Effect of transplantation of embryonic anterior hypothalamic tissue from spontaneously hypertensive rats to normotensive Wistar rats on circadian rhythms of systolic arterial pressure and heart rate

The anterior hypothalamus (AH) participates in the regulation of arterial pressure. The suprachiasmatic nuclei (SCN) of the AH are a major circadian oscillator necessary for the generation and/or the entrainment of circadian rhythms. Circadian rhythms of systolic arterial pressure (SAP) and heart rate (HR) were investigated in spontaneously hypertensive rats (SHR) and in normotensive Wistar rats (NWI) with intact SCN, grafted with SHR embryonic AH tissue containing the SCN. Prominent circadian rhythms for SAP and HR in both NWI and SHR with acrophases during dark were found. The elevation of the MESOR (midline-estimated statistic of rhythm) of the SAP in normotensive rats grafted with AH embryonic tissue obtained from SHR was accompanied by disappearance of the circadian rhythm of SAP. This result suggests an interaction between the grafted tissue containing the SCN on the one hand, and the host SCN on the other hand. Our data ascribe a role for the SCN in the entrainment of the circadian rhythm of arterial pressure. The circadian rhythm of HR was not eliminated by the SCN graft in spite of the amplitude decrease and the phase delay observed. It seems that the entrainment of the circadian rhythm of HR is probably not crucially dependent on the SCN in rats. The circadian rhythms of SAP and HR in rats were differently affected by the grafts, thus suggesting a multioscillatory system for circadian regulation in rats.     

Intestinal transplantation in children under FK 506 immunosuppression

Intestinal transplantation, solitary (n = 3) or in combination with the liver (n = 7), was performed in 10 pediatric patients with intestinal failure. The liver was only replaced if there was liver failure and portal hypertension. Immunosuppression was based on FK 506. Two patients died, one of graft-versus-host disease and one of lymphoproliferative disease. One patient as still in the intensive care unit 1 month posttransplantation due to perioperative complications. The function of the intestinal grafts in the remaining patients is normal. All nutrition and medications including immunosuppression are being administered enterally. This series indicates that small bowel transplantation, alone or in combination with the liver, is feasible in pediatric patients.     

A process for the introduction of elemental sulphur into high analysis phosphate fertilisers

A method for producing and incorporating fine elemental sulphur into high analysis fertilisers based on phosphoric acid is described. Molten sulphur is added to phosphoric acid under high shear conditions to produce a slurry containing fine sulphur. The slurry is subsequently used to acidulate phosphate rock and the resultant high analysis fertiliser contains sulphur which is sufficiently fine to ensure reasonably rapid oxidation to sulphate by soil micro-organisms. A small pilot plant has been used to produce a triple superphosphate containing 15% elemental sulphur which has a particle size distribution of: 95% < 0.5 mm, 76% < 0.25 mm and 57% < 0.15 mm.     

Creatine supplementation enhances intermittent work performance

The metabolism of theophylline (TP) (540 mg per os) was determined by measuring plasma and saliva concentrations of TP and its metabolites, 0-24 h after loading, and urinary excretion 0-48 h after loading. TP and its five metabolites were separated and quantified by combining high-performance liquid chromatography and capillary electrophoresis. In addition to TP, 1,3-U, 3-X and 1-U were consistently found in plasma and saliva. The area under the plasma concentration-time curve (AUC) showed that TP accounted for 91 +/- 4% (mean +/- SD) of the total AUC in plasma with 1,3-U accounting for 3.1 +/- 1.4%, 3-X for 3.4 +/- 1.8% and 1-U for 2.5 +/- 1.5%. The urine analyses showed that unchanged TP accounted for 19 +/- 5% of total excretion, the remainder being 1, 3-dimethyluric acid (1,3-U, 41 +/- 6%), 1-methylxanthine (1-X, 2 +/- 0.8%), 1-methyluric acid (1-U, 26 +/- 6%), 3-methylxanthine (3-X, 11 +/- 3%) and 3-methyluric acid (3-U, 1 +/- 0.3%). Highest excretion rates were observed for 1,3-U (70 +/- 29 mumol/h), 1-U (40 +/- 26 mumol/h) and 3-X (20 +/- 15 mumol/h) 6-9 h after TP ingestion suggesting the high excretion of 1,3-U, 1-U and 3-X by the kidneys. The highest excretion rate of TP (50 +/- 8 mumol/h) occurring at 0-6 h after the load and rapidly declining thereafter, indicated the lower excretion of TP compared with its metabolites. N3-demethylation of TP accounted for 34 +/- 6% of the urinary metabolites, N1-demethylation of TP for 15 +/- 3% and C8-oxidation of TP for 51 +/- 9%. C8-oxidation of 1-X and 3-X was 93 +/- 4%, and 9 +/- 4%, respectively, of the excreted amount of monomethylxanthine plus formed monomethylurate. Since the extent of all metabolic reactions remained constant during the load, it is suggested that TP is metabolized by hepatic reactions that occurred simultaneously and not sequentially.     

Posterior interosseous flap and its variations for coverage of hand wounds

Damage of large arteries is a major contributory factor to the high pulse pressure observed in patients with end-stage renal disease. Whether incremental modulus of elasticity (Einc), a classic marker of arterial stiffness, can predict cardiovascular mortality has never been investigated. A cohort of 79 patients with end-stage renal disease undergoing hemodialysis was studied between September 1995 and January 1998. Mean age at entry was 58+/-15 years. The duration of follow-up was 25+/-7 months, during which 10 cardiovascular and 8 noncardiovascular fatal events occurred. At entry, carotid Einc was calculated from measurements of diameter, thickness (echo-tracking technique), and pulse pressure (tonometry). Based on Cox analyses, 2 dominant factors emerged as predictors of all-cause and cardiovascular mortality: increased Einc and decreased diastolic blood pressure. Lipid abnormalities and the presence of previous cardiovascular events interfered to a smaller extent. After adjustment for confounding variables, the odds ratio for Einc >/=1 kPa-3 was 9.2 (95% confidence interval, 2.4 to 35.0) for all-cause mortality. These results provide the first direct evidence that in patients with end-stage renal disease undergoing hemodialysis, arterial alterations, as determined from carotid Einc, are strong independent predictors of all-cause and cardiovascular mortality.