651
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Chu S, Park Y, Locke C, Wilson DS, Cavanaugh JC. Drug-food interaction potential of clarithromycin, a new macrolide antimicrobial. J Clin Pharmacol 1992; 32:32-6. [PMID: 1531484 DOI: 10.1002/j.1552-4604.1992.tb03784.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
To evaluate the effect of food on bioavailability, clarithromycin and 14-hydroxyclarithromycin (active metabolite) pharmacokinetics were assessed in 26 healthy adult volunteers after ingestion of a single oral 500-mg dose of clarithromycin in a fasting state (2 hours before breakfast after an overnight fast) and a nonfasting state (0.5 hours after the start of breakfast). Clarithromycin and 14-hydroxy metabolite plasma concentrations were measured using a high-performance liquid chromatographic technique. Food intake immediately before dosing increased the extent of absorption from the 500-mg tablet formulation by approximately 25%. The mean increase in metabolite area under the plasma concentration-time curve was approximately 9%. These results suggest that clarithromycin can be taken without regard to timing in relation to meals.
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652
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Park Y, Devlin TM, Majde JA, Jones DP. Protective effect of dicalciphor during mitochondrial failure. Ren Fail 1992; 14:303-6. [PMID: 1509161 DOI: 10.3109/08860229209106633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Mammalian cells differ considerably in the duration of anoxia which they can tolerate despite the fact that dramatic bioenergetic changes occur rapidly. Previous studies indicate that the ability to tolerate anoxia is at least partly due to an endogenous signal transduction system that senses O2 deficiency and signal altered ion transport functions in the mitochondria. The responses included inhibition of ATP synthase, ADP/ATP exchange, inorganic phosphate uptake, mitochondrial swelling, and loss of the mitochondrial proton-motive force. An important distinction between KCN toxicity and anoxia is that KCN does not elicit these protective mechanisms. Thus, the ability of a compound to elicit these mechanisms in KCN-treated cells provides an assay for potential agonists of the endogenous protective mechanisms.
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653
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Kowalski DP, Aw TY, Park Y, Jones DP. Postanoxic oxidative injury in rat hepatocytes: lactate-dependent protection against tert-butylhydroperoxide. Free Radic Biol Med 1992; 12:205-12. [PMID: 1563646 DOI: 10.1016/0891-5849(92)90028-f] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Previous studies in this laboratory showed that hypoxia and anoxia enhance the susceptibility of hepatocytes to tert-butylhydroperoxide (TBH)-induced oxidative injury. To determine whether preceding exposure to anoxia affects postanoxic sensitivity to oxidative injury, viability was studied in hepatocytes incubated under anoxic conditions followed by reoxygenation without or with tert-butylhydroperoxide addition. Results showed that a preceding exposure to 60 min of anoxia substantially increased the vulnerability of cells to injury by the oxidant. Because substantial tissue lactate can accumulate during anoxia, the effect of increased lactate on postanoxic injury due to TBH was determined. Results showed that added lactate protected in a concentration-dependent manner. The TBH elimination rate was stimulated by lactate, and the pyruvate production rate approached the rate of TBH elimination. Thus, lactate protects against postanoxic oxidative injury by supplying reducing equivalents for peroxide reduction. This suggests that lactate accumulation during ischemia may be beneficial and that supplementation with lactate could be considered as a means to protect against postischemic injury.
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654
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Park Y, Kanekal S, Kehrer JP. Oxidative changes in hypoxic rat heart tissue. THE AMERICAN JOURNAL OF PHYSIOLOGY 1991; 260:H1395-405. [PMID: 2035661 DOI: 10.1152/ajpheart.1991.260.5.h1395] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Reactive O2 species appear to be generated both during hypoxia and at reoxygenation, but it has not been established whether these species interact with heart tissue and cause injury. Oxidative changes were evaluated in isolated rat heart perfused with Krebs-Henseleit medium containing 10 mM glucose and 2.5 mM calcium. After 5-10 min hypoxia, tissue glutathione (GSH) decreased while glutathione disulfide (GSSG), protein carbonyls, and thiobarbituric acid reactive substances (TBARS) increased compared with controls. Similarly, sarcolemmal and sarcoplasmic reticular Ca-ATPase activity (an enzyme susceptible to oxidative inactivation) decreased in response to 10 min hypoxia. These changes were more pronounced after 60 min of hypoxia when protein-GSH mixed disulfides were also increased. There were no further oxidative changes after 4 min reoxygenation when the release of lactate dehydrogenase (LDH) was maximal. Myocardial protein thiol and alpha-tocopherol contents were not significantly changed by either hypoxia or reoxygenation. Mitochondria also exhibited oxidative changes but with more pronounced increases in GSSG and mixed disulfides. There was no change in GSH or GSSG efflux into the coronary effluent during hypoxia, although, in parallel with LDH release, both increased after reoxygenation. Diamide (200 microM), t-butylhydroperoxide (20 microM), or purine (2.3 mM) + xanthine oxidase (0.01 U/ml) were infused for 10 min. Except for large diamide-induced changes in protein thiols and mixed disulfides, the magnitude of the changes produced by these oxidants was similar to those produced by hypoxia. These data show that changes consistent with oxidative processes occur in whole heart and mitochondria in response to hypoxia. The absence of marked signs of oxidation at reoxygenation suggest that enzyme release at this time is unrelated to oxidative stress.
