甲状腺激素对小鼠面神经损伤轴突再生及神经电生理功能的影响

目的： 探讨甲状腺激素对小鼠面神经损伤轴突再生及神经电生理功能的影响。方法： 将64只小鼠随机分为4组,即假手术组、模型组、甲状腺素组、甲状腺素+LY组,每组16只。除假手术组外,其余组均建立面神经损伤模型。术后苏醒开始干预,甲状腺素组于损伤处皮下注射50 μg/kg中性甲状腺素溶液,甲状腺素+LY组在甲状腺素组基础上腹腔注射600 μg/kg PI3K/AKT通路抑制剂LY294002,假手术组和模型组于损伤处注射生理盐水,每天1次,持续2周。干预结束后进行神经电生理检测,锇酸染色进行再生轴突计数,Western免疫印迹法检测面神经组织中p-AKT、NGF、BDNF蛋白的表达。采用SPSS 21.0软件包对数据进行统计学分析。结果： 假手术组正常神经髓鞘外未见新生轴突。与模型组相比,甲状腺素组和甲状腺素+LY组再生轴突数均升高,甲状腺素组显著高于甲状腺素+LY组（P<0.05）。与假手术组相比,模型组运动神经传导速度（MNCV）和波幅降低,潜伏期延长（P<0.05）;与模型组相比,甲状腺素组和甲状腺素+LY组MNCV、波幅升高,甲状腺素组显著高于甲状腺素+LY组（P<0.05）;与模型组相比,甲状腺素组和甲状腺素+LY组潜伏期缩短,甲状腺素组显著短于甲状腺素+LY组（P<0.05）。与假手术组相比,模型组p-AKT、NGF、BDNF蛋白相对表达量显著升高（P<0.05）;与模型组相比,甲状腺素组p-AKT蛋白相对表达量显著升高,甲状腺素+LY组显著降低（P<0.05）;与模型组相比,甲状腺素组和甲状腺素+LY组NGF、BDNF蛋白相对表达量升高,甲状腺素组显著高于甲状腺素+LY组（P<0.05）。结论： 甲状腺激素可有效促进小鼠面神经损伤轴突再生,改善神经电生理功能,其机制可能是通过促进AKT磷酸化而发挥调控作用。     

胆钙化醇灭鼠剂的研究

长期高强度的施用抗凝血灭鼠剂,家栖鼠已经出现较大范围的拒食和耐药现象,需要研发一种可以有效克服抗凝血灭鼠剂耐药性或抗药性的新型灭鼠剂。胆钙化醇灭鼠剂(cholecalciferol)是一种安全性好、可以防治对抗凝血灭鼠剂产生抗药性鼠的新型灭鼠剂,在美国、新西兰等发达国家得到广泛应用。本文综述了胆钙化醇灭鼠剂的毒力、现场灭效、适口性及对抗药鼠灭效等国内外研究进展,以此展望胆钙化醇灭鼠剂在我国的应用潜力。     

三阴性乳腺癌用药进展

三阴性乳腺癌是缺乏雌激素受体、孕激素受体和人类表皮生长因子受体-2的特殊类型的乳腺癌，相比其他乳腺癌亚型，其临床特征为预后较差、高侵袭性、高转移性以及高复发率。目前三阴性乳腺癌的早期治疗手段主要为蒽环类和紫杉烷类化学疗法，但容易产生耐药性；而且三阴性乳腺癌对一些现有的靶向药物和内分泌治疗药物敏感性也不高。因此本文在介绍目前三阴性乳腺癌涉及的临床用药的基础上，还对联合用药、新药研发进展作简要综述，为今后的用药提供思路。     

The application of subspace preconditioned LSQR algorithm for solving the electrocardiography inverse problem

