Hormonal treatment, mild cognitive impairment and Alzheimer's disease

A plethora of in vitro and in vivo studies have supported the neuroprotective role of estrogens and their impact on the neurotransmitter systems implicated in cognition. Recent hormonal replacement therapy (HRT) trials in non-demented postmenopausal women suggest a temporary positive effect (notably on verbal memory), and four meta-analyses converge to suggest a possible protective effect in relation to Alzheimer's disease (reducing risk by 29 to 44%). However, data from the only large randomized controlled trial published to date, the Women's Health Initiative Memory Study, did not confirm these observations and have even suggested an increase in dementia risk for women using HRT compared to controls. Apart from methodological differences, one key shortcoming of this trial has probably been the focus on late-onset (postmenopausal) hormonal changes, i.e. at a time when the neurodegenerative process has already begun and without taking into account individual lifetime exposure to hormone variability. Multifactorial models based on an exhaustive view of all hormonal events throughout the reproductive life (rather than on a specific exposure to a given steroid) together with other risk factors (notably genetic risk factors related to estrogen receptor polymorphisms) should be explored to clarify the role of hormonal risk factors, or protective factors for cognitive dysfunction and dementia.     

Mycobacterium heckeshornense tenosynovitis

We describe the first case of tenosynovitis due to Mycobacterium heckeshornense, a mycobacterium characterized in 2000 and only incriminated in a few previous cases of infections. Molecular identification of this pathogen included 16S rRNA and hsp65 gene sequencing. M. heckeshornense may cause a wide spectrum of human infectious diseases and may be underestimated due to its phenotypic relatedness with Mycobacterium xenopi.     

TEM-24 Produced by Four Different Species of Enterobacteriaceae, Including Providencia rettgeri, in a Single Patient

Four species of members of the family Enterobacteriaceae harboring extended-spectrum beta-lactamase (ESBL) were recovered in a single patient hospitalized in an intensive care unit. Among these isolates, we describe for the first time an ESBL-producing Providencia rettgeri strain. Bacteria from the same species were shown to be genetically related by pulsed-field gel electrophoresis analysis. These strains produced the same TEM derivative ESBL, characterized as TEM-24. This enzyme had the peculiarity of being encoded by a large conjugative plasmid of 180 kb, never previously described for such an ESBL.     

Micropuncture study of renal magnesium transport in magnesium-loaded rats.

Mg transport in the deep loop of Henle was studied in 15 young rats (50-60 g) after acute systemic Mg loading (UFMg (ultrafilterable Mg) 4.77 meq/liter). Intratubular Mg was measured with a recently described fluorometric microtechnique. The mean values of the TF/P inulin and TF/UF Mg ratios were 3.32 +/- 0.13 and 4.25 +/- 0.17, respectively. The proportion of filtered Mg recovered in this part of the nephron was therefore 131.2 +/- 5.0%, indicating that an appreciable amount of Mg entered the lumen prior to the sites of puncture. A significant correlation between the TF/P inulin and TF/UF Mg ratios suggests that water reabsorption also contributes to the high concentration of Mg in the loop of Henle during systemic Mg loading. In another series of young rats (90-160 g), similarly loaded with MgCl2 (UFMg 5.81 meq/liter), Mg and inulin were measured in superficial proximal (PT) and distal tubules (DT). Punctures were paired at two sites of the same PT and DT. The Mg concentration increased progressively along the PT in such a way that 90.5% of the filtered load still remained in the late proximal loops. If superficial and deep proximal tubules behave in a similar manner, it may be concluded that the site of entry of Mg is located between the late accessible part of the PT and the bend of the loop of Henle. Only 58.0 +/- 3.0% of the filtered Mg was delivered to the DT, indicating that Mg is extensively reabsorbed in the ascending limb, despite systemic loading. The proportion of filtered Mg did not vary along the DT, indicating no net reabsorption.     

Relationships between emotional disorders,personality dimensions,and binge eating disorder in French obese adolescents

Purpose

Binge eating disorder (BED) is associated with higher psychopathology, including emotional and personality disorders, in the adult population, whether or not they are obese; although few data are available on adolescents, particularly among obese adolescents.