• Title/Summary/Keyword: challenge infection

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Efficacy of alginate microsphere oral vaccine against Miamiensis avidus (Ciliophora: Scuticociliatida) in olive flounder (Paralichthys olivaceus) (알지네이트 코팅 Miamiensis avidus (Ciliophora: Scuticociliatida) 경구백신의 넙치(Paralichthys olivaceus)에 대한 효능평가)

  • Su-Mi Shin;Sung-Ju Jung
    • Journal of fish pathology
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    • v.36 no.2
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    • pp.311-321
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    • 2023
  • The efficacy of the alginate microsphere (Alginate MS) oral vaccine against Miamiensis avidus in olive flounder (Paralichthys olivaceus) was confirmed through challenge infections by both immersion and injection routes. In trial 1, the formalin-inactivated M. avidus coated with alginate, designated as 'IMa+Alginate MS' group, and the IMa group were administered with vaccines mixed with feed, with a total antigen dose of 3.75 × 106 cells/fish. When challenged with immersion infection at five weeks post vaccination, the relative percent survival (RPS) in the IMa+Alginate MS group was 50% (immersed in 50% seawater) and 37.5% (immersed in 100% seawater). The group that received only IMa showed a low survival rate. In trial 2, the antigen was fed mixed with feed at a total dose of 2.38 × 106 cells/fish for 5 days. Two weeks after oral vaccination, fish were intraperitoneally injected for infection. The RPS in the IMa+Alginate MS group was 30.8%, while the IMa-only group showed no vaccine efficacy. At five weeks post vaccination, when subjected to challenge infection by immersion in 50% seawater, the IMa+Alginate MS group recorded a RPS of 42.9%, whereas the IMa group had a RPS of 14.3%. The results of this study indicate that coating M. avidus antigen with alginate can provide higher protection in olive flounder compared to administering the antigen alone.

Antimicrobial surfaces for craniofacial implants: state of the art

  • Actis, Lisa;Gaviria, Laura;Guda, Teja;Ong, Joo L.
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.39 no.2
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    • pp.43-54
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    • 2013
  • In an attempt to regain function and aesthetics in the craniofacial region, different biomaterials, including titanium, hydroxyapatite, biodegradable polymers and composites, have been widely used as a result of the loss of craniofacial bone. Although these materials presented favorable success rates, osseointegration and antibacterial properties are often hard to achieve. Although bone-implant interactions are highly dependent on the implant's surface characteristics, infections following traumatic craniofacial injuries are common. As such, poor osseointegration and infections are two of the many causes of implant failure. Further, as increasingly complex dental repairs are attempted, the likelihood of infection in these implants has also been on the rise. For these reasons, the treatment of craniofacial bone defects and dental repairs for long-term success remains a challenge. Various approaches to reduce the rate of infection and improve osseointegration have been investigated. Furthermore, recent and planned tissue engineering developments are aimed at improving the implants' physical and biological properties by improving their surfaces in order to develop craniofacial bone substitutes that will restore, maintain and improve tissue function. In this review, the commonly used biomaterials for craniofacial bone restoration and dental repair, as well as surface modification techniques, antibacterial surfaces and coatings are discussed.

Protective effect of bacteriophages against Salmonella Typhimurium infection in weaned piglets (이유자돈에서 Salmonella Typhimurium 감염에 대한 박테리오파지의 방어 효능)

