Soil environmental anomalies dominate the responses of net ecosystem productivity to heatwaves in three Mongolian grasslands.

Climate change is causing more frequent and intense heatwaves. Therefore, it is important to understand how heatwaves affect the terrestrial carbon cycle, especially in grasslands, which are especially susceptible to climate extremes. This study assessed the impact of naturally occurring, simultaneous short-term heatwaves on CO2 fluxes in three ecosystems on the Mongolia Plateau: meadow steppe (MDW), typical steppe (TPL), and shrub-grassland (SHB). During three heatwaves, net ecosystem productivity (NEP) was reduced by 86 %, 178 %, and 172 % at MDW, TPL, and SHB, respectively. The changes in ecosystem respiration, gross primary production, evapotranspiration, and water use efficiency were divergent, indicating the mechanisms underlying the observed NEP decreases among the sites. The impact of the heatwave in MDW was mitigated by the high soil water content, which enhanced evapotranspiration and subsequent cooling effects. However, at TPL, insufficient soil water led to combined thermal and drought stress and low resilience. At SHB, the ecosystem's low tolerance to an August heatwave was heavily influenced by species phenology, as it coincided with the key phenological growing phase of plants. The potential key mechanism of divergent NEP response to heatwaves lies in the divergent stability and varying importance of environmental factors, combined with the specific sensitivity of NEP to each factor in ecosystems. Furthermore, our findings suggest that anomalies in soil environment, rather than atmospheric anomalies, are the primary determinants of NEP anomalies during heatwaves. This challenges the conventional understanding of heatwaves as a discrete and ephemeral periods of high air temperatures. Instead, heatwaves should be viewed as chronologically variable, compound, and time-sensitive environmental stressors. The ultimate impact of heatwaves on ecosystems is co-determined by a complex interplay of environmental, biological, and heatwave features.

Estimation of the Carrying Capacity and Relative Stocking Density of Mongolian grasslands under various adaptation scenarios.

Mongolia's vast grasslands, crucial for both environmental and economic stability, are currently facing challenges due to overgrazing, climate change, and land-use changes. Understanding and effectively managing their Carrying Capacity (CC) and Relative Stocking Density (RSD) is essential for maintaining ecological balance. This study rigorously evaluates the CC and RSD of Mongolia's grasslands through an innovative approach that integrates ecological models with socio-economic data, aimed at improving grazing management practices. Data from the National Agency for Meteorology and Environmental Monitoring validates the model, providing precise CC and RSD estimates at the Soum level from 2000 to 2019. The study reveals significant regional variations in CC: northern grasslands exhibit a high CC of 2.8 Sheep Units (SU) per hectare, contrasting with the fragile CC in some southern regions, like the Gobi Desert, where it is as low as 0.3 SU per hectare. Approximately 38.8 % of Mongolia's territory maintains a CC exceeding 1.0 SU per hectare, indicative of sustainable grasslands. In contrast, 41.7 % of the land, primarily in southern regions, shows CCs below 0.5 SU per hectare, highlighting ecosystem vulnerability. The RSD, reflecting livestock numbers relative to CC, averages 1.07, suggesting a high livestock concentration near Ulaanbaatar but a more sustainable density across 43.2 % of the country. The research also explores adaptation scenarios against desertification and degradation, as well as improving pasture accessibility, providing insights for future grassland management strategies. In conclusion, this study emphasizes the need for sustainable land management practices to balance carrying capacity and stocking rates, offering a vital tool for policymakers and stakeholders in grassland conservation.

Aberrant methylation of dipeptidyl peptidase­like 6 as a potential prognostic biomarker for lung adenocarcinoma.

