A variant of Alzheimer's disease with spastic paraparesis and unusual plaques due to deletion of exon 9 of presenilin 1.

We describe a novel variant of Alzheimer's disease (AD) in a Finnish pedigree with 17 affected individuals of both sexes in three generations. The disease is characterized by progressive dementia which is, in most cases, preceded by spastic paraparesis. Neuropathological investigations revealed numerous, distinct, large, round and eosinophilic plaques as well as neurofibrillary tangles and amyloid angiopathy throughout the cerebral cortex. The predominant plaques resembled cotton wool balls and were immunoreactive for Abeta but lacked a congophilic dense core or marked plaque-related neuritic pathology. Molecular genetic analysis revealed that the disease was caused by a deletion of exon 9 (delta9) of the presenilin 1 (PS1) gene from the mRNA: unlike previous examples of the delta9 variant, the deletion was not caused by a splice acceptor site mutation.

The magnitude of blood lactate increases from high speed workouts.

To examine blood lactate concentrations from high-speed exercise resistive exercise, subjects performed workouts on an inertial kinetic exercise (Oconomowoc, WI) device. Workouts entailed two 60-s sets of elbow flexor (curling) repetitions. Pre- and post-exercise blood lactate concentrations were measured, via a fingertip blood drop, with an analyzer. From workouts the average acceleration, maximum force and total torque were derived. Blood lactate concentrations were analyzed with a 2 (gender)×2 (time) ANOVA, with repeated measures for time. Average acceleration, maximum force and total torque were analyzed with one-way (gender) ANOVAs. With an α=0.05, blood lactate concentrations had a time (prewomen) effects. Current blood lactate concentrations were commensurate with other studies that used a modest level of resistance and engaged a small muscle mass. Given the current workout protocol and muscle mass engaged, as well as parallels to other results, our study appears to offer a valid portrayal of subsequent changes in blood lactate concentrations from high-speed resistive exercise.

The effects of benomyl and its breakdown products carbendazim and butyl isocyanate on the structure and function of tracheal ciliated cells.

The effects of the fungicide benomyl and its breakdown products, carbendazim and butyl isocyanate, were examined on canine tracheal epithelial tissue in primary culture. Changes in ciliary frequencies were monitored with an optical spectrum analysis system. Serial dilutions of the test compounds were prepared in 100% corn oil and applied to the cell cultures for intervals up to 6 hours and frequencies measured at intervals of 15 minutes to 1 hour. Benomyl and butyl isocyanate caused concentration-dependent decreases in ciliary beat frequency. Benomyl at 300 micrograms/ml (3 mM) caused ciliostasis within 75 minutes of exposure. Butyl isocyanate at a molar concentration three times lower than benomyl (1 mM) caused a similar response, although within 30 minutes. The IBC50 for benomyl was 0.75 mM, while for butyl isocyanate it was 0.52 mM. Carbendazim caused a moderate decrease in frequency over a 6 hour exposure period. Benomyl caused moderate to severe swelling of the mitochondria of ciliated epithelial cells with other cell organelles appearing normal. Butyl isocyanate did not cause any noticeable effect on cell ultrastructure and the apparently low rate of penetration of carbendazim into cells made it impossible to obtain an effect which justified ultrastructural analysis. It appears, at least for benomyl and butyl isocyanate, that while the physiological effect of these two compounds (inhibition of ciliary beat) is the same, the sites of action in the cell may be different.

Localization of frontotemporal dementia with parkinsonism in an Australian kindred to chromosome 17q21-22.

An Australian family with autosomal dominant presenile nonspecific dementia was recently described. The disease results in behavioral changes, usually disinhibition, followed by the onset of dementia accompanied occasionally by parkinsonism. Twenty-eight affected individuals were identified with an age of onset of 39 to 66 years (mean, 53 +/- 8.9 years). We mapped the disease locus to an approximately 26-cM region of chromosome 17q21-22 with a maximum two-point LOD score of 2.87. Affected individuals share a common haplotype between markers D17S783 and D17S808. This region of chromosome 17 contains the loci for several neurodegenerative diseases that lack distinctive pathological features, suggesting that these dementias, collectively referred to as frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17), are caused by mutations in the same gene. The entire coding region of five genes, mapped to the FTDP-17 candidate region, were also sequenced. This analysis included the microtubule-associated protein tau that is the major component of the paired helical filaments observed in Alzheimer's disease. No pathogenic mutations were identified in either the tau gene or in any of the other genes analyzed.