• Asian-Australasian Journal of Animal Sciences
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• 제29권8호
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• pp.1188-1196
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• 2016

This study evaluated the risk of Clostridium perfringens (C. perfringens) foodborne illness from natural and processed cheeses. Microbial risk assessment in this study was conducted according to four steps: hazard identification, hazard characterization, exposure assessment, and risk characterization. The hazard identification of C. perfringens on cheese was identified through literature, and dose response models were utilized for hazard characterization of the pathogen. For exposure assessment, the prevalence of C. perfringens, storage temperatures, storage time, and annual amounts of cheese consumption were surveyed. Eventually, a simulation model was developed using the collected data and the simulation result was used to estimate the probability of C. perfringens foodborne illness by cheese consumption with @RISK. C. perfringens was determined to be low risk on cheese based on hazard identification, and the exponential model ($r=1.82{\times}10^{-11}$) was deemed appropriate for hazard characterization. Annual amounts of natural and processed cheese consumption were $12.40{\pm}19.43g$ and $19.46{\pm}14.39g$, respectively. Since the contamination levels of C. perfringens on natural (0.30 Log CFU/g) and processed cheeses (0.45 Log CFU/g) were below the detection limit, the initial contamination levels of natural and processed cheeses were estimated by beta distribution (${\alpha}1=1$, ${\alpha}2=91$; ${\alpha}1=1$, ${\alpha}2=309$)${\times}$uniform distribution (a = 0, b = 2; a = 0, b = 2.8) to be -2.35 and -2.73 Log CFU/g, respectively. Moreover, no growth of C. perfringens was observed for exposure assessment to simulated conditions of distribution and storage. These data were used for risk characterization by a simulation model, and the mean values of the probability of C. perfringens foodborne illness by cheese consumption per person per day for natural and processed cheeses were $9.57{\times}10^{-14}$ and $3.58{\times}10^{-14}$, respectively. These results indicate that probability of C. perfringens foodborne illness by consumption cheese is low, and it can be used to establish microbial criteria for C. perfringens on natural and processed cheeses.

• 한국산림과학회지
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• 제87권1호
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• pp.50-56
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• 1998

오존에 약(弱)하거나 저항성(抵抗性)을 가지는 포플러 개체(個體)를 선발(選拔)하기 위해서 36개의 잡종(雜種)포플러 클론을 오존에 노출(露出)시켰다. Open-top chamber를 이용(利用)하여 하루에 6-8시간, 3개월 동안 90-115ppb의 농도(濃度)로 오존을 노출시켰다. 수고(樹高), 직경(直徑), 엽수(葉數), 물질생산량(物質生産量), root/shoot비율(比率), 낙엽률(落葉率), 기공반응(氣孔反應) 조사(調査)하였다. 수고, 직경, 엽수, 물질생산량, root/shoot비율, 기공 conductance는 오존 때문에 감소(減少)하였고, 낙엽률은 증가(增加)하였다. 이 연구에서는 기공 conductance와 물질생산량과의 관계(關係)는 아주 낮게 나타났다. 오존환경(環境)에 대해서 저항성을 갖는 것은 기공(氣孔)의 개폐(開閉)와 항상(恒常) 관계(關係)가 있는 것은 아니라고 사료(思料)되며, 아마도 생화학적(生化學的)이고 생리적(生理的)인 다른 요인(要因)에 대(對)한 연구(硏究)가 포플러 클론이 갖는 저항성을 이해(理解)하는데 도움이 될 것이다.

• Journal of Applied Biological Chemistry
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• 제49권4호
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• pp.148-153
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• 2006

While the underlying molecular mechanism remains to be elucidated, recent studies suggest that polar auxin transport is a key controlling factor in triggering differential growth responses to gravity. Identification of regulatory components in auxin-mediated differential cell expansion would improve our understanding of the gravitropic response. In this study, we identify a mutant designated aux1-like(later changed to aux1), an allele of the aux1 mutant that exhibits a severely disrupted root gravitropic response, but no defects in developmental processes. In Arabidopsis, AUX1 encodes an auxin influx carrier. Since in-depth characterization of the gravitropic response caused by mutations in this gene has been performed previously, we focused on identifying the downstream genes that were differentially expressed compared to wild-type plants. Consistent with the mutant phenotype, the transcription of the auxin-responsive genes IAA17 and GH3 were altered in aux1 plants treated with IAA, 2, 4-D and NAA. In addition, we identified two expansin genes EXP10 and EXPL3 that exhibited different expression in wild-type and mutant plants.

