A strategy for the comparative analysis of serum proteomes for the discovery of biomarkers for hepatocellular carcinoma

Many of the emerging technologies for the global evaluation of gene expression, at both the RNA and protein level, are being applied to the problem of finding biomarkers for human disease progression. These analyses can be made difficult, however, by variation between samples that arises from both technical and nondisease related physiological or genetic causes. In an effort to identify serum polypeptides whose presence or absence correlates with the clinical status of patients at high risk for hepatocellular carcinoma (HCC), we have developed a strategy that helps to focus the analysis on meaningful changes in protein levels above the background of variation. For the current study we divided the patient population into four clinically defined diagnostic groups that represent a generally increasing risk for HCC. Chronic infection with hepatitis B virus (HBV) is a major risk factor for HCC and our groups included patients with no indication of liver disease (healthy), those with inactive chronic HBV, those with active chronic HBV, and patients with a diagnosis of HCC and history of chronic HBV infection. Serum polypeptides from these patients were first analyzed in two-dimensional gels by combining the serum from patients in each of the four groups to generate composite gel profiles. Analysis of these composite gels allowed us to identify two relatively abundant features that were reduced in the HCC group as compared to the healthy group. Tryptic fragment mass fingerprinting identified the features as a carboxy terminal fragment of complement C3 and an isoform of apolipoprotein A1. These two features were examined by two-dimensional gel electrophoresis of serum from each individual in the four groups in order to verify that the inter-group differences seen in composite gels reported changes in abundance for most members of the group, rather than extreme changes for a small fraction of the group. These preliminary studies suggest that a proteomic methodology can be used for the identification of serum biomarkers for HCC and other liver disease.     

A Procedure for the Design of Novel Assisting Devices for the Sit-to-Stand

The Sit-to-Stand （STS） is an activity most people perform numerous times daily. Standing up deals with the transition from two stabilized postures, namely seated to standing, with movement of all body segments except the feet. During the STS the body＇s Center of Gravity （COG） is moved upward from a sitting position to a standing position without losing balance and requiring a good coordination of many muscles. Three main phases of the STS movement can be recognized. One begins to stand up by inclining the upper body forward, which moves body mass toward the feet in order to maintain balance after lift-off. Prior to leaving the chair, hip and knee extensor muscles are activated to provide antigravity support for these joints, this action is commonly referred to as ＂weight shift＂. Finally; after leaving the chair, the leg and trunk joints are straightened to achieve upright stance. The STS task can be considered of major importance for impaired and elderly people to achieve minimal mo- bility and independence. In this paper we detail a procedure for the design of assisting devices to be used for the STS. In par- ticular, an experimental procedure is described firstly to track and record point trajectories and the orientation of the trunk during the STS. This analysis is then used to get information for the design of assisting devices. A proposal and simulation results are presented for a novel mechatronic system. In particular, for the case under study experimental tests are used to drive the actua- tion system for the reported simulation. A functional mechatronic scheme is then proposed to control the device during its operation.     

The outlook for the development of live vaccines for the prevention of melioidosis

The effectiveness of immunization with Burkholderia pseudomallei attenuated strains (Pur and Ts), heterologous vaccines and the recombinant culture of Francisella tularensis RM2 carrying a plasmid with fragments of B. pseudomallei chromosome was studied in four species of experimental animals, essentially differing in their sensitivity to melioidosis. The most immunogenic B. pseudomallei mutants, introduced subcutaneously, created a statistically significant level of protection in animals, moderately sensitive to melioidosis, but proved to be ineffective in highly sensitive animal models when tested under the same conditions. In aerogenic infection the effectiveness of the experimental vaccines under study in all species of the animals was on the same level. The study showed good prospects of using tularemia vaccine for inducing heterologous immunity to melioidosis, as well as the possibility of its use as the basis of a bivalent gene-engineering vaccine.     

Perspectives for subunit vaccines for the control of ticks

For the first time, successful vaccination against a tick has been carried out using a single defined antigen. Further, it has been shown that it is feasible to produce active antigenic material by recombinant DNA technology. This represents a significant advance towards the development of an alternative means of tick control. Nevertheless, as with any new product and new technology, much developmental work still has to be done before one can be confident that a practical means of tick control will result. From the published information, it does not seem that research on vaccines against other tick species is as advanced as that on Boophilus microplus. The work on B. microplus may, however, provide a short cut to the development of further tick vaccines.     

