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Chang E, Chang WJ, Wang BC, Yang CY. Plasma spraying of zirconia-reinforced hydroxyapatite composite coatings on titanium: part I: phase, microstructure and bonding strength. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 1997; 8:193-200. [PMID: 15348759 DOI: 10.1023/a:1018583522322] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Plasma-sprayed hydroxyapatite (HA) coatings applied to metal substrates can induce a direct chemical bond with bone and hence achieve biological fixation of the implant. However, the poor bonding strength between HA and substrate has been of concern to orthopaedists. In this study, two submicrometre ZrO2 powders stabilized with both 3 and 8 mol% Y2O3 (TZ3Y and TZ8Y, respectively) were incorporated in a plasma-sprayed HA coating on Ti-6Al-4V substrate to investigate the change in phase, microstructure and bonding strength. The results show that ZrO2 composite coatings contain more unmelted particles and greater porosity. During plasma spraying, ZrO2 reacts with the CaO in HA to form CaZrO3 and accelerates HA decomposition to alpha-TCP and Ca4P2O9. Nevertheless, bonding strength increases with increase of ZrO2 content in the range 0 to 10 wt% studied. The higher Y2O3-containing TZ8Y apparently exerts a greater strengthening effect than the lower Y2O3-containing TZ3Y.
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Wang CH, Wang HM, Chen JS, Chang WJ, Lai GM. Intensive chemotherapy plus recombinant human granulocyte-colony stimulating factor support for distant metastatic nasopharyngeal carcinoma. A preliminary report. Oncology 1997; 54:34-7. [PMID: 8978590 DOI: 10.1159/000227658] [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: 02/03/2023]
Abstract
Nasopharyngeal carcinoma (NPC) has been shown to be highly responsive to chemotherapy. The major limiting toxicity was myelotoxicity. Recently, the role of granulocyte colony-stimulating factor (G-CSF) in reducing chemotherapy-induced neutropenic sepsis has been well established. In this study, we tested whether recombinant human G-CSF (rhG-CSF) could effectively support the bone marrow function in both previously untreated and pretreated metastatic NPC patients receiving intensive chemotherapy. Twelve patients with distant metastatic disease, 5 newly diagnosed (group A) and 7 pretreated patients (group B), were enrolled to receive BEC (bleomycin, epirubicin and cisplatin), followed by rhG-CSF support (50 microg/m2 s.c. daily for 10 days) every 4 weeks for two cycles. Four patients in group A completed the treatment as scheduled while only 2 patients in group B did. After the first treatment cycle, 6 patients (50%) had grade III-IV myelosuppression. Five of the patients were from group B. The mean values of the white cell count nadir were 2,680 (range 1,200-3,700) in group A and 1,343 (range 400-2,900) in group B (p = 0.0386). Neutropenia-associated fever occurred in 7 patients, 6 of whom had received previous treatment. There were 2 deaths due to toxicity, and both patients had liver metastases within 6 months following radiation. After 24 months of follow-up, only 1 patient is still alive. Our preliminary results suggest that in previously treated metastatic NPC patients, bone marrow suppression is still the major limiting toxic side effect of aggressive chemotherapy, especially for those patients with liver recurrences within 6 months after irradiation and despite rhG-CSF support.
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Chang WJ, Nowinski TS, Repke CS, Buerger DG. Spontaneous orbital hemorrhage in pregnant women treated with subcutaneous heparin. Am J Ophthalmol 1996; 122:907-8. [PMID: 8956657 DOI: 10.1016/s0002-9394(14)70399-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE To describe two pregnant women who developed spontaneous orbital hemorrhage following treatment with subcutaneous heparin. METHOD Case histories and subsequent management of spontaneous orbital hemorrhage. RESULTS Both women developed severe unilateral visual loss. CONCLUSION In spontaneous orbital hemorrhage, anticoagulation therapy such as heparin may contribute to severe hemorrhage and visual loss.
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Chang WJ, Iannaccone ST, Lau KS, Masters BS, McCabe TJ, McMillan K, Padre RC, Spencer MJ, Tidball JG, Stull JT. Neuronal nitric oxide synthase and dystrophin-deficient muscular dystrophy. Proc Natl Acad Sci U S A 1996; 93:9142-7. [PMID: 8799168 PMCID: PMC38609 DOI: 10.1073/pnas.93.17.9142] [Citation(s) in RCA: 283] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Neuronal nitric oxide synthase (nNOS) in fast-twitch skeletal muscle fibers is primarily particulate in contrast to its greater solubility in brain. Immunohistochemistry shows nNOS localized to the sarcolemma, with enrichment at force transmitting sites, the myotendinous junctions, and costameres. Because this distribution is similar to dystrophin, we determined if nNOS expression was affected by the loss of dystrophin. Significant nNOS immunoreactivity and enzyme activity was absent in skeletal muscle tissues from patients with Duchenne muscular dystrophy. Similarly, in dystrophin-deficient skeletal muscles from mdx mice both soluble and particulate nNOS was greatly reduced compared with C57 control mice. nNOS mRNA was also reduced in mdx muscle in contrast to mRNA levels for a dystrophin binding protein, alpha 1-syntrophin. nNOS levels increased dramatically from 2 to 52 weeks of age in C57 skeletal muscle, which may indicate a physiological role for NO in aging-related processes. Biochemical purification readily dissociates nNOS from the dystrophin-glycoprotein complex. Thus, nNOS is not an integral component of the dystrophin-glycoprotein complex and is not simply another dystrophin-associated protein since the expression of both nNOS mRNA and protein is affected by dystrophin expression.