Regularization is an effective method for the solution of ill-posed ECG inverse problems, such as computing epicardial potentials from body surface potentials. The aim of this work was to explore more robust regularization-based solutions through the application of subspace preconditioned LSQR (SP-LSQR) to the study of model-based ECG inverse problems. Here, we presented three different subspace splitting methods, i.e., SVD, wavelet transform and cosine transform schemes, to the design of the preconditioners for ill-posed problems, and to evaluate the performance of algorithms using a realistic heart-torso model simulation protocol. The results demonstrated that when compared with the LSQR, LSQR-Tik and Tik-LSQR method, the SP-LSQR produced higher efficiency and reconstructed more accurate epcicardial potential distributions. Amongst the three applied subspace splitting schemes, the SVD-based preconditioner yielded the best convergence rate and outperformed the other two in seeking the inverse solutions. Moreover, when optimized by the genetic algorithms (GA), the performances of SP-LSQR method were enhanced. The results from this investigation suggested that the SP-LSQR was a useful regularization technique for cardiac inverse problems.     

IgE- and T-lymphocyte-Dependent Hypersensitivity Responses Induced in Mice by Exposure to Shrimp (Fenneropenaeus chinensis) Proteins

Shellfish allergy is a common cause of food-induced anaphylaxis in the human, and shrimp is one of the most frequently reported causes of allergic reactions. To identify the immunoglobulin E (IgE)-binding proteins of Chinese shrimp (Fenneropenaeus chinensis), the crude extracts were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS–PAGE) and Western blotting. After exposure of shrimp extracts to mice, the levels of shrimp allergen-specific IgE were determined by indirect ELISA. Histological and immunohistochemical staining of intestinal tract were further performed for immunological analysis. IgE-binding components with molecular masses of 40, 37, 28, 22, and 20 kDa at a high frequency are supposed to be major allergens of F. chinensis. In vivo experiments showed that shrimp extracts could lead to allergen-specific IgE reactivity, and increase mast cell degranulation and numbers of T lymphocytes. IgE- and T-lymphocyte-dependent hypersensitivity plays important roles in allergic reactions triggered by F. chinensis allergens.     

Renewable juglone nanowires with size-dependent charge storage properties

Inspired by the biological metabolic process, some biomolecules with reversible redox functional groups have been used as promising electrode materials for rechargeable batteries, supercapacitors and other charge-storage devices. Although these biomolecule-based electrode materials possess remarkable beneficial properties, their controllable synthesis and morphology-related properties have been rarely studied. Herein, one dimensional nanostructures based on juglone biomolecules have been successfully fabricated by an antisolvent crystallization and self-assembly method. Moreover, the size effect on their electrochemical charge-storage properties has been investigated. It reveals that the diameters of the one dimensional nanostructure determine their electron/ion transport properties, and the juglone nanowires achieve a higher specific capacitance and rate capability. This work will promote the development of environmentally friendly and high-efficiency energy storage electrode materials.

Renewable juglone nanowires have been successfully fabricated, and their size effect on electrochemical charge-storage properties has been investigated.

