Background: Oral squamous cell carcinoma (OSCC) is the most common subtype of head and neck squamous cell carcinoma (HNSC) and poses a serious threat to human health. The molecular mechanisms underlying the initiation and progression of OSCC are highly complex. Although notable advances have been made in diagnostic and therapeutic technologies in recent years, the five-year survival rate of patients has not improved substantially. Therefore, in-depth investigation of the molecular mechanisms of OSCC, identification of potential diagnostic and therapeutic biomarkers, and development of effective treatment strategies have become critical directions in current research. Aim: To investigate the relationship between the prognosis of HNSC/OSCC and the m7G-related lncRNA GSEC. Materials and Methods: RNA-seq transcriptome data and clinical data for HNSC were downloaded from The Cancer Genome Atlas (TCGA). Differential expression analysis of lncRNAs was performed, and differentially expressed lncRNAs were selected. Univariate Cox regression analysis was used to screen lncRNAs associated with prognosis. The random forest algorithm was employed to rank the importance of differentially expressed lncRNAs, and the top 50 lncRNAs were selected. Twenty-nine m7G-related genes were obtained from published literature. m7G-related lncRNAs were screened based on Pearson correlation analysis. The intersection of these results was taken to identify diagnostic biomarker m7G-related lncRNAs. The UALCAN database was used to analyze the expression of target m7G-related lncRNA in HNSC/OSCC. cBioPortal was used to analyze the gene mutation profile of GSEC in HNSC. Co-expressed genes of the target lncRNA in HNSC were collected via cBioPortal, filtering for genes with FDR<0.05 and R>0.4. GO/KEGG enrichment analysis was performed using the Metascape database. Immunohistochemical expression levels of the m7G-related gene were analyzed using the Human Protein Atlas (HPA) database. The expression level of the m7G-related lncRNA in cells was detected using qRT-PCR. Result: A total of 3,618 differentially expressed lncRNAs were identified in HNSC from the TCGA database, including 2,421 upregulated and 1,197 downregulated genes. Univariate Cox regression analysis showed that 1,306 lncRNAs were significantly associated with HNSC patient prognosis (P<0.05). The random forest algorithm ranked the top 50 important lncRNAs. Pearson correlation analysis (|correlation coefficient|>0.5, P<0.001) identified 310 m7G-related lncRNAs. Taking the intersection with lncRNAs significant in the random forest and univariate Cox regression analyses revealed that the m7G-related lncRNA GSEC has significant diagnostic value in HNSC, with DCPS identified as the m7G-related gene for lncRNA GSEC. GSEC/DCPS were significantly upregulated in HNSC/OSCC (P<0.05). High expression of GSEC showed value in predicting poor outcomes in OSCC (AUC=0.937). Analysis of the mutation spectrum of the target gene GSEC indicated that GSEC undergoes genetic mutations in HNSC, including amplification and altered mRNA expression levels. Enrichment analysis of GSEC co-expressed genes in HNSC (FDR<0.05, R>0.4) revealed that GO terms were primarily enriched in the endoplasmic reticulum lumen, glycoprotein metabolic process, and collagen fibril organization. KEGG pathways were mainly enriched in Protein processing in endoplasmic reticulum, Glycosaminoglycan biosynthesis-heparan sulfate/heparin, and Lysine degradation. Immunohistochemical analysis revealed high expression of DCPS, the m7G-related protein within the GSEC, in OSCC tissues compared to normal mucosal tissues. Further qRT-PCR detection demonstrated that GSEC is upregulated in OSCC cell lines relative to NHOK cells. Among the OSCC cell lines examined, CAL-27 exhibited the most pronounced upregulation of GSEC expression compared to SCC-4 and HSC-2 cells. Conclusion Bioinformatics analysis in this study revealed significant upregulation of the m7G-related GSEC/DCPS in HNSC/OSCC. Moreover, GSEC/DCPS expression was correlated with the prognosis of HNSC/OSCC. These findings suggest that GSEC/DCPS may serve as a novel molecular target for the diagnosis and treatment of HNSC/OSCC.

