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51.
Ida-Marie Stender Takafumi Etoh Tetsuya Tsuchida Hidemi Nakagawa H. Randolph Byers Genji Imokawa Yasumasa Ishibashi 《The Journal of dermatology》1993,20(10):611-617
The ability of the human amelanotic melanoma cell line MM-RU to produce experimental metastases and to grow tumors at subcutaneous inoculation sites in 4-week-old nude mice was examined. After i.v. inoculation of 106 cells, all injected mice (n=21) developed consistent numbers of metastatic pulmonary colonies within 32 days. The coefficients of variation for the number of colonies were between 17%–23% in three independent experiments. Survival time after i.v. inoculation was 63 ± 7 days (mean ± SD) (n=20). Within 20 days, subcutaneous inoculation of 5 × 106 cells resulted in tumor growths of 13 ± 3 mm (mean ± SD) at the inoculation sites in all nude mice (n=12). The MM-RU cell line seems to be a simple, fast vehicle for testing the effect of melanoma growth modulators on experimental pulmonary metastases as well as on subcutaneously growing melanoma. 相似文献
52.
Development of new immunoradiometric assay for CA 125 antigen using two monoclonal antibodies produced by immunizing lung cancer cells 总被引:4,自引:0,他引:4
Mihoko Kunimatsu Keigo Endo Tetsuo Nakashima Toshikazu Awaji Tsuneo Saga Yuji Watanabe Yasutaka Kawamura Hitoya Ohta Mitsuru Koizumi Harumi Sakahara Junji Konishi Shingo Fujii Takahide Mori Kanji Torizuka Yoichiro Matsuoka Tsuyoshi Nakagawa Nobuo Yamaguchi 《Annals of nuclear medicine》1988,2(2):73-79
CA 125 is an antigen associated with non-mucinous epithelial ovarian cancer, which is defined by OC 125 antibody developed by immunizing ovarian cancer cells. We have produced two monoclonal antibodies, 130-22 and 145-9, by using the human lung adenocarcinoma cell line PC-9. Both 130-22 and 145-9 antibodies recognized CA 125 antigen. However, the binding sites seemed to be separate from those of OC 125. Testing by 9 immunoradiometric assays (IRMA), using different combinations of the 3 monoclonal antibodies 130-22, 145-9 and OC 125 demonstrated that the best standard curve for detecting CA 125 could be obtained by a "simultaneous sandwich" assay based on a mixture of 125I-labeled OC 125 and 130-22 or 145-9 coated beads. One-step IRMA, using 130-22 as a tracer and 145-9 as an immunoadsorbent, also showed good reproducibility and sensitivity for measuring CA 125. Antigens were detectable in the culture supernatants of PC-9 cells and 5 of 6 ovarian cancer and endometrial adenocarcinoma cells. These results indicate that one-step IRMA using 130-22 and 145-9 is useful for detecting CA 125 antigen. 相似文献
53.
A single oral administration of orthophenylphenol (OPP, 1400 mg/kg; about half the LD50) to male Fischer 344 rats produced an elevation of serum transaminase activity 24 h later. Pretreatment with l-buthionine-S,R-sulfoximine (BSO, 900 mg/kg) in the OPP-treated rats potentiated the hepatic and renal damage which was accompanied by necrosis. Six hours after the administration of OPP (700 or 1400 mg/kg), hepatic and renal glutathione (GSH) levels decreased with increasing dosage. Hepatic GSH depletion with OPP was enhanced with BSO pretreatment and the recovery of GSH in both organs was slow in the high-dose OPP group. These results suggest that hepatic and renal damage is associated with a serious and prolonged GSH depletion. When either phenyl-p-benzoquinone (PBQ) or phenylhydroquinone (PHQ), which are intermediates of OPP, was administered orally to rats at 700 or 1400 mg/kg, the mortality with the high dose of PBQ was 75% at 24 h. The serum transaminase activity and UN level increased with the low dose of PBQ, accompanied by necrotic hepatocytes. The toxic effects of PHQ on kidney or liver were less than those on PBQ. These observations suggest that the liver and kidney may be target organs for toxic actions of a large dose of OPP and its intermediate, PBQ.Part of this work was presented at IInd International ISSX Meeting Xenobiotic Metabolism and Disposition, May 16–20, 1988, Kobe, Japan 相似文献
54.
