小胶质细胞M1/M2极化状态在脊髓损伤中作用的研究进展

脊髓损伤（SCI）是指由创伤、肿瘤、感染、畸形和医源性等因素引起的脊髓结构或功能受损,严重影响患者生活质量、功能状态和社会独立性。SCI发生后常会出现出血、局部休克、缺氧、三磷酸腺苷减少、小胶质细胞激活和促炎性细胞因子释放等。中国SCI发生率为15~60/百万,且呈逐年升高趋势^[1]。     

放射影像学检查无异常的颈椎脊髓损伤的临床研究进展

放射影像学检查无异常的颈椎脊髓损伤（SCI）是指X线片或CT未见骨折、脱位,但合并颈椎SCI症状的一种特殊类型的SCI^[1],国外最早报道见于儿童,占儿童SCI的3%~66%^[1-3] ;国内主要见于成人,并命名为无骨折脱位型颈椎SCI,占颈椎SCI的20%^[4]。放射影像学检查无异常的颈椎SCI均可导致不同程度瘫痪等严重后果,主要有完全横断性损伤、中央管综合征、脊髓半切综合征、不完全性SCI 4种类型^[1,3-6],临床症状为损伤平面以下感觉减退或异常、肌力下降以及膀胱功能障碍,部分可合并颈神经根损伤;成人以中央管损伤综合征最为常见^[4,7],损伤可表现为非连续性、延迟性,在3~7 d达到高峰,此时的MRI表现较入院时与最终愈后具有明显相关性^[8-9]。儿童和成人放射影像学检查无异常的颈椎SCI各具特点,两者在临床发病、MRI表现及治疗上存在明显差异,本文查阅国内外文献,就当前的临床研究进展作如下综述。     

颈椎椎间盘突出致脊髓半切综合征误诊为脑卒中1例报告

脊髓半切综合征(BSS)由Brown-Sequard于1849年首次提出^[1],是由外部压迫和内部病变等原因引起的一种罕见的脊髓不完全性损伤,通常发生在颈部^[2]。可由创伤(如枪伤、刺伤、骨折及椎体脱位)和非创伤(如肿瘤、硬膜外血肿、多发性硬化症、辐射等)引发^[3-5],因椎间盘突出导致的BSS相对较少^[6-7]。BSS表现为病变侧损伤平面以下深感觉障碍及上运动神经元性瘫痪;对侧损伤平面以下疼痛、温觉丧失^[8-9],有轻度到严重的神经功能受损。BSS占创伤性脊髓损伤的1%~4%^[10],国内外相关文献报道较少,主要为个案报道^[2,11]。本院急诊科于2020年10月22日收治1例因存在类卒中症状,初期被误诊为急性脑梗死,在下级医院进行过溶栓治疗的BSS患者,现对诊疗过程进行梳理分析,报告如下。     

寰枢椎脱位伴齿突后假瘤诊疗的研究进展

齿突后假瘤是由寰枢椎脱位或其他病因引起的炎性肉芽肿或反应性肥大导致齿突后软组织增生病变^[1]。其可压迫脊髓，导致疼痛、感觉异常，甚至瘫痪。引起齿突后假瘤较常见的病因有类风湿关节炎（RA）^[2-3]、寰枢椎脱位^[4]、颈椎退行性疾病^[5]，少见的病因有长期透析^[6]、晶体沉积^[7]、滑膜囊肿^[8]等。     

神经电生理监测下手术治疗腰段脊髓硬膜动静脉瘘1例报告

硬膜动静脉瘘（SDAVF）是位于硬膜背侧表面的神经根动脉与神经根静脉之间形成异常动静脉分流,进而引起静脉高压和扩张,使脊髓灌注减少甚至受压,导致脊髓缺血和水肿^[1-4]。SDAVF属于脊髓血管畸形,目前具体病因尚不清楚,可能与先天性血管畸形有关。好发于中年男性^[5-6],发生率为5/106~10/106,常累及胸腰段^[7],临床表现为感觉、运动功能逐步下降,有时伴有疼痛、括约肌功能失调,症状进行性加重^[8-11]。本院2022年2月17日收治1例经数字减影血管造影（DSA）检查确诊的SDAVF患者,手术治疗后患者症状明显缓解,现将诊疗过程进行总结,报告如下。     

