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A cohort of morphologically heterogenous doublecortin immunoreactive (DCX+) “immature neurons” has been identified in the cerebral cortex largely around layer II and the amygdala largely in the paralaminar nucleus (PLN) among various mammals. To gain a wide spatiotemporal view on these neurons in humans, we examined layer II and amygdalar DCX + neurons in the brains of infants to 100 year-old individuals. Layer II DCX + neurons occurred throughout the cerebrum in the infants/toddlers, mainly in the temporal lobe in the adolescents and adults, and only in the temporal cortex surrounding the amygdala in the elderly. Amygdalar DCX + neurons occurred in all age groups, localized primarily to the PLN, and reduced in number with age. The small-sized DCX + neurons were unipolar or bipolar, and formed migratory chains extending tangentially, obliquely and inwardly in layers I-III in the cortex, and from the PLN to other nuclei in the amygdala. Morphologically mature-looking neurons were lightly labeled and co-expressed the neuron-specific nuclear antigen, glutamic acid decarboxylase and nicotinamide adenine dinucleotide phosphate-diaphorase. Taken together, we consider that the layer II and amygdalar DCX + neurons form a slowly developing interneuron system that supports inhibitory network plasticity in the cerebrum in an age/region-dependent manner.

β-Amyloid (Aβ) deposition is a commonly studied neuropathology in the human brain, occurring as compact and diffuse parenchymal plaques, cerebral amyloid angiopathy (CAA), and meningeal/subpial amyloidosis. Compact plaques associated with dystrophic neurites generally referred to as neuritic plaques, are a pathological hallmark of Alzheimer's disease (AD). We evaluated three recently developed monoclonal mouse antibodies against Aβ (A1, A2 and A3) using appropriate tissue samples and assay controls in the present study. In immunohistochemistry, antibodies A1, A2 and A3 displayed all forms of cerebral Aβ deposition in a range of dilutions in cryostat and paraffin sections. These labeled profiles appeared morphologically comparable to that visualized by two commercial Aβ antibody clones, 6E10 and D12B2. In immune-dot blotting assays, antibodies A1, A2 and A3 at highly diluted concentrations detected an increase of Aβ in neocortical lysates of AD samples compared to control. Moreover, these antibodies clearly labeled Aβ pathology in brain sections of three commonly used transgenic mouse models of AD, namely, APP/PS1 mice, 5XFAD mice, and 3XTg-AD mice. Taken together, these monoclonal mouse anti-Aβ antibodies can serve as new experimental tools for basic, translational, and diagnostic research into aging and AD-related cerebral Aβ neuropathology in both human and experimental animal brains.

Airborne particulates (PM2.5 and TSP) were collected from outdoor and indoor areas at urban (Haizhu District) and suburban (Huadu District) sites from 2019 to 2020 in Guangzhou. Three nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) in the airborne particulates were identified by a gas chromatograph equipped with a triple-quadrupole mass spectrometer. In the Haizhu District and Huadu District, the nitro-PAH concentrations in PM2.5 and TSP did not show a significant decrease from winter to summer. From 2019 to 2020, the difference in the average concentration of nitro-PAHs in PM2.5 and TSP in Guangzhou was relatively low and had no statistical significance. The diagnostic ratios of 2-nitrofluorene (2-NF)/1-nitropyrene (1-NP) in TSP are less than five, while for 2-NF/1-NP in outdoor PM2.5 in the summer of 2019 and 2020 are more than five, which indicates that nitro-PAHs in the atmospheric PM2.5 in Guangzhou during summer mainly originated from the secondary formation of atmospheric photochemical reactions between parent PAHs and oxidants (·OH, NO3, and O3). 9-Nitroanthracene (9-NT) made the most significant contribution to the total nitro-PAH concentration. The incremental lifetime cancer risks (ILCRs) of nitro-PAHs in PM2.5 and TSP by inhalation exposure indicated low potential health risks in the urban-suburban of Guangzhou.

Chirality has been proved to play a significant role in tuning cell behaviors and controlling cellular functions. Up to now, almost all the chirality origins of extracellular microenvironment are belong to chiral ligands induction or direct chiral patterns. In this study, chiral gold nanoclusters (L/D-AuNC) loaded on two-dimensional gold nanoparticle films (L/D-film) with multiple chirality origins were prepared to regulate the adhesion and differentiation of mouse bone marrow mesenchymal stem cells (MSCs). MSCs on the D-film exhibited higher cell density and larger spreading area, and more cells differentiated into osteoblasts. Compared with D-film, L-film has a lower cell density and smaller spreading area, and more adipoblasts are achieved. The corresponding expression results of osteogenic differentiation marker (RUNX2) also confirmed the above experimental phenomenon. These results demonstrated that the chirality of clusters has great effect on the direction of cell fate.

The direct radiative capture process is well described by the spherical potential model. In order for the model to explain direct captures more accurately, the effect of the nuclear deformation has been added and analyzed in this work, since most nucleuses are not spherical. The results imply that the nuclear deformation largely affects the direct capture and should be taken into account during discussing direct capture reactions., 5 pages, 3 figures