• Clinical and Experimental Pediatrics
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• v.48 no.5
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• pp.500-505
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• 2005

Purpose : This study was designed to estimate the prevalence of Mycoplasma pneumoniae infection during an epidemic period by means of examining the antibody conversion rate and to investigate the association of the antibody conversion with age, initial antibody titer, and atopy. Methods : We chose 191 children whose antibody titer to M. pneumoniae was negative, 1 : 40, or 1 : 80 during the first half of 2003. After the second half of 2003 when the M. pneumoniae epidemic occurred, follow-up collection of sera was performed during the first half of 2004. M. pneumoniae antibody titer was measured by Serodia-Myco II particle agglutination test. Results : Of 191 children, antibody conversion was detected in 83 children(43.5 percent). No significant difference was found between the conversion and non-conversion group with respect to age, sex and atopy. Dividing the subjects into four groups by age, results on the antibody conversion rate revealed no significant differences between the groups. Assessed by initial antibody titer, a diminished trend of conversion rate was observed in children with 1 : 80 titer but the difference was not significant. There was no significant difference in the antibody conversion rate between atopic and non-atopic children. Conclusion : Based on the antibody conversion rate in this study, the prevalence of M. pneumoniae infection during an epidemic period was estimated to be 43.5 percent. This high infection rate suggests that during an epidemic, we should bear in mind M. pneumoniae as an important etiologic agent for respiratory infection in children.

• Tuberculosis and Respiratory Diseases
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• v.42 no.2
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• pp.175-183
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• 1995

Background: The incidence of mycoplasmal pneumonia is predominantly at childhood and early adulthood, but in adults, its incidence is low and its symptoms and physical findings are nonspecific. The definite diagnosis of M. pneumoniae pneumonia can be made by sputum culture, but requires several weeks for positive results, and the early diagnosis must initially be based on the serologic tests and appropriate clinical findings. Thus, we evaluated the clinical aspects of M. pneumoniae pneumonia in the adults patients. Method: Among the admitted patients due to pneumonia, the definite diagnosis is anti-M. pneumoniae antibody titer of $\geq$ 1:40 and a single cold agglutinin titer of $\geq$ 1:64. The presumptive diagnosis is anti-M. pneumoniae antibody titer of $\geq$ 1:40 or a single cold agglutinin titer of $\geq$ 1:64 and the clinical characteristics or chest X-ray findings are compatible with M. pneumoniae pneumonia. We studied the age and sex distribution, seasonal distribution, clinical symptoms, physical findings, serologic test, chest X-ray findings, treatment and its progression. Results: 1) The age distribution was even and the ratio of male to female was 1:1. 2) The monthly distribution was most common in January(16.7%) and the seasonal distribution in autumn and winter(autumn: 30%, winter: 33.3%). 3) The cold agglutinin titers were higher than 1:64 in 12 cases(40%), and reached the peak level around 2 weeks from onset and antimycoplasma antibody titers were higher than 1:160 in 5 cases(16.7%). 4) On the chest X-ray, pulmonary infiltration was noted in 28 cases(93.3%) among 30 cases and right lower lobe involvement was the most common(33.3%) and both lower lobe involvement was noted in 7 cases(23.3%). 5) The mean treatment duration was most common(33.3%) in 1 week to 2 weeks after admission and 26 cases(86.7%) were improved within 4 weeks. 6) On admission, there was fever(${\geq}38.9^{\circ}C$) in 17 cases(56.7%), and the fever subsided in 12 cases(70%) within 3 days after treatment using erythromycin. Conclusion: The mycoplasmal pneumonia in adults shows milder clinical patterns than that in childhood and can be completely recovered without complication by early diagnosis and treatment.

• Korean Journal of Poultry Science
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• v.37 no.2
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• pp.181-190
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• 2010

Mycoplasma gallisepticum (MG) infection results in severe economic loss in the poultry industry. In the previous reports, F strain, one of the MG live vaccine strains, could protect the bird from field infection of MG strains. In this study, efficacy of PoulShot$^{(R)}$ MG-F vaccine againset mycoplasma gallisepticum infection was evaluated for filed application in commercial layers. Commercial layers from two different farms received with PoulShot$^{(R)}$ MG-F, MG-F live vaccine at 9~14 weeks of age. Serological immune response to MG vaccine, the persistency of MG vaccine strain in the upper respiratory tracts and egg production rate were evaluated in the vaccinated, contacted or nonvaccinated flocks. The serological response was first detected at 3 weeks after vaccination (WAV) and persisted for 31 WAV. The MG vaccine strains were also persisted for 31 WAV based on the reisolation and PCR detection. There was no difference between the vaccinated or non-vaccinated flocks in the egg production rate but in the abnormality rate of eggs. Based on the above results, we suggested that the PoulShot$^{(R)}$, MG-F live vaccine was fully immunogenic and had characteristics of long persistence in the upper respiratory trachea which will reduce economic loss caused by MG infection in the layer farms.

