Ethanolic extract of Brazilian green propolis sensitizes prostate cancer cells to TRAIL-induced apoptosis

Prostate cancer represents an ideal disease for chemopreventive intervention. Propolis possesses immuno-modulatory, anti-tumour and chemopreventive properties. The tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is an important endogenous anti-cancer agent that induces apoptosis selectively in tumour cells. However, some cancer cells are resistant to TRAIL-mediated apoptosis. Naturally occurring phenolic and polyphenolic compounds sensitize TRAIL-resistant cancer cells and augment the apoptotic activity of TRAIL. The ethanolic extract of Brazilian green propolis (EEP) is rich in phenolic components. Our in vitro results indicate the potential targets in the TRAIL-induced apoptotic pathway for the cancer chemopreventive activity of Brazilian propolis. We examined the cytotoxic and apoptotic effects of Brazilian EEP and its bioactive components in combination with TRAIL on LNCaP prostate cancer cells. The chemical composition of Brazilian green propolis was determined by high performance liquid chromatography-diode array detection. The cytotoxicity was measured by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl-tetrazolium and lactate dehydrogenase assays. Apoptosis was detected using annexin V-FITC by flow cytometry and fluorescence microscopy. The mitochondrial membrane potential (?Ψm) was evaluated using DePsipher staining by fluorescence microscopy. Flow cytometry was used to analyse death receptor (TRAIL-R1 and TRAIL-R2) expression in LNCaP cells. The inhibition of nuclear factor-κB (NF-κB) (p65) activation in cancer cells was confirmed by the ELISA-based TransAM NF-κB kit. The LNCaP cells were shown to be resistant to TRAIL-induced apoptosis. Our study demonstrates that EEP sensitizes TRAIL-resistant prostate cancer cells. The main phenolic components detected in Brazilian green propolis are artepillin C, quercetin, kaempferol and p-coumaric acid. Brazilian propolis and its bioactive components markedly augmented TRAIL-mediated apoptosis and cytotoxicity in prostate cancer cells. Brazilian EEP enhanced the expression of TRAIL-R2 and the activity of NF-κB in LNCaP cells. The co-treatment of prostate cancer cells with 100 ng/ml TRAIL and 50 μg/ml EEP increased the percentage of apoptotic cells to 65.8 ± 1.2% and caused a significant disruption of ?Ψm in LNCaP cells. We show that Brazilian EEP helped cells overcome TRAIL resistance by engaging both intrinsic and extrinsic apoptotic pathways and regulating NF-κB activity. The data demonstrate the important role of Brazilian green propolis and its bioactive compounds in prostate cancer chemoprevention through the enhancement of TRAIL-mediated apoptosis.     

Five-year Follow-up of a Randomized Clinical Trial of Total Thyroidectomy versus Dunhill Operation versus Bilateral Subtotal Thyroidectomy for Multinodular Nontoxic Goiter

Background  

The extent of thyroid resection in multinodular nontoxic goiter (MNG) is controversial. The aim of the present study was to evaluate results of various thyroid resection modes, with special emphasis put on the recurrence rate and morbidity rate, in a 5-year follow-up.     

Value of Transthoracic Echocardiography for the Detection of High-Grade Coronary Artery Stenosis: Prospective Evaluation in 50 Consecutive Patients Scheduled for Coronary Angiography

We prospectively evaluated the feasibility of direct, transthoracic evaluation of coronary arteries to diagnose flow-limiting lesions. Second harmonic mode in B-mode and fundamental mode for Doppler examinations was used. A stenosis was diagnosed when maximal flow velocity at least doubled in comparison with that of the adjacent segment or when local velocity was at least 2 m/s. Of the left anterior descending coronary artery segments assessed, 34 were proximal, 35 middle, and 34 distal segments. The corresponding figures for circumflex coronary artery segments were 17 proximal and 11 middle segments and for the right coronary artery, 14 proximal and 15 distal segments. No distal circumflex and only 1 mid right coronary artery segment was visualized. Twenty-eight stenoses were diagnosed. Specificity for stenosis detection was 96% to 100% and sensitivity was 62% to 66%. Echo-cardiography was unable to document occlusions. Transthoracic echocardiography allows for coronary artery assessment in a significant portion of patients scheduled for coronary angiography. It may be used to document the presence of coronary artery stenosis. With further technologic improvements, transthoracic echocardiography could enable the monitoring of the restenosis process after percutaneous transluminal coronary angioplasty/stent intervention and coronary artery luminal narrowing after heart transplantation.     

Structural Properties of Thin ZnO Films Deposited by ALD under O-Rich and Zn-Rich Growth Conditions and Their Relationship with Electrical Parameters

The structural, optical, and electrical properties of ZnO are intimately intertwined. In the present work, the structural and transport properties of 100 nm thick polycrystalline ZnO films obtained by atomic layer deposition (ALD) at a growth temperature (T_g) of 100–300 °C were investigated. The electrical properties of the films showed a dependence on the substrate (a-Al₂O₃ or Si (100)) and a high sensitivity to T_g, related to the deviation of the film stoichiometry as demonstrated by the RT-Hall effect. The average crystallite size increased from 20–30 nm for as grown samples to 80–100 nm after rapid thermal annealing, which affects carrier scattering. The ZnO layers deposited on silicon showed lower strain and dislocation density than on sapphire at the same T_g. The calculated half crystallite size (D/2) was higher than the Debye length (L_D) for all as grown and annealed ZnO films, except for annealed ZnO/Si films grown within the ALD window (100–200 °C), indicating different homogeneity of charge carrier distribution for annealed ZnO/Si and ZnO/a-Al₂O₃ layers. For as grown films the hydrogen impurity concentration detected via secondary ion mass spectrometry (SIMS) was 10²¹ cm⁻³ and was decreased by two orders of magnitude after annealing, accompanied by a decrease in Urbach energy in the ZnO/a-Al₂O₃ layers.     

