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1.
Cytologic examination of sputum samples from an elderly patient revealed the presence of two cell populations: squamous cell carcinoma cells and rhabdomyosarcoma cells. The abnormal squamous cells showed both keratinizing and nonkeratinizing forms while some of the rhabdomyosarcoma cells showed cross striations. Sputum cytology was thus able to suggest a diagnosis of pulmonary carcinosarcoma. Histologically, the tumor was composed mainly of sarcomatous tissue showing various kinds of cells: fusiform or fibrous cells, round anaplastic cells, spindled cells with typical cross striations and myoblastic cells. A partially myxomatous degeneration was present. In addition, squamous cell carcinoma proliferated along the bronchi and formed small invasive cell nests in the sarcomatous tissue. No transition between the two components was noted. Both cellular constituents had metastasized to an interlobar lymph node.  相似文献   
2.
A chemical method for the determination of dermatan sulfate (DS) and oversulfated dermatan sulfate has been developed and applied to the pharmacokinetic study of these polysaccharides in experimental animals. The analytical procedure includes a simple preparation step of administered DS and oversulfated DS from blood plasma, HPLC for the separation and detection of DS and oversulfated DS using an Asahipak NH2P-50 column, fluorometric reaction of the polysaccharides with guanidine in a strong alkaline medium. DS and oversulfated DS were extracted from plasma by treating it with proteinase to remove plasma proteins and recovered with endogenous plasma glycosaminoglycans by ethanol precipitation. Finally, DS and oversulfated DS were analyzed by fluorometric HPLC. The detection limits of DS and oversulfated DS were 10 and 20 ng, respectively. Furthermore, we demonstrated that artificial oversulfation of DS increased its biological half-life after intravenous administration to rats.  相似文献   
3.
Molecular Biology Reports - The emu (Dromaius novaehollandiae) is a useful poultry animal farmed for fat, meat, and eggs. Genetic structure and relationships among farmed emu populations in Japan...  相似文献   
4.
Lipid alkyl radicals generated from polyunsaturated fatty acids via chemical or enzymatic H-abstraction have been a pathologically important target to quantify. In the present study, we established a novel method for the quantification of lipid alkyl radicals via nitroxyl radical spin-trapping. These labile lipid alkyl radicals were converted into nitroxyl radical-lipid alkyl radical adducts using 3-carbamoyl-2,2,5,5-tetramethyl-3-pyrroline-N-oxyl (CmdeltaP) (a partition coefficient between octanol and water is approximately 3) as a spin-trapping agent. The resulting CmdeltaP-lipid alkyl radical adducts were determined by HPLC with postcolumn online thermal decomposition, in which the adducts were degraded into nitroxyl radicals by heating at 100 degrees C for 2 min. The resulting nitroxyl radicals were selectively and sensitively detected by electrochemical detection. With the present method, we, for the first time, determined the lipid alkyl radicals generated from linoleic acid, linolenic acid, and arachidonic acid via soybean lipoxygenase-1 or the radical initiator 2,2'-azobis(2,4-dimethyl-valeronitrile).  相似文献   
5.
The function of CD44-v3 and heparin/heparan sulfate (HS) signaling was investigated during trophoblast cell migration to identify their role in the renewal of syncytial layer damage caused by increased hemodynamic turbulence in the intervillous space and maintenance of syncytial integrity in pre-eclampsia. We evaluated the effect of heparin/HS/CD44-v3-mediated processes during scratch wound closure in monolayer immortalized human trophoblast cells derived from term placenta (TCL-1 cells). Western blot analysis showed that these cultured human trophoblast cells express the epidermal growth factor receptor and CD44-v3 but do not express syndecan 4. An in vitro scratch wound healing assay showed enhanced migration of trophoblast cells in a dose-dependent manner in the presence of heparin compared with controls when cultured under serum-free conditions. Conversely, an anti-CD44 function-blocking antibody and CD44 siRNA suppressed the migration of trophoblast cells in the presence of heparin in a similar scratch assay. Furthermore, both heparin treatment and in vitro scratch wounding induced the phosphorylation of p21-activated kinase 1 (PAK1), whereas the anti-CD44-v3 antibody suppressed the heparin-induced phosphorylation of PAK1 in trophoblast cells. These results indicate that heparin/HS/CD44-v3-mediated signaling, in the absence of growth factor networks, enhances the direct repair of the damaged trophoblast layer through the migration of trophoblast cells. This renewed cell coverage may lead to the maintenance of syncytiotrophoblast cell function and an associated reduction in pathogenic soluble factors derived from the damaged trophoblast cells.  相似文献   
6.
Lipoxygenases have been proposed to be a possible factor that is responsible for the pathology of certain diseases, including ischaemic injury. In the peroxidation process of linoleic acid by lipoxygenase, the E,Z-linoleate allyl radical-lipoxygenase complex seems to be generated as an intermediate. In the present study, we evaluated whether E,Z-linoleate allyl radicals on the enzyme are scavenged by radical scavengers. Linoleic acid, the content of which was greater than the dissolved oxygen content, was treated with soya bean lipoxygenase-1 (ferric form) in the presence of radical scavenger, CmP (3-carbamoyl-2,2,5,5-tetramethylpyrrolidine-N-oxyl). The reaction rate between oxygen and lipid allyl radical is comparatively faster than that between CmP and lipid allyl radical. Therefore a reaction between linoleate allyl radical and CmP was not observed while the dioxygenation of linoleic acid was ongoing. After the dissolved oxygen was depleted, CmP stoichiometrically trapped linoleate-allyl radicals. Accompanied by this one-electron redox reaction, the resulting ferrous lipoxygenase was re-oxidized to the ferric form by hydroperoxylinoleate. Through the adduct assay via LC (liquid chromatography)-MS/MS (tandem MS), four E,Z-linoleate allyl radical-CmP adducts corresponding to regio- and diastereo-isomers were detected in the linoleate/lipoxygenase system, whereas E,E-linoleate allyl radical-CmP adducts were not detected at all. If E,Z-linoleate allyl radical is liberated from the enzyme, the E/Z-isomer has to reach equilibrium with the thermodynamically favoured E/E-isomer. These data suggested that the E,Z-linoleate allyl radicals were not liberated from the active site of lipoxygenase before being trapped by CmP. Consequently, we concluded that the lipid allyl radicals complexed with lipoxygenase could be scavenged by radical scavengers at lower oxygen content.  相似文献   
7.
The quantitative alterations of hyaluronan and dermatan sulfate in the upper dermis (fibrous tissue) and the lower dermis (adipose tissue) of the hairless mouse skin chronically exposed to the UV irradiation as solar-simulating irradiation (lambda(max) 352 nm, UV distribution: 300-310 nm, 0.9%; 310-320 nm, 2.0%; 320-420 nm, 97.1%) were evaluated. Hyaluronan and dermatan sulfate contents in each part of dermis were determined as follows: skin sections on a glass slide prepared by histological technique were processed into the upper dermis and the lower dermis with a small surgical knife, and treated with chondroitinase ABC and ACII in the presence of bacterial collagenase. The resulting unsaturated disaccharides were determined by HPLC method. By applying this method to the UV-irradiated hairless mouse skin, it was found that the chronic UV irradiation increased dermatan sulfate in the upper dermis, whereas an increase of hyaluronan content was not statistically significant. In the lower dermis, on the contrary, both hyaluronan and dermatan sulfate contents remarkably increased as compared with the control mice. Furthermore, the histological study showed the accumulation of the collagen fibers in the lower dermis of the UV-irradiated hairless mouse skin following the disappearance of adipocytes. These findings indicate that the increases of glycosaminoglycan contents in the UV-irradiated skin are related to the accumulation of the extracellular matrix components in the lower dermis.  相似文献   
8.
Reactive oxygen species (ROS) may play key roles in vascular inflammation and atherogenesis in patients with diabetes. In this study, xanthine oxidase (XO) system was examined as a potential source of superoxide in mice with streptozotocin (STZ)-induced experimental diabetes. Plasma XO activity increased 3-fold in diabetic mice (50±33?μU/ml) 2 weeks after the onset of diabetes, as compared with non-diabetic control mice (15±6?μU/ml). In vivo superoxide generation in diabetic mice was evaluated by an in vivo electron spin resonance (ESR)/spin probe method. Superoxide generation was significantly enhanced in diabetic mice, and the enhancement was restored by the administration of superoxide dismutase (SOD) and 4,5-dihydroxy-1,3-benzene disulfonic acid (Tiron), which was reported to scavenge superoxide. Pretreatment of diabetic mice with XO inhibitors, allopurinol and its active metabolite oxipurinol, normalized the increased superoxide generation. In addition, there was a correlation (r=0.78) between the level of plasma XO activity and the relative degree of superoxide generation in diabetic and non-diabetic mice. Hence, the results of this study strongly suggest that superoxide should be generated through the increased XO seen in the diabetic model mice, which may be involved in the pathogenesis of diabetic vascular complications.  相似文献   
9.
Inducible nitric oxide synthase (iNOS) is one of the clinical targets in rheumatoid arthritis. Synoviocytes, macrophages, and chondrocytes in the joints of patients with rheumatoid arthritis appear to express iNOS, but the contribution of iNOS molecules to rheumatoid arthritis is not yet clear. This study used adjuvant-induced arthritis in rats as a model to examine the association between the iNOS expression and its activity in rheumatoid arthritis. In adjuvant-injected rats, arthritic changes in the paw were first observed between days 10 and 12. NO-generation activity was precisely determined by combining an electron spin resonance/nitric oxide (NO)-trapping method with the method of standard addition using an NO generator, and we found that the activity in the joint samples was extremely high on day 10. The administration of S-(2-aminoethyl)isothiourea, a selective iNOS inhibitor, from day 0 to day 10, effectively reduced the paw swelling. Immunohistological studies showed that chondrocytes expressed iNOS on days 7-14 and that nitrotyrosine residues, a footprint of NO generation, were produced on day 10. This indicates that NO generation by iNOS induced in chondrocytes is a key event in the induction of adjuvant arthritis.  相似文献   
10.
14 C] adenine to young leaves of tea (Camellia sinensis L.). Light did not have any significant influence on the levels of radioactivity associated with the purine alkaloids. The long-term effects of light on caffeine production were studied using young shoots from plants that were maintained in almost complete darkness (1% full sunlight) by being covered with black lawn cloth. In the control shoots of the naturally-grown plants there were net increases in the total purine alkaloid contents of 2,430 nmoles shoot−1, while in shoots that had been in darkness for 7 days much lower increases, 564 nmoles shoot−1, were observed. Caffeine synthase (CS) activity was 332±55 pkat shoot−1 in light which is ca. 40% higher than the 237±37 pkat shoot−1 in plants kept darkness for 7-days. However, a similar pattern of the metabolism of [8-14C] adenine was observed in naturally-grown and dark-grown shoots. These findings indicate light is not essential for the biosynthesis of caffeine in young tea shoots. The lower net formation of caffeine in shoots maintained in darkness is an indirect consequence of the reduced growth rate of the young shoots in the absence of light. Received 17 January 2000/ Accepted in revised form 13 March 2000  相似文献   
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