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Simple Summary: Gastric cancer (GC) is one of the most common malignancies with limited therapeutic targets available. CDR1as, an endogenous circular RNA with a closed loop structure, has been reported to be a crucial regulator and promising biomarker in various tumors. However, whether and how CDR1as participates in GC progression remains not well characterized. In this study, we explored the biological roles, the downstream molecular mechanism and the upstream regulator of CDR1as in GC. We found that CDR1as mediated by human antigen R (HuR) promotes GC growth through the miR-299-3p/TGIF1 axis, which provides new insights into GC pathogenesis and brings a new potential target for clinical GC therapy. Background: Gastric cancer (GC) remains a common malignancy worldwide with a limited understanding of the disease mechanisms. A novel circular RNA CDR1as has been recently reported to be a crucial regulator of human cancer. However, its biological role and mechanism in the GC growth are still far from clear. Methods: Small interfering RNAs (siRNAs), lentivirus or plasmid vectors were applied for gene manipulation. The CDR1as effects on the GC growth were evaluated in CCK8 and colony formation assays, a flow cytometry analysis and mouse xenograft tumor models. A bioinformatics analysis combined with RNA immunoprecipitation (RIP), RNA pull-down assays, dual-luciferase reporter gene assays, Western blot, reverse transcription–quantitative polymerase chain reaction (RT-qPCR) and functional rescue experiments were used to identify the CDR1as target miRNA, the downstream target gene and its interaction with human antigen R (HuR). Results: The CDR1as overexpression promoted the GC growth in vitro and in vivo and reduced the apoptotic rate of GC cells. Its knockdown inhibited the GC cell proliferation and viability and increased the cell apoptotic rate. Proliferation-related proteins PCNA and Cyclin D1 and apoptosis-related proteins Bax, Bcl-2, Caspase-3 and Caspase-9 were regulated. Mechanically, the cytoplasmic CDR1as acted as a miR-299-3p sponge to relieve its suppressive effects on the GC cell growth. Oncogenic TGIF1 was a miR-299-3p downstream target gene that mediated the promotive effects of CDR1as and regulated the PCNA and Bax levels. HuR interacted with CDR1as via the RRM2 domain and positively regulated the CDR1as level and its oncogenic role as well as downstream target TGIF1. Conclusions: CDR1as promotes the GC growth through the HuR/CDR1as/miR-299-3p/TGIF1 axis and could be used as a new therapeutic target for GC. [ABSTRACT FROM AUTHOR]

Objective To investigate the characteristics of 18F-S16 PET imaging in brain tissue of patients with behavioral variant frontotemporal dementia (bvFTD) and the correlation between tau protein deposition and glucose metabolism pattern. Methods A total of 12 bvFTD patients and 10 controls with normal cognitive function treated in Tianjin Medical University General Hospital from January 2020 to October 2021 were included, and all of them underwent 18F-S16 PET and 18F-FDG PET. The difference of 18F-S16 and 18F-FDG uptake between bvFTD group and control group was compared by voxel-based analysis (VBA). The 18F-S16 and 18F-FDG standard uptake value rate (SUVR) of 2 groups were compared by semi- quantitative analysis. The 18F - S16 uptake rate of 2 groups was observed by visual analysis. Pearson correlation analysis was used to explore the whole-brain spatial correlation of 18F-S16 and 18F-FDG tracers and the correlation of uptake levels in each region of interest (ROI). Results VBA method showed the uptake of 18F-S16 increased in the right superior frontal gyrus, bilateral middle frontal gyrus and inferior frontal gyrus, bilateral anterior central gyrus, bilateral middle temporal gyrus, right inferior temporal gyrus, right posterior central gyrus and left inferior parietal lobule in bvFTD patients (P < 0.01, for all, FWE correction, pixel threshold = 50). The uptake of 18F-FDG in bilateral superior frontal gyrus, bilateral middle frontal gyrus, right inferior frontal gyrus, bilateral anterior cingulate gyrus and right insula decreased in bvFTD patients (P = 0.000, for all, FWE correction, pixel threshold = 50). The overlaps were mainly located in the right superior frontal gyrus, bilateral middle frontal gyrus and right inferior frontal gyrus. Semi - quantitative analysis showed the SUVR value of tau protein in bilateral frontal lobe (P = 0.000), parietal lobe (P = 0.015) and precuneus (P = 0.000) in bvFTD group was higher than that in control group, and the SUVR value of glucose in bilateral frontal lobe was lower than that in control group (P = 0.002). Pearson correlation analysis showed the whole-brain spatial correlation between 18F-S16 and 18F-FDG was weak in bvFTD patients (r = 0.050, P = 0.000). In bvFTD patients, only bilateral frontal tau SUVR was negatively correlated with glucose SUVR (r = - 0.702, P = 0.011). Visual analysis of 18F-S16 PET showed increased uptake in bilateral frontal, parietal, precuneus, and hippocampus in bvFTD patients. Conclusions 18F-S16 PET can reflect the characteristic of tau protein deposition and its correlation with glucose metabolic pattern in bvFTD patients. [ABSTRACT FROM AUTHOR]

