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The pathogenesis of oral squamous cell carcinoma (OSCC) remains unclear. Therefore, clarifying its pathogenesis and molecular-level development mechanism has become the focus of OSCC research. N-acetyltransferase 10 (NAT10) is a crucial enzyme involved in mRNA acetylation, regulating target gene expression and biological functions of various diseases through mediating N4-acetylcytidine (ac4C) acetylation. However, its role in OSCC progression is not well understood. In this study, we showed that NAT10 was significantly upregulated in OSCC tissues compared to normal oral tissues. Moreover, lentivirus-mediated NAT10 knockdown markedly suppressed cell proliferation, migration, and invasion in two OSCC cell lines (SCC-9 and SCC-15). Interestingly, MMP1 was found to be significantly upregulated in OSCC tissues and was a potential target of NAT10. N-acetyltransferase 10 knockdown significantly reduced both the total and ac4C acetylated levels of MMP1 mRNA and decreased its mRNA stability. Xenograft experiments further confirmed the inhibitory effect of NAT10 knockdown on the tumorigenesis and metastasis ability of OSCC cells and decreased MMP1 expression in vivo. Additionally, NAT10 knockdown impaired the proliferation, migration, and invasion abilities in OSCC cell lines in an MMP1-dependent manner. Our results suggest that NAT10 acts as an oncogene in OSCC, and targeting ac4C acetylation could be a promising therapeutic strategy for OSCC treatment.

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This study aims to investigate pedestrian crossing behavior and safety at uncontrolled mid-block crosswalks with different numbers of vehicle lanes. For this purpose, twelve uncontrolled mid-block crosswalks in Wuhan, China were selected to collect data via field investigation. Descriptive statistics were used to analyze pedestrian crossing behavior, and the distribution of pedestrian-vehicle conflicts on different vehicle lanes was given. Three ordered probit (OP) models for pedestrian-vehicle conflicts analysis (PVCA) were established to measure the effects of various factors on pedestrian safety. Descriptive statistical results showed that crosswalks with different numbers of lanes have diverse impacts on pedestrian crossing behavior and safety. As the number of vehicle lanes increases, the proportion of pedestrians adopting the rolling gap crossing mode, crossing the street with others, and changing the speed or path increase accordingly. Moreover, the number of pedestrian-vehicle conflicts at two-way six-lane crosswalks is 5.96 times higher than that of two-lane crosswalks, and 2.04 times higher than that of four-lane crosswalks. From the results of OP models, it was found that pedestrian behavioral characteristics such as rolling gap crossing mode, crossing with others significantly increased the possibility of pedestrian-vehicle conflicts.

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INTRODUCTION: The gap acceptance theory was primarily used to study pedestrian crossing behaviors, in accordance to static gaps that are calculated in the light of the cross section of crosswalk. However, pedestrians will face a series of dynamic gaps (especially at any uncontrolled multi-lane crosswalk) when they decide to cross the street, thus, pedestrians' decisions are made based on the dynamic gaps of each lane. METHOD: Pedestrians' crossing behaviors at uncontrolled multi-lane mid-block crosswalk were investigated in this study. The lane-based gap (LGAP) was defined and five mid-block crosswalks were selected for observation in Wuhan, China. Pedestrians' behaviors and the corresponding traffic statuses were videoed as collected data, whose statistical analysis indicates that most pedestrians choose the rolling gap crossing strategy, which is different from existing research. Moreover, a logistic regression model was established to evaluate various influencing parameters (such as gender, age, waiting time and traffic volume) on the pedestrians' crossing strategy, whose accuracy is not satisfying. Therefore, the pedestrian dynamic gap acceptance (PDGA) model was put forward to describe pedestrians' crossing behaviors at any multi-lane crosswalk based on detailed analysis of the pedestrians' decision procedure. RESULTS: The corresponding results show that its accuracy may be up to 88.6% to well describe pedestrians' crossing behaviors. CONCLUSIONS: The PDGA model is appropriate to analyze pedestrians' dynamic decision procedures at multi-lane mid-block crosswalks. PRACTICAL APPLICATION: The findings of this study can be used for safety and performance evaluation of crosswalks at mid-block locations in developing countries like China and India.

