined with the lecture-based learning (LBL) method, while the residents in the control group experienced the LBL method alone, with 25 residents in each group. A basic theoretical test, practical examination, and questionnaire were used to evaluate the teaching effect of the PBL + LBL method and the LBL method alone. RESULTS: The basic theoretical pretest score of the observation group was not significantly different from that of the control group. However, the posttest theoretical score and practical score were significantly higher in the observation group than in the control group (P < 0.01). The results of the questionnaire showed that the resident satisfaction level in the observation group with PBL combined with the LBL method was 96%, which was significantly higher than that of the control group with the LBL method alone (80%) (P < 0.05). CONCLUSION: The combination of PBL with the LBL method has obvious advantages over the LBL method alone in regard to the training of US residents during the COVID-19 pandemic.


Assuntos
COVID-19 , Aprendizagem Baseada em Problemas , Humanos , Pandemias , Aprendizagem Baseada em Problemas/métodos , Padrões de Referência , Ensino , Ultrassonografia
11.
J Asthma ; 58(3): 326-333, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-31820665

RESUMO

OBJECTIVE: To evaluate the diagnostic value of fractional exhaled nitric oxide (FeNO) and maximum mid-expiratory flow (MMEF) for differentiating cough variant asthma (CVA) from chronic cough in patients with or without allergic rhinitis. METHODS: In total, 328 patients with chronic cough who underwent spirometry and FeNO testing were consecutively included in the retrospective analysis. Patients were divided into the CVA (n = 125) or NCVA (n = 203) groups according to the diagnostic criteria of CVA. Receiver operating characteristic (ROC) curves were established to assess the diagnostic efficiency and optimal cutoff points of FeNO and MMEF for the prediction of CVA. RESULTS: The optimal cutoff values of FeNO and MMEF to discriminate CVA from chronic cough were 24.5 ppb (AUC, 0.765; sensitivity, 69.60%; specificity 72.91%; PPV, 61.27%; NPV, 79.57%) and 66.2% (AUC, 0.771; sensitivity, 67.20%; specificity 78.33%; PPV, 65.63%; NPV, 79.50%). The optimal cutoff values of combining FeNO with MMEF to discriminate CVA from chronic cough were >22 ppb for FeNO and <62.6% for MMEF (AUC, 0.877). In patients with and without allergic rhinitis, the optimal cutoff point of FeNO to discriminate CVA from chronic cough was 24.5 ppb (AUC, 0.820) and 33.5 ppb (AUC, 0.707), respectively. CONCLUSIONS: FeNO and MMEF might have greater value as negative parameters for differentiating CVA from chronic cough. Combining FeNO and MMEF provided a significantly better prediction than either alone. The diagnostic accuracy of FeNO for predicting CVA in chronic cough patients with allergic rhinitis was higher than in chronic cough patients without allergic rhinitis.


Assuntos
Asma/diagnóstico , Asma/fisiopatologia , Tosse/diagnóstico , Tosse/fisiopatologia , Testes de Função Respiratória/métodos , Rinite Alérgica/fisiopatologia , Adolescente , Adulto , Idoso , Asma/classificação , Asma/epidemiologia , Tosse/epidemiologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/análise , Curva ROC , Valores de Referência , Estudos Retrospectivos , Rinite Alérgica/epidemiologia , Adulto Jovem
12.
Curr Genomics ; 21(1): 11-25, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32655294

RESUMO

MicroRNAs, a group of short non-coding RNA molecules, could regulate gene expression. Many diseases are associated with abnormal expression of miRNAs. Therefore, accurate identification of miRNA precursors is necessary. In the past 10 years, experimental methods, comparative genomics methods, and artificial intelligence methods have been used to identify pre-miRNAs. However, experimental methods and comparative genomics methods have their disadvantages, such as time-consuming. In contrast, machine learning-based method is a better choice. Therefore, the review summarizes the current advances in pre-miRNA recognition based on computational methods, including the construction of benchmark datasets, feature extraction methods, prediction algorithms, and the results of the models. And we also provide valid information about the predictors currently available. Finally, we give the future perspectives on the identification of pre-miRNAs. The review provides scholars with a whole background of pre-miRNA identification by using machine learning methods, which can help researchers have a clear understanding of progress of the research in this field.

