The oral microbiota is associated with oral diseases and digestive systemic diseases. Nevertheless, the causal relationship between them has not been completely elucidated, and colonisation of the gut by oral bacteria is not clear due to the limitations of existing research models. The aim of this study was to develop a human oral microbiota-associated (HOMA) mouse model and to investigate the ecological invasion into the gut. By transplanting human saliva into germ-free (GF) mice, a HOMA mouse model was first constructed. 16S rRNA gene sequencing was used to reveal the biogeography of oral bacteria along the cephalocaudal axis of the digestive tract. In the HOMA mice, 84.78% of the detected genus-level taxa were specific to the donor. Principal component analysis (PCA) revealed that the donor oral microbiota clustered with those of the HOMA mice and were distinct from those of specific pathogen-free (SPF) mice. In HOMA mice, OTU counts decreased from the stomach and small intestine to the distal gut. The distal gut was dominated by Streptococcus, Veillonella, Haemophilus, Fusobacterium, Trichococcus and Actinomyces. HOMA mice and human microbiota-associated (HMA) mice along with the GF mice were then cohoused. Microbial communities of cohoused mice clustered together and were significantly separated from those of HOMA mice and HMA mice. The Source Tracker analysis and network analysis revealed more significant ecological invasion from oral bacteria in the small intestines, compared to the distal gut, of cohoused mice. In conclusion, a HOMA mouse model was successfully established. By overcoming the physical and microbial barrier, oral bacteria colonised the gut and profiled the gut microbiota, especially in the small intestine.
Animals ; Bacteria ; Gastrointestinal Microbiome ; Germ-Free Life ; Humans ; Mice ; Microbiota ; RNA, Ribosomal, 16S

OBJECTIVEProtein of Streptococcus mutans is considered as one of the virulence factors due to its ability to mediate the initial attachment of Streptococcus mutans to tooth surface. In this study, an anticaries DNA vaccine pCIA-P was used to immunize rats. The expression of PAc in different tissues in vivo, specific immune response and protection effects against dental caries were observed.

METHODSPlasmid pCIA-P was injected into rats by two different routs: intramuscular injection (i.m.) and targeted salivary gland immunization (TSG). Immunohistochemistry technique was used to detect the expression of PAc. Gnotobiotic rats were vaccinated with pCIA-P by three different approaches: TSG, intramuscular injection and buccal mucosal injection (i.o.). The specific immune responses were evaluated by ELISA and their anticaries effects were evaluated by Keyes caries scores.

RESULTSPAc was expressed in the sarcoplasm and sarcolemma of muscle fibers and submandibular glands, especially strongly positive in duct regions. The levels of serum specific anti-PAc IgG and salivary specific anti-PAc IgA in TSG immunization and buccal mucosal immunization group were significantly higher than those of other groups. The Keyes caries scores of those two groups were significantly lower than those of other groups.

CONCLUSIONThe plasmid pCIA-P could provoke specific immune responses as a novel immunogen. Mucosal immunization with pCIA-P appears to be an effective genetic immunization method against dental caries.

Animals ; Antibodies, Bacterial ; blood ; Bacterial Proteins ; genetics ; immunology ; Dental Caries ; prevention & control ; Germ-Free Life ; Immunization ; Male ; Membrane Glycoproteins ; Rats ; Rats, Wistar ; Streptococcal Vaccines ; immunology ; Streptococcus mutans ; immunology ; Vaccines, DNA ; immunology

