Schwann cell invasion of the conus medullaris: case report

As Schwann cells possess regenerative capabilities there is intense interest concerning their role in central nervous system (CNS) regeneration. We report on a case of an intramedullary schwannoma involving the conus medullaris and spinal cord above it. We discuss the possible origin of these cells and the mechanisms by which these cells may invade the CNS. We offer imaging and discuss experimental studies to support our hypothesis. This case concerns a 48-year-old man, who presented with a 6-month history of bilateral lower extremity weakness. Magnetic resonance imaging (MRI) revealed an intramedullary tumour extending from the conus to T11. At operation, following laminectomy and durotomy, a schwannoma was dissected free from the conus. Total gross resection of tumour was achieved. The patient made an uneventful and full recovery. This case shows that Schwann cells can invade the CNS. Manipulation of the transitional zone astrocytic barrier may offer a potential avenue for Schwann cells to enter the CNS in pathological states.     

腰椎间盘局限性高信号区(HIZ)的发生与分布规律

[目的]探讨腰椎间盘局限性高信号区（HIZ）的发生与分布规律。[方法]回顾性分析1000例腰椎MRI资料。对HIZ进行立体定位并分析其发生与分布规律。采用SPSS 11．0对所得数据进行统计学分析。[结果]本组HIZ发生率46．7％（前缘21．5％，后缘31．7％），共650个。其中，左侧238个（36．7％），右侧220个（33．8％），无明显侧别差异（x^2=1．0922，P〉0．05）。下缘446个（68．6％），明显多于中部及上缘。HIZ好发节段为L3.4～L5S1，可单发或多节段同时发生。其中，前缘HIZ多见于L2.3和L3.4椎间盘，后缘HIZ好发于L4.5和L5S1水平。[结论]腰椎间盘HIZ发生率较高。常见于椎间盘后缘、下缘和下腰椎。可单节段发生，亦可同时发生于多个节段。     

良性前列腺增生患者前列腺体积和移行区体积随年龄变化的调查

目的:调查良性前列腺增生(BPH)患者各年龄段前列腺总体积(TPV)、前列腺移行区体积(TZV),计算TZV与TPV的比值即移行区指数(TZI)的数值。分析年龄与上述指标的相关性。方法:经直肠B超测量1 563例BPH患者前列腺和前列腺移行区最大左右径、前后径和上下径,根据公式分别计算出TPV、TZV以及TZI。分析年龄与前列腺体积各参数的相关性。结果:BPH患者各年龄组TPV、TZV和TZI值分别为:50~59岁年龄组TPV(32.27±15.76)ml、TZV(9.55±7.98)ml、TZI 0.28±0.13;60~69岁年龄组TPV(40.93±17.45)ml、TZV(14.94±11.83)ml、TZI 0.34±0.16;70~79岁年龄组TPV(46.56±20.31)ml、TZV(19.54±19.25)ml、TZI 0.39±0.16;80~89岁年龄组TPV(47.85±26.63)ml、TZV(20.40±16.78)ml、TZI 0.41±0.19。BPH患者的TPV、TZV与年龄成显著正相关性(r1=0.232,r2=0.256,P均<0.01),TZV与年龄的相关系数要高于TPV与年龄的相关系数。结论:BPH患者的TPV、TZV值随着年龄的增长而增加,但是TZV增长的幅度要高于TPV增长的幅度,前列腺增生以移行区增生最为显著,并且我国BPH患者的移行区指数与其他人种之间可能存在不同。     

Cell membrane and mitotic markers show that the neonatal rat gubernaculum grows in a similar way to an embryonic limb bud

Aim/Background

How the gubernaculum guides the testis into the scrotum remains controversial, with various proposals from passive inversion to active growth. We aimed to determine if the gubernaculum contains an area of active proliferation, such as a “progress zone” in a growing embryonic limb bud, using a fluorescent cell membrane marker, 1,1′-didodecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate [DiIC₁₂(3)], to trace cell migration, and 5-bromodeoxyuridine (BUDR) (a thymidine analogue) as a mitotic marker.

Methods

Gubernacula were collected from neonatal male rats (n = 42, day 1-2, Sprague-Dawley) and cultured with calcitonin gene-related peptide (CGRP; 714 nmol/L). 1,1′-didodecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate-coated glass beads (diameter, 150-212 μm) were placed next to the bulb for the first 3 hours. Gubernacula were cultured for 3, 18, and 24 hours, then frozen sections cut and examined by confocal microscopy (wavelength, 549 nm). In a second experiment, pups not exposed to exogenous CGRP (n = 53, day 0, Sprague-Dawley) were injected intraperitoneally with BUDR (50 mg/kg of body weight); gubernacula were collected at 2, 48, 72, and 96 hours postinjection (PI), sectioned, and stained using immunohistochemistry to count the number of BUDR-positive cells per 100 cells (labeling index) in the bulb, cremaster, cord, and epididymis.