13.
Zhongguo Zhong Yao Za Zhi ; 45(9): 2115-2121, 2020 May.
Artigo em Zh | MEDLINE | ID: mdl-32495560

RESUMO

A rapid analysis method based on ultraviolet-visual(UV-Vis) spectroscopy, near infrared(NIR) spectroscopy and multivariable data analysis was established for quality evaluation of Shengxuebao Mixture. The contents of eight active ingredients of Shengxuebao Mixture including albiflorin, paeoniflorin, 2, 3, 5, 4'-tetra-hydroxy-stilbene-2-O-ß-D-glucopyranoside, specnuezhenide,ecliptasaponin D, emodin, calycosin-7-glucoside and astragaloside Ⅳ were simultaneously detected by using this method. HPLC-UV-MS was used as a reference method for determining the contents of these ingredients. Partial least squares(PLS) analysis was implemented as a linear method for multivariate models calibrated between UV spectrum/NIR spectrum and contents of 8 ingredients. Finally, the performance of the model was evaluated by 24 batches of test samples. The results showed that both UV-Vis and NIR models gave a good calibration ability with an R~2 value above 0.9, and the prediction ability was also satisfactory, with an R~2 value higher than 0.83 for UV-Vis model and higher than 0.79 for NIR model. The overall results demonstrate that the established method is accurate, robust and fast, therefore, it can be used for rapid quality evaluation of Shengxuebao Mixture.


Assuntos
Medicamentos de Ervas Chinesas , Espectroscopia de Luz Próxima ao Infravermelho , Calibragem , Cromatografia Líquida de Alta Pressão , Análise dos Mínimos Quadrados , Espectrometria de Massas
14.
Nanomedicine ; 21: 102047, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31271877

RESUMO

Drug delivery nanocarriers based on magnetic nanoparticles have attracted increasing attention due to their potential applications in magnetic resonance imaging, photodynamic therapy and targeted drug delivery. Herein, we have fabricated the multifunctional co-loaded magnetic nanocapsules (MNCPs) using a microemulsion process for enhancing targeted magnetic resonance imaging and in vivo photodynamic therapy. MNCPs were synthesized by co-loading Co@Mn magnetic nanoparticles and chlorin e6 into the matrix of an amphiphilic polymer, and further surface covalently coupled with target molecules. This work demonstrates that MNCPs have uniform sizes (dc: ~150 nm), favorable biocompatibility, long-term stability, excellent T2 relaxation values, and high drug loading efficiency. These advantages offer MNCPs successfully applied in targeted magnetic resonance imaging, real-time fluorescent labeling, and photodynamic therapy. The research results will contribute to rationally design novel nano-platform and provide a promising approach for further clinical integration of diagnosis and treatment in the near future.


Assuntos
Materiais Biocompatíveis/farmacologia , Sistemas de Liberação de Medicamentos , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/química , Materiais Biocompatíveis/química , Clorofilídeos , Cobalto/química , Cobalto/farmacologia , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Humanos , Manganês/química , Manganês/farmacologia , Fotoquimioterapia/métodos , Porfirinas/química , Porfirinas/farmacologia
15.
Zhongguo Zhong Yao Za Zhi ; 43(21): 4248-4254, 2018 Nov.
Artigo em Zh | MEDLINE | ID: mdl-30583625

RESUMO

In this study, the HPLC-UV-MS method for the simultaneous determination of eight active ingredients of Shengxuebao Mixture were developed based on the concept of quality by design(QbD)with a stepwise optimization approach. After the analytical target profile(ATP)had been defined, albiflorin, paeoniflorin, 2, 3, 5, 4'-tetra-hydroxy-stilbene-2-O-ß-D-glucopyranoside, specnuezhenide, ecliptasaponin D, emodin, calycosin-7-glucoside, and astragaloside Ⅳ were identified as the indicator components. The resolution and the signal-to-noise ratio of indicator components were then selected as critical method attributes (CMA) for the first step optimization. According to the results collected from fractional factorial design, critical method parameters (CMP) were determined with a multiple linear regression method, which included the amount of acid addition in the mobile phase, temperature, gradient, and wavelength. After that, the amount of acid addition and the wavelength were optimized to improve the resolution and the signal-to-noise ratio of the indicator components. The peak symmetry factors of specnuezhenide and emodin were then set as CMA for the second step optimization. The Box-Behnken designed experiments were conducted. The temperature and gradient were optimized after modelling. The design space were calculated and verified. The optimized analytical method was validated, and the results showed a good precision, accuracy and stability, which means that it can be used for the quantification of the indicator components in Shengxuebao Mixture.


