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1.
Chemistry ; 29(1): e202202658, 2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36210474

RESUMEN

The electrochemical sensing is a potential method for detection of trace toxic substance. Herein, the heterojunction of netlike ZnO/BiOCl nanosheets was constructed for the enhanced electrochemical detection of ammonia. Cyclic voltammetry and linear sweep voltammetry were used to investigate the electrochemical performance. The results show that the ZnO/BiOCl-modified electrode exhibits higher sensitivity towards ammonia compared with the ZnO and BiOCl-based electrodes, which is ascribed to band structure and fast electron transfer. The high response of 11.8 µA mM-1 and a low detection limit (LOD) of 0.25 µM are achieved. In addition, the ZnO/BiOCl material exhibits high selectivity, repeatability and stability. The better linear relationship between concentration and current (R2 =0.99) is significant for quantitative detection of ammonia, implying that netlike ZnO/BiOCl nanosheets can serve as electrochemical sensing platform for detecting toxic substance. This research provides a strategy for fabricating two-dimensional netlike materials and regulating heterojunctions used for electrochemical application.


Asunto(s)
Aminas , Óxido de Zinc , Óxido de Zinc/química , Amoníaco , Electrodos
2.
Acta Pharmacol Sin ; 43(2): 330-341, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33833407

RESUMEN

Stratifin (SFN) is a member of the 14-3-3 family of highly conserved soluble acidic proteins, which regulates a variety of cellular activities such as cell cycle, cell growth and development, cell survival and death, and gene transcription. Acute kidney injury (AKI) is prevalent disorder characterized by inflammatory response, oxidative stress, and programmed cell death in renal tubular epithelial cells, but there is still a lack of effective therapeutic target for AKI. In this study, we investigated the role of SFN in AKI and the underlying mechanisms. We established ischemic and nephrotoxic AKI mouse models caused by ischemia-reperfusion (I/R) and cisplatin, respectively. We conducted proteomic and immunohistochemical analyses and found that SFN expression levels were significantly increased in AKI patients, cisplatin- or I/R-induced AKI mice. In cisplatin- or hypoxia/reoxygenation (H/R)-treated human proximal tubule epithelial cells (HK2), we showed that knockdown of SFN significantly reduced the expression of kidney injury marker Kim-1, attenuated programmed cell death and inflammatory response. Knockdown of SFN also significantly alleviated the decline of renal function and histological damage in cisplatin-caused AKI mice in vivo. We further revealed that SFN bound to RIPK3, a key signaling modulator in necroptosis, to induce necroptosis and the subsequent inflammation in cisplatin- or H/R-treated HK2 cells. Overexpression of SFN increased Kim-1 protein levels in cisplatin-treated MTEC cells, which was suppressed by RIPK3 knockout. Taken together, our results demonstrate that SFN that enhances cisplatin- or I/R-caused programmed cell death and inflammation via interacting with RIPK3 may serve as a promising therapeutic target for AKI treatment.


Asunto(s)
Proteínas 14-3-3/metabolismo , Lesión Renal Aguda/metabolismo , Isquemia/metabolismo , Enfermedades Renales/metabolismo , Necroptosis , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Animales , Modelos Animales de Enfermedad , Técnicas de Silenciamiento del Gen , Humanos , Túbulos Renales/metabolismo , Ratones , Reacción en Cadena en Tiempo Real de la Polimerasa
3.
Inorg Chem ; 60(20): 15543-15556, 2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-34596403

