Megalin Expression in Primary Oral Squamous Cell Carcinoma Is Associated with the Presence of Lymph Node Metastases, Vascular Invasion, and Lower Overall Survival

Megalin (LRP2) is a rapidly recycling multiligand endocytic receptor primarily expressed in polarized epithelial cells. Although megalin might be involved in tumor growth and invasiveness through several mechanisms, its role has been understudied in the field of molecular oncology so far. The present study aimed to evaluate the impact of megalin expression in oral squamous cell carcinoma (OSCC) on disease progression. Megalin expression was evaluated immunohistochemically in 63 OSCC specimens. Data obtained were retrospectively compared with patient clinicopathological features and their survival. The proportion of megalin-expressing cells in the primary OSCC tissue was significantly associated with metastatic spreading to lymph nodes, vascular invasion and lower overall survival rate. Results obtained by the study suggest that megalin can be considered as a novel molecule involved in OSCC pathogenesis, but also useful as a potential biomarker for cancer progression.

On Approximating the pIC50 Value of COVID-19 Medicines In Silico with Artificial Neural Networks

In the case of pandemics such as COVID-19, the rapid development of medicines addressing the symptoms is necessary to alleviate the pressure on the medical system. One of the key steps in medicine evaluation is the determination of pIC50 factor, which is a negative logarithmic expression of the half maximal inhibitory concentration (IC50). Determining this value can be a lengthy and complicated process. A tool allowing for a quick approximation of pIC50 based on the molecular makeup of medicine could be valuable. In this paper, the creation of the artificial intelligence (AI)-based model is performed using a publicly available dataset of molecules and their pIC50 values. The modeling algorithms used are artificial and convolutional neural networks (ANN and CNN). Three approaches are tested-modeling using just molecular properties (MP), encoded SMILES representation of the molecule, and the combination of both input types. Models are evaluated using the coefficient of determination (R2) and mean absolute percentage error (MAPE) in a five-fold cross-validation scheme to assure the validity of the results. The obtained models show that the highest quality regression (R2¯=0.99, σR2¯=0.001; MAPE¯=0.009%, σMAPE¯=0.009), by a large margin, is obtained when using a hybrid neural network trained with both MP and SMILES.

Self-Massage and Low-Level Laser in Treatment of Masseter Myalgia: Short-Term Effect

INTRODUCTION

The aim of this study was to explore the efficiency of massage in the treatment of masseter myalgia compared with biostimulatory laser.

MATERIALS AND METHODS

The instrument Diagnostic Criteria for Temporomandibular Disorders was used to select subjects and monitor treatment outcome. 54 subjects with masseter myalgia of more than 3 months in duration were invited to participated and 42 cases were available at the end and analyzed. Age range was 16-67 years (median 33, interquartile range 25-53), 36% subjects was ≥40 years and there were 62% females in both groups. Both treatment groups (self-massage and laser) had 21 participants and were monitored one months after the start of treatment. Age, gender, distress, somatization, catastrophizing, hypervigilance, health competence and oral parafunctions were also assessed as factors that could influence effectiveness of treatment.

RESULTS

Laser and massage are effective in reducing symptoms of chronic myalgia of the masseter in self-reported limitation of jaw function and reducing pain intensities (p<0.001). Increase of mouth opening was present in both groups, but mainly significant in laser group. The differences in the amount of change between groups were not significant. Psychological characteristics and parafunctions, present before the treatment, age and gender did not have major affect the effectiveness of treatment.

CONCLUSION

Both treatment modalities are effective in treatment of chronic myalgia in short-term.

Environmental geology and hydrology

Environmental geology is scientific discipline dealing with the interactions between humans and the geologic environment. Many natural hazards, which have great impact on humans and their environment, are caused by geological settings. On the other hand, human activities have great impact on the physical environment, especially in the last decades due to dramatic human population growth. Natural disasters often hit densely populated areas causing tremendous death toll and material damage. Demand for resources enhanced remarkably, as well as waste production. Exploitation of mineral resources deteriorate huge areas of land, produce enormous mine waste and pollute soil, water and air. Environmental geology is a broad discipline and only selected themes will be presented in the following subchapters: (1) floods as natural hazard, (2) water as geological resource and (3) the mining and mineral processing as types of human activities dealing with geological materials that affect the environment and human health.

The role of P2X3 receptors in bilateral masseter muscle allodynia in rats

AIM

To determine the relationship between bilateral allodynia induced by masseter inflammation and P2X3 receptor expression changes in trigeminal ganglia (TRG) and the influence of intramasseteric P2X3 antagonist administration on bilateral masseter allodynia.

