• Clinical and Experimental Pediatrics
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• v.52 no.3
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• pp.330-338
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• 2009

Purpose : The causes of acute lower respiratory tract infection (ALRTI) are mostly attributable to viral infection, including respiratory syncytial virus (RSV), parainfluenza virus (PIV), influenza virus A/B (IFV A/B), or adenovirus (ADV). Several Korean studies reported human metapneumovirus (hMPV) as a common pathogen of ALRTI. However, studies on seasonal distribution and clinical differences relative to other viruses are insufficient, prompting us to perform this study. Methods : From November 2006 to October 2007, we tested nasopharyngeal aspiration specimens in children hospitalized with ALRTI with the multiplex reverse transcriptase-polymerase chain reaction to identify 6 kinds of common pathogen (hMPV, RSV, PIV, IFV A/B, and ADV). We analyzed positive rates and clinical features by respiratory chart review. Results : We detected 38 (8.4%) hMPV-positive cases out of 193 (41.8%) virus-positive specimens among 462 patients. HMPV infection prevailed from March to June with incidence peaking in April. HMPV-positive patients were aged 15 years (76.3%), and the ratio of boys to girls was 1.2:1. The median age was 27 months. HMPV primarily caused pneumonia (76.3 %) (P=0.018). Average hospitalization of HMPV-associated ALRTI patients was 5.8 days. In addition, they showed parahilar peribronchial infiltration (100%) on chest X-ray, normal white blood cell count (73.7%), and negative C-reactive protein (86.8 %) (P>0.05). All hMPV-positive patients recovered without complication. Conclusion : HMPV is a common pathogen of ALRTI in Korean children, especially in 1-5 year olds, from March to May. Immunocompetent children diagnosed with hMPV-associated ALRTI may have a good prognosis.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.184-189
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• 2011

'Younghan' (Hordeum vulgare L.), a winter barley for forage use, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute of Crop Science, Rural Development Administration in 2008. It was derived from a cross between $F_1$['YB3433-3B-5'/'YB3135-3B-2-3'] and 'YB3135-3B-2-3'. 'SB971305-B-B-B-4-4' line was selected for its earliness, resistance to disease and good agronomic characteristics. The promising line showed both high yield and lodging resistance in the yield trials in Iksan in 2004 to 2005, and designated as 'Iksan420'. The line was subsequently evaluated for winter hardiness, earliness, and yield at eight locations throughout Korea for two years from 2007 to 2008 and finally named as 'Younghan'. It has the growth habit of IV, erect plant type, green leaf and thick culm in diameter. Its heading date was April 24, and the maturing date was May 25 in paddy field conditions, which were one day earlier than those of the check cultivar 'Youngyang'. The cultivar 'Younghan' had better winter hardiness, and resistance to lodging and BaYMV than those of the check cultivar did. The average forage dry matter yield of 'Younghan' was approximately 12.0 MT/ha in adapted region. 'Younghan' also showed 8.5% of crude protein content, 27.2% of ADF, and 67.1% of TDN, including higher grade of silage quality for whole crop barley. This cultivar would be suitable for (area with daily minimum temperature in January) above $-8^{\circ}C$ in Korean peninsula.

• Clinical and Experimental Pediatrics
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• v.49 no.4
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• pp.401-409
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• 2006

Purpose : Human metapneumovirus(hMPV) is a respiratory viral pathogen that causes a wide spectrum of illnesses, ranging from asymptomatic infection to severe bronchiolitis. The virus has been identified world widely, but so far it has not been published in Korea. Methods : We obtained clinical samples by nasopharyngeal aspiration from 218 children hospitalized due to acute lower respiratory tract infections at Soonchunhyang University Hospital in Cheonan from October, 2004 to April, 2005. We designed specific primers from conserved region of fusion glycoprotein of hMPV. Total RNA was extracted and RT-PCR was performed, and single specific 423 bp product was obtained. The PCR product was confirmed to be fusion glycoprotein RNA by sequencing. Results : We detected hMPV in 15(6.9 percent) of the 218 hospitalized children. The infected children comprised nine boys and six girls; their mean age was 2.8 years(5 mo-12 yrs) and they were diagnosed with pneumonia(60 percent), bronchiolitis(33.3 percent), croup(6.6 percent). The number of cases of detected hMPV in Korea increased dramatically during the period from March to May 2005. Conclusion : hMPV is circulating in Korean children and is associated with respiratory tract infection. Additional studies are required to define the epidemiology and the extent of diseases in the general population caused by hMPV.

• Korean Journal of Microbiology
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• v.45 no.3
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• pp.251-256
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• 2009

Leaf samples and bulbs showing characteristic symptoms of virus infection were collected from Gang-won, Chung-nam, and Jeju Province of Korea in 2008-2009. Three viruses, Lily symptomless virus (LSV), Lily mottle virus (LMoV), and Cucumber mosaic virus (CMV) were detected by RT-PCR. Virus-infected plant samples were identified; 12 plants with LSV, 20 plants with LMoV, and 1 plant with CMV. Of the twelve LSV infected samples, seven samples were found to be mix-infected with LMoV and LSV. Symptoms of LMoV and LSV mixed infection were fairly severe, like as vein clearing, leaf curling, leaf mottling, leaf mosaic, and yellow streaking. Mixed infection with LMoV and LSV was also found in lily bulbs which have been stored under unfavorable environmental conditions. LMoV predominated in our tests, whereas spread of Lilyvirus X (LVX) was not found. The nucleotide sequences of coat protein (CP) region of seven isolates (4 LMoV, 2 LSV, and 1 CMV) were compared with the corresponding regions of LMoV (AJ564636), LSV (AJ516059) and CMV(AJ296154). The nucleotide sequence homologies between reference viruses and seven isolates were 95-99%. Complete sequencing of seven isolates is necessary to obtain more information on the molecular characteristics of these viruses as well as to increase sensitivity and rapidity of viral detection.

• Clinical and Experimental Pediatrics
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• v.51 no.7
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• pp.729-735
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• 2008

Purpose : Chlamydia trachomatis is one of the most common sexually transmitted diseases and is also a cause of pneumonia in infants. Respiratory infections by respiratory viruses are also common for infants. The objectives of this study were to identify the clinical manifestations and to determine the prevalence of C. trachomatis respiratory infections and coinfections by respiratory viruses in infants younger than 6 months of age. Methods : For this study, we enrolled 6 months or younger infants who were admitted to the Dankook University Hospital between January 2002 and July 2007, with respiratory symptoms. Nasopharyngeal aspirates or throat swabs were collected within s d of hospitalization and C. trachomatis was detected using polymerase chain reaction (PCR). Patients who tested positive underwent multiplex PCR for respiratory viruses. Results : A total of 690 patients underwent chlamydial PCR testing and 36 (5.2%) had positive results. Of the 36, 28 (78%) were male; 30 were vaginally delivered. From the 36 patients positive for C. trachomatis, 26 underwent multiplex respiratory viral PCR; 12 were coinfected with viruses. Respiratory syncytial virus (RSV) was the most frequent pathogen that was detected in 6 patients. Increased C-reactive protein and fever were significant in patients coinfected with respiratory viruses. Conclusion : C. trachomatis can infected in infants delivered by cesarean section as well as in 6 months old or younger infants. Infant with C. trachomatis respiratory infections can also be coinfected with respiratory infection also coinfected with respiratory viruses. Further studies are needed to better understand the prevalence rates of the this infection and its coinfection rate with respiratory viruses.