The effects of anesthesia on the biodistribution of drugs in rats: a carboplatin study

PURPOSE: Anesthetics can alter the biodistribution profile of drugs and, consequently, the regional pharmacokinetics of antineoplastic drugs at the tumor site. The effect of coadministered anesthetics on the biodistribution profile of carboplatin was studied in rats. METHODS: Female Wistar rats were used to compare the effects of ketamine/xylazine, thiopental and pentobarbital on the biodistribution of 30 mg/kg radiolabelled 195mPt-carboplatin administered intravenously, with conscious rats as the control group. Blood and urine samples were collected between 5 and 120 min. RESULTS: The percentage values of the injected dose of platinum per ml (%ID/ml) in plasma at the final time-point were respectively, 0.557%, 0.156%, 0.115% and 0.086%, in pentobarbital-, ketamine/xylazine- and thiopental-injected rats, and in conscious animals. Following the same sequence of groups, the %ID/ml values of platinum in the cumulative urine were 0.001%, 0.619%, 0.184% and 0.118%, respectively. Urine output varied from very little in the pentobarbital group, to several milliliters in the other groups. CONCLUSIONS: There was an increase of almost 100-fold in total platinum uptake in the kidneys, cerebrum and cerebellum of rats receiving pentobarbital over the uptake in the control rats, whereas the biodistribution profile of the thiopental group had the least variance. These results demonstrate the importance of anesthetic selection in animal pharmacokinetic studies, as it influences the biodistribution and pharmacokinetic profile of the drug being studied.     

Fallibility of plasma urea and creatinine as indices of renal function in diarrhoeic calves treated with conventional or nutritional oral rehydration solutions

The prevalence and severity of gingival overgrowth in organ-transplant patients medicated with cyclosporin are greater in patients concomitantly medicated with nifedipine; however, no relationship between the gingival overgrowth and any of the nifedipine pharmacological variables has been demonstrated. The study examined the effect of five nifedipine pharmacological variables (nifedipine dosage, plasma concentration and gingival crevicular fluid concentration, M1 metabolite plasma concentration and the nifedipine: M1 ratio). The effect of the nifedipine variables on the gingival overgrowth score were examined using univariate and multivariate regression analysis. Adjustment for the effect of other risk factors was made by adding the distribution of each of the nifedipine variables in turn to a stepwise regression model containing previously identified risk factors for this condition. Despite the high levels of nifedipine sequestered in the GCF, only the plasma concentration of nifedipine was identified as a risk factor for the severity of gingival overgrowth in these patients (P = 0.01) once adjusted for other known risk factors (R2 for the model = 55%).     

Beta-1-integrin expression in adult acute lymphoblastic leukemia: possible relationship with the stem cell antigen CD34

In the hemopoietic system, interactions between stem cells and components of the bone marrow microenvironment play a pivotal role in blood cell proliferation and differentiation. Among the adhesion molecules, the integrins of the beta 1-subfamily are known to direct cell-cell and cell-matrix interactions and evidence has been provided that CD34-positive stem cells bind either to the bone marrow stroma or to the extracellular matrix proteins through the beta 1-integrins. It seems that changes in their expression pattern or signalling function are likely to reflect disturbances at the hemopoietic bone marrow microenvironmental level. Any alteration of their biological functions makes them attractive candidates for playing decisive roles in the leukemic processes. In this view, beta 1-integrins have been recognized to mediate those cellular interactions and migrations that are important in the biology of leukemia. In this paper we review some aspects of the role played by beta 1-integrins, especially VLA-4 and VLA-5, in adult acute lymphoblastic leukemia in relation with the expression rate of the stem cell antigen CD34.     

Chemical Ecology of the host searching behavior in an Egg Parasitoid: are Common Chemical Cues exploited to locate hosts in Taxonomically Distant Plant Species?

Parasitoids are known to exploit volatile cues emitted by plants after herbivore attack to locate their hosts. Feeding and oviposition of a polyphagous herbivore can induce the emission of odor blends that differ among distant plant species, and parasitoids have evolved an incredible ability to discriminate them and locate their hosts relying on olfactive cues. We evaluated the host searching behavior of the egg parasitoid Cosmocomoidea annulicornis (Ogloblin) (Hymenoptera: Mymaridae) in response to odors emitted by two taxonomically distant host plants, citrus and Johnson grass, after infestation by the sharpshooter Tapajosa rubromarginata (Signoret) (Hemiptera: Cicadellidae), vector of Citrus Variegated Chlorosis. Olfactory response of female parasitoids toward plants with no herbivore damage and plants with feeding damage, oviposition damage, and parasitized eggs was tested in a Y-tube olfactometer. In addition, volatiles released by the two host plant species constitutively and under herbivore attack were characterized. Females of C. annulicornis were able to detect and significantly preferred plants with host eggs, irrespectively of plant species. However, wasps were unable to discriminate between plants with healthy eggs and those with eggs previously parasitized by conspecifics. Analysis of plant volatiles induced after sharpshooter attack showed only two common volatiles between the two plant species, indole and β-caryophyllene. Our results suggest that this parasitoid wasp uses common chemical cues released by many different plants after herbivory at long range and, once on the plant, other more specific chemical cues could trigger the final decision to oviposit.

     

Fraud identification in industrial meat products by multiplex PCR assay

The identification of animal species used in industrial meat products is very important in respect to economic considerations because European Union, which has implemented a set of very strict procedures to correctly label food. In this paper we present conserved region from mitochondrial 12S rRNA and 16S rRNA genes are powerful region for evaluate the presence of fraudulently added meat in compound food by multiplex polymerase chain reaction assay for the identification of most species (ruminant, poultry and porcine). For each food sources (ground meat, sausages and cold cut) 10 samples were collected and DNA extracted successfully. The results demonstrated that none of the samples were contaminated with porcine residuals, but 40% of sausages samples and 30% of cold cut samples were contaminated with poultry residuals. Also the ground meat samples were not contaminated with poultry residuals.