Assuntos
Medicamentos de Ervas Chinesas/análise , Compostos Fitoquímicos/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Reprodutibilidade dos Testes
16.
J Am Chem Soc ; 138(23): 7212-5, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27219078

RESUMO

Carbene-catalyzed reaction of carboxylic esters has the potential to offer effective synthetic solutions that cannot be readily achieved by using the more conventional aldehyde-type substrates. Here we report the first carbene-catalyzed dynamic kinetic resolution of α,α-disubstituted carboxylic esters with up to 99:1 er and 99% yield. The present study clearly illustrates the unique power of carbene-catalyzed reactions of readily available and easy to handle carboxylic esters.

17.
Bioorg Med Chem Lett ; 26(19): 4720-4723, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27575480

RESUMO

Strontium fructose 1,6-diphosphate (FDP-Sr) is a new strontium-containing compound. The primary aim of this study was to clarify whether the structure component of FDP-Sr, FDP could benefit the protective effect of Sr (II) against oxidative stress induced apoptosis, and meanwhile to further explore the important role of Wnt/ß-catenin signaling in the anti-apoptosis effect of FDP-Sr in response to oxidative stress induced by H2O2 in an osteoblastic MC3T3-E1 cell line. Results showed that FDP-Sr could improve the osteoblastic differentiation under oxidative stress with induced cell proliferation and improved mineralization. The inhibition effect of FDP-Sr on cell apoptosis induced by H2O2 was proved by reduced reactive oxygen species production and activated caspase3. Under oxidative stress, mRNA and protein levels of phospho-ß-catenin reduced, while ß-catenin increased in the FDP-Sr treatment cell, leaded to the up-regulations of Runx2 and OPG at both mRNA and protein levels, finally improved the differentiation of osteoblasts. By the engagement of Wnt/ß-catenin pathway's inhibitor (XAV-939), the protective effects of FDP-Sr on osteoblastic differentiation against oxidative stress were repressed along with inhibited wnt/ß-catenin signaling and reduced mRNA and protein levels of Runx2 and OPG. In conclusion, FDP-Sr was demonstrated to protect osteoblast differentiation from oxidative damage induced by H2O2 through up-regulation of Wnt/ß-catenin signaling, and FDP in FDP-Sr was able to directly improve the oxidative stress injury through its ROS scavenging ability.


Assuntos
Formicinas/química , Estresse Oxidativo/efeitos dos fármacos , Ribonucleotídeos/química , Transdução de Sinais , Proteínas Wnt/metabolismo , Células 3T3 , Animais , Camundongos
18.
J Oral Maxillofac Surg ; 74(11): 2193-2199, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27235180

RESUMO

PURPOSE: Periorbital infantile hemangiomas (IHs) require early intervention because they have the potential risk of causing visual disturbances. In recent years, propranolol has shown promise in the effective management of periocular and periorbital IHs. The objective of our study was to assess the clinical outcomes, efficacy, and safety of propranolol in the management of infants with high-risk periorbital IHs. PATIENTS AND METHODS: This retrospective study was conducted at the Stomatological Hospital affiliated with China Medical University. The medical records of infants with periorbital hemangiomas who were treated with systemic propranolol at a dose of 1.0 to 1.5 mg/kg per day between January 2014 and June 2015 were reviewed. We excluded infants who did not qualify for propranolol treatment and infants who received previous therapy or other treatments. The records were reviewed for treatment response, adverse events during treatment, length of treatment, and recurrences. Treatment response was classified using a 4-point scale system based on reduction in volume as poor (<25%), moderate (25 to 50%), good (50 to 75%), or excellent (>75 to 100%) and change in color, as well as surface texture, by a panel of 3 plastic surgeons using 2-dimensional photographs, clinical examination, and Doppler ultrasonography measurements taken before and after treatment. RESULTS: Of 38 infants with periorbital hemangiomas, 26 were treated with systemic propranolol at a dose of 1.0 to 1.5 mg/kg administered once daily. A total of 11 male and 15 female infants with a mean age of 5.2 months (range, 2 to 12 months) were treated. The mean length of treatment was 22 weeks (range, 4 to 41 weeks). Adverse events of diarrhea (n = 3) and sleep changes (n = 1) were encountered during treatment in 4 patients. The overall treatment response was scored as excellent in 17 patients, good in 7, moderate in 2, and poor in 0. No patients required discontinuation of treatment because of adverse events, and there were no cases of recurrence or tumor regrowth noted during the mean follow-up period of 6.5 months (range, 3 to 10 months). CONCLUSIONS: Oral propranolol at a dose of 1.0 to 1.5 mg/kg per day (age ≤3 months, 1.0 mg/kg; age >3 months, 1.5 mg/kg) was effective and well tolerated for the management of 26 Chinese infants with high-risk periorbital IHs. Early intervention should be considered to reduce risk of visual impairment and improve esthetic outcomes.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Hemangioma/tratamento farmacológico , Propranolol/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Administração Oral , Esquema de Medicação , Olho , Feminino , Seguimentos , Humanos , Lactente , Masculino , Estudos Retrospectivos , Resultado do Tratamento
19.
J Oral Maxillofac Surg ; 74(8): 1623-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27055227

