No abstract

The importance of patient safety when carrying out dental and oral care processes is essential. However, the high levels of contamination that have been reported in dental units are of particular concern, so it is necessary to identify and study the patterns of bacterial contaminants and the transduction mechanisms of bacterial responses to their environment. This study investigates the diversity of bacterial contamination in dental units, chemotaxtic signals, and pathways from chemoreceptors through in silico approched. In silico research was carried out using several online and offline software tools utilizing a genomic sequence database from bacteria-contaminated with dental units. Phylogenetic analysis of the tree based on the 16s rRNA gene using MEGA 6 software, protein signaling interactions were analyzed using MiST 3.0 (https://mistdb.com/), signal transduction and protein structure (https://pfam.xfam.org/), the role of chemotaxis using interPro Ebi (https://www.ebi.ac.uk/interpro/structure/), dan biological process using Ebi QuickGo (https://www.ebi.ac.uk/QuickGO/). The analysis showed that 58 species of bacterial contamination showed a similarity test > 95%. Chemosensory pathway analysis of P. aeruginosa with a genome length of 6.538 Mbp through 8 signaling mechanism pathways for a total of 48 MCP. Signaling pathways.MCP signaling analysis classes are 24H, 36H, 40H, and 44H, while the identification of MCP classes is grouped based on chemosensory classes, namely CheW, CheA, CheR, CheB, Chev, CheD, and CheZ. The conclusion of this study, the complexity of the chemoreceptor interaction pathway in adapting quickly to the environment.

Background and Aim: Nasopharyngeal Carcinoma (NPC) is an upper respiratory tract cancer prevalent in Southeast Asia and related to chronic EBV infection. microRNAs (miRNAs) regulate gene expression implicated in NPC’s carcinogenesis . However, this circulating RNA molecule’s role and clinical utility remain unknown. Therefore, this study examined the circulation of miRNAs and their association with clinical data. Methods: 160 plasma samples of NPC and 80 non-tumor samples were extracted to evaluate and validate the gene expressions. Quantification expression was performed using relative quantification of qPCR analysis level expression methods. The intrinsic cellular roles involving biological signaling in NPC's oncogenesis using Ingenuity Pathways Analysis (IPA) were also used. Results: The results of the quantification significance profiling of NPC samples revealed decreased miR-29c-3p (fold change 1.16; p<0.05) and increased 195-5p expression (fold change 1.157; p<0.05). Furthermore, the validation of hsa-miR-29c-3p expression on plasma NPC with known tumor vs non-tumor and significant changes was also performed using a fold change of 4.45 (medians of 31.45±1.868 and 24.96±1.872, respectively; p<0.0005). miR-29c had a 2.14 fold change correlated with T primary status with a median of 31.99±1.319 and 31.35±2.412, respectively (p<0.05). Stage status with fold change 1.99 also had median levels of 31.98±1.105 and 31.21±2.355, respectively (p-value <0.05). Furthermore, the node’s status for the lower expression of miR-29c with fold change 1.17 had median levels of 32.78±2.221 and 31.33±1.689, respectively (p-value of 0.7). Bioinformatics analysis established the roles and functions of miR-29 in NPC progression, cell death and survival, cellular development, cellular function, and cell maintenance by inhibiting COL4A, PI3K, VEGFA, JUN, and CDK6. Conclusion: Overall, we conclude that decreased miR-29c expression is associated with poor clinical status and might inhibit NPC's five target genes.

Background: Radiotherapy is generally used to treat head and neck malignancy through high radiation, focusing on killing cancer cells. However, some adverse effects in oral mucosal tissue, including cell morphology changes and apoptosis, are commonly found. This study aims to determine the morphological changes and apoptosis of buccal mucosa epithelium after radiotherapy in head and neck cancer (HNC) patients.Methods: This study involved 8 subjects of patients diagnosed with HNC. Buccal mucosal smear samples were collected using cytobrush two times, before and after radiotherapy, with a dose of 70 Gy in 7 weeks. The specimens were prepared and stained using Feulgen and Rosenbeck technique. Observations were made using a light microscope with a count per 1000 epithelial cells. Statistical analysis was performed using statistical software with Pearson’s correlation test and significance t-test (p < 0.05) between irradiated and non-irradiated samples.Results: Data analysis showed significant changes in cell morphological damage and apoptosis in patients before and after radiotherapy. It increases in the number of micronuclei (p = 0.001), broken egg (p = 0.001), binuclei (p = 0.003), pyknosis (p = 0.033), karyorrhexis (p = 0.020), and karyolysis (p = 0,004). Conclusions: The effects of radiation reflect morphological changes and apoptosis in the buccal mucosa basal epithelium in HNC patients.