Recent Publications by CFE Educators

OBJECTIVE

To explore the extent to which sex-specific result (SSR) reporting appears in recently published cardiovascular studies.

METHODS

All original adult cardiovascular clinical trials published in Annals of Internal Medicine, Archives of Internal Medicine, Journal of the American Medical Association, The New England Journal of Medicine, Journal of the American College of Cardiology, The American Journal of Cardiology, and Circulation from July 1 through December 31, 2004, were reviewed. Sex-specific result reporting was defined as presenting primary outcomes for women in a format to allow the data to be abstracted for use in a meta-analysis.

RESULTS

Of the 645 studies reviewed, 17 were excluded because they were appropriately single-sex trials. Of the remaining 628 studies, only 153 (24%) provided SSRs. The percentage of studies reporting SSRs was 37% (23/62) for general medical journals and 23% (130/566) for cardiovascular journals (P = .10). Among National Institutes of Health (NIH)-sponsored research, 31 (51%) of 61 trials analyzed outcomes by sex compared with 125 (22%) of 567 trials not sponsored by the NIH (P .01).

CONCLUSION

Only a few current cardiovascular trials provide sex-specific data. Sex differences remain poorly understood, and this deficiency limits our ability to optimize medical care for both sexes. The stipulation that SSRs be investigated has led to significantly more SSR reporting in NIH-funded research. A parallel mandate by journal editors that requires authors to provide sex-specific data and analysis may help to bridge this knowledge gap.

Aquaporin 1 (AQP1) is the archetypal member of a family of water channel proteins that contribute to water homeostasis in kidney, lung, and other tissues. Although there is limited evidence that aquaporins are expressed in the nervous system, AQP4 is expressed in glia and AQP9 is present on some neuronal and glial mitochondria. In the present study, we used immunohistochemistry to show that AQP1 is heavily expressed in a population of small diameter primary sensory neurons of dorsal root, trigeminal, and nodose ganglia. AQP1 immunoreactivity is abundant in DRG cell bodies and in both the peripheral and central branches of primary afferent neurons, and colocalizes with markers of nociceptors, notably substance P and IB4. AQP1 expression in DRG is first detectable at embryonic day 15.5, which corresponds to the developmental stage when the majority of fine cutaneous afferents penetrate the dorsal horn. Electron microscopy revealed dense membrane labeling of unmyelinated axons, a few fine diameter myelinated axons, and synaptic terminals in the superficial dorsal horn. Because this restricted and dense expression suggested that AQP1 contributes to nociceptive processing, we studied behavioral responses of wildtype and AQP1 -/- mice in a comprehensive battery of acute and persistent pain tests. We also used in vivo electrophysiology in wildtype and mutant mice to measure the responses of wide dynamic range neurons in lamina V of the dorsal horn to thermal stimulation before and after noxious stimulus-induced sensitization. To date we have not detected a differential phenotype suggestive of a functional contribution of AQP1 to nociceptive processing.

BACKGROUND

The failure of skin cancer prevention efforts to alter tanning behaviors may be a result of the addictive nature of UV light.

OBJECTIVE

This study attempts to determine the prevalence of UV light substance-related disorder (SRD).

METHODS

A survey was administered to undergraduate college students. The cut down, annoyed, guilty, eye-opener questionnaire was used to determine existence of SRD.

RESULTS

Of 385 respondents, 12% scored positively on the cut down, annoyed, guilty, eye-opener indicating SRD. Women, indoor tanners, students with tanning family and friends, and frequent tanners were significantly more likely than their peers to score positively.

LIMITATIONS

The small size is a limitation of this study as results may not be generalizable to larger populations. There also may be self-report bias.

CONCLUSIONS

A significant proportion of college students demonstrate evidence of SRD with respect to UV light.

In a previous report, we compared the properties of lamina V neurons of the spinal cord dorsal horn in wild-type mice and in mice with a deletion of the preprotachykinin-A (PPT-A) gene, which encodes substance P (SP) and neurokinin A (NKA). The mutant mice had pronounced deficits in the response to thermal stimulation, both before and after mustard oil induced sensitization. Here, we extended our analysis to the properties of lamina I neurons and also examined responsiveness to mechanical stimulation. Consistent with the properties of lamina V neurons, in the PPT-A mutant mice we found significantly reduced responses of lamina I neurons to noxious thermal stimulation, and mustard oil sensitization of these neurons to heat was lost. In contrast, not only were the responses of lamina I neurons to noxious mechanical stimulation unchanged in the mutant mice, but in neither the wild-type nor the mutant mice could sensitization be induced. However, mustard oil profoundly sensitized lamina V neurons to mechanical stimulation in both wild-type and mutant mice. We conclude that SP and/or NKA are required for the transmission of noxious thermal stimulation by lamina I and V neurons, both before and after tissue injury. The persistence of mechanical sensitization of lamina V neurons in the mutant mice further shows that mustard oil induces mechanical and thermal sensitization through different mechanisms. Finally, we conclude that lamina I sensitization to mechanical stimulation is not required for this form of injury-increased responsiveness of lamina V neurons.