151
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Lee MY, Chung JH, Shin JH, Hwang TJ, Kim KS, Lee JH, Nam JH, Lee MC, Park CS, Juhng SW, Choi C. Lymphonodular cryptococcosis diagnosed by fine needle aspiration cytology in hyper-IgM syndrome. A case report. Acta Cytol 2001; 45:241-4. [PMID: 11284311 DOI: 10.1159/000327282] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Most cases of cryptococcosis are diagnosed when signs of meningitis have appeared. We report a case of lymphonodular cryptococcosis that was diagnosed by fine needle aspiration cytology (FNAC), excisional biopsy of a cervical lymph node and culture of aspirated material. CASE An 11-year-old boy presented with a history of fever and enlarged bilateral cervical lymph nodes of two weeks' duration. Past medical history included immunoglobulin replacement for hyper-IgM syndrome for the previous eight years. FNAC smears from a cervical lymph node showed numerous yeasts of various sizes, ranging from 5 to 15 microns in diameter, located in the cytoplasm of multinucleated giant cells and in the background. In air-dried, Diff-Quik-stained slides, the yeasts stained blue and were surrounded by clear halos. Aspirated material collected in the syringe was cultured, and Cryptococcus neoformans was isolated. CONCLUSION This case report suggests that a combination of FNAC and culture is a simple and useful method of diagnosing fungal infections. Early diagnosis by FNAC makes possible the early initiation of treatment.
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152
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Lu TH, Shau WY, Shih TP, Lee MC, Chou MC, Lin CK. Factors associated with errors in death certificate completion. A national study in Taiwan. J Clin Epidemiol 2001; 54:232-8. [PMID: 11223320 DOI: 10.1016/s0895-4356(00)00299-7] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
To identify characteristics of certifying physicians and the deceased that are associated with errors in death certificate completion in Taiwan, we retrospectively reviewed 4123 systematically sampled death certificates issued in 1994. Multivariate analyses were used to assess the associations of various characteristics of the certifying physicians and the deceased with four types of error. Of the 4123 death certificates reviewed, 2525 (61%) were completed correctly. In 289 (7%), only the mechanism(s) of death was given (Major Error 1); in 146 (4%), multiple causal sequences were given in part I (Major Error 2); in 800 (19%), a single causal sequence was given but was not specific enough (Minor Error 1); and in 363 (9%), a single causal sequence was given but the order was incorrect (Minor Error 2). Multiple logistic regression analyses revealed that the probability of error in death certification increased as the age of the deceased increased, the age of the certifier decreased, and the level of the hospital decreased. These findings suggest that training in death certificate completion should focus on younger certifiers and those working at lower level teaching hospitals and nonteaching hospitals. Given the high rate of Minor Error 1, physicians should be reminded to state information as specifically as possible to render cause-of-death statistics more informative.
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Schirra HJ, Scanlon MJ, Lee MC, Anderson MA, Craik DJ. The solution structure of C1-T1, a two-domain proteinase inhibitor derived from a circular precursor protein from Nicotiana alata. J Mol Biol 2001; 306:69-79. [PMID: 11178894 DOI: 10.1006/jmbi.2000.4318] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A two-domain portion of the proteinase inhibitor precursor from Nicotiana alata (NaProPI) has been expressed and its structure determined by NMR spectroscopy. NaProPI contains six almost identical 53 amino acid repeats that fold into six highly similar domains; however, the sequence repeats do not coincide with the structural domains. Five of the structural domains comprise the C-terminal portion of one repeat and the N-terminal portion of the next. The sixth domain contains the C-terminal portion of the sixth repeat and the N-terminal portion of the first repeat. Disulphide bonds link these C and N-terminal fragments to generate the clasped-bracelet fold of NaProPI. The three-dimensional structure of NaProPI is not known, but it is conceivable that adjacent domains in NaProPI interact to generate the circular "bracelet" with the N and C termini in close enough proximity to facilitate formation of the disulphide bonds that form the "clasp". The expressed protein, examined in the current study, comprises residues 25-135 of NaProPI and encompasses the first two contiguous structural domains, namely the chymotrypsin inhibitor C1 and the trypsin inhibitor T1, joined by a five-residue linker, and is referred to as C1-T1. The tertiary structure of each domain in C1-T1 is identical to that found in the isolated inhibitors. However, no nuclear Overhauser effect contacts are observed between the two domains and the five-residue linker adopts an extended conformation. The absence of interactions between the domains indicates that adjacent domains do not specifically interact to drive the circularisation of NaProPI. These results are in agreement with recent data which describe similar PI precursors from other members of the Solanaceae having two, three, or four repeats. The lack of strong interdomain association is likely to be important for the function of individual inhibitors by ensuring that there is no masking of reactive sites upon release from the precursor.
