526
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Lee TH, Kato H, Pan LH, Ryu JH, Kogure K, Itoyama Y. Localization of nerve growth factor, trkA and P75 immunoreactivity in the hippocampal formation and basal forebrain of adult rats. Neuroscience 1998; 83:335-49. [PMID: 9460744 DOI: 10.1016/s0306-4522(97)00346-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In the immunohistochemical staining of nerve growth factor, it has been reported that fixation-dependent lability of nerve growth factor hampers its localization. In the present study, we used two different polyclonal antibodies to immunostain nerve growth factor in rat brain tissue. We found that in paraformaldehyde-fixed (immersion- or perfusion-fixed) brains, nerve growth factor-like immunoreactivity was located primarily in the cytoplasmic membrane and fiber tract of hippocampal neurons and was sparse in cortical neurons. When fresh frozen brain sections were fixed in paraformaldehyde solution, nerve-growth factor-like immunoreactivity was distributed evenly in the cell body. However, when fresh frozen brain sections were fixed in acetone, immunoreactivity to nerve growth factor was present as discrete or confluent dense particles in the cell body, especially in the nuclear region. Also, when paraformaldehyde-perfusion-fixed brain sections were heat treated in salt solution before immunostaining, nerve growth factor-like immunoreactivity could be retrieved in the cytoplasmic and nuclear regions. The hippocampal formation, cerebral cortex and basal forebrain expressed nerve growth factor-like immunoreactivity. Double immunostaining in fresh frozen brains showed that the low-affinity nerve growth factor receptor (p75) co-expressed with nerve growth factor and trkA proto-oncogene in basal forebrain neurons. Our study shows that formaldehyde fixation can mask nerve growth factor antigen, and special treatment, such as heating, is needed to retrieve nerve growth factor antigen to permit immunohistochemical detection. For immunohistochemical study of nerve growth factor in rat brain tissue, successful immunostaining can be obtained by using fresh frozen brains to prevent the masking effect of fixatives or by using paraformaldehyde-fixed brains with heat treatment. It is likely that nerve growth factor is synthesized and accumulated mainly in the cell body but not in the fiber tracts, which is similar to the distribution of its messenger RNA. The co-existence of p75 with nerve growth factor and trkA in basal forebrain neurons suggests the role of low- and high-affinity receptors in regulating the trophic effect of nerve growth factor.
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527
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Kim CK, Park SW, Kim PK, Cho M, Lee TH, Jun HK, Jang KL. Analysis of the envelope region of hepatitis G virus isolated from Korean patients. Mol Cells 1998; 8:117-23. [PMID: 9571642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The genetic diversity of hepatitis G virus (HGV) was investigated. By using a RT-PCR procedure, 14% of either HBV (hepatitis B virus)- or HCV (hepatitis C virus)-positive Korean hepatitis patients were proved to be HGV positives. Nucleotide sequences in the E1 region of the eight isolates from Korean patients and the six previously reported isolates were compared. Nucleotide substitutions spread uniformly throughout the E1 region. Sequence homology among the Korean isolates was 84-99% and 88-99% at the nucleotide and amino acid sequences, respectively, whereas those from different geographic areas was slightly lower at both levels. At least two genotypes might exist among the Korean HGV isolates. Compared to the corresponding region of HCV, the E1 sequence from HGV is moderately conserved. In addition, as frameshift mutations were observed in most of the Korean isolates compared to the prototype HGV sequence, the Korean isolates might not use the translational initiation site of the prototype HGV for polyprotein translation. Because a putative signal sequence of E1 for entry into endoplasmic reticulum starts from the N-terminus of the polyprotein, and capsid-like peptides composed of basic amino acids could not be detected from the upstream region of E1, the core protein of HGV is absent, or at least not present, at the region next to 5'-UTR. Therefore, HGV could be clearly distinguished from other genera of Flaviviridae.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Cloning, Molecular
- Flaviviridae/genetics
- Flaviviridae/isolation & purification
- Gene Products, env/chemistry
- Gene Products, env/genetics
- Gene Products, env/isolation & purification
- Genes, env
- Hepatitis, Viral, Human/genetics
- Hepatitis, Viral, Human/virology
- Humans
- Korea
- Molecular Sequence Data
- Polymerase Chain Reaction
- RNA, Viral/isolation & purification
- Sequence Analysis, RNA
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528
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Lee TH, Rhim TY, Son OK, Kim YH, Kim SS. Purification and characterization of lipopolysaccharide induced TNF-like factor from rabbit serum. Immunol Lett 1998; 60:97-102. [PMID: 9557950 DOI: 10.1016/s0165-2478(97)00134-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A TNF-like factor was purified from lipopolysaccharide (LPS) induced New Zealand white rabbit serum. The TNF-like factor was purified by DEAE-Sephacel, Sephacryl S-200, Mono-Q, CM-affi gel Blue, Superose 12 H/R preparative columns to the specific activity of 4 x 10(6) U/mg protein. The purified protein was 45 kDa in its oligomeric form and 22 kDa in its monomeric form. Rabbit TNF-like factor had a pI value of 5.0 and was resistant to trypsin digestion. The TNF-like factor reacted with polyclonal-Ab against human TNFalpha on immunoblot and immunoprecipitation analysis and interacted with human TNF receptors. Taken together, rabbit TNF-like factor might be a high molecular weight form of rabbit TNFalpha.
