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Chang K. Swelling behavior and the release of protein from chitosan–pectin composite particles. Carbohydr Polym 2000. [DOI: 10.1016/s0144-8617(00)00145-4] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Orii R, Sugawara Y, Hayashida M, Yamada Y, Chang K, Takayama T, Makuuchi M, Hanaoka K. Effects of amrinone on ischaemia-reperfusion injury in cirrhotic patients undergoing hepatectomy: a comparative study with prostaglandin E1. Br J Anaesth 2000; 85:389-95. [PMID: 11103179 DOI: 10.1093/bja/85.3.389] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The effects of amrinone, a selective phosphodiesterase III inhibitor, on liver ischaemia reperfusion injury have not yet been clarified. Forty-five patients with hepatocellular carcinoma who underwent partial liver resection using Pringle's manoeuvre were studied. Patients were divided into three groups: those given amrinone, those given prostaglandin E1 (PGE1) and those not treated (controls). An indocyanine green (ICG) clearance test was performed before the operation and three times during surgery: just before induction of liver ischaemia, just after liver resection and 60 min after reperfusion. Blood lactate and base excess were measured at the same times. Systolic and diastolic arterial pressure, heart rate, cardiac index and oesophageal temperature were monitored. Aminotransferase levels were recorded the day before surgery, 1 h after operation and on the first and third postoperative days. These data were compared between groups. The ICG elimination rate, lactate and base excess in the amrinone group differed significantly from those in controls during the observation period (P = 0.03, P = 0.04 and P = 0.03, respectively). The differences between the PGE1 and control groups were not significant. There were no significant differences between the groups in perioperative vital signs, cardiac index or postoperative aminotransferase. Amrinone enhanced intraoperative ICG elimination in cirrhotic patients who underwent liver resection.
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Alsolaiman MM, Chang K, Arjomand H, Oza R, Costacurta G. Acute left anterior descending artery occlusion in a hemophiliac A patient during recombinant factor VIII infusion: treatment with coronary angioplasty. Catheter Cardiovasc Interv 2000; 50:468-72. [PMID: 10931624 DOI: 10.1002/1522-726x(200008)50:4<468::aid-ccd22>3.0.co;2-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Acute myocardial infarction in association with the replacement of recombinant factor VIII in hemophiliacs has not been documented. We describe the use of PTCA in a hemophiliac A patient who developed acute myocardial infarction during factor VIII replacement. Because surgery in hemophiliac A patients remains hazardous, PTCA seems to be an attractive alternative.
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Tamai H, Masago K, Chang K, Iwamura N, Ohkado S, Uchida K, Ohtsuji M, Chinzei M, Hanaoka K. [Anesthetic management for neonates with congenital cystic adenomatoid malformation]. MASUI. THE JAPANESE JOURNAL OF ANESTHESIOLOGY 2000; 49:750-4. [PMID: 10933026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
We experienced two cases of congenital cystic adenomatoid malformation (CCAM) diagnosed by prenatal ultrasonography. The first case with type I CCAM underwent the resection of the right upper lobe 8 days after birth. Postoperative course was uneventful. The second case with type III CCAM developed non-immune hydrops, severe mediastinal shift, and polyhydroamnios at 29 weeks' gestation. At 30 weeks' gestation, cesarean section was performed. Immediately after birth, the resection of lung tumor for the neonate was performed. However, the neonate died on the 1st postoperative day.
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Chun M, Kang S, Ryu H, Chang K, Oh Y, Ju H, Lee E. Modified partial hyperfractionation in radiotherapy for bulky uterine cervical cancer: reduction of overall treatment time. Int J Radiat Oncol Biol Phys 2000; 47:973-7. [PMID: 10863067 DOI: 10.1016/s0360-3016(00)00539-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE The purpose of this study was to assess the feasibility and toxicity of modified fractionation of external beam radiation with the intention of reducing the overall treatment time (OT) by 1 week in cervical cancer. METHODS AND MATERIALS Thirty-one patients (Group 1, n = 31) with bulky cervical cancer (>/= 4 cm with Stage II and III, >/= 5 cm with Stage IB2) were entered into the twice a day (b.i. d.) protocol (18 Gy/10 fx in 2 weeks followed by 18 Gy/12 fx, b.i.d. in 6 days, then midline block at 36 Gy with 45 Gy to the whole pelvis and 51-59 Gy to the parametrium). These patients underwent high-dose-rate brachytherapy with 4 Gy/fx x 7 to point A, biweekly. During the same period, patients with non-bulky tumors (Group 2, n = 31) received conventional treatment and similar brachytherapy. RESULTS The OT of Group 1 was 7 weeks or less in 61.3%, 7.1-8 weeks in 29%, and more than 8 weeks in 9.7% (19.4%, 51.6%, and 29% in Group 2, respectively, p = 0.003). Incidences of acute complications and treatment breaks were similar in both groups. Late complication (rectal bleeding) occurred only in Group 1 (13%, 4/31), but was self-limited. Locoregional failures occurred within 2 years after completion of radiation therapy in both groups (16% and 13% in Group 1 and 2, respectively, with minimum and median follow-ups of 2 years and 34 months). CONCLUSION Partial hyperfractionation on the third week of radiation permitted patients to finish their treatment with shorter OT without excessive acute complications and with acceptable grade 2 late rectal bleeding complications. This treatment scheme may be an effective method for the improvement of local control of bulky cervical cancer.
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Park CH, Choi SH, Piao Y, Kim S, Lee YJ, Kim HS, Jeong SJ, Rah JC, Seo JH, Lee JH, Chang K, Jung YJ, Suh YH. Glutamate and aspartate impair memory retention and damage hypothalamic neurons in adult mice. Toxicol Lett 2000; 115:117-25. [PMID: 10802387 DOI: 10.1016/s0378-4274(00)00188-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We examined the effects of systemic administration of monosodium glutamate (MSG) or aspartate (ASP) on the memory retention and neuronal damage in the brains of adult mice. Compared with the control mice, a single intraperitoneal injection of either 4.0 mg/g MSG or 0.5 mg/g ASP after acquisition trial significantly shortened the response latency in the passive avoidance test, accompanying by the transient weight loss. Histopathological analysis of the brains of these mice revealed that neurons in the arcuate nucleus of hypothalamus were damaged markedly by MSG (4.0 mg/g) or ASP (0.5 mg/g). Other brain areas including cerebral cortex and hippocampus did not show any pathological changes. These findings suggest that systemic administration of MSG or ASP could impair memory retention and damage hypothalamic neurons in adult mice.
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Ryu KH, Rhee HI, Jung I, Kim TS, Lee SJ, Im GJ, Lee N, Ryu DH, Kim YW, Kim JJ, Chang K, Lee BH, Shin HS, Kim EJ, Kim KH, Kim DK. General pharmacology of the new antiviral agent SK 1899. ARZNEIMITTEL-FORSCHUNG 2000; 50:395-403. [PMID: 10800640 DOI: 10.1055/s-0031-1300220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The general pharmacological properties of 2-amino-9-(3-acetoxymethyl-4-isopropoxycarbonyloxybut-1-yl)purine (CAS 247081-81-8, SK 1899), a new potential antiviral agent, were investigated in mice, rats, guinea pigs, rabbits, and dogs. The oral administration of 50, 150, and 500 mg/kg of SK 1899 had no effects on the central nervous system except that it slightly increased the spontaneous locomotor activity in mice at a dose of 500 mg/kg. SK 1899 did not disturb either the spontaneous motility or contractor-induced contraction of the isolated organs such as guinea pig ileum, rat uterus, guinea pig vas deferens, and guinea pig trachea at concentrations up to 10(-4) mol/l. It slightly increased the contractile force in the isolated guinea pig atrium at a concentration of 10(-4) mol/l. Following intravenous infusion of 5, 15, and 50 mg/kg of SK 1899 to anesthetized dogs, it did not change the mean arterial pressure, heart rate, left ventricular systolic pressure (LVSP), and respiratory rate, while it slightly increased the left ventricular positive dP/dtmax (LV + dP/dtmax) at a dose of 50 mg/kg. SK 1899 did not induce any significant changes in the intestinal charcoal meal transit in mice, basal gastric juice secretion in rats, and renal function in rats. It did not affect the blood coagulation system and phenolsulfonphthalein secretion in rats. These findings suggest that SK 1899 has a very low potential to induce any adverse pharmacological effects at the doses showing antiviral activity.
