Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 99
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Ind Microbiol Biotechnol ; 50(1)2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-37580133

RESUMEN

Astaxanthin has high utilization value in functional food because of its strong antioxidant capacity. However, the astaxanthin content of Phaffia rhodozyma is relatively low. Adaptive laboratory evolution is an excellent method to obtain high-yield strains. TiO2 is a good inducer of oxidative stress. In this study, different concentrations of TiO2 were used to domesticate P. rhodozyma, and at a concentration of 1000 mg/L of TiO2 for 105 days, the optimal strain JMU-ALE105 for astaxanthin production was obtained. After fermentation, the astaxanthin content reached 6.50 mg/g, which was 41.61% higher than that of the original strain. The ALE105 strain was fermented by batch and fed-batch, and the astaxanthin content reached 6.81 mg/g. Transcriptomics analysis showed that the astaxanthin synthesis pathway, and fatty acid, pyruvate, and nitrogen metabolism pathway of the ALE105 strain were significantly upregulated. Based on the nitrogen metabolism pathway, the nitrogen source was adjusted by ammonium sulphate fed-batch fermentation, which increased the astaxanthin content, reaching 8.36 mg/g. This study provides a technical basis and theoretical research for promoting industrialization of astaxanthin production of P. rhodozyma. ONE-SENTENCE SUMMARY: A high-yield astaxanthin strain (ALE105) was obtained through TiO2 domestication, and its metabolic mechanism was analysed by transcriptomics, which combined with nitrogen source regulation to further improve astaxanthin yield.


Asunto(s)
Xantófilas , Evolución Molecular Dirigida , Perfilación de la Expresión Génica , Basidiomycota/química , Basidiomycota/clasificación , Basidiomycota/genética , Basidiomycota/crecimiento & desarrollo , Biomasa , Glucosa/análisis , Carotenoides/análisis , Fermentación , Técnicas de Cultivo Celular por Lotes , Nitrógeno/metabolismo , Xantófilas/química , Xantófilas/metabolismo
2.
J Med Internet Res ; 25: e40735, 2023 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-37982411

RESUMEN

BACKGROUND: Knee osteoarthritis (OA) is a chronic, degenerative bone and joint disease. It can lead to major pressure to the quality of life and mental health of patients, and also brings a serious economic burden to society. However, it is difficult for patients with knee OA to access rehabilitation when discharging from the hospital. Internet-based rehabilitation is one of the promising telemedicine strategies for the improvement of knee OA, but the effect of different telerehabilitation strategies on knee OA is not clear. OBJECTIVE: The aim of this systematic review and meta-analysis was to identify telerehabilitation strategies attributing to the improvement of pain and physical function outcomes in patients with knee OA. METHODS: We reviewed and analyzed telerehabilitation strategies from randomized controlled trials (RCTs) comparing telerehabilitation with conventional treatment or usual care. For each strategy, we examined whether RCTs that applied the telerehabilitation strategy resulted in a significant improvement in pain or physical function compared with conventional treatment or usual care. RESULTS: We included 6 RCTs (n=734) incorporating 8 different telerehabilitation strategies. The duration of the interventions ranged from 1 to 48 weeks, and sample sizes ranged from 20 to 350 patients. The results showed that RCTs that provided telerehabilitation were found to be more effective than conventional treatments for improving pain (P=.003; standardized mean difference [SMD] -0.21, 95% CI -0.35 to -0.07), but not physical function (P=.24; SMD -0.09, 95% CI -0.25 to 0.06). Furthermore, this systematic review and meta-analysis indicated that there is no significant correlation between different telerehabilitation strategies and the pain and physical function of patients with knee OA. CONCLUSIONS: This systematic review and meta-analysis showed that telerehabilitation programs could relieve pain but not improve physical function for patients with knee OA. These results indicated that telerehabilitation is beneficial for the implementation of home rehabilitation exercises for patients with knee OA, thereby reducing the economic burden of health. However, there were limitations in terms of the number of search results and the number of studies that were eligible for this review and meta-analysis. Therefore, the results need to be interpreted with caution, and more high-quality studies with large samples are needed to focus on the long-term outcomes of telerehabilitation for patients with knee OA to address this limitation.


