• The Korean Journal of Nuclear Medicine Technology
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• v.27 no.2
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• pp.111-127
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• 2023

Purpose: Gallium-68 (⁶⁸Ga) is increasingly used in nuclear medicine imaging for various conditions such as lymphoma and neuroendocrine tumors by labeling tracers like Prostate Specific Membrane Antigen (PSMA) and DOTA-TOC. However, compared to Fluorine-18 (¹⁸F) used in conventional nuclear medicine imaging, ⁶⁸Ga has lower spatial resolution and relatively higher Signal to Background Ratio (SBR). Therefore, this study aimed to investigate the optimized parameters and reconstruction methods for PET/CT imaging using the ⁶⁸Ga radiotracer through model-based image evaluation. Materials and Methods: Based on clinical images of ⁶⁸Ga-PSMA PET/CT, a NEMA/IEC 2008 PET phantom model was prepared with a Hot vs Background (H/B) ratio of 10:1. Images were acquired for 9 minutes in list mode using DMIDR (GE, Milwaukee WI, USA). Subsequently, reconstructions were performed for 1 to 8 minutes using OS-EM (Ordered Subset Expectation Maximization) + TOF (Time of Flight) + Sharp IR (VPFX-S), and BSREM (Block Sequential Regularized Expectation Maximization) + TOF + Sharp IR (QCFX-S-400), followed by comparative evaluation. Based on the previous experimental results, images were reconstructed for BSREM + TOF + Sharp IR / 2 minutes (QCFX-S-2min) with varying β-strength values from 100 to 700. The image quality was evaluated using AMIDE (freeware, Ver.1.0.1) and Advanced Workstation (GE, USA). Results: Images reconstructed with QCFX-S-400 showed relatively higher values for SNR (Signal to Noise Ratio), CNR (Contrast to Noise Ratio), count, RC (Recovery Coefficient), and SUV (Standardized Uptake Value) compared to VPFX-S. SNR, CNR, and SUV exhibited the highest values at 2 minutes/bed acquisition time. RC showed the highest values for a 10 mm sphere at 2 minutes/bed acquisition time. For small spheres of 10 mm and 13 mm, an inverse relationship between β-strength increase and count was observed. SNR and CNR peaked at β-strength 400 and then decreased, while SUV and RC exhibited a normal distribution based on sphere size for β-strength values of 400 and above. Conclusion: Based on the experiments, PET/CT imaging using the ⁶⁸Ga radiotracer yielded the most favorable quantitative and qualitative results with a 2 minutes/bed acquisition time and BSREM reconstruction, particularly when applying β-strength 400. The application of BSREM can enhance accurate quantification and image quality in ⁶⁸Ga PET/CT imaging, and an optimization process tailored to each institution's imaging objectives appears necessary.

• Journal of Veterinary Clinics
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• v.30 no.2
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• pp.115-118
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• 2013

An 8-year-old spayed female domestic shorthair cat was presented with a chief complaint of chronic nasal discharge and dyspnea. Physical examination revealed pyohemorrhagic nasal discharge, inspiratory dyspnea and stertor, and an enlarged right mandibular lymph node. Abnormalities of blood works and serum chemistry included mildly increased hematocrit, and globulin concentration. Serologic tests for FeLV and FIV, and a panel of polymerase chain reaction tests for Chlamydophila felis, Feline Calicivirus, Herpesvirus, Bordetella, Mycoplasma felis, and H1N1 influenza was all negative. Only radiographic finding showed increasing soft tissue density in the right nasal cavity and computed tomography disclosed soft tissue/fluid opacification in the right nasal cavity, paranasal sinus, and pharyinx along with slight deviation to the right of the osseous nasal septum. Focal lysis of ventral nasal septum was also suspected in CT scan. Cytological evaluation of fine needle aspirate smears of the enlarged mandibular lymph nodes revealed numerous fungal yeasts having variably thick capsule both extracellularly and intracellularly with low numbers of macrophages. Some yeasts showed narrow based budding, which was a consistent finding with Cryptococcus organisms. Serum protein electrophoresis was a polyclonal consistent with chronic infection and serum was submitted for a fungal serology panel test. In serologic tests Cryptococcus antigen titer was 1 : 32,768. In vitro culture was unsuccessful. Treatment was initiated with administration of fluconazole, clindamycin, and tocopherol. Clinical signs resolved within 3 days after the initial treatment. The cat was discharged and scheduled for periodic evaluation and continued therapy, but was lost to follow-up thereafter.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.9 no.1
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• pp.17-21
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• 2023