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529
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Fairchild DG, Hickey ML, Cook EF, McCarthy RM, Rossi LP, Timmons SC, Mangione CM, Lee TH. A prediction rule for the use of postdischarge medical services. J Gen Intern Med 1998; 13:98-105. [PMID: 9502369 PMCID: PMC1496911 DOI: 10.1046/j.1525-1497.1998.00025.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To develop and validate a prediction rule screening instrument, easily incorporated into the routine hospital admission assessment, that could facilitate discharge planning by identifying patients at the time of admission who are most likely to need postdischarge medical services. DESIGN Prospective cohort study with separate phases for prediction rule development and validation. SETTING Urban teaching hospital. PATIENTS/PARTICIPANTS General medical service patients, 381 in the derivation phase and 323 in the validation phase, who provided self-reported medical history, health status, and demographic data as a part of their admission nursing assessment, and were subsequently discharged alive. MEASUREMENTS AND MAIN RESULTS Use of postdischarge medical services such as visiting nurse or physical therapy, medical equipment, or placement in a rehabilitation or long-term care facility was determined. A prediction rule based on a patient's age and Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) physical function and social function scores stratified patients with regard to their risk of using postdischarge medical services. In the validation set, the rate of actual postdischarge medical service use was 15% (15 of 97), 36% (39 of 107), and 58% (57 of 98) among patients characterized by the prediction rule as being at "low", "intermediate," and "high" risk of using postdischarge medical services, respectively. CONCLUSIONS This prediction rule stratified general medical patients with regard to their likelihood of needing discharge planning to arrange for postdischarge medical services. Further research is necessary to determine whether prospective identification of patients likely to need discharge planning will make the hospital discharge planning process more efficient.
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530
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Chen CJ, Chen CM, Wu CL, Ro LS, Chen ST, Lee TH. Hirayama disease: MR diagnosis. AJNR Am J Neuroradiol 1998; 19:365-8. [PMID: 9504496 PMCID: PMC8338196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We report the MR findings in two cases of Hirayama disease, a kind of cervical myelopathy related to flexion movements of the neck. In flexion MR studies, we can see the striking and pathognomonic picture of anterior shifting of posterior dura at the lower cervical spinal canal. In nonflexion studies, we find that asymmetric cord atrophy, especially at the lower cervical cord, though subtle, is highly suggestive of Hirayama disease. When it is seen, a flexion MR study is warranted to prove this diagnosis.
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531
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Abstract
OBJECTIVES Rodenticide Vacor causes a severe peripheral neuropathy in humans. Electrophysiologic studies on a peripheral motor nerve-skeletal system of Vacor-treated rat showed decreased amplitude of muscle action potential without conduction velocity abnormalities. The ultrastructural studies of the neuromuscular junction were performed to clarify the anatomic site of the Vacor-induced peripheral neuropathy in male Wistar rats. METHODS After oral administration of a single dose of Vacor, 80 mg/kg of body weight, to the experimental animals, neuromuscular junctions within the interosseous muscles of the hind foot were observed in time. RESULTS No axon terminal change was noted until 24 hours after the administration of Vacor. Remarkable loss of presynaptic vesicles and swollen endoplasmic reticulum in the axon terminal were developed at 3 days after Vacor treatment. Progressive degenerative changes consisting of marked loss of presynaptic vesicles, focal disruption of membrane in the axon terminal with disappearance of the number of the damaged axon terminal appeared, and flattening of postsynaptic folds was also seen. CONCLUSIONS These results suggest that degenerative changes in axon terminal at neuromuscular junction may contribute to the peripheral neuropathy developed in the early phase of Vacor poisoning.
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532
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Abstract
This is the first report on microcystins from Microcystis aeruginosa Kützing in Taiwan. A total of nine strains of cyanobacteria have been isolated from eutrophic aquaculture ponds and water reservoirs. By mouse toxicity assay, six of the nine strains had LD100 in the range of 25-100 mg per kg mouse for dried bacterial mass. Microcystin-LR and -RR were found in all toxic strains and their contents ranged from 0.11-10.06 microg and 0.08 2.21 microg per mg of dried bacteria, respectively. Microcystin-RA, a minor component found only in M. TN-2 and M. CY-1 strains, was identified as a new microcystin. All three toxins were isolated by a serial separation on an LH-20 column, Si-flash column chromatography and reverse phase HPLC. Toxins were further identified by comparing their FABMS, 1H and 1H-1H COSY NMR spectra with the authentic microcystin-LR. Several other microcystin-like compounds were also found in the cultured strains and their structures are being determined.
