A Cross-Cultural Study: Middle School Students\u27 Beliefs about Matter

Turkish middle school students’ understanding of the nature of matter was examined and compared to those of US counterparts. Sixteen Turkish middle school students were interviewed using a semi-structured interview guide. The interview explored students’ understanding of the particulate nature of matter in three areas: (1) the composition of the substances; (2) the relationship between particulate structure and macroscopic properties; (3) the relationship between particulate structure and processes. The results indicated that many of the middle school students interviewed could state that matter was composed of atoms. However, the majority of them were not able to use this understanding to explain macroproperties or processes of matter. Compared to the US students, the Turkish students could use terms more appropriately in describing the microparticulate nature of matter. However, when students tried to explain the macroproperties or processes of matter, the US students offered more complex and detailed explanations

HDAC inhibitors, MS-275 and salermide, potentiates the anticancer effect of EF24 in human pancreatic cancer cells

Histone deacetylases (HDACs) play a major role in the regulation of chromatin structure and gene expression by changing acetylation status of histone and non-histone proteins. MS-275 (entinostat, MS) is a well-known benzamide-based HDACI and Salermide (SAL), a reverse amide compound HDACI, have antiproliferative effects on several human cancer cells. In this study, we aimed to investigate the effects of HDACIs (MS and SAL) alone and/or combined use with EF24 (EF), a novel synthetic curcumin analog, on human pancreatic cancer cell line (BxPC-3). In vitro, BxPC-3 cells were exposed to varying concentrations of MS, SAL with or without EF, and their effects on cell viability, acetylated Histone H3 and H4 levels, cytotoxicity, and cleaved caspase 3 levels, and cell cycle distribution were measured. The viability of BxPC-3 cells decreased significantly after treatment with EF, MS and SAL treatments. MS and SAL treatment increased the acetylation of histone H3 and H4 in a dose dependent manner. MS and SAL alone or combined with EF were increased the number of cells in G1 phase. In addition, treatment with agents significantly decreased the ratio of cell in G2/M phase. There were significant dose-dependent increases at cleaved Caspase 3 levels after MS treatment but not after SAL treatment. Our results showed that HDAC inhibitors (MS and SAL), when combined with EF, may effectively reduce pancreatic cancer cell (BxPC-3) progression and stop the cell cycle at G1 phase. Further molecular analyses are needed to understand the fundamental molecular consequences of HDAC inhibition in pancreas cancer cells

Hemoglobin is inversely related to flow-mediated dilatation in chronic kidney disease

The microcirculation is regulated by oxygen gradients and by endothelial release of nitric oxide, which can react with hemoglobin to form S-nitroso derivatives. Here we induced flow-mediated dilatation of the brachial artery in response to ischemia in 141 non-diabetic patients with stage 3–4 chronic kidney disease who had no history of smoking, cardiovascular events or use of erythropoietin-based agents. Patients with hemoglobin concentrations above the cohort median of 11.6 g/dl were found to have significant reductions in flow-mediated dilatation compared to those below the median. This inverse relationship remained significant after adjustment for potential confounders, including insulin sensitivity, glomerular filtration rate, proteinuria, body mass index, serum urate, etiology of underlying renal disease, treatment with anti-hypertensive drugs, and traditional Framingham risk factors. Given that hemoglobin can act as an important nitric oxide carrier and buffer, our studies suggest that the mechanism by which hemoglobin influences the endothelium-dependent microcirculation requires its nitrosylation; however, more direct studies need to be performed

FGF-23 and vascular dysfunction in patients with stage 3 and 4 chronic kidney disease

