• Clinical and Experimental Pediatrics
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• v.50 no.7
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• pp.698-701
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• 2007

We report on two premature infants who developed nosocomial infection caused by Chryseobacterium meningosepticum in a neonatal intensive care unit (NICU). One premature infant developed sepsis, meningitis, and hydrocephalus, and was treated successfully with ciprofloxacin plus trimethoprim-sulfamethoxazole combination therapy for 4 weeks and with a ventriculoperitoneal shunt. The other premature infant, who was in a chronically debilitated state, had infection that had colonized only in the respiratory tract but had no clinical signs for 66 days. Extensive environmental surveillance demonstrated that the suction bottle apparatus was the source of infection. We prevented the spread of infection by closing the NICU temporarily, isolating the patients early in their infection, and eradicating the source of infection source.

• Clinical and Experimental Pediatrics
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• v.49 no.2
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• pp.136-143
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• 2006

The relationship between H. pylori(Hp) infection and recurrent abdominal pain(RAP) in children is not clear. Current data in the literature regarding a causal relationship between Hp infection and childhood RAP are conflicting. However, meta-analysis and most of the recently published studies have not supported an association between Hp infection and an increased prevalence of abdominal pain. Most published studies have some problems and have been criticized on methodological grounds. Most of the existing studies have not been designed to include double-blind placebo controls. And, because of the low incidence of Hp infection in children, they have a problem of obtaining sufficient numbers of the Hp infected children. There is also a concern about the heterogeneity of testing methodology in the studies and diagnostic accuracy problems of the non-invasive tests such as low sensitivity of the serology tests and false positive results of the UBT in children. And conflicting results may be explained, in part, by the poor definition of RAP or dyspepsia for the study subjects. To date, no consensus exists for the treatment of Hp-infected children with RAP. Some authors suggest the clinical efficacy of Hp. But others suggest that eradication of Hp is not associated with improvement of RAP. The problem of the most treatment studies is that they had usually no control groups and the number of the subjects was small. In order to make reasonable decisions about treatment of Hp infection in children with RAP, long-term, randomized, double blind, well controlled studies in large numbers of children will be required.

• Parasites, Hosts and Diseases
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• v.51 no.1
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• pp.69-74
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• 2013

Leishmania tropica is one of the causative agents of leishmaniasis in humans. Routes of infection have been reported to be an important variable for some species of Leishmania parasites. The role of this variable is not clear for L. tropica infection. The aim of this study was to explore the effects of route of L. tropica infection on the disease outcome and immunologic parameters in BALB/c mice. Two routes were used; subcutaneous in the footpad and intradermal in the ear. Mice were challenged by Leishmani major, after establishment of the L. tropica infection, to evaluate the level of protective immunity. Immune responses were assayed at week 1 and week 4 after challenge. The subcutaneous route in the footpad in comparison to the intradermal route in the ear induced significantly more protective immunity against L. major challenge, including higher delayed-type hypersensitivity responses, more rapid lesion resolution, lower parasite loads, and lower levels of IL-10. Our data showed that the route of infection in BALB/c model of L. tropica infection is an important variable and should be considered in developing an appropriate experimental model for L. tropica infections.

• Parasites, Hosts and Diseases
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• v.21 no.2
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• pp.224-233
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• 1983

