51
|
Mahoney T, Kuo YH, Topilow A, Davis JM. Stage III colon cancers: why adjuvant chemotherapy is not offered to elderly patients. ARCHIVES OF SURGERY (CHICAGO, ILL. : 1960) 2000; 135:182-5. [PMID: 10668878 DOI: 10.1001/archsurg.135.2.182] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
HYPOTHESIS Adjuvant chemotherapy is not offered to elderly patients with stage III colon cancer. DESIGN A retrospective review of hospital and office records. SETTING A suburban community hospital. PATIENTS The medical records of 69 patients with stage III colon cancer were reviewed. All identified from the Tumor Registry at Jersey Shore Medical Center, Neptune, NJ, were included in this study. RESULTS Thirty-five patients (51%) did not receive adjuvant chemotherapy. After adjusting for age, women were 5.8 times less likely to receive chemotherapy (P = .002). Patients not receiving chemotherapy were significantly older (78.7 vs 70.4 years; P = .003) than those who received adjuvant chemotherapy. There was no relation found between the year of diagnosis and the administration of chemotherapy. There were 4 major reasons for not receiving chemotherapy: (1) not offered (n = 12, 34%), (2) refused (n = 11, 31%), (3) too old (n = 7, 20%), and (4) significant concomitant disease (n = 5, 14%). CONCLUSIONS A large group of elderly patients who had been surgically treated for colon cancer and who were eligible for adjuvant chemotherapy either were not referred for treatment or refused treatment. This suggests a bias on the part of surgeons, primary care physicians, and patients against the use of chemotherapy in elderly patients.
Collapse
|
52
|
|
53
|
Kuo YH, Fabiani JN, Mohamed AS, Couetil JP, Lévy M, Gutmann L, Carpentier AF, Bélec L. Decreasing occupational risk related to blood-borne viruses in cardiovascular surgery in Paris, France. Ann Thorac Surg 1999; 68:2267-72. [PMID: 10617015 DOI: 10.1016/s0003-4975(99)01051-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND Surgeons face the risk of patient-to-physician transmission of blood-borne viruses. This risk is related to the seroprevalence of the viruses in the patient population. METHODS The seroprevalence of the human immunodeficiency virus, hepatitis B virus, and hepatitis C virus were determined in cardiovascular patients at Hôpital Broussais in Paris, France, over a 5-year period (1994 to 1998). RESULTS Hepatitis C virus is the most prevalent virus in the patient population, whereas human immunodeficiency virus is the least frequent. The seroprevalence of hepatitis C virus and human immunodeficiency virus has decreased over time, whereas hepatitis B virus has remained constant. We apply the seroprevalence data to a mathematical model to estimate the occupational risk of seroconversion faced by surgeons over the length of their career. Our results show that the principal risk faced by the surgeon arises from hepatitis B virus and hepatitis C virus. The decreasing seroprevalence of the hepatitis C virus has resulted in a decrease in the occupational risk. CONCLUSIONS The probability of becoming infected with a blood-borne virus over the career of the surgeon is notable. The greatest occupational risk to the surgeon is from the hepatitis viruses and not HIV.
Collapse
|
54
|
Chen CC, Chen HY, Shiao MS, Lin YL, Kuo YH, Ou JC. Inhibition of low density lipoprotein oxidation by tetrahydrofurofuran lignans from Forsythia suspensa and Magnolia coco. PLANTA MEDICA 1999; 65:709-711. [PMID: 10630110 DOI: 10.1055/s-1999-14093] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Based on the inhibition of Cu(2+)-induced LDL oxidation as marker, the major antioxidants in the fruits of Forsythia suspensa and the stems of Magnolia coco were identified. Of these bioactive tetrahydrofurofuran lignans, pinoresinol, phillygenin, and syringaresinol were more potent than probucol. Sesamin and fargesin, which do not contain phenol groups, were found much less active.
