Background: Numerous studies have shown that air pollution is a serious public health threat and risk worldwide. Mongolia is the world leader in outdoor and indoor air pollution, and the morbidity and mortality caused by it are increasing every year. People spend most of their lives indoors, and it is necessary to regularly assess and study indoor air pollution. Aim: To study the concentration of PM2.5 particles in the indoor air of households in Ulaanbaatar and Darkhan cities in relation to some symptoms of respiratory diseases. Materials and Methods: The study was conducted using an analytical cohort design from October 2023 to July 2025, and the 4 districts of the central Ulaanbaatar city and Darkhan cities were included in the study. A total of 240 households were included in the study, including 48 households living in ger and house, 24 households living in apartments, and 48 households living in ger and house, and 24 households living in apartments from Ulaanbaatar city. A direct measurement device (PurpleAir) was installed in the households for 3-4 weeks to measure PM2.5 particles in the indoor air for 24 hours. After measuring PM2.5 particles in the indoor air of the household, data were collected through questionnaires from the participants aged 18-60 who participated in the study and underwent health examinations. The results were processed using STATA-19.0 and R programs. Result: 213-239 households were selected for the study, including households living in 17-26 apartments, 42-58 houses, and 38-50 houses. The 24-hour average concentration of PM2.5 particles in the ambient air of households in Ulaanbaatar city was measured relatively higher in winter and summer than in households in Darkhan city. Among the districts of Ulaanbaatar city, the highest concentration of PM2.5 particles was measured in Songinokhairkhan district, and the lowest concentration was measured in Bayanzurkh district. Considering the cities by heating type, households with stoves are more polluted than households with centralized heating. In Darkhan city, the lowest concentration was measured in apartments (22.78-31.53 μg/m³), houses (44.53-68.17 μg/m³), and the highest concentration was measured in traditional felt houses (houses) (63.20-68.25 μg/m³). In Ulaanbaatar, PM2.5 concentrations were relatively high in all types of housing, including apartments (41.61-58.37 μg/m³), houses (79.22-92.50 μg/m³), and traditional felt dwellings (76.69-86.31 μg/m³). In the summer, PM2.5 concentrations in Darkhan were 3.10-10.03 μg/m³ in apartments, 7.67-14.37 μg/m³ in houses, and 7.98-17.90 μg/m³ in traditional felt dwellings (houses). The concentration of PM2.5 particles in the ambient air of the settlement is statistically significantly associated with shortness of breath, fatigue, weakness, muscle pain, nausea, palpitations, sneezing, runny nose, conjunctivitis, pain in the eye socket, tearing of the eyes, headache, fever, nasal congestion, cough, loss of appetite, sore throat, phlegm, wheezing, and chest pain. Conclusion The 24-hour average concentration of PM2.5 particles in indoor air in households in Ulaanbaatar and Darkhan cities is higher than the Mongolian standard during winter and is statistically significantly associated with some symptoms of respiratory diseases.

Background: Stroke is the second leading cause of death and disability worldwide. According to the World Health Organization report (2018), Mongolia has one of the highest stroke rates in the Western Pacific region and ranks second globally in stroke mortality and first in stroke-related disability. However, studies investigating the prevalence of diabetes mellitus (DM) among stroke patients in Mongolia remain limited. Aim: To determine the prevalence of diabetes mellitus among patients hospitalized due to ischemic stroke and to analyse the distribution of stroke subtypes. Materials and Methods: This retrospective study included patients with ischemic stroke who were admitted to the First and Third Central Hospitals of Mongolia within 24 hours after stroke symptom onset between 2024 and 2025. Data from 292 patients were analyzed. Demographic characteristics, stroke severity, time intervals, and laboratory findings were collected and compared between patients with and without diabetes mellitus. Result: The mean age of the study population was 61.9±12.9 years, and the majority of participants were male. Diabetes mellitus was present in 25% of the patients. The median duration of diabetes was 16 years (range 0–23 years), and the mean HbA1c level was 8.81±2.46%. There were no significant differences between diabetic and non-diabetic patients in terms of age, sex distribution, stroke severity, length of hospital stay, or in-hospital mortality. However, body mass index and glycemic parameters were significantly higher in patients with diabetes (p<0.001). According to the TOAST classification, small vessel disease was the most common stroke subtype, accounting for 57.3% of cases in patients with diabetes and 44.2% in patients without diabetes. Conclusion 1. Diabetes mellitus was present in one out of every four patients hospitalized with ischemic stroke. 2. Atherosclerotic stroke was six times more frequent in patients with diabetes compared with those without diabetes, highlighting the importance of early detection and management of diabetes in stroke prevention.