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533
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Polanczyk CA, Johnson PA, Hartley LH, Walls RM, Shaykevich S, Lee TH. Clinical correlates and prognostic significance of early negative exercise tolerance test in patients with acute chest pain seen in the hospital emergency department. Am J Cardiol 1998; 81:288-92. [PMID: 9468069 DOI: 10.1016/s0002-9149(97)00897-7] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
An exercise tolerance test (ETT) is often performed to identify patients for early discharge after observation for acute chest pain, but the safety of this strategy is unproven. We prospectively studied 276 low-risk patients who underwent an ETT within 48 hours after presentation to the emergency department with acute chest pain. The ETT was considered negative if subjects achieved at least stage I of the Bruce protocol and the electrocardiogram showed no evidence of ischemia. There were no complications associated with ETT performance. The ETT was negative in 195 patients (71%); there was no identifiable subsets of patients at very low probability of an abnormal test. During the 6-month follow-up, patients with a negative ETT had fewer additional visits to the emergency department (17% vs 21%, respectively; p < 0.05) and fewer readmissions to the hospital (12% vs 17%; p < 0.01) than those with positive or inconclusive ETTs. No patient with a negative ETT died and only 4 patients with a negative ETT experienced a major cardiac event (myocardial infarction, coronary angioplasty, or bypass) within 6 months. Among these 4 patients, only 1 had an event within 4 months. In conclusion, our results suggest that ETT can be safely used to identify patients at low risk of subsequent events. Patients without a clearly negative test are at increased risk for readmission and cardiac events, and should be reevaluated either during the same admission or shortly after discharge.
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534
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Abstract
The hepatitis B virus X protein (HBx) is a broadly acting transactivator implicated in the development of liver cancer. Recently, HBx has been reported to interact with several different cellular proteins, including our report of its binding to XAP-1, the human homolog of the simian repair protein UVDDB. In the present study, several HBx mutants were used to localize the minimal domain of HBx required for binding to XAP-1/UVDDB to amino acids 55 to 101. The normal function of XAP-1/UVDDB is thought to involve binding to damaged DNA, the first step in nucleotide excision repair (NER); therefore, we hypothesized that this interaction may affect the cell's capacity to correct lesions in the genome. When tested in two independent assays that measure NER (unscheduled DNA synthesis and host cell reactivation), the expression of HBx significantly inhibited the ability of cells to repair damaged DNA. Under the assay conditions, HBx was expressed at a level similar to that previously observed during natural viral infection and was able to transactivate several target reporter genes. These results are consistent with a model in which HBx acts as a cofactor in hepatocarcinogenesis by preventing the cell from efficiently repairing damaged DNA, thus leading to an accumulation of DNA mutations and, eventually, cancer. An adverse effect on cellular DNA repair processes suggests a new mechanism by which a tumor-associated virus might contribute to carcinogenesis.
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535
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Lee TH. Cytokine networks in the pathogenesis of bronchial asthma: implications for therapy. JOURNAL OF THE ROYAL COLLEGE OF PHYSICIANS OF LONDON 1998; 32:56-64. [PMID: 9507443 PMCID: PMC9662974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Bronchial asthma is characterised by a multicellular inflammatory process in the airways. The bronchial inflammation is orchestrated by a network of cytokines and growth factors which includes those encoded by the GM-CSF/IL-4/IL-5 gene cluster on chromosome 5. Their cellular origins are diverse and include both inflammatory and structural cells in the airways. The efficacy of glucocorticoids in the therapy of bronchial asthma may include the ability to disrupt these cytokine networks. The failure of glucocorticoids to provide benefit in some asthmatic patients may be caused by an excess of pro-inflammatory transcription factors which sequester the glucocorticoid receptor (GR), thereby preventing it from exerting its anti-inflammatory effects. Progress is being made in the elucidation of the molecular regulation of the transcription of TH2 cytokine genes. These novel insights may provide future strategies for therapeutic intervention in asthma.