• The Plant Pathology Journal
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• 제23권3호
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• pp.193-202
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• 2007

Typical susceptible symptoms of the bacterial pustule disease caused by Xanthomonas axonopodis pv. glycines are pustule and chlorotic haloes that usually occur in leaves of Glycine max plants. The soybean genotype 'PI96188' showed an atypical response to all tested races X. axonopodis pv. glycines, accompanied with necrosis without chlorotic haloes on the underside of the necrotic symptoms. X. axonopodis pv. glycines 8ra grew to levels from 10 to 100 fold lower on PI96188 than on susceptible cultivar Jinjoo1, but 10-fold higher than on the resistant cultivar CNS. The chlorophyll content in PI96188 leaves remained unchanged until 12 days after bacterial infection. Ultrastructural observation showed that the infected leaf cells of PI96188 had intact normal chloroplasts compared to those of the susceptible cultivar Jinjoo1. Chloroplast degradation or the absence of chloroplasts in cells of the infected tissues was observed in Jinjoo1. Senescence-related ACS7 gene was significantly induced in PI96188 compared to those in Jinjoo1 at 2 days after inoculation. While photosynthesis-related rbcS gene showed the dramatic change in Jinjoo1, this gene was constitutively expressed in PI96188. However, expression of the defense-related genes, such as peroxidase and isoflavone synthase in the infected PI96188 leaves was similar to that in Jinjoo1. Together, these results suggest that the novel necrotic symptom in PI96188 is a kind of resistant response different from a typical hypersensitive response in the resistant genotypes.

• 환경생물
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• 제23권1호
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• pp.21-26
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• 2005

Cell response to genotoxic agents is complex and involves the participation of different classes of genes including cell cycle control, DNA repair and apoptosis. In this report, we presented a approach to characterize the cellular functions associated with the altered transcript profiles of MCF-7 exposed to low-dose in vitro gamma-irradiation. We used the method of human 2.4 k cDNA microarrays containing apoptosis, cell cycle, chromatin, repair, stress and chromosome genes to analyze the differential gene expression characterization that were displayed by radiation-exposed cell, human breast carcinoma MCF-7 cell line, such as 4 Gy 4 hr, 8 Gy 4 hr, and 8 Gy 12 hr. Among these genes, 66 were up-regulated and 49 were down-regulated. Specific genes were concomitantly induced in the results. Cyclin dependent kinase 4 (Cdk4) is induced for starting the cell cycle. This regulation is required for a DNA damage­induced G1 arrest. In addition to, an apoptotic pathways gene Bcl-w was concomitantly induced. Mismatch repair protein homologue-l (hMLH1), a necessary component of DNA mismatch protein repair (MMR), in G2-M cell cycle checkpoint arrest. The present study provides new information on the molecular mechanism underlying the cell response to genotoxic stress, with relevance to basic and clinical research.

• Plant Biotechnology Reports
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• 제3권3호
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• pp.183-190
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• 2009

Rho-related GTPase of plants (ROP) plays an important role in plant growth and development as a signaling protein. Plant RopGEFs are recently identified ROP activator proteins in Arabidopsis. In this study, we cloned 14 RopGEFs in Arabidopsis and characterized their expression patterns in response to abiotic stresses. Fourteen RopGEF genes were categorized into three groups based on their amino acid homologies and molecular sizes. Most RopGEFs were expressed predominantly in flower but some RopGEFs displayed a tissue-specific expression pattern. RopGEF1, 4, 5, and 11 were expressed in all tissues including root and leaves whereas RopGEF7, 8, 9, and 13 were expressed only in flowers. The transcript levels of 14 RopGEFs were changed significantly depending upon abiotic stresses such as cold, heat, drought and salts. RopGEF5 transcription was up-regulated by salt and drought treatment but down-regulated by heat. RopGEF14 transcript level was also increased by salt but decreased by heat stress. The transcript levels of RopGEF1, 7, 9, and 12 were enhanced in response to heat stress but showed no changes in response to cold stresses. Drought stress activated Group 3 RopGEFs such as RopGEF5 and 7. Taken together, 14 RopGEFs are responding to the abiotic stresses individually or as a group.

• The Korean Journal of Physiology and Pharmacology
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• 제26권2호
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• pp.77-86
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• 2022

The effect of PHAR-DBH-Me, a cannabinoid receptor agonist, on different cardiovascular responses in adult male rats was analyzed. The blood pressure was measured directly and indirectly. The coronary flow was measured by Langendorff preparation, and vasomotor responses induced by PHAR-DBH-Me in aortic rings precontracted with phenylephrine (PHEN) were analyzed. The intravenous injection of the compound PHAR-DBH-Me (0.018-185 ㎍/kg) resulted in decreased blood pressure; maximum effect was observed at the dose of 1,850 ㎍/kg. A concentrationdependent increase in the coronary flow was observed in a Langendorff preparation. In the aortic rings, with and without endothelium, pre-contracted with PHEN (10^-6 M), the addition of PHAR-DBH-Me to the superfusion solution (10^-12-10^-5 M), produced a vasodilator response, which depends on the concentration and presence of the endothelium. L-NAME inhibited these effects. Addition of CB₁ receptor antagonist (AM 251) did not modify the response, while CB₂ receptor antagonist (AM630) decreased the potency of relaxation elicited by PHAR-DBH-Me. Indomethacin shifted the curve concentration-response to the left and produced an increase in the magnitude of the maximum endothelium dependent response to this compound. The maximum effect of PHAR-DBH-Me was observed with the concentration of 10^-5 M. These results show that PHAR-DBH-Me has a concentration-dependent and endothelium-dependent vasodilator effect through CB₂ receptor. This vasodilation is probably mediated by the synthesis/release of NO. On the other hand, it is suggested that PHAR-DBH-Me also induces the release of a vasoconstrictor prostanoid.

