Tissue Fluid Enzyme-Linked Immunosorbant Assay for Piglets Experimentally Infected with Toxoplasma gondii and Survey on Local and Imported Pork in Korean Retail Meat Markets

To investigate the prevalence of Toxoplasma gondii in pork on the market in Korea, an in-house enzyme-linked immunosorbent assay for tissue fluid (CAU-tf-ELISA) was developed using a soluble extract of T. gondii RH strain tachyzoites. As the standard positive controls, the piglets were experimentally infected with T. gondii: Group A (1,000 cysts-containing bradyzoites), Group B (500 cysts-containing bradyzoites) and Group C (1.0×103 or 1.0×104 tachyzoites). The CAU-tf-ELISA demonstrated infection intensity-dependent positivity toward tissue fluids with average cut-off value 0.15: 100% for Group A, 93.8% for Group B and 40.6% for Group C. When tissue-specific cut-off values 0.066–0.199 were applied, CAU-tf-ELISA showed 96.7% sensitivity, 100% specificity, 100% positive and 90.0% negative predictive values. When compared with the same tissue fluids, performance of CAU-tf-ELISA was better than that of a commercial ELISA kit. Of the 583 Korea domestic pork samples tested, anti-T. gondii antibodies were detected from 9.1% of whole samples and 37.9% from skirt meat highest among pork parts. In the 386 imported frozen pork samples, 1.8% (skirt meat and shoulder blade) were positive for anti-T. gondii antibodies. In Korea, prevalence of anti-T. gondii antibodies in the pork on retail markets appeared high, suggesting that regulations on pig farming and facilities are necessary to supply safe pork on the tables.

Efficacy of silver ions against Sacbrood virus infection in the Eastern honey bee Apis cerana

Although silver is known to be a broad-spectrum biocidal agent, the effects of this metal against Sacbrood virus have not yet been investigated. In this study, we evaluated the efficacy of silver ions against natural Korean sacbrood virus (KSBV) infection of Apis (A.) cerana. Ten KSBV-infected colonies containing A. cerana with similar strength and activity were selected from an apiary located in Bosung-gun (Korea). Among these, five colonies were randomly assigned to the treatment group that was fed sugar syrup containing 0.2 mg/L silver ions. The other colonies were assigned to the untreated control group in which bees were given syrup without the silver ions. To assess the efficacy of the silver ions, colony strength, colony activity, and the number of dead larvae per hive were measured. During the experimental period, the test group maintained its strength and activity until day 32 while those of bees in the control group decreased sharply after day 8 to 16. Survival duration of the test group was significantly longer (40 days) than that of the control group (21 days). These results strongly indicated that silver ions are effective against KSBV infection in A. cerana.

Molecular Prevalence of Acarapis Mite Infestations in Honey Bees in Korea

Acarapis mites, including Acarapis woodi, Acarapis externus, and Acarapis dorsalis, are parasites of bees which can cause severe damage to the bee industry by destroying colonies and decreasing honey production. All 3 species are prevalent throughout many countries including UK, USA, Iran, Turkey, China, and Japan. Based on previous reports of Acarapis mites occurring in northeast Asia, including China and Japan, we investigated a survey of Acarapis mite infestations in honey bees in Korean apiaries. A total of 99 colonies of Apis mellifera were sampled from 5 provinces. The head and thorax of 20 bees from each colony were removed for DNA extraction. PCR assays were performed with 3 primer sets, including T, A, and K primers. Results indicated that 42.4% (42/99) of samples were Acarapis-positive by PCR assay which were sequenced to identify species. Each sequence showed 92.6-99.3% homology with reference sequences. Based on the homology, the number of colonies infected with A. dorsalis was 32 which showed the highest infection rate among the 3 species, while the number of colonies infected with A. externus and A. woodi was 9 and 1, respectively. However, none of the Acarapis mites were morphologically detected. This result could be explained that all apiaries in the survey used acaricides against bee mites such as Varroa destructor and Tropilaelaps clareae which also affect against Acarapis mites. Based on this study, it is highly probable that Acarapis mites as well as Varroa and Tropilaelaps could be prevalent in Korean apiaries.

