• Biomedical Science Letters
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• v.21 no.4
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• pp.165-171
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• 2015

Microbial pathogens are responsible for most of the rapidly-spreading deadly infectious diseases against humans. Thus, there is an urgent need for efficient and rapid detection methods for infectious microorganisms. The detection methods should not only be targeted and specific, but they have to be encompassing of potential changes of the pathogen as it evolves and mutates quickly during an epidemic or pandemic. The existing diagnostics such as the antibody-based ELISA immunoassay and PCR methods are too selective and narrowly focused; they are insufficient to capture newly evolved mutant strains of the pathogen. Here, we introduce a fresh perspective on some new technologies, including aptamers and next generation sequencing for pathogen detection. These technologies are not in their infancy; they are reasonably mature and ready, and they hold great promise for unparalleled applications in pathogen detection.

• Journal of Korean Medical classics
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• v.30 no.2
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• pp.11-29
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• 2017

Objectives : Contemporary researches suspect that, contrary to the past belief, the understanding that the cause of warm pathogen lies in the upper portion of human body is an understanding that had been well-established even before Yetianshi. This new understanding now requires us to contemplate the process of theoretical development which this understanding, termed Onsasangsu, had taken within the boundary of the theory of warm pathogen. This paper aims to shed light on this within the framework that this is the emergence of a new theory of warm pathogen caused by a new understanding of warm pathogen. Methods : First, the theories of warm pathogen as developed by historical doctors were studied, and elements that seem to be related to the understanding of Onsasangsu were selected and studied to understand their theoretical characteristics. Furthermore, the paper studied what academic significance do these theories have on the development of the theory of warm pathogen. Results & Conclusions : Provided that the underlying assumption of Onsasangsu is that febrile diseases are caused through moutn and nose, the study showed that this understanding arose before the period of Qing Dynsasty from the need by many doctors to differentiate the pathogens of various diseases such as the disease of heat, febrile disease, and epidemic. The reason that these discussions could not have much impact on the study of febrile disease during the Qing Dynasty could be because they were not passed on down to the future generations, or because commonly held perspective was unable to accept criticisms.

• ALGAE
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• v.32 no.1
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• pp.29-39
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• 2017

Geographic distributions of pathogens are affected by dynamic processes involving host susceptibility, availability and abundance. An oomycete, Pythium porphyrae, is the causative agent of red rot disease, which plagues Pyropia farms in Korea and Japan almost every year and causes serious economic damage. We isolated an oomycete pathogen infecting Pyropia plicata from a natural population in Wellington, New Zealand. The pathogen was identified as Pythium porphyrae using cytochrome oxidase subunit 1 and internal transcribed spacer of the rDNA cistron molecular markers. Susceptibility test showed that this Pythium from New Zealand was able to infect several different species and genera of Bangiales including Pyropia but is not able to infect their sporophytic (conchocelis) phases. The sequences of the isolated New Zealand strain were also identical to Pythium chondricola from Korea and the type strain from the Netherlands. Genetic species delimitation analyses found no support for separating P. porphyrae from P. chondricola, nor do we find morphological characters to distinguish them. We propose that Pythium chondricola be placed in synonymy with P. porphyrae. It appears that the pathogen of Pyropia, both in aquaculture in the northern hemisphere and in natural populations in the southern hemisphere is one species.

• Journal of Microbiology and Biotechnology
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• v.33 no.2
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• pp.235-241
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• 2023

Hyaluronidase (HAase) can enhance drug diffusion and dissipate edema by degrading hyaluronic acid (HA) in the extracellular matrix into unsaturated HA oligosaccharides in mammalian tissues. Microorganisms are recognized as valuable sources of HAase. In this study, a new hyaluronate lyase (HAaseD) from Bacillus sp. CQMU-D was expressed in Escherichia coli BL21, purified, and characterized. The results showed that HAaseD belonged to the polysaccharide lyase (PL) 8 family and had a molecular weight of 123 kDa. HAaseD could degrade chondroitin sulfate (CS) -A, CS-B, CS-C, and HA, with the highest activity toward HA. The optimum temperature and pH value of HAaseD were 40℃ and 7.0, respectively. In addition, HAaseD retained stability in an alkaline environment and displayed higher activity with appropriate concentrations of metal ions. Moreover, HAaseD was an endolytic hyaluronate lyase that could degrade HA to produce unsaturated HA oligosaccharides. Together, our findings indicate that HAaseD from Bacillus sp. CQMU-D is a new hyaluronate lyase and with excellent potential for application in industrial production.

• Journal of Ginseng Research
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• v.43 no.1
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• pp.1-9
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• 2019

Background: Korean ginseng is an important cash crop in Asian countries. However, plant yield is reduced by pathogens. Among the Ilyonectria radicicola-species complex, I. mors-panacis is responsible for root-rot and replant failure of ginseng in Asia. The development of new methods to reveal the existence of the pathogen before cultivation is started is essential. Therefore, a quantitative real-time polymerase chain reaction method was developed to detect and quantify the pathogen in ginseng soils. Methods: In this study, a species-specific histone H3 primer set was developed for the quantification of I. mors-panacis. The primer set was used on DNA from other microbes to evaluate its sensitivity and selectivity for I. mors-panacis DNA. Sterilized soil samples artificially infected with the pathogen at different concentrations were used to evaluate the ability of the primer set to detect the pathogen population in the soil DNA. Finally, the pathogen was quantified in many natural soil samples. Results: The designed primer set was found to be sensitive and selective for I. mors-panacis DNA. In artificially infected sterilized soil samples, using quantitative real-time polymerase chain reaction the estimated amount of template was positively correlated with the pathogen concentration in soil samples ($R^2=0.95$), disease severity index ($R^2=0.99$), and colony-forming units ($R^2=0.87$). In natural soils, the pathogen was recorded in most fields producing bad yields at a range of $5.82{\pm}2.35pg/g$ to $892.34{\pm}103.70pg/g$ of soil. Conclusion: According to these results, the proposed primer set is applicable for estimating soil quality before ginseng cultivation. This will contribute to disease management and crop protection in the future.

