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Lee TK, Chan KW, Huang ZS, Ng SK, Lin RT, Po HL, Yuan RY, Lai ML, Chang TW, Yan SH, Deng JC, Liu LH, Lee KY, Lie SK, Sung SM, Hu HH. Effectiveness of low-dose ASA in prevention of secondary ischemic stroke, the ASA Study Group in Taiwan. Thromb Res 1997; 87:215-24. [PMID: 9259112 DOI: 10.1016/s0049-3848(97)00121-7] [Citation(s) in RCA: 11] [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
This randomized double-blind controlled study was carried out to investigate the effect of 100 mg acetylsalicylic acid (ASA) per day on the secondary prevention of ischemic stroke. Patients who suffered a first ischemic stroke from 13 participating hospitals were enrolled. They were independent or only partially dependent in activities of daily living and all had received brain CT for diagnosis. Eligible patients were randomly allocated to the 100 mg ASA or the nicametate citrate (a vasodilator) groups, and trial medications were started within three to six weeks after the onset of stroke. The primary end point was cerebral reinfarction, and intracranial hemorrhage was classified as an adverse event. Four hundred and sixty-six patients participated in this study; and 222 cases (136 males and 86 females) were allocated to the ASA group while 244 cases (150 males and 94 females) were assigned to the nicametate group. No significant difference in baseline characteristics between the two groups was observed. Cerebral reinfarction developed 6.3% (14/222) in the ASA group and 11.9% (29/244) in the nicametate group. According to the Cox's proportional hazards model, the estimated risk ratio (ASA group vs. nicametate group) was 0.538, with a 95% confidence interval of 0.284-1.019. The result was of borderline statistical significance. The risk for cerebral reinfarction was reduced by almost 50% among those who took 100 mg ASA versus those who took nicametate.
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Cole KD, Lee TK, Lubon H. Aqueous two-phase partitioning of milk proteins. Application to human protein C secreted in pig milk. Appl Biochem Biotechnol 1997; 67:97-112. [PMID: 9382491 DOI: 10.1007/bf02787845] [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: 02/05/2023]
Abstract
Milk of transgenic pigs secreting recombinant human Protein C (rHPC) was used as a model system to determine the utility of aqueous two-phase extraction systems (ATPS) for the initial step in the purification of proteins from milk. The major challenges in purification of recombinant proteins from milk are removal of casein micelles (that foul processing equipment) and elimination of the host milk proteins from the final product. When milk was partitioned in ATPS composed of polyethylene glycol (PEG) and ammonium sulfate (AS), the phases were clarified and most of the caseins precipitated at the interphase. The partition coefficients of the major milk proteins and rHPC were dependent upon the molecular weight of the PEG used in the ATPS. Higher-partition coefficients of the major whey proteins, beta-lactoglobulin, and alpha-lactalbumin were observed in ATPS made up of lower molecular-weight PEG (1000 or 1450) as compared to systems using higher molecular-weight PEG. Lowering the pH of the ATPS from 7.5 to 6.0 resulted in increased precipitation of the caseins and decreased their concentration in both phases. rHPC had a partition coefficient of 0.04 in a system composed of AS and PEG 1450. The rHPC in pig milk was shown to be highly heterogenous by two-dimensional gel electrophoresis. The heterogeneity was owing to inefficient proteolytic processing of the single chain to the heterodimeric form and differences in glycosylation and other post-translational processing. Differential partitioning of the multiple forms of purified rHPC in the ATPS was not observed. rHPC after processing in ATPS was recovered in a clear phase free of most major milk proteins. ATPS are useful as the initial processing step in the purification of recombinant proteins from milk because clarification and enrichment in combined in a single step.
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Abstract
We have previously described the expression of the human proprotein convertase furin or paired basic amino acid-cleaving enzyme, in mice transgenic for paired basic amino acid-cleaving enzyme and human Protein C (HPC). Here we show 100-fold or higher expression of furin in the mammary gland, compared with endogenous furin. Furin and recombinant HPC were detected in the same regions of the mammary gland and regulated similar to the endogenous whey acidic protein. In addition to the expected intracellular localization, furin was secreted into the milk as an 80-kDa form lacking the transmembrane and cytoplasmic domains. Furin present at levels of up to 40,000 units/ml milk cleaved the t-butoxycarbonyl-RVRR-AMC substrate with a Km of 32 microM, and processed the recombinant HPC precursor at the appropriate sites. Surprisingly, the expression of an active protease was not toxic to the mammary gland. This is a rare example of an animal model secreting active truncated forms of a processing endoprotease into a bodily fluid.
