• Parasites, Hosts and Diseases
• /
• v.61 no.3
• /
• pp.231-239
• /
• 2023

Toxoplasma gondii is an intracellular parasitic organism affecting all warm-blooded vertebrates. Due to the unavailability of commercialized human T. gondii vaccine, many studies have been reported investigating the protective efficacy of pre-clinical T. gondii vaccines expressing diverse antigens. Careful antigen selection and implementing multifarious immunization strategies could enhance protection against toxoplasmosis in animal models. Although none of the available vaccines could remove the tissue-dwelling parasites from the host organism, findings from these pre-clinical toxoplasmosis vaccine studies highlighted their developmental potential and provided insights into rational vaccine design. We herein explored the progress of T. gondii vaccine development using DNA, protein subunit, and virus-like particle vaccine platforms. Specifically, we summarized the findings from the pre-clinical toxoplasmosis vaccine studies involving T. gondii challenge infection in mice published in the past 5 years.

• Korean Journal of Radiology
• /
• v.21 no.5
• /
• pp.537-540
• /
• 2020

Recently, some global cases of 2019 novel coronavirus (COVID-19) pneumonia have been caused by second- or third-generation transmission of the viral infection, resulting in no traceable epidemiological history. Owing to the complications of COVID-19 pneumonia, the first symptom and imaging features of patients can be very atypical and early diagnosis of COVID-19 infections remains a challenge. It would aid radiologists and clinicians to be aware of the early atypical symptom and imaging features of the disease and contribute to the prevention of infected patients being missed.

• Journal of Oral Medicine and Pain
• /
• v.49 no.2
• /
• pp.35-39
• /
• 2024

Osteomyelitis of the jaw is an inflammatory process of the bone marrow that is caused by odontogenic local infection and trauma such as tooth extraction and fractures in the oral and maxillofacial region. The clinical signs include pain, swelling, pus formation, and limited mouth opening. Chronic osteomyelitis presents a diagnostic challenge because of the variability of symptoms across different disease stages and varying health conditions of the patients. This report presents a case of osteomyelitis that was misdiagnosed as a temporomandibular joint disorder (TMD) after tooth extraction. The patient was treated for inflammation after tooth extraction in the early stage; however, as the osteomyelitis progressed chronically, symptoms mimicked those of a TMD. The patient was finally diagnosed with osteomyelitis 6 months after tooth extraction. A review of this case and relevant literature revealed the necessity for a differential diagnosis of chronic osteomyelitis that mimics TMD symptoms.

• Asian-Australasian Journal of Animal Sciences
• /
• v.27 no.7
• /
• pp.981-989
• /
• 2014

The objective of the present study was to investigate the effects of a mixture of functional oils (Essential, Oligo Basics Agroind. Ltda) on performance response of chickens challenged with coccidiosis and the determination of apparent metabolizable energy (AME), nitrogen-corrected apparent metabolizable energy (AMEn), the coefficients of protein and ether extract digestibility and intestinal morphology of broilers fed with diets containing Essential. In Exp. 1, a completely randomized design (CRD) was used, with one control diet without Essential inclusion with coccidiosis (Eimeria acervulina, Eimeria maxima, and Eimeria tenella) challenged birds and two different inclusion rates of Essential (1.5 kg/ton and 2 kg/ton) with coccidiosis-challenged and non-challenged birds for each inclusion rate, using 10 replicates and 50 birds per experimental unit. After 7 d of coccidiosis challenge, the livability was approximately 10% lower (p<0.05) for the control group. Intestinal lesion scores were lower (p<0.05) in the anterior intestine and the cecum for the chickens supplemented. Feed efficiency and growth rate were improved in birds supplemented with Essential (p<0.05) before the coccidiosis challenge and during the first 7 d post infection. In Exp. 2, a CRD was used, with one control diet without Essential inclusion and one diet with inclusion of Essential (1.5 kg/ton), using nine replications and 33 chicks per pen. The diets with Essential yielded approximately 4% higher AME (p = 0.003) and $AME_n$ (p = 0.001). Essential supplementation increased villus height in the jejunum on d 14 (p<0.05). Villus height:crypt depth ratio for the supplemented birds was larger (p<0.05) in the jejunum on d 7, larger (p<0.05) in the jejunum and ileum on d 14. In conclusion, these functional oils improved the energy utilization and the livability and decreased lesions caused by coccidiosis in supplemented birds.

