An unexpected complication following immunoadsorption with a staphylococcal protein a column

Extracorporeal immune adsorption with staphylococcal protein A (SPA) columns can remove immune complexes and immunoglobulins in the treatment of a variety of diseases. We present the case of an elderly man with neuropathy associated with monoclonal gammopathy, treated by 3 on-line SPA procedures. At the completion of these treatments his neuropathy relapsed, progressing to near-total paralysis. Return to a baseline clinical status required several months. The reason for this severe relapse is not clear. Possible explanations include SPA activation of T-lymphocytes, with release of gamma interferon and increased antigen recognition, or removal of an anti-idiotype control mechanism. We advise caution in the application of immunoadsorption to conditions in which it has not yet been evaluated. © 1992 Wiley-Liss, Inc.     

科学设置栏目打造医学期刊品牌——兼谈《磁共振成像》栏目设置

栏目是杂志对稿件进行分类管理的一种重要手段。优秀的栏目要依据办刊宗旨和杂志定位,结合稿源情况和市场需求进行科学的设置。本文结合《磁共振成像》杂志栏目设置,探讨打造期刊品牌的途径。     

周围神经损伤后再生的药物调控研究

目的　探讨神康灵对损伤的坐骨神经再生的作用。方法　采用 2 8只成年体重为 2 0 0g的Wistar大鼠 ,随机分成 2组 (实验组和对照组 ) ,分别于术后 4周和 6周 ,通过肌电图检测坐骨神经运动诱发电位的传导速度和波幅 ;组织学检测有髓神经轴突数目、横截面积 ,从而探讨神康灵对坐骨神经损伤后再生的作用。结果　实验组神经传导速度、再生的有髓神经纤维横截面积、数目均优于对照组。结论　神康灵对坐骨神经损伤后的再生有明显的促进作用。     

抗体介导骨再生的研究进展

骨缺损传统的治疗方法 主要是通过移植自体骨或异体骨,这具有显著的潜在发病率等弊端.重组人骨形态发生蛋白(rhBMP)-2已被美国食品和药物管理局批准用于特定的再生适应症.然而,骨组织工程中通过外源生长因子的给药方式有许多缺点.2011年有学者针对其弊端提出了抗体介导的骨再生(AMOR),即局部使用抗体,该抗体可以将内源...     

Objective determination of pH thresholds in the analysis of 24 h ambulatory oesophageal pH monitoring

In 24 h oesophageal pH monitoring, pH 4 is widely but arbitrarily used as the threshold between reflux and non-reflux pH values. The aim of the study was to define pH thresholds objectively, based on Gaussian curve fitting of pH frequency distributions. Single-channel 24 h oesophageal pH monitoring was performed in 26 healthy volunteers and 26 patients with pathological gastro-oesophageal reflux, and five-channel pH-metry was performed in 14 healthy volunteers and 14 patients. The calculated pH thresholds varied between healthy volunteers from 5.0 to 6.4 in the upright position and from 4.5 to 5.7 in the supine position, but were constant between different oesophageal recording sites. In 15 and nine patients (single-channel and five-channel pH-metry respectively), pH thresholds could not be determined at the distal oesophageal sites. However, the calculated pH thresholds in the proximal oesophagus were in the same range as in the control subjects. The authors conclude that the use of the conventional threshold of pH 4 leads to underestimation of the extent of gastro-oesophageal reflux, but are reluctant to advocate the use of higher thresholds in clinical practice.     

Stem cells for tendon tissue engineering and regeneration

Importance of the field: Tendon injuries are common especially in sports activities, but tendon is a unique connective tissue with poor self-repair capability. With advances in stem cell biology, tissue engineering is becoming increasingly powerful for tissue regeneration. Stem cells with capacity of multipotency and self-renewal are an ideal cell source for tissue engineering.

Areas covered in this review: This review focus on discussing the potential strategies including inductive growth factors, bio-scaffolds, mechanical stimulation, genetic modification and co-culture techniques to direct tendon-lineage differentiation of stem cells for complete tendon regeneration. Attempting to use embryonic stem cells as seed cells for tendon tissue engineering have achieved encouraging results. The combination of chemical and physical signals in stem cell microenvironment could be regulated to induce differentiation of the embryonic stem cells into tendon.

