Marked increase of asymmetric dimethylarginine in patients with incipient primary chronic renal disease.

In patients with uremia, increased blood concentrations of the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA) have been linked to the severity of atherosclerosis and to excess cardiovascular mortality. The ADMA levels and several traditional cardiovascular risk factors were assessed in 44 untreated nonsmoking patients with confirmed primary chronic renal disease at different stages of renal disease. True GFR was assessed by means of the inulin-clearance technique. For comparison, nonsmoking subjects matched with respect to age, gender, and body-mass index were examined. Mean plasma ADMA concentration was markedly higher (P < 0.0001) in all patients combined (4.2 +/- 0.9 micromol/L) than in control subjects (n = 16; age 45 +/- 10 yr; serum creatinine 1.0 +/- 0.1 mg/dl; ADMA 1.4 +/- 0.7 micromol/L). However, mean ADMA levels were similar in patients with normal renal function (n = 16; age 41 +/- 9 yr; serum creatinine 1.1 +/- 0.1 mg/dl; GFR 120 +/- 14 ml x min(-1) x 1.73 m2; ADMA 4.0 +/- 0.7 micromol/L), in patients with moderate renal failure (n = 15; 47 +/- 7 yr; 1.8 +/- 0.3 mg/dl; 65 +/- 10 ml x min(-1) x 1.73 m2; 3.8 +/- 0.6 micromol/L) and in patients with advanced renal failure (n = 13; 46 +/- 9 yr; 4.2 +/- 0.9 mg/dl; 25 +/- 4 ml x min(-1) x 1.73 m2; 4.7 +/- 1.2 micromol/L). Furthermore, ADMA levels were increased to the same extent in normotensive (n = 17; 4.0 +/- 0.8 micromol/L) and in hypertensive (n = 27; 4.2 +/- 0.9 micromol/L) patients. In contrast to ADMA, mean total plasma homocysteine concentration were similar in control subjects (10.6 +/- 2.9 micromol/L) and in patients with normal GFR (11.0 +/- 2.9 micromol/L), but were significantly higher in patients with moderate renal failure (17.7 +/- 4.1 micromol/L) and particularly in patients with advanced renal failure (28.2 +/- 10.6 micromol/L). Finally, mean total serum cholesterol concentrations were comparable in the control group and in the three groups of patients with renal disease. In contrast to several traditional cardiovascular risk factors, markedly increased blood concentrations of ADMA, a putative biochemical marker of atherosclerosis, are present even in nonsmoking patients without diabetes with incipient primary renal disease. Thus, the early increase of ADMA levels may be of relevance for the excess cardiovascular morbidity and mortality due to arterio- and atherosclerotic complications in patients with renal disease.     

Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients

High serum fluoride (F-) in patients with chronic renal failure (CRF) and end-stage renal disease (ESRD) is associated with risk of renal osteodystrophy and other bone changes. This study was done to determine F- in normal healthy controls and patients with ESRD on haemodialysis (HD) or peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females) and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l) of F- content in drinking water. Control subjects showed a mean serum F- concentration of 1.08 +/- 0.350 microM/l. Males in control group showed slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F- concentration did not correlate significantly with age and sex among control subjects, whereas such correlation was observed in patients with ESRD on dialysis. Mean serum F- concentration was significantly higher in patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal controls. When grouped according to sex, the mean serum F- concentration in males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped according to age, it was observed that F- concentration was significantly higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated with age and sex, being higher in males and above 20 years. Despite appreciable clearance of F- (39-90%) across the peritoneum, patients on CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs 2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their serum F- concentration above 3.0 microM/l, posing the risk of renal osteodystrophy.      

Drug mixture which improves survival of ischemic rabbit epigastric skin flaps

The chief aim of this study was to maximize flap survival by counteracting the pathophysiological changes occurring during ischemia-reperfusion. Rabbit epigastric skin flaps given 21 hours of ischemia were infused intra-arterially with selected drugs at the start of reperfusion. Compared with control infused ischemic flaps, which had a 33% survival rate on day 7 post-ischemia, significant improvement was found with vasodilators nitrendipine (61%) and prostacyclin (65%) and the thrombolytic agent urokinase (65%); marginal improvement with the free radical scavenger desferrioxamine (53%); but no change with streptokinase (44%), heparin (21%), and ATP-MgCl₂ (35%). A drug mixture comprising all of these agents except streptokinase and urokinase produced 87% survival, suggesting an additive effect. Biochemical assays on skin homogenates and blood implicated oxygen free radicals, neutrophil infiltration, and thromboxane in flap failure. These results imply that multiple factors are responsible for ischemic flap failure and that a mixture of drugs needs to be infused to counteract all of the detrimental changes. © 1994 Wiley-Liss, Inc.     