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Ruan R, Chen P, Chang K, Kim HJ, Taub I. Rapid Food Particle Temperature Mapping During Ohmic Heating Using FLASH MRI. J Food Sci 1999. [DOI: 10.1111/j.1365-2621.1999.tb12273.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Veitch PC, Ogle SJ, Chang K. How best to fix a broken hip. Med J Aust 1999; 171:330; author reply 330-1. [PMID: 10560453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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Kim DK, Lee N, Ryu DH, Kim YW, Kim JS, Chang K, Im GJ, Choi WS, Cho YB, Kim KH, Colledge D, Locarnini S. Synthesis and evaluation of 2-amino-9-(3-acyloxymethyl-4-alkoxycarbonyloxybut-1-yl)purines and 2-amino-9-(3-alkoxycarbonyloxymethyl-4-alkoxycarbonyloxybut-1- yl)purines as potential prodrugs of penciclovir. Bioorg Med Chem 1999; 7:1715-25. [PMID: 10482463 DOI: 10.1016/s0968-0896(99)00086-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A series of 2-amino-9-(3-acyloxymethyl-4-alkoxycarbonyloxybut-1-yl)purin es (1-8) and 2-amino-9-(3-alkoxycarbonyl-oxymethyl-4-alkoxycarbonyloxybut -1-yl)purines (9-12) were synthesized as potential prodrugs of penciclovir. Treatment of 6-deoxypenciclovir with trimethyl orthoacetate or triethyl orthopropionate (1.2 equiv) in DMF in the presence of p-TsOH.H2O (0.1 equiv) followed by quenching with excess H2O gave the corresponding mono-O-acetyl or mono-O-propionyl compound, 17 or 18, in excellent yields of 95 and 92%, respectively. Reactions of 17 or 18 with an appropriate alkyl (Me, Et, n-Pr, and i-Pr) 4-nitrophenyl carbonate (1.2 equiv) in pyridine in the presence of a catalytic amount of DMAP (0.1 equiv) at 80 degrees C afforded the monoacyl, monocarbonate derivatives of 6-deoxypenciclovir, 1-8, in 86 94% yields. Similar reactions of 6-deoxypenciclovir with 2.1 equiv of alkyl 4-nitrophenyl carbonate produced the dicarbonate derivatives 9 12 in 81-83% yields. Of the prodrugs tested in rats, 2-amino-9-(3-acetoxymethyl-4-isopropoxycarbonyloxybut-1-yl)purine (4) achieved the highest mean urinary recovery of penciclovir (36%), followed in order by compounds 2 (35%), 6 (35%), 7 (34%), 10 (34%), 8 (32%), 3 (32%), and famciclovir (31%). The mean urinary recovery of penciclovir and concentrations of penciclovir in the blood from 4 in mice were also slightly higher than those from famciclovir. The in vivo antiviral efficacy of 4 in HSV-1-infected normal BALB/c mice was higher than those of famciclovir and valaciclovir in terms of mortality (100, 80, and 40%) and mean survival time ( > 21, 13+/-5.0 (SEM), and 13+/-1.6 days). Compound 4 demonstrated an effective anti-hepadnaviral response with intrahepatic viral load being reduced by 90%, the viral supercoiled DNA levels reduced by 70% and Pre-S expression inhibited by 30% against duck hepatitis B virus (DHBV) in vivo, and did not cause any significant hepatotoxicity after 4 weeks of treatment.
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Cobb JP, Hotchkiss RS, Swanson PE, Chang K, Qiu Y, Laubach VE, Karl IE, Buchman TG. Inducible nitric oxide synthase (iNOS) gene deficiency increases the mortality of sepsis in mice. Surgery 1999; 126:438-42. [PMID: 10455918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
BACKGROUND Nitric oxide (NO) produced by the inducible isoform of NO synthase (iNOS or NOS2) has been implicated in the hypotension, organ failure, and death that complicate sepsis. To avoid the confounding effects and limitations of iNOS inhibitors, we used iNOS gene "knockout" mice to examine the effect of inducible NO production in a model of polymicrobial abdominal sepsis treated with antibiotics. We hypothesized that iNOS gene deficiency would significantly alter outcome. METHODS C57BL6 wild-type (control) and congenic iNOS knockout mice were studied concurrently. Under halothane anesthesia, the ceca were ligated with 4-0 silk suture and punctured twice with a 26-gauge needle (cecal ligation and puncture, CLP). Survival was followed for 7 days, after which necropsies were performed in surviving animals. In an accompanying study examining the acute effects of sepsis, organ injury at 18 hours after CLP as determined by histology and the degree of cell death by apoptosis were examined with the use of hematoxylin and eosin (H&E) and TUNEL staining and two-channel fluorescence-activated cell sorter (FACS) analysis. RESULTS Sham laparotomy produced no lethality in either knockout (n = 3) or wild-type (n = 3) animals. Compared with survival in controls (n = 20), survival after CLP in iNOS knockout mice (n = 21) was significantly decreased (P < .01 at 2 days, P = .080 at 7 days, Mantel-Haenszel log-rank test). CLP-induced apoptotic cell death was significantly less in the thymus of iNOS knockout mice compared with wild-type mice. CONCLUSIONS We conclude that iNOS gene function provides a survival benefit in septic mice and is associated with increased sepsis-induced thymocyte apoptosis. To our knowledge, this is the first survival study examining the effect of iNOS gene deficiency in a clinically relevant model of sepsis.
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Chang K, Sauereisen S, Dlutowski M, Veloski JJ, Nash DB. A cost-effective method to characterize variation in clinical practice. Eval Health Prof 1999; 22:184-96. [PMID: 10557854 DOI: 10.1177/01632789922034257] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This study's objective was to measure variation in physicians' practice styles and policies. Family physicians and general internists were surveyed about evidence-based medicine in the areas of asthma, congestive heart failure, and diabetes mellitus. They were asked about clinical recommendations where standards of practice were uncertain, controversial, or changing in response to published guidelines. Also included were items dealing with managed care. Although there was wide variation in responses to 20 of 36 items, some responses were consistent with practice guidelines. Responses to several items indicated a tendency to overuse expensive tests. Overall, the results indicate that a brief, open-ended survey can assess practice variation quickly and economically, as contrasted with more expensive analyses of medical records or claims data. With proper validation such assessments can be used as baselines to guide interventions, as well as measures of the outcomes of these interventions to change practice styles.
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Simonini A, Chang K, Yue P, Long CS, Massie BM. Expression of skeletal muscle sarcoplasmic reticulum calcium-ATPase is reduced in rats with postinfarction heart failure. HEART (BRITISH CARDIAC SOCIETY) 1999; 81:303-7. [PMID: 10026358 PMCID: PMC1728966 DOI: 10.1136/hrt.81.3.303] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To determine whether heart failure in rats is associated with altered expression of the skeletal muscle sarcoplasmic reticulum Ca2+-ATPase (SERCA). METHODS SERCA protein and mRNA were examined in the soleus muscles of eight female rats with heart failure induced by coronary artery ligation, six weeks after the procedure (mean (SEM) left ventricular end diastolic pressure 20.4 (2.2) mm Hg) and in six sham operated controls by western and northern analyses, respectively. RESULTS SERCA-2a isoform protein was reduced by 16% (112 000 (4000) v 134 000 (2000) arbitrary units, p < 0.001), and SERCA-2a messenger RNA was reduced by 59% (0.24 (0. 06) v 0.58 (0.02) arbitrary units, p < 0.001). Although rats with heart failure had smaller muscles (0.54 mg/g v 0.66 mg/g body weight), no difference in locomotor activity was observed. CONCLUSIONS These results may explain the previously documented abnormalities in calcium handling in skeletal muscle from animals with the same model of congestive heart failure, and could be responsible for the accelerated muscle fatigue characteristic of patients with heart failure.