Collapse
|
55
|
Lin YL, Tsai YL, Kuo YH, Liu YH, Shiao MS. Phenolic compounds from tournefortia sarmentosa. JOURNAL OF NATURAL PRODUCTS 1999; 62:1500-3. [PMID: 10579860 DOI: 10.1021/np9901332] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Three new isoprenylbenzenes, tournefolins A (1), B (2), and C (3), and two new 2-ethoxy-4,5-dihydroxybenzoyl compounds, 4 and 5, together with the known compounds, salicylic acid and allantoin, were isolated from the stems of Tournefortia sarmentosa. The structures of new compounds were elucidated as 2-(4beta-methyltetrahydrofuran-2alpha-yl)-5-(4beta-methyltetrahydrofu ran-2beta-yl)-1,4-dihydroxybenzene (1), methyl 5-(5-hydroxy-2-methoxyphenyl)-3-furoate (2), methyl 5-(2, 5-dihydroxyphenyl)-3-furoate (3), 2-ethoxy-4,5-dihydroxybenzaldehyde (4), and 2-ethoxy-4,5-dihydroxybenzoic acid (5), on the basis of spectral and chemical methods. The relative configuration of 1 was determined by single-crystal X-ray crystallography.
Collapse
|
56
|
Kuo YH, Hamer RM. Fetal amino acid and enzyme levels with maternal smoking. Obstet Gynecol 1999; 94:480-1. [PMID: 10472883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
|
57
|
Chen HY, Shiao MS, Huang YL, Shen CC, Lin YL, Kuo YH, Chen CC. Antioxidant principles from Ephemerantha lonchophylla. JOURNAL OF NATURAL PRODUCTS 1999; 62:1225-1227. [PMID: 10514302 DOI: 10.1021/np990025f] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
One dihydrostilbene and three phenanthrene antioxidants were isolated from an ethanolic extract of the Chinese herbal Ephemerantha lonchophylla. One of these compounds, ephemeranthone (4) is a new natural product. Denbinobin (1) and 3-methylgigantol (3) have been previously isolated from this plant, and 3-ethoxy-5-hydroxy-7-methoxy-1,4-phenanthraquinone (2) is an artifact. The structures of these compounds were determined by spectroscopic analysis. The antioxidative activities for inhibiting human low density lipoprotein oxidation in vitro of compounds 1-4 were determined, and only 4 was active (5.3 times that of probucol).
Collapse
|
58
|
Ikegami F, Yamamoto A, Kuo YH, Lambein F. Enzymatic formation of 2,3-diaminopropionic acid, the direct precursor of the neurotoxin beta-ODAP, in Lathyrus sativus. Biol Pharm Bull 1999; 22:770-1. [PMID: 10443484 DOI: 10.1248/bpb.22.770] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The enzymatic breakdown of beta-(isoxazolin-5-on-2-yl)-L-alanine (BIA) with formation of 2,3-diaminopropionic acid (DAPA), the direct precursor of the neurotoxin beta-ODAP in Lathyrus sativus, was confirmed in vitro. Some properties of the enzyme responsible for the biosynthesis of DAPA are described.
Collapse
|
59
|
Kuo YH, Li SY, Wu MD, Huang RL, Yang Kuo LM, Chen CF. A new anti-HBeAg lignan, kadsumarin A, from Kadsura matsudai and Schizandra arisanensis. Chem Pharm Bull (Tokyo) 1999; 47:1047-8. [PMID: 10434407 DOI: 10.1248/cpb.47.1047] [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: 12/30/2022]
Abstract
A new C18 dibenzocyclooctadiene lignan, kadsumarin A (1) was isolated from Kadsura matsudai Hayata and Schizandra arisanensis Hayata. The anti-HBeAg test revealed that kadsumarin A had activity at a concentration of 40 micrograms/ml (= 90.1 microM). Its structural elucidation by spectral analysis was discussed in this note.
Collapse
|
60
|
Kuo YH, Juang CJ. Sympathetic ophthalmia associated with cyclitis: case report. CHANGGENG YI XUE ZA ZHI 1999; 22:328-33. [PMID: 10493043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
We present a case of sympathetic ophthalmia. A 41-year-old man suffered a penetrating injury to his right eye. Six weeks after the injury he complained of photophobia and redness in his left eye. Visual acuity without correction was: right eye (RE), no light perception; and left eye (LE), 1.0. Ocular examination of the left eye revealed a shallow anterior chamber and mildly elevated intraocular pressure (25 mmHg). An initial diagnosis of narrow angle glaucoma was made and antiglaucomatous agents were prescribed. One month after diagnosis the vision in his left eye suddenly dropped to 0.04. Ocular examination showed annular serous retinal detachment and scattered yellow-white lesions (Dalen-Fuchs Nodules). Under the diagnosis of sympathetic ophthalmia, high dose intravenous corticosteroid (methylprednisolone, 200 mg daily) and subtenon dexamethasone (4 mg/0.8 cc) were used. Ten days after beginning treatment the vision improved to 0.1 but the retinal detachment was not sealed completely. Oral prednisolone (100 mg daily) and cyclosporine (125 mg bid) therapy replaced the intravenous corticosteroids. The serum level of Cyclosporine was 118 ng/ml. After 3 months the vision improved to 0.6 and the retinal detachment subsided. Renal function and hematocrit status were monitored closely and no abnormal conditions were noted.
