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1.
Vaccines (Basel) ; 11(12)2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-38140149

RESUMEN

There are some concerns about the safety of live attenuated yellow fever vaccines (YF-live), particularly viscerotropic adverse events, which have a high mortality rate. The cellular production of the vaccine will not cause these adverse effects and has the potential to extend applicability to those who have allergic reactions, immunosuppression, and age. In this study, inactivated yellow fever (YF) was prepared and adsorbed with Alum/CpG. The cellular and humoral immunities were investigated in a mouse model. The results showed that Alum/CpG (20 µg/mL) could significantly increase the binding and neutralizing activities of the antibodies against YF. Moreover, the antibody level at day 28 after one dose was similar to that of the attenuated vaccine, but significantly higher after two doses. At the same time, Alum/CpG significantly increased the levels of IFN-γ and IL-4 cytokines.

2.
Micromachines (Basel) ; 14(11)2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-38004855

RESUMEN

This study presents an investigation focusing on the advancement of a robot designed for subretinal injections in the context of macular degeneration treatment. The technique of subretinal injection surgery stands as the most efficacious approach for the successful transplantation of stem cells into the retinal pigment epithelium layer. This particular procedure holds immense significance in advancing research and implementing therapeutic strategies involving retinal stem cell transplantation. The execution of artificial subretinal surgery poses considerable challenges which can be effectively addressed through the utilization of subretinal injection surgery robots. The development process involved a comprehensive modeling phase, integrating computer-aided design (CAD) and finite element analysis (FEA) techniques. These simulations facilitated iterative enhancements of the mechanical aspects pertaining to the robotic arm. Furthermore, MATLAB was employed to simulate and visualize the robot's workspace, and independent verification was conducted to ascertain the range of motion for each degree of freedom.

3.
Front Public Health ; 11: 1201162, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37780444

RESUMEN

Objective: Maternal syphilis could cause serious consequences. The aim of this study was to identify risk factors for maternal syphilis in order to predict an individual's risk of developing adverse pregnancy outcomes (APOs). Methods: A retrospective study was conducted on 768 pregnant women with syphilis. A questionnaire was completed and data analyzed. The data was divided into a training set and a testing set. Using logistic regression to establish predictive models in the training set, and its predictive performance was evaluated in the testing set. The probability of APOs occurrence is presented through a nomogram. Results: Compared with the APOs group, pregnant women in the non-APOs group participated in a longer treatment course. Course, time of the first antenatal care, gestation week at syphilis diagnosis, and gestation age at delivery in weeks were independent predictors of APOs, and they were used to establish the nomogram. Conclusions: Our study investigated the impact of various characteristics of syphilis pregnant women on pregnancy outcomes and established a prediction model of APOs in Suzhou. The incidence of APOs can be reduced by controlling for these risk factors.


Asunto(s)
Complicaciones Infecciosas del Embarazo , Sífilis , Embarazo , Femenino , Humanos , Resultado del Embarazo/epidemiología , Sífilis/epidemiología , Estudios Retrospectivos , Modelos Logísticos , Complicaciones Infecciosas del Embarazo/epidemiología , Factores de Riesgo
4.
Int J Mol Sci ; 24(20)2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37894895

RESUMEN

Tetrahydroprotoberberines (THPBs) are plant-specific alkaloids with significant medicinal value. They are present in trace amounts in plants and are difficult to chemically synthesize due to stereoselectivity and an unfavorable environment. In this study, a selective methylation strategy was developed for the biocatalysis of seven high-value-added THPB compounds using 4'-O-methyltransferase (Cj4'OMT), norcoclaurine 6-O-methyltransferase (Cj6OMT), and (S)-scoulerine 9-O-methyltransferase (SiSOMT and PsSOMT) in engineered E. coli. The methyltransferases Cj4'OMT, Cj6OMT, PsSOMT, and SiSOMT were expressed heterologously in E. coli. Compound 1 (10-methoxy-2,3,9-tetrahydroxyberbine) was synthesized using the recombinant E. coli strain Cj4'OMT and the substrate 2,3,9,10-tetrahydroxyberbine. Compound 2 (9-methoxy-2,3,10-tetrahydroxyberbine) was produced in the recombinant Escherichia coli (E. coli) strain PsSOMT, and compounds 2 and 3 (discretamine) were produced in the recombinant E. coli strain SiSOMT. Compounds 4 (9,10-methoxy-2,3-tetrahydroxyberbine) and 5 (corypalmine) were obtained by co-culturing the recombinant strains Cj4'OMT and SiSOMT with substrate. Compounds 6 (scoulerine) and 7 (isoscoulerine) were produced by co-culturing the substrate with the recombinant strains Cj4'OMT and Cj6OMT. To increase the yield of novel compound 2, the flask culture conditions of the engineered SiSOMT strain were optimized, resulting in the production of 165.74 mg/L of this compound. This study thus presents an enzymatic approach to the synthesis of high-value-added THPBs with minimum environmental wastage.