Background: Metabolic syndrome (MetS) has been shown to be associated with multiple factors, including central obesity, insulin resistance, lipid metabolism disorders, and elevated blood pressure, thereby increasing the risk of cardiovascular disease and type 2 diabetes. In recent years, the prevalence of MetS has risen sharply worldwide, affecting about one-third of the global population, becoming a major public health concern. Although several studies on MetS have been conducted in Mongolia, research investigating the relationship between iron metabolism and MetS, particularly among men who are most affected, is limited. This formed the basis for the present study. Aim: To investigate selected indicators of iron metabolism in men with and without MetS. Materials and Methods: A total of 227 men aged 30-60 years from Ulaanbaatar were included in this study. Participants were classified into two groups: MetS (case group) and non-MetS (control group). According to the British Columbia “High Ferritin and Iron Overload – Investigation and Management” (2021) guidelines, serum ferritin levels were categorized into three groups: <300 ng/mL as normal ferritin, 300–600 ng/mL as hyperferritinemia, and >600 ng/mL as iron overload. Result: The mean age of the participants was 45.3±8.3 years. Based on the 2009 JIS criteria for MetS (five components), 38.8% (n=88) had MetS and 61.2% (n=139) were without MetS. According to the British Columbia guidelines, 46.7% (n=106) had normal serum ferritin, 33.9% (n=77) had elevated ferritin, and 19.4% (n=44) had iron overload. When serum iron-related proteins were analyzed by group, the ferritin levels ranged from 33.30 to 1330.00 ng/mL with a mean of 320.34 in the non-MetS group, and from 43.10 to 1044.00 ng/mL with a mean of 378.28 in the MetS group (F=3.957, Sig=0.049), indicating a statistically significant difference in ferritin levels between the two groups. Other iron metabolism indicators, including serum iron, transferrin saturation (TSAT%), Unsaturated iron binding capacity (UIBC), Total iron binding capacity (TIBC), and hepcidin, did not show statistically significant differences between groups. Conclusion Among the indicators of iron metabolism, only serum ferritin levels showed a statistically significant difference between men with and without MetS. Other indicators did not differ significantly, highlighting the need for further detailed investigation.

Background: The cornerstone of medical education in training qualified physicians lies in foundational scientific knowledge, which forms the basis for clinical reasoning and diagnostic-therapeutic decision-making. Anatomy constitutes one of the core foundational subjects within the medical doctor training curriculum and exerts a direct influence on the development of students’ baseline knowledge and the formation of their clinical thinking. This study was conducted to evaluate the anatomy curriculum through assessments by first-year students enrolled in the basic medical education program, with the aim of enhancing instructional quality and improving the structure and organization of the course. Aim: To investigate the satisfaction ratings of first-year students in the basic medical education program regarding the Anatomy-1 course. Material and Methods: The study was carried out using an analytical cross-sectional design during the first semester of the 2025–2026 academic year. Data were collected from a total of 289 first-year students of the basic medical education program at the School of Bio-Medicine of MNUMS (Mongolian National University of Medical Sciences) using a questionnaire comprising 24 items in total—3 demographic questions, 20 general satisfaction questions, and 1 open-ended question—with each item rated on a 5-point Likert scale. Data were processed using SPSS 23.0 software, employing descriptive statistics, two-sample t-tests, ANOVA, Pearson’s correlation, and factor analysis. Results: Of the study participants, 14.2% were male and 85.8% were female, with the cohort distributed across programs as follows: TAM 10.38%, TMS 17.30%, MDS 44.29%, PDS 13.15%, and DSS 14.88%. The overall satisfaction level was 4.59±0.66, falling within the “good” range. The highest rating was attributed to “Faculty members possess strong professional knowledge and skills” (DSS, 4.91±0.37), whereas the lowest rating was assigned to “Students’ knowledge and skills are evaluated objectively and fairly” (PDS, 4.16±0.75). The internal consistency coefficient of the questionnaire yielded α=0.909, indicating excellent reliability. Correlation analysis revealed strong positive associations among instructors’ respect for students’ viewpoints (Q4), instructors’ communication and demeanor (Q5), and professional ethics (Q6) (r=0.787; r=0.755; p<0.01). Factor analysis produced a KMO value of 0.865 and a Bartlett’s test result of p=0.000; accordingly, all 20 items were grouped into two factors—”Faculty Professional Competence” and “Learning Environment and Organization”—which collectively accounted for 58.74% of the total variance. Conclusions 1. The findings indicate that the overall satisfaction of first-year basic medical education students who participated in the study was at a favorable level. 2. Faculty professional competence and the learning environment and organization were identified as factors influencing student satisfaction, explaining 58.74% of the total variance in the results. It was further established that adherence to professional ethics, respect for students’ perspectives, and equitable treatment are contingent upon the instructor’s knowledge and professional expertise.

