Chordoma of the base of skull. Apropos of 3 cases]

The authors report 3 cases of skull base chordomas. In 2 cases, skull radiographies and computed tomography found lytic lesions of sphenoid and clivus, with calcifications into the tumors. In the third case, radiological findings suggest a naso pharynx tumor.     

Study on the decomposition of 2-chloroethylnitro- sosulfamides (CENS) in serum using HPLC on-line solid phase extraction

In this paper we have investigated the kinetic decomposition of 2-chloroethylnitrososulfamides (CENS) in fetal calf serum. The study was monitored by on-line solid phase extraction linked to RP-LC-MS. We demonstrated that CENS are less stable in fetal calf serum than in aqueous buffer at pH 7.4 and 37 degrees C. Moreover, we have shown that partition coefficient of CENS can be correlated to the kinetics decomposition, and we observe that the stability is better for lipophilic CENS. The different metabolites after decomposition have been tentatively identified by RP-HPLC-MS. This study indicates the formation of several metabolites resulting from a mechanism of decomposition more complex than in aqueous phosphate buffer, nevertheless, leading to the same main products.     

Deletion of the V1/V2 region does not increase the accessibility of the V3 region of recombinant gp125

Previous analyses of HIV-1 surface glycoprotein indicate that both the V1/V2 region and the interaction of gp120 with CD4 influence the accessibility of the V3 region on gp120. In this study we investigated the accessibility of the V3 region of HIV-2 recombinant gp125 proteins using V3-specific mAbs (7C8 and 3C4) and analyzed the binding kinetics of soluble CD4 (sCD4) to recombinant HIV-1 gp120 and HIV-2 gp125 proteins by surface plasmon resonance (SPR) analysis. Our results indicated that 7C8 recognized monomers of gp125 and gp125Delta v1v2, (lacking the V1/V2 region) while 3C4 was sensitive to the conformation of gp125, recognizing only oligomers of gp125Delta v1v2. Furthermore, SPR analysis of 7C8 binding to gp125 demonstrated that the deletion of the V1/V2 region did not increase the accessibility of the V3 region in gp125Delta v1v2. Comparative SPR analyses of sCD4 binding HIV recombinant surface glycoproteins revealed a lower affinity of sCD4 to gp125 as compared to gp120. Moreover, the analyses suggest that conformational changes only occur in HIV-1 gp120 upon interaction with CD4. We hypothesize that the V3 region is accessible in HIV-2 gp125 and thus may not require interaction with CD4 to induce conformational reorientation of the V1/V2 region.     

High diversity of HIV type 1 in Algeria

We have sequenced different genes of HIV-1 strains from infected individuals recruited in various geographic parts of Algeria; phylogenetic trees were constructed yielding molecular characterization of these strains. Subtype B accounts for 56% of the samples studied and is therefore the predominant subtype, particularly in the north part of the country; but there is a high diversity of the virus including CRF02_AG, CRF06_cpx, CRF02/CRF06 interrecombinants, and different other intersubtype and/or inter-CRF recombinants. The prevalence of these non-B viruses increases in the south part of Algeria that borders sub-Saharan African countries. The high diversity of HIV-1 in Algeria has implications for virological follow-up, resistance surveys, and vaccine design.     

Une localisation exceptionnelle du kyste hydatique: à propos de deux cas

Introduction

The hydatid cyst is a cosmopolitan parasitic infection that constitutes a problem of public health in developing countries’ areas of breeding.

Material and methods

The aim of this work is to report on the condition of extraordinary location. We report two cases of hydatid cyst of the right buttock. The diagnosis was confirmed by ultrasound scan of the soft parts. The treatment was surgical.

Discussion

The muscle hydatic cyst is a rare disease and achievement of the buttock is exceptional, so you must always think of it in subjects living in high endemic countries. The eradication of this disease is based on prophylaxis.

Conclusion

The hydatid cyst of soft parts is a rare tumor that grows slow, with local extension. You have to think of this diagnosis, especially in subjects from high endemic countries and seek explorations needed to make the diagnosis in time and avoid therapeutic errors.