A detailed chronology has been obtained for a loess section at Yuanbao, situated at the northwestern edge of the Chinese Loess Plateau. The ages were obtained by the measurement of the optically ...stimulated luminescence (OSL) from coarse-silt-sized quartz grains. These ages showed that deposition at this site was continuous from 17 ka to the present, but that there was a decrease in the sedimentation rate from 0.60 to 0.10 m/ka at 13.489±1.15 ka, and this is proposed as the location of the Pleistocene/Holocene (P/H) boundary. A change in OSL sensitivity occurs at this depth. The depth and sharpness of this boundary is compared with the change obtained in low-field magnetic susceptibility (MS) measurements on 65 samples from the section. The MS changes gradually over 1.9 m and thus does not provide an easily discernible boundary. The new OSL-based sedimentation rates are used to calculate the mass accumulation rates for the Holocene and the end of the Pleistocene.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The effective estimation of the operational reliability of mechanism is a significant challenge in engineering practices, especially when the variance of uncertain factors becomes large. Addressing ...this challenge, a novel mechanism reliability method via a two-dimensional extreme distribution is investigated in the paper. The time-variant reliability problem for the mechanism is first transformed to the time-invariant system reliability problem by constructing the two-dimensional extreme distribution. The joint probability density functions (JPDFs), including random expansion points and extreme motion errors, are then obtained by combining the kernel density estimation (KDE) method and the copula function. Finally, a multidimensional integration is performed to calculate the system time-invariant reliability. Two cases are investigated to demonstrate the effectiveness of the presented method.
The aim of this study was to analyze myopericytoma in the oral and maxillofacial region in terms of clinical appearance, diagnosis, treatment, and outcomes.
Data on 5 new patients with myopericytoma ...in the oral and maxillofacial region treated at our department were collected and analyzed.
There were 2 males and 3 females (age range 10–62 years; mean age 43.8 years). All of the 5 patients presented with masses showing benign biologic behavior. Imaging examinations with use of computed tomography or magnetic resonance imaging showed heterogeneous regions with internal contrast-enhancement or cystic change in 3 cases. All of the patients underwent surgery. Histologic examination showed a broad morphologic spectrum characterized by concentric and perivascular growth of ovoid, plump spindled, and/or round myoid tumor cells. Immunohistochemical examination showed positive staining for vimentin and smooth muscle actin, and negative for CD34 and desmin. During the follow-up period (8–56 months), there was no tumor recurrence.
Myopericytoma in the oral and maxillofacial region always exhibits benign biologic behavior and a heterogeneous region with internal contrast-enhancement or cystic change on imaging examinations. Surgery is the first choice of treatment and results in good clinical outcomes.
•Our study is the first to explore and report the anti-tumor effect of carrimycin.•Carrimycin inhibits the proliferation, colony formation and migration ability of oral squamous cell carcinoma cells ...in vitro, as well as arrests cell cycle in G0/G1 and promotes cell apoptosis.•Carrimycin suppresses OSCC tumor growth in xenograft model.•Carrimycin regulates the PI3K/AKT and MAPK pathways.
: Carrimycin is a newly synthesized macrolide antibiotic with good antibacterial effect. Exploratory experiments found its function in regulating cell physiology, proliferation and immunity, suggesting its potential anti-tumor capacity. The aim of this study is to investigate the anti-tumor effect of carrimycin against human oral squamous cell carcinoma cells in vitro and in vivo.
: Human oral squamous cell carcinoma cells (HN30/HN6/Cal27/HB96 cell lines) were treated with gradient concentration of carrimycin. Cell proliferation, colony formation and migration ability were analyzed. Cell cycle and apoptosis were assessed by flow cytometry. The effect of carrimycin on OSCC in vivo was investigated in tumor xenograft models. Immunohistochemistry, western blot assay and TUNEL assays of tissue samples from xenografts were performed. The key proteins in PI3K/AKT/mTOR pathway and MAPK pathway were examined by western blot.
: As the concentration of carrimycin increased, the proliferation, colony formation and migration ability of OSCC cells were inhibited. After treating with carrimycin, cell cycle was arrested in G0/G1 phase and cell apoptosis was promoted. The tumor growth of xenografts was significantly suppressed. Furthermore, the expression of p-PI3K, p-AKT, p-mTOR, p-S6K, p-4EBP1, p-ERK and p-p38 were down-regulated in vitro and in vivo.
: Carrimycin can inhibit the biological activities of OSCC cells in vitro and in vivo, and regulate the PI3K/AKT/mTOR and MAPK pathways.
Previously, we conducted a randomized phase III trial of TPF (docetaxel, cisplatin, and 5-fluorouracil) induction chemotherapy in surgically managed locally advanced oral squamous cell carcinoma ...(OSCC) and found no improvement in overall survival. This study reports long-term follow-up results from our initial trial. All patients had clinical stage III or IVA locally advanced OSCC. In the experimental group, patients received two cycles of TPF induction chemotherapy (75mg/m2 docetaxel d1, 75mg/m2 cisplatin d1, and 750mg/m2/day 5-fluorouracil d1-5) followed by radical surgery and post-operative radiotherapy; in the control group, patients received upfront radical surgery and post-operative radiotherapy. The primary endpoint was overall survival. Among 256 enrolled patients with a median follow-up of 70 months, estimated 5-year overall survival, disease-free survival, locoregional recurrence-free survival, and distant metastasis-free survival rates were 61.1%, 52.7%, 55.2%, and 60.4%, respectively. There were no significant differences in survival rates between experimental and control groups. However, patients with favorable pathologic responses had improved outcomes compared to those with unfavorable pathologic responses and to those in the control group. Although TPF induction chemotherapy did not improve long-term survival compared to surgery upfront in patients with stage III and IVA OSCC, a favorable pathologic response after induction chemotherapy may be used as a major endpoint and prognosticator in future studies. Furthermore, the negative results observed in this trial may be represent type II error from an underpowered study. Future larger scale phase III trials are warranted to investigate whether a significant benefit exists for TPF induction chemotherapy in surgically managed OSCC.
