Background: Although breast density is an important determinant of breast cancer risk and the likelihood of masking pathological lesions on mammography, it is insufficient to fully characterize the breast imaging phenotype on its own. Age, body mass index (BMI), total body fat percentage, breast size, compressed breast thickness, tissue distribution, and reproductive history influence not only the biological composition of the breast but also the technical conditions of mammographic imaging. Aim: To synthesize the evidence on how age, BMI, body composition, breast-specific anthropometric characteristics, reproductive factors, and population-specific characteristics influence mammographic imaging. Materials and Methods: In this review, we synthesized evidence from studies indexed in PubMed/MEDLINE, Scopus, Embase, and Web of Science from 2000 through August 2026, focusing on the associations of these factors with mammographic appearance, lesion conspicuity, BI-RADS classification, image quality, radiation dose, and screening performance. Result: Breast density generally decreases with advancing age and during the menopausal transition. Increasing BMI and adipose tissue volume are also associated with lower breast tissue density. Therefore, the absolute volume of fibroglandular and connective tissue should not be inferred directly from percent breast density alone. Breast-specific parameters, particularly compressed breast thickness and breast volume, are clinically important because they influence positioning, compression, exposure parameters, and mean glandular dose. Studies in Asian cohorts have demonstrated significant associations between age, body size, and mammographic characteristics, although substantial inter-population differences have been reported. Advances in digital breast tomosynthesis (DBT) and artificial intelligence (AI) are enabling a transition from single-category breast density assessment toward multidimensional breast phenotyping. Future research should integrate DICOM technical parameters, standardized anthropometric measurements, quantitative breast density measures, and externally validated AI-derived features to improve personalized screening and radiation dose optimization. Conclusion Breast imaging phenotype should be considered a multidimensional construct integrating breast density with age, body composition, breast spatial architecture, imaging parameters, and validated AI-derived features. This approach may improve biological interpretation, radiation dose estimation, and risk stratification while avoiding the oversimplification that a single breast-density percentage or BI-RADS density category can fully characterize the breast phenotype.

Background: Conventional methods for assessing exposure to environmental tobacco smoke rely mainly on questionnaires and biomarkers with short half-lives, such as urinary cotinine. In contrast, oral mucosal pigmentation may represent a visible, non-invasive biomarker of chronic exposure. However, its clinical and policy relevance, as well as its validity for screening purposes, remain insufficiently established. Aim: To summarize the evidence on the association between exposure to environmental tobacco smoke and oral mucosal pigmentation and to assess some confounding factors. Materials and Methods: We synthesized findings from observational studies that examined the association between environmental tobacco smoke exposure and oral mucosal pigmentation across all age groups. International electronic databases, including PubMed, Embase, Web of Science, and Scopus, were searched. Data were extracted on exposure–response relationships, measurement instruments, anatomical distribution of pigmentation, confounding by physiological pigmentation, and biochemical validation. The quality of included studies was assessed using the Mixed Methods Appraisal Tool (MMAT). A narrative synthesis was conducted, focusing on the biological plausibility of the biomarker, standardization of measurement, and its potential implications for screening and tobacco control policy. Results: Thirteen observational studies from seven countries, involving a total of 3,284 participants, met the inclusion criteria. Four studies reported a statistically significant association between duration of exposure and severity of pigmentation, while one cohort study showed that urinary cotinine levels increased with age among children. The Gingival Pigmentation Index and the Dummett Oral Pigmentation Index were the most commonly used assessment tools; however, methodological heterogeneity limited direct comparability across studies. The anterior gingiva was the most frequently affected anatomical site. Only a limited number of studies adequately controlled for physiological pigmentation, and skin color was identified as an important confounding factor. The pooled odds ratio was 2.35; however, the certainty of evidence was low due to the observational nature of the included studies. Conclusion Oral mucosal pigmentation may serve as a potential biomarker of long-term exposure to environmental tobacco smoke. Nevertheless, standardized assessment protocols, adequate control for physiological pigmentation, and validation against “gold-standard” biomarkers are required. If validated, this marker could be used for rapid identification of high-risk groups and incorporated into tobacco control policies.

