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Koch K, van den Berg RJF, Nieuwland PJ, Wijtmans R, Schoemaker HE, van Hest JCM, Rutjes FPJT. Enzymatic enantioselective C-C-bond formation in microreactors. Biotechnol Bioeng 2008; 99:1028-33. [PMID: 17879309 DOI: 10.1002/bit.21649] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We have demonstrated that multiple crude enzyme lysates containing a hydroxynitrile lyase can be used for the enantioselective synthesis of cyanohydrins from aldehydes in microchannels. Using a microreactor setup, two important parameters were efficiently screened consuming only minute amounts of reagents. More importantly, results from the continuous flow reaction were fully consistent with results obtained from larger batchwise processes in which a stable emulsion was formed.
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Koch K, Wagner G, Nenadic I, Schachtzabel C, Schultz C, Roebel M, Reichenbach JR, Sauer H, Schlösser RGM. Fronto-striatal hypoactivation during correct information retrieval in patients with schizophrenia: an fMRI study. Neuroscience 2008; 153:54-62. [PMID: 18359576 DOI: 10.1016/j.neuroscience.2008.01.063] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2007] [Revised: 12/14/2007] [Accepted: 01/23/2008] [Indexed: 10/22/2022]
Abstract
Working memory (WM) deficits are core symptoms of schizophrenia. Differing behavioral performance is known to represent a potent moderating variable when investigating the neural correlates of working memory in patients with schizophrenia compared with healthy controls. The present functional magnetic resonance imaging study examined performance-matched cerebral activity during correct WM retrieval by balancing the mean number of correct responses as well as the mean response times between patients and controls and analyzing remaining correct trials. Forty-one schizophrenia patients and 41 healthy controls performed an event-related Sternberg task allowing for analysis of correctly remembered trials. Correct retrieval was associated with activation in a bilateral fronto-parieto-occipital network comprising mainly the dorsolateral prefrontal cortex, ventrolateral prefrontal cortex and superior parietal cortex in controls and, to a weaker degree, in patients. Direct group comparison revealed significantly decreased activations in patients in the posterior (Brodmann area (BA) 31) and anterior (BA 32) cingulate cortex (ACC) and the medial caudate bilaterally when matching for performance. When matching for performance and response speed there was additional hypoactivation in the insula. Mean response times were negatively correlated with cingulate and caudate activation only in controls. Present findings suggest that during efficient WM retrieval processing patients exhibit only slightly impaired activation in a task-specific network containing mainly prefrontal and superior parietal areas. However, hypoactivation of areas predominantly responsible for cognitive control and response execution seems to remain even under performance-matched conditions. Given the relevant role of the caudate and the ACC in dopaminergically mediated executive processing, the results bear crucial implications for the psychopathology of schizophrenia.
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Malich A, Koch K, Kott A, Ulrich A, Mikulik S, Gorna R, Hentrich D. Vergleich zweier CAD-Systeme in der Analyse der Dynamik histologisch gesicherter Brustläsionen in der MR-Mammographie. ROFO-FORTSCHR RONTG 2008. [DOI: 10.1055/s-2008-1073927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Schlösser R, Koch K, Wagner G. Assessing the State Space of the Brain with fMRI: An Integrative View of Current Methods. PHARMACOPSYCHIATRY 2007. [DOI: 10.1055/s-2007-992769] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Mantke R, Niepmann D, Gastinger I, Lippert H, Koch K, Quehl A. [Hepatic resections. Analysis of data from the Tumor Documentation Center in the state of Brandenburg, Germany, focusing on liver metastases of colorectal carcinoma]. Chirurg 2007; 77:1135-43. [PMID: 17091286 DOI: 10.1007/s00104-006-1247-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND Data from the Brandenburg Tumor Documentation Center (TDCB) in Germany were analyzed for an overview of the current treatment standards of liver surgery in that state. MATERIAL AND METHODS The analysis was based on prospective data from a total of 37,165 patients diagnosed with malignant tumors between 1 January 1999 and 31 December 2004. Of these patients, 3,986 were diagnosed with liver metastases and 554 had primary tumors of the liver or bile duct. Liver metastases of colorectal carcinoma were reported in 1,299. RESULTS Analysis confirmed that resection of colorectal metastases (51%) and primary liver or bile duct tumors (23.1%) is by far the most frequent indication for liver surgery. Liver metastasis was developed by 29.2% (n=1299) of patients with colorectal carcinoma. Of the patient total, 71.5% showed evidence of liver metastasis already present when colorectal carcinoma was diagnosed. Of 248 patients who had received liver surgery after diagnosis of liver metastases of a colorectal carcinoma, 114 (46%) underwent hepatic segment resection, which was thus performed in only 8.8% (n=114) of patients with liver metastases after colorectal carcinoma (n=1299). CONCLUSIONS Since only 8.8% of those with liver metastases underwent curative hepatic segment resection, we can conclude that if patients and doctors were provided with adequate information on the curative potential of this surgical method along with regular consultations with surgeons experienced in liver surgery, the result on resection rates would be positive. Data from tumor documentation centers enable selective analysis of the oncological situation of specific diseases.