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Jeong JM, Kim YJ, Lee YS, Ko JI, Son M, Lee DS, Chung JK, Park JH, Lee MC. Lipiodol solution of a lipophilic agent, (188)Re-TDD, for the treatment of liver cancer. Nucl Med Biol 2001; 28:197-204. [PMID: 11295430 DOI: 10.1016/s0969-8051(00)00208-0] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Radiolabeled lipiodol has been used for targeting liver cancer. We developed a lipiodol solution of (188)Re-TDD (2,2,9,9-tetramethyl-4,7-diaza-1,10-decanedithiol) and investigated its feasibility for the treatment of liver cancer. The lipiodol solution of (188)Re-TDD was well-retained in the lipiodol phase in vitro. After injection through the tail veins of mice, high lung-uptake was investigated which is evidence of embolizing activity. We also found high accumulation in hepatoma after injection through the hepatic arteries of hepatoma-bearing rats. In conclusion, the lipiodol solution of (188)Re-TDD is a promising agent for liver cancer therapy.
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155
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Yeo JS, Chung JK, So Y, Kim S, Lee E, Lee DS, Youn YK, Hong SJ, Ahn IM, Lee MC, Cho BY. F-18-fluorodeoxyglucose positron emission tomography as a presurgical evaluation modality for I-131 scan-negative thyroid carcinoma patients with local recurrence in cervical lymph nodes. Head Neck 2001; 23:94-103. [PMID: 11303639 DOI: 10.1002/1097-0347(200102)23:2<94::aid-hed1004>3.0.co;2-r] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND F-18-labeled fluorodeoxyglucose-positron emission tomography (FDG-PET) has a supplementary role in localizing recurrent sites of differentiated thyroid carcinoma. We evaluated whether FDG-PET is feasible as a presurgical evaluation modality for I-131 scan-negative thyroid carcinoma patients. METHODS Preoperative FDG-PET results were compared with the pathologic findings of lymph nodes specimens of 22 papillary thyroid patients. All patients had thyroidectomy and I-131 ablation therapy beforehand and showed negative I-131 scans on follow-up studies. RESULTS In 85 cervical lymph node groups dissected, 56 lymph node groups revealed metastasis. The sensitivity and specificity of FDG PET for metastasis were 80% (45 of 56) and 83% (24 of 29), respectively. Among the pathologically positive 33 lymph nodes with normal size(< or =1 cm), FDG-PET detected 23 nodes. Serum thyroglobulin levels were elevated in 12 patients (sensitivity, 55%). CONCLUSION FDG-PET accurately detected the recurred cervical lymph nodes of differentiated thyroid carcinoma patients who showed negative I-131 scan. FDG-PET is suitable for the presurgical evaluation of these patients.
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156
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Lee DS, Lee JS, Oh SH, Kim SK, Kim JW, Chung JK, Lee MC, Kim CS. Cross-modal plasticity and cochlear implants. Nature 2001; 409:149-50. [PMID: 11196628 DOI: 10.1038/35051653] [Citation(s) in RCA: 274] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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157
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Lee JK, Lee JH, Kim SH, Lee MC. Distal anterior choroidal artery aneurysm in a patient with moyamoya disease: case report. Neurosurgery 2001; 48:222-5. [PMID: 11152352 DOI: 10.1097/00006123-200101000-00043] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE AND IMPORTANCE Distal anterior choroidal artery (AChA) aneurysms in moyamoya disease are rare, with few surgically verified reported cases. CLINICAL PRESENTATION We report a rare case of distal AChA aneurysm associated with moyamoya disease in a 48-year-old man who presented with vomiting and severe headache. Computed tomographic scans revealed an intracerebral hematoma in the right temporoparietal lobe and a diffuse intraventricular hemorrhage. INTERVENTION The hematoma was removed via computed tomography-guided stereotactic aspiration and ventricular drainage. Cerebral angiography showed a saccular aneurysm located at the distal branch of the right AChA. By means of magnetic resonance imaging, a small signal void lesion was detected in the periventricular area lateral to the trigone of the right lateral ventricle. The aneurysm was accurately accessed via a parietal cortical incision by use of magnetic resonance imaging-guided stereotactic localization. The aneurysm was successfully resected after undergoing trapping of the parent artery, and when the patient was discharged, he had no evidence of neurological deficit. The aneurysm was histologically verified to be a true aneurysm. CONCLUSION Direct surgery should be considered in cases of ruptured distal AChA aneurysms located in the periventricular or intraventricular regions.