We previously performed the genome-wide screening of aberrantly methylated CpG islands (CGIs) using the paired tumorous and non-tumorous tissues of 12 lung adenocarcinomas (LADC). In comparisons with paired normal lung tissues, dipeptidyl peptidase-like 6 (DPP6) has been identified as the most significantly hypermethylated CGI in LADC. DPP6 is a protein that modulates A-type potassium channels in the somatodendritic compartments of neurons, which play a role in synaptic plasticity. Previous studies have showed that DPP6 is downregulated in cancers, such as acute myeloid leukemia and melanoma, but upregulated in colon cancer, which is attributed to hyper- and hypomethylation, respectively. The present study investigated the methylation and expression levels of DPP6 and its prognostic value in patients with LADC. The DNA methylation and mRNA expression levels of DPP6 in surgically resected LADC tissues were examined by bisulfite pyrosequencing and reverse transcription-quantitative PCR, respectively. The DNA methylation and mRNA expression levels of DPP6 were both significantly higher in LADC tissues compared with in normal lung tissues (n=25; P<0.0001). Overall and disease-free survival rates were significantly higher in LADC with high mRNA expression levels compared with those with low levels. In conclusion, epigenetic alterations in DPP6 were significantly higher in LADC tissues compared with in normal lung tissues, which may contribute to the malignant features and worse prognosis of these patients.

A Dual Leucine-rich Repeat in Proteins from the Eukaryotic SAR Group.

BACKGROUND: Leucine-rich repeats (LRRs) occurring in tandem are 20-29 amino acids long. Eleven LRR types have been recognized; they include plant-specific (PS) type with the consensus of LxxLxLxxNxL SGxIPxxIxxLxx of 24 residues and SDS22-like type with the consensus of LxxLxLxxNxL xxIxxIxxLxx of 22 residues. OBJECTIVE: A viral LRR protein in metagenome data indicated that most of the LRRs (5/6 = 0.83) are represented by the consensus of LxxLDLxxTxV SGKLSDLxxLTN of 23 residues. This LRR shows a dual characteristic of PS and SDS22-like LRRs (called PS/SDS22-like LRR). A comprehensive similarity search was performed under the hypothesis that many proteins contain LRR domains consisting of only or mainly PS/SDS22-like LRR. METHODS: Sequence similarity search by the FASTA and BLAST programs was performed using the sequence of this PS/SDS22-like LRR domain as a query sequence. The presence of PS/SDS22-like LRR was screened within the LRR domains in known structures. RESULTS: Over 280 LRR proteins were identified from protists, fungi, and bacteria; ~ 40% come from the SAR group (the phyla Alveolate and Stramenopiles). The secondary structure analysis of PS/SDS22-like LRRs occurring sporadically in the known structures indicates three or four type patterns of secondary structures. CONCLUSION: PS/SDS22-like LRR forms an LRR class with PS, SDS22-like and Leptospira-like LRRs. It appears that PS/SDS22-like LRR is a chameleon-like sequence. A duality of two LRR types brings diversity.

Propensity score analysis comparing off-pump versus on-pump coronary artery bypass grafting in older adults.

OBJECTIVE: This study aimed to compare the results of off-pump and on-pump coronary artery bypass grafting in older adults and to examine early and late outcomes. METHODS: This study included 226 patients aged ≥ 75 years who underwent isolated coronary artery bypass grafting. Of these, 141 and 85 patients were included in the off-pump and on-pump groups, respectively. Propensity scores were calculated for each case, matched, and compared between the two groups (68 cases in each group), along with mid-term outcomes of survival and major adverse cardiac events. RESULTS: Operative time, red blood cell transfusion volume, and postoperative hospital stay duration were significantly higher in the on-pump group (267 vs 370 min, P < 0.001; 4.3 vs 17.2 units, P < 0.001; and 20.8 vs 35.8 days, P = 0.012, respectively). Postoperative occurrence of new atrial fibrillation was significantly higher in the on-pump group (4.4% vs 27.9%, P < 0.001), and Kaplan-Meier survival analysis showed a significantly worse prognosis in the on-pump group than in the off-pump group (3-year survival rate 90.7% vs 71.5%, log rank P = 0.007). However, there was no statistically significant difference in cardiovascular-related deaths (log rank P = 0.07). CONCLUSIONS: On-pump coronary artery bypass grafting in an older adult population resulted in increased transfusion volume and postoperative occurrence of atrial fibrillation. The mid-term postoperative outcomes were also poorer with on-pump coronary artery bypass grafting. Off-pump coronary artery bypass grafting reduced future all-cause deaths in older adults.

Changes in Vascular Function from Preconception to Postpartum Among Mongolian Women.

