Effects of polyethylene glycol content on the properties of a silk fibroin/nano-hydroxyapatite/polyethylene glycol electrospun scaffold

To study the effects of polyethylene glycol (PEG) content on the mechanical properties and degradation of silk fibroin, nano-hydroxyapatite, and PEG (SF/nHAP/PEG) electrospun scaffolds, and according to the PEG ratio in the scaffold (SF : nHAP : PEG), test groups were divided as follows: PEG-0 (10 : 2), PEG-0.5 (10 : 2 : 0.5), PEG-1 (10 : 2 : 1), and PEG-2 (10 : 2 : 2). A series of tests to determine the mechanical properties, degradation rates, and osteogenic characteristics was undertaken. PEG facilitated SF degradation (PEG-1 > PEG-0.5 > PEG-0 > PEG-2), and the mass loss of the scaffolds in PEG-1 was more than 30%, while in PEG-2 it was less than 20% after 8 days (P < 0.05). The addition of PEG strengthened the mechanical properties of the scaffold (PEG-1 > PEG-2 > PEG-0.5 > PEG-0), as the Young''s modulus increased from 41.72 ± 3.40 MPa for PEG-0 to 76.12 ± 3.73 MPa for PEG-1 (P < 0.05). PEG was favorable for the osteogenic differentiation of BMSCs (PEG-0.5 > PEG-1 > PEG-2 > PEG-0). The enhancements were attributable to the increased hydrophilicity and nHAP dispersion, as well as to the secondary structure transformation of SF. The PEG content was deemed to be optimal when the SF/nHAP/PEG ratio was equal to 10 : 2 : 1.

The modification of the mechanical and degradation properties of a SF scaffold combined with PEG and nHAP is demonstrated.     

Formation of vasculogenic mimicry in bone metastasis of prostate cancer: Correlation with cell apoptosis and senescence regulation pathways

Vasculogenic mimicry (VM) has been found in prostate cancer (PCa) as an independent marker of poor prognosis. To investigate the correlation between VM and bone metastasis in PCa, a total of 80 cases were analyzed by CD31 and PAS dual-staining as well as the follow-up data. All cases were divided into two groups: VM-positive and VM-negative (VM-pos/VM-neg). Immunohistochemical staining for investigating the expression of Casepase-3, Bcl-2/Bax, and SA-β-gal was performed. 28 of the 80 PCa cases exhibited VM structure (35.0%). The incidence of bone metastasis in the VM-pos and VM-neg was 67.9% (19/28) and 38.5% (20/52), respectively. The positive rate of Casepase-3 and Bcl-2 expression was significantly different of the two groups (Caspases-3: VM-pos 71.4%, 20/28 vs VM-neg 42.3%, 22/52; Bcl-2: VM-pos 35.7%, 10/28 vs VM-neg 65.4%, 34/52). Bcl-2/Bax ratio of the VM-pos (0.71 ± 0.22) was lower than that of the VM-pos (0.89 ± 0.13). In addition, a higher frequency of SA-β-gal was detected in VM-pos (64.29 ± 86.42) than in VM-neg (25.37 ± 72.21). Taken together, our findings demonstrate that PCa with VM has the tendency to develop bone metastasis. Activations of cell apoptosis and senescence regulation pathways may play important roles in the formation process of VM structure.     

珂立苏治疗足月新生儿呼吸窘迫综合征临床研究

目的 研究国产外源性肺表面活性物质（珂立苏）对足月新生儿呼吸窘迫综合征（respiratory distress syndrome,RDS）的疗效。方法 本研究分为两阶段：（1）第一阶段：2011年1月至2012年6月,研究珂立苏治疗足月儿RDS的疗效。根据家长意愿将RDS患儿分为珂立苏组（74例）和固尔苏组（80例）,比较在补充外源性肺表面活性物质后两组患儿血气变化、住院时间、住院费用、重要并发症发生率及重复用药率。（2）第二阶段：2012年7月至2013年3月,比较不同剂量珂立苏治疗足月儿RDS的疗效。将接受珂立苏治疗的80例足月RDS患儿,根据胸部X线改变分为轻中度组（X线胸片Ⅱ～Ⅲ级）50例和重度组（X线胸片Ⅳ级）30例,每组又分成小剂量（每次30 ～ 40 mg/kg）和大剂量（每次70 ～ 100 mg/kg）两个亚组,比较不同剂量珂立苏对RDS的疗效。结果 第1阶段：（1）两组RDS患儿在用药前及用药后0。5h和6h,动脉血pH、PaCO2和PaO2各指标差异无统计学意义（P＞0.05）。（2）两组患儿机械通气天数、总给氧天数、住院天数及重复用药率差异无统计学意义（P＞0.05）。（3）两组患儿多脏器功能衰竭、持续性肺动脉高压、急性肾功能衰竭、气胸发生率和病死率差异无统计学意义（P＞0.05）。（4）珂立苏与固尔苏组患儿平均住院费用分别为28。778千元及31.827千元,固尔苏组患儿平均减少9.6％（P＜0.05）。第2阶段：（1）对轻中度RDS,小剂量与大剂量珂立苏治疗前及治疗后0.5h和6h,pH、PaCO2和PaO2各指标差异无统计学意义（P＞0.05）。（2）对重度RDS,大剂量珂立苏改善动脉血气的效果优于小剂量珂立苏（P＜0.05）;小剂量组与大剂量组的重复用药率分别为20.0％（3/15）和33.3％ （5/15）,大剂量组患儿平均减少40％。结论 （1）对足月儿RDS,珂立苏与固尔苏均可显著改善患儿低氧血症和高碳酸血症,两组患儿机械通气时间、总吸氧时间及住院时间相似,但珂立苏组住院费用降低。（2）对轻中度RDS,小剂量与大剂量珂立苏具有相似的临床疗效;但对重度RDS,大剂量珂立苏的疗效维持较久,并可在一定程度上减少重复用药率。     

