Analysis of S-locus and expression of S-alleles of self-compatible rapid-cycling Brassica oleracea 'TO1000DH3'.

Brassica oleracea is a strictly self-incompatible (SI) plant, but rapid-cycling B. oleracea 'TO1000DH3' is self-compatible (SC). Self-incompatibility in Brassicaceae is controlled by multiple alleles of the S-locus. Three S-locus genes, S-locus glycoprotein (SLG), S-locus receptor kinase (SRK) and S-locus protein 11 or S-locus cysteine-rich (SP11/SCR), have been reported to date, all of which are classified into class I and II. In this study, we investigated the molecular mechanism behind alterations of SI to SC in rapid-cycling B. olerace 'TO1000DH3'. Class I SRK were identified by genomic DNA PCR and PCR-RFLP analysis using SRK specific markers and found to be homozygous. Cloning and sequencing of class I SRK revealed a normal kinase domain without any S-domain/transmembrane domain. Moreover, S-locus sequencing analysis revealed only an SLG sequence, but no SP11/SCR. Expression analysis showed no SRK expression in the stigma, although other genes involved in the SI recognition reaction (SLG, MLPK, ARC1, THL) were found to have normal expression in the stigma. Taken together, the above results suggest that structural aberrations such as deletion of the SI recognition genes may be responsible for the breakdown of SI in rapid-cycling B. oleracea 'TO1000DH3'.

Evaluation of echocardiographic markers in dogs with patent ductus arteriosus after ductal closure

This study evaluated several known echocardiographic markers related to the assessment of severity in dogs with patent ductus arteriosus (PDA) after the closure of ductus arteriosus (DA). Forty-two dogs with patent ductus arteriosus were enrolled in this study. Evaluated echocardiographic markers were left atrial to aortic root ratio, left ventricular end-diastolic dimension to aortic root ratio, indexed left ventricular end-diastolic and end-systolic dimensions, end-diastolic and end systolic volume index, pulmonic flow to systemic flow (Qp/Qs) ratio, velocities of pulmonary regurgitant and systolic jets, pulmonary flow profiles and the presence of mitral regurgitation. Those markers were evaluated before, 1 day, and 30 days after the closure of DA. Statistically significant changes in some echocardiographic markers (i.e., Qp/Qs) were observed. Although several studies in human and dogs have evaluated the clinical outcome of PDA occlusion using several echocardiographic markers, this study has firstly evaluated all echocardiographic markers known to be useful for assessing the clinical outcome of PDA occlusion in human, and has demonstrated that those markers including the Qp/Qs and pulmonary flow profiles were useful in evaluating of clinical outcome of PDA in dogs and the reduction of LA and LV preload after ductal closure could dramatically reduce after successful ductal occlusion of PDA in dogs.

Volumetric modulated arc therapy for carotid sparing in the management of early glottic cancer

PURPOSE: Radiotherapy of the neck is known to cause carotid artery stenosis. We compared the carotid artery dose received between volumetric modulated arc therapy (VMAT) and conventional fixed-field intensity-modulated radiotherapy (IMRT) plans in patients with early glottic cancer. MATERIALS AND METHODS: Twenty-one early glottic cancer patients who previously underwent definitive radiotherapy were selected for this study. For each patient, double arc VMAT, 8-field IMRT, 3-dimensional conformal radiotherapy (3DCRT), and lateral parallel-opposed photon field radiotherapy (LPRT) plans were created. The 3DCRT plan was generated using lateral parallel-opposed photon fields plus an anterior photon field. VMAT and IMRT treatment plan optimization was performed under standardized conditions to obtain adequate target volume coverage and spare the carotid artery. Dose-volume specifications for the VMAT, IMRT, 3DCRT, and LPRT plans were calculated with radiotherapy planning system. Monitor units (MUs) and delivery time were measured to evaluate treatment efficiency. RESULTS: Target volume coverage and homogeneity results were comparable between VMAT and IMRT; however, VMAT was superior to IMRT for carotid artery dose sparing. The mean dose to the carotid arteries in double arc VMAT was reduced by 6.8% compared to fixed-field IMRT (p < 0.001). The MUs for VMAT and IMRT were not significantly different (p = 0.089). VMAT allowed an approximately two-fold reduction in treatment delivery time in comparison to IMRT (3 to 5 minutes vs. 5 to 10 minutes). CONCLUSION: VMAT resulted in a lower carotid artery dose compared to conventional fixed-field IMRT, and maintained good target coverage in patients with early glottic cancer.