Asunto(s)
Alcaloides , Escherichia coli , Metilación , Escherichia coli/genética , Escherichia coli/metabolismo , Metiltransferasas/metabolismo , Procesamiento Proteico-Postraduccional
5.
Adv Mater ; 35(35): e2302685, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37358298

RESUMEN

Smart windows nowadays undertake the esteemed obligation of reducing energy consumption as well as upgrading living experience. This project aims to devise a smart window that responds to both electricity and heat, with the intention of achieving energy efficiency, privacy preservation, and enhanced decorative attributes. Through the implementation of a novel electrochromic material design, coupled with the optimization of electrochromic devices (ECDs), a high-performance ECD is obtained, demonstrating coloring/bleaching time of 0.53/0.16 s, a transmittance modulation of 78% (from 99% to 21%), and superior performance in six dimensions. Furthermore, temperature-responsive units and an ionic liquid are incorporated into the electrolyte system to create a novel thermochromic gel electrolyte with transmittance modulation from 80% to 0%, and excellent thermal insulation (6.4 °C reduction). Ultimately, an electro- and thermochromic device is developed, featuring an ultrafast color-switching speed of 0.82/0.60 s and multiple working modes. Overall, this work showcases a prospective design pathway for the development of next-generation ultrafast-switching, and energy-efficient intelligent windows.

6.
Front Plant Sci ; 14: 1176293, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37324671

RESUMEN

Increasing nitrogen (N) input is essential to satisfy the rising global wheat demand, but this increases nitrous oxide (N2O) emissions, thereby exacerbating global climate change. Higher yields accompanied by reduced N2O emissions are essential to synergistically reduce greenhouse warming and ensure global food security. In this study, we conducted a trial using two sowing patterns (conventional drilling sowing [CD] and wide belt sowing [WB], with seedling belt widths of 2-3 and 8-10 cm, respectively) with four N rates (0, 168, 240, and 312 kg ha-1, hereafter N0, N168, N240, and N312, respectively) during the 2019-2020 and 2020-2021 growing seasons. We investigated the impacts of growing season, sowing pattern, and N rate on N2O emissions, N2O emissions factors (EFs), global warming potential (GWP), yield-scaled N2O emissions, grain yield, N use efficiency (NUE), plant N uptake and soil inorganic N concentrations at jointing, anthesis, and maturity. The results showed that sowing pattern and N rate interactions influenced the N2O emissions markedly. Compared to CD, WB significantly reduced cumulative N2O emissions, N2O EFs, GWP, and yield-scaled N2O emissions for N168, N240, and N312, with the largest reduction seen at N312. Furthermore, WB markedly improved plant N uptake and reduced soil inorganic N compared to CD at each N rate. Correlation analyses indicated that WB mitigated the N2O emissions at various N rates mainly through efficient N uptake and reduced soil inorganic N. The highest grain yield occurred under a combination of WB and N312, under which the yield-scaled N2O emissions were equal to the local management (sowing with CD at N240). In conclusion, WB sowing could synergistically decrease N2O emissions and obtain high grain yields and NUEs, especially at higher N rates.

