How robust are our methods of detecting impaired glomerular filtration rate in the intensive care unit?

Background: Serum creatinine is not a sensitive marker to assess early loss of renal function in acute kidney injury. Timed creatinine clearance and several formula used to predict glomreular filtration rate have not been validated.     

麻风菌重组蛋白的抗原性分析

目的以ND-O-BSA、LID-1麻风菌特异抗原为参照,评价各类受检者对7种麻风菌新抗原的血清学反应性,从而筛选出可应用于麻风病诊断的抗原。方法 应用ND-O-BSA、LID-1、ML0098ss、ML0840、ML1632ss、ML2028、ML2044、ML2055ss和46f等9种合成或重组抗原建立ELISA方法,分别检测多菌型麻风病(Multibacillaryleprosy,MB)和少菌型麻风病(Paucibacillary leprosy,PB)患者以及来自非流行区、麻风病轻度和重度流行区的健康人血清中的相应抗体。结果 ELISA显示7种新抗原中ML0840与ND-O-BSA、LID-1抗原敏感性、特异性和准确性相近,在对PB患者的检测上,其准确性更显优势,高达72%。46f、ML0098ss、ML2028对MB患者的敏感性依次为86%、79%和76%,但对PB患者的检测只有ML0098ss敏感性达到55%。ML1632ss、ML2044、ML2055ss 3种抗原无论对MB还是PB患者的敏感性和特异性均较差。结论 7种麻风菌重组蛋白质均具有不同程度的抗原性,ML0840与LID-1、ND-O-BSA是目前有应用潜力的抗原,但需在血清学监测中证实其早期诊断麻风病的价值。     

50-kHz calls in rats: effects of MDMA and the 5-HT(1A) receptor agonist 8-OH-DPAT

In recent years, 50-kHz ultrasonic vocalizations of laboratory rats have become increasingly important behavioral measures in research on emotion and motivation, since these calls may help to study appetitive subjective states, for example in relation to addiction. Among others, 50-kHz calls occur when rats experience or expect rewards, including drugs of abuse, and it is assumed that these calls depend on dopamine function, especially in the meso-limbic system. One established means to induce 50-kHz calls is to challenge rats with d-amphetamine, a psychomotor stimulant, which acts largely by boosting dopamine and noradrenaline function in the brain. In a 1st experiment, we studied whether another psycho-stimulatory amphetamine, namely the derivative 3,4-methylene-dioxymethamphetamine (MDMA, Ecstasy), could also enhance 50-kHz calls by using an activity box and testing conditions, which had previously been found to be appropriate in case of d-amphetamine. In support of previous work, we found that MDMA (2.5, 5, 10 mg/kg, ip) dose-dependently increased locomotion and center time, together with decreases in rearing activity, but the drug did not elicit 50-kHz calls. Assuming that this lack of effect is due to the drug's substantial pro-serotonergic effects in the brain, which may inhibit 50-kHz calls, we performed a 2nd experiment where we tested the serotonin 5-HT_1A receptor agonist 8-hydroxy-2-tetralin (8-OH-DPAT; 0.05, 0.5, 2.5 mg/kg, ip). This drug dose-dependently stimulates serotonin autoreceptors and heteroreceptors, can act in a psycho-stimulatory way and can enhance dopamine function. In the activity box, 8-OH-DPAT increased locomotor activity (0.5, 2.5 mg/kg) and decreased rearing (2.5 mg/kg); that is, the drug seemed to share some psycho-stimulatory effects with MDMA. Unlike MDMA, 8-OH-DPAT enhanced 50-kHz calls in a dose-dependent way, namely only with the 0.5 mg/kg dose. These results are discussed with respect to their possible neurochemical mechanisms, especially on 5-HT and dopamine in the brain.     

Effects of Verbascoside-Based Diet on Blood and Plasma Constituents of Rabbits

Objective: Oxidative stress brought on by free radicals can lead to an increased risk of some chronic pathologies. Antioxidants can scavenge free radicals by turning them into nonradical and nontoxic metabolites. The purpose of this study is to investigate the effect of a phenylpropanoid glycosides–based prolonged diet on blood constituents in animals.

Methods: Tests were carried out on healthy New Zealand white rabbits and the following parameters were evaluated at baseline and after 90 days’ follow-up: plasma triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, aspartate transaminase, alanine aminotransferase, bilirubin, the reactive oxygen metabolites, thiobarbituric acid–reactive substances, vitamin A, and vitamin E. The same parameters were analyzed in an age- and sex-matched animal control group.

Results: We first defined the concept of average rate and then used it to calculate, by experimental data fitting, the formation or destruction rate of some blood or plasma constituents as a function of the daily dose. The results indicate that the effects can be categorized into 2 classes. The first includes the effects that produce monotonously continuous changes with daily dose, and the second includes those that exhibit a saturating trend.

Conclusions: The experimental results suggest that high doses of verbascoside can potentially cause adverse effects through prooxidative effects. Risk is increased by the use of pharmacological doses of polyphenols in prevention, treatment, and as dietary supplements.