Asunto(s)
Osteoartritis de la Rodilla , Telemedicina , Telerrehabilitación , Humanos , Osteoartritis de la Rodilla/rehabilitación , Telerrehabilitación/métodos , Dolor , Terapia por Ejercicio/métodos
3.
Glob Chang Biol ; 28(1): 154-166, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34651373

RESUMEN

No-till (NT) is a sustainable option because of its benefits in controlling erosion, saving labor, and mitigating climate change. However, a comprehensive assessment of soil pH response to NT is still lacking. Thus, a global meta-analysis was conducted to determine the effects of NT on soil pH and to identify the influential factors and possible consequences based on the analysis of 114 publications. When comparing tillage practices, the results indicated an overall significant decrease by 1.33 ± 0.28% in soil pH under NT than that under conventional tillage (p < .05). Soil texture, NT duration, mean annual temperature (MAT), and initial soil pH are the critical factors affecting soil pH under NT. Specifically, with significant variations among subgroups, when compared to conventional tillage, the soil under NT had lower relative changes in soil pH observed on clay loam soil (-2.44%), long-term implementation (-2.11% for more than 15 years), medium MAT (-1.87% in the range of 8-16℃), neutral soil pH (-2.28% for 6.5 < initial soil pH < 7.5), mean annual precipitation (-1.95% in the range of 600-1200 mm), in topsoil layers (-2.03% for 0-20 cm), with crop rotation (-1.98%), N fertilizer input (the same for NT and conventional tillage) of 100-200 kg N ha-1 (-1.83%), or crop residue retention (-1.52%). Changes in organic matter decomposition under undisturbed soil and with crop residue retention might lead to a higher concentration of H+ and lower of basic cations (i.e., calcium, magnesium, and potassium), which decrease the soil pH, and consequently, impact nutrient dynamics (i.e., soil phosphorus) in the surface layer under NT. Furthermore, soil acidification may be aggravated by NT within site-specific conditions and improper fertilizer and crop residue management and consequently leading to adverse effects on soil nutrient availability. Thus, there is a need to identify strategies to ameliorate soil acidification under NT to minimize the adverse consequences.


Asunto(s)
Agricultura , Suelo , Cambio Climático , Fertilizantes , Concentración de Iones de Hidrógeno
4.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(2): 192-197, 2021 Feb.
Artículo en Zh | MEDLINE | ID: mdl-33627217

RESUMEN

At present, effective antibiotics and comprehensive symptomatic/supportive treatment as early as possible are mainly used for the treatment of severe pertussis in clinical practice. However, some children with severe pertussis have unsatisfactory response to commonly used drugs and treatment measures in the intensive care unit and thus have a high risk of death. Studies have shown that certain treatment measures given in the early stage, such as exchange transfusion, may help reduce deaths, but there is still a lack of uniform implementation norms. How to determine the treatment regimen for severe pertussis and improve treatment ability remains a difficult issue in clinical practice. This article reviews the advances in the treatment of severe pertussis, in order to provide a reference for clinical treatment and research.


Asunto(s)
Tos Ferina , Antibacterianos , Niño , Recambio Total de Sangre , Humanos , Tos Ferina/tratamiento farmacológico
5.
J Org Chem ; 85(16): 10924-10933, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32786223

RESUMEN

A highly efficient electrophilic oxyselenation of propargylic amines with diselenides and CO2 under atmospheric pressure promoted by copper/DTBP is reported. Various biologically important selenyl 2-oxazolidinones were produced in moderate to excellent yields. The developed method features a broad substrate scope, easy scalability, and mild reaction conditions.