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Haskell-Luevano C, Chen P, Li C, Chang K, Smith MS, Cameron JL, Cone RD. Characterization of the neuroanatomical distribution of agouti-related protein immunoreactivity in the rhesus monkey and the rat. Endocrinology 1999; 140:1408-15. [PMID: 10067869 DOI: 10.1210/endo.140.3.6544] [Citation(s) in RCA: 142] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Agouti-related protein (AGRP) is a recently described homolog of the skin agouti protein. AGRP is transcribed primarily in the adrenal and hypothalamus and is a high affinity antagonist of the neural melanocortin-3 and melanocortin-4 receptors. The perikarya expressing AGRP messenger RNA are found in the arcuate nucleus of the rat and rhesus monkey. Using a polyclonal antibody against the pharmacologically active domain of AGRP (amino acids 83-132), we have also characterized the distribution of AGRP-immunoreactive neurons in both species. The major fiber tracts are conserved in both species, with dense projections originating in the arcuate nucleus and proceeding along the third ventricle. Dense fiber bundles are also visible in the paraventricular, dorsomedial, and posterior nuclei in the hypothalamus, in the bed nucleus of the stria terminalis, and in the lateral septal nucleus of the septal region. AGRP-containing neurons are not visualized in a number of areas, including portions of the amygdala, thalamus, and brain stem, that express MC3-R and MC4-R messenger RNA and receive innervation from POMC neurons that serve as the source of melanocortin agonists. Thus, AGRP is most likely to be involved in modulating a conserved subset of the physiological functions of central melanocortin peptides. Based on the particular distribution of AGRP neurons, those functions are likely to include the central control of energy homeostasis.
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Kim JS, Chae MR, Chang K, Park KH, Rho HW, Park BH, Park JW, Kim HR. Cytotoxicity of Vibrio vulnificus cytolysin on rat peritoneal mast cells. Microbiol Immunol 1999; 42:837-43. [PMID: 10037218 DOI: 10.1111/j.1348-0421.1998.tb02359.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Histamine has been thought to be a permeability enhancing factor in Vibrio vulnificus infection. The injection of living bacteria or purified V. vulnificus cytolysin (VVC) can cause lethality in mice by inducing hemoconcentration and increased vascular permeability. In the present study, we tried to identify whether histamine release causes the increased vascular permeability that is responsible for the lethal effect of VVC. Treatment of rat peritoneal mast cells with high concentrations of VVC caused the release of whole cellular histamine and lactate dehydrogenase (LDH). At concentrations less than 10 HU/ml, histamine and LDH were not released whereas preloaded 2-deoxy-D-glucose was rapidly effluxed with the concomitant decrease in cellular ATP. VVC-treated mast cells were refractory to the stimulation of histamine secretion by Compound 48/80 but remained fully responsive to Ca2+ plus GTP-gamma-S. These results indicate that histamine can be released from mast cells only when the concentration of VVC is high enough to cause the lysis of cells. At low concentrations, VVC does not induce the release of stored histamine from damaged cells. The intravenous injection of 80 HU purified VVC to rats, which can produce the calculated blood concentration of about 3 HU/ml, caused a marked increase in pulmonary vascular permeability, hemoconcentration and death. However, no increase in blood histamine level was detected. This level of VVC in rat blood was enough to cause severe hemoconcentration and lethality but might not be enough to cause cytolysis of the mast cells and resulting histamine release.
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Kim DK, Lee N, Kim YW, Chang K, Im GJ, Choi WS, Kim KH. Synthesis and evaluation of amino acid esters of 6-deoxypenciclovir as potential prodrugs of penciclovir. Bioorg Med Chem 1999; 7:419-24. [PMID: 10218837 DOI: 10.1016/s0968-0896(98)00235-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The amino acid ester derivatives of 6-deoxypenciclovir, 11-20, were synthesized as potential prodrugs of penciclovir, and were evaluated for their oral penciclovir bioavailability in mice and rats. Esterification of 6-deoxypenciclovir with N-carbobenzyl-oxyglycine, -L-alanine, -L-valine, -L-leucine, or -L-isoleucine (3.75equiv.) using conventional coupling method (DCC/DMAP) afforded the mono-O-ester derivatives 1-5 in 47-55% yields as a mixture of two diastereomers along with the di-O-ester derivatives 6-10 in 20-29% yields. Reductive cleavage of carbobenzyloxy (Cbz) group (10% Pd/C, 1 atmosphere of H2, room temperature in methanol) followed by subsequent treatment of the resulting free amine with methanolic HCI solution provided the mono-O-ester derivatives 11-15 as di-HCl salt in 51-98% yields and the di-O-ester derivatives 16-20 as tri-HCl salt in 65 98% yields. Of the prodrugs tested in mice and rats, 6-deoxypenciclovir O-L-valinate (13), O-L-isoleucinate (15), and O,O-di-glycinate (16) showed significantly higher urinary recovery of penciclovir compared with that of penciclovir, but those are somewhat lower than that of famciclovir.
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Kim DK, Chang K, Im GJ, Kim HT, Lee N, Kim KH. Synthesis and evaluation of 2-amino-9-(1, 3-dihydroxy-2-propoxymethyl)- 6-fluoropurine mono- and diesters as potential prodrugs of ganciclovir. J Med Chem 1999; 42:324-8. [PMID: 9925738 DOI: 10.1021/jm980321+] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of 2-amino-9-(1,3-dihydroxy-2-propoxymethyl)-6-fluoropurine mono- and diesters, 6a-h, were synthesized as potential prodrugs of ganciclovir and evaluated for their oral ganciclovir bioavailability in rats. Treatment of 2-amino-6-chloro-9-(1, 3-dihydroxy-2-propoxymethyl)purine (4) with Me3N in DMF/THF (1/4) followed by the reaction of the resulting trimethylammonium chloride salt 5 with KF in DMF gave 2-amino-9-(1, 3-dihydroxy-2-propoxymethyl)-6-fluoropurine (2) in 83% yield. Esterification of 2 with an appropriate acid anhydride (Ac2O, (EtCO)2O, (n-PrCO)2O, or (i-PrCO)2O) (6 equiv for 6a-d or 1 equiv for 6e-h) in DMF in the presence of a catalytic amount of DMAP produced the diesters 6a-d in 92-98% yields and the monoesters 6e-h in 37-44% yields. Of the prodrugs tested in rats, the monoisobutyrate 6h achieved the highest ganciclovir bioavailability (45%) that is 15-fold higher than that from ganciclovir (3%), followed in order by the diisobutyrate 6d (42%), the diacetate 6a (41%), the monobutyrate 6g (41%), the monopropionate 6f (39%), the dipropionate 6b (35%), the dibutyrate 6c (35%), and the monoacetate 6e (29%). The prodrugs 6e-h were found to be quite stable at pH 6.0 (t1/2 = >29 days), 7.4 (t1/2 = >7 days), and 8.0 (t1/2 = >2 days) but had relatively short half-lives at pH 1.2 (t1/2 = 60-83 min).
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Wong D, Chou S, Chang K. Establishment and characterization of a cell line (ME) derived from a human oral melanoma. Int J Oral Maxillofac Surg 1999. [DOI: 10.1016/s0901-5027(99)81007-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Okamoto H, Takuwa N, Gonda K, Okazaki H, Chang K, Yatomi Y, Shigematsu H, Takuwa Y. EDG1 is a functional sphingosine-1-phosphate receptor that is linked via a Gi/o to multiple signaling pathways, including phospholipase C activation, Ca2+ mobilization, Ras-mitogen-activated protein kinase activation, and adenylate cyclase inhibition. J Biol Chem 1998; 273:27104-10. [PMID: 9765227 DOI: 10.1074/jbc.273.42.27104] [Citation(s) in RCA: 218] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In Chinese hamster ovary (CHO) cells transiently transfected with an expression vector for EDG1, but not an empty vector, sphingosine-1-phosphate (SP) at a concentration as low as 10(-10) M caused an increase in the intracellular free Ca2+ concentration ([Ca2+]i) as a result of mobilization of Ca2+ from both intracellular and extracellular pools. In a CHO clone stably expressing EDG1 receptor (CHO-EDG1 cells), SP induced increases in the production of inositol phosphates and the [Ca2+]i and inhibited forskolin-induced increase in the cellular cAMP content, all in a manner sensitive to pertussis toxin. SP also activated mitogen-activated protein kinase in CHO-EDG1 cells in pertussis toxin-sensitive and Ras-dependent manners. To evaluate the spectrum of agonists for EDG1, we used human erythroleukemia (HEL) cells, which at naive state do not respond to SP or structurally related lipids with an increase in the [Ca2+]i. In HEL cells stably expressing EDG1 receptor (HEL-EDG1 cells), SP dose-dependently increased the [Ca2+]i with half-maximal and maximal concentration values of 10(-9) and 3 x 10(-7) M, respectively; sphingosylphosphorylcholine at exclusively high concentrations, but not sphingosine at all, also increased the [Ca2+]i. HEL-EDG1 cells bound 32P-labeled SP, which was displaced dose dependently by unlabeled SP. These results indicate that EDG1, a member of the EDG family G protein-coupled receptors, is a specific, high-affinity SP receptor.
