摘要:

Bypass vein graft disease remains a significant limitation to the care of millions of patients with ischemic disease of the heart and lower extremities. The pathogenesis of this rapid, aggressive, occlusive disease lies in the remodeling response of the grafts themselves to the new arterial environment. As such, the molecular and cellular biology of neointimal hyperplasia provides a unique opportunity for cardiovascular researchers to more closely model a human clinical entity from its inception to the development of advanced disease. Recent years have therefore seen a broad new array of possible interventions for vein graft disease based on a sophisticated translation of genetic and molecular science. One of these applications, E2F decoys, has already progressed to phase III clinical studies, and many others will likely follow as the tools for therapeutic translation continue to improve. These include both gene transfer and gene blockade strategies.

ISSN:1173-8804    

出版商:ADIS    

年代:2004

数据来源: ADIS

摘要:

Mortality due to severe bacterial infections has not been markedly effected by the introduction of new antimicrobial drugs over the last 30–40 years. This has emphasized the need for development of new therapeutic strategies to combat sepsis. The outcome of an infection depends on two factors: the growth of the microorganisms (including the effect of antibacterial drugs), and the host’s defensive response to the invading organism. It is known that injection of bacterial products into experimental animals leads to enhanced nonspecific resistance to a variety of microorganisms. The discovery of the specific mediators responsible for modulation of host defense has created new possibilities for the development of alternative treatment strategies. Molecules such as interleukins, interferons, tumor necrosis factors and hematopoietic growth factors have become available in recombinant form, and their therapeutic potential in various infectious diseases has been tested in various experimental models of infections. Initial data in various patient groups indicate that adjunctive therapy with recombinant proinflammatory cytokines may have beneficial effects in the treatment of bacterial and fungal infections.

ISSN:1173-8804    

出版商:ADIS    

年代:2004

数据来源: ADIS

摘要:

Osteoarthritis (OA) is a debilitating, progressive disease of diarthrodial joints associated with the aging process. With the exception of anti-inflammatory corticosteroids and nonsteroidal anti-inflammatory drugs which inhibit cyclo-oxygenase-2, the enzyme responsible for prostaglandin biosynthesis in inflammation, no specific therapy based on fundamental intracellular pathways of chondrocytes and synoviocytes exists for the medical management of OA. At the molecular level, OA is characterized by an imbalance between chondrocyte anabolism and catabolism. Disruption of chondrocyte homeostasis primarily affects the cartilage extracellular matrix (ECM), which is responsible for the biomechanical properties of the tissue. Recent evidence has implicated cytokines, among which interleukin (IL)-1, tumor necrosis factor-α, IL-6, and IL-17 seem most involved in the OA process of cartilage destruction. The primary role of these cytokines is to modulate the expression of matrix metalloproteinases and cartilage ECM proteins. Cartilage repair that could restore the functional integrity of the joint is also impaired because chondrocytes in OA cartilage appear unable to respond to insulin-like growth factor-1 or respond abnormally to transforming growth factor-β. As these growth factors also modulate cytokine expression, they may prove useful in designing strategies for suppressing ‘chondrocyte activation’. Although cytokines and growth factors provide a potential therapeutic target for OA, it will be necessary to elucidate the fundamental mechanisms that cytokines employ to cause chondrocyte and synoviocyte dysfunction before ‘anti-cytokine’ therapy can be employed in the medical management of the disease.

ISSN:1173-8804    

出版商:ADIS    

年代:2004

数据来源: ADIS

摘要:

