Background: The World Health Organization (WHO) states that no safe level of lead exposure has been established and compared with adults, children absorb approximately four to five times more lead into their bodies. When blood lead levels reach 3.5 µg/dL, which may lead to decreased intellectual capacity, impaired attention, and learning difficulties, potentially resulting in intellectual disability and behavioral disorders. The nervous system and blood–brain barrier in children and adolescents are not fully developed, making them highly susceptible to the neurotoxic effects of lead. Lead disrupts several neurotransmitter systems, including dopaminergic, glutamatergic, and cholinergic pathways. Dysfunction in these systems—particularly alterations in dopaminergic pathways—is closely associated with symptoms of Attention Deficit Hyperactivity Disorder (ADHD). In Mongolia, previous studies have investigated the association between ADHD and lead levels in hair samples among children; however, no studies have examined the relationship between blood lead levels and ADHD. Determining whether blood lead levels influence ADHD in children will provide a scientific basis for preventive measures and the development of additional treatment strategies to reduce clinical symptoms and support clinical practice. Aim: To investigate the association between blood lead levels and ADHD among school children. Materials and Methods: A household-based analytical cross-sectional study was conducted. A total of 306 children aged 6-14 years were randomly selected according to the study inclusion criteria. The Vanderbilt ADHD Diagnostic Questionnaire was administered to parents/guardians and classroom teachers to identify ADHD cases. Blood samples were analyzed to determine blood lead levels using the NIOSH 8005 standard method with Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) in a laboratory accredited under MNS ISO 17025:2018. Additionally, data on lead exposure risk factors were collected using a 15-item questionnaire administered to parents or guardians through the Google Forms platform. Result: Among the participants, 34 children were diagnosed with ADHD. Of these cases, 67.64% were male and 32.35% were female, yielding a male-to-female ratio of approximately 2:1. Boys were 3.6 times more likely to have ADHD than girls (OR=3.675; 95% CI: 2.276-6.210; p<0.0001). Regarding ADHD subtypes, the predominantly inattentive type accounted for 38.2% (n=13), the predominantly hyperactive type for 52.9% (n=18), and the combined type for 8.8% (n=3). When comparing clinical subtypes by sex, the hyperactive type was more common among boys (60.9%, n=14), whereas the inattentive type was more common among girls (45.5%, n=5). The mean blood lead level among all children was 4.8±2.33 µg/dL. Among children with ADHD, the mean level was 6.16±2.47 µg/dL, while among children without ADHD it was 4.75±2.31 µg/dL, indicating a statistically significant difference between the groups. In examining factors influencing the development of ADHD in relation to children’s morbidity status, repeated illnesses such as anemia, rickets, malnutrition, and recurrent acute febrile diseases were identified as statistically significant risk factors (p=0.012). In contrast, acute conditions of short duration were not found to be significant risk factors. Conclusion 1. Among the children included in the study, 34 (11.1%) were diagnosed with ADHD, and the prevalence was higher in boys than in girls. 2. Blood lead levels showed a statistically significant association with Attention Deficit Hyperactivity Disorder in children.

Background: Polymyositis (PM) is a rare idiopathic inflammatory myopathy characterized by symmetric proximal muscle weakness, elevated muscle enzyme levels, dysphagia, and respiratory muscle weakness. Rhabdomyolysis is a potentially life-threatening condition caused by extensive skeletal muscle breakdown, resulting in myoglobinuria and an increased risk of acute kidney injury and multiorgan complications. The coexistence of rhabdomyolysis in patients with polymyositis is uncommon and may complicate both diagnosis and management. Case Presentation: A 65-year-old man was admitted with fever up to 39°C, generalized skin rash, dysphagia, progressive muscle weakness, dyspnea, decreased urine output, and dark tea-colored urine. Physical examination revealed symmetric proximal muscle weakness, with muscle strength graded 3/5 in both upper extremities and 4/5 in both lower extremities. Neck muscle strength was 4/5. Dysphagia and a generalized skin rash were also present. Laboratory investigations showed markedly elevated creatine kinase (CK) at 9,943.1 U/L, alanine aminotransferase (ALT) at 449.1 U/L, aspartate aminotransferase (AST) at 222.1 U/L, lactate dehydrogenase (LDH) at 1,342.9 U/L, and C-reactive protein (CRP) at 70.6 mg/L. Urinalysis showed blood 3+ and protein 2+, while no erythrocytes were detected on urine sediment microscopy. Electromyography demonstrated myopathic changes, and muscle biopsy revealed inflammatory infiltrates and necrotic muscle fibers. Conclusion Comprehensive assessment of clinical manifestations, laboratory findings, autoantibody testing, electrophysiological studies, and muscle biopsy is essential for the diagnosis of polymyositis complicated by rhabdomyolysis. An integrated diagnostic approach facilitates confirmation of the diagnosis, differentiation from clinically similar disorders, and appropriate treatment selection. Early recognition of rhabdomyolysis and other potentially life-threatening complications is crucial for preventing organ damage and improving patient outcomes.

