ISSN:0892-6638    

DOI:10.1096/fasebj.5.3.2001785

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

The sixth symposium in the series “Contemporary Topics in Immunology” was held in New Orleans on June 3, 1990, at the joint meeting of The American Association of Immunologists and the American Society of Biochemistry and Molecular Biology. The symposium was sponsored jointly by The American Association of Immunologists, the Clinical Immunology Society, and and the National Institute of Allergy and Infectious Diseases, and was titled “The Contributions of Basic Immunology to Human Health.” Five speakers, whose research has clear relevance to the treatment and prevention of major human diseases, discussed topics of great current interest: hematopoietic stem cells, cell adhesion and lymphocyte homing; the complexities of autoimmunity and approaches to diverting or depressing autoaggressive immunity; structure and functions of the interferons and the construction of designer and chimeric interferons; the varied functions of transforming growth factors and molecular events that regulate the synthesis of TGFβ; and the roles of cytokines in the expression of human immunodeficiency virus and the prospects for controlling HIV infections by regulating selected cytokines. This symposium will be remembered for the exceptional clarity with which each speaker illustrated how fundamental knowledge in immunology fuels advances in the treatment and prevention of those human disorders that involve the immune system.—Albright, J. F.; Oppenheim, J. J. Contributions of basic immunology to human health.FASEB J.5: 265–270; 1991.

ISSN:0892-6638    

DOI:10.1096/fasebj.5.3.1705905

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

In mammals, liver perisinusoidal stellate cells play an important role as a main store of body retinol (vitamin A). This fat‐soluble vitamin is essential for vision, and regulates differentiation and growth of many cell types during embryonal development as well as in adult tissues. Thus, many cell types require a continuous supply of retinol. The storage of retinol (as retinyl esters) in stellate cells ascertains ample access of retinol to such cells also during periods with a low dietary intake. In lower vertebrates such as fish, vitamin A‐storing stellate cells are found not only in the hepatic lobule, but also in the connective tissues of organs like intestine, kidney, ovaries, testes, and gills. Extrahepatic vitamin A‐storing stellate cells are found in higher vertebrates when excessive doses of vitamin A are administered. It is not clear at present whether these cells also play a role in retinol metabolism under normal conditions. Stellate cells proliferate in a fibrotic liver, and they have been found to synthesize connective tissue compounds such as collagen. It was recently demonstrated that stellate cells are the principal cellular source of collagen and other extracellular substances in normal as well as fibrotic livers. Therefore, stellate cells, which seem to be a specialized type of pericyte, have a central role in the pathological changes observed during the development of liver fibrosis.—Blomhoff, R.; Wake, K. Perisinusoidal stellate cells of the liver: important roles in retinol metabolism and fibrosis.FASEB J.5: 271–277; 1991.

ISSN:0892-6638    

DOI:10.1096/fasebj.5.3.2001786

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

The problem of the etiology of Alzheimer's disease has not been solved. But in the past several years there have been significant extensions of our knowledge of the disease and advances in determining the molecular changes underlying the disorder. There is now convincing evidence that the dementia per se is caused by loss of neurons and synapses, particularly in neocortex and hippocampus. The molecular aspects of amyloid and its precursor protein have been defined. The nature of intracellular changes leading to accumulation of the paired helical filament is beginning to be understood. For the first time, putative risk factors can be described in terms of pathogenetic mechanisms. Thus, it may become possible in the not‐too‐distant future to discover interventions that will slow the progress of this devastating disease.—Katzman, R.; Saitoh, T. Advances in Alzheimer's disease.FASEB J.5: 278–286; 1991.

ISSN:0892-6638    

DOI:10.1096/fasebj.5.3.2001787

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

It is now possible to culture cells from most organs of the body under conditions in which they continue to express at least some of their differentiated traits, and to model some of the differentiation processes that occur during embryonic and adult life. How much can these cultures tell us about the acquisition and maintenance of the differentiated state? To answer this question I shall outline the features of several cell culture models, dividing them into categories according to whether they mimic differentiation during development, differentiation of adult stem cell progeny, or the transition from one differentiated phenotype to another. In spite of the diversity of cell types under consideration, it is possible to detect some common themes: the stability of the differentiated state; the relationship between proliferation and differentiation; the relative importance of intrinsic cellular programming and environmental regulation; and possible mechanisms for transcriptional control of the genes that are activated during differentiation. In recent years cell culture models have yielded a great deal of information about differentiation and the way is now clear for even more exciting discoveries.—Watt, F. M. Cell culture models of differentiation.FASEB J.5: 287–294; 1991.