PURPOSE: We investigated whether a relationship exists between tumor control dose 50 (TCD50) or tumor growth delay (TGD) and radiation induced apoptosis (RIA) in syngeneic murine tumors. Also we investigated the biological markers that can predict radiosensitivity in murine tumor system through analysis of relationship between TCD50, TGD, RIA and constitutive expression levels of the genetic products regulating RIA. MATERIALS AND METHODS: Syngeneic murine tumors such as ovarian adenocarcinoma, mammary carcinoma, squamous cell carcinoma, fibrosarcoma, hepatocarcinoma were used in this study. C3H/HeJ mice were bred and maintained in our specific pathogen free mouse colony and were 8~12 weeks old when used for the experiments. The tumors, growing in the right hind legs of mice, were analyzed for TCD50, TGD, and RIA at 8 mm in diameter. The tumors were also analyzed for the constitutive expression levels of p53, p21(WAF1/CIP1), BAX, Bcl-2, Bcl-x(L), Bcl-x(S), and p34. Correlation analysis was performed whether the level of RIA were correlated with TCD50 or TGD, and the constitutive expression levels of genetic products regulating RIA were correlated with TCD50, TGD, RIA. RESULTS: The level of RIA showed a significant positive correlation (R=0.922, p=0.026) with TGD, and showed a trend to correlation (R=-0.848), marginally significant correlation with TCD50 (p=0.070). It indicates that tumors that respond to radiation with high percentage of apoptosis were more radiosensitive. The constitutive expression levels of p21(WAF1/CIP1) and p34 showed a significant correlation either with TCD50 (R=0.893, p=0.041 and R=0.904, p=0.035) or with TGD (R=-0.922, p=0.026 and R=-0.890, p=0.043). The tumors with high constitutive expression levels of p21(WAF1/CIP1) or p34 were less radiosensitive than those with low expression. CONCLUSION: Radiosensitivity may be predicted with the level of RIA in murine tumors. The constitutive expression levels of p21(WAF1/CIP1) or p34 can be used as biological markers which predict the radiosensitivity.
Adenocarcinoma ; Animals ; Apoptosis ; Biomarkers* ; Carcinoma, Squamous Cell ; Fibrosarcoma ; Leg ; Mice ; Radiation Tolerance* ; Specific Pathogen-Free Organisms

We have investigated and discussed the changes of scholarship, tuition and educational facilities in national medical colleges and private medical colleges for the period of 1984 and 1993. The data an alysed in this study were cited from the third edition and the seventh edition and raw data for the eighth edition of the Educational State Report of Korean Medical Schools which were issued by the Deans' Association of Korean Medical Schools. The significant findings were as follows: 1. In all investigated medical college libraries, the number of seats and medical books and the sorts of medical journals have increased, particularly the average budgets for medical journals have increased over 3 times in 1993 compare to 1994. 2. Between 1984 and 1993, total budget for scholarship have been increased out average benefit rate have been decreased from 38.6% to 34.3%. But the average benefit doubled its amount. 3. Average tuition in national medical college was about 52% of that in private medical college in 1993. In national medical colleges, average tuition for premedical course was 10% costly than medical course but it was just opposite to private medical colleges. 4. Between 1984 and 1993, Audio-visual aids have increased in number a little bit but there was nothing significant changes between national and private medical college. 5. Eighty one percent of investigated medical colleges have animal laboratory for research but only 15.6% of medical colleges have specific pathogen free rooms in the animal laboratories. 6. In 1993, the space in medical college buildings was occupied 29.6% by student education facilities, 25.8% by research space for professors and 10.5% by medical library. The average area for student educations was 42.4m2, for professors research was 32.2m2 and for library was 11.4m2 per a student.
Animals ; Audiovisual Aids ; Budgets ; Education ; Fellowships and Scholarships* ; Humans ; Libraries, Medical ; Schools, Medical ; Specific Pathogen-Free Organisms

Avian influenza (AI) is an infectious, low pathogenic virus that is endemic all over the world and poses a potential threat to the poultry industry. Vaccination is a widely used effective method to prevent avian influenza virus. Here we employed a comparative proteomics approach [two-dimensional electrophoresis (2-DE) and matrix assisted laser desorption ionization-time of flight (MALDI-TOF)] to characterize proteome in the sera from the specific pathogen free (SPF) chickens, the vaccinated chickens, and the naturally infected chickens. We identified total 58 proteins that were differentially expressed in the sera of three groups. Among them ovotransferrin and vitamin D-binding protein were more expressed in the sera of naturally infected chickens compare with other groups. Our results suggested that the level of these two proteins in the serum may help to discriminate the naturally infected chicken from the vaccinated chicken.
Animals ; Chickens ; Conalbumin ; Electrophoresis ; Influenza in Birds ; Poultry ; Proteins ; Proteome ; Proteomics ; Specific Pathogen-Free Organisms ; Vaccination ; Viruses ; Vitamin D-Binding Protein