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655
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Kehrer JP, Park Y. Purity of ruthenium red used in pharmacological research. JOURNAL OF PHARMACOLOGICAL METHODS 1991; 25:179-83. [PMID: 1712417 DOI: 10.1016/0160-5402(91)90008-s] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The inorganic dye, ruthenium red, is an ammoniated form of ruthenium oxychloride. The purity of commercial samples of ruthenium red has been confused as commercial vendors often provide a "dye content" figure for their product, which some investigators have equated with purity. However, dye content is the same as ruthenium content and is not related to purity, although it will affect the relative molecular weight of this compound. As a result, concentrations of ruthenium red used in various biochemical studies have been calculated based on the supposed impurity of the commercial product, a product purified in the laboratory of the investigator, or by simply ignoring this purity question. Purity of four different commercial products as well as two different "purified" materials was determined by comparison of absorbance spectra and extinction coefficients. Taking into account differences in the relative ruthenium content of each preparation of ruthenium red, the results demonstrate no significant differences between these materials indicating that commercially available samples of ruthenium red are essentially pure.
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656
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Onishi N, Uchida A, Kiwamoto H, Esa A, Sugiyamka T, Park Y, Akiyama T, Kurita T. [Management of vesicoureteral reflux in patients with neurogenic bladder dysfunction]. Nihon Hinyokika Gakkai Zasshi 1991; 82:473-80. [PMID: 2072609 DOI: 10.5980/jpnjurol1989.82.473] [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: 12/30/2022]
Abstract
We studied 20 cases of neurogenic bladder with vesico-ureteral reflux retrospectively. Seven patients voided with Valsalva's maneuver and 12 patients were managed with clean intermittent catheterization, but one patient required permanent urinary diversion because of uncontrollable urinary tract infection. The patients were followed by intravenous pyelography, radioisotope renogram, voiding cystourethrography, determination of serum creatinine level and urodynamic study. Anti-reflux surgery was performed in 22 ureters and reflux resolved in 19 ureters. Among 12 ureters not treated by anti-reflux surgery, reflux disappeared in 5 ureters and improved in 2 ureters. Of 5 ureters, reflux resolved after clean intermittent catheterization in 2 ureters, and remained stable without recurrent infection or renal deterioration in the remaining 5 ureters. Regardless whether antireflux surgery was done or not, most of the patients who had high grade reflux and obstructive renal damage on radioisotope examinations had marked low compliance bladders. Our experience suggested the necessity of a suitable treatment to improve bladder compliance before considering anti-reflux surgery.
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657
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Park Y, Kehrer JP. Oxidative changes in hypoxic-reoxygenated rabbit heart: a consequence of hypoxia rather than reoxygenation. FREE RADICAL RESEARCH COMMUNICATIONS 1991; 14:179-85. [PMID: 2060863 DOI: 10.3109/10715769109088947] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Tissue changes consistent with oxidative damage in hypoxic/reoxygenated heart tissue have not been well documented. We recently reported that oxidative perturbations were evident in isolated-perfused rat heart tissue subjected to as little as 10 min hypoxia and that these changes were not exacerbated by reoxygenation. The mechanism and species specificity of this finding is not known. Rabbit hearts, which lack measurable xanthine oxidase activity, were examined for evidence of hypoxia-induced injury. The release of lactate dehydrogenase into the coronary effluent gradually increased during the retrograde perfusion of isolated rabbit hearts with hypoxic medium (containing 10 mM glucose and 2.5 mM calcium), and was slightly enhanced upon reoxygenation after 60 min hypoxia. Cardiac glutathione content decreased significantly while glutathione disulfide, protein-glutathione mixed disulfides, thiobaribturic acid reactive substances (TBARS), and protein carbonyl contents increased significantly after 60 min of hypoxia, compared to oxygenated controls. These values were unaltered after 4 min of reoxygenation except for a loss of TBARS. The oxidative changes observed in hypoxic rabbit hearts may be caused by energy deficiency impairing normal reductive processes or by the generation of reactive oxygen species as a result of abnormal cell functions, but cannot be related to xanthine oxidase activity.
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658
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Kehrer JP, Park Y. Oxidative stress during hypoxia in isolated-perfused rat heart. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1991; 283:299-304. [PMID: 2069001 DOI: 10.1007/978-1-4684-5877-0_36] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
These data suggest that oxidative stress occurs at the low oxygen tensions which exist during perfusion of rat heart tissue with hypoxic medium. Importantly, no evidence was found for additional oxidative injury after 4 min reoxygenation when enzyme release is maximal in this system suggesting the oxygen paradox is unrelated to oxidative stress. However, the oxidative changes evident after 10-15 min of hypoxia do support the occurrence of free radical mediated injury at low oxygen tensions, and it is possible this injury is involved in the changes which lead to cell lysis at reoxygenation. The source of this oxidative stress is not known, but appears to be greater in mitochondria and may arise from an increased production of reactive oxygen species by this organelle. Whether the observed oxidative changes are directly injurious to a cell is not yet clear.