Isolation, characterization, and evaluation of Bacillus thuringiensis isolated from cow milk / 대한수의학회지

Probiotics colonize the intestines and exert an antibacterial effect on pathogens. Therefore, probiotics could be used as a preventive agent against lethal infections. To isolate probiotic microorganisms, 116 bacterial strains were isolated from healthy cow's milk and were subjected to Gram-stain, morphology and biochemical analyses, Vitek analysis, and 16S rRNA analysis. One of the strains identified as Bacillus (B.) thuringiensis 87 was found to grow very well at pH 4.0~7.0 and to be resistant to high concentrations of bile salts (0.3~0.9% w/v). B. thuringiensis was susceptible to the antibiotics used in the treatment of bovine mastitis, yet it exhibited an antimicrobial effect against Staphylococcus (S.) aureus 305. Moreover, it protected mice from experimental lethal infections of E. coli O55, Salmonella typhimurium 01D, and S. aureus 305 through a significant induction of interferon-gamma, even at four-week post-administration of B. thuringiensis. Although oral administration of B. thuringiensis 87 did not provide significant protection against these lethal challenges, these results suggest that B. thuringiensis 87 could be a feasible candidate as a probiotic strain.

Protective efficacy of vaccination with Neospora caninum multiple recombinant antigens against experimental Neospora caninum infection

Protective efficacy of vaccination with Neospora caninum multiple recombinant antigens against N. caninum infection was evaluated in vitro and in vivo. Two major immunodominant surface antigens (NcSAG1 and NcSRS2) and two dense granule proteins (NcDG1 and NcDG2) of N. caninum tachyzoites were expressed in E. coli, respectively. An in vitro neutralization assay using polyclonal antisera raised against each recombinant antigen showed inhibitory effects on the invasion of N. caninum tachyzoites into host cells. Separate groups of gerbils were immunized with the purified recombinant proteins singly or in combinations and animals were then challenged with N. caninum. Following these experimental challenges, the protective efficacy of each vaccination was determined by assessing animal survival rate. All experimental groups showed protective effects of different degrees against experimental infection. The highest protection efficacy was observed for combined vaccination with NcSRS2 and NcDG1. Our results indicate that combined vaccination with the N. caninum recombinant antigens, NcSRS2 and NcDG1, induces the highest protective effect against N. caninum infection in vitro and in vivo.

Capsular polysaccharide typing of domestic mastitis-causing Staphylococcus aureus strains and its potential exploration of bovine mastitis vaccine developmen. I. capsular polysaccharide typing, isolation and purification of the strains

One hundred seven isolates of Staphylococcus aureus from bovine mastitis were investigated for colony morphology in serum-soft agar (SSA), autoagglutination in salt, and capsular serotype. Capsular polysaccharide (CP) was purified and quantified from the extracts of clinical isolates. Overall, 89 isolates (83.2%) were diffuse in the SSA, without any difference in the proportion of diffuse colony between type 5 and type 8 strains. Some strains exhibited compact colonies in the SSA and expressed CP as determined by an enzyme-linked immunosorbent assay, indicating that compact morphology does not exclude encapsulation. The majority of the strains (11/12) showed autoagglutination in the salt aggregation test. The serotype 336 accounted for 46.7% of the isolates followed by serotype 5 (12.1%) and serotype 8 (12.1%). Particularly, twenty-six (24.3%) isolates reacted with two serotypes; 7 for type 8/336 and 19 for type 5/336. Five isolates (4.7%) were nontypeable with monoclonal antibodies specific for CP serotype 5, 8, or 336. The CP concentration in culture supernatants varied with the serotypes, and the total amount of CP produced by cells grown in a liquid medium was much less than that produced by cells grown on a solid medium. The Western blotting indicated that the CP bands of S. aureus serotype 5 and 8 were ranged in the molecular mass of 58-84 kilodalton (kDa), with additional bands in the region of approximately >or= 48 or