Background: The Anatomy course, which provides general foundational knowledge on the structure of all organ systems of the human body, is a core professional course in the bachelor’s curricula of Pharmacy, Biomedical Science, Hygiene and Epidemiology, Public Health, Occupational Safety and Health, and Nutrition and Dietetics. Student satisfaction is not only an important indicator of the quality of medical education, but also influences graduates’ knowledge, skills, and attitudes; therefore, continuous research in this area is necessary. Aim: To determine the level of satisfaction with the Anatomy curriculum among first-year students in basic health science programs and to identify factors influencing their satisfaction, with the aim of improving the quality of teaching. Materials and Methods: An analytical cross-sectional study was conducted from September 2025 to February 2026 among 182 first-year students enrolled in the following programs at Mongolian National University of Medical Sciences (MNUMS): Biomedical Research, Pharmacy, Health Epidemiology, Public Health, Health Informatics, and Traditional Medicine Therapy. Student satisfaction with the quality of the Anatomy course was assessed using a 24-item questionnaire. Data were analyzed using SPSS version 26, applying descriptive statistics, independent-samples t-test, one-way analysis of variance (ANOVA), Pearson correlation, factor analysis, and multiple regression analysis. A p-value of <0.05 was considered statistically significant. Results: The internal consistency of the satisfaction scale was very high (Cronbach’s α=0.928). The mean overall satisfaction score of the participants was 4.61±0.67. There was no significant difference in overall satisfaction by gender (p > 0.05). Factor analysis identified two main factors influencing the evaluation of teaching quality (KMO=0.894; Bartlett’s test p<0.001), which together explained 52.73% of the total variance. The first factor was “Teachers’ professional competence, communication, attitude, and assessment,” and the second factor was “Course organization, learning environment, and instructional materials.” Correlation analysis showed that better course organization and higher teacher engagement were positively associated with students’ satisfaction (p<0.01). Conclusions 1. Among first-year basic health science students, satisfaction with the Anatomy course was influenced by teachers’ professional competence, ethics, interpersonal communication, and fair, objective assessment. 2. Adherence to professional ethics and maintaining respectful communication with students were found to be closely related to teachers’ knowledge and professional skills.

Background: The annual incidence of stroke in different regions of the world ranges from 100 to 336 per 100,000 pop ulation, and mortality ranges from 36 to 136, and in Mongolia there are 220 new cases of stroke per 100,000 people and 113 deaths annually, making it one of the countries with the high stroke incidence rate. Aim: To conduct a systematic review of published sources on the epidemiology, causes, and risk factors of ischemic stroke in young people. Materials and Methods: The research sources were searched using keywords such as “Stroke”, “Definition”, “Epidemi ology”, “Etiology”, “Risk factors”, “Young Adult”, “Ischemia”, “Hemorrhage”, “Silent stroke” from the works published in international platforms such as Cochrane Library, Datebase, Medline, PubMed, Google Scholar, and Web of Science, and relevant information and data were selected from the collected sources and a review article was developed. Results: According to the WHO MONICA project report, stroke incidence was reported in 16 countries, with 101–285 men and 47–198 women per 100,000 people aged 35–64 years, while in the United States it was 113.8 per 100,000 people under 55 years, of which 73.1 were cerebral infarctions per 100,000 people, and more than 10 percent were under 55 years. A recent study in Mongolia found that 21–26% of stroke patients were young people (20-50 year old), compared with 10–13% in Western countries. Among the traditional causes and risk factors for stroke in young people, arterial hypertension accounts for 45-60%, smoking 40-60%, alcoholism 40-50%, heart disease 18-30%, dyslipidemia 30%, diabetes 13%, obesity 7-36%; among the specific risk factors, migraine accounts for 10-35%, taking hormonal contraceptives 10-22%, vasculitis 6-10%, blood clotting disorders 2-10%, vascular dissection 6-40%. According to the TOAST classification, large vessel disease accounts for 16-17%, small vessel occlusion 14-15%, cardiac embolism 19-20%, other determined etiologies 22-23% and undetermined 26-27%. Conclusion Epidemiological indicators of stroke vary significantly depending on the level of development of the country, geographical characteristics of the region, lifestyle, age, and gender (stroke incidence rate range: 100–336 per 100,000 population; mortality: 36–136 per 100,000 population). Mongolia is among the countries with high rates of stroke incidence and mortality (incidence rate 220 per 100 000, mortality 113 per 100 000 population). While stroke among young people accounts for 10–13% of all cases in Western countries, this figure reaches 21–26% in Mongolia, which is explained by a combination of traditional and specific risk factors. As stroke is becoming more common among younger populations, it is essential to study its causes and risk factors in detail and to intensify efforts in diagnosis, treatment, and prevention.

