Background: Globally, gastric cancer accounts for 1,089,000 new cases and 769,000 deaths annually, ranking fifth in overall cancer incidence and third in cancer-related mortality. The aim to determine HER2 expression in patients with gastric cancer and to evaluate its correlation with clinical and immunological biomarkers, as well as the need for further laboratory diagnostics. Aim: To determine HER2 expression in patients with gastric cancer and to evaluate its association with clinical and immunological biomarkers, as well as the potential need for further laboratory diagnostics. Materials and Methods: A retrospective study was conducted using archived materials from patients with gastric cancer at the Clinical Pathology, Molecular Genetics, and Pathology Laboratories of the National Cancer Center of Mongolia, covering the period from 2019 to June 2025. HER2 protein expression in tumor tissue was assessed using immunohistochemistry (IHC), and chromogenic in situ hybridization (CISH-HER2) was employed to confirm gene amplification. Statistical analysis was performed using the Prisma-10 software. Results: In our study, among 210 cases of gastric cancer evaluated by IHC for HER2, 46 (21.9%) were HER2-positive and 164 (78.1%) were HER2-negative. When comparing patients with gastric cancer stratified into HER2 1+ (negative) and HER2 3+ (positive) groups, no statistically significant differences (p < 0.05) were observed in age, sex, tumor location (surgically resected tissue), morphology, or disease stage. However, a higher proportion of males was noted in the HER2 3+ group (80.9%), though this did not reach statistical significance (p = 0.0879). Significant associations were found with tumor markers. Elevated serum CA-72-4 (>5 ng/mL) was more frequent in the HER2 3+ group (58.8%; p = 0.0069). In contrast, elevated CA-19-9 (>35 U/mL) was more common in the HER2 1+ group (93.5%; p = 0.0117), and elevated CEA (>6.9 U/mL) was also predominant in the HER2 1+ group (90.6%; p = 0.002). These findings suggest that HER2 3+ status predominates in cases with elevated CA-72-4, which may influence diagnostic strategies and HER2-targeted therapies (e.g., trastuzumab). Conversely, elevated CA-19-9 and CEA were more associated with HER2 1+ status, indicating a need for further detailed investigation of these markers in relation to HER2 expression. In patients evaluated by CISH for HER2 expression, stratification into HER2-positive and HER2-negative groups revealed no statistically significant differences (p < 0.05) in age, sex, tumor location, morphology, stage, or serum tumor markers (CA-72-4, CA-19-9, CEA). This suggests that HER2 status (positive/negative) may be independent of these variables. Although HER2 positivity was higher in poorly differentiated tumors (48% vs. 30.6% negative; p=0.1414) and in stage IV disease (50% vs. 39.3% negative; p=0.2607), these differences were not statistically significant. Elevated serum markers (CA-72-4, CA-19-9, CEA) were observed but showed no significant correlation with HER2 status. Conclusion Determining the molecular profile of gastric cancer patients can significantly contribute to refining clinical diagnosis, developing treatment strategies, enhancing therapeutic outcomes, and improving patients’ quality of life.

BACKGROUND: There are two general types of age-related macular degeneration: dry and wet. During wet or neovascular age-related macular degeneration new abnormal vessels grow and leak in the macula. As anti-vascular endothelial growth factor (anti-VEGF) was invented, it revolutionized the treatment of nAMD by inhibiting the progress of this disease. The incidence of AMD increases as life expectancy grows and there is a growing need to study this disease. We aimed to evaluate the outcome of anti-VEGF therapy for the treatment of nAMD and the incidence of ocular serious adverse events (SAE) after injections.. METHODS: In our retrospective, single-center study, medical records of patients receiving a single dose of anti-VEGF treatment (Bevacizumab) for nAMD between 17th of April, 2016 and October, 2017 were evaluated. Outcome measures were the change in the baseline visual acuity (VA) score at post-injective month one, incidence of ocular SAE and patients’ baseline characteristics affecting VA. Patients, whose treatment were started before April 2016 and had anti-VEGF treatment for the diseases other than nAMD, were excluded.. RESULTS: 15 eyes in 15 patients between 52 and 85 years of age received single dose of anti-VEGF (Bevacizumab/Avastin) injection. The mean baseline VA improved from pre-injective average of 0.21 to post-injective 1-month average of 0.37 by Snellen. Furthermore, there was no vision loss or other severe adverse effects, such as endophthalmitis, vitreous hemorrhage, retinal detachment, traumatic cataract after 4 weeks. CONCLUSION: Anti-vascular endothelial growth factor therapy has promising short-term outcomes on treating neovascular age-related macular degeneration.

