The complex microbiome of caries-active and caries-free supragingival plaques in permanent dentition.

BACKGROUND AND AIM: Dental caries is one of the most common diseases seen in the oral cavity in all periods of deciduous, mixed, and permanent dentition. A comprehensive study of the oral microbiome is required to understand its polymicrobial etiology. The aim of this study was to reveal the plaque microbiome of caries-active and caries-free adults. MATERIALS AND METHODS: A total of 52 samples were collected from 26 caries-active patients and 26 caries-free controls. Dental supragingival plaque samples were collected from each subject and the bacterial 16S rDNA, expanded V3-V4 region, was amplified using next generation sequencing. RESULTS: The core microbiome was defined with 235 shared bacteria in genus level, and among all microbiome 14.8% of all bacteria showed significant difference (P < 0.05). The bacteria responsible of caries may be listed as Anaeroglobus, Atopobium, Bifidobacterium, Centipeda, Cryptobacterium, Desulfobulbus, Filifactor, Howardella, Lactobacillus, Leptotrichiaceae (unclassified), Megasphaera, Mycoplasma, Olsenella, Phocaeicola, Propionibacterium, Pseudoramibacter, Scardovia, Schwartzia, Treponema, and Veillonellaceae (unclassified). CONCLUSION: The present study provides comprehensive knowledge of the microbiological etiology of caries in permanent dentition.

Endothelial function and endothelial nitric oxide synthase intron 4a/b polymorphism in primary hyperparathyroidism.

BACKGROUND AND AIM: Patients with symptomatic primary hyperparathyroidism (pHT) have increased cardiovascular morbidity and mortality. Endothelial nitric oxide synthase (eNOS) intron 4a/b polymorphism is associated with coronary artery disease and hypertension in various populations. Our aim is to evaluate endothelial function in patients with pHT during pre-operative hypercalcemic and post-operative normocalcemic periods and to determine whether intron 4a/b polymorphism of eNOS gene influences endothelial function. SUBJECTS AND METHODS: Forty patients with pHT (age 48.48+/-11.64 yr) were examined pre-operatively and reexamined 5.8+/-1.9 months after parathyroidectomy. Forty-three healthy subjects (age 47.13+/-8.14 yr) were served as control group. Endothelial function was determined by flow-mediated dilation of brachial artery (FMD). eNOS4a/b polymorphism was detected by polymerase chain reaction. RESULTS: FMD was significantly lower in patients pre-operatively compared with controls (8.48+/-1.78% vs 19.49+/-2.34%, p<0.001). FMD improved significantly after parathyroidectomy (16.19+/-2.16%, p<0.001 compared with pre-operative measurements), but was still significantly lower than controls (p<0.001). The distribution of eNOS4a/b genotype frequencies was not significantly different between patients and controls. Logistic regression analysis showed that increased serum calcium (>2.47 mmol/l) and PTH concentrations (>7.75 pmol/l) were significant independent predictors of lower FMD (<16.7%). ENOS4a/b polymorphism did not enter in this model. CONCLUSION: Impaired endothelial function in patients with pHT improves after successful parathyroid surgery. No compelling data are evident to suggest that eNOS4a/b polymorphism modifies the endothelial function in patients with pHT.

MEFV gene 3'-UTR Alu repeat polymorphisms in patients with familial Mediterranean fever.