• Fisheries and Aquatic Sciences
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• 제25권11호
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• pp.559-571
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• 2022

Galectins, a family of ß-galactoside-binding lectins, have emerged as soluble mediators in infected cells and pattern recognition receptors (PRRs) responsible for evoking and regulating innate immunity. The present study aimed to evaluate the role of galectin-1 in the host immune response of redlip mullet (Liza haematocheilia). We established a cDNA database for redlip mullet, and the cDNA sequence of galectin-1 (LhGal-1) was characterized. In silico analysis was performed, and the spatial and temporal expression patterns in gills and blood in response to lipopolysaccharide polyinosinic:polycytidylic acid, and Lactococcus garvieae were estimated via quantitative real-time PCR. Functional assays were conducted using recombinant protein to investigate carbohydrate binding, bacterial binding, and bacterial agglutination activity. LhGal-1 was composed of 135 amino acids. Conserved motifs (H-NPR, -N- and -W-E-R) within the carbohydrate recognition domain were found in LhGal-1. The tissue distribution revealed that the healthy stomach expressed high levels of LhGal-1. The temporal monitoring of LhGal-1 mRNA expression in the gill and blood showed its significant upregulation in response to immune challenges with different stimulants. rLhGal-1 exhibited binding activity in response to carbohydrates and bacteria. Moreover, the agglutination of rLhGal-1 against Escherichia coli was observed. Collectively, our findings suggest that LhGal-1 may function as a PRR in redlip mullet. Furthermore, LhGal-1 can be considered a significant gene to play a protective role in redlip mullet immune system.

• Korean Journal of Radiology
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• 제25권5호
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• pp.426-437
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• 2024

Objective: Cardiac magnetic resonance (CMR) is a diagnostic tool that provides precise and reproducible information about cardiac structure, function, and tissue characterization, aiding in the monitoring of chemotherapy response in patients with light-chain cardiac amyloidosis (AL-CA). This study aimed to evaluate the feasibility of CMR in monitoring responses to chemotherapy in patients with AL-CA. Materials and Methods: In this prospective study, we enrolled 111 patients with AL-CA (50.5% male; median age, 54 [interquartile range, 49-63] years). Patients underwent longitudinal monitoring using biomarkers and CMR imaging. At follow-up after chemotherapy, patients were categorized into superior and inferior response groups based on their hematological and cardiac laboratory responses to chemotherapy. Changes in CMR findings across therapies and differences between response groups were analyzed. Results: Following chemotherapy (before vs. after), there were significant increases in myocardial T2 (43.6 ± 3.5 ms vs. 44.6 ± 4.1 ms; P = 0.008), recovery in right ventricular (RV) longitudinal strain (median of -9.6% vs. -11.7%; P = 0.031), and decrease in RV extracellular volume fraction (ECV) (median of 53.9% vs. 51.6%; P = 0.048). These changes were more pronounced in the superior-response group. Patients with superior cardiac laboratory response showed significantly greater reductions in RV ECV (-2.9% [interquartile range, -8.7%-1.1%] vs. 1.7% [-5.5%-7.1%]; P = 0.017) and left ventricular ECV (-2.0% [-6.0%-1.3%] vs. 2.0% [-3.0%-5.0%]; P = 0.01) compared with those with inferior response. Conclusion: Cardiac amyloid deposition can regress following chemotherapy in patients with AL-CA, particularly showing more prominent regression, possibly earlier, in the RV. CMR emerges as an effective tool for monitoring associated tissue characteristics and ventricular functional recovery in patients with AL-CA undergoing chemotherapy, thereby supporting its utility in treatment response assessment.

• Archives of Pharmacal Research
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• 제27권4호
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• pp.442-448
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• 2004

Wogonin (5,7-dihydroxy-8-methoxyflavone) is a down-regulator of cyclooxygenase-2 and inducible nitric oxide synthase expression, contributing to anti-inflammatory activity in vivo. For further characterization of modulatory activity on ploinflammatory gene expression in vivo, the effect of wogonin was examined in this experiment using animal models of skin inflammation. By topical application, wogonin inhibited an edematic response as well as ploinflammatory gene expression against contact dermatitis In mice. Wogonin inhibited ear edema ($19.4-22.6\%$) at doses of $50-200\;{\mu}g$/ear and down-regulated interleukin-$1{\beta}$ induction ($23.1\%$) at $200{\mu}g$/ear in phenol-induced simple irritation. Wogonin ($2{\times}50-2{\times}200{\mu}g$/ear) also inhibited edematic response ($51.2-43.9\%$) and down-regulated ploinflammatory gene expression of cyclooxygenase-2, interleukin-$1{\beta}$, interferon-$\gamma$, intercellular adhesion molecule-1 and inducible nitric oxide synthase with some different sensitivity against picryl chloride-induced delayed hypersensitivity reaction. All these results clearly demonstrate that wogonin is a down-regulator of ploinflammatory gene expression in animal models of skin inflammation. Therefore, wogonin may have potential for a new anti-inflammatory agent against skin inflammation.