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1.
For 13 years polyarthritis with specific synovial involvement was observed in a case of type II hyperlipoproteinemia. Microcrystals similar to those described in Gaucher's and Fabry's disease were seen in synovial cytoplasm and mitochondria. These data suggest a microcrystalline pathogenesis for type II hyperlipoproteinemia arthritis as in gout and chondrocalcinosis.  相似文献   

2.
Articular manifestations may be the onset of genetic alpha galactosidase deficiency (Fabry's disease). Ultrastructural study shows typical osmiophilic lamellar inclusions of trihexosylceramides in synoviocytes, capillaries and adipocytes. Furthermore microcrystals identical to those seen in Gaucher's disease and type II hyperlipoproteinemia were observed in mitochondria and free in cytoplasm. These data suggest a microcrystalline pathogenesis of these arthropathies, as in gout and chondrocalcinosis, and what we have generally called crystallopathic arthropathies.  相似文献   

3.
Absorption of metal ions by KB, HeLa and L-59 cells has been analyzed by atomic absorption spectrophotometry in the course of culture. Ions of the elements of the fourth period in the periodic chart such as Fe(II), Cu(II), Zn(II), Mn(II) and Ni(II) were not taken up, but those of the higher periods, such as Cd(II), Pb(II), Hg(II) and Ag(I) were were taken up easily. The uptake behavior by the cultured cells was in accordance with the characteristic features of metals, that metals in the fourth period are essential elements, and most of the elements of the fifth and the sixth periods are non-essential or toxic elements. The initial rate of Cd(II) uptake and the Cd(II) concentration has a sigmoidal relationship. Cd(II) was absorbed homotropically through cell membranes. The uptake of Cd(II) was specifically inhibited by Cu(II), but was affected little by Zn(II). The toxicity of Cd(II) to KB cells was greatly enhanced in the presence of Cu(II). On the contrary, the toxicity of Cd(II) was reduced by the addition of Zn(II) at several concentrations of Cd(II). The toxicity of Cd(II) did not depend on the amount of Cd(II) absorbed in the cells, but was determined by cofactors such as Cu(II). The interaction between Cd(II) and Cu(II) may be important for Itai-itai disease.  相似文献   

4.
The fibrin(ogen) receptor, integrin α(IIb)β(3), has a well-established role in platelet spreading, aggregation and clot retraction. How α(IIb)β(3) contributes to platelet-dependent coagulation is less well resolved. Here, we demonstrate that the potent suppressing effect of clinically used α(IIb)β(3) blockers on tissue factor-induced thrombin generation is linked to diminished platelet Ca(2+) responses and phosphatidylserine (PS) exposure. The same blockers suppress these responses in platelets stimulated with collagen and thrombin receptor agonists, whereas added fibrinogen potentiates these responses. In platelets spreading on fibrinogen, outside-in α(IIb)β(3) signaling similarly enhances thrombin-induced Ca(2+) rises and PS exposure. These responses are reduced in α(IIb)β(3)-deficient platelets from patients with Glanzmann's thrombasthenia. Furthermore, the contribution of α(IIb)β(3) to tissue factor-induced platelet Ca(2+) rises, PS exposure and thrombin generation in plasma are fully dependent on Syk kinase activity. Tyrosine phosphorylation analysis confirms a key role of Syk activation, which is largely but not exclusively dependent on α(IIb)β(3) activation. It is concluded that the majority of tissue factor-induced procoagulant activity of platelets relies on Syk activation and ensuing Ca(2+) signal generation, and furthermore that a considerable part of Syk activation relies on α(IIb)β(3) signaling. These results hence point to a novel role of Syk in integrin-dependent thrombin generation.  相似文献   

5.
Summary Absorption of metal ions by KB, HeLa and L-59 cells has been analyzed by atomic absorption spectrophotometry in the course of culture. Ions of the elements of the fourth period in the periodic chart such as Fe(II), Cu(II), Zn(II), Mn(II) and Ni(II) were not taken up, but those of the higher periods, such as Cd(II), Pb(II), Hg(II) and Ag(I) were were taken up easily. The uptake behavior by the cultured cells was in accordance with the characteristic features of metals, that metals in the fourth period are essential elements, and most of the elements of the fifth and the sixth periods are non-essential or toxic elements.The initial rate of Cd(II) uptake and the Cd(II) concentration has a sigmoidal relationship. Cd(II) was absorbed homotropically through cell membranes. The uptake of Cd(II) was specifically inhibited by Cu(II), but was affected little by Zn(II). The toxicity of Cd(II) to KB cells was greatly enhanced in the presence of Cu(II). On the contrary, the toxicity of Cd(II) was reduced by the addition of Zn(II) at several concentrations of Cd(II). The toxicity of Cd(II) did not depend on the amount of Cd(II) absorbed in the cells, but was determined by cofactors such as Cu(II). The interaction between Cd(II) and Cu(II) may be important for Itai-itai disease.  相似文献   

6.
用原位聚合法制备了Sr0.7La0.15Ce0.15Fe11.7Zn0.3O19铁氧体/聚苯胺(PAn)复合材料。采用X射线衍射(XRD)、扫描电子显微镜(SEM)对样品的结构、微观表面形貌和粒子大小进行了表征,用微波矢量网络分析仪测量样品在2~12.4GHZ频率范围内复介电常数和复磁导率,根据测量数据计算微波反射率R与频率f的关系。研究结果表明:PAn包覆于掺杂锶铁氧体表面,PAn/Sr0.7La0.15Ce0.15Fe11.7Zn0.3O19复合材料具有良好的吸波性能,随着掺杂锶铁氧体含量的增加,微波吸收匹配厚度和吸收带宽发生变化:当Sr0.7La0.15Ce0.15Fe11.7Zn0.3O19聚合质量比为40%时,最佳匹配厚度为2.6mm,吸收峰值接近-40dB,峰值频率高于12.4GHz,大于10dB吸收带宽预计达到55GHz。  相似文献   

7.
8.
When recombinant and cellular prion protein (PrP(C)) binds copper, it acquires properties resembling the scrapie isoform (PrP(Sc)), namely protease resistance, detergent insolubility and increased beta sheet content. However, whether the conformations of PrP(C) induced by copper and PrP(Sc) are similar has not been studied in great detail. Here, we use a panel of seven monoclonal antibodies to decipher the epitopes on full-length mouse PrP(C) that are affected by exogenous copper, and to compare the antigenicity of the copper-treated full-length PrP(C) with the full-length PrP(Sc) present in scrapie-infected mouse brains. In the presence of copper, we found that epitopes along residues 115-130 and 153-165 become more accessible on PrP(C). These regions correspond to the two beta sheet strands in recombinant PrP and they were proposed to be important for prion conversion. However, when we compared the antibody-binding patterns between full-length PrP(C) with full-length PrP(Sc) and between copper-treated full-length PrP(C) with full-length PrP(Sc), antibody binding to residues 143-155 and 175-185 was consistently increased on PrP(Sc). Collectively, our results suggest that copper-treated full-length PrP(C) does not resemble full-length PrP(Sc), despite acquiring PrP(Sc)-like properties. In addition, since each full-length protein reacts distinctively to some of the antibodies, this binding pattern could discriminate between PrP(C) and PrP(Sc).  相似文献   

9.
The mechanisms of iron-mediated inhibition of the H(+)-ATPase activity of plasma membrane (PM) vesicles isolated from wheat roots were investigated. Both FeSO(4) and FeCl(3) significantly inhibited PM H(+)-ATPase activity, and the inhibition could be reversed by the addition of the metal ion chelator EDTA-Na(2) or a specific Fe(2+) chelator, indicating that the inhibitory effect was due to specific action of Fe(2+) or Fe(3+). Measurement of the extent of lipid peroxidation showed that oxidative damage on the PM caused by Fe(2+) or Fe(3+) seemed to be correlated with the inhibition of PM H(+)-ATPase activity. However, prevention of lipid peroxidation with butylated hydroxytoluene did not affect iron-mediated inhibition in the PM H(+)-ATPase, suggesting that the inhibition of the PM H(+)-ATPase was not a consequence of lipid peroxidation caused by iron. Investigation of the effects of various reactive oxygen species scavengers on the iron-mediated inhibition of H(+)-ATPase activity indicated that hydroxyl radicals (*OH) and hydrogen peroxide (H(2)O(2)) might be involved in the Fe(2+)-mediated decrease in PM H(+)-ATPase activity. Moreover, iron caused a decrease in plasma protein thiol (P-SH), and Fe(3+) brought a higher degree of oxidation in thiol groups than Fe(2+) at the same concentration. Modification of the thiol redox state in the PM suggested that reducing thiol groups were essential to maintain PM H(+)-ATPase activity. Incubation of the specific thiol modification reagent 5,5-dithio-bis(2-nitrobenzoic acid) with the rightside-out and inside-out PM revealed that thiol oxidation occurred at the apoplast side of the PM. Western blotting analysis revealed a decrease in H(+)-ATPase content caused by iron. Taken together, these results suggested that thiol oxidation might account for the inhibition of PM H(+)-ATPase caused by iron, and that *OH and H(2)O(2) were also involved in Fe(2+)-mediated inhibition.  相似文献   

10.
Trypsin-treatment of human fat cells results in the potentiation of the lipolytic response and the cAMP accumulation induced by theophylline (5 . 10(-4) M) but not of those induced by theophylline (5 . 10(-3) M). The amount of cAMP formed after exposure to theophylline (5 . 10(-3) M) plus norepinephrine (5 . 10(-6) M) remains, however, 2.6 fold higher in trypsin-treated human fat cells than in the control ones.  相似文献   

11.
An international multilaboratory study was conducted to establish the optimal combination of culture media, incubation time and temperature for recovery of aeromonads from stools using blood ampicillin (10 mg/l) agar (BAA), starch ampicillin (10 mg/l) agar (SAA), and cefsulodin irgasan novobiocin agar (CIN) with alkaline peptone water (APW) for enrichment. Optimal recovery of aeromonads (167/186) occurred using BAA (37 degrees C; 24 h) and CIN (25 degrees C; 48 h) with APW (25 degrees C; 24 h) subcultured to BAA (37 degrees C; 24 h) and CIN (25 degrees C; 48 h).  相似文献   

12.
目的 定性、定量分析金银藤挥发油成分.方法 采用气相色谱-质谱进行检测,通过化学计量学解析法对二雏色谱/质谱数据进行解析,得到各组分的纯色谱曲线和质谱,从而实现对金银藤挥发油成分的定性、定量分析,并结合程序升温保留指数来鉴定化合物.结果 金银藤的挥发油鉴定了39个成分,定性组分含量占金银藤挥发油成分总含量的94.54%.结论 全银藤挥发油的主要成分为十六烷酸(45.86%)、9,12-十八碳二烯政乙酯(39.02%)、十四烷酸(1.8%)、十五烷酸(1.07%)、十八烷酸(1.02%).  相似文献   

13.
Summary The enzymatic hydrolysis of propionylcholine (PrCh), acetylthiocholine (AcThCh), and butyrylthiocholine (BuThCh), by extracts of the muscle rectus abdominis, was determined. Inhibition of this hydrolysis by D.F.P. and 3318 CT [bis(pipéridinométhylcoumaranyl- 5)cétone diméthiodide] — utilized over a range of concentrations covering both specific and non-specific concentrations—showed that PrCh is hydrolyzed by an acetylcholinesterase (70%) and an Xcholinesterase (30%), AcThCh by the AcChE (70%), the XChE (15%) and a thioesterase (15%) and BuThCh by the XChE (70%) and a thioesterase (30%).  相似文献   

14.
In cultures with efficient aeration a maximum cell concentration (MCC) of 6 X 10(5) cells/ml (defined medium) and 5.5 X 10(6) cells/ml (broth) can be reached. By culturing within Millicells with excess supply of medium and efficient removal of waste products a physical limit for MCC of about 13 X 10(6) cells/ml is reached.  相似文献   

15.
The construction of molecular models for the human serotransferrin glycans shows that they present one compact section linked to the protein and constituted by the pentasaccharide alpha-Man-(1 leads to 3)-[alpha-Man-(1 leads to 6)]-beta-Man-(1 leads to 4)-beta-GlcNAc-(1 leads to 4)-beta-GlcNAc-(1 leads to)-Asn to which are attached two "antennae" consisting of the trisaccharide alpha-NANA-(2 leads to 6)-beta-Gal-(1 leads to 4)-beta-GlcNAc. The trisaccharide sequence beta-Man-(1 leads to 4)-beta-GlcNAc-(1 leads to 4)-beta-GlcNAc adopts a flat and rigid conformation, stabilised by hydrogen bonds. In contrast, the sequence alpha-NANA-(1 leads to 6)-beta-Gal-(1 leads to 4)-beta-GlcNAc-(1 leads to 2)-alpha-Man takes up a helical configuration. The two "antennae" can be disposed on the pentasaccharide core to give two possible configurations, one Y-shaped and the other T-shaped. In both cases, the general conformation of the glycans is perfectly compatible with their postulated role as a recognition signal.  相似文献   

16.
Summary In rats, both Cu(I) and Cu(II) show an irritancy profile not shared with Cuo or Zn(II) or Ni(II). The gastric response to Cu(II), i.e. copius fluid and mucus secretion, can protect the stomach from the acute ulcerative effects of aspirin or physical stress administered subsequently.to whom all enquiries should be addressed, Supported by grants from the National Health and Medical Research Council (Austr.) and University of Tasmania Research Commitee.Acknowledgments: ProfessorsW. R. Walker (Newcastle, Austr.) andL. Field (Nashville, Tenn.) for gifts of Cu(I) and Zn complexes;Dr. J. R. J. Sorenson (Cincinnatti, Ohio) for illuminating discussion; Drs.D. D. Perrin (Canberra) andR. P. Agarwal (Washington D. C.) for providing stability constants and much helpful advice.  相似文献   

17.
Three forms of cyclic AMP phosphodiesterase from human platelets are resolved upon sucrose gradient centrifugation : 2.5S (monomer), 4.8S (dimer) and 7S (tetramer). They are interconvertible and form an association-dissociation equilibrium depending on the concentration of enzyme. The dissociated form has a high Km for cyclic AMP (Km : 3-5.10(-4) M) whereas the associated form has a low Km (Km : 3-5.10(-5) M).  相似文献   

18.
Kynurenine pathway (KP) is the primary path of tryptophan (Trp) catabolism in most mammalian cells. The KP generates several bioactive catabolites, such as kynurenine (Kyn), kynurenic acid (KA), 3-hydroxykynurenine (3-HK), xanthurenic acid (XA), and 3-hydroxyanthranilic acid (3-HAA). Increased catabolite concentrations in serum are associated with several cardiovascular diseases (CVD), including heart disease, atherosclerosis, and endothelial dysfunction, as well as their risk factors, including hypertension, diabetes, obesity, and aging. The first catabolic step in KP is primarily controlled by indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO). Following this first step, the KP has two major branches, one branch is mediated by kynurenine 3-monooxygenase (KMO) and kynureninase (KYNU) and is responsible for the formation of 3-HK, 3-HAA, and quinolinic acid (QA); and another branch is controlled by kynurenine amino-transferase (KAT), which generates KA. Uncontrolled Trp catabolism has been demonstrated in distinct CVD, thus, understanding the underlying mechanisms by which regulates KP enzyme expression and activity is paramount. This review highlights the recent advances on the effect of KP enzyme expression and activity in different tissues on the pathological mechanisms of specific CVD, KP is an inflammatory sensor and modulator in the cardiovascular system, and KP catabolites act as the potential biomarkers for CVD initiation and progression. Moreover, the biochemical features of critical KP enzymes and principles of enzyme inhibitor development are briefly summarized, as well as the therapeutic potential of KP enzyme inhibitors against CVD is briefly discussed.  相似文献   

19.
Summary Pheromonal secretions produced by females and males of the noctuid moth,Mocis megas (Guénée) have been analyzed by gas chromatography and mass spectrometry (EI (electron impact) and CI (chemical ionization)). The female sex pheromone was a blend of (Z,Z,Z) 3,6,9 heneicosatriene (55%) and (Z,Z) 3,6-cis-9S, 10R-epoxyheneicosadiene (45%). Male secretion produced at the level of a prothoracic organ was a blend of two unsaturated major hydrocarbons: (Z,Z) 6,9 heneicosadiene, (64%) and (Z,Z,Z) 3,6,9 heneicosatriene (24%) and C19, C20 and C22 homologues (total ratio 12%), as minor components. The trienic hydrocarbon was present in both sexes. The behavioral role of this male secretion has not yet been elucidated.  相似文献   

20.
Racemic 4,4,4-trifluoro-3-(indole-3-)butyric acid (TFIBA) has been synthesized and shown to inhibitAvena coleoptile elongation. (S)-(+)-TFIBA (fig. 1), which was prepared by an enzymatic method and markedly promotes root growth of Chinese cabbage, lettuce and rice plants, is a novel fluorinated plant growth regulator. Activity of the (S)-(+)-enantiomer of TFIBA was 10-fold greater than that of the (R)-(–)-enantiomer in the first two plant species and 5-fold greater in rice.  相似文献   

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