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Kim DK, Lee N, Kim YW, Chang K, Kim JS, Im GJ, Choi WS, Jung I, Kim TS, Hwang YY, Min DS, Um KA, Cho YB, Kim KH. Synthesis and evaluation of 2-amino-9-(3-hydroxymethyl-4-alkoxycarbonyloxybut-1-yl)purines as potential prodrugs of penciclovir. J Med Chem 1998; 41:3435-41. [PMID: 9719596 DOI: 10.1021/jm980138g] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A series of 2-amino-9-(3-hydroxymethyl-4-alkoxycarbonyloxybut-1-yl)purines (4-10) and 2-amino-9-(2-(2-oxo-1,3-dioxan-5-yl)ethyl)purine (1) were synthesized as potential prodrugs of penciclovir and evaluated for their oral penciclovir bioavailability in mice and rats. Treatment of 2-(2-benzyloxyethyl)propane-1,3-diol (11) with 1,1'-carbonyldiimidazole in THF followed by hydrogenolytic removal of the benzyl group of the resulting cyclic carbonate 12 gave 5-(2-hydroxyethyl)-1,3-dioxan-2-one (13). Mesylation of the alcohol 13 and then a coupling reaction of the resulting mesylate 14 with 2-amino-6-chloropurine using anhydrous Cs2CO3 in DMF afforded 2-amino-6-chloro-9-(2-(2-oxo-1,3-dioxan-5-yl)ethyl)purine (16) after purification by flash column chromatography on silica gel using EtOAc/MeCN/Et3N as eluent. Hydrogenation of the 6-chloro cyclic carbonate 16 followed by a ring-opening reaction of the 6-deoxy cyclic carbonate 1 in a mixture of an appropriate alcohol and CHCl3 using activated SiO2 as a Lewis acid afforded the corresponding alkyl monocarbonate derivatives 3-10 in fair to good yields. Of the prodrugs tested in mice, the isopropyl monocarbonate 6 achieved the highest mean urinary recovery of penciclovir (53%), followed in order by the propyl monocarbonate 5 (51%), the isopentyl monocarbonate 10 (51%), the ethyl monocarbonate 4 (50%), and famciclovir (48%). In rats, the methyl monocarbonate 3, 4, 6, the n-butyl monocarbonate 7, and 10 (39-41%) showed levels of mean urinary recovery of penciclovir similar to that from famciclovir (40%). The alkyl monocarbonates 4-10 were found to be quite stable in the aqueous buffer solutions, and among them, 6 was the most stable with the half-lives (t1/2) of 88, >200, 61, and 26 days at pH 1.2, 6.0, 7.4, and 8.0, respectively. In addition, 6 was highly soluble in H2O (138.8 mg/mL, 20 degrees C).
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Abstract
Disease management is a systematic approach to a health condition or a healthcare intervention that organises preventative, interventional and care approaches throughout the continuum of care and which measures outcomes in terms of populations, not individuals. Disease management's advantage over the current component system is that it stresses prevention over acute treatment of a chronic disease. Patients with better control of their chronic diseases will likely have a decrease in the use of emergency room and inpatient hospitalisation services, thereby improving clinical outcomes of patients. To achieve these goals, disease management uses pharmacoeconomic evaluations and outcomes measures to provide information that helps build formularies and clinical practice guidelines. Several problems exist in integrating pharmacoeconomic studies in disease management models, such as the need for more integrated information systems, standardisation and who should perform these evaluations. Some possible solutions will be addressed in this article. With greater emphasis being placed on controlling costs, the need for pharmacoeconomic evaluations in the design of disease management models will continue to increase in the future.
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Abstract
There is increasing demand for measurement tools to assess health related quality of life among the Chinese elderly population in the United States. Health services questionnaires, developed largely in English, often under-represent Chinese Americans. Based on conventional mortality statistics, the public mistakenly views Chinese Americans as a "model" minority with no health problems. This general perception has masked the serious health problems among the elderly Chinese Americans. Using the newly developed Chinese version of the MOS SF-36, we aim to explore how elderly Chinese perceive their own health. Based on 219 elderly Chinese recruited in Boston, the study provided mixed results with regard to the perception of a healthy minority model. While the study subjects perceived similar or better physical health to the U.S. norm, they reported worse mental health than the U.S. norm. We explored possible explanations for this discrepancy and discussed the implications as well as directions for future research.
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174
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Soetikno RM, Chang K. Endoscopic ultrasound-guided diagnosis and therapy in pancreatic disease. Gastrointest Endosc Clin N Am 1998; 8:237-47. [PMID: 9405760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The role of endoscopic ultrasound (EUS) in the detection and staging of pancreatic cancer is well established in medical literature. The development of EUS-guided fine needle aspiration (FNA) and subsequently EUS-guided fine needle injection (FNI) has expanded the clinical utility of EUS. These newer techniques made "interventional" EUS possible. Several recent applications of EUS-guided FNI include celiac nerve block, pseudocyst drainage, and drug delivery into pancreatic tumors. EUS is also gaining acceptance as an alternative diagnostic modality in the management of choledocholithiasis. The value of EUS in the diagnosis of early chronic pancreatitis is still being actively studied. This article reviews a number of recent developments in EUS-guided diagnosis and therapy with an emphasis on EUS-guided FNA and EUS-guided FNI.
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175
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Heath M, Bowyer K, Kopans D, Kegelmeyer P, Moore R, Chang K, Munishkumaran S. Current Status of the Digital Database for Screening Mammography. COMPUTATIONAL IMAGING AND VISION 1998. [DOI: 10.1007/978-94-011-5318-8_75] [Citation(s) in RCA: 284] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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176
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Ruan R, Chang K, Chen P, Fulcher R, Bastian E. A Magnetic Resonance Imaging Technique for Quantitative Mapping of Moisture and Fat in a Cheese Block. J Dairy Sci 1998. [DOI: 10.3168/jds.s0022-0302(98)75544-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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177
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Morgan RJ, Doroshow JH, Venkataraman K, Chang K, Raschko J, Somlo G, Leong L, Tetef M, Shibata S, Hamasaki V, Margolin K, Forman S, Akman S, Coluzzi P, Ahn C, Weiss L, Gadgil U, Harrison J. High-dose infusional doxorubicin and cyclophosphamide: a feasibility study of tandem high-dose chemotherapy cycles without stem cell support. Clin Cancer Res 1997; 3:2337-45. [PMID: 9815632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The purpose of this study was to determine the maximally tolerated dose of doxorubicin administered during two cycles of intensive chemotherapy with cyclophosphamide and doxorubicin without stem cell support in patients with advanced cancer and to assess the cumulative cardiac toxicity of the regimen by noninvasive radionuclide imaging and by pre-and postchemotherapy endomyocardial biopsies. Thirty-eight patients (thirty-six with high risk or metastatic breast cancer) were treated in a dose-escalation trial using a fixed dose of i.v. cyclophosphamide (4.2 g/m2) administered over 2 h on day 5 and escalating doses of doxorubicin (50-175 mg/m2) given as a 96-h continuous i.v. infusion on days 1-4, using Filgrastim (granulocyte colony-stimulating factor) for hematological support beginning on day 6. All patients underwent pretreatment, and 28 patients underwent postchemotherapy endomyocardial biopsies. Twenty-nine of 38 patients received two cycles of treatment (median number of days between cycles, 44; range, 34-62). Twenty-one patients had received doxorubicin previously at cumulative dose levels </=150 mg/m2; all patients had pretreatment endomyocardial biopsy scores less than 1. One patient treated at the highest dose level of doxorubicin (175 mg/m2) developed symptoms of mild congestive heart failure following two cycles of chemotherapy. Pre- and posttreatment radionuclide ejection fractions were 65 and 45%, respectively; this patient had a posttreatment endomyocardial biopsy score of 1 (damage to <5% of myocytes). One additional patient at this dose level had an asymptomatic biopsy score of 1, with a decrease in ejection fraction from 62 to 43%; this recovered to 58% 5 months after completion of chemotherapy. Six additional patients treated at lower dose levels had abnormal posttreatment endomyocardial biopsies without abnormal posttreatment ejection fractions. Nine patients received only one cycle of chemotherapy: five patients due to decreased cardiac ejection fraction following cycle 1 (two of these patients had normal endomyocardial biopsies, and two patients had biopsy scores of 1); one patient secondary to tumor progression following cycle one; one patient due to persistently detectable Clostridium difficile toxin in the stool; one patient refused cycle two; and one patient died following cycle one of complications related to sepsis. A single patient experienced a grand mal seizure associated with orthostatic hypotension, which was considered the dose-limiting toxicity. The median duration (over two cycles) of granulocytopenia (absolute granulocyte count <500/microliter) at the maximally tolerated dose level of 150 mg/m2 was 8.5 days (range, 5-13 days), and the median duration of thrombocytopenia (platelets <20,000/microliter) was 2.5 days (range, 0-9 days). The median duration of hospitalization including chemotherapy administration was 23 days (range, 19-36 days). Other toxicities included stomatitis, fever, diarrhea, and emesis. One patient developed acute leukemia 54 months posttreatment. We conclude that two courses of high-dose cyclophosphamide and doxorubicin using granulocyte colony-stimulating factor are feasible and safe with tolerable myocardial toxicity as evidenced by serial endomyocardial biopsies. The dose-limiting toxicity encountered was a grand mal seizure. The recommended Phase II dose is doxorubicin 150 mg/m2 administered as a 96-h infusion on days 1-4, with cyclophosphamide 4. 2 g/m2 on day 5 and G-CSF 5 microgram/kg/day started on day 6 and administered until the total WBC is above 10,000/microliter for three consecutive days.
