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Liu JZ, Yang HY, Weng LP, Ji LN. Synthesis of glucose oxidase and catalase by Aspergillus niger in resting cell culture system. Lett Appl Microbiol 1999; 29:337-41. [PMID: 10701992 DOI: 10.1046/j.1472-765x.1999.00637.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The synthesis of glucose oxidase and catalase by Aspergillus niger was investigated using a resting cell culture system without growth being established. Calcium carbonate induced the synthesis of both enzymes and calcium chloride inhibited it. The optimal pH for the biosynthesis of glucose oxidase and catalase was 6.0 and 5.7, respectively. The effects of other bivalent cations, reductive compounds and metabolic products on enzyme synthesis were also tested. The biosynthesis of glucose oxidase and catalase was promoted by MnCO3, thioglycolic acid, pyroracemic acid and gluconic acid.
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Ogawa Y, Okamoto S, Wakui M, Watanabe R, Yamada M, Yoshino M, Ono M, Yang HY, Mashima Y, Oguchi Y, Ikeda Y, Tsubota K. Dry eye after haematopoietic stem cell transplantation. Br J Ophthalmol 1999; 83:1125-30. [PMID: 10502571 PMCID: PMC1722843 DOI: 10.1136/bjo.83.10.1125] [Citation(s) in RCA: 171] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIMS To determine the incidence, natural course, and severity of dry eye occurring or worsening after haematopoietic stem cell transplantation (SCT). METHODS At a tertiary care hospital, 53 patients undergoing allogeneic or autologous SCT followed by at least 180 days of follow up were studied prospectively. Examination included grading of symptoms of dry eye, evaluation of ocular surface, tear break up time, and Schirmer tests with and without nasal stimulation. Meibomian gland secretion was also examined using a slit lamp while applying steady digital pressure. RESULTS Of the 53 patients, 44 received allografts. Half of these patients (22) developed dry eye or their pre-existing dry eye worsened after SCT, while none of nine autograft recipients did. Onset of dry eye was 171 (SD 59) days after SCT. Two types of dry eye occurred. One (n=10) was severe with ocular surface findings resembling Sjögren's syndrome and reduction of reflex tearing soon after onset. A mild type (n=12) had unimpaired reflex tearing. Meibomian gland dysfunction (MGD) was more frequent and severe in patients with dry eye and chronic graft versus host disease (GVHD), and overall severity of dry eye was greater in patients with MGD and chronic GVHD. CONCLUSIONS Dry eye after SCT occurred only in allograft recipients, and was not evident in autograft recipients. The severe form of dry eye had a tendency to develop rapidly. Further study on the prediction and treatment of severe dry eye after SCT is necessary.
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Fan LM, Wu WH, Yang HY. Identification and characterization of the inward K+ channel in the plasma membrane of Brassica pollen protoplasts. PLANT & CELL PHYSIOLOGY 1999; 40:859-865. [PMID: 10555306 DOI: 10.1093/oxfordjournals.pcp.a029615] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Patch clamp techniques have been used to identify and characterize the whole-cell currents carried by inward K+ channels in isolated matured pollen protoplasts of Brassica chinensis var. chinensis. The whole-cell inward currents in the isolated pollen protoplasts were activated at hyperpolarized membrane potentials more negative than -100 mV. The magnitudes of the whole-cell inward currents were strongly dependent on the external K+ concentration, and were highly selective for K+ over other monovalent cations. The inward currents were not observed when external K+ was replaced with the same concentration of Cs+ or Na+. The addition of 1 mM or 10 mM Ba2+ in external solutions resulted in 30% or 80% inhibition of the inward currents at -180 mV, respectively. These results demonstrated that the inward K+ currents mainly account for the recorded whole-cell inward currents in Brassica pollen protoplasts. Increase of cytoplasmic Ca2+ concentrations from 10 nM to 30 microM or even 5 mM did not affect the inward K+ currents. Decrease of external Ca2+ concentrations from 10 mM to 1 mM inhibited the inward K+ currents by 25%, while the increase of external Ca2+ from 10 mM to 50 mM almost completely blocked the inward K+ currents. Physiological importance of K+ transport into pollen and its possible regulatory mechanisms are also discussed.
