ABSTRACT
Background:The double strand break repair pathway, comprising XRCC2 and XRCC3 has crucial role in maintenance of genomic stability and prevention of tumor initiation and progression. Therefore, sequence variants of such DNA repair genes may compromise individual's DNA repair capacity and can influence risk of developing breast cancer. Method and Results:To estimate the impending effect of XRCC2 (Arg188His) and XRCC3 (Thr241Met) polymorphisms on breast cancer, 133 breast cancer patients and 154 healthy controls were evaluated by PCR-RFLP method. In the present study, it was noted that there was no significant correlation between these polymorphisms and breast cancer risk. However, within patient group, significant association of XRCC2 variants with PR negative breast cancer was detected. Further, patients with XRCC2 variant genotypes were also at high risk of developing TNBC and Her2 enriched subtypes as compared to luminal A subtype. Significant relation was also obtained between XRCC3 variants and large sized and infiltrative breast tumors. Conclusion: These noteworthy observations demonstrate potential involvement of XRCC2 and XRCC3 polymorphisms in pathophysiology of breast cancer.
ABSTRACT
Background: Malocclusion in the vertical and sagittal planes is easy to observe whereas it is difficult to diagnose malocclusion in the transverse plane. There are yet no criteria defining a normal transverse occlusion. Aim: The aim of this study was to identify a ratio that defines a normal transverse occlusion. Study Design: This was a retrospective study. Materials and Methods: A total sample of 151 maxillary dental models (M = 55, F = 96) in the age range of 12-16 years were randomly selected, with 73 models in control group and 78 in the study group. All the models were mixed up and given to an operator for the measurement of intercanine width (ICW) and inter-palatal molar width (IPMW). Statistical Analysis Used : The data were statistically analyzed using SPSS software version 16.0. Chi-square test was performed to test the statistical significance difference between the groups at p ≤ 0.05. Results: Nearly 98.60% of normal arches were found to have an IPMW to ICW ratio of 1:1 ± 0.05. On further analysis, it was found that when IPMW ≥37.45 mm, then the case may be considered to have normal arches, and if the ratio between IPMW to ICW is 1.15:1 ± 0.05 or more and IPMW is <34.92 mm, then the case may be identified as deficient arch. Conclusion : The IPMW-to-ICW ratio can be used to differentiate deficient and normal arches. This hypothesis (Banker's hypothesis) is an easy and noninvasive method, using only two parameters, developed to help clinicians in identifying normal transverse dimension.