Characterization of spastic paraplegia in a family with a novel PSEN1 mutation

Spastic paraparesis has been described to occur in 13.7% of PSEN1 mutations and can be the presenting feature in 7.5%. In this paper, we describe a family with a particularly young onset of spastic paraparesis due to a novel mutation in PSEN1 (F388S). Three affected brothers underwent comprehensive imaging protocols, two underwent ophthalmological evaluations and one underwent neuropathological examination after his death at age 29. Age of onset was consistently at age 23 with spastic paraparesis, dysarthria and bradyphrenia. Pseudobulbar affect followed with progressive gait problems leading to loss of ambulation in the late 20s. Cerebrospinal fluid levels of amyloid-β, tau and phosphorylated tau and florbetaben PET were consistent with Alzheimer's disease. Flortaucipir PET showed an uptake pattern atypical for Alzheimer's disease, with disproportionate signal in posterior brain areas. Diffusion tensor imaging showed decreased mean diffusivity in widespread areas of white matter but particularly in areas underlying the peri-Rolandic cortex and in the corticospinal tracts. These changes were more severe than those found in carriers of another PSEN1 mutation, which can cause spastic paraparesis at a later age (A431E), which were in turn more severe than among persons carrying autosomal dominant Alzheimer's disease mutations not causing spastic paraparesis. Neuropathological examination confirmed the presence of cotton wool plaques previously described in association with spastic parapresis and pallor and microgliosis in the corticospinal tract with severe amyloid-β pathology in motor cortex but without unequivocal disproportionate neuronal loss or tau pathology. In vitro modelling of the effects of the mutation demonstrated increased production of longer length amyloid-β peptides relative to shorter that predicted the young age of onset. In this paper, we provide imaging and neuropathological characterization of an extreme form of spastic paraparesis occurring in association with autosomal dominant Alzheimer's disease, demonstrating robust diffusion and pathological abnormalities in white matter. That the amyloid-β profiles produced predicted the young age of onset suggests an amyloid-driven aetiology though the link between this and the white matter pathology remains undefined.

Effectiveness of transdermal nicotine patch in premenopausal female smokers is moderated by within-subject severity of negative affect and physical symptoms

RATIONALE

Nicotine patches may be less effective in female compared with male smokers. However, it is unknown if negative affect and physical symptoms influence transdermal nicotine patch-related effects on smoking behaviors.

METHODS

Eighty-one acutely tobacco-abstinent premenopausal female smokers attended three counter-balanced experimental sessions across the menstrual cycle (early follicular, late follicular, and mid-luteal) and were randomized to patch condition (nicotine [21 mg] vs. placebo [0 mg] transdermal patch). Negative affect and physical symptoms were assessed prior to patch administration. The patch was removed 5 h post-administration, and participants completed a smoking reinstatement task. Multilevel linear models tested associations of patch condition, negative affect and physical symptoms, and their interaction on smoking behavior.

RESULTS

There was a significant patch condition × Negative Affect and Pain symptoms interaction on the number of cigarettes smoked (p < 0.05). When Negative Affect and Pain were lower-than-usual, females administered a nicotine patch smoked significantly fewer cigarettes than females administered a placebo patch (p < .05), but there were no significant patch differences when Negative Affect and Pain were higher-than-usual. There was also a significant patch condition × Negative Affect interaction on time delay. The effects of patch condition on time delay to smoking were greater during sessions in which Negative Affect was higher-than-usual.

CONCLUSIONS

Results suggest that among female smokers transdermal nicotine patch effectiveness may interact with negative affect and pain. Understanding and considering female-specific factors that may impact the efficacy of one of the most commonly used cessation medications is important for improving smoking cessation in female smokers.