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: Type I hypersensitivity, commonly known as an allergic reaction, is characterised by an IgE-mediated immune response triggered when foreign proteins enter the body. During allergic reactions, cytokines such as IL-4, IL-5, IL-9, and IL-13, secreted by T-helper 2 (Th2) cells, play a crucial role in activating immune effector cells like eosinophils and mast cells, which contribute significantly to airway inflammation and obstruction. Conversely, interferon-gamma (IFN-γ), produced by Th1 cells, suppresses Th2-mediated responses and plays an essential role in regulating allergic inflammation. Therefore, determining the balance of cytokines produced by Th1 and Th2 cells is crucial for understanding the mechanisms underlying allergic responses. Aim: We aimed to induce an allergic response in experimental animals using ovalbumin and to determine the levels of IL-4 and IFN-γ cytokines using an in-house enzyme-linked immunosorbent assay (ELISA). Materials and Methods: A total of 20 female C57BL/6 mice aged 6–8 weeks were selected for the experiment and randomly divided into two groups: control and experimental groups. The concentrations of IL-4 and IFN-γ cytokines in mouse serum were determined using an in-house enzyme-linked immunosorbent assay (ELISA). Result: Compared to the control group, the levels of IL-4 and IFN-γ cytokines in the serum of allergic model-induced C57BL/6 mice were determined to be 513.7 pg/mL and 193.2 pg/mL, respectively. A statistically significant difference was observed in IL-4 cytokine levels between the two groups (p < 0.001). Conclusion In the allergic model group, serum levels of IL-4 cytokine were elevated, while IFN-γ cytokine levels were decreased, suggesting a predominant Th2-type immune response.

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: 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: To effectively deliver healthcare services, it is necessary to strengthen and expand the education system for qualified biomedical equipment technicians and engineers. This should be combined with measures such as providing modern equipment to health facilities and making spare parts available. Internationally, there is a reference of one engineer responsible for 100 pieces of equipment. Additionally, one engineer is responsible for each major piece of equipment such as MRI, CT, positron emission tomography (PET SCAN), and angiography equipment. However, in our country, the standard is independent of the number of medical equipment. Although 4 universities nationwide train medical equipment engineers and technicians, they are unable to meet the growing market needs. Aim: To assess human resource needs for biomedical equipment specialists. Materials and Methods: We conducted the study using an analytical survey design. In the study, data were collected from a total of 272 engineers and technicians using a self-administered questionnaire that included years of work experience, post-graduate training, qualification level, and workload. The data were processed using SPSS Statistics 26 software, and the results were presented in figures, tables, and sentences. Results: Of the professionals surveyed, 72.4% were male, 95.6% were full-time employees, and 68.8% had a bachelor’s degree. However, the majority (90.4%) of the professionals did not have a professional degree. When asked about the availability of on-the-job and other training among the professionals 73.5% had not received any training at all. The level of training received by professionals did not depend on the organization they worked for. However, there was a statistically significant difference between the level of training received from foreign and manufacturer-sponsored organizations. The professionals surveyed had relatively little training since they started working. As the number of years of experience in their profession increased, the number of times they participated in manufacturer-sponsored training increased. However, the number of times they participated in domestic, foreign, or postgraduate training was not related to the number of years of experience. Conclusion Medical equipment engineers and technicians are working harder than international professionals. The lack of post-graduate training for healthcare professionals is a concern for the industry.

Background: Regularly participate international High-level in sports athletes national and competitions and engage in intense training, developing endurance and resilience. Measuring blood lactate levels is crucial for improving an athlete’s performance, assessing sports performance, and enhancing the effectiveness of future training. Aim: To study the relationship between lactate levels in the blood plasma and lactate dehydrogenase enzyme activity in Mongolian National Team athletes. Materials and Methods: The study involved 51 athletes from the Mongolian National Team. Anaerobic capacity was assessed using a Monark 894E Ergomedic Peak Bike, designed to apply exercise load. Blood serum lactate level and lactate dehydrogenase enzyme activity were determined using a Biobase BK-280 fully automated biochemical analyzer. Heart rate, peripheral blood oxygen levels, and oxygen saturation were measured using a pulse oximeter. Results: The average age of the participants was 24.04 ± 4.15 years, with an average height of 168 ± 8.78 cm and an average weight of 71.01 ± 7.69 kg. The average BMI was 24.82 ± 4.12 kg/m². Pre exercise lactate levels averaged 3.84 ± 0.75 mmol/L, while post-exercise lactate levels averaged 9.67±3.52 mmol/L. The average heart rate before exercise was 66.04±8.9 bpm, while post-exercise heart rate was 123.6±16.06 bpm. The average VO₂ max was 95.18±2.48. Conclusion The lactate levels before and after exercise among the athletes participating in the study showed significant differences in the age groups 20-29 (p<0.0001). When comparing lactate levels before and after exercise by sport, statistically significant increases were observed in freestyle wrestling and judo athletes (p<0.0001)

