Genome-wide DNA hypermethylation and homocysteine increase a risk for myopia

AIM: To test for the association between genome-wide methylation and myopia in human and mice. METHODS: Long interspersed nucleotide element 1(LINE-1) methylation levels were used to surrogate genome-wide methylation level. We first tested for the association between high myopia(<-6 D) and LINE-1 methylation in leukocytes in 220 cases and 220 control subjects. Secondly, we validated the results of LINE-1 methylation in eyes from the form deprivation myopia(FDM) mice. Furthermore,we calculated the correlation of LINE-1 methylation levels between leukocyte DNA and ocular DNA in the mice. We also tested whether dopamine can alter LINE-1 methylation levels. RESULTS: The LINE-1 methylation level was significantly higher in the myopic human subjects than controls. The upper and middle tertiles of the methylation levels increased an approximately 2-fold(P≤0.002) risk for myopia than the lower tertile. Similarly, FDM mice had high LINE-1 methylation levels in the leukocyte, retina and sclera, and furthermore the methylation levels detected from these three tissues were significantly correlated. Immunohistochemical staining revealed higher levels of homocysteine and methionine in the rodent myopic eyes than normal eyes. Dopamine treatment to the cells reduced both LINE-1 methylation and DNA methyltransferase levels. CONCLUSION: LINE-1 hypermethylation may be associated with high myopia in human and mice. Homocysteine and methionine are accumulated in myopic eyes, which may provide excess methyl group for genome-wide methylation.

Long-term rare giant sialolithiasis for 30 years:A case report and review of literature

BACKGROUND Sialolithiasis is one of the most common salivary gland disorders,most commonly affecting the submandibular gland.Submandibular sialolithiasis can be treated using non-invasive conservative measures and invasive treatments.Treatment selection was based on the ductal system anatomy and the size and location of the stones.This study aimed to review the updates on sialolithiasis treatment and compare the different management strategies of the variables.CASE SUMMARY This report presents a case of a long-term,rare,and giant sialolithiasis within the submandibular gland parenchyma for 30 years in an older adult.Our patient presented with painless right submandibular swelling.Computed tomography revealed a calcified mass measuring 35 mm×20 mm within the right submandibular gland.In this case,the infection and fibrosis of the affected gland and size of the stone did not provide us with other alternatives except for the excision of the involved gland.Thus,right submandibular sialoadenectomy was performed via the transcervical approach.After the surgery,the patient recovered without any complaints,side effects,or complications.CONCLUSION Tailored management is important for preserving gland function,maintaining low risk,and reducing patient discomfort.