Behavioral deficits and cholinergic pathway abnormalities in male Sanfilippo B mice.

Sanfilippo B syndrome is a progressive neurological disorder caused by inability to catabolize heparan sulfate glycosaminoglycans. We studied neurobehavior in male Sanfilippo B mice and heterozygous littermate controls from 16 to 20 weeks of age. Affected mice showed reduced anxiety, with a decrease in the number of stretch-attend postures during the elevated plus maze (p=0.001) and an increased tendency to linger in the center of an open field (p=0.032). Water maze testing showed impaired spatial learning, with reduced preference for the target quadrant (p=0.01). In radial arm maze testing, affected mice failed to achieve above-chance performance in a win-shift working memory task (t-test relative to 50% chance: p=0.289), relative to controls (p=0.037). We found a 12.4% reduction in mean acetylcholinesterase activity (p<0.001) and no difference in choline acetyltransferase activity or acetylcholine in whole brain of affected male animals compared to controls. Cholinergic pathways are affected in adult-onset dementias, including Alzheimer disease. Our results suggest that male Sanfilippo B mice display neurobehavioral deficits at a relatively early age, and that as in adult dementias, they may display deficits in cholinergic pathways.

Beneficial effect of blood transfusion. Role of the time interval between the last transfusion and transplantation.

We analyzed the effect of blood transfusion (BT) on kidney allograft survival in 163 recipients. Transfused recipients (121) had better graft outcome than those never transfused (42), the difference being statistically significant at 3, 6, 12, and 24 months; however, the transfused group had a longer period of hemodialysis (P = 0.01). HLA antigen distribution does not bias the data. The group who had received the last BT within 3 months before grafting had a significantly better graft outcome than the nontransfused group (P less than 0.05 at 3, 6, and 24 months). They also did better (but not significantly) than the group who had been transfused more than 6 months before grafting. The group receiving two to five BTs had the highest rate of graft survival (P less than 0.05, 0.001, and 0.05 at 6, 12, and 24 months) as compared to the nontransfused. Practical suggestions for systematic BTs during hemodialysis are made.

[Cutaneous vasculitis after hepatitis B vaccination with recombinant vaccine in a renal transplant patient]. / Vascularite cutanée après vaccination contre l'hépatite virale B par vaccin recombinant chez une transplantée rénale.

BACKGROUND: Cutaneous vasculitis is a known complication of hepatitis B vaccination with recombinant vaccine. CASE REPORT: A renal transplant recipient with the HLD-DR4 susceptibility antigen developed histologically proven cutaneous vasculitis with serum antibodies after vaccination with anti-hepatitis B recombinant vaccine. The skin manifestation, evolved favorably after discontinuation of the immunization and bed rest. DISCUSSION: This case suggests that anti-hepatitis B vaccination with recombinant vaccine can produce cutaneous vasculitis in renal transplant recipients. The vaccination strategy in this population should be revisited.

Using low-field NMR to infer the physical properties of glassy oligosaccharide/water mixtures.

Low-field NMR (LF-NMR) is usually used as an analytical technique, for instance, to determine water and oil contents. For this application, no attempt is made to understand the physical origin of the data. Here we build a physical model to explain the five fit parameters of the conventional free induction decay (FID) for glassy oligosaccharide/water mixtures. The amplitudes of the signals from low-mobility and high-mobility protons correspond to the density of oligosaccharide protons and water protons, respectively. The relaxation time of the high-mobility protons is described using a statistical model for the probability that oligosaccharide hydroxyl groups form multiple hydrogen bonds. The variation of energy of the hydrogen bond is calculated from the average bond distance and the average angle contribution. Applying the model to experimental data shows that hydrogen atoms screen the water oxygen atoms when two water molecules solvate a single hydroxyl group. Furthermore, the relaxation time of the oligosaccharide protons is independent of its molecular weight and the water content. Finally, inversion of the FID using the inverse Laplace transform gives the continuous spectrum of relaxation times, which is a fingerprint of the oligosaccharide.

[Use of a Tenckhoff catheter implanted in the superior vena cava in hemodialysis]. / Utilisation du cathéter de Tenckhoff implanté dans la veine cave supérieure en hémodialyse.

For some patients in hemodialysis, repeated failure of conventional access routes requires consideration of unusual forms of access. For others, peritonitis or other problems may temporarily restrict the use of peritoneal route. We report our experience with Tenckhoff peritoneal dialysis catheter implanted into the superior vena cava through a venotomy in the right external jugular vein. The catheter was used for hemodialysis in five patients and we had no serious problems. Recirculation rate and removal rates of BUN and creatinine showed a satisfactory dialysis efficiency. While we do not recommend the procedure for routine permanent access, we believe that this technique provides a significant new choice in patients in whom conventional access methods have failed.