• Tuberculosis and Respiratory Diseases
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• v.44 no.3
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• pp.470-478
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• 1997

Background : Phagocytosis is probably the first step for mycobacteria to be virulent in host because virulent strains are more readily phagocytosed by macrophage than attenuated strains. According to the traditional concept, multi-drug resistant strains have been regarded as less virulent. However, this concept has been challenged, since recent studies(reported) showed that the degree of virulence and drug-resistance is not related. The purpose of this study is to evaluate whether the phagocytic activity of M.tuberculosis by peripheral blood mononuclear cells(PBMC) is different according to drug-resistance or host factor. To evaluate this, we estimated the difference of phagocytic activity of drug-resistant and drug-sensitive M.tuberculosis and also estimated the phagocytic activity of PBMC from intractable tuberculosis patients and healthy controls. Methods : PBMC from ten intractable tuberculosis patients and twelve healthy control, and three different strains of heat-killed M.tuberculosis, ie, ADS(all drug sensitive), MDR(multi-drug resistant), and ADR(all drug resistant) were used. After incubation of various strains of M.tuberculosis with PBMC, the phagocytic activity was evaluated by estimating proportion of PBMC which have phagocytosed M.tuberculosis. Results : Drug-resistant strains of M.tuberculosis were phagocytosed easily than drug sensitive strains(Percentage of PBMC phagocytosed M.tuberculosis in healthy control : ADS : $32.3{\pm}2.9%$, ADR : $49.6{\pm}3.4%$, p = 0.0022, Percentage of PBMC phagocytosed M.tuberculosis in intractable tuberculosis patients : ADS : $34.9{\pm}3.6%$, ADR : $50.7{\pm}4.5%$, p = 0.0069). However, there was no difference in phagocytic activity of PBMC from healthy control and intractable tuberculosis patients. Conclusion : Drug-resistant strains of M.tuberculosis were phagocytosed easily than drug sensitive strains and host factors does not seems to influence the phagocytosis of M.tuberculosis.

• Economic and Environmental Geology
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• v.52 no.4
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• pp.259-274
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• 2019

Using portable XRF and SWIR analyzer, the characteristics of element dispersion and wallrock alterations induced by interaction between hydrothermal fluids and host rocks were investigated and ore exploration factors were estimated for the orogenic-type Samgwang Au deposits. On this purpose, in-situ measurements were conducted for 804 spots at regular intervals with a total of 4,824 times for host rocks, consisting of schist and gneiss, and altered wallrocks contacted with quartz veins in the Bonhang adit of the deposit, and the results were compared with quantitative data obtained by XRF and ICP analysis. The regression coefficients are 0.88 for major elements and 0.56 for trace elements, excluding V. For polished rock slabs, better results came out for major elements, 0.97 and for trace elements, 0.65. In altered wallrocks contacted with quartz veins, elements such as Fe, Zn, and Rb exhibit positive correlations with As in concentrations, while V forms a negative trend. Contour maps demonstrate that As, Zn, Rb, Fe, Ti, Cr, and Ni are enriched together near quartz veins, showing similar elemental behaviors. In-situ analysis using portable SWIR analyzer represents that schist and gneiss contain mica, illite, chlorite, sericite, amphibole, and epidote, while illite, sericite, gypsum, and mica are present in the altered rocks contacted with quartz veins. In contour maps, chlorite occurs mostly in host rocks, while sericite is concentrated near quartz veins. These results are similar to those of previous studies for element dispersion and hydrothermal alteration, and support the possibility for application of in-situ analysis on the exploration of orogenic gold deposit.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1305-1318
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• 2007

