• IMMUNE NETWORK
• /
• v.6 no.2
• /
• pp.93-101
• /
• 2006

Background: Memory T lymphocytes of the immune system provide long-term protection in response to bacterial or viral infections/immunization. Ag concentration has also been postulated to be important in determining whether T cell differentiation favors effector versus memory cell development. In the present study we hypothesized that naive Ag-specific $CD4^+$ T cells briefly stimulated with different Ag doses at the primary exposure could affect establishment of memory cell pool after secondary immunization. Methods: To assess this hypothesis, the response kinetics of DO11.10 TCR $CD4^+$ T cells primed with different Ag doses in vitro was measured after adoptive transfer to naive BALB/c mice. Results: Maximum expansion was shown in cells primarily stimulated with high doses of ovalbumin peptide $(OVA_{323-339})$, whereas cells in vitro stimulated with low dose were expanded slightly after in vivo secondary exposure. However, the cells primed with low $OVA_{323-339}$ peptide dose showed least contraction and established higher number of memory cells than other treated groups. When the cell division was analyzed after adoptive transfer, the high dose Ag-stimulated donor cells have undergone seven rounds of cell division at 3 days post-adoptive transfer. However, there was very few division in naive and low dose of peptide-treated group. Conclusion: These results suggest that primary stimulation with a low dose of Ag leads to better memory $CD4^+$ T cell generation after secondary immunization. Therefore, these facts imply that optimally primed $CD4^+$ T cells is necessary to support effective memory pool following administration of booster dose in prime-boost vaccination.

• The Journal of Korea Assosiation for Disability and Oral Health
• /
• v.3 no.1
• /
• pp.26-30
• /
• 2007

Leukocyte adhesion deficiency(LAD) is a rare autorecessive defect of phagocytic function resulting from a lack of leukocyte cell surface expression of ${\beta}_2$ integrin molecules(CD 18) that are essential for leukocyte adhesion to endothelial cells and chemotaxis. As a results, patients with LAD suffer from severe bacterial infections and impaired wound healing. A small number of patients with leukocyte adhesion deficiency-1 have a milder defect, with residual expression of CD18. These patients tend to survive beyond infancy; they manifest progressive severe periodontitis, alveolar bone loss, periodontal pocket formation, and partial or total premature loss of the primary and permanent dentitions. In this report, we report on a 7 year old girl with severe oral involvement. The most import focus should be to control infections to reduce the risk for future infection.

• Toxicological Research
• /
• v.16 no.3
• /
• pp.221-227
• /
• 2000

A 6-sulfooxymethylbenzo[a]pyrene (SMBP), the ultimate metabolite of methyl-substituted benzo[a]pyrene (BP), has been found to be carcinogenic in mice. These properties may be attributable to its strong reactivity with cellular macromolecules such as DNA. However, serum and its major constituent albumin attenuated significantly the cytotoxicity and mutagenicity of 5MBP in bacterial and mammalian cell systems. This inhibitory activity of serum against 5MBP-induced cytotoxicity and mutagenicity in Chinese hamster V79 cells appears to be caused by the reduced macromolecular adducts such as DNA and proteins, but serum failed to reduce 5MBP binding to naked calf thymus DNA. A number of proteins in the serum could act as nucleophiles that are able to intercept reactive chemicals through covalent binding. Albumin present in the plasma seems to be one of major components responsible for direct binding with 5MBp, thereby reducing its reactivity to genetic materials. We here determined which fraction is preferential for 5MBP binding through fractionation of 5MBP-treated serum with ammonium sulfate. The albumin-containing fraction had slightly more affinity for 5MBP than the immunoglobulin-containing fraction. Our results indicate that the covalent modification of plasma proteins may reduce 5MBP-induced damage.

• Journal of Plant Biotechnology
• /
• v.45 no.1
• /
• pp.1-8
• /
• 2018

Meiosis is a specialized cell division, essential in most reproducing organisms to halve the number of chromosomes, thereby enabling the restoration of ploidy levels during fertilization. A key step in meiosis is homologous recombination, which promotes homologous pairing and generates crossovers (COs) to connect homologous chromosomes until their separation at anaphase I. These CO sites, seen cytologically as chiasmata, represent a reciprocal exchange of genetic information between two homologous non-sister chromatids. RAD51, the eukaryotic homolog of the bacterial RecA recombinase, plays a central role in homologous recombination (HR) in yeast and animals. Loss of RAD51 function causes lethality in the flowering plant, Arabidopsis thaliana, suggesting that RAD51 has a meiotic stage-specific function that is different from homologous pairing activity.

• Asian-Australasian Journal of Animal Sciences
• /
• v.29 no.9
• /
• pp.1300-1308
• /
• 2016

This study was conducted to evaluate the effects of phytogenic additive and antibiotic growth promoter in laying Japanese quails. One hundred and sixty five quails were divided into three groups of 5 replicates and 11 quails (8 females and 3 males) in each replicate. Treatment 1 was fed control diet, treatment 2 was fed control diet supplemented with 0.05% bacitracin methylene disalicylate as antibiotic growth promoter and treatment 3 was fed control diet supplemented with 0.1% phytogenic feed additive (PFA) for two periods of 3 weeks each from 37 to 42 weeks of age. Results showed that egg production, eggshell strength, eggshell weight, villus height and villus height to crypt depth ratio were significantly (p${\leq}$0.05) increased and feed consumption, feed conversion ratio, albumen, Haugh unit, cholesterol, low-density lipoprotein, alanine transaminase, gamma glutamyltransferase, alkaline phosphatase, high-density lipoprotein, triglyceride, number of goblet cell, crypt depth and intestinal bacterial population of Coliforms, Salmonella and E. coli were significantly (p${\leq}$0.05) decreased in PFA fed group. It is concluded that addition of PFA containing phytomolecules and organic acids as main ingredients could significantly improve the production parameters and the general health of laying quails as an alternative to antibiotic growth promoters.

