• Parasites, Hosts and Diseases
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• v.43 no.3 s.135
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• pp.111-114
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• 2005

The present study investigated the prevalence rate of Cryptosporidium parvum as a cause of diarrhea. We examined 942 stools of unidentified reasons occurring in patients in whom no immunosuppression had been detected. We examined the stools for Cryptosporidium parvum via modified acid-fast staining. The clinical records of all of the positive patients were then analyzed. Nine ($1\%$) of the stools among the 942 diarrheal patients were positive for C. parvum. The positive rate in the males was $1.1\%$ (6/522) and the positive rate of the females was $0.7\%$ (3/420). Age distribution revealed that the highest positive rates were in patients in their sixties, with a positive rate of $2.5\%$ (4/158). In the clinical tests, levels of c-reactive protein, erythrocyte sedimentation rates, and neutrophil proportions were normally increased in the peripheral blood, whereas the lymphocyte proportion exhibited a tendency towards decrease. The pathological findings were compatible with an inflammatory reaction in the host.

• The Plant Pathology Journal
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• v.22 no.2
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• pp.131-138
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• 2006

Two strains of Cucumber mosaic virus (CMV) isolated in Kuwait were confirmed their infectivity based on symptomatology and host range on different cultivars of tomato (Lycopersicon esculentum), tobacco(Nicotiana tabacum L.) and squash (Cucurbita pepo). The pattern of symptoms differed for the two CMV strains in tomato and tobacco, showing severe stunting and mosaic symptoms with one strain designated KU2, and almost symptomless with the other strain designated KU1. A satellite RNA 5 (sat-RNA) was found to be associated with the KU1 strain and was characterized as a benign viral satellite RNA. Using reverse transcription and polymerase chain reaction (RT-PCR) with sat-RNA specific primers, an amplified PCR product of about 160bp was determined and analyzed by gel electrophoresis. This naturally occurring benign viral satellite RNA was successfully used as a biological control agent to protect tomato plants against the severe KU2 strain. Tomato plants grown in plant-growth chambers, were preinoculated with KU1 containing the benign viral satellite and then challenge inoculated with the severe KU2 strain at different time intervals. All plants challenged three weeks after preinoculation showed nearly complete protection from subsequent infection by the severe strain. This biological control technology using plant viruses was found protective and could be successfully established sooner after the preinoculation.

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2003.10a
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• pp.29-29
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• 2003

Mycoplasma hyopneumoniae is among the most prevalent and important infectious agents associated with porcine respiratory disease complex. The airway dagame caused by M. hyopneumoniae adversely affect the pulmonary host defense mechanisms and may lead to secondary bacterial infections. Culture is considered to be the "gold standard" for diagnosis but this is a very slow and labor-intensive procedure. Isolation of M. hyopneumoniae is complicated by its fastidious nature and extremely slow growth. Thirty days of incubation may be necessary to detect the organism in primary broth cultures. The purposes of the study were (ⅰ) to develop nested PCR for the detection of M. hyopneumoniae for the detection of M. hyopneumoniae DNA in the formalin-fixed, paraffin-embedded lung tissues from experimentally and naturally infected pigs and (ⅱ) to compare the utility of nested PCR with in situ hybridization. (omitted)

• Korean Journal of Veterinary Research
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• v.38 no.3
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• pp.574-580
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• 1998

Anthrax caused by Bacillus anthracis is one of the most important zoonotic diseases in the worldwide. To control and prevent the disease effectively, several methods such as development of a fast and specific diagnostic method and vaccine, education etc, have been carried out. However, it still has a problem in the control and prevention. To control, the most important method is the prevention of direct or indirect contact of the causative agent with susceptible host. Therefore, we developed a fast and specific detection method, polymerase chain reaction, of B anthracis from soil and infected animals because the organism could survive long time in the environment including soil due to formation of spore. With the method, virulence genes of B anthracis were successfully amplified from experimentally infected soil and mice. Up to $4.2{\times}10$ of the organisms per gram could be detected with the PCR method from experimentally infected soil. These results suggested that this PCR method could be effectively used not only to detect B anthracis in soil and infected animal but also to provide the information to prevent the disease.

• Journal of fish pathology
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• v.18 no.2
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• pp.119-124
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• 2005

Two species of myxosporean parasites - Parvicapsula anisocaudata and an unidentified myxosporean were found in the lumina of renal tubules and the tubular epithelium, respectively, from cultured olive flounder, Paralichthys olivaceus in Korea. The latter was also seen in interstitial tissue of spleen and interrenal gland of the head kidney. Group of pseudoplasmodia of P. anisocaudata were firmly attached on the epithelium of renal tubules through pseudopodia. In the renal tubule epithelium, a group of unidentified myxosporean trophozoites, which were 2-3 times larger than intraluminal trophozoites of P. anisocaudata, was observed. The parasites being burst out into the lumen was occasionally encountered with partial break of the epithelium. Although infection of P. anisocaudata and unidentified myxosporean parasites did not induce any cellular reaction of the host, occlusion of renal tubules and rupture of renal epithelium would impact negatively on the renal functions of severely infected fish.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.4
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• pp.462-466
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• 2001

