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J Fowler

Publications and source records attributed to J Fowler.

159 records · Page 9Linked to original sources
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Positron emission tomography studies of normal aging: a replication of PET III and 18-FDG using PET VI and 11-CDG.

Using PET VI and 11-CDG we replicated our earlier PET III and 18-FDG normal aging findings. Examination of young and old normal volunteers revealed the absence of any absolute regional age-related changes in glucose utilization. For the combined sample (N = 81) we did find evidence to suggest a relative hypofrontal change with increasing age. A strong relationship between age and ventricular size (CT) was also found. These findings suggest the preserved glucose metabolism of the resting aging brain in the presence of structural atrophic changes.

Adult↗
PubMedDate not supplied

Hippocampal formation glucose metabolism and volume losses in MCI and AD.

We used MRI volume sampling with coregistered and atrophy corrected FDG-PET scans to test three hypotheses: 1) hippocampal formation measures are superior to temporal neocortical measures in the discrimination of normal (NL) and mild cognitive impairment (MCI); 2) neocortical measures are most useful in the separation of Alzheimer disease (AD) from NL or MCI; 3) measures of PET glucose metabolism (MRglu) have greater diagnostic sensitivity than MRI volume. Three groups of age, education, and gender matched NL, MCI, and AD subjects were studied. The results supported the hypotheses: 1) entorhinal cortex MRglu and hippocampal volume were most accurate in classifying NL and MCI; 2) both imaging modalities identified the temporal neocortex as best separating MCI and AD, whereas widespread changes accurately classified NL and AD; 3) In most between group comparisons regional MRglu measures were diagnostically superior to volume measures. These cross-sectional data show that in MCI hippocampal formation changes exist without significant neocortical changes. Neocortical changes best characterize AD. In both MCI and AD, metabolism reductions exceed volume losses.

Aged↗
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The effects of dietary fibre on upper and lower gastro-intestinal transit times and faecal bulking.

A total of 10 obese patients (body mass index greater than 25) undergoing treatment with a very low-calorie (330 kcal/day) liquid diet were treated without and with 10.5 or 21 g/day dietary fibre. Mean (+/- SE) faecal bulking increased significantly (P less than 0.001) in a dose-dependent manner from 314.8 +/- 54.4 g on a fibre-free diet to 517.2 +/- 45.4 g and 748.9 +/- 78.5 g, respectively, over 5 days on diets containing 10.5 and 21 g/day dietary fibre. Total mean colonic transit time decreased from 53.9 +/- 3.6 h on a fibre-free diet to 25.8 +/- 44 and 17.3 +/- 4.6 h, respectively, on diets including 10.5 and 21 g/day dietary fibre. Both right and left colonic transit times were similarly affected but no effect on orocaecal transit time was detected.

Body Mass Index↗
PubMedDate not supplied

The preclinical assessment of the risk for QT interval prolongation.

Some drugs have been reported to induce severe ventricular arrhythmias, including torsades de pointes, and have been responsible in some cases for sudden death of patients. Although the mechanisms of these arrhythmias are not well understood, they are often, but not always, associated with QT interval prolongation. Regulatory authorities (CPMP in Europe) have recently pointed out the necessity to assess most carefully the potential, especially of non-cardiovascular drugs, for QT interval prolongation. Different methodological approaches are presented in this paper and experimental protocols are suggested; limitations and advantages of the presently available in vitro and in vivo models are discussed. It appears that both in vitro and in vivo approaches are complementary. In particular it is pointed out that only the in vitro models using isolated cardiac tissues (Purkinje fibres or papillary muscles) enable assessment of the drug properties under low cardiac rhythm conditions. This model allows us to mimic pathological situations of long QT interval (such as acquired or congenital long QT syndrome) in which most of the major clinical problems are encountered. Finally, a strategy for the preclinical assessment of the potential of a molecule for QT interval prolongation is presented.