6.
Nanotechnology ; 31(23): 235703, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-32059208

RESUMEN

A hydroxyapatite whisker (w-HA) was synthesized via dissolution-precipitation by forming calcium-ethylene diamine tetra acetic acid (Ca-EDTA) complexing. The hydroxyapatite whisker was formed with precipitation of Ca2+ along the c-axis due to the space inhibition of Ca-EDTA complex during refluxing. The op-w-HA (oligomeric poly(lactic acid) modified w-HA), p-w-HA (poly(L-lactide) modified w-HA) and pc-w-HA (poly(L-lactide) and cyclodextrin modified w-HA) were obtained via the surface modification of w-HA. The particle size, surface charge and biocompatibility of theses modified w-HA particles were successfully adjusted. Among these materials, pc-w-HA exhibited nearly no toxicity, better adhesion to mesenchymal stem cells (MSCs) (5 times better than w-HA) and greater osteoinductivity among the obtained materials (40% of mineralized extracellular matrix higher than w-HA) due to better surface properties. Different kinds of powders (w-HA, p-w-HA and pc-w-HA) were blended with PLLA (poly(L-Lactide)) to form a composite material, respectively. The pc-w-HA/PLLA composite showed better mechanical properties (tensile strength of the pc-w-HA/PLLA composite was 22.3% higher than that of w-HA/PLLA), which could be attributed to mainly two factors including the structure preservation of w-HA bundles and pseudorotaxane linkage between PLA-cyclodextrin and PLLA. The MSCs adhesion of the pc-w-HA/PLLA composite was much better due to balanced hydrophilicity/hydrophobicity and surface roughness. This surface modification method could provide a new and effective strategy for the preparation of bioresorbable composite material with great bioactivity and mechanical property, which has great potential in the medical device industry.

7.
Int J Med Sci ; 17(1): 97-102, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31929743

RESUMEN

Colorectal cancer (CRC) is one of the most common cancers in Han Chinese and is characterized by low rates of early diagnosis and poor survival rates. Angiopoietin-2 (Ang2), an endothelial tyrosine kinase, is involved in CRC progression, but little is known about the association between single nucleotide polymorphisms (SNPs) and diagnosis or prognosis of CRC. This study reports on the association between 5 SNPs of the Angpt2 gene (rs2442598, rs734701, rs1823375, 11137037, and rs12674822) and CRC susceptibility as well as clinical outcomes in 379 patients with CRC and in 1,043 cancer-free healthy controls. Carriers of the CG allele at rs1823375 and those with the GT+TT allele of the variant rs12674822 were at greater risk of CRC than their respective wild-type counterparts. Moreover, carriers of the GT or GT+TT allele in rs12674822 were significantly more likely to have tumor involvement in both the colon and rectum compared with wild-type (GG) carriers, while 5-year progression-free survival was also significantly worse in those carrying the GT+TT allele in rs12674822 compared with wild-type carriers. Our study is the first to describe correlations between Angpt2 polymorphisms and CRC development and progression in people of Chinese Han ethnicity.


Asunto(s)
Angiopoyetina 2/genética , Biomarcadores de Tumor/genética , Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad , Adulto , Alelos , Neoplasias Colorrectales/patología , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Estudios de Asociación Genética , Genotipo , Heterocigoto , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Pronóstico
8.
Molecules ; 25(16)2020 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-32784994

RESUMEN

The aroma of an instant white tea (IWT) was extracted through simultaneous distillation-extraction (SDE) and analyzed by sensory evaluation, gas chromatography-mass spectrometry-olfactometry (GC-MS-O), aroma reconstruction, omission test and synergistic interaction analysis. Sensory evaluation showed the IWT was dominated with floral and sweet notes. The SDE extract had the aroma similar to the IWT. The main volatile components in the SDE extract were benzyl alcohol, linalool, hotrienol, geraniol, α-terpineol, coumarin, camphene, benzeneacetaldehyde, 2-hexanone, cis-jasmin lactone and phenylethyl alcohol. GC-MS-O and aroma reconstruction experiments showed 16 aroma-active compounds. Linalool, trans-ß-damascenone and camphene were the major contributors to floral, sweet and green notes based on flavor dilution analysis and omission test. Linalool and trans-ß-damascenone had synergistic effect to promote floral and sweet notes. Camphene and trans-ß-damascenone had synergistic effect to reduce green and sweet notes. The study helps to understand the aroma of IWT and antagonism interactions among aroma-active volatiles.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Odorantes/análisis , Té/química , Compuestos Orgánicos Volátiles/química , Adulto , Destilación , Femenino , Liofilización , Humanos , Masculino , Olfatometría , Microextracción en Fase Sólida , Umbral Gustativo , Té/metabolismo , Compuestos Orgánicos Volátiles/aislamiento & purificación , Adulto Joven
9.
Prep Biochem Biotechnol ; 50(1): 1-9, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31441715

