ABSTRACT
Scanning tunnelling spectroscopy (STS) was used to study the Luttinger liquid behaviour of the purple bronze Li(0.9)Mo(6)O(17) in the temperature range 5 K < T < 300 K. In the entire temperature range the suppression of the density of states at the Fermi energy can be fitted very well by a model describing the tunnelling into a Luttinger liquid at ambient temperature. The power-law exponent extracted from these fits reveals a significant increase above 200 K. It changes from α = 0.6 at low temperature to α = 1.0 at room temperature.
Subject(s)
Lithium Compounds/chemistry , Microscopy, Scanning Tunneling/methods , Models, Chemical , Models, Molecular , Rheology/methods , Solutions/chemistry , Computer Simulation , Phase TransitionABSTRACT
Ischemic heart disease and other complications of atherosclerosis are the usual cause of death in patients with chronic renal failure. Important factors associated with early onset of atherosclerosis in these patients are hyperhomocysteinemia, hyperfibrinogenemia, and elevated levels of lipoprotein(a) (Lp(a)). Folic acid (15 mg/d), pyridoxine (150 mg/d), and cyanocobalamin (1 mg/wk) were administered for 4 weeks in 21 patients receiving dialysis, and a simultaneous, statistically significant reduction in the concentration of homocysteine, fibrinogen, and Lp(a) was found. A positive correlation between decreasing homocysteine and fibrinogen levels was also noted. The parameters studied approached presupplementation values 6 months after vitamins were discontinued. The results suggest that vitamin supplementation has a favorable effect on risk factors of atherosclerosis in patients with renal failure and that interactions may exist between homocysteine, fibrinogen, and Lp(a).
Subject(s)
Fibrinogen/metabolism , Homocysteine/blood , Kidney Failure, Chronic/drug therapy , Lipoprotein(a)/blood , Vitamin B Complex/pharmacology , Vitamin B Complex/therapeutic use , Adult , Arteriosclerosis/blood , Arteriosclerosis/complications , Arteriosclerosis/drug therapy , Arteriosclerosis/metabolism , Cholesterol/blood , Creatinine/blood , Drug Therapy, Combination , Female , Folic Acid/pharmacology , Folic Acid/therapeutic use , Humans , Kidney Failure, Chronic/blood , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/metabolism , Male , Pyridoxine/pharmacology , Pyridoxine/therapeutic use , Renal Dialysis , Risk Factors , Triglycerides/blood , Urea/blood , Uric Acid/blood , Vitamin B 12/pharmacology , Vitamin B 12/therapeutic useABSTRACT
Lipoprotein (a) and fibrinogen admittedly are independent risk factors of coronary heart disease. Since Lp (a) has been shown to inhibit plasminogen binding to endothelial cells and to fibrin monomers, this led to the speculation that high Lp (a) levels in plasma could interfere with fibrinolysis. Therefore the aim of our work was to estimate the lipoprotein (a) and fibrinogen levels and to find correlation between lipoprotein (a) and fibrinogen levels at the men after a myocardial infarction and also at their sons. We examined 33 men of age 31-57 after a myocardial infarction and their 18 sons 4-14 years old. The control group consisted of 40 men of age 18-57 and their 19 sons 5-14 years old. The Lp (a) was determined with electroimmunodiffusion method and fibrinogen by Clauss method. The fibrinogen level in the examined group was found to be statistically significantly higher (338 mg/dl) than in the control group (313 mg/dl). There was no correlation between Lp(a) and fibrinogen concentration. In the group of sons of patients mean fibrinogen and Lp (a) levels were similar to those of the control group. However there was a negative correlation between the fibrinogen and the triglycerides concentration in sons of patients but not in the control group. The results seem to confirm the significance of fibrinogen as a risk factor for the development of the coronary heart disease.