Open-label, short-term, repetitive transcranial magnetic stimulation in patients with Alzheimer's disease with functional imaging correlates and literature review.

BACKGROUND: Accumulating evidence suggests repetitive transcranial magnetic stimulation (rTMS) may be beneficial in ameliorating cognitive deficits in Alzheimer's disease (AD). METHODS: AD patients received four high-frequency rTMS sessions over the bilateral dorsolateral prefrontal cortex (DLPFC) over two weeks. Structured cognitive assessments were administered at baseline, at 2 weeks after completion of rTMS, and at 4 weeks post treatment. At these same times, tolerant patients underwent functional magnetic resonance imaging (fMRI) while performing structured motor and cognitive tasks. We also reviewed literature regarding the effects of rTMS on cognitive function in AD. RESULTS: A total of 12 patients were enrolled, eight of whom tolerated the fMRI. Improvement was seen in Boston Diagnostic Aphasia Examination tests of verbal and non-verbal agility 4 weeks post-treatment. The fMRI analysis showed trends for increased activation during cognitive performance tasks immediately after and at 4 weeks post-treatment. Our literature review revealed several double-blind, sham-controlled studies, all showing sustained improvement in cognition of AD patients with rTMS. CONCLUSIONS: There was improvement in aspects of language after four rTMS treatments, sustained a month after treatment cessation. Our results are consistent with other studies and standardization of treatment protocols using functional imaging may be of benefit.

Current attitudes on self-use and prescription of hormone therapy among New York City gynaecologists.

OBJECTIVE: The results of the Women's Health Initiative studies dramatically altered hormone therapy use around the world. In countries outside the United States, self-use in physicians remained unaltered while prescription use declined, implying that physicians may not concur with the findings. We wished to explore prevailing attitudes among American physicians by examining New York City obstetrician-gynaecologists' self-use and prescription use of hormone therapy. STUDY DESIGN: All board-certified obstetrician-gynaecologists in New York City were invited to complete and return a detailed, previously validated questionnaire concerning hormone therapy use. RESULTS: Two hundred and nine questionnaires were returned, for a response rate of 12% (209/1797). Gynaecologists agreed with the findings from the Women's Health Initiative studies regarding indications and contraindications to hormone therapy use. Even so, three-quarters of female gynaecologists and female partners of male gynaecologists (74%; 67/91) use or have previously used hormone therapy. However, only 27.3% (21/77) of male gynaecologists and 12.3% (14/114) of female gynaecologists recommend hormone therapy to all menopausal women regardless of contraindications. Gynaecologists remain divided in their attitude toward hormone therapy; 30% of gynaecologists felt that hormone therapy use generally prolonged women's lives, 36% felt it was not useful in prolonging women's lives, and 33% were unsure. CONCLUSION: Since the publication of the Women's Health Initiative findings, New York City gynaecologists prescribe hormone therapy to fewer patients. However, they continue to self-use hormone therapy at much higher rates, even as they seem to concur with Women's Health Initiative recommendations, contributing to the ongoing controversy surrounding the validity of the Women's Health Initiative findings.

Functionally compensating coevolving positions are neither homoplasic nor conserved in clades.

We demonstrated that a pair of positions in phosphoglycerate kinase that score highly by three nonparametric covariation measures are important for function even though the positions can be occupied by aliphatic, aromatic, or charged residues. Examination of these pairs suggested that the majority of the covariation scores could be explained by within-clade conservation. However, an analysis of diversity showed that the conservation within clades of covarying pairs was indistinguishable from pairs of positions that do not covary, thus ruling out both clade conservation and extensive homoplasy as means to identify covarying positions. Mutagenesis showed that the residues in the covarying pair were epistatic, with the type of epistasis being dependent on the initial pair. The results show that nonconserved covarying positions that affect protein function can be identified with high precision.

Circadian clock feedback cycle through NAMPT-mediated NAD+ biosynthesis.

The circadian clock is encoded by a transcription-translation feedback loop that synchronizes behavior and metabolism with the light-dark cycle. Here we report that both the rate-limiting enzyme in mammalian nicotinamide adenine dinucleotide (NAD+) biosynthesis, nicotinamide phosphoribosyltransferase (NAMPT), and levels of NAD+ display circadian oscillations that are regulated by the core clock machinery in mice. Inhibition of NAMPT promotes oscillation of the clock gene Per2 by releasing CLOCK:BMAL1 from suppression by SIRT1. In turn, the circadian transcription factor CLOCK binds to and up-regulates Nampt, thus completing a feedback loop involving NAMPT/NAD+ and SIRT1/CLOCK:BMAL1.