Background: Passive smoking among children remains a serious public health concern, particularly because children’s ability to avoid household environmental tobacco smoke exposure is limited when parents smoke. In recent years, increasing scholarly attention has been given to oral mucosal pigmentation as a potential clinical sign of long-term passive smoking in children. However, no previous study has synthesized the available evidence on this topic. Aim: This systematic review and meta-analysis aimed to evaluate the association between passive smoking and oral pigmentation in children. Materials and Methods: A systematic search was conducted in international electronic databases, including PubMed, Scopus, Web of Science, and the Cochrane Library, in accordance with PRISMA guidelines. Observational studies assessing the association between passive smoking and oral pigmentation among children aged ≤18 years were included. Methodological quality was assessed using the Mixed Methods Appraisal Tool (MMAT). A random-effects meta-analysis was performed, and pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Between-study heterogeneity was assessed using the I² statistic, and the certainty of evidence was evaluated using the GRADE approach. Results: Seven studies involving a total of 1,582 participants met the inclusion criteria. The meta-analysis demonstrated that passive smoking was significantly associated with an increased risk of oral pigmentation in children, with a pooled OR of 2.58 (95% CI, 1.35-4.95; p=0.004). Compared with children without exposure to passive smoking, those exposed to environmental tobacco smoke had an absolute risk increase of 17% (95% CI, 6.3%-23.9%). Subgroup analysis by assessment method showed a consistent effect among studies using the Gingival Pigmentation Index (GPI) (OR, 2.12; 95% CI, 1.58-2.84), whereas studies using the Dummett Oral Pigmentation Index (DOPI) showed a wider confidence interval (OR, 3.26; 95% CI, 0.68-15.54). According to the MMAT assessment, the included studies demonstrated adequate participant selection in 100% of cases, appropriate outcome measurement in 76.9%, and adequate control of confounding factors in 46.2%. Owing to the observational nature of the included studies, moderate heterogeneity, and the potential risk of confounding by physiological pigmentation, the certainty of evidence was rated as low according to GRADE. Conclusion Children exposed to environmental tobacco smoke had a significantly higher likelihood of oral mucosal pigmentation than unexposed children. These findings suggest that screening for oral mucosal pigmentation during pediatric oral examinations may serve as a non-invasive marker of passive smoking exposure and may provide visible clinical evidence to support counseling parents on smoking cessation and smoke-free household environments.

Background: Although breast cancer incidence is rising in Mongolia, little is known about how mammographic findings and BI-RADS final assessment categories are recorded in routine clinical practice. Aim: To describe report-derived finding categories and BI-RADS final assessments in a single-centre mammography registry, and to examine the association of age with BI-RADS ≥3. Materials and Methods: In this retrospective analytical cross-sectional analysis of 773 mammographic examination records, the earliest examination per participant was retained, yielding 733 women aged 20–74 years. Free-text findings were assigned to mutually exclusive categories using prespecified hierarchical keyword rules, and BI-RADS categories 3 and 4 were combined as “BI-RADS ≥3”. Group differences were examined with Pearson’s χ² test and the age association with logistic regression; a body mass index (BMI)-adjusted model was fitted in 258 women with recorded height and weight. Results: Mean age was 44.2±10.8 years. The most frequent report categories were no lesion (28.4%), calcification (20.1%), density-related descriptors (19.8%) and other benign/structural findings (16.0%). BI-RADS categories 1, 2, 3 and 4 were recorded in 312 (42.6%), 342 (46.7%), 65 (8.9%) and 14 (1.9%) women, respectively, and BI-RADS ≥3 in 79 (10.8%; 95% CI 8.7–13.2). This proportion differed across age groups (χ²=12.72; P=0.026). Each additional decade of age was associated with higher odds of BI-RADS ≥3 (OR 1.44; 95% CI 1.16–1.79; P=0.001), and the association persisted after BMI adjustment (OR 1.62; 95% CI 1.10–2.36; P=0.013). BMI was not associated with BI-RADS ≥3. Conclusions 1. Among the 733 women examined at a single hospital, the most common mammographic findings were no significant abnormalities (28.4%), calcifications (20.1%), density-related findings (19.8%), and other benign or structural changes (16.0%). 2. Of the final assessments, 89.2% were classified as BI-RADS 1–2, while 10.8% were classified as BI-RADS 3–4. No cases were classified as BI-RADS 0 or BI-RADS 5. 3. For every 10-year increase in age, the odds of receiving a BI-RADS score of ≥3 increased by a factor of 1.44. This association remained independent of body mass index (BMI).