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158
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Kim HJ, Lee WH, Yoon CH, Jeong JC, Nam KS, Kim HM, Choo YK, Lee MC, Kim CH. Bombycis corpus extract prevents amyloid-beta-induced cytotoxicity and protects superoxide dismutase activity in cultured rat astrocytes. Pharmacol Res 2001; 43:11-6. [PMID: 11207060 DOI: 10.1006/phrs.2000.0746] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Bombycis corpus(BC) or Bombyx Batryticatus, a batryticated silkworm and white-stiff silkworm, is a drug consisting of the dried larva of silkworm, Mobyz mori L., dead and stiffened due to the infection of Beauveria (Bals.) Vuill. In the present study, we have examined the protective effect of the water extracts against Amyloid- beta(A beta) 25-35 peptide-induced cytotoxicity by microscopic observation and LDH assay, and its action on antioxidative enzymes using cultured astrocyte cells. A beta 25-35-induced cell death was protected by the application of water extract of BC in a dose-dependent manner, and concentrations of 10(-6)to 10(-7)g ml(-1)showed a significant effect compared to exposure of A beta 25-35 alone. When antioxidative enzyme activities such as catalase, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione-S transferase (GST) were assayed after A beta 25-35 treatment, most enzyme activities were decreased in a similar fashion. BC treatment of A beta 25-35-treated astrocytes did not affect the enzyme activities of catalase, GSH-Px and GST. However, only SOD activity was enhanced by BC treatment and this may result from the potentiation of the antioxidative ability of BC. The protective effect of BC against cytotoxicity induced by Abeta 25-35 strongly indicates that BC could be a protective agent for free radical generating compounds, and that Abeta 25-35 is not only a potent lipid peroxide inducer, but can also cause changes in antioxidative enzymes. From the results, it was concluded that BC has a protective effect against Abeta -induced cytotoxicity in cultured astrocyte cells through the inhibition of lipid peroxidation and protection of antioxidative enzymes.
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Adjeroh DA, Lee MC. On ratio-based color indexing. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 2001; 10:36-48. [PMID: 18249595 DOI: 10.1109/83.892441] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The color ratio approach to indexing has been found to be robust and effective in indexing image and video databases, in different color spaces, and when using transformed color features, such as those from the Karhunen-Loeve transform (KLT) or the discrete cosine transform (DCT). However, the reason for the superior performance of the color ratio model, especially on different color spaces or with transformed color features has, at best, been speculative. This paper develops a generalized form for the color ratio model, based on which we characterize the general distribution of the color ratios. From the distribution, we present a theory that explains and supports the performance of the color ratio approach in image and video indexing. It is shown that the same theory accounts for its effectiveness in different color spaces and in the transform domain. Some general problems encountered in using the original retinex lightness algorithm, and some other issues specific to ratio-based color indexing are discussed in the light of the theory. Results are presented which show that the proposed theory is supported by empirical evidence.
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160
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Kim YJ, Lee MC, Kim SJ, Chun JY. Identification and characterization of multiple isoforms of a mouse ribosome receptor. Gene 2000; 261:337-44. [PMID: 11167022 DOI: 10.1016/s0378-1119(00)00496-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We isolated multiple cDNA clones encoding various isoforms of a mouse ribosome receptor protein (mRRp). The cDNAs were isolated from a 13.5-day-old mouse conceptus cDNA library by polymerase chain reaction-based screening. The predicted proteins encoded by these cDNAs showed significant homology with ribosome receptors present in dogs (83%), humans (80%), and chickens (45%). The cDNA isoforms had highly identical N- and C-terminal sequences but differed in their central sequences, suggesting that these cDNA isoforms may be derived by alternative splicing from a single gene. Genomic Southern blot analysis confirmed the existence of only a single mouse ribosome receptor gene. Alignments of the deduced amino acid sequences of the mRRp cDNA isoforms revealed that they differ in the number of decapeptide repeats present in the central domain of the protein. These repeats have been previously suggested to mediate ribosome binding and thus differences in repeat number may translate to different ribosome binding abilities. The longest mRRp isoform had 61 tandem repeats. This is of interest because in the human and canine ribosome receptor proteins there are only 54 tandem repeats, suggesting that humans and dogs may also have larger ribosome receptor protein isoforms. Surprisingly, mRRp has a very short basic C-terminal sequence of only 35 amino acids, while in contrast, the known human and canine forms of this protein have acidic C-terminal regions comprised of 803 and 798 amino acid residues, respectively. Although the function of the C-terminal region is currently unknown, it may be that those C-terminal sequences that are present in human and canine RRp proteins but missing in mRRp do not play critical roles in RRp function. The cDNA of the ES/130 isoform, which lacks tandem repeats and presumably are unable to bind ribosomes, could be isolated by reverse transcriptase-PCR from E 13.5 mouse embryos. mRRp mRNAs were expressed in all tissues examined but expression levels of each isoform differed between tissues. The identification of multiple mRRp isoforms in the mouse will allow us to study the regulation and function of ribosome receptors on a genetic level.