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659
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Park Y, Bowles DK, Kehrer JP. Protection against hypoxic injury in isolated-perfused rat heart by ruthenium red. J Pharmacol Exp Ther 1990; 253:628-35. [PMID: 1692589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Changes in intracellular calcium content and energy production during the period of hypoxia appear to be necessary for the development of cellular injury. Ruthenium red, a hexavalent dye which inhibits the active uptake of calcium by mitochondria, might improve a cell's energy status thereby minimizing hypoxic injury. Rat heart tissue was perfused retrogradely with Krebs-Henseleit medium containing 2.5 mM calcium and 10 mM glucose. The infusion of 0.1, 1.0 or 1.24, but not 0.01 microM, ruthenium red throughout 60 min of hypoxia and 30 min of reoxygenation decreased, in a dose-dependent manner, the release of lactate dehydrogenase normally seen at reoxygenation. When the infusion of 1.24 microM ruthenium red was begun after 45 min of hypoxia, lactate dehydrogenase release at reoxygenation after 60 min of hypoxia was decreased, but to a lesser extent than when this agent was present throughout hypoxia. Ruthenium red, 1.24 microM, had no significant effects on coronary flow or function in oxygenated heart tissue. When present throughout hypoxia and reoxygenation, 1.24 microM ruthenium red prevented the decrease in coronary flow normally seen and allowed recovery of heart rate, +dP/dT, -dP/dT and work (defined as the product of developed pressure and heart rate) to normal levels. Significant functional protection was not evident at reoxygenation when ruthenium red was infused after 45 min of hypoxia or in the absence of glucose. Cardiac ATP, creatine phosphate and energy charge were decreased after 60 min of hypoxia.(ABSTRACT TRUNCATED AT 250 WORDS)
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660
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Park Y, el-Bayer H, Hye RJ, Stabile BE, Freischlag JA. Safety and long-term benefit of carotid endarterectomy in the asymptomatic patient. Ann Vasc Surg 1990; 4:218-22. [PMID: 2340242 DOI: 10.1007/bf02009447] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In order to determine the safety and long-term salutary effects of carotid endarterectomy in the asymptomatic patient, we retrospectively reviewed all asymptomatic patients who underwent carotid endarterectomy from 1980 through 1986. There were 60 carotid endarterectomies performed in 54 patients, 53 men and one woman. The mean age was 64 years. Arteriography revealed a high grade stenosis of 70% or greater in 46 carotid arteries (77%), ulceration in five (8%), and both in nine (15%). Risk factors included coronary artery disease in 60% of patients, smoking in 87%, hypertension in 67%, and diabetes in 22%. Perioperative morbidity included three cranial nerve injuries, one myocardial infarction and one contralateral stroke. There were no deaths. Mean follow-up was 47 months with only two patients being lost to follow-up. During follow-up three patients suffered ipsilateral transient ischemic attacks without recurrent carotid stenosis and one patient had a transient ischemic attack secondary to contralateral carotid occlusion. There was one ipsilateral stroke occurring two years after operation secondary to restenosis that required reoperation and four late contralateral strokes. Ten patients died in the follow-up period. Causes of death were stroke (1), cardiac (4), malignancy (2), pulmonary (2), and unknown (1). All surviving patients were evaluated by duplex scan at a mean interval following surgery of 47 months. Restenosis of endarterectomized arteries was seen at the following rates: less than 50% in 41 (87%); 50-75% in four (8.5%); 80% in one (2%); and 90% in one (2%). Life table analysis revealed a 98% ipsilateral stroke-free rate at five and eight years.(ABSTRACT TRUNCATED AT 250 WORDS)
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661
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Di Bisceglie AM, Rustgi VK, Kassianides C, Lisker-Melman M, Park Y, Waggoner JG, Hoofnagle JH. Therapy of chronic hepatitis B with recombinant human alpha and gamma interferon. Hepatology 1990; 11:266-70. [PMID: 2106474 DOI: 10.1002/hep.1840110217] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Eight patients with chronic hepatitis B entered a pilot study of gamma interferon and alpha interferon in combination. Gamma interferon alone had minimal inhibitory effects on serum levels of hepatitis B virus as monitored by serum HBV DNA and DNA-polymerase activity. The drug also gave troublesome side effects. In contrast, alpha interferon had more potent inhibitory effects on serum HBV levels and fewer side effects. When combined, the two interferons showed no additive or synergistic effects in inhibiting serum levels of HBV DNA or DNA polymerase. These findings indicate that the addition of gamma interferon to alpha interferon provides no additional antiviral effects but contributes significantly to side effects.
