T2 values in the human brain: comparison with quantitative assays of iron and ferritin

Magnetic resonance (MR) imaging with a whole-body imager was performed in 10 fresh, unfixed whole human brains selected randomly from cadavers. All subjects were neurologically intact before death. T2 time constants were measured within the caudate nucleus, putamen, globus pallidus, cortical gray matter, subcortical white matter, and optic radiation. These regions were then excised, and T2 values were measured again with a 1.5-T MR spectrometer. Quantitative assays of iron, ferritin, and protein from these areas were then performed. Iron concentration varied significantly among brain regions, whereas ferritin and protein concentrations were constant among brain regions and among individuals. Neither iron nor ferritin concentration showed any consistent correlation with T2 values. Histologic examination of brain micro-sections with iron- and ferritin-specific stains of demonstrated poor correlation with biochemical assays of ferritin and iron concentrations. Results indicate that T2 values correlate poorly with iron and ferritin concentrations found in neurologically intact brains.     

The preliminary study on HMBA-induced differentiation of the drug-pretreated murine erythroleukemia cells

Several drug-resistant variants have been developed by growing the parental MEL cells in presence of colchicine, adriamycin and vincristine respectively with stepwise increasing concentration. Both the colchicine-resistant Sc9(Co10) and vincristine-resistant Sc9(VCR5) cells displayed an accelerated HMBA-induced commitment to terminal cell differentiation, whereas the adriamycin-resistant SC9 (A120) showed no acceleration but rather a substantial delay in HMBA-induced differentiation. The studies provide more clues as well as experimental models for further study on the mechanism of induced differentiation of MEL cells.     

A role for the primary care physician in counseling young African-American men about homicide prevention

Homicide is the leading cause of death in African-American men aged 15–34 years, yet physicians rarely discuss homicide prevention with patients. The authors propose that physicians have a role in preventing homicide similar to their role in other preventive medicine issues. This study evaluated patients’ responsiveness to a physician’s counseling about firearms and homicide. While being treated for unrelated problems at a walk-in ambulatory clinic, 53 African-American men patients received brief counseling by the physician about six preventive medicine topics, including firearms. A postvisit interview demonstrated that the discussion of firearms was well received and recalled more than any other preventive medicine issue discussed.     

High-Strength Tretinoin for Rapid Retinization of Photoaged Facial Skin

Background. Emollient creams of 0.02% and 0.05% tretinoin are currently used for improving the appearance of photoaged skin. At these concentrations, using this vehicle, the clinical results take many months.
Objective. The objective was to formulate and test a higher strength tretinoin that enhances penetration of the active molecule through the stratum corneum so that the clinical result is achieved after 1 month of treatment.
Methods. Thirty-two female subjects underwent treatment with 0.25% tretinoin solution applied nightly for 1 month. Subjects were evaluated clinically at baseline and 1, 2, and 4 weeks. Clinical grading was performed by comparing digital photographs before and after treatment.
Results. Almost all subjects improved on all measures of clinical grading (fine lines, mottled pigmentation, surface texture/roughness) by the end of the study.
Conclusion. Tretinoin solution at a concentration of 0.25% is an effective and tolerable treatment for photodamaged facial skin and greatly shortens the time required for clinical response.