• 대한의생명과학회지
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• 제24권3호
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• pp.175-182
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• 2018

Aspergillosis is a life-threatening disease in individuals with compromised immune systems. Fungal invasion is a highly critical process during host cellular infection. Several papers have reported that transcription factors are responsible for the infection process. To investigate what transcription factors are involved in the process in an effort to inhibit fungal infection into cells, I checked the surfactant protein family and PU.1 transcription factor levels in A549 cells infected with A. fumigatus conidia. PU.1 and surfactant protein-D levels were reduced in cells infected with fungal conidia. I then observed an increase in surfactant protein-D on PU.1-overexpressed cells. Infection of A. fumigatus conidia was decreased in PU.1-overexpressed cells, whereas the suppression of PU.1 did not lead to any changes in cases of A. fumigatus conidia infection. These results indicate that PU.1 inhibits the infection of A. fumigatus conidia via the expression of surfactant protein-D, suggesting that PU.1 is a key transcription factor for protection against A. fumigatus invasion.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2000년도 추계정기학술대회:지능형기술과 CRM
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• pp.289-299
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• 2000

This study provides an application of datamining approach to CQI(Continuous Quality Improvement) using the discharge summary. First, we found a process variation in hospital infection rate by SPC (Statistical Process Control) technique. Second, importance of factors influencing hospital infection was inferred through the decision tree analysis which is a classification method in data-mining approach. The most important factor was surgery followed by comorbidity and length of operation. Comorbidity was further divided into age and principal diagnosis and the length of operation was further divided into age and chief complaint. 24 rules of hospital infection were generated by the decision tree analysis. Of these, 9 rules with predictive prover greater than 50% were suggested as guidelines for hospital infection control. The optimum range of target group in hospital infection control were Identified through the information gain summary. Association rule, which is another kind of datamining method, was performed to analyze the relationship between principal diagnosis and comorbidity. The confidence score, which measures the decree of association, between urinary tract infection and causal bacillus was the highest, followed by the score between postoperative wound disruption find postoperative wound infection. This study demonstrated how datamining approach could be used to provide information to support prospective surveillance of hospital infection. The datamining technique can also be applied to various areas fur CQI using other hospital databases.

• Journal of the Korean Statistical Society
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• 제35권4호
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• pp.397-407
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• 2006

A new stochastic process is introduced for describing a mechanism of viruses. The process generalizes the $Bartoszy\'{n}ski's$ process ($Bartoszy\'{n}ski$, 1975a, 1975b, 1976) by allowing the stochastic perturbation between consecutive jumps to take into account the persistent infection (the infection without breaking infected cells). It is shown that the new process can be obtained by a weak limit of a sequence of Markov branching processes. Along with the construction of the new process, we study how the stochastic perturbation influences the risk of a symptom in an infected host. For this purpose, the quantal response model and the threshold model are investigated and compared through their induced survival functions.

• The Plant Pathology Journal
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• 제19권1호
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• pp.34-42
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• 2003

The ascomycete Magnaporthe grisea is a pathogen of rice blast and is known to form specialized infection structures called appressoria for successful infection into host cells. To understand the molecular mechanism underlying infection process, appressorium-related genes were identified through global approaches including EST sequencing, differential hybridization, and sup-pression subtractive hybridization. EST database was generated on >2,000 cDNA clones randomly selected from appressorium stage cDNA library. Large number of ESTs showed homology to known proteins possibly involved in infection-related cellular development (attachment, germination, appressorium formation, and colonization) of rice blast fungus. The 1051 ESTs showing significant homology to known genes were assigned to 11 functional categories. Differential hybridization and suppression subtractive hybridization were applied to identify genes showing an appressorium stage specific expression pattern. A number of genes were selected as up-regulated during appressorium formation compared with the vegetative growing stage. Clones from various cDNA libraries constructed in different developmental stages were arrayed on slide glass for further expression profiling study. functional characterization of genes identified from these global approaches may lead to a better understand-ing of the infection process of this devastating plant disease, and the development of novel ways to protect host plant.

