Le troisième corps

Book published by Le Fram (2004)

Hiv-1 Gp41 And Gp160 Are Hyperthermostable Proteins In A Mesophilic Environment - Characterization Of Gp41 Mutants

in European Journal of Biochemistry (2004), 271(8), 1566-79

HIV gp41(24-157) unfolds cooperatively over the pH range of 1.0-4.0 with T(m) values of > 100 degrees C. At pH 2.8, protein unfolding was 80% reversible and the DeltaH(vH)/DeltaH(cal) ratio of 3.7 is ... [more ▼]

HIV gp41(24-157) unfolds cooperatively over the pH range of 1.0-4.0 with T(m) values of > 100 degrees C. At pH 2.8, protein unfolding was 80% reversible and the DeltaH(vH)/DeltaH(cal) ratio of 3.7 is indicative of gp41 being trimeric. No evidence for a monomer-trimer equilibrium in the concentration range of 0.3-36 micro m was obtained by DSC and tryptophan fluorescence. Glycosylation of gp41 was found to have only a marginal impact on the thermal stability. Reduction of the disulfide bond or mutation of both cysteine residues had only a marginal impact on protein stability. There was no cooperative unfolding event in the DSC thermogram of gp160 in NaCl/P(i), pH 7.4, over a temperature range of 8-129 degrees C. When the pH was lowered to 5.5-3.4, a single unfolding event at around 120 degrees C was noted, and three unfolding events at 93.3, 106.4 and 111.8 degrees C were observed at pH 2.8. Differences between gp41 and gp160, and hyperthermostable proteins from thermophile organisms are discussed. A series of gp41 mutants containing single, double, triple or quadruple point mutations were analysed by DSC and CD. The impact of mutations on the protein structure, in the context of generating a gp41 based vaccine antigen that resembles a fusion intermediate state, is discussed. A gp41 mutant, in which three hydrophobic amino acids in the gp41 loop were replaced with charged residues, showed an increased solubility at neutral pH. [less ▲]

Investigation of nursing strategies to improve adaptation to extra-uterine life in Belgian White and Blue calves and Holstein calves during the first 24 hours after birth.

in 23rd World Buiatrics Congress (2004)

L'astronomie en Europe à la fin du XVIIIè siècle (1789-1802)

Conference (2004)

Survivin enhances radiation resistance in primary human glioblastoma cells via caspase-independent mechanisms.

in Oncogene (2004), 23(45), 7494-506

The observed radioresistance of human glioblastoma multiforme (GBM) poses a major challenge, which, if overcome, may lead to significant advances in the management of this patient population. There is ... [more ▼]

The observed radioresistance of human glioblastoma multiforme (GBM) poses a major challenge, which, if overcome, may lead to significant advances in the management of this patient population. There is accumulating evidence from correlative studies that Survivin expression is associated with increased malignant potential of human gliomas. The purpose of this study was to investigate whether Survivin plays a direct role in mediating radiation resistance in primary human glioma cell lines, and, if so, investigating the underlying mechanisms. Our panel of GBM cell lines included two that were relatively radiation resistant (GM20 and GM21) and two that were more radiation sensitive (GM22 and GM23), which demonstrated differential levels of Survivin expression between the two groups. Through the use of adenoviral vectors containing either dominant-negative (pAd-S(T34A)) or wild-type Suvrivin (pAd-S(WT)), we were able to inactivate or overexpress Survivin, respectively. Our findings suggest that Survivin plays a critical role in mediating radiation resistance in primary GBM cells, in part through suppression of apoptotic cell death via a caspase-independent manner. We have identified novel mechanisms by which Survivin may enhance tumor cell survival upon radiation exposure such as regulation of double-strand DNA break repair and tumor cell metabolism, which were most evident in the radiation-resistant cell lines. These differences in Survivin function both in radiation-resistant vs radiation-sensitive cell lines and in the presence vs absence of radiation exposure warrant further investigation and highlight potentially important mechanisms of radiation resistance in these tumors. [less ▲]

Resuscitation and monitoring after abdominal trauma

in Imaging and intervention in abdominal trauma (2004)

Le triphosphate de thiamine : une nouvelle molécule de signalisation ?

Scientific conference (2004)

Astronomes célèbres et astronomes moins connus ... (4) Bailly

in Galactée (2004), 40

Le rossignol instrumental: poésie, musique, modernité

Book published by Peeters/Vrin (2004)

Déficience du système glutathion chez le cheval de course

in 30ème Journée de la Recherche Equine, Les Haras Nationaux (2004)