自噬相关哺乳动物雷帕霉素靶蛋白信号通路在脊髓损伤中的作用研究进展

脊髓损伤（SCI）可导致严重且不可逆的神经功能缺损甚至终身瘫痪,其常见病因包括交通事故、坠落伤及重物砸伤等。SCI造成的神经系统创伤至今仍是脊柱外科的治疗难题。自噬是一种主要依赖溶酶体介导的分解代谢途径,可使功能失调的细胞成分降解以应对各种形式的压力^[1]。微管相关蛋白1轻链3Ⅱ（LC3Ⅱ）、Beclin-1和p62被认为是自噬的3种标志物,自噬通量的高低可以通过自噬标志物的水平来评估,LC3Ⅱ或LC3Ⅱ/LC3Ⅰ比值、Beclin-1增加以及p62蛋白表达减少都可以表明自噬水平上升^[2]。哺乳动物雷帕霉素靶蛋白（mTOR）是一种丝氨酸/苏氨酸蛋白激酶,是信号网络的核心和细胞生长的中央控制器,它在调节细胞代谢、死亡、存活和增殖方面发挥着重要作用,被认为是自噬的主要负调节因子^[3]。它与Raptor和Rictor蛋白亚基作用可形成2种不同复合物,即mTOR复合物1（mTORC1）和mTOR复合物2（mTORC2）^[4],其中,mTORC1在调节自噬方面发挥核心作用。同理,mTOR通路在神经系统调节中也发挥着重要作用,雷帕霉素在保护和神经修复中起关键作用,mTOR信号通路是调节自噬的核心中枢,在调节神经细胞的生长、存活、分化过程中起重要作用。抑制mTOR通路能限制星形胶质细胞瘢痕形成并增强自噬,从而延缓SCI的进展^[6]。因此,对mTOR通路的干预是改善SCI患者预后的重要方式之一。本文主要总结了自噬相关mTOR信号通路在SCI中作用的研究进展,以期为SCI患者的诊治提供参考。     

脊柱夏科特关节病1例报告

夏科特关节病又称神经性关节病,由于各种原发病,患者痛觉和位置觉丧失,不能本能地调整肢体位置,关节失去保护性反射,同时,关节区域的血管及破骨细胞异常增殖导致局部代谢紊乱,最终导致加速的严重关节退行性变,表现为骨与软骨的破坏、关节面崩解和关节脱位^[1-2]。不同的原发病有不同的好发部位,脊髓痨患者好发于脊柱关节,脊髓空洞患者好发于上肢的肩关节、肘关节和腕关节,糖尿病患者则好发于足、踝关节^[3]。脊柱夏科特关节病（CSA）目前国内相关报道较少。本院收治1例胸椎脊髓损伤后继发CSA及髋关节病变的患者,现将诊疗过程报告如下。     

生物相容高分子水凝胶在椎间盘修复再生方面作用的研究进展

椎间盘退行性变为慢性疾病,会导致脊柱承重不稳,进而损伤脊髓、马尾神经和神经根,60%的70岁以上老年人群会发病^[1-2]。由于椎间盘退行性变的病理学、病理生理学及生物力学机制并不完全清楚,目前的治疗手段仅能减轻疼痛症状,不能完全消除疾病^[3-4]。椎间盘切除术和椎间融合术是治疗椎间盘退行性变的常用术式,但易造成脊柱生物力学的改变^[5]。人工椎间盘可应用于椎间盘退行性变的治疗,但因椎间盘的结构和功能复杂,很难设计出理想的椎间盘假体来保持天然组织结构和生物力学特征。理想的生物组织替代物应具有高强度、高柔性和高韧性^[6]。     

颈椎脊索瘤术后5次迟发性出血1例报告

椎动脉出血（VAH）是颈椎手术中或术后出现的一类极为罕见的并发症,大出血可导致中枢神经系统永久性损伤,甚至导致患者死亡,其发生率为0.20%～1.96%^[1-5]。有研究^[3-5]表明,VAH多发生于颈椎退行性疾病的前路手术显露及后路手术椎弓根置钉等过程。目前VAH的文献报道较少,尚无确切的治疗方式。本院收治1例颈椎脊索瘤术后单侧椎动脉反复出血5次的病例,通过总结其诊疗经过探讨VAH的原因及诊治措施,现报告如下。     

