RESUMO
The question of whether all materials can solidify into the glassy form proposed by Turnbull half a century ago remains unsolved. Some of the simplest systems of monatomic metals have not been vitrified, especially the close-packed face-centred cubic metals. Here we report the vitrification of gold, which is notoriously difficult to be vitrified, and several similar close-packed face-centred cubic and hexagonal metals using a method of picosecond pulsed laser ablation in a liquid medium. The vitrification occurs through the rapid cooling during laser ablation and the inhibition of nucleation by the liquid medium. Using this method, a large number of atomic configurations, including glassy configurations, can be generated simultaneously, from which a stable glass state can be sampled. Simulations demonstrate that the favourable stability of monatomic metals stems from the strong topological frustration of icosahedra-like clusters. Our work breaks the limitation of the glass-forming ability of matter, indicating that vitrification is an intrinsic property of matter and providing a strategy for the preparation and design of metallic glasses from an atomic configuration perspective.
RESUMO
Gut microbiota alterations manifest as intermittent hypoxia and fragmented sleep, thereby mimicking obstructive sleep apnea-hypopnea syndrome (OSAHS). Here, we sought to perform the first direct survey of gut microbial dysbiosis over a range of apnea-hypopnea indices (AHI) among patients with OSAHS. We obtained fecal samples from 93 patients with OSAHS [5 < AHI ≤ 15 (n=40), 15 < AHI ≤ 30 (n=23), and AHI ≥ 30 (n=30)] and 20 controls (AHI ≤ 5) and determined the microbiome composition via 16S rRNA pyrosequencing and bioinformatics analysis of variable regions 3-4. We measured fasting levels of homocysteine (HCY), interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α). Results revealed gut microbial dysbiosis in several patients with varying severities of OSAHS, reliably separating them from controls with a receiver operating characteristic-area under the curve (ROC-AUC) of 0.789. Functional analysis in the microbiomes of patients revealed alterations; additionally, decreased in short-chain fatty acid (SCFA)-producing bacteria and increased pathogens, accompanied by elevated levels of IL-6. Lactobacillus levels correlated with HCY levels. Stratification analysis revealed that the Ruminococcus enterotype posed the highest risk for patients with OSAHS. Our results show that the presence of an altered microbiome is associated with HCY among OSAHS patients. These changes in the levels of SCFA affect the levels of pathogens that play a pathophysiological role in OSAHS and related metabolic comorbidities.
Assuntos
Bactérias/isolamento & purificação , Microbioma Gastrointestinal , Intestinos/microbiologia , Doenças Metabólicas/microbiologia , Apneia Obstrutiva do Sono/microbiologia , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Comorbidade , Disbiose , Fezes/microbiologia , Feminino , Homocisteína/sangue , Interações Hospedeiro-Patógeno , Humanos , Masculino , Doenças Metabólicas/sangue , Doenças Metabólicas/diagnóstico , Doenças Metabólicas/epidemiologia , Pessoa de Meia-Idade , Apneia Obstrutiva do Sono/sangue , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologiaRESUMO
Currently available data regarding the blood levels of erythropoietin (EPO) in sleep apnea (SA) patients are contradictory. The aim of the present meta-analysis was to evaluate the EPO levels in SA patients via quantitative analysis. A systematic search of Pubmed, Embase, and Web of Science were performed. EPO levels in SA group and control group were extracted from each eligible study. Weight mean difference (WMD) or Standard mean difference (SMD) with 95% confidence interval (CI) was calculated by using fixed-effects or random effect model analysis according to the degree of heterogeneity between studies. A total of 9 studies involving 407 participants were enrolled. The results indicated that EPO levels in SA group were significantly higher than that in control group (SMD 0.61, 95% CI 0.11-1.11, p = 0.016). Significantly higher EPO levels were found in patients with body mass index <30 kg/m2, and cardiovascular complications in the subsequent subgroup analysis (both p < 0.05). High blood EPO levels were found in SA patients in the present meta-analysis.