Summary In the present investigation, administration of a single i.p. dose of the anticancer drug merbarone [5-(N-phenylcarboxamido)-2-thiobarbituric acid] produced an acute and reversible decrease in renal function in female but not male Fischer 344 rats. The renal lesion in female rats was biochemically characterized as a decrease inp-aminohippuric acid accumulation by renal slices along with polyuria, glucosuria, proteinuria, and enzymuria. These functional changes were accompanied by histopathologic changes of focal tubular necrosis that was confined to the deep cortex and outer stripe of the outer medulla. The changes in these parameters were dose-dependent and were observed at doses as low as 0.2×MELD10 (12 mg/kg). This low merbarone dose increased urinary glucose and protein excretion by 26- and 9-fold, respectively, in the initial 16-h urine collection in female rats. This increase was accompanied by a 2- to 15-fold increase in the excretion ofN-acetyl--d-glucosaminidase (NAG), -glutamyl transpeptidase (-GTP), and lactate dehydrogenase (LDH) activities. No significant changes in renal function were observed in male rats apart from mild enzymuria after a high dose of merbarone (36 mg/kg). The drug did not increase urea nitrogen levels in male or female rats, reflecting the focal nature of this tubular lesion. Merbarone produced small elevations in serum transaminase activities [i. e., glutamic-oxalacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT)] at doses that produced marked alterations in renal function in female rats, suggesting only mild hepatotoxicity. The present study establishes the kidney as a possible dose-limiting target organ for merbarone toxicity. 相似文献
55.
Huang Y Komatsu T Nakagawa A Tsuchida E Kobayashi S 《Journal of biomedical materials research. Part A》2003,66(2):292-297
Recombinant human serum albumin including 2-[8-[N-(2-methylimidazolyl)]octanoyloxymethyl]-5,10,15,20-tetrakis(alpha,alpha,alpha,alpha-o-pivaloylamino)phenylporphinatoiron(II) (albumin-heme; rHSA-FeP) is a synthetic hemoprotein that has sufficient capability to reversibly bind and release O(2) under physiological conditions (pH 7.3, 37 degrees C) similar to hemoglobin and myoglobin. In order to use this albumin-based O(2) carrier as a new class of red blood cell substitutes, its compatibility with blood cell components carefully was investigated in vitro. After the addition of the rHSA-FeP solution into whole blood at 10, 20, and 44 vol %, the FeP concentration in the plasma phase remained constant for 6 h at 37 degrees C in each group, and no significant time dependence was observed in the numbers of red blood cells, white blood cells, or platelets. The microscopic observations clearly showed that the shapes of the red blood cells had not been deformed during the measurement period. With respect to the blood coagulation parameters (prothrombin time and activated partial thromboplastin time), the coexistence of rHSA-FeP had only a negligibly small influence. Also the blood compatibility under dynamic flow conditions was evaluated using a microchannel array flow analyzer. All these results suggest that the albumin-heme has no effect on the morphology of blood cell components in vitro. 相似文献
56.
Okada N Takagi Y Tanaka M Tagawa M 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2003,273(1):663-668
The body of a Japanese flounder (Paralichthys olivaceus) changes from a symmetrical to an asymmetrical form during metamorphosis. To obtain detailed information on the mechanisms of the migration of the right eye to the left side, soft and hard tissues in the head of larval flounders were examined using transmission electron microscopy (TEM). Retrorbital vesicles (Rvs) are pairs of sac-like structures under the eyes. It has been suggested that the asymmetrical development of Rvs, with the right (blind) one being bigger than the left, is the driving force behind eye migration. The present study revealed that the ultrastructure of the Rv sheath is quite similar to that of a lymphatic capillary. Thus, it is possible that the Rv is a part of the lymph system, and is probably related to the secondary vascular system in teleosts. If we assume that the Rv sheath has a high permeability to liquid, similar to lymphatic capillaries, it is not plausible that the active expansion of the Rv pushes the eyeball. On the other hand, the pseudomesial bar (Pb) is a bone that is unique to flounders and is present only on the right (blind) side. At the beginning of eye migration, an aggregation of fibroblast-like cells is observed in the dermis under the right eye, where the Pb will subsequently be formed. These cells have a well-developed rough endoplasmic reticulum (rER) and mitochondria, and are probably responsible for formation of the thick layers of collagen fibrils around them. Since it is unlikely that the active expansion of the Rv causes eye migration, the role played by the Pb and its rudiment becomes more significant in right eye migration in the Japanese flounder becomes more significant. 相似文献
57.