Animals↗
PubMedDate not supplied

Age does not influence DNA fragmentation in the hippocampus after fatal traumatic brain injury in young and aged humans compared with controls.

Paraffin sections from the hippocampus of 12 head-injured patients (Group A, aged between 4 and 12 years n = 6 and Group B, aged between 64 and 89 years n = 6) and associated age-matched controls were stained by the terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphate nick end labeling (TUNEL) technique for evidence of in-situ DNA fragmentation. TUNEL+ cells were of 2 Types: I (non-apoptotic) and II (apoptotic). In addition sections stained H&E, combined Luxol Fast Blue/Cresyl Violet and by immunohistochemistry for astrocytes (GFAP) and macrophages (CD68) were used to characterize the lesions. Small numbers of Type I TUNEL+ cells were seen in all sectors of the hippocampus except CA2 of both Groups A and B. Type II TUNEL+ cells were mainly found in the white matter. They constituted less than 1% of all TUNEL+ cells. There were similar or fewer TUNEL+ cells in the corresponding areas in the controls compared with the head-injured patients. However, in the dentate fascia and the CA4 sector of the Group B cases, larger numbers of TUNEL+ cells were seen in controls than after trauma. In the grey matter most TUNEL+ cells had the morphology ofnecrosis that corresponded with foci of selective neuronal damage. Only a few TUNEL+ cells were seen in white matter. The occasional Type I TUNEL+ cells were seen in grey matter. It is concluded that the amount and distribution of DNA fragmentation in children and adults is similar and therefore at least in the hippocampus does not provide an explanation for age as an independent variable of outcome after traumatic brain injury in childhood.

Age Factors↗
PubMedDate not supplied

A comparison of two commercially irradiated Trypticase Soy Agars containing lecithin and polysorbate 80.

Gamma-radiation sterilized Trypticase Soy Agar containing lecithin and polysorbate 80 (TSA++) (Becton Dickinson Microbiology Systems, Cockeysville, MD) and irradiated TSA++ (Adams Scientific, West Warwick, RI) were tested by a quantitative spread plate method. Four bacteria Bacillus subtilis ATCC 6633, Pseudomonas aeruginosa ATCC 10145, Staphylococcus aureus ATCC 25923, Streptococcus pyogenes ATCC 19615 and the yeast Candida albicans ATCC 10231 were tested in two separate experiments using different lots of media. A strain of Aspergillus niger ATCC 16404, was tested by a qualitative streak plate method. The Becton Dickinson Microbiology Systems (BDMS) irradiated TSA++ overall recovered a greater number of organisms than the Adams Scientific TSA++ in both experiments and allowed for the earlier recovery of S. pyogenes ATCC 19615. The growth of A. niger ATCC 16404, was comparable on both media. Efficacy of the media to neutralize 1, 2 and 3% phenol as well as 0.001, 0.01 and 0.1% benzalkonium chloride (BC) solutions was done by a disk diffusion method using 2 gram-positive and 4 gram-negative bacteria. Both media showed complete neutralization of the 0.001 and 0.01% BC solutions and partial neutralization of the 0.1% BC solution. The BDMS TSA++ showed better neutralization of the 2 and 3% phenol solutions than the Adams Scientific TSA++. This data indicates that not all irradiated TSA++ media perform in an equivalent manner.

Agar↗
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A game of patients.

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Adolescent↗
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Nurses' perceptions of the elements of good supervision.

This paper explores the concept of good clinical supervision from the perspective of the nurse being supervised. A focused discussion with a group being supervised was used to develop a questionnaire, which was then given to 50 post-registration students who were receiving formal clinical supervision (seven students were on the ENB higher award and 43 were on ENB clinical award courses). A number of characteristics of good supervision were identified. These were grouped into one of three themes: relevant knowledge, supervisory/teaching skills and personal relationship skills. This paper is part of a larger study that aimed to explore the concept of good clinical supervision from the perspectives of the supervisor, the person being supervised, the professional bodies and nursing lecturers.

Attitude↗