Assuntos
Eritropoetina , Síndromes da Apneia do Sono/sangue , Eritropoetina/análise , Eritropoetina/sangue , Humanos , Estatística como AssuntoRESUMO
Angiotensin (Ang)-(1-7), a metabolite of AngI and AngII, is a counter-regulatory mediator of AngII. In the present study, we investigated the effects of Ang-(1-7) on AngII-induced apoptosis in human umbilical vein endothelial cells (HUVEC). To this end, HUVEC were pretreated with 10(-9), 10(-8), 10(-7) or 10(-6) mol/L Ang-(1-7) at for 30 min before being stimulated with 10(-6) mol/L Ang-II for another 24 h. Acridine orange/ethidium bromide and propidium iodide staining were used to analyse the effects of Ang-(1-7) on AngII-induced apoptosis. Alone, 10(-6) mol/L Ang-(1-7) had no effect on the apoptosis of HUVEC following exposure of cells for 30 min, whereas AngII (10(-6) mol/L, 24 h) significantly enhanced the number of apoptotic cells (P < 0.01). The AngII-induced apoptosis of HUVEC was suppressed by 10(-9)-10(-6) mol/L Ang-(1-7). The anti-apoptotic effects of Ang-(1-7) were almost completely abolished by A-779 (10(-6) mol/L, 30 min), a specific Mas receptor antagonist. In addition, Ang-(1-7) inhibited AngII-induced accumulation of cleaved caspase 3 and enhanced the expression of the anti-apoptotic factor Bcl-2 at both the mRNA and protein levels. Angiotensin II upregulated the expression of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), which is involved in endothelial apoptosis, at both the mRNA and protein levels. This effect was blocked by Ang-(1-7) in a concentration-dependent manner, although A-779 almost completely reversed Ang-(1-7)-mediated inhibition of AngII-induced upregulation of LOX-1. Silencing of LOX-1 using short interference RNA enhanced the protective effects of Ang-(1-7) against AngII-induced apoptosis in HUVEC. Together, the results suggest that Ang-(1-7) ameliorates AngII-induced apoptosis of HUVEC at least in part by suppressing LOX-1 expression.
Assuntos
Angiotensina II/farmacologia , Angiotensina I/farmacologia , Apoptose/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Receptores Depuradores Classe E/metabolismo , Western Blotting , Caspase 3/metabolismo , Técnicas de Cultura de Células , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Citometria de Fluxo , Células Endoteliais da Veia Umbilical Humana , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptores Depuradores Classe E/genética , Regulação para CimaRESUMO
OBJECTIVE: Genistein could inhibit the development of atherosclerosis. This study explored the role of PI3K/AKT signaling during genistein promoted eNOS activation. METHODS: Human umbilical vein endothelial cells (HUVECs) were incubated with ox-LDL (100 mg/L), then treated with genistein (100 nmol/L) for 5, 10, 15, 30 and 60 min. The production of NO was assessed by Griess reaction in cell culture supernatant. The mRNA expression of endothelial nitric oxide synthase (eNOS) was detected by reverse transcription-polymerase chain reaction (RT-PCR). The protein expression of eNOS and phosphorylation eNOS(Ser(1179)) were determined by Western blot. The effect of genistein on phosphorylation eNOS(Ser(1179)) level was also observed in the presence of LY294002 or NSC154020 (PI3K and AKT inhibitors). RESULTS: The concentration of NO and the expression level of phosphorylation eNOS(Ser(1179)) were significantly increased in ox-LDL + genistein treated cells than ox-LDL treated cells (all P < 0.05), and the peak effects were observed at 15 min, however, eNOS mRNA and non-phosphorylated eNOS protein expression were similar between the two groups (P > 0.05). Furthermore, the expression level of phosphorylation eNOS(Ser(1179)) was significantly lower in PIK3/AKT inhibitors LY294002 and NSC154020 treated cells compared with ox-LDL + genistein treated cells (all P < 0.05). CONCLUSION: Genistein could promote the activity of eNOS through increasing phosphorylation eNOS(Ser(1179)) level through PI3K/AKT pathway.