7.
Adv Mater ; 35(22): e2211617, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36921620

RESUMEN

Hydrogels have entered the spotlight for applications in soft electronics. It is essential and challenging to obtain hydrogels that can function properly under varying environmental circumstances, that is, 30-90% relative humidity (RH) and -20 to 40 °C due to their intrinsic nature to lose and absorb water upon variations in humidity and temperature. In this work, a green solvent, solketal, is introduced into poly 3-dimethyl-2-(2-methylprop-2-enoyloxy)ethyl azaniumyl propane-1-sulfonate (poly(DMAPS)) zwitterionic hydrogels. Compared to glycerol, solketal endows hydrogels with greater possibility for further modification as well as improved water content and mechanical performance consistency over 30-90% RH. Encouragingly, the optimized hydrogel demonstrates its unique merits as a dielectric layer in iontronic sensors, featuring non-leaky ions, high sensitivity (1100 kPa-1 ), wide humidity, and temperature range applicability. A wide-humidity range healable and stretchable electrode is attained by combining the hydrogel substrate with Ag paste. A full-device healable and highly-sensitive sensor is developed. This study is a pioneering work that tackles the broad humidity range applicability issue of hydrogels, and demonstrates the ion-leakage-free ionic skins with zwitterionic dielectrics. The outcomes of the study will considerably promote advancements in the fields of hydrogel electronics and iontronic sensors.

8.
J Agric Food Chem ; 70(17): 5357-5368, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35442674

RESUMEN

An excessive nitrogen (N) supply may weaken dough due to an imbalance between N and sulfur (S) in the grains. However, the mechanism underlying the weakening effect of excessive N supply has yet to be fully elucidated. In this study, we evaluated the effect of the N rate × S rate interaction on the ratio of N to S (N/S ratio), grain protein concentration, amount and composition of protein fractions, and dough properties of a bread wheat cultivar. The concentrations of glutathione and modified gliadins with an odd number of cysteine residues (potential chain terminators for glutenins) were also examined. The results revealed that the weakening effect of excess N input is closely associated with an increased gliadin/glutenin ratio, reduced low-molecular-weight glutenin subunit concentrations, and the degree of polymerization of glutenin. More importantly, we found that the increased concentrations of glutathione and chain terminators in grains are involved in the modification of the polymerization degree in glutenins.


Asunto(s)
Nitrógeno , Triticum , Pan , Harina , Gliadina/metabolismo , Glutatión/metabolismo , Glútenes/química , Nitrógeno/metabolismo , Triticum/química
9.
Exp Ther Med ; 23(3): 204, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35126707

RESUMEN

The melanoma antigen gene family A (MAGEA) family of proteins comprises of cancer-testis antigens that are highly expressed in a number of tumours but are minimally expressed in normal cells. Due to its expression characteristics, this protein family has become a popular target for anti-cancer drugs and immunotherapy research over recent years. Although, elevated expression levels of MAGEA6 has been found in different types of tumours, there remains to be insufficient information on the function of MAGEA6 and its associated gene regulation pathways. The present study used Transwell, Cell Counting Kit-8 and wound healing assays to analyse the effects of MAGEA6 on Eca109 cell invasion, migration and proliferation. The main functions and pathways involved in MAGEA6 were predicted by Illumina Hiseq screening for mutually regulated genes and core genes. Eca109 cell line with a high expression of MAGEA6 was a stable cell line obtained by transfection in the early stage, and this cell line was used in subsequent experiments. Transcriptome sequencing was performed on this cell line and the Eca109 cell line that normally expressed MAGEA6. It was revealed that a high expression of MAGEA6 conferred a significant stimulating effect on cell proliferation whilst also significantly increasing cell invasion and migration. Transcriptomic analysis identified 14 differentially expressed genes and 13 core regulatory genes closely associated with MAGEA6 expression regulation, such as methylsterol monooxygenase 1 (MSMO1). The present study suggest that MAGEA6 positively regulated MSMO1 expression, which may serve an oncogenic role in cells through this regulatory effect. Overall, this provided a novel route of investigation for an in-depth study of the regulatory function of MAGEA6.

10.
Biochem Biophys Res Commun ; 579: 1-7, 2021 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-34571387

RESUMEN

Chronic myeloid leukemia (CML) is a hematologic malignancy originating from BCR-ABL oncogene-transformed hematopoietic stem cells (HSCs) known as leukemia stem cells (LSCs). Therefore, targeting LSCs is of primary importance to eradicate CML. The present study demonstrates that picropodophyllin (PPP) effectively induces apoptosis and inhibits colony formation in CML stem/progenitor cells as well as quiescent CML progenitors resistant to imatinib therapy, while sparing normal hematopoietic cells in vitro. Administration of PPP in vivo markedly diminishes CML stem/progenitor cells in a transgenic mouse model of CML by inhibition of cell proliferation and enhancement of apoptosis in LSK cells, and significantly improves survival of CML mice. Furthermore, PPP treatment preferentially leads to transcriptional activation of p53 in CML but not normal CD34+ cells, upregulation of p53 protein in LSCs-enriched Sca-1+ cells from CML mice, and increased phosphorylation of p53 and upregulation of Bax protein in Ku812 cells. These results suggest that the inhibitory effects of PPP on CML stem/progenitor cells are associated with selective activation of p53 pathway and propose that PPP is a potent agent that selectively targets CML LSCs, and may be of value in the CML therapy.


Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Células Madre Neoplásicas/efectos de los fármacos , Podofilotoxina/análogos & derivados , Células Madre/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Animales , Antígenos CD34/biosíntesis , Apoptosis , Modelos Animales de Enfermedad , Sangre Fetal/metabolismo , Proteínas de Fusión bcr-abl/metabolismo , Humanos , Técnicas In Vitro , Células K562 , Ratones , Ratones Transgénicos , Microtúbulos/metabolismo , Fosforilación , Podofilotoxina/química , Transducción de Señal , Activación Transcripcional
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(2): 395-402, 2021 Apr.
Artículo en Chino | MEDLINE | ID: mdl-33812405

RESUMEN

OBJECTIVE: To investigate the effect of etoposide (ETO) on elimination of chronic myeloid leukemia (CML) stem cells by imatinib mesylate(IM) in vivo. METHODS: SCL-tTA/BCR-ABL mice were used as CML animal model. Flow cytometry was used to assess the effect of ETO alone or in combination with IM on the number of leukemia stem cell (LSC) in bone marrow and spleen, and peripheral blood neutrophils in CML mice and normal control FVB mice. RESULTS: The results showed that in CML mice, the number and proportion of LSC in bone marrow and the proportion of neutrophils in peripheral blood decreased significantly after ETO and IM combined treatment, and the degree of decrease was more significant than that of both alone. While in wild type FVB mice, the combination of ETO and IM showed no significant effect on the number and proportion of LSK cells in bone marrow and the proportion of neutrophils in spleen. CONCLUSION: ETO can selectively enhance elimination of CML LSC by IM in vivo.


Asunto(s)
Resistencia a Antineoplásicos , Leucemia Mielógena Crónica BCR-ABL Positiva , Animales , Etopósido , Proteínas de Fusión bcr-abl , Mesilato de Imatinib , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Ratones , Células Madre
12.
Fitoterapia ; 141: 104453, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31857178

RESUMEN

Stephania species is one of the alkaloid-rich genus of the family Menispermaceae. Most plants of the genus Stephania possess medicinal value, whose main components are alkaloids. However, the non-medical species are often mistakenly used as herbs because of the difficulty in identification of the species. A systematic method which involved the combination of DNA barcoding, HPLC-QTOF-MS/MS and UHPLC was established for differentiation, chemical profiles and quality evaluation of medicinal Stephania species. Firstly, twenty batches of Stephania species samples were classified into five Stephania species by DNA barcoding. Secondly, 114 alkaloids including 22 tetrahydroprotoberberines, 13 protoberberines, 27 aporphines, 13 benzylisoquinolines, 12 hasubanans, 3 morphines and 24 other alkaloids were clearly or tentatively identified. Thirdly, thirteen representative components were simultaneously detected by UHPLC-DAD to characterize the differences of chemical compositions among five Stephania species. In conclusion, this method was comprehensive and effective for identification, chemical profiles and quality evaluation of medicinal Stephania species. It will provide a basis for holistic quality evaluation of medicinal Stephania species.


Asunto(s)
Cromatografía Liquida/métodos , Código de Barras del ADN Taxonómico , ADN de Plantas/genética , Stephania/química , Espectrometría de Masas en Tándem/métodos , Alcaloides/química , Alcaloides/metabolismo , ADN Intergénico , Variación Genética , Humanos , Raíces de Plantas , Tallos de la Planta , Especificidad de la Especie
13.
Biotechnol Lett ; 42(3): 461-469, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31865477