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Lee TK, O'Brien KF, Wiley AL, Means JA, Karlsson UL. Reliability of finger stick capillary blood for the lymphocyte micronucleus assay. Mutagenesis 1997; 12:79-81. [PMID: 9106247 DOI: 10.1093/mutage/12.2.79] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Compared with peripheral blood sampling, capillary blood collecting by finger stick is less traumatic and more convenient. To assess the sensitivity and reliability of capillary blood for the lymphocyte micronucleus (MN) assay, this study was performed in three sample groups, i.e. healthy donors (n = 3), cancer patients before treatment (n = 7), and cancer patients who were undergoing fractionated partial-body radiotherapy (n = 9). For each group, we measured three intra-individual variables, i.e. micronucleus (MN) frequency, binucleate (BN) index, and micronucleated BN index of lymphocytes obtained from capillary blood and the corresponding peripheral blood. Our results indicated that in all three sample groups, the differences in these variables between capillary blood and peripheral blood either before or after ex vivo 137Cs irradiation (2 Gy) were insignificant. Since capillary blood is more accessible than peripheral blood, we believe that it is a reliable source for the lymphocyte MN assay especially when venipuncture is not convenient.
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Kim CH, Lee TK. Characterization of a monoclonal antibody that specifically inhibits pullulanase activity of Bacillus circulans amylase-pullulanase enzyme. Appl Biochem Biotechnol 1997; 62:191-200. [PMID: 9170253 DOI: 10.1007/bf02787995] [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: 02/04/2023]
Abstract
A monoclonal antibody (MAb) against amylase pullulanase enzyme from Bacillus circulans, which hydrolyzes not only the alpha-1,6-glycosidic linkage but also the alpha-1,4-glycosidic linkage to the same extent, has been produced by the fusion of BALB/c mouse spleen cells immunized with the native enzyme and P3x63Ag8U1 myeloma cells, and examined for inhibition of pullulanase activity in order to characterize the catalytic site of the pullulanase. The MAb recognizes active enzyme, but not the SDS-denatured or heat-inactivated protein, indicating that the antibody is highly conformational-dependent, specific for active enzyme. The antibody inhibited the pullulanase activity, but not amylase activity. The monoclonal antibody immunoblotted the enzyme and immunoprecipitated the enzyme. The immunoprecipitation was inhibited in the presence of substrate, pullulan, and the MAb competitively inhibited the binding of pullulan to the enzyme. The MAb, therefore, recognizes the pullulan-binding site of the enzyme. Kinetic analysis showed that the MAb inhibited pullulanase activity with inhibition constant (Ki) of 0.77 microgram/mL, providing evidence that the antibody decreases the catalytic rate of enzyme activity and has an effect on substrate binding. These results strongly confirm the previous observations that APE may have two different active sites responsible for the expression of amylase and pullulanase activities (Kim, C.H. and Kim, Y.S. Eur. J. Biochem. 1995, 227, 687-693).
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Li L, Lee TK, Ballatori N. Functional re-evaluation of the putative glutathione transporters, RcGshT and RsGshT. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 1997; 70:301-10. [PMID: 9626750 PMCID: PMC2589333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Transport systems that mediate glutathione (GSH) efflux from hepatocytes into blood plasma and bile have been characterized extensively in sinusoidal and canalicular membrane vesicles, and recent reports describe two candidate GSH transport proteins: the rat sinusoidal GSH transporter (RsGshT) and rat canalicular GSH transporter (RcGshT). However, studies in our laboratory have been unable to confirm the function of these gene products. Xenopus laevis oocytes injected with either rat liver mRNA, the cRNA for RcGshT or the cRNA for RsGshT did not transport GSH at a higher rate than water-injected oocytes, when measured either as 3H-GSH uptake or efflux, at low or high GSH concentrations, or in the presence or absence of acivicin to inhibit gamma-glutamyltransferase activity. In contrast, transport of 3H-taurocholate was markedly accelerated in oocytes injected with rat liver mRNA or the cRNA for the Na(+)-taurocholate cotransporting polypeptide (Ntcp), confirming the integrity of the mRNA and the viability of the oocytes. Northern blot analysis failed to detect an RcGshT transcript in rat liver total RNA or rat liver mRNA. Of significance, the RcGshT and RsGshT cDNA sequences are similar to those found in the Escherichia coli K-12 genome, indicating possible cloning artifacts. Further studies are needed to resolve this discrepancy, and to isolate and characterize hepatic GSH transport proteins.
