351
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Hong T, Ndamukong J, Millett W, Kish A, Win KK, Choi YJ. Direct application of Etest to gram-positive cocci from blood cultures: quick and reliable minimum inhibitory concentration data. Diagn Microbiol Infect Dis 1996; 25:21-5. [PMID: 8831041 DOI: 10.1016/0732-8893(96)00062-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The Etest was applied directly to 100 Gram-positive bacterial strains from blood cultures to measure their minimum inhibitory concentration (MIC). Results showed 100% concordance of MIC data between a direct Etest method and the standard Etest method for Streptococcus pneumoniae, beta-hemolytic streptococci, and viridans group streptococci. In addition, direct Etest for Staphylococcus aureus, coagulase negative staphylococci, Enterococcus faecium, and Enterococcus faecalis showed 83 to 100% correlation with standard Etests. These data indicate that the Etest is useful to obtain MIC data on Gram-positive cocci (especially streptococci) directly from positive blood cultures. The advantages of a direct Etest are two fold: MIC results can be obtained 24 hours earlier than standard methods and a more representative population of the bacterial isolate is tested.
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352
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Choi YJ, Hu Y, Mahmood A. Clinical significance of a polymerase chain reaction assay for the detection of Mycobacterium tuberculosis. Am J Clin Pathol 1996; 105:200-4. [PMID: 8607445 DOI: 10.1093/ajcp/105.2.200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Various investigators have reported rapid detection of Mycobacterium tuberculosis (MTB) in clinical samples by polymerase chain reaction (PCR). To improve the specificity and efficiency of PCR, the authors adopted a variety of conditions, then analyzed sputum specimens from 217 patients clinically suspected of having MTB. Sputum samples were sonicated to obtain MTB DNA. The DNA was subjected to PCR using primer sets from the region of 650-900 in MTB. The PCR product was detected by direct gel electrophoresis and Southern blot hybridization using digoxigenin-labeled MTB-specific probe. The results of smears, cultures, and PCR were concordant in 93% (202) of the 217 specimens and discordant in 7% (15). Fifteen of the discordant specimens, all from patients who had received antituberculosis medications for days to months, were PCR positive. Of these, 11 were culture negative and 3 were smear negative. Only one specimen was false negative on PCR. Our results indicate that PCR is the method of choice when clinical suspicion is high, but smears or cultures are negative. When smears are positive, PCR permits rapid distinction between MTB and other mycobacterial infections. Because PCR can detect nonviable MTB DNA, positive PCR should be interpreted in conjunction with clinical information.
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353
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Choi YJ, Kim CJ, Ji GE. A partially purified beta-glucosidase from Bifidobacterium adolescentis converts cycasin to a mutagenic compound. Lett Appl Microbiol 1996; 22:145-8. [PMID: 8936375 DOI: 10.1111/j.1472-765x.1996.tb01129.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
beta-Glucosidase was extracted from sonicated Bifidobacterium adolescentis Int-57 and partially purified by Sepharose CL-6B gel-filtration and DEAE-cellulose ion-exchange chromatography. The partially purified enzyme was confirmed to convert cycasin to a mutagen in the Ames and SOS chromotests. beta-Glucosidase negative strains were unable to activate cycasin mutagenically.
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354
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Yang CW, Lee SH, Choi YJ, Kim YS, Kim SY, Chang YS, Bang BK. Chronic granulomatous interstitial nephritis: unusual complication of acute pyelonephritis. Nephron Clin Pract 1996; 72:305-7. [PMID: 8684545 DOI: 10.1159/000188860] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
We describe an unusual complication of acute pyelonephritis in a 45-year-old diabetic female. She was admitted to our hospital due to fever and flank pain which had developed 10 days earlier. Urinalysis showed many WBC and urine culture revealed Escherichia coli. After adequate antibiotic treatment, clinical symptoms abated but renal failure and leukocyturia persisted. Abdominal CT showed bilateral focal bacterial nephritis and renal biopsy disclosed chronic granulomatous interstitial nephritis. On the 80th hospital day she was discharged with a serum creatinine of 299 mumol/l. In the outpatient clinic, renal dysfunction and leukocyturia persisted up to 1 year. In conclusion, this case raises the possibility of a chronic interstitial process of acute pyelonephritis.
