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61.
62.
The effects of left- and right-sided hemispheric brain infarction on variability in circadian blood pressure and cardiovascular measures were investigated in 35 patients to test for asymmetry of the sympathetic consequences of stroke. No significant differences regarding age, size of infarction or extent and frequency of damage to the insular cortex could be detected between the two groups. Patients with right-sided infarction showed a significantly reduced circadian blood pressure variability [diastolic: -1% (95% CI -4 to 1) vs -6% (-9 to -2);P < 0.05] and a higher frequency of nocturnal blood pressure increase (47% vs 35%;P < 0.05) as compared with patients with left-sided infarction. Right-sided infarction was also associated with higher serum noradrenaline concentrations [546 pg/ml (95% CI 415–677) vs 405 pg/ml (266–544);P < 0.05], and ECG more frequently showed QT prolongation (53% vs 35%;P < 0.05) and cardiac arrhythmias (67% vs 20%;P < 0.005). However, irrespective of the hemisphere damaged, patients with insular infarction showed the most pronounced changes of these parameters. In addition, two patients with right-sided strokes (13%) involving the insula, but none with a left-sided infarction, developed myocardial infarction. These findings suggest lateralization of sympathetic activation with right-sided dominance for sympathetic effects following hemispheric stroke.Supported by the Friedrich-Schiedel-Stiftung 相似文献
63.
Josephine Shallo-Hoffmann Dirk Watermeier Jürgen Petersen Hermann Mühlendyck 《Neurosurgical review》1988,11(2):151-158
Verification of inheritance in congenital nystagmus (CN) is only possible through the identification of more than one affected member in a family, since in a single case there are no accurate clinical differentiations between spontaneous and inherited CN. We performed electronystagmographic examinations (ENG) to search for abnormal involuntary eye movements as a sign of heredity in seemingly unaffected members of CN families.ENG registrations were performed under three test conditions: (1) with the subject fixating a target, (2) with the room lights off and (3) with closed eyes.Fifty normally sighted individuals (group (a) underwent the test procedure to provide a baseline of normality. Five CN families (three dominant, two sex-linked recessive) were tested as group (b). The eye movement recordings were analysed in terms of nystagmus intensity (amplitude x frequency of the involuntary saccade). In every one of the five families, abnormalities in seemingly non-affected members could be demonstrated: in four families, fastphase instabilities, in the fifth family a true (CN) (slowphase instability).All certain gene carriers were diagnosed correctly by the ENG.These findings indicate a method for detecting slightly affected members in dominant pedigrees and female gene carriers in sex-linked mode of transmission. 相似文献
64.
Martin J. Lohse Bernice Elger Jutta Lindenborn-Fotinos Karl-Norbert Klotz Ulrich Schwabe 《Naunyn-Schmiedeberg's archives of pharmacology》1988,337(1):64-68
Summary Human platelet membranes were solubilized with the zwitterionic detergent CHAPS (3-[3-(cholamidopropyl)dimethylammonio]-1-propanesulfonate) and the solubilized extract subjected to gel filtration. Binding of the adenosine receptor agonist [3H]NECA (5-N-ethylcarboxamidoadeno-sine) was measured to the eluted fractions. Two [3H]NECA binding peaks were eluted, the first of them with the void volume. This first peak represented between 10% and 25% of the [3H]NECA binding activity eluted from the column. It bound [3H]NECA in a reversible, saturable and GTP-dependent manner with an affinity of 46 nmol/1 and a binding capacity of 510 fmol/mg protein. Various adenosine receptor ligands competed for the binding of [3H]NECA to the first peak with a pharmacological profile characteristic for the A2 adenosine receptor as determined from adenylate cyclase experiments. In contrast, most adenosine receptor ligands did not compete for [3H]NECA binding to the second, major peak. These results suggest that a solubilized A2 receptor-GS protein complex of human platelets can be separated from other [3H]NECA binding sites by gel filtration. This allows reliable radioligand binding studies of the A2 adenosine receptor of human platelets.Abbreviations CHAPS
3-[3-(cholamidopropyl)dimethylammoniol-l-propanesulfonate
- CIA
2-chloroadenosine
- CPA
N6-cyclopentyladenosine
- DPX
1,3-diethyl-8-phenylxanthine
- NECA
5-N-ethylcarboxamidoadenosine
- PAA
2-phenylaminoadenosine
- PIA
N6-phenyhsopropyladenosine
- XAC
8-{4-[([{(2-aminoethyl)amino}carbonyl}methyl)oxy]phenyl]-1,3-dipropylxanthine
Send offprint requests to M. J. Lohse 相似文献
65.