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Lee TK, Li L, Ballatori N. Hepatic glutathione and glutathione S-conjugate transport mechanisms. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 1997; 70:287-300. [PMID: 9626749 PMCID: PMC2589341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Glutathione (GSH) plays a critical role in many cellular processes, including the metabolism and detoxification of oxidants, metals, and other reactive electrophilic compounds of both endogenous and exogenous origin. Because the liver is a major site of GSH and glutathione S-conjugate biosynthesis and export, significant effort has been devoted to characterizing liver cell sinusoidal and canalicular membrane transporters for these compounds. Glutathione S-conjugates synthesized in the liver are secreted preferentially into bile, and recent studies in isolated canalicular membrane vesicles indicate that there are multiple transport mechanisms for these conjugates, including those that are energized by ATP hydrolysis and those that may be driven by the electrochemical gradient. Glutathione S-conjugates that are relatively hydrophobic or have a bulky S-substituent are good substrates for the canalicular ATP-dependent transporter mrp2 (multidrug resistance-associated protein 2, also called cMOAT, the canalicular multispecific organic anion transporter, or cMrp, the canalicular isoform of mrp). In contrast with the glutathione S-conjugates, hepatic GSH is released into both blood and bile. GSH transport across both of these membrane domains is of low affinity and is energized by the electrochemical potential. Recent reports describe two candidate GSH transport proteins for the canalicular and sinusoidal membranes (RcGshT and RsGshT, respectively); however, some concerns have been raised regarding these studies. Additional work is needed to characterize GSH transporters at the functional and molecular level.
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Chen YC, Lee TK. Variational study of the spin-gap phase of the one-dimensional t-J model. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:9062-9065. [PMID: 9984633 DOI: 10.1103/physrevb.54.9062] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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109
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Lee CW, Park SJ, Park SW, Kim JJ, Hong MK, Lee SJ, Lee TK, Lee JH, Lim TH. 31P nuclear magnetic resonance evidence of skeletal muscle metabolic abnormalities in mitral stenosis. Am J Cardiol 1996; 78:588-91. [PMID: 8806352 DOI: 10.1016/s0002-9149(96)00373-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We used in vivo 31P nuclear magnetic resonance spectroscopy to follow phosphorylated metabolites of dominant forearm flexor muscles during exercise in patients with mitral stenosis. The results showed that skeletal muscle metabolism during exercise is abnormal.
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110
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Lee TK, Egbert TP, Westenskow DR. Supraorbital artery as an alternative site for oscillometric blood pressure measurement. J Clin Monit Comput 1996; 12:293-7. [PMID: 8863108 DOI: 10.1007/bf02221749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Noninvasive blood pressure measured from the superficial temporal artery has been shown to correlate well with pressure in the brachial artery. The supraorbital artery may be an even better site for monitoring blood pressure on the forehead because it originates from the internal carotid artery, and it is easier to locate anatomically. This study compares mean pressure measured oscillometrically over the supraorbital artery and at the upper arm. METHODS Oscillometric signals from the supraorbital artery were recorded in 20 surgical patients under general anesthesia using a 2.5- x 1-cm bladder attached to the forehead with a self-adhesive pad. Blood pressure was measured simultaneously from the arm using a Dinamap 1846 blood pressure monitor, and the resulting data compared with the supraorbital artery measurements. RESULTS The mean difference between 219 pairs of blood pressure measurements, from the forehead and the arm, was 3.8 mm Hg. The standard deviation of the differences was 7.4 mm Hg. The linear regression equation for the data was y = 0.98x + 3.25, with a standard error of estimate of 7.31 mm Hg. The correlation coefficient between the two measurements was 0.82. CONCLUSIONS The results show that mean blood pressures measured oscillometrically from the supraorbital and brachial arteries agree and correlate well with each other. The supraorbital artery should be a good alternative site for blood pressure measurement.
