Powder Compression Properties of Paracetamol,Paracetamol Hydrochloride,and Paracetamol Cocrystals and Coformers

The objective was to study the relationship between crystal structure, particle deformation properties, and tablet-forming ability for the monoclinic form of paracetamol (PRA), 2 cocrystals and a salt crystal of PRA in addition to 2 coformers (oxalic acid and 4,4′-bipyridine). Thus, the structure–property–performance relationship was investigated. Analytical powder compression was used for determination of effective plasticity, as inferred from the Heckel yield pressure and the Frenning parameter, and the elastic deformation was determined from in-die tablet elastic recovery. The plasticity could not be linked to the crystal lattice structure as crystals containing zig-zag layers displayed similar plasticity as crystals containing slip planes. In addition, crystals containing slip planes displayed both high and low plasticity. The mechanical properties could not be linked to the tablet-forming ability as the tablet tensile strength, unexpectedly, displayed a tendency to reduce with increased plasticity. Furthermore, the elastic deformation could not explain the tablet-forming ability. It was concluded that no relationship between structure–property–performance for PRA and its cocrystals and salt could be established. Thus, it was indicated that to establish such a relationship, an improved knowledge of crystallographic structure and interparticle bonding during compaction is needed.     

Comparison of image compression viability for lossy and lossless JPEG and Wavelet data reduction in coronary angiography

Background: Lossless or lossy compression of coronary angiogram data can reduce the enormous amounts of data generated by coronary angiographic imaging. The recent International Study of Angiographic Data Compression (ISAC) assessed the clinical viability of lossy Joint Photographic Expert Group (JPEG) compression but was unable to resolve two related questions: (A) the performance of lossless modes of compression in coronary angiography and (B) the performance of newer lossy wavelet algorithms. This present study seeks to supply some of this information. Methods: The performance of several lossless image compression methods was measured in the same set of images as used in the ISAC study. For the assessment of the relative image quality of lossy JPEG and wavelet compression, the observers ranked the perceived image quality of computer-generated coronary angiograms compressed with wavelet compression relative to the same images with JPEG compression. This ranking allowed the matching of compression ratios for wavelet compression with the clinically viable compression ratios for the JPEG method as obtained in the ISAC study. Results: The best lossless compression scheme (LOCO-I) offered a mean compression ratio (CR) of 3.80:1. The quality of images compressed with the lossy wavelet-based method at CR = 10:1 and 20:1 was comparable to JPEG compression at CR = 6:1 and 10:1, respectively. Conclusion: The study has shown that lossless compression can exceed the CR of 2:1 usually quoted. For lossy compression, the range of clinically viable compression ratios can probably be extended by 50 to 100% when applying wavelet compression algorithms as compared to JPEG compression. These results can motivate a larger clinical study.     

Ulnar nerve lesion at the wrist related to pisotriquetral joint arthropathy

Introduction: Ulnar nerve lesions at the wrist (UNLW) are always difficult to localize clinically and sometimes electrophysiologically. Finding conduction block when studying ulnar motor nerve conduction (CB) across the wrist is sometimes the only way to demonstrate that the ulnar deep motor branch (UDMB) is entrapped. Methods: An elderly woman who had bilateral carpal tunnel syndrome (CTS) and thumb osteoarthritis for many years experienced worsening of left hand impairment recently. Results: Electrodiagnostic and ultrasound examinations revealed an acute and severe UDMB lesion related to pisotriquetral joint effusion. The patient received a local injection of a corticosteroid that provided rapid recovery. Conclusions: The diagnosis of UDMB lesion is especially difficult when CTS coexists, but CTS may allow for early diagnosis, if CB at the wrist is not overlooked. Chondrocalcinosis was responsible for the systemic inflammation, the CTS, the pisotriquetral joint effusion, and the UDBM compression, which has not been reported previously. Muscle Nerve, 2013     

经皮椎体成形术在椎体压缩骨折及椎体肿瘤治疗中的临床应用

目的 总结分析经皮椎体成形术(PVP)在骨质疏松性椎体压缩骨折及椎体肿瘤治疗中临床应用的疗效.方法 宣武医院神经外科2007年1月至2012年6月应用PVP治疗45例患者共62个病变椎体,随访时间点为术后24h、3、6、12、24及36个月,采用VAS、ODI评价其临床疗效,椎体前缘高度及Cobb角评估影像学结果.结果 平均随访时间(13.9±7.8)个月,术后24 h,患者VAS疼痛评分、ODI指数及Cobb角分别由术前(7.3±1.9)分、32.0±3.4和15.0°±2.3°降至术后(4.8±1.6)分、22.1±2.1和14.0°±1.9°(P＜0.05),椎体前缘高度由术前(16.0±1.8) mm升至(19.0±2.1)mm(P＜0.05).3～36个月随访期内,VAS评分、椎体前缘高度及Cobb角差异无统计学意义(P＞0.05).随访中约54％患者VAS评分维持在5分以内.结论 PVP是治疗骨折及肿瘤所致的椎体源性疼痛简单有效的微创疗法,临床疗效稳定.     