微RNAs在脊髓缺血再灌注损伤中的研究进展

脊髓缺血再灌注损伤(SCII)是胸、腹主动脉术后最严重的并发症之一,可导致严重的神经功能障碍,甚至瘫痪^[1]。SCII主要包括缺血和再灌注2个阶段,缺血发生在体内大动脉阻断或循环停止期间,再灌注包括活性氧和炎性细胞因子的释放以及细胞凋亡^[2]。SCII的具体发生机制目前尚不清楚,近年来,对SCII的病因和发生机制的研究主要包括氧自由基介导的脂质过氧化损伤、炎性反应^[3-5]、细胞内Ca²⁺超载^[6-7]、以谷氨酸盐为主的兴奋性氨基酸的毒性作用^[8]、细胞凋亡^[9-10]和细胞自噬^[11-12]等。微RNA(miRNA)是一类长度为19~25个核苷酸的非编码单链RNA,可以通过和其靶mRNA的3''非编码区(3''-UTR)上的互补核苷酸配对来抑制mRNA或蛋白质的合成,调控靶基因的表达,从而进一步调节细胞的生长、增殖、分化和凋亡^[13]。靶基因的抑制或降解主要取决于miRNA与其靶基因的互补程度,如miRNA与目标mRNA部分配对,会抑制蛋白质合成;如miRNA与其靶mRNA完美(或接近完美)配对,则会导致mRNA降解。单个miRNA可以靶向数百个mRNA,并影响许多基因的表达。据统计,miRNAs能够调节人类基因组中多达30%的编码基因^[14]。此外,miRNAs的作用机制涉及多种重要过程,包括凋亡、分化、发育、增殖和信号转导等。miRNAs已被证实与许多疾病的发生有关,包括自身免疫性疾病(如哮喘、嗜酸性食管炎、过敏性鼻炎和湿疹)^[15]、癌症^[16]、糖尿病及心血管疾病^[17-18]、骨骼肌肉疾病^[19]。miRNAs因在细胞液中的稳定性、在人类和哺乳动物之间的保守性和组织特异性成为重要的生物标志物,在调节神经系统疾病(包括SCII)中发挥着至关重要的作用^[20-21]。     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

Reduction of Plasma Fibrinogen, Immunoglobulin G, and Immunoglobulin M Concentrations by Immunoadsorption Therapy with Tryptophan and Phenylalanine Adsorbents

Abstract Immunoadsorption (1A) therapy with tryptophan (TR-350) or phenylalanine (PH-350) adsorbents has been used to reduce the concentration of serum antibodies in human lymphocyte antigen (HLA)-immunized patients. Other forms of plasma purification have been reported to reduce the level of fibrinogen, which affects the blood properties. In this study we investigated the effects of IA therapy using both adsorbents on plasma fibrinogen and immunoglobulins G and M in 13 patients (8 patients were treated with TR-350, and 5 patients were treated with PH-350). During each session 1 plasma volume (2.8 ± 0.4 L of plasma) was processed through the immunocolumn and then returned to the patient together with the blood cells. Compared with the pretreatment values, the plasma fibrinogen, IgG, and IgM concentrations were significantly reduced after IA therapy (p < 0.01 for TR-350; p < 0.04 for PH-350). There was a positive correlation between the degree of reduction of plasma proteins and the number of IA treatments given. A nonpara-metric test (Wilcoxon's signed-rank test or the Mann-Whitney test) was used for statistical analysis. We conclude from our study that IA therapy effectively lowers the plasma levels of fibrinogen, IgG, and IgM and thus can be considered a valuable alternative to other blood purification methods.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.     

The analgesic effect of racemic ketamine in patients with chronic ischemic pain due to lower extremity arteriosclerosis obliterans

Background : Ketamine in sub-dissociative doses has been shown to have analgesic and phantom-Limb pain, where conventional treatment has often failed. Chronic ischemic pain due to lower extremity arteriosclerosis obliterans often responds poorly to analgesics, and the pain-generating mechanisms are not well understood.
Methods : Eight patients with rest pain in the lower extremity due to arteriosclerosis obliterans were given sub-dissociative doses of 0.15, 0.30, or 0.45 mg/kg racemic ketamine and morphine 10 mg as a 5-min infusion on four separate days in a cross-over, double-blind, randomised protocol. Plasma levels of (S)- and (R)-ketamine and their nor-metabolites were analysed with an enantioselective high-performance liquid chromatography (HPLC) method. Pain levels were evaluated with a visual analogue scale (VAS).
Results : Individual pain levels were highly variable during and after all the infusions but the pooled pain levels showed a dose-dependent analgesic effect of ketamine with a transient but complete pain relief in all patients at the highest dose (0.45 mg/ kg). Side-effects, mainly disturbed cognition and perception, were pronounced and dose-dependent. Morphine 10 mg had an analgesic peak at 20 min and 5/8 patients had complete pain relief. The remaining 3 patients also had high baseline pain scores, indicating a higher analgesic potency for the 0.30 and 0.45 mg/ kg ketamine doses than for morphine 10 mg.
Conclusion : We have demonstrated a potent dose-dependent analgesic effect of racemic ketamine in clinical ischemic pain. Due to a narrow therapeutic window, this analgesic effect is probably best utilised in combination with other analgesics.     

