PubMed Health⌕ Search

Biomedical subjects

S Lafont

Publications and source records attributed to S Lafont.

41 records · Page 3Linked to original sources
PubMed1982

An attempt to localize the vaccinating power of Klebsiella pneumoniae ribosomal preparations using saccharose-gradient ultracentrifugation.

The study of the vaccinating power of ribosomal vaccines against Klebsiella pneumoniae led us to define the chemical nature which supports this protective activity. We tried to separate this support and the ribosomes by sucrose gradient ultracentrifugation. We isolated high protective membrane vesicles by this technique applied to salt-washed ribosomal preparations. When the ribosomal preparations were exposed to SDS, the protective activity was conserved all along the gradient, with no correlation with the ribosome concentration. The addition of bovine serum albumin to the ribosomal preparation focused the protective activity on the ribosomal peak. No correlation was observed between the response to capsular polysaccharide and the vaccinating power of the fractions.

Ammonium Chloride↗
PubMedDate not supplied

Plasma insulin-like growth factor I levels in the elderly: relation to plasma dehydroepiandrosterone sulfate levels, nutritional status, health and mortality.

BACKGROUND: Insulin-like growth factor I (IGF-I) has beneficial metabolic effects. Because plasma IGF-I levels have been reported to be enhanced by dehydroepiandrosterone (DHEA) administration, it has been suggested that the IGF-I may be implicated in some of the reported associations between low DHEA sulfate (DHEAS) levels and impaired health measures in elderly subjects. The nutritional status, which also regulates plasma IGF-I levels, is also an important determinant of health outcome. OBJECTIVE: We sought to investigate the associations between plasma IGF-I levels and plasma DHEAS levels, nutritional status, health, and mortality in the elderly. METHODS: In 256 community-dwelling subjects aged 65-101 years, enrolled in the Paquid study, a health questionnaire was used to acertain their functional disabilities, any history of medical disorders, self-perceived health, depressive symptoms, and their cognitive function. Biological measurements included levels of plasma IGF-I, albumin, transthyretin, and DHEAS. Mortality data were available for 6 years following blood sampling. RESULTS: In this elderly population with no impairment in nutritional status, the plasma IGF-I levels decreased significantly with age (p = 0.02). The plasma IGF-I levels correlated positively with those of transthyretin (p = 0.0001). IGF-I also correlated with DHEAS (p = 0.04), but the correlation did not remain significant after adjustment for age. As opposed to SDHEA, the plasma IGF-I levels did not correlate with the results from the health questionnaire. The baseline IGF-I values in the highest tertile were associated with a higher risk of short-term mortality than those in the lowest tertile (RR = 8.4 at 2 years, p = 0.007). CONCLUSIONS: Our results suggest that IGF-I is not connected with the association between low plasma DHEAS levels and the impaired results from the health questionnaire. The relationship between plasma IGF-I highest levels and mortality should be further explored.

Age Factors↗
PubMedDate not supplied

A randomized controlled trial of cognitive therapy versus intensive behavior therapy in obsessive compulsive disorder.

BACKGROUND: The study was designed to compare cognitive therapy (CT) with intensive behavior therapy (BT) in obsessive-compulsive disorder (OCD) and to study their change process. METHODS: Sixty-five outpatients with DSM-4 OCD were randomized into 2 groups for 16 weeks of individual treatment in 3 centers. Group 1 received 20 sessions of CT. Group 2 received a BT program of 20 h in two phases: 4 weeks of intensive treatment (16 h), and 12 weeks of maintenance sessions (4 h). No medication was prescribed. RESULTS: Sixty-two patients were evaluated at week 4, 60 at week 16 (post-test), 53 at week 26 and 48 at week 52 (follow-up). The response rate was similar in the 2 groups. The Beck Depression Inventory (BDI) was significantly more improved by CT (p = 0.001) at week 16. The baseline BDI and Obsessive Thoughts Checklist scores predicted a therapeutic response in CT, while the baseline BDI score predicted a response in BT. At week 16, only the changes in Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and a scale measuring the interpretation of intrusive thoughts correlated in CT, while the changes in Y-BOCS, BDI, and interpretation of intrusive thoughts correlated in BT. Improvement was retained at follow-up without a between-group difference. The intent-to-treat analysis (last observation carried forward) found no between-group differences on obsessions, rituals and depression. CONCLUSIONS: CT and BT were equally effective on OCD, but at post-test CT had specific effects on depression which were stronger than those of BT. Pathways to improvement may be different in CT and BT. The outcomes are discussed in the light of an effect size analysis.

Adult↗
PubMedDate not supplied

[An ELISA study of the intestinal and serum anti-LPS antibody response in BALB/c mice fed with various mutants of "Salmonella typhi-murium" (author's transl)].

The specific anti-LPS serum antibody response in BALB/c mice, before and after an oral booster with different non-pathogenic strains of Salmonella typhi-murium, was measured by an ELISA technique. Serum response to LPS was found to depend on the length of the LPS polysaccharide moiety in "rough" mutants. The M206 "smooth" mutant induced a less marked anti-LPS response. The immunogenicity of the polysaccharidic "core" appears to be modified by the O antigen. The specific antibody response in the gut only becomes marked following after booster of Ra, Rc and M206 mutants.

Animals↗