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111
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Chia YW, Lee TK, Kour NW, Tung KH, Tan ES. Microchip implants on the anterior sacral roots in patients with spinal trauma: does it improve bowel function? Dis Colon Rectum 1996; 39:690-4. [PMID: 8646959 DOI: 10.1007/bf02056952] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE This study evaluated the effect of anterior sacral roots stimulator implants on bowel function of patients with spinal cord trauma. METHOD Eight patients with spinal cord injury and constipation had anterior sacral roots stimulator implants inserted for concomitant bladder dysfunction. Questionnaires on bowel function and anorectal manometry tests were given before and after insertion of the implants. RESULTS Six patients achieved improvement in bowel function. Four of these patients could defecate spontaneously following stimulation. Two patients had no improvement in bowel function. Anorectal manometry studies showed a negative rectoanal pressure difference at the time of stimulation. All patients were unable to defecate during stimulation. Positive rectoanal pressure difference was recorded in the six patients who had improved bowel function. This may be attributable to the slower relaxation of the smooth rectal muscle compared with the easily fatigable striated external anal sphincter. CONCLUSION Anterior sacral roots stimulator implants can improve bowel function in patients with spinal cord trauma.
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Abstract
We have produced recombinant human Protein C (rHPC) in the milk of transgenic swine. After purification, we have analyzed the interaction of teh zymogen with Protac, thrombin/thrombomodulin and thrombin alone. The amidolytic and anticoagulant activities of rAPC after Protac activation were approximately 80% those of its human plasma counterpart. Upon the excision of the activation peptide by thrombin/thrombomodulin complex, both the natural and recombinant activation products had similar enzymatic and biological activities. This observation can be attributed to the difference in the mechanism of action between the two activators and structural differences between HPC and rHPC.
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113
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Lee TK, Wiley AL, Esinhart JD. Correlation of 137Cs-induced micronuclei with survival fraction in human HT29 cancer cells. Chin Med J (Engl) 1996; 109:247-8. [PMID: 8758319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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Huang ZS, Wang CH, Yip PK, Yang CY, Lee TK. In hypercholesterolemia, lower peripheral monocyte count is unique among the major predictors of atherosclerosis. Arterioscler Thromb Vasc Biol 1996; 16:256-61. [PMID: 8620340 DOI: 10.1161/01.atv.16.2.256] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Many studies have shown that enhanced monocyte adherence is an important factor in the initiation of atherosclerosis. Because the relationships between circulating monocyte count and atherosclerosis or its major predictors have received little attention, we conducted this study with the aim of clarifying these relationships. The study included 409 men and women who underwent a carotid artery duplex study and white blood cell analysis (Sysmex Cell Counter) during a 2-day health check at our hospital in 1994. We found no correlation between preexisting carotid atherosclerosis and monocyte count. After adjustment for age and sex, hypercholesterolemia, among the major predictors of atherosclerosis, showed a unique correlation with both lower monocyte count and percentage (P < .001, P < .0001, respectively), whereas smoking was correlated with a higher monocyte count (P < .001). There was a slight but nonsignificant increase in monocyte count in hypertension, diabetes, and hypertriglyceridemia. Our results imply that: (1) hypercholesterolemia has a strong, peripheral monocyte-reducing effect, probably due to direct enhancement of monocyte adhesion to the endothelium, which subsequently initiates the atherosclerotic process, and (2) the mechanisms of other predictor(s)-induced atherosclerosis may be quite different from that of hypercholesterolemia. Another possible explanation for the inverse correlation between monocyte count and serum cholesterol level is that decreased monocyte levels might lead to hypercholesterolemia because of decreased uptake of cholesterol from the plasma by less monocyte-derived macrophages. The reasons why preexisting carotid atherosclerosis did not correlate with monocyte count are also discussed.
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Lee TK, Haynes RJ, Longo JA, Chu JR. Pin removal in slipped capital femoral epiphysis: the unsuitability of titanium devices. J Pediatr Orthop 1996; 16:49-52. [PMID: 8747353 DOI: 10.1097/00004694-199601000-00009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In an effort to predict which slipped capital femoral epiphysis fixation devices might cause fewer retrieval problems, 27 consecutive implant-retrieval procedures were reviewed, and mechanical tests using many currently available devices were performed. Problems occurred with both stainless steel and titanium devices if implanted for > 1 year. This tendency for increased problems was statistically significant for the titanium group, and analysis of a retrieved titanium screw showed evidence of osseointegration (direct bone-metal contact at > 90% of the interface) using backscattered image scanning electron microscopic analysis. These clinical data and data from mechanical testing suggest that stainless steel screws or trocar-tipped Steinmann pins are better suited for fixation of slipped capital femoral epiphysis.