  • Kim, Sung-Jae;Kim, Jae-Hoon;Jun, Soo-Yeon;Paik, Hyoung Rok;Han, Jeong-Hee
    • Korean Journal of Veterinary Service
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    • v.37 no.1
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    • pp.35-43
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    • 2014
  • Salmonellosis has caused heavy losses in swine industry and implications for public health. Recently, the urgent problem of antibiotic resistance due to multidrug-resistant Salmonella spp. has been on the rise. The use of host-specific bateriophages as a biocontrol is one possible alternative. In this study, clinical signs, growth performance, quantification and detection of antigen, histopathological changes of gastrointestinal tracts were analyzed comparatively in weaned piglets according to administration of bacteriophages and challenge with Salmonella (S.) Typhimurium. Piglets challenged with S. Typhimurium after administered with bacteriophages showed reduced clinical signs, higher growth performance, lower bacterial shedding, lower quantificational value of antigens in intestines, higher V/C ratio and higher the number of goblet cells in intestines than piglets administered without bacteriophage and challenged with S. Typhimurium. These results indicate that feeding contained with bacteriophages has effect to prevent infection of S. Typhimurium in weaned piglets and suggest that a use of bacteriophage can be considered a valid antibiotic alternative.

Active and Passive Protective Effect of CFC-101 (Pseudomonas Vaccine) in Mice (CFC-101(녹농균 백신)의 능동 및 수동면역 효과)

  • 박완제;조양제;김영지;김제학;박관하;김유삼;함경수
    • Biomolecules & Therapeutics
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    • v.2 no.4
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    • pp.326-330
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    • 1994
  • The treatment of pseudomonal infection is a perplexed problem because of its modest susceptibility to most of the major antibiotics. A novel Pseudomonas vaccine(CFC-101) was prepared from the outer membrane protein fractions of several Pseudomonas strains. In this study, we examined CFC-101's effectiveness in both active and passive immunization models. CFC-101 in mice at 0.2 mg/kg, i.p., given three times at two-day intervals, completely prevented the death caused by Pseudomonas aeruginosa. Antibody titer, in accordance with the protective effect in this active immunization, was elevated to its peak level following three consecutive administrations of CFC-101. Thereafter, antibody titer stayed at a constantly high level. Each outer membrane protein fraction from the four CFC-101 producers, exhibited good cross-protective effects in mouse infection models against different Fisher types of P. aeruginosa. In the passive immunization model, 21~336 $\mu\textrm{g}$/kg of anti-rabbit IgG to CFC-101, when mice being infected with a challenge strain, prevented the Pseudomonhas-induced death up to 60%. Therefore, the preventive effect of CFC-101 was verified in both the active and passive immunization models.

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A diagnostic dilemma in pediatric osteomyelitis: a case report

  • Mandrekar, Pooja Narendra;Gavhane, Sanket;Fernandes, Trishala Bhadauria;Dhupar, Vikas;Dhupar, Anita
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.48 no.2
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    • pp.117-121
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    • 2022
  • Infantile osteomyelitis is a rare disease that is infective in nature and may rapidly turn fatal, as the disease is often misdiagnosed due to its varied presenting signs. Early diagnosis may help in avoiding systemic involvement and permanent deformity. The disease presents with signs of orbital involvement, nasal congestion, and emesis, as well as other standard hallmarks of infection. Furthermore, the maxilla is a highly vascular and porous bone and the occurrence of osteomyelitis in an infant maxilla is highly uncommon. In addition, routine blood work is not suggestive of the presence of this disease. Thus, prompt diagnosis of this condition poses a challenge to surgeons due to the confusing array of symptoms combined with the rarity of the disease. One such case of osteomyelitis of the maxilla in a young child is presented. The dilemma encountered by the surgeon during the diagnosis and treatment of the disease is discussed.

Discordance between Tuberculin Skin Test and Interferon-gamma Release Assays for Diagnosis of Tuberculosis Infection in Korean Children (국내 소아 결핵감염 진단에서의 결핵피부반응 검사와 Interferon-gamma Release Assay (IGRA)의 비교 연구)