Background: Pregnancy is associated with physiological changes to meet the metabolic demands of the growing fetus. To understand adverse pregnancy outcomes it is important to establish vascular changes throughout pregnancy. We examined longitudinal changes in vascular measurements from prepregnancy through postpartum. Materials and Methods: Seventy women planning to conceive in Ulaanbaatar, Mongolia enrolled in this prospective study. Within 6 months, 44 (63%) had conceived; of which 36 (82%) delivered. Ten (28%) developed complex pregnancies and were analyzed separately. Vascular measures included central systolic blood pressure (cSBP), central diastolic blood pressure (cDBP), augmentation index corrected for heart rate of 75 beats/minute (AIx-75), and pulse wave velocity (PWV). Measurements were performed at prepregnancy, second trimester (22-24 weeks), third trimester (34-36 weeks), and 2 months postpartum. Missing values (n = 0-6 per time period) were replaced by multiple imputation. A repeated measures analysis of variance analyzed changes within individual women over the four time points adjusted for age, parity, and body mass index. Results: We observed significant reductions from prepregnancy to second trimester for mean Alx-75 (17.1%-12.6%; p = 0.006) and cSBP (91.7-86.8 mmHg; p = 0.03) but not for cDBP or PWV. Both mean AIx-75 and cSBP increased in third trimester. In the postpartum, cSBP returned to prepregnancy levels, whereas AIx-75 exceeded prepregnancy levels, although this fell short of significance (p = 0.09). Similar vascular patterns were observed in women with complex pregnancies for AIx-75; however, PWV increased from the second trimester and remained higher through postpartum, although not significant. Conclusion: In Mongolian women, we observed a decrease in AIx-75 and cSBP from prepregnancy through second trimester, which resolved postpartum. These results provide an understanding of changes across pregnancies in an Asian country. Future studies should assess vascular changes across pregnancies to determine if it can predict conditions such as pre-eclampsia.

A crucial residue in the hydrophobic core of the solenoid structure of leucine rich repeats.

Leucine rich repeats (LRRs) with 20-30 residues form a super helix arrangement. Individual LRRs are separated into a highly conserved segment with a highly conserved (HCS) and a variable segment (VS). In LRRs short ß-strands in HCS stack in parallel, while VS adopts various secondary structures. Among eleven classes recognized, only RI-like, Cysteine-containing (CC), and GALA classes adopt an α-helix. However, the repeat unit lengths are usually different from each other. We performed some analyses based on the atomic coordinates in the known LRR structures. In the VS consensuses of the three classes, position 8 in the VS part is, in common, occupied by conserved aliphatic residue adopting an α-helix. This aliphatic residue is near to the two conserved hydrophobic residues at position 4 (in the center of ß-strands) in two adjacent HCS parts. The conserved aliphatic residue plays a crucial role to preserve two parallel ß-strands.

The effects of Particulate matter (PМ2.5) pollutants on cancer cells in in vitro model / Монголын Анагаах Ухаан

Introduction@#Air pollution has become one of the major problems in socio-economic and health issues in Mongolia. Among the various hazards of particulate matter (PM) pollutants, microorganisms in PM2.5 and PM10 are thought to be responsible for various allergies and for the spread of respiratory diseases. Recent studies have shown that PM2.5 particles can cause chronic heart failure, heart arrhythmias, and strokes, as well as lung damage, cirrhosis, inflammation, cancer, cardiovascular disease, and metabolic disorders. Furthermore, some studies have concluded that PM2.5 particles in the environment are a risk factor for gastrointestinal, liver, colon, and lung cancer as well as it affects the growth and metastasis of various cancer cells caused by other factors. In our country, the health effects of air pollution and the relationship between the pathogenesis of cancer research are scarce. Therefore, the study of the effects of PM2.5 particles on cancer cell proliferation, migration (metastasis) can provide a significant role for cancer treatment, diagnosis, and prevention.@*Purpose@#Determining the effects of PM2.5 particles on cancer cell proliferation, migration (metastasis) in in-vitro@*Material and Methods@#A human liver cancer cell line (HepG2), human gastric cancer cell line (AGS) were obtained from the central scientific research laboratory in the Institute of medical sciences. HepG2, AGS cells were seeded at a concentration of 1*105 cells/mL in a culture flask and cultured in RPMI-1640 medium supplemented with 10% FBS, 1% antibiotic mix (penicillin, streptomycin) in a humidified atmosphere of 5% CO2 at 37 °C. The cytotoxic effect of PM 2.5 in AGS, HepG2 cells were evaluated by MTT, CCK8 assays. AGS, HepG2 cells were incubated in 96 well plates for 24h then treated with different concentrations (0, 5, 10, 25, 50 and 100 μg ) of Bayankhoshuu, Buhiin urguu, and Zaisan samples for 24h, respectively.@*Results@#Concentrations of 10, 25, and 50 μg/ml of samples collected from the Bukhiin urguu and Zaisan in March increased HepG2 cell growth, while doses of 25, 50 μg/ml of samples collected from Bayankhoshuu in March and December increased HepG2 cell growth. Therefore, concentrations of 25 and 50 μg/ml of samples collected from Bayankhoshuu in March increased AGS cell growth, while concentrations of 25, 100 and μg/ml of samples collected in December increased AGS cell growth. However, no cytotoxic effect was observed in the sample collected from Zaisan in March, whereas the PM2.5 sample enhanced AGS cell growth in dose dependent manner in December.(p <0.05) @*Conclusion@#High levels of heavy metals were detected in samples collected in December from Bayankhoshuu, Bukhiin urguu and Zaisan of Ulaanbaatar. Concentration of 25 μg/ml of samples collected from the Bukhiin urguu and Zaisan in March increased HepG2 cell growth. Concentrations of 25 μg/ml of PM2.5 collected from three regions around Ulaanbaatar increased HepG2 and AGS cell migration.