RESUMEN

Isoquercitrin is a flavonoid with important applications in the pharmaceutical and nutraceutical industries. However, a low yield and high production cost hinders the industrial preparation of isoquercitrin. In the present study, isoquercitrin was prepared by biotransformation of rutin using α-L-rhamnosidase from Aspergillus niger JMU-TS528 combined with high-speed countercurrent chromatography (HSCCC) purification. As a result, the optimum transformation pH, temperature, and time were pH 4.0, 60 °C, and 60 min, respectively. The Km and Vmax were 0.36 mM and 0.460 mmol/min, respectively. For isoquercitrin production, the optimal rutin concentration and transformation time were approximately 1000 mg/L and 60 min. The rutin transformation rate reached 96.44%. The isoquercitrin was purified to a purity of 97.83% using one-step purification with HSCCC. The isoquercitrin was identified using UPLC-Q-TOF-MS. The comprehensive results indicated that the biotransformation procedure using the α-L-rhamnosidase from A. niger JMU-TS528 combined with HSCCC was a simple and effective process to prepare isoquercitrin, which might facilitate the production of isoquercitrin for industrial use.


Asunto(s)
Aspergillus niger/metabolismo , Glicósido Hidrolasas/metabolismo , Quercetina/análogos & derivados , Rutina/metabolismo , Biotransformación , Distribución en Contracorriente , Microbiología Industrial , Quercetina/aislamiento & purificación , Quercetina/metabolismo
10.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(4): 468-476, 2020 Aug 30.
Artículo en Zh | MEDLINE | ID: mdl-32895098

RESUMEN

Objective To establish an improved animal model of sepsis induced by cecal ligation and puncture(CLP). Methods Ninety-six male Sprague-Dawley rats were randomly divided into sham operation group(n=24),intubation group(n=24),CLP group(n=24),and CLP+intubation group(n=24).The mortality rate,abdominal cavity condition,pathological changes and pathological scores of heart,lungs,liver,and kidneys of rats in each group were observed after modeling.Blood samples were obtained from the inferior vena cava for measuring the whole blood cells(WBC)and platelets(PLT)counts and analyzing serum interleukin(IL)-6,tumor necrosis factor(TNF)-α,serum troponin T(cTnT),creatine kinase-MB(CK-MB),alanine aminotransferase(ALT),aspartate aminotransferase(AST),total bilirubin(TBIL),creatinine(CREA),and blood urea nitrogen(BUN)levels.Blood gas analysis of the aorta was also performed. Results The mortality rates 24 h after modeling were 0 in sham operation group and intubation group,20.8% in CLP group,and 54.2% in CLP+intubation group.Pathologically,swelling and inflammatory cell infiltration in the heart,lungs,liver,and kidneys were seen in the CLP+intubation group,inflammatory cell infiltration in a single organ was seen in most rats in the CLP group,and no obvious swelling and infiltration of inflammatory cells was observed in the sham-operation group and intubation group.The myocardial histopathology score,lung tissue injury pathology score,and kidney tissue injury pathology score in both the sham-operation group and the intubation group were significantly lower than those in the CLP group and the CLP+intubation group(all P=0.000).TNF-α,PaO2,CK-MB,cTnT,AST,TBIL,BUN,and CREA were significantly different between sham-operation group and intubation group/CLP group/CLP+intubation group and between intubation group and CLP group/CLP+intubation group(all P=0.000).The pH level was significantly different between sham operation group and intubation group/CLP group,between intubation group and CLP group/CLP+intubate group(all P=0.000). Conclusions Although both CLP and CLP+intubation can well mimic the pathophysiological mechanism of sepsis in rats,multiple organ dysfunction occurs in the latter.Thus,CLP+intubation can establish animal models of multiple organ dysfunction caused by sepsis induced by clinically effective abdominal infection.