RESUMEN

A variety of lithiated calix[n]arenes, for which n = 6 or 8, have been isolated, structurally characterized, and evaluated as catalysts for the ring-opening polymerization (ROP) of the cyclic esters ε-caprolactone (ε-CL), δ-valerolactone (δ-VL), and rac-lactide (r-LA). In particular, interaction of p-tert-butylcalix[6]areneH6 (L6H6) with LiOtBu in THF led to the isolation of [Li14(L6H)2(CO3)2(THF)6(OH2)6]·14THF (1·14THF), the core of which has a chain of five Li2O2 diamonds. Similar use of p-tert-butylcalix[8]areneH8 (L8H8) afforded [Li10(L8)(OH)2(THF)8]·7THF (2·7THF), where the core is composed of a six-rung Li-O ladder. Use of debutylated calix[8]areneH8 (deBuL8H8) led to an elongated dimer [Li18(deBuL8)2(OtBu)2(THF)14]·4THF (3·4THF) in which the calix[8]arenes possess a wavelike conformation forming bridges to link three separate LixOy clusters (where x and y = 6, ignoring the THF donor oxygens). Interaction of L8H8 with LiOH·H2O afforded [Li4(L8H4)(OH2)4(THF)6]·5.5THF (4·5.5THF), where intramolecular H-bond interactions involving Li, O, and H construct a cage in the core of the structure with six- and eight-membered rings. Lastly, addition of Me3Al to the solution generated from L8H8 and LiOtBu led to the isolation of [(AlMe2)2Li20(L8H2)2(OH2)4(O2-)4(OH)2(NCMe)12]·10MeCN (5·10MeCN) in which Li, O, Al, and N centers build a polyhedral core. These complexes have been screened for their potential to act as precatalysts in the ring-opening polymerization (ROP) of ε-CL, δ-VL, and r-LA. For the ROP of ε-CL, δ-VL, and r-LA, systems 1-4 exhibited moderate activity at 130 °C over 8 h. In the case of ROP using the mixed-metal (Li/Al) system 5, better conversions and high molecular weight polymers were achieved. In the case of the ROP of ω-pentadecalactone (ω-PDL), the systems proved to be inactive under the conditions employed herein.

4.
J Nat Prod ; 84(2): 327-338, 2021 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-33439652

RESUMEN

Three new cyclopeptides with serial Phe residues were identified with the aid of HPLC-DAD analysis, from the culture broth of Cladobotryum varium, a fungal pathogen causing mushroom cobweb disease. Cladoamides A (1) and B (2) have two consecutive N-methylphenylalanine units in the destruxin class cyclic depsipentapeptide framework, while cladoamide C (3) has a three consecutive Phe motif in a cyclopentapeptide structure. Of these three cyclopeptides, 1 showed potent autophagy-inducing activity at 10 µg/mL, comparable to a positive control, rapamycin. For the determination of the absolute configurations of the Ile residues in 1 and 3, new conditions for separating Ile and allo-Ile, using a pentafluorophenyl-bonded solid phase and methanolic solvent, were established within the analytical scheme of the advanced Marfey's method, thus offering a convenient alternative to the C3 Marfey's method, which requires elution with a three-solvent mixture. The sequence of two d-Phe and one l-Phe in 3 was determined through NMR chemical shift prediction by DFT-based calculations and chemical synthesis, which demonstrated the significance of noncovalent interactions in the accurate calculation of stable conformers for peptides with multiple aromatic rings.


Asunto(s)
Hypocreales/química , Péptidos Cíclicos/química , Agaricales , Hypocreales/patogenicidad , Japón , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Péptidos Cíclicos/aislamiento & purificación , Metabolismo Secundario
5.
Phytother Res ; 35(11): 6401-6416, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34585457

RESUMEN

Although renal fibrosis is a common complication of chronic kidney disease (CKD), effective options for its treatment are currently limited. In this study, we evaluated the renal protective effect and possible mechanism of eleutheroside B. In order to solve the allergic reactions, side effects, and low oral bioavailability of eleutheroside B, we successfully prepared PLGA (poly [lactic-co-glycolic acid])-eleutheroside B nanoparticles (NPs) with the diameter of about 128 nm. In vitro and in vivo results showed that eleutheroside B could inhibit expression levels of α-smooth muscle actin (α-SMA) and collagen I. Molecular docking results showed that eleutheroside B bound to Smad3 and significantly decreased the expression of phospho-Smad3 (p-Smad3). Silencing Smad3 reversed the fibrotic protective effect of eleutheroside B in HK2 cells. Furthermore, small animal imaging showed that NPs can selectively accumulate in the UUO kidneys of mice, and retention time reached as long as 7 days. In conclusion, our results suggested that eleutheroside B is a potential drug to protect renal fibrosis and PLGA-eleutheroside B NPs could facilitate specific targeted therapy for renal fibrosis.