Assuntos
Genisteína/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Fitoestrógenos/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
OBJECTIVE: To investigate the molecular pathway of substance P (SP) to induce osteoblastic differentiation. METHODS: Mesenchymal stem cells were isolated and cultured. The cultures were divided into four groups with Group A (control group) cultured without any factors, Group B cultured with SP, Group C cultured with SP and SP receptor neurokinin-1 (NK1) antagonist, and Group D cultured with SP NK1 antagonist respectively to induce osteoblastic cells differentiation. Osterix gene expression was detected by reverse transcription-polymerase chain reaction (RT-PCR) for three times after 1-2 weeks of cultivation and the results were analyzed by one-way analysis of variance (ANOVA). RESULTS: The log phase of bone marrow stromal cells appeared at 4-6 days. ALP staining revealed that the majority of cells, more than 95%, were positive and small blue-purple granules were found in the cytoplasm. And Group B, treated with SP, showed a higher level of ALP activity than the other three groups. Meanwhile, RT-PCR found that Osterix expression in Group B was obviously up-regulated, compared with other groups. But Osterix expression in Group D had no remarkable differences, compared with the controls. CONCLUSIONS: SP can up-regulate Osterix gene expression to stimulate differentiation of mesenchymal stem cells into osteoblastic cells at the final stage. The regulatory effect of SP on Osterix expression was dependant on SP NK1 receptors.
Assuntos
Osteoblastos/efeitos dos fármacos , Substância P/farmacologia , Fatores de Transcrição/genética , Fosfatase Alcalina/análise , Animais , Diferenciação Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Osteoblastos/citologia , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para CimaRESUMO
OBJECTIVE: to explore the clinical and microbiological characteristics of Rhizobium radiobacter infection, and therefore to provide information for the prevention and treatment of the disease. METHODS: the clinical and microbiological data were analyzed for patients proved to have Rhizobium radiobacter infection by blood culture obtained from May 2008 to July 2009 in the Second Affiliated Hospital of Fujian Medical University. Related literature were reviewed. RESULTS: there were 4 males and 2 females aging 5 - 88 years old. All the patients suffered from fever and chillsor malaise, and had increased peripheral WBC or neutrophil count. The majority (5/6) of the infections was pneumonia, characterized by mild cough and expectoration, lung rales, patchy infiltrates on chest X-ray. All the patients had underlying diseases or were immunocompromised. Five of the 6 patients had close soil exposure. Four of the 6 patients received broad-spectrum antibiotics or immunosuppressive therapy. Antibacterial susceptibility testing showed that, all the isolates of Rhizobium radiobacter were susceptible to the third generation cephalosporins, cephamycins, Carbapenems, fluoroquinolones, tetracycline, nitrofurantoin and some of the aminoglycosides, but resistant to penicillins, penicillins/enzyme inhibitors, first and fourth generation cephalosporins, and helices beta-lactamase antibiotics. There were no complications, and all patients recovered uneventfully after treatment with antibiotics according to the susceptibility testing. CONCLUSIONS: rhizobium radiobacter infections often occur in patients with underlying risk factors. The clinical manifestations of Rhizobium radiobacter infection are nonspecific. The organism is sensitive to most antibiotics, and the clinical outcome is favorable.
Assuntos
Agrobacterium tumefaciens , Pneumonia Bacteriana/microbiologia , Adulto , Idoso de 80 Anos ou mais , Agrobacterium tumefaciens/efeitos dos fármacos , Antibacterianos/uso terapêutico , Pré-Escolar , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/tratamento farmacológico , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Adulto JovemRESUMO
OBJECTIVE: To summarize the clinical characteristics and therapeutic experience of A/H5N1 infected patient with intractable bronchopleural fistula. METHOD: The data of a patient with A/H5N1 infection complicated with bronchopleural fistula was collected and analyzed. RESULTS: A 44-year-old woman with pneuminian was diagnosed as A/H5N1 infection by reverse-transcription polymerase chain reaction (RT-PCR) in laboratory from the sample of secretion of respiratory tracts. She had exposed to sick or dead poultry 3 days before development of illness. She developed acute respiratory distress syndrome 7 days after onset of sickness. After comprehensive management with antiviral agents, antibiotics, convalescent serum and invasive ventilation, her clinical condition improved and turned to stable. However, 16 days after onset of illness, her clinical situation deteriorated due to ventilator-associated pneumonia, bilateral pneumothorax and persistent right bronchopleural fistula. After partly failure of beside assist thoracoscopy to fix the pleural fistula, transbronchoscopic bronchial occlusion by autoblood was explored and the air leakage stopped soon after occlusion. Three days after the autoblood clot was expectorated out and air leak recurred. Then, bronchopleural fistula on the surface of visceral pleura was successfully blocked by biogel and OB gel through pleural cavity by fibrobronchoscopy. The patient was discharged from the hospital 99 days after onset of illness (at the 94th hospital day). CONCLUSION: Bronchopleural fistula was an intractable complication for patient with A/H5N1 infection. Occlusion operation by biogel and OB gel through bronchoscopy might be an alternative choice for fixing the bronchopleural fistula.