Clinical and radiological outcomes after treatment of sagittal fracture of mandibular condyle (SFMC) by using occlusal splint in children

This study was designed to investigate the effects of occlusal splints in the treatment of sagittal fractures of the mandibular condyle in children. From January 1995 to December 2011, 37 sagittal fractures of the mandibular condyle in 30 patients aged 4–8 years old were included in this study. All the patients were treated with 1–2 mm occlusal splints in the molar region. The mouths of the patients were kept slightly open by the occlusal splints for 3–6 months, and we reviewed the clinical and radiological remodelling of the affected condyles after treatment. Excellent (n = 20) and good (n = 10) clinical outcomes were achieved with full radiological remodelling seen in 19 and partial remodelling in 11. Treatment with occlusal splints is effective in delivering good results and function with minimal morbidity in children with sagittal fractures of the condyle, while permitting ongoing remodelling and growth in the short term.     

Angiopoietin-1 gene-modified human mesenchymal stem cells promote angiogenesis and reduce acute pancreatitis in rats

Mesenchymal stem cells (MSCs) can serve as a vehicle for gene therapy. Angiopoietin-1 (ANGPT1) plays an important role in the regulation of endothelial cell survival, vascular stabilization, and angiogenesis. We hypothesized that ANGPT1 gene-modified MSCs might be a potential therapeutic approach for severe acute pancreatitis (SAP) in rats. Human umbilical cord-derived MSCs with or without transfection with lentiviral vectors containing the ANGPT1 gene were delivered through the tail vein of rats 12 h after induction of SAP. Administration of MSCs alone significantly reduced pancreatic injury and inflammation, as reflected by reductions in pancreatitis severity scores and serum amylase and lipase levels as well as reducing the serum levels of proinflammatory cytokines (TNF-α, IFN-γ, IL-1β, and IL-6). Furthermore, administration of ANGPT1-transfected MSCs resulted in not only further reductions in pancreatic injury and serum levels of proinflammatory cytokines, but also promotion of pancreatic angiogenesis. These results suggest that MSCs and ANGPT1 have a synergistic role in the treatment of SAP. ANGPT1 gene-modified MSCs may be developed as a potential novel therapy strategy for the treatment of SAP.     

Fabrication of uniform urchin-like N-doped NiCo2O4@C hollow nanostructures for high performance supercapacitors

Transition metal oxides are commonly used in electrochemical energy storage materials, but there are still many drawbacks that impede a wide range of applications. Heteroatom doping can significantly improve its performance. Herein, we have successfully prepared highly uniform N-doped NiCo₂O₄@C hollow nanostructures for supercapacitors by a two-step hydrothermal treatment associated with successive annealing process. Prepared N-doped NiCo₂O₄@C materials exhibited an admirable specific capacitance of 1028 F g⁻¹ at a current density of 3 A g⁻¹, with 625 F g⁻¹ remaining even at high current density of 20 A g⁻¹. Besides, this composite showed good electrochemical stability with capacity retention of 84% after 5000 cycles repetitive galvanostatic charge–discharge test at 10 A g⁻¹. An asymmetric supercapacitor was assembled by the N-doped NiCo₂O₄@C electrode, attached activate carbon (AC) as a counter electrode, exhibiting a high energy density of 26.67 W h kg⁻¹ at a power density of 402 W kg⁻¹. The improvement of electrochemical performance is ascribed to the co-doping of nitrogen and carbon atoms. These results indicate that N-doped NiCo₂O₄@C can be employed as an ideal electrode material for electrochemical energy storage.

