Reduction of the prenatal hypoxic-ischemic brain edema with noscapine

Cytotoxic free radicals and release of several neurotransmitters such as bradykinin contribute to the pathogenesis of hypoxic-ischemic brain damage. We have studied the efficacy of noscapine, an opium alkaloid and a bradykinin antagonist, in reducing post-hypoxic-ischemic damage in developing brain of 7-d-old rat pups. Hypoxic-ischemic injury to the right cerebral hemisphere was produced by legation of the right common carotid artery followed by 3 h of hypoxia with 8% oxygen. Thirty to 45 min before hypoxia the rat pups received noscapine (dose = 0.5-2 mg/kg) or saline. Pups were scarified at 24 h post recovery for the assessment of cerebral damage by histological methods. Our results showed that noscapine was an effective agent in reducing the extent of brain injury after hypoxic-ischemic insult to neonatal rats. Therefore, it is concluded that noscapine may be a useful drug in the managements of patients after stroke.     

Advances in immunoproteomics for serological characterization of microbial antigens

We propose a multi-dimensional strategy, associating immunodetection to a protein fractionating two-dimensional liquid chromatography tool, for serological characterization of microbial antigens. The originality of such immunoproteomic approaches resides in their application in large-scale studies for rapid serotyping of micro-organisms, evaluation of immunomes and could be proposed in the development and monitoring of vaccines.     

A decade of improvements in quantification of gene expression and internal standard selection

Major improvements have been made in mRNA quantification and internal standard selection over the last decade. Our aim in this paper is to present the main developments that are of interest for practical laboratory work, contrasting the situation as it is now with the one of ten years ago, and presenting some excellent examples of what can be done today. Specifically, we will mainly discuss Real-Time RT-PCR major improvements that have been performed in the following areas: the most commonly used quantification techniques, the mathematical and software tools created to help researchers in their work on internal standard selection, the availability of detection chemistries and technical information and of commercial tools and services. In addition to mRNA quantification, we will also discuss some aspects of non-coding RNA and protein quantification. In addition to technical improvements, the development of international cooperation and the creation of technical databases are likely to represent a major tool for the future in the standardization of gene expression quantification.     

Comparaison de l’IRM de diffusion et de la TEP/TDM au FDG dans le bilan des lymphomes

PurposeDiffusion weighted MRI (DW-MRI) sequences appear as a promising functional technique supplementary to morphologic MRI for oncology purposes. We evaluated the results of DW-MRI for the staging of lymphomas, compared to FDG PET/CT.MethodsTwenty-seven patients with lymphoma referred for FDG PET/CT (initial staging, relapse or treatment evaluation) were prospectively included. They underwent MRI including free breathing DW and T2 weighted imaging. Lymph node areas and organs involvement were listed for each modality and compared using Cohen's kappa (κ) test. MRI performances were evaluated using FDG PET as the gold standard. The results of PET and MRI were compared (with respect to the final staging by the haematologist).ResultsRegarding the lymph nodes, 154 involved areas were detected by MRI out of the 184 detected by PET, that is an excellent concordance (κ = 0.87), sensitivity of 0.84 and specificity of 1. Concordance and sensitivity were inferior for extranodal disease (notably bone lesions) with 27 lesions detected by MRI out of the 40 viewed with PET. Regarding pre-treatment evaluation, two patients were understaged both with PET and MRI (bone marrow involvement); assessment of stage was concordant for both modalities in 18 patients out of 21.ConclusionsPerformance of MRI including DW images was close to that of FDG PET/CT for lymph node areas involvement. Further studies are needed to assess its sensitivity for extranodal lesions, and its accuracy for determining the stage of the disease.     

Are the interactions between recombinant prion proteins and polymeric surfaces related to the hydrophilic/hydrophobic balance?

New non-fouling tubes are developed and their influence on the adhesion of neuroproteins is studied. Recombinant prion proteins are considered as a single component representative of hydrophobic proteins. Samples are stored for 24?h at 4?°C in tubes coated with two different coatings: poly(N-isopropylacrylamide) as a hydrophilic surface and a plasma-fluorinated coating as a hydrophobic one. The protein adhesion is monitored by ELISA tests, XPS and confocal microscopy. It appears that the highest recovery of recombinant prion protein in the liquid phase is obtained with the hydrophilic surface while the hydrophobic character of the storage tube induces an important amount of biological loss. However, the recovery is not complete even for tubes coated with poly(N-isopropylacrylamide).     