We analyzed 72 items related to serum biochemistry and hematology in 85 specific pathogen-free (SPF) Seoul National University (SNU) miniature pigs aged 1- to 36-months which originated from a Minnesota miniature pig. Almost all examined items were similar between male and female pigs. However, some items such as Cr level, B/C ratio, C.R.F, LDH, LAP and T4 were significantly different between male and female pigs (P<0.05). Thirty four examined items showed age-related changes, and the significant changes were observed in animals less than six months old. The values for BUN, K, uric acid, Ca, Ca++, and Pi were significantly higher in pigs younger than six months of age, which might reflect poor kidney function in young pigs. Additionally, TIBC, UIBC and RDW were significantly higher in young pigs, and RBC, Hb, HCT, MCHC and MCV were significantly lower in young pigs, thus indicating a similar physiology of iron deficiency anemia. These age-related specific phenotypes seemed to be normal, but it should be considered in the long-term experiment using the young pigs. In conclusion, in this study, we defined the normal reference intervals for SPF SNU miniature pigs, and we also determined that there are some physiological differences between the pig genders and ages. This study provides fundamental data for use in experiments involving SPF SNU miniature pigs.
Aged ; Anemia, Iron-Deficiency ; Animals ; Biochemistry ; Female ; Hematology ; Humans ; Kidney ; Male ; Minnesota ; Phenotype ; Specific Pathogen-Free Organisms ; Swine ; Uric Acid

In Korea, several outbreaks of low pathogenic AI (H9N2) viral infections leading to decreased egg production and increased mortality have been reported on commercial farms since 1996, resulting in severe economic losses. To control the H9N2 LPAI endemic, the Korea Veterinary Authority has permitted the use of the inactivated H9N2 LPAI vaccine since 2007. In this study, we developed a killed vaccine using a low pathogenic H9N2 AI virus (A/chicken/Korea/ADL0401) and conducted safety and efficacy tests in commercial layer farms while focusing on analysis of factors that cause losses to farms, including egg production rate, egg abnormality, and feed efficiency. The egg production rate of the control group declined dramatically 5 days after the challenge. There were no changes in feed consumption of all three groups before the challenge, but rates of the control declined afterward. Clinical signs in the vaccinated groups were similar, and a slight decline in feed consumption was observed after challenge; however, this returned to normal more rapidly than the control group and commercial layers. Overall, the results of this study indicate that the safety and efficacy of the vaccine are adequate to provide protection against the AI field infection (H9N2) epidemic in Korea.
Animals ; Chickens ; Emulsions ; Female ; Influenza A Virus, H9N2 Subtype/*immunology ; Influenza Vaccines/*immunology/*standards ; Influenza in Birds/immunology/prevention & control ; Oviparity ; Specific Pathogen-Free Organisms ; Vaccines, Inactivated/immunology

Despite the existence of an active vaccination program, recently emerged strains of nephropathogenic infectious bronchitis virus (IBV) in Korea have caused significant economic losses in the poultry industry. In this study, we assessed the pathogenic and antigenic characteristics of a K-IIb type field strain of IBV that emerged in Korea since 2003, such as Kr/Q43/06. Specific pathogen free 1-week-old chickens exhibited severe respiratory symptoms (dyspnea) and nephropathogenic lesions (swollen kidneys with nephritis and urate deposits) following challenge with the recent IBV field strain. The antigenic relatedness (R value), based on a calculated virus neutralization index, of the K-IIb type field strain and K-IIa type strain KM91 (isolated in 1991) was 30%, which indicated that the recent strain, Kr/Q43/06, is a new variant that is antigenically distinct from strain KM91. This report is the first to document the emergence of a new antigenic variant of nephropathogenic IBV in chicken from Korea.
Animals ; Antigens, Viral ; *Chickens ; Coronavirus Infections/epidemiology/*veterinary/virology ; Infectious bronchitis virus/classification/*pathogenicity ; Korea ; Nephritis/*veterinary/virology ; Poultry Diseases/*virology ; Specific Pathogen-Free Organisms ; Virulence