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Worrall NK, Chang K, LeJeune WS, Misko TP, Sullivan PM, Ferguson TB, Williamson JR. TNF-alpha causes reversible in vivo systemic vascular barrier dysfunction via NO-dependent and -independent mechanisms. THE AMERICAN JOURNAL OF PHYSIOLOGY 1997; 273:H2565-74. [PMID: 9435588 DOI: 10.1152/ajpheart.1997.273.6.h2565] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Tumor necrosis factor (TNF-alpha) and nitric oxide (NO) are important vasoactive mediators of septic shock. This study used a well-characterized quantitative permeation method to examine the effect of TNF-alpha and NO on systemic vascular barrier function in vivo, without confounding endotoxemia, hypotension, or organ damage. Our results showed 1) TNF-alpha reversibly increased albumin permeation in the systemic vasculature (e.g., lung, liver, brain, etc.); 2) TNF-alpha did not affect hemodynamics or blood flow or cause significant tissue injury; 3) pulmonary vascular barrier dysfunction was associated with increased lung water content and impaired oxygenation; 4) TNF-alpha caused inducible nitric oxide synthase (iNOS) mRNA expression in the lung and increased in vivo NO production; 5) selective inhibition of iNOS with aminoguanidine prevented TNF-alpha-induced lung and liver vascular barrier dysfunction; 6) aminoguanidine prevented increased tissue water content in TNF-alpha-treated lungs and improved oxygenation; and 7) nonselective inhibition of NOS with NG-monomethly-L-arginine increased vascular permeation in control lungs and caused severe lung injury in TNF-alpha-treated animals. We conclude that 1) TNF-alpha reversibly impairs vascular barrier integrity through NO-dependent and -independent mechanisms; 2) nonselective NOS inhibition increased vascular barrier dysfunction and caused severe lung injury, whereas selective inhibition of iNOS prevented impaired endothelial barrier integrity and pulmonary dysfunction; and 3) selective inhibition of iNOS may be beneficial in treating increased vascular permeability that complicates endotoxemia and cytokine immunotherapy.
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179
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Chang K. Dimensions and indicators of patients' perceived nursing care quality in the hospital setting. J Nurs Care Qual 1997; 11:26-37. [PMID: 9267117 DOI: 10.1097/00001786-199708000-00005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Nursing professionals have noted the impact of cost-containment strategies on nursing care quality in the hospital setting. However, there is a lack of scientific data to demonstrate the impact. The author reviewed 53 published data-based primary studies of patient satisfaction with nursing care (PSNC) from 1982 to the present and identified 13 published PSNC instruments. The author performed content analysis of the published instruments and identified the dimensions and indicators of patients' perceived structure, process, and outcomes attributed to nursing care. The needs for further development of instruments to assess patients' perceived nursing care quality are identified.
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180
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Ido Y, Vindigni A, Chang K, Stramm L, Chance R, Heath WF, DiMarchi RD, Di Cera E, Williamson JR. Prevention of vascular and neural dysfunction in diabetic rats by C-peptide. Science 1997; 277:563-6. [PMID: 9228006 DOI: 10.1126/science.277.5325.563] [Citation(s) in RCA: 223] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
C-peptide, a cleavage product from the processing of proinsulin to insulin, has been considered to possess little if any biological activity other than its participation in insulin synthesis. Injection of human C-peptide prevented or attenuated vascular and neural (electrophysiological) dysfunction and impaired Na+- and K+-dependent adenosine triphosphate activity in tissues of diabetic rats. Nonpolar amino acids in the midportion of the peptide were required for these biological effects. Synthetic reverse sequence (retro) and all-D-amino acid (enantio) C-peptides were equipotent to native C-peptide, which indicates that the effects of C-peptide on diabetic vascular and neural dysfunction were mediated by nonchiral interactions instead of stereospecific receptors or binding sites.
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181
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Ido Y, Chang K, LeJeune W, Tilton RG, Monafo WW, Williamson JR. Diabetes impairs sciatic nerve hyperemia induced by surgical trauma: implications for diabetic neuropathy. THE AMERICAN JOURNAL OF PHYSIOLOGY 1997; 273:E174-84. [PMID: 9252494 DOI: 10.1152/ajpendo.1997.273.1.e174] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The most widely used methods to assess nerve blood flow in diabetics rats are hydrogen clearance polarography and laser Doppler flowmetry, techniques requiring surgical exposure of the nerve. In these experiments, we examined the hypothesis that the trauma of surgical exposure introduces an important and hitherto largely unrecognized variable that could account for discordant reports on nerve blood flow changes induced by diabetes. We used the noninvasive (for sciatic nerve) reference sample microsphere method to quantify sciatic nerve blood flow in unexposed va. surgically exposed nerves in rats with streptozotocin-induced diabetes (at different temperatures and after curarization) and in unexposed vs. surgically exposed nerves in galactose-fed rats. Baseline resting blood flow in unexposed nerves in both animal models of diabetes was either normal or increased (but was decreased in diabetic rats given d-tubocurarine). Furthermore, the normal brisk hyperemic nerve blood flow response to the minimal trauma associated with surgical exposure of the nerve was markedly impaired in diabetic and in galactose-fed rats. Normalization of the blood flow response to trauma in galactose-fed rats by an aldose reductase inhibitor suggests that the impairment is linked to increased polyol pathway metabolism. These findings 1) confirm our previous findings that sciatic nerve blood flow in diabetic rats is increased or unchanged in unexposed nerves, while also confirming reports that in surgically exposed nerves blood flow is higher in control than in diabetic rats, and 2) indicate that blood flows in surgically exposed nerves are largely a measure of vascular responses to injury rather than (patho)physiological blood flow in undisturbed nerves.
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Chang K, Ido Y, LeJeune W, Williamson JR, Tilton RG. Increased sciatic nerve blood flow in diabetic rats: assessment by "molecular" vs. particulate microspheres. THE AMERICAN JOURNAL OF PHYSIOLOGY 1997; 273:E164-73. [PMID: 9252493 DOI: 10.1152/ajpendo.1997.273.1.e164] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Sciatic nerve blood flow in diabetic rats in typically increased or unchanged when assessed by the reference sample microsphere method in our laboratory. In contrast, blood flow is generally reported to be decreased approximately 50% when assessed with laser Doppler flowmetry or hydrogen clearance polarography. To address concerns that increased blood flow observed with microspheres might be anomalous because of their particulate nature and/or because insufficient numbers of microspheres are captured in the nerve, a plasma-soluble "molecular microsphere" ([3H]desmethylimipramine, mol wt = 266) and 11.3-micron 153Gd-labeled microspheres were injected sequentially to assess blood flow in rats with streptozotocin diabetes of 2-4 wk duration. Nerve blood flows in diabetic rats were increased 1.5- to 2-fold (vs. control rats) with both tracers; these increases were prevented by tolrestat, an inhibitor of aldose reductase. These observations indicate that blood flow in sciatic nerve (like that in retina and kidney) is increased early after the onset of diabetes and is 1) demonstrable with a plasma-soluble tracer as well as with particulate microspheres and 2) linked to increased metabolism of glucose via the sorbitol pathway.