Procedure for fabricating N-doped NiCo₂O₄@C hollow nanostructures.     

Retracted Article: Long noncoding RNA ANRIL protects cardiomyocytes against hypoxia/reoxygenation injury by sponging miR-195-5p and upregulating Bcl-2

Long noncoding RNAs have been widely accepted to play important roles in acute myocardial infarction (AMI). The dysregulation of cyclin-dependent kinase inhibitor 2B antisense RNA 1 (ANRIL) was discovered in AMI patients. Nevertheless, the detailed role and molecular mechanisms of ANRIL in AMI remain indistinct. The levels of ANRIL, miR-195-5p and Bcl-2 mRNA were determined by qRT-PCR. western blot was performed to assess the expression of Bcl-2, Bax, Cyclin D1 and p21. Cell proliferation was detected by CCK-8 assay, and cell apoptosis was measured by flow cytometry. The targeted correlation between ANRIL and miR-195-5p was confirmed by the dual-luciferase reporter and RNA pull-down assays. Our data revealed that ANRIL was downregulated and miR-195-5p was upregulated in the serum of AMI patients and hypoxia/reoxygenation (H/R)-induced myocardial cells. ANRIL upregulation or miR-195-5p knockdown alleviated H/R-induced myocardial cell injury. Moreover, ANRIL sequestered miR-195-5p by acting as a sponge of miR-195-5p. ANRIL upregulated Bcl-2 expression by sponging miR-195-5p. Additionally, ANRIL overexpression alleviated H/R-induced myocardial cell injury by upregulating Bcl-2. In conclusion, our study indicated that ANRIL upregulation alleviated H/R-induced myocardial cell injury partially through sponging miR-195-5p and upregulating Bcl-2, highlighting its role as a promising mediator for new therapies for AMI treatment.

Long noncoding RNAs have been widely accepted to play important roles in acute myocardial infarction (AMI).     

下颌骨升支骨结核一例

颌骨结核作为肺外结核的少见病近年呈增多趋势,其发病形式、临床表现也有了较大的变化,容易被误诊为炎症或良恶性肿瘤。本文就近期收治的1例发生于下颌升支骨结核的临床表征、病理表现及相关实验室特点作一阐述,并通过文献复习,分析颌骨结核的临床特征,以期引起重视,提高对疾病的认识。     

术前睡眠质量对老年患者无痛结肠镜检查术中丙泊酚用量的影响*

目的评估术前睡眠质量对老年患者无痛结肠镜检查术中丙泊酚用量的影响。方法择期行无痛结肠镜检查术患者60例,年龄65～76岁,美国麻醉医师协会(ASA)分级Ⅱ～Ⅲ级。术前根据匹兹堡睡眠质量指数(PSQI)诊断有无睡眠障碍,其中,PSQI≥5分为睡眠障碍;PSQI 5分为睡眠正常。据PSQI评分将患者分为睡眠障碍组和睡眠正常组,每组30例。两组患者诱导前5 min均静脉注射羟考酮0.05 mg/kg。静脉注射丙泊酚负荷剂量0.50～1.00 mg/kg,待睫毛反射消失后麻醉维持:静脉泵注丙泊酚3～5 mg/(kg·h)。检查过程中发生体动反应时追加丙泊酚0.50 mg/kg。主要观察指标为操作过程中丙泊酚用量。次要观察指标:术中警觉与镇静评分(OAA/S评分);术中呼吸抑制、体动反应、腹痛和恶心呕吐等发生情况;诱导时间、苏醒时间、手术时间;血氧饱和度降低[脉搏血氧饱和度(Sp O2)分别小于95%和90%的发生情况]、检查结束至进入恢复室的时间。用疼痛视觉模拟评分(VAS)(0～10 cm)评价结肠镜检查后的疼痛和虚弱程度。记录两组患者术后胃肠功能指标。结果与睡眠障碍组比较,睡眠正常组患者操作过程中的丙泊酚用量明显减少(P 0.05)。两组患者Sp O2下降低于95%的例数和下降低于90%的例数均相近(P 0.05)。术中OAA/S评分、呼吸抑制、体动反应、腹痛和恶心呕吐等发生情况和检查结束至进入恢复室的时间及VAS评分结果在两组患者间差异无统计学意义(P 0.05)。与睡眠障碍组比较,睡眠正常组结肠镜检查后苏醒时间明显缩短(P 0.05),两组术后疼痛评分和虚弱程度均接近(P 0.05)。两组患者术后胃肠功能指标差异均无统计学意义(P 0.05)。结论术前睡眠障碍可明显增加老年患者无痛结肠镜检查术中的丙泊酚用量,并延缓患者麻醉苏醒。