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1.
Ecotoxicol Environ Saf ; 208: 111638, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396158

RESUMO

The flame retardant decabrominated diphenyl ether (BDE-209) is a widely used chemical in a variety of products and exists extensively in the environment. BDE-209 has been reported to induce kidney injury and dysfunction. However, the causes and mechanisms of its nephrotoxicity are still under investigation. In this study, 150 male broilers were exposed to BDE-209 concentrations of 0, 0.004, 0.04, 0.4, 4.0 g/kg for 42 days. The relative kidney weight, histopathology, markers of renal injury, oxidative stress, inflammation, apoptosis and the expression of MAPK signaling pathways-related proteins were assessed. The results showed that the concentrations of blood urea nitrogen (BUN), creatinine (CRE) and the neutrophil gelatinase-associated lipocalin (NGAL), significantly increased after exposure to BDE-209 with the doses more than 0.04 g/kg. Similarly, severe damage of renal morphology was observed, including atrophy and necrosis of glomeruli, and swelling and granular degeneration of the renal tubular epithelium. In the renal homogenates, the oxidative stress was evidenced by the elevated concentrations of MDA and NO, and decreased levels of GSH-Px, GSH and SOD. Due to the inflammatory response, the level of NF-κB and the pro-inflammatory cytokines TNF-α, IL-1ß, IL-18 were remarkably upregulated, while the content of the anti-inflammatory cytokine IL-10 decreased. Additionally, the apoptotic analysis showed notable upregulations of Bax/Bcl-2 ratio, the relative expression of p-ERK1/2 and p-JNK1/2, and the expression of Bax, cytochrome c and caspase 3. The present study indicates that BDE-209 exposure can cause nephrotoxicity in broilers through oxidative stress and inflammation, which activate the phosphorylation of key proteins of the MAPK signaling pathways, and subsequently induce mitochondria-mediated kidney apoptosis.


Assuntos
Lesão Renal Aguda/induzido quimicamente , Poluentes Ambientais/toxicidade , Retardadores de Chama/toxicidade , Éteres Difenil Halogenados/toxicidade , Lesão Renal Aguda/metabolismo , Lesão Renal Aguda/patologia , Animais , Apoptose/efeitos dos fármacos , Galinhas , Inflamação/induzido quimicamente , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos
2.
ChemSusChem ; 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33258550

RESUMO

Lithium-sulfur battery (LSB) has become one of the most promising candidates for next-generation energy storage systems owing to its high theoretical energy density, environmental friendliness, and cost-effectiveness. However, its real-word applications are seriously restricted by its undesirable shuttle effect and lithium (Li) dendrite formation. In essence, uncontrollable anion transport is a key factor that causes both polysulfide shuttling and dendrite formation, which creates the possibility of simultaneously addressing the two critical issues in LSBs. An effective strategy to control anion transport is the construction of cation-selective separators. A significant progress has been achieved in the inhibition of the shuttle effect, whereas addressing the problem of Li dendrite formation by utilizing a cation-selective separator is still underway. From this viewpoint, this review analyzes the critical issues with regard to the shuttle effect and Li dendrite formation caused by uncontrollable anion transport, based on which the roles and advantages of cation-selective separators toward high-performance LSBs are presented. According to the separator construction principle, the latest advances and progress in cation-selective separators in inhibiting the shuttle effect and Li dendrite formation are reviewed in detail. Finally, some challenges and prospects are proposed for the future development of cation-selective separators. This review is anticipated to provide a new perspective for simultaneously addressing the two critical issues in LSBs.

3.
Infect Drug Resist ; 13: 4155-4166, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33244245

RESUMO

Objective: There is a paucity of published data to evaluate the efficacy and safety of imipenem (IPM) and piperacillin-tazobactam (PT) dosing regimens in the treatment of septic patients acquiring continuous renal replacement therapy (CRRT). Methods and Materials: Critically-ill patients were grouped into short-stay and long-stay intensive care unit (ICU) patients. Pathogens were isolated from bloodstream infections in these patients. Minimum inhibitory concentration (MIC) value was determined by agar dilution method. Population PK models were introduced in this study, and differences in the likelihood of achieving efficacious and toxic exposures of IPM and PT for critically-ill patients were assessed. Results: A total of 86 K. pneumoniae bloodstream infection associated isolates were collected, and the MIC50 and MIC90 for short-stay ICU patients were 0.5/4 mg/L and 32/128 mg/L, respectively. IMP 0.5g q8h reached 90% probability of target attainment (PTA) against isolates with MICs ≤2 mg/L and was recommended to empirically treat short-stay ICU patients during CRRT based on the target of 40% ƒT>MIC. However, based on a more aggressive target of 100% ƒT>MIC, all the simulated IMP regimens except for IMP 1g q6h failed to achieve >80% cumulative fraction of response (CFR) in such patients. Unfortunately, the risk of drug-related toxicity for IMP 1g q6h was relatively high (50-85%). For PT, even the regimen of 4/0.5g q6h failed to provide sufficient antimicrobial exposure in short-stay ICU patients acquiring CRRT. Conclusion: No dose adjustment was required for the conventional IMP and PT regimens in the critically-ill population acquiring CRRT. Empirical treatment of IMP 0.5g q8h/q6h, not for PT, may provide sufficient antimicrobial exposure for short-stay ICU patients during CRRT. PT should be used in the knowledge of MIC results.