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662
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Kim K, Lee BJ, Park Y, Cho WK. Progesterone increases messenger ribonucleic acid (mRNA) encoding luteinizing hormone releasing hormone (LHRH) level in the hypothalamus of ovariectomized estradiol-primed prepubertal rats. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1989; 6:151-8. [PMID: 2693878 DOI: 10.1016/0169-328x(89)90049-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In order to investigate the mechanism underlying ovarian steroid action on gene expression of hypothalamic luteinizing hormone releasing hormone (LHRH), changes in LHRH mRNA level were determined by RNA-blot hybridization assay. Twenty-eight-day-old female rats were ovariectomized (OVX) and implanted with Silastic capsule containing either 17 beta-estradiol (E) or vehicle (V). Two days later (day 30), OVX + E-primed rats were given s.c. progesterone (P, 1 mg) 6 h prior to decapitation. Four experimental groups were studied: (1) intact, (2) OVX + V, (3) OVX + E, and (4) OVX + E + P-treated rats. Poly(A) RNA fractions from hypothalami (40-50/group) were isolated, blotted onto nitrocellulose paper and hybridized with 32P-end-labeled LHRH oligonucleotides (29 mer) which are complementary to rat LHRH mRNA. The hypothalamic LHRH mRNA signal markedly attenuated 2 days following ovariectomy. E replacement to OVX rats slightly increased LHRH mRNA level, which is lower than that of the intact group. However, a single injection of P to OVX + E-treated rats notably augmented the LHRH mRNA level over that observed in the intact group. In addition, LHRH content and release in vitro were examined to correlate with changes in LHRH gene expression. Ovariectomy and the replacement of E and/or P resulted in a similar fashion of changes in LHRH release and content as compared to alteration of LHRH mRNA level. This study clearly demonstrates that P increases LHRH mRNA level in the hypothalamus of OVX + E-primed immature rats.(ABSTRACT TRUNCATED AT 250 WORDS)
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663
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Lisker-Melman M, Webb D, Di Bisceglie AM, Kassianides C, Martin P, Rustgi V, Waggoner JG, Park Y, Hoofnagle JH. Glomerulonephritis caused by chronic hepatitis B virus infection: treatment with recombinant human alpha-interferon. Ann Intern Med 1989; 111:479-83. [PMID: 2774373 DOI: 10.7326/0003-4819-111-6-479] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
STUDY OBJECTIVES To assess the efficacy of alpha-interferon therapy in patients with hepatitis B virus (HBV)-related glomerulonephritis. DESIGN Prospective, nonrandomized study. PATIENTS Five patients with persistence of hepatitis B surface antigen, hepatitis B e antigen (HBeAg) and HBV DNA in serum for at least 6 months and histologic changes of chronic hepatitis on liver biopsy as well as persistent proteinuria of greater than 2 g/d and histologic changes of glomerulonephritis on renal biopsy. INTERVENTIONS Patients received a 4-month course of recombinant human alpha-interferon (alfa-2b) beginning at a dose of 5 million units administered subcutaneously each day. RESULTS Serum levels of HBV DNA decreased in all patients and fell to undetectable levels during treatment in four of five patients. In the four responding patients, serum HBeAg disappeared, aminotransferases fell into the normal range, and a follow-up liver biopsy showed an improvement in the hepatocyte necrosis and inflammation. Urine protein excretion also decreased during treatment. In the four responding patients, urine protein excretion gradually fell to less than 1 g/d and serum albumin levels rose into the normal range. Resolution of the biochemical and serologic evidence of chronic hepatitis and glomerulonephritis was accompanied by disappearance of signs and symptoms of liver and kidney disease. CONCLUSIONS A high proportion of patients with HBV-related glomerulonephritis will respond to a 4-month course of alpha-interferon with a clinical, biochemical, and serologic remission.
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664
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Park Y, Smith RD, Combs AB, Kehrer JP. Prevention of acetaminophen-induced hepatotoxicity by dimethyl sulfoxide. Toxicology 1988; 52:165-75. [PMID: 3188030 DOI: 10.1016/0300-483x(88)90202-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Dimethyl sulfoxide (DMSO) has previously been shown to protect against acetaminophen (APAP)-induced hepatotoxicity, but the mechanism of this effect was not clear. Treatment of mice with 1 mg/kg DMSO 4 h before 250 mg/kg APAP resulted in significantly less hepatotoxicity than with APAP alone, as measured by serum glutamic pyruvic transaminase (SGPT) content 24 h after APAP. Protection was also evident when 1 ml/kg DMSO was given 4, but not 8 h after 250 mg/kg APAP. The APAP-induced depletion of liver glutathione was prevented in mice pretreated with DMSO, although DMSO alone had no effect on liver glutathione levels. The hepatic concentration of cytochrome P-450 (P450) 4 h after treatment of mice with 1 ml/kg DMSO, was significantly decreased compared to saline-treated animals. However, while this DMSO pretreatment significantly decreased the activity of cytochrome P-450-linked aminopyrine-N-demethylase, it increased the activity of aniline hydroxylase. Covalent binding of [14C]APAP to hepatic protein in vivo was significantly decreased in mice pretreated with DMSO. Covalent binding of [14C]APAP to hepatic microsomal protein in vitro was not significantly altered after in vivo treatment with DMSO. However, the presence of DMSO in the in vitro incubation mixture significantly decreased covalent binding of [14C]APAP in a dose-dependent manner compared to microsomal fractions from untreated, saline-treated or DMSO pretreated animals. These data suggest that the DMSO-induced alterations in cytochrome P-450 content and activity may not be the cause of the observed protective action of this chemical. The ability to competitively inhibit APAP bioactivation or to directly scavenge free radicals produced during APAP metabolism, including the activated species which covalently binds to protein, may account for the hepatoprotection afforded by DMSO.
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665
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Hoofnagle JH, Peters M, Mullen KD, Jones DB, Rustgi V, Di Bisceglie A, Hallahan C, Park Y, Meschievitz C, Jones EA. Randomized, controlled trial of recombinant human alpha-interferon in patients with chronic hepatitis B. Gastroenterology 1988; 95:1318-25. [PMID: 3049216 DOI: 10.1016/0016-5085(88)90367-8] [Citation(s) in RCA: 339] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Forty-five patients with chronic hepatitis B were entered into a randomized controlled trial of recombinant human alpha-interferon therapy. All patients had hepatitis B surface antigen in serum for at least 1 yr and had stable serum levels of both hepatitis B virus deoxyribonucleic acid and hepatitis B e antigen. During the 4-mo period of therapy, 10 of 31 (32%) treated patients and only 1 of 14 (7%) control patients became negative for serum hepatitis B virus deoxyribonucleic acid and deoxyribonucleic acid polymerase. All 10 patients who became negative for serum hepatitis B virus deoxyribonucleic acid subsequently had a marked improvement in serum aminotransferase activities and lost hepatitis B e antigen from serum, and 9 of them had improvement in liver histology. Comparison of responders to nonresponders indicated that female sex and a high initial level of serum aspartate aminotransferase correlated best with response to interferon therapy. These findings indicate that a 4-mo course of recombinant alpha-interferon can induce a remission in disease in approximately one-third of patients with chronic hepatitis B.