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536
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Hsieh HK, Lee TH, Wang JP, Wang JJ, Lin CN. Synthesis and anti-inflammatory effect of chalcones and related compounds. Pharm Res 1998; 15:39-46. [PMID: 9487544 DOI: 10.1023/a:1011940401754] [Citation(s) in RCA: 171] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE Mast cell and neutrophil degranulations are the important players in inflammatory disorders. Combined with potent inhibition of chemical mediators released from mast cells and neutrophil degranulations, it could be a promising anti-inflammatory agent. 2',5'-Dihydroxychalcone has been reported as a potent chemical mediator and cyclooxygenase inhibitor. In an effort to continually develop potent anti-inflammatory agents, a novel series of chalcone, 2'- and 3'-hydroxychalcones, 2',5'-dihydroxychalcones and flavanones were continually synthesized to evaluate their inhibitory effects on the activation of mast cells and neutrophils and the inhibitory effect on phlogist-induced hind-paw edema in mice. METHODS A series of chalcones and related compounds were prepared by Claisen-Schmidt condensation of appropriate acetophenones with appropriate aromatic aldehyde and the anti-inflammatory activities of these synthetic compounds were studied on inhibitory effects on the activation of mast cells and neutrophils. RESULTS Some chalcones showed strong inhibitory effects on the release of beta-glucuronidase and histamine from rat peritoneal mast cells stimulated with compound 48/80. Almost all chalcones and 4'-hydroxyflavanone exhibited potent inhibitory effects on the release of beta-glucuronidase and lysozyme from rat neutrophils stimulated with formyl-Met-Leu-Phe (fMLP). Some chalcones showed potent inhibitory effects on superoxide formation of rat neutrophils stimulated with fMLP/cytochalasin B (CB) or phorbol myristate acetate (PMA). 2',3-Dihydroxy-, 2',5'-dihydroxy-4-chloro-, and 2',5'-dihydroxychalcone showed remarkable inhibitory effects on hind-paw edema induced by polymyxin B in normal as well as in adrenalectomized mice. CONCLUSIONS These results indicated that the anti-inflammatory effects of these compounds were mediated, at least partly, through the suppression of chemical mediators released from mast cells and neutrophils.
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537
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Lee TH, Cooper HL. Translating good advice into better practice. JAMA 1997; 278:2108-9. [PMID: 9403428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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538
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Nichol G, Walls R, Goldman L, Pearson S, Hartley LH, Antman E, Stockman M, Teich JM, Cannon CP, Johnson PA, Kuntz KM, Lee TH. A critical pathway for management of patients with acute chest pain who are at low risk for myocardial ischemia: recommendations and potential impact. Ann Intern Med 1997; 127:996-1005. [PMID: 9412306 DOI: 10.7326/0003-4819-127-11-199712010-00009] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Use of resources for patients with acute chest pain may be improved with clinical strategies that integrate research, Bayesian analysis, and expert opinion. OBJECTIVES To 1) develop a critical pathway for management of patients with acute chest pain who are at low risk for complications of ischemic heart disease and 2) assess the potential effects of implementation of the pathway on patient safety and resource use. DESIGN Evidence-based consensus and prospective cohort study. SETTING Urban teaching hospital. PATIENTS Patients at least 30 years of age who were seen in the emergency department for chest pain and who did not have a history of trauma or abnormalities on radiologic study. INTERVENTION Physician-opinion leaders defined criteria for patient inclusion in the pathway and for remaining on the pathway after 6 or 12 hours of observation. Criteria were defined for appropriateness of direct admission, direct discharge, or 6 hours of observation followed by exercise treadmill testing. MEASUREMENTS Number of patients admitted to the hospital, number of days that patients were hospitalized, and clinical outcome. RESULTS 2898 of 4585 patients (63%) were admitted to the hospital; of the 2898, 1152 (40%) were classified as potentially eligible for the pathway and 1068 (93%) had a benign clinical course during the initial observation period. The 1068 patients had a mean length of stay of 2.8 +/- 4.8 days. If 47% of these patients had been discharged after observation and exercise testing, implementation of the pathway would have reduced the number of admissions by 505 (17%) and days of hospitalization by 1407 (11%). CONCLUSIONS Retrospective analysis suggests that a critical pathway for patients with acute chest pain may substantially reduce resource use. Prospective study is needed to ensure increased efficiency without increased adverse outcomes.
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539
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Fleischmann KE, Lee RT, Come PC, Goldman L, Kuntz KM, Johnson PA, Weissman MA, Lee TH. Clinical and echocardiographic correlates of health status in patients with acute chest pain. J Gen Intern Med 1997; 12:751-6. [PMID: 9436894 PMCID: PMC1497201 DOI: 10.1046/j.1525-1497.1997.07160.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To assess the ability of echocardiographic data to predict important functional status outcomes in patients with chest pain. DESIGN Prospective cohort study. SETTING A large, urban teaching hospital. PATIENTS Three hundred thirty-three patients admitted from the Emergency Department for evaluation of chest pain. MEASUREMENTS AND MAIN RESULTS Patients underwent two-dimensional and Doppler echocardiography as well as a face-to-face interview during their initial hospitalization and a telephone interview 1 year thereafter. The interview included the Medical Outcomes Study 36-Item Short Form (SF-36) health inventory, a generic health status instrument with a physical function subscale. The relation between clinical and echocardiographic factors and functional status was explored by univariable and multivariable linear regression and logistic regression analyses. Multiple clinical and echocardiographic factors correlated significantly with functional status measures at 1 year. For the SF-36 score at 1 year, age, male gender, white race, the presence of rales, and a comorbidity score were independently predictors in multivariate analysis; echocardiographic findings of severe left ventricular dysfunction (parameter estimate [PE] -27.6; 95% confidence interval [CI] -43.1, -12.2) and aortic insufficiency (PE -16.7; 95% CI -26.4, -7.0) added independent predictive information. Explanatory power (r2) for models using clinical and demographic variables was .27 and increased after inclusion of echocardiographic data to an r2 of .35. Results in the subset of patients (n = 148) with acute coronary syndromes such as unstable angina or myocardial infarction were qualitatively similar. Selected factors (rales on examination, electrocardiographic changes suggestive of ischemia, and moderate to severe mitral regurgitation) also predicted which patients would die or have a decline in their functional status. In multivariate analysis, only rales remained an independent predictor of poor outcome (odds ratio 2.4; 95% CI 1.2, 4.5). CONCLUSIONS Echocardiographic data are correlated with measures of functional status in patients with chest pain, but the ability to predict future functional status from clinical or echocardiographic information is limited. Because functional status cannot be predicted adequately from either patients' characteristics or echocardiographic testing, it must be assessed directly.
