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Ryu JC, Kwon OS, Song YS, Yang JS, Park J. The effects of probenecid on the excretion kinetics of stanozolol, an anabolic steroid, in rats. J Appl Toxicol 1992; 12:385-91. [PMID: 1452971 DOI: 10.1002/jat.2550120605] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The pharmacokinetic behaviour and the mechanism of renal excretion of stanozolol (STZ), as affected by co-treatment with probenecid, were studied in male Sprague-Dawley rats. Pharmacokinetic parameters following intravenous (i.v.) administration of STZ (20 mg kg-1 body wt.) were measured in both STZ-treated (control) and STZ plus probenecid-treated (treatment) groups. In order to assess the renal clearance of STZ, bolus doses of STZ and inulin (40 mg kg-1 body wt.) were injected i.v. either in the presence or absence of probenecid (40 mg kg-1 body wt.). The blood and urine concentrations of STZ were determined by capillary gas chromatography-mass spectrometry (GC-MS). In the probenecid treatment group, the area under the plasma disappearance and urinary excretion curves (AUC) of STZ were significantly decreased (P < 0.01) and the volume of distribution (Vd) and total clearance (CLt) were significantly increased statistically (P < 0.05 and P < 0.01, respectively). No remarkable differences in the urine flow rate, urine pH values, glomerular filtration rate (GFR) or renal clearance were observed in the treatment group. However, the clearance ratio in the treatment group was significantly increased from 11.72 to 17.27. From these results, it is suggested that the significant decrease of AUC, i.e. increase of disappearance of STZ in plasma by co-administration with probenecid, is due to the increase of the clearance ratio.
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Bang SH, Oh YS, Park HJ, Lee TK, Yang JS, Lee SM, Min KW, Park W. Evaluation of finger blood flow with Tc-99m MDP (methylene diphosphonate). Korean J Intern Med 1992; 7:94-101. [PMID: 1306078 PMCID: PMC4532110 DOI: 10.3904/kjim.1992.7.2.94] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND A variety of methods were used to establish objective diagnostic criteria of Raynaud's phenomenon. We intended to introduce another method, using radionuclide (Tc-99m methylene diphosphonate) scintigraphy, which is more objective, simple and economical than the past methods. METHODS The finger blood flow with radionuclide scintigraphy was evaluated in 10 patients of Raynaud's syndrome, 12 patients of connective disease without Raynaud's symptoms, and 20 normal persons. After immersing one hand in ice water (4 degrees C) for 30 seconds, the hand was exposed to 22 degrees C room air for 15 minutes, and then the patients received the intravenous (IV) bolus of 20 microCi of Tc-99m methylene diphosphonate (MDP). At the same time, scintigraphic image of both hands started with the region of interest, including the second, third, fourth and fifth fingers distal to the metacarpophalangeal (MCP) joints. Computer recording of the counts in the region of interest every 2 seconds for 310 seconds was started on IV bolus injection. RESULTS The 310 seconds cumulative digital blood flow ratio of cold exposed hand to room air exposed hand was significantly lower in Raynaud's group (p < 0.001), and the ratio of initial slope of activity curve was also lower in the Raynaud's group (p < 0.001). Of the 8 patients showing Raynaud's syndrome, 4 patients of scleroderma and 1 patient of multiple myeloma showed no improvement of finger blood flow in the cold exposed hand after 2 weeks of pharmacological therapy, but 1 patient of mixed connective tissue disease, 1 patient of Behcet's syndrome and 1 patient of SLE showed much improved finger blood flow after combined administration of vasodilator, calcium channel blockers and antiplatelet drugs. CONCLUSIONS The evaluation of finger blood flow with 99mTc-MDP could be considered to be one of the simple, economical and new methods that can be used in the follow-up, objective assessment of therapeutic effect, and giving an aid in the study of the pathophysiology of the Raynaud's phenomenon.