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Yang HY, Karoum F, Felder C, Badger H, Wang TC, Markey SP. GC/MS analysis of anandamide and quantification of N-arachidonoylphosphatidylethanolamides in various brain regions, spinal cord, testis, and spleen of the rat. J Neurochem 1999; 72:1959-68. [PMID: 10217273 DOI: 10.1046/j.1471-4159.1999.0721959.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Anandamide [N-arachidonoylethanolamide (NAE)] was initially isolated from porcine brain and proposed as an endogenous ligand for cannabinoid receptors in 1992. Accumulating evidence has now suggested that, in the tissue, NAE is generated from N-arachidonoylphosphatidylethanolamides (N-ArPEs) by phosphodiesterase. In this study a sensitive and specific procedure was developed to quantify NAE and N-ArPE, including organic solvent extraction, reverse-phase C-18 cartridge separation, derivatization, and gas chromatography/mass spectrometry (GC/MS) analysis. NAE is converted by a two-step derivatization procedure to a pentafluorobenzoyl ester followed by pentafluoropropionyl acylation. Quantification was performed by isotope dilution GC/MS using deuterium-labeled NAE (NAE-2H8) as an internal standard. The same chemical derivatization was applicable to N-ArPE quantification. The separated N-ArPE fractions were converted by a two-step cleavage/derivatization procedure into the pentafluorobenzoyl ester of NAE and then to its pentafluoropropionyl amide. The derivative was quantified by GC/MS using deuterium-labeled 1,2-[2H8]dioleoyl-sn-glycero-3-phospho(arachidonoyl)ethanolamid e as an internal standard. Using these methods, we have found that endogenous NAE levels in rat brain, spleen, testis, liver, lung, and heart were below the level of quantification achievable (0.1 pmol/mg of protein) but that N-ArPE is readily quantifiable and is widely distributed in the rat CNS with the highest level in the spinal cord. The striatum, hippocampus, and accumbens contain intermediate concentrations of N-ArPE, whereas the value is lowest in the cerebellum.
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Zhang WG, Li XW, Ma LP, Wang SW, Yang HY, Zhang ZY. Wild-type p53 protein potentiates phototoxicity of 2-BA-2-DMHA in HT29 cells expressing endogenous mutant p53. Cancer Lett 1999; 138:189-95. [PMID: 10378792 DOI: 10.1016/s0304-3835(99)00013-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
To better understand the effects of p53 on the process of photodynamic therapy (PDT)-induced cell death, we introduced a wild-type p53 gene into the HT29 colorectal carcinoma cell line, which bears an endogenous mutant p53, using a lipofectin system. The influence of p53 status on the sensitivity induced by 2-butylamino-2-demethoxy-hypocrellin A (2-BA-2-DMHA) photosensitization was then examined. The results indicate that infection with wild-type p53 induces a growth arrest but does not induce cell death, and sensitizes the cells to PDT. At a concentration of 5 microM 2-BA-2-DMHA with a red light of 18 J/cm2 (lambda = 600-700 nm), the survival is reduced from 58.72% in HT29 cells to 13.49% in wild-type p53-infected HT29 cells. Apoptosis following PDT appears earlier in HT29 cells infected with wild-type p53 than in parent HT29 cells and empty vector-infected HT29 cells. These findings suggest that although wild-type p53 is, by itself, insufficient to induce apoptosis in cells with p53 mutation, it enhances the photosensitivity of 2-BA-2-DMHA by strongly potentiating the induction of apoptosis.