Comparison of antinuclear antibody testing methods: immunofluorescence assay versus enzyme immunoassay. 下载免费PDF全文
R A Gniewek D P Stites T M McHugh J F Hilton M Nakagawa 《Clinical and Vaccine Immunology : CVI》1997,4(2):185-188
Performances of anti-nuclear antibody testing by immunofluorescence assay (ANA-IFA) and enzyme immunoassay (ANA-EIA) were compared in relation to patient diagnosis. A total of 467 patient serum samples were tested by ANA-IFA (Kallestad; Sanofi) and ANA-EIA (RADIAS; Bio-Rad), and their age, sex, diagnosis, disease status, and medications were obtained through chart review. Reference ranges were established by testing 98 healthy blood donor samples. Eighty-six samples came from patients with diffuse connective tissue diseases, including systemic lupus erythematosus, discoid lupus erythematosus, or drug-induced lupus (n = 71); systemic sclerosis, CREST syndrome (calcinosis, Raynaud's phenomenon, esophageal motility abnormalities, sclerodactyly, and telangiectasia), or Raynaud's syndrome (n = 8); Sjögren's syndrome (n = 5); mixed connective tissue disease (n = 5); and polymyositis or dermatomyositis (n = 3). The sensitivity, specificity, positive predictive value, and negative predictive value for ANA-IFA were 87.2, 48.0, 29.1, and 93.9%, respectively, for the reference range of < 1:160. For ANA-EIA, they were 90.7, 60.2, 35.8, and 96.4%, respectively, for the reference range of < 0.9. ANA-EIA offers equivalent sensitivity and higher specificity compared to ANA-IFA. 相似文献
58.
Keiichi Ueda Shigemitsu Nakagawa Ken-ichi Kawahara Tomozo Fujita 《Medical molecular morphology》1993,26(3-4):191-194
Extirpated specimens of a squamous cell carcinoma from a human thigh were transplanted to the subcutaneous tissue of nude mice. Fourteen days later, the transplanted tumor masses were, again, extirpated from the nude mice. The transplanted chimera of the squamous cell carcinoma as seen with the electron microscope resembled the tumor cells before transplantation. It is concluded that ultrastructural investigation of transplanted chimera from squamous cell carcinoma cases may be useful for examining the site of action and clinical effects of anticancer drugs on this kind of tumor. 相似文献
59.
Specific Inhibitory Action of Anisodamine against a Staphylococcal Superantigenic Toxin, Toxic Shock Syndrome Toxin 1 (TSST-1), Leading to Down-Regulation of Cytokine Production and Blocking of TSST-1 Toxicity in Mice 下载免费PDF全文
60.
Maeno-Hikichi Y Chang S Matsumura K Lai M Lin H Nakagawa N Kuroda S Zhang JF 《Nature neuroscience》2003,6(5):468-475
Multiple protein kinase C (PKC) isozymes are present in neurons, where they regulate a variety of cellular functions. Due to the lack of specific PKC isozyme inhibitors, it remains unknown how PKC acts on its selective target(s) and achieves its specific actions. Here we show that a PKC binding protein, enigma homolog (ENH), interacts specifically with both PKCepsilon and N-type Ca2+ channels, forming a PKCepsilon-ENH-Ca2+ channel macromolecular complex. Coexpression of ENH facilitated modulation of N-type Ca2+ channel activity by PKC. Disruption of the complex reduced the potentiation of the channel activity by PKC in neurons. Thus, ENH, by interacting specifically with both PKCepsilon and the N-type Ca2+ channel, targets a specific PKC to its substrate to form a functional signaling complex, which is the molecular mechanism for the specificity and efficiency of PKC signaling. 相似文献