Effects of angle and laminectomy on triangulated pedicle screws

We aimed to demonstrate the effect of angle and laminectomy on paired pedicle screws to determine whether a 90 degrees screw angle is optimal as has been previously suggested. According to the angle between right and left screws, 28 calf vertebrae were divided into three groups and instrumented as follows: Group I: 60 degrees screw angle; Group II: 90 degrees angle; Group III: 60 degrees angle with laminectomy. The screws were connected using rods and cross-fixators and tested to peak pullout force. Triangulated pedicle screws provided 76.5% more pullout strength than single screws. Most of the specimens failed through loss of convergence angle (toggling of screws on the rods) and subsequent uni- or bilateral screw pullout. Mean+/-SD peak loads were: Group I: 2071+/-622 N; Group II: 1753+/-497 N; Group III: 2186+/-587 N. The differences were not significant (p>0.05). 90 degrees triangulation was not associated with a superior pullout performance versus conventional 60 degrees triangulation, suggesting that achieving additional triangulation angle is not necessary to obtain increased pullout strength. Laminectomy did not alter the effect of triangulation on fixation strength.     

青年性腰椎弓根崩裂直接修复后TSRH钩钉系统固定12例初步报告

[目的]评价TSRH钩钉系统对青年患者腰椎弓崩裂直接修复后固定的临床疗效。[方法]自2001年7月~2003年10月,对12例男性单纯腰椎弓崩裂患者(16~31周岁)行腰椎弓崩裂自体骨直接修复峡部裂后TSRH椎板钩、椎弓根钉固定术。术后随访,根据术后X线、CT结果评价修复效果,并根据MacNab's标准进行临床评价。[结果]经过6~19个月随访,所有患者腰椎弓崩裂影像学全部融合;临床下腰痛显著缓解,按MacNab's标准,优8例,良3例,一般1例;无手术及内固定相关并发症发生。[结论]直接修复后TSRH钩钉系统固定治疗青年性腰椎弓崩裂能充分保留腰椎运动节段,在减少融合节段的同时能有效恢复腰椎稳定,操作简便、安全,固定可靠,是一种合乎逻辑的治疗青年性腰椎弓崩裂方法。     

The effect of single and repeated UVB radiation on rabbit cornea

Background Cumulative effect of ultraviolet radiation (UVR) is an important aspect of UV corneal damage. The purpose of this study was to apply high resolution magic angle spinning proton nuclear magnetic resonance (HR-MAS ¹H NMR) spectroscopy to evaluate the effect of single and repeated UV radiation exposure of the same overall dose on the rabbit cornea.Methods Corneal surfaces of 24 normal rabbit eyes were examined for the effects of UVB exposure (312 nm). In the first group (UVB1), animals were irradiated with a single dose (3.12 J/cm²; 21 min) of UVB radiation. The animals in the second group (UVB2) were irradiated three times for 7 min every other day (dose of 1.04 J/cm²; days 1, 3, 5) to give the same overall dose (3.12 J/cm²). The third group served as an untreated control group. One day after the last irradiation, the animals were sacrificed, and the corneas were removed and frozen. HR-MAS ¹H NMR spectra from intact corneas were obtained. Special grouping patterns among the tissue samples and the relative percentage changes in particular metabolite concentrations were evaluated using modern statistical methods (multivariate analysis, one-way ANOVA).Results The metabolic profile of both groups of UVB-irradiated samples was significantly different from the control corneas. Substantial decreases in taurine, hypo-taurine and choline-derivatives concentrations and substantial elevation in glucose and betaine levels were observed following the UVR exposure. There was no significant difference between the effect of a single and repeated UVB irradiation of the same overall dose.Conclusions For the first time, the effects of single and repeated UVR doses on the metabolic profile of the rabbit cornea were analysed and compared. The combination of HR-MAS ¹H NMR spectroscopy and modern statistical methods (multivariate analysis, one-way ANOVA) proved suitable to assess the overall view of the metabolic alterations in the rabbit corneal tissue following UVB radiation exposure.     

ApoE-/-小鼠肾动脉粥样硬化斑块破裂的肾损害

目的 探讨ApoE^-/-小鼠肾动脉粥样硬化斑块破裂对下游肾脏的损伤机制。 方法 采用ApoE^-/-小鼠建立粥样硬化性肾动脉狭窄(ARAS)动物模型。选择肾动脉狭窄程度 <50％的ApoE^-/-小鼠，按斑块分为破裂组和未破裂组；选择同条件喂养的C57BL/6J 野生型小鼠为对照组。常规检测Scr及尿 N-乙酰-β-氨基葡萄糖苷酶(NAG)活性；Western印迹检测细胞核中核转录因子κBp65（NF-κBp65）、细胞间黏附分子1（ICAM-1）及P-选择素（P-sel）表达； RT-PCR检测白细胞介素6 （IL-6）mRNA表达；免疫组化染色检测巨噬细胞浸润情况。 结果破裂组Scr和尿NAG活性明显升高（均P < 0.01）；肾组织出现病理改变，肾间质中巨噬细胞浸润增加（P < 0.05）；细胞核中NF-κBp65表达增加（P < 0.05）；ICAM-1、P-sel、IL-6 mRNA表达增加（P < 0.05）。未破裂组上述指标与对照组比较，差异无统计学意义（P > 0.05）；肾脏未见明显病理改变。 结论 肾动脉粥样硬化斑块破裂可引起肾脏病理改变和肾功能受损；在粥样硬化性肾动脉狭窄的肾损害机制中，炎性反应是重要因素之一。     

