Blood cell filtrability: reference values and clinical applications

In 500 healthy individuals cell deformability, expressed as cell filtration rate in microliters/s was studied with a microcirculation method in order to determine reference values for this method for various age groups in adults. The overall normal red cell filtration rate (RFR) value in healthy individuals was 69 +/- 11 microliters/s. When one compared the age groups 20-29 and 60-69 years, the reductions for RFR, white cell filtration rate (WFR), plasma-white cell filtration rate (P-WFR) and whole-blood filtration RATE (WBFR) was 26 +/- 3 (p less than 0.01), 32% +/- 5 (p less than 0.01), 28% +/- 4 (p less than 0.01) and 28% +/- (p less than 0.01) respectively. The reduction of RFR was graded into four clinical classes (GCTA = Gothenburg Cardio-Thoracic Association); I = 1-24%, II = 25-49%, III = 50-74%, IV = 75-100%, class I with lowest and class IV with highest reductions. Significant reductions in the mean RFR were noted in patients undergoing heart surgery (36% +/- 3, P less than 0.01, class II), patients with cardiac arrest (55% +/- 5, p less than 0.01, class III), occlusive arterial disease (58% +/- 6, p less than 0.001, class III) diabetes (45% +/- 5, p less than 0.01, class II). None of the patients had a normal RFR value. This study demonstrated a loss of cell deformability with age and disease.     

Islet cell transplantation

Diabetes is an autoimmune disease that causes destruction to the islet cells in the pancreas. The pancreas has two functions: islet cells make insulin (a hormone) and digestive enzymes to break down carbohydrates. Diabetes has two classifications: type I and type II. Type I diabetes is insulin-dependent, and type II is noninsulin dependent. Islet cell transplantation is focusing only on type I diabetes. Diabetes is a debilitating disease that has devastating effects on people. Those who have type I diabetes cannot make insulin and are completely dependent on adjusting their blood sugars by exogenous insulin (insulin shots). If these people were offered a better lifestyle, becoming free from having to take insulin shots, would most diabetics take the risk?Islet cell transplantation is an experimental procedure that is not relatively new and could offer a person with diabetes a better lifestyle. The only problem is that this is an experimental procedure, and the recipients must weigh the risks to the benefits. Some risk factors are having to take insulin shots daily and having to normalize blood sugars. The presenter suggested that islet cell transplantation is a risk work taking.     

自建微阵列化学发光免疫分析法定量检测心肌肌钙蛋白I自身抗体及其初步临床应用

目的基于微阵列蛋白质芯片技术建立定量检测心肌肌钙蛋白I自身抗体(cTnIAAb)的微阵列化学发光免疫分析法,并评价该方法的检测性能。方法以心肌肌钙蛋白I(cTnI)-C融合蛋白为检测抗原,对抗原点样浓度、封闭液、封闭时间和二抗进行筛选,以检测结果信噪比最大为标准优化条件。以100名健康体检者(正常对照组)cTnIAAb检测灰度值的第95百分位数为临界值,建立cTnIAAb检测的标准曲线,并评价微阵列化学发光免疫分析法的检测性能(稳定性、精密度、最低检测限、线性范围等)。采用微阵列化学发光免疫分析法检测500例血清cTnI>0.1 ng/mL的急性冠状动脉综合征(ACS)患者(ACS组)的血清cTnIAAb,采用免疫印迹法验证其特异性。结果最优实验条件:抗原点样浓度为50μg/mL,封闭液为2%人乳,最佳封闭时间为12 h,二抗为辣根过氧化物酶(HRP)-羊抗人IgG抗体。微阵列化学发光免疫分析法检测高、低值cTnIAAb的精密度良好,变异系数(CV)均<15%;空白限(Lo B)、检测限(LoD)分别为0.12、0.23 AU/mL;线性范围为0.23~815.00 AU/mL。免疫印迹法结果显示,cTnIAAb阳性样本和阳性对照在相对分子质量40000~55000处均出现特异性条带。ACS组血清cTnIAAb阳性率为8.4%(42/500),明显高于正常对照组[2%(2/100)](χ²=5.023,P<0.05);但血清cTnIAAb浓度2个组之间差异无统计学意义(P>0.05)。Spearman相关性分析结果显示,ACS组cTnIAAb与cTnI无相关性(r²=0.1,P>0.05)。结论自建的定量检测cTnIAAb的微阵列化学发光免疫分析法具有良好的检测性能,可为cTnIAAb的临床应用提供较好的方法学基础。     