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Yang JS, Chu Q, Deng WW, Wu DM. Endobronchial leiomyoma. Chin Med J (Engl) 1992; 105:340-2. [PMID: 1618019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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204
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Zucker-Franklin D, Yang JS, Grusky G. Characterization of glycoprotein IIb/IIIa-positive cells in human umbilical cord blood: their potential usefulness as megakaryocyte progenitors. Blood 1992; 79:347-55. [PMID: 1370385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Abstract
A need for hematopoietic stem cells, particularly cells destined to enter the megakaryocyte (MK) series, prompted phenotypic analysis of mononuclear leukocytes in human cord blood. To this end, immunohistochemical, flow cytometric, and ultrastructural techniques were used. The immunogold silver enhancement method (IGS) for the detection of the MK-specific glycoprotein (GP) IIb/IIIa epitopes combined with a monocyte-specific stain for alpha-naphthyl butyrate esterase proved to be superior to flow cytometry (FACS) for precise quantitation of cell types in each sample. Immunoelectron microscopy afforded a description of distinctions between precursors bearing GPIIb/IIIa epitopes and other stem cells of the myeloid series. The number of presumed MK progenitors was surprisingly high, averaging 1.8% +/- 1.3% (range, 0.2% to 4.6%) by IGS and 4.1% +/- 3.0% (range, 0.2% to 9.3%) by FACS analysis. The occurrence of GPIIb/IIIa-positive denuded MK nuclei in cord blood was of interest, but was too small to affect these data. These observations should advocate a greater use of cord blood for restitution of MK/platelet-lineage-depleted patients as well as for experimental studies concerned with MK differentiation.
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Cheng YC, Yang JS. Erratum: Enhancement of the van der Waals energy between an atom and a cylindrical surface: Application to the edges of stepped surfaces. PHYSICAL REVIEW. B, CONDENSED MATTER 1991; 44:13175. [PMID: 10021555 DOI: 10.1103/physrevb.44.13175.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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206
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Yang JS, Su YL, Wang YL, Feng XZ, Yu DQ, Liang XT. Two Novel Protoilludane Norsesquiterpenoid Esters, Armillasin and Armillatin, from Armillaria mellea. PLANTA MEDICA 1991; 57:478-80. [PMID: 17226185 DOI: 10.1055/s-2006-960176] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Two novel protoilludane norsesquiterpenoid esters, named armillasin and armillatin, have been isolated from the artificially cultured mycelium of ARMILLARIA MELLEA (Tricholomataceae). Their structures have been assigned on the basis of a detailed study of their spectral data. Their relative configurations were established from the nuclear Overhauser effects.
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Abstract
Kawasaki disease is a multisystem disorder with varying clinical expression. This is a report on one case of Kawasaki disease which during its clinical course developed facial nerve palsy and spontaneous recovery without specific treatment. It is hoped that this report will serve to remind physicians of the association of facial nerve paralysis with Kawasaki disease.
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208
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Yang JS, Sladky JT, Kallen RG, Barchi RL. TTX-sensitive and TTX-insensitive sodium channel mRNA transcripts are independently regulated in adult skeletal muscle after denervation. Neuron 1991; 7:421-7. [PMID: 1654949 DOI: 10.1016/0896-6273(91)90294-a] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The expression of mRNA encoding the TTX-sensitive (SkM1) and TTX-insensitive (SkM2) voltage-dependent sodium channels in adult skeletal muscle is independently regulated. In normal skeletal muscle, only the SkM1 message is expressed and the level varies with muscle fiber type. After surgical denervation, the steady-state SkM1 mRNA level declines transiently, but returns to control levels within 5 days. Expression of SkM2 transcripts is markedly activated, reaching a peak 3 days after axotomy and then declining to a maintained level at approximately 30% of peak. Chemical denervation with botulinum toxin results in higher levels of SkM2 mRNA, which by 7 days posttreatment are 7-fold greater than levels in paired axotomized muscles. SkM2 expression subsequently declines as functional reinnervation appears. Quantal acetylcholine release appears to play a major role in suppression of SkM2 expression in adult innervated or reinnervated muscle, whereas nonquantal factors in toxin-treated, but not axotomized, muscle may sustain high level SkM2 mRNA expression.