Template for developing guidelines for the evaluation of the clinical efficacy of psychophysiological interventions

An essential function of both the Association for Applied Psychophysiology and Biofeedback (AAPB) and the Society for Neuronal Regulation (SNR) is the systematic evaluation of psychophysiological interventions that have been developed for the treatment of medical and psychiatric disorders. In order to address scientific concerns regarding the efficacy of specific clinical applications of biofeedback, these two societies formed and Efficacy Task Force. The process to be used in the assessment of treatment efficacy, specificity and clinical utility is presented in the form of a template that will serve as the foundation for a series of scientific reviews and practice guidlines to be published by both societies.     

Models for the morphogenesis of the molluscan shell

We give a review of current theories of morphogenesis of both the general coiling and the ornamentation of molluscan shells. These two aspects of shell growth are closely connected, as ornamentation is primarily due to local perturbations of the general apertural growth field controlling coiling. Also, a new, generalized, free-form apertural growth map model is presented in this paper, illustrating some aspects of the regulation of logarithmic spiral growth. This model is used to simulate the formation of megastriae in ammonoids. We emphasize the importance of damaged specimens and how they regenerated, as illustrated with examples from ammonoids. The phenomenon of ornamental compensation can be explained by a mechanism involving a pre-pattern in the mantle. However, simple reaction-diffusion models for ornamental pattern formation should be regarded only as useful abstractions.     

Molecular cloning of the cDNA for tissue factor, the cellular receptor for the initiation of the coagulation protease cascade

We have isolated cDNA clones encoding the complete sequence of the heavy chain of tissue factor (TF), the high-affinity receptor responsible for cellular initiation of the coagulation protease cascade. An 885 bp open reading frame encodes a 295 amino acid polypeptide including a leader sequence with alternative cleavage sites. A single 2.3 kb mRNA is identified, and Southern blotting is consistent with a single gene. The coding sequence defines a protein with features characteristic of an integral membrane protein. This receptor appears novel, lacking significant homology with other proteins; however, TF contains the uncommon tryptophan-lysine-serine (WKS) sequence repeated three times, a sequence we find in some serine protease-binding proteins and suggest may represent a functional sequence motif.     

A simple procedure for the preparation of lipopolysaccharide for the production of antisera

Lipopolysaccharide (LPS) was isolated from a strain of Escherichia coli O157 by two different methods and used to prepare antisera in rabbits. LPS prepared by the proteolytic digestion of whole cells was identical to LPS prepared with hot-phenol, as shown by SDS-PAGE and silver staining. Antisera from rabbits receiving these LPS preparations contained high titred antibodies (>10⁵) of the IgM class to E. coli O157 LPS.     

Strategies for the identification of loci responsible for the pathogenesis of multiple sclerosis

Multiple sclerosis (MS) is a chronic, debilitating disease, which manifests itself by de-myelination of the central nervous system (CNS). MS is predominantly found in Caucasians of European decent and is more prominent in females than males. MS is one of the most prevalent causes of disability of young adults in the world. The exact cause of MS is not known, however genetic susceptibility to MS is linked to the major histocompability complex (MHC). Self reactive CD4+ T cells, specific for CNS antigens, such as myelin basic protein (MBP), myelin oligodendrocyte glycoprotein (MOG) and proteolipid protein (PLP), are detectable in MS patients along with pathogenic autoantibodies specific to these CNS antigens produced by B cells. These observations suggest that MS is an autoimmune disease. Epidemiology of MS along with the analysis of sibling pairs and twins suggest that the multiple genetic factors and their interaction with environment contribute to disease susceptibility. Recent developments and advancements in genetic analysis may aid in accurate determination of genetic risk factors for the development of MS. We review these developments, advances in technology and discuss recent results in this article. These authors contributed equally to this paper     

Structural basis for the lower affinity of the insulin-like growth factors for the insulin receptor