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Blotting, Northern
- Cell Line
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- Female
- Fetus
- Gene Expression
- Male
- Mice
- Molecular Sequence Data
- Protein Isoforms/genetics
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, Cytoplasmic and Nuclear/genetics
- Repetitive Sequences, Amino Acid
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Sequence Homology, Nucleic Acid
- Tandem Repeat Sequences
- Tissue Distribution
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Lee MC, Alpaugh ML, Nguyen M, Deato M, Dishakjian L, Barsky SH. Myoepithelial-specific CD44 shedding is mediated by a putative chymotrypsin-like sheddase. Biochem Biophys Res Commun 2000; 279:116-23. [PMID: 11112426 DOI: 10.1006/bbrc.2000.3918] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Our previous studies have demonstrated that myoepithelial cells, which surround incipient carcinomas in situ of the breast and other organs, exert antiinvasive and antiangiogenic effects in vitro through the elaboration of a number of different suppressor molecules among which include the shed membrane CD44. The present study addresses the mechanism of this myoepithelial CD44 shedding. This CD44 shedding is enhanced by PMA pretreatment, is specific for myoepithelial CD44, and inhibited by chymotrypsin-like inhibitors (chymostatin, alpha(1)-antichymotrypsin, TPCK, and SCCA-2) but not by trypsin-like inhibitors (TLCK), nor papain-like inhibitors (SCCA-1) nor hydroxamate-based or general metalloproteinase inhibitors (BB2516 (marimastat), 1,10-phenanthroline, and TIMP-1). The effect of PMA can be mimicked by exogenous chymotrypsin but not by other proteases. The CD44 shedding activity cannot be transferred by conditioned media, cell-cell contact, peripheral membrane, or integral membrane fractions. However, cell-free purified integral plasma membrane fractions obtained from myoepithelial cells pretreated with PMA also exhibit CD44 shedding which is inhibited by chymotrypsin-like inhibitors. These findings support the presence and activation of a putative chymotrypsin-like sheddase as the mechanism of CD44 shedding in myoepithelial cells.
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162
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Lee MC, Jiang SB, Ma CM. Monte Carlo and experimental investigations of multileaf collimated electron beams for modulated electron radiation therapy. Med Phys 2000; 27:2708-18. [PMID: 11190954 DOI: 10.1118/1.1328082] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Modulated electron radiation therapy (MERT) has been proposed as a means of delivering conformal dose to shallow tumors while sparing distal structures and surrounding tissues. Conventional systems for electron beam collimation are labor and time intensive in their construction and are therefore inadequate for use in the sequential delivery of multiple complex fields required by MERT. This study investigates two proposed methods of electron beam collimation: the use of existing photon multileaf collimators (MLC) in a helium atmosphere to reduce in-air electron scatter, and a MLC specifically designed for electron beam collimation. Monte Carlo simulations of a Varian Clinac 2100C were performed using the EGS4/BEAM system and dose calculations performed with the MCDOSE code. Dose penumbras from fields collimated by photon MLCs both with air and with helium at 6, 12, and 20 MeV at a range of SSDs from 70 to 90 cm were examined. Significant improvements were observed for the helium based system. Simulations were also performed on an electron specific MLC located at the level of the last scraper of a 25x25 cm2 applicator. A number of leaf materials, thicknesses, end shapes, and widths were simulated to determine optimal construction parameters. The results demonstrated that tungsten leaves 15 mm thick and 5 mm wide with unfocused ends would provide sufficient collimation for MERT fields. A prototype electron MLC was constructed and comparisons between film measurements and simulation demonstrate the validity of the Monte Carlo model. Further simulations of dose penumbras demonstrate that such an electron MLC would provide improvements over the helium filled photon MLC at all energies, and improvements in the 90-10 penumbra of 12% to 45% at 20 MeV and 6 MeV, respectively. These improvements were also seen in isodose curves when a complex field shape was simulated. It is thus concluded that an MLC specific for electron beam collimation is required for MERT.