• The Plant Pathology Journal
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• 제31권4호
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• pp.421-427
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• 2015

Citrus scab disease is one of the destructive diseases that reduce the value of fruit for the fresh market. We analyzed the process of symptom development after infection with scab pathogen $Elsino{\ddot{e}}$ fawcettii in the susceptible satsuma mandarin leaves to observe the structural modification against pathogen. The cuticle and epidermal cells along with 3-5 layers of mesophyll tissue were degraded 1-2 days post inoculation. Surrounding peripheral cells of degraded tissues grew rapidly and then enveloped the necrotic area along with the growing conidia. Cross sections through the lesion revealed hyphal colonization in epidermis and mesophyll tissues. In response to the pathogen colonization, host cell walls were lignified, inner cells were rapidly compartmentalized and a semi-circular boundary was formed that separated the infected region from the non-infected region, and finally prevented the intercellular pathogen spread.

• International Journal of Computer Science & Network Security
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• 제24권5호
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• pp.205-211
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• 2024

The increasing number of botnet attacks incorporating new evasion techniques making it infeasible to completely secure complex computer network system. The botnet infections are likely to be happen, the timely detection and response to these infections helps to stop attackers before any damage is done. The current practice in traditional IP networks require manual intervention to response to any detected malicious infection. This manual response process is more probable to delay and increase the risk of damage. To automate this manual process, this paper proposes to automatically select relevant countermeasures for detected botnet infection. The propose approach uses the concept of flow trace to detect botnet behavior patterns from current and historical network activity. The approach uses the multiclass machine learning based approach to detect and classify the botnet activity into IRC, HTTP, and P2P botnet. This classification helps to calculate the risk score of the detected botnet infection. The relevant countermeasures selected from available pool based on risk score of detected infection.

• 기본간호학회지
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• 제21권4호
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• pp.392-402
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• 2014

Purpose: This study was done to investigate the status of disinfection and sterilization in healthcare facilities. Method: A survey of 193 Korean healthcare facilities was conducted from February 8 to March 7, 2013. Data were analyzed using descriptive statistics, ${\chi}^2$ test, Fisher's exact test, one-way ANOVA, Scheffe with SPSS WIN 18.0. Results: Of the healthcare facilities 93.2% had specific guidelines for disinfection/sterilization, but only 47.9% had a committee on disinfection/sterilization for decision-making, less than half (42.7%) conducted regular monitoring of actual practices, while 83.9% had established procedures for recovery in case of problems with the disinfection process and 89.0% kept records and archives of disinfection practices. Cleaning process, selection of chemical disinfectants and process of disinfection and sterilization were found to be inadequate in some healthcare facilities. Perception score for adequacy of medical instruments was 8.10, environmental disinfection was 7.20, and sterilizer management was 8.45 out of a possible 10. Conclusion: Compared to larger institutions, smaller healthcare facilities had less effective disinfection and sterilization management systems, while some facilities showed inadequate practices for medical equipment and general sterilization. Better academic and state-level support is recommended for smaller facilities in order to establish a better system-wide management system.

• Journal of Microbiology and Biotechnology
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• 제31권8호
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• pp.1109-1114
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• 2021