Prognostic value of average T-wave alternans and QT variability for cardiac events in MADIT-II patients

Background

Identifying which patients might benefit the most from ICD therapy remains challenging. We hypothesize that increased T-wave alternans (TWA) and QT variability (QTV) provide complementary information for predicting appropriate ICD therapy in patients with previous myocardial infarction and reduced ejection fraction.

Methods

We analyzed 10-min resting ECGs from MADIT-II patients with baseline heart rate > 80 beats/min. TWA indices IAA and IAA₉₀ were computed with the multilead Laplacian Likelihood ratio method. QTV indices QTVN and QTVI were measured using a standard approach. Cox proportional hazard models were adjusted considering appropriate ICD therapy and sudden cardiac death (SCD) as endpoints.

Results

TWA and QTV were measured in 175 patients. Neither QTV nor TWA predicted SCD. Appropriate ICD therapy was predicted by combining IAA₉₀ and QTVN after adjusting for relevant correlates.

Conclusion

Increased TWA and QTV are independent predictors of appropriate ICD therapy in MADIT-II patients with elevated heart rate at baseline.     

Eicosanoids in exhaled breath condensate and BAL fluid of patients with sarcoidosis

BACKGROUND: Measurement of inflammatory mediators in exhaled breath condensate (EBC) is an easy and noninvasive diagnostic method, which has gained popularity in the past few years. However, the source of these mediators is not precisely defined. It has been only presumed that inflammatory cells present in the airway lumen are the main source. Therefore, the aim of this study was to verify the relationship between EBC and BAL fluid (BALF) eicosanoids, and the percentage, number, and activity of cells in BALF. METHODS: In 28 sarcoidosis patients and 17 healthy subjects, 8-isoprostane, cysteinyl leukotrienes (CysLTs), and leukotriene B4 (LTB4) were measured in EBC by enzyme immunoassay. Eicosanoids were also examined in BALF in the study group. Cell count, percentage, and superoxide production by BALF cells were estimated. RESULTS: The mean (+/- SEM) CysLT and 8-isoprostane concentrations were higher in the sarcoidosis group (6.5 +/- 0 vs 27.82 +/- 6.65 pg/mL, respectively; and 2.67 +/- 0.16 vs 13.95 +/- 2.59 pg/mL, respectively). There were positive correlations between EBC and BALF 8-isoprostane concentration (r = 0.68, p < 0.0001) and LTB4 concentration (r = 0.43; p = 0.026). EBC LTB4 levels correlated with the number of lymphocytes per milliliter of BALF. The percentage and number of eosinophils in BALF correlated with EBC 8-isoprostane and BALF CysLT concentrations. No positive correlation was found between concentrations of EBC eicosanoids and percentages BALF lymphocytes, BALF macrophages, or superoxide production. CONCLUSIONS: The levels of 8-isoprostane and CysLT are elevated in EBC in sarcoidosis patients; however, a lack of correlation with BALF lymphocyte percentage does not encourage us to recommend the measurement of eicosanoids as activity markers. The positive correlation of EBC 8-isoprostane and BALF CysLT concentrations with the percentage of eosinophils in BALF, and the higher percentage of eosinophils in BALF from patients with grade 3 sarcoidosis, may suggest the possible prognostic value.     

Evolving approach to aortic valve replacement in children and adolescents--a preliminary report

BACKGROUND: Surgical treatment methods are still controversial in children with congenital or acquired aortic valve dysfunction. AIM: To evaluate treatment results in children after mechanical or biological valve implantation. METHODS: We analysed a group of 55 children after mechanical valve implantation (group A) and a group of 8 children after Freestyle biological valve implantation (group B). We evaluated in both groups: patient's age, type of valve dysfunctions, severity of heart failure symptoms, and quality of life. The parameters of physiological left ventricular (LV) remodelling were examined on the basis of echocardiographical signs of LV contractibility (%SF) and anatomical changes: LV diastolic diameter (LVDd), LV posterior wall thickness (LVPW), thickness of intra-ventricle septum (IVS) and pressure gradient between LV and aorta (LV-Ao). RESULTS: There were no hospital deaths in either group. There were two late deaths in children from group A. Thromboembolic (2), nonspecific bleeding complications (2), and infections (2) occurred in group A. There were two re-operations in children after mechanical valve implantation. The early postoperative period was good in groups A and B. Furthermore, late postoperative period was good in group B. Physiological LV remodelling occurred in children in groups A and B. Quality of life was good in both groups. CONCLUSIONS: Good clinical results, simplicity, repeatability and safety of surgical technique mean that mechanical valve implantation in the aortic position is still an attractive option for treatment in children and adults. However, absence of bleeding, thromboembolic and infection complications and improvement of durability mean that the Freestyle biological new generation valve could be a good option for future in children and adolescents who need aortic valve replacement.