Immunoquantitative real-time PCR for detection and quantification of Staphylococcus aureus enterotoxin B in foods

A real-time immunoquantitative PCR (iqPCR) method for detection of Staphylococcus aureus enterotoxin B (SEB) was developed and evaluated using both pure cultures and foods. The assay consisted of immunocapture of SEB and real-time PCR amplification of the DNA probe linked to the detection antibody. iqPCR was compared to an in-house enzyme-linked immunosorbent assay (ELISA) using the same couple of capture-detection antibodies and to commercial kits for detection of S. aureus enterotoxins (SE). The iqPCR was approximately 1,000 times more sensitive (<10 pg ml(-1)) than the in-house ELISA and had a dynamic range of approximately 10 pg ml(-1) to approximately 30,000 pg ml(-1). iqPCR was not inhibited by any of the foods tested and was able to detect SEB present in these foods. No cross-reactivity with SE other than SEB was observed. Application of iqPCR for detection of SEB in cultures of S. aureus revealed the onset of SEB production after 4 h of incubation at 22, 37, and 42 degrees C, which was in the first half of the exponential growth phase. The total amounts of SEB produced by the two strains tested were larger at 42 degrees C than at 37 degrees C and were strain dependent.     

Immunoquantitative Real-Time PCR for Detection and Quantification of Staphylococcus aureus Enterotoxin B in Foods

A real-time immunoquantitative PCR (iqPCR) method for detection of Staphylococcus aureus enterotoxin B (SEB) was developed and evaluated using both pure cultures and foods. The assay consisted of immunocapture of SEB and real-time PCR amplification of the DNA probe linked to the detection antibody. iqPCR was compared to an in-house enzyme-linked immunosorbent assay (ELISA) using the same couple of capture-detection antibodies and to commercial kits for detection of S. aureus enterotoxins (SE). The iqPCR was approximately 1,000 times more sensitive (<10 pg ml⁻¹) than the in-house ELISA and had a dynamic range of approximately 10 pg ml⁻¹ to approximately 30,000 pg ml⁻¹. iqPCR was not inhibited by any of the foods tested and was able to detect SEB present in these foods. No cross-reactivity with SE other than SEB was observed. Application of iqPCR for detection of SEB in cultures of S. aureus revealed the onset of SEB production after 4 h of incubation at 22, 37, and 42°C, which was in the first half of the exponential growth phase. The total amounts of SEB produced by the two strains tested were larger at 42°C than at 37°C and were strain dependent.     

An immuno-PF2D-MS/MS proteomic approach for bacterial antigenic characterization: to Bacillus and beyond

We are confronted daily to unknown microorganisms that have yet to be characterized, detected, and/or analyzed. We propose, in this study, a multidimensional strategy using polyclonal antibodies, consisting of a novel proteomic tool, the ProteomeLab PF2D, coupled to immunological techniques and mass spectrometry (i-PF2D-MS/MS). To evaluate this strategy, we have applied it to Bacillus subtilis, considered here as our unknown bacterial model.     

Molecular phylogeny of <Emphasis Type="Italic">Pisolithus</Emphasis> species from Moroccan forest woodlands

The phylogenetic relationships among 200 Pisolithus basidiomata collected from pine, oak, and eucalypt forests and rockrose scrubs in Morocco were investigated. Using PCR-RFLP analysis of the internal transcribed spacer (ITS) of ribosomal DNA, this collection could be divided into 5 groups, by using PCR-RFLP analysis of the internal transcribed spacer (ITS) of ribosomal DNA. The ITS of a representative basidioma of each group was sequenced, and a phylogenetic analysis was performed. The dendrogram suggests that at least five Pisolithus species are present in Morocco. Pisolithus basidiomata collected in the Pinus and Quercus forests correspond to Pisolithus arrhizus and P. species 4 as previously described by Martin and colleagues in 2002. Those collected from the eucalyptus forests, under E. gomphocephala and E. camaldulensis, correspond to P. albus and P. microcarpus. Basidiomata collected from the rockrose scrubs, under Cistus crispus, C. monspeliensis or C. salviifolius, are all identified as Pisolithus species 3. Phylogenetic analyses showed that our different Pisolithus grouped well with Pisolithus specimens from other geographical origins.