Assuntos
Fístula Brônquica/terapia , Influenza Humana/terapia , Doenças Pleurais/terapia , Adulto , Fístula Brônquica/complicações , Fístula Brônquica/virologia , China , Feminino , Humanos , Virus da Influenza A Subtipo H5N1 , Influenza Humana/complicações , Influenza Humana/virologia , Doenças Pleurais/complicações , Doenças Pleurais/virologia , Resultado do TratamentoRESUMO
OBJECTIVE: To evaluate the effect, complications and safety of transbronchoscopic balloon detection (TBD) and selective bronchus occlusion (SBO) for intractable pneumothorax. METHODS: Forty cases of pneumothorax from 5 teaching hospitals in Fujian province were included for this study. TBD was performed in all the 40 cases for whom chest tube drainage had lasted for more than 7days but failed to close the pleura fistulae. Bronchi leading to pleura fistulae (the target bronchus) were detected by balloon-catheter (Olympus B7-2C) through bronchoscope. After the target bronchus was located, SBO procedures were performed. Autologous blood (20 ml to 30 ml) was injected into the target bronchus and followed by thrombin solution (1000 U) through balloon-catheter. In 10 cases, oxygenation and pulse rate were recorded by pulse-oximeter (Healthdyne 920M) during TBD and SBO. Another 10 cases undergoing bronchoscope without performing TBD and SBO served as the controls. Thorax CT, white blood cell count, neutrophil count and body temperature were measured after SBO. RESULTS: Bronchi leading to pleura fistulae were located by TBD in 34 out of the 40 cases. Air leakage was stopped after the first occlusion in 30 cases, but 5 of which underwent a second occlusion because of recurrence in 72 h. Of the 5 cases, air leakage was stopped in 3, and surgery was required in 2. Taken together, 28 of the 34 cases were cured by SBO and 6 failed. There were no statistically differences between the treatment group and the control group in oxygenation changes during TBD and SBO procedures. In 10 cases thorax CT scan was followed up in 7 days after SBO, and no obstructive atelectasis was found. In 20 cases peripheral white blood cell count was followed up 72 hours after SBO. Leukocytosis (> 10.0 x 10(9)/L) was found in 3, in which pulmonary infection was diagnosed, and leukocytosis was present in 2 cases before the procedure. Five patients (5/34) experienced mild to moderate fever, which resolved quickly. CONCLUSION: TBD/SBO are safe and effective procedures for intractable pneumothorax.
Assuntos
Oclusão com Balão/métodos , Pneumotórax/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Broncoscopia , Tubos Torácicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto JovemRESUMO
Obstructive sleep apnea-hypopnea syndrome (OSAHS) is an independent risk factor for hypertension (HTN). The oral microbiota plays a pathophysiological role in cardiovascular diseases; however, there are few reports directly investigating and identifying the organisms involved in OSAHS-related HTN. Therefore, this study aimed to identify those organisms. We obtained 139 oral samples and determined the microbiome composition using pyrosequencing and bioinformatic analyses of the 16S rRNA. We examined the fasting levels of cytokines and homocysteine in all participants and analyzed the correlations between the oral microbiota and homocysteine levels. We determined the molecular mechanism underlying HTN by investigating the genetic composition of the strains in the blood. We detected higher relative abundances of Porphyromonas and Aggregatibacter and elevated proinflammatory cytokines in patients with OSAHS of varying severity compared with individuals without OSAHS; however, the two organisms were not measured in the blood samples from all participants. High levels of specific Porphyromonas bacteria were detected in patients with OSAHS with and without HTN, whereas the relative abundance of Aggregatibacter was negatively correlated with the homocysteine level. The receiver operating characteristic curve analysis of controls and patients with OSAHS resulted in area under the curve values of 0.759 and 0.641 for patients with OSAHS with or without HTN, respectively. We found that the predictive function of oral microbiota was different in patients with OSAHS with and without HTN. However, there was no direct invasion by the two organisms causing endothelial cell injury, leading to speculation regarding the other mechanisms that may lead to HTN. Elucidating the differences in the oral microbiome will help us understand the pathogenesis of OSAHS-related HTN.
