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41.
A new human cell line, WSU-BL, was established from a malignant ascitic fluid occurring in a patient with Burkitt's lymphoma. The established line grows in a single-cell suspension with a doubling time of 19 hours and expresses L3 morphologic features by the French-American-British classification. Immunologic study revealed that WSU-BL cells express IgM-lambda both in the cytoplasm and on the surface and react with monoclonal antibodies to B-cell antigens (B1, B4, BL3, BL4, HLA-DR, and common acute lymphoblastic leukemia antigen [CALLA]). These cells are negative for T-cell and myeloid/monocyte antigens as well as Epstein-Barr virus nuclear antigen (EBNA). These results suggest that WSU-BL corresponds to an intermediate stage of B-cell differentiation. Both fresh tumor and WSU-BL cells had a hyperdiploid karyotype carrying the 8;14 chromosome translocation. Molecular studies showed that WSU-BL has a rearrangement of c-myc proto-oncogene and expresses c-myc RNA. Phorbol ester 12-0-tetradecanoylphorbol-13-acetate (TPA) and interferon-gamma (IFN-gamma) were able to induce several phenotypic changes on WSU-BL cells. Two-dimensional gel electrophoresis of total cellular protein showed that either TPA or IFN-gamma induced both the synthesis or loss of several proteins. Analysis of the protein patterns indicated that some proteins were uniquely responsive to either TPA or IFN-gamma and others were common to both. This cell line should be valuable for future studies of cell proliferation, differentiation, and oncogenesis concerning this neoplasm. 相似文献
42.
Zenab Amin Ralitza Gueorguieva Angela Cappiello Kathryn A Czarkowski Stephanie Stiklus George M Anderson Frederick Naftolin C Neill Epperson 《Neuropsychopharmacology》2006,31(11):2489-2497
Despite an abundance of data in animals, there is little research in humans regarding how estrogen and serotonin (5-HT) may interact to influence cognition. Through the use of estrogen treatment (ET) and tryptophan depletion (TRP-D) in a within-subject design involving healthy menopausal women, we have manipulated both estrogen and 5-HT in order to evaluate their individual and joint effects. Although neither manipulation influenced visuospatial learning, a significant interaction suggested that estrogen exerted a protective effect on verbal memory, such that TRP-D impaired performance to a greater extent before the administration of ET. In consonance with this finding, ET was associated with a small, but positive mood effect on the day following active TRP-D. In addition, ET significantly improved letter-cued verbal fluency with and without TRP-D. Finally, time since last menstrual period was significantly associated with verbal memory scores, such that longer length of hypogonadism resulted in decreased verbal memory performance. These data support the interaction of estrogen and 5-HT in nonreproductive behavior in humans as well as highlight the role of ovarian steroids in cognition. 相似文献
43.
44.
Jamal M. Arif Sikandar G. Khan Mohammad Aslam Nayyara Mahmood Qamar Rahman 《Basic & clinical pharmacology & toxicology》1992,71(1):37-40
Abstract: In order to determine the pulmonary toxicity of kerosene and its ignition product (soot) in asbestos exposed subjects, the activities of phase I and phase II drug metabolizing enzymes in rat lungs after single intratracheal coexposure to Indian chrysotile asbestos and kerosene or its soot and Indian chrysotile were assayed. Exposure to kerosene or its soot resulted in a significant increase in the level of microsomal cytochrome P-450 and the activity of P-450 dependent monooxygenase, benzo(a)pyrene hydroxylase, as well as in the activities of microsomal epoxide hydrase and cytosolic glutathione-S-transferase (GST). However, in chrysotile exposed animals a reverse pattern in these parameters was recorded. The co-exposure to chrysotile and kerosene or chrysotile and soot led to a significant depletion in cytochrome P-450 level and a decrease in the activities of benzo(a)pyrene hydroxylase, epoxide hydrase and GST when compared to kerosene and soot controls, respectively. These results suggest that asbestos by altering the pulmonary drug metabolizing enzyme system may increase the toxic potential of kerosene and its ignition product in the respiratory system. 相似文献
45.
