• Korean journal of applied entomology
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• v.39 no.3
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• pp.193-197
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• 2000

Wolbachia, vertically transmitted bacterial endosymbionts, is known to induce cytoplasmic incompatibility (CI), parthenogenesis, or feminization in some insect species. The Wolbachia found to exist symbiotically as a non-virulent form in Drosophila melanogaster, however popcorn is a lethal strain of Wolbachia, which causes tissue degeneration and early death of its adult host. Popcorn-infected flies showed the delayed duration of an egg and larvae, and their pupal period and life span reduced. The oviposition and egg-hatching rate of popcorn-infected flies were decreased 15% and 80%, respectiv~ly, compared to those of the normal Wolbachia-infected flies. The pupation and emergence rates of popcorn-infected flies were 67% and 65%, respectively. When popcorn-infected flies were crossed with Wolba-chia-infected flies, and vice versa, both crosses resulted in a significant reduction in egg production, egg¬hatching, pupation, and emergence rate, and their progeny revealed the popcorn syndrome. When popcorn-infected male flies were crossed with uninfected females, popcorn was not detected in their progeny. Popcorn also maternally transmitted in flies, but it did not induce CI and affected on its host life cycle as a virulence.

• KOREAN POULTRY JOURNAL
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• v.51 no.9
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• pp.161-164
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• 2019

• KOREAN POULTRY JOURNAL
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• v.36 no.10 s.420
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• pp.154-155
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• 2004

마이코플라즈마는 양계 산업에 경제적 손실을 임하는 질병중의 하나이다. 그 중에서도 마이코플라즈마 갈리셉티컴(MG, mycoplasma gallisepticum)은 호흡기 질병을 유발하고 산란율을 떨어뜨리며, 마이코플라즈마 시노바에(MS, mycoplasma synoviae)는 호흡기와 관절이상을 가져온다. MG는 MS보다 더 큰 경제적 손실을 입히고 있다. 본 고에서는 MG에 대한 일반 이해와 미국에서의 예방 실태를 알아 본다. MG는 축제를 떠나면 덥고 건조한 조건에서는 불과 몇 시간밖에 생존하지 못하는 유기체이다. MG는 감염 닭과의 직접접촉, 가까운 거리에서는 공기를 통해, 또는 오염된 기구나 작업자들을 통해 수평 감염되거나 종란을 통해 수직감염 된다. MG 감염은 만성호흡기(CRD, Chronic respriatory disease)의 원인이 되는데 특히 어린 병아리와 브로일러에서 그러하다. CRD 즉 만성 호흡기증의 정도는 MG병원성, 전염성 기관지염(IBV, intectious bronchitis virus), 그리고 대장균증과 같은 2차 감염에 의해 더욱 악화 되게 된다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.3 no.1
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• pp.105-109
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• 2000

X-linked agammaglobulinemia (XLA) is a primary inherited B-cell immunodeficiency. The prevalence of neoplastic disease in patients with XLA is approximatedly 0.7%. The most frequent tumor is lymphoreticular malignancy. We report a case of hepatocellular carcinoma (HCC) in a 13-year-old boy with XLA, after probable maternal transmission of hepatitis B virus. The authors consider that the vertical transmission of hepatitis B virus might play an important role in the development of HCC in a child with XLA who could not eliminate hepatitis B virus effectively.

• Pediatric Infection and Vaccine
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• v.26 no.1
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• pp.66-70
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• 2019

Trans-placental neonatal human immunodeficiency virus (HIV) infection is common in Africa; however, it is not yet reported in the Republic of Korea. With the increasing incidence of HIV infection, especially in the reproductive age group, the risk of the vertical transmission of HIV is also increasing. We report the first case of HIV infection acquired in-utero in a newborn in Korea. The baby is growing well with normal development.