Assuntos
Aggregatibacter/isolamento & purificação , Hipertensão/microbiologia , Microbiota , Porphyromonas/isolamento & purificação , Apneia Obstrutiva do Sono/complicações , Adulto , Estudos de Casos e Controles , Citocinas/sangue , Feminino , Homocisteína/sangue , Humanos , Hipertensão/sangue , Masculino , Pessoa de Meia-Idade , Boca/microbiologia , Apneia Obstrutiva do Sono/sangueRESUMO
INTRODUCTION: Intermittent hypoxia and sleep fragmentation are critical pathophysiological processes involved in obstructive sleep apnea-hypopnea syndrome (OSAHS). Those manifestations independently affect similar brain regions and contribute to OSAHS-related comorbidities that are known to be related to the host gut alteration microbiota. We hypothesized that gut microbiota disruption may cross talk the brain function via the microbiota-gut-brain axis. Thus, we aim to survey enterotypes and polysomnographic data of patients with OSAHS. METHODS: Subjects were diagnosed by polysomnography, from whom fecal samples were obtained and analyzed for the microbiome composition by variable regions 3-4 of 16S rRNA pyrosequencing and bioinformatic analyses. We examined the fasting levels of interleukin-6 and tumor necrosis factor-alpha of all subjects. RESULTS: Three enterotypes Bacteroides, Ruminococcus, and Prevotella were identified in patients with OSAHS. Arousal-related parameters or sleep stages are significantly disrupted in apnea-hypopnea index (AHI) ≥15 patients with Prevotella enterotype; further analysis this enterotype subjects, obstructive, central, and mixed apnea indices, and mean heart rate are also significantly elevated in AHI ≥15 patients. However, blood cytokines levels of all subjects were not significantly different. CONCLUSIONS: This study indicates the possibility of pathophysiological interplay between enterotypes and sleeps structure disruption in sleep apnea through a microbiota-gut-brain axis and offers some new insight toward the pathogenesis of OSAHS.
Assuntos
Microbioma Gastrointestinal/fisiologia , Hipóxia , Prevotella , Apneia Obstrutiva do Sono , Sono/fisiologia , Adulto , Correlação de Dados , Feminino , Genes Microbianos , Humanos , Hipóxia/etiologia , Hipóxia/fisiopatologia , Hipóxia/psicologia , Masculino , Pessoa de Meia-Idade , Polissonografia/métodos , Prevotella/isolamento & purificação , Prevotella/fisiologia , RNA Ribossômico 16S/isolamento & purificação , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/microbiologia , Apneia Obstrutiva do Sono/psicologiaRESUMO
OBJECTIVE: To investigate the apoptosis-inhancing effect of the combination of arsenic trioxide (As2O3 ) and buthionine sulfoximine (BSO) on multidrug-resistant human leukemic K562/ADM cells, to compare the effect of As2O3 alone and As2O3 combined with BSO and As2O3 alone, and to determine the effect of intracellular GSH content on this treatment. METHODS: As2O3 was used in a dose of 0.5 micromol/L, 2.0 micromol/L and 5.0 micromol/L, respectively, and BSO was used in a dose of 100 micromol/L in the culture of multidrug-resistant human leukenic K562/ADM cells. The cell proliferation activity was assessed with MTT assay. The cell apoptosis was detected by flow cytometry using Annexin-V and propidium iodide (PI) staining. Intracellular GSH content was measured using glutathione assay kit by spectrophotometry. RESULTS: After the GSH contents were reduced by the combination of arsenic in clinic dose (0.5, 2 micromol/L) and BSO (100 micromol/L), respectively, the K562/ADM cell proliferation activity was obviously inhibited and the cell apoptosis-inducing effect was advanced in 24 hours. In 48 and 72 hours, the effect of the combination group (clinic dose arsenic group) was significantly stronger than that of clinic dose arsenic alone group and the high dose arsenic alone group. CONCLUSION: The cell apoptosis-inducing effect of arsenic in combination of BSO on multidrug resistant human leukemia K562/ADM cells is significantly enhanced in comparison with that of arsenic alone. The reduction of intracellular glutathione content is closely correlated with this apoptosis-enhancing effect.