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Chang WJ, Shields CL, Shields JA, DePotter PV, Schiffman R, Eagle RC, Nelson LB. Bilateral orbital involvement with massive allergic fungal sinusitis. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 1996; 114:767-8. [PMID: 8639099 DOI: 10.1001/archopht.1996.01100130759031] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Chang WJ, Goyal AK, Flanagan JC. Dacryoadenitis presenting with eyelid retraction. OPHTHALMIC SURGERY 1995; 26:380-2. [PMID: 8532298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Chang WJ, Barb CR, Kraeling RR, Rampacek GB, Wright JT. Biogenic amines in the hypothalamus of rats after diethyldithiocarbamate or AIMAX treatment, an alternative for norepinephrine depletion. J Anim Sci 1995; 73:1147-51. [PMID: 7628959 DOI: 10.2527/1995.7341147x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The objective of this study was to determine whether AIMAX (a dithiocarbamoylhydrazine derivative) is suitable for determining the effects of norepinephrine (NE) depletion on reproduction in domestic animals. Therefore, the effect of AIMAX (n = 6) on concentrations of biogenic amines in the medial basal hypothalamus (MBH) and anterior hypothalamic area (AHA) of ovariectomized (OVX) rats primed with ovarian steroids was compared to that of diethyldithiocarbamate (DDC; n = 5), a potent dopamine-beta-hydroxylase (DBH) inhibitor, which is chemically similar to AIMAX. Rats that received only ovarian steroids and saline injections served as controls (n = 6). Treatment with DDC resulted in sedation and reduced body temperature. In contrast, rats behaved normally after AIMAX treatment. AI-MAX reduced (P < .05) NE but increased (P < .05) dopamine (DA) concentrations in MBH and AHA compared with controls. Similar changes in NE and DA concentrations were observed in DDC-treated rats. However, elevated epinephrine (EPI) levels were measured in MBH and AHA of only DDC-treated rats. Serum LH concentrations were suppressed (P < .005) in both AIMAX- and DDC-treated rats compared with control animals. Because AIMAX, like DDC, suppressed hypothalamic NE content and LH secretion, AIMAX should be useful in studying effects of NE depletion on gonadotropin secretion in domestic animals.
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Chang WJ, Nowinski TS, Eagle RC. A large oncocytoma of the caruncle. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 1995; 113:382. [PMID: 7887854 DOI: 10.1001/archopht.1995.01100030138038] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Chang WJ, Rapuano CJ. Management of an anterior chamber eyelash. OPHTHALMIC SURGERY 1994; 25:741-2. [PMID: 7898875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Barb CR, Chang WJ, Leshin LS, Rampacek GB, Kraeling RR. Opioid modulation of gonadotropin releasing hormone release from the hypothalamic preoptic area in the pig. Domest Anim Endocrinol 1994; 11:375-82. [PMID: 7828431 DOI: 10.1016/0739-7240(94)90009-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Two experiments (Exp) were conducted to examine in vitro the release of gonadotropin releasing hormone (GnRH) from the hypothalamus after treatment with naloxone (NAL) or morphine (MOR). In Exp 1, hypothalamic-preoptic area (HYP-POA) collected from 3 market weight gilts at sacrifice and sagittally halved were perifused for 90 min prior to a 10 min pulse of morphine (MOR; 4.5 x 10(-6) M) followed by NAL (3.1 x 10(-5) M) during the last 5 min of MOR (MOR + NAL; n = 3). The other half of the explants (n = 3) were exposed to NAL for 5 min. Fragments were exposed to KCl (60 mM) at 175 min to assess residual GnRH releasability. In Exp 2, nine gilts were ovariectomized and received either oil vehicle im (V; n = 3); 10 micrograms estradiol-17 beta/kg BW in 42 hr before sacrifice (E; n = 3); .85 mg progesterone/kg BW in twice daily for 6 d prior to sacrifice (P4; n = 3). Blood was collected to assess pituitary sensitivity to GnRH (.2 microgram/kg BW) on the day prior to sacrifice. On the day of sacrifice HYP-POA explants were collected and treated as described in Exp 1 except tissue received only NAL. In Exp 1, NAL increased (P < .05) GnRH release. This response to NAL was attenuated (P < .05) by coadministration of MOR. Cumulative GnRH release after NAL was greater (P < .05) than after MOR + NAL. All tissues responded similarly to KCl with an increase (P < .05) in GnRH release.(ABSTRACT TRUNCATED AT 250 WORDS)