Background: Although a considerable number of oral health studies have been conducted among children in Mongolia, most have focused on dental caries in school-aged children, and data on non-carious oral conditions in preschool children remain scarce. Aim: To determine the prevalence of oral mucosal, gingival and traumatic dental conditions among preschool children in Ulaanbaatar. Materials and Methods: In this cross-sectional pilot study, 686 children from six randomly selected kindergartens in Ulaanbaatar underwent oral examination in accordance with the World Health Organization (WHO) 2013 guidelines, using the WHO Oral Health Assessment Form for Children. The main outcomes were oral mucosal changes, including pigmentation, gingival bleeding, dental trauma and dental erosion. Analyses were restricted to the 598 children with complete records for these outcomes, and frequencies, percentages and Wilson 95% confidence intervals (CIs) were calculated using this common denominator (n=598). Results: Of the 598 children analysed, 86 (14.38%; 95% CI 11.80–17.42%) had at least one of the four main conditions. Dental erosion was observed in 74 children (12.37%; 95% CI 9.97–15.26%), confined to the enamel in 45 (7.53%) and extending into the dentine in 29 (4.85%). Oral mucosal changes were recorded in 10 children (1.67%; 95% CI 0.91–3.05%), gingival bleeding in 7 (1.17%; 95% CI 0.57–2.40%) and dental trauma in 1 (0.17%; 95% CI 0.03–0.94%), whereas oral mucosal pigmentation was observed in 64 children (10.70%; 95% CI 8.47–13.44%). Of the 86 children with findings, 85 (98.84%) attended two of the six participating kindergartens. Conclusion When dental caries was excluded, dental erosion was the most prevalent condition among preschool children, whereas oral mucosal changes, gingival bleeding and dental trauma were observed in a small proportion of children. The concentration of these findings in two of the six kindergartens may reflect local demographic and socioeconomic factors, as well as differences in examination and recording practices. Future studies should therefore standardise examination criteria in advance and include a larger number of kindergartens.

BACKGROUND. 2.3 billion Individuals have latent TB infection(LTBI), up to 10 million new cases of TB arise and killing nearly 2 million individuals around this globe, annually [1,2]. In Mongolia, tuberculinskin test is used to detection of mycobacterial infection, which has many disadvantages. Interferon gamma release assay (IGRA, QFT-G), a method advised by WHO, is the most reliable detection of latent infection. If we can detect LTBI in childhood, it is possible to prevent from active TB decreasing prevalence in the future. That is why it is important to screen the LTBI among children. GOAL: To estimate the prevalence of LTBI among 6-13 age children and to define the LTBI risk factors. Methods: We enrolled 9126 children for our study, indicating a possible estimation for LTBI prevalence among 6-13 age children in Ulaanbaatar city. Under ethical permission, our study was performed, as well as the consent of parents and children. We determined the LTBI by using QFT-G. We took a questionnaire about a socio-economic status, a history of TB contact and also conducted anthropometric measurements in all participants. The study design was a descriptive, cross-sectional and a case-control which based on QFT-G results. SPSS version 20.0.0 was used for statistical analyses. RESULTS: Regardingthe QFT-G test, 8214(90%) number of children were negative, 908 (10%) were positive, 4 (<0.1%) samples were indeterminable. There were statistically significant differences between control and case group in some questionnaire of socio-economic status. No significant difference was seen between two groups in all anthropometric measurements. In multinomial logistic regression, a tuberculosis contact, a household type, and passive smoking were identified as independent LTBI risk factors (p<0.01). CONCLUSIONS: The LTBI prevalence is high (10%) in school-age children living in Ulaanbaatar. It has increased at 6-13 age (p<0.05). Several important risk factors for LTBI in school age children elicited. Most powerful risk factors were tuberculosis contact (p<0.001), type of residence (p<0.05) and passive smoking (p<0.001).