Asunto(s)
Fibrosis , Enfermedades Renales , Nanopartículas , Animales , Glucósidos , Glicolatos , Enfermedades Renales/tratamiento farmacológico , Ratones , Simulación del Acoplamiento Molecular , Fenilpropionatos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Proteína smad3
6.
Int J Food Sci Nutr ; 70(7): 825-833, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30907199

RESUMEN

The phytochemicals in the peel of six oranges and ten mandarins including seven wild varieties and three cultivars were systematically characterised using UHPLC-Q-TOF-MS, and the correlation analysis was performed between phytochemicals and antioxidant capacity in order to investigate the phytochemical contributors to antioxidant capacity. The gradient elution was completed within 16 min and 92 compounds were undoubtedly or tentatively identified. Furthermore, the antioxidant capacities were determined using ABTS, DPPH and FRAP methods. The number of compounds, their contents and the antioxidant capacities were sequenced in the same order of the wild mandarins > cultivated mandarins > oranges. The correlation analysis that showed five compounds were significantly correlated with the antioxidant capacity and can act as main contributors to the citrus varieties with high antioxidant capacities. This study is systematic for the metabolites identification of mandarins and oranges and provides valuable information for effective utilisation of citrus peel and their bioactive compounds.


Asunto(s)
Antioxidantes/análisis , Citrus sinensis/química , Citrus/química , Fitoquímicos/análisis , Citrus/clasificación , Citrus sinensis/clasificación , Análisis de los Alimentos , Frutas/química , Valor Nutritivo , Extractos Vegetales/análisis , Espectrometría de Masas en Tándem
7.
Cancer Cell Int ; 18: 106, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30065619

RESUMEN

BACKGROUND: Cajal body (CB) is a nucleic organelle where small nuclear ribonucleoproteins undergo modification, maturation, splicing and/or assembly. Coilin is the marker structural protein of CBs. The expression level and cellular localization of coilin is sensitive to chemotherapeutic reagents, such as cisplatin. The gene of cyclin-dependent kinase inhibitor 1B (p27) is located with a high incidence translocation region of leukemic chromosomes, and its expression was of prognosis values in a variety of adult leukemia types. The exact profile and associated functions of coilin, as well as p27, in children's acute lymphoblastic leukemia (ALL) is obscure. METHODS: Bone marrow samples from 144 patients with ALL were collected. The expression levels of coilin and p27 were detected by qRT-PCR. The patient cohort was divided into low and high groups of coilin and p27 respectively. The prognosis and clinicobiological characteristics of different groups were investigated, especially focused on the treatment outcome. Leukemia cells of Reh or RS4;11 were exposed to different concentrations of DNR, prior to the detection for morphological changes of coilin by immunofluorescence. In Reh cells, lentivirus sh-coilin was used to silence coilin expression. Western blotting was used to detect coilin and p27 expression; flow cytometry was used for cell cycle and apoptosis assay; MTS method was used for measuring cell viability to examine the drug sensitivity of DNR. RESULTS: In this study, we found that daunorubicin was able to induce significant morphological changes of CBs in Reh and RS4;11 cells. Knockdown the expression of coilin increased the sensitivity to daunorubicin and inhibited the expression of p27 in Reh cells, and led to increased apoptosis. Importantly, not only the levels of coilin and p27 mRNA expression at initial diagnosis ALL children are markedly higher than those at complete remission (CR), but also both coilin and p27 expression in the relapsed patients was observed significantly higher comparing to the continuous CR patients. The 4-year EFS and RFS indicated that low levels of both coilin and p27 group favored better prognosis (p < 0.05). CONCLUSIONS: Our results indicated that consideration of coilin and p27 levels could be a prognostic reference for predicting the outcome of pediatric ALL patients, especially for disease recurrence. Reduction of coilin expression was sufficient to increase the sensitivity of leukemic cells to daunorubicin treatments, and during which possibly involved functions of p27 in cell cycle regulation and its effects on cell apoptosis.

8.
J Sep Sci ; 41(9): 1947-1959, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29370467

RESUMEN

An efficient ultra high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry method was developed for separation and profiling of phytochemical constituents of Chinese wild mandarin Mangshanju (Citrus reticulata Blanco). All constituents were well separated within 16 min. Based on retention times, accurate mass, MSE fragments, and/or reference standards as well as databases, a total of 81 compounds were unambiguously identified or tentatively assigned including flavonoid glycosides, acylated flavonoid glycosides, flavones, polymethoxylated flavonoids, and limonoids as well as four other compounds. Among them, 22 polymethoxylated flavones and ten polymethoxylated flavanones/chalcones were identified in Mangshanju, more types than other citrus reported before. A basic procedure for identifying flavonoid-O-glycosides and the aglycones including polymethoxylated flavonoids was proposed. In addition, this method was successfully used to analyze another four mandarin germplasms, Cenxi suan ju, Xipi gousi gan, Nanfeng miju, and Or, showing that Mangshanju contained two characteristic compounds distinct from the other four citrus species. This study systematically profiled phytochemical constituents of Mangshanju, which was helpful for further utilization of Mangshanju owing to its abundant bioactive compounds.


