• Korean Journal of Veterinary Research
• /
• v.10 no.2
• /
• pp.21-51
• /
• 1970

Series of experiments were conducted to determine lethal does of X-ray and Neutron on Toxoplasma gondii. strain RH and IRI. As well morphological changes of Toxoplasma gondii irradiated or not were compared by use of electron microscope. The pathogenicity test of the irradiated and nonirradiated Toxoplasma gondii was made in mice guinea-pigs, rabbits and pigs: The letahl dose of X-ray and Neutron on RH and IRI strain and the growth rate between two strains after irradiation were shown little differences. Morphological changes were not observed until 18th passage was made. After then, the growth rate was decreased apparently, and atrophied forms were frequently observed in electron microscope. Survival time of animals inoculated with irradiated strain was longer than that of animals giving non-irradiated strain, and Toxoplasma gondii were isolated from all the dead animals. But it is of interest that pigs survived after injection of Toxoplasma gondii remained health and much attempts were failed toisolate Toxplasma gondii remained health and much attempts were slaughtered them. Animals were succumbed after injection of Toxoplasma gondii without any relationship with serum titers. (HA antibody).

• International Journal of Oral Biology
• /
• v.35 no.4
• /
• pp.209-214
• /
• 2010

Cells that have endogenous multipotent properties can be used as a starting source for the generation of induced pluripotent cells (iPSC). In addition, small molecules associated with epigenetic reprogramming are also widely used to enhance the multi- or pluripotency of such cells. Skinderived precursor cells (SKPs) are multipotent, sphereforming and embryonic neural crest-related precursor cells. These cells can be isolated from a juvenile or adult mammalian dermis. SKPs are also an efficient starting cell source for reprogramming and the generation of iPSCs because of the high expression levels of Sox2 and Klf4 in these cells as well as their endogenous multipotency. In this study, valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, was tested in the generation of iPSCs as a potential enhancer of the reprogramming potential of SKPs. SKPs were isolated from the back skins of 5-6 week old C57BL/6 X DBA/2 F1 mice. After passage 3, the SKPs was treated with 2 mM of VPA and the quantitative real time RT-PCR was performed to quantify the expression of Oct4 and Klf4 (pluripotency specific genes), and Snai2 and Ngfr (neural crest specific genes). The results show that Oct4 and Klf4 expression was decreased by VPA treatment. However, there were no significant changes in neural crest specific gene expression following VPA treatment. Hence, although VPA is one of the most potent of the HDAC inhibitors, it does not enhance the reprogramming of multipotent skin precursor cells in mice.

• Journal of Veterinary Science
• /
• v.22 no.4
• /
• pp.56.1-56.10
• /
• 2021

Background: Fluorescent antibody virus neutralization (FAVN) test is a standard assay for quantifying rabies virus-neutralizing antibody (VNA) in serum. However, a safer rabies virus (RABV) should be used in the FAVN assay. There is a need for a new method that is economical and time-saving by eliminating the immunostaining step. Objectives: We aimed to improve the traditional FAVN method by rescuing and characterizing a new recombinant RABV expressing green fluorescent protein (GFP). Methods: A new recombinant RABV expressing GFP designated as ERAGS-GFP was rescued using a reverse genetic system. Immuno-fluorescence assay, peroxidase-linked assay, electron microscopy and reverse transcription polymerase chain reaction were performed to confirm the recombinant ERAGS-GFP virus as a RABV expressing the GFP gene. The safety of ERAGS-GFP was evaluated in 4-week-old mice. The rabies VNA titers were measured and compared with conventional FAVN and FAVN-GFP tests using VERO cells. Results: The virus propagated in VERO cells was confirmed as RABV expressing GFP. The ERAGS-GFP showed the highest titer (10^8.0 TCID₅₀/mL) in VERO cells at 5 days post-inoculation, and GFP expression persisted until passage 30. The body weight of 4-week-old mice inoculated intracranially with ERAGS-GFP continued to increase and the survival rate was 100%. In 62 dog sera, the FAVN-GFP result was significantly correlated with that of conventional FAVN (r = 0.95). Conclusions: We constructed ERAGS-GFP, which could replace the challenge virus standard-11 strain used in FAVN test.

• International Journal of Oral Biology
• /
• v.37 no.4
• /
• pp.175-180
• /
• 2012

Skin-derived precursor cells (SKPs) are multipotent, sphere-forming and embryonic neural crest-related precursor cells that can be isolated from dermis. It is known that the properties of porcine SKPs can be enhanced by leukemia inhibitory factor (LIF) which is an essential factor for the generation of embryonic stem cells in mice. In our present study, to enhance or maintain the properties of murine SKPs, LIF was added to the culture medium. SKPs were treated with 1,000 IU LIF for 72 hours after passage 3. Quantitative real time RT-PCR was then performed to quantify the expression of the pluripotent stem cell specific genes Oct4, Nanog, Klf4 and c-Myc, and the neural crest specific genes Snai2 and Ngfr. The results show that the expression of Oct4 is increased in murine SKPs by LIF treatment whereas the level of Ngfr is decreased under these conditions. Interestingly, LIF treatment reduced Nanog expression which is also important for cell proliferation in adult stem cells and for osteogenic induction in mesenchymal stem cells. These findings implicate LIF in the maintenance of stemness in SKPs through the suppression of lineage differentiation and in part through the control of cell proliferation.