RESUMEN

OBJECTIVES: To characterize methyltransferases involved in the biosynthesis of benzylisoquinoline alkaloids in Stephania intermedia. RESULTS: Three N-methyltransferases, SiCNMT1, SiCNMT2, SiCNMT3, and O-methyltransferase SiSOMT were identified in Stephania intermedia. Then, four methyltransferase genes were cloned into the pGEX-6P-1 vector. The recombinant vectors were transformed into Escherichia coli BL21(DE3) for expression and were functionally tested. SiCNMT1, SiCNMT2, and SiCNMT3 could methylate (R)-coclaurine to produce (R)-N-methylcoclaurine. SiCNMT2 further methylated the product of (R)-N-methylcoclaurine to produce (R)-magnocurarine. Similarly, (R)-norcoclaurine was continuously catalyzed to yield (R)-N-methylnorcoclaurine and (R)-N, N-dimethylnorcoclaurine by SiCNMT2. Furthermore, SiSOMT was shown to catalyze the conversion of (S)-scoulerine to (S)-tetrahydropalmatine. CONCLUSIONS: The key methyltransferases, which were in the last step biosynthesis of (R)-magnocurarine, (R)-N, N-dimethylnorcoclaurine and (S)-tetrahydropalmatine were revealed and their activities were verified in vitro. Four novel methyltransferases will be promising candidates for methylation of benzylisoquinoline alkaloids.


Asunto(s)
Bencilisoquinolinas/química , Metiltransferasas/química , Proteínas de Plantas/química , Stephania/enzimología , Bencilisoquinolinas/metabolismo , Clonación Molecular , Metiltransferasas/biosíntesis , Metiltransferasas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Stephania/genética
14.
Cell Biol Int ; 41(1): 16-23, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27677634

RESUMEN

Imatinib mesylate (IM) and other BCR-ABL tyrosine kinase inhibitors (TKIs) have improved chronic myeloid leukemia (CML) patient survival markedly but fail to eradicate quiescent CML leukemia stem cells (LSCs). Thus, strategies targeting LSCs are required to induce long-term remission and achieve cure. Here, we investigated the ability of topoisomerase II (Top II) inhibitor etoposide (Eto) to target CML LSCs. Treatment with Eto combined with IM markedly induced apoptosis in primitive CML CD34+ CD38- stem cells resistant to eradication by IM alone, but not in normal hematopoietic stem cells, CML and normal mature CD34- cells, and other leukemia and lymphoma cell lines. The interaction of IM and Eto significantly inhibited phosphorylation of PDK1, AKT, GSK3, S6, and ERK proteins; increased the expression of pro-apoptotic gene Bax; and decreased the expression of anti-apoptotic gene c-Myc in CML CD34+ cells. Top II inhibitors treatment represents an attractive approach for targeting LSCs in CML patients undergoing TKIs monotherapy.


Asunto(s)
Etopósido/farmacología , Mesilato de Imatinib/farmacología , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Células Madre Neoplásicas/patología , Inhibidores de Topoisomerasa II/farmacología , Antígenos CD34/metabolismo , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Etopósido/uso terapéutico , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Humanos , Mesilato de Imatinib/uso terapéutico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Ensayo de Tumor de Célula Madre
15.
Leuk Res ; 39(10): 1117-24, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26248946

RESUMEN

BCR-ABL tyrosine kinase inhibitor imatinib fails to eradicate leukemia stem cells (LSCs), the underlying mechanisms maintaining CML LSCs remain poorly understood. Here, we showed that transient inhibition of miR-21 by antagomiR-21 markedly increased imatinib-induced apoptosis in CML, but not normal CD34+ stem/progenitor cells. Furthermore, PI3K inhibitors also significantly sensitized CML CD34+ cells to imatinib-induced apoptosis. MiR-21 or PI3K inhibitor in combination with imatinib treatment significantly decreased AKT phosphorylation and c-Myc expression than either agent did alone, but did not affect Bim and Bcl-6 expresssion. These findings indicate that miR-21 is required for maintaining the imatinib-resistant phenotype of CML CD34+ cells through PI3K/AKT signaling pathway, thus providing the basis for a promising therapeutic approach to eliminate CML LSCs.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , MicroARNs/antagonistas & inhibidores , Células Madre Neoplásicas/efectos de los fármacos , Transducción de Señal , Adulto , Antígenos CD34/inmunología , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Niño , Femenino , Silenciador del Gen , Humanos , Mesilato de Imatinib/farmacología , Lactante , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Masculino , Persona de Mediana Edad , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal/fisiología , Transfección , Adulto Joven
16.
Biochem Biophys Res Commun ; 454(3): 423-8, 2014 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-25451263

