Multiple interactions between melatonin and non-coding RNAs in cancer biology

The melatonin hormone secreted by the pineal gland is involved in physiological functions such as growth and maturation, circadian cycles, and biological activities including antioxidants, anti-tumor, and anti-ischemia. Melatonin not only interacts with proteins but also has functional effects on regulatory RNAs such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs). In this study, we overview various physiological and pathological conditions affecting melatonin through lncRNA and miRNA. The information compiled herein will serve as a solid foundation to formulate ideas for future mechanistic studies on melatonin. It will also provide a chance to more clarify the emerging functions of the non-coding transcriptome.

The roles of signaling pathways in liver repair and regeneration

The liver has remarkable regeneration potency that restores liver mass and sustains body hemostasis. Liver regeneration through signaling pathways following resection or moderate damages are well studied. Various cell signaling, growth factors, cytokines, receptors, and cell types implicated in liver regeneration undergo controlled hypertrophy and proliferation. Some aspects of liver regeneration have been discovered and many investigations have been carried out to identify its mechanisms. However, for optimizing liver regeneration more should be understood about mechanisms that control the growth of hepatocytes and other liver cell types in adults. The current paper deals with the possible applicability of liver regeneration signaling pathways as a target for therapeutic approaches and preventing various liver damages. Furthermore, the latest findings of spectrum-specific signaling pathway mechanisms that underlie liver regeneration are briefly described.

In vitro evaluation of the sealing ability of three newly developed root canal sealers: A bacterial microleakage study

Background

The purpose of this study was to compare the sealing ability of MTA Fillapex, Apatite Root Canal Sealer and AH26 sealers.

Material and Methods

The present in vitro study was carried out on 142 extracted single-rooted human mature teeth. The teeth were randomly divided into three experimental groups (n=44) and two control groups (n=5). Three root canal sealers were MTA Fillapex, Apatite Root Canal Sealer and AH26. The teeth in the control groups were either filled with no sealer or made completely impermeable. The root canals were prepared and obturated with gutta-percha and one of the sealers. The teeth were sterilized with ethylene oxide gas prior to the bacterial leakage assessment using Enterococcus faecalis. Leakage was evaluated every 24 hours for 90 days. Data were analyzed with descriptive statistical methods and chi-squared test. If the data were significant, a proper post hoc test was used. Statistical significance was set at P<0.05.

Results

The positive control specimens exhibited total bacterial penetration whilst the negative control specimens showed no evidence of bacterial penetration. At the end of the study, the analysis of microleakage with chi-squared test showed no significant differences between the experimental groups (P<0.05). The results of chi-squared test analyzing the pair-wise differences between the groups considering the numerical values for leakage day indicated the lowest leakage with AH26 and the highest with Apatite root sealer.

Conclusions

According to the results of the present study, sealing ability of AH26 was significantly higher than that of MTA Fillapex and Apatite Root Canal Sealer.

Key words:Mineral Trioxide aggregate, root canal obturation, dental seal.

Association of Promoter Polymorphisms of Interleukin-10 and Interferon-Gamma Genes with Tuberculosis in Azeri Population of Iran

Promoter polymorphism of cytokine genes may lead to inter-individual differences in cytokine levels, therefore, polymorphisms may associate with susceptibility to infectious diseases. In this study, we investigated a possible association between interleukin-10 (IL-10) -1082A⁄G (rs1800896) and interferon (IFN)-gamma +874T/A (rs2430561) promoter polymorphisms and tuberculosis (TB) in the Azeri population of Iran. IL-10 -1082G/A and IFN-gamma +874T/A single nucleotide polymorphisms (SNPs) were genotyped by amplification refractory mutation system (ARMS)-PCR in 200 healthy controls and 124 tuberculosis patients. IL-10 -1082 A allele was more frequent in the control group than in the patient group (p=0.001, odds ratio [OR]=2.183). On the other hand, the AA genotype was significantly more frequent in the control group (p=0.0001). The frequency of IFN-gamma +874 T allele was significantly higher in the controls (p=0.013, OR=1.56). There was no significant association between IFN-gamma +874 T/A genotypes and susceptibility to tuberculosis (p=0.078), but TT genotype was more frequent in the control group. Our findings suggest that interleukin-10 -1082G/A polymorphism may play an important role in susceptibility to tuberculosis in our population. On the other hand, the +874T allele, which has been suggested to be associated with high IFN-gamma levels, was significantly higher in the controls and TT genotype was also more frequent in the control group. Thus, +874 T allele may be associated with resistance to tuberculosis in this Azeri population of Iran.