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666
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Samojlik E, Lippman AJ, Kirschner MA, Ertel NH, Park Y, Szmal E. Medical adrenalectomy for advanced prostatic cancer: clinical and hormonal effects. Am J Clin Oncol 1988; 11:579-85. [PMID: 3177260 DOI: 10.1097/00000421-198810000-00014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We examined the effect of medical adrenalectomy on the clinical and hormonal responses in 50 men with disseminated prostatic carcinoma. Patients refractory to initial hormonal therapy were treated with aminoglutethimide and hydrocortisone (AG-HC) and evaluated by the criteria of the National Prostatic Cancer Project. Eight patients showed a partial response (PR), and 17 remained stable while receiving these medications. Survival times for these two groups averaged 87.8 and 38 weeks, respectively. In contrast, 17 men were unresponsive to this therapy, exhibiting progressive disease with a mean survival time of 18 weeks. Eight patients could not tolerate the drug regimen or were lost to follow-up. Serum and urinary hormone profiles determined serially during AG-HC therapy revealed that all measured serum androgens and estrogens were significantly lowered by AG-HC treatment; however, specific hormones, including free testosterone, dihydrotestosterone, estrone, and estradiol were suppressed to a greater degree in responders (R) as compared with nonresponders (NR). Urinary excretion of 17-ketosteroids did not change during AG-HC therapy, but specific androgen metabolites, including testosterone glucuronide and androstanediol glucuronide, were suppressed by 50% during AG-HC therapy. We showed modest clinical benefit of AG-HC therapy in advanced prostatic cancer. That greater hormonal suppression was associated with greater responsiveness to this therapy raises the hope that further manipulations directed against suppression of extratesticular androgens may be a useful approach as second-line treatment of advanced prostatic cancer.
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667
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Kehrer JP, Park Y, Sies H. Energy dependence of enzyme release from hypoxic isolated perfused rat heart tissue. J Appl Physiol (1985) 1988; 65:1855-60. [PMID: 3182545 DOI: 10.1152/jappl.1988.65.4.1855] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
There is a sudden release of intracellular constituents upon reoxygenation of isolated perfused hypoxic heart tissue (O2 paradox) or on perfusion with calcium-free medium after a period of hypoxia. Rat hearts were perfused by the method of Langendorff (Pfluegers Arch. 61: 291-332, 1895) with Krebs-Henseleit medium containing 10 mM glucose. Hearts were equilibrated for 30 min, followed by 90 min of hypoxia or 60 min of hypoxia and 30 min of reoxygenation. The massive enzyme release observed upon reoxygenation after 60 min of hypoxia was prevented by infusing 0.5 or 5 mM cyanide 5 min before reoxygenation. Lactate dehydrogenase (LDH) release commenced immediately upon withdrawal of cyanide. Hearts perfused with calcium-free medium throughout hypoxia did not release increased amounts of LDH at reoxygenation. Perfusing heart tissue with medium containing 0 or 25 microM calcium, but not 0.25 or 2.5 mM, after 50 min of hypoxia initiated a release of cardiac LDH, which was not further enhanced by reoxygenation. Enzyme release was significantly inhibited when the calcium-free perfusion medium included 10 mM 2-deoxyglucose (replacing glucose), 0.5 mM dinitrophenol, or 2.5 mM cyanide. Histologically, hearts perfused with calcium-free medium after 50 min of hypoxia showed areas of severe necrosis and contracture without any evidence of the contraction bands that were seen in hearts reoxygenated in the presence of calcium. Cardiac ATP and creatine phosphate (PCr) levels were significantly decreased after 50-60 min of hypoxia.(ABSTRACT TRUNCATED AT 250 WORDS)
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668
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Esa A, Ikegami M, Sugiyama T, Park Y, Kurita T, Kaneko S, Iimori M. [Bacterial and clinical studies of disinfectants for self-catheterization]. Nihon Hinyokika Gakkai Zasshi 1988; 79:1663-8. [PMID: 3251101 DOI: 10.5980/jpnjurol1928.79.10_1663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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669
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Darlow LD, Murphy JB, Berrios RJ, Park Y, Feldman RS. Arteriovenous malformation of the maxillary sinus: an unusual clinical presentation. ORAL SURGERY, ORAL MEDICINE, AND ORAL PATHOLOGY 1988; 66:21-3. [PMID: 3043306 DOI: 10.1016/0030-4220(88)90059-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Arteriovenous (AV) malformation is a rare vascular lesion of the jaws with a benign clinical presentation. As a result, AV malformation may be excluded from a presurgical differential diagnosis, with catastrophic results. Review of the pertinent literature showed no documentation of AV malformation in the maxillary sinus, and therefore we present the case of a 43-year-old white man with a history of blunt trauma to the paranasal region, whose differential diagnosis included a vascular lesion.