On a global scale agriculture and in particular enteric fermentation in ruminants is reported to produce about one fourth (21 to 25%) of the total anthropogenic emissions of methane ($CH_4$). Methane is produced during the anaerobic fermentation of hydrolyzed dietary carbohydrates in the rumen and represents an energy loss to the host besides contributing to emissions of greenhouse gases into the environment. However, there appears to be uncertainty in the $CH_4$ estimation from livestock due to the limited availability of data to document the variability at the farm level and also due to the significant impact of diet on the enteric $CH_4$ production. The methane mitigation strategies require robust prediction of emissions from rumen. There are many methods available which would be suitable for measuring $CH_4$ produced from the various stages of animal production. However, several factors need to be considered in order to select the most appropriate technique like the cost, level of accuracy required and the scale and design of the experiments to be undertaken. Selection of any technique depends on the accuracy as each one has its advantages and disadvantages. Screening of mitigation strategies may be evaluated using individual animal before large-scale trials on groups of animals are carried out. In this review various methods for the estimation of methane production from ruminants as well as for the determination of methane production potential of ruminant feeds are discussed. The advantages and disadvantages of the methods starting from respiration chamber, ventilated hood, facemask, sulphur hexafluoride ($SF_6$) tracer technique, prediction equations and meteorological methods to in vitro methods are detailed.

• Journal of Korea Multimedia Society
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• v.16 no.8
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• pp.943-953
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• 2013

By the enormous increase in mobile nodes and diverse service requests on wireless networks, wireless mesh network(WMN) takes an interest as the solution for such requests. However, lots of issues which should be solved to deploy WMN are still remained. In the network layer, the performance improvement of routing protocols is the major issue of nowadays researches. WMN can be easily deployed by use of protocols for mobile ad-hoc networks(MANET) because it is much similar with MANET in multi-hop wireless routing and which node plays as host and router concurrently. Unfortunately, most routing protocols for MANET have drawbacks such as large traffic overhead and long delay time for route discovery due to the network extension. They are major factors of performance degradation of WMN and most researches are focused on them. In this paper, domain-based AODV which is amended AODV to be applied in hybrid WMN is proposed. The proposed scheme divides a hybrid WMN as several domains and performs route discovery by header layer domain. Therefore it can reduce the distance for route discovery as much as average hop count between domain header and member nodes. From the simulation, domain-based AODV was showed slowly increasing delay time due to the network extension.

• Tuberculosis and Respiratory Diseases
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• v.74 no.2
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• pp.63-69
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• 2013

Background: Aiming to improve outcome of lung transplantation (LTx) patients, we reviewed risk factors and treatment practices for the LTx recipients who experienced respiratory infection in the late post-LTx period (>1 month after LTx). Methods: We analyzed the clinical data of 48 recipients and donors from 61 LTx, who experienced late respiratory infections. Late respiratory infections were classified according to the etiology, time of occurrence, and frequency of donor-to-host transmission or colonization of the recipient prior to transplantation. Results: During the period of observation, 42 episodes of respiratory infections occurred. The organisms most frequently involved were gram (-) bacteria: Acinetobacter baumannii (n=13, 31.0%), Pseudomonas aeruginosa (n=7, 16.7%), and Klebsiella pneumoniae (n=4, 10.0%). Among the 42 episodes recorded, 14 occurred in the late post-LTx period. These were bacterial (n=6, 42.9%), fungal (n=2, 14.3%), viral (n=4, 28.5%), and mycobacterial (n=2, 14.3%) infections. Of 6 bacterial infections, 2 were from multidrug-resistant (MDR) A. baumannii and one from each of MDR P. aeruginosa, extended spectrum ${\beta}$-lactamase (+) K. pneumoniae, methicillin-resistant Staphylococcus aureus and Streptococcus pneumoniae. Infection-related death occurred in 6 of the 14 episodes (43%). Conclusion: Although the frequency of respiratory infection decreased sharply in the late post-LTx period, respiratory infection was still a major cause of mortality. Gram (-) MDR bacteria were the agents most commonly identified in these infections.

• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1844-1854
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• 2017

Trichomonas vaginalis is a pathogen that triggers severe immune responses in hosts. T. vaginalis ${\alpha}$-actinin 2 ($Tv{\alpha}$-actinin 2) has been used to diagnose trichomoniasis. $Tv{\alpha}$-actinin 2 was dissected into three parts; the N-terminal, central, and C-terminal portions of the protein (#1, #2, and #3, respectively). Western blot of these $Tv{\alpha}$-actinin 2 proteins with pooled patients' sera indicated that #2 and #3, but not #1, reacted with those sera. Immunofluorescence assays of two different forms of T. vaginalis (trophozoites and amoeboid forms), using anti-$Tv{\alpha}$- actinin 2 antibodies, showed localization of $Tv{\alpha}$-actinin 2 close to the plasma membranes of the amoeboid form. Fractionation experiments indicated the presence of $Tv{\alpha}$-actinin 2 in cytoplasmic, membrane, and secreted proteins of T. vaginalis. Binding of fluorescence-labeled Trichomonas to vaginal epithelial cells and prostate cells was decreased in the antibody blocking experiment using anti-$Tv{\alpha}$-actinin 2 antibodies. Pretreatment of T. vaginalis with anti-$rTv{\alpha}$-actinin 2 antibodies also resulted in reduction in its cytotoxicity. Flow cytometry, ligand-binding immunoblotting assay, and observation by fluorescence microscopy were used to detect the binding of recombinant $Tv{\alpha}$-actinin 2 to human epithelial cell lines. Specifically, the truncated N-terminal portion of $Tv{\alpha}$-actinin 2, $Tv{\alpha}$-actinin 2 #1, was shown to bind directly to vaginal epithelial cells. These data suggest that ${\alpha}$-actinin 2 is one of the virulence factors responsible for the pathogenesis of T. vaginalis by serving as an adhesin to the host cells.

• Journal of dental hygiene science
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• v.17 no.1
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• pp.81-86
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• 2017

Bacterial infection and smoking are an important risk factors involved in the development and progression of periodontitis. However, the signaling mechanism underlying the host immune response is not fully understood in periodontal lesions. In this study, we determined the expression of janus kinase (JAK)/signal transducer and activator of transcription (STAT) on Porphyromonas gingivalis lipopolysaccharide (LPS)- and nicotine-induced cytotoxicity and the production of inflammatory mediators, using osteoblasts. The cells were cultured with 5 mM nicotine in the presence of $1{\mu}g/ml$ LPS. Cell viability was determined using MTT assay. The role of JAK on inflammatory mediator expression and production, and the regulatory mechanisms involved were assessed via enzyme-linked immunosorbent assay, reverse transcription-polymerase chain reaction, and Western blot analysis. LPS- and nicotine synergistically induced the production of cyclooxgenase-2 (COX-2) and prostaglandin $E_2$ ($PGE_2$) and increased the protein expression of JAK/STAT. Treatment with an JAK inhibitor blocked the production of COX-2 and $PGE_2$ as well as the expression of pro-inflammatory cytokines, such as tumor necrosis factor-${\alpha}$, interleukin-$1{\beta}$ ($IL-1{\beta}$), and IL-6 in LPS- and nicotine-stimulated osteoblasts. These results suggest that JAK/STAT is closely related to the LPS- and nicotine-induced inflammatory effects and is likely to regulate the immune response in periodontal disease associated with dental plaque and smoking.

• Journal of Korean Medical classics
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• v.30 no.1
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• pp.111-133
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• 2017

Objectives : Dryness pathogen, which is one of six pathogenic factors, causes dryness diseases. Currently, the theory on dryness disease is composed of external dryness and internal dryness. External dryness, in turn, is composed of cool dryness and warm dryness. However, these categorizations and their symptoms bear ambiguity for many reasons. Therefore, this paper aims to review various texts in order to study the special features of dryness pathogen and dryness disease. Methods : Texts that deal with dryness pathogen and dryness disease were studied. Most texts are comprised of dissertations and historical medical texts, therefore, CNKI and The Sikuquanshu's databases, and Traditional Chinese Medical(TCM) book webdatabases were utilized. Materials are listed in chronological order, and their main points regarding dryness pathogen and dryness disease are compared. Results & Conclusions : It is difficult to accept the assertion that dryness pathogen does not lead to external dryness. Dryness does not have the elements of chill and fever in itself. Dryness's elements of chill and fever are determined in the ways they combine with each individual element. Moreover, the symptoms of chill and fever on dryness disease are subject to the host's body type. External dryness and internal dryness cannot be discussed within an identical premise. Whereas the dryness in external dryness signifies the cause of a disease, the dryness in internal dryness is the consequence of a disease. In other words, internal dryness revolves around cause of disease and external dryness revolves around the mechanic of disease. It's difficult to determine whether these diseases are caused by dryness or wetness in Autumn. There is an understanding which integrates these together through the Yunqi theory, but it is imperfect.