In this study, we evaluated the targeting of prostate cancer (PCa) using [¹⁸F]Florastamin in non-clinical study, for the purpose of therapeutic monitoring of [¹⁷⁷Lu]Ludotadipep, a therapeutic radiopharmaceutical for PCa, [¹⁸F]Florastamin/[¹⁷⁷Lu]Ludotadipep was co-administered to a single-individual prostate tumor bearing mouse model, mimicking clinical condition. Considering the difference in half-life of the two isotopes (¹⁸F or ¹⁷⁷Lu), image scan of whole-body autoradiography was performed at 24 or 48 h after preparation of frozen section, respectively. Then, it was confirmed whether they showed the same targeting efficiency for the area of tumor. A tumor xenograft model was prepared using PSMA-overexpressing PC3-PIP prostate cancer cells. [¹⁸F]Florastamin [111 MBq (3 mCi) in 100 µL]/¹⁷⁷Lu]Ludotadipep [3.7 MBq (100 µCi) in 100 µL] was co-administered through the tail vein, and 2 hours after administration, the mice were frozen, and after freezing for 24 hours, whole-body cryosection was performed at 24 h after freezing. Image scanning using cryosection was performed after 24 or 48 hours after freezing, respectively. In the scan image after 24 hours, tumor uptake of [¹⁸F] Florastamin/[¹⁷⁷Lu]Ludotadipep were simultaneously observed specific uptake in the tumor. In the scan image after 48 hours in the same section, signal of ¹⁸F was lost by decay of radioisotope, and specific uptake image for [¹⁷⁷Lu]Ludotadipep was observed in the tumor. Uptake of [¹⁷⁷Lu]Ludotadipep was specific to the same tumor region where [¹⁸F]Florastamin/[¹⁷⁷Lu]Ludotadipep was uptake. These results suggested that [¹⁸F]Florastamin showed the same tumor uptake efficiency to PCa as [¹⁷⁷Lu]Ludotadipep, and effective therapeutic monitoring is expected to be enable using [¹⁸F]Florastamin during [¹⁷⁷Lu]Ludotadipep therapy for PCa.

• Journal of Veterinary Clinics
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• v.26 no.2
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• pp.138-143
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• 2009

Ischemia/reperfusion injury(I/RI) is the major cause of acute renal failure and delayed graft function(DGF) unavoidable in renal transplantation. Enormous studies on ischemia damage playing a role in activating graft rejection factors, such as T cells or macrophages, are being reported. Present study was performed to determine whether ischemia time would play an important role in activating rejection-related factors or not in rat models of I/RI. Male Sprague-Dawley rats were submitted to 30, 45, and 60 minutes of warm renal ischemia with nephrectomy or control animals underwent sham operation(unilateral nephrectomy). Renal function and survival rates were evaluated on day 0, 1, 2, 3, 5 and 7. Immunofluorescence staining of dendritic cells(DCs), natural killer(NK) cells, macrophages, B cells, CD4+ and CD8+ T cells were measured on day 1 and 7 after renal I/RI. Survival rates dropped below 50% after day 3 in 45 minutes ischemia. Histologic analysis of ischemic kidneys revealed a significant loss of tubular architecture and infiltration of inflammatory cells. DCs, NK cells, macrophages, CD4+ and CD8+ T cells were infiltrated from a day after I/RI depending on ischemia time. Antigen presenting cells(DCs, NK cells or macrophages) and even T cells were infiltrated 24 hours post-I/RI, which is at the time of acute tubular necrosis. During the regeneration phase, not only these cells increased but B cells also appeared in more than 45 minutes ischemia. The numbers of the innate and the adaptive immune cells increased depending on ischemia as well as reperfusion time. These changes of infiltrating cells resulting from each I/RI model show that ischemic time plays a role in activating rejection related immune factors and have consequences on progression of renal disease in transplanted and native kidneys.