A Survey of Hepatitis B Virus Markers by EIA Method among Steel Manufacturing Workers / 대한산업의학회지

A study for seroprevalence of Hepatitis B virus markers (HBsAg, Anti-HBs, HBeAg and Anti-HBe) by EIA method and the Liver Function Test(SGOT and SGPT) using kinetic method was carried :out from January; to October 1995 :among male workers of a .major iron and steel manufacturing company, located,,in Pohang. The results were as follows; 1. The distribution of hepatitis B virus markers showed that the proportions of HBsAg(+)/Anti-HBs (-), HBsAg(-)/Anti-HBs (+) 'and HBsAg(+)/Anti-HBs (+) were 8.1%, 60.5% and 0.1%, respectively. The positive rate of HBsAg in all subjects was 8.2% whereas that of anti-HBs was 60.6%. 2. The proportions of HBsAg(+)/Anti-HBs (-) and HBsAg(-)/Anti-HBs (+) increased significantly with age. While the distribution of hepatitis B virus markers exhibited no significant differences among the groups classified by educational background or work type. 3. The proportion of drinkers in HBsAg (+)/Anti-HBs (-) (73; 9%) was significantly lower than those of HBsAg (-)/Anti-HBs (-) and HBsAg (-)/Anti-HBs (+) (84.6% and 85.7% respectively). The proportions of smoking for the three groups of HBsAg (-)/Anti-HBs(+),-HBsAg (+)/Anti-HBs (-) and HBsAg (-)/Anti-HBs (-) were 54.3%, 53.7% and 53.0%, respectively (p<0.01). The proportion of the subjects with abnormal liver function test in HBsAg (+)/Anti-HBs (-) was 40.1%, whereas those in HBsAg (-)/Anti-HBs (-) and HBsAg(-)/Anti-HBs (+) were 21.9% and 18.4%, respectively. 4. The distribution of e Ag markers among HBsAg (+) subjects showed that the proportions of HBeAg(+)/Anti-HBe(-), HBeAg(-)/Anti-HBe(+) and HBeAg(+)/Anti-HBe(+) were 31.3%, 55.0% and 1.6%, respectively. The proportion of HBeAg(+)/Anti-HBe(-) decreased significantly with age and those of HBeAg(-)/Anti-HBe(-) and HBeAg(-)/Anti-HBe(+) increased with age. The positive rate of HBeAg among HBsAg (+) subjects was 32.9%. In conclusion, as a screening method, EIA is. recommended to test hepatitis B virus markers, especially when examining Anti-HBs more sensitively. For the workers of the iron and steel manufacturing company studied, liver diseases caused by other than hepatitis B should be given a special care including an education avoiding alcohol drinking.

A Survey of Hepatitis B Virus Markers by EIA Method among Steel Manufacturing Workers / 대한산업의학회지

