Endothelial and smooth muscle properties of coronary and mesenteric resistance arteries in spontaneously hypertensive rats compared to WKY rats

Summary— To investigate if the functional alterations observed in resistance arteries of spontaneously hypertensive rats (SHRs) were also present at the coronary level, in vitro experiments were performed in mesenteric resistance arteries (MRA) and in right (RIC) and left interventricular coronary (LIC) arteries taken from 15–25-week-old SHR and age-matched Wistar Kyoto rats WKYs. Using a passive extension protocol, internal diameters corresponding to 100 mmHg intraluminal pressure (D₁₀₀) were determined and vessels were set up to a normalized internal diameter (0.9 D₁₀₀). SHR mesenteric resistance arteries had a significantly smaller diameter compared to WKY arteries, whereas both types of SHR coronary arteries had a greater diameter compared to those of WKY rats. In arteries in the absence of contracting agonist, nitro-L-arginine (NOLA, 100 μM) induced a progressive rise in basal tone, which could be reversed by subsequent addition of L-arginine (100 μM) but not D-arginine (100 μM). When expressed as percent of maximal contractions induced by agonists (noradrenaline, NA [10 μM] in MRA; serotonin, 5-HT [10 μM], in RIC and LIC), these contractions were significantly stronger in WKY compared to SHR coronary and mesenteric resistance arteries. In NA-precontracted MRA and 5HT-precontracted coronary arteries in the presence of indomethacin (10 μM), the magnitude of acetylcholine-induced maximal relaxations (expressed as percent of maximal contractions induced by agonists) was greater in WKY compared to SHR arteries. After a 30-min incubation period, NOLA (100 μM) completely inhibited relaxations induced by acetylcholine (0.01–10 μM) in all types of precontracted arteries. Subsequent additions of sodium nitroprusside, (SNP, 10 μM) induced complete relaxations in all preparations. These results show that a basal release of NO or NO-like compound by endothelial cells is present in isolated mesenteric resistance and coronary arteries of WKY rats and SHRs. The contribution of endothelium-derived relaxing factor-nitric oxide (EDRF-NO) to arterial tone was lower in MRA compared to coronary arteries in both strains and in SHR compared to WKY arteries. In the SHR preparations, the impaired relaxation induced by acetylcholine appeared to be due to a functional alteration of the endothelium in the presence of normal reactivity of the smooth muscle cells.     

表小檗碱对α受体的作用

表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择     

Immunophenotypic, genomic and clinical characteristics of blast crisis of chronic myelogenous leukaemia

We have studied phenotypic and clinical features in a consecutive series of 45 patients with chronic myelogenous leukaemia (CML) in blast crisis (BC). In addition, in 22 of these patients we have analysed the genotypic characteristics including immunoglobulin, T-cell receptor (TCR) and major breakpoint cluster region (M-bcr) gene organization. The granulomonocytic and megakaryoblastic lineages are the most commonly involved in these BC of CML (33% and 33% of cases, respectively); only 18% of our cases displayed a lymphoid phenotype. Moreover, both morphological and immunophenotypic studies revealed the frequent coexistence of two or three cell populations, especially when the megakaryoblast component is involved. The lymphoid BC displayed the highest incidence of complete remissions although this was not associated with a longer survival. Only minor differences between the different myeloid subgroups were observed. Immunoglobulin heavy chain (IgH) gene rearrangement was found in five of the six lymphoid BC and in one myeloid BC. Only one case showed k light chain gene rearrangement. In all but one myeloid BC the TCR-beta gene was in germline configuration. The TCR-gamma gene was rearranged in all lymphoid and one myeloid BC, while TCR-delta gene rearrangement was detected in 67% and 16% of the lymphoid and myeloid BC, respectively. Most of the lymphoid BC (4/5) had the M-bcr breakpoint in subregion 3, while the myeloid BC had the breakpoint either in subregion 2 or 3. No differences between the different myeloid phenotypic subgroups were observed in relation to breakpoint.     

Assessment of Multimeric Structure and Ristocetin-Induced Binding to Platelets of Von Willebrand Factor Present in Cryoprecipitate and Different Factor VIII Concentrates

The multimeric structure of von Willebrand factor (vWF) and its ristocetin-induced binding to platelets, using a simple and very sensitive radiomonoclonal antibody-labeled vWF method, was compared in normal plasma, single-donor cryoprecipitate (CP) and five different antihemophilic factor (AHF) concentrates. All the AHF showed a lack of larger vWF multimers, an abnormal 'triplet' pattern, and much lower vWF binding to platelets than that of plasma or CP, vWF being the lowest for those with a lesser proportion of larger vWF multimers. These results suggest that the combination of vWF multimeric analysis and the radiomonoclonal-labeled vWF method may be very useful in the assessment of AHF preparations.     

Acute peripheral arterial and graft occlusion: treatment with selective infusion of urokinase and lysyl plasminogen

Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs.     

Decreased serum levels of nutritional biochemical indices in healthy children with marginally delayed physical growth

Biochemical markers of nutritional status (albumin, transthyretin, insulin-like growth factor-I and zinc) were measured in slowly growing two- to five-year-old, low-income Parisian children whose weight-for-height or height-for-age z scores (WHZ or HAZ) were between — 1 and — 2 SD of the NCHS median. The results were compared to controls who were matched for age, sex, and ethnic origin with WHZ and HAZ between — 1 and + 2 SD. Mean serum levels of transthyretin, albumin and insulin-like growth factor-I and mean plasma zinc concentrations were significantly lower in the growth-impaired children than in the controls ( p = 0.002, p = 0.006, p = 0.015, and p = 0.035, respectively). While the height-retarded children had low mean serum insulin-like growth factor-I values, the weight-retarded subjects had decreased levels of albumin, transthyretin and zinc when compared to controls. Lower mean levels of nutritional markers in healthy, slowly growing children suggest that inadequate dietary intakes of zinc, protein and/or energy may result in marginal delays in weight and height gains.