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163
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Yoon SN, Lee DS, Chung JK, Lee MC. Comparative study of single-injection, single-acquisition 99mTc-MIBI gated SPET and stress-rest perfusion SPET for the evaluation of myocardial viability after bypass surgery in coronary artery disease. EUROPEAN JOURNAL OF NUCLEAR MEDICINE 2000; 27:1747-53. [PMID: 11189935 DOI: 10.1007/s002590000386] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In patients without previous myocardial infarction, the single-injection stress perfusion/rest function (SISPRF) approach using stress technetium-99m methoxyisobutylisonitrile (MIBI) gated single-photon emission tomography (SPET) can substitute for conventional stress-rest myocardial perfusion imaging for the assessment of myocardial viability. This study compared pre-operative single-injection, single-acquisition 99mTc-MIBI gated SPET and conventional stress-rest imaging for the prediction of myocardial viability in patients who underwent coronary artery bypass surgery (CABG). Rest thallium-201 SPET followed by stress 99mTc-MIBI gated SPET was performed in 20 patients [nine with previous myocardial infarction (MI) and 11 without previous MI). The study was performed before and 3 months after CABG, and viability assessment was validated by wall motion improvement after CABG. A four-point scoring system (0-3 for normal to absent tracer uptake) for 17 segments of the left ventricular myocardium was used for the assessment of stress and rest uptake. Wall motion, wall thickening and perfusion status were analysed by semi-quantitative visual assessment. On gated SPET, perfusion defect reversibility was considered present when a definite perfusion defect was observed and wall motion or thickening was normal or showed only a mild decrease. In patients with a previous MI, the left ventricular ejection fraction improved significantly after CABG (46% +/- 7% vs 42% +/- 11% before CABG, P < 0.05). In patients without previous MI, the ejection fraction improved significantly after CABG (50 +/- 12% vs 44% +/- 16% before CABG, P<0.05). In patients with previous MI, positive predictive values using the stress-rest reversibility and SISPRF approaches were 91% and 90%, respectively, and corresponding negative predictive values were 25% and 18%. In patients without previous MI, positive predictive values using the stress-rest and SISPRF approaches were 70% and 61%, respectively, and corresponding negative predictive values were 63% and 14%. It is concluded that SISPRF SPET study is of similar value to conventional stress-rest perfusion study in predicting wall motion improvement in patients with a previous MI, but that it is of limited value in predicting the myocardial viability of patients without previous MI, owing to a lower predictive value.
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Lee DS, Cheon GJ, Ahn JY, Chung JK, Lee MC. Reproducibility of assessment of myocardial function using gated 99Tc(m)-MIBI SPECT and quantitative software. Nucl Med Commun 2000; 21:1127-34. [PMID: 11200017 DOI: 10.1097/00006231-200012000-00006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE We investigated the reproducibility of the quantification of left ventricular volumes and ejection fraction, and grading of myocardial wall motion and systolic thickening with gated myocardial single-photon emission computed tomography (SPECT) and Cedars quantification software. PATIENTS, MATERIALS AND METHODS We performed post-stress gated myocardial SPECT in 33 consecutive patients twice sequentially in situ. Sixteen frames per cycle were used for gating. Using Cedars quantitative gated SPECT software ventricular volumes and ejection fraction (EF) were calculated. Wall motion and thickening was graded using 5- and 4-point scores, respectively. Coefficients of variation for re-examination of volumes and EF were calculated. Kappa values for assessing reproducibility of wall motion or wall thickening were calculated. RESULTS Root mean square of errors was 5.0 ml for end-diastolic volume, 3.9 ml for end-systolic volume and 1.9% for EF. No bias or difference was found between the first and second acquisition by Bland-Altman analysis. Kappa values for wall motion and thickening of repeated acquisition was 0.76 and 0.87, respectively. The value of 2 SD from Bland-Altman analysis was 14.4 ml for EDV, 11.2 ml for ESV and 5.3% for EF. CONCLUSION We conclude that quantification of functional indices and assessment of wall motion or thickening using gated 99Tc(m)-sestamibi (MIBI) SPECT was reproducible and we found that their ranges of physiological fluctuation were narrow enough.
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165
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Alpaugh ML, Lee MC, Nguyen M, Deato M, Dishakjian L, Barsky SH. Myoepithelial-specific CD44 shedding contributes to the anti-invasive and antiangiogenic phenotype of myoepithelial cells. Exp Cell Res 2000; 261:150-8. [PMID: 11082285 DOI: 10.1006/excr.2000.5056] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Myoepithelial cells surround incipient ductal carcinomas of the breast and exert anti-invasive and antiangiogenic effects in vitro through the elaboration of suppressor molecules. This study examines one putative molecule, solubilized CD44 produced by myoepithelial shedding of membrane CD44. Studies with different human myoepithelial cell lines demonstrate that myoepithelial cells express and shed both the 85-kDa standard (CD44s) and the 130-kDa epithelial (CD44v8-10) isoforms, findings further confirmed by the use of isoform-specific antibodies. PMA pretreatment enhances CD44 shedding detected by two different methods at different time points: a reduction in surface CD44 at 2 h by flow cytometry and a marked decrease in both total cellular CD44 and plasma membrane CD44 at 12 h by Western blot. This shedding is both specific for CD44 and specific for myoepithelial cells. This shedding is inhibited by the chymotrypsin inhibitors chymostatin and alpha(1)-antichymotrypsin but not by general metallo-, cysteine, or other serine proteinase inhibitors. Myoepithelial-cell-conditioned medium and affinity-purified solubilized CD44 from this conditioned medium block hyaluronan adhesion and migration of both human carcinoma cell lines and human umbilical vein endothelial cells.
