Preparation of a manganese titanate nanosensor: Application in electrochemical studies of captopril in the presence of para-aminobenzoic acid

This study reports the synthesis and characterization of a novel nanostructure-based electrode for electrochemical studies and determination of captopril (CP). At first manganese titanate nanoceramics were synthesized by the sol–gel method. The structural evaluations of the pure nanopowders were investigated by different techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Then it was used to prepare a new nanostructured manganese titanate carbon paste electrode (MnTiO₃/CPE). The characterization of the modified sensor was carried out by comprehensive techniques such as electrochemical impedance spectroscopy (EIS), SEM, and voltammetry. Subsequently, the modified electrode was used for CP catalytic oxidation in the presence of para-aminobenzoic acid (PABA) as a mediator. The results showed that PABA has high catalytic activity for CP oxidation. The electrochemical behavior of CP was studied by cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CHA), and differential pulse voltammetry (DPV) techniques. Under the optimized conditions, the catalytic oxidation peak current of CP showed two linear dynamic concentration ranges of 1.0 × 10⁻⁸ to 1.0 × 10⁻⁷ and 1.0 × 10⁻⁷ to 1.0 × 10⁻⁶, with a detection limit of 1.6 nM (signal/noise = 3), using the DPV technique. Finally, the proposed method was successfully applied for determination of CP in pharmaceutical and biological samples.     

Microsatellite analysis of Damask rose (<Emphasis Type="Italic">Rosa damascena</Emphasis> Mill.) accessions from various regions in Iran reveals multiple genotypes

Background  

Damask roses (Rosa damascena Mill.) are mainly used for essential oil production. Previous studies have indicated that all production material in Bulgaria and Turkey consists of only one genotype. Nine polymorphic microsatellite markers were used to analyze the genetic diversity of 40 accessions of R. damascena collected across major and minor rose oil production areas in Iran.     

In silico studying of the whole protein structure and dynamics of Dickkopf family members showed that N-terminal domain of Dickkopf 2 in contrary to other Dickkopfs facilitates its interaction with low density lipoprotein receptor related protein 5/6

Wnt (Wingless Int) signaling pathway has been known to be dysregulated in several human cancers, especially colorectal cancer (CRC). The Dickkopf (DKK) family which consists of four secreted proteins in vertebrates (DKK 1, 2, 3, 4) is one of the most critical antagonist families for Wnt signaling pathway. They typically antagonize Wnt/β-catenin signaling by binding and inhibiting Wnt co-receptors, LRP5/6 (low density lipoprotein receptor related protein 5/6). However, except for DKK1 (Dickkopf 1), details about structure and function of the members of this family are poorly defined. In this study, main Dickkopf family members were analyzed structurally, using protein structure prediction tools, molecular dynamics (MD), molecular docking and energy analyses. Three dimensional structure of whole DKKs was predicted and their interaction with LRP6 was investigated in detail. The results indicated that in DKK family members, a considerable diversity, in the case of structure, activity and physicochemical properties was seen. This diversity was more profound in DKK3 (Dickkopf3). Interestingly, the interaction mode of DKK2 (Dickkopf2) with its receptor, LRP6, was shown to be substantially different from other Dickkopf family members while N-terminal region of this ligand was also involved in the binding to the LRP6-P3P4. Moreover, the cysteine-rich domain 2 (CRD2) of DKK1 and DKK3 had a higher binding affinity to LRP6 in comparison with the whole protein structures.

Communicated by Ramaswamy H. Sarma     

The role of miRNA-377 as a tumor suppressor in lung cancer by negative regulation of genes belonging to ErbB signaling pathway

Molecular Biology Reports - The ErbB signaling pathway plays important role in the pathogenesis of lung cancer. We explored the role of miRNA-377 as a tumor suppressor in NSCLC through silencing of...     

The prevalence of plasmid-mediated quinolone resistance genes among Escherichia coli strains isolated from urinary tract infections in southwest Iran

Molecular Biology Reports - The extensive and inappropriate use of quinolones, which are frequently used as an effective treatment for urinary tract infection (UTI) patients, has led to resistance...     

Comparison between the cultures of human induced pluripotent stem cells (hiPSCs) on feeder-and serum-free system (Matrigel matrix), MEF and HDF feeder cell lines