Collapse
|
61
|
Huang SY, Kuo YH, Lee WC, Tsou HL, Lee YP, Chang HL, Wu JJ, Yang PC. Substantial decrease of heat-shock protein 90 precedes the decline of sperm motility during cooling of boar spermatozoa. Theriogenology 1999; 51:1007-16. [PMID: 10729022 DOI: 10.1016/s0093-691x(99)00046-1] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The decline in boar semen quality after cryopreservation may be attributed to changes in intracellular proteins. Thus, the aim of the present study was to evaluate the change of protein profiles in boar spermatozoa during the process of cooling and after cryopreservation. A total of 9 sexually mature boars (mean age = 25.5+/-12.3 mo) was used. Samples for protein analysis were collected before chilling, after cooling to 15 degrees C, after cooling to 5 degrees C, following thawing after freezing to -100 degrees C, and following thawing after 1 wk of cryopreservation at -196 degrees C. Semen characteristics evaluated included progressive motility and the percentage of morphologically normal spermatozoa. Total proteins from 5x10(6) spermatozoa were separated and analyzed by SDS-PAGE. The results revealed that there was a substantial decrease of a 90 kDa protein in the frozen-thawed spermatozoa. Western blot analysis demonstrated that this protein was 90 kDa heat-shock protein (HSP90). Time course study showed that the decrease of HSP90 in spermatozoa initially occurred in the first hour during cooling to 5 degrees C. When compared with the fresh spermatozoa before chilling, there was a 64% decrease of HSP90 in spermatozoa after cooling to 5 degrees C. However, the motility and percentage of normal spermatozoa did not significantly decrease during this period of treatment. Both declined substantially as the semen was thawed after freezing from -100 degrees C. The results indicated that the decrease of HSP90 precedes the decline of semen characteristics. The length of time between a decrease of HSP90 and the decline in sperm motility was estimated to be 2 to 3 h. Taken together, the above results suggested that a substantial decrease of HSP90 might be associated with a decline in sperm motility during cooling of boar spermatozoa.
Collapse
|
62
|
Chang CI, Kuo YH. Two new lupane-type triterpenes from diospyros maritima. JOURNAL OF NATURAL PRODUCTS 1999; 62:309-310. [PMID: 10075769 DOI: 10.1021/np980217v] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Two new lupane derivatives, 3-(E)-coumaroylbetulinaldehyde (1) and 3-(E)-coumaroyl-28-palmitoylbetulin (2), have been isolated from the stems of Diospyros maritima. Their structures were determined by using spectral and chemical methods.
Collapse
|
63
|
Li YC, Kuo YH. Five new diterpenoids from the wood of Cunninghamia konishii. JOURNAL OF NATURAL PRODUCTS 1998; 61:997-1000. [PMID: 9722483 DOI: 10.1021/np980074c] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Five new diterpenes, 3beta-acetoxyabieta-8,11,13-trien-12-ol (1), 8alpha-hydroxy-13(16),14-labdadien-19-al (2), 16-hydroxy-19-oxomanoyl oxide (3), 15-nor-14-oxo-8(17), 12-labdadiene-18-ol (4), and 15,16-bisnor-13-oxo-8(17), 11-labdadien-18-ol (5), were isolated from the wood of Cunninghamia konishii. Their structures were elucidated by 2D NMR spectroscopy and by chemical methods.