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Abstract
Hospitals and other health care providers are being squeezed by declining reimbursement and capitated revenues. As this happens they are looking to expand into rapidly developing and newly industrialised countries. This article will focus on the People's Republic of China as a country with opportunities for developing private hospitals and health care facilities.
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Drews R, Paleyanda RK, Lee TK, Chang RR, Rehemtulla A, Kaufman RJ, Drohan WN, Luboń H. Proteolytic maturation of protein C upon engineering the mouse mammary gland to express furin. Proc Natl Acad Sci U S A 1995; 92:10462-6. [PMID: 7479820 PMCID: PMC40631 DOI: 10.1073/pnas.92.23.10462] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Endoproteolytic processing of the human protein C (HPC) precursor to its mature form involves cleavage of the propeptide after amino acids Lys-2-Arg-1 and removal of a Lys156-Arg157 dipeptide connecting the light and heavy chains. This processing was inefficient in the mammary gland of transgenic mice and pigs. We hypothesized that the protein processing capacity of specific animal organs may be improved by the coexpression of selected processing enzymes. We tested this by targeting expression of the human proprotein processing enzyme, named paired basic amino acid cleaving enzyme (PACE)/furin, or an enzymatically inactive mutant, PACEM, to the mouse mammary gland. In contrast to mice expressing HPC alone, or to HPC/PACEM bigenic mice, coexpression of PACE with HPC resulted in efficient conversion of the precursor to mature protein, with cleavage at the appropriate sites. These results suggest the involvement of PACE in the processing of HPC in vivo and represent an example of the engineering of animal organs into bioreactors with enhanced protein processing capacity.
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Narus S, Egbert T, Lee TK, Lu J, Westenskow D. Noninvasive blood pressure monitoring from the supraorbital artery using an artificial neural network oscillometric algorithm. J Clin Monit Comput 1995; 11:289-97. [PMID: 7595684 DOI: 10.1007/bf01616986] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE Our objective was to overcome the limitations of linear models of oscillometric blood pressure determination by using a nonlinear technique to model the relationship between the oscillometric envelope and systolic and diastolic blood pressures, and then to use that technique for near-continuous arterial pressure monitoring at the supraorbital artery. METHODS An adhesive pressure pad and transducer were used to collect oscillometric data from the supraorbital artery of 85 subjects. These data were then used to train an artificial neural network (ANN) to report diastolic or systolic pressure. Arterial pressure measurements defined by brachial artery auscultation were used as a reference. ANN results were compared with those obtained using a standard oscillometric algorithm that determined pressures based on fixed percentages of the maximum oscillometric amplitude. RESULTS The ANN produced better estimates of reference blood pressures than the standard oscillometric algorithm. Mean difference between target and actual output for the ANN was 0.50 +/- 5.73 mm Hg for systolic pressures, compared to the mean difference of the standard algorithm of 2.78 +/- 19.38 mm Hg. For diastolic pressures, the ANN had a mean difference of 0.04 +/- 4.70 mm Hg, while the mean difference of the standard algorithm was -0.34 +/- 9.75 mm Hg. CONCLUSIONS The ANN produced a better model of the relationship between the oscillometric envelope and reference systolic and diastolic pressures than did the standard oscillometric algorithm. Noninvasive blood pressure measured from the supraorbital artery agreed with pressure measured by auscultation in the brachial artery, and may sometimes be more clinically useful than an arm cuff device.
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Hsieh RL, Lein IN, Lee WC, Lee TK. Disability among the elderly of Taiwan. Am J Phys Med Rehabil 1995; 74:370-4. [PMID: 7576414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A cross-sectional study on the correlates of elderly disability was conducted in Taiwan. A total of 400 subjects was randomly selected according to Barthel Index scores from among 2600 subjects, which was a sample of a previous community-based health survey of elderly aged 65 or over. After comprehensive interviews and examinations of the subjects, disability dimensions and its correlates were identified. Results showed elderly with lower Mini-Mental State Examination scores and chronic diseases (such as stroke, pressure sores, hypertension, fracture, etc.) were more physical-functionally and socially disabled. This suggests that prevention and treatment of chronic diseases should be pursued further and that further assessment of cognitive-mental status in the elderly is warranted. In addition, males were more disabled than females in a physical-functional aspect, which may be the consequence of the traditional Chinese cultural effect.