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Lin HH, Yang TP, Jiang ST, Yang HY, Tang MJ. Bcl-2 overexpression prevents apoptosis-induced Madin-Darby canine kidney simple epithelial cyst formation. Kidney Int 1999; 55:168-78. [PMID: 9893125 DOI: 10.1046/j.1523-1755.1999.00249.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Madin-Darby canine kidney (MDCK) cells develop into simple epithelial cell cysts when cultured in type I collagen gel. We found that MDCK cells initially grow into multilayer cell aggregates and subsequently develop central lumen that contain apoptotic cells. We hypothesized that apoptosis might be essential for the formation of MDCK cysts. METHODS Using MDCK cells cultured in collagen gel as the experimental model, we investigated how renal cells organize to form cysts. To delineate the role of apoptosis in the process of cyst formation, MDCK cells were transfected with the bcl-2 gene. Characterization of apoptosis was studied by morphological and biochemical methods. RESULTS Bcl-2 overexpression conferred resistance to apoptosis. Cultured in collagen gel, Bcl-2 transfectants rarely formed a simple epithelial cyst, but instead remained as a multilayer cell aggregate containing central or multiple lumens, or even developing into branching structures. CONCLUSIONS Because Bcl-2 overexpression averts cyst cavitation, these data clearly indicate that apoptosis is an essential initial event for renal cyst formation.
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Jhamandas JH, Harris KH, Petrov T, Yang HY, Jhamandas KH. Activation of neuropeptide FF neurons in the brainstem nucleus tractus solitarius following cardiovascular challenge and opiate withdrawal. J Comp Neurol 1998; 402:210-21. [PMID: 9845244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Neuropeptide FF (NPFF), a morphine modulatory peptide, is localized within discrete autonomic regions including the brainstem nucleus tractus solitarius (NTS) and the parabrachial nucleus (PBN). We investigated the activation of NPFF neurons in the NTS of rats induced by cardiovascular challenge and centrally generated opiate withdrawal. For hypotensive stimulation, we used systemic infusions of sodium nitroprusside (NP) or hemorrhage (HEM), and hypertension was achieved by intravenous phenylephrine (PHENYL) or angiotensin II (AII). In rats that received continuous intracerebroventricular injections of morphine, intraperitoneal injections of naloxone precipitated behavioural signs of opioid withdrawal. Activated NTS neurons were identified by using a combined immunohistochemistry for Fos and NPFF, and neurons projecting to the PBN were determined with a retrograde tracer. HEM, administration of vasoactive drugs, and opiate withdrawal produced a very robust activation of NTS neurons. In NP and HEM groups, 25.6+/-3.2% and 7.6+/-1.3% of NPFF neurons were activated, respectively. Lesser numbers of NPFF neurons were activated in the PHENYL (4.6+/-1.6%) and AII (2.4+/-0.8%) groups. However, following opiate withdrawal, virtually no Fos expression was observed in NPFF neurons. NPFF neurons activated during NP infusion constituted the largest number of cells projecting to the PBN. This study shows that NPFF neurons in NTS that project to the PBN respond selectively to NP as opposed to other cardiovascular challenges or opiate withdrawal. These data support an emerging and important role for NPFF in the context of central cardiovascular regulation.
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Abstract
We report a case of leukemia cutis with atypical skin manifestations, presented with generalized various sized dark brownish to erythematous patches with plaques on the whole body of a 42-year-old man. Skin lesions developed 6 months ago and had no signs of itching or tenderness. He complained of sustaining fevers with abdominal discomfort. Laboratory findings showed elevation of leukocyte count and peripheral blood smear revealed 86% of lymphocyte. Histologic examination showed diffuse infiltration of abnormal cells that appeared to be leukemic in nature.
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Yu HJ, Lee SK, Son SJ, Kim YS, Yang HY, Kim JH. Steroid acne vs. Pityrosporum folliculitis: the incidence of Pityrosporum ovale and the effect of antifungal drugs in steroid acne. Int J Dermatol 1998; 37:772-7. [PMID: 9802688 DOI: 10.1046/j.1365-4362.1998.00229.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Steroid acne is a folliculitis that can result from systemic or topical administration of steroid, and has been described as showing a similar clinical picture to Pityrosporum folliculitis, but there have been few reports about the incidence of Pityrosporum ovale and the effect of antimycotic drugs in steroid acne and other acneiform eruptions. Our purpose was to describe the association between steroid acne and P. ovale, and to confirm the superior efficacy of oral antifungal drugs over anti-acne drugs in the treatment of steroid acne. METHODS The history, clinical features direct microscopy, histopathologic analysis, and therapeutic results of 125 cases with steroid acne or other acneiform eruptions were described and compared. RESULTS Over 80% of patients with acneiform eruption receiving systemic steroid revealed significant numbers of P. ovale in the lesional follicle. Furthermore, oral antifungal drug (itraconazole) showed significantly better clinical and mycologic effects than any other group of medications used in this study. CONCLUSIONS Steroid acne and other acneiform eruptions showing discrete follicular papules and/or pustules localized to the upper trunk and acneiform facial skin lesions associated with multiple acneiform lesions on the body in the summer period should be suspected as Pityrosporum folliculitis. In addition, oral antifungal drugs recommended for Pityrosporum folliculitis; however, it will require a larger case-control study to confirm the superiority of antifungal therapy over anti-acne treatment.
