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Sippel AE, Schäfer G, Faust N, Saueressig H, Hecht A, Bonifer C. Chromatin domains constitute regulatory units for the control of eukaryotic genes. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 1993; 58:37-44. [PMID: 7956050 DOI: 10.1101/sqb.1993.058.01.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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52
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Thompson JS, Hecht A, Grunstein M. Histones and the regulation of heterochromatin in yeast. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 1993; 58:247-56. [PMID: 7956035 DOI: 10.1101/sqb.1993.058.01.029] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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53
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Hecht A. [Pathogenesis of gastroduodenal ulcer]. Dtsch Med Wochenschr 1992; 117:1941. [PMID: 1459029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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54
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Hecht A, Weide M. [Classification of causes of death in humans]. ZENTRALBLATT FUR PATHOLOGIE 1992; 138:367-72. [PMID: 1477086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The cause of death of 2631 deceased persons (2418 adults, 213 children) was determined. Classification is proposed by monocausative, relatively monocausative, competitive and complex causes of death. This classification would be in accordance with types of dying, as suggested by Thieke and Nizze [17]. A comparison of results has revealed far-reaching agreement between the two principles of classification with regard to frequency distribution of causes, except for the category of complex causes which, however, was of minor importance in our investigations. This was attributed to the fact that classification was facilitated by consideration of epistemological approaches. Differences among categories of causes were attributable also to age and sex of the cases studied, both adults and children.
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Steinfath M, von der Leyen H, Hecht A, Neumann KH, Schmitz W, Scholz H, Haverich A, Heublein B. Decrease in beta 1- and increase in beta 2-adrenoceptors in long-term follow-up after orthotopic cardiac transplantation. J Mol Cell Cardiol 1992; 24:1189-98. [PMID: 1336061 DOI: 10.1016/0022-2828(92)93182-j] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Total beta 1- and beta 2- subtype distribution were examined in right ventricular biopsies taken from 100 patients 1-60 months after orthotopic cardiac transplantation and from eight prospective transplant donor hearts serving as controls. The patients were classified into eight groups depending on the time after transplantation that the biopsies were taken: 1-3 (n = 15), 4-7 (n = 15), 8-11 (n = 6), 12 (n = 15), 24 (n = 15), 36 (n = 12), 48 (n = 12) and 60 months (n = 10). The non-selective beta-adrenoceptor antagonist (-)-[125I]-iodocyanopindolol (ICYP) was used as a radioligand to assess total beta-adrenoceptor density. The beta 1- and beta 2-subtype distribution was determined with a beta 1-adrenoceptor saturating concentration of the selective beta 1-adrenoceptor antagonist CGP 20712A (300 nmol/l). In transplant donor hearts the total beta-adrenoceptor density was found to be 70.8 +/- 7.1 fmol/mg protein including a beta 1:beta 2-adrenoceptor ratio of about 80:20%. Until 36 months after cardiac transplantation the total number of beta-adrenoceptors showed no significant change. A slight but insignificant decrease was observed after 48 (16.2%) and 60 (21.2%) months. In contrast, from 12 to 60 months after cardiac transplantation the beta 1:beta 2-adrenoceptor ratio was shifted significantly (66:33% to 61:39%) as compared with transplant donor hearts which was due to an increase in beta 2- and a decrease in beta 1-adrenoceptor number. Thus, the surgically denervated, transplanted human heart exhibits a beta 2-adrenoceptor up-regulation during long-term follow-up. It is suggested that this up-regulation of the beta 2-adrenoceptor subtype could be owing to an increased importance of circulating catecholamines in modulating positive chronotropic and inotropic effects.