Antigenic and allergenic analysis of psyllium seed components.

The outer portions (husk) of psyllium seeds are a concentrated source of natural fiber used in some bulk-fiber laxatives and cereals. They are known to elicit respiratory allergic reactions after inhalation or ingestion among sensitized individuals. Antigenic and allergenic characterization of three psyllium-seed fractions (husk, endosperm, and embryo) was conducted with crossed immunoelectrophoresis (CIE), crossed radioimmunoelectrophoresis, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis to determine the source of psyllium allergenicity. Homologous CIE demonstrated psyllium endosperm and embryo extracts contained seven and four antigens, respectively. Husk extracts were too gelatinous to react by CIE. However, heterologous CIE profiles of endosperm or embryo extracts, reacted with antihusk antibodies, resulted in antigen-antibody precipitin peaks that matched the heavy staining precipitin lines of homologous reactions for endosperm and embryo, respectively. These results indicated that commercial-grade husk, endosperm, and embryo contained similar antigens. Extracts of all three seed components contained antigens that bound IgE antibodies in the sera of 11 psyllium RAST-positive individuals, as determined by crossed radioimmunoelectrophoresis. The few prominent husk protein/peptide bands resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were common in either embryo or endosperm. Immunoblots revealed common IgE reactive bands in all three seed fractions. Microscopic examination of the powdered commercial-grade psyllium (95% pure) revealed it contained endosperm and embryo particles. These immunologic, biochemical, and microscopic findings suggest that other contaminating seed components are primarily responsible for the allergenicity of commercial-grade psyllium-husk powder rather than the husk itself.     

新疆家畜蠕形蚤病病原研究

本文详细介绍了在新疆发现的花蠕形蚤、叶氏蠕形蚤、北山羊蠕形蚤、羊长喙蚤和狍长喙蚤的形态学特点、地理分布和某些生物学特性。     

Age estimation in biopsy specimens of dentin

Determination of age at death on the basis of aspartic acid racemization in dentin is one of the most reproducible and accurate methods. In Germany, age estimation by this method has so far generally not been applied to living persons, since the extraction of a tooth exclusively for age estimation when it is not medically indicated is regarded as ethically and legally problematic. The development of a biopsy technique applicable to dentin took place against this background. Testing the technique and analysis of dentinal biopsy specimens revealed that the biopsy technique is a low-risk procedure that causes only minor discomfort to the affected person. It is readily practicable and facilitates standardized specimen removal. The relationship between the extent of aspartic acid racemization in dentinal biopsy specimens and age is very close, facilitating age estimation. A prerequisite for accurate results is the performance of biopsies under strictly standardized conditions. If this is guaranteed, age determination on the basis of aspartic acid racemization in dentinal biopsy specimens appears to be superior in precision to most other methods in living persons and can be used for all age groups.     

Excess of DD homozygotes in haemodialysed patients with type II diabetes. The Diabetic Nephropathy Study Group

The role of the insertion/deletion polymorphism of the angiotensin- converting enzyme (ACE) gene in the genesis of diabetic nephropathy has been controversial. It has recently been proposed that progression occurs more rapidly in individuals with diabetic and non-diabetic renal disease who are homozygous for the D allele. We studied 658 patients with type II diabetes, 347 without diabetic nephropathy and 311 with various stages of diabetic nephropathy, and determined the I/D polymorphism of the ACE gene. Patients at the extremes of renal risk, i.e. normotensive patients without antihypertensive treatment and without nephropathy (n = 144), vs patients on dialysis (n = 61), differed with respect to genotype (DD 36.8% vs 57.4%; P = 0.007) and allele frequencies (D 0.59 vs 0.76; P < 0.001). In contrast, patients with and without presumed nephropathy as assessed by albuminuria did not differ with respect to DD genotype. In conclusion, in this study, which was limited by sample size, patients with the highest renal risk more frequently had the DD genotype. This would be compatible with a greater risk of (or rate of) progression to end-stage renal failure.