An experimental study was carried out to observe the susceptibility of several kinds of laboratory animals to Fibricola seoulensis infection, a diplostomatid fluke of mammals. The metacercariae were obtained from the viscera of the snakes, Natrix tigrina lateralis and 50~2,000 in number each was artificially fed to a total of 127 animals; albino rats, mice, dogs, cats, rabbits and chickens. After 3 days to 8 weeks the animals were sacrificed and the recovery rate of worms as well as their maturity was observed. The results are as follows: 1. The overall worm recovery rates throughout the experimental period was highest in albino rats (40.0%) followed by mice (33.9%), cats (20.9%), dogs (11.4%), rabbits (0.05%) and chickens (0%). However, the recovery rates in the same host decreased as infection progressed longer and variable by the amount of metacercariae given. 2. From albino rats and mice, the highest recovery rates were obtained in 1,000 and 200-metacercariae infection groups respectively, and it is considered that such amount should be the optimum dose for experimental infection of these animals. 3. The main location of F. seoulensis in experimental animals was small intestine especially the duodenum. 4. The maturity index (No. mature worms/ No. examined) was 100% in albino rats and mice, while only 22.7% or 0% in dogs or cats respectively. From the results, it is concluded that albino rats and mice are the most susceptible hosts for F. seoulensis infection among six kinds of laboratory animals examined.

• Journal of Life Science
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• v.20 no.9
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• pp.1294-1298
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• 2010

White spot syndrome virus (WSSV) is one of the most virulent viral agents threatening the penaeid shrimp culture industry. This study was carried out to evaluate the susceptibility of the sand shrimp, Crangon affinis, to WSSV as an alternative experimental model. WSSV caused 100% mortality in C. affinis within 7 days after experimental infection by immersion. Based on challenge studies, it was confirmed that C. affinis could be a potential host in WSSV transmission. Also, the neutralization of WSSV was carried out using an antiserum raised against recombinant envelop protein rVP466 to evaluate the WSSV infection mechanism. A constant amount of WSSV (at $1{\times}10^4$ diluted stocks) was incubated with various amounts of antiserum and then mixed to 20 l reservoir for the immersion challenge of C. affinis for neutralization. At 5 days post challenge, the shrimp in the positive control immersed in the immersion reservoir containing WSSV stock showed 100% mortality. The shrimps challenged with the 3 different mixtures of WSSV and rVP466 antiserum (1:0.1, 1:0.5 and 1:1) showed 100%, 68.8% and 68.8% mortality at 14 days post challenge, respectively. These results indicated that the antiserum raised against rVP466 could block WSSV infection in C. affinis. Therefore, this study confirmed that C. affinis can be naturally infected by WSSV as another potential host and that C. affinis can be used as an alternative experimental animal instead of penaeid shrimps.

• Parasites, Hosts and Diseases
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• v.33 no.1
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• pp.37-44
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• 1995

Neodiplostomum seoulensis, one of the human intestinal trematodes , was reinfected to albino rats, and worm recovery rates, histopathology and activity changes of the intestinal brush border membrane bound enzymes were observed. The experimental groups were three: uninfected, primary infection and reinfection. The worm recovery rate in the reinfection group was much lower than in the primary infection group 14 days after infection. The duodenal histopathology showed villous atrophy during the first and second week in the primary infection group. In the reinfection group, however. villous changes occurred as early as 3 days after the infection, and the lesion was found healed 7 days after infection. The activities of alkaline phosphatase and sucrase in the duodenum of primary infection rats decreased nearly half of the controls 2 weeks after infection, whereas the activities were unchanged in the reinfection group. However, no changes in the activities were observed in the proximal jejunum between the experimental groups. These findings suggested that a secondary infection of N. seouLensis in rats should make less damage on the intestinal mucosa than a primary infection. Key words: Neoniplostomum seoulensis, albino rats, reinfection, worm recovery, histopathology, brush border membrane bound enxyines.

• Clinical and Experimental Pediatrics
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• v.59 no.7
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• pp.285-291
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• 2016

