Human Translesion Synthesis Polymerases polκ and polη Perform Error-Free Replication across N2-dG Methyleugenol and Estragole DNA Adducts.

The secondary metabolites of polypropanoids, methyleugenol (MEG), and estragole (EG), found in many herbs and spices, are commonly used as food flavoring agents and as ingredients in cosmetics. MEG and EG have been reported to cause hepatocarcinogenicity in rodents, human livers, and lung cells. The formation of N2-dG and N6-dA DNA adducts is primarily attributed to the carcinogenicity of these compounds. Therefore, these compounds have been classified as "possible human carcinogens" by the International Agency for Research on Cancer and "reasonably anticipated to be a human carcinogen" by the National Toxicology Program. Herein, we report the synthesis of the N2-MEG-dG and N2-EG-dG modified oligonucleotides to study the mutagenicity of these DNA adducts. Our studies show that N2-MEG-dG and N2-EG-dG could be bypassed by human translesion synthesis (TLS) polymerases hpolκ and hpolη in an error-free manner. The steady-state kinetics of dCTP incorporation by hpolκ across N2-MEG-dG and N2-EG-dG adducts show that the catalytic efficiencies (kcat/Km) were ∼2.5- and ∼4.4-fold higher, respectively, compared to the unmodified dG template. A full-length primer extension assay demonstrates that hpolκ exhibits better catalytic efficiency than hpolη. Molecular modeling and dynamics studies capturing pre-insertion, insertion, and post-insertion steps reveal the structural features associated with the efficient bypass of the N2-MEG-dG adduct by hpolκ and indicate the reorientation of the adduct in the active site allowing the successful insertion of the incoming nucleotide. Together, these results suggest that though hpolκ and hpolη perform error-free TLS across MEG and EG during DNA replication, the observed carcinogenicity of these adducts could be attributed to the involvement of other low fidelity polymerases.

Prevalence of Traumatic Dental Injuries among 1- to 14-year-old Children: A Retrospective Study.

AIM AND OBJECTIVE: To evaluate the prevalence of dental trauma in children in the age-group of 1 to 14 years in New Delhi. MATERIALS AND METHODS: This is a retrospective study conducted from March 2017 to December 2017. A total of 6,765 children between 1 years and 14 years of age, who reported in OPD were evaluated for age, gender, type of trauma, and involvement of soft tissue. RESULTS: The mean age of participating children was 9.98 ± 1.704 and trauma was present in 1.25% of children. Ellis class IV type of trauma was seen in maximum (36.5%) cases with maxillary central incisors being most frequently injured during dental trauma. CONCLUSION: The present retrospective study surveys traumatic dental injuries which are frequently seen. The knowledge of the prevalence and etiology of trauma to anterior teeth is necessary to identify the risk groups, treatment requirements, and strengthening of preventive programs. HOW TO CITE THIS ARTICLE: Goswami M, Aggarwal T. Prevalence of Traumatic Dental Injuries among 1- to 14-year-old Children: A Retrospective Study. Int J Clin Pediatr Dent 2021;14(4):467-470.

Assessment of Oral Health Educational Program on oral health status of visually impaired children in New Delhi.

AIM: The present study was conducted with the aim to assess the effectiveness of Oral Health Education programme on Oral Health Status of visually impaired children in New Delhi. A specially designed oral health educational programme consisting of audio aid, Braille booklet and individualized training was implemented to educate and motivate visually impaired children for maintaining their oral health. METHODS AND RESULTS: A total sample size of 120 children in the age group of 5-15 years was selected and questionnaire based on WHO criteria 2013 was administrated. In oral examination caries status using DMFT/S and dmft/s and oral hygiene status using plaque index given by Sillness and Loe was evaluated at the baseline and re-evaluated after nine months. Oral Health Educational Programme was implemented and reinforced every month for nine months. Results showed that at the end of nine months 55.04% children started brushing twice daily as compared to 30% children at baseline. There was a statiscally significant decrease (0.1887±0.332) in plaque index scores at the end of nine months. CONCLUSION: It was concluded that Oral Health Educational Programme was effective in improving the oral hygiene status among visually impaired children.

Pleomorphic rhabdomyosarcoma of the left atrium mimicking myxoma.

Primary rhabdomyosarcoma (RMS) of the heart is a rare malignant tumor which has poor prognosis and survival despite surgery and adjuvant chemotherapy. The preoperative diagnosis is often difficult in view of nonspecific clinicoradiological findings. This report describes a case of a 60-year-old woman who was clinically diagnosed as left atrial myxoma. A diagnosis of pleomorphic RMS was made on histopathology after excision. Our case discusses the clinicopathological features and treatment options of cardiac RMS emphasizing the fact that histopathology and immunohistochemistry are essential to confirm the diagnosis of such an aggressive malignant tumor.