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Yang HY, Chen CF. Pharmacology and toxicology of herbal medicine: subacute toxicity of commonly used Chinese drugs. J Toxicol Sci 1998; 23 Suppl 2:229-33. [PMID: 9760471 DOI: 10.2131/jts.23.supplementii_229] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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261
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Ono M, Yagi Y, Goto E, Yang HY, Tsubota K. Evaluation of Schirmer tests by two types of tear clearance tests. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1998; 438:869-73. [PMID: 9634980 DOI: 10.1007/978-1-4615-5359-5_122] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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262
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Zhang WG, Weng M, Pang SZ, Zhang MH, Yang HY, Zhao HX, Zhang ZY. A novel photosensitizer, 2-butylamino-2-demethoxy-hypocrellin A (2-BA-2-DMHA). 1. Synthesis of 2-BA-2-DMHA and its phototoxicity to MGC803 cells. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1998; 44:21-8. [PMID: 9745725 DOI: 10.1016/s1011-1344(98)00101-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reaction of hypocrellin A (HA) with n-butylamine in pyridine under reflux leads to the formation of 2-butylamino-2-demethoxy-hypocrellin A (2-BA-2-DMHA), which is illustrated by ultraviolet-visible absorption spectra, proton nuclear magnetic resonance spectra, infrared spectra and mass spectra. The product exhibits stronger red-light absorption and has a much higher photopotentiation factor than HA (i.e., more than 200 versus four at a dose of 4 J cm-2 of red light on human gastric adenocarcinoma MGC803 cells). The mechanism of phototoxicity of 2-BA-2-DMHA on MGC803 cells irradiated with red light (lamada = 600-700 nm) has also been studied. An examination of extracted cellular DNA by agarose gel electrophoresis shows that the DNA has degraded into fragments with lengths which are multiples of approximately 180-190 base pairs (i.e., oligonucleosome size), a biochemical marker of apoptosis. Transmission electron microscopy reveals chromatin condensation around the periphery of the nucleus, which is also characteristic of apoptosis. This study suggests that 2-BA-2-DMHA is a potential photosensitizer and that its photoxicity to MGC803 cells proceeds via apoptosis.
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Yang HY, Wishart J, Yang YY, Lumeng J, Paik YK. A quantitative study of environmental asbestos exposure in Honolulu. HAWAII MEDICAL JOURNAL 1998; 57:536-9. [PMID: 9676039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The increased use of asbestos in various industries in past decades has led to increases in environmental asbestos pollution. Incidental exposure to asbestos is inevitable, and has generated public concern. We performed the following study aimed at determining the level of environmental asbestos exposure in Honolulu, and our results indicate that the levels of environmental asbestos in Honolulu are the lowest in the nation.
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Shimazaki J, Yang HY, Shimmura S, Tsubota K. Terrien's marginal degeneration associated with erythema elevatum diutinum. Cornea 1998; 17:342-4. [PMID: 9603393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE To describe a patient with Terrien's marginal degeneration associated with a chronic skin disease, erythema elevatum diutinum. METHODS A 27-year-old woman with peripheral thinning of her left cornea associated with adjacent conjunctival and episcleral inflammation was clinically examined. RESULTS Episodes of worsening skin lesions were associated with development of inflammation in her left eye. Administration of sulfones was effective for reducing both skin and ocular inflammation. CONCLUSION Erythema elevatum diutinum should be considered an underlying systemic disease of Terrien's marginal degeneration.