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355
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Cho CS, Min JK, Park SH, Yang HI, Lee SH, Choi YJ, Kim BS, Kim HY. Protein losing enteropathy associated with Henoch-Schönlein purpura in a patient with rheumatoid arthritis. Scand J Rheumatol 1996; 25:334-6. [PMID: 8921929 DOI: 10.3109/03009749609104068] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Protein losing enteropathy is rarely associated with Henoch-Schönlein purpura. Moreover, the disease association of Henoch-Schönlein purpura and rheumatoid arthritis is also rare. We report a case of a 46 year old patient with rheumatoid arthritis presenting with Henoch-Schönlein purpura associated with protein losing enteropathy.
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356
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Feres-Filho EJ, Choi YJ, Han X, Takala TE, Trackman PC. Pre- and post-translational regulation of lysyl oxidase by transforming growth factor-beta 1 in osteoblastic MC3T3-E1 cells. J Biol Chem 1995; 270:30797-803. [PMID: 8530522 DOI: 10.1074/jbc.270.51.30797] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The final enzymatic step required for collagen cross-linking is the extracellular oxidative deamination of peptidyl-lysine and -hydroxylysine residues by lysyl oxidase. A cross-linked collagenous extracellular matrix is required for bone formation. The goals of this study were to compare the transforming growth factor (TGF)-beta 1 regulation of lysyl oxidase enzyme activity and steady state mRNA levels to changes in COL1A1 mRNA levels in MC3T3-E1 osteoblastic cells. TGF-beta 1 increased steady state lysyl oxidase and COL1A1 mRNA levels in a dose- and time-dependent manner. The increase in lysyl oxidase mRNA levels was transient, peaking at 12 h and 8.8 times controls in cells treated with 400 pM TGF-beta 1. COL1A1 steady state mRNA levels increased maximally to 3.5-fold of controls. Development of increased lysyl oxidase enzyme activity was delayed and was of slightly lower magnitude than the increase in its mRNA levels. This suggested limiting post-translational processing of lysyl oxidase proenzyme. Pulse-labeling/immunoprecipitation studies demonstrated slow proenzyme secretion and proteolytic processing. Development and application of an independent assay for lysyl oxidase proenzyme proteolytic processing activity verified its proportionately lower stimulation by 400 pM TGF-beta 1. Thus, lysyl oxidase regulation by TGF-beta 1 in osteoblastic cell cultures occurs at both pre- and post-translational levels. This regulation is consistent with increased production of a collagenous extracellular matrix.
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357
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Lee MK, Choi YJ, Sung SH, Shin DI, Kim JW, Kim YC. Antihepatotoxic activity of icariin, a major constituent of Epimedium koreanum. PLANTA MEDICA 1995; 61:523-526. [PMID: 8824946 DOI: 10.1055/s-2006-959362] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In an attempt to identify compounds with antihepatotoxic activity, carbon tetrachloride-induced cytotoxicity in primary cultured rat hepatocytes has been adopted as a screening system. Using this screening system, an antihepatotoxic compound from the aerial parts of Epimedium koreanum has been isolated. This compound, icariin, is a flavonol glycoside. Its antihepatotoxic activity was first evaluated by measuring the release of glutamic pyruvic transaminase and sorbitol dehydrogenase from CCl4-intoxicated rat hepatocytes into the culture medium. Icariin significantly reduced the level of glutamic pyruvic transaminase and sorbitol dehydrogenase released resulting in a 76% protection from toxicity at concentration ranges from 1 microM to 20 microM. The antihepatotoxic activity of icariin was also estimated by the determination of total cytochrome P-450 content and glutathione-S-transferase activity in the CCl4-intoxicated hepatocytes.
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358
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Son JY, Jeon HW, Choi YJ, Kostrov NA. Optimization of a three-dimensional object composite Fourier hologram. OPTICS LETTERS 1995; 20:776-778. [PMID: 19859326 DOI: 10.1364/ol.20.000776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
It was found that the optimum subhologram dimension of the composite Fourier-transform hologram for minimizing image blur depends on object depth and information reduction ratio. Optimization of the subhologram dimension permits us to calculate the parameters of the composite Fourier-transform hologram for its applications to hologram transmission systems and to electroholographic three-dimensional displays.
