Lieu de contrôle chez les obèses : traduction et première étude de validation de l’échelle du lieu de contrôle du poids de saltzer

The objectives of this study are to enable the use of the concept of locus of control in the treatment of obese subjects and to verify if the presence of an alimentary disorder influences the belief in the weight’s control. The translation and validation in French is also part of the objective. We translated into French Saltzer’s specific scale of Weight Locus of Control (WLOC: weight locus of control) and then examined it’s validity. Then we compared it on general scales of the place of control (IPC of Levenson and SOC-3 of Paulhus). The subjects were both classified according to the presence of eating disorders (ED). A sample of 46 obese women (IMC>30) was tested, 20 of them without ED, and 26 with, associated to the presence ED, according to the criteria of the DSM-IV.The internal validity of WLOC is rather satisfactory. It correlates negatively with internality (IPC), personal control and interpersonal control (SOC-3). ED at the obese subjects are related on the externality of weight control and the externality of personal control. Obese subjects without ED believe more in weight control by themselves and personal control that the obese subjects with ED (Eating Disorders). Finally the scale of weight locus of control (WLOC) remains the most adapted in the treatment and the study of the obese subject.     

Growth and toxin production in the ciguatera-causing dinoflagellate Gambierdiscus polynesiensis (Dinophyceae) in culture

The growth and toxin production in a clonal strain of Gambierdiscus polynesiensis, TB-92, was examined in batch culture conditions. The mean growth rate at exponential phase was (0.13 ± 0.03) division day⁻¹. Regardless of the age of cultures, all mice injected with dichloromethanolic and methanolic extracts showed symptoms specific to ciguatoxin (CTX) and maitotoxin (MTX) bioactivity, respectively. The highest total toxicity assessed in TB-92 cultures was 10.4 × 10⁻⁴ mouse unit cell⁻¹. The toxin production pattern reveals an enhanced cellular toxin content with the age of the culture. CTX- and MTX-like compounds each accounted for approx. 50% of the total toxicity of TB-92 cultures, except in aged cells where CTXs were dominant. The high ciguatoxic activity of TB-92 was further confirmed in dichloromethanolic extracts by means of the receptor-binding assay. The highest CTX level monitored at late stationary phase was (11.9 ± 0.4) pg P-CTX-3C equiv cell⁻¹. Further HPLC and LC-MS analysis revealed the presence of five CTXs congeners in lipid-soluble extracts, i.e. CTX-3C, -3B, -4A, -4B and M-seco-CTX-3C, and of new CTX congeners. Toxin composition comparison between two G. polynesiensis strains suggests that the toxin profile is a stable characteristic in this species. G. polynesiensis clones also proved inherently more toxic than other Gambierdiscus species isolated from other geographical areas.     

Collagen distribution in human membranous glomerulonephritis

In membranous glomerulonephritis (MGN), thickening of the glomerular basement membrane (GBM) is partly due to the accumulation of basement membrane material between and around immune deposits located on the epithelial aspect of the GBM. We investigated the distribution of type IV collagen chains (1/2, 3, 4, 5, 6) and of types I, III, V, and VI collagen in the glomeruli from 16 patients, by indirect immunofluorescence in 13 and the high-resolution immunogold technique in 6. No changes were detected in stage I MGN. The spiky projections of the GBM in stage II MGN and the basement membrane layers encircling immune deposits in stage III contained the 3, 4, and 5 chains of type IV collagen. In contrast, the 1/2 chains of type IV, as well as type VI collagen accumulated in the subendothelial aspect of the GBM. No significant staining for types I, III, and V collagens or for the 6 chain of type IV collagen was detected. The results show that, as in the normal glomeruli, the different chains of type IV collagen are not co-distributed in the glomerular extracellular matrix in MGN. They also indicate that type IV collagen chains and type VI collagen play an important role in the thickening of the GBM in human MGN.     

Comparison of the diagnostic workup of women referred at non-blinded or blinded double reading in a population-based screening mammography programme in the south of the Netherlands

Background:

To determine whether referred women experience differences in diagnostic workup at non-blinded or blinded double reading of screening mammograms.

Methods:

We included a consecutive series of respectively 42.996 and 44.491 screens, double read either in a non-blinded or blinded manner between 2009 and 2011. This reading strategy was alternated on a monthly basis.

Results:

The overall ultrasound-guided core needle biopsy (CNB) rate and stereotactic CNB (SCNB) rate per 1000 screens were higher at blinded than at non-blinded reading (7.5 vs 6.0, P=0.008 and 8.1 vs 6.6, P=0.009). Among women with benign workup, these rates were higher at blinded reading (2.6 vs 1.4, P<0.001 and 5.9 vs 4.7, P=0.013). The benign biopsy rates were higher at blinded double reading (P<0.001), whereas the positive predictive value of biopsy did not differ (P=0.103).

Conclusions:

Blinded double-reading results in higher overall CNB and SCNB rates than non-blinded double reading, as well as a higher benign biopsy rate.     

Postpartum behaviour as predictor of weight change from before pregnancy to one year postpartum

Background  

Postpartum weight retention affects many women and increases the risk of becoming overweight. The research objective was to study modifiable factors contributing to weight change at one year postpartum.     

