The fact that none of the known DNA polymerases is able to initiate DNA chains but only to elongate from a free 3' -OH group raises the problem of how replication is initiated, both at the replication origin and on Okazaki frag- ments. It was first shown by A. KORNBERG et al. that a general mechanism to initiate replication is through the formation of an RNA primer catalyzed by RNA polymerases or by a new class of enzymes, the primases (KORNBERG 1980). This mechanism, which can be used in the case of circular DNA molecules or linear DNAs that circularize or form concatemers, cannot be used at...
The fact that none of the known DNA polymerases is able to initiate DNA chains but only to elongate from a free 3' -OH group raises the problem of how...
Intracellular pathogens are responsible for a number of important diseases worldwide, including tuberculosis, plague and bacillary dysentery. This volume focusses on those intracellular pathogens that have been studied most extensively at the molecular, genetic, and cellular level. The reviews attempt to integrate the information derived from these diverse approaches into a cohesive picture. In recent years the entry steps have been described at the molecular and genetic level, and the important signal transduction events are being elucidated. It is now becoming clear that there are both...
Intracellular pathogens are responsible for a number of important diseases worldwide, including tuberculosis, plague and bacillary dysentery. This vol...
It has been 12 years since the first proposal was made to sub- divide mouse CD4 I T cell clones into Th I and Th2 subsets, based on their differences in cytokine production, and 7 years since the first clear demonstration of a similar dichotomy among human T cell clones. In the ensuing period, it has been realized that inappropriate development of Th I or Th2 responses are important features of many immunological and infectious dis- eases. Perhaps the first group of diseases to be understood in terms of preferential Th subset activation were allergic diseases (see PARRONC'HI et aI. , this...
It has been 12 years since the first proposal was made to sub- divide mouse CD4 I T cell clones into Th I and Th2 subsets, based on their differences ...
Most diseases are multifactoral. Transgenic technology permits gene(s) of interest to be expressed in a small manipulatable laboratory animal model. By this process, murine models of human infections can be developed and studied; effects of cytokines in vivo, focally expressed in unique cells can be established and manipulated, and a variety of autoimmune disorders, mimicking human disease can be constructed. In this volume, these approaches for study of human immunodeficiency virus, hepatitis virus, viruses causing tumors and chronic degenerative disorders are described. Also included are...
Most diseases are multifactoral. Transgenic technology permits gene(s) of interest to be expressed in a small manipulatable laboratory animal model. B...
Pore-forming toxins are virulence factors produced by a great variety of pathogenic bacteria ranging from the Gram-positive Staphylococcus aureus to the Gram-negative Helicobacter pylory. The recent studies reviewed in this volume describe the progress that has been made in dissecting the different steps of the mode of action of these proteins which generally include binding to specific cell surface receptors, oligomerization into ring like structures and membrane perforation.
Pore-forming toxins are virulence factors produced by a great variety of pathogenic bacteria ranging from the Gram-positive Staphylococcus aureus to t...
TOR, the Target of Rapamycin was discovered a little over ten years ago in a genetic screen in S. cerevisiae in search of mutants resistant to the cytostatic effects of the antimycotic, rapamycin. Recent studies have placed TOR at the interface between nutrient sensing and the regulation of major anbolic and catabolic responses. The editors have gathered the leading figures in the field of TOR and its role in cellular homeostasis and human diseases.
TOR, the Target of Rapamycin was discovered a little over ten years ago in a genetic screen in S. cerevisiae in search of mutants res...
Viruses are studied either because they cause significant human, animal or plant disease or because they are useful materials for probing basic phenomena in biology, chemistry, genetics and/or molecular biology. Arenaviruses are unusually interesting in that they occupy both categories. Arenaviruses cause several human diseases known primarily as the hemorrhagic fevers occurring in South and Latin America (Bolivia: Machupo, Argentine, Junin virus, and Brazil: Sabia virus) and in Africa (Lassa fever virus). Because such viruses produce profound disabilities and often kill the persons they...
Viruses are studied either because they cause significant human, animal or plant disease or because they are useful materials for probing basic phenom...
It has been clear for a long time that after transplantation of a lymphoid organ, hematopoietic stem cells can regenerate the compartments of the organ, provided that the rest of its architecture - the strome, the epithelia and the vessels - is intact. Ahead lies the even greater challenge to assemble also these other architectural elements of a lymphoid organ by transplanting stem cells. The workshop on lymphoid organogenesis was convened to review current knowledge of and experimental skills involved in this grand project to build a lymphoid organ from its individual cellular components.
It has been clear for a long time that after transplantation of a lymphoid organ, hematopoietic stem cells can regenerate the compartments of the orga...
An estimated 2-3 billion people in the less developed countries suffer from infections, often multiple, caused by a variety of parasitic organisms. These infections are frequently debilitat- ing rather than fatal, and the toll in human misery is fearsome. To this may be added the prevalence of similar diseases in do- mestic animals, which diminish supplies of animal pro tein. As the world population increases, the already enormous problem also continues to grow. The resources of the less developed nations are inadequate for solving the problem, and in the de- veloped countries a lack of...
An estimated 2-3 billion people in the less developed countries suffer from infections, often multiple, caused by a variety of parasitic organisms. Th...
The development of innovative molecular techniques such as pulse-field gel electro- phoresis, cDNA subtraction libraries and chromosome hopping libraries coupled with the increasing popularity in the prospect of sequencing mammalian genomes, has triggered a resurgence of interest in finding and characterizing genes that playa role in modifying immune processes and diseases. Genetically defined strains of mice (e. g., inbred strains and recently derived stocks of wild mice) provide ideal models for examining the genetic control of diseases as a result of their syntenic relationship with man in...
The development of innovative molecular techniques such as pulse-field gel electro- phoresis, cDNA subtraction libraries and chromosome hopping librar...