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540
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Fleischmann KE, Lee RT, Come PC, Goldman L, Cook EF, Weissman MA, Johnson PA, Lee TH. Impact of valvular regurgitation and ventricular dysfunction on long-term survival in patients with chest pain. Am J Cardiol 1997; 80:1266-72. [PMID: 9388096 DOI: 10.1016/s0002-9149(97)00663-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Doppler echocardiography is often used in evaluating patients with chest pain, but information on prognostic value of this testing and data to help guide selective use are limited. We prospectively studied 448 patients admitted from the emergency department for acute chest pain to assess the utility of qualitative echocardiographic data in predicting long-term survival and the incremental value of this information over routine clinical and electrocardiographic data. Doppler echocardiograms, recorded an average of 21 hours after presentation, were analyzed independently by 2 echocardiographers for global left and right ventricular function and valvular disease. Regional function was assessed by wall motion index. Data on long-term survival were collected with an average follow-up of 35.0 +/- 12.1 months. In univariate Cox regression analysis, left ventricular function and size, wall motion index, right ventricular function, and aortic, mitral, and tricuspid insufficiency were significant predictors of total and cardiovascular mortality. In multivariate analysis, moderate or severe left ventricular dysfunction (mortality rate ratio 3.2, 95% confidence intervals 1.8 to 5.8] and more than mild valvular regurgitation (mortality rate ratio 2.0, 95% confidence interval 1.1 to 3.6) were independent predictors of mortality in a model adjusted for clinical and electrocardiographic data. These factors were more common in patients aged >60 years, in those with prior acute myocardial infarction or angina, and in those with rales on physical examination. In the absence of these clinical characteristics, only 8 of 124 patients (7%) had moderate or severe left ventricular dysfunction or valvular regurgitation. In patients with moderate or severe regurgitation, a murmur was noted on the admission physical examination in 41 of 69 cases (59%). We conclude that echocardiographic evidence of moderate or severe left ventricular dysfunction or valvular regurgitation identifies a high-risk group for overall and cardiovascular mortality in patients with chest pain, and this evidence may not be detected clinically.
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541
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Sousa AR, Lams BE, Pfister R, Christie PE, Schmitz M, Lee TH. Expression of interleukin-5 and granulocyte-macrophage colony-stimulating factor in aspirin-sensitive and non-aspirin-sensitive asthmatic airways. Am J Respir Crit Care Med 1997; 156:1384-9. [PMID: 9372649 DOI: 10.1164/ajrccm.156.5.9702072] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Increased numbers of eosinophils and mast cells in the bronchial mucosa are characteristic features in subjects with aspirin-sensitive asthma. Interleukin-5 (IL-5) and granulocyte-macrophage colony-stimulating factor (GM-CSF) are involved in the activation, maturation, and perpetuation of survival of eosinophils. Immunohistochemical techniques were therefore used to study the expression of IL-5 and GM-CSF on frozen bronchial biopsies from 13 aspirin-sensitive asthmatic (ASA) and 8 non-ASA (NASA) subjects. Aspirin sensitivity was diagnosed by lysine-aspirin inhalation provocation. ASA airways demonstrated a significant 2-fold increase in the total number of submucosal inflammatory cells expressing IL-5 (p = 0.03) and approximate 4- and 2-fold increases in the numbers of mast cells expressing IL-5 and GM-CSF (p = 0.02 and p = 0.04, respectively). There was also a 4-fold increase in the number of eosinophils expressing IL-5 (p = 0.004). These results suggest a central role for the mast cell and eosinophil in regulation of the inflammatory cell infiltrate of ASA airways by secretion of the hemopoietic cytokines IL-5 and GM-CSF.