Results

After 24 hours' culture with CGRP, the bulb showed an oval region (diameter, 300 μm) of high fluorescence, and the cremaster region showed elongated cells migrating out of the bulb. When cultured without CGRP, the same oval region contained no fluorescence. In vivo BUDR labeling index increased in all areas until 48 hours postinjection and then decreased most rapidly in the bulb (P < .05), in the presence of endogenous CGRP from the genitofemoral nerve.

Conclusions

The rat gubernaculum contains a putative progress zone, such as in a growing limb bud, in the presence of CGRP. Cells migrate out of this zone to form cremaster muscle. We hypothesize that proliferation in the bulb elongates the gubernaculum, whereas proliferation of cremaster cells would increase gubernacular diameter. This brings to “life” the gubernaculum as an actively growing organ in contrast to the inert ligament connecting the testis to the scrotum portrayed in most anatomy textbooks.     

超声引导下犬肝注射醋酸高渗氯化钠混合液对射频消融毁损体积的影响

目的探讨超声引导下活体犬肝注射不同剂量的醋酸高渗氯化钠液(acetic acid hypertonic saline solution,AHS)后行射频消融(RFA),观察犬肝一次性毁损体积的变化。方法使用LDRF-120S多极RFA系统联合AHS对活体犬肝行RFA。健康成年杂种犬30只,随机分为5组(n=6)。A组:注射2ml AHS后立即行RFA;B组:注射2ml AHS后延时5min行RFA;C组:注射4ml AHS后立即行RFA;D组:注射4ml AHS后延时5min行RFA;E组:注射6ml AHS后立即行RFA。结果5组间平均起始阻抗差异无统计学意义(P>0.05);5组间平均消融时间差异有统计学意义(F=83.831,P<0.001),LSD-t检验分析各组间两两比较差异有统计学意义(P<0.001),在观察范围内E组平均消融时间最长;5组间平均毁损直径差异有统计学意义(F=53.488,P<0.001),在观察范围内E组平均毁损直径最大,LSD-t检验分析除D与E组间差异无统计学意义(P>0.05)外,其余各组间两两比较差异有统计学意义(P<0.001);网状纤维染色显示凝固坏死区及其邻近的正常肝组织均可见血管内血栓形成;E组在AHS注射过程中出现不同程度的外溢;A、B、C及D组14d内无动物死亡,E组死亡4只。结论活体犬肝局部注射AHS4ml后延时5min行RFA即可达到较理想的毁损体积。     

Correlation between the total volume,transitional zone volume of the prostate,transitional prostate zone index and lower urinary tract symptoms (LUTS)

Objectives Currently available studies show controversial data between the symptoms of the lower urinary tract and the volume of the prostate gland. The objective of the present study is to evaluate the relationship between the score of the lower urinary tract symptoms assessed according to the International Prostate Symptoms Score (IPSS) and the total (TV) and transitional (TZV) zone volume of the prostate and transitional prostate zone index (TZI). Materials and methods From 223 men with a mean age of 59.3 years (varying from 50 to 75), the scores of lower urinary tract symptoms, measured by the IPSS and TV and TZV, determined by transrectal ultrasonographies, were obtained. Furthermore, the TZI was determined in all cases by the TZV to TV rate of the prostate. The relationship between TV, TZV, and TZI and the data obtained using the symptoms score was statistically determined. Results The TV of the prostate were 25.5 ± 10.3, 25.0 ± 9.3, and 28.9 ± 13.5 g in individuals with mild, moderate, and severe symptoms, respectively (P = 0.15). Similarly, there was no significant difference when the TZV (7.6 ± 6.3, 7.6 ± 5.8, and 9.6 ± 6.8 g, respectively; P = 0.22) and the TZI (0.26 ± 0.1, 0.27 ± 0.1, and 0.30 ± 0.1, respectively; P = 0.33) were compared in the groups of men with mild, moderate, and severe symptoms of urinary difficulty. However, the quality of life (QoL) scores presented progressively worse values (1.7 ± 1.3, 3.1 ± 1.4, and 4.4 ± 1.2) as the severity of the lower urinary tract symptoms became worse (P < 0.001). The Pearson correlation coefficient between the TV (r = 0.15; P = 0.02), TZV (r = 0.16; P = 0.02), and the TZI (r = 0.14; P = 0.03) with the prostate symptom scores showed low values although they were positive and statistically significant. The highest correlation was observed when the QoL related to urinary symptoms and symptom scores (r = 0.61; P < 0.001) was analyzed. Conclusions A low correlation was found between the score lower urinary tract symptoms assessed by IPSS and the different volumes of the prostate gland (TV, TZV) and prostate TZI, and, on the other hand, an inverse correlation between the intensity of urinary symptoms and QoL, supporting the idea of multifactorial aspects related to the genesis of urinary symptoms in men.     