Inhibition of carcinogen-bioactivating cytochrome P450 1 isoforms by amiloride derivatives

We examined the effects of amiloride derivatives, especially 5-(N-ethyl-N-isopropyl)amiloride (EIPA), on the activity of cytochrome P450 (CYP) 1 isoforms, known to metabolize carcinogenic polycyclic aromatic hydrocarbons (PAHs), such as benzo(a)pyrene (BP), into mutagenic metabolites and whose cellular expression can be induced through interaction of PAHs with the arylhydrocarbon receptor. EIPA was found to cause a potent and dose-dependent inhibition of CYP1-related ethoxyresorufine O-deethylase (EROD) activity in both liver cells and microsomes. It also markedly reduced activity of human recombinant CYP1A1 enzyme through a competitive mechanism; activities of other human CYP1 isoforms, i.e. CYP1A2 and CYP1B1, were also decreased. However, EIPA did not affect BP-mediated induction of CYP1A1 mRNA and protein levels in rat liver cells, likely indicating that EIPA does not block activation of the arylhydrocarbon receptor by PAHs. Inhibition of CYP1 activity by EIPA was associated with a decreased metabolism of BP, a reduced formation of BP-derived DNA adducts and a diminished BP-induced apoptosis in liver cells. The present data suggest that amiloride derivatives, such as EIPA, may be useful for preventing toxicity of chemical carcinogens, such as PAHs, through inhibition of CYP1 enzyme activity.     

Methylenetetrahydrofolate reductase gene polymorphisms and response to fluorouracil-based treatment in advanced colorectal cancer patients

Methylenetetrahydrofolate reductase (MTHFR) controls intracellular CH2FH4 concentrations (required for optimal fluoropyrimidine efficacy) by irreversibly converting CH2FH4 into 5-methyltetrahydrofolate. MTHFR 677C>T and 1298A>C polymorphisms are linked to altered enzyme activity. Thus, mutated MTHFR tumours should, in theory, be more sensitive to 5-fluorouracil (5FU) than wild-type tumours. MTHFR polymorphisms in position 677 and 1298 were analysed in 98 colorectal cancer patients with unresectable liver metastases (57 men, 41 women, mean age 64 years) receiving 5FU-folinic acid. 677C>T and 1298A>C genotypes were determined simultaneously by melting curve analyses on liver metastases. 677C>T genotype distribution was 46.9% wt/wt, 34.7% wt/mut and 18.4% mut/mut; that of 1298A>C was 52.0% wt/wt, 35.7% wt/mut and 12.3% mut/mut. The response rate was not related to 1298A>C genotype but was significantly linked to 677C>T genotype (response rate: 40%, 21% and 56% in wt/wt, wt/mut and mut/mut, respectively; P = 0.040), with an increased response rate in mut/mut tumours relative to wt/wt (odds ratio = 1.88). Thymidylate synthase activity measured in metastases was a significant predictor of 5FU responsiveness and the addition of the 677C>T genotype improved model prediction. MTHFR 1298A>C polymorphism was significantly linked to specific survival, with homozygous mutated patients having the worst prognosis (P = 0.009, relative risk = 2.48 in mut/mut versus wt/wt). MTHFR 1298A>C genotype remained a significant predictor in a multivariate analysis including metastasis characteristics. The results suggest that MTHFR genotypes are relevant and independent factors of patient outcome in 5FU-based treatment of advanced colorectal cancer.     

Chronic valproate treatment blocks D2-like receptor-mediated brain signaling via arachidonic acid in rats

Background and objective

Hyperdopaminergic signaling and an upregulated brain arachidonic acid (AA) cascade may contribute to bipolar disorder (BD). Lithium and carbamazepine, FDA-approved for the treatment of BD, attenuate brain dopaminergic D₂-like (D₂, D₃, and D₄) receptor signaling involving AA when given chronically to awake rats. We hypothesized that valproate (VPA), with mood-stabilizing properties, would also reduce D₂-like-mediated signaling via AA.

Methods

An acute dose of quinpirole (1 mg/kg) or saline was administered to unanesthetized rats that had been treated for 30 days with a therapeutically relevant dose of VPA (200 mg/kg/day) or vehicle. Regional brain AA incorporation coefficients, k*, and incorporation rates, J_in, markers of AA signaling and metabolism, were measured by quantitative autoradiography after intravenous [1-¹⁴C]AA infusion. Whole brain concentrations of prostaglandin (PG)E₂ and thromboxane (TX)B₂ also were measured.

Results

Quinpirole compared to saline significantly increased k* in 40 of 83 brain regions, and increased brain concentrations of PGE₂ in chronic vehicle-treated rats. VPA treatment by itself reduced concentrations of plasma unesterified AA and whole brain PGE₂ and TXB₂, and blocked the quinpirole-induced increments in k* and PGE₂.

Conclusion

These results further provide evidence that mood stabilizers downregulate brain dopaminergic D₂-like receptor signaling involving AA.     

Effective biennial mammographic screening in women aged 40-49

BackgroundThe United Kingdom is currently moving the age limit for invitation in its national breast screening programme downwards from 50 to 47. In contrast, the US Preventive Services Task Force concluded that, because of borderline statistical significance on effectiveness of mammographic screening, the current evidence is insufficient to advise screening in women aged 40–49.Material and methodsWe designed a case-referent study to investigate the effect of biennial mammographic screening on breast cancer mortality for women in their forties. In Nijmegen, the Netherlands, screening started in 1975. A total of 272 breast cancer deaths were identified, and 1360 referents aged 40–69 were sampled from the population invited for screening. Effectiveness was estimated by calculating the odds ratio (OR) indicating the breast cancer death rate in screened versus unscreened women.ResultsIn women aged 40–49, the effect of screening was OR = 0.50 (95% confidence interval (CI) = 0.30–0.82). This result is similar to those aged 50–59 (OR = 0.54; 95% CI = 0.35–0.85) and 60–69 (OR = 0.65; 95% CI = 0.38–1.13).ConclusionOur results add convincing evidence about the effectiveness of biennial mammographic screening in women aged 40–49.