• Journal of Microbiology and Biotechnology
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• 제20권10호
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• pp.1450-1456
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• 2010

Accurate and rapid diagnosis of Pandemic Influenza A/H1N1 2009 virus (H1N1 2009) infection is important for the prevention and control of influenza epidemics and the timely initiation of antiviral treatment. This study was conducted to evaluate the performance of several diagnostic tools for the detection of H1N1 2009. Flocked nasopharyngeal swabs were collected from 254 outpatients of suspected H1N1 2009 during October 2009. This study analyzed the performances of the RealTime Ready Inf A/H1N1 Detection Set (Roche), Influenza A (H1N1) Real-Time Detection Kit (Bionote), Seeplex Influenza A/B OneStep Typing Set [Seeplex Reverse Transcriptase PCR (RT-PCR)], BinaxNow Influenza A & B Test Kit [Binax Rapid Antigen Test (RAT)], and SD BIOLINE Influenza Ag kit (SD RAT). Roche and Bionote real-time RT-PCR showed identical results for the H1N1 2009 hemagglutinin gene. Compared with real-time RT-PCR, the sensitivities and specificities were 83.7% and 100% for Seeplex RT-PCR, 64.5% and 94.7% for Binax RAT, and 69.5% and 100% for SD RAT. The sensitivities of Seeplex RT-PCR, Binax RAT, and SD RAT in patients aged over 21 years were 73.7%, 47.4%, and 57.9%, respectively. The sensitivities of Seeplex RT-PCR, Binax RAT, and SD RAT on the day of initial symptoms were mostly lower (68.8%, 56.3%, and 31.3%, respectively). In conclusion, multiplex RT-PCR and RAT for the detection of H1N1 2009 were significantly less sensitive than real-time RT-PCR. Moreover, a negative RAT may require more sensitive confirmatory assays, because it cannot be ruled out from influenza infection.

• 한국환경생태학회지
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• 제31권1호
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• pp.30-41
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• 2017

국내에서 포유류는 축산학, 수의학, 실험동물학, 생태학, 유전학 등 다양한 분야에서 활발하게 연구되고 있으며, 최근 생물다양성의 중요성이 강조되면서 이들의 보전 및 관리는 국민적으로도 많은 관심을 받고 있다. 하지만 전문 연구와 국민 관심의 증가에도 불구하고 국내 포유류 연구동향을 파악한 사례는 아직까지 찾아보기 힘들다. 이 연구는 국내 포유류의 연구동향을 파악하여 향후 세부연구영역의 계획과 관련 정책 제시를 위한 기초자료 제공을 목표로 하였다. 2015년까지 국내에서 발행된 포유류 학술논문 392편을 분석 대상으로 하였으며, 최근 각광받는 연구영역을 파악하기 위해 텍스트마이닝과 동시출현단어 분석을 이용하였다. 그 결과, 국내 포유류 연구논문 발행 수는 점차 증가하였으며, 연구대상 종 역시 점차 다양해진 것으로 나타났다. 텍스트마이닝과 동시출현단어 분석을 통해 파악된 주된 포유류 연구영역은 (1)진화/계통/유전학, (2)환경/생태학, (3)발생/생식/세포생물학, (4)기생충/수의학, (5)설치류/기생충학, (6)세균/바이러스학, (7)해부/세포생물/실험동물학, (8)형태/해부수의학, (9)축산학, (10)해양포유류학, (11)익수목 연구 등 11개로 구분되었다. 환경/생태학 연구는 11개 연구영역 중에서 최근 가장 활발하였으며, 과거에 비해 연구비율이 급격히 증가한 분야로 나타났다. 환경/생태학 연구분야는 생물다양성 보전의 핵심으로, 최근 생물다양성의 중요성이 강조됨에 따라 국내 서식 포유류의 생태연구에 대한 연구자들의 관심 역시 더욱 증가한 것으로 보인다. 이 연구결과가 미래 국내 포유류 연구의 계획과 관련 정책 수립을 위한 기초자료로 유용하게 활용되기를 희망한다.