Assuntos
Apoptose/efeitos dos fármacos , Arsenicais/farmacologia , Butionina Sulfoximina/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Glutationa/metabolismo , Óxidos/farmacologia , Antimetabólitos Antineoplásicos/farmacologia , Antineoplásicos/farmacologia , Trióxido de Arsênio , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Humanos , Células K562RESUMO
Endothelial nitric oxidase synthase (eNOS) uncoupling plays a causal role in endothelial dysfunction in atherosclerosis. Genistein consumption has been associated with the prevention of atherosclerosis. However, the effect of genistein on eNOS uncoupling has not been reported. A model of oxidized low-density lipoprotein (ox-LDL)-induced injury on human umbilical vein endothelial cells (HUVECs) was established to evaluate the effect of genistein on eNOS uncoupling. We investigated the effect of genistein on NADPH oxidase-dependent superoxide production, NOX4 expression, BH4 synthesis and oxidation, the expression of GTP cyclohydrolase 1 (GCH1) and dihydrofolate reductase (DHFR). The results showed that genistein decreased superoxide production and NOX4 expression, enhanced the ratio of BH4/BH2, augmented the expressions of GCH1 and DHFR. Accompanied with genistein ameliorating eNOS uncoupling, genistein elevated the expression of sirtuin-1; furthermore, the effects of genistein on eNOS uncoupling were blunted with sirtuin-1 siRNA. The present study indicated that genistein ameliorated eNOS uncoupling was concerned with sirtuin-1 pathway in ox-LDL-injured HUVECs.
Assuntos
Genisteína/farmacologia , Lipoproteínas LDL/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Sirtuína 1/metabolismo , GTP Cicloidrolase/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Óxido Nítrico Sintase Tipo III/metabolismo , Superóxidos/metabolismoRESUMO
AIM: To prospectively study neurocognitive performance following carotid endarterectomy (CEA) in various follow-up periods, taking into account the potential confounding factors. MATERIAL AND METHODS: Thirty-six patients with carotid artery stenosis received CEA (group A). Thirty-one patients underwent surgery for femoropopliteal occlusive disease served as controls (group B). Neuropsychological testing and brain magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) was repeated preoperatively, within 3 days and at 3 months after surgery. RESULTS: No patient had DWI evidence of procedure-related cerebral ischemia. Preoperative baseline scores of groups A and B were not statistically different in mini mental state examination (MMSE) or clock drawing task (CDT) score. MMSE and CDT scores were significantly reduced for patients in group A (p < 0.01) within 3 days after CEA. Differences of MMSE score (p=0.48) and CDT score (p=0.26) between baseline and 3 months after surgery in group A were not statistically significant. No statistically significant change of MMSE score and CDT score in group B was observed at 3 days and 3 months after the surgery. Degree of internal carotid artery (ICA) stenosis (p=0.029) and duration of ICA clamping (p=0.031) were significantly higher in patients with cognitive impairment immediately after CEA than in those without that. CONCLUSION: Our study demonstrated cognitive decline for the patients with unilateral carotid stenosis at early stage after CEA and a restorative effect at 3 months after CEA. Postoperative early cognitive impairment might be associated with intraoperative temporary hypoperfusion and postoperative hyperperfusion, not the microembolic event.