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Chang WJ, Ying YS, Rothberg KG, Hooper NM, Turner AJ, Gambliel HA, De Gunzburg J, Mumby SM, Gilman AG, Anderson RG. Purification and characterization of smooth muscle cell caveolae. J Biophys Biochem Cytol 1994; 126:127-38. [PMID: 8027172 PMCID: PMC2120085 DOI: 10.1083/jcb.126.1.127] [Citation(s) in RCA: 295] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Plasmalemmal caveolae are a membrane specialization that mediates transcytosis across endothelial cells and the uptake of small molecules and ions by both epithelial and connective tissue cells. Recent findings suggest that caveolae may, in addition, be involved in signal transduction. To better understand the molecular composition of this membrane specialization, we have developed a biochemical method for purifying caveolae from chicken smooth muscle cells. Biochemical and morphological markers indicate that we can obtain approximately 1.5 mg of protein in the caveolae fraction from approximately 100 g of chicken gizzard. Gel electrophoresis shows that there are more than 30 proteins enriched in caveolae relative to the plasma membrane. Among these proteins are: caveolin, a structural molecule of the caveolae coat; multiple, glycosylphosphatidylinositol-anchored membrane proteins; both G alpha and G beta subunits of heterotrimeric GTP-binding protein; and the Ras-related GTP-binding protein, Rap1A/B. The method we have developed will facilitate future studies on the structure and function of caveolae.
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Chang WJ, Barb CR, Kraeling RR, Rampacek GB, Asanovich KM. N-methyl-d,l-aspartate modulation of pituitary hormone secretion in the pig: role of opioid peptides. Domest Anim Endocrinol 1993; 10:305-13. [PMID: 8306634 DOI: 10.1016/0739-7240(93)90034-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Sixteen ovariectomized (OVX) mature gilts, averaging 139.6 +/- 3.1 kg body weight (BW) were assigned randomly to receive either progesterone (P, 0.85 mg/kg BW, n = 8), or corn oil vehicle (OIL, n = 8) injections im twice daily for 10 d. On the day of experiment, all gilts received either the EAA agonist, N-methyl-d,l-aspartate (NMA; 10 mg/kg BW, iv) alone or NMA plus the EOP antagonist, naloxone (NAL, 1 mg/kg BW, iv), resulting in the following groups of 4 gilts each: OIL-NMA, OIL-NMA-NAL, P-NMA and P-NMA-NAL. Blood samples were collected via jugular cannula every 15 min for 6 hr. All pigs received NMA 5 min following pretreatment with either 0.9% saline or NAL 2 hr after blood collection began and a GnRH challenge 3 hr after NMA. Administration of NMA suppressed (P < 0.03) LH secretion in OIL-NMA gilts and treatment with NAL failed to reverse the suppressive effect of NMA on LH secretion in OIL-NMA-NAL gilts. Similar to OIL-NMA gilts, NMA decreased (P < 0.03) mean serum LH concentrations in P-NMA gilts. However, in P-NMA-NAL gilts, serum LH concentrations were not changed following treatment. All gilts responded to GnRH with increased (P < 0.01) LH secretion. Additionally, administration of NMA increased (P < 0.01) growth hormone (GH) and prolactin (PRL) secretion in both OIL-NMA and P-NMA gilts, but this increase in GH and PRL secretion was attenuated (P < 0.01) by pretreatment with NAL in OIL-NMA-NAL and P-NMA-NAL gilts.(ABSTRACT TRUNCATED AT 250 WORDS)
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Chang WJ, Barb CR, Kraeling RR, Rampacek GB, Leshin LS. Involvement of the central noradrenergic system in opioid modulation of luteinizing hormone and prolactin secretion in the pig. Biol Reprod 1993; 49:176-80. [PMID: 8353185 DOI: 10.1095/biolreprod49.1.176] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The role of norepinephrine (NE) in the progesterone (P)-dependent endogenous opioid peptide (EOP) suppression of LH and prolactin (PRL) secretion in the pig was studied. Fifteen ovariectomized gilts treated with P (0.85 mg/kg b.w. i.m.) twice daily for 10 days were assigned, 5 gilts each, to the following treatment groups: 1) control, 2) AIMAX (N-methyl-N1[1-methyl-2-propenyl]1,2 hydrazinedicarbothioamide), and 3) anti-GnRH serum. On day 4 of P treatment, AIMAX (125 mg per 1.8 kg feed/day), previously shown to be an NE synthesis inhibitor, was fed daily for 7 days to group 2. On the last day of P treatment, group 3 gilts received an