Comparative trial of volunteer and professional treatments of dysphasia after stroke.

A study of the treatment of dysphasia after stroke compared the progress of two groups of disabled patients. One received conventional treatment from qualified speech therapists and the other from non-professional volunteers. Methods of assessing communication difficulties were also compared and the impact of aphasic illness on families examined. No important differences in the results of treatment were seen between the two groups. The volunteers, however, often had to assume some of the responsibilities of social workers, and transport to hospital created practical and economic problems. It is concluded that the two forms of treatment provide essentially the same benefit, although doubt must still remain because relatively few patients were studied.     

Arbitration Agreements and Your Malpractice Coverage

With new legislation and favorable case law developments, many providers of health care services are turning to binding arbitration agreements as a partial solution to the medical malpractice crisis. Existing data indicate tremendous advantages can be gained from the use of such agreements, if they are carefully drawn to comply with new law, tailored to the particular situation in which they will be used and coupled with appropriate procedures to secure the intended benefits.Arbitration is not a substitute for insurance, but if a provider has taken the calculated risk of forgoing insurance he should not be without a carefully drawn binding arbitration agreement.     

Purification and some properties of the phosphoprotein from rat incisors.

The phosphoprotein of rat incisors has been purified by successive gel and ion-exchange chromatography. The product gave a single band on polyacrylamide gel electrophoresis and contained approximately 34% phosphoserine and 32% aspartic acid. Alkaline elimination experiments showed all the phosphate to be present as phosphoserine. Ultraviolet spectra in the presence or absence of ATP showed that the phosphoprotein did not contain an nucleotide moiety as suggested by Veis, A., Spector, A. R. and Zamoscianyk, H. ((1972) Biochim. Biophys. Acta 257, 404-413) for bovine dentin phosphoprotein.     

The effect of a myelin apoprotein on lipid structure: a spin probe study.

Spin probes, stable free radical derivatives of stearic acid and cholestanone, were used to observe the effects of the "Folch-Lees" protein isolated from the white matter of bovine brain on the organization and motion of lipid molecules. The incorporation of the organic solvent soluble form of this protein decreased the tendency of a variety of lipid molecules with zero, positive or negative net charges to arrange themselves close to the normal to the lipid bilayer. The aqueous form of the protein also had a profound chaotropic effect on the molecular geometry of the lipid, but only if the lipids had a net negative charge (the protein has a net positive charge in the pH range investigated). Examination of the ESR spectra indicated that this protein altered the geometry of the lipid structure without causing major changes in the mobility of the individual lipid molecules.     

Uridine diphosphoglucose dehydrogenase in the intervertebral disc

Synopsis Intervertebral discs of an old sheep and a young pig were examined for the presence of cells containing the enzyme uridine diphosphoglucose dehydrogenase. In the sheep, the inner anulus had a higher proportion of active cells than the outer anulus; in the pig, there was no difference. From a consideration of cell numbers, it is suggested that there is an accumulation of glycosaminoglycans in the centre of the disc rather than an increased production rate. Notochordal cells in the pig disc contain uridine diphosphoglucose dehydrogenase and are capable of producing glycosaminoglycans.     

Noninvasive Neutron Scattering Measurements Reveal Slower Cholesterol Transport in Model Lipid Membranes

Proper cholesterol transport is essential to healthy cellular activity and any abnormality can lead to several fatal diseases. However, complete understandings of cholesterol homeostasis in the cell remains elusive, partly due to the wide variability in reported values for intra- and intermembrane cholesterol transport rates. Here, we used time-resolved small-angle neutron scattering to measure cholesterol intermembrane exchange and intramembrane flipping rates, in situ, without recourse to any external fields or compounds. We found significantly slower transport kinetics than reported by previous studies, particularly for intramembrane flipping where our measured rates are several orders of magnitude slower. We unambiguously demonstrate that the presence of chemical tags and extraneous compounds employed in traditional kinetic measurements dramatically affect the system thermodynamics, accelerating cholesterol transport rates by an order of magnitude. To our knowledge, this work provides new insights into cholesterol transport process disorders, and challenges many of the underlying assumptions used in most cholesterol transport studies to date.     