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Lee TK, Silva FH, Egbert TP, Westenskow DR. Optimal sites for forehead oscillometric blood pressure monitoring. J Clin Monit Comput 1995; 11:298-304. [PMID: 7595685 DOI: 10.1007/bf01616987] [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: 01/26/2023]
Abstract
OBJECTIVE Blood pressure is usually measured noninvasively with a cuff on the arm of the leg. Circumstances exist, however, when an alternative site for blood pressure measurement is desirable. This study is designed to identify a location on the forehead where blood pressure can be reliably measured noninvasively. METHODS We mapped the superficial temporal artery and/or the supraorbital artery in 65 volunteers and found a rectangular area where an adhesive pressure pad could be placed over each artery. Oscillometric signals were recorded from four different locations over the forehead in 19 of the 65 volunteers to compare the amplitude of the signal and mean blood pressure between locations. RESULTS The course of the supraorbital artery is quite consistent. It passed through a 2.5- x 1-cm rectangular area on the forehead in all volunteers in which it was mapped. The medial border of the rectangle is 0.5-cm medial and 1-cm above the medial corner of the left eyebrow. The course of the superficial temporal artery differed remarkably from person to person. We could not find an area of reasonable size to cover the artery in all wounds. Mean blood pressures were the same in all forehead locations. The signal was the weakest on the center of the forehead and strongest directly over the superficial temporal artery. CONCLUSIONS Our results show that the supraorbital artery, an end-artery of the internal carotid artery, which emerges through the supraorbital foramen and cross the forehead near the center, is the preferred site to monitor blood pressure noninvasively on the forehead with an adhesive pressure bladder.
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Abstract
Maturation of human Protein C (HPC) precursor to a zymogen in the liver requires endoproteolytic cleavages after a basic dipeptide, Lys-2-Arg-1 in the propeptide and Lys156-Arg157 connecting the light and heavy chain. Recombinant human Protein C (rHPC) was expressed in the mammary gland of transgenic swine and its proteolytic processing was monitored. We found that about 10-20% of rHPC purified from the milk still retained the propeptide and 30-40% was in the single-chain form, indicating inefficient proteolytic cleavage. This demonstrates that endoprotease(s) of the swine mammary epithelial cells do not process fully the precursor of heterologous protein. rHPC was fractionated by anion exchange chromatography and polypeptides with novel N-termini at positions -1,152 and 157 were detected in addition to the known N-termini at residues -24, +1, and 158. Since rHPC was found to be stable both in milk and after purification, it is possible that these new cleavages on the amino side of arginine at dipeptide sites Lys-2-Arg-1, Lys151-Arg152, and Lys156-Arg157 could have occurred in the mammary gland. Thus, our results suggest that a portion of HPC precursor was proteolytically processed in swine mammary gland differently than those in other expression systems.
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Lee TK, Johnson J, Wiley AL, Means JA. Assessment of two protocols for the human lymphocyte cytokinesis-blocked micronucleus assay. Mutagenesis 1995; 10:375-7. [PMID: 7476276 DOI: 10.1093/mutage/10.4.375] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
This study indicated that by adding cytochalasin B (6 micrograms/ml) at 24 h, the lymphocyte culture time for micronucleus (MN) assay could be shortened to 64 h. In both unirradiated and ex-vivo irradiated (2 Gy) lymphocytes from three populations, we found that the differences in MN yield obtained by our modified cytokinesis-blocked time frame and that recommended by Fenech and Morley (1985) were insignificant (P = 0.66-0.87). We believe that the shorter assay time may enhance the applicability of MN assay for the rapid assessment of ionizing radiation overexposures.