Background: Currently, colorectal cancer (CRC) ranks as the third most common cancer and the second leading cause of cancer-related mortality worldwide. CRC frequently metastasizes to the liver (50%), lungs (10–15%), peritoneum (4%), bones (10.7%–23.7%), brain (0.3%–6%), and spinal cord. Approximately 35% of CRC cases are diagnosed before distant metastasis, 36% upon lymph node involvement, and 23% after distant organ metastasis. Although several studies have established primary tumor models in mice in our country, there are limited studies on experimental lung metastasis models, prompting the need for this research. Aim: To establish and evaluate a lung metastasis model of colorectal cancer in C57BL/6J mice using the MC38 cell line. Materials and Methods: This study was conducted at the Institute of Biomedical Sciences, Mongolian National University of Medical Sciences. Approval was obtained from the Ethics Review Board of the Mongolian National University of Medical Sciences (2023/3-09) and all laboratory safety regulations and protocols were strictly followed. Male C57BL/6J mice bred at the Experimental Animal Center of Mongolian National University of Medical Sciences were used. MC38 murine colorectal carcinoma cells were cultured and injected intravenously (via the tail vein) at a concentration of 0.25×10⁶ cells per mouse (n=12) to induce lung metastasis. Histological analysis was subsequently performed. Results: Histological examination revealed significant alterations in lung tissue architecture, characterized by areas of dense infiltration by pleomorphic, hyperchromatic cells, disrupting the normal alveolar structure. No histological abnormalities were observed in other organs. Conclusion Intravenous injection of MC38 colorectal adenocarcinoma cells into the tail vein of C57BL/6J mice successfully induced lung metastases, characterized by hyperchromatic, pleomorphic cell infiltrates forming glandular structures within the lung parenchyma.

Background: Studying the human embryonic and fetal organ systems development patterns and determining their quantitative indicators is of scientific and practical importance in medicine and health in every nation.
Distortions and pathologies during the development of the embryo are the causes of congenital disabilities. Among the congenital malformations, facial malformations are the 3rd place, including cleft lip and palate in 70% and Srouzon's syndrome in 30%. In addition, abnormalities due to changes in the size, shape, and position of the jaw are also mentioned in the 2021.04.21 issue of Morphology magazine in the study "Morphometric parameters of the bones of the skull and face during the development of newborns and fetuses". In our country, Ariuntuul G (2005) determined that cleft lip and cleft palate occur at 0.76/1000 or 1 in 1314 live births, while Ayanga G (2012) found that it occurs at 1 in 1072 live births or 0.93/1000. Moreover, the eye cup dimensions of Mongolian fetuses aged 16 36 weeks have a positive linear relationship with the gestational age determined using ultrasound by Nandintsetseg B (2015) et al. Compared with the other countries, the eyecup is slightly wider, and the outer edge distance is similar, whereas the inner edge distance is shorter. Purpose: To summarize research work and determine the embryonic development of bones involved in the formation of the face and facial parts, the period of bone formation, the point of ossification, and the period of formation. Methods: During fetal development, human organ systems grow and develop at different rates but in a particular relationship. This feature of growth and development is also clearly observed in the structure of the head and facial bones, and the results of researchers who have studied this aspect are selected in the articles. Results: Embryonic and fetal development of bone are clinically significant not only from the point of view of its morphogenesis but also from the point of view of congenital disabilities. Conclusion In the analysis of the sources, most of the works on the prenatal period of the development of the same body have studied the development of specific structures of the face and facial area, such as the palatine bones and nasal bones, or have generally covered the development of particular systems in the embryo and fetus, and face, there are relatively few works that show the entire dynamics of growth and development of facial bones.