A strong correlation between consensus sequences and unique super secondary structures in leucine rich repeats.

Leucine rich repeats (LRRs) are present in over 430 000 proteins from viruses to eukaryotes. The LRRs are 20 to 30 residues long and occur in tandem. Individual LRRs are separated into a highly conserved segment with the consensus of LxxLxLxxNxL or LxxLxLxxNxxL (HCS) and a variable segment (VS). In LRRs parallel stacking of short ß-strands (at positions 3-5 in HCS) form a super helix arrangement called a solenoid structure. Many classes have been recognized. All three classes of Plant specific, Leptospira-like, and SDS22-like LRRs which are 24, 23, and 22 residues long, respectively, form a 3(10)-helix in the VS part. To get a deeper understanding of sequence, structure correlations in LRR structures, we utilized secondary structure assignment and HELFIT analysis (calculating helix axis, pitch, radius, residues per turn, and handedness) based on the atomic coordinates in crystal structures of 43 LRR proteins. We also defined three structural parameters using the three unit vectors of the helix axes of 3(10)-helix, ß-turn, and LRR-domain calculated by HELFIT. The combination of the secondary structure assignment and HELFIT reveals that their LRRs adopt unique super secondary structures consisting of a 3(10)-helix and one or two Type I ß-turns. We propose one structural parameter as a geometrical invariant of LRR solenoid structures. The common LxxLxxL sequence (where "L" is Leu, Ile, Val, Phe or Cys) in the three classes is an essential determinant for the super secondary structures providing a medium range interaction.

Involvement of Vitamin D in Immune system / Монголын Анагаах Ухаан

@#Research of function of vitamin D on immune system has been studying since the study revealed that vitamin D receptor is expressed on the surface of the immune cells. 1,2-dihydroxyvitamin D3 [1,25(OH)2D], physiologically active form, can be generated through hydroxylation of 25-hydroxyvitamin D3 [25(OH)D], inactive form of vitamin D, in a liver, connecting with specific VDR make biological action. Vitamin D make different biological actions depends on connecting with different immunological cells. Some studies indicated that Vitamin D plays pivotal role in antibacterial innate immune responses through regulating reaction of the main cells as macrophages and dendritic cells. Moreover, calcitriol, the active form of vitamin D, is connected with VDRE, modulates the innate immune response through directly inducing expression of catelicithin and β-defensin as antimicrobial peptides, reducing secretion of IL-1b, IL-6, TNF-a, RANKL, COX-2 as proinflammatory cytokines and increasing production of IL-10, an anti-inflammatory cytokine. Vitamin D plays in proliferation and differentiation of T and B cells and regulates the activities of over 500 genes. Vitamin D differently impacts on per se stages of T cells’ proliferation. Vitamin D indirectly mitigates the differentiation from immature B cells to plasma B cells while it directly impacts on regulation of overloaded production of antibodies in plasma B cells. In conclusion, vitamin D modulates the innate- and adaptive immune response through regulation on activation of APCells, proliferation and differentiation of immune cells, secretion of some antibacterial peptides.