Purpose: The removal of three inverted triangular parallel cannulated screws after the femoral neck fracture healing is sometimes accompanied by osteonecrosis of the femoral head (ONFH) or its refracture. The purpose of this study was to determine the biomechanical changes of the femur before and after the screw removal using a finite element analysis.Methods: The CT data of the femurs were obtained from a 69-year-old healthy female to establish the femur models. The established finite element models consisted of N, C, and R groups: N group, the normal femur; C group (to simulate the femoral neck fracture healing after the internal fixation), the normal femur with three inverted triangular parallel cannulated screws (C1) or with two upper parallel screws (C2). For the R1 or R2 groups, the screws in the model of the C1 or C2 individuals were gradually removed in seven or three types of different screw combinations, respectively. The stresses and displacements of the femur were determined.Results: (1) Compared with the N group, a uniform stress distribution was stopped by the addition of three screws in the C1 group; in contrast, all screw removals resulted in the stress concentration on the screw holes and the disappearance of stress shielding. Moreover, the average stress of the femoral head in C1 group increased by 37.85%, while that of the femoral neck decreased by 23.03%. (2) Compared with the C1 group, while only the lowest femoral calcar screw was removed, there was a similar stress distribution in the proximal femur, and the average stress of the femoral head increased only by 0.35% although that of the femoral neck increased by 63.62%; however, removal by any other means resulted in a significant stress concentration in the proximal femur and a significant increase in the average stresses of the femoral head and neck (5.96-40.95% and 12.82-75.46%, respectively). (3) Compared with the N or C1 group, there was a significant stress concentration on the screws and its surrounding proximal femur in the C2 group. (4) Compared with the C2 group, the simultaneous removal of two upper screws not only did not cause a significant stress concentration on the proximal femur but also significantly reduced the average stresses of the femoral head and neck by 87.49% and 65.51% respectively. On the contrary, the gradual removal of two screws caused a significant stress concentration on the screw and its surrounding proximal femur although the average stresses of the femoral head and neck decreased by 88.79-89.06% and 67.00-67.22%, respectively. (5) Compared with the N group, the average displacements of the femoral head and neck in the C1 group increased only by 3.12% and 3.37%, respectively. Additionally, compared with the C1 group, while three, two, or one screw was simultaneously removed, the average displacements of the femoral head and neck only fluctuated - 5.51-1.65% and 1.78-9.03%, respectively.Conclusions: Residual internal fixation after femoral neck fracture healing may lead to stress concentration on screws and stress shielding around screws. The first removal of the lowest femoral calcar screw and then the second removal of two upper residual screws have a minimum effect on the stress concentration on the proximal femur and the average stress on the femoral head. The incorrect screw removal and resulting femoral load may well be closely related to occurrence in ONFH or its refracture. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) and frontotemporal dementia (FTD) are two common forms of primary neurodegenerative dementia. Mutations in 3 genes (PSEN1, PSEN2, and APP) have been identified in patients with early-onset AD. Methods: We performed gene sequencing in PSEN1, PSEN2, and APP in 61 AD and 35 FTD Chinese patients. Amyloid load using 11C-labeled Pittsburgh compound B (11C-PIB) positron emission tomography (PET) and cerebral glucose metabolism using 18F-fludeoxyglucose PET were evaluated in patients carrying mutations. Results: We identified 1 known pathogenic PSEN1 (p.His163Arg, c.488A>G) mutation and 3 novel PSEN2 mutations in 6 patients. The novel mutation PSEN2 (p.His169Asn, c.505C>A) was identified in 1 patient with familial late-onset AD and in 1 sporadic FTD patient. The PSEN2 (p.Val214Leu, c.640G>T; p.Lys82Arg, c.245A>G) mutations were identified in 2 early-onset AD patients and 1 early-onset AD patient, respectively. Three patients with PSEN2 mutations were observed to have PIB retention on the cortex and striatum. One patient with the FTD phenotype was not observed to have PIB retention. Conclusion: PSEN2 mutations are common in the Chinese Han population with a history of AD and FTD. Pathogenic mutations or risk variants in the PSEN2 gene can influence both FTD and AD phenotypic traits and show variations in neuroimaging characterization. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Nuclear factor I-C (NFIC) has an important role in the development of murine dental roots, but its role in human root formation is unreported. We thus elucidated the regulatory role of NFIC in the differentiation of human stem cells from the apical papilla (hSCAPs). The first step for this was to determine the expression of NFIC in human teeth, and it was found that NFIC expression was restricted to the odonto-blasts and preodontoblasts of the developing molars of humans and mice. NFIC was found to be expressed in odontoblast-like cells after the subcutaneous transplantation of hSCAPs. NFIC expression was concomitant with dentin sialophosphoprotein (DSPP) in the mineralization of hSCAPs. NFIC knockdown in hSCAPs significantly inhibited expression of DSPP and promoted that of dentin matrix protein 1 (DMP1), meanwhile upregulated the expression of TGF-β1 and downregulated SMAD3 and SMAD4. NFIC expression was significantly upregulated after TGF-β1 treatment in hSCAPs. NFIC knockdown prolonged G1 phase of the cell cycle, but had no effect on cell proliferation and migration. These results suggest that NFIC is involved in the development of human root dentin and the regulation of odontoblastic differentiation of hSCAPs. NFIC may participate in the DMP1-DSPP signaling pathway and comprises a complex signaling cycle with TGF-β1. [ABSTRACT FROM AUTHOR]

Background: Vancomycin-resistant Enterococcus spp. (VRE) have spread all over the world. The present study aims to investigate the species distribution, specimen type and susceptibilities of Enterococcal species collected from Nanjing Drum Tower Hospital from 2013 to 2018. Additionally, distribution of VRE and prevalence of van gene among VRE isolates were also analyzed.Methods: The susceptibilities of 3913 Enterococcus isolates were retrospectively investigated. Among these strains, 60 VRE strains were further anazlyed in this study. The minimum inhibitory concentrations (MICs) of the VRE strains towards vancomycin, teicoplanin and linezolid were determined by E-test. Polymerase chain reaction (PCR) and DNA sequencing were used to investigate the prevalence of van genes among VRE. Furthermore, the sequence types (STs) of VRE strains were explored by multi-locus sequence typing (MLST).Results: Among the 3913 enterococci isolates, Enterococcus faecalis (n = 1870, 47.8%) and Enterococcus faecium (1738, 44.4%) were the main isolates. These Enterococcus strains were mainly isolated from urine (n = 1673, 42.8%), followed by secretions (n = 583, 14.9%) and ascites (n = 554, 14.2%). VRE displayed a decreasing trend year by year. Molecular analysis revealed that 49 out of 60 VRE isolates carried vanA gene, 10 carried vanM, and 1 carried both vanA and vanM genes. Sixteen distinct STs were identified among the 58 VREM, with ST78 (n = 16), ST192 (n = 8) and ST570 (n = 7) being the most dominant ones.Conclusions: E. faecalis and E. faecium were the major enterococci strains which are the main pathogens of urinary traction infections; vanA and vanM were the main determinants conferring resistance to vancomycin; ST78, ST192 and ST570 were the leading STs of VREM which displayed a decreasing trend of prevalence year by year. [ABSTRACT FROM AUTHOR]

Two new compounds, triacremoniate (1) and dietziamide C (2) along with known compounds β-Adenosine (3) and acrepyrone A (4) were obtained from the mangrove-derived fungus Acremonium citrinum. MMF4. Their structures were unambiguously determined by extensive spectroscopic methods, including UV, IR, HRESIMS and NMR. Triacremoniate (1) can promote apoptosis of HeLa cells by increasing the PARP cleavage and the phosphorylation of JNK and p38. Unlabelled Image • Two new compounds were obtained from the mangrove-derived fungus Acremonium citrinum. • Compound 1 showed obvious cytotoxicity against Hela cell line. • Compound 1 distinctly induced the apoptosis of Hela cell line. • Compound 1 significantly increased the expression of p-JNK and p-p38 in MAPK signaling pathway. [ABSTRACT FROM AUTHOR]