The use of cardiac computed tomography angiography in the assessment of percutaneous left atrial appendage closure – Review and experts recommendations endorsed by the Société française d’imagerie cardiaque et vasculaire diagnostique et interventionnelle

Atrial fibrillation is the most common cause of arrhythmia which is responsible for over 15% of ischemic strokes, most of these being secondary to migration of a left atrial appendage (LAA) thrombus. In patient with contraindication to anticoagulant therapy, percutaneous closure system placement may be indicated. Cardiac computed tomography (CT) angiography plays a central role in the initial assessment as well as in the follow-up. The purpose of the pre-implantation cardiac CT angiography is to evaluate the anatomy of the LAA in order to select the most suitable prosthesis and check for any contraindication to device implantation. Image analysis is divided into four steps that include analysis of the approach; search for a thrombus in the LAA; investigation of the anatomy of the LAA (morphology of the LAA, dimensions of the LAA and choice of device) and cardiac and thoracic assessments. Follow-up involves CT examination to check for correct placement of the device and to detect any complications. On the basis of the results of currently available published research, a panel of experts has issued recommendations regarding cardiac CT angiography prior to percutaneous LAA closure device placement, which were further endorsed by the Société française d’imagerie cardiaque et vasculaire diagnostique et interventionnelle (SFICV).     

Focal Therapy for Prostate Cancer: Possibilities and Limitations

Context

A significant proportion of patients diagnosed with prostate cancer have well-differentiated, low-volume tumors at minimal risk of impacting their quality of life or longevity. The selection of a treatment strategy, among the multitude of options, has enormous implications for individuals and health care systems.

Objective

Our aim was to review the rationale, patient selection criteria, diagnostic imaging, biopsy schemes, and treatment modalities available for the focal therapy of localized prostate cancer. We gave particular emphasis to the conceptual possibilities and limitations.

Evidence acquisition

A National Center for Biotechnology Information PubMed search (www.pubmed.gov) was performed from 1995 to 2009 using medical subject headings “focal therapy” or “ablative” and “prostate cancer.” Additional articles were extracted based on recommendations from an expert panel of authors.

Evidence synthesis

Focal therapy of the prostate in patients with low-risk cancer characteristics is a proposed treatment approach in development that aims to eradicate all known foci of cancer while minimizing damage to adjacent structures necessary for the preservation of urinary, sexual, and bowel function. Conceptually, focal therapy has the potential to minimize treatment-related toxicity without compromising cancer-specific outcome. Limitations include the inability to stage or grade the cancer(s) accurately, suboptimal imaging capabilities, uncertainty regarding the natural history of untreated cancer foci, challenges with posttreatment monitoring, and the lack of quality-of-life data compared with alternative treatment strategies. Early clinical experiences with modest follow-up evaluating a variety of modalities are encouraging but hampered by study design limitations and small sample sizes.

Conclusions

Prostate focal therapy is a promising and emerging treatment strategy for men with a low risk of cancer progression or metastasis. Evaluation in formal prospective clinical trials is essential before this new strategy is accepted in clinical practice. Adequate trials must include appropriate end points, whether absence of cancer on biopsy or reduction in progression of cancer, along with assessments of safety and longitudinal alterations in quality of life.     

人工寰齿关节置换与Magerl经关节螺钉固定的生物力学比较

[目的]测试人工寰椎齿状突关节置换后寰枢椎的稳定性和功能,并与Magerl经关节螺钉固定进行比较.[方法]将12例新鲜的成人头颈部标本随机分为两组,第1组在齿状突切除术后使用人工寰齿关节置换;第2组在齿状突切除术后使用Magerl经关节螺钉固定.对两组的每一标本分别测定完整状态、人工关节置换术后或经关节螺钉固定后的运动范围和中性区.[结果]人工关节置换术后与完整状态相比前屈、后伸、左右侧屈的运动范围和中性区明显减小(P＜0.05),左右旋转的运动范围无显著差异(P＞0.05),中性区增大(P＜0.05).Maged经关节螺钉固定后与完整状态相比前屈、后伸、左右侧屈及左右旋转的运动范围和中性区均明显减小(P＜0.05).人工关节置换术后及Magerl经关节螺钉固定后两组在前屈、后伸及左右侧屈的ROM稳定指数和NZ稳定指数相比均无显著差异(P＞0.05).[结论]实验证实在齿状突切除后,进行自行设计的人工寰椎齿状突关节置换可取得与Magerl经关节螺钉固定相似的前屈、后伸及左右侧屈稳定性,重要的是与完整状态相比左右旋转的运动范围无显著差异,最大限度的保留了寰枢复合体重要的旋转功能,对以往齿状突切除、脊髓减压后需要使用寰枢椎融合的患者,提供了另一种术式的选择.