What the reader will gain: We summarize fundamental questions, as well as future directions in tendon biology and tissue engineering.

Take home message: Multifaceted technologies are increasingly required to control stem cell differentiation, to develop novel stem cell-based therapy, and, ultimately, to achieve more effective repair or regeneration of injured tendons.     

Myocardial regeneration in heart failure: integrated development of biological therapeutic approaches

Heart failure currently constitutes one of the greatest health problems in the Western world. Its incidence, far from diminishing or even remaining stable, is actually still increasing in association with the aging of the population and its lifestyle. A better knowledge of physiopathological mechanisms has allowed for the development of new therapeutic focal points and lines of research. Nevertheless, its treatment is complex and encompasses a multidisciplinary approach. Patients in an advanced stage still have a very high mortality rate in spite of receiving optimum medical care. The development of new therapeutic techniques that afford a better prognosis has therefore been essential. Of these, and leaving aside surgical treatments, myocardial regeneration by means of cellular therapy, new concepts in tissue engineering and their results, and the applications of new advances in the field of immunomodulation have all recently experienced development. In this article, the aim is to bring the latest concepts in the physiopathology and humoral response of cardiac failure up to date as well as doing the same with the therapeutic approaches in this area.     

Microprocessor-based near real-time bedside blood chemistry monitor

Summary A microprocessor-based instrument which integrates the function of a volumetric infusion pump with a blood chemistry analyzer has been developed. Presently, the instrument is capable of measuring Na⁺, K⁺, Ca⁺⁺ and pH within approximately 40 sec at a frequency of up to every 2 min. The system is set up as an intravenous (IV) infusion pump with the addition of an array of disposable sensors placed at the distal end of the IV set. An isotonic IV solution is used to keep the site patent while also serving as a calibrant for the sensors. The instrument first calibrates the sesors, then withdraws approximately 0.6ml of blood to come in contact with the sensors. Within approximately 15 sec, it displays the results, flushes the blood back into the patient and resumes normal infusion. There is no blood loss to the patient and no need to handle blood.The system was first validated with known aqueous controls and then used on-line in a variety of animal studies where dynamic fluctuation of electrolytes and pH occurred. Excellent correlation was found with off-line samples tested on conventional STAT analyzers. Some preliminary patient data is also presented.     

Biologically inspired approaches to drug delivery for nerve regeneration

As the biological processes governing nerve regeneration have become elucidated over the past decades, interest has developed in manipulating these processes to improve nerve regeneration. Drug delivery to the regenerating nerve has the potential for major clinical applications in neurodegenerative diseases, spinal cord injury and peripheral nerve injury or sacrifice. This article reviews the evolution of the field of drug delivery to the regenerating nerve, from simple local applications of neurotrophic agents in solution and osmotic pump delivery, to the existing approaches involving novel biomaterials and genetically manipulated cell populations. A discussion of the various known nerve growth-promoting agents, and the chemical considerations involved in their delivery, is included. A perspective on the role of tissue engineering approaches for nerve regeneration in the future is offered.     

Treatment of chronic dilated cardiomyopathy with immunoadsorption using the staphylococcal A-agarose column: a comparison of immunoglobulin reduction using two different techniques

Auto-antibodies to myocardial antigens have been implicated in the pathogenesis of chronic dilated cardiomyopathy (DCM). A protein A immunoadsorption affinity column system was used to remove IgG antibodies, particularly IgG3. Two techniques, the standard technique (T-1) used for removal of IgG Factor VIII inhibitors and a technique (T-2) designed to enhance IgG3 removal and address issues in venous access, minimize positive fluid balance, and adverse reactions were compared. A total of four patients were treated, two patients were treated for 5 consecutive days with each technique. T-2 resulted in larger, but not significantly so, IgG3 reduction (70% and 63%) than T-1 (53% and 59%). Both techniques lowered total IgG levels by >or=93%. Because of venous access problems, 60% of T-1 procedures reached the plasma volume target versus 100% for T-2. Positive fluid balance was significantly lower for T-2 (+507 +/- 465) ml versus T-1 (+2,206 +/- 724) ml. Overall adverse event (AE) rate (T-1:16, T-2:15) was similar between the techniques but demonstrated a statistically significant difference in the types of reactions that occurred. All AE were mild in nature, common to other apheresis procedures, and were easily managed. This small study, demonstrated that a modified technique (T-2) with superior fluid balance should be used when treating DCM with the Immunosorba system.     

