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Although there have been recent advances in the molecular pathology of ependymomas, little is known about the underlying molecular evolution during its development. Here, we assessed the clinical, pathological and molecular evolutionary process of ependymoma recurrence in a 9-year-old patient who had seven recurrences of supratentorial ependymoma and died from intracranial multiregional recurrences at the age of 19 years old. Whole-genome sequencing (WGS) of 7 tumor samples (1 primary and 6 subsequent recurrent tumors) was performed to elucidate the mutation landscape and identify potential driver mutations for tumor evolution. The genetic profiles of the seven tumor specimens showed significant heterogeneity and suggested a highly branched evolutionary pattern. The mutational signatures and chromothripsis changed with treatments. Strikingly, adhesion G protein-coupled receptor L3 (ADGRL3, also known as Latrophilins 3, LPNH3) was found to be consistently mutated during the entire disease process. However, Sanger sequencing of other 78 ependymoma patients who underwent surgery at our institution showed no genetic alteration of ADGRL3, as found in the present case. The mRNA levels of ADGRL3 were significantly lower in ependymomas (n = 36), as compared with normal brain tissue (n = 3). Grade III ependymomas had the lowest ADGRL3 expression. Moreover, ependymomas with lower mRNA level of ADGRL3 had shorter overall survival. Our findings, therefore, demonstrate a rare evolutionary process of ependymoma involving ADGRL3.

Introduction Surgical resection of medulloblastoma (MB) remains a challenge. At present, a variety of tracers have been used for intraoperative tumor visualization. However, there are few reports on the intraoperative visualization of MB. Hence, we reported our experience of applying fluorescein sodium (FS) in MB surgery. Methods We retrospectively analyzed the clinical information of patients with MB confirmed by surgery and pathology from January 2016 to December 2020 from Sun Yat-sen University Cancer Center. A total of 62 patients were enrolled, of which 27 received intraoperative FS and 35 did not. The intraoperative dose of FS was 3 mg/kg. Results Among the 62 patients, 42 were males, and twenty were females. The age of onset in the FS group was 9.588 ± 7.322, which in the non-fluorescein sodium group was 13.469 ± 10.968, p = 0.198. We did not find significant differences in tumor location, tumor size, tumor resection, tumor histology, and preoperative symptoms (hydrocephalus, headache, vomit, balance disorder) between the groups. There was no significant difference in the postoperative symptoms (hydrocephalus, headache, vomiting, balance disorder, and cerebellar mutism). However, patients in the FS group had a relatively low incidence of balance disorder and cerebellar mutism. There was definite fluorescence of tumor in all cases of the FS group, and even the tiny metastatic lesion was visible. No case had side effects related to the use of FS. Conclusions FS is safe and effective in MB surgery. Whether the application of FS for surgery can reduce complications remains to be studied in the future.

Lin-lin Pei,1,* Wen-zhu Yang,1,* Jing-yuan Fu,1,* Meng-xi Liu,1 Ting-ting Zhang,1 Dong-bo Li,1 Ruo-yue Huang,1 Li Zhang,1 Guang-neng Peng,1 Gang Shu,1 Zhi-xiang Yuan,2 Ju-chun Lin,1 Wei Zhang,1 Zhi-jun Zhong,1 Ling Zhao,1 Hua-lin Fu1 1Department of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, People’s Republic of China; 2College of Pharmacy, Southwest Minzu University, Chengdu, Sichuan, People’s Republic of China*These authors contributed equally to this workCorrespondence: Hua-lin FuDepartment of Pharmacy, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, People’s Republic of ChinaTel +86 028-86291162Email fuhl2005@sohu.comIntroduction: Enrofloxacin is used in the treatment of a wide variety of bacterial infections in mammals. However, its poor solubility limits the clinical use.Methods: In order to improve the solubility of enrofloxacin, the enrofloxacin mesylate (EM) were obtained by a chemical synthesis method. The characterization of EM was carried out using ultraviolet scan (UV), synchronous thermal analysis (SDT), fourier transform infrared spectrometer (FTIR) and mass spectrometry (MS), nuclear magnetic resonance (NMR) and X-ray powder diffraction analysis (XRPD). Acute toxicity of EM in Kunming mice was studied. Besides, pharmacokinetic studies were performed in New Zealand rabbits at a single oral dose of 10 mg/kg, and the antibacterial activity of EM was also evaluated.Results: EM was successfully synthesized and purified. The stoichiometric ratio of mesylate to enrofloxacin was 1:1 and the aqueous solubility of EM was 483.01± 4.06 mg/mL, the solubility of EM was about 2000 times higher than enrofloxacin. The oral lethal dose (LD50) of EM was 1168.364 mg/kg, and the pharmacokinetics indicated that the oral relative bioavailability of EM was about 1.79 times and 1.48 times higher than that of enrofloxacin and enrofloxacin hydrochloride, respectively. In addition, the in vitro antibacterial activity of EM was not significantly changed compared with enrofloxacin and enrofloxacin hydrochloride.Conclusion: EM has higher solubility, low toxicity for oral use, and increases the oral bioavailability in rabbit. This study may be of benefit for the development of new enrofloxacin drugs.Keywords: enrofloxacin mesylate, characterization, antibacterial effect, acute toxicity, pharmacokinetics