4.
Biomaterials ; : 120276, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32797997

RESUMO

Targeted cell delivery to lesion sites via minimally invasive approach remains an unmet need in regenerative medicine to endow controlled cell distribution and minimized side-effects. Current cell modification approaches to improve cell delivery tend to have adverse effects on cellular phenotype and functionality. Here, we rationally developed a facile and mild cell modification and targeted delivery strategy leveraging endogenous tissue transglutaminase (TGase) expressed on the surface of MSCs (Mesenchymal Stem Cells) and inflammatory endothelial cells (ECs). Cell modification by functional peptides was accomplished simply via TGase catalyzed cross-linking with naturally-expressed MSCs membrane proteins (e.g. Annexin II), without detectable disturbance of cellular viability and functionality. The modified functional peptides could facilitate adhesion of MSCs to inflammatory ECs (with up-regulated TGase expression compared with normal ECs) in vitro, as demonstrated by a one-fold increase of the MSC-EC adhesion force measured by atomic force microscopy (AFM) and by targeted delivery of modified MSC to inflammatory ECs in a flow chamber assay. When transplanted in vivo, modified MSCs demonstrated a dramatic increase in targeted efficiency to inflammatory endothelium compared with non-modified MSCs in both mice ear inflammation and acute/chronic liver injury models. The cell membrane modification strategy and targeted cell delivery mechanism described here can be readily extended for empowering cell engineering and cell therapy with multifaceted functionalities to combat refractory diseases.

5.
Nano Converg ; 7(1): 21, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32542452

RESUMO

Lithium (Li) metal is a promising anode for high-performance secondary lithium batteries with high energy density due to its highest theoretical specific capacity and lowest electrochemical potential among anode materials. However, the dendritic growth and detrimental reactions with electrolyte during Li plating raise safety concerns and lead to premature failure. Herein, we report that a homogeneous nanocomposite protective layer, prepared by uniformly dispersing AlPO4 nanoparticles into the vinylidene fluoride-co-hexafluoropropylene matrix, can effectively prevent dendrite growth and lead to superior cycling performance due to synergistic influence of homogeneous Li plating and electronic insulation of polymeric layer. The results reveal that the protected Li anode is able to sustain repeated Li plating/stripping for > 750 cycles under a high current density of 3 mA cm-2 and a renders a practical specific capacity of 2 mAh cm-2. Moreover, full-cell Li-ion battery is constructed by using LiFePO4 and protected Li as a cathode and anode, respectively, rendering a stable capacity after 400 charge/discharge cycles. The current work presents a promising approach to stabilize Li metal anodes for next-generation Li secondary batteries.

6.
J Colloid Interface Sci ; 575: 61-68, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32361240

RESUMO

Transition metal phosphides have attracted increasing attention as anode materials for sodium-ion batteries (SIBs). Cobalt phosphide (CoP) has been deemed as prospective anode materials owing to its high theoretical capacity. Nevertheless, the defects of cobalt phosphides are evident. Low conductivity, the non-negligible volume expansion and aggregation of particles during sodiation/desodiation process result in poor cycling performance and rapid capacity decay, which greatly limit their applications. Herein, we designed a hollow-nanotube structure of sulfur-doped cobalt phosphide (S-CoP) nanoparticles coated by nitrogen-doped porous carbon (S-CoP@NPC), which can be successfully synthesized via an ordinary hydrothermal process followed by the low-temperature phosphorization/sulfuration treatment. The doping of sulfur element provides more active sites, meanwhile, the carbon coating largely helps to avoid the agglomeration of nanoparticles, alleviate volume expansion and improve the conductivity of materials. The S-CoP@NPC composite presents stable cycling performance, showing a discharge specific capacity of 230 mAh g-1 over 370 cycles at 0.2 A g-1. In addition, it also exhibits good rate capability with a discharge specific capacity of 143 mAh g-1 at 5 A g-1, even when the current density returns to 0.2 A g-1, the discharge specific capacity can recover 213 mAh g-1. Furthermore, the kinetic analysis of S-CoP@NPC composite explains that the excellent cycling and rate performance benefit from the extrinsic pseudocapacitive behavior.

