In vivo EMG biofeedback in violin and viola pedagogy

In vivo EMG biofeedback was found to be an effective pedagogical tool for removing unwanted left-hand tension in nine violin and viola players. Improvement occurred rapidly and persisted throughout a 5-month follow-up period. Further studies will be necessary to assess the effect of biofeedback independent of placebo effects. The brevity of the method and the magnitude of improvement warrant further investigation.     

The Oral History and Literature of the Wolof People of Waalo, Northern Senegal

The Oral History and Literature of the Wolof People of Waalo, Northern Senegal. Samba Diop. Lewiston, Canada; Edwin Mellen Press, 1995. 389 pp.     

Thrombin attenuates the stimulatory effect of histamine on Ca2+ entry in confluent human umbilical vein endothelial cell cultures

Human umbilical vein endothelial cells were grown to confluence, as first passage cells, on coverslips. Treatment with ionomycin or histamine caused a sustained rise in intracellular Ca2+ (measured by Fura-2 fluorescence), but after treatment with thrombin, only a transient rise in Ca2+ was observed. Furthermore, the addition of thrombin after ionomycin or histamine lowered the raised Ca2+ back to near control levels. This effect of thrombin was concentration dependent, with increasing concentrations producing increases in both the rate and extent of the lowering of Ca2+. A similar effect of thrombin was seen on video imaging of Fura-2-loaded cell monolayers. The Ca2(+)-lowering effect of thrombin was not mimicked by phorbol 12-myristate 13-acetate nor blocked by staurosporine, indicating a lack of involvement of protein kinase C; intracellular pH also does not appear to be involved. The mechanism by which thrombin lowers cytoplasmic Ca2+ is due mainly to inhibition of Ca2+ entry since thrombin prevented the stimulated influx of Mn2+ caused by histamine or ionomycin. It may therefore be that in vivo under certain physiological or pathological conditions, thrombin's effects on intracellular Ca2+ are more transient than those of histamine, and thrombin also may induce transience in histamine's actions.     

The stimulation of the brain alkaline phospholipase A1 attacking phosphatidylethanolamine by various salts and metal chelators

Rat brain contains a soluble, high molecular weight phospholipase A₁ of alkaline pH optimum which shows a preference for phosphatidylethanolamine as substrate. There is evidence that the same enzyme exists in liver and kidney. At low osmotic concentrations of buffer the enzyme is markedly stimulated by CaCl₂. However, MgCl₂ and MnCi₂ are equally as effective although at concentrations above 2 mM the activation falls away with MnCl₂. The phospholipase A₁ is stimulated by divalent metal ion chelators (EDTA, EGTA, CDTA) and by sodium phosphate and sodium sulphate. The activity is inhibited by hexanol, benzyl alcohol, diethylether and detergents. Although the activity can be inhibited by saturated and unsaturated fatty acids, no evidence could be obtained that the activators function by counteracting the inhibitory action of fatty acids liberated at the interface of the substrate and incubation medium. It is suggested that to achieve good enzymic hydrolysis a certain type of organised hydrated phosphatidylethanolamine structure is required in which the negative zeta potential has been reduced by metallic cations in the incubation medium.This paper is dedicated to Dr. Derek Richter on his seventy-fifth birthday.     

Clearance of bacteria and non-antigenic markers following intra-uterine inoculation into maiden mares: Effect of steroid hormone environment

Uterine response to inoculation with Streptococcus zooepidemicus organisms (antigenic markers) and 15-mum microspheres and charcoal (non - antigenic markers) was determined in seasonally acyclic maiden mares treated with either progesterone (P) n = 4, estradiol (E) n = 4 or oil vehicle (C) n = 4. At 3, 7 and 15 d after inoculation with bacteria and the 2 non - antigenic markers, uteri were flushed and the clearance of these materials, as well as the number of white blood cells and immunoglobulin concentration, determined. P-treated mares had higher numbers of bacteria and IgA and a greater volume of purulent fluid in the uterus than E- or C-treated mares at 7 d after inoculation. Clearance of inoculated materials began within 2 h in E-treated mares, and the non-antigenic markers were completely cleared in E- and C-, but not in P-treated mares, in 3 d. This suggests that in the P-dominated uterus, reduced physical clearance may contribute to an increased susceptibility to uterine infection.     

Rhodanine derivatives as novel inhibitors of PDE4

The discovery, synthesis and in vitro activity of a novel series of rhodanine based phosphodiesterase-4 (PDE4) inhibitors is described. Structure-activity relationship studies directed toward improving potency led to the development of submicromolar inhibitors 2n and 3i (IC(50)=0.89 & 0.74 microM). The replacement of rhodanine with structurally related heterocycles was also investigated and led to the synthesis of pseudothiohydantoin 7 (IC(50)=0.31 microM).