Isotactic poly (1-butene) (iPB) has excellent properties which are recognized as a green and energy saving product. However, the most stable and valuable crystal form I had a spontaneous transformation that took as long as seven days to complete. As a special solid waste, the herb residue (HR) is rich in cellulose which has great potential to accelerate the crystal transformation of the iPB. However, the polarity of HR results in the interface compatibility with non-polar iPB. In this study, the HR was modified by silane coupling agent (KH570) to obtain KHR and the iPB/HR composite was prepared. The FTIR spectrum was indicated that the organic functional groups of KH570 successfully graft onto the surface of HR and the water contact angle test was indicated that the hydrophilicity of the KHR was greatly decreased. The complete crystal transformation time is 7 days for iPB, 6 days for iPB+5% HR but only 3 days for iPB+5% KHR. The addition of the HR and KHR improve the thermal stability of the composite and this beneficial effect is more obvious for KHR. After annealing for 5 days, the physical properties value include tensile strength, flexural strength, and HDT of iPB+5% HR reach that of pure iPB after annealing for 7 days, but only 3 days for iPB+5% KHR. The TG analysis and SEM photographs give clear evidence that the beneficial effect of KH570 modified HR on improving the interface compatibility with iPB.

Isotactic polybutylene-1 (iPB) has lots of advantages and is best used as hot water pipe. However, to transform into stable crystal form I, the iPB needs as long as 7 days. In this process, the irreversible damage brings great difficulties to the use of the iPB. The method which convert it directly into crystal I has shortcomings such as being requiring complex operation and being expensive. In this study, an innovative idea was put forward, not paying attention to the crystal transformation of iPB but only focusing on reducing the time it can be applied. In this study, bamboo powder was modified by the silane coupling agent KH570 (KBP) to prepare iPB/KBP composite. The infiltration test and Fourier transform infrared (FTIR) analysis showed that the hydrophilicity of KBP is greatly reduced, which can greatly improve the compatibility of the iPB and KBP. The tensile strength, tensile modulus, flexural strength, and flexural modulus of the composites storage for 3 days is equal to the pure iPB with storage 7 days with the KBP additions of 3%, 3%, 7%, and 5%, respectively. The heat deformation temperature (HDT) of the composite with 3% KBP after 1-day storage reached the value of pure iPB storage for 7 days. This provides more space and possibilities for the industrialization of the iPB. The crystallization behavior of iPB/KBP composites proves that the addition of KBP accelerates the crystallization rate of iPB, but the crystallinity of the iPB/KBP composites is not changed. The SEM photograph of iPB/KBP composites showed that when the KBP addition was low the compatibility between KBP and iPB was good. When the KBP addition was increased the agglomeration of KBP in the iPB was very obvious, which leads to the poor mechanical properties of the composite.

Isotactic polypropylene (iPP) is a commonly used thermoplastic polymer with many excellent properties. But high brittleness, especially at low temperatures, limits the use of iPP. The presence of transcrystallization of iPP makes it possible for fiber-reinforced iPP composites with higher strength. Bacterial cellulose (BC) is a kind of cellulose with great potential to be used as a new filler to reinforce iPP due to its high crystallinity, biodegradability and efficient mechanical properties. In this study, the iPP/BC hamburger composite was prepared by a simple hot press and maleic anhydride grafted polypropylene (MAPP) was used to improve the interface compatibility of iPP and BC. The polarizing microscope (POM) photograph shows that BC successfully induces the transcrystallization of iPP. The differential Scanning Calorimeter (DSC) date proves that the addition of BC could improve the thermal properties and crystallization rate of the composite. Especially, this change is more obvious of the iPP/MAPP/BC. The mechanical properties of the iPP/BC composites were greatly increased. This DSC date is higher than BC, we used BC particles to enhance the iPP in our previous research. The scanning Electron Microscope (SEM) analysis intuitively shows that the interface of the iPP/MAPP/BC is more smooth and flat than the iPP/BC. The fourier Transform infrared spectroscopy (FT-IR) analysis of the iPP/BC hamburger composites was shown that a new C=O group vibration appeared at 1743 cm&minus, 1, which indicated that the hydrogen bond structure of BC molecules was weakened and some hydroxyl groups were substituted after modification which can increase the lipophilicity of BC. These results indicated that the BC fiber can easily induce the transcrystallization of iPP, which has excellent mechanical properties. Moreover, the addition of MAPP contributes greatly to the interface compatibility of iPP and BC.