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359
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Trackman PC, Feres-Filho EJ, Choi YJ. The 3'-untranslated region of rat lysyl oxidase cDNA. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1260:355-60. [PMID: 7873615 DOI: 10.1016/0167-4781(94)00239-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The cloning of the 3'-untranslated region of rat lysyl oxidase cDNA was completed. cDNA clones were generated by reverse transcriptase PCR from neonatal rat aorta smooth muscle cell RNA, and sequenced. Several polyadenylated clones were obtained, providing 2.1 kb of new sequence. Clones were polyadenylated at three different positions. The cDNA clones were verified by PCR-cloning and sequencing of genomic DNA, and by Northern blotting studies. Evidence is presented that the polyadenylation patterns of rat lysyl oxidase mRNAs are similar, but not identical to mouse or human transcripts. Interestingly, the nonconsensus polyadenylations in rat did not occur at the same positions as was found in mouse lysyl oxidase cDNAs. Multiple transcription initiation sites were found by primer extension mapping. Thus, the complex pattern of rat lysyl oxidase mRNAs on Northern blots is principally due to differential use of polyadenylation signals, and to the occurrence of multiple transcription initiation sites. All clones lacked a previously reported 258 bp segment nearly identical to a conserved segment of the 3'-untranslated region of elastin cDNA. We conclude that the elastin-like sequence previously reported in rat lysyl oxidase cDNA is not a species-specific sequence, and most probably resulted from spurious ligation reactions during construction of the cDNA library.
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360
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Kim YS, Lee TH, Choi YJ. Effect of intermittent and stepwise administration of a beta-adrenergic agonist, L644,969, on rat growth performance and skeletal muscles. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART C, PHARMACOLOGY, TOXICOLOGY & ENDOCRINOLOGY 1995; 110:127-32. [PMID: 7599963 DOI: 10.1016/0742-8413(95)00002-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The effects of intermittent and stepwise administration of a beta-adrenergic agonist, L644,969 on rat growth performance and skeletal muscle growth were investigated in two studies. In experiment 1, 34 juvenile male rats were randomly assigned to two treatment groups: (1) control, 0 ppm L644,969 for 21 days; (2) BL10, 10 ppm of L644,969 for 7 days, then 0 ppm L644,969 for another 7 days, plus 10 ppm of L644,969 for the final 7 days. L644,969 increased (P < 0.05) weight gain during the 7 day initial administration period. When L644,969 was withdrawn, no difference in weight gain was observed between the two groups. Re-administration of L644,969 after the withdrawal period increased (P < 0.01) weight gain up to 3 days of re-administration, but no effect was observed thereafter. In experiment 2, 18 juvenile female rats were divided into three groups: (1) control, 0 ppm L644,969 for 22 days; (2) BL10, 10 ppm L644,969 for 22 days; (3) BL10-60, 10 ppm L644,969 for 11 days, then 60 ppm L644,969 for another 11 days. Feeding 10 ppm L644,969 increased (P < 0.05) the rate of weight gain up to 11 days, but not thereafter. Raising the dose of L644,969 from 10 to 60 ppm increased body weight gain during the initial 8 day period, but no effect was observed thereafter. Weights of skeletal muscles and heart were significantly increased by 10 ppm L644,969. Raising the dose to 60 ppm increased the mean skeletal muscle weights without statistical significance. Muscular concentration of cAMP was significantly decreased by the long-term administration of L644,969.(ABSTRACT TRUNCATED AT 250 WORDS)
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361
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Kang MS, Choi YJ, Kim MC, Lim CO, Hwang I, Cho MJ. Isolation and characterization of two beta-tubulin cDNA clones from rice. PLANT MOLECULAR BIOLOGY 1994; 26:1975-1979. [PMID: 7858231 DOI: 10.1007/bf00019507] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Two cDNA clones encoding two different beta-tubulins, RTUB-1 and RTUB-2, were isolated from a rice cDNA library and their nucleotide sequences were analyzed. The deduced amino acid sequences showed amino acid sequence identity between 92% and 97% with other plant beta-tubulins. Southern blot analysis using gene-specific and coding-region probes suggested that beta-tubulins in rice are encoded by multigene families. The two cDNA clones represent two subfamilies of rice tubulins, RTUB-1 and RTUB-2, consisting of 3 to 4 genes and a single gene, respectively. The transcript levels of RTUB-1 and RTUB-2 genes were higher in actively elongating tissues such as etiolated shoot tissues and light-grown root tissues of four-day old seedlings.