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542
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Sousa AR, Pfister R, Christie PE, Lane SJ, Nasser SM, Schmitz-Schumann M, Lee TH. Enhanced expression of cyclo-oxygenase isoenzyme 2 (COX-2) in asthmatic airways and its cellular distribution in aspirin-sensitive asthma. Thorax 1997; 52:940-5. [PMID: 9487340 PMCID: PMC1758450 DOI: 10.1136/thx.52.11.940] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND There are two isoforms of cyclo-oxygenase (COX), namely COX-1 and COX-2. COX-1 is constitutively expressed in most tissues and in blood platelets. The metabolites derived from COX-1 are probably involved in cellular housekeeping functions. COX-2 is expressed only following cellular activation by inflammatory stimuli and is thought to be involved in inflammation. METHODS The expression of COX-1 and COX-2 isoenzymes has been studied in the bronchial mucosa of 10 normal and 18 asthmatic subjects, 11 of whom had aspirin-sensitive asthma (ASA) and seven had non-aspirin-sensitive asthma (NASA) RESULTS: There was a significant fourfold and 14-fold increase, respectively, in the epithelial and submucosal cellular expression of COX-2, but not of COX-1, in asthmatic patients. There was no significant difference in the total number of cells staining for either COX-1 or COX-2 between subjects with ASA and NASA, but the number and percentage of mast cells that expressed COX-2 was significantly increased sixfold and twofold, respectively, in individuals with ASA. There was a mean fourfold increase in the percentage of COX-2 expressing cells that were mast cells in subjects with ASA and the number of eosinophils expressing COX-2 was increased 2.5-fold in these subjects. CONCLUSION COX-2-derived metabolites may play an essential part in the inflammatory processes present in asthmatic airways and development of drugs targeted at this isoenzyme may have therapeutic potential in the treatment of asthma. Mast cells and eosinophils may also have a central role in the pathology of aspirin-sensitive asthma.
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543
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Mangione CM, Goldman L, Orav EJ, Marcantonio ER, Pedan A, Ludwig LE, Donaldson MC, Sugarbaker DJ, Poss R, Lee TH. Health-related quality of life after elective surgery: measurement of longitudinal changes. J Gen Intern Med 1997; 12:686-97. [PMID: 9383137 PMCID: PMC1497188 DOI: 10.1046/j.1525-1497.1997.07142.x] [Citation(s) in RCA: 145] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To examine the responsiveness of the 36-Item Short Form Health Survey (SF-36) to clinical changes in three surgical groups and to study how health-related quality of life (HRQL) changes with time among patients who undergo total hip arthroplasty, thoracic surgery for treatment of non-small-cell lung cancer, or abdominal aortic aneurysm (AAA) repair. DESIGN Prospective cohort study with serial evaluations of HRQL preoperatively and at 1, 6, and 12 months after surgery. SETTING University tertiary care hospital. PATIENTS Of 528 patients, more than 50 years of age, who were admitted for these elective procedures, 454 (86%) provided preoperative health status data and are members of the study cohort. At 12 months after surgery, 439 (93%) of the cohort was successfully contacted and 390 (90%) provided follow-up interviews. MEASUREMENTS AND MAIN RESULTS The Medical Outcomes Study SF-36, the Specific Activity Scale, five validated health transition questions, and a 0 to 100 scale measure of global health were used to assess changes in health status at 1, 6, and 12 months after surgery. Change in health status as measured by the SF-36 demonstrated that physical function and role limitations due to physical health problems were worse 1 month after these three surgeries. However, by 6 months after surgery, most patients experienced significant gains in the majority of the dimensions of health, and these gains were sustained at 12 months after surgery. Longitudinal changes in the SF-36 were positively associated with responses to the five health transition questions, to changes on the Specific Activity Scale and global health rating question, and to clinical parameters for persons who had AAA repair. These findings indicate that the SF-36 has evidence of validity and is responsive to expected changes in HRQL after elective surgery for these procedures. CONCLUSIONS For the total hip arthroplasty patients, responsiveness was greatest for the SF-36 scales that measure physical constructs. However, for the two other procedures and at various points of recovery, significant changes were observed for all eight subscales, suggesting that responsiveness was dependent on the type of surgery and the timing of follow-up, and that multidimensional measures are needed to fully capture changes in HRQL after surgery.
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544
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Kim CH, Oh Y, Lee TH. Codon optimization for high-level expression of human erythropoietin (EPO) in mammalian cells. Gene 1997; 199:293-301. [PMID: 9358069 DOI: 10.1016/s0378-1119(97)00384-3] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Codon bias has been observed in many species. The usage of selective codons in a given gene is positively correlated with its expression efficiency. As an experimental approach to study codon-usage effects on heterologous gene expression in mammalian cells, we designed two human erythropoietin (EPO) genes, one in which native codons were systematically substituted with codons frequently found in highly expressed human genes and the other with codons prevalent in yeast genes. Relative performances of the re-engineered EPO genes were evaluated with various combinations of promoters and signal leader sequences. Under the comparable set of combinations, mature EPO gene with human high-frequency codons gave a considerably higher level of expression than that with yeast high-frequency codons. However, the levels of EPO expression varied, depending on the alternate combinations. Since the promoters and the signal leader sequences that we used are known to be equally efficient in gene expression, we hypothesized that the varied expression levels were due to the linear sequence between the promoter and the coding gene sequence. To test this possibility, we designed the EPO gene with hybrid codon usage in which the 5'-proximal region of the EPO gene was synthesized with yeast-biased codons and the rest with human-biased codons. This codon-usage hybrid EPO gene substantially enhanced the level of EPO transcripts and proteins up to 2.9-fold and 13.8-fold, respectively, when compared to the level reached by the original counterpart. Our results suggest that the linear sequence between the promoter and the 5'-proximal region of a gene plays an important role in achieving high-level expression in mammalian cells.