Background: Ambient and household air pollution remain leading risk factors for global morbidity and mortality. Exposure to fine particulate matter (PM₂.₅) is associated with increased risks of cardiovascular and respiratory diseases, as well as lung cancer, metabolic and neurological disorders, and immune dysfunction. In urban areas of Mongolia, air pollution reaches critical levels during the winter season. Although improved solid fuels have been introduced in recent years, their impact on both outdoor and indoor air quality remains insufficiently characterized. Aim: To compare outdoor and household air pollution levels in Ulaanbaatar and Darkhan cities. Materials and Methods: Outdoor air pollution data for Ulaanbaatar were obtained from fixed monitoring stations of the National Agency for Meteorology and Environmental Monitoring for the period 2014–2026, with seasonal comparisons performed. For indoor air quality assessment, a longitudinal study was conducted among 240 households (apartments, houses, and traditional gers) in Ulaanbaatar and Darkhan from 2023 to 2026. PM₂.₅ concentrations were measured using real-time sensors (PurpleAir sensor), deployed for 14–21 days per season (winter and summer) in each household, recording data at 10-minute intervals over 24-hour periods. Result: Between 2014 and 2026, the 24-hour mean concentrations in Ulaanbaatar were 60.5 µg/m for PM₂.₅, 117.3 µg/m for PM₁₀, 37.3 µg/m for NO₂, 41.8 µg/m for SO₂, and 27.5 µg/m for O₃. While particulate matter levels showed a decreasing trend following the introduction of improved fuels, SO₂ concentrations increased, and overall pollution levels remained higher than those observed in Darkhan. Indoor PM₂.₅ concentrations were higher in Ulaanbaatar compared to Darkhan (60.7±86.1 vs 48.4±96.7 µg/m). Significant differences were observed by housing type (p<0.0001), with higher concentrations in households using solid fuels (houses and gers) and lower levels in apartments. These findings indicate substantial variability in indoor air pollution by city, housing type, and season, with persistently elevated exposure levels. Conclusion Outdoor air pollutant concentrations in Ulaanbaatar, including particulate matter, NO₂, and SO₂, exceed national standards and WHO guideline values by 1–4 times. Indoor PM₂.₅ pollution is higher in Ulaanbaatar than in Darkhan and varies significantly by housing type and season, indicating a high and heterogeneous exposure burden among urban populations.

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: The human head is an integrated biological structure composed of the brain, cranial bones, facial structures, neuromuscular systems, and sensory organs, all interconnected through coordinated signaling. The relationship between brain development, function, and craniofacial growth is most evident after birth, during which the head increases approximately fourfold in size before adulthood. Brain morphology and volume are associated not only with neurological disorders but also with cognitive and behavioral characteristics. For example, children with holoprosencephaly often present with varying degrees of facial anomalies, while studies have shown that adolescents with malocclusion exhibit higher levels of anxiety, depression, and psychological stress. With the increasing availability of magnetic resonance imaging (MRI), it has become an essential diagnostic tool in clinical practice. MRI is particularly advantageous in pediatric populations due to the absence of ionizing radiation and its superior soft tissue contrast. Recent advances in image processing techniques have enabled comprehensive analysis of both brain structures and craniofacial morphology from a single MRI dataset, forming the basis of this study. Aim: To investigate the relationship between brain tissue volumes and maxillary hypoplasia using MRI-based voxelbased morphometry in children with neurological conditions. Materials and Methods: This study was conducted at the School of Biomedicine, Mongolian National University of Medical Sciences, in collaboration with Chifeng University, as part of the project titled “Investigation of the relationship between craniofacial anomalies and brain disorders using MRI”, funded by the Ministry of Education and Science. Voxel-based morphometry (VBM) analysis was performed on brain MRI scans of children aged 9–11 years. Results: Among the 25 children included in the study, 17 (68%) were male. The youngest average age was observed in the maxillary hypoplasia group (8.4±0.95 years). The signal-to-noise ratio (SNR) of MRI was lowest in the non-temporal epilepsy group (41.1±1.35) and higher in the maxillary hypoplasia group (49.6±8.22). Both epilepsy and maxillary hypoplasia groups demonstrated physiological asymmetry of the cerebral hemispheres, with left parietal lobe dominance (−0.1% and −0.3 cm, respectively). Right frontal lobe dominance (+1.1%) was observed only in the epilepsy group. Conclusion Children aged 9–11 years with maxillary hypoplasia showed a reduction in both gray and white matter volumes of the brain. These findings highlight the importance of early diagnosis of neurodevelopmental disorders affecting odontogenesis and emphasize the need for a multidisciplinary team-based management approach.