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209
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Yang JS, Hsieh RP, Shen MC. [A comparative study of antinuclear antibody measurement using different cells as nuclear substrates]. ZHONGHUA MINGUO WEI SHENG WU JI MIAN YI XUE ZA ZHI = CHINESE JOURNAL OF MICROBIOLOGY AND IMMUNOLOGY 1991; 24:299-310. [PMID: 1818799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In an attempt to evaluate possible variations in the antinuclear antibody (ANA) titers resulting from nuclear substrate difference, we measured the ANA titer of 104 normal subjects using substrates from mouse liver cell (MLC) and HEp-2 cell (CSI, USA). We also performed similar experiments on 50 sera from 50 patients with rheumatic disease using mouse liver cell, HEp-2 cell (CSI), HEp-2 cell (AFT, Japan), and HEp-2 cell (AI, USA) as substrates. The ANA titer assay using HEp-2 cell (CSI), which is routinely used in our laboratory, was regarded as the reference method. The results showed that when HEp-2 (CSI) was used, 98.1% normal subjects had ANA titer lower than 1:320, therefore a cut-off value of 1:320 was used. While using the MLC method, 96.2% normal subjects had ANA titer lower than 1:80, and the cut-off value was set at 1:80 accordingly. The geometric mean ANA titers of the 50 sera from 50 rheumatic disease patients were 676 for HEp-2 cell (CSI), 503 for HEp-2 cell (AFT), 368 for HEp-2 cell (AI), and 265 for MLC, respectively. Although statistically significant difference (p less than 0.05) in geometric mean titer existed between reference method and the other 3 methods, the latter 3 methods still had good sensitivity (97.2% for HEp-2 cell (both AFT and AI); 91.7% for MLC), and specificity (100% for HEp-2 cell (both AFT and AI); 71.4% for MLC) for selecting out sera with abnormal ANA titer. We also evaluated the relationships between ANA titer and anti-double stranded DNA antibody (anti-dsDNA) concentration in another 210 sera from 151 patients with rheumatic disease. Statistically, there is no distinct correlation between anti-dsDNA and ANA of all fluorescence staining patterns except for peripheral pattern, in which case a significant correlation could be demonstrated.
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210
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Bao LL, Yang JS, Xiao J, Guo ZT. Pseudoxanthoma elasticum. A report of 5 cases in one family. Chin Med J (Engl) 1991; 104:237-43. [PMID: 2065538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Five cases of pseudoxanthoma elasticum (PXE) found in one family are reported. The hereditary pattern is probably of autosomal dominant type 2. In the fundi of all the 5 cases, mottlings of the retinal pigment epithelium or orange skin-like lesions in both eyes which are of significant diagnostic importance are seen. The fundus changes are more prominent when skin lesions are typical. Under electron and light microscope, the pathological changes of clinically typical and atypical lesions show similar characteristics of this disorder. Remarkable calcification of elastic fibers with abnormal contour and fragmentation, destruction of mitochondria of fibroblasts and a great number of mast cells leaning against fibroblasts are the chief findings in the histochemically stained specimens. The pathogenetic mechanism of this disorder is possibly dystrophy of elastic fibers with its inherent nature of being easily calcified. Involvement of autoimmune factors in the pathogenesis is quite possible.
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Bao LL, Guo LL, Li SN, Xiao J, Yang JS, Bai LR, Ye PM, Guo ZT, Liu DW. A family with Fabry's disease. Ocular manifestations and transmission electron microscopic examination of a skin lesion biopsy. Chin Med J (Engl) 1990; 103:134-41. [PMID: 2118030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
A family with Fabry's disease including 2 hemizygotes and 3 heterozygotes is reported. The ocular manifestations include tortuosity of conjunctival vessels, Fabry's deposits underlying the anterior capsule of the lens and the whorl-like corneal dystrophy. Foam cells or mulberry cells in the urinary sediment and varying numbers of high electron-dense inclusions in the cytoplasm of endothelial cells in skin lesions are also important in diagnosing this disease. The concentrations of lipid peroxide in the sera of 2 hemizygotes in this report were higher than normal, possibly due to the patients weak ability of anti-oxygenation and malfunction of cells whose plasma membranes are easily attacked by free oxygen radicals. The biochemical and pathological changes, diagnosis, treatment, genetics and prevention of the disease are discussed.