BACKGROUND: Pterygium is a fibrovascular wing shaped encroachment of conjunctiva onto the cornea. Although the pathogenesis remains obscure, the ultraviolet radiations (UVR), especially UVR-A and UVR-B (290-400 nm), are considered the most dangerous in developing pterygium among other environmental factors (hot, dry, windy, dusty and smoky environments and hereditary factors. The main histopathological change in primary pterygium is elastotic degeneration of conjunctival collagen. Patient complaints include foreign body feeling and visual loss due to corneal astigmatism or growth over the pupil and cosmetic problems. Anti-inflammatory drugs and lubricants have an important role minimizing the patient’s discomfort, but they do not cure the disease. After surgical removal there are still many recurrences regardless of the method used. Autologous conjunctival grafting seems to be the best method, given both the low recurrence rate and high safety. As described first by Kenyon et al. in 1985, a conjunctival autograft reported a recurrence rate of 5.3% with infrequent and relatively minor complications. The primary disadvantage of this technique is the prolonged operative time required when compared to the bare sclera technique. These disadvantages are outweighed by the lack of sight-threatening complications and the relatively low recurrence rate, which made this procedure gain popularity in many centers. The application of intraoperative 0.02% mitomycin C for the 5 minutes is efficient in reducing the recurrence rate to a minimum. METHODS: This retrospective case series, single center study was conducted on 239 patients, who underwent pterygium excision from Jan 2017 to Dec 2017 at the Department of Ophthalmology of the First Central Hospital. All patients had a detailed ophthalmic examination before the surgical intervention. Data were collected through a prepared questionnaire. Postoperative follow-up examination sheets were evaluated. Data for recurrence rate of pterygium excision were collected and analyzed by using SPSS version 17.. RESULTS: Among the 239 patients, who underwent an operation, 37.2% (n=89) were male and 62.8% (n=150) were female. Participants’ age ranged from 29 -70 years with mean age of 49.5 years old. There is no statistical significance between the stages of the disease and its post-operative outcome in the patients, who underwent pterygium excision surgery in 2017. Postoperative pterygium recurrence was in 9 patients (3.8%); 5 (55.5%) out of all 9 patients with recurred pterygium had underwent pterygium excision without conjunctival autograft. MMC was not used intraoperatively for all 9 (3.8%) patients with recurrence post pterygium excision. CONCLUSION: The relationship between pterygium stage and its post-operative recurrence was not statistically significant (P=0.683). The recurrence rate after pterygium excision with conjunctival autograft was low (P≤0.001) which showed significant statistically. There was no recurrence after pterygium excision with MMC (P≤0.001). The results of studies from Canada, Hong-Kong, India, Philippines and Iran were similar to our outcome.

Эвэрлэгийн цагаа, эвэрлэгийн бусад эмгэгийн үед төгс эмчилгээний арга нь эвэрлэг шилжүүлэн суулгах юм. Deep Anterior lamellar keratoplasty (DALK) мэс засал нь гэмтсэн эвэрлэгийн стромын давхарга болон эпителийг бүхэлд нь аван эрүүл эндотели болон десцемет давхаргыг нь үлдээн хийдэг хагалгаа юм. DALK мэс заслын үед Мухамед Анварын том бөмбөлгөн (“Big Bubble” technique) техникийг дэлхий дахинд өргөн ашигладаг ба үүнийг өөрөөр десцеметийн давхаргыг ил гаргах техник (Descemet’s baring technique) гэж нэрлэдэг. Энэ техникийн үед агаарыг эвэрлэгийн стромлуу шахаж өгдөг ба тухайн шахсан агаар нь стромыг десцеметийн давхаргаас салган гэмтсэн эдүүдийг эрүүл эдээс тусгаарлана. Сүүлийн хэдэн жил том бөмбөлгөн техникээр Deep Anterior lamellar keratoplasty (DALK) хагалгааг олон удаа хийх явцад Дуа-гийн давхаргыг олж нээсэн. Энэхүү судалгаанд Дуа-гийн давхаргын онцлог шинж чанар, анатомийн байрлал, түүний нотолгоо болон эмнэл зүйн ач холбогдол хэрэглээг судалсан.