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670
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Park Y, Kim J, Kim D. Superconducting-normal phase boundary of a random network in magnetic fields. PHYSICAL REVIEW. B, CONDENSED MATTER 1988; 38:741-744. [PMID: 9945242 DOI: 10.1103/physrevb.38.741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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671
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Park Y, Park SD, Cho WK, Kim K. Testosterone stimulates LH-RH-like mRNA level in the rat hypothalamus. Brain Res 1988; 451:255-60. [PMID: 3075143 DOI: 10.1016/0006-8993(88)90770-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
To elucidate whether testosterone (T) replacement to castrated male rats may promote luteinizing hormone-releasing hormone (LH-RH) biosynthesis in the hypothalamus, an RNA-blot hybridization assay was employed. Poly(A) mRNA fractions from hypothalami (40-50) of intact, castrated plus vehicle, and castrated plus T group were isolated, blotted on nitrocellulose paper and hybridized with 32P-end labelled LH-RH oligonucleotides (29 mer) which is complementary to the rat LH-RH mRNA. LH-RH-like mRNA level markedly attenuated 2 weeks following castration and T replacement significantly increased LH-RH-like mRNA level, comparable to about 80% of that observed in intact male rats. In addition, LH-RH contents and release from hypothalami were studied, to examine the correlation with LH-RH gene expression and secretory activity of LH-RH. Castration significantly reduced LH-RH contents and LH-RH release in vitro. T replacement restored LH-RH contents and release comparable to those shown in the intact group. This study demonstrates for the first time that T replacement increases LH-RH-like mRNA level in the hypothalami of castrated rats suggesting that T may act at the pretranslational level. This change in LH-RH gene expression is parallel with alteration of LH-RH content and release.
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672
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Chan T, Levine MS, Park Y. Cholesterol embolization as a cause of cecal infarct mimicking carcinoma. AJR Am J Roentgenol 1988; 150:1315-6. [PMID: 3259371 DOI: 10.2214/ajr.150.6.1315] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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673
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Park Y, Lubensky TC, Barois P, Prost J. New critical point in smectic liquid crystals. PHYSICAL REVIEW. A, GENERAL PHYSICS 1988; 37:2197-2213. [PMID: 9899915 DOI: 10.1103/physreva.37.2197] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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674
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Park Y, Suzuki H, Lee YS, Hayakawa S, Wada S. Effect of coix on plasma, liver, and fecal lipid components in the rat fed on lard- or soybean oil-cholesterol diet. BIOCHEMICAL MEDICINE AND METABOLIC BIOLOGY 1988; 39:11-7. [PMID: 3355708 DOI: 10.1016/0885-4505(88)90052-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
To determine the influence of dietary coix on lipid metabolism, the effect of coix on plasma, liver, and fecal lipid components was studied using Sprague-Dawley male rats. All rats were divided into four groups, and the rats of each group were fed the coix-lard diet, coix-soybean oil diet, or the respective control diets (containing 1% cholesterol each) for 27 days. Plasma and liver cholesterol levels in the coix-lard diet group significantly decreased as compared with those in the control group, whereas there was no effect on the fecal excretion of cholesterol. The decreases in the concentrated liver triglyceride and the increases in the fecal excretion of triglyceride were found in coix-soybean oil diet group. Moreover, liver and fecal phospholipid levels in both coix diet groups significantly increased. But there were no significant changes in plasma and fecal bile acids in either coix diet group. These results suggest the possibilities that coix may have an inhibitory action on cholesterol synthesis in liver, a facilitating effect on biliary excretion of triglyceride, and an acceleratory action on phospholipid synthesis in liver.
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675
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Renault PF, Hoofnagle JH, Park Y, Mullen KD, Peters M, Jones DB, Rustgi V, Jones EA. Psychiatric complications of long-term interferon alfa therapy. ARCHIVES OF INTERNAL MEDICINE 1987; 147:1577-80. [PMID: 3307672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Ten (17%) of 58 patients with chronic viral hepatitis treated with a four- to 12-month course of recombinant human interferon alfa developed psychiatric side effects. The psychiatric side effects fell into three categories: an organic personality syndrome characterized by irritability and short temper; an organic affective syndrome marked by extreme emotional lability, depression, and tearfulness; and a delirium marked by clouding of consciousness, agitation, paranoia, and suicidal potential. These psychiatric side effects appeared after one to three months of therapy, usually improved within three to four days of decreasing the dose of interferon alfa, and invariably resolved once therapy was stopped. The organic personality and affective syndromes tended to occur in patients who received the highest dose of interferon alfa, who had relatively mild hepatitis, and who lost weight during interferon treatment. Delirium tended to occur in patients with severe hepatitis who had previous evidence of organic brain injury or dysfunction or previous drug and alcohol abuse. Failure to recognize these side effects quickly and to treat them with supportive therapy and modification of the dose of interferon alfa could result in limitation of therapy and serious personal and interpersonal consequences.
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676
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Park Y, Harris AB, Lubensky TC. Noise exponents of the random resistor network. PHYSICAL REVIEW. B, CONDENSED MATTER 1987; 35:5048-5055. [PMID: 9940688 DOI: 10.1103/physrevb.35.5048] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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677
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Hoofnagle JH, Mullen KD, Jones DB, Rustgi V, Di Bisceglie A, Peters M, Waggoner JG, Park Y, Jones EA. Treatment of chronic non-A,non-B hepatitis with recombinant human alpha interferon. A preliminary report. N Engl J Med 1986; 315:1575-8. [PMID: 3097544 DOI: 10.1056/nejm198612183152503] [Citation(s) in RCA: 634] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We treated 10 patients who had chronic non-A,non-B hepatitis with recombinant human alpha interferon in varying doses (0.5 to 5 million units) daily, every other day, or three times weekly for up to 12 months. In 8 of the 10 patients, elevated serum aminotransferase levels decreased rapidly during therapy and eventually fell into the normal or nearly normal range. In two of these patients, the interferon therapy was stopped after four months, and in both cases, a prompt return of aminotransferase activities to pretreatment values occurred. Prolonged treatment was associated with a sustained improvement in aminotransferase levels; in three cases, biopsy specimens obtained after one year of therapy showed marked improvement in hepatic histology, even though low doses of alpha interferon had been used. These preliminary findings, although not adequately controlled, suggest that long-term, low-dose alpha interferon therapy may be effective in controlling the disease activity in some patients with chronic non-A,non-B hepatitis. A prospective controlled trial is now needed to assess the role of interferon therapy in this disease.