Abstract
In this paper, the electronic structure and stability of the intrinsic, B-, N-, Si-, S-doped graphene are studied based on first-principles calculations of density functional theory. ...Firstly, the intrinsic, B-, N-, Si-, S-doped graphene structures are optimized, and then the forming energy, band structure, density of states, differential charge density are analyzed and calculated. The results show that B- and Si-doped systems are p-type doping, while N is n-type doping. By comparing the forming energy, it is found that N atoms are more easily doped in graphene. In addition, for B-, N-, Si-doped systems, it is found that the doping atoms will open the band gap, leading to a great change in the band structure of the doping system. Finally, we systematically study the optical properties of the different configurations. By comparison, it is found that the order of light sensitivity in the visible region is as follows: S-doped> Si-doped> pure > B-doped > N-doped. Our results will provide theoretical guidance for the stability and electronic structure of non-metallic doped graphene.
Due to the limited sample size of the clinical N2 group, our retrospective subgroup analyses were not sufficient to guide further treatment plan until further demonstrated by convincing studies. ...Besides clinical indicators, we also focused on the predictive effect of pathological response after induction chemotherapy. The pCR rate was consistent with another trial investigating split TPF induction chemotherapy regimen in oral and oropharyngeal squamous cell cancer, in which pCR rate was 31.5% (17/54) 6. Since the pCR rate of induction chemotherapy was relatively low, major pathological response (MPR) or FPR, which were both defined as ≤10% of residual viable tumor after induction chemotherapy, were used as surrogate criteria of pathological response evaluation and endpoints for survival 3. No significant difference in baseline characteristics, including the T stage or TNM stage, was observed between patients with and without FPR, suggesting that FPR could be considered as a prognostic predictor for induction chemotherapy in OSCC. ...increasing the FPR rate of OSCC patients receiving induction treatment is crucial. Attempts to intensify TPF with cetuximab to increase efficacy on HNSCC demonstrated no significant effectiveness but was rather toxic 7. Since immunotherapy demonstrated efficacy in HNSCC and some other cancers, such as esophageal squamous cell carcinoma and triple-negative breast cancer, with excellent tolerability, it has been currently tested in combination with chemotherapy 8, 9.
The aim of this study was to investigate the oncogenic function and regulatory mechanism of stathmin in oral squamous cell carcinoma (OSCC).
Two-dimensional electrophoresis and liquid ...chromatography-tandem mass chromatography were applied to screen differentiated proteins during carcinogenesis in OSCC. Cell Counting Kit-8 (CCK-8) assays, colony formation, migration, flow cytometry, immunofluorescence and a xenograft model were used to detect the function of stathmin. The correlation between stathmin and p53 expression was analyzed using immunohistochemistry. Mutant/wild type p53 plasmids and small interfering RNA were used to examine the regulation of stathmin. Chromatin immunoprecipitation assays and luciferase assays were performed to detect the transcriptional activation of stathmin by p53.
Overexpression of stathmin was screened and confirmed in OSCC patients and cell lines. Silencing expression of stathmin inhibited proliferation, colony formation and migration and promoted apoptosis. Poly ADP ribose polymerase (PARP) and cyclin-dependent kinase 1 (cdc2) were activated after silencing the expression of stathmin. Suppression of tumorigenicity was also confirmed in vivo. Mutant p53 transcriptionally activated the expression of stathmin in HN6 and HN13 cancer cells, but not in HN30 cells harboring wild type p53.
These results suggest that stathmin acts as an oncogene and is transcriptionally regulated by mutant p53, but not by wild-type p53. Stathmin could be a potential anti-tumor therapeutic target in OSCC.
The aim of this study was to retrospectively analyze the clinical characteristics, surgical treatment, and prognosis of patients with diffuse-type tenosynovial giant cell tumor (D-TGCT) involving the ...temporomandibular joint (TMJ) and the skull base.
A retrospective study was performed in patients with D-TGCT involving the TMJ and the skull base at our institute from April 2009 to August 2018. Data on clinical characteristics, surgical treatment, and prognosis were collected and analyzed. A literature search on D-TGCT involving the TMJ was conducted and the data analyzed.
The study included 22 patients (14 males and 8 females), with an average age of 44 years. The main symptoms were headache and hearing limitation, accompanied by a swelling in the TMJ area. Magnetic resonance imaging (MRI) showed low signals on T1- and T2-weighted images. All lesions were completely removed. Temporal bone flap, titanium mesh, and temporal muscle flap were used for reconstruction. The recurrence rate was 4.5%. In the literature, 115 cases were reported. Surgery alone was performed in 88 cases; postoperative radiotherapy was performed in 19 cases; the tumor recurrence rates were 9.1% and 15.8% for the 2 procedures, respectively. All patients were alive at the end of the follow-up period.
D-TGCT involving the TMJ and the skull base is a locally aggressive but benign lesion necessitating complete resection and has a good prognosis.
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