• Korean Journal of Veterinary Research
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• v.25 no.1
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• pp.7-17
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• 1985

Many investigators have been pursuing various attempts so far to produce hepatitis B surface antigen(HBsAg) vaccines using the techniques such as isolation from plasma of chronic HBsAg carrier, recombinant DNA technique or preparation of synthetic peptides specific for immunogenic determinants. Hepatitis B virus can not grow on any cell lines by the tissue culture technique at the present time. The plasma of chronic HBsAg carrier is expensive and its source is limited. The HBsAg from the recombinant DNA technique gave still very low yield. Another approach, therefore, has been initiated to develop a synthetic hepatitis B virus vaccine. The possible use of several distinct synthetic vaccines in prophylaxis can be facilitated by availability of full synthetic immunogens. Peptides synthesized for potential application as antiviral vaccines have been mostly tested in the form of conjugates with carrier proteins, although the free synthetic peptide can be immunogenic. To understand basic knowledges on the antigenicity and immunogenicity of a synthetic peptide specific for major immunogenic determinant of HBsAg, a nonapeptide, $H_2N^{139}Cys-Thr-Lys-Pro-Thr-Asp-Gly-^{146}Asn-Aba$ COOH, which corresponds to HBsAg amino acid residues 139 to 147, was synthesized by the Merrifield's solid-phase method with a slight modification. The antigenicity and immunogenicity of this specific synthetic peptide were examined comparing with purified plasma-derived natural HBsAg. The results obtained are as follows; 1. The peptide synthesized showed the identical amino acid composition to the theoretical value. The degree of purification and molecular weight were acertained by methods of high performance liquid chromatography and mass spectrometry. 2. Using m-maleimidobenzoyl-N-hydroxysuccinimide ester as a conjugating agent, the synthetic peptide was conjugated to rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin. Their conjugation yields were 8.3, 9.5, 15.8, 13.5, and 11.2%, respectively. 3. The natural HBsAg was purified from plasma of chronic HBsAg carrier. By the electron microscopic observation of the purified natural HBsAg preparation, no Dane particles were observed and the preparation showed negative DNA polymerase activity. 4. Antigenicity of the synthetic peptide and the plasma-derived natural HBsAg was determined by competition radioimmunoassay using $^{125}I$-natural HBsAg. Their 50% inhibitions appeared as $90{\mu}g/ml$ and $0.12{\mu}g/ml$ for the synthetic peptide and the natural HBsAg, respectively. This indicates that the former was about 750-fold less antigenic than the latter. 5. Immunogenicity of the synthetic peptide was determined by administering the peptide-carrier conjugates into rabbits with and without Freund's complete adjuvant. Regardless the carrier proteins and adjuvant, positive immune responses to the synthetic peptide were observed. The higher antibody titers, however, were shown in the groups administered with Freund's complete adjuvant. 6. Immunizing dose 50% in mice of the various peptide-carrier conjugates was 5.47, 6.00, 65.16, 31.25 and $13.03{\mu}g/dose$ for rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin, respectively, while the natural HBsAg showed $0.65{\mu}g/dose$. 7. It was postulated that homologous proteins prefer to heterologous ones as the carriers.

• Korean Journal of Animal Reproduction
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• v.16 no.4
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• pp.289-299
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• 1993