• Korean Journal of Pharmacognosy
• /
• v.25 no.4 s.99
• /
• pp.348-355
• /
• 1994

An antitumor component, F-D-P, was purified from the hot water extract of the carpophores of Elfvingia applanata by precipitation with ethanol, dialysis, and passage through a column of DEAE-cellulose ion exchange. F-D-P inhibited the growth of Sarcoma 180 in mice showing the tumor inhibition ratio of 88.3% in doses of 20 mg/kg for ten days. Chemical analysis of F-D-P showed that it was composed of polysaccharide(65.3%) and protein(6.5%0, and that the monosaccharides consisting of the polysaccharide was glucose(89.1%) and mannose(10.9%). The immunomodulatory activities of F-D-P were explored by determining its effect on the proliferation of the whole and subpopulations of lymphocytes, and on the generation of natural killer(NK) cell activity in vitro. F-D-P was mitogenic to total lymphocytes and B cells, but not to purified T cells, even in the presence of accessory cells. F-D-P did not increase NK cell activity when added to cultures of resting lymphocytes. From these results, it is clear that F-D-P modulates primarily the humoral immune responeses.

• The Journal of Korean Medicine
• /
• v.27 no.1 s.65
• /
• pp.146-154
• /
• 2006

Objectives : Siguan points (LI4, LR3) have been most frequently applied for various diseases, especially different digestive disorders such as constipation, abdominal pain or various intestinal inflammatory diseases. The fact that gastrointestina movement is closely connected with physiologic functions or pathologic process of alimentary canal led us to ask the question if Siguan points affects on intestinal motility. Design: To investigate the effect of Siguan acupuncture on the intestinal movement in both physiologic and pathologic conditions, we divided the experimental animals into 12 groups. Six groups were pre-treated with loperamide (0.5 mg/kg, sc) or scoploamine (0.5 mg/kg, sc) to suppress the intestinal movement and another three groups were pretreated with carbachol (0.5 mg/kg, po) to activate it, whereas the rest three groups didn't receive any pretreatment to be kept in the physiological condition. After the administration with charcoal meal, mice were acupunctured bilaterally on sham point or Siguan points as the manner of tap-stimulation, with the exception of no acupuncture groups. Methods : Mice were scarified in twenty minutes after the administration of charcoal to measure the distance of charcoal passage from stomach-duodenal junction. The effect on intestinal movement was presented by calculating the relative distance where charcoal arrived to total length of small intestine. Results : In physiological state, charcoal meal passed around 53%, and there was no significant difference between Siguan points and sham points groups. On the other hand. Siguan points-sitimulation significantly ameliorated loperamide or scoplolamine-induced suppressed travel rate of 17.3 % and 18.6% in sham point into 26% and 26.3% respectively (p<0.05). In carbachol-induced accelerated condition, Siguan points-stimulation didn't affect intestinal motility comparing to sham point group passed about 97.6%. Conclusions : These results postulate that acupuncture at Siguan points have a therapeutic effect by restoring cholinergic activity on pathogenically suppressed intestinal peristalsis, but does not affect the gastrointestinal motility in the normal or accelerated condition.

• Journal of Food Hygiene and Safety
• /
• v.26 no.3
• /
• pp.222-226
• /
• 2011

Salmonellosis is a major bacterial zoonosis that causes self-limited enteritis to fatal infection in animals and food-borne infection and typhoid fever in humans. Multidrug-resistant strains of Salmonella spp. has increased over the last several decades and recently causes more serious problems in public health. The present study was investigated bacteriocidal effects of sodium chlorate, sodium azide, sodium cyanide, and sodium salts mixture containing sodium chlorate, sodium azide, and sodium cyanide on infection with S. typhimurium in macrophage RAW 264.7 cells, and antibacterial effects of sodium salts mixture for murine salmonellosis. In infection assay of S. typhimurium in RAW 264.7 cells, bacterial survival rates within macrophage in all treated groups was significantly reduced comparing to that of the control group with the passage of incubation time. Administration of sodium salts mixture showed a therapeutic effect for S. typhimurium infected ICR mice. The mortality of mice treated with sodium salts mixture was 70% until 12 days, while that of control mice was 100% until 9 days after S. typhimurium infection. The results of this study strongly indicate that sodium salts mixture has a potency treatment for murine salmonellosis.