Asunto(s)
Citrus/química , Fitoquímicos/química , China , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/química , Flavanonas/análisis , Flavonas/análisis , Flavonoides/análisis , Glicósidos/análisis , Limoninas/análisis , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem
9.
Yi Chuan ; 40(8): 657-667, 2018 Aug 16.
Artículo en Zh | MEDLINE | ID: mdl-30117421

RESUMEN

Peroxisome proliferator-activated receptor gamma (PPARγ) is a critical regulator of adipogenesis. Our previous study showed that unlike human and mouse PPARγ transcripts, several chicken PPARγ transcript variants contain upstream open reading frames (uORFs) in their 5'untranslated region (5'TR). To decipher the role of uORFs in post-transcriptional regulation of chicken PPARγ gene, we constructed wild-type (psiCHECK2-cPPARγ3-5'UTR-WT) and a uORF mutant (the upstream ATG (uATG) was mutated to stop codon TGA) 5'UTR reporters (psiCHECK2-cPPARγ3- 5'UTR-Mut) of chicken PPARγ transcript variant 3 (cPPARγ3). These two reporters were individually transfected into immortalized chicken pre-adipocytes (ICPA) and DF1 cells, and the renilla luciferase (hRluc) activity and mRNA expression level were detected by reporter assay and qRT-PCR. The results showed that the hRluc activity of the mutated 5'UTR was significantly higher than that of the wild-type 5'UTR in ICPA cells (P<0.01), and the hRluc activity of the mutated 5'UTR tended to be higher than that of the wild-type 5'UTR in DF1 cells, but this difference did not reach statistical significance (P>0.05). The qRT-PCR analysis showed, in ICPA cells, the hRluc mRNA expression was significantly lower in the cells transfected with the mutated 5'UTR construct than in the cells transfected with the wild-type 5'UTR construct (P<0.01). In DF1 cells, the hRluc mRNA expression tended to be lower in the cells transfected with the mutated 5'UTR construct than in the cells transfected with the wild-type 5'UTR construct, but this difference did not reach statistical significance (P>0.05). To further gain insight into the post-transcriptional regulation of cPPARγ3 by the uORF, we constructed the expression plasmids bearing the full-length coding region of chicken PPARγ gene plus either wild-type or mutant uORF 5'UTR (pcDNA3.1-cPPARγ3-WT and pcDNA3.1-cPPARγ3-Mut). These two constructed PPARγ expression plasmids were individually transiently transfected into both ICPA and DF1 cells, and PPARγ mRNA and protein levels were assayed by qRT-PCR and western blotting. The result showed that in both cell lines, PPARγ mRNA expression was significantly lower in the cells transfected with pcDNA3.1-cPPARγ3-Mut than in the cells transfected with pcDNA3.1-cPPARγ3-WT (P<0.05). In contrast, western blot analysis showed that PPARγ protein level was significantly higher in the cells transfected with pcDNA3.1-cPPARγ3-Mut than in the cells transfected with pcDNA3.1-cPPARγ3-WT (P<0.001). Taken together, our results demonstrate that the uORF in 5'UTR of the cPPARγ3 inhibits its translation.


Asunto(s)
Regiones no Traducidas 5' , Regulación de la Expresión Génica , PPAR gamma/genética , Transcripción Genética , Animales , Línea Celular , Pollos , Sistemas de Lectura Abierta , PPAR gamma/metabolismo , Plásmidos/genética , Plásmidos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transfección
10.
Cancer Cell Int ; 17: 43, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28367105

RESUMEN

BACKGROUND: MYCN gene amplification is related to risk stratification. Therefore it is important to identify accurately the level of the MYCN gene as early as possible in neuroblastoma (NB); however, for patients with bone marrow (BM) metastasis who need chemotherapy before surgery, timely detection of the MYCN gene is not possible due to the unavailability of primary tumors. METHODS: MYCN gene status was evaluated in 81 BM metastases of NB by interphase fluorescence in situ hybridization (FISH) analysis of BM cells. The clinicobiological characteristics and prognostic impact of MYCN amplification in NB metastatic to BM were analyzed. RESULTS: MYCN amplification was found in 16% of patients with metastases, and the results were consistent with the primary tumors detected by pathological tissue FISH. MYCN amplification was associated with age, lactate dehydrogenase (LDH) levels and prognosis (P = 0.038, P < 0.001, P = 0.026). Clinical outcome was poorer in patients with MYCN amplification than in those without amplification (3-year EFS 28.8 ± 13.1 vs. 69.7 ± 5.7%, P = 0.005; 3-year OS 41.5 ± 14.7 vs. 76.7 ± 5.5%, P = 0.005). CONCLUSIONS: MYCN amplification predicts a poor outcome in NB metastatic to BM, and interphase FISH of bone marrow cells provides a timely direct and valid method to evaluate the MYCN gene status.