Super Secondary Structure Consisting of a Polyproline II Helix and a ß-Turn in Leucine Rich Repeats in Bacterial Type III Secretion System Effectors.

Leucine rich repeats (LRRs) are present in over 100,000 proteins from viruses to eukaryotes. The LRRs are 20-30 residues long and occur in tandem. LRRs form parallel stacks of short ß-strands and then assume a super helical arrangement called a solenoid structure. Individual LRRs are separated into highly conserved segment (HCS) with the consensus of LxxLxLxxNxL and variable segment (VS). Eight classes have been recognized. Bacterial LRRs are short and characterized by two prolines in the VS; the consensus is xxLPxLPxx with Nine residues (N-subtype) and xxLPxxLPxx with Ten residues (T-subtype). Bacterial LRRs are contained in type III secretion system effectors such as YopM, IpaH3/9.8, SspH1/2, and SlrP from bacteria. Some LRRs in decorin, fribromodulin, TLR8/9, and FLRT2/3 from vertebrate also contain the motifs. In order to understand structural features of bacterial LRRs, we performed both secondary structures assignments using four programs-DSSP-PPII, PROSS, SEGNO, and XTLSSTR-and HELFIT analyses (calculating helix axis, pitch, radius, residues per turn, and handedness), based on the atomic coordinates of their crystal structures. The N-subtype VS adopts a left handed polyproline II helix (PPII) with four, five or six residues and a type I ß-turn at the C-terminal side. Thus, the N-subtype is characterized by a super secondary structure consisting of a PPII and a ß-turn. In contrast, the T-subtype VS prefers two separate PPIIs with two or three and two residues. The HELFIT analysis indicates that the type I ß-turn is a right handed helix. The HELFIT analysis determines three unit vectors of the helix axes of PPII (P), ß-turn (B), and LRR domain (A). Three structural parameters using these three helix axes are suggested to characterize the super secondary structure and the LRR domain.

Study on influence of the CpG DNA on activation of IFN-γ signaling transduction regulatory proteins / Монголын Анагаах Ухаан

Introduction@#When human body encounters external pathogens primary/innate immunity cells are activated by recognizing them and secondary/adaptive immunity is activated consecutively. In our previous study, we revealed that there is a synergistic action between TLR9 and IFN-γ signaling in the endothelial cells. @*Purpose@#To determine the role of negative and positive regulator proteins on the IFN-γ/TLR9 signaling pathway. @*Methods@#In this study, murine endothelial cell (END-D) culture was used. END-D cells pre-treated with TLR9 ligand CpG DNA and then stimulated with IFN-γ. The negative (SHP-2, SOCS1, PIAS1) and positive (p38) regulator protein expression was detected by Western blotting. @*Results and Conclusion@#Treatment by TLR9 ligand CpG DNA and IFN-γ increased positive regulator p38 phosphorylation in 0.5 hour. CpG DNA inhibited IFN-γ negative regulator PIAS1 protein expression in 6 hour and SOCS1 and SHP-2 expression could not affect in 4 hour.

Role of negative regulators on the TLR7 ligand/IFN-γ signaling in the endothelial cells / Эрүүл мэндийн лаборатори

Introduction@#Toll like receptors (TLRs) are a class of proteins that key role in the innate immune system. The SOCS1 and SHP2 proteins are negative-feed loop inhibitors of signaling of JAK/STAT and TLRs pathways.@*Purpose@#To determine negative regulator protein activation which is activated through TLR7 ligand/IFN-γ signal transduction in endothelial cells. @*Methods@#We used mouse aortic linear endothelial cell (END-D); protein expressio was detected by western blotting @*Results@#We analyzed a time dependent stimulation effects of negative regulator proteins stimulated by TLR7 ligand/IFN-γ in endothelial cell cultures. Imiquimod of 10 μg/ml treatment of 1 hr was followed by 100 ng/ml IFN-γ stimulation for 1-8hr to analysis of negative regulator SOCS1 and SHP2 protein expression. </br> In untreated cells, there was low activations of negative regulator SOCS1 and SHP2 proteins. IFN-γ stimulation alone had increased SOCS1 and SHP2 protein expressions, also imiquimod treatment highly <i>elevated</i> SOCS1 and SHP2 expressions. However imiquimod and IFN-γ doubled treatment have decreased activation of negative regulator SOCS1 and SHP2 proteins. These findings suggest SOCS1 and SHP2 proteins are inhibitors in the TLR7 ligand/IFN-γ signaling. @*Conclusion@#Negative regulators, SOCS1 and SHP2 strongly suppressed activations of TLR7 ligand/IFN-γ signaling