RESUMO

PURPOSE: Infantile hemangiomas (IHs) are the most common benign tumors affecting infants, and most IHs are self-limiting. However, there are cases that require specific treatment. Propranolol is now widely used to treat severe IHs. Several studies have shown the efficacy and limited side effects associated with propranolol as the first-line treatment for IHs. There are a limited number of publications describing the role of propranolol in treating IHs beyond the proliferative phase (>12 months). The purpose of this study was to evaluate the effects and safety of oral high-dose (2.0 mg/kg per day) propranolol for IHs beyond the proliferative phase (>12 months). PATIENTS AND METHODS: This study enrolled patients with IHs who accepted systemic propranolol treatment from the Department of Oral and Maxillofacial Surgery, Stomatological Hospital Affiliated China Medical University. This is a single-center retrospective study conducted from April 2011 to July 2015. All children who were older than 12 months were eligible for the study. Digital photographs taken before and after treatment were analyzed by a panel of 3 plastic surgeons. The esthetic results were evaluated using a 4-point scale and ranked as poor, moderate, good, or excellent. The patient follow-up visits were scheduled monthly, and changes in the size, texture, and color of the lesions were recorded. The adverse effects after medication were evaluated and managed accordingly. RESULTS: We collected data on 31 eligible patients. The 31 patients had 32 hemangiomas (1 female patient had 2 lesions) and were treated with systemic propranolol at a high dose of 2 mg/kg per day. The mean age at the initiation of propranolol therapy was 18.4 months (range, 12 to 48 months), and the mean treatment duration was 10.1 months (range, 8 to 16 months). The treatment responses for the 32 hemangiomas included 17 excellent responses (53.1%), 8 good responses (25%), and 7 moderate responses (21.9%). There were no severe side effects encountered and recurrence was observed in 3 patients during the treatment and follow-up course. CONCLUSIONS: Oral propranolol, 2 mg/kg per day, is a safe and effective treatment for IHs beyond the proliferative phase (>12 months of age) in the Chinese population.


Assuntos
Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Hemangioma/tratamento farmacológico , Propranolol/uso terapêutico , Vasodilatadores/uso terapêutico , Administração Oral , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Propranolol/administração & dosagem , Estudos Retrospectivos , Vasodilatadores/administração & dosagem
20.
J Craniofac Surg ; 27(2): 509-15, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26890455

RESUMO

The objective of the study was to discuss the biocompatibility of the vascular endothelial growth factor-silk fibroin-chitosan (VEGF-SF-CS) scaffolds. To offer an ideal scaffold for bone tissue engineering, the author added vascular endothelial growth factor (VEGF) into silk fibroin-chitosan (SF-CS) scaffold directly to reconstruct a three-dimensional scaffold for the first time, SF-CS scaffold was loaded with VEGF and evaluated as a growth factor-delivery device. Human fetal osteoblast cell was seeded on the VEGF-SF-CS scaffolds and SF-CS scaffolds. On VEGF-SF-CS and SF-CS scaffolds, the cell adhesion rate was increased as time went on. Scanning electron microscopy: the cells grew actively and had normal multiple fissions, granular and filamentous substrates could be seen around the cells, and cell microfilaments were closely connected with the scaffolds. The cells could not only show the attached growth on surfaces of the scaffolds, but also extend into the scaffolds. Cell Counting Kit-8 and alkaline phosphatase analysis proved that the VEGF could significantly promote human fetal osteoblast1.19 cells growth and proliferation in the SF-CS scaffolds, but the enhancement of osteoblasts cell proliferation and activity by VEGF was dependent on time.


Assuntos
Quitosana/química , Fibroínas/química , Osteogênese/fisiologia , Seda/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Fator A de Crescimento do Endotélio Vascular/química , Citoesqueleto de Actina/fisiologia , Citoesqueleto de Actina/ultraestrutura , Fosfatase Alcalina/análise , Materiais Biocompatíveis/química , Adesão Celular/fisiologia , Contagem de Células , Técnicas de Cultura de Células , Proliferação de Células , Forma Celular/fisiologia , Células Cultivadas , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteoblastos/fisiologia , Osteoblastos/ultraestrutura , Propriedades de Superfície
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