• Journal of Korean Society of Forest Science
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• v.66 no.1
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• pp.79-81
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• 1984

Protein profiles of healthy and witches' broom (mycoplasma) infected jujube plants (Zizyphus jujuba) were investigated by 2-30% linear gradient polyacrylamide gel electrophoresis. Distinct differences in band patterns between healthy and infected samples were observed. Gels from samples of healthy leaves showed a characteristic protein band in the 50kd-range, which was not detected in infected leaves. Band with 25kd was more distinct in the infected leaves, whereas band with 198kd was more apparent in the healthy leaves. Healthy-looking leaves in the infected samples demonstrated the characteristic band of 50kd with less intensity showing intermediate pattern between healthy leaves and infected leaves. In contrast with leaf samples, gels from infected stem samples showed a characteristic band in the 335kd-range which was absent in healthy stem samples.

• Pediatric Infection and Vaccine
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• v.12 no.2
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• pp.135-139
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• 2005

Purpose : We investigated the clinical manifestations, radiographic and laboratory findings of children with M. pneumoniae pneumonia(MP) according to their age. Methods : A total of 75 children with MP who admitted to The Catholic University, Daejeon St. Mary's Hospital from July 2003 to February 2004, were classified into the three age groups : the ${\leq}2$ years of age(16 children), the children between 3 and 5 years of age(35 children), and the ${\geq}6$ years and older(24 patients). The diagnosis of MP was depended on the titers of anti-mycoplasma antibody that were measured 2 times, at admission and at discharge. Results : The total duration of the fever and the length of hospitalization were not different among the age groups. Although the white blood cell(WBC) value and differential was significantly different between the groups(P<0.01), a similar number in the WBC and reduced lymphocyte proportion was observed in all age groups compared to age-matched references. The patterns of pneumonia were significantly different according to age, i.e. segmental or lobar patterns were observed in 5 cases(31.3%) in the ${\leq}2$ years old group, but 16 cases(66.6%) in the >6 years old group(P<0.01). Conclusion : Although there was no difference in clinical findings according to age in MP, the radiographic finding was more severe in older children.

• Pediatric Infection and Vaccine
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• v.20 no.2
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• pp.71-80
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• 2013

Objectives: Outbreaks of pneumonia caused by Mycoplasma pneumoniae (MP) occur every 3-4 years in Korea, most recently in 2011. The aim of our study was to determine the optimal time to perform indirect particle agglutination antibody assays to improve early diagnosis of MP pneumonia in children. Methods: A database of 206 pediatric patients treated for pneumonia at the Hanyang University Hospital from June to October 2011 was analyzed retrospectively for demographic characteristics and laboratory test results. Results: Among the 206 patients treated for pneumonia during the study period, there were 160 children (mean age, 5.44 years) diagnosed with MP pneumonia, who were studied further. The mean age of these MP pneumonia patients was 5.44 years. Antibody titers increased with increasing time between symptom onset and the collection of serum collection: MP titers were <1:640 for sera collected after 5.44 days and titers ${\geq}1:640$ for those collected after 8.58 days; P<0.001). Antibody titers were considered positive when they reached ${\geq}1:640$. In 42 MP pneumonia patients in whom there was a four-fold or greater increase in titer between successive serum samples, the optimal cut-off time-point for distinguishing between the initial and second titer groups was 7.5 days after the onset of symptoms (sensitivity, 90.5%; specificity, 92.9%). Conclusions: Negative MP antibody titers earlier than 8 days after the onset of symptoms in children with pneumonia may require repeating to confirm the diagnosis. This finding could optimize diagnosis and result in better therapeutic outcomes of MP pneumonia in children.

• Korean Journal Plant Pathology
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• v.1 no.2
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• pp.101-108
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• 1985

Histopathological changes in the witches'-broom mycoplasma (MLO) infected jujube trees after trunk injection of oxytetracycline HCl (OTC) solution were investigated by using light microscope, fluorescence microscope and electron microscope. In contrast to the healthy leaves, adaxial and abaxial bundle sheath extensions in the major veins of diseased leaves were highly developed, but mesophyll cells were very small, loose and necrosed. In the diseased leaves, excessive phloem was formed, xylem differentiation was supressed and polyphenols were accumulated. Jujube trees treated with 500ml of 2000ppm solution of OTC showed complete remission of witches'-broom symptoms above the injection site, but cells in the sheath extention were hypertrophied and sieve tube necrosis occurred in the secondary phloem of major veins. MLO-specific fluorescence was not observed in the samples of diseased jujube trees treated with OTC, while those from non-treated infectedstress distinctly showed a moderate amount of MLO-specific fluorescence. In the observation under the electron microscope, sieve element of diseased tissues and its associated companion cells were found to have collapsed. Parenchymas cells contained many large starch filled plastids and most samples of diseased and OTC-treated tissues showed an abnormal accumulation of starch compared to the healthy controls. Mycoplasma-like organisms were observed only within mature sieve elements in diseased tissues, but never in OTC-treated tissues.