The polypeptide patterns of cellular and follicular components were analysed by SDS-PAGE and two dimensional(2-D)electrophoresis combined with isoelectric focusing (IEF) to establish protein profiles in each of the components in porcine follicles. Oocyte-cumulus complexes were cultured in M16+FCS+Gn at 39 in an atmosphere of 5% CO$_2$, in air for 35 h. At the end of the culture, the zona-free oocyte, ZP alone and cumulus cells were prepared and analysed either on 10% SDS-PAGE for the protein profile at the first dimensional gel or 2-D protein pattern. The amounts of each samples were determined for the visualization with Coomasie brilliant blue (CBB) or silver staining, thus giving useful information for the identification of specific proteins in the components or appropriate amount of samples for proper visualization. Oocyte showed 25 and 114 kd major protein band. Other minor components were additionally visualized with CBB on the same gel after silver staining procedure. Cumulus cells also showed specific proteins which is not present in the oocytes. The number of cumulus cell was proper to give major bands with CBB and additional minor bands with silver staining. To establish the degree of contamination from the remnant of the corona radiata to the ZP, zonae were differently prepared or analysed by SDS-PAGE.The preparation of the ZP in this study did not showed any contamination judged by the protein profile of the components. Also follicular fluid showed its specific protein profile without any significant differences among the different sizes of follicles. The established protein profile of each follicular component should be helpful for the identification and elimination of contaminated components, i. e., antigen preparation or immunological studies. The results also suggest that the preparation of each components in the study was appropriate and can be used for a further sensitive biochemical analysis in mammalian oocytes and early embryos.

• Parasites, Hosts and Diseases
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• v.58 no.3
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• pp.237-247
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• 2020

Dendritic cell is one of the first innate immune cell to encounter T. gondii after the parasite crosses the host intestinal epithelium. T. gondii requires intact DC as a carrier to infiltrate into host central nervous system (CNS) without being detected or eliminated by host defense system. The mechanism by which T. gondii avoids innate immune defense of host cell, especially in the dendritic cell is unknown. Therefore, we examined the role of host PI3K/AKT signaling pathway activation by T. gondii in dendritic cell. T. gondii infection or T. gondii excretory/secretory antigen (TgESA) treatment to the murine dendritic cell line DC2.4 induced AKT phosphorylation, and treatment of PI3K inhibitors effectively suppressed the T. gondii proliferation but had no effect on infection rate or invasion rate. Furthermore, it is found that T. gondii or TgESA can reduce H₂O₂-induced intracellular reactive oxygen species (ROS) as well as host endogenous ROS via PI3K/AKT pathway activation. While searching for the main source of the ROS, we found that NADPH oxidase 4 (NOX4) expression was controlled by T. gondii infection or TgESA treatment, which is in correlation with previous observation of the ROS reduction by identical treatments. These findings suggest that the manipulation of the host PI3K/AKT signaling pathway and NOX4 expression is an essential mechanism for the down-regulation of ROS, and therefore, for the survival and the proliferation of T. gondii.

• Korean Journal of Veterinary Service
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• v.18 no.2
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• pp.113-123
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• 1995

The present study was conducted to investigate the prevalent characteristics of Fowl Typhoid and antibiotic susceptibility of Salmonella gallinarum isolated from 56 infective or dead chickens of 20 egg laying farms in Kyung Buk province during the period from August to December 1994. 1. Among 416, 000 chickens of 92 flocks in 20 egg laying farms, 17, 360 chickens of 31 flocks were died of Fowl Typhoid. 2. Salmonella gallinarum was isolated from 56 chickens in liver and spleen, and then blood of infective chickens was positive to Pullorum antigen. 3, In the survey of gross lesion of 56 chickens, 43 chickens(76.8%) were swelled at liver, 39(69.6%) were swelled at spleen, 12(21.4%) were changed with bronze, 3(5.4% ) were hemorrhagic in peritoneal cavity. 4. In transmission pattern, 4 farms were outbreaked the entrance of chicken house at first, but the others were outbreaked at various place. They were transmitted at right and left directions in flock. 5. 2 farms confirmed at the early stage of infection were eradicated by removing infective chickens and administrating antibiotics, but 18 farms at chronic stage were not. 6. The biochemical properties of 112 Salmonella gallinarum from chickens were generally identical to those of the referance, but H$_2$S was not productive, cellobiose was fermentive. 7 Minimum inhibitory concentration(MIC) of 20 isolates was performed by using 21 antibiotics, MICs of Amikacin(Ak), Gentamicin(Gm), Kanamycin(Km), and Tetracycline (Tc) were below 1.6 ug/ml, Ampicillin(Am), Furazolidone(Fu) and Neomycin(Nm) were below 3.1 ug/ml, Cephalothin(Ce), Cefazoline(Cf) and Chloramphenicol(Cm) were below 6.3 ug/ml, Nalidixic acid(Na), Polymyxin(Po) and Rifampicin(Rf) were below 12.5 ug/ml, Penicillin (Pm) was below 25 ug/ml, Colistin(Co) and Streptomycin(Sm) were below 50 ug/ml, Sulfamerazine(Sr) and Sulfamethazine (St) were below 200 ug/ml, Lincomycin(Lm) and Spiramycin(Sp) were below 400 ug/ml, Bacitracin(Ba) was below 800 ug/ml. 8. Among the 20 isolates, all(100%) of those were sensitive to Ak, Am, Ce, Cf, Cm, Fu, Gm, Km, Na, Nm, Po, Rf, Sr, St and Tc, but 6 isolates(30%) were resistent to Co, 20(100% ) to Ba, Lm, Pm, Sm, and Sp. The drug resistance patterns were simple which 6 strains were BaCoLmPmSmSp type, and 14 were BaLmPmSmSp type.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.77-81
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• 2007