Stem cell therapy for cartilage regeneration in osteoarthritis

Enhancing the regeneration potential of hyaline cartilage tissue remains a great challenge. During embryonic development, some of the cells of the inner cell mass will turn into the mesoderm. This will be the founder of the mesenchymal cells in connective tissues of adult life, such as bone, tendon, muscle, and cartilage. Some of these embryonic mesenchymal cells are believed not to differentiate, but reside in each of the tissues. These are now collectively described as adult mesenchymal stem cells, which are thought to be capable of repairing injured tissue. We will briefly summarize the current knowledge about stem cell-related cells in cartilage tissue and carefully discuss the potential of the cell population we described recently as a starting-point for a regenerative therapy for osteoarthritis. We found that repair tissue from human articular cartilage during the late stages of osteoarthritis harbors a unique progenitor cell population, termed chondrogenic progenitor cells (CPC). These exhibit stem cell characteristics combined with a high chondrogenic potential. They offer new insights into the biology of progenitor cells and may be relevant in the development of novel therapeutic approaches for a cell-based therapy for late stages of osteoarthritis.     

Duodenal bulb pH in normal subjects

Four pH electrodes strapped together at 1 X 5 cm intervals were positioned in the pyloric region. Electrodes situated in the stomach record steady acid pH while electrodes distal to the pylorus show fluctuating pH, thereby enabling the electrodes to be localized from the pH pattern. Digital pH values were sampled and stored at a rate of 2/s from each electrode. For each 10-min period, the mean hydrogen ion activity, the percentage of time that the pH was at less than 3.0 and number of pH spikes were computed. Fourteen healthy subjects were studied in the fasting state and for 3 h after 300 ml chocolate milk. Log mean hydrogen ion activity in the proximal part of the duodenal bulb was (median and interquartile range): fasting pH 2.40 (2.23-3.00); 0-60 min after meal: pH 5.7 (4.92-5.95); 60-120 min: pH 2.31 (1.95-3.20) 120-180 min: pH 2.20 (1.99-2.44). Repeated studies in twelve subjects showed a linear correlation between 1st and 2nd study, r = 0.87. A significant linear correlation was found between peak acid output to pentagastrin and postprandial bulb acidity.     

Adipose-derived stem cell therapies for bone regeneration

Introduction: Cell-based therapies exploit the heterogeneous and self-sufficient biological environment of stem cells to restore, maintain and improve tissue functions. Adipose-derived stem cells (ASCs) are, to this aim, promising cell types thanks to advantageous isolation procedures, growth kinetics, plasticity and trophic properties. Specifically, bone regeneration represents a suitable, though often challenging, target setting to test and apply ASC-based therapeutic strategies.

Areas covered: ASCs are extremely plastic and secrete bioactive peptides that mediate paracrine functions, mediating their trophic actions in vivo. Numerous preclinical studies demonstrated that ASCs improve bone healing. Clinical trials are ongoing to validate the clinical feasibility of these approaches. This review is intended to define the state-of-the-art on ASCs, encompassing the biological features that make them suitable for bone regenerative strategies, and to provide an update on existing preclinical and clinical applications.

Expert opinion: ASCs offer numerous advantages over other stem cells in terms of feasibility of clinical translation. Data obtained from in vivo experimentation are encouraging, and clinical trials are ongoing. More robust validations are thus expected to be achieved during the next few years, and will likely pave the way to optimized patient-tailored treatments for bone regeneration.     

