Lipopigment Changes in Purkinje Cells in Alzheimer's Disease.

Cerebellar tissue was examined from 22 patients with Alzheimer's disease (AD) and from an age-matched group of 20 non-diseased subjects. Intraneuronal lipopigment in the bodies of 1344 Purkinje cells (PCs) (32 per brain) was identified by fluorescence microscopy. The mean total area (per PC) of the outlines of discrete regions of lipopigment in a PC perikaryon for the AD-related group of PCs was significantly greater than the mean for the comparison group (p<0.001). Also, the two groups of PCs showed significant (

Alzheimer's disease: distribution of changes in intraneuronal lipopigment in the frontal cortex.

Brains from 22 patients with Alzheimer's disease (AD) and 20 non-diseased subjects were examined. Intraneuronal lipopigment in 2,440 nucleolated neurons throughout the depth of cortex was identified by fluorescence microscopy. In the AD brains, the mean total area per neuron of the outlines of lipopigment was significantly increased in the region adjacent to the brain surface (sixths 1-3), and analysis of variance showed a significant interaction between depth of cortex (in sixths) and AD for this lipopigment variable (p = 0.012). After relating this lipopigment variable to the size of neuronal bodies, the results indicate that this change occurs in pyramidal neurons, although other neuronal types may also be affected. At least one of three AD-related changes in lipopigment was found in each sixth of the depth of cortex.

Effects of chronic chlorpromazine or lithium administration on ageing-related lipopigment in rat Purkinje neurones.

Ageing-related accumulation of neuronal lipopigment is considered to be debris from processes of renewal of cellular constituents, but can also reflect cell damage and certain diseases. Chlorpromazine (an example of a class of drug chronically administered in psychiatric practice) has been reported to reduce neuronal lipopigment accumulation, and the present study investigated the effects of 28 weeks of chlorpromazine administration on lipopigment in rat Purkinje neurones. The effects of 26 weeks of lithium administration (also chronically administered in psychiatric practice) were also studied. Lipopigment was identified by fluorescence microscopy and the area enclosed by an outline of each discrete region of lipopigment was measured. While lithium administration was not associated with significant changes in lipopigment variables, chlorpromazine administration was associated with a significant (p=0.001) reduction in the number of discrete lipopigment regions and with significant (p=0.001) differences in the numbers of discrete lipopigment regions in various size categories. The findings are similar to those associated with the administration of acetyl-L-carnitine (which has been reported to reduce some morphological and behavioural associations of brain ageing) and are compatible with a reduction in the rate of lipopigment formation. This could reflect an adverse effect of chlorpromazine administration (i.e. reduced functional activity of neurones) or a beneficial effect (i.e. a reduction in ageing-related changes).

Changes in intraneuronal lipopigment in Alzheimer's disease.

Brains were examined from 22 patients with Alzheimer's disease (AD) (mean age 80.5, S.D. 11.5) and were compared with brains from 20 nondiseased subjects (mean age 81.1, S.D. 10.2). Intraneuronal lipopigment in all layers of a region of the superior frontal cortex was identified by fluorescence microscopy. The areas enclosed by the outlines of discrete regions of lipopigment autofluorescence were measured and assigned to a range of size categories. AD was associated with significant (p less than 0.05) decreases in the mean number (per neuron) of discrete regions of yellow lipopigment autofluorescence in the three smallest size categories and a significant increase in one of the larger size categories. Also, AD was associated with a significant decrease in the mean number (per neuron) of discrete regions of lipopigment autofluorescence (p less than 0.001). Significant (p less than 0.05) correlations were obtained between the Blessed dementia score (obtained within 2 years of death) and these lipopigment variables. The changes in neuronal lipopigment in AD may reflect an increased rate of lipopigment formation related to membrane and lysosomal abnormalities.

The morphology of lipopigment in rat Purkinje neurons after chronic acetyl-L-carnitine administration: a reduction in aging-related changes.

The aging-related accumulation of neuronal lipopigment is considered to be cellular debris from processes of renewal of cellular constituents, but it can also reflect cell damage and certain diseases. Acetyl-L-carnitine (AC) has been reported to reduce some morphological and behavioral associations of brain aging and the present study investigated the effects of 37 weeks of AC administration on lipopigment in rat Purkinje neurons. Lipopigment was identified by fluorescence microscopy and the area enclosed by an outline of each discrete region of lipopigment was measured. Acetyl-L-carnitine was associated with a significant (p = 0.05) reduction in the number of discrete lipopigment regions and there was a significant (p = 0.001) association of AC administration with numbers of lipopigment regions in various size categories. As AC administration was associated with a reduction in some of the aging-related morphological changes in lipopigment, this compound is a candidate for evaluation as a long-term prophylactic agent for the adverse effects of cerebral aging.

Fungal infections in the acquired immunodeficiency syndrome.

Defects in cell-mediated immunity caused by infection with the human immunodeficiency virus (HIV) render AIDS patients particularly susceptible to fungal pathogens. Signs and symptoms of serious infection may be nonspecific, and early diagnosis and institution of antifungal therapy is essential to decrease morbidity and mortality in this patient population. In a symptomatic individual, invasive procedures are often required to establish a microbiologic diagnosis, and histopathologic examination of tissue by light and electron microscopy is often the first indication of a serious fungal infection in an AIDS patient.