Association of IL-1 gene polymorphisms with chronic rhinosinusitis with and without nasal polyp

BACKGROUND: Chronic rhinosinusitis (CRS) is one of the most common and complex chronic inflammatory disease of sinonasal mucosa. Even though the pathogenesis of CRS is multifactorial and still unclear, the role of cytokines especially interleukin-1 (IL-1) is being investigated worldwide in different population because of varying results obtained. OBJECTIVE: To study the association of IL-1 (A and B) gene polymorphisms with chronic rhinosinusitis with nasal polyp (CRSwNP) and without nasal polyp (CRSsNP), and other factors related. METHODS: This is a case-controlled study which include a total of 138 subjects recruited from Otorhinolaryngology-Head and Neck Surgery clinic in Hospital Universiti Sains Malaysia. Genotyping of the IL-1A (+4845G, +4845T) and IL-1B (−511C, −511T) were performed with restriction fragment length polymorphism analysis. RESULTS: There was a statistical significant association between IL-1B (−511C, −511T) polymorphism with CRSwNP and CRSsNP (p 0.95, and 0.254, respectively). CONCLUSION: This study indicates an association of IL-1B (−511C, −511T) polymorphism with CRSwNP and CRSsNP in our population, hence there is a possibility of IL-1B involvement in modulating pathogenesis of CRS. There was no significant association of IL-1A (+4845G, +4845T) polymorphism with CRSwNP and CRSsNP, and other factors related.

Effects of perivitelline fluid obtained from horseshoe crab on the proliferation and genotoxicity of dental pulp stem cells

Perivitelline fluid [PVF] of the horseshoe crab embryo has been reported to possess an important role during embryogenesis by promoting cell proliferation. This study aims to evaluate the effect of PVF on the proliferation, chromosome aberration [CA] and mutagenicity of the dental pulp stem cells [DPSCs]. This is an in vitro experimental study. PVF samples were collected from horseshoe crabs from beaches in Malaysia and the crude extract was prepared. DPSCs were treated with different concentrations of PVF crude extract in an 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide [MTT] assay [cytotoxicity test]. We choose two inhibitory concentrations [IC[50] and IC[25]] and two PVF concentrations which produced more cell viability compared to a negative control [100%] for further tests. Quantitative analysis of the proliferation activity of PVF was studied using the AlamarBlue[Registered sign] assay for 10 days. Population doubling times [PDTs] of the treatment groups were calculated from this assay. Genotoxicity was evaluated based on the CA and Ames tests. Statistical analysis was carried out using independent t test to calculate significant differences in the PDT and mitotic indices in the CA test between the treatment and negative control groups. Significant differences in the data were P<0.05. A total of four PVF concentrations retrieved from the MTT assay were 26.887 mg/ml [IC[50]], 14.093 mg/ml [IC[25]], 0.278 mg/ml [102% cell viability] and 0.019 mg/ml [102.5% cell viability]. According to the AlamarBlue[Registered sign] assay, these PVF groups produced comparable proliferation activities compared to the negative [untreated] control. PDTs between PVF groups and the negative control were insignificantly different [P>0.05]. No significant aberrations in chromosomes were observed in the PVF groups and the Ames test on the PVF showed the absence of significant positive results. PVF from horseshoe crabs produced insignificant proliferative activity on treated DPSCs. The PVF was non-genotoxic based on the CA and Ames tests

Telomeres and Oxidative Stress.

Telomeres are long repetitive DNA sequences of TTAGGG located at the end of the linear chromosomes and bound by shelterin proteins. Shelterin proteins function as the protection for the loop structure of telomere, which prevents the chromosome ends uncapped; resemble a DNA break and activates DNA repair mechanism. Telomere length is maintained by an enzyme called telomerase. There are several factors that can shorten the telomeres which include telomere attrition during cell division, deficiency of Rad 54, which is involved in DNA repair and the methylation of histones H3 and histones H4, which can diminish telomerase activity. Three major mechanisms which influence the telomere length are the end-replication problem, the action of C-strand-specific exonuclease and oxidative DNA damage induced by environmental risk factors. However, oxidative stress has been shown to be the major mechanism which can influence the telomere length. This review explores the association between telomere length a oxidative stress.

Extraction of mitochondrial DNA from tooth dentin: application of two techniques

Mitochondrial DNA (mtDNA) is a hereditary material located in mitochondria and is normally maternally inherited. Mutational analysis performed on mtDNA proved that the mutations are closely related with a number of genetic illnesses, besides being exploitable for forensic identification. Those findings imply the importance of mtDNA in the scientific field. MtDNA can be found in abundance in tooth dentin where it is kept protected by the enamel, the hardest outer part of the tooth. In this study, two techniques of mtDNA extraction were compared to determine the efficacy between the two techniques. Teeth used for the study was collected from Dental Clinic, Hospital Universiti Sains Malaysia. After the removal of tooth from the tooth socket of the patient, the tooth was kept at -20C until use. Later, pulp tissue and enamel was excised using dental bur and only the root dentin was utilized for the isolation of mtDNA by crushing it mechanically into powdered form. MtDNA was extracted using the two published methods, Pfeifer and Budowle and then subjected to spectrophotometry DNA quantification and purity, Polymerase chain reaction (PCR) amplification of hypervariable-two region of mtDNA, followed by DNA sequencing to analyze the reliability of the extraction techniques. In conclusion, both techniques proved to be efficient and capable for the extraction of mtDNA from tooth dentin.

Screening for XPD312 polymorphisms in human oral cancer: a preliminary study

Xeroderma pigmentosum-D (XPD) is one of the genes that play a role in the Nucleotide-Excision Repair (NER). Polymorphisms in XPD gene have been identified and reported to be associated with many types of cancer with two common single nucleotide polymorphisms (SNPs), namely, XPD312 and XPD751. The XPD312 polymorphism is at exon 10 codon 312 Asp to Asn (A→G) and the association of this polymorphism with oral cancer is very little known, especially, in Malaysia. The aim of this study was to screen for XPD312 gene polymorphisms in human oral cancer patients attending Hospital Universiti Sains Malaysia (HUSM), Malaysia. Blood samples were collected from 10 oral cancer and 10 normal healthy subjects with their consent. DNA was extracted using commercial DNA extraction kit and Polymerase Chain Reaction (PCR) was performed to amplify the XPD312 gene. The PCR products were digested using restriction enzyme, Sty I and analyzed on a 3% agarose gel for the detection of polymorphisms. This was followed by DNA sequencing to confirm the findings. In the current study, only homozygous wild type polymorphisms in the XPD312 gene was noticed in the oral cancer tissues as revealed by the restriction enzyme and DNA sequencing analyses.