Asunto(s)
Sepsis , Animales , Aspartato Aminotransferasas , Modelos Animales de Enfermedad , Ligadura , Masculino , Punciones , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa
11.
Int J Mol Sci ; 20(24)2019 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-31817978

RESUMEN

Citrus fruits are mainly consumed as fresh fruit and processed juice products. They serve as nutritional and a tasty diet in our daily life. However, the formidable bitterness and delayed bitterness significantly impact the citrus industry attributable to the two major bitter compounds naringin and limonin. The extremely sour and acidic also negatively affects the sensory quality of citrus products. Citrus breeding programs have developed different strategies to improve citrus quality and a wealth of studies have aimed to uncover the genetic and biochemical basis of citrus flavor. In this minireview, we outline the major genes characterized to be involved in pathways shaping the sweet, bitter, or sour taste in citrus, and discuss briefly about the possible approaches to modify citrus taste by genetic engineering.


Asunto(s)
Citrus/química , Frutas/química , Gusto , Citrus/metabolismo , Flavanonas , Frutas/metabolismo , Ingeniería Genética , Limoninas
12.
Molecules ; 24(24)2019 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-31817626

RESUMEN

The unpleasant stale note is a negative factor hindering the consumption of instant ripened Pu-erh tea products. This study focused on investigating volatile chemicals in instant ripened Pu-erh tea that could mask the stale note via sensory evaluation, gas chromatography-mass spectrometry (GC-MS), and gas chromatography-olfactometry (GC-O) analyses. GC-MS and GC-O analyses showed that linalool, linalool oxides, trans-ß-ionone, benzeneacetaldehyde, and methoxybenzenes were the major aroma contributors to the simultaneous distillation and extraction (SDE) extract of instant ripened Pu-erh tea. Sensory evaluation showed that the SDE extract had a strong stale note, which was due to methoxybenzenes. By investigating suppressive interaction among flavour components, the stale note from methoxybenzenes was shown to have reciprocal masking interactions with sweet, floral, and green notes. Moreover, the validation experiment showed that the addition of 40 µg/mL of trans-ß-ionone in the instant ripened Pu-erh tea completely masked the stale note and improved the overall aromatic acceptance. These results elucidate the volatile chemicals that could mask the stale note of instant ripened Pu-erh tea products, which might help to develop high quality products made from instant ripened Pu-erh tea.


Asunto(s)
Extractos Vegetales/química , Té/química , Monoterpenos Acíclicos/química , Anisoles/química , Ciclohexanoles/química , Cromatografía de Gases y Espectrometría de Masas , Compuestos de Tritilo/química
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(3): 208-213, 2019 Mar.
Artículo en Zh | MEDLINE | ID: mdl-30907341