  • Yoo, Reenar;Kim, Joon-Il;Kim, Seohee;Lee, Jina
    • Pediatric Infection and Vaccine
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    • v.23 no.1
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    • pp.18-24
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    • 2016
  • Purpose: There is a the great diagnostic challenge in pediatric tuberculosis especially in high burden setting. The purpose of this preliminary study is to evaluate the agreement between tuberculin skin test (TST) and interferon-gamma release assay (IGRA) including T-SPOT$^{(R)}$.TB and QuantiFERON$^{(R)}$-TB Gold (QFT-G) in Korean children. Method: This retrospective study included children and adolescents who visited to Asan Medical Center to evaluate tuberculosis infection using at least two assays of TST, T-SPOT.TB and QFT-G, from January 2014 to April 2015. Results: A total of 20 patients were included, whose median age was 13.3 years (range, 3.8-18.1 years), and all of them had history of BCG vaccination. Eleven patients had underlying diseases including 7 patients with immunosuppressant medication. The concordance rate between T-SPOT.TB and QFT-G was 90%. However, the concordance rate between TST and T-SPOT.TB was 50%, and between TST and QFT-G was 42.9%. Specificity for the diagnosis of tuberculosis infection of T-SPOT.TB, QFT-G, and TST was 93.3%, 86.7%, and 58.3%, respectively. Conclusions: Although there was a discrepancy between TST and IGRA to diagnose tuberculosis, agreement between T-SPOT.TB and QFT-G was relatively high. Further prospective study to validate the clinical usefulness of each assay for immunologic evidence of tuberculosis infection in Korean children will be mandatory.

Macrophage Activation Syndrome Triggered by Herpes Viral Infection as the Presenting Manifestation of Juvenile Systemic Lupus Erythematosus (헤르페스 바이러스 감염으로 발생한 대식 세포 활성 증후군을 첫 증상으로 한 소아 전신 홍반 루푸스)

  • Noh, Ji Hye;Jeong, Do Young;Jeon, In Su;Kim, Hwang Min
    • Pediatric Infection and Vaccine
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    • v.22 no.3
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    • pp.210-215
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    • 2015
  • Macrophage activation syndrome (MAS) is a rare complication in systemic lupus erythematosus (SLE) that can be triggered by infections. Due to the fact that MAS may mimic clinical features of underlying rheumatic disease, or be confused with an infectious complication, its detection can prove challenging. This is particularly true when there is an unknown/undiagnosed disease; and could turn into an even greater challenge if MAS and SLE are combined with a viral infection. A-14-year-old female came to the hospital with an ongoing fever for 2 weeks and a painful facial skin rash. Hepatomegaly, pancytopenia, increased aspartate aminotransferase, elevated serum ferritin and lactate dehydrogenase were reported. No hemophagocytic infiltration of bone marrow was reported. The patient was suspected for hemophagocytic lymphohistiocytosis. Her skin rashes were eczema herpeticum, which is usually associated with immune compromised conditions. With the history of oral ulcers and malar rash, positive ANA and low C3, C4 and the evidence of hemolytic anemia, she was diagnosed as SLE. According to the diagnostic guideline for MAS in SLE, she was diagnosed MAS as well, activated by acute HSV infection. After administering steroids and antiviral agent, the fever and skin rash disappeared, and the abnormal laboratory findings normalized. Therefore, we are reporting a rare case of MAS triggered by acute HSV infection as the first manifestation of SLE.

Phloretin Protects Macrophages from E. coli-Induced Inflammation through the TLR4 Signaling Pathway