• 대한의생명과학회지
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• 제5권2호
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• pp.147-153
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• 1999

본 연구는 흰쥐에 호르텐스극구흡충 피낭유충을 흰쥐에게 실험적으로 감염시켜 감염기간에 따른 항체 생산 유무를 규명하였다. 감염 흰쥐의 혈청을 기간별로 채취하여 IgG및 IgM 항체가를 ELISA 법으로 측정하였으며, 또한 이의 진단적 이용가치를 평가하고 이들에 대한 상관성을 검토한 결과는 다음과 같다. 즉, 기간별 특이 IgG 항체가는 0.13$\pm$0.014 (mean$\pm$S.D.)에서 0.4803$\pm$0.073까지의 분포를 보였으며 감염 제 28일에 최고치 (0.4803$\pm$0.073)를 보였다 (p<0.05). 호르텐스극구흡충에 감염된 백서를 통해 매주 얻은 특이 IgM 항체가는 0.16$\pm$0.034 (mean$\pm$S.D.)에서 0.4093$\pm$0.084까지의 분포를 보였으며 감염 제 7일에 증가하여 감염 제 14일에 최고치 (0.4093$\pm$0.084)를 보였다(p<0.05). 이상의 결과를 종합할 때 호르텐스극구흡충 감염시 흰쥐 혈청의 IgM은 감염 초기에 급속한 증가를 보였으나 IgG는 감염 이후 계속 증가하는 경향을 보였다.

• 생명과학회지
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• 제20권5호
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• pp.697-702
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• 2010

2007년 전국 10개의 일반 양돈장에서 다양한 일령의 돼지 578두를 채혈하여 Rose Bengal test 진단액으로 스크리닝을 하고, 양성 혈청에 대해서는 시험관응집반응과 C-ELISA를 적용하여 브루셀라병 항체 분포도 양상과 브루셀라 교차반응 유발균의 분리를 시도하여 다음과 같은 결론을 얻었다. 돼지에서 브루셀라병 Rose Bengal 스크리닝 결과, 10주령 미만(양성률; 14.6%, 95% CI; 10.1-19.1)자돈보다 10주령에서 17주령 미만(양성률; 31.3%, 95% CI; 22.8-39.8)과 17주령 이상(양성률; 30.4%, 95% CI; 34.3-36.4)의 돼지에서 양성률이 유의성 있게 높았다(p<0.05). 따라서 검사돈 중 139두 (24.0%)에서 Rose Bengal test 양성반응이 나타났다. 양돈장별 Rose Bengal test 양성률 조사에서 6개 양돈장이 10% 미만의 양성률을 보였고, 2개 양돈장에서는 70% 이상의 높은 양성률이 관찰되었다. Rose Bengal test 양성 혈청 139건을 시험관응집반응과 C-ELISA에 적용한 결과, 시험관응집반응에서 100배 이상의 양성이 48건(34.5%)이었으나 C-ELISA에서는 전 두수 음성으로 나타나 돼지 혈청에 대해서는 시험관응집반응 성적과 C-ELISA 성적에 많은 차이가 있었다. 시험관응집반응에서 높은 항체가를 보인 돼지의 직장 swab 시료(n=26)에서 브루셀라 균과 교차반응을 유발하는 균종에 대해 균분리를 실시한 결과 E. coli O157:H7, Salmonella N group은 분리되지 않았으나 Y. enterocolitica O:9은 7건(26.9%)이 분리되었다.

• Applied Microscopy
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• 제37권2호
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• pp.65-72
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• 2007

참붕어의 난자형성과정과 수정란 난막의 미세구조를 광학현미경과 전자현미경으로 관찰한 결과는 다음과 같다. 참붕어에서 난원세포의 세포질은 호염기성이었고 핵막 내에 많은 인들이 분포하고 있었다. 제1난모세포의 경우 난황포가 단지 난세포 가장자리에만 배열되어 있었고 난막의 형성은 관찰되지 않았다. 제2난모세포에서는 난막이 형성되었고 제1난모세포에 비해서 난황포가 점점 핵쪽으로 증식된 경향을 보였다. 발생이 진행됨에 따라서 호염기성 물질들은 점점 감소하는 경향을 보였고 후에 난막주위에만 국한적으로 분포하였으며, 난막의 두께와 난자의 크기는 점점 증가되었다. 또한 성숙란으로 발생이 진행되면서 난황포들은 난황괴로 변화되었다. 참붕어의 수정란은 타원형으로 부착성이었으며 동물극쪽에서 난문이 관찰되었다. 수정란의 난막은 모두 3층으로, 부착성인 외층, 전자밀도가 서로 다른 6층상구조를 가진 중층 및 전자밀도가 높은 내층으로 구성되어 있었으며 난막표면은 부착성 섬유상 구조물로 덮여 있었다. 이상과 같이 참붕어의 난자형성과정은 생식세포의 크기 증가, 난황의 형성과 축적 및 세포질의 호염기성물질 감소로 될 수 있으며 수정란 난막의 미세구조적 특징들은 경골어류의 계통분류학에서 분류형질도 이용될 수 있을 것으로 생각된다.