Bacterial cellulose (BC) is a new kind of cellulose with great potential in enhancing preparation of isotactic Polypropylene (iPP) composites, which have been found with excellent performance. However, the interface compatibility between BC and iPP is poor. In this study, iPP/BC composites were prepared by solution mixing. Esterification modified BC (CO) and Maleic anhydride grafted polypropylene (MAPP) added as a compatibilizer was both used to improve the interfacial compatibility of the iPP/BC composites. The rheology and isothermal crystallization behavior of the composites was tested and discussed. The result shows that the complex viscosity and storage modulus of the composite significantly increase in the rule iPP, iPP/BC2, iPP/CO2, and M-iPP/BC3, which indicates that the compatibility of the composite increases as this rule. According to the isothermal crystallization kinetics result, the crystal growth mode of iPP was not affected by the addition of BC and the interfacial compatibility. The spherulite growth rate of the iPP/BC composite increases with increasing crystallization temperature. Especially, the value decreases as the same rule with the complex viscosity and storage modulus of the composite at the same isothermal crystallization temperature. These results suggest that the interface compatibility of iPP/BC composites is greatly improved and the interface compatibility of the M-iPP/BC3 is better than the iPP/CO2.

summary Research into synthetic streamflow generation previously focused primarily on engineering purposes, while disregarding hydro-ecological implications with regard to daily flow. This study investigated the applicability of daily synthetic flow models in the representation of hydro-ecological characteristics. This study applied flow duration curves and three performance indices as well as a method of statistical testing to identify whether Indicators of Hydrologic Alteration (IHA) derived from historical and synthetic flow data have the same distribution. This enabled us to evaluate the capacity of the synthetic flow models in capturing other important hydrological characteristics. This study examined various representative methods, most of which proved effective in simulating the magnitude of monthly flow and high flow within short durations. However, low flow conditions remain problematic, particularly over short durations. Among the various models, annual flow simulation using annual–daily disaggregation demonstrated good reproducibility, but its applicability with regard to within year fluctuations may be limited by the relatively low degree of freedom. Direct simulation models (shot noise and Markov-based) proved suitable in dealing with engineering problems based on monthly averages and annual daily maximum flow. Linear regression models, PARMA, and nonparametric models, modified k-NN, were shown to be well-suited to the representation of monthly stream flow. In conjunction with nonparametric bootstrap disaggregation, these methods proved effective in representing daily flow patterns. Coupling these methods with the shot noise disaggregation model was the least recommended due to bias resulting from numerical errors associated with repeated convolutions. 2014 Published by Elsevier B.V.

Cefquinome Sulfate (CS) is a fourth-generation cephalosporin, which has been developed solely for veterinary use. It shows potent antibacterial activity against a broad spectrum of bacterial species. However, Cefquinome is susceptible to hydrolysis, which limiting its clinical employment efficacies to some extent. So, in this study, to increase Cefquinome Sulfate biological half-life, a novel Cefquinome Sulfate proliposome was prepared by solid dispersion and effervescent techniques and characterized for morphology, particle size, entrapment efficiency and in vitro release. A Reversed Phase-High Performance Liquid Chromatography (RP–HPLC) method was first chosen and established to determine the drug concentration in plasma after intra muscular (IM) administrating Cefquinome Sulfate solution and liposome at a single dosage of 18 mg/kg in rabbit. Then their pharmacokinetics in vivo was compared. Results showed that the received liposome was milky white suspension, spherical or ellipsoidal in shape. The mean particle size was 203±5 nm and the entrapment efficiency was 53.5±0.16%. The cefaquinom sulfate solution and liposome both followed a two compartment model, in vivo. The pharmacokinetic parameters for the solution and liposomal formulations were measured as follows: t1/2α were (1.214 ± 0.135) h and (1.395 ± 0.113) h, t1/2β were (8.752 ± 0.846) h and (16.503 ± 1.275) h, AUC(0-24) were (49.582 ± 9.173) (mg·h)/L and (138.727 ± 11.034) (mg·h)/L, CL/F were (0.357 ± 0.015) L/(h·kg) and (0.127 ± 0.012) L/(h·kg), MRT(0-24) were (2.68 ± 0.229) h and (5.945 ± 0.479) h, respectively. It could be clearly seen that t1/2β of liposome prolonged (p < 0.05), AUC and MRT both increased remarkably (p < 0.01), CL/F decreased. Results indicated that this preparation has more residence time and exhibits some sustained–release tendency.

Mechanical property of coating under the micro-contact load such as impact and sliding wear significantly influence the reliability of surface coating. In order to research the influence, a contact model between the rigid multi-asperity surface and coating was found based on the G-W model in the background of Thermal Barrier Coatings(TBCs) used in aircraft engine blade. The distribution of stress in subsurface of the micro-contact process was analyzed based on the theories of contact mechanics and tribology with the elasto-plastic finite element method. The effect of coating thickness, elastic modulus, yield strength on the distribution of residual stress for TBCs was investigated. It conclude that primary reason of coating failure are cumulation of plastic deformation and excessive interfacial stress. The results are significant for studying the life and final spallation of TBC system and other coating.