Sequestration patterns of transfused rat neutrophilic granulocytes under normal and inflammatory conditions

Abstract: The fate of polymorphonuclear neutrophilic granulocytes (PMN) after their mobilization from the bone marrow of healthy individuals is not clearly understood. It has been suggested that there is a continuous utilization of these cells in widespread, subclinical inflammatory foci, where they are ultimately degraded. The goal of the present experiments was to determine whether an alternative ecotaxis (“homing”) exists, namely sequestration and degradation of PMN by mononuclear phagocytes exposed to the bloodstream in the liver, spleen and bone marrow. Blood PMN were collected from donor rats, labelled with ⁵¹Cr, and injected i.v. into 2 syngeneic rats, one of them having an induced sterile peritonitis. After various time intervals up to 18 h, the rats were killed and exsanguinated. As expected, we found cell-bound radioactivity in the inflamed peritoneal cavities, and also a high amount of radioactivity in liver, spleen, and bone marrow. The bone marrow uptake of PMN appeared to be much lower in the inflammation rats than in the normal controls. These findings were confirmed in PMN transfer experiments using PVG rats congenic for the RT7 alloantigenic system. Here, transfused blood leukocytes were traced with fluorescent, monoclonal HIS41 antibodies and flow cytometry. A possible corticosteroid effect on the bone marrow sequestration could not be substantiated. Uptake and degradation of PMN takes place in organs containing phagocytes exposed to the bloodstream. Sequestration of PMN in the bone marrow is apparently down-regulated in inflammatory states, perhaps increasing the PMN availability to inflamed tissue.     

Cr:LiSAF激光在组织自体荧光光谱研究中的应用

目的　该文以Cr:liSAF激光作为激发光源 ,针对生物大分子设计了荧光实验 ,以探讨其在组织自体荧光研究中的应用。方法　氙灯泵浦Cr:LiSAF二次谐波用来产生可调谐蓝光脉冲激光输出 ,并设计了自体荧光试验。结果　最后设计并实现了可调谐蓝光脉冲激光输出 ,得到了良好的输出特性。结论　氙灯泵浦Cr:LiSAF二次谐波产生可调谐蓝光脉冲激光输出得到了良好的输出特性 ,该实验为进一步研究肿瘤组织与正常组织自体荧光产生机制打下了基础。     

Nanofused Hierarchically Porous MIL-101(Cr) for Enhanced Methyl Orange Removal and Improved Catalytic Activity

Hierarchically porous MIL-101(Cr) (H-MIL-101(Cr)) with meso/macro-pores was directly prepared via nanofusion progress by using butyric acid as a modulating agent. In the methyl orange (MO) adsorption experiments, H-MIL-101(Cr) showed a high adsorption capability of 369.8 mg g⁻¹, which was 1.52-fold greater than that of pristine MIL-101(Cr) (P-MIL-101(Cr)). While in the oxidation reaction of indene and 1-dodecene tests, H-MIL-101(Cr) presented much higher catalytic efficiency, with turnover frequency (TOF) values of 0.7242 mmol g⁻¹ min⁻¹ and 0.1492 mmol g⁻¹ min⁻¹, respectively, which were 28% and 34% greater than that in the case of P-MIL-101(Cr). Thus, compared with P-MIL-101(Cr), H-MIL-101(Cr) exhibited better removal efficiency and higher levels of activity in the oxidation reactions of indene and 1-dodecene. The unique structure of H-MIL-101(Cr) also contributed to its superior performance in these processes.     

Study on Hot Deformation Behavior of an Antibacterial 50Cr15MoVCu Tool Steel

Hot deformation behaviors of an antibacterial 50Cr15MoVCu tool steel were studied. The flow stress curves presented three typical characteristics: (i) a single peak dynamic recrystallization curve, (ii) a monotone incremental work-hardening curve, and (iii) the equilibrium dynamic recovery curve. The flow stress increased with the increase of the deformation rate at each deformation temperature and decreased with the increase of the deformation temperature at the same deformation rate. The thermal activation energy and material constants were Q of 461.6574 kJ/mol, A of 3.42 × 10¹⁷, and α of 0.00681 MPa⁻¹, respectively. The high temperature constitutive equation was: Z=ε˙expQ/RT=3.42×1017sinh0.0068×σ5.6807. Based on the processing maps and microstructure evolution, the best hot working process was a deformation temperature of 1050 °C and deformation rate of 0.001 s⁻¹.     

Anti-osteoporotic effect of Erythrina variegata L. in ovariectomized rats

The present study was designed to investigate whether Erythrina variegata L. (EV), which belongs to the leguminous family, exerted any beneficial effects on bone in ovariectomized rats. Daily oral administration of the EV extract at 300 and 600 mg/kg for 14 weeks to rats prevented the OVX-induced increase in the serum OCN, ALP, and urinary DPD levels. Histomorphometric analysis of the proximal end of the tibia showed that the EV extract prevented the estrogen deficiency-induced decrease in trabecular thickness and trabecular area, as well as restoring the increase in trabecular separation in a dose-dependent manner. Moreover, the EV extract improved the energy absorption and stiffness of the mid-shaft of the rat femur. Thus, the present study clearly demonstrated that EV could suppress the high rate of bone turnover induced by estrogen deficiency, inhibit bone loss and improve the biomechanical properties of bone in the OVX rats.     