• Korean Journal of Veterinary Research
• /
• v.53 no.4
• /
• pp.211-216
• /
• 2013

This study was focusing on evaluating the protection of polyphosphate kinase (ppk) deleted and/or temperature-sensitive (ts) Salmonella Enteritidis (SE) as an attenuated vaccine in chickens. We constructed SEppk, SEts and SEppk::ts mutants and screened those mutants by growth capability in vitro, protection study in mice model and antibody response in chickens. Among the mutants, SEppk::ts-3 was selected because it showed higher growth capability, good protection against highly virulent SE in mice model, and good antibody response in chickens. SEppk::ts-3 also showed good protection against highly virulent SE isolate because it decreased colonization of virulent SE challenge strain in spleen, liver and cecum compared with the non-vaccinated control. The SEppk::ts-3 mutant showed cross-protection against S. Gallinarum (SG) challenge although the its cross-protection rate was a little lower than that of SG9R, a commercial vaccine against SG infection. To use for live attenuated vaccine in chickens, it should further be characterized.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.10
• /
• pp.1761-1767
• /
• 2015

Sevenband grouper, Epinephelus septemfasciatus, is becoming an important aquaculture species in Korea. However, viral nervous necrosis disease is a large problem causing mass mortality in sevenband grouper aquaculture. Recombinant protein vaccines are one of the best methods to reduce these economic losses. However, the cell-based expression method mainly produces inclusion bodies and requires additional procedures. In this study, we expressed a recombinant viral coat protein of sevenband grouper nervous necrosis virus (NNV) using a cell-free protein synthesis system. The purified recombinant NNV coat protein (rNNV-CP) was injected into sevenband grouper at different doses followed by a NNV challenge. Nonimmunized fish in the first trial (20 μg/fish) began to die 5 days post-challenge and reached 70% cumulative mortality. In contrast, immunized fish also starting dying 5 days postchallenge but lower cumulative mortality (10%) was observed. Cumulative morality in the second trial with different doses (20, 4, and 0.8 μg/fish) was 10%, 40%, and 50%, respectively. These results suggest that rNNV-CP can effectively immunize sevenband grouper depending on the dose administered. This study provides a new approach to develop a recombinant vaccine against NNV infection for sevenband grouper.

• Korean Journal of Veterinary Research
• /
• v.48 no.2
• /
• pp.167-174
• /
• 2008

Lactic acid bacteria have been reported their beneficial roles on host including reduction of infectious diarrhea problems. In this study, preventive effect of Lactobacillus (L.) reuteri HY25101 and L. johnsonii HY25103 on porcine epidemic diarrhea virus (PEDV) was investigated in suckling piglets. Two groups of one day old PEDV naïve piglets were orally administered L. reuteri HY25101 and L. johnsonii HY25103 for three days respectively before challenge with lethal dose of PEDV. In second experiment, passive immunized one day old piglets using colostrums containing PEDV specific IgA were used. The survival rates of the L. reuteri HY25101 administered group were significantly higher than that of L. johnsonii HY25103 administered group and viral shedding was rapidly diminished in L. reuteri HY25101 administered group. Interestingly piglets born from the sow immunized with attenuated PEDV vaccine were not completely protected from PEDV challenge, however coadministeration of L. reuteri HY25101 and colostrums containing PEDV specific IgA were more effectively prevent PEDV infection. These results suggested that dietary treatment using L. reuteri HY25101 could reduce diarrheal problem and mortality rate caused by PEDV in suckling pigs. In addition, L. reuteri HY25101 could be used as one of effective compensation treatment with attenuated live vaccine for PED.