7.
Molecules ; 25(7)2020 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-32235408

RESUMO

In this study, an endo-1,4-ß-xylanase was purified from wheat malt following the procedures of ammonium sulfate precipitation, cation-exchange chromatography, and two-step anion-exchange chromatography. The purified endo-1,4-ß-xylanase had a specific activity of 3.94 u/mg, demonstrating a weight average molecular weight (Mw) of approximately 58,000 Da. After LC-MS/MS (Liquid chromatography-tandem mass spectrometry) identification, the purified enzyme had the highest matching degree with a GH10 (Glycoside Hydrolase 10) domain-containing protein from wheat, there were 23 match peptides with a score above the threshold and the prot-cover was 45.5%. The resulting purified enzyme was used to investigate its degradation ability on high viscosity wheat-derived water-extractable arabinoxylan (WEAX). Degradation experiments confirmed that the purified enzyme was a true endo-acting enzyme, which could degrade large WEAX into smaller WEAX. The average degree of polymerization (avDP) and the viscosity of WEAX decreased with the increasing reaction time. The enzyme could degrade a small amount of WEAX into arabinoxylan-oligosaccharides (AXOS) with a degree of polymerization of 2-6, but no monosaccharide was produced. The degradation occurred rapidly in the first 3.5 h and decreased with the further prolongation of reaction time.

8.
Protein Pept Lett ; 26(5): 332-338, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30816076

RESUMO

BACKGROUND: Arabinoxylan (AX) is the main non-starch polysaccharide in wheat. Wheat malts are traditional raw materials for beer brewing. AX is divided into water-soluble arabinoxylan (WEAX) and waterinsoluble arabinoxylan (WUAX). In the mashing stage of beer production, WUAX in malt is degraded by arabinoxylanase to WEAX, which is further degraded to smaller molecules and retained in the final beer. The viscosity of WEAX is related to its molecular weight. WEAX with higher molecular weight and viscosity can increase viscosity and turbidity and reduce filtration speed of wort and beer; WEAX with moderate molecular weight and viscosity contributes to the foaming characteristics and foam stability, and promotes the taste and texture of a beer; WEAX with small molecular weight has the functions of anti-tumor and lowering blood pressure and is regarded as a prebiotic. Because WEAXs with different molecular weight and properties have different impacts on the beer brewing process and qualities of the final beer, it becomes more important to control the degradation of AX during the brewing process of a beer. Endo-1,4-ß-xylanase (EC 3.2.1.8) is the most important AX degrading enzyme, which cleaves the ß -xylosidic bond between two d-xylopyranosyl residues linked in ß-(1,4). The study of enzymatic properties of endo-1,4-ß-xylanase from wheat malt is very important for the rational formulation of the content and molecular weight of WEAX in wort and beer during the mashing procedure when using wheat malt as the main raw materials. OBJECTIVE: In this article, our motivation is to study the enzymatic properties (including optimum pH and temperature, pH and temperature stability, the effect of inhibitors) of wheat malt endo-1,4-ß-xylanase. METHODS: In this article, we prepared crude enzyme according to the method of Guo with minor modifications. The endo-1,4-ß-xylanase activity was determined according to the method of Biely in the previous report with minor modifications. The 0.5 mL crude enzyme sample was mixed with 0.5 mL 1 mg/mL 4-O-methyl-dglucurono- d-xylan dyed with Remazol Brilliant Blue R (RBBR-Xylan) solution, intensively mixed, and incubated at 40 °C for exactly 90 min. The reaction was stopped by precipitation using 2 mL absolute ethanol, and the reaction mixture was stirred acutely and placed at room temperature for 30 min. Then, the mixture was mixed again and centrifuged at 6000 g for 10 min. The supernatant was collected and the absorbance was measured at 590 nm. Absolute ethanol and RBBR-Xylan were added to the control tubes first, and after the reaction was completed, the crude enzyme sample was added. One unit of endo-1,4-ß-xylanase was defined as at pH 5.5 and 40 °C liberate 1 µmol xylose equivalents in 1 min per g dry wheat malt. RESULTS: The results showed that the optimal activity of endo-1,4-ß-xylanase was achieved at pH 5.5-6.0, and the enzyme was extremely stable at pH 4.5, 5.5 and 6.5 after incubation for 30, 50 and 60 min, respectively. The optimal temperature was 40-45 °C and the deactivation temperature was 75 °C. Endo-1,4-ß-xylanase was stable at 20 °C and 40 °C; the stability was slightly decreased at 50 °C and rapidly decreased at 55 °C. The enzyme activity was mildly inhibited by K+, Na+, and Pb2+, moderately inhibited by Ca2+, Mg2+ and Mn2+ and severely inhibited by Cu2+, Ag+ and EDTA. CONCLUSION: We have got the enzymatic properties of endo-1,4-ß-xylanase from wheat malt, so during wort mashing, we could apply this research result to carry out the rational formulation of the content and molecular weight of WEAX in wort and beer during the mashing procedure when using wheat malt as the main raw materials. Expected to solve the technical problems such as high viscosity, slow filtration speed and so on, but also highlight the typical flavors of WEAX such as rich and persistent foam and mellow texture during the brewing process of a beer.