11.
BMC Anesthesiol ; 17(1): 13, 2017 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-28122491

RESUMEN

BACKGROUND: Perioperative allogenic transfusion is required in almost 50% of patients undergoing cardiac surgery and is associated with higher risk of mortality and morbidity (Xue et al., Lancet 387:1905, 2016; Ferraris et al., Ann Thorac Surg 91:944-82, 2011). Acute normovolemic hemodilution (ANH) is recommended as a potential strategy during cardiac surgery, but the blood conservation effect and the degree of ANH was still controversial. There is also an increasing concern about the improved outcomes associated with ANH. Therefore, a better understanding of the effect of mild volume ANH during cardiac surgery is urgently needed. METHODS: This retrospective study included 2058 patients who underwent cardiac surgery between 2010 and 2015. The study population was split into two groups (with and without mild volume ANH). Propensity score adjustment analysis was applied. We reported the association between the use of mild volume ANH and perioperative outcomes. RESULTS: A total of 1289 patients were identified. ANH was performed in 358 patients, and the remaining 931 patients did not receive any ANH. Five hundred of the total patients (38.8%) received perioperative RBC transfusions, 10% (129/1289) of patients received platelet, and 56.4% (727/1289) of patients received fresh frozen plasma transfusions. Mild volume ANH administration was significantly associated with decreased intraoperative RBC transfuse rate (8.5% vs. 14.4%; p = 0.013), number of RBC units (p = 0.019), and decreased postoperative pulmonary infection (6.8 vs. 11.3%; p = 0.036) during cardiac surgery. However, there was no significant difference regarding intraoperative fresh frozen plasma (FFP) and platelet concentrate transfusions, as well as postoperative and total perioperative allogeneic transfusions. Furthermore, there was no significant difference regarding postoperative outcomes including mortality, prolonged wound healing, stroke, atrial fibrillation, reoperation for postoperative bleeding and acute kidney injury. There was also no difference in postoperative ventilation time, length of ICU and hospital stay. CONCLUSION: Based on the 5-year experience of mild volume ANH in cardiac surgeries with CPB in our large retrospective cohort, mild volume ANH was associated with decreased intraoperative RBC transfusion and postoperative pulmonary infection in Chinese patients undergoing cardiac surgery. However, there was no significant difference regarding postoperative and total perioperative allogeneic transfusions.


Asunto(s)
Transfusión Sanguínea/estadística & datos numéricos , Hemodilución/métodos , Enfermedades Pulmonares/epidemiología , Procedimientos Quirúrgicos Cardíacos , China/epidemiología , Femenino , Humanos , Periodo Intraoperatorio , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos
12.
Yi Chuan ; 39(11): 1066-1077, 2017 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-29254924

RESUMEN

Peroxisome proliferator-activated receptor gamma (PPARγ) is the master regulator of adipogenesis and adipose tissue development. It also plays crucial roles in many other biological processes, including lipid and glucose metabolism and energy homeostasis. Recently, evidence has been accumulating that the PPARγ gene is not only genetically regulated, but also epigenetically regulated by DNA methylation, histone modification, non-coding RNA and chromosome remodeling. In this review, we summarize the advances in the genetic and epigenetic regulation of the PPARγ gene during adipogenesis, and discuss future research directions and trends for the study of its regulation.


Asunto(s)
Adipogénesis , Metilación de ADN , PPAR gamma/genética , Animales , Ensamble y Desensamble de Cromatina , Histonas/metabolismo , Humanos , Polimorfismo de Nucleótido Simple
13.
Zhongguo Zhong Yao Za Zhi ; 42(7): 1281-1286, 2017 Apr.
Artículo en Zh | MEDLINE | ID: mdl-29052387