Currently, the development of high-performance electrochemical energy-storage materials and devices is attracting intensive interest. Conventional electrode materials involving transition metal compounds,^1–4 elementary substances,^5–8 and conductive polymers,^9–12 with superior charge storage properties have been widely investigated. However, the poor biocompatibility, rising prices and depletion issues limit their sustainable applications due to their intrinsic material properties.¹³ Thus, exploring naturally abundant and renewable charge-storage materials with promising electrochemical performance is of great significance.In the biological system, its metabolic process mainly relies on ions transport and energy exchanges of redox-active biomolecules with special functional groups such as carbonyl groups, carboxyl groups, and pteridine centres.¹⁴ Due to their abundance, sustainability, environmental benignity, these renewable and nature-derivable biomolecules with well-defined charge-storage behaviors are ideal alternatives to conventional electrode materials for the next-generation green energy-storage devices.^15–17 For instance, biomolecules such as lignin,¹⁸ melanin,¹⁹ riboflavin,²⁰ juglone²¹ and humic acid²² have been demonstrated as promising electrode materials for the rechargeable batteries, supercapacitors and other charge-storage devices. Although these biomolecule-based electrode materials possess remarkable beneficial properties, they are still confronted with several serious problems of poor conductivity and high electrochemical reaction impedance.²³ For some conventional inorganic and organic active electrode materials, decreasing their size has been demonstrated to be effective strategies to enhance the electrochemical reaction kinetics by exposing more active sites to electrolytes and conductive agent.^8,24,25 These results have strongly motivated us to develop biomolecule-based nanostructures, and investigated their size-correlative charge storage behavior.^26,27Herein, one dimensional (1D) nanostructures based on juglone, a renewable redox-active biomolecule which can be derived from matured fruits of black walnut and the green peel of juglandaceae, have been successfully fabricated by an antisolvent crystallization and self-assembly method.^28–30 The size effect on the electrochemical charge-storage properties of these biomolecule-based 1D nanostructures have been investigated. It reveals that the electronic/ionic transport properties and charge-storage performance can be modulated by the size of self-assembled 1D nanostructures, and the samples with smaller diameter realize the higher specific capacitance and rate capability. Our work will provide insights for the development of high-performance biomolecule-based green energy-storage materials and devices.Juglone, also called 5-hydroxy-1,4-naphthalenedione, is a nature-derivable biomolecule, and displays a well-defined redox behavior in acetonitrile due to its quinone groups (Fig. 1a and b).³¹ As organic molecule inherently, it is soluble in organic solvent and difficult to dissolve in water, so its nano-architectures could be condonably fabricated by an antisolvent crystallization strategy (Fig. 1c) and would carry out stably for charge storage in an aqueous electrolyte.^29,30 Firstly, the juglone-biomolecule-based 1D nanostructures with different size were synthesized. The juglone micropillars with a mean diameter around 12 μm were prepared by directly recrystallizing a water/acetonitrile mixed solution of juglone at room temperature (Fig. 2a and d). Compared to commercially available raw juglone materials (Fig. S1^†), the juglone micropillars could increase its charge storage performance, but its relative large size would still confine its contact with electrolyte, and thus remarkably reduce the reaction kinetics.³² To further improve the potential reaction kinetics, the juglone microwires with an average diameter about 1 μm (Fig. 2b and e) and juglone nanowires with a mean diameter about 550 nm (Fig. 2c and f) were fabricated at room temperature using the reprecipitation method.³³ In the specific synthesis process, a high-concentration juglone acetonitrile solution is injected into water, which is a poor solvent for juglone molecules. Under stirring, juglone started to crystallize within a few seconds owing to its poor solubility in the water/acetonitrile mixture solvent and self-assembled into 1D nanostructures, and this procedure could be resulted from the π–π interaction.