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Magowan C, Brown JT, Liang J, Heck J, Coppel RL, Mohandas N, Meyer-Ilse W. Intracellular structures of normal and aberrant Plasmodium falciparum malaria parasites imaged by soft x-ray microscopy. Proc Natl Acad Sci U S A 1997; 94:6222-7. [PMID: 9177198 PMCID: PMC21030 DOI: 10.1073/pnas.94.12.6222] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Soft x-ray microscopy is a novel approach for investigation of intracellular organisms and subcellular structures with high spatial resolution. We used x-ray microscopy to investigate structural development of Plasmodium falciparum malaria parasites in normal and genetically abnormal erythrocytes and in infected erythrocytes treated with cysteine protease inhibitors. Investigations in normal red blood cells enabled us to recognize anomalies in parasite structures resulting from growth under unfavorable conditions. X-ray microscopy facilitated detection of newly elaborated structures in the cytosol of fixed, unstained, intact erythrocytes, redistribution of mass (carbon) in infected erythrocytes, and aberrant parasite morphology. In cysteine protease inhibitor-treated, infected erythrocytes, high concentrations of material were detected in abnormal digestive vacuoles and aggregated at the parasite plasma membrane. We have demonstrated that an abnormal host erythrocyte skeleton affects structural development of parasites and that this aberrant development can be detected in the following generation when parasites from protein 4.1-deficient red blood cells infect normal erythrocytes. This work extends our current understanding of the relationship between the host erythrocyte membrane and the intraerythrocytic malaria parasite by demonstrating for the first time that constituents of the erythrocyte membrane play a role in normal parasite structural development.
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27
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Gabski HP, Lauschke G, Heck J, Semel J. 2. Numerische Simulation des Strömungsfeldes in Rührbehältern und Vergleich mit Meßergebnissen. CHEM-ING-TECH 1996. [DOI: 10.1002/cite.330680904] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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28
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Berger R, Gjedde A, Rischke R, Müller E, Heck J, Krieglstein J, Jensen A. Local cerebral glucose utilization in fetal guinea pigs at 0.75 gestation. Eur J Obstet Gynecol Reprod Biol 1996; 66:175-8. [PMID: 8735743 DOI: 10.1016/0301-2115(96)02403-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
OBJECTIVE Using the 2-deoxyglucose method, measurements of local cerebral glucose utilization in large fetal animals are very difficult and expensive. To circumvent these problems we recently modified the 2-deoxyglucose method for use in the fetal guinea pig in utero (Berger et al., J Neurochem 1994; 63: 271-279). The present study was designed to measure the rates of local cerebral glucose utilization in fetal guinea pigs at 0.75 of gestation. STUDY DESIGN After intravenous injection of 14C 2-deoxyglucose into the dams, local cerebral glucose utilization of the fetuses was measured from the time integral of the tracer in the maternal plasma and the autoradiographically determined concentration of the tracer in various parts of the fetal brain. RESULTS Fetal cerebral glucose utilization was low as compared to adult animals and varied in different brain structures from 19 +/- 4 to 29 +/- 7 mumol/100 g/min. CONCLUSION This study demonstrates the feasibility to measure local cerebral glucose utilization in undisturbed fetal guinea pigs in utero. We conclude that the low rate of cerebral glucose utilization and its small overall variability may reflect the neurological immaturity of the fetal brain.