Comparison of growth limits of Listeria monocytogenes in milk,broth and cheese

Aim: To determine growth initiation differences of Listeria monocytogenes between a cheesemaking context, milk and tryptic soy broth (TSB). Methods and Results: A laboratory‐scale cheese was made with a mix of two strains of L. monocytogenes at four initial pH values, five water activity (a_w) values and two contamination levels at 30°C. Counts of L. monocytogenes were determined at time 0 and after 8 h of cheese manufacture. Milk and TSB at the same pH and a_w conditions were inoculated with the L. monocytogenes mix in multi‐well plates. Growth was determined by plating each well onto Agosti & Ottaviani Listeria Agar after 8 h of incubation at 30°C. Each condition was repeated six times, and growth initiation probability was modelled with logistic regression models. Growth initiation boundaries were obtained for each matrix type. The results showed that the growth limits were matrix dependent. In the three matrix types, a_w was the most important factor affecting the probability of growth initiation. Contamination level affected growth TSB and cheesemaking conditions. Conclusions: The interface wideness and position in cheese, milk and TSB were dissimilar, indicating that the use of models evaluated in TSB or milk could not be used to predict the behaviour of L. monocytogenes under cheesemaking conditions. Significance and Impact of the Study: Predictive models generated in liquid media are not necessarily adaptable to solid food, and the generation of real food models is necessary.     

Redox-active antioxidant modulation of lipid signaling in vascular endothelial cells: vitamin C induces activation of phospholipase D through phospholipase A2, lipoxygenase, and cyclooxygenase

We have earlier reported that the redox-active antioxidant, vitamin C (ascorbic acid), activates the lipid signaling enzyme, phospholipase D (PLD), at pharmacological doses (mM) in the bovine lung microvascular endothelial cells (BLMVECs). However, the activation of phospholipase A(2) (PLA(2)), another signaling phospholipase, and the modulation of PLD activation by PLA(2) in the ECs treated with vitamin C at pharmacological doses have not been reported to date. Therefore, this study aimed at the regulation of PLD activation by PLA(2) in the cultured BLMVECs exposed to vitamin C at pharmacological concentrations. The results revealed that vitamin C (3-10 mM) significantly activated PLA(2) starting at 30 min; however, the activation of PLD resulted only at 120 min of treatment of cells under identical conditions. Further studies were conducted utilizing specific pharmacological agents to understand the mechanism(s) of activation of PLA(2) and PLD in BLMVECs treated with vitamin C (5 mM) for 120 min. Antioxidants, calcium chelators, iron chelators, and PLA(2) inhibitors offered attenuation of the vitamin C-induced activation of both PLA(2) and PLD in the cells. Vitamin C was also observed to significantly induce the formation and release of the cyclooxygenase (COX)- and lipoxygenase (LOX)-catalyzed arachidonic acid (AA) metabolites and to activate the AA LOX in BLMVECs. The inhibitors of PLA(2), COX, and LOX were observed to effectively and significantly attenuate the vitamin C-induced PLD activation in BLMVECs. For the first time, the results of the present study revealed that the vitamin C-induced activation of PLD in vascular ECs was regulated by the upstream activation of PLA(2), COX, and LOX through the formation of AA metabolites involving oxidative stress, calcium, and iron.     

cGMP/Protein Kinase G Signaling Suppresses Inositol 1,4,5-Trisphosphate Receptor Phosphorylation and Promotes Endoplasmic Reticulum Stress in Photoreceptors of Cyclic Nucleotide-gated Channel-deficient Mice

Photoreceptor cyclic nucleotide-gated (CNG) channels play a pivotal role in phototransduction. Mutations in the cone CNG channel subunits CNGA3 and CNGB3 are associated with achromatopsia and cone dystrophies. We have shown endoplasmic reticulum (ER) stress-associated apoptotic cone death and increased phosphorylation of the ER Ca²⁺ channel inositol 1,4,5-trisphosphate receptor 1 (IP₃R1) in CNG channel-deficient mice. We also presented a remarkable elevation of cGMP and an increased activity of the cGMP-dependent protein kinase (protein kinase G, PKG) in CNG channel deficiency. This work investigated whether cGMP/PKG signaling regulates ER stress and IP₃R1 phosphorylation in CNG channel-deficient cones. Treatment with PKG inhibitor and deletion of guanylate cyclase-1 (GC1), the enzyme producing cGMP in cones, were used to suppress cGMP/PKG signaling in cone-dominant Cnga3^−/−/Nrl^−/− mice. We found that treatment with PKG inhibitor or deletion of GC1 effectively reduced apoptotic cone death, increased expression levels of cone proteins, and decreased activation of Müller glial cells. Furthermore, we observed significantly increased phosphorylation of IP₃R1 and reduced ER stress. Our findings demonstrate a role of cGMP/PKG signaling in ER stress and ER Ca²⁺ channel regulation and provide insights into the mechanism of cone degeneration in CNG channel deficiency.