• The Korean Journal of Physiology and Pharmacology
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• 제16권3호
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• pp.167-174
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• 2012

Natural killer (NK) cells provide one of the initial barriers of cellular host defense against pathogens, in particular intracellular pathogens. Because bone marrow-derived hematopoietic stem cells (HSCs), lymphoid protenitors, can give rise to NK cells, NK ontogeny has been considered to be exclusively lymphoid. Here, we show that porcine c-$kit^+$ bone marrow cells (c-$kit^+$ BM cells) develop into NK cells in vitro in the presence of various cytokines [interleukin (IL)-2, IL-7, IL-15, IL-21, stem cell factor (SCF), and fms-like tyrosine kinase-3 ligand (FLT3L)]. Adding hydrocortisone (HDC) and stromal cells greatly increases the frequency of c-$kit^+$ BM cells that give rise to $CD2^+CD8^+$ NK cells. Also, intracellular levels of perforin, granzyme B, and NKG2D were determined by RT-PCR and western blotting analysis. It was found that of perforin, granzyme B, and NKG2D levels significantly were increased in cytokine-stimulated c-$kit^+$ BM cells than those of controls. And, we compared the ability of the cytotoxicity of $CD2^+CD8^+$ NK cells differentiated by cytokines from c-$kit^+$ BM cells against K562 target cells for 28 days. Cytokines-induced NK cells as effector cells were incubated with K562 cells as target in a ratio of 100 : 1 for 4 h once a week. In results, $CD2^+CD8^+$ NK cells induced by cytokines and stromal cells showed a significantly increased cytotoxicity 21 days later. Whereas, our results indicated that c-$kit^+$ BM cells not pretreated with cytokines have lower levels of cytotoxicity. Taken together, this study suggests that cytokines-induced NK cells from porcine c-$kit^+$ BM cells may be used as adoptive transfer therapy if the known obstacles to xenografting (e.g. immune and non-immune problems) were overcome in the future.

• Biomolecules & Therapeutics
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• 제29권6호
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• pp.685-696
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• 2021

In this study, we investigated the inhibitory effect of 5-aminolevulinic acid (ALA), a heme precursor, on inflammatory and oxidative stress activated by lipopolysaccharide (LPS) in RAW 264.7 macrophages by estimating nitric oxide (NO), prostaglandin E2 (PGE2), cytokines, and reactive oxygen species (ROS). We also evaluated the molecular mechanisms through analysis of the expression of their regulatory genes, and further evaluated the anti-inflammatory and antioxidant efficacy of ALA against LPS in the zebrafish model. Our results indicated that ALA treatment significantly attenuated the LPS-induced release of pro-inflammatory mediators including NO and PGE2, which was associated with decreased inducible NO synthase and cyclooxygenase-2 expression. ALA also inhibited the LPS-induced expression of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, reducing their extracellular secretion. Additionally, ALA abolished ROS generation, improved the mitochondrial mass, and enhanced the expression of heme oxygenase-1 (HO-1) and the activation of nuclear translocation of nuclear factor-E2-related factor 2 (Nrf2) in LPS-stimulated RAW 264.7 macrophages. However, zinc protoporphyrin, a specific inhibitor of HO-1, reversed the ALA-mediated inhibition of pro-inflammatory cytokines production and activation of mitochondrial function in LPS-treated RAW 264.7 macrophages. Furthermore, ALA significantly abolished the expression of LPS-induced pro-inflammatory mediators and cytokines, and showed strong protective effects against NO and ROS production in zebrafish larvae. In conclusion, our findings suggest that ALA exerts LPS-induced anti-inflammatory and antioxidant effects by upregulating the Nrf2/HO-1 signaling pathway, and that ALA can be a potential functional agent to prevent inflammatory and oxidative damage.