• Microbiology and Biotechnology Letters
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• v.46 no.1
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• pp.85-90
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• 2018

Sexually transmitted infections (STIs) are a global health concern and can cause serious complications such as miscarriage, premature birth, and pelvic infection in pregnant women. Therefore, accurate diagnosis and information on the epidemiologic trends are critical. However, studies of STI trends in Cheonan, South Korea, have not been conducted since 2012. We examined the STI trends in the Cheonan area after 2012. From January 2011 to September 2017, 3,362 cervical swab specimens from female patients were sampled at the Dankook University Hospital and analyzed by multiplex PCR. Of the 3,362 specimens, 1,281 were positive for pathogens (38.92%). A total of 1,893 pathogens were detected. Ureaplasma urealyticum, Mycoplasma hominis, and Chlamydia trachomatis were the most frequent pathogens, accounting for 36.29% (687/1,893), 30.16% (571/1,893), and 19.97% (378/1,893) of the pathogen-positive samples, respectively. In the 2009-2012 analysis, M. hominis was identified as the predominant pathogen in STI samples, whereas U. urealyticum was identified as the major pathogen in this study. In many countries, including South Korea and the United States, the rate of STIs is increasing, while a decreasing trend was observed in Cheonan.

• Clinical and Experimental Pediatrics
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• v.58 no.6
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• pp.211-217
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• 2015

Purpose: Mycoplasma pneumoniae (MP) infection is a major cause of respiratory infection in school-aged children. Extrapulmonary manifestations of MP infection are common, but liver involvement has been rarely reported. The aim of this study was to determine the clinical characteristics of MP-associated hepatitis. Methods: This prospective study included 1,044 pediatric patients with MP infection diagnosed serologically with MP IgM at one medical center from January 2006 to December 2012. Eighty of these patients had elevated levels of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT), each greater than 50 IU/L, without any other specific liver disorder and were compared with the 964 children without liver disorders. Results: In total, 7.7% of patients with MP infection had a diagnosis of hepatitis, especially in fall and winter. The ratio of male to female patients was 1.7:1, and the mean age of the patients was 5 years and 5 months. The most common symptoms were cough, fever, and sputum. Anorexia was the most common gastrointestinal symptom, followed by nausea/vomiting, diarrhea, and abdominal pain. Mean levels of AST and ALT were 100.65 IU/L and 118.73 IU/L, respectively. Serum AST/ALT level was normalized within 7.5 days on average without complications. The mean duration of hospitalization (11.3 days) was longer for children with hepatitis than for those without hepatitis (P=0.034). Conclusion: MP-associated hepatitis is not uncommon and has a relatively good prognosis. Therefore, clinicians should be concerned about liver involvement in MP infection but avoid further unnecessary evaluation of hepatitis associated with MP.

• Journal of Life Science
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• v.27 no.6
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• pp.694-701
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• 2017

Mycoplasma genitalium represents the smallest genome among mono-cultivable prokaryotes. To discover and compare the orthologs (conservative genes) among M. genitalium and 14 prokaryotes that are uncultivable and have less orthologs than M. genitalium, COG (clusters of orthologous groups of protein) analyses were applied. The analyzed prokaryotes were M. genitalium, one hyperthermophilic exosymbiotic archaeon Nanoarchaeum equitans, four intracellular plant pathogenic eubacteria of Candidatus Phytoplasma genus, and nine endosymbiotic eubacteria of phloem- and xylem-feeding insects. Among 367 orthologs of M. genitalium, 284 orthologs were conservative between M. genitalium and at least one other prokaryote. All 15 prokaryotes commonly have 29 orthologs, representing the significance of proteins in life. They belong to 25 translation-related, including 22 ribosomal proteins, 3 subunits of RNA polymerase, and 1 protein-folding-related. Among the 15 prokaryotes, 40 orthologs were only found in all four Candidatus Phytoplasma. The other nine Candidatus, all endosymbionts with insects, showed only a single common COG0539 (ribosomal protein S1), representing the diversity of orthologs among them. These results might provide clues to understand conservative genes in uncultivable prokaryotes, and may be helpful in industrial areas, such as handling prokaryotes producing amino acids and antibiotics, and as precursors of organic synthesis.