• Journal of Yeungnam Medical Science
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• v.9 no.2
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• pp.407-415
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• 1992

Among 85 patients with anti-HCV positive chronic liver disease, only 21.2% have past history of blood transfusion and over half the cases, they do not have any suspicious risk factors for HCV infection, 3 of 85 families show anti-HCV positive family members. On the other hand, 40 of 60 patients with HBsAg positive chronic liver disease show HBsAg positive family members. In Korea, HBV is transmitted mainly through vertical and intrafamilial infection but HCV disease might be rather horizontal and sporadic than vertical. To define the evident source of infection in sporadic hepatitis C, first of all, simple test with high sensitivity and specificity for diagnosis of HCV infection would be needed.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.8 no.1
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• pp.91-95
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• 2005

The familial environment may also play an important role in the epidemiology of HCV infection through vertical and horizontal transmission by infected household members. However, it is still controversial whether familial clustering of HCV occurs. We experienced a case of familial clustering of hepatitis C virus. A 10-year old girl presented with nausea, vomiting and anorexia for a month was diagnosed as hepatitis C. Her mother, grandmother, a maternal aunt and her daughter had contracted with HCV. Her laboratory findings showed AST/ALT 63/122 IU/L, positive anti-HCV Ab and HCV RNA ($3.54{\times}10^5copies/mL$). Pathologic findings of the liver biopsy revealed chronic hepatitis with minimal lobular activity, mild porto-periportal activity and mild portal fibrosis. After treatment with interferon-${\alpha}$ 2b for 6 months, the clinical symptoms and laboratory findings were normalized.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.12 no.1
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• pp.88-92
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• 2009

Although transfusion of blood and plasma products are accepted as the principle means of transmission of HCV, other parenteral methods, such as acupuncture, tattooing needles, piercing, and surgery are possible methods of transmission of HCV. We managed a case of chronic hepatitis C acquired through ear piercing and acupuncture. A 10-year old girl presented with nausea, abdominal pain, and anorexia for 1 month. Her laboratory finding showed the following: AST/ALT, 865/1,290 IU/L; positive anti-HCV Ab; and HCV RNA. One year previously, she was treated with acupuncture for an ankle sprain and 2 years previously, she had her ears pierced. Laboratory findings of family members showed AST/ALT in the normal ranges, and negative anti-HCV Ab and HCV RNA. The pathologic findings of a liver biopsy revealed chronic hepatitis with mild lobular activity, moderate porto-periportal activity, and portal fibrosis. She was treated with pegylated interferon ${\alpha}$-2a and oral ribavirin for 6 months, after which the clinical symptoms and laboratory findings improved.

• 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.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.3
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• pp.181-194
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• 2002

Parasitism is a one-sided relationship between two organisms in which one benefits at the expense of the other. Parasitic dinoflagellates, particularly species of Amoebophrya, have long been thought to be a potential biological agent for controlling harmful algal bloom(HAB). Amoebophrya infections have been reported for over 40 species representing more than 24 dinoflagellate genera including a few toxic species. Parasitic dinoflagellates Amoebophrya spp. have a relatively simple life cycle consisting of an infective dispersal stage (dinospore), an intracellular growth stage(trophont), and an extracellular reproductive stage(vermiform). Biology of dinospores such as infectivity, survival, and ability to successfully infect host cells differs among dinoflagellate host-parasite systems. There are growing reports that Amoebophrya spp.(previously, collectively known as Amoebophrya ceratii) exhibit the strong host specificity and would be a species complex composed of several host-specific taxa, based on the marked differences in host-parasite biology, cross infection, and molecular genetic data. Dinoflagellates become reproductively incompetent and are eventually killed by the parasite once infected. During the infection cycle of the parasite, the infected host exhibits ecophysiologically different patterns from those of uninfected host in various ways. Photosynthetic performance in autotrophic dinoflagellates can be significantly altered following infection by parasitic dinoflagellate Amoebophrya, with the magnitude of the effects over the infection cycle of the parasite depending on the site of infection. Parasitism by the parasitic dinoflagellate Amoebophrya could have significant impacts on host behavior such as diel vertical migration. Parasitic dinoflagellates may not only stimulate rapid cycling of dissolved organic materials and/or trace metals but also would repackage the relatively large sized host biomass into a number of smaller dinospores, thereby leading to better retention of host's material and energy within the microbial loop. To better understand the roles of parasites in plankton ecology and harmful algal dynamics, further research on a variety of dinoflagellate host-parasite systems is needed.