i.v. injection of anti-GnRH serum at 0800 h while Group 1 animals received an i.v. injection of serum collected from hypophysectomized gilts. Jugular blood samples were collected every 15 min for 9 h starting at 1000 h. All gilts received two injections of naloxone (NAL; 1 mg/kg b.w., i.v.) at 1400 h and 1600 h and an injection of a GnRH analogue (D-[Ala6-desGly-NH10]-ethylamide; 5 micrograms/pig, i.v.) at 1800 h. Pretreatment serum LH concentrations were lower (p < 0.05) in AIMAX-treated gilts (0.19 +/- 0.09 ng/ml) than in controls (0.53 +/- 0.09 ng/ml), but were similar to those in GnRH antiserum-treated gilts (0.32 +/- 0.09 ng/ml). NAL increased (p < 0.001) serum LH concentrations in control animals and averaged 1.6 +/- 0.2 ng/ml the first h. AIMAX and anti-GnRH serum blocked the NAL-induced LH secretion. Serum PRL concentrations averaged 6.0 +/- 0.1 ng/ml for all groups.(ABSTRACT TRUNCATED AT 250 WORDS)
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Chang WJ, Goetz MB. Toxoplasma gondii peritonitis. HAWAII MEDICAL JOURNAL 1993; 52:174-175. [PMID: 8340224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Toxoplasma gondii most often causes encephalitis in HIV-infected patients; infections of other organs are much less often clinically apparent. In particular, peritonitis caused by T. gondii in an Human Immunodeficiency Virus (HIV)-infected patient has been reported only once previously. Herein we report a second case.
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Barb CR, Cox NM, Carlton CA, Chang WJ, Randle RF. Growth hormone secretion, serum, and cerebral spinal fluid insulin and insulin-like growth factor-I concentrations in pigs with streptozotocin-induced diabetes mellitus. PROCEEDINGS OF THE SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE. SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE (NEW YORK, N.Y.) 1992; 201:223-8. [PMID: 1409737 DOI: 10.3181/00379727-201-43503] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Diabetes mellitus was induced using streptozotocin in five gilts between 8 and 12 weeks of age. Gilts were maintained with exogenous insulin (INS) except during experimental periods. Four litter-mate gilts served as controls. At 9 months of age, all gilts were ovariectomized, and 30 days after ovariectomy, Experiment (Exp) 1 was conducted. Jugular vein catheters were inserted and blood samples were collected every 10 min for 8 hr. Experiment 2 was conducted when gilts were 11 months of age. Venous blood and cerebrospinal fluid (CSF) samples were collected in the absence (Phase I) or presence (Phase II) of INS therapy. In Experiment 1, plasma glucose concentrations were greater (P < 0.05) in diabetic (465 +/- 17 mg/100 ml) than in control (82 mg +/- 17 mg/100 ml) gilts, whereas serum INS was lower (P < 0.0001) in diabetic gilts (0.3 +/- 0.02 vs 0.9 +/- 0.05 ng/ml) and insulin-like growth factor-I was similar in diabetic and control gilts (32 +/- 3 vs 43 +/- 4 ng/ml, respectively). Mean serum GH concentration was 2-fold greater (P < 0.02) in diabetics (2.8 +/- 0.4 ng/ml) than in control gilts (1.2 +/- 0.2 ng/ml). Diabetic gilts exhibited a greater (P < 0.05) number of GH pulses than control gilts (3.2 +/- 0.4 vs 1.5 +/- 0.3/8 hr, respectively). In addition, GH pulse magnitude was markedly elevated (P < 0.02) in diabetic (5.8 +/- 0.4 ng/ml) compared with control gilts (3.3 +/- 0.6 ng/ml). Mean basal serum GH concentrations were greater (P < 0.07) in diabetic (2.2 +/- 0.5 ng/ml) compared with control gilts (1.0 +/- .1 ng/ml). In Experiment 2, CSF concentrations of insulin-like growth factor-I, INS, GH, and protein were similar for diabetic and control gilts in both phases. Serum GH levels were similar for diabetics and controls in Phase I, but were greater (P < 0.05) in diabetics than in controls in Phase II. CSF glucose levels were greater in diabetic than in control gilts in both the presence (P < 0.003) and absence (P < 0.0002) of INS therapy, whereas plasma glucose was greater (P < 0.003) in diabetic than in control gilts in the absence of INS, but returned to control concentrations in the presence of INS. However, serum GH levels were unchanged after INS therapy in the diabetic gilts. In conclusion, altered GH secretion in the diabetic gilt may, in part, be due to elevated CSF glucose concentrations, which may alter GH-releasing hormone and/or somatostatin secretion from the hypothalamus.