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Croxtall JD, Wu HL, Yang HY, Smith B, Sutton C, Chang BI, Shi GY, Flower R. Lipocortin 1 co-associates with cytokeratins 8 and 18 in A549 cells via the N-terminal domain. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1401:39-51. [PMID: 9459484 DOI: 10.1016/s0167-4889(97)00120-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
An affinity chromatography strategy was used to search for proteins in A549 cells which interact with the N-terminus of lipocortin 1 (annexin 1). Using the biologically active fragment Lc13-25 as the affinity ligand, two proteins of molecular weight (m.w.) 52 and 48kDa were extracted. Affinity blots of these proteins bound iodinated Lc13-25. Partial tryptic digests of these proteins were analysed by matrix assisted laser desorption mass spectrometry and found to display fragmentation patterns with a strong similarity to those of cytokeratin 8 and 18 respectively. Subsequent blotting with a panel of specific cytokeratin antibodies strongly supported the idea that the two proteins were cytokeratin 8 and cytokeratin 18. Cytokeratin 8 was isolated from A549 cells in intermediate filament (IF) preparations which were also found to contain lipocortin 1 as a potential intermediate filament associated protein (IFAP). This association persisted throughout cycles of IF assembly and disassembly. Dual-labelling immuno-histochemistry in A549 cells showed strong co-localization of lipocortin 1 and cytokeratin 8. The implications of this finding are discussed in the light of the biological activity and possible function of lipocortin 1.
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Yokoi H, Arima H, Kondo K, Murase T, Iwasaki Y, Yang HY, Oiso Y. Antiserum against neuropeptide FF augments vasopressin release in conscious rats. Peptides 1998; 19:393-5. [PMID: 9493874 DOI: 10.1016/s0196-9781(97)00375-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We previously reported that centrally administered neuropeptide FF (NPFF) inhibited arginine vasopressin (AVP) release. In this study, immunoneutralization of central NPFF was performed to evaluate the role of endogenous NPFF in the regulation of AVP release. Intracerebroventricular (ICV) injection of antiserum against NPFF (Anti-NPFF) significantly augmented the plasma AVP increase induced by hyperosmolality [intraperitoneal injection of hypertonic saline (600 mOsm/kg, 2% BW)] at 60 min after ICV injection compared with normal rabbit serum (NRS) (NRS: 4.20+/-0.30 pg/ml, Anti-NPFF: 5.83+/-0.46 pg/ml, p < 0.01). Anti-NPFF did not cause significant change in plasma osmolality, plasma volume or arterial blood pressure. This evidence indicates that endogenous NPFF might be physiologically involved in osmoregulation of the plasma AVP level through its inhibitory action.
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Yang HY, Fujishima H, Toda I, Itoh S, Bissen-Miyajima H, Shimazaki J, Tsubota K. Allergic conjunctivitis as a risk factor for regression and haze after photorefractive keratectomy. Am J Ophthalmol 1998; 125:54-8. [PMID: 9437313 DOI: 10.1016/s0002-9394(99)80234-7] [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: 02/05/2023]
Abstract
PURPOSE To analyze the relation between allergic conjunctivitis and the results of photorefractive keratectomy performed with an excimer laser in myopic eyes. METHODS Fifty-seven myopic eyes in 57 Japanese patients were classified into three groups: a normal group (30 eyes of 30 patients), a treatment group composed of eyes with allergic conjunctivitis that were treated with fluorometholone and cromolyn sodium eyedrops from month 3 until the end of the 12- to 18-month follow-up period (16 eyes of 16 patients), and a no-treatment group composed of eyes with allergic conjunctivitis that received no allergic treatment until the end of the follow-up period (11 eyes of 11 patients). Preoperative and postoperative examinations included evaluation of corrected and uncorrected visual acuity and grading of corneal haze. RESULTS In the no-treatment group, the mean corneal haze score +/- SD of 0.8 +/- 0.98 was significantly greater than the normal group score of 0.38 +/- 0.49 (P = .02). There was no significant difference in the haze score between the treated and normal groups. A refractive outcome of +/- 1 diopter was obtained in 30 (100%) of the 30 patients in the normal group, 15 (93.8%) of 16 patients in the treatment group, and four (36.4%) of the 11 patients in the no-treatment group. Visual acuity was 20/40 or better after photorefractive keratectomy in 30 patients (100%) in the normal group, 15 patients (93.8%) in the treatment group, and six patients (54.5%) in the no-treatment group. CONCLUSION These findings suggest that untreated allergic conjunctivitis is a significant risk factor for haze and myopic regression after photorefractive keratectomy.
