Heterogenous Subtypes of Late-Life Depression and Their Cognitive Patterns: A Latent Class Analysis.

Background: Late-life depression (LLD), characterized by cognitive deficits, is considered heterogeneous across individuals. Previous studies have identified subtypes with diverse symptom profiles, but their cognitive patterns are unknown. This study aimed to investigate the subtypes of LLD and the cognitive profile of each group.

Comparison of Quantitative Electroencephalogram During Sleep in Depressed and Non-Depressed Patients with Parkinson's Disease.

BACKGROUND Depression is one of the most important factors affecting quality of life in Parkinson's patients. Most research on Parkinson's disease with depression has focused on neuroimaging, and there have been few quantitative electroencephalogram studies. Sleep is a biomarker for depression; therefore, the aim of this study was to identify differences in quantitative electroencephalograms during sleep in depressed and non-depressed patients with Parkinson's disease.

Microglial activation and age-related dopaminergic neurodegeneration in MPTP-treated SAMP8 mice.

Senescence-accelerated mouse prone 8 (SAMP8) has an early onset of senility and a shorter life span, providing with cognitive impairment. Contrasted with C57BL/6 mouse, which is most commonly used in the study of Parkinson's disease (PD), SAMP8 needs shorter period of breeding and might be good candidate for the investigation of cognitive impairment in PD. Studies had shown the increase of sensibility to 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) with aging in C57BL/6 mouse.

[Neurotoxicity effect of MPP+ on primary cultured mesencephalon neurons of SAMP8 mouse].

Aim: To investigate the effect of MPP+ on the midbrain neurons of SAMP8 mouse in vitro, which provide the cell model for PD study.

Methods: SAMP8 mouse primary midbrain cell cultures were obtained from mice within 1 day after birth. On the sixth day after culturing, the cultures were treated with 100 micromol/L of MPP+ for 6 hours, 9 hours, 12 hours and 24 hours, then the cells were fixed and followed by immunofluorescence or Western blot analysis for the expressed location and the level of TH respectively.