A Successful Case of a High Anti A/B Antibody Titer ABO Incompatible Kidney Transplantation Patient Who Received a Kidney from a Hepatitis B Carrier / 대한이식학회지

Kidney transplantation (KTP) lowers the mortality and morbidity of patients with end-stage renal disease. Post-transplantation infection and antibody mediated rejection (AMR) are the most common complications. Hepatitis B surface antigen (HBsAg) positive carrier donors and high anti A/B antibody titer ABO incompatible KTP could lead to recipient hepatitis B virus (HBV) infection and AMR. Here, we report a case of successful KTP in a 41-year-old male with a high titer of ABO incompatible and HBsAg positive donor. He underwent seven rounds of plasmapheresis, low dose intravenous immunoglobulin and rituximab treatment to inhibit antibody production and remove antibodies from the serum, after which he was administered anti-viral agent for HBV prophylaxis. The recipient maintained successful allograft function for 6 months after transplantation; therefore, we report that desensitization and anti-viral treatment achieved successful outcome in a 1:512 anti A/B antibody titer ABO incompatible and hepatitis B carrier donor KTP.

Selective Mitochondrial Uptake of MKT-077 Can Suppress Medullary Thyroid Carcinoma Cell Survival In Vitro and In Vivo

BACKGROUND: Medullary thyroid carcinoma (MTC) is a neuroendocrine tumor mainly caused by mutations in the rearranged during transfection (RET) proto-oncogene. Not all patients with progressive MTC respond to current therapy inhibiting RET, demanding additional therapeutic strategies. We recently demonstrated that disrupting mitochondrial metabolism using a mitochondria-targeted agent or by depleting a mitochondrial chaperone effectively suppressed human MTC cells in culture and in mouse xenografts by inducing apoptosis and RET downregulation. These observations led us to hypothesize that mitochondria are potential therapeutic targets for MTC. This study further tests this hypothesis using1-ethyl-2-[[3-ethyl-5-(3-methylbenzothiazolin-2-yliden)]-4-oxothiazolidin-2-ylidenemethyl] pyridinium chloride (MKT-077), a water-soluble rhodocyanine dye analogue, which can selectively accumulate in mitochondria. METHODS: The effects of MKT-077 on cell proliferation, survival, expression of RET and tumor protein 53 (TP53), and mitochondrial activity were determined in the human MTC lines in culture and in mouse xenografts. RESULTS: MKT-077 induced cell cycle arrest in TT and MZ-CRC-1. Intriguingly, MKT-077 also induced RET downregulation and strong cell death responses in TT cells, but not in MZ-CRC-1 cells. This discrepancy was mainly due to the difference between the capacities of these cell lines to retain MKT-077 in mitochondria. The cytotoxicity of MKT-077 in TT cells was mainly attributed to oxidative stress while being independent of TP53. MKT-077 also effectively suppressed tumor growth of TT xenografts. CONCLUSION: MKT-077 can suppress cell survival of certain MTC subtypes by accumulating in mitochondria and interfering with mitochondrial activity although it can also suppress cell proliferation via other mechanisms. These results consistently support the hypothesis that mitochondrial targeting has therapeutic potential for MTC.

A Case of Acute Antibody-Mediated Rejection Developed after Pretreatment with Rituximab and Plasma Exchange in a Highly-Sensitized Recipient with a Deceased Donor Kidney / 대한이식학회지

Acute antibody-mediated rejection is the major cause of graft failure in the early stage of kidney transplantation. Preoperative treatment and early diagnosis of acute rejection is very important to prevent graft loss in sensitized patients. High panel reactive antibody (PRA) means a likelihood of acute rejection, and the recipient of high PRA needs adequate pretreatment for kidney transplantation. However, there is not sufficient time and chances for desensitization in deceased kidney transplants. We report a successful renal transplant outcome in a 47-year-old-woman with high PRA levels (Class I 97.5%, Class II 36.7%). The cross match was negative on the CDC (ELISA) and flowcytometric methods. Plasma exchange was performed on the recipient before transplantation (fresh frozen plasma replacement, 1.3 plasma volume) and immediately after plasma exchange she was given 200 mg of rituximab. She received basiliximab and methyl prednisolone induction therapy and was maintained on steroids, mycophenolate mofetil, and tacrolimus. Graft function was normal immediately after transplantation, but decreased urinary output and elevated serum creatinine was noted on POD 5. On POD 6, a graft biopsy revealed acute cellular rejection (Type IIa) and antibody-mediated rejection (Type II). On 9~13 days after transplantation, additional plasma exchange was performed every other day, and steroid pulse therapy was performed 3 times. After normalization of urinary output and serum creatinine, the patient was discharged and is being followed up on. In conclusion, immunologically careful preparation and pretransplant treatment may be needed on the negative cross match in cadaveric kidney recipients with high levels of PRA.