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56
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von der Leyen H, Steinfath M, Hecht A, Schmitz W, Scholz H, Neumann K, Haverich A, Heublein B. Changes in cardiac beta 1- and beta 2-adrenoceptor densities after human cardiac transplantation: relation to transplant coronary vasculopathy and pretransplantation disease. Am Heart J 1992; 124:686-93. [PMID: 1325108 DOI: 10.1016/0002-8703(92)90279-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In 100 patients 12 to 60 months after cardiac transplantation, the influence of transplant coronary vasculopathy and of the pretransplantation disease (end-stage heart failure caused by coronary artery disease or dilated cardiomyopathy) on the beta-adrenergic receptor (AR) numbers and beta 1/beta 2-AR ratio of right ventricular biopsies was determined. Patients with coronary vasculopathy (CVP) after cardiac transplantation had lower absolute numbers of beta 1-AR compared with patients without CVP. Since patients with CVP had increased left ventricular (LV) end-diastolic pressure and LV muscle mass, it is suggested that decreased beta 1-AR may be the result of an altered hemodynamic situation of the transplanted heart after development of CVP. Patients with dilated cardiomyopathy (DCM) before cardiac transplantation showed a decrease in total beta-AR and of the beta 1/beta 2-AR ratio as a result of an increase in beta 2-AR and a decrease in beta 1-AR numbers. The decreased beta 1/beta 2-AR ratio in patients with previous DCM may indicate that the beta-AR system of the transplanted heart might be influenced (at least in part) by pathophysiologic factors that are characteristic of the pretransplantation disease ultimately leading to cardiac transplantation and persisting after cardiac transplantation.
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57
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Heinke G, Hecht A, Heuser A. Betriebsbegleitende Qualitätssicherung von Chemieapparaten. CHEM-ING-TECH 1992. [DOI: 10.1002/cite.330640921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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58
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Grewal T, Theisen M, Borgmeyer U, Grussenmeyer T, Rupp RA, Stief A, Qian F, Hecht A, Sippel AE. The -6.1-kilobase chicken lysozyme enhancer is a multifactorial complex containing several cell-type-specific elements. Mol Cell Biol 1992; 12:2339-50. [PMID: 1569954 PMCID: PMC364406 DOI: 10.1128/mcb.12.5.2339-2350.1992] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
In the chromatin domain of the chicken lysozyme gene of myeloid and oviduct cells, which both have the potential to activate the gene, a developmentally stable DNase I-hypersensitive site is formed around 6.1 kb upstream of the gene. This implies that this DNA region, which has previously been demonstrated to function as a transcriptional enhancer element in myeloid cells, is intimately involved in the cell-type-specific activation of the lysozyme gene locus. Deletion analysis identifies a 157-bp minimal fragment that confers the same promacrophage-specific enhancer activity as the originally described 562-bp -6.1-kb enhancer fragment. By introducing specific point mutations, we demonstrate in transient gene transfer experiments that the minimal fragment consists of at least six adjacent elements, each substantially contributing to enhancer function. The compact multifactorial enhancer complex includes a nuclear factor I (NF-I)/TGGCA binding site, homologies to AP1, and octanucleotide or enhancer core consensus motifs. Point mutation of the NF-I binding site results in the loss of NF-I binding in vitro and enhancer activity in vivo after gene transfer. Surprisingly, four overlapping oligonucleotides, each consisting of at least two elements of the -6.1-kb enhancer, confer myeloid-cell-specific enhancer activity. We found several myeloid-cell-specific DNA-binding proteins interacting with the -6.1-kb enhancer, a result consistent with that described above. Therefore, we suggest that more than a single trans-acting factor mediates the cell type specificity of the -6.1-kb enhancer.
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59
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Steinfaith M, Schmitz W, Scholz H, von der Leyen H, Hecht A, Haverich A, Heublein B. Beta-adrenergic receptor number in surgically denervated, transplanted human hearts. Anesthesiology 1992; 76:863-4. [PMID: 1315489 DOI: 10.1097/00000542-199205000-00034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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60
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Hecht A. [Medicine in the controversy between traditional thinking and conceptual change in science]. MEDIZINISCHE KLINIK (MUNICH, GERMANY : 1983) 1992; 87:42-6. [PMID: 1545770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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61
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Bonifer C, Hecht A, Saueressig H, Winter DM, Sippel AE. Dynamic chromatin: the regulatory domain organization of eukaryotic gene loci. J Cell Biochem 1991; 47:99-108. [PMID: 1757483 DOI: 10.1002/jcb.240470203] [Citation(s) in RCA: 97] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
It is hypothesized that nuclear DNA is organized in topologically constrained loop domains defining basic units of higher order chromatin structure. Our studies are performed in order to investigate the functional relevance of this structural subdivision of eukaryotic chromatin for the control of gene expression. We used the chicken lysozyme gene locus as a model to examine the relation between chromatin structure and gene function. Several structural features of the lysozyme locus are known: the extension of the region of general DNAasel sensitivity of the active gene, the location of DNA-sequences with high affinity for the nuclear matrix in vitro, and the position of DNAasel hypersensitive chromatin sites (DHSs). The pattern of DHSs changes depending on the transcriptional status of the gene. Functional studies demonstrated that DHSs mark the position of cis-acting regulatory elements. Additionally, we discovered a novel cis-activity of the border regions of the DNAasel sensitive domain (A-elements). By eliminating the position effect on gene expression usually observed when genes are randomly integrated into the genome after transfection, A-elements possibly serve as punctuation marks for a regulatory chromatin domain. Experiments using transgenic mice confirmed that the complete structurally defined lysozyme gene domain behaves as an independent regulatory unit, expressing the gene in a tissue specific and position independent manner. These expression features were lost in transgenic mice carrying a construct, in which the A-elements as well as an upstream enhancer region were deleted, indicating the lack of a locus activation function on this construct. Experiments are designed in order to uncover possible hierarchical relationships between the different cis-acting regulatory elements for stepwise gene activation during cell differentiation. We are aiming at the definition of the basic structural and functional requirements for position independent and high level gene expression. The result of these experiments will have important consequences for random gene transfer with predictable and reproducible expression of transgenes.
