The relationship between head size and intracranial volume in elderly subjects

OBJECTIVE: To study the relationship between parenchymal head volume (PHV) and intracranial volume (ICV), and to compare the ability of these two measurements to reflect the association between maximum mature brain volume and late-life cognition. METHODS: An elderly sample of humans with a range of cognitive functions from normality, via mild cognitive impairment (MCI) to dementia (mean age 78.6, S.D. 2.8; mean MMSE 25.4, S.D. 4.2) was examined. Head-to-head measurements of ICV and parenchymal head volume (PHV) were obtained from three-dimensional T1 weighted magnetic resonance images using automated procedures. Analyses of cognitive functions were based on continuous and categorial variables. RESULTS: PHV explained 55% of the variance in ICV. The ratio between PHV and ICV remained constant with increasing age and cognitive impairment. Measurements of PHV and ICV yielded comparable correlations with global cognitive performance. Group differences over gender and cognitive states were equally present in ICV and PHV. The relative risks of cognitive impairment that were associated with either small ICV or PHV were comparable. CONCLUSIONS: Measures of PHV can be considered as useful estimates of ICV and cerebral volume reserve.     

Refining the linkage analysis on chromosome 10 in 449 sib-pairs with multiple sclerosis

Genome-wide screens for linkage in multiplex families with multiple sclerosis (MS) from United Kingdom, Sardinia, Italy and the Nordic countries (Denmark, Finland, Norway and Sweden) have each shown suggestive or potential linkage on chromosome 10. The partially overlapping regions identified by these studies encompass around 60 cM of the chromosome. In order to explore this region further, we typed 13 microsatellite markers in the same 449 families originally studied in the individual screens. This additional genotyping increased the information extraction in the region from 52% to 79% and revealed increased support for linkage (MLS 2.5) peaking at 10p15.     

Alterations of the immune response with increasing recipient age are associated with reduced long-term organ graft function of rat kidney allografts

BACKGROUND: Clinically, an increasing number of older recipients are listed for transplantation. We examined recipient age-associated alterations of the immune response and their effects on graft function. METHODS: Three- and 18-month-old Lewis (LEW) rats received kidneys from 3- and 18-month-old Fischer 344 (F344) rats (1.5 mg/kg/d cyclosporine A for 10 days; n=6/group) and were observed for 180 days. In additional groups, double kidney transplantations were performed to determine the impact of nephron mass and recipient age on graft outcome. RESULTS: All young recipients but only 66% of old recipients survived the observation period. Increasing recipient age resulted in a significant decrease in renal allograft function (P<0.001), more advanced morphologic evidence of chronic allograft damage (P<0.001), and greater cellular infiltration (P<0.05) and major histocompatibility complex expression (P<0.01) within grafts. Additional in vitro studies examined age-related changes in the cellular immune response by enzyme-linked immunosorbent assay, fluorescence-activated cell sorter analysis, and alloreactive enzyme-linked immunospot: splenocytes from old LEW rats produced significantly more interleukin (IL)-2 (P<0.0001), IL-4 (P<0.05), interferon (IFN)-gamma (P<0.0001), and tumor necrosis factor-alpha (P<0.05). IFN-gamma-producing memory-type T cells were significantly elevated in older rats (P<0.0001). Moreover, they revealed significantly more alloreactive T cells directed against F344 (146 +/- 64.2 and 512 +/- 277/10(6) T cells; P<0.05). Double renal allografts from young donors into old recipients confirmed an independent effect of recipient age on the acceleration of chronic graft deterioration. CONCLUSIONS: The enhanced cellular immune responsiveness in elderly recipients was associated with advanced chronic graft injury. Clinically, older recipients may need a modified immunosuppression.     

Female-condom use in a gender-specific family planning clinic trial

Objectives. We evaluated female-condom use among women participating in an HIV/STD intervention designed to reduce unprotected sex and expand prevention strategies.