• Journal of Periodontal and Implant Science
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• v.29 no.1
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• pp.31-40
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• 1999

Many factors may affect periodontal changes during the physiologic conditions of woman(e.g. puberty, menstrual cycle, pregnancy, menopause). Recently many research has focused on the immunological changes of host, but the exact mechanism is not clear. Collagen is a major constituent of periodontium, and collagenase specifically digests the collagen and plays a role in destruction of periodontal tissue. So, I suppose that it participates with the cytokines in the inflammation of gingiva and vascular response during the changes of female sex hormones. Because there are some evidences of the existence of the receptors of estrogen and progesterone in the gingiva, it may be a target tissue of female sex hormones. In this experiment, gingival fibroblast and periodontal ligament cell were cultured in the presence of various concentrations of estrogen or progesterone corresponding to the menstrual cycle and pregnancy. Collagenase activity of the supernatant of culture media was determined by Spectrophotometric collagenase assay. The enzyme activity was calculated by the % decrease of the coated collagen. 1. The estrogen at both concentrations had no effect on the activity of collagenase of the gingival fibroblast. 2. The progesterone had some effect on the collagenase activity of the gingival fibroblast at low and high concentration of menstrual cycle, and elevated the enzyme activity at all range of pregnancy concentrations. 3. In periodontal ligament cells, estrogen elevated the enzyme activity at the early pregnancy concentration and progesterone elevated at the concentration just before menstruation. In this experiment, pregesterone elevated the collagenase activity of gingival fibroblast and periodontal ligament cells. But the mechanism of the up-regulation of the enzyme activity was not confirmed. The more experiments of direct effect of progesterone on gingival at the molecular level(e.g. northern blot analysis) can reveal the exact mechanism.

• Korean Journal of Veterinary Service
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• v.21 no.1
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• pp.97-104
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• 1998

Fugi are eukaryotic, nonphotosynthetic, filamentous or unicellular organisms, most of which grow on nonliving materials as saphrophytes. The majority are therefore opportunistic pathogens and predisposing factors often contribute to the establishment of fungal infection. These include an alteration in the normal flora of the host by prolonged administration of antibiotics, immunosup-pression, concurrent infections, damage to the skin or mucous membranes, constantly moist areas of skin or the exposure to a large infective dose, and as with fungal spores. Fungi may cause a variety of diseases which may be due directly to fungal invasion of tissue or more often to the ingestion of toxins produces by fungi in growing, standing or stored grains and other animals feeds. In this experiment, contaminated fugi were isolated and identified from animal feedstuffs such as Korean cattle, milking cows, pigs and chickens. Twelve genues were isolated from animal feeds, they are 9 from Korean cattle and milking cows feeds, 6 from pigs feeds, and 10 from chickens feeds. Among them, most frequently encountered species was Yeast(56 strains), followed by Fusarium sp(41 strains), Aspergillus sp(20 strains), each of Micorsporum sp and Trichophyton sp(17 strains), Penicilium sp(12 strains), in order. And also minority was isolated as Candide sp(4 strains), Trichoderma sp(3 strains), each of Epidermophytom sp and Absida sp(2 strains), and each of Sporothrix sp and Maduromyces sp(1 strain). Among the Aspergillus sp 20 isolates, A flavus(5 strains), A nidulans(4 strains), A fumigatus(3 strains), A glucans(3 strains), A niger(3 strains) and A terreus(2 strains) were identified.