RESUMEN

OBJECTIVE: To investigate the alternative antimicrobial drugs for the treatment of neonatal pertussis and the antigen genotypes of Bordetella pertussis (B. pertussis) strains. METHODS: A total of 32 B. pertussis strains isolated from neonates between May 2013 and July 2018 were used in this study. E-test stripes were used to measure the minimal inhibitory concentration (MIC) of 18 antimicrobial drugs including erythromycin, sulfamethoxazole-trimethoprim (SMZ) and ampicillin. The 23S rRNA gene of isolated strains was amplified and sequenced to identify the mutation site of erythromycin resistance gene, and the seven antigen genotypes of B. pertussis strains (ptxA, ptxC, ptxP, prn, fim2, fim3 and tcfA2) were analyzed. RESULTS: Of the 32 B. pertussis strains, 25 (78%) were resistant to erythromycin, azithromycin, clarithromycin and clindamycin, with an MIC of >256 mg/L, and A2047G mutation was observed in the 23S rRNA gene. All strains had an MIC of ≤0.064 mg/L for SMZ. The MIC of ampicillin, amoxicillin, amoxicillin-clavulanic acid and ceftriaxone ranged from 0.032 to 1 mg/L. The strains resistant to macrolide antibiotics had an antigen genotype of ptxA1/ptxC1/ptxP1/prn1/fim2-1/fim3-1/tcfA2. CONCLUSIONS: B. pertussis strains from neonates are often resistant to macrolides, and the in vitro test shows that off-label use of sulfonamides is a reliable regimen for the treatment of neonates with macrolide-resistant pertussis. The prevalence of drug-resistant strains further emphasizes the importance of immunoprophylaxis.


Asunto(s)
Bordetella pertussis/genética , Antibacterianos , Eritromicina , Genotipo , Humanos , Recién Nacido , Pruebas de Sensibilidad Microbiana , Tos Ferina
14.
J Cell Mol Med ; 22(4): 2098-2109, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29372627

RESUMEN

Recent findings demonstrate that leptin plays a significant role in chondrocyte and osteoblast differentiation. However, the mechanisms by which leptin acts on cartilage endplate (CEP) cells to give rise to calcification are still unclear. The aim of this study was to evaluate the effects of leptin that induced mineralization of CEP cells in vitro and in vivo. We constructed a rat model of lumbar disc degeneration and determined that leptin was highly expressed in the presence of CEP calcification. Rat CEP cells treated with or without leptin were used for in vitro analysis using RT-PCR and Western blotting to examine the expression of osteocalcin (OCN) and runt-related transcription factor 2 (Runx2). Both OCN and Runx2 expression levels were significantly increased in a dose- and time-dependent manner. Leptin activated ERK1/2 and STAT3 phosphorylation in a time-dependent manner. Inhibition of phosphorylated ERK1/2 using targeted siRNA suppressed leptin-induced OCN and Runx2 expression and blocked the formation of mineralized nodules in CEP cells. We further demonstrated that exogenous leptin induced matrix mineralization of CEP cells in vivo. We suggest that leptin promotes the osteoblastic differentiation of CEP cells via the MAPK/ERK signal transduction pathway and may be used to investigate the mechanisms of disc degeneration.


Asunto(s)
Cartílago/enzimología , Cartílago/patología , Degeneración del Disco Intervertebral/enzimología , Degeneración del Disco Intervertebral/patología , Leptina/farmacología , Sistema de Señalización de MAP Quinasas , Osteogénesis/efectos de los fármacos , Animales , Calcificación Fisiológica/efectos de los fármacos , Cartílago/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Modelos Animales de Enfermedad , Vértebras Lumbares/efectos de los fármacos , Vértebras Lumbares/patología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Placa Motora/efectos de los fármacos , Placa Motora/patología , Osteocalcina/metabolismo , Fosforilación/efectos de los fármacos , Ratas Sprague-Dawley , Factor de Transcripción STAT3/metabolismo
15.
Bioorg Med Chem Lett ; 28(3): 394-399, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29275936

