Experimental pyeloureterectomy and calyceal neck transection with autotransplantation and bladder advancement

OBJECTIVE: To determine whether Dexon mesh, closely applied to the kidney, provides purchase for sutures to permit bladder/parenchymal apposition on autotransplantation and that, if this line of apposition were some distance from but surrounding renal papillae, urothelium would proliferate to cover exposed parenchyma to form a widely patent lumen; this should facilitate removal of the whole of an upper tract collecting system, retaining renal parenchyma alone. MATERIALS AND METHODS: To test this possibility and explore the practicability of the concept, nine dogs underwent bilateral nephrectomy followed by unilateral autotransplantation: the other kidney was discarded. Because the canine renal pelvis is intrarenal, the ureter was stretched maximally before passing fine scissors into the renal hilum to transect the collecting system as close to the kidney as possible in six of the nine dogs. In the remaining three dogs, partial nephrectomy was performed with division of the calyceal necks under vision. Thinned bladder wall was sutured to Dexon mesh some distance from the collecting tubules; omentum was applied to the suture line. RESULTS: Three dogs were killed prematurely at < 2 weeks because of perioperative complications. Four were killed at 2, 4, 5 and 8 weeks and two at 12 months. Dexon mesh proved to be an effective anchoring fabric, providing close apposition of bladder wall and parenchyma. There was no adhesion of the kidney to peritoneal contents. Urothelial proliferation to cover exposed parenchyma occurred early and by 12 months, a thin stroma was interposed between parenchyma and epithelium. The kidney was preserved in all but one removed electively, this dog having both cystitis and pyelonephritis at 12 months. CONCLUSIONS: This study showed that autotransplantation of a kidney after removal of its collecting system and advancement of thinned bladder wall to renal parenchyma is practicable, with regenerated urothelium bridging the deficiency by covering exposed parenchyma, to create a widely patent lumen.     

Human herpesvirus-6 infection in liver transplant recipients: documentation of pathogenicity

In the posterior partially edentulous jaw, implants may be used to supplement existing natural dentition. Frequently, the maxillary sinuses and the mandibular nerve preclude the fabrication of freestanding implant-retained prostheses. However, if an implant and a natural abutment are combined, a fixed prosthesis can be fabricated, restoring the arch into the premolar area. The histories of three patients with attachments connecting implant-retained ceramotitanium crowns with crowns on natural abutments are described. A design for a rigid custom-made attachment for the Br?nemark system, using standard components with a machine-duplication, spark-erosion technique, is suggested.     

Clinical and economic analysis of allogeneic peripheral blood progenitor cell transplants: a Canadian perspective

Allogeneic peripheral blood progenitor cell (PBPC) transplants are an alternative to BMT, although G-CSF mobilization dose, timing of pheresis and risk of GVHD are not well defined. We compared harvest characteristics, donor and recipient outcomes and costs of two PBPC transplant strategies with historical controls who received BMT. Twenty donors mobilized with four daily s.c. G-CSF doses (5 microg/kg/day) (group 1) and 20 mobilized with 10 microg/kg/day G-CSF (group 2) were compared with 20 BM controls (group 3). G-CSF and phereses were well tolerated. Four of 40 PBPC donors required femoral catheter placement. At least 2.5 x 10(6) CD34+/kg recipient weight were collected with two phereses in 19/20 donors (group 1) and 18/20 donors (group 2). Time to neutrophil (18 vs 20 vs 22 days, P = 0.02) and platelet (21 vs 24 vs 27 days, P = 0.005) engraftment was shorter in the PBPC groups (group 2 vs group 1 vs group 3) but secondary engraftment outcomes were not different. The incidence of grade 2-4 aGVHD was higher in the low-dose G-CSF group (group 1) but there was no difference in cGVHD, 100-day or 1-year survival. The mean PBPC transplant cost (group 1) at first hospital discharge was less than BM (group 3) ($34,643 vs $37,354) but the mean overall cost for both groups was similar at 100 days ($46,334 vs $46,083). Allogeneic PBPC transplant with short course, low-dose G-CSF mobilization is safe, feasible and cost equivalent to allogeneic BMT.     