• Korean Journal of Veterinary Research
• /
• v.51 no.2
• /
• pp.151-158
• /
• 2011

The study evaluated whether a transgenic carrot vaccine could induce a K88-specific immune response in sows and whether the resultant maternal antibody could protect piglets against enterotoxigenic Escherichia coli (ETEC) K88ac infection. Sows (n = 15) selected randomly from a farm in Korea were assigned to three groups (n = 5 per group: control [untreated]), group A (orally inoculated with a nontransgenic and transgenic carrot vaccines at 2 and 4 weeks ante partum, respectively), and group B (conventionally vaccinated according to the manufacturer's instructions). After 7 days of lactation, 5 piglets selected randomly from each group were challenged with $1{\times}10^{10}$ colony forming units/mL ETEC K88ac. Group C had the lowest mean fecal consistency score on post-challenge days 1 and 7. Histiologically, On post-challenge day 7, group C showed an increased duodenum and ileum villus:crypt ratio, compared to group A in the duodenum, with group B displaying the highest ratio. Groups B and C had more increased villus width than group A in the jejunum. Group C displayed the greatest increase in villus width in the ileum. The colostrums and serum from groups B and C displayed higher concentrations of IgA and IgG against ETEC K88, compared to group A. Based on the results, it was concluded that the transgenic carrot vaccine in sow per oral may have an effect on preventing piglet diarrhea as good as commercial recombinant vaccine.

• Journal of fish pathology
• /
• v.34 no.1
• /
• pp.1-7
• /
• 2021

Red sea bream iridovirus (RSIV), belonging to the genus Megalocytivirus, is the predominant cause of mortality in marine fishes in Korea, including rock bream (Oplegnathus fasciatus). Rockfish (Sebastes schlegelii) are the host fish for RSIV, exhibiting no clinical signs or mortality. Cohabitation challenges, which mimicked natural transmission conditions, were performed to evaluate viral transmission between rock bream and rockfish, and to determine the pathogenicity and viral loads. In cohabitation challenge, artificially RSIV-infected rock bream were the viral donor, and healthy rockfish were the recipient. The results showed that although the donor rock bream had 95-100 % cumulative mortality (>10⁸ viral genome copies/mg of spleen 7-14 days after viral infection), the recipient rockfish did not die, even when the viral genome copies in the spleen were >10⁵ copies/mg. These results indicated asymptomatic infections. Notably, in a reverse-cohabitation challenge (artificially RSIV-infected rockfish as the viral donor and healthy rock bream as the recipient), RSIV horizontally infected from subclinical rockfish to rock bream (10⁷ viral genome copies/mg of spleen 21 days after cohabitation) with 10-20% cumulative mortality. These results suggest that an asymptomatic, infected rockfish can naturally transmit the RSIV without being sacrificed.

• Korean Journal of Veterinary Service
• /
• v.44 no.4
• /
• pp.291-297
• /
• 2021

Severe outbreaks of porcine epidemic diarrhoea virus (PEDV) have continued to re-emerge worldwide. Because of the high mortality rate of suckling piglets in PEDV outbreaks, the disease causes significant economic losses in the pig industry. The limited pre-existing immunity against this virus is thought to cause an explosive increase in infection in pig farms. This study aimed to evaluate the clinical symptoms of PEDV after intentional exposure (feedback). During the first few days of the outbreak in a breeding pig farm, 14 sows showed watery diarrhoea, and the disease subsequently spread rapidly throughout the barn. Pigs that were intentionally exposed to PEDV (n=251) showed watery diarrhoea (46.6%), reduced appetite (17.5%), and vomiting (6.0%). However, 75 exposed pigs (29.9%) showed no clinical signs of disease. Four weeks after the feedback challenge, 34 sows gave birth to litters of piglets, which survived with no diarrhoea. Five weeks after the start of the outbreak, PEDV was not detected in any of the examined samples, including environmental swabs. Thus, early diagnosis, prompt establishment of herd immunity, and strict application of biosecurity are good practices to reduce the mortality rates among new-born piglets and control economic losses in pig farms showing PEDV outbreaks.