A study for seroprevalence of Hepatitis B virus markers (HBsAg, Anti-HBs, HBeAg and Anti-HBe) by EIA method and the Liver Function Test(SGOT and SGPT) using kinetic method was carried :out from January; to October 1995 :among male workers of a .major iron and steel manufacturing company, located,,in Pohang. The results were as follows; 1. The distribution of hepatitis B virus markers showed that the proportions of HBsAg(+)/Anti-HBs (-), HBsAg(-)/Anti-HBs (+) 'and HBsAg(+)/Anti-HBs (+) were 8.1%, 60.5% and 0.1%, respectively. The positive rate of HBsAg in all subjects was 8.2% whereas that of anti-HBs was 60.6%. 2. The proportions of HBsAg(+)/Anti-HBs (-) and HBsAg(-)/Anti-HBs (+) increased significantly with age. While the distribution of hepatitis B virus markers exhibited no significant differences among the groups classified by educational background or work type. 3. The proportion of drinkers in HBsAg (+)/Anti-HBs (-) (73; 9%) was significantly lower than those of HBsAg (-)/Anti-HBs (-) and HBsAg (-)/Anti-HBs (+) (84.6% and 85.7% respectively). The proportions of smoking for the three groups of HBsAg (-)/Anti-HBs(+),-HBsAg (+)/Anti-HBs (-) and HBsAg (-)/Anti-HBs (-) were 54.3%, 53.7% and 53.0%, respectively (p<0.01). The proportion of the subjects with abnormal liver function test in HBsAg (+)/Anti-HBs (-) was 40.1%, whereas those in HBsAg (-)/Anti-HBs (-) and HBsAg(-)/Anti-HBs (+) were 21.9% and 18.4%, respectively. 4. The distribution of e Ag markers among HBsAg (+) subjects showed that the proportions of HBeAg(+)/Anti-HBe(-), HBeAg(-)/Anti-HBe(+) and HBeAg(+)/Anti-HBe(+) were 31.3%, 55.0% and 1.6%, respectively. The proportion of HBeAg(+)/Anti-HBe(-) decreased significantly with age and those of HBeAg(-)/Anti-HBe(-) and HBeAg(-)/Anti-HBe(+) increased with age. The positive rate of HBeAg among HBsAg (+) subjects was 32.9%. In conclusion, as a screening method, EIA is. recommended to test hepatitis B virus markers, especially when examining Anti-HBs more sensitively. For the workers of the iron and steel manufacturing company studied, liver diseases caused by other than hepatitis B should be given a special care including an education avoiding alcohol drinking.

Characterization of the high mannose asparagine-linked oligosaccharides synthesized by microfilariae of Dirofilaria immitis

this report describes the structures of high-mannose-type N-linked oligosaccharides in glycoproteins synthesized by the microfilariae of Dirofioria immitis. Microfilariae of D. immitis were incubated in vitro in media contaning 2-[(3)H] mannose to allow metabolic radiolabeling of the oligosaccharide moieties of newly synthesized glycoproteins. Glycopeptides were prepared from the radiolabeled glycoproteins by digestion with pronase and fractionation by chromatography on concanavalin A-Sepharose. Thirty eight percent of 2-[(3)H] mannose incorporated into the microfilariae of D. immitis glycopeptides was recovered in high mannose-type asparagine-linked oligosaccharides whech were bound to the immobilized lectin. Upon treatment of 2-[(3)H] mannose labeled glycopeptides with endo-beta-N-acetylglucosaminidase H, the high mannose-type chains were released and their structures were determined by high performance liquid chromatography and exoglycosidase digestion. The major species of high mannose-type chains synthesized by microfilariae of D. immitis have the composition Man(5) GlcNAc(2), Man(6) ClcNAc(2), Man(8) GlcNA(2), and Man(8) GlcNAc(2). Structural analyses indicate that these oligosaccharides are similar to high mannose-type chains synthesized by vertebrates.

A case of congenital Pelger-Huet anomaly

No abstract available.

Classification of Frequently Occurring Disease by Chief Camplaints in Rural Area / 예방의학회지

In Korea, the Regional differences of medical facilities and man-powers are very serious recently. In order to solve rural medical problem, the comprehensive health care service is required earnestly in rural area. The present study was performed to provide the material for rural medical policy by analyzing the diseases occurring frequently in rural area and assuming the paramedical workers' abilities of medical treatment. The frequently by occurring diseases were classified by investigation. The chief complaints of 4559 subjects through home visiting for last weeks occurred in 1978. The paramedical workers' abilities of medical treatment were investigated by analyzing the clinical charts of patients treated by paramedical workers by systemic health care delivery system from September 1977 to December 1977. The results obtained are summarized as follows; 1. The rate of disease suffering recently for 2 weeks was 22.5% in rural area. 2. The rate of respiratory disease was 36.0%, gartrointestinal disease 18%, trauma 8% and neuromuscular disease 7.5%, respectively. 3. The coverage of treatment by health workers was 97.6% in general practitioner, 70% in community health practitioner and 42.1% in community health aid, respectively.