Karl-Norbert Klotz Martin J. Lohse Ulrich Schwabe Gloria Cristalli Sauro Vittori Mario Grifantini 《Naunyn-Schmiedeberg's archives of pharmacology》1989,340(6):679-683
Summary The tritiated analogue of 2-chloro-N6-cyclopentyladenosine (CCPA), an adenosine derivative with subnanomolar affinity and a 10000-fold selectivity for A1 adenosine receptors, has been examined as a new agonist radioligand. [3H]CCPA was prepared with a specific radioactivity of 1.58 TBq/mmol (43 Ci/mmol) and bound in a reversible manner to A1 receptors from rat brain membranes with a high affinityK
D-value of 0.2 nmol/l. In the presence of GTP aK
D-value of 13 nmol/l was determined for the low affinity state for agonist binding. Competition of several adenosine receptor agonists and antagonists for [3H]CCPA binding to rat brain membranes confirmed binding to an A1 receptor. Solubilized A1 receptors bound [3H]CCPA with similar affinity for the high affinity state. At solubilized receptors a reduced association rate was observed in the presence of MgCl2, as has been shown for the agonist [3H]N6-phenylisopropyladenosine ([3H]PIA). [3H]CCPA was also used for detection of A1 receptors in rat cardio myocyte membranes, a tissue with a very low receptor density. A KD-value of 0.4 nmol/l and aB
max-value of 16 fmol/ mg protein was determined in these membranes. In human platelet membranes no specific binding of [3H]CCPA was measured at concentrations up to 400 nmol/l, indicating that A2 receptors did not bind [3H]CCPA. Based on the subnanomolar affinity and the high selectivity for A1 receptors [3H]CCPA proved to be a useful agonist radioligand for characterization of A1 adenosine receptors also in tissues with very low receptor density.Abbreviations CHA
N6-cyclopenyadenosine
- CPA
N6-cy-clopentyladen,osine
- CCPA
2-chloro-N6-cyclopentyladenosine
- CCCPA
2-chloro-5-chloro-5-deoxy-N6-cyclopentyladenosine;
- CHAPS
3-[3-(cholamidopropyl)dimethylammonio]-1-propanesulfonate
- DPCPX
8-cyclopentyl-1,3-dipropylxanthine
- NECA
N-ethylcarboxamidoadenosine
- PEI
polyethylenimine
- PIA
N6-phenylisopropyladenosine
Send offprint requests to K.-N. Klotz at the above address 相似文献
66.
67.
CD1 assembly and the formation of CD1-antigen complexes 总被引:2,自引:0,他引:2
Hava DL Brigl M van den Elzen P Zajonc DM Wilson IA Brenner MB 《Current opinion in immunology》2005,17(1):88-94
The CD1 antigen presentation system presents lipid antigens to effector T cells, which have diverse roles in antimicrobial responses, antitumor immunity and in regulating the balance between tolerance and autoimmunity. The trafficking of CD1 molecules and lipid antigens facilitates their intersection and binding in specific intracellular compartments. Recent studies have now identified unexpected accessory molecules that are critical to CD1 assembly and lipid loading. The atomic structures of CD1-antigen complexes have defined both the orientation of polar headgroups between the alpha1 and alpha2 helices of CD1 and the manner in which distinct CD1 isoforms bind a range of lipids that have different lengths and numbers of hydrocarbon chains. 相似文献
68.
Deckert M Lütjen S Leuker CE Kwok LY Strack A Müller W Wagner N Schlüter D 《European journal of immunology》2003,33(5):1418-1428
Under various inflammatory conditions, cell adhesion molecules are up-regulated in the central nervous system (CNS) and may contribute to the recruitment of leukocytes to the brain. In the present study, the functional role of vascular cell adhesion molecule (VCAM)-1 in Toxoplasma encephalitis (TE) was addressed using VCAM(flox/flox MxCre) mice. Neonatal inactivation of the VCAM-1 gene resulted in a lack of induction of VCAM-1 on cerebral blood vessel endothelial cells, whereas the constitutive expression of VCAM-1 on choroid plexus epithelial cells and the ependyma was unaffected; in these animals, resistance to T. gondii was abolished, and VCAM(flox/flox MxCre) mice died of chronic TE caused by a failure to control parasites in the CNS. Although leukocyte recruitment to the CNS was unimpaired, the B cell response was significantly reduced as evidenced by reduced serum levels of anti-T. gondii-specific IgM and IgG antibodies. Furthermore, the frequency and activation state of intracerebral T. gondii-specific T cells were decreased, and microglial activation was markedly reduced. Taken together, these data demonstrate the crucial requirement of VCAM-1-mediated immune reactions for the control of an intracerebral infectious pathogen, whereas other cell adhesion molecules can efficiently compensate for VCAM-1-mediated homing across cerebral blood vessels. 相似文献
69.
Ossewaarde ME Bots ML van der Schouw YT de Kleijn MJ Wilmink HW Bak AA Planellas J Banga JD Grobbee DE 《Maturitas》2003,45(1):47-54
OBJECTIVES: To determine whether improvement in endothelial function of the brachial artery observed in women treated with hormone replacement therapy (HRT) may be explained by changes in lipid profile or blood pressure, information was used obtained in a single-centre, randomised, double blind, placebo-controlled trial. METHODS: Hundred-and-five healthy postmenopausal women, aged 50-65 years, were treated with 0.625 mg conjugated equine estrogens (CEE) combined with 2.5 mg medroxyprogesterone acetate (MPA) (CEE+MPA), 2.5 mg tibolone or placebo for 3 months. At baseline and after 3 months, endothelial function was assessed using flow-mediated dilatation (FMD) and nitro glycerine-mediated dilatation (NMD). Furthermore, lipids were measured. Multivariate linear regression analysis was applied to address the research question. RESULTS: Treatment with CEE+MPA resulted in an improvement in FMD of 2.0% (95% CI: -0.1; 4.1). CEE/MPA reduced total cholesterol with 13% (95% CI: -18%; -7%), LDL-cholesterol with 23% (95% CI: -30%; -15%) and lipoprotein(a) (Lp(a)) with 14% (95% CI: -26%; -2%). The magnitude of the relation of CEE/MPA with endothelial function was attenuated to from 2.0 to 1.6% when change in Lp(a) was taken into account. Adjustments for other lipids or blood pressure did not attenuate the association. CONCLUSIONS: The improvement in endothelial function in postmenopausal women treated with CEE+MPA appears to be partially mediated by change in Lp(a), and apparently not by changes in other lipids. 相似文献
70.