Background: The aim of this study was to investigate the diameters of the bony nasolacrimal canal by computed tomography in normal adult Mongolian population and the effect of gender and age on the nasolacrimal canal diameter. Methods: Using standart tomographic images, we measured the diameters, angle between the bony canal and nasal floor and length of the bony nasolacrimal duct in 150 patients without nasolacrimal duct disease. Results: The anterioposterior diameter of the bony nasolacrimal canal was 6.49± 1.06mm, transverse diameter was 4.56±0.9mm, angle between the bony canal and nasal floor was 69.6±8.1o. No significant difference in anterioposterior diameter and transverse diameter in gender. The angle between the bony canal and nasal floor was significantly greater in male. Conclusions This study may contribute to the establishment of a detailed anatomical and morphometric baseline of the bony nasolacrimal canal and provide useful information for the planning of interventions for nasolacrimal duct obstruction

Introduction: Khuumii (throat singing) is a unique form of art derived from the nomadic population of Central Asia, producing two or more “simultaneous” sounds and melodies through the organ of speech. Material and Methods: The aim of the study is to identify the anatomical structures involved in the formation of khuumii and the features and patterns of their functions and compare each type of khuumii as performed by Mongolian people. A total of 60 participants aged 18-60 years (54 men and 6 women) were selected by non-random sampling method using cross-sectional study. Statistical analysis was performed using SPSS 23 software using questionnaires, X-ray, endoscopy, sound research method, and general blood tests. Results: 90.7% of the khuumii singers were male and 9.3% were female. The average height of the participants was 172.91±0.93 cm (arithmetic mean and mean error), average body weight was 77.53±2.46 kg, and body mass index was 25.93±5.31 respectively. Heart rate was 92.19±20.71 per minute prior to khuumii while 133.19±19.09 after performing khuumii and 85.81-98.56 at 95% confidence interval. In terms of ethnicity (ethnographically), the Khalkh were the largest ethnic group (72.1%), followed by Bayad, Buryatia, Darkhad, Torguud, and Oirat (2.3%), respectively. 60.5% of the participants were professional khuumii singers who graduated from relevant universities and colleges. The process of Khuumii was recorded by X-ray examination, and laryngeal endoscopy evaluated the movement of true and false vocal chords, interstitial volume, movements of epiglottis and arytenoid cartilage, and mucosa. Khuumii increases the workload of the cardiovascular system by 70-80%. Furthermore, the sound frequency is 2-4 times higher than that of normal speech, and sound volume is 0.5-1 times higher. 95.3% of throat singers did not have a sore throat, 88.4% did not experience heavy breathing, and 74.1% had no hoarseness. During the formation of khuumii sound, thoracic cavity, diaphragm, and lungs regulate the intensity of the air reaching the vocal folds, exert pressure on the airways and vibrate the sound waves through air flows passing through the larynx and vocal folds. Mouth-nose cavity as well as pharynx are responsible for echoing the sound. Conclusion It is appropriate to divide khuumii into two main types according to structural and functional changes in the organs involved; shakhaa and kharkhiraa. Khuumii, the “Human music” originating from the people of Altai Khangai basin by imitating the sounds of nature with their own voice in ancient times, spread all over the world from Mongolia and it is proposed to classify khuumii into two main types of shakhaa and kharkhiraa in terms of structural involvement and functionality.