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183
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Yokomizo T, Izumi T, Chang K, Takuwa Y, Shimizu T. A G-protein-coupled receptor for leukotriene B4 that mediates chemotaxis. Nature 1997; 387:620-4. [PMID: 9177352 DOI: 10.1038/42506] [Citation(s) in RCA: 732] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Leukotriene B4 (LTB4) is a potent chemoattractant that is primarily involved in inflammation, immune responses and host defence against infection. LTB4 activates inflammatory cells by binding to its cell-surface receptor (BLTR). LTB4 can also bind and activate the intranudear transcription factor PPAR alpha, resulting in the activation of genes that terminate inflammatory processes. Here we report the cloning of the complementary DNA encoding a cell-surface LTB4 receptor that is highly expressed in human leukocytes. Using a subtraction strategy, we isolated two cDNA clones (HL-1 and HL-5) from retinoic acid-differentiated HL-60 cells. These two clones contain identical open reading frames encoding a protein of 352 amino acids and predicted to contain seven membrane-spanning domains, but different 5'-untranslated regions. Membrane fractions of Cos-7 cells transfected with an expression construct containing the open reading frame of HL-5 showed specific LTB4 binding, with a K(d) (0.154nM) comparable to that observed in retinoic acid-differentiated HL-60 cells. In CHO cells stably expressing this receptor, LTB4 induced increases in intracellular calcium, D-myo-inositol-1,4,5-triphosphate (InsP3) accumulation, and inhibition of adenylyl cyclase. Furthermore, CHO cells expressing exogenous BLTR showed marked chemotactic responses towards low concentrations of LTB4 in a pertussis-toxin-sensitive manner. Our findings, together with previous reports, show that LTB4 is a unique lipid mediator that interacts with both cell-surface and nuclear receptors.
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184
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Ham DI, Chang K, Chung H. Preretinal neovascularization induced by experimental retinal vein occlusion in albino rats. KOREAN JOURNAL OF OPHTHALMOLOGY 1997; 11:60-4. [PMID: 9283155 DOI: 10.3341/kjo.1997.11.1.60] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Retinal ischemia and neovascularization have been demonstrated in several animal models. To determine 1) whether the retinal or preretinal neovascularization can be induced in albino rats by retinal vein occlusion and 2) the type and rate of occurrence on neovascularization, we occluded retinal veins in albino rats by photodynamic thrombosis. After anesthesia, each of 36 rats received an injection of rose bengal photosensitive dye, and their veins underwent argon green laser treatment. Half or all the major retinal veins were occluded in 12 eyes and in 24 eyes, respectively. Ten control rats underwent the same procedures but the laser beam was directed between major retinal vessels. In 46 control eyes, rose bengal dye was seen to have perfused without laser treatment. Retinal detachment developed in most vein occluded eyes within one day of venous occlusion, which was confirmed by fluorescein angiography. On follow-up at two weeks, only four of 24 eyes (16.7%) had undergone occlusion of all retinal veins showed new preretinal vessels on the optic disc. In these four eyes, severe disturbance of both retinal arterial and venous blood flow was observed, but no other eyes showed such severe combined disturbance. These data suggest that preretinal neovascularization in albino rats can be induced by this minimally traumatic method and that venous occlusion is severe enough to compromise arterial blood flow for a certain threshold period, thus inducing the development of preretinal neovascularization.
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185
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Brinkmann U, Webber K, Di Carlo A, Beers R, Chowdhury P, Chang K, Chaudhary V, Gallo M, Pastan I. Cloning and expression of the recombinant FAb fragment of monoclonal antibody K1 that reacts with mesothelin present on mesotheliomas and ovarian cancers. Int J Cancer 1997; 71:638-44. [PMID: 9178820 DOI: 10.1002/(sici)1097-0215(19970516)71:4<638::aid-ijc21>3.0.co;2-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The monoclonal antibody (MAb) K1 recognizes an approximate 40 kDa glycoprotein, mesothelin, that is present on the surface of human mesothelial cells, mesotheliomas and ovarian cancers. We have cloned the cDNAs encoding the variable regions of MAb K1 and constructed plasmids for expression of recombinant K1(FAb). Recombinant FAb was produced in Escherichia coli in inclusion bodies that were solubilized and refolded to active protein. Binding of K1 MAb and FAb was compared by radioactive binding and competition assays and by surface plasmon resonance (BIAcore). Recombinant K1(FAb) binds to cells expressing K1-antigen with a similar affinity as papain derived FAb from K1(IgG) and with a 4- to 10-fold reduced affinity compared with bivalent IgG. The cloned FAb can be used to make higher affinity antibodies and immunoconjugates that could be useful for various types of immunotherapies.
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186
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Chie W, Lee W, Li C, Huang C, Chang K, Yen M, Lin R. Lactation, lactation suppression hormones and breast cancer. Oncol Rep 1997; 4:319-326. [PMID: 21590051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
One hundred and fifty-four parous women with pathologically confirmed newly diagnosed breast cancer in National Taiwan University Hospital were selected as the case group. Three hundred and eighty-six parous inpatient controls were individually matched for each case by age and date of admission. Information was collected from questionnaire interview and medical record. Effects of lactation and lactation suppression hormone were assessed with conditional logistic regression analysis. In univariate analysis, lactation had a weak protective effect, after adjusting for educational level, body mass index, family history of breast cancer, reproductive factors, oral contraceptive and lactation suppression hormone use, the weak negative associations changed to weak positive ones. The use of lactation suppression hormone was consistently associated with a higher breast cancer risk. The major confounders between lactation and breast cancer risk were parity and age at first full-term birth. Lower breast cancer risks were found in high parity - long lactation, and in younger ages at first full-term birth - long lactation groups. The differences among different lactation lengths within each parity and age at first full-term birth category were small. The protective effects disappeared after adjusting for other potential confounders. The results of this study questions the independent protective effect of lactation in a population having both a variable duration of lactation and rapid socioeconomic change. The role of lactation suppression hormones needs further study.
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187
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Chie W, Lee W, Li C, Huang C, Chang K, Yen M, Lin R. Lactation, lactation suppression hormones and breast cancer. Oncol Rep 1997. [DOI: 10.3892/or.4.2.319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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188
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Nyengaard JR, Chang K, Berhorst S, Reiser KM, Williamson JR, Tilton RG. Discordant effects of guanidines on renal structure and function and on regional vascular dysfunction and collagen changes in diabetic rats. Diabetes 1997; 46:94-106. [PMID: 8971088 DOI: 10.2337/diab.46.1.94] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We examined the effects of aminoguanidine and methylguanidine on vascular dysfunction, glomerular structural changes, and indexes of early and late nonenzymatic glycation in 7-month streptozotocin-induced diabetic rats. Kidney weight, glomerular volume, fractional mesangial volume, glomerular capillary basement membrane width, and urinary albumin excretion were increased in diabetic rats. Diabetes also 1) increased vascular albumin permeation twofold in retina, sciatic nerve, aorta, skin, and kidney; 2) decreased renal collagenase-soluble collagen; 3) increased collagen-associated fluorescence in kidney and skin but not in aorta; and 4) increased glycated hemoglobin levels and aortic pentosidine levels. Aminoguanidine reduced albuminuria by 70% after 4 months, and both guanidines 1) normalized aortic pentosidine levels and renal collagenase-soluble collagen, 2) had no effect on glycated hemoglobin levels or collagen-associated fluorescence (in aorta, kidney, or skin), and 3) had little or no effect on regional albumin permeation. These discordant effects of aminoguanidine on diabetes-induced vascular changes versus parameters of nonenzymatic glycation are consistent with a multifactorial pathogenesis of diabetic complications, including roles for metabolic imbalances independent of nonenzymatic glycation. To the extent that glomerular matrix accumulation and increased regional albumin permeation in chronically diabetic rats are sequelae of nonenzymatic glycation, these findings point to an important role for early glycation reactions and products.
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Abstract
Phage display has been used to select single-chain Fvs (scFvs) against mesothelin, a surface antigen present on mesothelial cells as well as mesotheliomas and non-mucinous ovarian cancers. Several attempts to produce anti-mesothelin hybridomas from spleen cells of mice immunized with recombinant mesothelin were unsuccessful. This report describes the isolation of anti-mesothelin scFvs from a phage display library made from the mRNA of the same spleens. Panning on recombinant antigen produced in E. coli or on antigen positive cells was employed. Several scFvs which bind specifically to mesothelin were isolated. Panning on recombinant antigen yielded five different scFvs. Panning on cells selected two different scFvs which also differ from the scFvs selected by recombinant antigen. The heavy chains of the scFvs selected on recombinant antigen are derived from four different heavy chain gene families and the scFvs selected on cells are derived from two of these families. In contrast, the light chains of all of these scFvs are derived from family XI. Moreover, the light chains of the two scFvs selected on cells are very similar to the light chains of two of the scFvs selected by panning on recombinant mesothelin except for a few point mutations. One of these scFvs which have been studied in detail has been shown to bind specifically to mesothelin positive transfected cells.