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678
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Sasaki M, Esa A, Park Y, Kaneko S, Kurita T, Sugiyama T. [The introduction of an urodynamic technic synchronized with videocystourethrograms and its data management]. HINYOKIKA KIYO. ACTA UROLOGICA JAPONICA 1985; 31:2135-40. [PMID: 3832917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The video urodynamics that simultaneously display urodynamic data with radiographic visualization of the lower urinary tract on television monitors was first described by Miller in 1967. This technique has been developed in a growing number of urodynamic laboratories in North American and European countries. The 2100 uro color video system manufactured by DISA elektronik A/S was introduced into our clinic in September in 1984. We have been aware of the lack of a satisfactory way of measuring the function of the bladder neck and posterior urethra during micturiton. But now, from our experience using this system, we conclude that video urodynamics is a comprehensive means of assessing, lower urinary tract disorders.
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679
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Nagata S, Park Y, Minamikawa T, Yutani C, Kamiya T, Nishimura T, Kozuka T, Sakakibara H, Nimura Y. Thallium perfusion and cardiac enzyme abnormalities in patients with familial hypertrophic cardiomyopathy. Am Heart J 1985; 109:1317-22. [PMID: 4039883 DOI: 10.1016/0002-8703(85)90358-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Twelve patients of five families with familial hypertrophic cardiomyopathy were examined. Within each family, the older patients showed dilation or diminished contraction of the left ventricle by echocardiography or angiocardiography more frequently than did younger patients. LDH1 fraction (lactic dehydrogenase isoenzyme) and MB-CPK (creatinine phosphokinase isoenzyme) were increased in 7 of 10 patients. Thallium-201 myocardial scintigraphy showed perfusion defect or hypoperfusion in 9 of 10 patient. Eleven cases demonstrated remarkable hypertrophy at the macroscopic level. Marked fibrosis was observed in all 5 of the 11 patients whose histologic findings were obtained. In two necropsy cases, disarray was found throughout the right and left ventricles and the pattern of fibrosis was massive. These findings were different from those of ordinary hypertrophic cardiomyopathy. It is possible that each patient with familial hypertrophic cardiomyopathy may develop more prominent thallium and enzyme abnormalities as he becomes older, regardless of whether he develops a dilated cardiomyopathy picture.
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680
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Lee K, Park Y, Ortiz J. A United Approach to Optimal Real and Reactive Power Dispatch. ACTA ACUST UNITED AC 1985. [DOI: 10.1109/tpas.1985.323466] [Citation(s) in RCA: 389] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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681
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Park Y, Lee K, O. Youn L. New Ananlytical Approach For Long-Term Generation Expansion Planning Based on Maximum Principle And Gaussian distribution Function. ACTA ACUST UNITED AC 1985. [DOI: 10.1109/tpas.1985.319054] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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682
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Stetler DA, Wrenshall LE, Park Y, Jacob ST. Induction of a distinct nuclear poly(A) polymerase and the production of anti-tumor poly(A) polymerase antibodies in hepatocarcinogenesis. Carcinogenesis 1984; 5:1363-6. [PMID: 6091938 DOI: 10.1093/carcin/5.10.1363] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Primary hepatomas induced in rats by an azo dye contained a distinct nuclear poly(A) polymerase which was different from the corresponding normal liver enzyme with respect to molecular weight and peptide map. The two enzymes could also be distinguished by their immunological characteristics. Sera from the carcinogen-fed rats contained antibodies to the tumor poly(A) polymerase even before the appearance of neoplastic nodules.
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683
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Abstract
Fifteen patients with metastatic breast cancer previously treated with chemotherapy were treated with a regimen consisting of vincristine, Adriamycin, and mitomycin. Eleven patients (73%) responded with three complete and eight partial responses. The median duration of response was eight months. While all four nonresponders died within five months, the median duration of survival of responders was 18 months. Toxicity was significant but tolerable. Thus, this preliminary report suggests that this regimen is active in advanced previously treated breast cancer, providing meaningful remissions with acceptable toxicity.
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684
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Nagata S, Nagae K, Park Y, Beppu S, Kawazoe K, Kito Y, Fujita T, Nimura Y, Sakakibara H. [Studies on vegetations in infective endocarditis with two-dimensional echocardiography]. JOURNAL OF CARDIOGRAPHY 1982; 12:869-74. [PMID: 7186008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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685
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Miyatake K, Okamoto M, Kinoshita N, Matsuhisa M, Nagata S, Beppu S, Park Y, Sakakibara H, Nimura Y. Pulmonary regurgitation studied with the ultrasonic pulsed Doppler technique. Circulation 1982; 65:969-76. [PMID: 7074762 DOI: 10.1161/01.cir.65.5.969] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Sixty patients with pulmonary regurgitation were studied by the pulsed Doppler technique combined with two-dimensional and M-mode echocardiography. Patients with pulmonary regurgitation had abnormal Doppler signals just below the pulmonic valve in the right ventricular outflow tract in diastole on the two-dimensional image. These signals were considered to indicate the regurgitant flow. There are two patterns of pulmonary regurgitant Doppler signals. In pulmonary hypertension, the maximal component of instantaneous flow velocity is sustained at about the same signal strength throughout diastole, but when the pulmonary arterial pressure is normal, the velocity slows down gradually from early diastole to end-diastole. Pulmonary regurgitation was detected by phonocardiography in about half the patients. In the remaining half, pulmonary regurgitant murmur could not be differentiated from aortic regurgitant murmur or was masked by coexistent aortic regurgitation or patent ductus arteriosus, whereas the Doppler technique indicated pulmonary regurgitation.