Collapse
|
64
|
Lin YL, Mei CH, Huang SL, Kuo YH. Four new sesquiterpenes from Petasites formosanus. JOURNAL OF NATURAL PRODUCTS 1998; 61:887-890. [PMID: 9677269 DOI: 10.1021/np970583z] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Four new eremophilane-type sesquiterpenes, petasones A (1) and B (2), S-petasitin (3), and petasinol (4), were isolated from the aerial parts of Petasites formosanus. Their structures were elucidated by spectroscopic and chemical methods as 3alpha-[(Z)-3-methylsulfinylacryloxy]eremophila-7(11), 9-dien-8-one; 3alpha-[(E)-3-methylsulfinylacryloxy]eremophila-7(11), 9-dien-8-one; 3alpha-[(Z)-3-methylthioacryloxy]-11-hydroxyeremophila -6, 9-dien-8-one; and 3alpha-[(E)-3-methylsulfinylacryloxy]-8beta-hydroxy eremophila-9, 11-diene, respectively.
Collapse
|
65
|
Kuo YH, Chen CH, Huang SL. New diterpenes from the heartwood of Chamaecyparis obtusa var. formosana. JOURNAL OF NATURAL PRODUCTS 1998; 61:829-831. [PMID: 9644078 DOI: 10.1021/np970531+] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
An abietane diterpene, 11,14-dihydroxy-8,11,13-abietatrien-7-one (1); a seco-abietane diterpene, obtuanhydride (2); and an isopimarane diterpene, 18,19-O-isopropylidene-18, 19-dihydroxyisopimara-8(14),15-diene (3) were isolated from the heartwood of Chamaecyparis obtusa var. formosana. The structures of these new compounds were elucidated by spectroscopic methods.
Collapse
|
66
|
Kuo YH, Chen CH. Sesquiterpenes from the leaves of Tithonia diversifolia. JOURNAL OF NATURAL PRODUCTS 1998; 61:827-828. [PMID: 9644077 DOI: 10.1021/np970530h] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Two new compounds, a germacrane sesquiterpene, 1-acetyltagitinin A (1), and a guaianane sesquiterpene, 8beta-isobutyryloxycumambranolide (2), were isolated from leaves of Tithonia diversifolia, together with two known compounds, methyl 3alpha-acetoxy-4alpha-hydroxy-11(13)-eudesmen-12-oa te and tagitinin A. The structures of compounds 1 and 2 were elucidated on the basis of spectral and chemical evidence.
Collapse
|
67
|
Shen YC, Chen CY, Kuo YH. A new taxane diterpenoid from Taxus mairei. JOURNAL OF NATURAL PRODUCTS 1998; 61:838-40. [PMID: 9644081 DOI: 10.1021/np970573y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
A new 11(15-->1)-abeotaxane diterpene, taxumairol K (1), has been isolated from the ethanolic extract of the roots of Formosan Taxus mairei (Lemee & Levl.) S. Y. Hu. The structure of 1 was determined as 9alpha-(benzoyloxy)-2alpha,4alpha- diacetoxy-5beta ,20-epoxy-1beta, 7beta,10beta,13alpha-tetrahydroxy-11(15-->1)-abeota xane on the basis of spectral analysis. Taxumairol K (1) exhibited mild cytotoxicity against HeLa tumor cells.
Collapse
|
68
|
Lin YL, Huang RL, Chang CM, Kuo YH. Two new puriniums and three new pyrimidines from Heterostemma brownii. JOURNAL OF NATURAL PRODUCTS 1997; 60:982-985. [PMID: 9358639 DOI: 10.1021/np970159y] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Two new puriniums, heteromines D (4) and E (5), and three new pyrimidines, heteromines F (6), G (7), and H (8), were isolated from the aerial parts of Heterostemma brownii Hay. Their structures were determined as 7,9-dimethyl-2-(N,N-dimethylamino)guaninium chloride, 7,9-dimethyl-2-(N-methylamino)guaninium chloride, 6-methoxy-4-(N-methylamino)-2-(N,N-dimethylamino)-5- (N-methylformamido)pyrimidine, 6-methoxy-2,4-bis(N-methylamino)-5-(N-methylformamido)pyrimidine, and 2-amino-6-methoxy-4-(N-methylamino)-5-(N-methylformamido)-pyrimidi ne, respectively.