A Case of Nocardiosis with CMV (Cytomegalovirus) Infection after Third Renal Transplantation in China / 대한이식학회지

It has been well known that long-term immune suppression in renal transplant patients increases the possibility of complications. Infectious disease is one of the representative complications. We experienced a case of nocardiosis with cytomegalovirus infection after third renal transplantation in China. Nocardiosis is an important opportunistic infection in immunosuppressed patients, lymphoma, sarcoidosis, and organ transplant patients. CMV can cause severe hepatitis, pneumonitis, enteritis, endometritis, and encephalitis. It can depress bone marrow, and impair the immune system so as to increase other bacterial infection and trigger rejections. Third renal transplantation causes long-term immune suppression or over-immune suppression on transplant patients. Very few cases of third renal transplantation have been reported in Korea. We reduced the dose of immune- suppressants, and treated it successfully with ganciclovir and Trimethoprim/Sulfamethoxazole (Bactrim(R)).

Comparison of Susceptibility Test and mecA Detection for Determination of Methicillin Resistance in Staphylococcus epidermidis / 대한임상병리학회지

BACKGROUND: Staphylococcus epidermidis is a leading cause of nosocomial infections, and resistance to methicillin is common in clinical isolates. The distribution of oxacillin MIC for S. epidermidis is not clearly bimodal and it is suspected that the sensitivities for detection of oxacillin resistance by standard susceptibility assays with National Committee for Clinical Laboratory Standards (NCCLS) MIC interpretive criteria ( OR =4 g/mL) in S. epidermidis strains are lower than that in Staphylococcus aureus strains. To evaluate the relationship between MIC results and true methicillin resistance, we examined the oxacillin MICs and methicillin MICs by agar dilution and detection of mecA gene by PCR for 41 S. epidermidis strains. METHODS: A total of 41 S. epidermidis strains were examined antimicrobial susceptibility test by VITEK system with GPS-AA card, oxacillin MICs and methicillin MICs by agar dilution and detection of mecA gene by PCR. RESULTS: In antimicrobial susceptibility test by VITEK system with GPS-AA card, 24 strains (58.5%) showed oxacillin resistance. 13 strains (31.7%) required MICs of > OR =4 g/mL in oxacillin MIC test and 19 strains (46.3%) required MICs of > OR =16 g/mL in methicillin MIC test. But 27 strains (65.9%) were mecA positive. One of 15 strains that required oxacillin MICs of < OR =0.5 g/mL, all 3 strains that required oxacillin MICs of 1 g/mL and all 10 strains that required oxacillin MICs of 2 g/mL were mecA positive. CONCLUSIONS: It is suspected that NCCLS MIC interpretive criteria underestimate methicillin resistance among S. epidermidis strains and the PCR method is a reliable reference method.

Detection of M. tuberculosis by LCx M. tuberculosis Assay / 대한임상병리학회지

BACKGROUND: Mycobacterial culture is a confirmatory test to detect the Mycobacterium tuberculosis, but it requires considerable time and the diagnosis and treatment may be delayed. The recently developed LCR (ligase chain reaction) is a more rapid and more specific test for the detection of M. tuberculosis. In this study, we compared the LCR results with those of the culture and AFB smear. METHODS: Mycobacterial culture was performed on 3% Ogawa media for 8 weeks. For LCR, we used LCx Mycobacterium tuberculosis assay kit (Abbott Laboratories, North Chicago, Ill.). The specimens for LCR were resuspended to LCx respiratory specimen resuspension buffer, and then separated mycobacterial DNA by ultrasonicator (Abbott LCx Lysor). Then the samples were mixed in amplification vial containing DNA polymerase and DNA ligase and amplified. For the detection, we used LCx analyzer from Abbott laboratories. RESULTS: The sensitivity, specificity, and positive and negative predictive values of the LCx M. tuberculosis assay were 95, 100, 100, 60%, respectively; 90, 100, 100, 42.9%, for culture; and 62.5, 100, 100, 16.7%, for acid-fast staining, respectively. The agreements between culture and LCx, smear and LCx, and culture and AFB smear were 86%, 65% and 60%, respectively. CONCLUSIONS: LCx was confirmed as a more rapid and sensitive test than the culture test and AFB smear.