Assuntos
Endo-1,4-beta-Xilanases/química , Triticum/química , Xilanos/química , Cerveja , Concentração de Íons de Hidrogênio , Hidrólise , Peso Molecular , Plântula/química , Temperatura , Viscosidade
9.
Cancer Cell Int ; 19: 25, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30733646

RESUMO

Background: Increasing studies indicated that circRNAs play critical roles in tumor progression. However, the roles and underlying mechanisms of circRNAs in gastric cancer (GC) remain largely unclear. Methods: Microarray assay was used to screen the abnormally expressed circRNAs in GC. Cell viability assay, transwell assay and in vivo assay were performed to assess the effects of hsa_circ_0081143 on GC cells. Next, interaction between hsa_circ_0081143 and miR-646 was detected by luciferase reporter assay and RNA pull-down assay. Results: High throughput microarray assay showed that hsa_circ_0081143 was upregulated in GC tissues, which was further confirmed by qRT-PCR. Correlation analysis showed that high hsa_circ_0081143 expression was associated with the advanced TNM stage, lymphnode metastases, and poor overall survival of GC patients. Hsa_circ_0081143 inhibition decreased GC cells viability, invasion ability and induced the sensitivity of GC cells to cisplatin (DDP) in vitro. Mechanistically, we showed that hsa_circ_0081143 could act as an endogenous sponge by directly binding to miR-646 and downregulation of miR-646 efficiently reversed the inhibition of CDK6 induced by hsa_circ_008114 knockdown. Additionally, hsa_circ_0081143 silencing suppressed the tumorigenesis and remarkably enhance DDP inhibitory effects of GC cells in vivo. Conclusions: Our study indicated a novel regulatory loop that hsa_circ_0081143/miR-646/CDK6 axis in GC progression. These data suggested that hsa_circ_0081143 might act as a potential novel therapeutic strategy for GC treatment.

10.
J Cell Physiol ; 234(3): 3020-3028, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30132886

RESUMO

Gastric cancer (GC) is one of the leading causes of cancer-related death worldwide. Mounting evidence showed that circular RNAs (circRNAs) play critical roles in human malignancy. However, the knowledge about circRNAs in GC is still unclear. In the current study, high throughput microarray assay showed that circRBMS3 was upregulated in GC tissues, which was further confirmed by quantitative reverse transcription polymerase chain reaction. Correlation analysis revealed that high circRBMS3 expression was associated with advanced TNM stage, depth of invasion, and lymph-node metastasis. Kaplan-Meier analysis indicated that GC patients with high circRBMS3 expression have a poor overall survival (OS). Function assays showed that circRBMS3 silencing reduced GC cells proliferation and invasion in vitro, and inhibited the tumor growth in vivo. Mechanistically, we found that miR-153 could act as a target of circRBMS3. Subsequently, we showed that circRBMS3 promoted snail family zinc finger 1 (SNAI1) expression via inhibiting miR-153 in GC cells. Collectively, these results suggested that circRBMS3 promoted GC cells proliferation and invasion via regulating miR-153/SNAI1 axis.


Assuntos
MicroRNAs/genética , RNA Circular/genética , Fatores de Transcrição da Família Snail/genética , Neoplasias Gástricas/genética , Idoso , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Estadiamento de Neoplasias , Transdução de Sinais
11.
J Colloid Interface Sci ; 532: 352-362, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30096529