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166
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Chung SJ, Kim JS, Lee MC. Syndrome of cerebral spinal fluid hypovolemia: clinical and imaging features and outcome. Neurology 2000; 55:1321-7. [PMID: 11087775 DOI: 10.1212/wnl.55.9.1321] [Citation(s) in RCA: 166] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To investigate clinical, MRI, and radioisotope findings and therapeutic outcome of the syndrome of CSF hypovolemia. METHODS Retrospective review was performed of 30 consecutive patients (10 men, 20 women; mean age 37 years) with the syndrome of CSF hypovolemia. RESULTS All patients had an orthostatic headache, which was alleviated to a variable extent on recumbency. Additional clinical symptoms included nausea, dizziness, neck stiffness, blurring of vision, tinnitus, plugged ear, hearing difficulties and radicular pain of the arm. Eighty-two percent of the patients had CSF opening pressure less than 60 mm H2O, 59% had CSF pleocytosis, and 95% had increased CSF protein. Brain MRI showed diffuse pachymeningeal gadolinium enhancement on T1-weighted image in 83%, which was seen as hyperintense signals on T2-weighted imaging. Other features included subdural hematoma/hygroma in 17% and descent of the brain in 48% of the patients. Radioisotope cisternographic results identified CSF leakage sites in 52%, most often at the lumbar region. Also observed were limited ascent of the tracer to the cerebral convexity (91%), early appearance of radioisotope in the bladder (65%), and early soft tissue uptake of radioisotope (43%). Epidural blood patches were performed in 23 patients, which produced complete resolution of headaches in 70%. Two patients underwent drainage of subdural hematoma. None died or were disabled during hospitalization. CONCLUSIONS Patients with CSF hypovolemia frequently have distinct MRI and radioisotope cisternographic abnormalities and often respond favorably to an epidural blood patch.
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167
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Lee MC, Lin LH. Ultrasound screening of neonatal adrenal hemorrhage. ACTA PAEDIATRICA TAIWANICA = TAIWAN ER KE YI XUE HUI ZA ZHI 2000; 41:327-30. [PMID: 11198940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Neonatal adrenal hemorrhage (NAH) is frequently overlooked because the majority of cases are asymptomatic. In this study, we investigated the clinical symptoms, echographic characteristics and incidence of NAH from January 1998 to December 1999 at Cathay General Hospital, Taipei, Taiwan. Among 3273 newborns who had ultrasound screening, 18 cases were diagnosed as having NAH. The incidence was 0.55% which was compatible with other reports. But there was a female predominance (10:8) which was different from previous reports. Only one premature baby was diagnosed with NAH. No patients had perinatal asphyxia, and this was different from other reports. The mean birth body weight was 3530 grams which was more than the 75th percentile of normal term baby birth weight. Sixteen cases had right-sided NAH and two cases had left-sided NAH. Eleven cases (61%) within this study were asymptomatic. The incidence of pathologic jaundice was 11%. Four babies (22%) had poor oral feeding combined with vomiting. Only one had severe anemia for which blood transfusion was required. There were no cases of adrenocortical insufficiency in our study. Only one patient received adrenalectomy. In conclusion, NAH can be detected early by sonography and most cases require only supportive treatment. Thus, unnecessary surgery and severe complications due to delayed diagnosis can be avoided.
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168
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Jung S, Kim JH, Kim TS, Lee MC, Seo JJ, Park JW, Kang SS. Supradiaphragmatic ectopic adrenocorticotropic hormone-secreting adenoma. Pathol Int 2000; 50:901-4. [PMID: 11107067 DOI: 10.1046/j.1440-1827.2000.01145.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A 22-year-old woman with Cushing's syndrome, caused by an extremely rare suprasellar ectopic pituitary adenoma, is presented. Magnetic resonance imaging and computed tomography revealed a well-circumscribed mass in the right suprasellar region. Endocrinological tests showed elevated s-adrenocorticotropic hormone level and hypercortisolemia. The tumor was totally removed by right subfrontal approach. At the time of the operation, the tumor was in continuity with the distal pituitary stalk but not with the pituitary gland. The diaphragma sellae was intact. Histologic diagnosis of the tumor specimen was confirmed as a pituitary adenoma. After surgical removal of the tumor, continued improvement in the patient's laboratory results and disappearance of her endocrine symptoms strongly indicated the absence of adenoma cells in the pituitary gland or stalk. Six years post-surgery, there was no evidence of recurrence in the patient's clinical and laboratory examination. This tumor probably originated from aberrant anterior pituitary cells of the pituitary stalk.