Background: According to the World Health Organization (WHO), 99 percent of the world’s population is exposed to air that exceeds WHO recommendations, with low- and middle-income countries being the most affected. The main causes of indoor air pollution include human activities such as fuel burning, cooking, cleaning, and smoking; housing characteristics such as walls, floors, ceilings, and furniture; ventilation; and outdoor air pollution. Aim : To assess PM1 and PM10 concentrations in 120 selected households in Ulaanbaatar. Materials and Methods : Indoor PM1 and PM10 concentrations were measured using Purple Air real-time sensors in randomly selected Ulaanbaatar households between October 2023 and January 2024. Supplementary data on factors affecting the PM2.5 concentration were collected via questionnaires. Each measurement was taken in 10-minute intervals, yielding 51,309 data for analysis. Results : PM1 concentrations were measured at 55.5±53.2 μg/m³ in gers, 54.9 ± 46.7 μg/m³ in houses, and 31.6±40.1 μg//m³ in apartments (p<0.001) and measuring PM10 concentrations were 110.6±108.6 μg/m³ in gers, 110.6±96.7 μg/m³ in houses, and 62.2±83.0 μg/m³ in apartments (p<0.001) When considering the concentration of PM1, PM10 by heating type, PM1 was 55.3±50.1 μg/m³ and PM10 was 110.6±103.0 μg/m³ in households with stoves and furnaces, and PM1 was 31.6±40.1 μg/m³ and PM10 was 62.2±83.0 μg/m³ in households connected to the central heating system (p<0.001). Regarding the months of measurement, the highest concentration was observed in December 2023, at 77.1±94.1 μg/m³. The highest concentrations for both PM₁ and PM₁₀ were recorded in January 2024, at PM₁: 64.8±55.1 μg/m³, PM₁₀: 131.4±116.0 μg/m³. Conclusion 1. Indoor PM10 concentrations in residential environments in Ulaanbaatar city were within the MNS4585:2016 Air Quality Standard, however, it was exceeded the WHO air quality guidelines, indicating an excessive risk of increasing morbidity and mortality among the population. 2. Indoor PM1 and PM10 concentrations in residential environments in Ulaanbaatar varies depending on location, type of housing, type of heating, and month of measurement.

Background: A 2018 study on the global burden of disease, accidents, and risk factors reported that 1.6 million peo ple died in 2017 due to household air pollution. Poor indoor air quality has been highlighted as a contributing factor to respiratory diseases, cardiovascular conditions, and exacerbation of asthma and allergies. A 2019 study estimated that long-term exposure to fine particulate matter (PM2.5) with a diameter of 2.5 micrometers or less reduces average life expectancy by 1.8 years, with more severe effects in highly polluted regions. Additionally, a study by Miller et al. (2007) found that prolonged exposure to PM2.5 increases the risk of cardiovascular diseases, particularly among women. Direct measurement devices are highly effective in determining indoor PM2.5 concentrations, identifying sources of pollution, tracking pollutant dispersion, and monitoring temporal variations. Studies suggest that direct measurement is an accurate, cost-effective method that provides detailed data suitable for local conditions. Aim: To investigate the indoor air quality of houses and apartments in Darkhan city during the winter season using the Purple Air monitoring device. Materials and Methods: A cross-sectional study was conducted with a targeted sample of 128 households in Darkhan city. The study examined factors such as stove type, type of coal used, annual and daily coal consumption, frequency of heating, and chimney sealing conditions. To collect data, the Purple Air monitoring device was installed in each house hold for a month, after which it was retrieved. During retrieval, participants completed a questionnaire. The questionnaire consisted of 55 questions across 7 pages at the time of device installation and 25 questions across 3 pages at the time of device retrieval. The collected data was analyzed using SPSS 25.0. Results: A total of 128 households in Darkhan city participated in the study. The average duration of residence in the current home was 9.5 years, with no statistically significant variation. The distribution of housing types was as follows: traditional Mongolian gers (40.6%), houses (39.1%), and apartments (20.3%). The 24-hour average PM2.5 concentration was highest in gers (70.9 μg/m³), followed by houses (46.8 μg/m³) and apartments (22.8 μg/m³), with a statistically significant difference (p=0.0001). PM2.5 levels were most variable in gers, followed by houses and then apartments. House holds using central heating (apartments) had an average 24-hour PM2.5 concentration of 22.8 μg/m³, whereas households using stoves (gers and houses) had a significantly higher concentration of 59.4 μg/m³ (p=0.0001). However, there was no statistically significant difference between traditional and improved stoves. Among study participants, 21.4% reported that someone in their household smoked indoors. Additionally, 86.5% regularly burned incense, candles, or herbs, while 99.2% did not use an air purifier. Conclusion The indoor particulate matter concentration in houses and gers in Darkhan was 59.4μг/m3. Variations in stove types, poor chimney sealing limited space, and frequent gaps and cracks contribute to increased spread of indoor air pollutants.