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Goodman CB, Heyliger S, Emilien B, Partilla JS, Yang HY, Lee CH, Cadet JL, Rothman RB. Regulation of mu binding sites after chronic administration of antibodies directed against specific anti-opiate peptides. Peptides 1998; 19:1703-9. [PMID: 9880075 DOI: 10.1016/s0196-9781(98)00121-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
There is some indication that anti-opiate peptides (AOP) modulate opioid receptor systems by altering mu-receptor density. To further characterize this phenomenon, we investigated the effects of continuous infusion of anti-AOP IgG on mu binding sites in the brains of rats. Specifically, male Sprague-Dawley rats received intracerebroventricular (i.c.v.) infusions for 13 days of either control (rabbit) IgG or test IgGs: anti-dynorphin A IgG, anti-dynorphin A1-8 IgG, anti-alpha-MSH IgG, or the monoclonal anti-NPFF IgG. Administration of anti-NPFF IgG or the anti-dynorphin1-8 IgG significantly increased mu labeling by 40-70% in several brain regions at the caudate level. Contrary to these findings, anti-alpha-MSH IgG decreased (19-32%) [125I]-DAMGO labeling in several thalamic nuclei. The results suggest that the density of mu-opioid receptors is regulated in part by anti-opiate peptides in the extracellular fluid of the brain.
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MESH Headings
- Animals
- Antibodies, Anti-Idiotypic/administration & dosage
- Antibodies, Anti-Idiotypic/immunology
- Antibodies, Anti-Idiotypic/pharmacology
- Binding Sites
- Brain Chemistry
- Dynorphins/immunology
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-
- Enkephalins
- Epitopes/drug effects
- Epitopes/immunology
- Epitopes/radiation effects
- Immunoglobulin G/administration & dosage
- Immunoglobulin G/immunology
- Immunoglobulin G/pharmacology
- Injections, Intraventricular
- Iodine Radioisotopes
- Male
- Opioid Peptides/immunology
- Opioid Peptides/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/metabolism
- Receptors, Opioid, mu/physiology
- alpha-MSH/immunology
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Shimazaki J, Yang HY, Tsubota K. Amniotic membrane transplantation for ocular surface reconstruction in patients with chemical and thermal burns. Ophthalmology 1997; 104:2068-76. [PMID: 9400767 DOI: 10.1016/s0161-6420(97)30057-8] [Citation(s) in RCA: 277] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
OBJECTIVE The purpose of the study is to examine the usefulness of preserved human amniotic membrane transplantation in patients with chemical and thermal burns. DESIGN The study design was a nonrandomized clinical trial. PARTICIPANTS Seven eyes of six patients with severe chemical (n = 5) and thermal (n = 2) burns were studied. INTERVENTION Eyes were treated with excision of cicatricial tissues followed by a placement of amniotic membrane on the sclera. Transplantation of limbal grafts from an opposite eye (n = 4) or from donor eyes preserved at -80 degrees C (n = 2) was performed simultaneously. MAIN OUTCOME MEASURES Reconstruction of ocular surface epithelia and visual acuity were measured. RESULTS With the mean observation period of 53.3 weeks, central corneal epithelium was reconstructed successfully in all eyes. Neither amniotic membrane nor limbal grafts were rejected. A persistent epithelial defect developed in one eye, which was treated successfully by tarsorrhaphy. After surgery, the corneal epithelium showed normal arrangements on specular microscopy, and its barrier function recovered to seminormal. Corrected visual acuity markedly improved in each eye. Regenerated conjunctiva on the amniotic membrane was stable and uninflammed with minimum-to-mild scarring. Slight recurrence of conjunctivalization was noted in three eyes. However, because these eyes were stable and central cornea was clear, no further surgery was needed. CONCLUSIONS Amniotic membrane transplantation promotes normal conjunctival epithelialization while suppressing fibrosis formation. The procedure, especially when performed with limbal autograft transplantation, appears to be effective for the treatment of chemical or thermal burns of the ocular surface.