Therapeutic value of 21-aminosteroid U74389F in acute spinal cord injury

Abstract

The effect of bolus injections of 21-aminosteroid U74389F after an acute spinal cord compression trauma in rats was studied. Cortical somatosensory evoked potentials (CSEPs) were recorded before and after a weight-induced injury of 120 g and monitored up to five hours post-injury. All U74389F treatments were given as i.v. bolus injections of 15, 7.5, and 3.75 mg kg^–1 at 1, 2, 3 h after the trauma, respectively. The CSEPs were abolished immediately after the injury in the control and treated animals. The majority of the treated animals (88.8%) demonstrated a return of the CSEPs within the second hour post-injury. In contrast, the animals in the control group showed only 44.4% recovery at this time period. At three hours post-injury, U74389F-treated animals (n = 18) showed a full recovery (100%) while the recovery rate remained at 44.4% for the control animals. We conclude that the bolus administration of U74389F one hour after injury facilitates the return of the spinal cord function as measured by the CSEPs in this compression model of acute spinal cord trauma. [Neurol Res 1993; 15: 321-326]     

微板速率法检测丙氨酸氨基转移酶的研究

目的探讨全自动酶联免疫分析系统微板速率法检测丙氨酸氨基转移酶(ALT)的方法评价和临床应用。方法参照国际临床化学联合会(IFCC)的推荐方法,结合分析系统建立微板速率法,通过方法学试验,评价其线性、批内和批间重复性;比较823例体检者血清标本采用微板速率法与常规生化分析仪法检测ALT的结果,并评价方法的临床应用。结果微板速率法检测ALT,在活性303U/L以下具有良好的线性;批内和批间变异系数均小于1/5TEa,其检测结果与常规生化分析仪的相关性良好。结论全自动酶联免疫分析系统微板速率法检测ALT,为大批量标本同时检测ALT和ELISA项目提供了很好的选择,值得临床推广使用。     

COPD病人急性期雾化吸入β2激动剂和激素的观察及护理

对80例COPD急性期住院病人,采用压缩雾化机加入博利康尼2.5 mg 地塞米松5 mg 生理盐水3mL,经呼吸道雾化吸入治疗7 d.结果77例效果满意(96.3%),病人喘息、呼吸困难明显减轻,肺部听诊干鸣、湿啰音明显减少,SpO2上升至97%～99%,提示COPD急性期住院病人使用压缩雾化吸入β2激动剂和激素能取得显著的治疗效果.     

AO跟骨钢板治疗Sanders III、IV型跟骨骨折18例观察

目的探讨AO跟骨钢板治疗SandersIII、IV型跟骨骨折的疗效。方法自2001年2月至2005年6月,对18例23足SandersIII、IV型跟骨骨折,采用AO跟骨钢板加自体髂骨植骨进行复位内固定治疗。结果本组病例随访6~36个月,平均随访时间18.5个月。按Maryland足部评分标准评价,优8足,良11足,中3足,差2足,优良率78.2%。结论本方法治疗SandersIII、IV型跟骨骨折复位满意,固定牢靠,术中自体髂骨植骨,术后早期关节功能锻炼,疗效肯定,是一种目前治疗SandersIII、IV型跟骨骨折的较好方法。     

Fixed-angle plate osteosynthesis of the patella – An alternative to tension wiring?

Background

The goal of this study is carry out a biomechanical evaluation of the stability of a bilateral, polyaxial, fixed-angle 2.7 mm plate system specifically designed for use on the patella. The results of this approach are then compared to the two currently most commonly used surgical techniques for patella fractures: modified anterior tension wiring with K-wires and cannulated lag screws with anterior tension wiring.

Methods

A transient biomechanical analysis determining material failure points of all osteosyntheses were conducted on 21 identical left polyurethane foam patellae, which were osteotomized horizontally. Evaluated were load (N), displacement (mm) and run-time (s) as well as elastic modulus (MPa), tensile strength (MPa) and strain at failure (%).

Findings

With a maximum load capacity of 2396 (SD 492) N, the fixed-angle plate proved to be significantly stronger than the cannulated lag screws with anterior tension wiring (1015 (SD 246) N) and the modified anterior tension wiring (625 (SD 84.9) N). The fixed-angle plate displayed significantly greater stiffness and lower fracture gap dehiscence than the other osteosyntheses. Additionally, osteosynthesis deformation was found to be lower for the fixed-angle plate.

Interpretation

A bilateral fixed-angle plate was the most rigid and stable osteosynthesis for horizontal patella fractures with the least amount of fracture gap dehiscence. Further biomechanical trials performed under cycling loading with fresh cadaver specimen should be done to figure out if a fixed-angle plate may be an alternative in the surgical treatment of patella fractures.