Postoperative annular pseudocyst: report of two cases with an unusual complication after microdiscectomy, and successful treatment by percutaneous aspiration and steroid injection

BACKGROUND CONTEXT: After microdiscectomy for extruded disc fragments, patients may develop recurrent symptoms from numerous causes. Postoperative annular pseudocysts represent a unique entity not previously described in the medical literature. PURPOSE: To report unique imaging findings in two patients who presented with recurrent radiculopathic symptoms after microdiscectomy. To report successful percutaneous aspiration and steroid injection in one of these cases. STUDY DESIGN/SETTING: Report of two cases. METHODS: Two patients underwent preoperative imaging with noncontrast magnetic resonance imaging (MRI) and postoperative imaging with pre- and postcontrast MRI. One of these patients underwent therapeutic computed tomography (CT)-guided aspiration and injection. RESULTS: MRI demonstrated T2 hyperintense and enhancing collections, which conformed to the shape of the resected disc fragment and communicated with the disc annulus. One of these cases demonstrated enlargement over several months with worsening of symptoms. Aspiration of the lesion produced thick fluid. The patient experienced marked relief of symptoms after the aspiration and injection of steroid into the lesion. CONCLUSIONS: The unique imaging findings in these patients represent a previously undescribed complication of microdiscectomy, which we have termed "postoperative annular pseudocyst." We have successfully treated one case with CT-guided percutaneous aspiration and injection.     

Disseminated bacille Calmette�CGu��rin disease in HIV-infected South African infants

Objective

To determine the population-based incidence of disseminated bacille Calmette–Guérin (BCG) disease in HIV-infected infants (aged ≤ 1 year) in a setting with a high burden of tuberculosis and HIV infection coupled with a well-functioning programme for the prevention of HIV infection in infants.

Methods

The numerator, or number of new cases of disseminated BCG disease, was derived from multicentre surveillance data collected prospectively on infants with a confirmed HIV infection during 2004–2006. The denominator, or total number of HIV-infected infants who were BCG-vaccinated, was derived from population-based estimates of the number of live infants and from reported maternal HIV infection prevalence, vertical HIV transmission rates and BCG vaccination rates.

Findings

The estimated incidences of disseminated BCG disease per 100 000 BCG-vaccinated, HIV-infected infants were as follows: 778 (95% confidence interval, CI: 361–1319) in 2004 (vertical HIV transmission rate: 10.4%); 1300 (95% CI: 587–2290) in 2005 (transmission rate: 6.1%); and 1013 (95% CI: 377–1895) in 2006 (transmission rate: 5.4%). The pooled incidence over the study period was 992 (95% CI: 567–1495) per 100 000.

Conclusion

Multicentre surveillance data showed that the risk of disseminated BCG disease in HIV-infected infants is considerably higher than previously estimated, although likely to be under-estimated. There is an urgent need for data on the risk–benefit ratio of BCG vaccination in HIV-infected infants to inform decision-making in settings where HIV infection and tuberculosis burdens are high. Safe and effective tuberculosis prevention strategies are needed for HIV-infected infants.     

Molecular basis for the lack of T cell proliferation induced by an altered peptide ligand

In this report, we explore the mechanisms underlying cell cycle progression in T cells stimulated with an altered peptide ligand (APL) versus wild-type peptide. APL stimulation did not induce proliferation compared to wild-type peptide stimulation. To determine the point at which cell cycle progression is blocked, we have examined molecules responsible for regulating the retinoblastoma tumor suppressor gene product, pRb, which in its active state prevents G1/S progression. The majority of cells stimulated with an APL did not progress beyond G1; however, a small population did make the G1/S transition. These few cells passed the late G1 restriction point, divided and subsequently arrested at the next G1 phase. The lack of sustained signaling events following stimulation with an APL failed to induce cyclin E:cdk2 activity, a regulator which hyper-phosphorylates and inactivates pRb. Exogenous IL-2 addition did not compensate for the lack of proliferation following APL stimulation. Furthermore, the inability of the cells to enter S phase during partial T cell activation cannot be accounted for by p27Kip1 inhibition of cyclin E:cdk2 complexes. Upon APL stimulation, an increase in association of p27Kip1 with cyclin E:cdk2 complex was not observed, suggesting that instead, decreased cyclin E:cdk complex formation might contribute to the failure to progress from G1/S. Therefore, while for a majority of cells, wild-type stimulation results in cell cycle progression, APL stimulation is not sufficient to drive cells beyond G1.      