²⁹ It can be found that the diameter of 1D juglone materials is adjustable by tuning the concentration of juglone in acetonitrile, and the higher concentration of juglone acetonitrile solution yields the smaller size of 1D juglone materials. The insert panels show the percentage of juglone micropillar, microwire, nanowire with different diameter coverage (Fig. 2d–f).Open in a separate windowFig. 1(a) Chemical structural formula of juglone biomolecules which can be derived from the bark of black walnuts. (b) Juglone redox activity verified in a mixed solution of acetonitrile/deionized water by a three-electrode system using Pt foils as both the counter and working electrodes, Ag/AgCl as the reference electrode, and 2.3 M H₂SO₄ as the electrolyte. (c) Schematically illustration of the fabrication of the juglone nanowire/microwire.Open in a separate windowFig. 2SEM images of juglone 1D nanostructures at different magnification. (a and d) Juglone micropillar, (b and e) juglone microwire, (c and f) juglone nanowire. The insert images in panels (d–f) are corresponding mathematical statistic results of juglone samples with different diameter.Generally, the covalent bond, hydrogen bond, van der Waals forces, electrostatic forces, surface tension forces/dewetting, and π–π stacking interactions are considered as the effective factors in the self-assembly procedure of organic compounds.^34–36 The juglone biomolecule has a α-naphthol backbone with two carbonyl groups, which may induce the molecules self-assembly by the π–π interactions.^29,37–39 Fourier Transform Infrared Spectroscopy (FTIR) of such samples was utilized to examine the ingredient of these samples. As shown in Fig. S2,^† all the samples show similar characteristic peaks, the peak at 1640 cm⁻¹ is attributed to the stretching vibration of carbonyl groups, which is the main reversible redox center presented in juglone molecules. Meanwhile, Raman spectra also corroborated the results (Fig. S4^†). The crystal structures of these samples are further characterized by X-ray diffraction (XRD) as shown in Fig. S3.^† No impurity peak is observed in these patterns, demonstrating that these samples have the same crystal structure. And the peak intensity of juglone nanowire is stronger than juglone microwire and micropillar, suggesting that juglone nanowires have high crystallinity and relatively uniform crystal size.³⁰To investigate the redox behavior of 1D juglone micro/nanostructures, the cyclic voltammetry (CV) measurements were firstly performed (Fig. 3a), and the result reveals that these samples show a superior reversible redox performance, implying a potential application as energy storage materials. Meanwhile, compared with the CV curves of raw juglone, juglone micropillar and juglone microwire, the juglone nanowire exhibits the strongest redox peak, suggesting that the juglone nanowire-based electrode has a better charge storage behavior. To further evaluate the electrochemical performance of these samples, galvanostatic charge–discharge (GCD) measurements were carried out (Fig. 3b). First, juglone nanowire shows a higher specific capacity than that of microwire and micropillar. Besides, the plot of juglone 1D-based electrodes exhibit symmetric triangular shape with one pair of charge–discharge voltage plateau, and the voltage plateau of juglone micropillar, microwire and nanowire appears at 0.28 V, 0.26 V, 0.22 V, which is roughly consistent with the results of CV curves. Furthermore, it further reveals that the 1D nanostructure with smaller size exhibits higher specific capacity during the scan rates increasing from 10 to 200 mV s⁻¹ (Fig. 3c). In detail, at a low scan rate of 10 mV s⁻¹, the specific capacity delivered by juglone nanowire, juglone microwire, juglone micropillar are 389 F g⁻¹, 375 F g⁻¹, 116 F g⁻¹, respectively, and these samples possess the specific capacities of 232 F g⁻¹, 205 F g⁻¹, 80 F g⁻¹, when the scan rate are enhanced to 200 mV s⁻¹. The general perception is that nanomaterials with higher specific surface areas usually possess better electrochemical performance.⁴⁰ Obviously, the higher specific capacitance and superior rate capability are achieved by juglone nanowire electrode.Open in a separate windowFig. 