Chlamydia pneumoniae is a type of pathogenic gram-negative bacteria that causes various respiratory tract infections including asthma. Chlamydia species infect humans and cause respiratory infection by rupturing the lining of the respiratory which includes the throat, lungs and windpipe. Meanwhile, the function of interleukin-4 (IL-4) in Ch. pneumoniae respiratory infection and its association with the development of airway hyperresponsiveness (AHR) in adulthood and causing allergic airway disease (AAD) are not understood properly. We therefore investigated the role of IL-4 in respiratory infection and allergy caused by early life Chlamydia infection. In this study, Ch. pneumonia strain was propagated and cultured in HEp-2 cells according to standard protocol and infant C57BL/6 mice around 3-4 weeks old were infected to study the role of IL-4 in respiratory infection and allergy caused by early life Chlamydia infection. We observed that IL-4 is linked with Chlamydia respiratory infection and its absence lowers respiratory infection. IL-4R α2 is also responsible for controlling the IL-4 signaling pathway and averts the progression of infection and inflammation. Furthermore, the IL-4 signaling pathway also influences infection-induced AHR and aids in increasing AAD severity. STAT6 also promotes respiratory infection caused by Ch. pneumoniae and further enhanced its downstream process. Our study concluded that IL-4 is a potential target for preventing infection-induced AHR and severe asthma.

• 대한의생명과학회지
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• 제18권3호
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• pp.201-209
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• 2012

Apoptosis is a physiological programmed cell death process. Tubercle bacilli inhibit apoptosis of alveolar macrophages and phagolysosome fusion. We investigated whether the Bcl-2 family anti-apoptotic member, Bfl-1/A1, plays an important role in the anti-apoptotic process during mycobacterial infection. PMA-treated human monocytoid THP-1 cells were infected with mycobacteria (H37Rv, BCG, and K-strain) at a multiplicity of infection (MOI) of 10 for 0, 1.5, 3, 6, 9, 12, 18, 24, 48, or 72 h. In addition, PMA-treated THP-1 cells were pretreated with specific inhibitors for 45 min before stimulation with mycobacteria at an MOI of 10 for 4 h. After the indicated time, the cells were subject to reverse transcription-polymerase chain reaction (RT-PCR) analysis, and a Bfl-1/A1-specific Western blot was performed. In PMA-differentiated THP-1 cells, the expression level of Bfl-1/A1 mRNA was increased by Mycobacterium tuberculosis (MTB) H37Rv infection. The mRNA level of Bfl-1/A1 peaked 3 h after MTB infection, then declined gradually until 9 h. However, Bfl-1/A1 mRNA induction gradually re-increased from 24 h to 72 h after MTB infection. No difference in Bfl-1/A1 expression was detected following infection with MTB H37Rv, K-strain, or M. bovis BCG. These results were not dependent on mycobacterial virulence. Moreover, mRNA levels of other anti-apoptotic molecules (Mcl-1, Bcl-2, and Bcl-xL) were not increased after MTB H37Rv or K-strain infection. These results suggest that mycobacteria induce the innate immune host defense mechanisms that utilize Bfl-1/A1 molecules at early time points, regardless of virulence.

• 한국임상수의학회지
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• 제21권3호
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• pp.243-247
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• 2004

This studies was carried out to investigate a process of formation for the granulomatous lesions in the liver and the haematological variation with the lapse of time after infection of Capillaria hepatica in dogs. Twelve crossbred puppies, about 3 months of age and 2-3 kg of body weight, were administered with 2,000 Capillaria hepatica infective eggs. Every four puppies was sacrificed on 1 week, 3 weeks and 5 weeks after infection, respectively. Although no marked clinical sign was noticed, total leukocyte values were increased peak on 1 week, and then reduced gradually on 3 weeks and 5 weeks after infection. Absolute differential counts of neutrophils and lymphocytes were significantly increased on 1, 3 and 5 weeks after infection. Absolute differential counts of monocytes and eosinophils were trend to increase during the experimental periods. On grossly findings, liver congestions were observed in all infected puppies, and a few white specks were scattered under liver capsule in one puppy on 3 weeks and two puppies on 5 weeks after infection. On microscopic findings, many fresh larvae were observed in the liver tissues in one puppy on 1 week after infection. A worm was decayed and only a portion of cuticle was shown in one puppy on 3 weeks after infection. Around the central necrotic material, the layers of thick macrophages with a few giant cells and lymphocytes with fibrous connective tissues were consisted the granulomatous lesions on 5 weeks after infection.