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190
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Tsai SJ, Lee YC, Chang K, Sim CB. [Psychiatric emergency consultation in a general hospital]. CHANGGENG YI XUE ZA ZHI 1996; 19:337-42. [PMID: 9041764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Inpatients in general hospital often presented with psychological problems and some of them need emergent psychiatric interventions. However, there have been little attention on the psychiatric emergency consultation. The purpose of this paper is to review the psychiatric emergency service in a general hospital over 3-year period. During this period, there were 88 psychiatric emergency consultations that represented 2.3% of all psychiatric consultations. The emergency group showed no difference in sex and age, but received more diagnoses of delirium (58.0%) than the other referrals. About one fourth of these patients had psychiatric history. Stated requests for "agitation and irritability", "psychiatric symptoms" and "uncooperation with treatment" were the most frequent reasons. Sixty-five percent of the patients receive recommendations of medication treatment. Among them, neuroleptics and anxiolytics were most common used. About one half of the patients needed further medical tests. After psychiatric interventions, most of the patients got improved within 2 days but 15 patients died during hospitalization. These findings indicated that psychiatric emergency consultation though the request rate is low. When making diagnoses in emergency consultation, past psychiatric history is important and organic mental disorders should be ruled out first. After psychiatric interventions, most of the psychiatric emergency could be improved. It suggested that the setting of psychiatric emergency consultation could improve the quality of patient care in a ageneral hospital.
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191
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Yang CH, Lee YC, Lin CH, Chang K. Conversion disorders in childhood and adolescence: a psychiatric consultation study in a general hospital. ZHONGHUA MINGUO XIAO ER KE YI XUE HUI ZA ZHI [JOURNAL]. ZHONGHUA MINGUO XIAO ER KE YI XUE HUI 1996; 37:405-9. [PMID: 9074275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
From March 1986 to April 1995, 418 consecutive psychiatric consultations for patients aged 18 or below were completed. Ten of these patients met the Diagnostic and Statistical Manual of Mental Disorders, 4th. edition (DSM-IV) diagnostic criteria for a conversion disorder. The medical and psychiatric consultation records of these patients were reviewed. Chief conversion symptoms included pseudoseizure (four cases), gait disturbance (two cases), abnormal movement (one case), four limbs weakness (one case), aphonia (one case) and tunnel vision (one case). The psychosocial problems of the patients included family problems (seven cases), interpersonal problems (two case) and concurrent physical illness (one case). Six patients (60%) manifested complete remission and others showed improvement of the symptoms.
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Cahn M, Chang K, Nguyen P, Butler J. Impact of endoscopic ultrasound with fine-needle aspiration on the surgical management of pancreatic cancer. Am J Surg 1996; 172:470-2. [PMID: 8942546 DOI: 10.1016/s0002-9610(96)00222-x] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Endoscopic ultrasound (EUS) with EUS-guided fine-needle aspiration (EUS-FNA) enables one to visualize the pancreas and surrounding structures and can provide access for FNA of those structures that appear suspicious for tumor. PATIENTS AND METHODS From 1993 to 1995, 50 patients suspected of having pancreatic cancer underwent EUS/EUS-FNA and abdominal computed tomography (CT). Malignancy was found in 30 (60%) cases, which included 24 (48%) pancreatic adenocarcinomas. RESULTS Endoscopic ultrasound/EUS-FNA identified 26 of the 30 malignancies (85%) and 21 of the 24 pancreatic adenocarcinomas (88%), with no false positives. Thirteen of the 24 pancreatic cancer patients had lymph nodes that were sampled with EUS/EUS-FNA. Seven of these 13 patients (62%) were found to have metastatic spread to lymph nodes. Operations were performed on 11 of the pancreatic cancer patients. Of these 11, the 5 that were predicted to be resectable by EUS/EUS-FNA underwent successful resection. Of the 6 predicted to be unresectable, 5 had palliative biliary bypasses, and 1 had a grossly positive margin of resection. CONCLUSIONS Endoscopic ultrasound/EUS-FNA can identify patients for curative surgical resection. It can also preoperatively identify patients with regional nodal disease for inclusion in appropriately designed clinical trials.
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193
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Khatib, O, Yokoi K, Chang K, Ruspini D, Holmberg R, Casal A. Coordination and decentralized cooperation of multiple mobile manipulators. ACTA ACUST UNITED AC 1996. [DOI: 10.1002/(sici)1097-4563(199611)13:11<755::aid-rob6>3.0.co;2-u] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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194
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Chang K, Rani AS, Chang K, Kumar S. Plasminogen activator activity is decreased in rat gingiva during diabetes. J Periodontol 1996; 67:743-47. [PMID: 8866312 DOI: 10.1902/jop.1996.67.8.743] [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: 02/02/2023]
Abstract
Diabetes produces extensive alterations of collagen metabolism including enhanced gingival collagenase activity. However, the mechanism for this enhanced enzyme activity is unclear. Collagenase is secreted from cells in a latent form and plasmin has been proposed as an important in vivo activator of procollagenase. Plasmin is converted from its precursor, plasminogen, by the proteolytic action of a serine proteinase, plasminogen activator (PA). The current study was therefore undertaken to determine the effect of diabetes on gingival PA activity in the rat. Since doxycycline is a potent collagenase inhibitor, the effect of doxycycline on gingival PA activity was also investigated. Eighteen male, Sprague-Dawley rats were made diabetic by streptozotocin injection (7 mg/100 g). Control rats (N = 8) were sham-treated. Doxycycline (5 mg/day/rat) was administered to 9 of the 18 diabetic rats by gavage on a daily basis. The other 9 diabetic rats were administered with saline. After 3 weeks, blood and gingival tissue were collected from each rat for the determination of glucose level and gingival PA activity. The tissues were then minced and extracted with 5 mM sodium phosphate containing 1% Triton X-100. PA assay was performed using chromatogenic substrate to determine PA activity in the extracts. Gingival PA activity in the diabetic rats was significantly reduced compared to the control (13.5 +/- 1.6 vs. 36.0 +/- 3.3 microunits/100 micrograms protein, P < 0.01). Doxycycline administration to diabetic rats had no effect on the already reduced gingival PA activity (10.4 +/- 3.5 in doxycycline-treated rats vs. 13.5 +/- 1.6 mu units/100 micrograms protein in untreated diabetic rats). PA activities in gingival tissues from the diabetic, nondiabetic control and doxycycline-treated diabetic groups were also demonstrated on zymographs as lytic bands. Regarding the well-known fact that gingival collagenase activity is enhanced during diabetes, our results did not support the notion that this biochemical alteration is attributed to increased activation of procollagenase by PA.
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195
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Worrall NK, Chang K, Suau GM, Allison WS, Misko TP, Sullivan PM, Tilton RG, Williamson JR, Ferguson TB. Inhibition of inducible nitric oxide synthase prevents myocardial and systemic vascular barrier dysfunction during early cardiac allograft rejection. Circ Res 1996; 78:769-79. [PMID: 8620596 DOI: 10.1161/01.res.78.5.769] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
NO is produced during cardiac allograft rejection by expression of inducible NO synthase (iNOS) in the rejecting heart. Recent evidence indicates that NO modulates vascular permeability under both physiological and pathophysiological conditions. The present study explored the effects of early acute cardiac allograft rejection, and specifically the effects of NO, on myocardial and systemic vascular barrier function using a quantitative double-tracer permeation method in a rat cardiac transplant model. Early allograft rejection increased albumin permeation twofold to fivefold in the allograft heart and systemic vasculature (brain, lung, sciatic nerve, diaphragm, retina, muscle, kidney, and uvea) compared with isografts and controls. There were no detectable differences in regional blood flow or hemodynamics, suggesting that increased albumin permeation resulted from increased vascular permeability. iNOS mRNA was expressed in the allograft heart and native lung and was associated with increased serum nitrite/nitrate levels. iNOS inhibition with aminoguanidine prevented or attenuated allograft heart and systemic vascular barrier dysfunction and reduced allograft serum nitrite/nitrate levels to isograft values. Aminoguanidine did not affect the mild histological changes of rejection present in allografts. These data demonstrate the novel observations that (1) endothelial barrier function is compromised in the systemic vasculature, particularly in the brain, remote from the site of allograft rejection; (2) allograft vascular barrier dysfunction is associated with increased NO production and iNOS mRNA expression in the affected tissues (eg, native lung and grafted heart); and (3) inhibition of NO production by iNOS prevents vascular barrier dysfunction in the allograft heart and systemic vasculature.