The effect of regulator proteins on the IFN-γ/TLR9 synergistic signal transduction / Эрүүл мэндийн лаборатори

Introduction@#When human body encounters external pathogens primary/innate immunity cells are activated by recognizing them and secondary/adaptive immunity is activated consecutively. Immune cell surface receptors, called Toll-like receptors (TLRs) recognize and bind pathogens. In our previous study, we revealed that there is a synergistic action between TLR9 and IFN-γ signaling in the endothelial cells.@*Purpose@#To determine the role of negative and positive regulatory proteins on the IFN-γ/TLR9 synergistic signaling pathway@*Materials and Methods@#This study was held in the Core Laboratory, Science Technology Center, Mongolian National University of Medical Sciences (MNUMS). In this study, murine endothelial cell (END-D) culture was used. The negative and positive regulator protein expression was detected by Western blotting. @*Result@#Result of immunoblotting assay indicated that CpG DNA enhanced IFN-γ positive regulator protein p38 phosphorylation in the endothelial cells. Treatment by TLR9 ligand CpG DNA and IFN-γ increased p38 activation in 0.5 hour and 1 hour. CpG DNA inhibited IFN-γ negative regulator SOCS1 protein expression in 4 hr and 8 hr. Therefore, TLR9 ligand CpG DNA increased IFN-γ signal transduction in the endothelial cell line.@*Conclusion@#TLR9 ligand CpG DNA has decreased IFN-γ negative regulator protein SOCS1 expression. CpG DNA has increased IFN-γ positive regulator protein p38 phosphorylation.

Grassland productivity and carbon sequestration in Mongolian grasslands: The underlying mechanisms and nomadic implications.

BACKGROUND: Quantifying carbon (C) dioxide exchanges between ecosystems and the atmosphere and the underlying mechanism of biophysical regulations under similar environmental conditions is critical for an accurate understanding of C budgets and ecosystem functions. METHODS: For the first time, a cluster of four eddy covariance towers were set up to answer how C fluxes shift among four dominant ecosystems in Mongolia - meadow steppe (MDW), typical steppe (TPL), dry typical steppe (DRT) and shrubland (SHB) during two growing seasons (2014 and 2015). RESULTS: Large variations were observed for the annual net ecosystem exchange (NEE) from 59 to 193gCm-2, though all four sites acted as a C source. During the two growing seasons, MDW acted as a C sink, TPL and DRT were C neutral, while SHB acted as a C source. MDW to SHB and TPL conversions resulted in a 2.6- and 2.2-fold increase in C release, respectively, whereas the TPL to SHB conversion resulted in a 1.1-fold increase at the annual scale. C assimilation was higher at MDW than those at the other three ecosystems due to its greater C assimilation ability and longer C assimilation times during the day and growing period. On the other hand, C release was highest at SHB due to significantly lower photosynthetic production and relatively higher ecosystem respiration (ER). A stepwise multiple regression analysis showed that the seasonal variations in NEE, ER and gross ecosystem production (GEP) were controlled by air temperature at MDW, while they were controlled mainly by soil moisture at TPL, DRT and SHB. When air temperature increased, the NEE at MDW and TPL changed more dramatically than at DRT and SHB, suggesting not only a stronger C release ability but also a higher temperature sensitivity at MDW and TPL. CONCLUSIONS: The ongoing and predicted global changes in Mongolia likely impact the C exchange at MDW and TPL more than at DRT and SHB in Mongolia. Our results suggest that, with increasing drought and vegetation type succession, a clear trend for greater CO2 emissions may result in further global warming in the future. This study implies that diverse grassland ecosystems will respond differently to climate change in the future and can be seen as nature-based solutions (NBS) supporting climate change adaptation and mitigation strategies.