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Cheng YC, Yang JS. Enhancement of the van der Waals energy between an atom and a cylindrical surface: Application to the edges of stepped surfaces. PHYSICAL REVIEW. B, CONDENSED MATTER 1990; 41:1196-1199. [PMID: 9993818 DOI: 10.1103/physrevb.41.1196] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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213
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Yang JS, Chen YW, Feng XZ, Yu DQ, He CH, Zheng QT, Yang J, Liang XT. Isolation and structure elucidation of armillaricin1. PLANTA MEDICA 1989; 55:564-5. [PMID: 17262479 DOI: 10.1055/s-2006-962096] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
From the petroleum ether extracts of the artificially cultured mycelium of ARMILLARIA MELLEA, a novel sesquiterpenoid aromatic ester named armillaricin has been isolated by silica gel column chromatography. Its structure was deduced from spectral data and confirmed by single-crystal X-ray analysis.
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214
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Yang JS, Su YL, Wang YL, Feng XZ, Yu DQ, Cong PZ, Tamai M, Obuchi T, Kondoh H, Liang XT. Isolation and structures of two new sesquiterpenoid aromatic esters: armillarigin and armillarikin1. PLANTA MEDICA 1989; 55:479-81. [PMID: 17262464 DOI: 10.1055/s-2006-962070] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The continued investigation of the mycelial extract of ARMILLARIA MELLEA (Vahl.ex Fr.) Quel. (Tricholomelaceae) led to the isolation of two new sesquiterpenoid aromatic esters, named armillarigin ( 1) and armillarikin ( 2). Their structures were elucidated on the basis of spectral data and chemical transformation.
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215
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Turner DM, Ransom RW, Yang JS, Olsen RW. Steroid anesthetics and naturally occurring analogs modulate the gamma-aminobutyric acid receptor complex at a site distinct from barbiturates. J Pharmacol Exp Ther 1989; 248:960-6. [PMID: 2539464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The steroid anesthetic alphaxalone and a series of naturally occurring analogs were compared in potency and efficacy with each other and the hypnotic barbiturate pentobarbital for interaction with gamma-aminobutyric acid (GABA) receptors:binding sites in rat brain membranes and functional activity in 36Cl- flux measurements with rat hippocampal slices. The steroids enhanced [3H]muscimol binding to GABA receptor sites, enhanced [3H] flunitrazepam binding to benzodiazepine receptors and inhibited [35S]t-butyl bicyclophosphorothionate binding to picrotoxin/convulsant binding sites on the GABA receptor-chloride channel complex. The same steroids that were active in modulating the binding of ligands to the various receptor sites on the GABA receptor complex at micromolar concentrations enhanced muscimol-stimulated 36Cl- flux in rat hippocampal slices. The steroids, like the barbiturates, increased the maximal response to muscimol but produced little or no potentiation of basal 36Cl- flux in the absence of GABA agonist. Although the effects of steroids and barbiturates were similar, separate sites of action were demonstrated conclusively by the observation that the two classes of compounds, when included together, gave additive or synergistic effects on binding, as well as on 36Cl- flux in the absence of GABA agonist. Structure-activity studies showed that the synthetic steroid anesthetic alphaxalone was the most potent compound tested, followed by the naturally occurring steroids tetrahydro-deoxycorticosterone, allo-tetrahydrocorticosterone, cis-androsterone and 5 alpha-androstan-17 beta-ol-3-one. The ability of several naturally occurring steroids to enhance GABA-mediated inhibition in the brain suggests the possibility of an endogenous steroid modulator of neuronal function.
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Abstract
We describe a simplified technique for the rapid and specific detection of antigenic determinants within a mixed population of antigens. Each determinant develops its own characteristic color in a single Western blot or dot blot. This multicolor immunostaining technique can be achieved with as little as a one-step incubation, involving a mixture of different primary and developing antibodies, and a one-step substrate reaction, involving a mixture of different substrates. The time required can be reduced to short periods of time, ranging from minutes to about 1 h. This can represent an increase in the speed of detection by one to two orders of magnitude when compared with conventional methods. The simplified protocols may facilitate the automation of routine analyses.