Collapse
|
69
|
Kuo YH, Chang CI, Li SY, Chou CJ, Chen CF, Kuo YH, Lee KH. Cytotoxic constituents from the stems of Diospyros maritima. PLANTA MEDICA 1997; 63:363-365. [PMID: 9270382 DOI: 10.1055/s-2006-957703] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
One novel coumaric acid ester of lupeol, dioslupecin A (1), three naphthoquinones, 8'-hydroxyisodiospyrin (2), isodiospyrin (3), and plumbagin (4), three triterpenes, lupeol, lupenone and taraxerone, and four sterols, beta-sitosterol, stigmasterol, stigmast-4-en-3-one and ergosta-4,6,8(14),22-tetraen-3-one were isolated from the n-hexane extract of the stems of Diospyros maritima Blume. The structural determination of 1 was based on 1D and 2D NMR spectra (including 1H-1H COSY, 1H-13C COSY, and HMBC). All compounds were evaluated for in vitro cytotoxicity in 4 cancer cell lines. Compound 2 showed similar cytotoxicity against hepatoma (HEPA-3B, ED50 = 1.72 micrograms/ml), nasopharynx carcinoma (KB, ED50 = 1.85 micrograms/ml), colon carcinoma (COLO-205, ED50 = 2.24 micrograms/ml) and cervical carcinoma (HELA, ED50 = 1.92 micrograms/ml). Compounds 3 and 4 exhibited strong cytotoxicity against HEPA-3B, KB, COLO-205 and HELA (ED50 = 0.25, 1.81, 0.13 and 0.27 micrograms/ml for 3; ED50 = 0.87, 3.27, 0.56 and 0.35 micrograms/ml for 4, respectively.
Collapse
|
70
|
Chun TW, Carruth L, Finzi D, Shen X, DiGiuseppe JA, Taylor H, Hermankova M, Chadwick K, Margolick J, Quinn TC, Kuo YH, Brookmeyer R, Zeiger MA, Barditch-Crovo P, Siliciano RF. Quantification of latent tissue reservoirs and total body viral load in HIV-1 infection. Nature 1997; 387:183-8. [PMID: 9144289 DOI: 10.1038/387183a0] [Citation(s) in RCA: 1562] [Impact Index Per Article: 57.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The capacity of HIV-1 to establish latent infection of CD4+ T cells may allow viral persistence despite immune responses and antiretroviral therapy. Measurements of infectious virus and viral RNA in plasma and of infectious virus, viral DNA and viral messenger RNA species in infected cells all suggest that HIV-1 replication continues throughout the course of infection. Uncertainty remains over what fraction of CD4+ T cells are infected and whether there are latent reservoirs for the virus. We show here that during the asymptomatic phase of infection there is an extremely low total body load of latently infected resting CD4+ T cells with replication-competent integrated provirus (<10(7) cells). The most prevalent form of HIV-1 DNA in resting and activated CD4+ T cells is a full-length, linear, unintegrated form that is not replication competent. The infection progresses even though at any given time in the lymphoid tissues integrated HIV-1 DNA is present in only a minute fraction of the susceptible populations, including resting and activated CD4+ T cells and macrophages.
Collapse
|
71
|
Abstract
Four new triterpene compounds, celasdin-A, celasdin-C, anti-AIDS celasdin-B and cytotoxic maytenfolone-A, were isolated from Celastrus hindsii. The structural determination of maytenfolone-A, celasdin-A, celasdin-B and celasdin-C, as well as the structure-activity relationships of these new compounds and derivatives, are discussed. Maytenfolone-A was further confirmed by X-ray studies. Biological evaluation showed that Maytenfolone-A demonstrated cytotoxicity against hepatoma (HEPA-2B, ED50 = 2.3 micrograms ml-1) and nasopharynx carcinoma (KB, ED50 = 3.8 micrograms ml-1). Celasdin-B was found to exhibit anti-HIV replication activity in H9 lymphocyte cells with an EC50 of 0.8 microgram ml-1).
Collapse
|
72
|
Shen YC, Yang SW, Lin CS, Chen CH, Kuo YH, Chen CF. Zhankuic acid F: a new metabolite from a formosan fungus Antrodia cinnamomea. PLANTA MEDICA 1997; 63:86-8. [PMID: 17252333 DOI: 10.1055/s-2006-957614] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Zhankuic acid F (1), a new steroid acid, was isolated from the fruit bodies of Antrodia cinnamomea Chang & Chou, sp. nov. (Polyporaceae). The structure of 1 was elucidated by detailed analysis of 1D- and 2D-NMR spectra. Compound 1 appeared as a major product from the microbial transformation (Mucor racemosus) of zhankuic acid A (2).
