Cerebellar Purkinje cells (PCs), the sole output neurons in the cerebellar cortex, play an important role in the cerebellar circuit. PCs appear to be rather sensitive to aging, exhibiting significant changes in both morphology and function during senescence. This article reviews such changes during the normal aging process, including a decrease in the quantity of cells, atrophy in the soma, retraction in the dendritic arborizations, degeneration in the subcellular organelles, a decline in synapse density, disorder in the neurotransmitter system, and alterations in electrophysiological properties. Although these deteriorative changes occur during aging, compensatory mechanisms exist to counteract the impairments in the aging PCs. The possible neural mechanisms underlying these changes and potential preventive treatments are discussed.

ObjectiveTo carry out a cross-sectional study of 187 cognitively normal Chinese adults using the voxel-based morphometry (VBM) approach to delineate age-related changes in the white matter volume of regions of interest in the brain and further analyze their correlation with age.Materials and methodsA total of 187 cognitively normal adults were divided into the young, middle, and old age-groups. Conventional magnetic resonance imaging was performed with the Achieva 3.0 T system. Structural images were processed using VBM8 and statistical parametric mapping 8. Regions of interest were obtained by WFU PickAtlas, and all realigned images were spatially normalized.ResultsFemales showed significantly greater total white matter volume than males (t=2.36, P=0.0096, false-discovery rate [FDR] corrected). VBM demonstrated statistically significant age-related differences in white matter volume between the young age-group and the middle age-group (P<0.05, FDR corrected) and between the middle age-group and the old age-group (P<0.05, FDR corrected). No interaction was found between age and sex on white matter volume (P<0.05, FDR corrected). Logistic regression analysis revealed nonlinear correlation between total white matter volume and age (R2=0.124, P<0.001). White matter volume gradually increased before 40 years of age, peaked around 50 years of age, and rapidly declined after 60 years of age.ConclusionSignificant age-related differences are present in white matter volume across multiple brain regions during aging. The VBM approach may help differentiate underlying normal neurobiological aging changes of specific brain regions from neurodegenerative impairments.

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Hypoeutectic Zn-4.45 wt% Al solidified under a high magnetic field was investigated crystallographically. With the field, the primary zinc-rich phase is distributed homogeneously and orients with the c axis perpendicular to the magnetic field direction. These results are attributed to the magnetic viscosity resistance force and the magnetocrystalline anisotropy of zinc, respectively. The orientation modification also leads to a preferential alignment of the flat-shaped primary dendrites. Furthermore, with the field, the eutectic phase shows an orientation character similar to that of the primary phase. This arises from its continuous growth with the primary phase. In addition, a specific crystallographic orientation relationship ({0001} || {111} , h1210i || h110i ) exists in some of the eutectics (between the eutectic zinc-rich and aluminium-rich phases). However, this orientation relationship is related to the distribution of primary dendrites, which originates from the independent nucleation of the pseudo-primary phase attached to the primary dendrites.

Significant age-related differences are present in gray matter volume across multiple brain regions during aging. The VPM approach may provide an emerging paradigm in the normal aging brain that may help differentiate underlying normal neurobiological aging changes of specific brain regions from neurodegenerative impairments.

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AbstractObjectiveThe aim of this study was to investigate the correlation of von Hippel-Lindau tumor suppressor (VHL) mRNA expression and jade family PHD finger 1 (Jade-1) gene expression in patients with renal cell carcinoma (RCC). Another aim of this study was to analyze the relationship of these two genes with clinicalpathological features of the RCC patients. Methods: A total of 75 RCC patients who received surgically therapy in our hospital were included. All patients had complete pathological data. The expression of VHL/Jade-1 was determined by real-time polymerase chain reaction (RT-PCR). Results: VHL and Jade-1 were both obviously downregulated in RCC tissues than that of the matched normal tissues, and both negatively correlated with tumor size as well as tumor grade. And we found a fine association of VHL gene expression with Jade-1. Conclusion: VHL/Jade-1 exhibited significantly decreased expression in RCC tissues and was closely related to the clinical prognosis of patients. The finding of VHL expression positively correlated with Jade-1 expression shed light and provided crucial evidence on the connection of VHL protein with Wnt/b-catenin pathway.

Grain refinement of a magnesium alloy, AZ80, was studied in multi-directional forging (MDF) with decreasing temperatures from 683 to 573 K. The MDF was carried out up to accumulative true strains of around 7 with changing the loading direction from pass to pass. The structural changes are characterized by the alternate appearance of fine dynamic recrystallized (DRXed) grains (with many dynamic granular Mg 17 Al 12 phases) and coarse DRXed grains (without Mg 17 Al 12 phases) in the sample, the expansion of the fine grains area, and the refinement of (DRXed) grains in the fine grains area during the MDF process. The non-uniform dynamic precipitation of the Mg 17 Al 12 phase may attribute to the inhomogenous Al content distribution in the Mg matrix. These Mg 17 Al 12 phase retards the growth of the DRX grains, which in turn results in the formation and the expansion of the fine grains area during the MDF process with decreasing temperature.