Insulin and the insulin-like growth factors (IGFs) bind with high affinity to their cognate receptor and with lower affinity to the noncognate receptor. The major structural difference between insulin and the IGFs is that the IGFs are single chain polypeptides containing A-, B-, C-, and D-domains, whereas the insulin molecule contains separate A- and B-chains. The C-domain of IGF-I is critical for high affinity binding to the insulin-like growth factor I receptor, and lack of a C-domain largely explains the low affinity of insulin for the insulin-like growth factor I receptor. It is less clear why the IGFs have lower affinity for the insulin receptor. In this study, 24 insulin analogues and four IGF analogues were expressed and analyzed to explore the role of amino acid differences in the A- and B-domains between insulin and the IGFs in binding affinity for the insulin receptor. Using the information obtained from single substituted analogues, four multiple substituted analogues were produced. A "quadruple insulin" analogue ([Phe(A8), Ser(A10), Thr(B5), Gln(B16)]Ins) showed affinity as IGF-I for the insulin receptor, and a "sextuple insulin" analogue ([Phe(A8), Ser(A10), Thr(A18), Thr(B5), Thr(B14), Gln(B16)]Ins) showed an affinity close to that of IGF-II for the insulin receptor, whereas a "quadruple IGF-I" analogue ([His(4), Tyr(15), Thr(49), Ile(51)]IGF-I) and a "sextuple IGF-II" analogue ([His(7), Ala(16), Tyr(18), Thr(48), Ile(50), Asn(58)]IGF-II) showed affinities similar to that of insulin for the insulin receptor. The mitogenic potency of these analogues correlated well with the binding properties. Thus, a small number of A- and B-domain substitutions that map to the IGF surface equivalent to the classical binding surface of insulin weaken two hotspots that bind to the insulin receptor site 1.     

Program for the application of genetic transformation for crop improvement in the semi-arid tropics

Summary The semi-arid tropics are characterized by unpredictable weather, limited and erratic rainfall and nutrient-poor soils and suffer from a host of agricultural constraints Several diseases, insect pests and drought affect crop productivity. Developing stress-resistant crops has been a worthwhile activity of the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). Mandated crops of ICRISAT, including groundnut, pigeonpea, chickpea, sorghum and pearl millet, are the main staple foods for nearly one billion people in the semi-arid tropics. Genetic transformation provides a complementary means for the genetic betterment of the genome of these crops. Judicious application of biotechnological tools holds great potential for alleviating some of the major constraints to productivity of these crops in the agricultural systems of the semi arid tropics. This article reviews plant genetic engineering in relation to its applications in genetic enhancement and the improvement of important crops of the semi-arid tropics. For the benefit of nonbiotechnologists, a brief review of technical aspects of plant genetic engineering is also included.     

Pilot-scale process sensitivity studies for the scaleup of a fungal fermentation for the production of pneumocandins

The filamentous fungus Glarea lozoyensis produces a novel, pharmaceutically important pneumocandin (B(0)) that is used to synthesize a lipopeptide which demonstrates cidal activity against clinically relevant pathogens. A range of unwanted pneumocandin analogs are also produced by the organism. To maintain the unwanted impurities to acceptable levels upon scaleup, a good understanding of the impact of chemical and physical environment on the cell physiology is required, which benefits downstream processing. Pilot-scale studies were performed to determine the impact of dissolved oxygen, temperature, pH, and carbon dioxide on the process. Experiments included multiple fermenters (up to seven) at 0.07 and 0.8 m(3) scale using single source medium sterilization and inoculum. Gas blending was used to separate effects of dissolved oxygen from agitation. The process was significantly influenced by dissolved oxygen level. The critical dissolved oxygen tension (C(crit)) for growth was below 2% air saturation. The C(crit) for production of pneumocandin B(0) was 20% air saturation, with a significant reduction of the specific production rate below this value. In contrast, low dissolved oxygen levels produced a substantial increase of pneumocandins B(1), B(5), and E(0), while high dissolved oxygen levels produced a disproportionate increase of D(5). This sensivity to dissolved oxygen was independent of agitation within a power range of 2-15 kW/m(3). Broth viscosity was impacted below 10% dissolved oxygen, suggesting an effect on morphology. The process was shown to be sensitive to temperature but relatively insensitive to pH and carbon dioxide (in the exhaust gas) within the ranges studied. This scaledown analysis explained phenomena seen at pilot scale and helped define operating boundary conditions for successful scale up to 19 m(3).     