To understand molecular mechanisms of mouse mammary gland involution, clones were isolated by differential screening of a cDNA library. Partial sequences of a clone showed 100% identity to cDNA sequences of mouse lysozyme P gene. Northern analysis was performed to examine expression levels of lysozyme mRNA in mammary gland at several physiological states. Expression of lysozyme gene was induced at involution day 5 compared with lactating stage. High levels of lysozyme mRNA were also detected at virgin tissues. Two types of separate genes, P and M lysozyme, have been known in mouse, and we found that both lysozyme P and M genes were expressed in mammary tissues by reverse transcriptase-polymerase chain reaction. The lysozyme enzyme activity determined by lysoplate assay was also higher in involuted mammary tissues compared with lactating tissues, showing a similar trend to its mRNA levels. Lysozyme is an antimicrobial protein and involved in host defense mechanism. The increase in lysozyme gene expression may help to prevent microbial infection during mammary gland involution at which stage the residual milk in the mammary gland provides good nutritional sources for microbial growth.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.2
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• pp.154-159
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• 2006

Interleukin-18 (IL-18), otherwise known as interferon-gamma-inducing factor (IGIF), is one of several well characterized and important cytokines that contribute to host defenses. The complementary DNA (cDNA) of mature human interleukin-18 gene (hIL-18) was fused with the signal peptide of the rice amylase 1A gene (Ramy1A) and introduced into the plant expression vector under the control of a duplicated CaMV 35S promoter. The recombinant plasmid was transformed into tobacco (Nicotiana tabacum L. cv Havana) using the Agrobacterium-mediated transformation method. The integration of the hlL-18 gene into the genome of transgenic tobacco plants was confirmed by polymerase chain reaction (PCR) amplification and its expression was observed in the suspension cells that were derived from the transgenic plant callus by using Northern blot analysis. The hlL-18 protein was detected in the extracts of the transgenic callus and in the medium of the transgenic tobacco suspension culture by using immunoblot analysis. Based upon enzyme-linked immunosorbant assay (ELISA) results, the expression level of the hlL-18 protein approximated $166{\mu}g/L$ in the suspension culture medium. Bioassay results from the induction of $interferon-{\gamma}$ from a KG-1 cell line indicated that the hlL-18 secreted into the suspension culture medium was bioactive.

• The Plant Pathology Journal
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• v.28 no.2
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• pp.191-196
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• 2012

Periwinkle seedlings (Cantharanthus roseus) were inoculated with jujube witches'- broom (JWB) phytoplasma via grafting to analyze the migration of JWB phytoplasmas within the host plant. The phytoplasmas were detected using nested polymerase chain reaction (PCR) and fluorescence microscopy. Fluorescence microscopy was a simple and easy method of detecting phytoplasmas; however, it was not sufficiently sensitive to detect very low phytoplasma concentrations. Therefore, the migration of JWB phytoplasma was investigated through PCR. The first migration of JWB phytoplasma from an infected tissue to healthy tissues occurred late. After grafting, the phytoplasmas moved from the inoculated twig (or scion) to the main stem, which took 28 days. Afterward, the phytoplasma migrated faster and took less than 4 days to spread into the roots from the main stem. All twigs were then successively colonized by the JWB phytoplasmas from the bottom to the top. JWB phytoplasma was detected via nested PCR in all parts of the periwinkle seedling 82 days after inoculation. Based on these results, the inoculated JWB phytoplasma appeared to migrate downward to the roots along the main stem during the early stages, and then continued to move upward, colonizing twigs along the way until they reached the apex.

• Parasites, Hosts and Diseases
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• v.39 no.1
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• pp.43-48
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• 2001

We have studied the genetic differences among four isolates of Trichinella including a new strain of Trichinella spiralis (ISS 623) recently found from a human case who took a badger in Korea. Because they have a different host origin and came from geographically separated regions, we supposed the genetic pattern of the isolates might be different as had been previously reported. It was analysed by PCR-RFLP analysis of the rDNA repeat that can readily distinguish a species or strain from others. Isolated genomic DNA of each isolate of Trichinella larvae was amplified with ITSl specific primers and digested with restriction endonucleases. The PCR product of ITSl was confirmed using Southern blot analysis to be a 910 Up fragment. The restriction fragments of each isolate had variable patterns when it was digested with Rsa I only. According to the RFLP patterns, the estimated genetic divergence between each isolate was different. In conclusion, four isolates of Thichinella including a new strain of T. spiralis obtained from a Korean patient may have genetic differences in the ITSl region and the Shanghai isolate was genetically more similar to the Japanese unknown isolate than others in the ITSl region.

• Korean Journal of Microbiology
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• v.38 no.1
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• pp.19-25
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• 2002

Colletotrichum species are important fungal pathogen that cause great damages on various host plant species worldwide. In Korea, Colletotrichum species cause massive economic losses on apple, peach, grape, and essecially, sweet persimon productions. In the past, Identification of the pathogen and the studies on the genetic relationships among the pathogenic isolates were mainly based on morphology, cultural characteristics, and the difference in pathogenicity. However, in recent years, these traditional methods have been replaced with molecular methods to solve the difficulty of classification on pathogens. Therefore, in this study, RAPD and PCR-RFLP methods were employed for the studies of genetic relationship among the different isolates of Colletotrichum species that cause damages on sweet persimon. As a results of genetic relationship analysis, Colletotrichum species tested were divided into two big groups or five small groups.