硝普钠的光解分析法及其在透皮吸收研究中的应用

依据已报告的光解分析法原理,建立了定量分析硝普钠的方法。在光源照射下,硝普钠溶液在394nm处吸收度增加属非线性动力学,但对一定浓度溶液,吸收度增量对浓度呈直线关系;无论光照30min或60min,依据△A₃₉₄都能准确地定量。本文方法线性范围50～1000mg/L,日内变异系数<1.9%;日间变异系数<2.6%,回收率99.0～100.1%。共存的少量血清蛋白、十八醇、维生素B₁₂、丙二醇、氮酮以及间硝苯啶、尼群地平、维拉帕米等均不干扰测定。方法已成功地用于透皮吸收剂的研究。     

移植肾急性排斥反应的SonoVue超声造影成像特征

目的:观测移植肾排斥反应的SonoVue超声造影特征,为建立移植肾排斥反应的SonoVue超声造影诊断标准提供依据。方法:选择2006-01/12就诊于上海交通大学附属第一人民医院超声科的同种异体移植肾患者25例,均知情同意。其中随访确诊移植肾功能正常患者20例,移植术后时间4～90个月;穿刺活检病理证实发生急性排斥反应5例,急性排斥的发生时间10～70d。选用仪器为SIEMENS公司Sequoia512和ESAOTES.P.A公司MYLAB30彩色多普勒超声诊断仪,分别配备对比脉冲序列和造影匹配成像技术造影成像软件;造影剂为SonoVue,剂量选择为0.6￣1.5mL;常规超声检查结束后进行超声造影,实时存储图像,回放分析。分析移植肾动脉主干、段动脉、叶间动脉、弓形动脉及肾实质微循环灌注情况,主要包括开始增强时间、回声强度及分布均匀度。结果:25例同种异体移植肾患者均成功进行超声造影,图像效果满意,图像数据均进入结果分析。①功能正常移植肾造影成像显示,造影剂依次通过肾动脉主干、段动脉、叶间动脉、弓形动脉、小叶间动脉;随后肾皮质、肾髓质分别开始显影;最后,整个移植肾实质呈造影剂强回声充填,分布均匀对称,肾脏切面形如“火球”。②移植肾发生急性排斥反应时,肾实质内造影剂充填始终较功能正常移植肾稀疏,包膜下皮质未能完全呈强回声充填,髓质内见散在的、大小不等、边界不清的低回声区,整个移植肾切面始终未能显示“火球”图像。结论:利用SonoVue进行移植肾的超声造影成像,可以显示急性排斥反应时血流灌注的特征性改变。     

去细胞同种心脏瓣膜的再内皮细胞化

目的:初步构建受体内皮细胞化的组织工程同种心脏瓣膜,减轻移植后免疫排斥反应,并探讨内皮细胞适宜的种植方法,增强内皮细胞与细胞外基质的黏附性。方法:实验于2004-06在阜外医院心血管外科先心病研究室完成。①实验材料:取冠状动脉搭桥患者术中剩余的大隐静脉(该材料是术中多余弃掉部分,患者知情同意),研究方案获伦理委员会批准。②实验方法:采用低渗液-去污剂(10g/L去氧胆酸)-核酸酶法去除同种心脏瓣膜组织中的全部细胞成分,构建去细胞的同种心脏瓣膜;取培养3～4代的成人大隐静脉内皮细胞,依照内皮细胞密度分为生理密度种植组:以1.5×108L-1密度种植;超生理密度种植组:以(4～5)×108L-1密度种植;生理密度反复种植组:以1.5×108L-1密度,反复种植3d。③实验评估:种植于脱去全部细胞的同种心脏瓣膜上,静态培养5d,扫描电镜观察内皮细胞的覆盖情况。结果:去细胞同种心脏瓣膜的细胞外基质有着良好的细胞黏附性;3种不同的内皮细胞种植密度,其中以内皮细胞超密度(4～5)×108L-1种植,静态培养5d,同种组织瓣膜表面基本覆盖单层内皮细胞,细胞间相互延伸汇合,形态结构良好。以生理密度种植内皮细胞覆盖率较低,细胞大多孤立存在,细胞间较少相互延伸汇合。生理密度反复种植3d,内皮细胞覆盖率低于超生理密度种植组,细胞间可见相互延伸汇合,细胞形态结构良好。结论:去细胞同种心脏瓣膜的再内皮细胞化保留了同种心脏瓣膜的正常结构、功能及良好的组织相容性,有望延长瓣膜的使用寿命,取得更好的临床疗效。     

持续气道内正压对阻塞性睡眠呼吸暂停低通气综合征患者动脉硬化早期表现的影响

背景和目的：阻塞性睡眠呼吸暂停低通气综合征（OSAHS）与心血管不良事件相关，其中包括心肌梗死和卒中。动脉硬化是导致这些心血管事件的主要机制。最近的横断面研究结果显示，没有合并症的OSAHS患者也存在动脉硬化的早期表现。因此，本研究观察了持续气道内正压（CPAP）治疗对动脉硬化的影响。为了验证OSAHS直接参与动脉硬化的假说，本研究只纳入没有合并症的重度OSAHS患者。方法：在为期2年的时间内对400例男性重度OSAHS患者进行了筛选，其中376例因合并高血压、