RESUMEN

Cordyceps sinensis is a Chinese unique precious herbal material, its genuine producing areas covering Naqu, Changdu in Qinghai Tibet Plateau, Yushu in Qinghai province and other regions. In recent 10 years, C. sinensis resources is decreasing as a result of the blindly and excessively perennial dug. How to rationally protect, develop and utilize of the valuable resources of C. sinensis has been referred to an important field of research on C. sinensis. The ecological environment and climate change trend of Qinghai Tibet plateau happens prior to other regions, which means that the distribution and evolution of C. sinensis are more obvious and intense than those of the other populations. Based on RS (remote sensing)/GIS(geographic information system) technology, this paper utilized the relationship between the snowline elevation, the average temperature, precipitation and sunshine hours in harvest period (April and may) of C. sinensis and the actual production of C. sinensis to establish a weighted geometric mean model. The model's prediction accuracy can reach 82.16% at least in forecasting C. sinensis year yield in Naqu area in every early June. This study can provide basic datum and information for supporting the C. sinensis industry healthful, sustainable development.


Asunto(s)
Cambio Climático , Cordyceps/crecimiento & desarrollo , Conservación de los Recursos Naturales , Luz Solar , Temperatura , Tibet , Tiempo (Meteorología)
14.
Plant Mol Biol ; 91(1-2): 115-30, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26869262

RESUMEN

Superoxide dismutase (SOD) is believed to enhance abiotic stress resistance by converting superoxide radical (O2 (-)) to H2O2 to lower ROS level and maintain redox homeostasis. ROS level is controlled via biphasic machinery of ROS production and scavenging. However, whether the role of SOD in abiotic stress resistance is achieved through influencing the biophasic machinery is not well documented. Here, we identified a wheat copper-zinc (Cu/Zn) SOD gene, TaSOD2, who was responsive to NaCl and H2O2. TaSOD2 overexpression in wheat and Arabidopsis elevated SOD activities, and enhanced the resistance to salt and oxidative stress. TaSOD2 overexpression reduced H2O2 level but accelerated O2 (-) accumulation. Further, it improved the activities of H2O2 metabolic enzymes, elevated the activity of O2 (-) producer NADPH oxidase (NOX), and promoted the transcription of NOX encoding genes. The inhibition of NOX activity and the mutation of NOX encoding genes both abolished the salt resistance of TaSOD2 overexpression lines. These data indicate that Cu/Zn SOD enhances salt resistance, which is accomplished through modulating redox homeostasis via promoting NOX activity.


Asunto(s)
Regulación Enzimológica de la Expresión Génica/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , NADPH Oxidasas/metabolismo , Cloruro de Sodio/toxicidad , Superóxido Dismutasa/metabolismo , Triticum/enzimología , Secuencia de Aminoácidos , Homeostasis , Peróxido de Hidrógeno/metabolismo , NADPH Oxidasas/genética , Oxidación-Reducción , Filogenia , Especies Reactivas de Oxígeno/metabolismo , Estrés Fisiológico , Superóxido Dismutasa/genética , Triticum/efectos de los fármacos , Triticum/genética , Triticum/metabolismo
15.
Chin J Traumatol ; 19(4): 187-92, 2016 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-27578372

RESUMEN

In this review, we focused on a few obstacles that hinder three-dimensional (3D) bioprinting process in tissue engineering. One of the obstacles is the bioinks used to deliver cells. Hydrogels are the most widely used bioink materials; however, they aremechanically weak in nature and cannot meet the requirements for supporting structures, especially when the tissues, such as cartilage, require extracellular matrix to be mechanically strong. Secondly and more importantly, tissue regeneration is not only about building all the components in a way that mimics the structures of living tissues, but also about how to make the constructs function normally in the long term. One of the key issues is sufficient nutrient and oxygen supply to the engineered living constructs. The other is to coordinate the interplays between cells, bioactive agents and extracellular matrix in a natural way. This article reviews the approaches to improve the mechanical strength of hydrogels and their suitability for 3D bioprinting; moreover, the key issues of multiple cell lines coprinting with multiple growth factors, vascularization within engineered living constructs etc. were also reviewed.


