A 17-mer sequence was selected as a model to study the influence of modifications of terminal ends both on the conformational of a peptide and on its antigenicity towards naturally developing antibodies. This sequence corresponded to a tandemly repeated motif, found in a long repetitive region, with high helical propensity, of a Plasmodium falciparum liver-stage antigen (LSA-1), immunogenic in man. Our model peptide was synthesized with ionizable or non-ionizable ends, or modified in both extremities by introduction of the helix-promoting residue alpha-aminoisobutyric acid (Aib). Helical contribution, absent in the 17 amino-acid sequence possessing ionizable ends, was detectable when non-ionizable ends were introduced, and dramatically increased in the Aib-modified analogue. The presence of ionizable ends totally abolished reactivity towards human sera, otherwise detectable with the peptide possessing non-ionizable ends. While modification by Aib residues was neither detrimental nor beneficial to antigenicity in solution, it clearly resulted in an improved sensitivity of the specific antibody detection when used as solid-phase antigen in ELISA.

Amino Acid Sequence↗

PubMedDate not supplied

Modelling the relationships between training, anxiety, and fatigue in elite athletes.

This study investigated the effects of 40-week training on anxiety and perceived fatigue in four elite triathletes. Anxiety and perceived fatigue were self-reported by the subjects twice a week by the way of a specific questionnaire and were linked by a mathematical model to the training loads calculated from the exercise heart rate. A significant relationship (r=0.32; p<0.001) between the training loads and anxiety was identified using a two-component model: a first, negative (i.e., anxiety decreased) short-term (tau (1)=23 days) function and a second, positive long-term (tau (2)=59 days) function. The relationship between the training loads and perceived fatigue was significant (r=0.30; p<0.001), with one negative function (tau (1)=4 days). This mathematical model can potentially describe the relationships between training loads and anxiety or perceived fatigue and may improve both the adjustment of the duration of tapering and the early detection of staleness.

Adult↗

PubMedDate not supplied

[Neonatal form of isovaleric acidemia. Apropos of a new case].

The case reported concerns a 18 day-old girl who was hospitalized for severe toxemia. The nauseous smell, and significant ketonuria led us to suspect a disorder in amino-acids metabolism. Diagnosis was proven by gas chromatography. With adequate diet, evolution was favourable and the child had a normal psycho-motor development.

Amino Acid Metabolism, Inborn Errors↗

PubMedDate not supplied

[Case of tuberculous appendicitis].

Explore the source record for details and available documents.

Adult↗