Diagnostic performance of polymerase chain reaction (PCR) for detecting Dirofilaria immitis in dogs was evaluated when no gold standard test was employed. An enzyme-linked immunosorbent assay test kit (SnapTM, IDEXX, USA) with unknown parameters was also employed. The sensitivity and specificity of the PCR from two-population model were estimated by using both maximum likelihood using expectation-maximization (EM) algorithm and Bayesian method, assuming conditional independence between the two tests. A total of 266 samples, 133 samples in each trial, were randomly retrieved from the heartworm database records during the year 2002-2004 in a university animal hospital. These data originated from the test results of military dogs which were brought for routine medical check-up or testing for heartworm infection. When combined 2 trials, sensitivity and specificity of the PCR was 96.4-96.7% and 97.6-98.8% in EM and 94.4-94.8% and 97.1-98% in Bayesian. There were no statistical differences between estimates. This finding indicates that the PCR assay could be useful screening tool for detecting heartworm antigen in dogs. This study was provided further evidences that Bayesian approach is an alternative approach to draw better inference about the performance of a new diagnostic test in case when either gold test is not available.

• Tuberculosis and Respiratory Diseases
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• v.45 no.5
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• pp.1031-1038
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• 1998

Background: Most of malignant pleural effusions are serous but 8-33% of them are bloody. We wanted to evaluate the relationships between gross appearance and pleural CEA level or results of histocytology in malignancy associated pleural effusions. We also tried to reevaluate the meaning of CEA measurement in histocytologically proved or unproved malignancy associated pleural effusions. Methods: We studied 98 cases of malignancy associated pleural effusions, 50 cases of histocytologically proven malignant effusions and 48 cases of histocytologically unproven paramalignant effusions. We had observed gross appearance and conventional laboratory values and CEA levels for pleural effusions. Results: 44.9% of malignancy associated effusions were bloody(63.6% of bloody effusions were histocytologically proven malignant effusion). 65.0% of malignancy associated pleural effusions which have RBCs numbers over $100,000/mm^3$ were cytologically proven malignant effusions. 72.7% of cytologically proven malignant effusions had increased pleural fluid CEA level over 10 ng/ml. 58.2% of cases with pleural CEA over 10 ng/ml had positive results in pleural bistocytology. There was no definable relationships between pleural fluid CEA elevation and RBCs numbers and results of pleural fluid cytology. Conclusion: About half of the cases with malignancy associated pleural effusions were bloody. Histocytologically proven malignant effusions were more common in bloody effusion than non-bloody effusion(63.6% Vs 38.9%). But increased red blood cell numbers was not associated with positivity of pleural histocytology. Pleural fluid CEA elevation(over 10 ng/ml) was not correlated with positive pleural histocytology. But pleural fluid CEA elevation was rare in nonmalignant pleural effusions, and than pleural CEA measurement in uncertain pleural effusions maybe helpful to distinguishes its origin.