Collapse
|
73
|
Ker JS, Kuo YH, Wen RC, Liu BD. Hardware implementation of CMAC neural network with reduced storage requirement. IEEE TRANSACTIONS ON NEURAL NETWORKS 1997; 8:1545-1556. [PMID: 18255755 DOI: 10.1109/72.641476] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The cerebellar model articulation controller (CMAC) neural network has the advantages of fast convergence speed and low computation complexity. However, it suffers from a low storage space utilization rate on weight memory. In this paper, we propose a direct weight address mapping approach, which can reduce the required weight memory size with a utilization rate near 100%. Based on such an address mapping approach, we developed a pipeline architecture to efficiently perform the addressing operations. The proposed direct weight address mapping approach also speeds up the computation for the generation of weight addresses. Besides, a CMAC hardware prototype used for color calibration has been implemented to confirm the proposed approach and architecture.
Collapse
|
74
|
Ko FN, Hsiao G, Kuo YH. Protection of oxidative hemolysis by demethyldiisoeugenol in normal and beta-thalassemic red blood cells. Free Radic Biol Med 1997; 22:215-22. [PMID: 8958147 DOI: 10.1016/s0891-5849(96)00295-x] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The purpose of this study was to evaluate the ability of demethyldiisoeugenol to protect normal and beta-thalassemic human red blood cells (RBCs) against oxidative damage in vitro. Oxidative hemolysis and lipid peroxidation of normal and beta-thalassemic human RBCs induced by aqueous peroxyl radical were suppressed by demethyldiisoeugenol in a concentration-dependent manner. The formation of proteins with high molecular weight and concomitant decrease of the low-molecular-weight proteins of RBCs challenge with aqueous peroxyl radical were inhibited by demethyldiisoeugenol. It also prevented the shortening of the Russell's viper venom (RVV)-clotting time mediated by prelytic radical-treated RBCs. In contrast, demethyldiisoeugenol inhibited oxidative hemolysis but not those metHb and ferrylHb formations caused by hydrogen peroxide (H2O2) in normal RBCs. Furthermore, demethyldiisoeugenol did not prevent the consumption of the cytosolic antioxidant, glutathione (GSH), in radical-treated RBCs. It also did not cause of a loss of sulfhydryl group during incubation with GSH. However, the diphenyl-2-picrylhydrazyl (DPPH) scavenging activity of demethyldiisoeugenol was dramatically increased in the presence of GSH. These results imply that demethyldiisoeugenol can regenerate from its oxidized form to its active reduced form in the presence of GSH. It may be useful in diminishing oxidative damage to pathological RBCs.
Collapse
|
75
|
Chen HC, Chou CK, Kuo YH, Yeh SF. Identification of a protein kinase C (PKC) activator, daphnoretin, that suppresses hepatitis B virus gene expression in human hepatoma cells. Biochem Pharmacol 1996; 52:1025-32. [PMID: 8831721 DOI: 10.1016/0006-2952(96)00420-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We examined the antiviral activity of a crude extract prepared from a Chinese medicinal herb Wikstroemia indica C.A. Mey. One active component, daphnoretin (7-hydroxyl-6-methoxy-3,7'-dicoumarylether), was identified, which showed strong suppressive effects on the expression of the hepatitis B surface antigen (HBsAg) in human hepatoma Hep3B cells. To examine the signaling pathway of daphnoretin on the Hep3B cells, we pretreated Hep3B cells with 12-O-tetradecanoylphorbol-13-O-acetate (200 nM) for 24 hr to down-regulate intracellular protein kinase C (PKC) levels and found that the PKC-down-regulated Hep3B cells did not respond at all to daphnoretin. Furthermore, daphnoretin induced translocation of PKC from the cytosol to the membrane and down-regulated intracellular PKC levels in the Hep3B cells, indicating that it may directly activate PKC. This hypothesis was supported by the observation that daphnoretin directly competed with [3H]phorbol dibutyrate for the binding of PKC in the whole cell and activated purified PKC activity in vitro. Our results demonstrated that daphnoretin, with a structure distinct from phorbol ester, is a PKC activator and has suppressive effects on HBsAg gene expression in human hepatoma cells.
Collapse
|