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362
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Yoo JH, Choi JY, Kim YR, Choi YJ, Shim SI, Kim HK, Yang CW, Kim YS, Hahn CW, Shin WS. Five cases of cytomegalovirus infection detected by in situ hybridization and antigenemia assay. J Korean Med Sci 1994; 9:507-12. [PMID: 7786449 PMCID: PMC3054226 DOI: 10.3346/jkms.1994.9.6.507] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We report five cases of cytomegalovirus infection in immunocompromised patients which were detected by either cytomegalovirus antigenemia assay or in situ hybridization. Four cases had leukemia and the other had chronic renal failure. All the three BMT recipients suffered from GvHD. Interestingly, there was an unique case of CMV disease without a history of BMT, which reminded us that CMV could attack immunocompromised patients who had not undergone transplantation, too. Four out of five cases died. We think that cytomegalovirus infection or disease should not be regarded as a minor problem in post-transplantation infection in Korea.
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MESH Headings
- Adolescent
- Adult
- Antigens, Viral/blood
- Bone Marrow Transplantation
- Cytomegalovirus/immunology
- Cytomegalovirus Infections/complications
- Cytomegalovirus Infections/diagnosis
- Fatal Outcome
- Graft vs Host Disease/complications
- Humans
- Immunocompromised Host
- In Situ Hybridization
- Kidney Failure, Chronic/complications
- Kidney Transplantation
- Leukemia/complications
- Leukemia/therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/complications
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy
- Leukemia, Myeloid, Acute/complications
- Leukemia, Myeloid, Acute/therapy
- Male
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/complications
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy
- Viremia/diagnosis
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363
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Choi YJ, Jung WH, Jung SH, Park C. Clear cell sarcoma of the kidney--immunohistochemical study and flow cytometric DNA analysis of 7 cases. Yonsei Med J 1994; 35:336-43. [PMID: 7975743 DOI: 10.3349/ymj.1994.35.3.336] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Immunohistochemical study and flow cytometric DNA analysis were done on seven cases of clear cell sarcoma of the kidney (CCSK) to speculate its histogenesis and to access the diagnostic usefulness of these methods in the differential diagnosis of Wilm's tumor. Clinically, CCSK is a rare malignant renal tumor of children with a propensity to metastasize to bone. Arborizing vascular pattern surrounding the tumor cells which have clear cytoplasm is characteristic histologic finding. Immunohistochemically, only vimentin was diffusely demonstrated in the tumor cell membrane and cytoplasm. In flow cytometric DNA analysis, four cases showed diploidy and two cases near diploidy. CCSK is a separate disease entity with characteristic clinicopathologic, immunohistochemical and flow cytometric findings in distinction from Wilms' tumor. Considering the histologic and immunohistochemical findings, the possible histogenetic mechanism of CCSK seems to be in common with congenital mesoblastic nephroma (CMN), that is primitive mesenchymal cells which committed early stromagenic activity.
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364
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Choi YJ, Kim TS. Malignant fibrous histiocytoma in chordoma--immunohistochemical evidence of transformation from chordoma to malignant fibrous histiocytoma. Yonsei Med J 1994; 35:239-43. [PMID: 8091802 DOI: 10.3349/ymj.1994.35.2.239] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Sarcomatous transformation in chordoma (dedifferentiated chordoma) is a very rare condition and has been emphasized as a distinct entity because of its more aggressive clinical course. Here we describe a case of dedifferentiated chordoma (chordoma associated with malignant fibrous histiocytoma) arising from the sacrococcygeal region of a 55-year-old woman. The results of immunohistochemical stain in the chordoma area were strong positive for cytokeratin, epithelial membrane antigen and S-100 protein. The spindle and giant cells in the transitional areas of chordoma and malignant fibrous histiocytoma were positive for cytokeratin and epithelial membrane antigen in addition to vimentin and alpha-1-antichymotrypsin. The spindle and giant cells in the central area of malignant fibrous histiocytoma were negative for cytokeratin and epithelial membrane antigen, but positive for vimentin and alpha-1-antichymotrypsin. This supports the pathogenesis of sarcomatous transformation from chordoma.