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545
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Lee TH, Shimazaki K, Yu SL, Nam MS, Kim SJ, Lee KK, Yu DY. Polymorphic sequence of Korean Native goat lactoferrin exhibiting greater antibacterial activity. Anim Genet 1997; 28:367-9. [PMID: 9363601 DOI: 10.1111/j.1365-2052.1997.00154.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Lactoferrin, which exhibits antibacterial activity to protect infants from infectious disease, is a major component of colostrum and milk. Lactoferrin was purified from the colostrum of Korean Native goat, and the cDNA from the mammary gland mRNA of the animal was cloned and sequenced. The nucleotide sequence of the lactoferrin gene of Korean Native goat was found to differ in 15 sites from that of the goat lactoferrin gene reported earlier. This difference in nucleotide sequence resulted in six amino acid substitutions: five in the N-lobe and one in the C-lobe. The antibacterial activity of Korean Native goat lactoferrin was found to be greater than that of Sannen goat lactoferrin.
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546
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Hwang JS, Song KS, Kim WG, Lee TH, Koshino H, Yoo ID. Polyozellin, a new inhibitor of prolyl endopeptidase from Polyozellus multiplex. J Antibiot (Tokyo) 1997; 50:773-7. [PMID: 9360624 DOI: 10.7164/antibiotics.50.773] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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547
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Caulfield JJ, Hawrylowicz CM, Kemeny DM, Lee TH. GM-CSF increases the ability of cultured macrophages to support autologous CD4+ T-cell proliferation in response to Dermatophagoides pteronyssinus and PPD antigen. Immunol Suppl 1997; 92:123-30. [PMID: 9370934 PMCID: PMC1363991 DOI: 10.1046/j.1365-2567.1997.00320.x] [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: 02/05/2023]
Abstract
Previous studies have demonstrated an infiltration of monocytes and increased levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) in the asthmatic lung. To study the possible effects of this cytokine upon the differentiation and function of these newly recruited monocytes, we have developed a model in which monocytes isolated from human peripheral blood were differentiated into macrophages in serum in the presence or absence of GM-CSF. After 7 days, the macrophages increased in size and granularity, had increased phagocytic activity, and expressed various adhesion molecules, CD14 and major histocompatibility complex (MHC) class II. The effects of GM-CSF on antigen presentation by cultured macrophages on the antigen-specific proliferative response of CD4+ T cells to Dermatophagoides pteronyssinus or purified protein derivative of tuberculin and the mitogen phytohaemagglutinin was determined. CD4+ T-cell proliferation was reduced when either antigen was presented by macrophages cultured in serum alone, compared with the values obtained with freshly isolated monocytes. However, CD4+ cell proliferation was comparable to that observed with monocytes when antigen was presented by macrophages which had been pre-cultured with 50 U/ml GM-CSF. CD4+ T-cell proliferation to phytohaemagglutinin was similar when all three populations were used as accessory cells. High numbers of macrophages partially suppressed CD4+ T-cell proliferation in response to antigen presented by monocytes, but there was no significant difference between macrophages cultured in the presence or absence of GM-CSF. This data suggests that GM-CSF directs monocyte differentiation into macrophages with an antigen-presenting, rather than a suppressive, phenotype. Elevated levels of GM-CSF in the asthmatic lung may therefore maintain recently recruited monocytes in an inflammatory and T-cell activating state.
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548
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Lee TH, Chun GT, Chang YK. Development of sporulation/immobilization method and its application for the continuous production of cyclosporin A by Tolypocladium inflatum. Biotechnol Prog 1997; 13:546-50. [PMID: 9376111 DOI: 10.1021/bp970069j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
An efficient sporulation/immobilization procedure for immobilized fungal cell culture was developed by modifying an existing immobilized technique to shorten the time and number of steps for sporulation. This method was applied to an immobilized-cell perfusion bioprocess (IPB) for continuous production of CyA, an intracellular secondary metabolite produced by a filamentous fungus, Tolypocladium inflatum. In the IPB, the fungal cells were immobilized in the pores of celite beads (100-500 microm) and a top-driven stirred tank fermentor was used for the culture. The IPB showed good process benefits as demonstrated by the high density of immobilized cells continuously producing CyA-containing free cells. The productivity of cyA-containing free cells in the effluent was very high, ca. 1.0g/(L/h) at a dilution rate of 0.1 h-1, due to the high density of immobilized cells in the fermentor. The CyA productivity was 4.0-6.0 mg/(L/h) which was about 6-10-fold higher than that of batch suspended cell culture. Such an efficient IPB was possible since a decantor was developed in this study, which could effectively separate cell-immobilized beads from the effluent although bead loss slightly increased as the cell loading increased in the latter part of culture. Furthermore, long-term operation of IPB was carried out successfully by employing an in-situ immobilization strategy. It was found that a large number of spores in the fermentation broth in the reactor were entrapped in-situ into the newly supplemented celite beads and then germinated, thus forming new immobilized cells.