76例脊柱真空现象的CT诊断

目的观察发生在脊柱各部位的真空现象,总结其CT特征,探讨其临床意义。方法使用GE公司Hispeed双排螺旋CT机,分析76例有脊柱真空现象病人的CT表现。颈椎、胸椎、腰椎的椎体及间盘扫描采取不同的层厚及层间距。结果总结脊柱真空现象发生的部位及各自CT表现:发生真空现象的部位以椎间盘最为多见。其共同点为脊柱相应部位出现低密度气体影。结论脊柱不同部位的真空现象可分别反映椎间盘、椎体及小关节的退变、椎体的骨质疏松及外伤后改变等特征,具有重要的临床意义。     

Intragastric pH measurement using a novel disposable sensor

An unique disposable pH sensor molded into the end of a nasogastric tube was tested in twelve healthy human volunteers. A Spearman's rank corelation coefficient (r _s) of 0.90 was observed for the sensor and an indwelling miniature glass membrane electrode. The sensor did not correlate as well with aspirated stomach fluid (r _s=0.68). No sensor calibration was necessary and the sensors measured ±0.1 pH in laboratory pH buffers before and after the clinical study. Both bare and shielded disposable sensors closely agreed with a shielded miniature glass electrode.     

十二指肠溃疡胃内pH昼夜变化

目的 :探讨胃内pH昼夜变化对十二指肠溃疡 (Duodenalulcer ,DU)发病的影响。方法 :采用BioSTARpH动态检测仪 ,对 3 2例DU患者及 10名健康志愿者进行 2 4h胃内 pH监测 ,观察昼夜胃内pH <1、pH >3及 pH >4的时间百分比 ,pH >4的最长持续时间 ,进餐后胃内 pH的变化及持续时间等 ,并在DU组与对照组间进行比较。 结果 :DU组胃内pH <1的时间百分比增加 ,与健康对照组比较昼夜均有显著性差异 (P <0 0 1) ;DU组胃内 pH >3所占时间的百分比与对照组比较 ,白天无显著差异 ,夜间差异有显著性 (P <0 0 5 ) ;白天胃内 pH >4的总持续时间两组无显著性差异 ,夜间胃内 pH >4的总持续时间 ,两组无显著差异 ,夜间胃内pH >4的总持续时间DU组减少 ,两组间有显著性差异 (P <0 0 5 )。进餐后胃内的 pH均明显升高 ,升高幅度DU组与对照组无显著差异 ,pH升高的持续时间DU组缩短 ,两组有显著性差异 (P <0 0 5 )。结论 :DU患者昼夜均存在胃酸分泌亢进 ,且以夜间明显 ,而夜间胃酸分泌增加可能对DU的形成更有意义。提示抑酸治疗对DU患者的必要性以及提高夜间胃内 pH对DU患者的重要性。     

脊柱损伤的MRI分析与诊断

目的：分析和总结脊柱损伤的MRI表现和诊断意义。方法：80例脊柱外伤患者均作MRI检查。结果：80例中颈椎25例，胸椎26例，腰椎29例，其中包括椎骨骨折，椎体脱位，椎间盘突出，韧带损伤，脊髓损伤。结论：通过MRI对脊柱损伤的观察和诊断既能明确的显示脊髓、韧带、椎间盘和椎旁软组织受损伤的细节，还能明确椎骨受伤的情况。     

Adipose-derived stem cells for the regeneration of damaged tissues

As the promise of stem cell-based therapies begins to be realised, and efforts to bring advances to the clinic mount, the source of these cells is increasingly important. The morbidity associated with harvesting stem cells from solid organs and the invasive nature of bone marrow biopsies may limit their practicality for wider clinical applications. An emerging body of literature suggests that adipose tissue may provide an abundant, readily accessible source of cells with similar potential to that described of other adult stem cells. This review will address advances in the use of adipose stem cells in fields as divergent as soft tissue reconstruction and cerebral infarction recovery. Numerous challenges will also be discussed; however, rapidly accumulating advances suggest that adipose stem cells may be as effective as they are abundant.