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The phytochemical investigation on the rhizomes of Dryopteris crassirhizoma (Dryopteridaceae) resulted in the discovery of one novel compound, drycrassirhizomamide A (1), and one new natural product, drycrassirhizomamide B (2), as well as four known isolates, (S)-(-)-N-benzoylphenylalaninol (3), blumenol A (4), 8-C-glucosylnoreugenin (5), and dryopteroside (6). Their chemical structures were identified by NMR and mass spectroscopy. Compounds 1-2 were determined to be 1,19-diethyl 10-oxo-2,9,11,18-tetraazanonadecanedioate and C,C′-diethyl N,N′-1,6-hexanediylbis[carbamate]. The anti-inflammatory activities of these compounds were evaluated with LPS-stimulated RAW264.7 macrophage and BV2 microglia. The results showed that compounds 1-3 and 6 have inhibitory effects of NO production with IC50 values of 13.41, 30.36, 25.51, and 11.35 μM in LPS-stimulated RAW264.7 cells. Also, compounds 1 and 4-6 have abilities to inhibit NO production with the IC50 values of 40.11, 30.94, 15.76, and 16.79 μM in BV2 cells, which demonstrated that they may possess the potential anti-inflammatory activity. [ABSTRACT FROM AUTHOR]

BACKGROUND: Oral squamous cell carcinoma (OSCC) is an infiltrative malignancy characterized by a significantly elevated recurrence rate. Dickkopf-related protein 1 (DKK1), which plays an oncogene role in many cancers, acts as an inhibitor of the Wingless protein (Wnt) signaling pathway. Currently, there is a lack of consensus regarding the role of DKK1 in OSCC or its clinical significance. OBJECTIVE: To examine the role and effect of DKK1 in OSCC. METHODS: The identification of differentially expressed genes (DEGs) in OSCC was conducted by utilizing databases such as The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). A comprehensive analysis of gene expression profile interactions (GEPIA) and Kaplan-Meier curve were conducted to investigate the associations among DEGs, patient survival and prognosis in individuals with OSCC. The biological function of DKK1 in OSCC was investigated by using molecular biology approaches. RESULTS: The expression of DKK1 was found to be upregulated in OSCC tissues at various stages. High levels of DKK1 expression exhibited a positive correlation with the overall survival (OS) and progression-free survival (PFS) rates among OSCC patients. DKK1 knockdown suppressed the proliferation and induced apoptotic response in OSCC cells. Moreover, DKK1 exerted a positive regulatory effect on HMGA2 expression, thereby modulating cell growth and apoptosis in OSCC. The expression of DKK1 was found to be positively correlated with the infiltration of immune cells in patients with OSCC. Additionally, higher levels of CD4 + T cells were associated with improved 5-year survival rates. CONCLUSION: DKK1 is a prognostic biomarker for patients with OSCC. [ABSTRACT FROM AUTHOR]

Based on the safety assessment framework and site-specific characteristic investigations in northwest China, an approach to deriving the specific activity limit of 239Pu is applied to establish a proposed value. Our analyses, in conjunction with the results of other previous studies, allow for the following conclusions: (1) As an intrusion scenario with a feature of minimal site-dependence and pervasive applicability, the drilling scenario can be used as the limiting scenario for the post-closure period; (2) Given a dose limit of 5 mSv per year, a derived specific activity of 287 Bqg-1 (at a disposal depth shallower than 5 m) for 239Pu is obtained through the formulation of models and subsequent calculations. It is suggested that both our approaches to deriving the limit and the results can be effectively applied to establish acceptance criteria of long-lived transuranic nuclides, for the particular disposal facility; and (3) From the standpoint of exploring the approach for limit derivation, the intrusion scenario and the corresponding exposure evaluation can be the focus of concern in the study area. It is implied that, in arid regions, a leaching scenario may lead to a more complex evaluation, with unnecessary effort, and can be virtually excluded.

Objective To simulate the hypoxic environment of cells in vivo more approximately, a hypoxia control device which can control oxygen concentration automatically for cell culture in vitro was developed. Methods In vitro cell culture hypoxia control device consisted of hardware and software which were controlled by computer. The hardware was composed of oxygen detection and control system, nitrogen gas pipeline, cell culture and anti⁃jamming device, and the software was based on Clanguage. When oxygen controlle rreads the oxygen concent ration more than the set value, the nitrogen gas pipeline opens and nitrogen enter into the incubator; when reaching the set value, the nitrogen gas pipe⁃ line closes and nitrogen is not allowed to pass through. Circularly, a constant oxygen concentration was reached and maintained. This device was further verified by comparing the set value of the equipment with figures of the oxygen me⁃ ter and by monitoring fluctuation condition after the oxygen concentration reaching the set value. Results There was no significant difference between the oxygen concentration set in the in vitro cell culture hypoxia control device and the actual oxygen concentration in the measured box (P > 0.05), and the accuracy of the device to set the value of the simu⁃ lation up to ± 0.5% of the requirements to meet the system accuracy requirements, and can remain stable for a long time. Conclusion The device can effectively control the oxygen concentration to the required requirements, to meet the conditions in the hypoxic conditions for in vitro cell culture.

In order to improve the efficiency of Z/Q-Z source inverter and output current quality，reduce the harmonic distortion rate of grid-connected current，the control strategy of grid-connected current is applied to the Z/Q-Z source inverter. The deadbeat control is used to realize grid-connection control，The current can track the reference current quickly，realize the single power factor operation，and the digital control of the inverter. Z/Q-Z source grid-connected inverter simulation model is established，and the grid-connected system of Z/Q-Z source in- verter is simulated and analyzed to prove the validity and feasibility of the grid-connected control strategy. The sim- ulation results show that the total harmonic distortion rate of the grid-connected current is less than 1%，the quality of grid-connected current is improved，and the capacitor voltage value of Q-Z source inverter is about half order of magnitude smaller than the Z inverter network. Moreover soft start control of the Z/Q-Z source inverter is analyzed， soft start can effectively solve the start impact of the Z source capacitor voltage and inverter bridge voltage.

Objective To establish the three-dimensional finite element simulation model of periodontal membrane by micro-CT scanning data. Methods A human maxillary jaw segment containing central incisor was scanned with micro-CT for section images, which were managed with Mimics software to form a geometric model. The model was imported to remesh module for optimization and then the three-dimentional finite element model was constructed by Ansys. Results The three-dimensional finite element models encompassing 12 936 nodes and 6 400 tetrahedral element, which highly resemble the structure of periodontal ligament. Tooth (60 872 nodes and 42 144 tetrahedral element) and alveolar bone models (41 472 nodes and 32 339 tetrahedral element) were constructed successfully. Conclusion The three-dimen- sional finite element simulation model of periodontal membrane can be established by micro-CT combined with Mimics and Ansys software. After adding the corresponding tooth alveolar bone, it can be further used in orthodontic biomechanicsanalysis.