Human induced pluripotent stem cells (hiPSCs) are a type of pluripotent stem cells artificially derived from an adult somatic cell (typically human fibroblast) by forced expression of specific genes. In recent years, different feeders like inactivated mouse embryonic fibroblasts (MEFs), human dermal fibroblasts (HDFs), and feeder free system have commonly been used for supporting the culture of stem cells in undifferentiated state. In the present work, the culture of hiPSCs and their characterizations on BD Matrigel (feeder-and serum-free system), MEF and HDF feeders using cell culture methods and molecular techniques were evaluated and compared. The isolated HDFs from foreskin samples were reprogrammed to hiPSCs using gene delivery system. Then, the pluripotency ability of hiPSCs cultured on each layer was determined by teratoma formation and immunohistochemical staining. After EBs generation the expression level of three germ layers genes were evaluated by Q-real-time PCR. Also, the cytogenetic stability of hiPSCs cultured on each condition was analyzed by karyotyping and comet assay. Then, the presence of pluripotency antigens were confirmed by Immunocytochemistry (ICC) test and alkaline phosphatase staining. This study were showed culturing of hiPSCs on BD Matrigel, MEF and HDF feeders had normal morphology and could maintain in undifferentiated state for prolonged expansion. The hiPSCs cultured in each system had normal karyotype without any chromosomal abnormalities and the DNA lesions were not observed by comet assay. Moreover, up-regulation in three germ layers genes in cultured hiPSCs on each layer (same to ESCs) compare to normal HDFs were observed (p < 0.05). The findings of the present work were showed in stem cells culturing especially hiPSCs both MEF and HDF feeders as well as feeder free system like Matrigel are proper despite benefits and disadvantages. Although, MEFs is suitable for supporting of stem cell culturing but it can animal pathogens transferring and inducing immune response. Furthermore, HDFs have homologous source with hiPSCs and can be used as feeder instead of MEF but in therapeutic approaches the cells contamination is a problem. So, this study were suggested feeder free culturing of hiPSCs on Matrigel in supplemented media (without using MEF conditioned medium) resolves these problems and could prepare easy applications of hiPSCs in therapeutic approaches of regenerative medicine such as stem-cell therapy and somatic cell nuclear in further researches.     

Incidence of exercise-associated hyponatremia during a high-altitude 161-km ultramarathon

[Purpose]Exercise-associated hyponatremia (EAH) is a well-known condition among endurance athletes at low altitudes. The incidence of EAH during ultramarathons at high altitudes warrants further investigation. This prospective observational study was conducted on the participants of the Leadville Trail 100 run, a 161-km race held at a high altitude (2,800 m-3,840 m).[Methods]Venous blood samples were collected before and immediately after the race. The participants completed an electronic survey after the race. Our main outcome measure was the post-race serum sodium ([Na⁺]) level.[Results]Of the 672 athletes who started the race, 351 (52%) successfully completed the event within the 30-hour cut-off. Post-race blood samples were collected from 84 runners (66 finishers). Both pre- and post-race blood samples were collected from 37 participants. Twenty percent of the post-race participants had EAH. Only one post-race participant had a [Na⁺] level of <130 mmol/L. All participants with EAH were asymptomatic. One participant had an abnormal pre-race [Na⁺] level (134 mmol/L). Female participants had a significantly higher rate of EAH than male participants (40% vs. 16%; p=0.039). Age, body mass index, weight changes, race completion status, nonsteroidal anti-inflammatory drug use, and urine specific gravity were not associated with the development of EAH. Lower postrace [Na⁺] levels were associated with higher serum creatine kinase values (R²=0.1, p<0.005).[Conclusion]High altitude (3,840 m peak) does not appear to enhance the incidence of EAH after an ultramarathon footrace. This suggests that ambient temperature (low temperatures reduce risk), sex (female predilection), endurance running, and overhydration are more prominent risk factors for EAH than high altitude.     

Association of IL-15 and IP-10 Serum Levels with Cytomegalovirus Infection,CMV Viral Load and Cyclosporine Level after Kidney Transplantation

Background:Cytomegalovirus (CMV) infection is the most common complications following kidney transplantation. Natural killer (NK) cells demonstrated critical anti-viral role in controlling and elimination of CMV after transplantation. Interleukin-15 (IL-15) is a pleiotropic cytokine that promotes the activity of NK cells and strengthens the acquired immune system. Also, IP10 (CXCL10) is a chemotactic factor which regulates NK cell recruitment and antiviral immune response. We aimed to determine the correlation between the serum levels of IL-15 and IP-10 cytokines with CMV infection, CMV viral load, and cyclosporine as a major immunosuppressive treatment after transplantation.Methods:Fifty-eight kidney transplant recipient patients without evidence of CMV virus disease before transplantation surgery were included in the study. From the day of transplant surgery, the patients were evaluated based on the presence of CMV Ag pp65, CMV viral load, serum levels of IL-15 & IP-10, Cyclosporine levels (C0 & C2), Glomerular Filtration Rate (GFR), and hematological & biochemical Index, up to 75 days.Results:Comparison analysis of serum levels of IL-15 and IP-10 showed no significant association with CMV infection in kidney transplant recipients. In addition, CMV viral load and cyclosporine levels at C0 and C2 did not affect patients'' IL-15 and IP-10 levels.Conclusion:The levels of IP-10 and IL-15 cytokines are not affected with CMV infection, even if a viral infection occurs in the early days after transplantation or long afterwards. In addition, taking the different levels of cyclosporine did not affect the cytokines levels. Other mechanisms may play a role in maintaining the levels of these cytokines.Key Words: Cytokine, Cytomegalovirus, IP-10, Interleukin-15, Transplantation