Expression of Ki-67/MIB-1 in Bone Marrow Biopsies from Patients with Myelodysplastic Syndromes and Aplastic Anemia / 대한임상병리학회지

BACKGROUND: Sometimes myelodysplastic syndrome (MDS) is especially difficult to distinguish from acquired aplastic anemia (AA) because of the clinical, cytologic, and histologic similarities of these two disorders. The proliferative activity of the hematopoietic cells is very different in various hematologic disorders and Ki-67 expression in the bone marrow cells is an useful cell proliferation marker. We tried to evaluate the significance of Ki-67/MIB-1 immunoreactivity in the discrimination of MDS and AA. METHODS: Bone marrow biopsy specimens from 56 individuals, 7 controls, 21 with MDS, 16 with AA and 12 with acute leukemia were obtained in Pusan Paik Hospital. Immunohistochemial staining for Ki-67 antigen was assessed by the MIB-1 monoclonal antibody using a microwave oven-based antigen retrieval technique. RESULTS: The mean values (+/-SD) of Ki-67 positive cells was as follows: control group, 16.8+/-3.6%; MDS, 25.3+/-10.1%; AA, 5.1+/-2.9%; acute leukemia, 30.5+/-10.4%. MDS cases showed statistically higher values of Ki-67 than did those of AA cases and control group (P<0.001) but no significance in Ki-67 frequencies was observed between the cases of MDS and acute leukemia. CONCLUSIONS: In the bone marrows of MDS cases the Ki-67 positive cells were frequently observed, suggesting high proliferative activity even in the nonleukemic state, while most of the bone marrows in AA showed very low proliferative activity. Thus immunohistochemical staining with Ki-67/MIB-1 would be useful in the discrimination of AA and MDS by the difference of Ki-67 positive cell percentage in the bone marrow.

Comparison of the Usefulness of Pulsed-Field Gel Electrophoresis and Ribotyping in Epidemiological Study of Methicillin-Resistant Staphylococcus aureus / 대한임상병리학회지

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most frequent agents of hospital infections. The aim of this study was to evaluate the polymorphism of MRSA strains from our hospital by pulsed-field gel electrophoresis (PFGE) and ribotyping, and to compare effectiveness of two methods for epidemiologic investigation. METHODS: A total of 40 MRSA isolates were studied. All strains were isolated from patients from October 1990 to May 1995: 13 isolates from NS ward, 9 from GS and OS ward, 11 from medical ward, and 7 from other medical centers. All strains were analyzed and classified by ribotyping and PFGE patterns. RESULTS: Eight different ribotypes (H1-H8) and ten ribotypes (E1-E10) were seen by HindIII and EcoRI digestion. The problem was that some isolates showed discordance between classifications by HindIII and EcoRI digestion and three isolates from other medical centers had same ribotypes with that of our hospital strains. PFGE analysis revealed 19 different types (A to S). The PFGE analysis showed ward specificity, 54% of isolates from NS ward and 54% of isolates from medical ward were PFGE types D and J respectively, and 33% of isolates from GS and OS ward was H type and 33% was G type. CONCLUSIONS: PFGE was a more effective epidemiological tool for the typing of MRSA strains but a combination with ribotyping could provide more detailed strain differentiation.

Comparison of serotypes, restriction enzyme analysis of plasmid DNA pattern and PFGE(pulsed-field gel electrophoresis) patterns of Yersinia pseudotuberculosis isolates in Korea / 대한임상병리학회지

BACKGROUND: Yersinia pseudotuberculosis, a member of genus Enterobactericeae, is a main etiologic organism of diarrhea in childhood. Because a mouse and a unchlorinated spring water are main reservoirs of Y. pseudotuberculosis, the strains from a contaminated spring water and mouse could be involved in human epidemic. The purpose of this study was to investigate a clonality between the strains from patients and those from an unchlorinated spring water and a mouse by restriction enzyme analysis of plasmid DNA and pulsed-field gel electrophoresis (PFGE). METHOD: We isolated 15 Y. pseudotuberculosis strains including 8 isolates from patients (S1-S8), 6 isolates from mountain water (W1-W6), 1 isolate from a mouse (M1) in northeast area of Seoul. Plasmid and chromosomal DNA of all strains were analyzed by REAP with Bam H1 restriction and by PFGE with Xba I restriction , respectively. RESULTS: Restriction enzyme analysis of plasmid DNA was classified into type B and type D. All 7 strains of serotype 15 were classified as type B and 8 strains of serotype 4b were classified as type D. PFGE were classified into 6 different types. Among them, strains of PFGE type I, II, III, IV belong to Y. pseudotuberculosis serotype 15 and Y. pseudotuberculosis 4b strains were classified into PFGE type V, VI. S1 and W1 were classified into PFGE type I . S8, W6 and M1 were classfied into PFGE type VI. CONCLUSIONS: PFGE revealed clonality among strains from patients, a water and a mouse. PFGE was more discriminative than REAP to characterize the Y. pseudotuberculosis outbreaks in Korea.