  • Chauhan, Anil Kumar;Jang, Mihee;Kim, Yangmee
    • Journal of Microbiology and Biotechnology
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    • v.30 no.3
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    • pp.333-340
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    • 2020
  • Macrophages are the cells of the first-line defense system, which protect the body from foreign invaders such as bacteria. However, Gram-negative bacteria have always been the major challenge for macrophages due to the presence of lipopolysaccharides on their outer cell membrane. In the present study, we evaluated the effect of phloretin, a flavonoid commonly found in apple, on the protection of macrophages from Escherichia coli infection. RAW 264.7 cells infected with standard E. coli, or virulent E. coli K1 strain were treated with phloretin in a dose-dependent manner to examine its efficacy in protection of macrophages. Our results revealed that phloretin treatment reduced the production of nitric oxide (NO) and generation of reactive oxygen species along with reducing the secretion of proinflammatory cytokines induced by the E. coli and E. coli K1 strains in a concentration-dependent manner. Additionally, treatment of phloretin downregulated the expression of E. coli-induced major inflammatory markers i.e. cyclooxygenase-2 (COX-2) and hemeoxygenase-1 (HO-1), in a concentration dependent manner. Moreover, the TLR4-mediated NF-κB pathway was activated in E. coli-infected macrophages but was potentially downregulated by phloretin at the transcriptional and translational levels. Collectively, our data suggest that phloretin treatment protects macrophages from infection of virulent E. coli K1 strain by downregulating the TLR4-mediated signaling pathway and inhibiting NO and cytokine production, eventually protecting macrophages from E. coli-induced inflammation.

Chronologic chrnge of serum IgG antibody response in chickens reinfected with Cryptosporidium baileyi (닭와포자충 재감염닭의 혈청1gG 항체가 추이)

  • Lee, Jae-Gu;Kim, Hyeon-Cheol;Park, Bae-Geun
    • Parasites, Hosts and Diseases
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    • v.34 no.4
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    • pp.255-258
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    • 1996
  • Eight 2-day-old SPF Chickens were each inoculated Orally With 3 Sing1e dose Of 5 × 105 oocysts of Cryptosporinium boilevi. and immunoglobulin G (IgG) antibody responses were chronologically measured by indirect immunofluorescent antibody (IFA) assay. Anti-C. bcileyi IgG antibody levels remained high (1 : 106.67 to 1:512.00) for at least 4 months with 330 days of a detectable period. Ten days after the negative conversion, each chicken was re-challenged with 1 × 107 oocysts of the same species. Subsequent infection in 340-day-old individuals caused sudden elevated IgG antibody levels and the titer peaked on day 28 postchallenge inoculation (PCI), at 1:1.024 with a 65 days of detection period. Chickens in primary infection showed oocyst shedding profiles. but did not exhibit any oocyst shedding before or after experimental reinfection.

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Protective Immunity of 56-kDa Type-Specific Antigen of Orientia tsutsugamushi Causing Scrub Typhus

  • Choi, Sangho;Jeong, Hang Jin;Ju, Young Ran;Gill, Byoungchul;Hwang, Kyu-Jam;Lee, Jeongmin
    • Journal of Microbiology and Biotechnology
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    • v.24 no.12
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    • pp.1728-1735
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    • 2014
  • Scrub typhus, caused by infection with Orientia tsutsugamushi, is a mite-borne zoonotic disease endemic to the Asian-Pacific region. In Korea, the incidence of this disease has increased with climate changes, and over 10,000 cases of infection were reported in 2013. Although this infection is treatable with antibiotics such as doxycycline and azithromycin, an effective prophylactic vaccine against O. tsutsugamushi would be more desirable for preventing scrub typhus in endemic areas. In this study, we investigated the 56-kDa type-specific antigen (TSA56), which is a major outer membrane protein of O. tsutsugamushi, as a vaccine candidate. Intranasal immunization of recombinant TSA56 (rec56) induced a higher level of TSA56-specific IgG than that induced by intramuscular immunization of tsa56-expressing DNA (p56). Both types of immunization induced a cell-mediated immune response to TSA56, as demonstrated by the splenic cell proliferation assay. Mice immunized with p56, followed by rec56 plus heat-labile enterotoxin B subunit from E. coli, had a stronger protection from a homologous challenge with the O. tsutsugamushi Boryong strain than with other combinations. Our preliminary results suggest that an effective human vaccine for scrub typhus can include either recombinant TSA56 protein or tsa56-expressing DNA, and provide the basis for further studies to optimize vaccine performance using additional antigens or different adjuvants.