RESUMO

SnO2 is considered as one of the most promising alternative anode materials for lithium ion batteries (LIBs) and sodium ion batteries (SIBs) due to high specific capacity, low discharge voltage plateau and environmental friendliness. In this work, 1D ultrafine SnO2 nanorods anchored on 3D graphene aerogel (SnO2 NRs/GA) composite is prepared through a simple reduction-induced self-assembly method in the solution of graphene oxide (GO), Vitamin C and SnO2 nanoparticles. Vitamin C plays an important role in the reduction of GO. The structural and morphological characterizations demonstrate that 1D ultrafine SnO2 nanorods are uniformly and tightly anchored on the surface of 3D graphene nanosheet aerogels. The unique 3D network structure as well as the synergistic effect between 3D graphene nanoshhet and 1D SnO2 nanorods endows the as-prepared SnO2 NRs/GA composite with the good electrochemical lithium/sodium storage performance. It delivers the high initial discharge capacity (1713 mA h g-1 at 0.1 A g-1 for LIBs and 539 mA h g-1 at 0.05 A g-1 for SIBs) and good cycle stability (869 mA h g-1 at 0.1 A g-1 after 50 cycles for LIBs and 232 mA h g-1 at 0.05 A g-1 after 100 cycles for SIBs). Moreover, the SnO2 NRs/GA composite exhibits excellent cycle stability for SIBs with a high reversible capacity of 96 mA h g-1 at as high as 1 A g-1 for 500 cycles. This work provides a simple method to fabricate the electro-active materials-graphene aerogel composites for high-performance LIBs and SIBs.

12.
Viral Immunol ; 30(3): 232-239, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28061318

RESUMO

Hepatitis B virus (HBV) infection is one of the major risk factors leading to the development of hepatocellular carcinoma (HCC). Hepatitis B surface antigen (HBsAg) plays a pivotal role in HBV-related HCC pathogenesis, and Toll-like receptor (TLR) 2 is also considered to mediate tumor progression. However, the interaction between HBsAg and TLR2 in HCC progression remains unclear. Thus, the aim of the study was to explore the effect of HBsAg-TLR2 pathway on growth and invasion of HBV-related HCC cells and examine the potential mechanisms been involved. The expression of TLR2 was measured in two different HCC cell lines (HepG2 and HepG2.2.15) with or without recombinant HBsAg by real-time reverse polymerase chain reaction and Western blot. Cellular proliferation, invasion, cytokine productions, and downstream signaling pathways were also measured in TLR2-silencing HepG2.2.15 cells in response to HBsAg stimulation. The mRNA and protein levels of TLR2 were significantly elevated in HepG2.2.15 cells than those in HepG2 cells. HBsAg simulation increased proinflammatory cytokine production and invasion of HepG2.2.15 cells, while this process was inhibited by TLR2 silence. However, TLR2 siRNA transfection alone did not affect the bioactivities of tumor cells. Moreover, HBsAg increased expression of MyD88 and phosphorylation of NF-κB p50 and p38MAPK. Downregulation of TLR2 inhibited HBsAg-induced MyD88 and p-NF-κB, but not p-p38MAPK in HepG2.2.15 cells. In conclusion, HBsAg stimulation promotes the invasion of HBV-related HCC cells. TLR2/MyD88/NF-κB signaling pathway may be involved in this procession by upregulation of cytokine production. The interaction between TLR2 and HBsAg may contribute to the poor prognosis of HBV-related HCC.


Assuntos
Movimento Celular , Proliferação de Células , Antígenos de Superfície da Hepatite B/metabolismo , Hepatócitos/fisiologia , Interações Hospedeiro-Patógeno , Receptor 2 Toll-Like/biossíntese , Regulação para Cima , Western Blotting , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Vírus da Hepatite B/patogenicidade , Humanos , Reação em Cadeia da Polimerase em Tempo Real
13.
Asian Pac J Cancer Prev ; 16(15): 6685-90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26434895

RESUMO

BACKGROUND: Genetic studies have shown a possible relationship between the rs16969968 polymorphism in CHRNA5 and the risk of lung cancer. However, the results have been conflicting. Thus we rigorously conducted a meta-analysis to clarify any association. MATERIALS AND METHODS: A total of 10 case-control studies involving 17,962 lung cancer cases and 77,216 control subjects were analysed. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to measure the strength of the association. RESULTS: We found the CHRNA5 rs16969968 polymorphism to be associated with the risk of lung cancer (AA vs GG: OR=1.60, 95%CI=1.51-1.71). On stratified analysis by smoking status, a statistically significant increased risk was observed in the smoking group (AA vs GG: OR=1.80, 95%CI=1.61-2.01). However, this polymorphism was not associated with lung cancer risk in Asians (AA vs GG: OR=0.95, 95%CI=0.35-2.59), whereas it was linked to increased risk of lung cancer among Caucasians (AA vs GG: OR=1.65, 95%CI=1.55-1.76). CONCLUSIONS: Our meta-analysis provided statistical evidence for a strong association between rs16969968 polymorphism and the risk of lung cancer, especially in smokers and Caucasians. Application of this relationship may contribute to identification of individuals at high risk of lung cancer and indicate a chemoprevention target.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Grupo com Ancestrais do Continente Europeu/genética , Neoplasias Pulmonares/genética , Proteínas do Tecido Nervoso/genética , Receptores Nicotínicos/genética , Estudos de Casos e Controles , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Fumar
14.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 43(3): 293-7, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-24998652

