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701.
In vitro comparison of the photothermal anticancer activity of graphene nanoparticles and carbon nanotubes 总被引:1,自引:0,他引:1
Markovic ZM Harhaji-Trajkovic LM Todorovic-Markovic BM Kepić DP Arsikin KM Jovanović SP Pantovic AC Dramićanin MD Trajkovic VS 《Biomaterials》2011,32(4):1121-1129
The present study compared the photothermal anticancer activity of near-infrared (NIR)-excited graphene nanoparticles and carbon nanotubes (CNT). Despite lower NIR-absorbing capacity, suspension of polyvinylpyrrolidone-coated graphene sheets exposed to NIR radiation (808 nm, 2 W/cm(2)) generated more heat than DNA or sodium dodecylbenzenesulfonate-solubilized single-wall CNT under the same conditions. Accordingly, graphene nanoparticles performed significantly better than CNT in inducing photothermal death of U251 human glioma cells in vitro. The superior photothermal sensitivity of graphene sheets could be largely explained by their better dispersivity, which has been supported by a simple calculation taking into account thermodynamic, optical and geometrical properties of the two type of carbon nanoparticles. The mechanisms of graphene-mediated photothermal killing of cancer cells apparently involved oxidative stress and mitochondrial membrane depolarization resulting in mixed apoptotic and necrotic cell death characterized by caspase activation/DNA fragmentation and cell membrane damage, respectively. 相似文献
702.
Atanasovska-Stojanovska A Trajkov D Nares S Angelov N Spiroski M 《Human immunology》2011,72(5):446-450
Genetic polymorphisms in the interleukin-4 (IL4) gene have been reported to influence the host response to microbial challenge by altering levels of cytokine expression. We analyzed nucleotide polymorphisms in the promoter region of the IL4 gene and its relation with periodontal disease in a Macedonian population. The study population consisted of 92 unrelated subjects with chronic periodontitis and 286 healthy controls. DNA was isolated and IL4 genotyping performed by polymerase chain reaction-single-strand polymorphism (Heidelberg kit) for the alleles and genotypes of IL4 -1098, IL4 -590, and IL4 -33. Frequencies of IL4 haplotypes and the haplotype zygotes were also examined. Comparisons between groups were tested using the Pearson's p value. After Bonferroni adjustment, significant associations were detected between subjects with periodontitis and the following: (1) cytokine alleles IL4 -1098 and IL4 -33; (2) cytokine genotypes IL4 -1098/G:T; IL4 -1098/T:T, and IL4 -33/T:T, (3) cytokine haplotypes IL4/GCC, IL4/TCC, and IL4/TTC; and (4) cytokine haplotype zygotes IL4/TTC: TCC, IL4/TCT:TTT, and IL4/GCC:TTC. Cytokine polymorphism on the IL4 gene appears to be associated with susceptibility to chronic periodontitis in Macedonians. 相似文献
703.
704.
Kai Schommer Dejan Reljic Peter Bärtsch Peter Sauer 《Journal of negative results in biomedicine》2011,10(1):1-4
Background
Recently few studies tried to confirm the association between AF and lipoprotein(a) (Lp(a)), however the results remained conflicted. In present study we evaluated the possible interaction between Lp(a), inflammatory state and echocardiographic characteristics in patients after successful electrical cardioversion (EC) of persistent AF. We also tried to investigate the role of Lp(a) as a possible prognostic factor for AF recurrence after successful EC.Results
Data of 79 patients admitted due to planned EC was analyzed. After successful procedure patients were monitored for 2 years. For analytical purposes patients were divided in two groups according to AF recurrence. There was no significant difference between Lp(a) levels in both groups. We also didn't find any positive correlation between Lp(a) and CRP levels, as well as between Lp(a) levels and left atrium diameter. For logistic and survival analysis optimal cut-off value of Lp(a) ≥ 0.32 (upper quartile) was used. In logistic regression model with AF recurrence as dependent variable Lp(a) didn't show any statistically significant association with AF recurrence. Survival analysis showed slightly higher AF recurrence rate in group with higher Lp(a) levels but not to the level of statistical significance (log rank test, p = 0.62).Conclusions
We weren't able to confirm the association between Lp(a) levels and AF recurrence, inflammation and left atrium diameter in patients after successful EC of persistent AF. Further studies are needed to elucidate the role of Lp(a) in this clinical setting. 相似文献705.