Background: According to the World Health Organization (WHO), 6.7 million people die annually due to air pollution caused by solid fuel use, with the majority of deaths resulting from respiratory diseases and cardiovascular conditions. In Mongolia, air pollution ranks as the fourth leading risk factor contributing to mortality, following hypertension, diabetes, and other major health risks. Although there have been numerous studies on outdoor air pollution in Mongolia, research linking indoor air pollution at the household level with the health status of residents remains limited. Aim: To compare indoor PM2.5 concentrations in households of Ulaanbaatar and Darkhan and examine their association with hypertension during the winter season. Materials and Methods: The study was conducted during November and December 2023, and January 2024, involving 240 households in Ulaanbaatar and Darkhan. Indoor PM2.5 concentrations were measured using Purple Air real-time sensors continuously for 24 hours over approximately one month. After measuring indoor air pollution, individuals aged 18–60 years living in the selected households were recruited based on specific inclusion criteria. Blood pressure was measured three times and the average value was recorded. Information on respiratory illnesses was collected through structured questionnaires. Statistical analysis was performed using STATA version 19.0. Results: A total of 241 households participated in the study, with 116 from Ulaanbaatar and 125 from Darkhan. Of the participants, 46.5% were male and 53.5% were female. In terms of housing type, 96 households (39.8%) lived in gers, 97 (40.2%) lived in stove-heated houses, and 48 (19.9%) lived in apartments. Among all participants, 66.0% (n=159) had hypertension and 34.0% (n=79) had normal blood pressure. Among participants aged over 40, 69.9–88.5% had hypertension, which is statistically significantly higher compared to younger individuals (p=0.0001). By body mass index, 75.3% (n=72) of overweight individuals and 78.4% (n=58) of obese participants had hypertension, showing a statistically significant difference compared to participants with normal weight (p=0.0001). The 24-hour average concentration of indoor PM2.5 was measured using the Purple Air device, and the levels in gers and stove-heated houses exceeded the limit set by the MNS 4585:2025 standard (37.5 µg/m³) Conclusion This study identified a relationship between environmental factors, such as air pollution and housing type, and the prevalence of hypertension. The indoor PM2.5 concentration in gers and stove-heated houses was above the standard limit, indicating a negative impact on the health of those residents. Furthermore, the high prevalence of hypertension among participants over the age of 40 and those who are overweight suggests a possible link to lifestyle and environmental conditions.

Background: Particulate matter with an aerodynamic diameter of 2.5 micrometers or smaller (PM2.5) penetrates deep into the alveoli through the respiratory tract and is characterized by its ability to induce oxidative stress, systemic inflammation, and vascular inflammation. Mongolia ranks among the countries with the highest levels of air pollution. In Ulaanbaatar, where more than half of the country’s population resides, wintertime PM2.5 concentrations often exceed 200 μg/m³, which is about eight times higher than the World Health Organization (WHO) guideline value. A study involving 1,200 adults in Ulaanbaatar showed that quality of life deteriorated sharply during periods of high air pollution, with effects more pronounced among individuals who already had impaired respiratory function. Aim: To examine the relationship between indoor household PM2.5 concentrations and lung function indicators among adults in Ulaanbaatar and Darkhan. Materials and Methods: This analytical cross-sectional study recruited adult participants from Ulaanbaatar and Darkhan through targeted sampling. Household air quality was measured using PurpleAir sensors, which were installed in participants’ homes for one month. After exposure measurement, lung function was assessed via spirometry. Statistical analyses were conducted using SPSS version 25.0. Results: A total of 236 participants were included: 114 (48.3%) from Ulaanbaatar and 122 (51.7%) from Darkhan. The sample consisted of 111 men (47.0%) and 125 women (53.0%). The mean indoor PM2.5 concentration was 66.24 μg/m³ (SD 44.87 μg/m³), ranging from a minimum of 7.79 μg/m³ to a maximum of 264.55 μg/m³. Stratification by housing type showed the highest PM2.5 levels in gers (82.34 μg/m³), followed by detached houses (67.34 μg/m³), while apartments had the lowest concentrations (32.24 μg/m³). Correlation analysis revealed statistically significant negative associations between PM2.5 levels and measures of expiratory function, including the FEV1/FVC ratio, peak expiratory flow (PEF), and mid-expiratory flow (FEF25–75). Reduced forced vital capacity (FVC) was observed in 9.4% of participants, reduced forced expiratory volume in one second (FEV1) in 15.3%, and a decreased FEV1/FVC ratio in 3.8%. Conclusion Indoor household PM2.5 concentrations were highest in gers, and expiratory flow-related lung function parameters showed significant negative associations with particulate exposure. This suggests that indoor PM2.5 primarily affects airflow limitation rather than overall lung volumes in this population.