Assuntos
Estenose das Carótidas/cirurgia , Disfunção Cognitiva/diagnóstico , Endarterectomia das Carótidas/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Complicações Pós-Operatórias/diagnóstico , Idoso , Disfunção Cognitiva/etiologia , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologiaRESUMO
In this study, a series of injectable thermoreversible and thermogelling PDLLA-PEG-PDLLA copolymers were developed and a systematic evaluation of the thermogelling system both in vitro and in vivo was performed. The aqueous PDLLA-PEG-PDLLA solutions above a critical gel concentration could transform into hydrogel spontaneously within 2 minutes around the body temperature in vitro or in vivo. Modulating the molecular weight, block length and polymer concentration could adjust the sol-gel transition behavior and the mechanical properties of the hydrogels. The gelation was thermally reversible due to the physical interaction of copolymer micelles and no crystallization formed during the gelation. Little cytotoxicity and hemolysis of this polymer was found, and the inflammatory response after injecting the hydrogel to small-animal was acceptable. In vitro and in vivo degradation experiments illustrated that the physical hydrogel could retain its integrity as long as several weeks and eventually be degraded by hydrolysis. A rat model of sidewall defect-bowel abrasion was employed, and a significant reduction of post-operative adhesion has been found in the group of PDLLA-PEG-PDLLA hydrogel-treated, compared with untreated control group and commercial hyaluronic acid (HA) anti-adhesion hydrogel group. As such, this PDLLA-PEG-PDLLA hydrogel might be a promising candidate of injectable biomaterial for medical applications.
Assuntos
Hidrogéis/química , Hidrogéis/síntese química , Poliésteres/química , Poliésteres/síntese química , Polietilenoglicóis/química , Polietilenoglicóis/síntese química , Temperatura , Animais , Materiais Biocompatíveis/farmacologia , Modelos Animais de Doenças , Feminino , Injeções Subcutâneas , Camundongos Endogâmicos BALB C , Micelas , Peritônio/efeitos dos fármacos , Peritônio/patologia , Transição de Fase , Ratos Sprague-Dawley , Reologia , Aderências Teciduais/prevenção & controleRESUMO
The aim of the present study was to explore the expression of POLD4 in human lung adenocarcinoma A549 cells under 4-nitroquinoline-1-oxide (4NQO) stimulation to investigate the role of POLD4 in smoking-induced lung cancer. The lung cancer A549 cell line was treated with 4NQO, with or without MG132 (an inhibitor of proteasome activity), and subsequently the POLD4 level was determined by western blot analysis. Secondly, the cell sensitivity to 4NQO and Taxol was determined when the POLD4 expression level was downregulated by siRNA. The POLD4 protein levels in the A549 cells decreased following treatment with 4NQO; however, MG132 could reverse this phenotype. Downregulation of the POLD4 expression by siRNA enhanced A549 cell sensitivity to 4NQO, but not to Taxol. In conclusion, 4NQO affects human lung adenocarcinoma A549 cells by regulating the expression of POLD4.
RESUMO
Induction of oxidative stress has a causal role in atherosclerosis. The aim of the present study was to examine the role of lectinlike oxidized lowdensity lipoprotein receptor1 (LOX1) in oxidized lowdensity lipoprotein (OxLDL)induced oxidative stress in atherosclerosis. Small interfering RNA (siRNA) technology was employed to decrease the expression of LOX1 in mouse RAW264.7 macrophages and the effects of LOX1 silencing on OxLDLinduced reactive oxygen species (ROS) generation and NADPH oxidase (NOX) expression were investigated. The in vivo effects of reducing LOX1 were also examined in a mouse model (ApoE/) of highfat dietinduced atherosclerosis. Compared with the control cells, OxLDL exposure led to a significant (P<0.05) increase in the intracellular levels of malondialdehyde and ROS and a significant decrease in the activity of superoxide dismutase. Delivery of LOX1targeting siRNA significantly (P<0.05) reversed the alterations in oxidative stress parameters induced by OxLDL. LOX1 silencing downregulated the expression of NOX2, Rac1, p47phox and p22phox and impaired the activation of mitogenactivated protein kinases in OxLDLtreated cells. Adenoviral delivery of LOX1 siRNA caused a significant increase in the size of the fibrous cap and a decrease in the macrophage content in lesions, compared with the control mice. Western blot analysis demonstrated that the protein expression levels of NOX1, Rac1, p47phox and p22phox in aortic lesions were significantly lower in the LOX1 siRNA group than in the control group. LOX1 is implicated in OxLDLinduced oxidative stress of macrophages in atherosclerosis, which in part, involves the regulation of NADPH oxidases.