Introduction: Base excision repair (BER) is mainly responsible for the correction of small base changes of DNA damage. BER pathway involved many enzymes including OGG1 and XRCC1. The defective DNA repair is associated with an increased risk of various cancers including hematologic malignancies-leukemia and myelodysplastic syndrome (MDS). However, it is deniably these polymorphisms alter the susceptibility and clinical outcome of MDS patients. The aim: This study was to evaluate the impact of polymorphisms in gene encoding one protein of BER system: XRCC1 Arg399Gln in MDS and healthy population. Methods: In this study, we recruited 60 health control group [median 47.9 years, 9 MDS subjects [median 56.6 years] were included in this study. Genotyping was carried out by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Allele and genotype frequencies were calculated by direct counting. Result: The frequencies of genotypes of XRCC1 Arg399Gln were as follows: Arg /Arg 1 (11%), Arg/Gln 6 (66%), Gln/Gln 2 (22%) in MDS and Arg /Arg 18.4%, Arg/Gln40%, Gln/Gln41.6% in health control for XRCC1 Arg399Gln. The result revealed that genotypes Arg399Gln increased the risk of MDS In conclusion this study is the first to analyze XRCC1 SNPs and their associated risk of MDS in Mongolian samples. To fully understand the role of DNA damage and DNA repair in the MDS, prospective studies are needed and other genes (OGG1 Ser326Cys, MUTYH Gln324His, APE Asp148Glu) of base excision repair pathway should be analyzed.

INTRODUCTION:According to the report from 2010, Mongolian water consumption was 550 million cubic meter andapproximately 9.1% of the total Mongolian population obtain their water from inadequate hygiene waterresources - springs and rivers. Due to non-hygiene water usage has caused water-born communicableand non communicable diseases among the population. In the last years there has been issue of pollutionof one of the Mongolia’s more representative river Selenge and its following rivers -Kharaa, Orkhon andit is necessary to evaluate water pollution of these rivers.GOAL:To determine water chemical and biological pollution of Kharaa and Orkhon river and to evaluate waterqualityMaterials and MethodsWe collected water, sediments and macro invertebrates sample from three points of river -upstream,midstream, downstream and for Kharaa river the samples were collected from Tunkhel, Mandal andBayangol soum, fo Orkhon river the sequence was Orkhontuul, Orkhon, Khushaat soum. Samples werecollected June, August, October of 2011, 2013.In water sample, we determined physic-chemical 15 parameters including temperature, pH, total dissolvedsolids, conductivity, smell, color, hardness, sulfate, chloride, nitrate, nitrite, ammonia, dissolved oxygen,biological oxygen demand and mercury using their standard methods. Macro invertebrate samples werecollected to evaluate water quality and we determined mercury in sediments and macroinvertebratesamples to evaluate mercury contamination.RESULT:Physic-chemical results of the water showed that water of Kharaa, Orkhon rivers were classified lowmineralized, soft water and nutrient pollution indicators for ‘slightly polluted’category. For dissolved andbiochemical oxygen, they were belong to the category of ‘pure water’.There were no correlation between 2012 and 2013 results and mercury in water, sediments and macroinvertebrates were qualified standard value.CONCLUSION:According to research results water quality of Kharaa, Orkhon river was good and have less pollution andit is possible to use in household consumption after proper cleaning and disinfection.