Patterns of temperature adaptation in proteins from Methanococcus and Bacillus.

It has long been known that amino acid substitutions in proteins of organisms living at moderate and high temperatures (mesophiles and thermophiles, respectively) are not all symmetrical; for example, more aligned sites have lysine in mesophiles and arginine in thermophiles than have the opposite pattern. This is generally taken to indicate that certain amino acids are favored over others by selection at different temperatures. Previous comparisons of protein sequences from mesophiles and thermophiles have used relatively small numbers of sequences from a diverse array of species, meaning that only the most common amino acid substitutions could be examined and any taxon-specific patterns would be obscured. Here, we compare a large number of proteins between mesophiles and thermophiles in the archaeal genus Methanococcus and the bacterial genus Bacillus. Each genus exhibits dramatically asymmetrical substitution patterns for many pairs of amino acids. There are several pairs of amino acids for which one amino acid is favored in thermophilic Bacillus and the other is favored in thermophilic Methanococcus; this appears to result from the higher G + C content of the DNA of thermophilic Bacillus, a complication not seen in Methanococcus.

The association between rhabdomyolysis and acute renal failure in patients undergoing cardiopulmonary bypass.

OBJECTIVE: The authors describe 9 cases of rhabdomyolytic acute renal failure (ARF) as a complication of cardiopulmonary bypass. EXPERIMENTAL DESIGN: Retrospective research between June 1992 and March 1994. SETTING: Department of Cardiac Surgery. PATIENTS: 931 consecutive patients undergoing major cardiac surgery. INTERVENTIONS: Patients affected by rhabdomyolytic ARF were treated with pharmacological therapy and/or plasmapheresis/continuous arteriovenous hemofiltration. In seven patients indirect cannulation of the femoral artery was used. MEASURES: Incidence, risk factors of syndrome results obtained with pharmacological treatment, CAVH and plasmapheresis were evaluated. Statistical analysis was performed with ANOVA, Tukey Kramer test and chi2 test (p<0.05 as significant). RESULTS: The syndrome occurred in 0.96% (9/931 patients) of the total cases; 11.3% (6/53 -p<0.0000) in patients undergoing a direct femoral artery cannulation for cardiopulmonary bypass and 9.5% (2/21, p<0.01) in patients in which the aortic balloon pump was used. Six patients develop acute anuric renal failure and underwent plasma exchange and hemodialysis (1 case) or CAVH (5 cases); 3 patients underwent early medical treatment and developed developed acute renal failure (ARF) with preserved diuresis. Early medical therapy appeared to prevent the evolution towards anuric ARF. The indirect cannulation of the femoral artery does not seem to produce a rhabdomyolytic ARF syndrome. In patients with direct femoral artery cannulation risk factors appear to be: arteriopathy (p<0.001), prolonged extra corporeal circulation (p<0.001), low cardiac output syndrome (p<0.001), continuous i.v. infusion of epinephrine (p<0.0001). CONCLUSIONS: Rhabdomyolytic acute renal failure is a severe complication, early identification of patients ¿at risk¿ is most important. The preventive measures and the therapy adopted proved efficient.

Effects of the treatment with matrix on elderly people with chronic articular degeneration.

Clinical trials have been conducted to evaluate the effectiveness of Matrix in osteoarthritis, mainly as regards the advantages offered by its physiological mechanism of action. The experiment, lasting 6 months, was performed on two hundred patients in four different Hospital Departments and one University Center. The results showed a considerable improvement both in pain and in mobility. No relevant side effects were found; only 3% of patients, with oral administration, noticed slight nausea and found it necessary to interrupt treatment.