BACKGROUND: Cardiovascular diseases are the leading cause of death in hemodialysis patients. Left ventricular (LV) hypertrophy is an important predictor of cardiovascular morbidity and mortality in these patients. Cardiac troponins (cTnT and cTnI) are indicators of myocardial cell damage. AIM: The aim of this study was to determine prevalence of LV hypertrophy, prevalence of elevated serum cTnT and cTnI in hemodialysis patients, and identify the correlation between cardiac troponins and LV hypertrophy. METHODS: The study included 115 hemodialysis patients (71 men and 44 women), mean age 53.30 +/- 12.17 years, mean time on dialysis 4.51 +/- 4.01 years and average Kt/Vsp 1.17 +/- 0.23. Mean serum cTnT was 0.14 +/- 0.23 ng/ml, mean serum troponin I 0.20 +/- 0.48 ng/ml. Mean LV posterior wall thickness in diastole (LVPWd) was 11.44 +/- 2.09 mm, mean LV interventricular septal wall thickness in diastole (IVSd) 11.21 +/- 2.12 mm, mean LV end diastolic volume index (iLVEDV) 100.80 +/- 34.62 mL/m2 and mean LV mass index (LVMi) 143.85 +/- 41.21 g/m2. RESULTS: We found statistically significant positive correlations (p <0.05) between serum troponin T concentration, IVSd, LVPWd and iLVEDV. A highly significant positive correlation (p < 0.01) was found between serum troponin T and LVMi. One-year follow-up showed that patients with cardiac troponin T > 0.10 ng/ml and cardiac troponin I > 0.15 ng/ml had significantly lower (p < 0.01) survival rate than patients with troponin T < or = 0.10 ng/ml and troponin I < or = 0.15 ng/ml. CONCLUSION: A significant positive correlation exists between serum troponin T concentration and echocardiographic indicators of LV hypertrophy in hemodialysis patients. Patients with higher serum levels of cardiac troponins have lower survival rates during one year follow up. 相似文献
706.
Pharmacologic suppression of oxidative damage and dendritic degeneration following kainic acid-induced excitotoxicity in mouse cerebrum 总被引:1,自引:0,他引:1
Intense seizure activity associated with status epilepticus and excitatory amino acid (EAA) imbalance initiates oxidative damage and neuronal injury in CA1 of the ventral hippocampus. We tested the hypothesis that dendritic degeneration of pyramidal neurons in the CA1 hippocampal area resulting from seizure-induced neurotoxicity is modulated by cerebral oxidative damage. Kainic acid (KA, 1 nmol/5 microl) was injected intracerebroventricularly to C57Bl/6 mice. F2-isoprostanes (F2-IsoPs) and F4-neuroprostanes (F4-NeuroPs) were used as surrogate measures of in vivo oxidative stress and biomarkers of lipid peroxidation. Nitric oxide synthase (NOS) activity was quantified by evaluating citrulline level and pyramidal neuron dendrites and spines were evaluated using rapid Golgi stains and a Neurolucida system. KA produced severe seizures in mice immediately after its administration and a significant (p<0.001) increase in F2-IsoPs, F4-NeuroPs and citrulline levels were seen 30 min following treatment. At the same time, hippocampal pyramidal neurons showed significant (p<0.001) reduction in dendritic length and spine density. In contrast, no significant change in neuronal dendrite and spine density or F2-IsoP, F4-NeuroPs and citrulline levels were found in mice pretreated with vitamin E (alpha-tocopherol, 100mg/kg, i.p.) for 3 days, or with N-tert-butyl-alpha-phenylnitrone (PBN, 200mg/kg, i.p.) or ibuprofen (inhibitors of cyclooxygenase, COX, 14 microg/ml of drinking water) for 2 weeks prior to KA treatment. These findings indicate novel interactions among free radical-induced generation of F2-IsoPs and F4-NeuroPs, nitric oxide and dendritic degeneration, closely associate oxidative damage to neuronal membranes with degeneration of the dendritic system, and point to possible interventions to limit severe damage in acute neurological disorders. 相似文献
707.
Terzić N Opsenica D Milić D Tinant B Smith KS Milhous WK Solaja BA 《Journal of medicinal chemistry》2007,50(21):5118-5127
The synthesis of deoxycholic acid (DCA)- and cholic acid (CA)-derived mixed tetraoxanes revealed that N-(2-dimethylamino)ethyl derivatives are potent antimalarials in vitro and in vivo. The tetraoxanes presented in this paper are dual inhibitors: besides curing mice in vivo without observed toxic effects, they kill cancer cell lines at very low concentrations. For example, DCA and CA derivatives 16 and 25 cured 3/5 (160 mg/kg/day) and 2/5 (40 mg/kg/day, MTD >960 mg/kg), respectively, and they were extremely active against melanoma LOX IMVI cancer, LC50 = 22 nM and 69 nM, respectively. 相似文献
708.
