Title Page
Contents
ABSTRACT 10
Chapter Ⅰ. In Vitro Evaluation of Anti-staphylococcal Activity of L. animalis and Its Supernatant against Multidrug-resistant S. pseudintermedius 14
1.1. Introduction 14
1.2. Materials and Methods 16
1.2.1. Bacterial strains and culture 16
1.2.2. Selecting a candidate L. animalis strain for in vitro evaluation 17
1.2.3. Selecting a candidate S. pseudintermedius strain as multidrug-resistant indicator for in vitro evaluation 18
1.2.4. Preparation of crude cell-free supernatant 19
1.2.5. Evaluation of anti-staphylococcal activity of selected L. animalis strain 20
1.2.6. Cytotoxicity assay of crude cell-free supernatant 21
1.2.7. Statistical analysis 22
1.3. Results 23
1.3.1. Selected L. animalis strain 23
1.3.2. Selected S. pseudintermedius as multidrug-resistant indicator bacteria 25
1.3.3. Anti-staphylococcal activity of crude cell-free supernatant 27
1.3.4. Cytotoxicity assay of crude cell-free supernatant 30
1.4. Discussion 32
Chapter Ⅱ. In Vivo Evaluation of Anti-staphylococcal Activity of Supernatant of L. animalis against Multidrug-resistant S. pseudintermedius with a Novel Acute Infectious Osteomyelitis Rat model 37
2.1. Introduction 37
2.2. Materials and Methods 39
2.2.1. Establishment of novel acute osteomyelitis rat model using S. pseudintermedius 39
2.2.2. Macroscopic evaluation 44
2.2.3. Radiographic evaluation 44
2.2.4. Histopathologic evaluation 45
2.2.5. Microbiologic evaluation 46
2.2.6. Statistical analysis 47
2.3. Results 48
2.3.1. Macroscopic evaluation 48
2.3.2. Radiographic evaluation 51
2.3.3. Histopathologic evaluation 54
2.3.4. Microbiologic evaluation 58
2.4. Discussion 61
Conclusion 67
References 68
국문초록 79
Table 1-1. Antibiotic susceptibility profile of staphylococci candidates. 26
Table 1-2. Inhibitory zone diameter observed against S. pseudintermedius KUVM1701GC. 29
Table 2-1. Experimental group design for in vivo test with a novel rat model. 41
Figure 1-1. Mean diameter of inhibitory zone of Ligilactobacillus spp. against Staphylococcus spp. 24
Figure 1-2. Agar spot assay with L. animalis SWLA-1, concentrated cell-free supernatant, and antibiotic disks against S. pseudintermedius KUVM1701GC. 28
Figure 1-3. CCK-8 assay results of C2C12 and UMR cells at 72 hours after treatment with concentrated L. animalis SWLA-1-derived cell-free supernatant... 31
Figure 2-1. Surgical procedure. 42
Figure 2-2. The mean differences between macroscopic scores of each experimental group. 49
Figure 2-3. Observed gross lesion. 50
Figure 2-4. The mean differences between radiographic scores of each experimental group. 52
Figure 2-5. Radiographic images from each group. 53
Figure 2-6. The mean differences between histopathologic scores of each experimental group. 55
Figure 2-7. Observed histopathologic lesions from group treated with PBS after staphylococcal injection stained with hematoxylin and eosin. 56
Figure 2-8. Histopathologic comparison between groups 57
Figure 2-9. The mean differences in re-isolated indicator bacterial colony counts (log 10 CFU/mL) from femoral bone marrow contents and screws used in animals between the experimental groups. 60