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Chang WJ, Rothberg KG, Kamen BA, Anderson RG. Lowering the cholesterol content of MA104 cells inhibits receptor-mediated transport of folate. J Biophys Biochem Cytol 1992; 118:63-9. [PMID: 1618907 PMCID: PMC2289528 DOI: 10.1083/jcb.118.1.63] [Citation(s) in RCA: 187] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The folate receptor is clustered on the surface of MA104 cells in association with caveolae. This relationship is thought to be essential for the proper internalization and recycling of the receptor during the delivery of 5-methyltetrahydrofolate to the cytoplasm of folate-depleted cells. Both the clustered organization of the receptor and the integrity of caveolae are disrupted when cells are deprived of cholesterol. We now show that cholesterol depletion of MA104 cells markedly reduces the rate of 5-methyltetrahydrofolate internalization and causes a 70% decline in the number of receptors present in the internal, recycling compartment. This effect is consistent with morphologic data showing that cholesterol-depleted MA104 cells have a reduced number of caveolae as well as fewer receptors per caveolae.
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Barb CR, Derochers GM, Johnson B, Utley RV, Chang WJ, Rampacek GB, Kraeling RR. N-methyl-d,l-aspartate stimulates growth hormone and prolactin but inhibits luteinizing hormone secretion in the pig. Domest Anim Endocrinol 1992; 9:225-32. [PMID: 1458876 DOI: 10.1016/0739-7240(92)90036-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The effects of n-methyl-d,l-aspartate (NMA), a neuroexcitatory amino acid agonist, on luteinizing hormone (LH), prolactin (PRL) and growth hormone (GH) secretion in gilts treated with ovarian steroids was studied. Mature gilts which had displayed one or more estrous cycles of 18 to 22 d were ovariectomized and assigned to one of three treatments administered i.m.: corn oil vehicle (V; n = 6); 10 micrograms estradiol-17 b/kg BW given 33 hr before NMA (E; n = 6); .85 mg progesterone/kg BW given twice daily for 6 d prior to NMA (P4; n = 6). Blood was collected via jugular cannulae every 15 min for 6 hr. Pigs received 10 mg NMA/kg BW i.v. 2 hr after blood collection began and a combined synthetic [Ala15]-h GH releasing factor (1-29)-NH2 (GRF; 1 micrograms/kg BW) and gonadotropin releasing hormone (GnRH; .2 micrograms/kg BW) challenge given i.v. 3 hr after NMA. NMA did not alter LH secretion in E gilts. However, NMA decreased (P < .02) serum LH concentrations in V and P4 gilts. Serum LH concentrations increased (P < .01) after GnRH in all gilts. NMA did not alter PRL secretion in P4 pigs, but increased (P < .01) serum PRL concentrations in V and E animals. Treatment with NMA increased (P < .01) GH secretion in all animals while the GRF challenge increased (P < .01) serum GH concentrations in all animals except in V treated pigs. NMA increased (P < .05) cortisol secretion in all treatment groups. These results indicate that NMA inhibits LH secretion and is a secretagogue of PRL, GH and cortisol secretion with ovarian steroids modulating the LH and PRL response to NMA.
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Chang WJ, Goetz MB. Response to treatment of infection due to Mycobacterium avium complex with trimethoprim-sulfamethoxazole. Clin Infect Dis 1992; 14:1267-8. [PMID: 1623090 DOI: 10.1093/clinids/14.6.1267] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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Lee YC, Chang WJ, Yang PC. [Effect of combinations of anticancer drugs with interferons on human lung cancer cell lines evaluated by human tumor clonogenic assay]. J Formos Med Assoc 1991; 90:880-5. [PMID: 1720164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Using the double agar layer method of human tumor clonogenic assay, the anticancer effect of different combinations of anticancer drugs and interferons was tested on 3 lung cancer cell lines, PC-13, PC-14, and Calu-1. The anticancer drugs and the concentrations used in this study were cisplatin (1.0 microgram/mL), adriamycin (1.0 microgram/mL), mitomycin C (0.2 microgram/mL), VP-16 (5.0 micrograms/mL) and 5-FU (5.0 micrograms/mL). Three kinds of interferon, alpha, beta and gamma in 5,000 units/mL, were tested in combination or in sequence with other anticancer drugs on lung cancer cell lines. The results demonstrate an enhanced anticancer effect on PC-14 only with sequential or simultaneous combination of VP-16 with alpha, beta and gamma interferons; and on Calu-1, only with sequential use of adriamycin and beta-interferon. Our results indicate that there is no unique way of combining anticancer drugs and interferons which can obtain an enhanced anticancer effect on all lung cancer cell lines. The best combination of interferon and anticancer drugs seems to be influenced by the biological characteristics of the cancer cells.