Islet cell function: alpha and beta cells--partners towards normoglycaemia

Under normal conditions, insulin and glucagon are counter-regulatory hormones whose balanced action exhibits a relationship that ensures normoglycaemia. Elevated glucose levels following a meal stimulate pancreatic islet beta cells to secrete insulin and islet alpha cells to downregulate production of glucagon. With declining glucose and insulin levels, alpha-cell production of glucagon is increased to stimulate hepatic glucose production, preventing fasting hypoglycaemia. In type 2 diabetes mellitus (T2DM), beta-cell insulin response to glucose is blunted, including absence of early acute response, and alpha-cell response to glucose is impaired, resulting in absolute or relative hyperglucagonaemia and inappropriate hepatic glucose output that contributes to fasting hyperglycaemia. These changes are associated with structural and functional changes in pancreatic islets, including reduced beta-cell mass and reduced beta-cell:alpha-cell ratio. The role of the incretin hormone glucagon-like peptide-1 (GLP-1) in regulating glucose-dependent beta-cell insulin production and glucose-dependent alpha-cell glucagon production has been used to develop GLP-1-based therapies. These therapies may reduce the imbalances among insulin and glucagon that characterise T2DM, resulting in improved glycaemic control.     

Osmotic regulation of cell function and possible clinical applications

Inflammation and immunosuppression can cause acute respiratory distress syndrome, multiple organ failure, and sepsis, all of which are lethal posttraumatic complications in trauma patients. Prevention of the inflammation and immunosuppression has been a main focus of trauma researcher for many years. Recently, hypertonic resuscitation has attracted attention as a possible therapeutic approach to counteract such deleterious immune responses in trauma patients. We have begun to understand how hypertonic fluids affect immune cell signaling, and a number of experimental and clinical studies have started to reveal valuable information on the clinical efficacy and the limitations of hypertonic resuscitation fluids. Knowledge of how osmotic cues regulate immune cell function will enable us to fully exploit the clinical potential of hypertonic resuscitation to reduce inflammatory and anergic complications in trauma patients.     

CD34 cell separation: from basic research to clinical applications

Summary Advances in the immunological identification of primitive haematopoietic cells have led to the development of various techniques for their characterisation and purification. The expression of the CD34 antigen by the stem cell compartment has been exploited for these purposes. Separation systems capable of isolating CD34+ cells on a large scale are finding use in the clinic. Areas of interest overlap for both researchers and clinicians, and efforts to mobilise, characterise, purify and transplant these cells continue. Different CD34 purification systems are reviewed, focusing on their possible applications in different research fields. Clinical results of CD34+ selection and the possible future applications of this technology in the clinic are also reported.     

Catalytic autoantibodies in autoimmune myocarditis: clinical and pathogenetic implications

AIM: To evaluate pathogenetic and clinical significance of autoantibodies (AAB) with catalytic activity in the serum of patients with autoimmune myocarditis (AM). MATERIAL AND METHODS: The study was made on the sera from 99 patients with AM of different course: malignant, benign, myocardiosclerosis (MCS). In addition to standard immunological parameters, the study was made of serum levels of anticardiomyosine-antiCM (protabzymes) and anti-DNA (DNA-abzymes) of AAB. After obtaining anti-CM and anti-DNA IgG-AT, we determined non-specific and specific proteolytic activity of anti-CM. RESULTS: Maximal specific activity of protabzymes was seen in 73% patients with malignant AM, it correlated with blood levels of anti-CM AAB, DNA-abzymes activity was very high in 45% patients. In MCS proteolytic activity of autoAT was absent in 61% patients. In benign AM occurrence of protabzymes was confirmed in 35% cases. Elevated DNA-hydrolyzing activity of DNA-abzymes occurred in 13% cases. The activity had no significant correlation with serum titers of AB. In MCS proteolytic activity of AAB was absent in 61% cases, but high activity of anti-CM AAB was in 28%. The activity of DNA-abzymes in 44% ranged considerably which, in seropositive cases, detected significant correlation with serum titers of DNA-binding autoAT. CONCLUSION: Evaluation of catalytic activity of AAB may be considered as a criterial test assessing the stage, clinical variants and severity of AM. It also permits formulation of the disease prognosis and its possible outcomes.     

HASTE: features and clinical applications

HASTE (half-Fourier acquisition single-shot turbo spin echo) is the single-section pulse sequence with high-resolution and moderate T2 contrast. Therefore it allows ultra fast acquisition, it is not influenced by respiratory motion, and it is insensitive to susceptibility effect because all of the data are from spin-echo. Although it is very suitable for visualization of fluid, it suffers from resolution loss of parenchyma which has relatively short T2 value and seems blurred. Recently it is recognized as one of the most powerful tool for imaging abdomen, especially for MRCP (Magnetic Resonance Cholangio-Pancreato-graphy). The features of HASTE and some examples of possible clinical application are shown.     