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365
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Roh SG, Baik MG, Woo JH, Choi YJ. Non-hormonal factors on differentiation of bovine mammary cells. In Vitro Cell Dev Biol Anim 1994; 30A:292-4. [PMID: 7520811 DOI: 10.1007/bf02631448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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366
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Choi YJ, Kang CS, Shin WS, Jee MK, Kim BK, Kim SM, Shim SI. Epstein-Barr virus associated posttransplant malignant lymphoma in renal allograft recipients. J Korean Med Sci 1994; 9:162-8. [PMID: 7986391 PMCID: PMC3053944 DOI: 10.3346/jkms.1994.9.2.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We report two cases of posttransplant malignant lymphoma(PTML) of B cell origin associated with Epstein-Barr virus(EBV) infection. They were a 52-year-old male and a 37 year-old-female, in whom intermediate-grade diffuse malignant lymphomas of large cell type developed in the submandibular area and jejunum, respectively. DNA and RNA in situ hybridization revealed the presence of EBV-specific DNA and RNA sequences in the tumor cells.
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367
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Roh SG, Baik MG, Choi YJ. The effect of lactogenic hormones on protein synthesis and amino acid uptake in rat mammary acinar cell culture at various physiological stages. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1994; 26:479-85. [PMID: 8013731 DOI: 10.1016/0020-711x(94)90003-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
1. The activities of protein synthesis and amino acid uptake at various physiological stages were determined by the incorporation of radioactive materials ([3H]-lysine, [14C]-cycloleucine) in rat mammary epithelial cell cultures. The activity of protein synthesis and amino acid uptake was higher in early lactation than in virgin, pregnant and late lactation stages. 2. Lactogenic hormones (prolactin, hydrocortisone and insulin) treatment related with mammary growth and differentiation increased the activities of protein synthesis and amino acid uptake. But increase of these activities was different at each physiological stage. 3. The effect of prolactin and hydrocortisone on the activities were greater in virgin, pregnant and late lactation than in early lactation. And effect of insulin was greater in pregnant and early lactation than in virgin and weanling.
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368
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Kim YS, Choi YJ, Jin DC, Chang YS, Yoon YS, Bang BK. Effect of long-term administration of somatostatin analogue on renal enlargement in uninephrectomized-diabetic rats. J Korean Med Sci 1993; 8:127-34. [PMID: 8397929 PMCID: PMC3053864 DOI: 10.3346/jkms.1993.8.2.127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Recent study has demonstrated that the long-acting somatostatin analogue administration effectively prevented initial renal growth in diabetic and uninephrectomized rats. In the present study we examined long-term effect of somatostatin analogue (Sandostatin) on renal enlargement in uninephrectomized-diabetic rat5. Animals were divided into 4 groups: (1) normal control rats (C) (n = 7), (2) uninephrectomized rats (NPX) (n = 7), (3) uninephrectomized-diabetic rats (NPX + DM) (n = 7) and (4) NPX + DM rats treated with Sandostatin (NPX + DM + Tx) (n = 9). All animals had free access to diet (50% protein) and water during the experimental period. To the NPX + DM + Tx rats, 2.5 micrograms of Sandostatin was given subcutaneously twice a day for 8 weeks. Periodic observations were done at 0, 4 and 8 weeks. After 8 weeks. NPX rats (0.540 +/- 0.017 (SEM)) had higher fractional kidney weights (FKW) (wet kidney wt/body wt) compared to C rats (0.410 +/- 0.014) (p < 0.0005), and both NPX + DM rats (0.983 +/- 0.098) and NPX + DM + Tx rats (1.091 +/- 0.042) had higher FKW compared to C rats (p < 0.0001) and NPX rats (p < 0.005), respectively. But no significant change of FKW was observed between NPX + DM rats and NPX + DM + Tx rats. Systolic blood pressure, BUN, serum creatinine, glomerular filtration rate and 24 hour urine protein excretion in NPX + DM rats were not different from those in NPX + DM + Tx rats.(ABSTRACT TRUNCATED AT 250 WORDS)
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369
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Cho MJ, Gal SW, Choi YJ, Yoon HW, Kim CY, Hong JC, Bahk JD. Overproduction of indole acetic acid in Azospirillum lipoferum using the Escherichia coli trp operon. MICROBIAL RELEASES : VIRUSES, BACTERIA, FUNGI 1993; 1:197-202. [PMID: 8281358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A recombinant plasmid carrying the trp operon from Escherichia coli, which synthesizes tryptophan from chorismate, was constructed by using a broad host range plasmid vector pRK290; a mutant trp plasmid for tryptophan overproduction was then selected. The physiological, biochemical, and genetic properties of the Azospirillum lipoferum KY6, a potential nitrogen fixer of rice, harbouring the recombinant trp plasmid pMJC1 and its mutant pMJC101, were compared with those of the wild-type bacteria. Anthranilate synthetase is known to be the trpE gene product which plays a key role in the regulatory step in the feedback control of tryptophan biosynthesis. The enzyme activity of the Azospirillum lipoferum KY6 carrying pMJC1 or pMJC101 was respectively 7- and 30-fold higher than that of the wild type in the presence of 10(-4)M tryptophan. As expected, the amount of tryptophan biosynthesis in A. lipoferum KY6 (pMJC101) was increased approximately 100-fold as compared with the wild type, which led to overproduction of indole acetic acid even without addition of exogenous tryptophan. Moreover, the recombinant trp plasmid was fairly stable in A. lipoferum KY6 host, showing only 25% loss of the plasmid itself or the trp insert after 40 generations.