Studies in animals show that fibroblast growth factor (FGF)-23 interferes with vascular reactivity induced by the nitric oxide (NO) system. To investigate the relationship between circulating FGF-23 levels and the response of forearm blood flow to ischemia (flow-mediated vasodilatation, FMD) and nitroglycerin, we tested 183 patients with stage 3-4 chronic kidney disease (CKD). None of them had cardiovascular complications or were taking drugs interfering with vascular function. Patients with FGF-23 levels above the median had significantly lower glomerular filtration rate, FMD, and fetuin-A levels (an anti-inflammatory molecule and potent inhibitor of calcification). They also had higher proteinuria and phosphate levels when compared to patients whose FGF-23 levels were below the median. The response to nitroglycerin was not different between the two groups. Multiple regression analysis showed that the relationship between FGF-23 and FMD was only modestly sensitive to adjustment for classical risk factors, biomarkers of bone mineral metabolism, high-sensitivity C-reactive protein, and homeostatic model assessment index. Adjustment for asymmetrical dimethyl arginine (ADMA) weakened the strength of this link; however, it remained highly significant. There was no independent association between FGF-23 and nitroglycerin. Thus, attenuation of FMD by ADMA suggests that this endogenous inhibitor of NO synthase may, in part, mediate the vascular effects of FGF-23 in patients with CKD. © 2010 International Society of Nephrology

Endothelial function in patients with familial Mediterranean fever-related amyloidosis and association with cardiovascular events

Objectives. Secondary amyloidosis is the most important complication of FMF and endothelial function is more severely impaired. Elevated asymmetric dimethyl arginine (ADMA) may mediate the excess cardiovascular disease (CVD) risk of this group. We aimed to compare endothelial function characteristics, including ADMA, in patients with FMF-related amyloidosis and primary glomerulopathies and to define risk factors for a CVD event. Methods. We undertook a cross-sectional study with prospective follow-up including consecutive patients with FMF-related amyloidosis (n = 98) or other non-diabetic glomerulopathies (n = 102). All patients had nephrotic-range proteinuria and normal glomerular filtration rate. Flow-mediated dilatation (FMD) was assessedand ADMA levels, CRP and pentraxin 3 (PTX3) were determined. Patients were followed for cardiovascular events. Results. Amyloidosis patients secondary to FMF showed higher levels of ADMA, CRP and PTX3 and lower FMD as compared with patients with other glomerulopathies. Cardiovascular events (n = 54) were registered during 3 years of follow-up. Increased ADMA levels and lower FMD were observed in patients with cardiovascular risk in both groups, but especially in individuals with amyloidosis.Conclusion. Patients with FMF-related amyloidosis have increased CVD event risk, probably related to the high ADMA levels, elevated inflammatory markers and decreased FMD measures observed in these patients

Efficacy of Er:YAG laser on periodontitis as an adjunctive non‐surgical treatment: A split‐mouth randomized controlled study

Aim To evaluate the adjunctive efficacy of Er:YAG laser use with mechanical scaling and root planing (SRP ) for non‐surgical treatment of periodontitis. Materials and Methods In a randomized, single‐blinded, controlled trial, 27 patients were recruited. Using a split‐mouth design, two quadrants were randomly allocated into either a test group or a control group. The test quadrants received Er:YAG laser (ERL ; 100 mJ /pulse; 15 Hz to hard tissue and 50 mJ /pulse; 30 Hz to soft tissue) plus SRP treatment, while the control quadrants received SRP only. We evaluated periodontal indexes, including probing depth (PD ), clinical attachment level (CAL ), bleeding index (BI ), and plaque index (PLI ) at baseline, 3 months, and 6 months. Results The PD and CAL means in the ERL + SRP group were significantly lower than those in the SRP group at 3‐month follow‐up (PD : 2.98 ± 0.38 mm vs. 3.09 ± 0.35 mm; CAL : 4.51 ± 0.69 mm vs. 4.72 ± 0.67 mm) and 6‐month follow‐up (PD : 2.91 ± 0.31 mm vs. 3.02 ± 0.30 mm; CAL : 4.52 ± 0.65 mm vs. 4.72 ± 0.66 mm; p = 0.03 for both PD and CAL ). There were no significant differences in BI and PLI between two groups. Conclusions The Er:YAG laser treatment combined with conventional SRP significantly improved PD and CAL compared to SRP therapy alone; however, these differences were very small and, as a result, the adjunctive effect of Er:YAG laser is likely to be minimal clinically important