• IMMUNE NETWORK
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• v.21 no.6
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• pp.40.1-40.20
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• 2021

Mycobacteroides abscessus (previously Mycobacterium abscessus; Mabc), one of rapidly growing nontuberculous mycobacteria (NTM), is an important pathogen of NTM pulmonary diseases (NTM-PDs) in both immunocompetent and immunocompromised individuals. Mabc infection is chronic and often challenging to treat due to drug resistance, motivating the development of new therapeutics. Despite this, there is a lack of understanding of the relationship between Mabc and the immune system. This review highlights recent progress in the molecular architecture of Mabc and host interactions. We discuss several microbial components that take advantage of host immune defenses, host defense pathways that can overcome Mabc pathogenesis, and how host-pathogen interactions determine the outcomes of Mabc infection. Understanding the molecular mechanisms underlying host-pathogen interactions during Mabc infection will enable the identification of biomarkers and/or drugs to control immune pathogenesis and protect against NTM infection.

• Journal of Korean Medical classics
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• v.32 no.4
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• pp.17-33
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• 2019

Objectives : The verse, "冬不藏精, 春必病溫", which had much influence, has been falsely referenced as contents of "Neijing". This study aims to examine this process, while looking at its theoretical meaning within clinical practice. Methods : The origins of the concept "冬不藏精, 春必病溫" are explained through annotations of "Neijing" and Li Dong Yuan(李東垣)'s interpretation of Shanghan(傷寒), while its clinical meaning is examined through theories of doctors's who applied the concept in their practices. Results : The beginning of "冬不藏精, 春必病溫" could be traced back to Li's annotation of the verse "冬傷于寒, 春必病溫" from the "Neijing", where he based his understanding on the concept "少陰不藏." Since then, the discourse on "冬傷于寒, 春必病溫" has been replaced by "冬不藏精, 春必病溫" as a new concept to explain the pathology of Wenbing(溫病). These discussions followed the line of thought that by failure to store Jing(精) during the winter, Cold pathogen would infiltrate, hiding itself in Shaoyin(少陰). Various arguments on how the Cold pathogen would develop into Wenbing and its treatment followed. Conclusions : "冬不藏精, 春必病溫" can be understood as the result of a new interpretation of "冬傷于寒, 春必病溫" through the perspective of Cold pathogen infiltration based on "少陰不藏".

• Parasites, Hosts and Diseases
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• v.57 no.2
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• pp.101-115
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• 2019

The pathogenesis of cerebral malaria is biologically complex and involves multi-factorial mechanisms such as microvascular congestion, immunopathology by the pro-inflammatory cytokine and endothelial dysfunction. Recent data have suggested that a pleiotropic T-cell immunomodulatory protein (TIP) could effectively mediate inflammatory cytokines of mammalian immune response against acute graft-versus-host disease in animal models. In this study, we identified a conserved homologue of TIP in Plasmodium berghei (PbTIP) as a membrane protein in Plasmodium asexual stage. Compared with PBS control group, the pathology of experimental cerebral malaria (ECM) in rPbTIP intravenous injection (i.v.) group was alleviated by the downregulation of pro-inflammatory responses, and rPbTIP i.v. group elicited an expansion of regulatory T-cell response. Therefore, rPbTIP i.v. group displayed less severe brain pathology and feverish mice in rPbTIP i.v. group died from ECM. This study suggested that PbTIP may be a novel promising target to alleviate the severity of ECM.

• Fibers and Polymers
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• v.4 no.2
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• pp.54-58
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• 2003

Previous research on healthcare workers’ protection has concentrated on liquid barrier protection by providing impermeable personal articles such as latex gloves. This property is of high importance but since most blood-borne pathogen transmissions in the healthcare industry are caused by needle-stick injuries, protection from sharp invasive instruments should also be of high concern. And since latex and alike provide no protection against needle-stick injuries, new protective systems need to be developed and evaluated. This part of the study provides a review regarding the current practice of protection and the serious problems that arise from needle-flick injuries. Additionally, the development of new protective system is described. In part II of the study, evaluation of the new system will be provided.

• ALGAE
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• v.32 no.2
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• pp.155-160
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• 2017

Red rot disease has caused a major decline in Pyropia (Nori) crop production in Korea, Japan, and China. To date, only Pythium porphyrae (Pythiales, Oomycetes) has been reported as the pathogen causing red rot disease in Pyropia yezoensis (Rhodophyta, Bangiales). Recently, Pythium chondricola was isolated from the infected blades of Py. yezoensis during molecular analyses using the mitochondrial cox1 region. In this study, we evaluated the pathogenicity of P. chondricola as an algal pathogen of Py. yezoensis. Moreover, a new cox2 marker was developed with high specificity for Pythium species. Subsequent to re-inoculation, P. chondricola successfully infected Py. yezoensis blades, with the infected regions containing symptoms of red rot disease. A novel cox2 marker successfully isolated the cox2 region of Pythium species from the infected blades of Py. yezoensis collected from Pyropia aquaculture farms. cox2 sequences showed 100% identity with that of P. chondricola (KJ595354) and 98% similarity with that of P. porphyrae (KJ595377). The results of the pathogenicity test and molecular analysis confirm that P. chondricola is a new algal pathogen causing red rot disease in Pyropia species. Moreover, it could also suggest the presence of cryptic biodiversity among Korean Pythium species.