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217
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Zhou XG, Wang YC, Yu BM, Shen YX, Chen ZR, Lin LH, Yang JS, Zhang DS, Ding QG, Ma L. [Route and preparation of 5-Fu administration as preoperative adjuvant chemotherapy in rectal cancer. II. Morphologic, ultrastructural and histochemical changes of the cancer cells after intrarectal and intravenous 5-Fu administration]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 1988; 10:220-3. [PMID: 3219984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
From March 1981 to October 1985, 5-Fu was preoperatively given to 65 Dukes B and C rectal cancer patients (intrarectal suppository 40 and emulsion 20, intravenous 5). The results indicated that after intrarectal administration, marked changes and destruction of the cancer cells in morphology were observed in 40% of the resected rectal specimens for suppository and in 45% for emulsion; marked retrograde degeneration in ultrastructure was found in 47.5% for suppository and in 50% for emulsion; DNA synthesis was obviously reduced in 63% for suppository and in 75% for emulsion. It is suggested that the emulsion be a better preparation. No obvious changes or destruction in morphology and ultrastructure were observed in cancer cells treated by intravenous drip of high dose 5-Fu though leukopenia below 4000 was found in 2/5. However, it was 0/60 by rectal administration. This implies that the intrarectal route is more rational than the conventional intravenous route. This study presents an alternate supplementary treatment in addition to radiotherapy for the reduction of postoperative local recurrence of Dukes B and C rectal cancers.
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218
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Yang JS, Yu DQ, Liang XT. [Kumujansine and kumujantine, two new dimeric beta-carboline alkaloids from Picrasma quassioides (D. Don.) Benn]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1988; 23:267-72. [PMID: 3176979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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219
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Li GY, Yang JS. [Review of the studies on the metabolites of fungi]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1988; 23:224-38. [PMID: 3048041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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220
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Wu BQ, Fang WG, Zheng J, Sun YK, Wang JL, Zhao XS, Yang JS, Lu CP, Sun J, Xu QM. [In vivo metastasis of human tumor transplant in T and NK cell immune-deficient mice]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 1988; 10:1-3. [PMID: 3262047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Beige-nude mice with combined T and NK cell deficiency were produced by introducing "nu" gene into the beige mice of C57BL/6 background. The beige-nude mice were characterized by morphological features, level and activity of the NK cell in spleen and peripheral blood. NK cell level of the beige-nude mice was higher than the beige mice and similar to the ordinary nude mice though its NK cell activity was markedly lower than the nude mice. Human lung adenocarcinoma (PAa) was transplanted subcutaneously to the beige-nude mice and nude mice of BALB/cA background. No metastasis was found in BALB/cA nude mice (0/7), while in beige-nude mice, spontaneous lymph node metastasis rate was 36.3% (4/11). It should be noted that the transplanted PAa metastasized to lungs, which had never been seen in BALB/cA nude mice in previous experiments. The increase of metastatic rate is correlated with the relative low NK cell activity of the beige-nude mice. Our observation is that the beige-nude mice could be a suitable experimental model for in vivo study on metastatic behavior of the human tumors.