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370
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Choi YJ, Yang KH, Gang SJ, Kim BK, Kim SM. Malignant glomus tumor originating in the superior mediastinum--an immunohistochemical and ultrastructural study. J Korean Med Sci 1991; 6:157-63. [PMID: 1661115 PMCID: PMC3049689 DOI: 10.3346/jkms.1991.6.2.157] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
An extremely rare case of malignant glomus tumor originating in the superior mediastinum was evaluated immunohistochemically and ultrastructurally. A 78-year-old woman who had been suffering from dysphagia and dyspnea had poorly-defined soft tissue mass, 4.5 x 2.5cm, in the superior mediastinum with direct invasion into the esophagus, trachea, and bilateral thyroid glands. This case is believed to be unique in several respects. There were neither recognizable findings of benign glomus tumor nor sarcomatous areas, in contrast to the previously reported cases. A definite direct invasion into the surrounding organs was identified. We therefore interpreted this case as primary malignant glomus tumor, not as glomangiosarcoma arising in a benign glomus tumor.
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371
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Choi YJ. Detection of human papillomavirus DNA on routine Papanicolaou's smears by in situ hybridization with the use of biotinylated probes. Am J Clin Pathol 1991; 95:475-80. [PMID: 1849699 DOI: 10.1093/ajcp/95.4.475] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Specific human papillomavirus (HPV) types have been implicated as playing a major role in the development of cervical neoplasias. HPV DNA types usually have been identified by nucleic acid hybridization assays with the use of radiolabeled probes. These techniques are sensitive and specific but are not suitable for large-scale clinical use. To detect specific HPV DNAs simply and rapidly, in situ hybridization (ISH) with the use of biotinylated HPV DNA 6/11 and 16/18 probes was done on destained Papanicolaou's (Pap) smears from 545 patients. All smears showed koilocytotic changes. HPV DNAs were demonstrated not only in cervical intraepithelial neoplasia (CIN) and atypia, but also in squamous cells with minimal nuclear changes (karyomegaly) and perinuclear halos. HPV DNA 16/18 was detected in 52% of the smears with CIN I, 44% of those with CIN II and III, 19% of those with atypia, and 4% of the minimal changes. HPV DNA 6/11 was detected in 27% of the smears with CIN I, 27% of those with atypia, and 6% of the minimal changes. HPV DNAs were also detected in smears without koilocytotic changes. Thus, ISH with the use of biotinylated probes can serve as an adjunct to Pap smears in detecting HPV infection.
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372
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Choi YJ. In situ hybridization using a biotinylated DNA probe on formalin-fixed liver biopsies with hepatitis B virus infections: in situ hybridization superior to immunochemistry. Mod Pathol 1990; 3:343-7. [PMID: 2194215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In situ hybridization (ISH) using a biotinylated hepatitis B virus (HBV) DNA probe was compared with immunohistochemistry (IHC) using antibody to HBsAg in liver biopsies of 98 patients with HBV-related hepatitis. The positive reaction for ISH and/or IHC was demonstrated in 83 cases from 98 cases studied. In 60 cases, the findings of ISH and IHC were concordant, and in 20 cases, ISH showed evidence of HBV infection by detecting HBV DNA, but IHC did not. The study here confirms the advantages of ISH detecting HBV-DNA over IHC detecting HBsAg. Since ISH using biotinylated probe is simple and rapid, it may be used as a routine diagnostic procedure.