ДУНД ЧИХНИЙ ИДЭЭТ ҮРЭВСЛИЙН ЧАМАРХАЙ ЯСНЫ БОЛОН ГАВАЛ ТАРХИНЫ ХҮНДРЭЛИЙН ТОХИОЛДОЛ, ОНОШИЛГОО ЭМЧИЛГЭЭ / Шинэ санаа Шинэ нээлт

@#BACKGROUND. The most complications of inflammation of the middle ear temporal bone and skull brain are otitis media, suppurative otitis media, meningitis and skull brain abscess. Aim:To diagnose otitis media, to find the complication of suppurative skull brain and to study the treatment issues as well as to decrease the complication. METHOD. We treated that the patients who was treated the otitis media and complicated with suppurative skull brain between 2014-2015, also the treatment was studied by us in department of otolaryngology surgery of Shastin Central Hospital. RESULTS. In our study, we found the following results: It was a high prevalence with chronic otitis media with effusion in 60 (28.8%) people of younger age group with 25-35 years old. It was a female preponderance with 66% by prevalence. Chronic otitis media with effusion 120 (57.6%), chronic otitis media with mastoiditis 79 (37.9%), total number of patients chronic otitis media with and without mastoiditis 199 (95.5%). It shows disease are easy to throne to the complicated stage of its disease. There was 1 case (0.48%) with intracranial complication. We manage the 8 (4%) patients by antibiotic therapy, 200 (96%) patients by combined with medical and surgical therapy with average 9-12 days of hospital bed days. During 2014-2015, there was only 1 case with intracranial complication from chronic otitis media, shows our early diagnostic level of medical service are quite well. CONCLUSION. Therefore we conclude that prevention, early diagnosis are the main way to decrease the disease. The most important issue is to manage acute otitis media as early as possible before converting it chronic form.

EFFECT OF TLR7 LIGAND ON SIGNAL TRANSDUCTION OF INTERFERON GAMMA / Шинэ санаа Шинэ нээлт

@#BACKGROUND: Toll like receptors (TLRs) are a class of proteins that key role in the innate immune system. TLR7 is expressed on monocytes, macrophages and dendritic cells, T cell, B cell and eosinophiles. TLR7, originally identified as recognizing imidaquinoline, loxibrine, broprimine and ssRNA, ssRNA viruses such as vesicular stomatitis virus, influenza A virus and human immunodefiency virus. It is known that virus ssRNA affects signaling molecule of IFN-y. Objective: To determine gene and protein activation of IFN-y signal transduction by TLR7 ligand in the endothelial cells. MATERIAL: In study we used mouse aortic linear endothelial cell which is cultured (END-D) in 5% heat- inactivated fetal calf serum (FCS), medium (DMEM) containing antibiotic mix(penicillin G, streptomycin, amphotericin B) at 37°C (5% CO2). Endothelial cells treated with synthetic IFN-γ and imiquimodligands, then the NO (nitric oxide) concentration in the supernatant is determined by Griess reagent. Endothelial cells are cultured in 6 well cell culture plate and in each well 2*104cells are expected to be grown for 24 hours of culture. Then, the cells are treated with synthetic IFN-γ and имиквимод ligand for 6 hours and the NO signaling gene activation iNOS mRNA expression which is induced by IFN-γ is determined by RT-qPCR. Endothelial cells are cultured in 12 well cell culture plate and in each well 2*104 cells are expected to be grown for 18 hours of culture. Then, the cells are treated with synthetic IFN-γ and imiquimodligands for 24 hours and the NO signaling protein iNOS expression which is induced by IFN-γ is determined by western blotting. The experiment was conducted as representation mean of at least three test results. The difference between statistical probabilities is determined by the “Students” t test. The p<0.01 value is assumed to be statistically different. RESULTS: TLR7 ligand imiquimodaugmented interferon gamma induced nitric oxide production TLR7 ligand imiquimodincreased interferon gamma induced iNOS mRNA gene expression. TLR7 ilgand imiquimodup-regulated interferon gamma induced iNOS protein expression. CONCLUSIONS: TLR7 ligand imiquimod augments IFN-γ signaling in the endothelial cells. This synergistic effect has revealed in the levels of gene and protein expression.

