Effects of Zinc Supplement on Plasma Homocysteine Level in End-Stage Renal Disease Patients: a Double-Blind Randomized Clinical Trial

Increased homocysteine (hCys) level is an independent risk factor for cardiovascular complications in end-stage renal disease (ESRD) patients. The aim of this study was to evaluate effect of zinc (Zn) supplement on serum hCys level in ESRD patients. One hundred ESRD patients with Zn deficiency were enrolled in this double-blind randomized clinical trial. They were randomly subdivided into two groups and supplemented with Zn (Zn group) or placebo (control group) for 6 weeks. Fasting plasma hCys and Zn levels were measured before and at 43rd days after the start of the study. Serum Zn levels increased significantly (p?<?0.0001), in Zn-treated group in comparison to placebo-treated group. In the Zn-treated group, serum hCys levels reduced significantly (p?<?0.0001), compared to placebo group (p?>?0.05). There was a significant (p?<?0.0001) reduction of mean percentage of hCys in Zn-treated group compared to the placebo group. Our study showed that Zn supplementation decreases serum hCys levels in ESRD patients with Zn deficiency.     

Diminished Selenium Levels in Hemodialysis and Continuous Ambulatory Peritoneal Dialysis Patients

In this cross-sectional study, selenium (Se) levels in the sera of 35 hemodialysis (HD) patients and 34 patients undergoing continuous ambulatory peritoneal dialysis (CAPD) for more than 3 months were compared with the serum Se levels of 34 healthy volunteers. The observed Se levels of 100.8 ± 51.9 μg/L in the sera of the HD patients and of 65.5 ± 32.1 μg/L in the sera of the CAPD patients were significantly lower than the 134.9 ± 81.2 μg/L of the controls, with p = 0.002 and 0.02, respectively. Furthermore, the Se levels were significantly higher in the HD rather than the CAPD patients (p = 0.01). In the spent dialysate effluent fluid of 32 of the CAPD patients Se was undetectable, in the remaining two CAPD patients the Se levels were 1.9 and 4.6μg/l, respectively. The low Se levels of HD and CAPD patients as compared to healthy persons are attributed to diminished Se retention due to chronic oxidative stress.     

Association between Tissue Expression of Toll-Like Receptor and Some Clinicopathological Indices in Oral Squamous Cell Carcinoma

Background:The oral squamous cell carcinoma (OSCC) composes about 90% of all head and neck cancers. The toll-like receptor (TLR)⁺ immune cells have potential of invasion and malignancy transformation. The aim of this study was assessment of possible associations between clinicopathological indices and TLR2 and TLR9 gene expression in OSCC.Methods:Forty-two OSCC samples with related healthy margins including 25 early and 17 advanced stages were gathered. The samples were classified histologically from grade I to II. The expression of TLR2 and TLR2 was evaluated by Real-time PCR. The patient’s disease-free survival (DFS) and overall survival (OS) were analyzed using SPSS V.23 software.Results:The expression of TLR2 and TLR9 genes in tumor tissues (especially in grade I and II) were higher than healthy surgical margin tissue (p< 0.001). TLR9 expression in grade II was statistically significant than grade I in tumor tissue (p< 0.001). TLR9 expression in advanced stage was statistically significant in compare to early stage (p= 0.012). In advanced stage both overall survival (p= 0.029) and disease-free survival (p= 0.012) were statistically lower than early stage. The follow-up time to recurrence in advanced stage was statistically lower than early stage (p= 0.007).Conclusion:Overexpression of TLRs 2, 9 play role in the pathogenesis and tumor development of OSCC and can be applied as biomarker in prognostic approaches.Key Words: Disease-free survival, Oral squamous cell carcinoma, Overall survival, TLR2, TLR9     

Terahertz Plasmonic Quantum Cascade Lasers: a Comprehensive Physics Study

Generation of terahertz (THz) radiation has been a hot research topic in recent years. Plasmonic quantum cascade lasers (QCLs) are among the most compact and efficient sources to generate THz radiation. In this paper, we comprehensively study plasmonic QCLs designed based on the antenna-feedback structure to generate efficient radiation about the center frequency of 3 THz. By changing the geometric structure of the plasmonic cavity and using two-dimensional simulation, a minimum loss less than 5.9 cm^?1 is achieved at the lasing frequency. It is also possible to control the orientation of the output beam either vertically or tilted by changing the geometry of the antenna design via chirped or non-chirped grating scheme. Moreover, the output characteristics of the QCL are simulated based on the three-level rate equations through which the dynamics of the laser, as well as the P-I curve, are investigated. Also, the gain spectra for two laser designs (with chirped and non-chirped gratings) are simulated and compared to each other. The results of this paper may provide deep insight into designing efficient laser sources in the THz region.