Assuntos
Aterosclerose/metabolismo , Aterosclerose/patologia , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Estresse Oxidativo , Receptores Depuradores Classe E/metabolismo , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/genética , Linhagem Celular , Grupo dos Citocromos b/genética , Grupo dos Citocromos b/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Inativação Gênica , Lipídeos/sangue , Lipoproteínas LDL/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , NADPH Oxidase 2 , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Placa Aterosclerótica/genética , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , RNA Interferente Pequeno/genética , Receptores Depuradores Classe E/genética , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismoRESUMO
Liquid-liquid transition, a phase transition of one liquid phase to another with the same composition, provides a key opportunity for investigating the relationship between liquid structures and dynamics. Here we report experimental evidences of a liquid-liquid transition in glass-forming La50Al35Ni15 melt above its liquidus temperature by (27)Al nuclear magnetic resonance including the temperature dependence of cage volume fluctuations and atomic diffusion. The observed dependence of the incubation time on the degree of undercooling is consistent with a first-order phase transition. Simulation results indicate that such transition is accompanied by the change of bond-orientational order without noticeable change in density. The temperature dependence of atomic diffusion revealed by simulations is also in agreement with experiments. These observations indicate the need of two-order parameters in describing phase transitions of liquids.
RESUMO
Three flavone glucosides, pleiosides A-C, were isolated from the leaves of Pleioblastus amarus, along with two known flavones: tricin and tricetin 3,5-dimethoxy-7-O-beta-d-glucopyranoside. Their structures were elucidated by extensive spectral studies. Pleiosides A-C were found to inhibit the proliferation of murine T and significantly stimulate the proliferation of murine B lymphocytes in vitro.
Assuntos
Adjuvantes Imunológicos/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Glucosídeos/química , Glucosídeos/farmacologia , Poaceae/química , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/isolamento & purificação , Animais , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Concanavalina A/farmacologia , Flavonoides/isolamento & purificação , Glucosídeos/isolamento & purificação , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Baço/citologia , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Timidina/análogos & derivados , Timidina/metabolismo , TrítioRESUMO
This study investigated the effects of testosterone and 17-beta-estradiol on tumor necrosis factor-alpha (TNF-alpha)-induced endothelial expression of E-selectin and vascular cell adhesion molecule-1 (VCAM-1) and the potential roles of hormone receptors involved in these actions. Human umbilical vein endothelial cells (HUVEC) were stimulated with TNF-alpha in the presence or absence of testosterone or 17-beta-estradiol, and the expression of E-selectin and VCAM-1 was investigated. As shown by Western blot analysis, co-administration with testosterone or 17-beta-estradiol increased the expression of E-selectin and VCAM-1 induced by TNF-alpha at 6 h and 3 h, respectively. Similarly, RT-PCR analysis revealed a significant increase in the amount of mRNA for E-selectin and VCAM-1 after co-administration with testosterone or 17-beta-estradiol in TNF-alpha-stimulated HUVEC. The presence of mRNA and proteins for androgen receptor and estrogen receptor alpha in HUVEC was verified by RT-PCR and Western blot. Flow cytometric analysis showed that preincubation with androgen receptor antagonist cyproterone and estrogen receptor antagonist tamoxifen completely abrogated the upregulating effects of testosterone and 17-beta-estradiol on TNF-alpha-induced E-selectin and VCAM-1 expression, respectively. Expression of TNF receptors in TNF-alpha-stimulated HUVEC was not influenced by testosterone and 17-beta-estradiol. The data indicate that both testosterone and 17-beta-estradiol increase TNF-alpha-induced E-selectin and VCAM-1 expression in endothelial cells via a receptor-mediated system, and expression of TNF receptors are not changed in these actions. The implications of these results for the facilitory effects of both sex hormones on immune reactions are discussed.