Many studies have shown that solving addition and subtraction problems can induce overt shifts of spatial attention. In particular, right-side targets are detected faster than left-side targets when preceded by an addition operation, while left-side targets are detected faster than right-side targets when preceded by a subtraction operation. However, the interaction between space and arithmetic in multiplication or division is hardly studied and remains controversial. In order to make a strong case for the interaction between space and mental arithmetic, we attempted to replicate the spatial-arithmetic association in addition and subtraction (Experiment 1), and at the same time investigated whether shift of spatial attention would also be induced by multiplication or division operations (Experiment 2). We found that solving addition problems facilitated the detection of right-side targets, whereas left-side targets were detected faster after solving subtraction problems. However, no interaction between space and arithmetic operation was observed in multiplication or division. The implication of these findings is discussed.

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Spatial–numerical associations (small numbers—left/lower space and large numbers—right/upper space) are regularly found in elementary number processing. Recently, the interest in this phenomenon has been extended from elementary number processing to mental arithmetic. Many studies have demonstrated horizontal spatial-arithmetic associations, i.e., solving addition or subtraction problems cause spatial shifts of attention rightward or leftward, respectively. However, the role of this effect in the vertical dimension has not been addressed. This is problematic because it leaves the analogy between elementary number processing and arithmetic incomplete. In order to make a strong case for a similarity between elementary number processing and mental arithmetic, a spatial-arithmetic association should be observed in the vertical dimension too. Here, we adopted the target detection paradigm from Liu et al. (2017) to replicate the horizontal spatial-arithmetic association, and meanwhile investigate whether this effect also exists in the vertical direction. Our results confirmed that addition could induce covert movement to right side and subtraction to left side. However, such a spatial-arithmetic association was not found in the vertical dimension. The implication of these findings is discussed.

The detachment of tumor cells from extracellular matrix and survival under anchorage-independence were recognized as the initial step of tumor metastasis. Previously we had demonstrated that anchorage-independence altered gene expressions and showed characteristics of cell invasiveness loss, enhanced chemosensitivity, and enhanced subcutaneous tumor formation. However, whether it affected histological phenotypes in tumor tissues remained unclear. Melanoma metastases were generated in nude mice using adherent or suspended melanoma cells. Examination of melanoma metastases revealed histological features of extensive vascular structures in adherent cell-derived tumors, while not seen in suspended cell-derived tumors. Quantitative proteomic analysis at adherent, suspended, and re-attached melanoma cells suggested that aminopeptidase N was potentially downregulated upon cell suspension or reattachment. Downregulation of aminopeptidase N by gene-specific shRNAs showed reduced cell invasiveness and enhanced subcutaneous tumor formation that was consistent with previous observations. Experiments by suppression or overexpression of aminopeptidase N expression demonstrated that aminopeptidase N regulated syndecan-1 and integrin β4 expression through PKCδ pathway. Histological analysis at melanoma metastases further suggested that CD31 + /aminopeptidase N + /syndecan-1 + /integrin β4 + phenotypes were associated with vascular structures. In summary, we suggested the expression axis of aminopeptidase N/syndecan-1/integrin β4 in melanoma cells was suppressed by detachment stress, which diminished vascular phenotypes of melanoma metastases.

As the most common pathogen of community and nosocomial infection, the resistance of Staphylococcus aureus (S. aureus) to traditional antibiotics is still increasing with years. Although the potent antibacterial activity of antimicrobial peptides (AMPs) has been widely confirmed, the unpredictable cytotoxicity remains the biggest obstacle to their clinical application. The development of a targeted drug delivery system for S. aureus is a practical strategy to ameliorate the inherent limitations of AMPs. In this work, we constructed an AMP release nanogel (cypate-GNPs@ Cy3-AMP, CGCA) of S. aureus infection microenvironment using gelatinase nanoparticles (GNPs) for toxicity control and bacterial clearance. Gelatinase present in the infected site degrades GNPs, thus releasing Cy3-AMP in situ to destroy bacterial cells. Cypate modified on the surface of GNPs supports CGCA to generate localized heat under near-infrared (NIR) laser irradiation, which together with AMPs could cause irreversible physical damage to bacteria. In addition, the encapsulation from GNPs not only effectively limited the toxicity of AMPs but also significantly promoted cell proliferation and migration in vitro. In the mouse infection model, CGCA also exhibited excellent effects of bacterial clearance and wound healing, providing a potential direction for the correct use of AMPs.