大鼠实验性急性胰腺炎时血浆和组织脂质过氧化物的变化

本文观察了大鼠实验性急性胰腺炎时血浆和组织脂质过氧化物(LPO)的动态变化。发病后10h动物血浆LPO即见升高,而血浆淀粉酶水平则开始下降。发病10、20h心、肝、肾、肺组织LPO也有不同程度的升高。这证实了氧自由基在急性胰腺炎病理过程中起一定作用。与用血清淀粉酶水平判断急性胰腺炎的发生、发展这一传统方法相比,血浆LPO更能反映急性胰腺炎后期病变的程度及此时全身器官组织受损的情况。     

Humoral antibody response to bovine leukemia virus infection in cattle and sheep.

In this study, 345 cattle from 7 herds with a history of lymphosarcoma were tested for antibody to BLV antigens by three serological methods, namely immunodiffusion using a bovine leukemia virus glycoprotein with a molecular weight of 60,000 as antigen, and radioimmunoassay using a bovine leukemia virus glycoprotein with a molecular weight of 60,000 and a bovine leukemia virus protein with a molecular weight of 24,000 as antigen. The three tests under comparison agreed for 335 animals, 240 being negative in the three tests, and 95 being positive. Results were variable in ten cases only. Glycoprotein with a molecular weight of 60,000 antibody titers were systematically higher than were protein with a molecular weight of 24,000 antibody titers in bovine sera and milk, as well as in sera of experimentally infected sheep. In the latter case, antibodies to bovine leukemia virus antigens reached maximal values at the animal death in the tumor phase of the disease. Ratios of serum antiglycoprotein titer to milk titer varied between 4 and 117, showing that, if milk pools are to be used in surveys of bovine leukemia virus infection, use of very sensitive techniques of detection is mandatory.     

Emphysematous pyelonephritis with favourable outcome after conservative treatment

Emphysematous pyelonephritis is a necrotizing renal infection characterized by bacterial gas production in the renal and perirenal area. It is a rare infection diagnosed in diabetic patients in most cases. Emphysematous pyelonephritis is responsible for a high mortality rate. We report the case of a woman, unknown diabetic, who presented with emphysematous pyelonephritis. Early diagnosis performed by CT-scan allowed effective and conservative surgical treatment and final positive outcome.     

Antioxidant defence mechanisms: new players in the pathogenesis of non-alcoholic steatohepatitis?

This comment discusses the study by Videla and colleagues in this issue of Clinical Science in which they have analysed surgical liver biopsies from obese patients with non-alcoholic fatty liver disease and demonstrate that fatty liver is associated with a state of oxidative stress and a decreased antioxidant activity. As the disease progresses to steatohepatitis, the defect in antioxidant systems increases. Thus efficiency of antioxidant defence mechanisms, by setting the threshold at which pro-oxidants would become injurious, might represent a determining factor for disease progression from stable steatosis to steatohepatitis.     

Cerebrospinal fluid lactate and pyruvate concentrations and their ratio in children: age-related reference intervals

BACKGROUND: Lactate (L) and pyruvate (P) concentrations in cerebrospinal fluid (CSF) and the L/P ratio have diagnostic value in numerous primary and acquired disorders affecting the central nervous system, but age-related reference values are not available for children. METHODS: We analyzed CSF and blood lactate and pyruvate concentrations and their ratio in a 4-year retrospective survey of a children's hospital laboratory database. Reference intervals (10th-90th percentiles) were established from data on 197 hospitalized children. A recent regression modeling method was used to normalize and smooth values against age. The model equation of best fit was calculated for each variable. RESULTS: Slight age-related variations were shown by the model, with an increase in lactate, a decrease in pyruvate, and a resulting increase in the L/P ratio with increasing age. However, the SD did not vary with age. We defined the upper limit of the reference intervals as the 90th percentiles, which from birth to 186 months of age varied continuously from 1.78 to 1.88 mmol/L (6%), 148 to 139 micro mol/L (6%), and 16.9 to 19.2 (14%) for lactate, pyruvate, and the L/P ratio, respectively. At a threshold of 2 (in Z-score units), the sensitivity for a subgroup of inborn errors of metabolism (respiratory chain disorders) was 73%, 42%, and 31% for lactate, pyruvate, and the L/P ratio, respectively. CONCLUSIONS: In children, CSF lactate and pyruvate concentrations and their ratio appear to vary slightly with age. Average 90th percentile values of 1.8 mmol/L, 147 micro mol/L, and 17, respectively, could be used in infants up to 24 months of age. In older children, age-adjusted reference intervals should be used, especially when values are close to the 90th percentile.     

Metabolic response to a C-glucose load in human immunodeficiency virus patients before and after antiprotease therapy

Changes in glucose and fat metabolism associated with human immunodeficiency virus (HIV) infection have received attention because of the development of glucose intolerance, dyslipidemia, and lipodystrophy associated with protease inhibitor (PI) therapy. The response to ingested [13C]glucose (1.4 g/kg) was determined in 9 asymptomatic male HIV patients before and after 4.8 months of PI therapy (nelfinavir, 2,250 mg/d) compared with 9 matched seronegative HIV controls. No significant difference was observed for basal plasma glucose, insulin, and C-peptide concentrations between controls and patients before PI therapy. After 4.8 months of PI therapy, basal plasma glucose concentration was slightly, but significantly, increased (approximately 15%) compared with controls or HIV patients prior to receiving PI therapy. Over the first hour following ingestion of the glucose load, plasma glucose and insulin concentrations were higher in HIV patients than in controls, both before (approximately 15% and approximately 29%, respectively) and after (approximately 32% and approximately 43%, respectively) PI therapy. In addition, plasma C-peptide concentration was approximately 61% higher after PI therapy. The oxidation rate of fat, endogenous, and exogenous glucose was computed from the VO2 and respiratory exchange ratio corrected for protein oxidation and from 13C/12C in expired CO2. The only difference between controls and patients both before and after PI therapy was observed over the first 120 minutes following ingestion of the glucose load, when HIV patients oxidized approximately 18% more glucose and approximately 19% less fat than controls. This was not due to a larger oxidation rate of exogenous glucose, but to a larger oxidation rate of endogenous glucose (approximately 50%) in patients compared with controls. These data indicate that HIV infection is associated with minor changes in glucose metabolism, and that PI therapy with nelfinavir for 4.8 months only slightly further impairs glucose metabolism as assessed in response to a large oral glucose load. However, the larger stimulation of total and endogenous glucose oxidation and the larger reduction in fat oxidation, observed in the metabolic response to the glucose load in HIV patients, over time, could result in the accumulation of body fat and could contribute to lipodystrophy.