Leukocyte cell adhesion proteins: from molecular dissection to clinical applications.

Leukocyte adhesion is needed for a number of leukocyte functions like immunoglobulin synthesis, T and NK-cell-mediated cytotoxicity, phagocytosis by granulocytes, and cellular accumulation in inflamed tissue. Several cell surface molecules involved in leukocyte-leukocyte and leukocyte-target cell interactions have recently been identified and characterized. Both the polypeptide and carbohydrate portions are important in leukocyte interactions. It is becoming increasingly apparent that it is possible to interfere with the normal functions of the leukocyte adhesion glycoproteins, and such applications may become important in medicine.     

Surfactant: clinical applications.

Pulmonary surfactant is an important chemical component of the lung. It decreases surface tension in the alveolar cells to help stabilize the alveoli, and it may help prevent pulmonary edema. Currently, naturally and synthetically derived surfactants are being used to treat neonatal respiratory distress syndrome, a leading cause of death in premature infants. Surfactant is recommended for prophylactic therapy in infants weighing less than 1,350 g (3 lb) and in infants weighing more than 1,350 g who show signs of pulmonary immaturity and for rescue therapy in infants with respiratory distress syndrome. Surfactant is administered by endotracheal tube, and the recommended dose is 5 mg per kg. Three doses, given 12 hours apart, is the recommended regimen for prophylactic therapy. Rescue therapy consists of one dose of surfactant given at the onset of respiratory distress and another dose given 12 hours later.     

Proteomics: clinical applications.

The word proteomics was coined in 1997 to describe the changes in all proteins expressed by a genome. Several sophisticated techniques including two-dimensional electrophoresis, imaging, mass spectrometry, and bioinformatics are used in proteomics to identify, quantify, and characterize proteins. Clinical proteomics is the application ofproteomics techniques to the medical field. The main aim of this methodology is to identify proteins involved in pathological processes and to understand how illness can lead to altered protein expression. Clinical proteomics offers the opportunity and the potential to develop new diagnostic and prognostic tests, to identify new therapeutic targets, and eventually to allow the design of individualized patient treatment. Here we present an overview of proteomics applications to the study of disease and its potential to improve diagnosis and prognosis.     

Islet cell autoantigens in insulin-dependent diabetes.

A burgeoning number of antigenic targets of the islet cell autoimmunity in IDD have been identified, and more can be anticipated through improved methods for their identification. The challenge for those investigating the pathogenesis of IDD will be to assign the relative importance of these antigens to the development of the disease, and to resolve whether there is a dominant primary immunologic event that is followed by a series of secondary immunizations to a variety of normally sequestered islet cell antigens in the sequence of pathogenic events that culminate in IDD. One interesting observation that may have potential pathogenic implications is the observation that of all islet cell autoantigens described, only two (i.e., 64 kD/GAD, 38 kD) are reactive in their native configurations, implying that recognition of conformational epitopes is most important. This property argues for primary immunizing agents rather than secondary ones after release of denatured antigens and antigenic recognition through their epitopes. Given the complex and multiple physiological functions of islet cells and the continuous variation in their activity, it is reasonable to speculate that the speed of the progression to IDD could vary between individuals with respect to their insulin needs and the relative activities of their islets. Activated islets may express autoantigens that have only limited expression in quiescent islets. The often times striking variation in the severity of insulitis seen in different islets of a single pancreas may be explained by the level of activity of individual islets. Furthermore, disparity in HLA-DR/DQ associations with disease may involve differences in the immunological recognition of autoantigens. Whereas there is still much to learn, it is clear that disease predictability and disease intervention studies have been enhanced through the identification of the islet cell autoantigens in IDD.     

Osteocalcin: diagnostic methods and clinical applications

Osteocalcin is a small (Mr 5800), very interesting bone specific protein, synthesized by osteoblasts and measured in plasma as a biochemical indicator of bone formation. Many immunoassays for osteocalcin have been developed, including radio- and enzymoimmunoassays, with the use of monoclonal and polyclonal antibodies. These are used in many different clinical settings, including bone, kidney, and liver diseases. However, there is a wide range of published values for plasma osteocalcin concentrations in control and patient samples and this has hindered a more widespread adoption of osteocalcin measurement by clinicians. This review discusses how various immunoassays for osteocalcin may contribute to the wide variation of published values and suggests approaches for the development of standardized assays. For example, epitope specificity and immunoreactivity with multiple forms of osteocalcin and osteocalcin peptides in plasma are discussed. It also includes a recent update on interesting clinical applications of osteocalcin.