One-day-old SPF chicks were inoculated with the Cux-l strain of chicken infectious anemia virus (CIAV), and the clinical development of disease and its macroscopic and microscopic alterations in the thymus and bone marrow, were observed. Tissue sections of thymus and bone marrow were stained using the streptavidin-biotin peroxidase method and examined under light microscope for evaluation of antigenic intensities in tissues. Those findings were then compared with blood parameters and ELISA results obtained through collected sera during sacrifice procedures. We sought to determine: the localization of viral antigens in thymus and bone marrow tissues after inoculation, the correlation between antigen intensities and hematologic, serologic and histopathologic findings, definitive diagnostic criteria using histopathologic and immunoperoxidase methods, and the reliability of these methods in the diagnosis of CIAV infection. For this purpose, 83, one-day-old SPF chicks were used. The birds were divided into experimental (n = 52) and control (n = 26) groups. A virus dose of TCID50 of 100,000/ml was administered intramuscularly to every bird in the experimental group. Based on the results of this study, we have suggested that clinical examination, along with macroscopic and microscopic evaluation of the thymus and bone marrow, maybe undertaken starting from day 7 post-inoculation (PI). ELISA, might be of value, as it might give consistent results starting from day 14 PI. However, the most reliable results were obtained through examination of thymus and bone marrow sections from infected birds stained by immunoperoxidase technique, as early as day 4 PI.
Animals ; Bone Marrow/*pathology ; *Chicken anemia virus ; Chickens ; Circoviridae Infections/pathology/*veterinary ; Immunoenzyme Techniques ; Poultry Diseases/*pathology ; Specific Pathogen-Free Organisms ; Thymus Gland/*pathology

Infectious bursal disease virus (IBDV) causes a highly contagious and immunosuppressive disease of chicken. Agar gel immunodiffusion using IBDV antigen extracted from bursa of Fabricius of infected chicken has been used officially for diagnosis of IBDV in Korea. In this study, in order to replace the IBDV whole virus antigen with non-infectious antigen, recombinant VP2 protein (rVP2) of IBDV was produced using recombinant baculovirus expression system. Purified baculovirus-expressed rVP2 was used as an antigen in an agar gel immunodiffusion (AGID). rVP2 antigen precipitated specifically IBDV antibodies. AGID using rVP2 antigen detected anti-IBDV antibodies from 6 dpi to 28 dpi (termination of the experiment) when specific pathogen free chickens were experimentally infected with IBDV 52/70 strain. This was consistent with result by AGID using IBDV antigen, virus neutralization test (VNT) and a commercial ELISA kit (except for one serum). The sensitivity of rVP2 was the same with that of IBDV antigen when field sera (n=324) were tested by AGID. However, AGID using rVP2 antigen detected maternal antibodies from broiler chickens (n=20) on a broiler farm up to 15 days old, although the detection rate of the AGID was relatively low compared to a commercial ELISA kit. Our results indicate that IBDV whole virus antigen from IBDV infected chickens would be replaced with recombinant VP2 protein as an antigen for AGID.
Agar ; Animals ; Antibodies ; Baculoviridae ; Bursa of Fabricius ; Chickens ; Enzyme-Linked Immunosorbent Assay ; Immunodiffusion ; Infectious bursal disease virus ; Korea ; Neutralization Tests ; Specific Pathogen-Free Organisms ; Sprains and Strains ; Staphylococcal Protein A ; Viruses