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62
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Hecht A. [Pay attention in seborrheic eczema. Dermatoses as markers for HIV infection]. FORTSCHRITTE DER MEDIZIN 1991; 109:20. [PMID: 1839017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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63
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Tan A, Holdener GP, Hecht A, Gelfand C, Baker B. Malignant thymoma in an ectopic thymus: CT appearance. J Comput Assist Tomogr 1991; 15:842-4. [PMID: 1885808 DOI: 10.1097/00004728-199109000-00024] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
To our knowledge, malignant thymoma arising from an ectopic thymus gland has not been reported. Described below is such a case.
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64
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Mamon JF, Tan A, Pyati P, Hecht A. Unusual volar dislocation of the lunate into the distal forearm: case report. THE JOURNAL OF TRAUMA 1991; 31:1316-8. [PMID: 1920566 DOI: 10.1097/00005373-199109000-00019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A case of a severe wrist injury (fractures of the scaphoid, capitate, hamate, and ulnar styloid process) with volar dislocation of the lunate into the soft tissues of the forearm is presented. This degree of displacement of the lunate is exceedingly rare, and we believe has not been previously reported. Possible mechanisms, hyperextension injury forcing the lunate forward out of the carpus, or contact between the volar wrist skin surface and another object or surface propelling the dislocated lunate into the forearm, are discussed.
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65
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Hecht A. [Wholeness and diversity--their reflection in medical science]. ZEITSCHRIFT FUR ARZTLICHE FORTBILDUNG 1991; 85:683-6. [PMID: 1926939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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66
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Hecht A. [Causes or condition complex in the etiology of diseases]. ZEITSCHRIFT FUR ARZTLICHE FORTBILDUNG 1991; 85:487-90. [PMID: 1858399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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67
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Hecht A, Kühne W. [Gustav Ricker (1870-1948)--his life and work]. DER PATHOLOGE 1990; 11:313-5. [PMID: 2263569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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68
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Hecht A. [Autopsy findings and pathologic-anatomic epicrisis]. DER PATHOLOGE 1990; 11:197-200. [PMID: 2204908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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69
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Hecht A. [Progress in pathology?]. DER PATHOLOGE 1990; 11:61-3; discussion 64. [PMID: 2315279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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70
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Sippel AE, Stief A, Hecht A, Müller A, Theisen M, Borgmeyer U, Rupp RAW, Grewal T, Grussenmeyer T. The Structural and Functional Domain Organization of the Chicken Lysozyme Gene Locus. ACTA ACUST UNITED AC 1989. [DOI: 10.1007/978-3-642-83709-8_9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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71
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Hecht A, Berkenstam A, Strömstedt PE, Gustafsson JA, Sippel AE. A progesterone responsive element maps to the far upstream steroid dependent DNase hypersensitive site of chicken lysozyme chromatin. EMBO J 1988; 7:2063-73. [PMID: 3416833 PMCID: PMC454488 DOI: 10.1002/j.1460-2075.1988.tb03046.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
We have investigated the influence of the 5'-flanking region of the chicken lysozyme gene on steroid dependent gene expression. By transient transfection of lysozyme-CAT fusion genes into the human breast cancer cell line T-47D, a DNA element was identified which stimulates CAT expression when transfected cells are treated with progesterone. This element is distinct from a second hormone responsive element (HRE) located in the lysozyme promoter region; it activates the lysozyme and the TK promoter, irrespective of orientation and distance, and is therefore referred to as hormone responsive element on its own. The location of this newly discovered HRE between -2250 and -1815 relative to the transcriptional start site, corresponds to the position of a steroid inducible DNase I-hypersensitive site in chromatin of oviduct cells. This observation suggests a physiological role for the upstream element. In vitro DNase I protection experiments revealed six binding sites for both progesterone and glucocorticoid receptors within the sequences of the upstream HRE. The three distal binding sites are not required for hormonal stimulation of the TK promoter, while the three proximal binding sites, which are contiguously arranged, work in a cooperative manner.