吡咯烷二硫氨基甲酸酯对大鼠重症急性胰腺炎的影响

目的　探讨核转录因子 (NF κB)抑制剂吡咯烷二硫氨基甲酸酯 (PDTC)对大鼠重症急性胰腺炎 (SAP)的影响。方法　将 3 6只Wistar大鼠随机分组 :假手术组 (n =6) ,假手术 静脉注射组 (n =6) ,SAP组 (n =12 )和试验组 (n =12 )。各组于造模 6h后 ,测定血清淀粉酶及脂肪酶含量 ,取胰腺组织进行病理学评分 ,采用免疫组织化学法检测NF κB激活水平及胰腺细胞凋亡情况。结果　SAP组和试验组的胰腺细胞内NF κB呈激活状态 ,存在胰腺细胞凋亡 ,与前两组差异有显著性 (P <0 .0 1) ,试验组大鼠的胰腺组织病理学评分、血清淀粉酶及脂肪酶含量、NF κB激活及细胞凋亡水平与SAP组差异存在显著性 (P <0 .0 5 )。结论　在SAP发病机制中 ,NF κB是多种炎症介质的始动因子 ,PDTC可以有效抑制胰腺细胞中NF κB的激活 ,促进胰腺细胞凋亡 ,减少胰酶释放 ,减轻胰腺组织的病理损害。     

The estimation of mean nuclear volume in the diagnosis of breast carcinoma.

Sixty-two cases of breast pathology were randomly selected from the files of the Dunedin Public Hospital for evaluation of mean epithelial nuclear volume. The cases were comprised of both benign and malignant ductal epithelial disease, diagnosed in cytological smears or in histological sections. Nuclear volume in histological preparations was estimated by the stereological technique of point-line intercept measurements to derive volume-weighted mean volumes (vV). An index of the nuclear volume (Vi) of cytology smears was calculated from measurements of nuclear areas by either image analysis Vi(e) or point-line intercepts Vi(p). By all methods of analysis a clear distinction of nuclear volume was found between the benign [means for the cytology were 148 microns 3 (Vi(e)) or 246 microns 3 (Vi(p)), and 203 microns 3 (Vv) for the histology specimens] and malignant diseased cases [means for cytology: 524 microns 3 (Vi(e)) or 886 microns 3 (Vi(p)), and 587 microns 3 (vV) for the histology specimens].     

Operative treatment of intertrochanteric hip fractures: an overview of modern advances and techniques

Hip fractures have been one of the most studied injury pattern in adults. The number of hip fractures is increasing exponentially; furthermore, the cost of treatment places great economic strain on society. There have been recent developments in hip-fracture treatment, particularly involving the intertrochanteric region, with emphasis on deformity prevention to try to optimize patient functional outcomes. In this article, we outline some of these developments with an emphasis on changes in implant design.     

Nuclear bridges in multinucleated giant cells associated with primary lymphoma of the brain in acquired immune deficiency syndrome (AIDS)

Summary In an autopsied case of a 37-year-old man with acquired immune deficiency syndrome (AIDS), multinucleated giant cell encephalopathy was noted in close proximity to multiple nodules of primary lymphoma of the brain. Some multinucleated giant cells and macrophages contained HTLV-III-like viral particles. Nuclear bridges, thin strands connecting individual nuclei with one another, were observed with both light and electron microscopes within some of the multinucleated giant cells. There were also thin tapering nuclear processes, which were probably part of nuclear bridges. The possibility that the nuclear bridges and processes represent amitotic nuclear division is discussed.     

骨桥栓桩与界面螺钉固定前交叉韧带重建移植物胫骨端的临床价值对比

对比骨桥栓桩与界面螺钉在膝关节前交叉韧带断裂重建术中的临床价值。方法 回顾性分析2019年7月—2020年12月我院700例在关节镜下行前交叉韧带重建手术的患者,股骨隧道均以横穿钉固定。按移植物胫骨端固定方式分为骨桥栓桩组（380例）及界面螺钉组（320例）。对比两组手术时间、切口长度、住院时间及费用;比较两组术后3个月、12个月胫骨隧道大小、膝关节功能Lyshlom评分及术后12个月关节松弛度。结果 两组患者手术时间、胫骨端切口长度、住院时间比较差异均无统计学意义（P＞0.05）,但骨桥栓桩组手术费用显著低于界面螺钉组（P＜0.05）。术后3个月、12个月两组患者胫骨隧道大小、膝关节功能Lyshlom评分及关节松弛度比较差异均无统计学意义（P＞0.05）,但随着时间的延长,两组患者隧道均有不同程度的扩大（P＜0.05）。结论 对于行关节镜下前交叉韧带重建术的患者,采用骨桥栓桩胫骨端固定方式可取得与界面螺钉固定相当的临床效果,但骨桥栓桩固定更具医疗经济优势,是一种可广泛推广的胫骨端固定方法