The case for the hybrid capital approach for the measurement of the welfare and sustainability

This paper provides an overview of the plethora of approaches that are available to measure welfare and sustainable development. Many methods exist but there is no consensus on the ‘correct’ approach. Furthermore, we also show that the wide variety of sustainable development indictor (SDI) sets which have been adopted also show significant differences. We argue that this is mostly because many of these studies do not use a theoretical approach. We argue that the ‘capital approach’, which is used in the sustainability debate, is the most promising method to enhance international harmonization. Support is mounting in the scientific, policy and statistical communities for this approach in which economic capital, human capital, natural capital and social capital are distinguished. Many applications of this method express these capital stocks in monetary units (the ‘monetary capital approach’). This paper argues that the ‘hybrid capital approach’, in which the capital stocks can also be measured in non-monetary units, is probably more likely to achieve consensus over a large number of countries and institutes. Also a number of challenges remain for the capital approach. We argue that ideally the indicators should be based on satellite accounts of the national accounting framework. Also the capital approach could be further expanded to current welfare, progress of societies, inequality, and the international dimension of sustainability. We conclude that if the hybrid capital approach is adopted it may become easier to make consistent, theoretically sound and policy relevant comparisons between countries.     

检验医学专业临床实习管理存在的问题及对策

临床实习是医学理论和临床实践工作有机结合的连接点,是医学生走向临床工作必不可少的重要环节。临床实习教学是医学生教育中一个重要的组成部分,是从课堂到临床、从理论到实践、从理性到感性的重要过程,也是巩固基础知识、理论联系实际、走向独立工作岗位的重要一步。在临床实践过程中,教职人员要培养学生获取、分析和处理疾病信息的能力,正确书写病历、熟练掌握诊疗技术以及与患者及家属和谐沟通的能力。医学检验学是运用现代物理化学方法、手段进行医学诊断的一门学科,通俗的说,就是利用仪器、试剂、CT扫描等检测人的各项指标是否正常,为临床诊断提供依据。因此,加强临床检验医学专业的实习管理工作至关重要。本文从建立合理的教学管理体系、加强临床实习考核制度、完善实习管理、加强教师队伍建设等几个方面,探讨临床检验学实习管理存在的问题,并提出相应的对策,为高等医学院校教学管理工作提供思路。     

Anatomical basis for the mobility of the esophagus: implications for catheter ablation of atrial fibrillation

We present autopsy data from a patient that illustrates the anatomical factors that allow the esophagus to be a mobile structure, especially with respect to the posterior left atrial wall.     

A model for the functioning of the striatum

A model is presented for the operation of the striatum. The model posits that the basal ganglia are responsible for driving smooth transitions of state for an organism. We propose that this is accomplished through the computation of a potential function within the striatum on which a gradient descent is performed toward the goal state. The model suggests that various somatotopic regions of the striatum correspond to state spaces, each of which pertains to a different aspect of the organism. This paper discusses this model only in the context of motor control, i.e., egomotion and limb movement. The model appears to account for a variety of experimental results, and for some unusual properties of the striatum.     

Technical Procedures for the Study of the Nucleolonema

In a recent paper¹ the authors have shown filamentous structures within the nucleolus of all cells. This structure was named the nucleolonema. In the present paper the technical procedures which prove their existence are described in detail.

There are two groups: a) Silver impregnation procedures and iron-pyrogallic stain for fixed material; b) phase contrast microscopy, dark-field illumination and oblique transillumination for fresh material.

The suitable objects are mentioned in every case in order to obtain the best results.     

What's good for the host is good for the bug

Tuberculosis, caused by Mycobacterium tuberculosis, kills approximately two million people each year. The infection is characterized by an inflammatory response culminating in the formation of a granuloma, a collection of immune cells that controls the infection. However, the granuloma can be the source of immunopathology that encourages transmission. Recent data support the idea that mycobacterial products can positively and negatively regulate the inflammatory response. Our contention is that induction of the immune response and subsequent granuloma formation is beneficial to the host for control of infection, and is also beneficial to the bacillus, as a place to hide and as a means for transmitting the infection to naive hosts.     

Semiautomatic regulator for the preparation of microelectrodes for electrophysiology

This paper describes an electronic device for making metallic microelectrodes to be used for electrophysiological experiments. These microelectrodes are endowed with a small tissue-electrode capacity and a high mechanical strength. The same microelectrodes are applicable for derivation of spikes as in the case of microstimulation of nervous structures during repeated penetrations.