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A lot of pedestrian-vehicle crashes at mid-block crosswalks severely threaten pedestrian's safety around the world. The situations are even worse in China due to low yielding rate of vehicles at crosswalks. In order to quantitatively analyze pedestrian's safety at multi-lane mid-block crosswalks, the number of pedestrian-vehicle conflicts was utilized to evaluate pedestrian's accident risk. Five mid-block crosswalks (Wuhan, China) were videoed to collect data of traffic situation and pedestrian-vehicle conflicts, and the quantity and spatial distribution of pedestrian-vehicle conflicts at multi-lane mid-block crosswalk were analyzed according to lane-based post-encroachment time(LPET). Statistical results indicate that conflicts are mainly concentrated in lane3 and lane6. Percentage of conflict of each lane numbered from 1 to 6 respectively are 4.1%, 13.1%, 19.8%, 8.4%, 19.0%, 28.1%. Conflict rate under different crossing strategies are also counted. Moreover, an order probit (OP) model of pedestrian-vehicle conflict analysis (PVCA) was built to find out the contributions corresponding to those factors (such as traffic volume, vehicle speed, pedestrian crossing behavior, pedestrian refuge, etc.) to pedestrian-vehicle conflicts. The results show that: pedestrian refuge have positive effects on pedestrian safety; on the other hand, high vehicle speed, high traffic volume, rolling gap crossing pattern, and larger pedestrian platoon have negative effects on pedestrian safety. Based on our field observation and PVCA model, the number of conflicts will rise by 2% while the traffic volume increases 200 pcu/h; similarly, if the vehicle speed increases 5km/h, the number of conflicts will rise by 12% accordingly. The research results could be used to evaluate pedestrian safety at multi-lane mid-block crosswalks, and useful to improve pedestrian safety by means of pedestrian safety education, pedestrian refuge setting, vehicle speed limiting, and so on.

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Manganese oxides are promising high-capacity anode materials for lithium-ion batteries (LIBs) yet suffer from short cycle life and poor rate capability. Herein, we demonstrate a facile in situ interfacial synthesis of core-shell heterostructures comprising nitrogen-enriched porous carbon (pN-C) nanocoating and manganese oxide (MnOx) nanotubes. When MnOx/pN-C serves as an anode material for LIBs, the pN-C coating plays multiple roles in substantially improving the lithium storage performance. In combination with the nanosized structure and nanotubular architecture, the MnOx/pN-C nanocomposites exhibit an impressive reversible capacity of 1068 mAh g(-1) at 100 mA g(-1), a high-rate delivery of 361 mAh g(-1) at 8 A g(-1), and a stable cycling retention up to 300 cycles. The surface pN-C coating strategy can be extended to design and fabricate various metal oxide nanostructures for high-performance LIBs.

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OBJECTIVE: To examine the cytokeratin expression in cervical lymph nodes of patients with mandibular gingival squamous cell carcinoma and its clinical significance. METHODS: The data of 42 cases with mandibular gingival squamous cell carcinoma after operation from July 2009 to December 2012 were included. Forty-two patients (male = 27, formale = 15) were included, with a mean age of 54.1 years (range 27-77). The lesions were staged (stage I:9, stage II:16, stage III:6, stage IV:11). The cervical lymph nodes were examined by immunohistochemistry and HE. The cytokeratin expression in the lymph nodes was analyzed. RESULTS: The rates of lymph nodes metastasis detected by routine HE staining, serial sections HE staining and IHC were 8.0% (47/585), 9.6% (56/585) and 12.8% (75/585), respectively. There was significant difference (χ(2) = 7.17, P < 0.01) in the diagnosis of lymph nodes metastasis between IHC and routine HE staining, There was no significant difference between IHC and serial HE staining (χ(2) = 3.10, P > 0.05). Metastasis occurred mainly in the Level I, II and III. Nineteen lymph nodes in 12 patients were found micrometastasis with IHC. Serial sections and routine HE staining did not find micrometastasis. CONCLUSIONS: CK markers is sensitive in detecting lymph node metastasis of mandibular gingival squamous cell carcinoma.

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