The main protective properties of two-component epoxy coating are connected by the formation of a barrier of a certain thickness between the material and aggressive, environmentally induced reactants. Anticorrosive pigment is added to the coating in order to improve its protective effects. The conditioning time refers to the time interval required for the achievement of satisfactory cohesion bonds between the coating components, as well as a satisfactory adhesion force between the coating and the base material surface. This paper presents insights obtained after experimental research into the influence of input variables (the content of anticorrosive pigment in the coating, dry-film thickness, and conditioning time) on corrosion resistance. The specimens were kept in the aggressive atmosphere of a salt-spray test chamber within time intervals of 120, 240 and 480 h, where they were cyclically sprayed with a 5% sodium chloride (NaCl) solution, and then examined in laboratory conditions. Such a procedure imitated the aggressive conditions of a service environment. After exposure in the salt-spray test chamber, the specimens were tested to determine the protective properties of the coating and to evaluate damage occurring on the coating, with the purpose of assessing the coating quality in relation to the stated input variables. At all times, when the test samples were exposed to the salt chamber atmosphere, the anti-corrosion pigment content was found to have the greatest influence with the thickness of the dry coating film. The conditioning time was an influential factor to a lesser extent, and only in some observed cases. By analyzing the interactions of the input variables and the results obtained based on mathematical models and reaction surfaces, it was possible to define the most optimal values of the input parameters. For example, after 480 h of exposure in a salt chamber, notch corrosion of 0.6 mm was observed at a dry-film thickness of D1 and an anti-corrosion pigment content of 10%. 相似文献
709.
Dejan Reljic Walburga Dieterich Hans J. Herrmann Markus F. Neurath Yurdagül Zopf 《Nutrients》2022,14(10)
Exercise is a cornerstone in metabolic syndrome (MetS) treatment. However, the effects of low-volume exercise modalities on MetS-associated low-grade inflammation are unclear. A total of 106 MetS patients (53.7 ± 11.4 years) were randomized to low-volume high-intensity interval training (LOW-HIIT, 14 min/session), single-set resistance training (1-RT, ~15 min/session), whole-body electromyostimulation (WB-EMS, 20 min/session), three-set resistance training (3-RT, ~50 min/session), each performed 2 ×/week for 12 weeks, or a control group (CON). All groups received nutritional counseling for weight loss. Inflammatory and cardiometabolic indices were analyzed pre- and post-intervention. All groups significantly reduced body weight by an average of 3.6%. Only LOW-HIIT reduced C-reactive protein (CRP) (−1.6 mg/L, p = 0.001) and interleukin-6 (−1.1 pg/mL, p = 0.020). High-sensitivity CRP and lipopolysaccharide-binding protein decreased following LOW-HIIT (−1.4 mg/L, p = 0.001 and −2.1 ng/mL, p = 0.004) and 3-RT (−0.6 mg/L, p = 0.044 and −2.0 ng/mL, p < 0.001). MetS severity score improved with LOW-HIIT (−1.8 units, p < 0.001), 1-RT (−1.6 units, p = 0.005), and 3-RT (−2.3 units, p < 0.001). Despite similar effects on body weight, low-volume exercise modalities have different impact on inflammatory and cardiometabolic outcomes in MetS patients. LOW-HIIT has superior efficacy for improving inflammation compared to 1-RT and WB-EMS. Resistance-based exercise appears to require a higher volume to promote beneficial impact on inflammation. 相似文献
710.
Milo ankovi Milan Tei Marija Jevti Dejan Stevanovi Milan B Jovanovi Dejan Kosti Jadranka Anti Sanja Krejovi Trivi 《Medicina oral, patología oral y cirugía bucal》2022,27(4):e340
Background The aim of this study was to identify predictors of the Health-Related Quality of Life (HRQoL) in patients with head and neck cancers (HNCs).Material and Methods In total, 345 patients with HNCs were interviewed. A self-report questionnaire was administered to collect data about demographic characteristics, health status, smoking, alcohol consumption habits, and HRQoL. It were used the EORTC Instruments - Quality of Life Questionnaire-Core 30-questions (QLQ-C30), Quality of Life Questionnaire - Head and Neck Module 35-questions (QLQ-H&N 35) and OHIP-14 instrument for HRQoL assessments. Clinical information and treatment data were collected from medical records.Results Five groups of HRQoL predictors were identified: demographic, socioeconomic, behavioral, psychophysical, and clinical/treatment. These HRQoL predictors had a strong (i.e., age, level of social support and social contact, level of education, depression, fatigue, presence of gastrostomy, comorbidities, and use of pain medications and supplements), a moderate (i.e., marital status, smoking, sexuality problems, time since diagnosis, presence of tracheostomy, and side effects outcomes of radio and chemotherapy) and a small impact (i.e., employment/financial difficulties, tumor site and stage, and surgical procedure).Conclusions Study identified nineteen predictors that had significant, moderate and small impact on the HRQoL of patients with HNCs. Some of the predictors, like levels of social support and social contact, depression, and comorbidities could be targets for innervations to improve HRQoL. Key words:Quality of Life, oral health, combined modality therapy, treatment outcome. 相似文献