RESUMEN

Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL) cells are insensitive to BCR-ABL tyrosine kinase inhibitor imatinib, the underlying mechanisms remain largely unknown. Here, we showed that imatinib treatment induced significant upregulation of miR-21 and downregulation of PTEN in Ph+ ALL cell line Sup-b15. Transient inhibition of miR-21 resulted in increased apoptosis, PTEN upregulation and AKT dephosphorylation, whereas ectopic overexpression of miR-21 further conferred imatinib resistance. Furthermore, knockdown of PTEN protected the cells from imatinib-induced apoptosis achieved by inhibition of miR-21. Additionally, PI3K inhibitors also notably enhanced the effects of imatinib on Sup-b15 cells and primary Ph+ ALL cells similar to miR-21 inhibitor. Therefore, miR-21 contributes to imatinib resistance in Ph+ ALL cells and antagonizing miR-21 demonstrates therapeutic potential by sensitizing the malignancy to imatinib therapy.


Asunto(s)
Antineoplásicos/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Mesilato de Imatinib/farmacología , MicroARNs/genética , Oligonucleótidos/farmacología , Fosfohidrolasa PTEN/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Antagomirs , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Inhibidores de las Quinasa Fosfoinosítidos-3 , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Inhibidores de Proteínas Quinasas/farmacología , Interferencia de ARN , ARN Interferente Pequeño/genética , Regulación hacia Arriba/efectos de los fármacos
17.
World J Microbiol Biotechnol ; 30(10): 2577-85, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24906465

RESUMEN

To develop a novel yeast whole-cell biocatalyst by yeast surface display technology that can hydrolyze chitin, the chitinaseC gene from Serratia marcescens AS1.1652 strain was cloned and subcloned into the yeast surface display plasmid pYD1, and the recombinant plasmid pYD1/SmchiC was electroporated into Saccharomyces cerevisiae EBY100 cell. Aga2p-SmChiC fusion protein was expressed and anchored on the yeast cell surface by induction with galactose, which was verified by indirect immunofluorescence and Western blotting. The chitinolytic activity of the yeast whole-cell biocatalyst or partially purified enzyme was detected by agar plate clear zone test, SDS-PAGE zymography and dinitrosalicylic acid method. The results showed that the chitinaseC gene from S. marcescens AS1.1652 strain was successfully cloned and expressed on the yeast cell surface, Aga2p-SmChiC fusion protein with molecular weight (67 kDa) was determined. Tests on the effect of temperature and pH on enzyme activity and stability revealed that the yeast whole-cell biocatalyst and partially purified enzyme possessed both thermal stability and activity, and even maintained some activity under acidic and weakly alkaline conditions. The optimum reaction temperature and pH value were set at 52 °C and 5.0, respectively. Yeast surface display technology succeeded in preparing a yeast whole-cell biocatalyst with chitinolytic activity, and the utilization of chitin could benefit from this process of enzyme preparation.


Asunto(s)
Proteínas Bacterianas/metabolismo , Quitinasas/metabolismo , Clonación Molecular/métodos , Saccharomyces cerevisiae/genética , Serratia marcescens/enzimología , Proteínas Bacterianas/genética , Biocatálisis , Pared Celular/metabolismo , Quitinasas/genética , Electroporación , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Proteínas de Plantas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/metabolismo , Temperatura
18.
Am J Chin Med ; 41(5): 1153-68, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24117075

RESUMEN

Although Wedelia chinensis, an herb in traditional Chinese medicine, has been widely used for the treatment of inflammation, the effects of W. chinensis on cancer cell growth and the related molecular mechanisms behind these effects have largely remained unexplored to date. In the present study, W. chinensis plant extracts were obtained using either ethanol (E), petroleum ether (PE), ethyl acetate (EA) or butyl alcohol (BA). Then, extracts were examined for bioactivity in vitro via MTT assay in five human cancer cell lines. Our results showed that one subfraction of the EA extract (EA6) was cytotoxic to nasopharyngeal carcinoma (NPC) CNE-1 cells, among all cell lines evaluated. Treatment of CNE-1 cells with EA6 resulted in significant G2/M cell cycle arrest and modest apoptosis. EA6 induced Chk1 activation and inhibition of Chk1 in CNE-1 cells by RNA interference (RNAi) markedly abrogated EA6-mediated G2/M arrest and abolished EA6-induced cytotoxicity. EA6 treatment resulted in notable reduction of c-myc expression in CNE-1 cells, whereas silencing Chk1 inhibited such effects of EA6. Our results indicate that Chk1 is a novel molecular target of EA6 in NPC cells and also suggest an intervention strategy for NPC by EA6 exploring its molecular mechanisms of action.


