Oxygenation in cervical cancer and normal uterine cervix assessed using blood oxygenation level‐dependent (BOLD) MRI at 3T

Hypoxia is reported to be a biomarker for poor prognosis in cervical cancer. However, a practical noninvasive method is needed for the routine clinical evaluation of tumor hypoxia. This study examined the potential use of blood oxygenation level‐dependent (BOLD) contrast MRI as a noninvasive technique to assess tumor vascular oxygenation at 3T. Following Institutional Review Board‐approved informed consent and in compliance with the Health Insurance Portability and Accountability Act, successful results were achieved in nine patients with locally advanced cervical cancer [International Federation of Gynecology and Obstetrics (FIGO) stage IIA to IVA] and three normal volunteers. In the first four patients, dynamic T₂*‐weighted MRI was performed in the transaxial plane using a multi‐shot echo planar imaging sequence whilst patients breathed room air followed by oxygen (15 dm³/min). Later, a multi‐echo gradient echo examination was added to provide quantitative R₂* measurements. The baseline T₂*‐weighted signal intensity was quite stable, but increased to various extents in tumors on initiation of oxygen breathing. The signal in normal uterus increased significantly, whereas that in the iliacus muscle did not change. R₂* responded significantly in healthy uterus, cervix and eight cervical tumors. This preliminary study demonstrates that BOLD MRI of cervical cancer at 3T is feasible. However, more patients must be evaluated and followed clinically before any prognostic value can be determined. Copyright © 2012 John Wiley & Sons, Ltd.     

Investigation of a neuropsychological screen for chemo-fog

Research on chemotherapy-induced cognitive impairment (the term “chemo-fog” is used by many investigators) supports the occurrence of subtle declines in function for a subset of recipients. Identification of vulnerable individuals via comprehensive neuropsychological batteries is complicated due to their lack of clinical utility and increased risk of misclassification. The goal of this paper was to evaluate the ability of a reduced battery to detect chemotherapy-related cognitive impairments. Data from our previous study (Ouimet et al. J Clin Exp Neuropsychol 31:73–89, 2009) were used to compare a comprehensive neuropsychological test battery comprising 23 tests with a reduced battery consisting of a subset of nine tests. A standardized regression-based approach revealed that a comparable numbers of participants were identified by both batteries, suggesting that individuals vulnerable to chemotherapy-induced cognitive impairment can be identified by a more selective battery. Further work is needed to clarify the neuropsychological tests most sensitive to detecting impairments associated with chemotherapy so that assessment batteries can be limited to these tests.     

Systematic quantification of histologic ventricular fibrosis in isolated mitral valve prolapse and sudden cardiac death

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Blood meal size as a factor affecting continued host-seeking by Aedes aegypti (L.)

The effect of ingested blood on the host-seeking response of two strains of Aedes aegypti was examined. Using an olfactometer, females fed partial blood meals were scored for host-seeking behavior within 1 h, and their blood meal sizes were measured chemically immediately afterwards. The suppression of host-seeking within 1 h after a blood meal appears to be caused by abdominal distention from ingested blood. Mosquitoes of either strain were attracted to a host when the blood meal size was less than 2.5 microliter; above this threshold there was a sharp decline in the tendency to respond. Small mosquitoes resulting from a low larval diet had a lower threshold, and were more likely to cease host-seeking after a small blood meal. Multiple feeding within a single gonotrophic cycle may result if mosquitoes take small blood meals which are insufficient to terminate host-seeking. Partial meals and reduced feeding success of mosquitoes can result from defensive host behavior, which in the laboratory rat was shown to increase at high mosquito densities.