The effect of TLR9 ligand on IFN-ү signaling / Эрүүл мэндийн лаборатори

Introduction@#The aim of this research project is to elucidate the crosstalk of innate and adaptive immune reactions against the DNA containing bacteria.@*@#This study held in the Core laboratory, Science Technology Center, Mongolian National University of Medical Sciences (MNUMS). Murine aortal endothelial cells, END-D cultured and the cell viability checked by MTT assay. In addition, the NO production, protein and gene expression studied by Griess Reagent assay, R.T-PCR and immunoblotting, respectively. @*Results@#0.1µM, 1µM and 10µM of TLR9 ligand exhibited no cytotoxic action against the cells by MTT assay. IFN-ү alone induced NO production in END-D cells. In the other hand, TLR9 ligand at 0.1µM, 1µM and 10µM up-regulated IFN-ү induced NO production in dose dependent manner. RTPCR results exhibit that TLR9 ligand up regulates iNOS mRNA. Immunoblotting analysis showed the enhanced iNOS protein expression and phosphorylation of STAT1 in cells pre-treated with TLR9 ligand.@*Discussion@#We have demonstrated CpG DNA, TLR9 ligand, up-regulates IFN-ү induced NO via enhanced IFN-ү signaling. The result of Western Blotting and RT-PCR support the up-regulation of NO. CpG DNA can be used as agent against virus and bacteria. Further research need to be conducted. @*Conclusion@#TLR9 ligand, CpG DNA up-regulates IFN-ү induced NO production in time and dose dependent manner. TLR9 ligand augments the expression of iNOS mRNA and STAT1 phosphorylation in response to IFN-ү.

SURGICAL REHABILITATION OF NERVUS FACIALIS LESION / Шинэ санаа Шинэ нээлт

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.

Results of the otosclerosis surgery treatment / Шинэ санаа Шинэ нээлт

Otosclerosis is a disease that involves the cochlea and it is developed when the structure ofconnecting tissue in the area of stapedius and the oval window has changed and become unmovable.Consequently, conductive hearing loss and therefore severe sensorineural hearing loss are caused.The causes of otosclerosis have not been discovered yet but many factors impact on this disease. Anyresearch works has not been done on otosclerosis in Mongolia until now and we have conducted theresearch in 2008-2013. Therefore, we aimed to identify the hearing condition after surgery treatmentof otosclerosis.41 patients /47 ears/ who were diagnosed of having otosclerosis with conductive hearing loss, nomiddle ear infection through the comprehensive ear and hearing examinations were selected in thisstudy which was done at EMJJ Clinics between 2007 and 2013. The hearing improvement after thesurgery has been tested under bone and air conduction frequency 500, 1000, 2000, 4000, 8000 Hzand the results before and after the surgery were statistically processed on Excel 2010 and SPSS 17.0software programs. Stapedotomia and Stapedoectomia surgery approaches were applied and afteropening of attics, the hearing bones are palpated and the diagnosis of stapes otosclerosis is confirmedby the surgeon, who removes the stapes. Then a titanium K-piston (prosthese or implant) is thenplaced into this opening and connected to the malleus, or the incus.Out of 41 patients (85.4% female) involved in the study and 36 people had one ear side otosclerosisand 5 people had both ear otosclerosis. After the surgery 25 patients did not have dizziness andvomiting symptoms and 14 patients did not have dizziness with movement after 12 hours, andfor 4 patients all symptoms were disappeared after 24 hours. As for the result from the hearingexamination after 21, 60 days of the surgery, bone conduction was normal, air conduction, andhearing for 32 patients improved completely, and after 120 days of the surgery, the hearing of 33patients improved completely, bone conduction became 2000 Hz at 4000 Hz frequency 12-15 dB,average of air conduction 15,4±10,1 dB, bone-air gap 10,4±3,1 dB for 5 people, and bone conduction2000 Hz-4000 Hz, at 8000 Hz frequency 20-40dB, air conduction became 25-45dB 10,4±5,1db for 9patients and all patients had no hearing loss except for 4 people who still had tinnitus.After surgery stapedotomia and stapedoectomia for the otosclerosis, the hearing improvement was95.2% and it has been concluded that there is full possibility to perform surgeries of stapedotomia andstapedoectomia for the otosclerosis in Mongolian situation.