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Medved LV, Orthner CL, Lubon H, Lee TK, Drohan WN, Ingham KC. Thermal stability and domain-domain interactions in natural and recombinant protein C. J Biol Chem 1995; 270:13652-9. [PMID: 7775416 DOI: 10.1074/jbc.270.23.13652] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Scanning microcalorimetry and spectrofluorimetry were applied to a study of the thermal stability and interaction of the modules within natural human protein C (PC) and recombinant protein C (rPC), a potential therapeutic anticoagulant expressed in transgenic pigs. Upon heating in the presence of 2 mM EDTA, pH 8.5, each protein exhibited a similar heat absorption peak with a Tm of approximately 62 degrees C corresponding to the melting of the serine protease (SP) module. Deconvolution of this peak indicated that the SP module consists of two domains that unfold independently. At pH below 3.8, a second peak appeared at extremely high temperature corresponding to the unfolding of the two interacting epidermal growth factor-like (EGF) domains. This second peak occurred at a temperature about 20 degrees C lower in rPC than in PC indicating that the EGF domains in the recombinant protein are less stable. The isolated 6-kDa gamma-carboxyglutamic acid-rich (Gla) fragment as well as a 25-kDa Gla-(EGF)2 fragment both exhibited a sigmoidal fluorescence-detected denaturation transition in the same temperature region as the SP domains, but only in the presence of Ca2+. In 2 mM Ca2+, the first heat absorption peak in both intact proteins became biphasic, indicating Ca(2+)-induced structural changes. By contrast, Ca2+ had very little effect on the melting of Gla-domain-less protein C. This indicates that not Ca2+ itself but the Ca(2+)-loaded Gla domain is responsible for conformational changes in the SP domain of the parent protein. Detailed analysis of the shape of the endotherms obtained in Ca2+ and EDTA suggests that Ca2+ induces compact structure in the Gla domain which appears to interact strongly with the SP domain(s) of protein C.
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Lee TK, Rollence ML, Hallberg PL, Oelkuct MS, Dodd SW, Nagle JW, Filpula DR. Production of engineered IgM-binding single-chain antibodies in Escherichia coli. JOURNAL OF INDUSTRIAL MICROBIOLOGY 1995; 14:371-6. [PMID: 7612215 DOI: 10.1007/bf01569953] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Two single-chain antibodies were engineered and tested as novel binding proteins with specificity for immunoglobulin M. Genes for the two single-chain Fv proteins were assembled from the variable light chain cDNA and variable heavy chain cDNA of monoclonal antibodies DA4.4 and Bet 2, which specifically bind human IgM and mouse IgM, respectively. Both single-chain Fv proteins were designed with a 14-amino acid linker which bridged the variable light chain and variable heavy chain domains. The two proteins were expressed in Escherichia coli, purified and assayed for IgM-binding activity. Both proteins demonstrate a binding specificity for their corresponding IgM which is similar to the monoclonal antibodies from which they were derived. These small IgM-binding proteins may have applications in the investigation of the immune response and in the detection and purification of monoclonal antibodies, cell-associated antibodies, and IgM from serum.
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Lee TK, Huang ZS, Ng SK, Chan KW, Wang YS, Liu HW, Lee JJ. Impact of alcohol consumption and cigarette smoking on stroke among the elderly in Taiwan. Stroke 1995; 26:790-4. [PMID: 7740568 DOI: 10.1161/01.str.26.5.790] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND AND PURPOSE We investigated the influence of alcohol consumption and cigarette smoking on all types of stroke and cerebral infarction, in particular among a representative sample of elderly residents in Taiwan. METHODS This study was a component of a nationwide survey of health and living status of residents aged 65 years or older in Taiwan in which subjects received detailed physical, neurological, and laboratory examinations. Inquiries were made about medical history, and information on the amount and duration of drinking and smoking was obtained. Diagnoses of stroke were made according to the results of brain computed tomography at the onset of disease or were based on criteria established by the World Health Organization. RESULTS Of the 2600 subjects, there were 155 elderly persons with stroke (prevalence, 6%). Excessive drinking of more than 367.6 g/wk of alcohol was associated with a high prevalence of cerebral infarction. Consumption of < or = 367.5 g/wk of alcohol did not have an influence on stroke prevalence. The relationship between duration of alcohol drinking and stroke was equivocal. More than 30 pack-years of cigarette smoking was a significant risk factor for all types of stroke and cerebral infarction in particular. Using multiple logistic regression to control for possible confounders, it was found that smoking was an independent risk factors for all stroke and was of borderline significance for cerebral infarction. Although excessive drinking was a significant risk factor for cerebral infarction in univariate analysis, this effect was lost after adjustment for other confounders. CONCLUSIONS Cigarette smoking was a more important risk factor for stroke and cerebral infarction than excessive drinking of alcohol.
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