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29
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Heck J, Baker G. The scholar's workstation project at the University of Tennessee. LIBRARY HI TECH 1995. [DOI: 10.1108/eb047954] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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30
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Heck J. Regina health district & management. Southern Saskatchewan Stroke Prevention Unit. AXONE (DARTMOUTH, N.S.) 1994; 16:36. [PMID: 7727294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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31
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Percec V, Heck J, Johansson G, Tomazos D, Kawasumi M, Ungar G. Molecular-Recognition-Directed Self-Assembly of Supramolecular Polymers. JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 1994. [DOI: 10.1080/10601329409349776] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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32
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Berger R, Gjedde A, Heck J, Müller E, Krieglstein J, Jensen A. Extension of the 2-deoxyglucose method to the fetus in utero: theory and normal values for the cerebral glucose consumption in fetal guinea pigs. J Neurochem 1994; 63:271-9. [PMID: 8207433 DOI: 10.1046/j.1471-4159.1994.63010271.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Fetal cerebral metabolism changes during development. The normal fetal metabolic rate must be known to evaluate pathophysiological changes. Therefore, we determined the regional cerebral glucose consumption in the fetal guinea pig. This required the application of the 2-deoxyglucose method to this species. We measured both the transfer coefficients of deoxyglucose and glucose between the maternal arterial plasma and the fetal brain and the lumped constant in chronically prepared undisturbed guinea pig dams using a three-compartment model. Furthermore, the ratio between the initial clearances of deoxyglucose and glucose between the maternal arterial plasma and the fetal brain and the ratio between the phosphorylation coefficients of these substrates in the fetal brain were determined. The total cerebral glucose consumption measured by the deoxyglucose method (10 +/- 1.2 mumol/100 g/min) was similar to that calculated from the glucose concentration and the phosphorylation coefficient of glucose in the cerebrum (10 +/- 0.4 mumol/100 g/min). We conclude that the 2-deoxyglucose method is applicable to the guinea pig, and we further conclude that in the fetal guinea pig cerebral glucose consumption is 10 times lower than that in the adult.
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Ungar G, Batty SV, Percec V, Heck J, Johansson G. Structure and conductivity of liquid crystal channel-like linic complexes of taper-shaped compounds. ACTA ACUST UNITED AC 1994. [DOI: 10.1002/amo.860040410] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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34
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van der Linden J, Heck J, Walther B, Böttcher HC. Electrochemical investigation of the electron-poor/precise (n=5/6) complexes [Fe2(CO)n(μ-PR2)(μ-PR′2)] (n=5, RR′But; n=6, RR′Ph; RBut, R′Ph; RBut, R′Cy). EPR study of the radical anion [Fe2(μ-PBut2)2(CO)5]·.−. Inorganica Chim Acta 1994. [DOI: 10.1016/0020-1693(93)03748-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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35
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van den Berg W, Boot C, van der Linden J, Bosman W, Smits J, Beurskens P, Heck J. Two silicon-bridged cyclopentadienyl Fe2S4 cluster units connected through an Fe(III)S6 unit. Crystal and molecular structure of [((CH3)2SiCp′2)2Fe5(μ3-S2)2(μ4-S2)2(μ4-S4)]FeCl4. Inorganica Chim Acta 1994. [DOI: 10.1016/0020-1693(93)03719-q] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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36
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Percec V, Heck J, Johansson G, Tomazos D, Kawasumi M, Ungar G. Molecular-Recognition-Directed Self-Assembly of Supramolecular Polymers. JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 1994. [DOI: 10.1080/10601329408545688] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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37
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Percec V, Heck J, Johansson G, Tomazos D, Kawasumi M, Chu P, Ungar G. Molecular Recognition Directed Self-Assembly of Supramolecular Architectures. JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 1994. [DOI: 10.1080/10601329408545879] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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38
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Heck J. Drug testing. J Athl Train 1993; 28:197-8. [PMID: 16558226 PMCID: PMC1317708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
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39
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Percec V, Heck J. Liquid crystalline polymers containing mesogenic units based on half-disc and rod-like moieties. Polym Bull (Berl) 1991. [DOI: 10.1007/bf00310233] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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40
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Percec V, Heck J. Liquid crystalline polymers containing mesogenic units based on half-disc and rod-like moieties. I. Synthesis and characterization of 4-(11-undecan-1-yloxy)-4′-[3,4,5-tri(p-n-dodecan-1-yloxybenzyloxy)benzoate]biphenyl side groups. ACTA ACUST UNITED AC 1991. [DOI: 10.1002/pola.1991.080290416] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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41
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Bierhoff E, Schmieder R, Heck J, Pfeifer U. [Cardiac involvement in non-Hodgkin's lymphoma]. Dtsch Med Wochenschr 1991; 116:491-5. [PMID: 2007379 DOI: 10.1055/s-2008-1063638] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In a 47-year-old man with non-Hodgkin's lymphoma which had been treated by polychemotherapy and radiation, cardiac involvement was suspected on computed tomography (CT) two years after diagnosis. The ECG demonstrated atrial flutter and a slow ventricular rate. After a further cycle of chemotherapy the patients declined further treatment. Two years later he was admitted urgently because of cardiac failure, atrial fibrillation with a slow ventricular rate, and clear signs of abnormal repolarization. CT of the thorax again provided signs of cardiac involvement with lymphoma. In addition there were extensive tumour infiltrates in the liver and paraaortic lymph-node. Despite intensive medical treatment he died shortly after admission from cardiac failure. At necropsy all four cardiac chambers and the coronary arteries were surrounded completely by tumour tissue. The membranous interventricular septum, the area of the Hiss bundle and the tricuspid and mitral valves had also been infiltrated. Histologically the infiltrates consisted of lymphoid cells of centrocytic type. Increasing tumour cell involvement went together with complete disintegration of myocardial fibres.