Background: Musculoskeletal disorders account for 23.1-47.1% of occupational diseases in several countries. Studies have shown that operators of heavy machinery, including tractors and dump trucks, are twice as likely to experience lower back pain compared to workers not exposed to whole-body vibration. Furthermore, research has indicated that acute exposure to vibration can cause vasoconstriction and vascular inflammation. However, limited research has explored the relationship between lower back pain and specific biomarkers, highlighting the need for this study. Aim: This study aimed to compare lower back pain prevalence and muscle inflammation biomarkers among heavy machinery operators. Materials and Methods: A purposive sampling method was used to recruit 15 male participants aged 25-35 years who had worked as heavy machinery drivers for no more than three years. Inclusion criteria were: no alcohol consumption within 24 hours prior to sampling, body mass index (BMI) between 18.5-28.9 kg/m², no prior diagnosis of musculoskeletal disorders, and absence of infectious or non-infectious diseases during the study period. Blood samples were analyzed for Interleukin-6 (IL-6) and Tumor Necrosis Factor-alpha (TNF-α) levels using enzyme-linked immunosorbent assay (ELISA). Results: The mean BMI of participants was 25.89±3.23 kg/m². Over half (53.3%, n=8) exceeded the exposure limit for whole-body vibration. Low back pain was reported by 13 participants (86.7%) over the past six months and by 12 participants (80%) over the past seven days. TNF-α levels did not differ significantly between groups based on low back pain status or vibration exposure. However, IL-6 levels showed a significant increase 24 hours after whole-body vibration exposure (p=0.027). Conclusion Lower back pain was highly prevalent among participants exposed to whole-body vibration. Furthermore, IL-6 levels were elevated among participants reporting lower back pain, regardless of vibration exposure levels.

: Pleurotus ostreatus (Jacq) P. Kumm) is the second cultivated and most popular edible mushroom after Agaricus bisporus in the world. The fruiting bodies of these mushrooms have high nutritional value and are beneficial for health. Pleurotus ostreatus are an interesting source of bioactive glucans and other polysaccharides. This study focuses on the isolation and structural characterization of glucans from the fruiting bodies and stems cultivated mushrooms Pleurotus ostreatus. Methods: Physicochemical properties of fruiting bodies and stems cultivated Pleurotus ostreatus in Mongolia, were studied using standard methods. Glucans were extracted and purified using the precipitation method and Sevag reagent, and functional groups were determined by FT-IR. Conclusion The characteristic absorption bands of the water and alkali-soluble fractions were found near 1070, 1044, 869 and 777-769 cm-1. These IR bands are characteristic of fungal (1→3)(1→6)-β-D- glucans, and indicating these fractions are glucan-type polysaccharides