William Davies Mohammad Jazayeri Patrick Tchou 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1988,2(3):283-286
Summary Encainide is a type Ic antiarrhythmie agent. During encainide therapy, mild Q-T interval prolongation can be seen, usually associated with prolongation of the Q-R-S interval. The present case report describes an unusual and marked prolongation of the Q-T interval with no Q-R-S interval prolongation in a patient who was treated with encainide for atrioventricular nodal reentrant tachycardia. The drug metabolite profile in this patient's serum indicated an unusual elevation of the 3-methoxy-O-demethyl encainide metabolite, versus O-demethyl encainide. This elevated metabolite level suggests that 3-methoxy-O-demethyl encainide has a significant effect on prolongation of repolarization. An abnormal metabolism of encainide may be the underlying mechanism by which some patients would manifest an unusual prolongation of Q-T interval during encainide therapy. 相似文献
46.
47.
Effects of alkyl chain length on the inhibition of NNK-induced lung neoplasia in A/J mice by arylalkyl isothiocyanates 总被引:4,自引:1,他引:3
Morse Mark A.; Eklind Karin I.; Amin Shantu G.; Hecht Stephen S.; Chung Fung-Lung 《Carcinogenesis》1989,10(9):1757-1759
Six homologous arylalkyl isothiocyanates were evaluated fortheir abilities to inhibit pulmonary adenomas induced by thetobacco-specific nitrosamine 4-(methylnitrosamino)-l-(3-pyridyl)-1-butanone(NNK) in A/J mice. Four consecutive daily doses (5 µmol/mouse)of phenyl isothiocyanate (PITC), benzyl isothiocyanate (BITC),phenethyl isothiocyanate (PETTC), 3-phenylpropyl isothiocyanate(PPITC), 4-phenylbutyl isothiocyanate (PBITC), 4-oxo-4-(3-pyridyl)-butylisothiocyanate (OPBITC) and corn ofl were administered to miceby gavage. Two hours following the final dosing, mice were administeredsaline or 10 µmol of NNK in saline i.p. Pulmonary adenomaswere counted at 16 weeks after NNK administration. The miceadministered only corn oil prior to NNK developed an averagemultiplicity of 9.2 tumors/ mouse. Pretreatment with PITC, BITCand OPBITC had no significant effects on NNK-induced lung neoplasia.However, PEITC pretreatment resulted in a 64% reduction of lungtumor multiplicity, but did not affect the percentage of micethat developed tumors. Both PPITC and PBITC decreased tumormultiplicity by 96% and the percentage of tumor-bearing animalsby >60%. These results, in conjunction with our previouswork, demonstrate a general trend of increasing inhibition ofNNK-induced lung neoplasia by arylalkyl isothiocyanates withincreasing alkyl chain length. This study also demonstratesthe remarkable inhibitory activities of PPITC and PBITC, twoisothiocyanates that had not previously been tested as chemopreventiveagents. 相似文献
48.
A case of nontraumatic rupture of the ureter secondary to a nonopaque calculus is presented. Because of the inherent high image contrast caused by the leak of technetium 99m-DTPA-labeled urine, the technetium 99m DTPA excretory urogram is seen as an alternative to the intravenous urogram or contrast-enhanced computed tomography in selected cases of suspected ureteral rupture. 相似文献
49.
A horizontal double skin island pectoralis major myocutaneous flap with preservation of nipple-areola complex is described, a different modification used to reconstruct a complex defect following radical resection of a locally advanced gingival carcinoma. The skin islands are horizontally separated by a distance of 2.5 cm but rely on one vascular pedicle for their blood supply. The muscle between the skin islands provides the soft tissue bulk between the internal mucosal and external skin lining. The need for a separate segmental flap or a split-thickness skin graft for mucosal lining was eliminated. 相似文献
50.