In order to determine sleep disorders, especially insomnia due to exam stress in medical students, moreover are there any bad effects on performance of mental abilities and emotional competency, we carried out this research. We used Prospective cohort study design, involving III and IV grade 60 students, once these grades are most overloaded courses. The study performed through 2 stages: 1) Just after Final examination of a block, 2) During regular days, after sleeping well. The aim can be divided into three main categories, including evaluation of sleep disorders, estimation of brain performances and emotional competency. An average sleeping time was 3.67±1.45 hours on final exam day, whereas a main sleeping time during regular day was 7.88±1.19 hours. As totally 70% of students were estimated as having insomnia and according to insomnia severity index, 58.3% of them had subthreshold insomnia, 16.7% of them had moderate insomnia. Furthermore, regarding to Epworth sleepiness scale, 36.7% of all participants were evaluated as having mild daytime sleepiness, 13.3% had moderate, and 10% had severe sleepiness, which was more common in male students. The estimation of emotional competency consists of self-awareness, managing emotions, motivating oneself, empathy, and social skill, which were strongly associated with duration of sleep time, as well as, emotion was more stable in 4th grade students. As comparison between mental performances of sufficient and insufficient sleep time, main difference of speed 3428±1249, memory 2984±1063, attention 2472±31, flexibility 4525±1184, and problem solving 945±193 scores.

In this study we aimed to check a hypothesis about water sound (WS) effect can stimulate parasympathetic nervous system. A case-control study design was used. The students in control group did not listen WS, whereas students in case groups had been influenced under WSE by 3 different ways, including audio, video and shower. Data base had been obtained by performance of stress test, measurements of systolic and diastolic pressure, and counts of pulse. For statistical analysis, IBM SPSS 20.0 and Graphpad prism 7.0 were used. Interestingly, 92% of total students had stress. There were no differences between groups before WS effect. After WS effect, ANOVA test detected differences in diastolic pressure (ANOVA, F=6.209, p=0.001), stress score (F=15.21, p<0.001). Paired test was utilized to compare mean of values between before and post WS measurements, finding SP (p=0.001), SS (p<0.001) categories. It showed an effective WS influence. Chi-square test indicated that stress level of all students decreased significantly (p<0.001). But there were no differences between 3 methods of water therapy. In conclusion, WS has an effect of stimulation in immune system, useful for some diseases, in which parasympathetic system decrease and sympathetic system increases.

Нойр булчирхайн цочмог үрэвсэл, эмнэлзүйн урьдчилан тооцоолох дүрэм, Ranson –ийн шалгуур, APACHE II-ийн шалгуур A clinical prediction rule is a type of medical research study in which researchers try to identify the best combination of medical sign, symptoms, and other findings in predicting the probability of a specific disease or outcome. More than 80% of all patients with acute pancreatitis recover promptly without developing severe pancreatitis. The presence of early organ failure (within 24 hours of admission), multiple-organ system failure, and persistent or progressive (present beyond 48 hours after admission) organ failure are associated with prolonged hospitalization, ICU admission, need for surgery, and death. In high developed country, Ranson and APACHE II prognostic criteria are used in order to evaluate patient´s situation and modified treatment tactics. That is give an idea us to carry out retrospective study, by using patients´ documents, who hospitalized in National central hospital in last year. As result, according to Ranson´s criteria 13 (31.7%) of all patients had 0-2 score, which means mortality risk was 1.8%, 20 (48.8%) had 3-4 score (mortality risk is 11%), 8 (19.5%) were estimated 5-6 score, having 33% of mortality risk. Whereas, regarding to APACHE-II criteria 14 (34.2%) of total patients had score of 0-4, showing 4% of mortality risk, 23 (56.1%) were scored 5-9, having 8% of risk, 3 (7.3%) were scored 10-14, having 15% of risk, 1 (2.4%) had 15-19 score, having 24% of risk. Moreover, we determined that incomplete laboratory test, meaning essential prognostic criteria not used in Mongolia.