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686
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Abstract
A 67-year-old man with prostate cancer presented with acute polymyositis and vocal cord paralysis as a result of mediastinal lymphadenopathy. His clinical course was unusual, with the development of a malignant pleural effusion, supraclavicular adenopathy, and osteolytic bone lesions. Urologic symptoms developed only pre-terminally, and osteoblastic bone metastases were not documented. This case suggests that prostate cancer need not have a simple natural history.
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687
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Nimura Y, Beppu S, Nagata S, Park Y, Kinoshita N, Miyatake K, Okamoto M, Sakakibara H. [Ultrasonic imaging of idiopathic cardiomyopathies]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 1980; 38:2113-2123. [PMID: 6997557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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688
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Park Y, Mikolajcik EM. Effect of Temperature on Growth and Alpha Toxin Production by Clostridium perfringens 1. J Food Prot 1979; 42:848-851. [PMID: 30812208 DOI: 10.4315/0362-028x-42.11.848] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Growth and alpha toxin production by a strain of Clostridium perfringens was determined in Thioglycollate medium, beef broth with ground beef, and beef broth with ground beef and soy protein. Incubation temperatures ranged from 15 to 50 C. In Thioglycollate medium, maximum alpha toxin production occurred at 35 C and was 40 times greater than that observed at 45 C. However, generation time and maximum population were approximately the same at 35 and 45 C. At 15 C, a two log cycle reduction in viable counts occurred within 6 h. Irrespective of incubation temperature, alpha toxin levels in Thioglycollate medium declined as the incubation period was extended beyond the stationary growth phase. In the beef broth with ground beef system which was studied at 35 C only, the organism grew slower and produced less toxin than in Thioglycollate medium. The amount of alpha toxin detected was influenced to a greater extent by the incubation time and temperature, the holding time beyond the stationary growth phase, and the growth medium than by the population level of C. perfringens .
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689
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Nimura Y, Beppu S, Sakakibara H, Nagata S, Park Y. [Significance of real time ultrasonic cardiac tomography in morphological and dynamic analysis of the heart]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 1979; 37:139-47. [PMID: 430833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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690
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Park Y, Babajimopoulus M, Mikolajcik EM. Purification and Activity of Clostridium perfringens Alpha Toxin 1. J Food Prot 1977; 40:831-834. [PMID: 30736259 DOI: 10.4315/0362-028x-40.12.831] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Clostridium perfringens a-toxin obtained from a commercial source contained at least seven protein bands when examined by SDS polyacrylamide disc gel electrophoresis. The fraction with an Rm of 0.29-0.56 contained 95.6% of the total hemolytic activity and all of the phospholipolytic acitivity. The a-toxin when passed through a Sephadex G-100 column yielded several peaks but only one active fraction. This fraction upon electrophoresis in a SDS polyacrylamide disc gel system contained two protein bands. Only one protein with a Rm of 0.64 possessed hemolytic and phospholipolytic activites. A second passage of the active fraction through Sephadex G-100 yielded only one protein band. This protein exhibited both hemolytic and phospholipolytic activities. For C. perfringens , it is apparent that both of these activities reside with the same protein.
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691
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Park Y, Mikolajcik EM. Factors Affecting Quantification of Clostridium perfringens Alpha Toxin by the Hemolysin Indicator Plate Test and Other Procedures 1. J Food Prot 1977; 40:626-631. [PMID: 30736253 DOI: 10.4315/0362-028x-40.9.626] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Application of the following methods, electroimmunodiffusion on cellulose acetate, radial immunodiffusion, lecithovitellin agar plate, and hemolysin indicator plate, for quantification of alpha toxin of Clostridium perfringens revealed that the hemolysin indicator plate method was the most sensitive detecting 0.0003 unit/ml. Sensitivity of the hemolysin indicator plate method was enhanced 67-fold when alpha toxin was diluted with Brewer Thioglycollate medium (Difco, 0236) rather than physiological saline solution. The proteose-peptone ingredient of Thioglycollate medium was the major contributor to increased sensitivity. Less refined agar yielded a larger hemolytic zone. This was attributed, in part, to its higher calcium content. The reducing agent, sodium thioglycollate, diminished the hemolytic zone. In terms of clarity of hemolytic zone, the optimum human red blood cell concentration was 2.1 × 106/ml of base agar. Incubation of hemolytic indicator plates at 35 rather than 21 or 45 C yielded greater hemolytic zones. When incubation time was extended, hemolytic zones also increased in size.
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692
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Goedkin VL, Peng SM, Molin-Norris JA, Park Y. Carbon monoxide complexes of iron(II): synthesis and structural studies of five- and six-coordinate complexes of the macrocyclic ligand, C22H22N42. J Am Chem Soc 1976; 98:8391-8400. [PMID: 993530 DOI: 10.1021/ja00442a014] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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693
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Gall EP, Didizian NA, Park Y. Acute monarticular arthritis following patellar metastasis. A manifestation of carcinoma of the lung. JAMA 1974; 229:188-9. [PMID: 4406829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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