Kidney transplantation is the best alternative treatment for end-stage renal disease and health-related quality of life and survival of the patients are improved compared with dialysis. Worldwide, more than 1.4 million patients with CKD receive renal replacement therapy with incidence growing by approximately 8% annually.1 Unfortunately, despite significant improvement in graft function, kidney transplants can still fail due to acute rejection and chronic allograft nephropathy.2 Kidney biopsy after transplantation, which has evaluated by Banff 09 classification is usefull method for diagnose of transplanted kidney disease.3,4Kidney graft rejection was diagnosed in 10 renal allograft biopsy specimens (bs) obtained from transplant patients followed up at our institute between 2015 and 2016. All specimens were evaluated as satisfactory which show more than 8 glomerulus under the light microscopy. Each renal cortical tissue was divided into two tips: one piece for routine H&E stain and special stains, including Masson’s trichrome, and PAS stain; another piece for immunofluorescence by frozen section, which were stained with IgA, IgM, IgG and complement component (C3, C4, C1q, C4d). All the renal biopsies were examined by the same pathologist.Out of 117 transplantations, 10 episodes of rejection selected. Among the 10 patients, 30% had an acute T cell rejection and 70% had a chronic allograft nephropathy. Interstitial inflammation (i1-7) was present in 7 bs (70%), tubulitis (t1-4,t2-2) in 6 bs (60%), transplant glomerulitis (g1-1, g2-2, g3-1) in 4 bs (40%), transplant interstitial fibrosis (ci1-2, ci2-2, ci3-2) in 6 bs (60%), tubular atrophy (ct1-6, ct2-2, ct3-1) in 9 bs (90%), mesangial matrix increase (mm1-5) in 5 bs (50%), vascular fibrosis intimal thickeness (cv1-3) in 3 bs (30%), arteriolar hyaline thickening (ah1-5) in 5 bs (50%), tubulitis (ti1-6, ti2-3, ti3-1) in 10 bs (100%) and peritubular capillaritis (ptc1-1, ptc2-2, ptc3-1) in 4 bs (40%). C4d deposition was present very mild in wall of the vessels and peritubular capillaries. Because of not good working Methenamin silver stain, we couldn’t demostrate glomerular basement membrane changes (cg) fully.We suggest that histopathological changes of transplant glomerulopathy might be accompanied by inflammation of the microvasculature, such as transplant glomerulitis and peritubular capillaritis. C4d deposition in the wall of the vessels and peritubular capillaritis is not always present in biopsy specimens of transplant glomerulopathy.

BackgroundIgA nephropathy and MPGN are common glomerulonephritis in the world that progresses slowly andrenal function can even remain unchanged for decades. Clinically, it presents by isolated hematuria,proteinuria. Histologically, IgA nephropathy presents with acute glomerular damage, mesangial cellproliferation, endocapillary leucocyte infiltration, and crescent formations, these lesions can undergoresolution with sclerotic healing. Since 2013, renal biopsy has been done at the First Central Hospitalof Mongolia a few times. However, the confirmative diagnosis of IgA nephropathy and MPGN remainunknown in Mongolia by renal biopsy. Therefore, we intended to test renal biopsy techniques andconfirm its diagnosis by renal biopsy at the Second Central Hospital of Mongolia.MethodsUltrasound guided renal biopsy had been done for four patients by nephrologist at the Departmentof Nephrology of the Second Central Hospital of Mongolia. All four specimens were evaluated assatisfactory which show more than 8 glomerulus under the light microscopy. Each renal cortical tissuewas divided into two tips: one piece for routine H&E stain and special stains, including Masson’strichrome, and PAS stain; another piece for immunofluorescence by frozen section, which werestained with IgG, IgM, IgA and complement component 3 (C3). Each case was screened by threepathologists.Results:The case which shows mesengial widening, mesengial hypercellularity under the light microscopyor mesangial granular deposition of IgA and C3 by immunofluorescence was diagnosed as IgAnephropathy. We obtained crescent formation with glomerular adhesion in most cases. In addition, weobserved secondary MPGN in one case, which is caused by hepatitis C virus infection.Conclusion: Probably, it is a new step for developing pathologic diagnosis for nephrology in Mongolia.We needs further study for improving renal biopsy technique and confirming the diagnosis of IgAnephropathy and MPGN using electron microscopy and pathological report by oxford classification forIgA nephropathy.