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Yang PQ, Liu SY, Cao ZH, Chang WJ, Che CT. Cucurbitacin contents in Hemsleya dolichocarpa. THE AMERICAN JOURNAL OF CHINESE MEDICINE 1991; 19:51-6. [PMID: 1897490 DOI: 10.1142/s0192415x91000077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Hemsleya dolichocarpa was studied for its cucurbitacin contents during growing period. A colorimetric method was used to determine the total cucurbitacin levels, and a TLC densitometric assay was employed for estimating dihydrocucurbitacin F and its acetate, two active principles in Hemsleya plants. Cucurbitacin contents rise progressively from May to November; the month of November is thus the most desirable time for harvesting plant materials for medicinal uses. It was noticed that the spoiled plant samples gave an intense color reaction while dihydrocucurbitacin F and its acetate levels were not significantly altered. The accuracy of the assays is discussed.
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Matteo RS, Schwartz AE, Ornstein E, Young WL, Chang WJ. Pharmacokinetics of sufentanil in the elderly surgical patient. Can J Anaesth 1990; 37:852-6. [PMID: 2147593 DOI: 10.1007/bf03006620] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The effect of age on the distribution and elimination of sufentanil was studied in seven elderly (77 +/- 5 yr, mean +/- SD) and seven younger (41 +/- 15 yr) neurosurgical patients. Following a single IV bolus of sufentanil 2 micrograms.kg-1 multiple arterial samples were obtained at timed intervals and plasma concentrations of sufentanil were measured by radioimmunoassay. Pharmacokinetic variables were calculated from the derived compartmental models. The initial volume of distribution was significantly smaller in the elderly patients (310 +/- 109 ml.kg-1 vs 491 +/- 112 ml.kg-1 mean +/- SD). Elimination half-lives, plasma clearances, and total volumes of distribution were similar for elderly and younger subjects. Six of seven elderly patients required administration of naloxone at the termination of surgery to achieve an adequate rate of ventilation (greater than eight breaths.min-1) while only one younger patient required antagonism of ventilatory depression. The authors believe that age-related differences in the action of sufentanil cannot be accounted for by the observed differences in the initial volume of distribution. It is concluded that alterations in pharmacodynamics appear to be of greater importance in the prolonged opioid effect seen in the elderly.
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Leshin LS, Rund LA, Thompson FN, Mahaffey MB, Chang WJ, Byerley DJ, Kiser TE. Serum prolactin and growth hormone responses to naloxone and intracerebral ventricle morphine administration in heifers. J Anim Sci 1990; 68:1656-65. [PMID: 2384365 DOI: 10.2527/1990.6861656x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
These studies examined responses of serum prolactin (PRL) and growth hormone (GH) to opioid agonist and antagonist administration in heifers. To minimize nonspecific and behavioral effects and to facilitate future studies with specific opioid receptor agonists, a cannula was placed within the third cerebral ventricle of the brain of 4- to 10-mo-old heifers to directly access hypothalamic regions involved in the regulation of PRL and GH secretion. Increasing doses of morphine (M) from 2 to 1,500 micrograms injected into the third cerebral ventricle increased (P less than .001) serum PRL concentrations in a dose-related manner. Growth hormone responses were variable, resulting in elevated (P less than .05) serum concentrations following morphine, but no dose-related effects were apparent. Both PRL and GH responses to 700 micrograms M were absent when an intracerebral ventricle injection of an equimolar dose of naloxone, an opioid receptor antagonist, was administered prior to M. In a replicated 4 x 4 latin square, the effects of intravenous naloxone on PRL and GH responses was tested in young (86 +/- 11 d) and older (234 +/- 6 d) heifers. Naloxone at doses of 1, 2 and 4 mg/kg reduced (P less than .05) serum concentrations of PRL for 45 to 60 min. Mean concentrations of GH tended to be higher (P less than .07) in older heifers All doses of naloxone decreased (P less than .05) serum GH concentrations in older heifers but proved ineffective in younger heifers. There were no differences between doses of naloxone on either PRL or GH. These data suggest that endogenous opioids are involved in the regulation of PRL and GH secretion in heifers.
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73
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Lee TC, Wei ML, Chang WJ, Ho IC, Lo JF, Jan KY, Huang H. Elevation of glutathione levels and glutathione S-transferase activity in arsenic-resistant Chinese hamster ovary cells. IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY : JOURNAL OF THE TISSUE CULTURE ASSOCIATION 1989; 25:442-8. [PMID: 2732199 DOI: 10.1007/bf02624629] [Citation(s) in RCA: 86] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Arsenic-resistant Chinese hamster ovary (CHO) cells were established by progressively increasing the concentration of sodium arsenite in culture medium. One of the resistant clones, SA7, was also cross-resistant to As(V), Zn, Fe(II), Co, and Hg. The susceptibilities to sodium arsenite in parental CHO cells, revertant SA7N cells, and resistant SA7 cells were correlated with their intracellular glutathione (GSH) levels and glutathione S-transferase (GST) activity. The resistance in SA7 cells was diminished by depletion of GSH in cells after treatment with buthionine sulfoximine. Furthermore, after reexposure of revertant SA7N cells to sodium arsenite, the intracellular GSH levels, GST activity, and resistance to sodium arsenite were raised to the same levels as SA7 cells. These data indicate that the elevation of intracellular GSH levels and GST activity in SA7 cells may be responsible for the resistance to arsenite. A p25 protein, which could be a monomer subunit of GST, accumulated in SA7 cells. In addition, an outward transport inhibitor, verapamil, indiscriminately increased the arsenite toxicity in resistant and parental cells.