That rotavirus infection can cause neurological symptoms in young children has been well established. However, it is surprising why rotavirus infection has been overlooked as a cause of neonatal seizures for many years, despite significant research interest in neonatal rotavirus infection. Neonates are the age group most vulnerable to seizures, which are typically attributed to a wide range of causes. By contrast, because rotavirus infection is usually asymptomatic, it has been difficult to identify an association between this virus and neonatal seizures. The conventional wisdom has been that, although neonates are commonly infected with rotavirus, neurological complications are rare in this age. However, recent studies using diffusion-weighted imaging (DWI) have suggested a connection between rotavirus infection and neonatal seizures and that rotavirus infection can induce diffuse white matter injury without direct invasion of the central nervous system. The clinical features of white matter injury in rotavirus-infected neonates include the onset of seizures at days 4-6 of life in apparently healthy term infants. The recent findings seem to contradict the conventional wisdom. However, white matter injury might not be a completely new aspect of rotavirus infection in neonates, considering the forgotten clinical entity of neonatal seizures, 'fifth day fits'. With increased use of DWI in neonatal seizures, we are just starting to understand connection between viral infection and white matter injury in neonates. In this review, we discuss the historical aspects of rotavirus infection and neonatal seizures. We also present the clinical features of white matter injury in neonatal rotavirus infection.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2647-2655
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• 2015

This study has the purpose to evaluate the effects of cooperative learning applying Jigsaw model in simulation based infection control education by comparing perception of infection control, intrinsic motive and learning satisfaction, 54 first-year health related students. It is composed of 27 students of the experimental group and 27 students of the control group. In order to evaluate the homogeneity between the two groups, it surveyed in advance perception of infection control, intrinsic motive and learning satisfaction. There was no significant difference between the two groups, The education program composed cooperative learning applying Jigsaw Model, simulation practice and debriefing to the experimental group was performed twice for 2 weeks and lecture and skill training, simulation practice and debriefing were performed to the control group. After two-week education, perception of infection control, intrinsic motive and learning satisfaction of the participants the research were surveyed. As a result of this study, the Jigsow Model indicated the perception of infection control and learning satisfaction experimental group was significantly high in statistic. Based on this research result, I suggests that utilization of cooperative learning applying the Jigsaw Model as a strategy to improve the scholatic achievement and learning satisfaction of students in the variable simulation based education.

• Korean Journal of Ichthyology
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• v.28 no.3
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• pp.141-146
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• 2016

Experimental infection of rainbow trout Oncorhynchus mykiss with viral hemorrhagic septicemia virus (VHSV, genotype IVa) from olive flounder Paralichtys olivaceus was examined. The cumulative mortalities of three different lot of rainbow trout fry challenged with VHSV ($10^{6.3-7.3}TCID_{50}$/fish) were less than 15%. No difference of virulence was observed in experimental infection using 5 in vivo passaged VHSV and original VHSV. No mortality was observed in seawater-reared rainbow trout (adult) challenged with VHSV ($10^{5.3-6.3}TCID_{50}$/fish) and virus was not detected in the fish. We thus concluded that VHSV from olive flounder has low virulence to rainbow trout fry, but not pathogenic to seawater-rainbow trout (adult).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.4
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• pp.628-636
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• 2020

Streptococcosis in the olive flounder Paralichthys olivaceus can be caused by Streptococcus parauberis. We compared three routes of administration for experimental injections of the S. parauberis 19FBSPa0003 strain in the olive flounder. Pathological changes were observed during the experimental infection. Inflammation of the serous membrane in the liver, intestine, spleen and heart was the major pathological change found in the infected olive flounder. No mortality was observed in fish that received intraperitoneal (IP) injection at less than 1×10⁴ colony-forming unit (CFU)/fish. The lethal dose 50 for olive flounder, given an intravenous (IV) injection, was 7.94×10⁴ CFU/fish. Fish with a higher concentration of IV injected S. parauberis (1×10⁸ CFU/fish) died within a maximum of two days. However, serious necrosis and bacterial proliferation in ellipsoidal cells of the spleen and heart tissues were found in moribund or dead fish, 1-2 days after IV injection. Similar histopathological signs were observed in olive flounder inoculated by subcutaneous (SC) infected and naturally infected. In addition, SC was also strongly associated with bacteria concentration and cumulative mortality rate. Based on these results, SC is the recommended method for artificial infection by S. parauberis in the olive flounder.