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Cheng CH, Chen MY, Lee YJ, Lee MC, Shu KH, Wu MY, Lian JD. Assessment of nutritional status in continuous ambulatory peritoneal dialysis patients: a comparison of bioelectric impedance and conventional methods. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 2000; 63:758-64. [PMID: 11076433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
BACKGROUND Nutritional status is an important factor in long term continuous ambulatory peritoneal dialysis (CAPD) prognoses. Conventionally, serum albumin is an indicator of nutritional status. More recently, protein catabolic rate and lean body mass have been calculated during peritoneal equilibrium testing to assess nutritional status. These have the advantage of providing an early indication of malnutrition before the serum albumin decreases. Bioelectric impedance analysis (BIA) of nutrition has the advantage of being the simplest procedure among all nutritional assessments. Standard nutritional assessments was compared with the BIA method. METHODS The protein catabolic rate and lean body mass was measured by the Keshaviah method. At the same time BIA was used to assess lean body mass, fat mass and fixed percentage of fat in 27 long-term CAPD patients, with and without peritoneal fluids. RESULTS Among the 27 patients, the protein catabolic rate was 0.95+/-0.5 g/kg/day and lean body mass was 37.4+/-0.5 kg measured by the conventional method. Using BIA, the lean body mass was 37.8+/-11.0 kg with peritoneal dialysate, which was strongly correlated with the conventional method (p<0.001). BIA of lean body mass was 37.4+/-9.2 kg without peritoneal dialysate, which was also significantly correlated to the conventional method (p<0.001). CONCLUSIONS BIA nutritional assessment of lean body mass was comparable to the conventional method of nutritional assessment. The presence or absence of peritoneal dialysate did not influence the BIA method for detection of lean body mass. BIA has the advantage of being a more simple procedure and can be used for the long-term assessment of nutritional status in CAPD patients.
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170
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Wang SL, Pan WH, Lee MC, Cheng SP, Chang MC. Predictors of survival among elders suffering strokes in Taiwan: observation from a nationally representative sample. Stroke 2000; 31:2354-60. [PMID: 11022063 DOI: 10.1161/01.str.31.10.2354] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Cerebrovascular disease was the leading cause of death in Taiwan from 1963 to 1982. Deaths due to stroke now rank second only to cancer, with more deaths resulting from strokes than from any other single pathology. It is important to understand stroke prognosis among elderly stroke survivors, with respect to survival and attendant predictive factors, because aged population in Taiwan is growing rapidly. The aim of the present study was to discern factors affecting survival in stroke patients from a nationally representative elderly sample. METHODS A total of 99 stroke survivors, from a representative national sample of elders aged >/=65 years on December 31, 1988, whose strokes occurred in the period 1989-1993, were followed for mortality until July 1, 1995. Personal data were gathered through home interviews conducted by well-trained community nurses, and mortality data were obtained from the national census office by using identification card numbers. Cox proportional hazards regression analysis and the stepwise technique were used to search for important prognostic factors of survival. RESULTS Women experienced a higher mortality rate (139.8 per 1000 person-years) than men (126.4 per 1000 person-years), as age-adjusted for World Health Organization world-population figures. Stroke patients who received continuous treatment for diabetes experienced mortality risks similar to those of patients without diabetes and much lower risks than those with discontinuous diabetes treatment. Cognitive impairment was also an independent predictor of survival (relative risk 2.69, P<0.05). In addition, patients with both cognitive and mobility impairments had a 2- to 3-fold greater risk of mortality than those with only a single abnormality. CONCLUSIONS This first report on the various prognostic factors related to survival of elderly stroke patients in Taiwan's Chinese population emphasized the benefit of continuous diabetes treatment in improving survival chances. These stroke patients should also be monitored for cognitive and mobility impairments and undergo rehabilitation.
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171
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Lee MC, Ma CM. Monte Carlo characterization of clinical electron beams in transverse magnetic fields. Phys Med Biol 2000; 45:2947-67. [PMID: 11049182 DOI: 10.1088/0031-9155/45/10/315] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Monte Carlo simulations were employed to study the characteristics of the electron beams of a clinical linear accelerator in the presence of 1.5 and 3.0 T transverse magnetic fields and to assess the possibility of using magnetic fields in conjunction with modulated electron radiation therapy (MERT). The starting depth of the magnetic field was varied over several centimetres. It was found that peak doses of as much as 2.7 times the surface dose could be achieved with a 1.5 T magnetic field. The magnetic field was shown to reduce the 80% and 20% dose drop-off distance by 50% to 80%. The distance between the 80% dose levels of the pseudo-Bragg peak induced by the magnetic field was found to be extremely narrow, generally less than 1 cm. However, by modulating the energy and intensity of the electron fields while simultaneously moving the magnetic field, a homogeneous dose distribution with low surface dose and a sharp dose fall-off was generated. Heterogeneities are shown to change the effective range of the electron beams, but not eliminate the advantages of a sharp depth dose drop-off or high peak-to-surface dose ratio. This suggests the applicability of MERT with magnetic fields in heterogeneous media. The results of this study demonstrate the ability to use magnetic fields in MERT to produce highly desirable dose distributions.