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196
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Chang K, Pastan I. Molecular cloning of mesothelin, a differentiation antigen present on mesothelium, mesotheliomas, and ovarian cancers. Proc Natl Acad Sci U S A 1996; 93:136-40. [PMID: 8552591 PMCID: PMC40193 DOI: 10.1073/pnas.93.1.136] [Citation(s) in RCA: 526] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Monoclonal antibody MAb K1 recognizes a 40-kDa glycoprotein present on the surface of mesothelial cells, mesotheliomas, and ovarian cancers. We have used MAb K1 to isolate a 2138-bp cDNA that encodes this antigen. The cDNA has an 1884-bp open reading frame encoding a 69-kDa protein. When the cDNA was transfected into COS and NIH 3T3 cells, the antigen was found on the cell surface and could be released by treatment with phosphatidylinositol-specific phospholipase C. The 69-kDa precursor is processed to the 40-kDa form. The protein has been named mesothelin because it is made by mesothelial cells. Mesothelin may play a role in cellular adhesion.
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197
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Hirsch MS, Chang K, Kao WW, Svoboda KK. Intracellular distribution of type II collagen mRNA and prolyl 4-hydroxylase in embryonic avian corneal epithelia. Anat Rec (Hoboken) 1996; 244:1-14. [PMID: 8838419 DOI: 10.1002/(sici)1097-0185(199601)244:1<1::aid-ar1>3.0.co;2-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND The distribution of endoplasmic reticulum (ER) proteins and type II collagen mRNA in whole mount preparations of embryonic corneal epithelia was investigated. We asked, do transmission electron microscopy (TEM) and confocal microscopy of chick prolyl 4-hydroxylase (CPH) show similar ER distributions as CPH is necessary for collagen biosynthesis? METHODS The overall distribution of ER was analyzed by TEM. Collagen secreting ER was localized with antibodies to chick prolyl 4-hydroxylase (CPH, CPH-alpha, or CPH-beta subunits). Type II collagen mRNA distribution was determined by in situ hybridization. RESULTS The ER localized with TEM, and immunohistochemistry using anti-CPH antibodies, showed similar distribution patterns. Immunostaining for CPH and CPH-beta was prominent in both periderm and basal cells and also appeared to stain the periderm apical surface. CPH-alpha was less intense, only localizing to ER regions. The basal cell CPH distribution appeared perinuclear in optical sections that contained nuclei, but occupied nearly all the cytoplasm in a reticular pattern above and below nuclei, similar to that seen with TEM cross-sections. Epithelia double labeled with propidium iodide and CPH showed overlapping cytoplasmic staining. The distribution of type II collagen mRNA was similar to the ER staining pattern, appearing to represent a subset of total ER. CONCLUSIONS This study demonstrates that ER markers have a similar distribution as type II collagen mRNA in embryonic avian corneal epithelia. In addition the CPH subunits had distinct, but overlapping distributions, suggesting that they may act independently.
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198
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Ichikawa Y, Mitsuhashi M, Ishikawa T, Wyle F, Chang K, Fujiwara Y, Arakawa T, Shimada H, Tarnawski A. Laboratory diagnosis of Helicobacter pylori infection by polymerase chain reaction. RESEARCH COMMUNICATIONS IN MOLECULAR PATHOLOGY AND PHARMACOLOGY 1996; 91:117-28. [PMID: 8824937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Although the detection of Helicobacter pylori (Hp) infection is important, it is a rather difficult task using only conventional diagnostic techniques. In this study, we have applied a polymerase chain reaction (PCR)-based assay for the diagnosis of Hp infection. RT-PCR for Hp ribosomal RNA was utilized, using the gastric biopsy specimens obtained endoscopically from 10 patients. PCR primers have been designed from the highly consensus region of the 7 different Hp rRNA sequences in GenBank. In the detection of Hp, PCR was more sensitive than culturing and showed 100% of the sensitivity and specificity compared with histology. Our primer pair could detect as few as 50 organisms per reaction. RT-PCR for Hp rRNA is a sensitive and specific method to detect Hp infection in the gastric mucosa.
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199
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Chang K, Hanaoka K, Kumada M, Takuwa Y. Molecular cloning and functional analysis of a novel P2 nucleotide receptor. J Biol Chem 1995; 270:26152-8. [PMID: 7592819 DOI: 10.1074/jbc.270.44.26152] [Citation(s) in RCA: 207] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The cDNA encoding a novel P2 receptor was isolated from rat aortic smooth muscle cell library and functionally characterized. The cloned P2 receptor exhibits structural features characteristic of the G protein-coupled receptor family and shows 44 and 38% amino acid identity with previously cloned rat P2U and chicken P2Y receptors, respectively. The cloned P2 receptor is functionally coupled to phospholipase C but not to adenylate cyclase in C6 rat glioma cells transfected with the cloned P2 expression vector. The rank order of agonist potency as judged by intracellular Ca2+ mobilization responses is UTP > ADP = 2-methylthioATP > ADP beta S > ATP = ATP gamma S, which is not compatible with any of the previously characterized P2 receptor subtypes. The nonselective P2 antagonists, suramin and reactive blue-2, inhibit nucleotide-induced phospholipase C activation in cells expressing the cloned P2 receptor. The cloned P2 receptor mRNA is abundantly expressed in various rat tissues including lung, stomach, intestine, spleen, mesentery, heart, and, most prominently, aorta. The results indicate that the novel metabotropic P2 receptor has pharmacological characteristics distinct from any of P2 receptor subtypes thus far identified and suggest the existence of a novel regulatory system by extracellular nucleotides of potential significance.
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MESH Headings
- Adenine Nucleotides/pharmacology
- Adenosine Diphosphate/pharmacology
- Adenylate Cyclase Toxin
- Amino Acid Sequence
- Animals
- Aorta/metabolism
- Base Sequence
- Blotting, Northern
- Calcium/metabolism
- Cells, Cultured
- Chickens
- Cloning, Molecular/methods
- Colforsin/pharmacology
- Cyclic AMP/metabolism
- DNA, Complementary
- Gene Library
- Glioma
- Inositol Phosphates/metabolism
- Kidney/metabolism
- Male
- Molecular Sequence Data
- Muscle, Smooth, Vascular/metabolism
- Oligodeoxyribonucleotides
- Organ Specificity
- Pertussis Toxin
- Purinergic P2 Receptor Agonists
- Rats
- Receptors, Purinergic P2/biosynthesis
- Receptors, Purinergic P2/chemistry
- Recombinant Proteins/biosynthesis
- Recombinant Proteins/chemistry
- Recombinant Proteins/metabolism
- Sequence Homology, Amino Acid
- Transfection
- Tumor Cells, Cultured
- Virulence Factors, Bordetella/pharmacology
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200
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Tsai SJ, Lee YC, Chang K, Sim CB. Psychiatric consultations in pediatric inpatients. ZHONGHUA MINGUO XIAO ER KE YI XUE HUI ZA ZHI [JOURNAL]. ZHONGHUA MINGUO XIAO ER KE YI XUE HUI 1995; 36:411-4. [PMID: 8592926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Emotional problems are not uncommon in hospitalized children. The authors reviewed psychiatric consultations on a pediatric ward in a medical center and compared the findings with a non-pediatric group and the Western reports. Forty consultations were requested in a three-year period which represented 0.35% of all admissions to pediatric ward and 1.0% of all psychiatric consultations in that period. The consultation rate of the pediatric ward is significantly lower than that of the non-pediatric wards. The most common reason for the referrals was for the evaluation of possible psychopathogeneses from unexplained physical symptoms. A wide range of psychiatric diagnoses were found. Among them, adjustment disorders, anxiety or somatoform disorders, diagnosis deferred and no psychiatric diagnosis were the most commonly made. Pediatric patients had a similar percentage diagnosis of adjustment disorders compared with the non-pediatric group but far less organic mental disorders. Besides medication, psychological and family intervention were frequently recommended by the psychiatrists. These findings suggest that there were unique psychological characteristics in the hospitalized children which required specialists and further studies. It is hoped that increasing the collaboration between pediatricians and psychiatrists can improve the medical care of these sick children.
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