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549
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Carrier E, Lee TH, Busch MP, Cowan MJ. Recruitment of engrafted donor cells postnatally into the blood with cytokines after in utero transplantation in mice. Transplantation 1997; 64:627-33. [PMID: 9293877 DOI: 10.1097/00007890-199708270-00014] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND We have previously shown that MHC-mismatched fetal liver cells can durably engraft in 45% of nondefective fetal mice, although male donor cells were found in the blood in only 8% of female recipients. We postulated that adult bone marrow stem cells would engraft similarly to fetal liver cells and that postnatal administration of cytokines would recruit donor cells into the peripheral circulation. METHODS Bone marrow from C57BL/6 adult male mice was injected into allogeneic BALB/c or congenic C57BL/6 fetal recipients that were 11-13 days old. Engraftment was tested by quantitative polymerase chain reaction for the Y chromosome in female recipients (0.0001% sensitivity). Recipients were injected at 1-2 years of age with rat stem cell factor (SCF) and human granulocyte colony-stimulating factor (G-CSF) for 7 days and tested for donor cells in the blood. RESULTS The overall engraftment rate (in the blood, spleen, or liver) was 44% in both female allogeneic and congenic bone marrow recipients. Of 49 recipients of bone marrow or fetal liver cells with no evidence of donor cells in the blood before injection, 29 (59%) developed circulating donor cells at some time after cytokine injection for up to 2 months. Twenty-seven of 49 animals were negative in the blood, liver, and spleen before cytokine therapy; 14 of 27 (52%) became positive in the blood after stem cell factor/granulocyte colony-stimulating factor injection. Tolerance to donor skin grafts was not altered by the mobilization of donor cells into the circulation. CONCLUSIONS Adult bone marrow durably engrafts in nondefective mice at a rate similar to that previously obtained with fetal liver. Engrafted donor cells can be mobilized with cytokines into the circulation for up to 2 months even in animals with no evidence of donor cells in the blood, liver, or spleen. Based on these results we estimate that 70-75% of hematopoietically nondefective fetal mice engraft with MHC-mismatched fetal liver or adult bone marrow stem cells.
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550
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Maisel WH, Kuntz KM, Reimold SC, Lee TH, Antman EM, Friedman PL, Stevenson WG. Risk of initiating antiarrhythmic drug therapy for atrial fibrillation in patients admitted to a university hospital. Ann Intern Med 1997; 127:281-4. [PMID: 9265427 DOI: 10.7326/0003-4819-127-4-199708150-00004] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND The risks of antiarrhythmic therapy are increasingly recognized, but the risks associated with the initiation of antiarrhythmic therapy in patients hospitalized for atrial fibrillation are poorly defined. OBJECTIVE To determine the incidence, time course, and predictors of adverse cardiac events that require intervention during initiation of antiarrhythmic drug therapy for atrial fibrillation. DESIGN Retrospective chart review. SETTING University hospital. PARTICIPANTS 417 consecutive patients who underwent a total of 597 drug trials during a total of 550 hospitalizations for atrial fibrillation. INTERVENTION Initiation of therapy with antiarrhythmic drugs: procainamide (189 trials), quinidine (179 trials), disopyramide (20 trials), propafenone (110 trials), flecainide (2 trials), sotalol (72 trials), and amiodarone (25 trials). Electrical conversion was performed during 247 trials. MEASUREMENTS Incidence of adverse events and daily hazard rate were measured. Logistic regression was done to identify risk factors. RESULTS During the 597 drug trials, 80 (13.4%) cardiac adverse events occurred in 73 patients. The risk was greatest during the first 24 hours of therapy. Bradyarrhythmias were the most common adverse event, occurring in 47 trials (7.9%); prolongation of the QT interval warranting discontinuation of drug therapy (9 trials; 1.5%) and ventricular arrhythmias (8 trials; 1.3%) were less frequent. In multivariate analysis, previous myocardial infarction was associated with increased risk (odds ratio, 1.90 [95% CI, 1.05 to 3.43]) and the association between older age and increased risk (odds ratio, 1.29 per decade [CI, 0.97 to 1.72]) was of borderline statistical significance. CONCLUSIONS A significant risk for cardiac adverse events exists during initiation of antiarrhythmic therapy in patients hospitalized for atrial fibrillation. Observation with electrocardiographic monitoring seems advisable for 24 to 48 hours during initiation of antiarrhythmic therapy, particularly for elderly patients and patients who have previously had myocardial infarction.
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