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Shimmura S, Yang HY, Bissen-Miyajima H, Shimazaki J, Tsubota K. Posterior corneal protrusion after PRK. Cornea 1997; 16:686-8. [PMID: 9395880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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271
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Huang BM, Stocco DM, Li PH, Yang HY, Wu CM, Norman RL. Corticotropin-releasing hormone stimulates the expression of the steroidogenic acute regulatory protein in MA-10 mouse cells. Biol Reprod 1997; 57:547-51. [PMID: 9282989 DOI: 10.1095/biolreprod57.3.547] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We have previously demonstrated that corticotropin-releasing hormone (CRH) treatment of MA-10 mouse Leydig tumor cells results in a dose-dependent stimulation of progesterone production. In view of this observation we wished to determine the effects of CRH on the synthesis of the steroidogenic acute regulatory (StAR) protein in these cells. StAR is a steroidogenic tissue-specific, hormone-induced, rapidly synthesized protein previously shown to be involved in the acute regulation of steroidogenesis, probably by promoting the transfer of cholesterol to the inner mitochondrial membrane and the cytochrome P450 side-chain cleavage enzyme. Treatment of MA-10 cells with the cAMP analogue dibutyryl cAMP (dbcAMP) resulted in a dose- and time-dependent increase in the levels of StAR protein that reached a maximum at 800 microM dbcAMP and within a time period of 6 h. Further, treatment of MA-10 cells with CRH also resulted in a dose-dependent increase in the synthesis of the StAR protein with a maximal response observed at 1 microM. Slightly different from that observed with dbcAMP, the maximal response to 1 microM CRH was seen at 4 h following stimulation. These results indicate that the observed increase in steroid production in response to CRH in MA-10 Leydig tumor cells is similar to that previously seen with trophic hormone stimulation acting through the cAMP second messenger pathway, and that it occurs as a result of an increase in the synthesis of the StAR protein.
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Kriho VK, Yang HY, Moskal JR, Skalli O. Keratin expression in astrocytomas: an immunofluorescent and biochemical reassessment. Virchows Arch 1997; 431:139-47. [PMID: 9293896 DOI: 10.1007/s004280050080] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Several studies have shown that immunoenzymatic staining of formalin-fixed, paraffin-embedded astrocytomas with keratin antibodies frequently yields positive labelling, but no biochemical evidence of keratin expression in astrocytomas has been reported. We have investigated the presence of keratin in astrocytoma and normal brain tissues both by immunofluorescence on frozen sections and by 1D and 2D immunoblotting using seven monoclonal antibodies that, collectively, recognize most keratin polypeptides. Four of these antibodies did not stain neural tissues by immunofluorescence and were also negative by immunoblotting. The remaining three keratin antibodies stained normal brain and/or a high proportion of astrocytomas. Two of these three antibodies only stained glial fibrillary acidic protein (GFAP)-positive cells, while the third only stained GFAP-negative cells. 1D and 2D immunoblotting analysis showed that positive immunofluorescence staining of normal brain and/or astrocytomas seen with these three keratin antibodies was due to cross-reactivity with non-keratin proteins, such as GFAP. These results demonstrate that, contrary to earlier suggestions, keratin polypeptides are not frequently expressed in astrocytomas. Our studies also emphasize that keratin antibodies should be used cautiously for the differential diagnosis of undifferentiated gliomas from tumours of non-glial origin.