RESUMO

OBJECTIVE: To investigate the effects of simvastatin on atherosclerosis and central aortic pressure in ApoE-knockout (ApoE-/-) mice. METHODS: Ten 5-week-old male ApoE-/- mice and 5 C57 mice were fed with high-lipid diet for 3 weeks, and then C57 mice (WT group) and 5 ApoE-/- mice (ApoE-/- group) were given 1% carboxymethyl cellulose solution (8 ml·kg-1·d-1), and another 5 ApoE-/- mice (ApoE-/-/S group) were given simvastatin solution (50 mg·kg-1·d-1) by gavege for 3 weeks. The areas of atherosclerotic lesion in aortic root, central aortic pressure and serum lipid levels were examined. RESULTS: No atherosclerotic plaques were observed in WT group. Compared with ApoE-/- group, simvastatin significantly decreased atherosclerotic lesion area in aortic root (89 818.05±16 980.93 µm2 vs 34 937.01±13 280.65 µm2, P<0.05). The systolic pressure (SP), mean arterial pressure (MAP), pulse pressure (PP) and diastolic pressure (DP) of central aortic pressure were significantly increased in ApoE-/- group compared with those in WT group (P<0.05). Compared to ApoE-/- group, the SP, MAP and PP of central aortic pressure were significantly reduced in ApoE-/-/S group (P<0.05). SP and MAP of central aortic pressure were positively correlated with atherosclerotic lesion area (SP: r=0.7152, P=0.0461; PP: r=0.7594, P=0.0288). Compared with WT group, serum triglyceride, total cholesterol and low-density lipoprotein levels were markedly increased in ApoE-/- group (P<0.05). Serum high-density lipoprotein level was decreased in ApoE-/- group compared with WT group. No differences in serum triglyceride, total cholesterol, low-density lipoprotein and high-density lipoprotein levels were found between ApoE-/- group and ApoE-/-/S group. CONCLUSION: Simvastatin can attenuate atherosclerosis of aorta in ApoE-/- mice, which is associated with the reduced central aortic systolic pressure but not with the serum lipids levels.


Assuntos
Apolipoproteínas E/genética , Pressão Arterial/efeitos dos fármacos , Aterosclerose/tratamento farmacológico , Sinvastatina/farmacologia , Animais , Aterosclerose/genética , Aterosclerose/fisiopatologia , Colesterol/sangue , Modelos Animais de Doenças , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Camundongos , Camundongos Knockout , Triglicerídeos/sangue
15.
Mol Biol Rep ; 41(7): 4253-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24584519

RESUMO

Acute respiratory distress syndrome (ARDS) is a contemporary term incorporating the historic 'acute lung injury' and the colloquial term 'shock lung'. ARDS remains a serious and enigmatic human disease, causing significant mortality. The mechanisms involved at the alveolar cell/capillary endothelial interface have been explored but to date we lack clarity on the role of intracellular calcium ([Ca(2+)]i) fluxes across this interface. To explore the mechanisms of Ca(2+) induced inflammatory reaction in epithelial cells and pulmonary microvascular endothelial cells (HMVEC) located at the two sides of blood-air barrier, lung epithelial A549 and HMVEC cells were treated with LPS. Our results demonstrated that LPS evoked the increase of [Ca(2+)]i, TNF-α and IL-8 in both cells types. The [Ca(2+)]i increases involved intracellular but not extracellular Ca(2+) sources in A549, but both intracellular and extracellular Ca(2+) sources in HMVEC cells. The effects of LPS on both cells types were completely inhibited by the combination of LPS and CaSR-targeted siRNA. Furthermore, LPS-inhibited cell proliferations were significantly reversed by the combined treatment. Therefore, LPS induced different mechanisms of [Ca(2+)]i increase during the activation of CaSR in A549 and HMVEC cells, which translates into functional outputs related to ARDS.