• Korean Journal of Veterinary Service
• /
• v.37 no.1
• /
• pp.35-43
• /
• 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.

• Korean Journal of Microbiology
• /
• v.27 no.3
• /
• pp.297-303
• /
• 1989

Attempts to isolate the naturally occurring ultra-violet resistant bacteria from environmental sources were made. The isolates, designated No.29, 100, and 107, among numbers of bacterial isolates revealed a remarkable resistance to UV ray, whose degree of resistance in dose/response kinetics was comparable to that of an endospore-former, Bacillus subtilis. In a range of 100-300 $Jm^{-2}$/min of UV irradiation, the isolates exhibited 500-1000 fold resistance compated with E. coli. The isolated appeared to possiss cell-bound pigment of organge or crimson-red. The isolate 29 is spherical in pairs or tetrads, whereas the isolates 100 and 107 are rod. All are Gram-gositive bacteria and seemed to be non-endospore-bearer. A number of biochemical studies pursued on the isolates suggested that they are quite different to each other. Electron microscopic examination and the physiological characters of the isolate 29 suggested that this UV resistant spherical bacterium might be one species of Deinococcus, probably Deinococus radiophilus. Since there is no documents on UV resistant, Gram-positive, non-sporeformer bacillus so far, the isolates 100 and 107 might be turned out as new kinds of UV resistant bacteria occurring in nature by further investigation.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.29 no.1
• /
• pp.9-16
• /
• 1996

In order to understand microbial ecosystem in the fast china sea and Yosu coastal sea horizontal distributions of bacterial flora, Vibrio spp., coliform group, temperature, and salinity in this sea area, were studied 42 sampling stations during 6th-l4th August, 1992. From the results, salinity and temperature were $24.64\~33.78\%_{\circ}$ and $22.53\~29.18^{\circ}C$, respectively. As the open sea far from land goes on, salinity became low while temperature became high. Viable cell counts of bacteral flova, Vibrio spp., and roliform group in Yosu coastal sea water were $1.0\times10^2\~3.0\times10^4/ml,\;0.2\times10\~9.0\times10^3/ml,\;and\;0.3\times10\~3.0\times10^3/ml$ while those of these in the open sea water were $0.4\times10\~2.0\times10^3/ml,\;0.8\times10\~3.0\times10/ml,\;and\;0.9\times10\~1.3\times10/ml$, respectively.

• Korean Journal of Soil Science and Fertilizer
• /
• v.46 no.2
• /
• pp.105-111
• /
• 2013

The experiments were carried out to investigate the biocontrol potential of Lysobacter capsici YS1215 on root-knot nematode and to characterize its lytic enzyme activities. L. capsici YS1215 showed chitinase and gelatinase activities on the medium containing 0.5% chitin or 0.5% gelatin as substrates. Cell growth of L. capsici YS1215 was highest at 6 days, and the highest activities of chitinase (4.0 unit $ml^{-1}$) and gelatinase (7.43 unit $ml^{-1}$) were observed on 3 and 5 days after incubation, respectively. To investigate the effect of L. capsici YS1215 on tomato growth and nematode infection, the plants in pot trial were treated with bacterial culture (BC), half of bacterial culture (HBC), only bacterial medium (BM), tap water (TW) and commercial nematicide (CN). HBC treatd plants showed the higher shoot fresh weight and dry weight on $5^{th}$week after incubation while BM, HBC and BC had consistently higher values than TW at $9^{th}$ week. HBC appeared to be the highest shoot fresh length at $9^{th}$ week. Both CN and BC showed lower number of egg mass, root gall, and population of juveniles in soil compared to BC, HBC, BM and TW. These results suggest that L. capsici YS1215 with its strong ability of lytic enzyme production can be one of the most significant candidates for biocontrol agents against root-knot nematodes.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.15 no.2
• /
• pp.98-108
• /
• 2007

In order to use food wastes for the source of fermented feed for pigs, this study was aimed to produce better culture inoculum by the aeration and addition of pig' s blood meal as sub nutrient. For the preparation of inoculum as bacterial strain, Lactobacillus brevis isolated from pig intestine, and a yeast Saccharomyces cerevisiae from strawberries were used. Molasses and whey were used as main ingredients for the culture solution as well as yeast extract and other ingredients as sub nutrients. As the experimental result, aeration showed a positive effect to enhance viable cell count or retarding death phase. Although sub nutrient yeast extracts were replaced with pig's blood meal, fermentation characteristics were almost similar to that of yeast extract. When the inoculum was stored at room temperature, L. brevis and S. cerevisiae maintained the viable cell concentration of approximately 8 log cfu/mL for 1 week. 2 Days after the culture solution was mixed with food waste, the number of unwanted bacteria had rapidly increased, but E.coli was not detected for 5 days.