Asunto(s)
Bioimpresión , Ingeniería de Tejidos , Animales , Línea Celular , Humanos , Hidrogeles , Nanopartículas
16.
Yi Chuan ; 38(8): 724-35, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27531611

RESUMEN

miR-17-92 cluster plays important roles in cell proliferation, differentiation, apoptosis, animal development and tumorigenesis. The transcriptional regulation of miR-17-92 cluster has been extensively studied in mammals, but not in birds. To date, avian miR-17-92 cluster genomic structure has not been fully determined. The promoter location and sequence of miR-17-92 cluster have not been determined, due to the existence of a genomic gap sequence upstream of miR-17-92 cluster in all the birds whose genomes have been sequenced. In this study, genome walking was used to close the genomic gap upstream of chicken miR-17-92 cluster. In addition, bioinformatics analysis, reporter gene assay and truncation mutagenesis were used to investigate functional role of the genomic gap sequence. Genome walking analysis showed that the gap region was 1704 bp long, and its GC content was 80.11%. Bioinformatics analysis showed that in the gap region, there was a 200 bp conserved sequence among the tested 10 species (Gallus gallus, Homo sapiens, Pan troglodytes, Bos taurus, Sus scrofa, Rattus norvegicus, Mus musculus, Possum, Danio rerio, Rana nigromaculata), which is core promoter region of mammalian miR-17-92 host gene (MIR17HG). Promoter luciferase reporter gene vector of the gap region was constructed and reporter assay was performed. The result showed that the promoter activity of pGL3-cMIR17HG (-4228/-2506) was 417 times than that of negative control (empty pGL3 basic vector), suggesting that chicken miR-17-92 cluster promoter exists in the gap region. To further gain insight into the promoter structure, two different truncations for the cloned gap sequence were generated by PCR. One had a truncation of 448 bp at the 5'-end and the other had a truncation of 894 bp at the 3'-end. Further reporter analysis showed that compared with the promoter activity of pGL3-cMIR17HG (-4228/-2506), the reporter activities of the 5'-end truncation and the 3'-end truncation were reduced by 19.82% and 60.14%, respectively. These data demonstrated that the important promoter region of chicken miR-17-92 cluster is located in the -3400/-2506 bp region. Our results lay the foundation for revealing the transcriptional regulatory mechanisms of chicken miR-17-92 cluster.


Asunto(s)
Pollos/genética , MicroARNs/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Animales , Secuencia de Bases , Clonación Molecular/métodos , Regulación de la Expresión Génica/genética , Genes Reporteros/genética , Regiones Promotoras Genéticas/genética , Alineación de Secuencia , Análisis de Secuencia de ADN/métodos , Transcripción Genética/genética
17.
BMC Genomics ; 16: 807, 2015 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-26476565

RESUMEN

BACKGROUND: Allopolyploid genome needs wide structural variation to deal with genomic shock. The introgression line, generated via asymmetric somatic hybridization, is introgressed with a minimum of exogenous chromatin, which also leads to genomic shock to induce genetic variation. However, the extent of its genomic variation and its difference from allopolyploidies remains unknown. METHODS: Here, we explored this issue using the bread wheat cultivar SR3, a derivative of an asymmetric somatic hybrid between the cultivar JN177 and an accession of tall wheatgrass (Thinopyrum elongatum). The ESTs (expressed sequence taqs) were large-scale sequenced using the cDNA library constructed in each of SR3 and JN177. Point mutations and indels (insertions and deletions) of SR3 were calculated, and their difference from the genetic variation of bread wheat and its ancestors were compared, with aim to analyze the extent and pattern of sequence variation induced by somatic hybridization. RESULTS: Both point mutations and indels (insertions and deletions) were frequently induced by somatic hybridization in the coding sequences. While the genomic shock caused by allopolyploidization tends to favor deletion over insertion, there was no evidence for such a preference following asymmetric somatic hybridization. The GC content of sequence adjacent to indel sites was also distinct from what has been observed in allopolyploids. CONCLUSIONS: This study demonstrates that asymmetric somatic hybridization induces high frequency of genetic variation in a manner partially different from allopolipoidization. Asymmetric somatic hybridization provides appropriate material to comprehensively explore the nature of the genetic variation induced by genomic shock.


Asunto(s)
Mutación INDEL/genética , Mutación Puntual/genética , Triticum/genética , Pan , Cromatina/genética , Etiquetas de Secuencia Expresada , Biblioteca de Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Cariotipificación , Datos de Secuencia Molecular
18.
BMC Genomics ; 16: 888, 2015 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-26518334

