ABSTRACT
BACKGROUND: The exact role of expectation in conditioned analgesia is still elusive as it is not clear whether conditioning is an automatic process or rather it is cognitively mediated. This study is aimed at understanding the role of explicit verbal information in conditioned analgesia. METHODS: Two groups of healthy subjects received a conditioning procedure whereby two visual cues were paired with increase and decrease in stimulus intensity. In the 'conditioning/verbal information' group (VER), subjects were informed about the meaning of the cues, whereas no information was given to the second group (noVER). After two conditioning blocks, an evocation session was run in which the stimulus intensity was the same, irrespective of the cues. Pain perception was assessed according to a numerical rating scale from 0 (no pain) to 10 (maximal pain). The N2-P2 component of laser-evoked potentials (LEP) was used as an index of index of brain responses to nociceptive stimuli. RESULTS: In the evocation session, only the VER group reported a decrease in pain rating and LEP amplitude when the cues were presented, suggesting that the visual-analgesic association does not occur without explicit verbal information. CONCLUSIONS: In line with the cognitive theory of conditioning, our results indicate that just pairing a cue with different pain stimulus intensities is not sufficient, per se, to produce a learning process. What matters is the informational cognitive content of the cue, i.e. the meaning assigned to the cue itself. These findings may help understand the mechanisms of conditioned analgesia and more in general of learning.
Subject(s)
Analgesics/therapeutic use , Conditioning, Psychological/physiology , Pain Management , Pain/psychology , Placebo Effect , Adult , Analgesia/methods , Brain/drug effects , Female , Humans , Laser-Evoked Potentials/drug effects , Male , Pain Threshold/drug effects , Pain Threshold/physiology , Speech , Young AdultABSTRACT
A new HLA-DRB5 allele, HLA-DRB5*0113, has been identified in an Italian patient during routine HLA typing in order to activate a bone marrow donor search. HLA typing was performed by different molecular biology techniques, and the results showed that the HLA-DRB5*0113 allele differs from HLA-DRB5*010101 allele for three nucleotide substitutions at codons 57 (GAC-->GAT; Asp) and 58 (GCT-->GAG; Ala-->Glu) of exon 2.
Subject(s)
Bone Marrow Transplantation/immunology , HLA-DR Antigens/genetics , Histocompatibility Testing/methods , Alanine/chemistry , Alanine/genetics , Alleles , Amino Acid Sequence , Amino Acid Substitution , Base Sequence , Glutamic Acid/chemistry , Glutamic Acid/genetics , HLA-DRB5 Chains , Humans , Male , Middle Aged , Molecular Sequence Data , MutationABSTRACT
Abstract A new human leucocyte antigen (HLA)-DRB1 allele, HLA-DRB1*1149, has been identified in three members of an Italian family during routine sequence based typing. This new allele differs from HLA-DRB1*110101 only for a single nucleotide substitution at position 113 of exon 2 resulting in an amino acid change from Valine (GTG) to Alanine (GCG) at codon 38.