METHODS

To induce bilateral allodynia, rats received a unilateral injection of complete Freund's adjuvant (CFA) into the masseter muscle. Bilateral head withdrawal threshold (HWT) was measured 4 days later. Behavioral measurements were followed by bilateral masseter muscle and TRG dissection. Masseter tissue was evaluated histopathologically and TRG tissue was analyzed for P2X3 receptor mRNA expression by using quantitative real-time polymerase chain reaction (PCR) analysis. To assess the P2X3 receptor involvement in nocifensive behavior, two doses (6 and 60 μg/50 μL) of selective P2X3 antagonist A-317491 were administrated into the inflamed masseter muscle 4 days after the CFA injection. Bilateral HWT was measured at 15-, 30-, 60-, and 120-minute time points.

RESULTS

HWT was bilaterally reduced after the CFA injection (P<0.001). Intramasseteric inflammation was confirmed ipsilaterally to the CFA injection. Quantitative real-time PCR analysis demonstrated enhanced P2X3 expression in TRG ipsilaterally to CFA administration (P<0.01). In comparison with controls, the dose of 6 μg of A-317491 significantly increased bilateral HWT at 15-, 30-, and 60-minute time points after the A-317491 administration (P<0.001), whereas the dose of 60 μg of A-317491 was efficient at all time points ipsilaterally (P=0.004) and at 15-, 30-, and 60-minute time points contralaterally (P<0.001).

CONCLUSION

Unilateral masseter inflammation can induce bilateral allodynia in rats. The study provided evidence that P2X3 receptors can functionally influence masseter muscle allodynia and suggested that P2X3 receptors expressed in TRG neurons are involved in masseter inflammatory pain conditions.

The effect of frequent removable partial denture wearing on alveolar bone resorption

AIM

To determine the influence of frequent removable partial denture (RPD) wearing on the alveolar bone density changes around the abutment teeth.

METHODS

Fifty examinees of both genders, wearing partial dentures, were included in the study. Thirty one of the examinees (62%) were wearing the dentures 24 hours a day, while nineteen (34%) of them were wearing them only during the day. The changes in the bone density around the abutment teeth were determined by the intraoral microdensitometry method. Standard retroalveolar radiographs were performed twice. The first one before the removable partial denture delivery and the second one after a period of three-month denture wearing. A copper step wedge consisting of five steps (0.1-0.5 mm) was attached to the radiograph in order to calibrate it. Seven points, regions of interest (ROI) close to the root of the abutment tooth, all ten pixels in size, were selected on each radiograph. Grey areas in the regions of interest were measured and converted into the copper step wedge thickness equivalents in order to estimate the change in the alveolar bone density and measure the difference in alveolar bone density between two radiographs.

RESULTS

The results indicated that there is not any statistically relevant change (t-value less than 2,011; t(49,0.05) / F less than 4,0426; F0.05(1,48)) in the alveolar bone density depending on the frequency of removable partial denture wearing.

CONCLUSION

The frequency of removable partial denture wearing does not cause any changes in the alveolar bone density around the abutment teeth in the period of three-month denture wearing.

Influences of age and maxillary anterior teeth status on patient's satisfaction with dental appearance and tooth colour

OBJECTIVES

To study the impact of age, gender, tooth colour and maxillary anterior teeth status on patient's satisfaction with their dental appearance.

MATERIAL AND METHODS

A total of 259 Caucasian subjects participated in the study (119 men, mean age 56 years; 140 women, mean age 61 years) divided into three age groups (young <35 age; middle aged 35-54 age; old ≥55 age). Their maxillary anterior teeth status was classified into three groups: (1) natural teeth (NTG) group; (2) composite filling group (CFG) and (3) porcelain-fused-to-metal fixed prosthodontic restoration group (FPDG). The participants judged appearance and tooth colour using a scale with three categories: completely dissatisfied, moderately dissatisfied and completely satisfied.

RESULTS

Almost half of the participants were completely satisfied with their dental appearance and tooth colour. Half of the 'young' and 'middle-aged' participants with natural maxillary anterior teeth were completely satisfied and half of the 'old' participants were moderately satisfied with their dental appearance and tooth colour. The majority of participants with composite restorations (45-51%) were moderately satisfied with their dental appearance, one-third of 'young' and 'middle-aged' participants were moderately satisfied or dissatisfied with their tooth colour and more than 70% of older participants were dissatisfied with their tooth colour (p > 0.05).

CONCLUSIONS

Satisfaction with the appearance of the maxillary anterior teeth differed both between individuals of different age and different dental status.