OBJECTIVE: Familial Mediterranean fever (FMF), an autosomal recessively inherited autoinflammatory disorder, is caused by missense mutations in the pyrin-encoding MEFV gene. The MEFV mutations can be detected in the majority of FMF patients, but there is an important proportion of patients with the FMF phenotype who carry a single or no coding region mutation. This study aimed to investigate the promoter region and 3'-UTR polymorphisms of the MEFV gene in a group of FMF patients with no coding region mutations, to identify variations with a possible role in the regulation of MEFV expression. METHODS: The study group consisted of 289 patients with FMF and 103 ethnically-matched healthy individuals of Turkish origin. All individuals were first genotyped for the five most commonly observed mutations (M694V, M680I, V726A, E148Q and M694I). Then, the coding regions of the MEFV gene in patients carrying none of the 5 mutations were amplified and screened using single-stranded conformation polymorphism and DNA sequencing. After the exclusion of patients with mutations in exons, the promoter and 3'-UTR regions of the MEFV gene were investigated in the remainder. For the haplotype analysis, all study groups were genotyped for two of the 3'-UTR single nucleotide polymorphisms (SNP). RESULTS: Genotyping for five mutations revealed 186 patients (64.4%) with two mutations, 61 patients (21.1%) with one mutation, and 42 patients (14.5%) with no mutation. The carrier rate for healthy controls was found to be 10%. After screening all 10 exons in the patients with none of the 5 mutations, we identified 36 patients (12.5%) who had no coding region mutations. Analysis of the 3'-UTR region in these patients showed two Alu repeats (AluSx and AluSq), which were located in the 3'-UTR of the reference mRNA sequence. Sequencing of the 3'-UTR of the MEFV gene showed several SNPs that were clustered in 2 haplotypes. When we genotyped all study groups for two of the 3'-UTR SNPs (rs2741918 and rs450021), we observed a significant increase in the frequency of heterozygotes for the 3'-UTR haplotypes in the FMF patients with no coding region polymorphisms compared to the healthy controls (75% versus 48.5%, p=0.006, OR=3.2, 95% CI 1.4-7.4). CONCLUSION: This study showed a group of 3'-UTR polymorphisms in the MEFV gene that are clustered in two haplotypes. In addition, a genetic association was observed between 3'-UTR polymorphisms and the FMF patients with no coding region mutations. These findings may suggest a role for 3'-UTR sequences in the regulation of MEFV expression.

The presence of erythropoietin receptor in parathyroid cells.

CONTEXT: Effects of erythropoietin on parathyroid cell function has not been studied before. OBJECTIVE: We aimed to demonstrate whether erythropoietin receptor present in parathyroid cells. DESIGN: The specimens of normal parathyroid gland, parathyroid adenoma and hyperplasia were retrieved from our pathology archives. The sections were stained immunohistochemically. Quantitative gene expression study was performed for erythropoietin and erythropoietin receptor. RESULTS: Erythropoietin receptors were detected by immunohistochemical staining and by its gene expression. Its density was higher in normal parathyroid, followed by parathyroid adenoma and hyperplasia. CONCLUSION: Erythropoietin receptor is present in normal parathyroid, parathyroid adenoma, and hyperplasia.

Clinical characteristics and genetic screening of an extended family with MEN2A.

MEN-2A is characterized by medullary thyroid carcinoma (MTC) with pheochromocytoma and sometimes parathyroid adenoma. In affected members of the family, the risk of MTC is about 100%. Biochemical screening allows tumors to be detected early but even at this stage treatment is not always curative. Missense mutations in exon 10 and 11 of the RET proto-oncogene are associated with MEN-2A. Early detection of this mutation by DNA analysis allows the identification of the carriers of the gene. We performed genetic screening in 88 members of an extended family with MEN-2A and found 18 members positive for RET mutation (Cys634Gly). Only three of these 18 RET positive cases had a previous diagnosis of medullary cancer and/or pheochromocytoma. Up to now, 12 of the RET positive cases have undergone thyroidectomy. There was extended disease with cervical lymph node metastasis in 6 of them, bilateral medullary microcancer in 3 and c-cell hyperplasia in the remaining 3. Three of the 18 RET positive patients had also pheochromocytoma. Primary hyperparathyroidism was present in only one patient. The mean age of diagnosis of medullary cancer was between 25-50 yr and mean age of death was between 35-95 yr in affected members of the family. The family had many other affected members in other cities in Turkey and in other countries throughout the world from Australia to the Netherlands. So this family is perhaps one of the most extended families with MEN-2A.