Size-Dependent Persistent Luminescence of YAGG:Cr3+ Nanophosphors

In the current work, YAGG:Cr³⁺ nanophosphors were synthesized by the Pechini method and then annealed at different temperatures in the range 800–1300 °C. The structure and morphology of the samples were characterized by X-ray Powder Diffraction (XRPD). The lattice parameters and average crystalline sizes as site occupation by Al³⁺ and Ga³⁺ ions were calculated from the Rietveld refinement data. To investigate the effect of crystalline size of the materials on their optical properties: excitation and emission spectra were recorded and analyzed. Finally, the effect of crystalline size on the probability of carrier recombination leading to PersL was determined experimentally with thermoluminescence analyses. The T_max-T_stop method was applied to determine the trap type and particle size (calcination temperature) effect on their redistribution. A correlation between structural changes and trap redistribution was found. In particular, the extinction of high-temperature TL maximum with increasing annealing temperatures is observed, while low-temperature TL maximum increases and reaches a maximum when the lattice parameter reaches saturation.     

血胱抑素C及尿酶对糖尿病肾病早期诊断的意义

目的探讨血胱抑素C(CysC)、尿N-乙酰-β-D-氨基葡萄糖苷酶(NAG)、尿微量白蛋白(mALB)对糖尿病肾病早期诊断的临床意义。方法选择我院60例糖尿病患者,其中尿蛋白阴性的患者31例为观察1组,阳性29例为观察2组;同时选择体检中心同期同年龄段正常体检者40例为对照组,测定糖尿病组和正常对照组血胱抑素C(CysC)、尿N-乙酰-β-D-氨基葡萄糖苷酶(NAG)、尿微量白蛋白(mALB),同时测定尿肌酐(Cr)。结果分别以CysC、NAG/Cr、mALB/Cr表示。结果观察1组与观察2组CysC、NAG/Cr、mALB/Cr指标明显高于对照组,检测结果比较差异明显,具有统计学意义P<0.05;观察2组CysC、NAG/Cr、mALB/Cr指标明显高于观察1组,2组结果比较差异明显,具有统计学意义P<0.05。结论 CysC、NAG/Cr、mALB/Cr能较准确反应早期糖尿病患者肾损害程度的临床检测指标,三者联合检测是早期诊断糖尿病肾病的敏感指标。     

Er,Cr:YSGG激光联合粘结剂封闭牙本质小管的封闭效果

目的 通过扫描电镜观察,定量评估并比较自酸蚀粘结剂、Er,Cr:YSGG激光及其联合应用对牙本质小管的封闭效果.方法 将40颗人新鲜拔除的第三磨牙制备成1.5 mm厚的牙本质片,用35%磷酸处理10 s,采用简单随机分组法将标本随机分为四组:A组为空白对照组,不做任何处理;B组和C组为自酸蚀粘结剂组和Er,Cr:YSGG激光组,分别用Clearfil S3 Bond自酸蚀粘结剂和Er,Cr:YSGG激光进行表面处理;D组为Er,Cr:YSGG激光联合粘结剂组,先用Er,Cr:YSGG激光进行表面照射,后用自酸蚀粘结剂进行表面处理,扫描电镜下观察各组牙本质表面及纵剖面的超微结构.结果 (1)表面结构:A组牙本质小管口全部开放,清晰无玷污层;B组牙本质小管口表面覆盖大量晶体状结晶物,牙本质小管口明显缩窄;C组牙本质小管口表面呈凹凸不平的熔融状,牙本质小管口不规则地向管中心缩窄;D基本看不到牙本质小管口,牙本质表面覆盖有一层均匀的细结晶物.(2)纵剖面结构:A组牙本质小管呈条索状平行排列,小管内光滑无堵塞物;B组牙本质小管内可见长条状的致密树脂突堵塞物;C组牙本质小管内堵塞物进入牙本质小管深度较浅;D组牙本质小管内可见白色细条索状堵塞物,外部为一层均匀致密物质.(3)组间牙本质小管直径和面积比较,空白对照组>粘结剂组>激光组>联合组,组间牙本质小管堵塞率比较,联合组>激光组>粘结剂组,差异均有统计学意义(P<0.05).结论 自酸蚀粘结剂,Er,Cr:YSGG激光,以及两者联合应用均能有效封闭牙本质小管,且联合组优于单独应用.     

氢质子核磁共振波谱分析在颞叶癫痫患者中的应用价值

目的观察颞叶癫痫患者颞叶NAA、Cr和Cho代谢物质的变化及这些变化在癫痫发病中的意义。方法颞叶癫痫患者25例为病例组,健康体检者22例为正常对照组,行颞叶^1H-MRS检查。结果颞叶组NAA／（Cr＋Cho）比值明显低于对照组（P〈0．01）.结论颞叶癫痫患者脑组织中NAA强度下降,Cho、Cr升高,有助于癫痫的病理生理基础研究。     

Preparation and Characterization of Magnetite Talc (Fe3O4@Talc) Nanocomposite as an Effective Adsorbent for Cr(VI) and Alizarin Red S Dye

In this work, the adsorption of Cr(VI) ions and the organic dye Alizarin Red S (ARS) was investigated using magnetite talc (Fe₃O₄@Talc) nanocomposite. Different characterization techniques such as scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), and thermogravimetric analysis (TGA) were used to demonstrate the physical and chemical properties of the fabricated Fe₃O₄@Talc nanocomposite. In addition, the adsorption isothermic, kinetic, and thermodynamic properties were illustrated. The results demonstrate that the investigated adsorption processes obeyed the Langmuir isotherm model for Cr(VI) and the Freundlich isotherm model for ARS dye, with a maximum adsorption capacity of 13.5 and 11.76 mg·g⁻¹, respectively, controlled by pseudo second-order kinetics. Regeneration and reusability studies demonstrated that the prepared Fe₃O₄@Talc nanocomposite is a promising and stable adsorbent with considerable reusability potential.