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Abstract
The objectives were to examine the rate of synthesis of casein mRNA transcripts in bovine mammary tissue at different hormonal states and to study the effects of hormonal stimuli (insulin, hydrocortisone, and prolactin) on the accumulation of casein mRNA and on the rate of protein secretion by epithelial cells from bovine mammary tissues. Total cytoplasmic RNA was extracted from mammary tissues of cows obtained by biopsy (8 mo pregnant) and upon slaughter (lactating). The relative specific activities of cytoplasmic mRNA for alpha s1-, alpha s2-, beta-, and kappa-casein were about 3.2, 4.6, 3.3, and 4.5-fold higher in tissues of lactating cows than in those of 8 mo pregnant cows. Mammary alveolar epithelial cells retained hormone-inducible milk protein gene expression for total milk protein gene expression for total milk protein secretion and for alpha s1- and beta-casein messages. Prolactin, even in the absence of insulin and hydrocortisone, induced significant amounts of milk protein mRNA. Hydrocortisone in the presence of prolactin amplified the lactogenic effects on mammary epithelium. Maximal induction of beta-casein mRNA and protein secretion occurred when all three hormones were present.
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374
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Park CS, Choi YJ, Keller WL, Harrold RL. Effects of compensatory growth on milk protein gene expression and mammary differentiation. FASEB J 1988; 2:2619-24. [PMID: 2454864 DOI: 10.1096/fasebj.2.10.2454864] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
This experiment was conducted to develop an understanding of mechanisms responsible for effects of a compensatory (stair-step) growth pattern on the expression of milk protein genes and mammary differentiation. One hundred thirty weanling female rats were randomly assigned to either a control or a test group (compensatory growth). Early lactating mammary tissues from the compensatory growth group showed an increase in the RNA:DNA ratio, protein:DNA ratio, DNA, RNA, and protein while exhibiting a decrease in the lipid content as compared with those of the control group (2.2, 1.6, 1.7, 3.8, 2.8, and 0.5 times, respectively). Mammary tissues from the compensatory growth group contained about 1.1- to 1.4-fold more total cytoplasmic mRNA for caseins and whey acidic protein than those of the control group. The compensatory growth pattern increased beta-casein mRNA accumulation, milk protein secretion, and amino acid uptake in mammary acinar culture (1.3, 1.3, and 1.1 times, respectively) compared with those of the control group. These results indicate that the compensatory growth pattern increases milk protein mRNA transcripts and may contribute to an increase in the functional activity of the mammary gland.
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375
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Park CS, Erickson GM, Choi YJ, Marx GD. Effect of compensatory growth on regulation of growth and lactation: response of dairy heifers to a stair-step growth pattern. J Anim Sci 1987; 64:1751-8. [PMID: 3597190 DOI: 10.2527/jas1987.6461751x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The primary objective of this study was to improve the productive efficiency of growth via optimal use of both high fiber-low quality and high energy-high protein feeds in diets for growing dairy cattle. Twenty Holstein heifers were randomly assigned to either a control or treatment group. The control diet met the National Research Council (NRC) requirement for .45 kg/d gain, with heifers calving at 24 to 26 mo of age. The test groups were fed according to a 5-2-5-2 mo schedule in which the nutrient density was alternately 15% below or 40% above the NRC requirement. Results showed that the heifers on the test dietary regimen (compensatory growth) gained more and consumed less, resulting in significantly improved efficiency of growth (body gain/dry matter intake X 100), energy (body gain X 1,000/metabolizable energy (ME) intake) and protein utilization (body gain/protein intake X 100) in comparison to control animals (13.0 vs 7.3%; 57.9 vs 32.6 g/Mcal ME; 96.5 vs 54.2%, respectively). Marked changes in average concentration of urea-N, glucose, triglycerides, cholesterol and lecithin cholesterol acyltransferase activity in blood were seen for test heifers during the stair-step growth phase (i.e., alternating maintenance and compensatory). Evidence from this experiment suggests that the phased growth (stair-step) system offers a simple, practical and cost-effective method for raising dairy heifers.
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