Assuntos
Cálcio/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Células Epiteliais/metabolismo , Lipopolissacarídeos/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Expressão Gênica , Humanos , Interleucina-8/biossíntese , Interleucina-8/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Modelos Biológicos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores de Detecção de Cálcio/antagonistas & inibidores , Receptores de Detecção de Cálcio/genética , Receptores de Detecção de Cálcio/metabolismo , /metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/metabolismo
16.
J Sci Food Agric ; 94(13): 2794-800, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24585458

RESUMO

BACKGROUND: Arabinoxylans (AXs) are partially water-extractable polymers that cause problems of viscosity and filterability during beer brewing. This study investigated the effects of Kolbach index (KI) on water-extractable AXs (WEAXs). RESULTS: KI had positive correlations with extract (r = 0.845) and free amino nitrogen (FAN) (r = 0.958). The contents of malt WEAXs (WEAXsm), total AXs and wort AXs (WAXs) were 10.8-11.6 g kg⁻¹, 57.5-60.8 g kg⁻¹ and 137.5-140.5 mg per 100 mL respectively and the corresponding arabinose/xylose (A/X) ratios were 0.52-0.56, 0.55-0.62 and 0.48-0.50. The molecular weight (Mw) ranged from 4.92 × 104 to 6.93 × 104 Da for WEAXsm and from 1.24 × 104 to 2.90 × 104 Da for WAXs. KI had negative correlations with the average degree of polymerization (avDP) of malt (r = -0.877) and wort (r = -0.978). Wort viscosity showed a positive correlation with the Mw of WEAXsm (Mwm) (r = 0.821). CONCLUSION: Increasing KI can promote the degradation of the xylan backbone, while it cannot affect the branching of the polymer chain and the content and Mw of WEAXs.


Assuntos
Manipulação de Alimentos , Qualidade dos Alimentos , Germinação , Sementes/química , Triticum/química , Xilanos/análise , Algoritmos , Arabinose/análise , Proteínas de Bactérias/metabolismo , Fenômenos Químicos , China , Glicosídeo Hidrolases/metabolismo , Hidrólise , Fenômenos Mecânicos , Peso Molecular , Polimerização , Sementes/crescimento & desenvolvimento , Solubilidade , Triticum/crescimento & desenvolvimento , Viscosidade , Xilanos/química , Xilanos/metabolismo , Xilose/análise , alfa-Amilases/metabolismo
17.
Int J Infect Dis ; 16(7): e558-64, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22609014

RESUMO

OBJECTIVES: Sepsis is a leading cause of death in critically ill patients, and apoptosis plays a major role in the pathophysiology of sepsis. Elevated levels of circulating nucleosomes released by apoptotic cells have been detected in patients with severe sepsis and septic shock. The aim of this study was to evaluate the diagnostic/prognostic value of circulating nucleosomes in sepsis. METHODS: Seventy-four newly admitted patients with an estimated length of stay in the intensive care unit of more than 48 h, were prospectively enrolled as cohort 1. The second independent cohort (cohort 2) consisted of 91 post-surgery patients. Patients receiving chemotherapy, those with AIDS, those on steroid treatment, and those undergoing transplants were excluded. Levels of circulating nucleosomes within 24h of admission in both cohorts, and for cohort 1 also on days 3, 5, and 7 and a last time-point of ICU discharge or at imminent death, were measured and analyzed for their capacity to predict sepsis. The severity of the inflammatory response and organ dysfunction were assessed by cytokine levels and sepsis scores. RESULTS: Nucleosome levels on admission in septic patients were significantly higher than those in non-septic controls in both of the cohorts. The area under the receiver operating characteristic curve for admission nucleosome levels to differentiate septic patients from non-septic patients was 0.70 (95% confidence interval (CI) 0.51-0.88) in cohort 1, 0.66 (95% CI 0.55-0.79) in cohort 2, and 0.67 (95% CI 0.55-0.79) in all of the subjects. After multiple logistic regression analysis, circulating nucleosomes remained as an independent predictor of sepsis. Furthermore, the levels of circulating nucleosomes on admission were significantly correlated with the inflammatory response and organ dysfunction in sepsis. Meanwhile, a trend was observed for admission levels of circulating nucleosomes in non-survivors to be higher than those in survivors. CONCLUSIONS: The level of circulating nucleosomes in the serum has a predictive value for sepsis and organ dysfunction and may serve as a candidate biomarker for the diagnosis/prognosis of sepsis. Further studies are warranted to confirm the present findings.