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Bonifer C, Hecht A, Peters CW, Sippel AE. Rat antibodies as probes for the characterization of progesterone receptor A and B proteins from laying hen oviduct cytosol. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 968:96-108. [PMID: 3337848 DOI: 10.1016/0167-4889(88)90049-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The chicken oviduct contains two different hormone binding forms of the progesterone receptor, A and B. We have prepared rat antisera against both forms of the receptor partially purified from laying hen oviduct. The anti-progesterone receptor A antiserum reacts with both receptor forms on Western blots, while the anti-progesterone receptor B antiserum reacts mainly with the B form. Both antisera also react with the native progesterone receptor proteins as shown by sedimentation analysis of the antibody-receptor complexes. Receptors A and B are recognized on Western blots of total protein from dissolved tissue, indicating that both forms are likely to be physiological components. Epitope mapping experiments show that immunogenicity of both receptor molecules is restricted to structurally related protein domains of 28 kDa in receptor A and of 52 kDa in receptor B.
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73
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Trimper B, Massmann J, Bach G, Hecht A, Gebhardt G. Histoautoradiographic detection of 3H-thymidine and 3H-proline in the vascular wall of domestic swine in experimental atherosclerosis. Is there an effect of saturated/unsaturated fatty acids in high cholesterol diet? EXPERIMENTAL PATHOLOGY 1988; 34:99-103. [PMID: 3197797 DOI: 10.1016/s0232-1513(88)80037-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In vitro labeling of arterial wall samples from domestic swine with tritiated thymidine or proline was used to establish the effect of unsaturated (sunflower oil) or saturated (beef tallow) fatty acids in the presence of enteral cholesterol on DNA and collagen synthesis. Histoautoradiography of samples incubated in vitro gives labeling patterns and indices comparable to in vivo labeling. Preliminary results show that these nutrient fats do not differ in their effect on the DNA and collagen synthesis of vascular wall cells both in the presence and absence of intimal changes.
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74
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Hecht A. [Introduction to current problems in arteriosclerosis research]. ZEITSCHRIFT FUR DIE GESAMTE INNERE MEDIZIN UND IHRE GRENZGEBIETE 1986; 41:385-7. [PMID: 3765738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Preliminarily is referred to essential aspects of the aetiology of arteriosclerosis with particular consideration of the disturbed lipoprotein metabolism. Morphologically in the centre of pathogenetic considerations is the behaviour of the endothelial cells, the smooth muscle cells and the blood macrophages. As in many cases open problems we refer to the different participation of various arterial parts of the vessels in the arteriosclerotic process, to the necessity of a further clarification of the role of the thrombocytes in the initial phase of the arteriosclerosis as well as to the monocytes and their possible importance for the elimination of lipids from the vascular wall, the influence of drugs on the proliferation of smooth muscle cells and the formation of extracellular matrix, the question of the regression of arteriosclerotic changes, the reduction of risk factors and their influence on the regression of morphological changes in various developmental stages of arteriosclerosis. It is referred to the possible importance of macrophages and their metabolism as markers for the recognition of risk-endangered persons. Furthermore is emphasized the importance of models for the clarification of the pathomechanism of the arteriosclerosis as well as of the cell culture and of perfusion models.
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75
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Hecht A. Support groups: when going it alone is going nowhere. FDA CONSUMER 1986; 20:29-31. [PMID: 10311468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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