RESUMEN

Akt, also known as protein kinase B (PKB), is a serine/threonine kinase that promotes survival and growth in response to extracellular signals. Akt1 has been demonstrated to play vital roles in cardiovascular diseases, but the role of Akt2 in cardiomyocytes is not fully understood. This study investigated the effect of Akt2 knockdown on tunicamycin (TM)-induced cytotoxicity in cardiomyocytes and the underlying mechanisms with a focus on the JNK-Wnt pathway. TM treatment significantly increased the expression of Akt2 at both mRNA and protein levels, which was shown to be mediated by the induction of reactive oxygen species (ROS). Knockdown of Akt2 expression via siRNA transfection markedly increased cell viability, decreased lactate dehydrogenase (LDH) release and reduced cell apoptosis after TM exposure. The results of western blot showed that downregulation of Akt2 also attenuated the TM-induced activation of the unfolded protein response (UPR) factors and ER stress associated pro-apoptotic proteins. In addition, Si-Akt2 transfection partially prevented the TM-induced decrease in nuclear localization of ß-catenin. By using the selective inhibitor SP-600,125 to inhibit JNK phosphorylation, we found that knockdown of Akt2-induced protection and inhibition of ER stress was mediated by reversing TM-induced decrease of Wnt through the JNK pathway. In summary, these data suggested that Akt2 play a pivotal role in regulating cardiomyocyte survival during ER stress by modulating the JNK-Wnt pathway.


Asunto(s)
Regulación hacia Abajo/efectos de los fármacos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Tunicamicina/farmacología , Apoptosis/efectos de los fármacos , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Estrés del Retículo Endoplásmico/efectos de los fármacos , Humanos , Modelos Moleculares , Estructura Molecular , Miocitos Cardíacos/metabolismo , Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas c-akt/metabolismo , Relación Estructura-Actividad , Tunicamicina/química , Vía de Señalización Wnt/efectos de los fármacos
16.
Biosci Biotechnol Biochem ; 81(6): 1081-1089, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28290776

RESUMEN

A series of reduced amino pyridine Schiff base platinum(II) complexes were prepared as potential anticancer drugs, and characterized by NMR, IR spectroscopy, elemental analysis, and molar conductivity. UV and CD results showed the binding mode between these compounds and salmon sperm DNA may be intercalation. The cytotoxicity of these complexes was validated against A549, Hela, and MCF-7 cell lines by MTT assay. Some complexes exhibited better cytotoxic activity than cisplatin against Hela and MCF-7 cell lines.


Asunto(s)
Antineoplásicos/síntesis química , Sustancias Intercalantes/síntesis química , Compuestos Organoplatinos/síntesis química , Piridinas/química , Bases de Schiff/química , Células A549 , Animales , Antineoplásicos/farmacología , Sitios de Unión , Supervivencia Celular/efectos de los fármacos , ADN/química , Relación Dosis-Respuesta a Droga , Células HeLa , Humanos , Concentración 50 Inhibidora , Sustancias Intercalantes/farmacología , Ligandos , Células MCF-7 , Masculino , Compuestos Organoplatinos/farmacología , Salmón , Espermatozoides/química , Relación Estructura-Actividad
17.
Tetrahedron Lett ; 57(46): 5047-5049, 2016 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-28066032

RESUMEN

One dimeric matrine-type alkaloid, ochrocephalamine A (1), was isolated from the poisonous plant Oxytropis ochrocephala Bunge. Its structure was elucidated by spectroscopic data and single-crystal X-ray diffraction. The insecticidal and cytotoxic activities of 1 were evaluated.

18.
Nano Lett ; 15(3): 1861-6, 2015 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-25626012

RESUMEN

In this work, we demonstrate abrupt, reversible switching of resistance in 1T-TaS2 using dc and pulsed sources, corresponding to an insulator-metal transition between the insulating Mott and equilibrium metallic states. This transition occurs at a constant critical resistivity of 7 mohm-cm regardless of temperature or bias conditions and the transition time is significantly smaller than abrupt transitions by avalanche breakdown in other small gap Mott insulating materials. Furthermore, this critical resistivity corresponds to a carrier density of 4.5 × 10(19) cm(-3), which compares well with the critical carrier density for the commensurate to nearly commensurate charge density wave transition. These results suggest that the transition is facilitated by a carrier driven collapse of the Mott gap in 1T-TaS2, which results in fast (3 ns) switching.