• Parasites, Hosts and Diseases
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• 제61권3호
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• pp.272-281
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• 2023

Chigger mites are the vector of scrub typhus. This study estimates the infestation status and ecological characteristics of chiggers on the chestnut white-bellied rat Niviventer fulvescens in Southwest China between 2001 and 2019. Chiggers were identified under the microscope, and infestation indices were calculated. The Preston's log-normal model was used to fit the curve of species abundance distribution. A total of 6,557 chiggers were collected in 136 of 342 N. fulvescens rats, showing high overall infestation indices (prevalence=39.8%, mean abundance=19.2, mean intensity=48.2) and high species diversity (S=100, H'=3.0). Leptotrombidium cangjiangense, Neotrombicula japonica, and Ascoschoengastia sifanga were the three dominant chigger species (constituent ratio=42.9%; 2,736/6,384) and exhibited an aggregated distribution among different rat individuals. We identified 100 chigger species, with 3 of them (Leptotrombidium scutellare, Leptotrombidium wenense, and Leptotrombidium deliense) as the main vectors of scrub typhus in China and nine species as potential vectors of this disease. Disease vector occurrence on N. fulvescens may increase the risk of spreading scrub typhus from rats to humans. Chigger infestation on N. fulvescens varied significantly in different environments. The species abundance distribution showed a log-normal distribution pattern. The estimated number of chigger species on N. fulvescens was 126 species.

• Parasites, Hosts and Diseases
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• 제61권1호
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• pp.60-71
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• 2023

Cockroaches can cause allergic sensitization in humans via contact with their feces or frass. Antibiotics can affect concentration of major allergen and total bacteria production in German cockroaches (Blattella germanica). This study examined the ability of antibiotic-treated German cockroaches to induce allergic airway inflammation and the effect of antibiotics on their lipopolysaccharide and Bla g1, 2, and 5 expression levels. Specifically, we measured the ability of German cockroach extract (with or without prior antibiotic exposure) to induce allergic inflammation in human bronchial epithelial cells and a mouse model of asthma. Bacterial 16S rRNA and lipopolysaccharide levels were lower in ampicillin-treated cockroaches than in the control group. The Bla g1, Bla g2, and Bla g5 expression in ampicillin-treated cockroaches decreased at both the protein and RNA levels. In human bronchial epithelial cell lines BEAS-2B exposed to the ampicillin-treated extract, expression levels of interleukin-6 and interleukin-8 were lower than that in the control group. The total cell count and eosinophil count in bronchoalveolar lavage fluid was also lower in mice exposed to the ampicillin-treated extract than in those exposed to normal cockroach extract. Mouse lung histopathology showed reduced immune cell infiltration and mucus production in the ampicillin group. Our results showed that ampicillin treatment reduced the symbiont bacterial population and major allergen levels in German cockroaches, leading to reduced airway inflammation in mice. These results can facilitate the preparation of protein extracts for immunotherapy or diagnostics applications.

• Journal of Microbiology and Biotechnology
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• 제33권5호
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• pp.591-599
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• 2023

Fisetin is a bioactive flavonol molecule and has been shown to have antioxidant potential, but its efficacy has not been fully validated. The aim of the present study was to investigate the protective efficacy of fisetin on C2C12 murine myoblastjdusts under hydrogen peroxide (H₂O₂)-induced oxidative damage. The results revealed that fisetin significantly weakened H₂O₂-induced cell viability inhibition and DNA damage while blocking reactive oxygen species (ROS) generation. Fisetin also significantly alleviated cell cycle arrest by H₂O₂ treatment through by reversing the upregulation of p21WAF1/CIP1 expression and the downregulation of cyclin A and B levels. In addition, fisetin significantly blocked apoptosis induced by H₂O₂ through increasing the Bcl-2/Bax ratio and attenuating mitochondrial damage, which was accompanied by inactivation of caspase-3 and suppression of poly(ADP-ribose) polymerase cleavage. Furthermore, fisetin-induced nuclear translocation and phosphorylation of Nrf2 were related to the increased expression and activation of heme oxygenase-1 (HO-1) in H₂O₂-stimulated C2C12 myoblasts. However, the protective efficacy of fisetin on H₂O₂-mediated cytotoxicity, including cell cycle arrest, apoptosis and mitochondrial dysfunction, were greatly offset when HO-1 activity was artificially inhibited. Therefore, our results indicate that fisetin as an Nrf2 activator effectively abrogated oxidative stress-mediated damage in C2C12 myoblasts.