Intravenous endotoxin does not increase tissue extravasation of albumin in rats

Background : It is unclear whether activation of the inducible nitric oxide synthase (iNOS) increases or decreases the extravasation of plasma.
Methods : Chloralose anaesthetised male Wistar rats received E. coli lipopolysacharide (LPS), 3 mg kg^-1 i.v., or the corresponding volume of saline, 3 or 5 h before the end of the experiment. Mean arterial pressure (MAP) and heart rate (HR) were recorded. Tissue clearance of radio-labelled albumin, during the last 2 h of each experiment, was determined by a double-isotope method. In separate animals, the serum concentration of nitrite and nitrate was determined, 5 h after LPS or the solvent.
Main Results : LPS initially decreased MAP and lastingly increased HR. In the 3-h LPS animals (n=8), tissue plasma clearance was lower in the heart and calf muscle and increased only in diaphragm, compared to corresponding control animals (n=8). In the 5-h LPS rats, clearance was lowered (n=8) in the entire gastrointestinal tract and in testes, compared to controls (n=8). The serum nitrite/nitrate concentration was higher in animals given LPS (n=6) than in controls (n=6).
Conclusion : After LPS, tissue clearance of albumin was not increased in any major tissue, in spite of increased serum levels of NO end products. Apparently, after activation of iNOS, the augmented release of NO is not necessarily associated with increased albumin extravasation.     

Adrenaline markedly improves thoracic epidural analgesia produced by a low-dose infusion of bupivacaine, fentanyl and adrenaline after major surgery: A randomised, double-blind, cross-over study with and without adrenaline

Background: Basic pharmacological research indicates that there are synergistic antinociceptive effects at the spinal cord level between adrenaline, fentanyl and bupivacaine. Our clinical experience with such a mixture in a thoracic epidural infusion after major surgery confirms this. The objectives of the present study were to evaluate the effects on postoperative pain intensity, pain relief and side effects when removing adrenaline from this triple epidural mixture. Methods: A prospective, randomised, double-blind, cross-over study was carried out in 24 patients after major thoracic or abdominal surgery. Patients with only mild pain when coughing during a titrated thoracic epidural infusion of about 10 ml · h^?1 of bupivacaine 1 mg · ml^?1, fentanyl 2 μg · ml^?1, and adrenaline 2 μg · ml^?1 were included. On the 1^st and 2^nd postoperative days each patient was given a double-blind epidural infusion, at the same rate, with or without adrenaline. The effect was observed for 4 h or until pain when coughing became unacceptable in spite of a rescue analgesic procedure. Rescue analgesia consisted of up to two epidural bolus injections per hour and i.v. morphine if necessary. All patients received rectal paracetamol 1 g, every 8 h. Fentanyl serum concentrations were measured with a radioimmunoassay technique at the start and end of each study period. Main outcome measures were extent of sensory blockade and pain intensity at rest and when coughing, evaluated by a visual analogue scale, a verbal categorical rating scale, the Prince Henry Hospital pain score, and an overall quality of pain relief score. Results: The number of hypaesthetic dermatomal segments decreased (P <0.001) and pain intensity at rest and when coughing increased (P <0.001) when adrenaline was omitted from the triple epidural mixture. This change started within the first hour after removing adrenaline. After 3 h pain intensity when coughing had increased to unacceptable levels in spite of rescue analgesia (epidural bolus injections and i.v. morphine). Within 15–20 min after restarting the triple epidural mixture with adrenaline, pain intensity was again reduced to mild pain when coughing. Serum concentration of fentanyl doubled from 0.22 to 0.45 ng · ml^?1 (P <0.01), and there was more sedation during the period without adrenaline. Conclusions: Adrenaline increases sensory block and improves the pain-relieving effect of a mixture of bupivacaine and fentanyl infused epidurally at a thoracic level after major thoracic or abdominal surgery. Serum fentanyl concentrations doubled and sedation increased when adrenaline was removed from the epidural infusion, indicating more rapid vascular absorption and systemic effects of fentanyl.     

The multiply injured child

Blunt trauma is the principal cause of childhood death in many developed countries. This review outlines the differences between adults and children with respect to resuscitation and treatment of orthopaedic injuries in a child with polytrauma. Recent advances in techniques of fracture stabilization are reported.     

Utilisation des médicaments prokinétiques en réanimation : indications et limites ?

Enteral feeding is often limited by gastric and intestinal motility disturbances in critically ill patients, particularly in patients with shock. So, promotility agents are frequently used to improve tolerance to enteral nutrition. This review summaries the pathophysiology, presents the available pharmacological strategies, the clinical data, the counter-indications and the principal limits. The clinical data are poor. No study demonstrates a positive effect on clinical outcomes. Metoclopramide and erythromycin seems to be the more effective. Considering the risk of antibiotic resistance, the first line use of erythromycin should be avoided in favor of metoclopramide.