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273
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Kuhlman B, Yang HY, Boice JA, Fairman R, Raleigh DP. An exceptionally stable helix from the ribosomal protein L9: implications for protein folding and stability. J Mol Biol 1997; 270:640-7. [PMID: 9245593 DOI: 10.1006/jmbi.1997.1146] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The ribosomal protein L9 has an unusual structure comprising two compact globular domains connected by a 34 residue alpha-helix. The middle 17 residues of the helix are exposed to solvent while the first seven pack against and form part of the N-terminal domain, and the last ten form part of the C-terminal domain. Here we report results which show that a peptide corresponding to the central helix of L9 is monomeric in aqueous solution and >85% helical at 1 degrees C and 68(+/-7)% helical at 25 degrees C. This is considerably more helical than any other protein fragment studied to date. Another peptide corresponding to the middle 17 residues of the helix is monomeric and is 41(+/-4)% helical at 1 degrees C. Because the central helix has high intrinsic stability the globular N and C-terminal domains will likely be stabilized by their interactions with the helix. Therefore, the stability of the two terminal domains should not be completely independent because both domains gain stability from a shared structural element, the central helix. Also, the ability of the central helix to form native-like structure in isolation highlights a potential role for the helix in the early stages of the folding process.
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274
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Yang HY, Lieska N, Kriho V, Wu CM, Pappas GD. A subpopulation of reactive astrocytes at the immediate site of cerebral cortical injury. Exp Neurol 1997; 146:199-205. [PMID: 9225753 DOI: 10.1006/exnr.1997.6518] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We have identified an early-appearing intermediate filament-associated protein (IFAP-70/280 kDa) in radial glia and their immediate derivatives. This IFAP is absent in the adult CNS. In this study, we examined the reexpression of this early glial differentiation trait in rat reactive astrocytes induced by stab injury of the cerebrum. Double-label immunofluorescence microscopy demonstrated that by 36 h postlesion, IFAP-70/280 kDa was present in a few GFAP-positive astrocytes in the area adjacent to the wound. As the gliotic reaction progressed, the number of IFAP-positive reactive astrocytes increased and by 5-6 days postlesion, IFAP-70/280 kDa was present in most of the hypertrophied astrocytes in tissue immediately adjacent to the wound. By 8 days postlesion, while the number of IFAP-negative reactive astrocytes away from the wound diminished, the IFAP-containing reactive astrocytes close to the wound persisted. Concurrently, they began to change from a stellate form to an elongated shape, with their longitudinal axes radiating from the wound. The immunoreactivity of this IFAP started to diminish at 20 days postlesion, and by 30 days postlesion, it was not observed in the remaining gliotic cells. These results demonstrate that reactive astrocytes induced by stab-wound injury can be divided into two subtypes: persistent IFAP-70/280 kDa-containing cells which are close to the wound in the area of the glial scar and transient IFAP-70/280 kDa-negative cells which are farther from the wound. The reappearance of IFAP-70/280 kDa also suggests that some reactive astrocytes have the capacity to recapitulate early developmental stages.
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275
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Yang HY, Fujishima H, Toda I, Shimazaki J, Tsubota K. Lacrimal punctal occlusion for the treatment of superior limbic keratoconjunctivitis. Am J Ophthalmol 1997; 124:80-7. [PMID: 9222236 DOI: 10.1016/s0002-9394(14)71647-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE To test the hypothesis that superior limbic keratoconjunctivitis is caused by insufficient tear supply to the superior keratoconjunctiva. METHODS We used cautery and sutures to permanently occlude the lacrimal puncta of 11 patients (22 eyes) with superior limbic keratoconjunctivitis for whom topical treatment was ineffective. RESULTS All 11 patients (22 eyes) responded favorably to lacrimal punctal occlusion. After lacrimal punctal occlusion, rose bengal and fluorescein staining (both on a scale of 0 [no staining] to 9 [complete staining]) were reduced (mean +/- SD, 2.7 +/- 1.6 to 1.1 +/- 1.8 and 1.4 +/- 1.2 to 0.4 +/- 0.8, respectively). Impression cytology disclosed improvement of squamous metaplasia in the superior conjunctiva as well as increased goblet cells in nine of 13 eyes (69%) examined. Subjective symptoms improved in all 22 eyes (100%). CONCLUSIONS Improvement of local tear deficiency to the superior limbic portion by punctal occlusion was an effective treatment in this small series. Superior limbic keratoconjunctivitis might be caused by the insufficient local tear supply.
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