Background: Stroke is one of the leading causes of mortality and disability worldwide. Understanding sex differences in risk factors, clinical characteristics and death after stroke might provide valuable evidence for prevention and management of stroke. Aim: We aimed to describe sex differences in risk factors, clinical characteristics and death after intracerebral hemorrhage (ICH) and ischemic stroke (IS) using hospital-based registry in 6 districts of Ulaanbaatar, Mongolia. Materials and methods: We used hospital-based stroke registry in Ulaanbaatar Mongolia. From 2019 to 2020, total of 974 patients with acute ICH and 1612 patients with acute IS were enrolled in this study. The severity of stroke was measured by National Institutes of Health Stroke Scale (NIHSS) and Glasgow Coma Scale (GCS). Risk factors for stroke were defined as patient’s history and their medical record. Death after stroke was registered at 28 days and 90 days by follow-up study. A comparison of categorical and continuous variables was analyzed using chi-squared test, Student’s t-test and Mann Whitney U test. Univariable and multivariable logistic regression analyses were also performed. Results: The mean age of ICH patients was 58.41±11.56. There was significant difference in age (59 vs 57, p=0.009) between women and men. Men with ICH were more likely to drink alcohol (35.4% vs 5.2%, p=0.000) and to smoke (37.0% vs 8.4%, p=0.000) and to have arterial hypertension (72.7% vs 58.6%, p=0.000). However, there were no significant differences in other risk factors including atrial fibrillation, diabetes mellitus, prior stroke and other cardiac diseases. There were no sex differences in clinical characteristics including systole and diastole blood pressure, NIHSS scores and GCS. In our study, case fatality rate was 23.8% at 28 days and 1.9% at 90 days after ICH. By multivariable regression analyses, there were no significant association between sex and death at 28 days and at 90 days (OR:0.74; 95% CI:0.52-1.06, OR: 0.80; 95% CI:0.29-2.21).
The mean age of IS patients was 61.07±12.88. The women were older (63 vs 59, p=0.000) than men. Men with IS also were more likely to be current smokers (37.6% vs 9.0%, p=0.000), current drinkers (33.2% vs 3.4%, p=0.000) and to have arterial hypertension (74.7% vs 65.9%, p=0.000). There were no significant differences in other risk factors. For IS patients, there also was no sex difference in clinical characteristics. Case fatality rate was 13.3% at 28 days and 1.1% at 90 days after IS. By multivariable regression analyses, there were no significant association between sex and death at 28 days and at 90 days (OR:0.90; 95%CI: 0.64-1.26, OR:5.16; 95%CI: 0.99-23.9). Conclusion Our study showed sex differences in some vascular factors of both stroke subtypes which emphasized that we need to implement stroke prevention targeting sex-specific risk factors. While clinical characteristics and early mortality of intracerebral hemorrhage and ischemic stroke were not differed by gender.

Background: Globally the incidence of stroke is not decreasing, and the deaths and disabilities caused by stroke is increasing every year, especially in low and low-middle income countries.
Long-term trends in stroke incidence in different populations have not been well characterized, largely as a result of the complexities associated with population-based stroke surveillance.
Having reliable data on stroke morbidity and mortality, as well as periodic identification of long-term trends will be important information for proper prevention planning in the population, monitoring the disease and further improving the quality of health care. Material and Method: A prospective cohort study has been conducted in adult citizens (972409 in 2019, 925367 in 2020) of 6 districts of Ulaanbaatar from the 1st of January, 2019 to 31st of December, 2020. All first-ever and recurrent stroke cases were included using special software, developed for stroke registry, based on the WHO STEPS approach from participating radiology departments of state hospitals, district hospitals, and some private hospitals. Information of stroke death was obtained from forensic institute and state registration office of the capital city.
The trends of stroke incidence and mortality was compared to data between 1998-1999 and 2019- 2020 in UB. Results: The age-standardized crude incidence rate per 100.000 person-years of stroke were 209.0/100.000 (n=1934) in 2019 and 194.0/100.000 (n=1821) in 2020 among adults of UB city. The above results were compared to 1998-1999 studies and the incidence rate declined by 94.0/100.000 in 2019-2020, whereas mortality rate increased by 10.0/100.000 in women aged 16-34. Stroke mortality was 11.6% in 1998 and 26.5% in 1999, while in our study it was 33.87% in 2019 and 29.71% in 2020. Although the incidence of stroke rates has decreased in 1998-1999, the mortality rate has not decreased significantly. Conclusion Morbidity and mortality rates among the population of Ulaanbaatar citizen remain highest in the world, compared to 20 years ago with overall morbidity declining but mortality has not decreased.
In recent years, the Government of Mongolia has been focused on reducing non-communicable diseases, but the primary and secondary prevention and control of stroke in the general population, as well as the acquisition of knowledge attitudes, practices and access to health care still need to be improved.