ISSN:0892-6638    

DOI:10.1096/fasebj.5.3.2001788

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

Hypochlorite is a reactive oxidant formed as an end product of the respiratory burst in activated neutrophils. It is responsible for killing bacteria and has been implicated in neutrophil‐mediated tissue injury associated with the inflammatory process. Although hypochlorite is a potent cytotoxic agent, the primary mechanism by which it exerts its effect is unclear. This review examines evidence that the primary event in hypochlorite cytotoxicity is the loss of adenine nucleotides from the target cell. This loss appears to be mediated by the formation of adenine nucleotide chloramines which are reactive intermediates with a free radical character and are capable of forming stable ligands with proteins and nucleic acids.—Bernofsky, C. Nucleotide chloramines and neutrophil‐mediated cytotoxicity.FASEB J.5: 295–300; 1991.

ISSN:0892-6638    

DOI:10.1096/fasebj.5.3.1848195

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

Saposins are sphingolipid activator proteins, four of which are derived from a single precursor, prosaposin, by proteolytic processing. These small heat‐stable glycoproteins (12–14 kDa) are required for the lysosomal hydrolysis of a variety of sphingolipids. Characterization of these four activator proteins, two of which were recently discovered, and their importance in human health and disease are reviewed in this article.—O'Brien, J. S.; Kishimoto, Y. Saposin proteins: structure, function, and role in human lysosomal storage disorders.FASEB J. 5: 301–308; 1991.

ISSN:0892-6638    

DOI:10.1096/fasebj.5.3.2001789

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

The cell‐type‐specific expression of many genes is determined at the level of transcription. Transcription factors, acting at promoter and enhancer elements, are involved in the control of this process. To understand the basis of this regulation it has become important to analyze the control of transcription factors themselves. A variety of transcriptional, translations, and posttranslational mechanisms have been described, and are discussed in this review article.—Falvey, E.; Schibler, U. How are the regulators regulated?FASEB J.5: 309–314; 1991.

ISSN:0892-6638    

DOI:10.1096/fasebj.5.3.2001790

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

Because receptors, G proteins, and phospholipases all exist within a membrane lipid environment, it is not unreasonable to assume that an enzyme capable of changing the lipid environment can affect the coupling relationship among these signal transducing components. Our previous study showed that a muscarinic acetylcholine receptor regulates phosphatidylcholine phospholipase D via a G protein in brain. We demonstrate here that phosphatidylinositol phospholipase C and phosphatidylcholine phospholipase D are simultaneously activated within 15 s by muscarine in the presence of 1 μM GTPγS. More important, inhibition of phospholipase D by zinc attenuated carbamylcholine‐induced activation of phospholipase C by 30%. Our additional evidence strongly indicates that the receptor‐regulated phospholipase D plays an important modulatory role in agonist‐stimulated phosphatidylinositol breakdown. This modulatory effect may be achieved by changing the membrane microenvironment in which phospholipase C and phosphoinositol lipids reside, consequently amplifying the inositol phospholipid signaling process. Our results lead us to postulate that the potential interaction between two different signaling pathways may provide a cell with intracellular coordination and enable the cell to achieve functional responses.—Qian, Z.; Drewes, L. R. Crosstalk between receptor‐regulated phospholipase D and phospholipase C in brain.FASEB J.5: 315–319; 1991.

ISSN:0892-6638    

DOI:10.1096/fasebj.5.3.2001791

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

Retinoids induce the promyelocytic cell line, HL‐60, to differentiate along the granulocytic pathway in vitro. A number of water‐soluble and nitrogen‐containing retinoids were synthesized in our laboratory [retinoyl‐glucose (RAGL), retinyl‐glucose (ROGL), retinoyl‐adenosine (RADS), retinoyl‐adenine (RAD), retinoyl‐β‐glucuronide (βRAG), and retinoyl‐α‐glucuronide (αRAG)]. These retinoids (10–5to 10–8M), as well as retinoic acid (RA) and retinol (ROL), were tested for their ability to induce the differentiation of HL‐60 cells in vitro and to affect cell growth and viability during a 24‐ to 72‐h incubation period. Differentiation was assessed by measuring the percentage of cells expressing the Mac‐1 antigen on their cell surfaces. RA and the conjugates of RA were all quite active in inducing HL‐60 cell differentiation, whereas ROL and ROGL had much less activity at equimolar concentrations.βRAG, αRAG, RADS, and RAD were less toxic, whereas the glucose conjugates of retinol and retinoic acid (ROGL and RAGL) were both considerably more toxic than either RA or ROL at equimolar concentrations. All retinoids affected cell growth in a dose‐dependent fashion. At 24 h, free RA or ROL was not detected in the cells after incubation with any of the retinoid conjugates.—Janick‐Buckner, D.; Barua, A. B.; Olson, J. A. Induction of HL‐60 cell differentiation by water‐soluble and nitrogen‐containing conjugates of retinoic acid and retinol.FASEB J.5: 320–325; 1991.

ISSN:0892-6638    

DOI:10.1096/fasebj.5.3.2001792

出版商:Wiley    

年代:1991

数据来源: WILEY