Home About us Contact
|
Home About us Contact | ||
|
|
||
Classical Concepts (classical + concept)
Selected AbstractsInterleukin-21 triggers both cellular and humoral immune responses leading to therapeutic antitumor effects against head and neck squamous cell carcinomaTHE JOURNAL OF GENE MEDICINE, Issue 1 2006Hiroshi Nakano Abstract Background Interleukin-21 (IL-21) plays important roles in the regulation of T, B, and natural killer (NK) cells. We hypothesized that the cytokine may provide a novel immunotherapy strategy for cancer by stimulating both Th1 and Th2 immune responses. In this context, antitumor immunity induced by IL-21 was examined in mice bearing subcutaneous head and neck squamous cell carcinomas (HNSCC). Methods A plasmid vector encoding murine IL-21 was injected intravenously into mice with pre-established HNSCC tumors, either alone or in combination with a vector construct expressing IL-15. Cytotoxic T lymphocyte (CTL) and NK killing activities were evaluated by chrome release assays, while HNSCC-specific antibody was examined by flow cytometry and ELISA. Results Significant antitumor effects were obtained by repeated transfection with either the IL-21 or the IL-15 gene. Co-administration of both cytokine genes resulted in increased suppression of tumor growth, significantly prolonging the survival periods of the animals. Thirty percent of the tumor-bearing mice that received the combination therapy survived for more than 300 days, completely rejecting rechallenge with the tumor at a distant site. IL-21 induced significant elevation of HNSCC-specific CTL activity, while IL-21 and IL-15 augmented NK activity in an additive manner. IL-21 gene transfer also promoted the production of tumor-specific IgG. Conclusions In vivo transduction of the IL-21 gene elicits powerful antitumor immunity, including both humoral and cellular arms of the immune response, and results in significant suppression of pre-established HNSCC. Co-transfer of the IL-15 gene further improved the therapeutic outcome, mainly by augmenting NK tumoricidal activity. The biological effects of IL-21 may be in sharp contrast to those of conventional Th1 and Th2 cytokines, suggesting intriguing implications of this cytokine for the classical concept of Th1 vs. Th2 paradigm. Copyright © 2005 John Wiley & Sons, Ltd. [source] Normal and abnormal fetal cardiac anatomyPRENATAL DIAGNOSIS, Issue 13 2004Andrew C. Cook Abstract The heart is often perceived as a difficult organ to understand by ultrasound during fetal life. This is undoubtedly reflected in the low detection rate of cardiac abnormalities as compared to those of most other organ systems in the fetus. In this article we start by updating classical concepts of cardiac embryology, many of which were previously difficult to understand since they were overly simplistic or purely observational. We then lead on to the structure and growth of the fully formed fetal heart where we review the anatomy and ultrasound appearances in detail and provide comparisons with major abnormalities. We emphasise the fact that a solid understanding of cardiac anatomy can enable those involved in fetal medicine to make full use of the views of the heart that are obtained by ultrasound and which are often only transient. Copyright © 2004 John Wiley & Sons, Ltd. [source] Determination of Intrinsic Minimum Bubbling Velocity in Fine Powder Aerations Based on Experimentally Measured Elastic Deformation CoefficientsTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2005Wiratni Wiratni Abstract It is found that the minimum bubbling velocity of aerated fine powder can be defined by experimentally measuring incremental elastic deformation coefficient (Y). The value of Y starts changing at a certain degree of powder expansion. The sudden change of Y indicates the initiation of the fractures in the homogeneously aerated expanded (HAE) emulsion phase. The intrinsic minimum gas velocity (Umb*), which causes this fracture initiation, can be significantly smaller than the so-called minimum bubbling velocity (Umb) defined by the classical concepts. On a trouvé que la vitesse d'ébullition minimum de fine poudre aérée peut se définir en mesurant expérimentalement le coefficient de déformation élastique incrémentiel (Y). La valeur de Y commence à changer à un certain degré d'expansion de la poudre. Le changement soudain de Y indique le départ de fractures dans la phase d'émulsion expansée et aérée de manière homogène (HAE). La vitesse de gaz minimum intrinsèque (Umb*), qui cause ce début de fractures, peut être significativement plus petite que la prétendue vitesse d'ébullition minimum (Umb) définie par les concepts traditionnels. [source] REVIEW ARTICLE: The Immune System in Pregnancy: A Unique ComplexityAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 6 2010Gil Mor Citation Mor G, Cardenas I. The immune system in pregnancy: a unique complexity. Am J Reprod Immunol 2010 Abstract Placental immune response and its tropism for specific viruses and pathogens affect the outcome of the pregnant woman's susceptibility to and severity of certain infectious diseases. The generalization of pregnancy as a condition of immune suppression or increased risk is misleading and prevents the determination of adequate guidelines for treating pregnant women during pandemics. There is a need to evaluate the interaction of each specific pathogen with the fetal/placental unit and its responses to design the adequate prophylaxis or therapy. The complexity of the immunology of pregnancy and the focus, for many years, on the concept of immunology of pregnancy as an organ transplantation have complicated the field and delayed the development of new guidelines with clinical implications that could help to answer these and other relevant questions. Our challenge as scientists and clinicians interested in the field of reproductive immunology is to evaluate many of the ,classical concepts' to define new approaches for a better understanding of the immunology of pregnancy that will benefit mothers and fetuses in different clinical scenarios. [source] | ||||||||||