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Hsiao KJ, Lee FY, Wu SJ, Chang WJ. Determination of erythrocyte porphobilinogen deaminase activity using porphobilinogen as substrate. Clin Chim Acta 1987; 168:257-8. [PMID: 3677422 DOI: 10.1016/0009-8981(87)90296-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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75
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Lee TC, Tzeng SF, Chang WJ, Lin YC, Jan KY. Post-treatments with sodium arsenite during G2 enhance the frequency of chromosomal aberrations induced by S-dependent clastogens. Mutat Res 1986; 163:263-9. [PMID: 3785262 DOI: 10.1016/0027-5107(86)90024-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Treatment with sodium arsenite during the G2 phase potentiated the chromatid breaks and chromatid exchanges induced by ultraviolet light or 4-nitroquinoline 1-oxide but not those induced by methyl methanesulfonate, ethyl methanesulfonate, mitomycin C or cisplatin in Chinese hamster ovary cells. A comparison was made between the effects of treatment during G2 with sodium arsenite, cytosine-beta-D-arabinofuranoside, aphidicolin, hydroxyurea, caffeine, 3-aminobenzamide and novobiocin on the frequency of chromosomal aberrations induced by the above-mentioned S-dependent clastogens. It was found that the effects varied considerably, both quantitatively and qualitatively. However, potentiation was more often observed in the chromosomal aberrations induced by ultraviolet light and 4-nitroquinoline 1-oxide than by other S-dependent clastogens, and the frequency of chromatid exchanges was potentiated only in cells pretreated with ultraviolet light or 4-nitroquinoline 1-oxide. Furthermore, for all of the S-dependent clastogens studied, treatment with cytosine-beta-D-arabinofuranoside during the G2 phase potentiated the frequency of chromatid breaks but not the frequency of chromatid exchanges.
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Abstract
Numerous pathogenic bacteria are found in seawater. They can cause several environmental infections, such as conjunctivitis, otitis externa, wound infections, pneumonia, and gastrointestinal illness. The incidence of some of these infections could be lowered if people took care to avoid eating undercooked seafood, swimming in brackish water, or sustaining lacerations in a marine environment. However, such infections will probably increase in frequency as more people visit ocean resorts. Prompt elimination of the infective agent, adequate wound care, and avoidance of reexposure can minimize the severity of the condition.
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Chang WJ, Horiuchi S, Takahashi K, Yamasaki M, Yamada Y. The structure and function of acid proteases. VI. Effects of acid protease-specific inhibitors on the acid proteases from Aspergillus niger var. macrosporus. J Biochem 1976; 80:975-81. [PMID: 12156 DOI: 10.1093/oxfordjournals.jbchem.a131385] [Citation(s) in RCA: 44] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
1. The Type B acid protease from Aspergillus niger var. macrosporus was inactivated by reaction with diazoacetyl-DL-norleucine methyl ester (DAN), DL-1-diazo-3-tosylamido-2-heptanone (DTH), and L-1-diazo-3-tosylamido-4-phenyl-2-butanone (DTPB) in the presence of cupric ions. The reaction with DAN took place with 1:1 stoichiometry. The enzyme was also inactivated by reaction with 1, 2-epoxy-3-(p-nitrophenoxy)-propane (EPNP) with concomitant incorporation of approximately two EPNP molecules per molecule of protein. Moreover, these reactions of DAN and of EPNP were markedly inhibited by pepstatin. These results seem to indicate that, as in the case of porcine pepsin [EC 3.4.23.1] and related acid proteases, the enzyme has two essential carboxyl groups at the active site, one reactive with DAN and related diazo reagents in the presence of cupric ions and the other reactive with EPNP, and that pepstatin binds in the vicinity of these residues. 2. The Type A acid protease from the same mold, on the other hand, was found to be markedly less sensitive to these specific inhibitors. Under conditions where the Type B enzyme was completely inactivated by DAN and related diazo reagents, only partial inactivation of this enzyme occurred. The effect of prior mixing of DAN and cupric ions on the pH profile of inactivation was also different from that for the Type B enzyme. Moreover, the Type A enzyme was not inactivated by EPNP. These results thus indicate that the nature of the active site of the Type A enzyme is rather different from that of the Type B enzyme and hence that the Type A enzyme belongs to a different class of acid proteases from the Type B enzyme.