19.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(5): 665-668, 2016 Sep.
Artículo en Zh | MEDLINE | ID: mdl-28598076

RESUMEN

OBJECTIVES: To examine the effects of RUNX3 on cell proliferation and apoptosis and the expression level of Smad4 mRNA in the bladder cancer cell line of T24 by transfection with recombinant plasmid of pIRES-EGFP-RUNX3. METHODS: The recombinant plasmid of pIRES-EGFP-RUNX3 was constructed successfully. Cultured T24 cells were divided into three groups, including control group, empty vector group,and recombinant plasmid group. The cells in empty vector group and recombinant plasmid group were respectively transfected by pIRES-EGFP and pIRES-EGFP-RUNX3 The cells were harvested at 24 h after the transfection, the variation of cell morphology was examined by fluorescence microscopy. The cell apoptosis was detected by flow cytometry. The expression level of RUNX3 and Smad4 mRNA was measured by RT-PCR. RESULTS: Cell death was observed in two transfection groups. At 24 h after transfection,the apoptosis rate was (3.23±0.45)% in control group, (8.98±1.62)% in empty vector group and (43.61±2.69)% in recombinant plasmid group. The expression level of RUNX3 mRNA was 2.79±0.36,detected only in recombinant plasmid group, which was significantly up-regulated compared with the other two groups (P<0.05). CONCLUSIONS: The expression level of Smad4 mRNA was up-regulated by transfection with pIRES-EGFP-RUNX3,which also inhibited cell proliferation and promoted cell apoptosis.The tumor suppressor gene of RUNX3 could regulate the bladder cancer cell proliferation and apoptosis by TGF-ß/Smad signaling pathway.


Asunto(s)
Apoptosis , Subunidad alfa 3 del Factor de Unión al Sitio Principal/genética , Proteína Smad4/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo , Línea Celular Tumoral , Proliferación Celular , Humanos , Plásmidos , Transducción de Señal , Transfección
20.
J Ultrasound Med ; 34(6): 1107-14, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26014331

RESUMEN

OBJECTIVES: The purpose of this study was to sonographically assess the cerebral hemodynamic differences and changes after oxygen therapy in healthy youths of different ethnicities in Tibet. METHODS: Sixty-six healthy young Han visitors and 29 healthy young Tibetan residents were divided into 4 groups. Basic information was collected. Pulsed Doppler sonography was used to record the cerebral hemodynamic parameters for the internal carotid, vertebral, and middle cerebral arteries. The participants were then instructed to inhale oxygen, and basic information and cerebral hemodynamic parameters were recorded at 1, 2, 4, and 8 minutes, respectively. Differences in these parameters between groups were analyzed. RESULTS: In comparisons of the flow parameters between sex-matched groups, the mean resistive index values for the internal carotid, vertebral, and middle cerebral arteries in the Han groups were significantly lower than those in the Tibetan groups (P <. 05). The mean peak systolic velocity, end-diastolic velocity, and mean velocity values for the middle cerebral artery in the Han groups were significantly higher than those in the Tibetan groups (P < .05). After oxygen uptake, there were no significant differences in the mean arterial oxygen saturation, heart rate, mean velocity, and resistive index values between the male groups, and similar changes were found for the arterial oxygen saturation and peak systolic velocity values between female groups after 8 minutes of oxygen uptake (P > .05). CONCLUSIONS: Sonography is a useful modality for noninvasive and real-time detection of changes in cerebral hemodynamics and can provide reference values for the prevention and treatment of cerebrovascular diseases.


Asunto(s)
Circulación Cerebrovascular , Hemodinámica , Terapia por Inhalación de Oxígeno , Ultrasonografía Doppler de Pulso , Ultrasonografía Doppler Transcraneal , Adolescente , Edema Encefálico/diagnóstico por imagen , Edema Encefálico/fisiopatología , Arteria Carótida Interna/diagnóstico por imagen , Arteria Carótida Interna/fisiopatología , Etnicidad , Femenino , Humanos , Masculino , Arteria Cerebral Media/diagnóstico por imagen , Arteria Cerebral Media/fisiopatología , Tibet , Arteria Vertebral/diagnóstico por imagen , Arteria Vertebral/fisiopatología , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA