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The insulin-like growth factor (IGF) signaling system includes the growth factors and their cell surface receptors, along with circulating IGF binding proteins (IGFBPs) that may alter and modulate the action of these neurotrophic hormones. These IGFBPs, along with IGFs and receptors, have been detected in various tissues including the brain. In this study, using polyclonal antibody to human IGFBP-1 or bovine IGFBP-2, we found that mouse muscle extracts contain similar-sized proteins that cross-react with these antibodies on Western immunoblots. After establishing that these antibodies reacted with the homologous murine IGFBPs, we performed immunocytochemistry to demonstrate the localization of IGFBP-1 at the neuromuscular junction, a model nicotinic, cholinergic synapse, as well as within intramuscular nerves. IGFBP-2, a distinct macromolecule, is present on the surface of muscle fibers and is not present within synapses or nerves. 相似文献
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BACKGROUND: Different regions within the left ventricle are preferentially supplied by the left or right sympathetic system. In order to characterize different influences of left vs right sympathetic lateralization on LV function, haemodynamic effects of right and left stellate ganglion stimulations (RSGS and LSGS) as well as a right sympathetic block (RSB) were compared. METHODS: Seven alpha-chloralose anaesthetized open chest dogs were instrumented for measurement of LV pressure (tip manometers) and regional LV wall thickness (WT, sonomicrometry) in the antero-apical wall (AW, innervated by right stellate ganglion) and postero-basal wall (PW, left stellate ganglion). Timing of regional myocadial wall motion was evaluated by the phase of the first Fourier transform of the WT signals, LV asynchrony by the phase difference (phi) between both regions, and LV diastolic function by the time constant of isovolumic relaxation (tau). Measurements were performed before and after RSB (5 ml of lidocaine 1%); in 6 dogs of this group, RSGS and LSGS (4 V, 0.2 ms, 20 Hz) were performed before RSB. In order to investigate a regional inotropic stimulation without systemic effect, 6 additional dogs received intracoronary noradrenaline injections (NIC, 0.25 microgram) into the left circumflex artery perfused myocardium. RESULTS: LSGS and NIC led to an earlier PW-motion within the cardiac cycle (phase reduction by 40.0 +/- 15.0 degree (SEM) and 55.5 +/- 11.2 degrees) and RSGS induced an earlier AW-motion (by 33.7 +/- 15.2 degrees). After RSB, AW-motion was delayed (38.1 +/- 9.2 degrees). The consequence was an asynchronous wall motion pattern after all interventions (change in phi: LSGS-64.7 +/- 18.7 degrees, RSGS 41.1 +/- 15.7 degrees, NIC -74.5 +/- 17.4 degrees, RSB -52.6 +/- 14.6 degrees), and a prolonged relaxation (tau increase: RSGS 9.4 +/- 1.9, NIC 8.3 +/- 1.5, RSB 3.7 +/- 0.8 ms). CONCLUSION: Unilateral increases as well as decreases of sympathetic tone to the heart result in an asynchronous wall motion pattern and an impaired LV relaxation. 相似文献
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NA Sharif SX Xu ST Miller DA Gamache JM Yanni 《Canadian Metallurgical Quarterly》1996,278(3):1252-1261
Olopatadine (AL-4943A; KW-4679) [(Z)-11-[3-(dimethylamino)propylidene]-6, 11-dihydrodibenz[b,e]oxepine-2-acetic acid hydrochloride] is an antiallergic/antihistaminic drug under development for topical ocular use. The effects of the compound on release of proinflammatory mediators (histamine, tryptase and prostaglandin D2) from monodispersed human conjunctival mast cells were assessed. Histamine receptor subtype binding affinities and functional potencies were determined with ligand binding and phosphoinositide turnover assays, respectively. Olopatadine inhibited the release of histamine, tryptase and prostaglandin D2, in a concentration-dependent manner (IC50 = 559 microM). Evaluation of the interaction of olopatadine with histamine receptors revealed a relatively high affinity for the H1 receptor (Ki = 31.6 nM, pKi = 7.5 +/- 0.1, n = 7) but lower affinities for H2 receptors (Ki = 100 microM, pKi = 4.0 +/- 0.19, n = 7) and H3 receptors (Ki = 79.4 microM, pKi = 4.1 +/- 0.16, n = 7). The H1 selectivity of olopatadine was superior to that of other ocularly used antihistamines studied, such as ketotifen, levocabastine, antazoline and pheniramine. The profiling of olopatadine in 42 nonhistamine receptor binding assays revealed that olopatadine interacts with only two nonhistamine receptor/uptake sites to any significant degree (pIC50 < or = 5-6). Olopatadine inhibited histamine-induced phosphoinositide turnover in human conjunctival epithelial cells (IC50 = 10 nM, pIC50 = 8.0, n = 4) and in other human ocular cells (IC50 = 15.8-31.6 nM, pIC50 = 7.5-7.8) and exhibited apparent noncompetitive antagonist properties in these cells, with an estimated dissociation constant (Kb) of 19.9 nM (pKb = 7.7, n = 6). This combination of mast cell mediator release inhibition and selective H1 receptor antagonism suggests that olopatadine may be particularly useful in the treatment of ocular allergic diseases. Indeed, olopatadine has recently shown clinical efficacy in an allergic conjunctivitis model in human subjects. 相似文献
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SX Cai SM Kher ZL Zhou V Ilyin SA Espitia M Tran JE Hawkinson RM Woodward E Weber JF Keana 《Canadian Metallurgical Quarterly》1997,40(5):730-738
We report on a series of alkyl- and alkoxy-substituted 1,4-dihydroquinoxaline-2,3-diones (QXs), prepared as a continuation of our structure-activity relationship (SAR) study of QXs as antagonists for the glycine site of the N-methyl-D-aspartate (NMDA) receptor. The in vitro potency of these antagonists was determined by displacement of the glycine site radioligand [3H]-5,7-dichlorokynurenic acid ([3H]DCKA) in rat brain cortical membranes. In general, methyl is a good replacement for chloro or bromo in the 6-position, and alkoxy-substituted QXs have lower potencies than alkyl- or halogen-substituted QXs. Ethyl-substituted QXs are generally less potent than methyl-substituted QXs, especially in the 6-position of 5,6,7-trisubstituted QXs. Fusion of a ring system at the 6,7-positions results in QXs with low potency. Several methyl-substituted QXs are potent glycine site antagonists that have surprisingly high in vivo activity in the maximal electroshock (MES) test in mice. Among these, 7-chloro-6-methyl-5-nitro QX (14g) (IC50 = 5 nM) and 7-bromo-6-methyl-5-nitro QX (14f) (IC50 = 9 nM) are comparable in potency to 6,7-dichloro-5-nitro QX (2) (ACEA 1021) as glycine site antagonists. QX 14g has an ED50 value of 1.2 mg/kg iv in the mouse MES assay. Interestingly, alkyl QXs with log P values of 0.5 or less tend to be more bioavailable than QXs with higher log P values. QX 14g has 440-fold selectivity for NMDA vs alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, as determined electrophysiologically under steady-state conditions in oocytes expressing rat cerebral cortex poly(A)+ RNA. Overall, 14g was found to have the best combination of in vitro and in vivo potency of all the compounds tested in this and previous studies on the QX series. 相似文献
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The regulation of would healing is one of the most important fields of research in ophthalmology today. Rabbit corneal fibroblast cultures were used to study the effects of interleukin-1 (IL-1) blockers on the proliferation of fibroblasts which is closely related to the wound healing. It was found that IL-1 blockers, such as CK-17, CK-101A, CK-2 and CK-103A, suppress fibroblast proliferation in a concentration-dependent manner. DNA synthesis was significantly inhibited by CK-17 and CK-103A but not by CK-101A and CK1-102. Although the synthesis of mRNA was reduced by all CK-compounds at most concentration tested, the synthesis of protein was only slightly reduced or unaffected. These results indicate that CK-compounds are potent fibroblast inhibitors but not cytolytic agents. 相似文献
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Observational studies were conducted on the biological characteristics of Ligusticum chuanxiong, such as suitable growth environment, growing period, growth of stems, leaves and rhizomes, yield structure, etc. The specific regularities of each growth period were also studied. 相似文献
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SL Washington MS Yoon AM Chagovetz SX Li CA Clairmont BD Preston KA Eckert JB Sweasy 《Canadian Metallurgical Quarterly》1997,94(4):1321-1326
Hemagglutinins were determined in six species of mosquitoes that are susceptible and refractory to Brugia malayi (Filarioidea: Nematoda). High titers of hemagglutinins were found in the salivary gland extract and in the body fluid of a completely refractory species, Aedes taeniorhynchus, and in partially refractory species, Anopheles quadrimculatus but low levels of hemagglutinins were also present in the body fluid of Aedes aegypti (Black-eye, Liverpool strain), a susceptible species. Hemagglutinating activity was not found in the other three completely refractory species of mosquitoes, Culex quinquefasciatus, Culex nigripalpus, and Aedes albopictus in which blood coagulated rapidly after ingestion. High titers of hemagglutinins in the salivary glands of Ae. taeniorhynchus and An. quadrimaculatus facilitated rapid movement of sheathed microfilariae from the midgut to the hemocoel. It is suggested that high titers of hemagglutinins present in the hemocoel bound to the glycoconjugates with exposed carbohydrate moieties present on the microfilarial sheaths and developing abnormal larvae (L1) in the thoracic muscle cells. These hemagglutinin-bound glycoconjugates formed capsules that subsequently stimulated the immune response and resulted in melanization of microfilarial sheaths and sheathed microfilariae in the hemocoel and intracellularly developing abnormal L1 in the thoracic muscles. Only minimal encapsulation and melanization of B. malayi microfilariae was observed in the hemocoel of the other four species of mosquitoes that lacked hemagglutinins in the salivary glands. The results suggest that tissue specific hemagglutinins are one of several factors of vector susceptibility/refractoriness through immune reactions (encapsulation, activation of prophenoloxidases). 相似文献
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LL von Moltke DJ Greenblatt DA Ciraulo JM Grassi BW Granda SX Duan JS Harmatz RI Shader 《Canadian Metallurgical Quarterly》1998,18(4):338-341
BACKGROUND: We compared our results with bullous vs diffuse emphysema by performing a bilateral thoracoscopic stapled volume reduction technique in 15 patients (age 45-80, 10 males, five females). METHODS: Eight patients demonstrated bullous emphysema and seven patients diffuse emphysema. Lung reduction was performed with a bilateral thoracoscopic stapled technique utilizing bovine pericardium in the supine position. RESULTS: Comparison of the bullous versus diffuse groups revealed no significant differences in means for the following variables: length of air leak (7.5 vs 3.3 days); length of stay (8.1 vs 6.5 days); pre-op FEV1, (23% vs 22%); pre-op dyspnea index (3.4 vs 3.6). At 3 months the bullous subset had a highly significant improvement (p < 0.007) in FEV1 (88%) compared with the diffuse subset FEV1 (59%). CONCLUSIONS: These early results suggest that patients with bullous emphysema are at no greater risk and demonstrate a significantly greater improvement in FEV1 than patients with diffuse emphysema. 相似文献
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Based on the characteristics of respiration and the intrathoracic pressure in Qigong (Q-G) maneuvering, it has been theorized that the Q-G maneuver may lessen the lack of coordination between aircraft oxygen apparatus and anti-G maneuvers and may be more compatible with positive pressure breathing (PPB). In an experiment intended to test this hypothesis, 5 male volunteers, trained in Q-G and L-1 maneuvers, performed the Q-G and the L-1 maneuvers without and with (PPB) at 4 and 6 kPa, respectively, with 14 respiratory parameters being measured. The results demonstrated that, when performing Q-G maneuver, the maximal expiratory flow rate averaged 1.175-1.645 L.s-1, the inspiratory peak flow, 1.003-1.297 L.s-1. Both these values were markedly lower than those of the L-1 maneuver, and matched well the performance of current aircraft oxygen apparatus. From the blood pressure and heart rate values, it is evident that PPB can further promote the blood pressure-raising effect of the Q-G maneuver, and alleviate pilots' fatigue. 相似文献