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Lee DS, Lee SK, Kim SK, Kang KW, Kang E, Lee KH, Hyun IY, Chung J, Lee MC. Late postictal residual perfusion abnormality in epileptogenic zone found on 6-hour postictal SPECT. Neurology 2000; 55:835-41. [PMID: 10994005 DOI: 10.1212/wnl.55.6.835] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Temporal evolution of regional hyperperfusion in the late postictal stage in epilepsy has not been clearly defined. OBJECTIVE To establish the late temporal evolution of the perfusion in epileptogenic zones using 6-hour postictal SPECT. METHODS Ictal 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO) SPECT was performed in 10 patients with intractable epilepsy (4 temporal lobe epilepsy, 6 neocortical epilepsy) followed by delayed acquisition and another 6-hour postictal SPECT after reinjection of 99mTc-HMPAO. The delayed acquired SPECT was subtracted from the reinjection SPECT to yield the 6-hour postictal SPECT. Interictal SPECT was acquired on another day. Late postictal perfusion was examined visually, and asymmetric indexes were compared with each other on ictal, 6-hour postictal, and interictal SPECT. RESULTS Ictal SPECT images of delayed acquisition were visually and quantitatively similar to those of early acquisition. In 7 of 10 patients, 6-hour postictal SPECT showed hyperperfusion. In one patient, the 6-hour postictal SPECT image showed less perfusion than the interictal SPECT image in the epileptogenic zone. CONCLUSIONS Late postictal hyperperfusion was found in more than half of the patients. Postictal perfusion abnormalities did not come back to the interictal phase 6 hours after ictus and these were identified on ictal/postictal 99mTc- HMPAO SPECT.
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Garcia JC, Newman AK, Liu JM, Lee MC. Cw mode-locked deep UV pulses at an average power of 1.8 W. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/1464-4258/2/6/101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Lee JK, Kim GH, Kim JS, Kim KK, Lee MC, Yoo HW. Identification of four novel mutations in five unrelated Korean families with Fabry disease. Clin Genet 2000; 58:228-33. [PMID: 11076046 DOI: 10.1034/j.1399-0004.2000.580311.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Fabry disease is a X-linked recessively inherited metabolic disorder, which results from the deficient activity of the lysosomal hydrolase alpha-galactosidase A leading to the systemic deposition of glycosphingolipids with terminal alpha-galactosyl moieties. Single-strand conformation polymorphism (SSCP) analysis was performed, followed by DNA sequencing of PCR amplified exons of the human alpha-galactosidase A gene in 5 unrelated Korean patients with classic Fabry disease. Five different mutations were identified; two nonsense mutations (Y86X and R342X), one missense mutation (D266N), and two small deletions (296del2 and 802del4). Except for R342X mutation, four were novel mutations (Y86X, D266N, 296del2, 802del4). A T to G transversion at nucleotide position 5157 in exon 2 caused a tyrosine-to-stop substitution at codon 86. A G to A transition at position 10287 in exon 5 substituted an asparagine for an aspartate at codon 266. Mutation 296del2 in exon 2 resulted in a frame shift with a stop signal at the 22th codon downstream from the mutation, whereas mutation 802del4 resulted in a stop codon at the site of 4 bp deletion. In addition, the 802del4 was found to be a de novo mutation. This is the first report on mutation analysis of the human alpha-galactosidase A gene in Korean patients with Fabry disease.
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Mess SE, Reese PP, Della Lana DF, Walley AY, Ives EP, Lee MC. Older, hypertensive, and hypercholesterolemic fairgoers visit more booths and differ in their health concerns at a community health fair. J Community Health 2000; 25:315-29. [PMID: 10941695 DOI: 10.1023/a:1005164427176] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The purpose of this study was to determine whether persons attending a community health fair had different health concerns and booth visitation patterns based on their risk factor profiles. All fairgoers were encouraged to complete an anonymous survey of demographic information, top 4 health concerns, and selected cardiac risk factors. Over the five-hour duration of the fair, 329 surveys were collected from about 450 fairgoers. There were no exclusion criteria for the survey. The fair was sponsored by the Maryland Chapter of the American College of Physicians, organized by medical students from the University of Maryland and Johns Hopkins University, and included 23 booths on a variety of health topics. Older fairgoers and fairgoers with a self-reported history of high blood pressure or elevated cholesterol showed an increased interest in hypertension and heart disease (p < 0.05). Older fairgoers also showed an increased interest in health topics related to aging, such as estrogen replacement therapy and geriatric medicine. Older, hypertensive and hypercholesterolemic fairgoers visited an increased mean number of total booths when compared to other respondents (p < 0.05). Most booths reported a higher percentage of older, hypertensive, and hypercholesterolemic visitors than the overall percentage of fairgoers who reported these risk factors. These results suggest that booth visitation patterns of health fair participants may be viewed as a deliberate attempt by at risk populations to access health information particular to their needs.
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