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221
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Yang JS, Lu X, Zhang WN. [Experimental study on the factors influencing left ventricular function in post myocardial infarction]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 1987; 15:294-7, 312. [PMID: 3440436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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222
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Wang JH, Yang JS, Lu X. [Changes and analysis of cardiac performance after ligation of the coronary arteries in rats]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 1987; 15:233-6, 248. [PMID: 3440427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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223
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Yang JS, Olsen RW. gamma-Aminobutyric acid receptor binding in fresh mouse brain membranes at 22 degrees C: ligand-induced changes in affinity. Mol Pharmacol 1987; 32:266-77. [PMID: 3039341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Binding of [3H]muscimol to mouse brain gamma-aminobutyric acid receptors has been assayed under more physiological conditions (never-frozen membranes, 22 degrees) than in previous studies (0-4 degrees on frozen-thawed membranes). Binding affinities were lower and agreed more closely with physiological dose response curves. In addition, heterogeneity in affinity was still present, apparently due to a mixture of non-interconvertible subpopulations and ligand-induced changes in kinetics. Super-high affinity sites (Kd less than 10 nM) observed in frozen membranes were not observed in fresh membranes under equilibrium binding conditions, and high affinity sites (Kd congruent to 25 nM) seen at 0 degree had lower affinity (Kd congruent to 250 nM) at 22 degrees. Despite an apparent best fit single-component Scatchard plot for the latter data, cold ligand displacement and association and dissociation rates demonstrated heterogeneity of affinities. Pentobarbital greatly increased the amount of high affinity sites at the expense of low affinity sites in equilibrium binding at 0 degree and slightly increased affinity at 22 degrees. The kinetics of [3H]muscimol association at 22 degrees (kapp = 1-2/min) were virtually independent of the ligand concentration, suggesting either negative cooperativity or an agonist binding-dependent receptor isomerization. Dissociation triggered by addition of excess cold ligand to membranes equilibrated with [3H]muscimol at different concentrations revealed two off-rates with t1/2 values of under 10 sec and 1-3 min; unexpectedly, the ratio of these two populations did not vary with ligand concentration but was constant at 50:50. Dissociation triggered by infinite dilution gave two off-rates, but the slowest component had a t1/2 of about 20 min; including cold muscimol in the dilution buffer increased the off-rate toward that observed in the excess cold ligand method (t1/2 = 1-2 min). The very slow off-rate was only observed following removal of agonist from a previously occupied receptor and suggests receptor isomerization into a high affinity state; this state is similar to that observed at 0 degree. Pentobarbital also favored the production of the receptor state showing very slow [3H]muscimol dissociation upon infinite dilution, opposing the action of high receptor occupancy with cold muscimol. Thus, [3H]muscimol-binding sites observed at 22 degrees with fresh membranes do not show artificially high affinity and have a Kd of 0.2-0.3 microM, closer to the EC50 for chloride channel activation (approximately 2-3 microM and 0.4 microM with pentobarbital).(ABSTRACT TRUNCATED AT 400 WORDS)
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Yang JS, Park CK, Rim KS. Successful removal of a large stone from the common bile duct by endoscopic papillotomy and lithotripsy. Korean J Intern Med 1987; 2:282-4. [PMID: 3154841 PMCID: PMC4534946 DOI: 10.3904/kjim.1987.2.2.282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
A previously cholecystectomized man presented on endoscopic retrograde cholangiography with a large stone (6×2×2 cm) in the common bile duct. The patient refused surgical removal of the stone, so although endoscopic papillotomy was contrainicated, it was attempted. Herein is presented a case report of successful removal of a large stone by endoscopic papillotomy and lithotripsy with no significant complications.
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225
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Yang JS, Olsen RW. gamma-Aminobutyric acid receptor-regulated 36Cl- flux in mouse cortical slices. J Pharmacol Exp Ther 1987; 241:677-85. [PMID: 3033222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
An improved neurochemical assay for gamma-aminobutyric acid (GABA) function has been developed using tracer-radioactive chloride efflux in mouse cortical slices. Careful maintenance of the brain slice viability resulted in a 3-fold stimulation of 36Cl- efflux rate by the GABA agonist muscimol (EC50 = 3 microM), comparable to electrophysiologic and other chloride flux preparations. The shape of the muscimol dose-response curve was shallow, suggestive of negative cooperativity or heterogeneous receptors, but tissue uptake of agonist, possible diffusion barriers and apparent functional desensitization complicated these results. The response to muscimol was inhibited by GABAA receptor antagonists such as RU5135 and was enhanced by barbiturates and benzodiazepines. As observed previously, barbiturates stimulated 36Cl- efflux rate on their own and potentiated the response (potency and maximal effect) to muscimol in a stereospecific and picrotoxin-sensitive manner. Benzodiazepine receptor ligands alone did not alter 36Cl- flux, but agonists such as flunitrazepam enhanced the response to muscimol, an effect sensitive to the antagonist Ro15-1788. The inverse agonist methyl 6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate did not inhibit muscimol-activated 36Cl- flux. The anthelminthic-insecticide avermectin B1a stimulated 36Cl- flux by itself, and this response was apparently additive with that of muscimol. This brain slice chloride flux assay is therefore suitable for the assessment of activity including dose-response curves for GABAA agonists, antagonists and modulators including benzodiazepines.
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