RESUMEN

BACKGROUND: Toxoplasma gondii is an intracellular protozoan that affects most species of endothermic animals including humans with a great infection rate. The vertical transmission of T. gondii causes abortion, constituting a serious threat to humans and leading to great losses in livestock production. Distinct from population structure of T. gondii in North America and Europe, Chinese 1 (ToxoDB #9) is a dominant genotype prevalent in China. Among the isolates of Chinese 1, the Wh3 and Wh6 have different virulence and pathogenicity in mice. However, little has been known about their difference at the genomic level. Thus the next-generation sequencing (NGS) approach was used to discover the association of the phenotypical variations with the genome sequencing data and the expression and polymorphisms of the key effectors. RESULTS: We successfully sequenced the genome of Chinese 1 strains of Wh3 and Wh6. The average sequencing depths were 63.91 and 63.61 for Wh3 and Wh6, respectively. The variations of both isolates were identified in comparison with reference genome of type I GT1 strain. There were 505,645 and 505,856 SNPs, 30,658 and 30,004 indels, 4661 and 2320 SVs, and 1942 and 3080 CNVs for Wh3 and Wh6, respectively. In target search variations of particular factors of T. gondii, the dense granule protein 3 (GRA3) and rhoptry neck protein 3 (RON3) were found to have 35 SNPs, 2 indels and 89 SNPs, 6 indels, respectively. GRA3 and RON3 were both found to have higher expression levels in less virulent Wh6 than in virulent Wh3. Both strains of type Chinese 1 share polymorphic GRA15II and ROPI/III with type I, II, and III strains. CONCLUSIONS: Sequencing of the two strains revealed that genome structure of Chinese 1 and type I strains has considerable genomic variations. Sequencing and qRT-PCR analyses of 26 effectors displayed a remarkable variation that may be associated with phenotype and pathogenic differences.


Asunto(s)
Variación Genética , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Toxoplasma/genética , Animales , China , Biología Computacional/métodos , Femenino , Genoma de Protozoos , Humanos , Mutación INDEL , Anotación de Secuencia Molecular , Polimorfismo de Nucleótido Simple , Reproducibilidad de los Resultados , Toxoplasma/clasificación , Toxoplasma/patogenicidad , Toxoplasmosis Animal/parasitología , Virulencia/genética
19.
Nanomaterials (Basel) ; 14(12)2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38921916

RESUMEN

A series of TiN/ITO composite films with various thickness of ITO buffer layer were fabricated in this study. The enhancement of optical properties was realized in the composite thin films. The absorption spectra showed that absorption intensity in the near-infrared region was obviously enhanced with the increase of ITO thickness due to the coupling of surface plasma between TiN and ITO. The epsilon-near-zero wavelength of this composite can be tuned from 935 nm to 1895 nm by varying the thickness of ITO thin films. The nonlinear optical property investigated by Z-scan technique showed that the nonlinear absorption coefficient (ß = 3.03 × 10-4 cm/W) for the composite was about 14.02 times greater than that of single-layer TiN films. The theoretical calculations performed by finite difference time domain were in good agreement with those of the experiments.

20.
Heliyon ; 10(4): e26271, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38375280

RESUMEN

Background: An evident association between mood disorders and TMJ dysfunction has been demonstrated in previous studies. This study observed both the behavioral changes and the pathological changes in hippocampal tissue of rats in an animal model of TMJ-OA by injecting MIA into TMJ. Methods: Eighteen SD rats were randomly assigned to the NC group and the MIA groups. A TMJ-OA model was established to assess the HWT in the TMJ region, and the rats were subjected to the OFT and EPM. HE, O-fast green staining, qRT-PCR and immunofluorescence were used to detect condylar damage. Serum and hippocampal oxidative stress levels were detected. Functions of genes obtained by RNA-Seq were investigated using H2O2, ZnCl2 and transfection of siRNA on HT22 cells. Results: Injection of MIA resulted in disorganization of the chondrocyte layer on the condylar surface of rats, with reduced synthesis and increased degradation of the condylar cartilage matrix and reduced HWT. The results of the OFT and EPM showed that the rats in the MIA group developed anxiety-like behavior during the sixth week of MIA injection. Increased Nox4 expression, decreased SOD2 expression, elevated MDA level, and reduced GSH level were detected in serum and hippocampal neurons in the MIA group, with nuclear pyknosis and reduced Nissl bodies observed in neurons. The expression of Slc39a12 in hippocampal neurons of rats in the MIA group decreased. Slc39a12 knockdown in HT22 cells induced increased Nox4 expression, decreased SOD2 expression, increased MDA level, and reduced GSH and intracellular Zn2+. Oxidative stress in HT22 cells after transfection and H2O2 stimulation was reversed when ZnCl2 was added. Conclusion: Loss of Slc39a12 in hippocampal neurons results in cellular oxidative stress, further leading to neuronal damage. This may potentially explain how TMJ-OA triggers anxiety-like behavior in rats.

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