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78
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Takahashi K, Chang WJ. The structure and function of acid proteases. V. Comparative studies on the specific inhibition of acid proteases by diazoacetyl-DL-norleucine methyl ester, 1,2-epoxy-3-(p-nitrophenoxy) propane and pepstatin. J Biochem 1976; 80:497-506. [PMID: 10290 DOI: 10.1093/oxfordjournals.jbchem.a131304] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Comparative studies have been made on the effects of diazoacetyl-DL-norleucine methyl ester (DAN), 1,2-epoxy-3-(p-nitrophenoxy)propane (EPNP) and pepstatin on acid proteases, including those from Acrocylindrium sp., Aspergillus niger, Aspergillus saitoi, Mucor pusillus, Paecilomyces varioti, Rhizopus chinensis, and Trametes sanguinea, and also porcine pepsin [EC 3.4.23.1] and calf rennin [EC 3.4.23.4] for comparative purposes. These enzymes were rapidly inactivated at similar rates and in 1:1 stiochiometry by reaction with DAN in the presence of cupric ions. The pH profiles of inactivation of these enzymes were similar and had optima at pH 5.5 to 6. They were also inactivated at similar rates by reaction with EPNP, with concomitant incorporation of nearly 2 EPNP molecules per molecule of enzyme. The pH profiles of inactivation were again similar and maximal inactivation was observed at around pH 3 to 4. Some of the EPNP-inactivated enzymes were treated with DAN and shown still to retain reactivity toward DAN. All these enzymes were inhibited strongly by pepstatin, and the reactions of DAN and EPNP with them were also markedly inhibited by prior treatment with pepstatin. These results indicate that the active sites of these enzymes are quite similar and that they presumably have at least two essential carboxyl groups at the active site in common, one reactive with DAN in the presence of cupric ions and the other reactive with EPNP, as has already been demonstrated for porcine pepsin and calf rennin. Pepstatin appears to bind at least part of the active site of each enzyme in a simmilar manner.
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Takahashi K, Chang WJ, Arima K. The structure and function of acid proteases. IV. Inactivation of the acid protease from Mucor pusillus by acid protease-specific inhibitors. J Biochem 1976; 80:61-7. [PMID: 9381 DOI: 10.1093/oxfordjournals.jbchem.a131258] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Mucor pusillus acid protease was rapidly inactivated with 1 : 1 stoichiometry by reaction with diazoacetyl-DL-norleucine methyl ester (DAN) in the presence of cupric ions. Cupric ions were essential for this inactivation. The rate of inactivation was maximal at around pH 6 when the enzyme was mixed with DAN and cupric ions without prior mixing of the reagents, and at pH 5.3 when DAN and cupric ions were mixed and incubated before addition to the enzyme solution. In both cases, the rate of inactivation decreased as the pH was either increased or decreased. The amino acid composition of an acid hydrolysate of the DAN-Modified enzyme was indistinguishable from that of the native enzyme except for the incorporation of about one norleucine residue per molecule of protein. The enzyme was also inactivated by reaction with 1,2-epoxy-3-(p-nitrophenoxy)-propane (EPNP). At the stage of about 90% inactivation, 1.50 residues of EPNP were incorporated per molecule of protein and the rate of inactivation followed pseudo-first order kinetics. The optimal pH for the inactivation was pH 3.0 and the rate of inactivation decreased as the pH was either increased or decreased. Furthermore, the enzyme was strongly inhibited by pepstatin, and the reactions of DAN and of EPNP was also inhibited significantly by prior treatment of the enzyme with pepstatin. These results suggest that the enzyme may have two essential carboxyl groups at the active site, one reactive with DAN in the presence of cupric ions and the other with EPNP, and that pepstatin binds part of the active site to inhibit the reactions with DAN and EPNP as well as the enzyme activity.
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Chang WJ, Takahashi K. The structure and function of acid proteases. III. Isolation and characterization of the active-site peptides from bovine rennin. J Biochem 1974; 76:467-74. [PMID: 4612029 DOI: 10.1093/oxfordjournals.jbchem.a130590] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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81
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Chang WJ, Takahashi K. The structure and function of acid proteases. I. Inactivation of bovine rennin by acid protease-specific inhibitors. J Biochem 1973; 74:231-7. [PMID: 4586672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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82
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Takahashi K, Chang WJ. Specific chemical modifications of acid proteases in the presence and absence of pepstatin. J Biochem 1973; 73:675-7. [PMID: 4579426 DOI: 10.1093/oxfordjournals.jbchem.a130129] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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83
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Eisler DM, Hill B, Von Metz EK, Chang WJ, Heckly RJ. Anti-Pasteurella pestis factor from mice and guinea pigs. II. Some chemical and physical characteristics. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1967; 98:576-83. [PMID: 6020580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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