Methods. Women (n = 360) were recruited from a family-planning clinic and were randomized into an 8- or 4-session intervention group or a control group. We conducted follow-up interviews at 1, 6, and 12 months.

Results. At 1 month, the odds ratios of first-time female-condom use were 9.49 (95% confidence interval [CI] = 4.01, 22.20) in the 8-session group and 4.39 (95% CI = 1.84, 10.49) in the 4-session group relative to controls. Repeated use (n = 21) was predicted by perceived ability to use, by self and partner satisfaction, by dislike of male condoms, and by previous diaphragm use.

Conclusions. Gender sensitive cognitive-behavioral interventions can influence women to try the female condom. To increase long-term use, interventions may need to include self-insertion practice and involvement of male partners.

     

Feedback strategies to raise awareness of personal dietary intake: results of a randomized controlled trial

BACKGROUND: Feedback is a strategy that can be used to influence awareness of dietary habits. Feedback was applied in an interactive computer-tailored intervention and in printed self-test forms. METHODS: A randomized controlled trial with a 3 (study groups) x 2 (higher vs. medium or lower educational level) design was conducted. Adult subjects (N = 304) were randomly assigned to a feedback group or the control group. Immediate impact on realism of self-rated intake levels of fat, fruit, and vegetables were tested, as were intentions to change. RESULTS: Self-rated fat intake compared to others was more realistic among respondents with a medium or lower educational level in the tailored intervention group. Self-rated fruit intake compared to others was more realistic in the tailored intervention group. Self-rated fat intake was more realistic in the tailored intervention than the self-test group. Intention to reduce fat consumption was greater in the tailored intervention group. Intention to eat more vegetables was greater in the tailored than in the self-test group. Subjects rated the tailored intervention as more effective, more personally relevant, more individualized, and providing more new information. CONCLUSIONS: Only the tailored intervention had an immediate impact on awareness and dietary change intention and was appreciated better than both other interventions.     

Quantitative and qualitative assessment of closed fracture healing using computed tomography and conventional radiography

RATIONALE AND OBJECTIVES: Development of new agents to induce fracture healing requires more sensitive methods to detect early changes in fracture repair. The aims of this study were to determine quantitative and qualitative features of fracture healing using volumetric computed tomography (CT) and to compare them with conventional radiography during the weeks following uncomplicated fractures of the appendicular skeleton. MATERIALS AND METHODS: 39 otherwise healthy men and women with acute, closed fractures of the distal radius, tibial and/or fibular malleoli, or tibial shaft, were enrolled and underwent CT and X-ray imaging at 1, 2, 4, 8, 12, and 16 (tibial shaft only) weeks post fracture. Qualitative assessment included fracture line/margins, fracture gap, external callus appearance, callus-to-cortex ratio, bridging, and radiologic union. Quantitative assessment of CT density changes (Hounsfield units [HU]) in the fracture gap was performed in a subset of 8 fracture patients using MEDx multimodality image analysis software (Sterling,VA). The analysis was performed by drawing free form regions of interest (ROI) covering the fracture gap on baseline (week 1) images and by automated registration of the follow-up images to the baseline co-ordinate system. RESULTS: The mean time to achieve radiologic union on CT was slightly shorter than on X-rays for radial and tibial shaft fractures (7.3 vs. 8.0 weeks, P = .1). Blurring of the fracture margins and reactive sclerosis were the earliest signs of healing in both modalities. External callus formation was evident in 11 cases and was detected earlier with CT technique. Overall, CT images allowed for more complete and detailed visualization of healing compared with conventional X-rays, which were limited by cast and fixation hardware superimposition, especially in subjects with malleolar and distal radial fractures. Quantitative evaluation showed good intraobserver and interobserver reproducibility and a statistically significant correlation to qualitative changes. CONCLUSION: Our methods of fracture healing assessment are reliable tools that are able to detect early changes in normal bone healing and may serve as useful additions to subjective image analysis in monitoring fracture healing in clinical trials. CT shows some advantages over conventional X-rays in evaluation of early fracture healing.