Asunto(s)
Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , Extractos Vegetales/farmacología , Proteínas Quinasas/genética , Proteínas Quinasas/fisiología , Transducción de Señal/genética , Transducción de Señal/fisiología , Wedelia , Apoptosis/genética , Carcinoma , Línea Celular Tumoral , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Expresión Génica/efectos de los fármacos , Silenciador del Gen , Genes myc/genética , Humanos , Terapia Molecular Dirigida , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Interferencia de ARN
19.
Food Chem Toxicol ; 59: 464-9, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23816833

RESUMEN

Musca domestica larvae extracts (MDLE) is a potential drug used to treat lipopolysaccharide-induced atherosclerosis pro-inflammatory responses. The purpose of the study was to evaluate the safety of MDLE via a 13-week repeated dose subchronic toxicity test in rats. Both male and female Sprague Dawley rats were divided into four groups, eight animals each from the control and high-dose group (33.0 g/kg) were allocated into recovery groups. The four groups of rats were administrated with MDLE (0, 13.2, 22.0, 33.0 g/kg) in the diet for 13weeks respectively. During the experimental period, the rats were observed for symptoms and signs of gross toxicity daily, food consumption and body weight were measured weekly. Urinalysis, thrombotest, blood biochemical and hematological analyses were performed regularly; Expression of peroxide dismutase gene in liver was quantified and a histopathological examination was also performed. There were no MDLE-induced abnormalities in any of the groups during or after the 13 weeks except the relative weight of liver of high-dose group and middle-dose group was significantly higher than that of control group in male rats (P<0.05). The results indicate a no observed adverse effect level for MDLE is 13.2 and 33.0 g/kg bw/day in male and female rats, respectively.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Productos Biológicos/efectos adversos , Moscas Domésticas/química , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/inmunología , Productos Biológicos/administración & dosificación , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Etnofarmacología , Femenino , Hepatomegalia/inducido químicamente , Hepatomegalia/metabolismo , Hepatomegalia/patología , Larva/química , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Medicina Tradicional China , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos/efectos de los fármacos , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Pruebas de Toxicidad Subcrónica
20.
Life Sci ; 92(6-7): 352-8, 2013 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-23352975

RESUMEN

AIM: The aim of this study is to explore the underlying molecular mechanism of curcumin-induced apoptosis in human hepatocellular carcinoma (HCC) Huh7 cells. MAIN METHODS: Fas and FasL mRNA expression was analyzed by reverse transcription PCR. Western blot was applied to detect the protein expression of Bcl-2 family members, MAPK family members, c-Jun, c-Fos, ATF-2, caspase-3, PARP, TNF receptor family members and the respective ligands. Apoptotic cells were assayed with annexin V/PI double staining and flow cytometry. KEY FINDINGS: Curcumin treatment resulted in a fast and significant increase of Fas and Fas ligand (FasL) along with activation of caspase-3 and cleavage of PARP in Huh7 cells. Inhibition of caspase-3 activity by the specific inhibitor Z-DEVD-FMK rescued Huh7 cells from curcumin-induced apoptosis. Neutralization of FasL significantly protected the cells from curcumin-induced caspase-3 activation and apoptosis in a dose-dependent manner. Moreover, p38 was rapidly activated in response to curcumin, and inactivation of p38 by pharmacologic inhibitor SB203580 dramatically suppressed curcumin-induced FasL expression and apoptosis. SIGNIFICANCE: Our results demonstrated that curcumin induces apoptosis through p38-denpendent up-regulation of FasL in Huh7 cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Curcumina/farmacología , Proteína Ligando Fas/biosíntesis , Receptor fas/biosíntesis , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Carcinoma Hepatocelular/patología , Caspasa 3/biosíntesis , Inhibidores de Caspasas/farmacología , Línea Celular Tumoral , Humanos , Imidazoles/farmacología , Oligopéptidos/farmacología , Fosforilación/efectos de los fármacos , Piridinas/farmacología , Transducción de Señal/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores
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