澳洲西花蓟马及番茄病毒性萎蔫病

西花蓟马（Franklienella occidentalis）是传播番茄、马铃薯、芦笋及辣椒病毒性萎蔫病的最主要的害虫之一。西花蓟马喜食辣椒、黄瓜和豆类作物的果实。其嚼食叶片和果实后,留下疤痕或使其畸形,尤其是幼苗和鲜嫩的组织更容易受其侵害。     

CHEMICAL DEGRADATION OF TRI-n-BUTYL PHOSPHATE/DILUENT SOLVENTS TM USED IN CANDU THORIUM FUELS REPROCESSING DEVELOPMENT

At the Whiteshell Nuclear Research Establishment, the solvent used In the flowsheet examined for reprocessing thorium fuels is tri-n-butyl phosphate (TBP)in a mixture of aromatic (diethyl benzene, DEB)and aliphatic (Isopar M, supplied by Esso Chemical Canada Limited7rpar;diluents. Degradation studies described in this report have focused on the effect of exposure of this solvent to nitric acid. A comparative study of the nitric acid degradation of this solvent, with binary mixtures of TBP/lsopar M and TBP/DEB solvents, as well as each of the individual solvent components is described. The behavior of the major degradation products in washes with NaOH, H₂o and HNO₃, and the metal retention properties of the degraded systems are also examined

Zirconium-retaining species were observed in. the nitric acid degraded TBP mixed solvents, but they were not detectable when each of the solvent components was individually degraded. These species appear to be identical to those formed by radiolytic degradation. A reaction mechanism Is proposed to account for their formation.     

The herpes simplex virus type 1 helicase-primase. Analysis of helicase activity

The rate of unwinding of duplex DNA by the herpes simplex virus type 1 (HSV-1)-encoded helicase-primase (primosome) was determined by measuring the rate of appearance of single strands from a circular duplex DNA containing a 40-nucleotide 5' single-stranded tail, i.e. a preformed replication fork, in the presence of the HSV-1 single strand DNA-binding protein, infected cell protein 8 (ICP8). With this substrate, the rate at low ionic strength was highly sensitive to Mg2+ concentration. The Mg2+ dependence was a reflection of both the requirement for ICP8 for helicase activity and the ability of ICP8 to reverse the helicase reaction as a consequence of its capacity to anneal homologous single strands at Mg2+ concentrations in excess of 3 mM. The rate of unwinding of duplex DNA by the HSV-1 primosome was also determined indirectly by measuring the rate of leading strand synthesis with a preformed replication fork as template in the presence of the T7 DNA polymerase. The value of 60-65 base pairs unwound/s by both methods is consistent with the rate of 50 base pairs/s estimated for the rate of fork movement in vivo during replication of pseudorabies virus, another herpesvirus. Interaction with the helicase-primase did not increase its helicase activity.     

Information from time-varying vibrotactile stimuli

Experiments have been carried out to investigate the information transfer available via a single vibrator on the fingertip. In a first experiment, for stimuli with durations 80 to 320 ms, discrimination of a one-octave step change in frequency at the halfway point was investigated. Results were similar for three stimulus types--sinewave, monophasic pulse and tetraphasic pulse--suggesting temporal cues are more important than spectral cues in this task. In a second experiment, subjects were required to perceive changes in a sequence of stimulus elements. A presentation rate of 6.25 elements s-1 was found to give better results than a rate of 12.5 elements s-1. In the former case, the potential information transfer per element was estimated to be approximately 1.0 bits, corresponding to an information transfer rate of around 6 bits s-1. Implications for the design of a tactile aid to lipreading are discussed.     

Study of sialated neoglycoconjugates by surface enhanced Raman scattering spectroscopy

Neoglycoconjugates based on polyacrylamide and sialic acid with N-acetylneuraminic acid or sialooligosaccharides as side chains were studied by surface-enhanced Raman scattering (SERS) spectroscopy. It had previously been found that these polymers can effectively inhibit influenza virus adhesion. This study revealed the possibility to evaluate, based on the intensity of SERS signals, the overall availability for interaction and the conformational freedom of sialic acid residues in glycoconjugates. The dependence of these two factors on the structure and density of sialylated side chains was studied. The uniformity of distribution of sialylated side chains in conjugates was shown. Comparison of the results of the SERS spectroscopic study of the conjugates and the data on their inhibitory effect on the adhesion of specific strains of influenza virus allowed the identification of the conjugates for which the availability and conformational freedom of sialic acid are the main factors determining their inhibitory properties. A conclusion was also reached about the predominance of one of the mechanisms (competitive inhibition or steric stabilization) in the inhibitory properties of the specific conjugates.