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42
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Heck J, Heinecke G. [Anxiety before gastrointestinal endoscopy]. Dtsch Med Wochenschr 1991; 116:356. [PMID: 1997312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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43
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Percec V, Heck J. Liquid crystalline polymers containing mesogenic units based on half-disc and rod-like moieties. Polym Bull (Berl) 1991. [DOI: 10.1007/bf00338899] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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44
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Percec V, Heck J. Liquid crystalline polymers containing mesogenic units based on half-disc and rod-like moieties. Polym Bull (Berl) 1990. [DOI: 10.1007/bf00306572] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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45
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46
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Hesch RD, Heck J, Delling G, Keck E, Reeve J, Canzler H, Schober O, Harms H, Rittinghaus EF. Results of a stimulatory therapy of low bone metabolism in osteoporosis with (1-38)hPTH and diphosphonate EHDP. Protocol of study I, osteoporosis trial Hannover. KLINISCHE WOCHENSCHRIFT 1988; 66:976-84. [PMID: 3141672 DOI: 10.1007/bf01738113] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In contrast to prevention, the therapy of manifest osteoporosis remains a clinically significant problem. So far all therapeutic attempts have yielded unsatisfying results. For this reason we have tried to achieve a positive bone balance by sequential stimulation and inhibition of the osseous metabolism. The therapy consisted of six 14-day courses with 400 units (1-38)hPTH per day and, in addition, starting with the 2nd week of PTH therapy, EHDP 5 mg per kg body weight per day for a total of 2 weeks. Already the initial therapeutic course resulted in a stimulation of decreased bone metabolism which could be documented by an increase in the calcium-47 accretion rate (six patients). An increase of the alkaline phosphatase could be noted (four patients); this, however, did not correlate with the calcium accretion. A positive calcium balance could, nonetheless, only be attained in four of eight patients within this period, while neither the alkaline phosphatase nor the kinetics would allow a prediction of this effect. Changes of the balance coincided with equal changes in the net calcium absorption. The urinary calcium excretion increased temporarily during the therapeutic phase. We were not able to detect an influence on the vitamin D metabolites. Histomorphometric studies did not demonstrate an increase in bone mass in the iliac creast after six therapeutic courses. Nevertheless, progressive deformations of vertebral bodies did not occur. We conclude that already after 2 weeks this therapeutic concept can lead to a stimulation of bone metabolism.
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47
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Heinecke G, Heck J. [Effectiveness of the electrohydrothermoprobe in gastrointestinal hemorrhages]. MEDIZINISCHE KLINIK (MUNICH, GERMANY : 1983) 1987; 82:571-2. [PMID: 3498880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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48
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Heck J. [Malignant lymphoma of the small intestine after long-existent sprue]. Dtsch Med Wochenschr 1984; 109:1988. [PMID: 6510250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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49
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Hesch RD, Heck J, Auf'mKolk B, Schettler T, Atkinson MJ. First clinical observations with hPTH(1-38), a more potent human parathyroid hormone peptide. Horm Metab Res 1984; 16:559-60. [PMID: 6500494 DOI: 10.1055/s-2007-1014852] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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50
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Heck J. [Leishmaniasis and fertility cult. Interpretation of facial mutilations in Moche art]. Dtsch Med Wochenschr 1982; 107:872-4. [PMID: 7044738 DOI: 10.1055/s-0029-1236757] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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