• Tuberculosis and Respiratory Diseases
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• 제44권3호
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• pp.470-478
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• 1997

연구배경 : 세포내 병원균(intracellular pathogen)으로 감염초기에 단핵식세포(mononuclear phagocytes)에 탐식되는데, 독성(virulent) 결핵균주(Erdman, H37Rv)가 약독화(attenuated) 균주(H37Ra)보다 탐식이 더 잘 되며, 이러한 현상으로부터 결핵균의 입장에서 보면 단핵식세포에 탐식이 잘되는 것이 생존 및 증식에 유리할 것이라는 의견이 제시되어 왔다. 그리고 난치성 결핵환자에서 분리한 결핵균은 임상적으로 독성이 강하며 대부분에서 다제내성을 보이므로, 약제내성 결핵균여 감수성균에 비해 독성이 강하다는 가정하에 약제내성 결핵균이 감수성균에 비해 단핵식세포에 탐식이 더 잘 되는지, 그리고 난치성 결핵환자에서 분리한 단핵식세포가 정상인에 비해 결핵균을 더 잘 탐식하는지 알아보고자 하였다. 방 법 : 약제내성의 정도에 따라 모든약제에 감수성인 결핵균, Isoniazid와 Rifampicin을 포함한 일부 약제에 내성인 결핵균, 모든 약제에 내성인 결핵균을 각각 $70^{\circ}C$에서 1시간 가열하여 사멸시킨 뒤 부유액을 만들어 10명의 난치성 결핵환자와 12명의 정상인에서 분리한 말초혈액탄핵구 배양액에 첨가하여 탐식시킨 뒤 단핵구의 결핵균을 탐식율을 관찰하였다. 결 과 : 약제내성 결핵균이 감수성균에 비하여 말초혈액단핵구에 탐식이 더 잘되었으며(정상 대조군에서 분리한 말초혈액단핵구의 결핵균 탐식율 : 모든약제 감수성균 : $32.3{\pm}2.9%$, 모든약제 내성균 : $49.6{\pm}3.4%$, p = 0.0022, 난치성 결핵환자군에서 분리한 말초혈액단핵구의 결핵균 탐식율 : 모든약제 감수성균 : $34.9{\pm}3.6%$, 모든약제 내성균 : $50.7{\pm}4.5%$, p = 0.0069), 난치성 결핵환자와 정상인에서 분리한 말초혈액단핵구 사이의 결핵균의 탐식능에는 차이가 없었다. 결 론 : 약제 내성균이 감수성균보다 단핵식세포에 탐식이 더 잘 되며, 숙주 요인은 결핵균의 탐식의 차이에 영향을 미치지 않는 것으로 보인다.

• 자원환경지질
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• 제52권4호
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• pp.259-274
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• 2019

휴대용 X선 형광분석기(XRF)와 단파장 적외선 분광분석기(SWIR)를 이용하여 조산형 금광상인 삼광광상의 열수유체와 모암의 반응에 의한 원소분산과 모암변질 양상을 파악하고 이를 통해 광상탐사인자를 추정하고자 하였다. 이를 위해 편암 및 편마암, 그리고 석영맥과의 접촉변질대 등으로 구성된 삼광광상 본항갱에서 일정간격으로 804개 지점에 대해 총 4,824회 측정하였고, 이 결과를 XRF 및 ICP 정량분석결과와 비교하였다. 회귀분석결과 현장측정 주원소 결정계수는 0.88, V을 제외한 미량원소는 0.56를 보인다. 일부 시료를 연마한 후 측정한 결과 주원소 결정계수는 0.97, 미량원소는 0.65로서 현장측정결과보다 높게 나타난다. 석영맥 변질대 분석결과 As는 Fe, Zn, Rb와 양의 상관관계를 보이며, V과는 음의 관계를 나타낸다. 컨투어맵 분석결과에서 As는 Zn, Rb, Fe, Ti, Cr, Ni 등과 함께 석영맥 부근에서 함량이 증가하는 것으로 나타나 상호 유사한 경향성을 보인다. 휴대용 SWIR을 이용한 현장측정결과 편암 및 편마암에는 운모, 일라이트, 녹니석, 견운모, 각섬석, 녹염석 등의 조합을 보이고, 석영맥과 접한 변질대에서는 일라이트, 견운모, 석고 및 운모 등이 검출된다. 컨투어맵 작성결과 녹니석은 대부분 모암에서 산출되는 반면, 견운모는 석영맥 부근에서 높게 나타난다. 휴대용 분석기기를 이용한 이러한 결과는 기존의 원소분산 및 열수변질 연구결과와 유사하며 조산형 금광상 탐사에 효과적으로 사용가능할 것으로 여겨진다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권8호
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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.

• 한국멀티미디어학회논문지
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• 제16권8호
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• pp.943-953
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• 2013

이동 노드의 증가와 무선 네트워크 기반의 서비스 요구의 다양화로 무선 메시 네트워크(WMN)가 많은 관심을 받고 있다. 하지만 WMN를 실제 서비스하기 위해서는 아직 해결해야 할 과제가 많이 남아있다. 네트워크 계층에서는 라우팅 프로토콜의 성능개선이 주요 해결 과제이다. 무선 네트워크에서의 다중 홉라우팅과 노드가 호스트와 라우터의 역할을 동시에 수행한다는 관점에서 WMN은 모바일 에드혹 네트워크(MANET)와 유사하여 MANET의 라우팅 프로토콜의 사용을 통해 쉽게 구축이 가능하다. 하지만 MANET의 라우팅 프로토콜은 대부분이 네트워크의 규모가 커지면 전송 오버헤드나 지연시간이 증가한다는 단점이 있다. 이는 WMN에 의한 무선 네트워크의 확장에 있어 성능저하의 원인이며 이를 개선하기 위하여 많은 연구들이 진행되었다. 본 논문에서는 AODV를 계층형으로 개선하여 혼합형 WMN에 적용하기 위한 방안으로써 도메인 기반 AODV에 대하여 제안한다. 제안된 방안은 AODV의 요구형 경로 결정을 도메인 단위로 구분 수행함으로써 종단 간 수행되는 평균 경로 결정 거리를 줄여 네트워크의 확장성 문제를 해결한다. 제안된 방안의 시뮬레이션 결과 AODV에 비하여 네트워크의 확장에 대한 지연시간의 증가가 완만하였다.

• Tuberculosis and Respiratory Diseases
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• 제74권2호
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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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• 제27권10호
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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.

• 치위생과학회지
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• 제17권1호
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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.

• 대한한의학원전학회지
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• 제30권1호
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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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• 제29권1호
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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.

• 한국동물위생학회지
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• 제21권1호
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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.