3Electrochemical performance of the juglone samples with different diameter. (a) CV curves of juglone micropillar, microwire, nanowire electrodes in the potential range of −0.1 to 0.7 V (vs. Ag/AgCl) with a scan of 50 mV s⁻¹, (b) galvanostatic charge–discharge curves of juglone electrodes with different diameter at 2 A g⁻¹. (c) Statistical study of the rate performance conducted at each scan rate based on the cyclic voltammetry capacity of five electrodes as one batch. (d) Impedance phase angle as a function of frequency for juglone micropillar, microwire, nanowire electrodes. Inset is the Nyquist plot of them. (e) Correlation between the diameter and the specific capacity of the juglone samples at various scan rates.Then, the reaction kinetics of juglone with different sizes were investigated by electrochemical impedance spectroscopy (EIS) (Fig. 3d and S5^†). The crooked curve at high frequency denotes the interface resistance, involving contact and charge transfer resistances, while the low-frequency line represents ion diffusion resistance. The interface resistances of juglone nanowire, microwire, micropillar, raw material electrodes are 3.45 Ω, 3.80 Ω, 3.95 Ω, 4.02 Ω. The plot of the phase angle against the frequency reveals the characteristic frequency f₀ at the phase angle of −45° is 7.46 Hz for juglone nanowire-based electrode, and it is relatively higher than that for juglone microwire (7.36 Hz), micropillar (7.25 Hz) and raw material (6.48 Hz). Accordingly, the time constant t₀ (t₀ = 1/f₀) that represents the minimum time to discharge ≥50% of all the energy from the electrode was 0.134 s for juglone nanowire, whereas 0.136 s, 0.138 s, 0.154 s were required for juglone microwire, micropillar and raw material. The low charge transfer resistance, and short time constant validated the excellent charge and discharge capability of the juglone nanowire-based electrode.⁴¹In addition, for solid-state diffusion of H⁺ in electrode materials, the mean diffusion time is proportional to the square of the diffusion path length according to the following equation:t ≈ L²/D_H⁺1where L is the diffusion length and D_H⁺ the diffusion constant.^42,43 It has been found that the diffusion pathway will be shortening by nanostructuring of electrode materials when the diffusion constant D is same,⁴⁴ indicating that the smaller size nanostructures of juglone facilitate rapid ion/electron transport. Thus, 1D juglone nanowires possess higher specific capacitance and show slower capacity decay during the increased scan rates (Fig. 3e).Furthermore, the CV and GCD for juglone nanowire-based electrodes were tested under various scan rates and current densities. The CV profiles show that the redox activity can be maintained very well when increasing the scan rate from 10 to 100 mV s⁻¹ (Fig. 4a). Moreover, the GCD curves collected at different current densities exhibit symmetric triangular shape with one pair of charge–discharge voltage plateau, which is similar to the results of CV test (Fig. 4b and c). And the specific capacity is 342 F g⁻¹ at a current density of 2 A g⁻¹, it is approximately equivalent to the 345 F g⁻¹ at a scan rate of 20 mV s⁻¹. Next, the specific capacitance of our juglone nanowire is further compared to those of the reported conventional electrode materials.^45–51 As shown in Fig. 4d, the capacity of N/rGO (reduced graphene oxide doping with nitrogen) is 138 F g⁻¹, and our juglone nanowire have about 2-fold higher specific capacity than N/rGO, 1.5-fold higher than Fe₃O₄/rGO (154 F g⁻¹).Open in a separate windowFig. 4(a) CV curves of the juglone nanowire electrode at different scan rates from 10 mV s⁻¹ to 100 mV s⁻¹. (b) Charge and discharge curves in the current density range from 2 A g⁻¹ to 10 A g⁻¹. (c) Various specific capacity of the juglone nanowire electrode when increasing the scan rate from 10 mV s⁻¹ to 200 mV s⁻¹. (d) Specific capacity of juglone nanowire in comparison with different materials.     

Adsorption activity of coconut (Cocos nucifera L.) cake dietary fibers: effect of acidic treatment,cellulase hydrolysis,particle size and pH

The effects of acidic treatment, cellulase hydrolysis, particle size distribution and pH on the adsorption capacity of defatted coconut cake dietary fibers (DCCDF) were studied. The results demonstrated that cellulase hydrolysis could significantly improve the soluble dietary fiber content, water holding ability and adsorption ability of DCCDF on cholesterol, bile and nitrite ions. Acidic treatment enhanced the oil holding capacity and adsorption ability in cholesterol and nitrite ions. Moreover, the adsorption ability of DFs in cholesterol, nitrite and bile all increased with reduced particle size (250 to 167 μm), and DCCDF demonstrated a higher adsorption capacity at pH 2.0 than at pH 7.0. The change in adsorption capacity of DCCDF might be suitable for application in the food industry as a low-calorie and cholesterol lowering functional ingredient.

This paper provides valuable information on the effects of cellulase hydrolysis, acidic treatment, particle size distribution and pH on the adsorption activity of coconut cake dietary fibers.