• Clinical and Experimental Reproductive Medicine
• /
• v.35 no.1
• /
• pp.39-48
• /
• 2008

Objective: The aim of this study was to investigate whether multipotent germline stem cells (MGSCs) can be established from neonatal mouse testis. Methods: Various cells containing MGSCs were collected from neonatal testis of ICR mice and allocated to plates for in vitro culture. After 7 days in culture, the cells were passed to a fresh culture plate and continuously cultured. From the third or fourth passage, the presumed MGSCs were cultured and maintained on mitomycin C-inactivated STO feeder cells. The MGSCs were cultured in a condition where mouse embryonic stem cells (ESCs) are cultured. Characteristics of the MGSCs were evaluated by RT-PCR, immunocytochemistry, alkaline phosphatase activity, karyotyping, and transmission electron microscopy. Results: Two MGSCs lines were established from 9 pooled sets of neonatal testicular cells. MGSCs colonies were morphologically undistinguishable from ESCs colonies and both MGSC lines as well as ESCs expressed undifferentiated stem cell markers, such as Thy-1, Oct-4, Nanog, Sox2 and alkaline phosphatase. Fine structure of undifferentiated MGSCs were similar to those of ESCs and 60% of MGSCs (12/20) had normal karyotype at passage 10. They were able to form embryoid bodies (EBs) and MGSC-derived EBs expressed marker genes of three germ layers. Conclusion: We could establish the MGSCs from neonatal mouse testis and they were differentiated to multipotent lineages of three germ layers. Molecular characteristics of MGSCs were similar to those of ESCs. Our results suggest a possibility that multipotent stem cells derived from testis, the MGSCs, could replace the ESCs in biotechnology and regenerative medicine.

• Journal of Veterinary Science
• /
• v.25 no.3
• /
• pp.36.1-36.15
• /
• 2024

Importance: The intravenous administration of adipose tissue-derived mesenchymal stem cells (AdMSCs) in veterinary medicine is an attractive treatment option. On the other hand, it can result in severe complications, including pulmonary thromboembolism (PTE). Objective: The present study assessed the occurrence of PTE after the intravenous infusion of canine AdMSCs (cAdMSCs) into experimental animals. Methods: Five-week-old male BALB/c hairless mice were categorized into groups labeled A to G. In the control group (A), fluorescently stained 2×10⁶ cAdMSCs were diluted in 200 µL of suspension and injected into the tail vein as a single bolus. The remaining groups included the following: group B with 5×10⁶ cells, group C with 3×10⁶ cells, group D with 1×10⁶ cells, group E with 1×10⁶ cells injected twice with a one-day interval, group F with 2×10⁶ cells in 100 µL of suspension, and group G with 2×10⁶ cells in 300 µL of suspension. Results: Group D achieved a 100% survival rate, while none of the subjects in groups B and C survived (p = 0.002). Blood tests revealed a tendency for the D-dimer levels to increase as the cell dose increased (p = 0.006). The platelet count was higher in the low cell concentration groups and lower in the high cell concentration groups (p = 0.028). A histological examination revealed PTE in most deceased subjects (96.30%). Conclusions and Relevance: PTE was verified, and various variables were identified as potential contributing factors, including the cell dose, injection frequency, and suspension volume.

• Parasites, Hosts and Diseases
• /
• v.53 no.3
• /
• pp.259-263
• /
• 2015

The increasing prevalence of Toxoplasma gondii infection in the human population in the Republic of Korea (= Korea) is due to various reasons such as an increase in meat consumption. However, the importance of cats in transmitting T. gondii infection through oocysts to humans has seldom been assessed. A total of 300 fecal samples of stray cats captured around Seoul from June to August 2013 were examined for T. gondii B1 gene (indicating the presence of oocysts) using nested-PCR. Fourteen (4.7%) of 300 cats examined were positive for B1 gene. Female cats (7.5%) showed a higher prevalence than male cats (1.4%). Cats younger than 3 months (5.5%) showed a higher prevalence than cats (1.5%) older than 3 months. For laboratory passage of the positive samples, the fecal suspension (0.2 ml) of B1 gene positive cats was orally inoculated into experimental mice. Brain tissues of the mice were obtained after 40 days and examined for the presence of tissue cysts. Two isolates were successfully passaged (designated KNIH-1 and KNIH-2) and were molecularly analyzed using the SAG5D and SAG5E gene sequences. The SAG5D and SAG5E gene sequences showed high homologies with the ME49 strain (less virulent strain). The results indicated the importance of stray cats in transmitting T. gondii to humans in Korea, as revealed by detection of B1 gene in fecal samples. T. gondii isolates from cats were successfully passaged in the laboratory for the first time in Korea.