Background: Cervical cancer is a common disease among women. Treatment for cervical cancer includes surgery, radiation therapy, chemotherapy, or a combination of chemotherapy and radiation therapy. Cisplatin is the first-line chemotherapy drug for cervical cancer. Research has shown that about 20% of cervical cancer patients become resistant to chemotherapy, which results in decreased results, tumor recurrence, and poor prognosis. Therefore, researching new drugs, improving the sensitivity of cervical cancer cells to cisplatin, and improving the effectiveness of cervical cancer treatment is the basis of this research. Aim: To investigate the inhibitory effect of curcumin on cisplatin-resistant cervical cancer Hela/DDP and SiHa/DDP cell lines. Materials and Methods: The study utilized cisplatin-resistant cervical squamous carcinoma (SiHa/DDP) and adenocarcinoma (Hela/DDP) cell lines. The cells in the experimental group were treated with 8.5 μM of curcumin, while the control group received only the culture medium. A colony formation assay was conducted to assess cell proliferation, with colonies stained using crystal violet; the number of colonies was then counted and compared between the two groups. Results : 1. In the Hela/DDP cell line, the control group formed an average of 507.7±15.70 colonies, whereas the experimental group, treated with curcumin, formed 112.3±16.17 colonies. The difference between the groups was statistically significant (p < 0.0001). 2. In the SiHa/DDP cell line, the control group had an average of 450.3±17.95 colonies, while the experimental group treated with curcumin had 198.3±13.05 colonies. This difference was also statistically significant (p < 0.0001). Conclusions 1. Curcumin significantly reduces the proliferation of cisplatin-resistant cervical squamous cell carcinoma (Hela/DDP) cells. 2. Curcumin significantly reduces the proliferation of cisplatin-resistant cervical adenocarcinoma (SiHa/DDP) cells.

Background: According to the World Health Organization (WHO), air pollution was responsible for 8.1 million deaths globally in 2021, making it the second leading cause of death, including among children under 5 years old. Air pollution is also linked to a range of diseases such as stroke, chronic obstructive pulmonary disease, lung cancer, and asthma. In Ulaanbaatar, the capital of Mongolia, the average daily concentration of PM2.5 particles in the air reaches 750 μg/m3 during winter, which is 50 times higher than the WHO’s recommendation, making it one of the most polluted cities in the world. Air pollution continues to pose a significant public health challenge not only in Mongolia but also in many countries globally. However, there is a lack of comprehensive research and studies that summarize and review the existing work in this field. Aim: To summarize and review thematic works on air pollution conducted by researchers from Mongolian universities. Materials and Methods: A systematic review and analysis were performed on thematic works by researchers who completed their master’s and doctoral degrees in the field of air pollution between 2011 and 2024. Results: In terms of the type of master’s and doctoral dissertations, 76.0% (n=19) were master’s theses and 24.0% (n=6) were doctoral dissertations. Among the total number of works included in the study, 36.0% (n=9) focused on the health effects of air pollution, while 64.0% (n=16) addressed other related areas. Some studies indicated that PM2.5 levels in the air between 2011 and 2024 were 1-6 times higher than the Mongolian standard, with the highest levels observed from November to February and the lowest in July. Additionally, some studies suggested a reduction in PM2.5 levels following the introduction of improved fuel in Ulaanbaatar. Air pollution was found to increase the risk of respiratory and cardiovascular diseases, as well as cancer, and to contribute to reduced fetal weight. Conclusion When examining thematic studies on air pollution conducted by state-owned universities in Mongolia, the primary focus has been on the composition, concentration, and health impacts of air pollution. Going forward, research aimed at mitigating air pollution should be driven by collaborative efforts and leadership from universities, with the results being effectively communicated to policymakers.