With the advent of functional genomics and the shift of interest towards sequence-based therapeutics, the past decades have witnessed intense research efforts on nucleic acid-mediated gene regulation technologies. Today, RNA interference is emerging as a groundbreaking discovery, holding promise for development of genetic modulators of unprecedented potency.Twenty-five years after the discovery of antisense RNA and ribozymes, gene control therapeutics are still facing developmental difficulties, with only one US FDA-approved antisense drug currently available in the clinic. Limited predictability of target site selection models is recognized as one major stumbling block that is shared by all of the so-called complementary technologies, slowing the progress towards a commercial product.Currently employedin vitrosystems for target site selection include RNAse H-based mapping, antisense oligonucleotide microarrays, and functional screening approaches using libraries of catalysts with randomized target-binding arms to identify optimal ribozyme/DNAzyme cleavage sites. Individually, each strategy has its drawbacks from a drug development perspective. Utilization of message-modulating sequences as therapeutic agents requires that their action on a given target transcript meets criteria of potency and selectivity in the natural physiological environment. In addition to sequence-dependent characteristics, other factors will influence annealing reactions and duplex stability, as well as nucleic acid-mediated catalysis. Parallel consideration of physiological selection systems thus appears essential for screening for nucleic acid compounds proposed for therapeutic applications. Cellular message-targeting studies face issues relating to efficient nucleic acid delivery and appropriate analysis of response. For reliability and simplicity, prokaryotic systems can provide a rapid and cost-effective means of studying message targeting under pseudo-cellular conditions, but such approaches also have limitations.To streamline nucleic acid drug discovery, we propose a multi-model strategy integrating high-throughput-adapted bacterial screening, followed by reporter-based and/or natural cellular models and potentially alsoin vitroassays for characterization of the most promising candidate sequences, before finalin vivotesting.

ISSN:1173-8804    

出版商:ADIS    

年代:2004

数据来源: ADIS

摘要:

The new generation of biological products are largely the result of genetic engineering. The qualitative and quantitative demand for recombinant proteins is steadily increasing. Molecular biologists are constantly challenged by the need to improve and optimise the existing expression systems, and also develop novel approaches to face the demands of producing the complex proteins of tomorrow. This continuous evolution is paralleled by growing concerns about the safety of these novel pharmaceuticals, with health authorities setting high standards for certification. One of the strategies used by researchers in this field involves sourcing new genetic elements for incorporation into expression systems by systematically analysing the rich natural diversity of microorganisms and plant-based expression systems. There are, in addition, numerous tools for modifying microorganisms and for re-engineering existing biological pathways or processes to meet the needs of the pharmaceutical industry. The aim of this review is to present the conventional and alternative expression systems, focusing on prokaryotic expression systems and briefly exploring other complementary recombinant protein production systems and their unique features.

ISSN:1173-8804    

出版商:ADIS    

年代:2004

数据来源: ADIS

摘要:

BackgroundHepatitis C virus (HCV) may be associated with a variety of autoimmune phenomena causing a therapeutic dilemma for treatment with interferon-α (IFNα), which stimulates autoimmune symptoms, or with corticosteroids, which may lead to an increasing of viral load. To evaluate the possible role of intravenous immunoglobulins (IVIg) in the response of patients treated with IFNα, we administered IVIg plus IFNα and compared the results with a group of patients treated with IFNα alone.Complete biochemical response was defined as a sustained normalisation of alanine aminotransferase levels, and complete virological response was defined as complete clearance of virus throughout the entire 6-month follow-up period. Immunological response was measured in terms of Autoimmune Hepatitis (AIH) score, while histological response was based on a reduction in histological activity index (HAI) score.MethodsForty-two patients affected by chronic hepatitis C with probable autoimmune disease were eligible for this open-label, randomised study. All patients tested positively for anti-nuclear antibodies, anti-smooth muscle antibodies, anti-liver/kidney microsomal antibodies and anti-mitochondrial antibodies. Patients were randomly assigned to one of two groups: group A received IVIg at a dosage of 400 mg/kg each day for 5 days, and then 3 MUI of leucocyte IFNα three times a week, while group B received physiological solution followed by the administration of leucocyte IFNα three times a week at the same dosage for 6 months.Complete biochemical response was defined as a sustained normalisation of alanine aminotransferase levels, and complete virological response was defined as complete clearance of virus throughout the entire 6-month follow-up period. Immunological response was measured in terms of Autoimmune Hepatitis (AIH) score, while histological response was based on a reduction in histological activity index (HAI) score.ResultsCompared with patients receiving IFNα alone, a higher percentage of patients who received IFNα plus IVIg showed complete virological and histological responses (p = 0.04). More patients in the combination therapy group achieved biochemical and immunological responses, although the differences between the groups were not statistically significant at all time points.ConclusionsExogenously added Ig might modulate the immune network at various points. We propose that the immunomodulating action of IVIg acts synergistically with IFNα, achieving a better response to IFN treatment in patients with chronic HCV associated with autoimmunity. Data obtained from this preliminary study indicate a positive prospective for the clinical use of gamma globulins in patients with a high probability of autoimmune disorders associated with HCV infection.

ISSN:1173-8804    

出版商:ADIS    

年代:2004

数据来源: ADIS