Background: Stroke is still one of the leading causes of morbidity and mortality worldwide. Registry-based data of stroke are scarce in low and middle-income countries such as Mongolia. We aimed to investigate the incidence and mortality of stroke in adult population of UB Mongolia by stroke registration method. Material and Method: Covering 611265 (≥15 years old) adult citizens of three districts of Ulaanbaatar, a population-based prospective study was done from the first, January of 2019 to 31st, December of 2019. All first-ever and recurrent stroke cases were included using special software, developed for stroke registry, based on the WHO STEPS approach from participating radiology departments of state hospitals, district hospitals, and family clinics. Information of stroke death was obtained from forensic institute and state registration office of the capital city. Results : In a 1-year study period, 1068 (women 39.1%) stroke cases were registered in people with 60.16±13.66 years old. Stroke incidence rate was 169.81/100000 including first-ever and recurrent events. Stroke incidence rate was higher in men and people with 80 and above years old. The ratio between IS and ICH was 1.14:1.0. Stroke mortality was 27.1% and mortality rate was 45.94/100000. The highest rate mortality was in ICH subtype, male population and older people. Conclusion We identified relatively high incidence and mortality rate of stroke in ICH indicating an urgent need for improvement of arterial hypertension control, health education and primary prevention mainly among men.

BACKGROUND. The aim of this study was to investigate the prognostic impacts of drug-eluting stents (DES) and bare-metal stents (BMS) in patients undergoing percutaneous coronary intervention (PCI) and risk factors of stent restenosis. MATERIAL AND METHODS. We conducted a retrospective cohort study based on the Angiographic diagnostic and treatment Department of 3rd State Central Hospital of Mongolia. Patients who had undergone coronary stenting between 2000 and 2017 were recruited and monitored until the end of 2010. RESULTS. Among a total of 4520 selected patients with a mean age of 58±7 years, 2125 subjects had BMS and 2395 subjects had DES. The incidence of stent restenosis and stent thrombosis were significantly lower in the DES (37; 1,5%) group as compared with the BMS (201; 9,4%) group. Patients who have stent restenosis presented comorbidities, such as diabetes 214(47,8%), hypertension 54(22,6%), prior PCI 21(8,2%), re-infarction 12(5,04%), chronic kidney disease 16(6,7%), hyperlipidemia 21(8,2%). СONCLUSION. Implantation of DES was related to better outcomes than for BMS, in terms of reducing restenosis and stent thrombosis after PCI. STEMI patients who have co morbidities have greater risk of stent stenosis and thrombosis

The present study was conducted to assess relationship between drinking water fluoride levels and dental caries among 12 years old school children of 2 districts of Ulaanbaatar city, Mongolia. A cross-sectional analytical study was conducted on 533 school children aged 12 years, selected from 6 schools of 2 districts of Ulaanbaatar city. 533 children were divided into 2 groups according to the fluoride concentration of the waters. The all children were examined oral examination, dental caries was assessed by the DMF-T index. The result of the present study revealed that the caries prevalence in the study population was about 68,9%, and mean DMF-T was 3.05. Water fluoride concentration was highest in Khan-Uul district with 0.622ppm. There was highest prevalence of caries in children who consume water from filtration system in both districts.

There are a lot of influencing factors of facial nerve palsy; experts believe that is most likely caused by a Virus (54%) and Bacterial infections. Noninfectious causes of facial nerve palsy induce tumors (28%) and less commonly influences head trauma (18%). The retrospective analysis of WHO, in 2012. There are some cases of postoperative complication in middle ear surgery is facial nerve palsy and the total recovery outcome of function was not good. From 2013 to 2016 in EMJJ hospital, Mongolia, we enrolled 16 cases with facial nerve damaged in intratympanic canal but we could not recruit some patients with facial palsy over 6 months. Each subject was tested with pure tone test, ABR, Tympanometry. These were performed for the detection of hearing loss after Temporal bone injury. Then we also investigated location of facial nerve damages of patients by MRI and CT before reconstructive surgery. After that surgery, all patients were given corticosteroid treatment (20mg/day) and physical therapy performed such as acupuncture for a week. Study results revealed that 6 cases after 18 days, 2 cases after 30 days, 1 patient after 45 days of reconstructive surgery regained good symmetry. Therefore, we considered that, postoperative treatments like physical therapy with B12, steroid had good benefits for operation result and to shorten the recovery time. There was a patient who had damaged facial nerve in the tympanic segment during Mastoidectomy. In that case, we performed cable nerve grafting using the r.auricularismagnium but we could not recover facial nerve function. Traumatic facial nerve paralysis is the second most common type. We discussed that performing reconstruction surgery within first 3 months after intratemporal facial nerve injury is extremely desirable and more effective. In our opinion, nerve recovery might be not successfully cause of injured myelin sheet of facial nerve during middle ear surgery.