Assuntos
Biomarcadores/sangue , Estado Terminal , Insuficiência de Múltiplos Órgãos/diagnóstico , Nucleossomos/metabolismo , Sepse/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/sangue , Valor Preditivo dos Testes , Prognóstico , Sepse/sangue , Síndrome de Resposta Inflamatória Sistêmica , Adulto Jovem
18.
Mol Cell Biochem ; 347(1-2): 175-82, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20953987

RESUMO

Thioredoxin interacting protein (Txnip) is one of the most abundantly up-regulated genes in response to hyperglycemia. The increased renal expression of Txnip was associated with type IV collagen accumulation in streptozotocin-induced diabetic mice. As the mechanism of action of high glucose is unknown, we undertook the investigation of the signaling pathway on the upregulation of Txnip expression induced by high glucose in rat mesangial cells. Rat mesangial cells were exposed to normal (5.5 mM) or high (25 mM) glucose at different time points. Txnip expression was determined using real-time RT-PCR and western-blotting at transcription and translation level, respectively. Intracellular reactive oxygen species (ROS) was detected by FACS Calibur flow cytometer using fluorescent probe (DCFH-DA).The treatment with high glucose resulted in an increase of Txnip mRNA from 4 h to 12 h and Txnip protein from 12 to 24 h in comparison with normal glucose condition. In addition, N-acetyl-cysteine (NAC) was found to decrease Txnip protein expression under high glucose condition. Furthermore, p38MAPK inhibitor SB203580 suppressed Txnip expression at transcription and protein level significantly to high glucose exposure. These results suggest that high glucose exposure improves Txnip mRNA and protein expression level by ROS/MEK/MAPK signaling pathway.


Assuntos
Proteínas de Transporte/genética , Glucose/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células Mesangiais/enzimologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos dos fármacos , Acetilcisteína/farmacologia , Animais , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células Mesangiais/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Fatores de Tempo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
19.
J Exp Clin Cancer Res ; 29: 89, 2010 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-20598162

RESUMO

BACKGROUND: ECRG4 has been shown to be a candidate tumor suppressor in several tumors, but its role in glioma remains poorly understood. In this study, we examined the mRNA expression of ECRG4 and investigated its biological role in glioma cells. METHODS: Real-time PCR was used to examine expression of ECRG4 in gliomas and their matched brain tissues. The effect of ECRG4 expression on cell proliferation, invasion, and migration was investigated in human U251 glioma cells. Finally, the regulation of transcription factor NF-kB by ECRG4 was evaluated by western blotting. RESULTS: Of the 10 paired samples analyzed, 9 glioma tissues displayed the decreased expression of ECRG4 compared to matched normal brain tissues. Cells transfected with ECRG4 showed significantly decreased cell proliferation as evaluated by MTT and colony formation assays. Furthermore, overexpression inhibited cell migration and invasion in transwell and Boyden chamber experiments and retarded the cell cycle progression from G1 to S phase by FACSCaliber cytometry. Protein levels of nuclear transcription factor NF-kB, which is involved in cell proliferation, inversely correlated with ECRG4 expression. CONCLUSION: Our data suggest that ECRG4 serves as a tumor suppressor in glioma.


Assuntos
Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/prevenção & controle , Proliferação de Células , Glioma/patologia , Glioma/prevenção & controle , Proteínas de Neoplasias/metabolismo , Western Blotting , Neoplasias Encefálicas/metabolismo , Estudos de Casos e Controles , Adesão Celular , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , Humanos , Técnicas Imunoenzimáticas , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor
20.
Regul Pept ; 154(1-3): 69-76, 2009 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-19154760

RESUMO

Increased mesangial cell proliferation is one of the major pathologic features in the early stage of diabetic nephropathy (DN). Carnosine is an endogenously synthesized dipeptide that has been reported as a protective factor in diabetic nephropathy. However, the underlying mechanism involved in this effect remains to be elucidated. In this study, the effect of carnosine on cell proliferation and its underlying mechanisms were investigated in cultured rat mesangial cells by the methylthiazoletetrazolium (MTT) assay, the 5-bromo-2-deoxy-uridine (BrdU) cell proliferation assay, flow cytometry and western blotting. The results showed that pretreatment of mesangial cells with carnosine significantly inhibited cell proliferation and DNA synthesis in a dose-dependent manner by increasing the cell population in G1 and reducing that in S-phase. In addition, carnosine could reverse high glucose-induced down-regulation of cyclin-dependent kinase inhibitor p21 but not that of p27. Furthermore, carnosine could reduce the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and p38 mitogen-activated protein kinase (p38 MAPK). Taken together, these results suggest that carnosine can inhibit mesangial cell proliferation by modulating cell cycle progress, indicating that carnosine could be a potential therapeutic agent for the prevention of DN in the early stage.


Assuntos
Carnosina/farmacologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glucose/farmacologia , Células Mesangiais/metabolismo , Animais , Bromodesoxiuridina/metabolismo , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Formazans/metabolismo , L-Lactato Desidrogenase/metabolismo , Ratos , Sais de Tetrazólio/metabolismo , Fatores de Tempo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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