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Koch K, Wagner G, Nenadic I, Schachtzabel C, Roebel M, Schultz C, Axer M, Reichenbach JR, Sauer H, Schlösser RGM. Temporal modeling demonstrates preserved overlearning processes in schizophrenia: an fMRI study. Neuroscience 2007; 146:1474-83. [PMID: 17448605 DOI: 10.1016/j.neuroscience.2007.03.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Revised: 03/13/2007] [Accepted: 03/16/2007] [Indexed: 10/23/2022]
Abstract
Working memory (WM) deficits are a core feature of schizophrenia. However, it has not been examined whether these deficits are related to altered temporal dynamics of information acquisition and changes in executive cognitive control. Therefore, the present study intended to quantify and model the dynamic process of information acquisition during continuous overlearning of WM information. It also aimed at investigating the relation between overlearning-associated change in behavioral performance and brain activity. Thirteen schizophrenic patients and 13 healthy volunteers were studied with functional magnetic resonance imaging (fMRI) while performing a recently developed overlearning paradigm [Koch K, Wagner G, von Consbruch K, Nenadic I, Schultz C, Ehle C, Reichenbach J, Sauer H, Schlösser R (2006) Temporal changes in neural activation during practice of information retrieval from short-term memory: An fMRI study. Brain Res 1107:140-150]. Consistent with the earlier study, short-term learning of stimulus material was associated with significant performance improvements and exponential signal decreases in a fronto-parieto-cerebellar network both in schizophrenic patients and in healthy volunteers. Against expectation patients exhibited stronger signal decreases relative to controls in anterior cingulate (Brodmann area (BA) 32), middle and superior temporal (BA 37, BA 22), superior frontal (BA 8/9, BA 6) and posterior parietal regions (BA 40). Furthermore, the individually modeled exponential decay rate of the blood oxygenation level-dependent signal in the right dorsolateral prefrontal cortex was significantly correlated with exponential decrease in mean behavioral response times in healthy controls while a statistical trend emerged in patients. A relative hyperactivation in the patient group was observable only at the start of the learning process and diminished with continued overlearning. This effect might indicate a gradual reduction of recruited neuronal resources and a practice-associated activation normalization in patients with schizophrenia. Our data suggest that in subacute patients learning and associated decreases in cerebral activation brought about by short-term practice are left unimpaired.
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Keay S, Tocci G, Koch K, Zhang C, Grkovic D, Michejda C. 276 POSTER The frizzled 8-related antiproliferative factor from IC patients inhibits bladder and kidney carcinoma cell proliferation in vitro. EJC Suppl 2006. [DOI: 10.1016/s1359-6349(06)70281-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Winzer T, Cant B, Taylor N, Masters J, Kneight A, Attwood T, Boorman J, Koch K, Nutland S, Watkins N, Ouwehand WH. P66 The UK Blood Service/Wellcome Trust Control Collection: a unique public resource of control samples for disease association studies. Transfus Med 2006. [DOI: 10.1111/j.1365-3148.2006.00694_66.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Talley NJ, Camilleri M, Burton D, Thomforde G, Koch K, Rucker MJ, Peterson J, Zinsmeister AR, Earnest DL. Double-blind, randomized, placebo-controlled study to evaluate the effects of tegaserod on gastric motor, sensory and myoelectric function in healthy volunteers. Aliment Pharmacol Ther 2006; 24:859-67. [PMID: 16918891 DOI: 10.1111/j.1365-2036.2006.03049.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND The effects of tegaserod on gastric accommodation and postprandial satiety remain unclear. AIM To compare the effects of tegaserod 6 mg twice daily vs. placebo on gastric volumes, postprandial symptoms, gastric emptying, small bowel transit and the surface electrogastrogram in female and male healthy volunteers. METHODS Randomized, double-blind, placebo-controlled study evaluated gastric function before and after 7 days of tegaserod 6 mg twice daily (n = 21) vs. placebo (n = 20) in healthy volunteers. Validated methods were used to study gastric emptying, myoelectrical activity, volumes and satiation postnutrient challenge. RESULTS There were no significant effects of tegaserod on the primary endpoints assessing gastric function: emptying of solids or liquids, total gastric volumes or myoelectrical activity. Maximum tolerated volume and aggregate symptom score with nutrient challenge on placebo were 1,035 mL (+/-44) and 130 (+/-15) vs. 989 mL (+/-43) and 117 (+/-15) during tegaserod, respectively (all P = N.S.). Postprandial change in proximal gastric volume by single photon emission-computed tomography was decreased in females on tegaserod (246 +/- 30) vs. placebo (358 +/- 32) (P = 0.015). Proximal fasting volumes in females were increased on tegaserod (126 +/- 12) vs. placebo (92 +/- 13) (P = 0.066). CONCLUSIONS While tegaserod decreased proximal gastric volume change after a meal, it does not appear to have significant effects on gastric motor and sensory function in healthy individuals. Further studies are required in patients with disturbances of gastric motor and sensory function.
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Ensikat HJ, Boese M, Mader W, Barthlott W, Koch K. Crystallinity of plant epicuticular waxes: electron and X-ray diffraction studies. Chem Phys Lipids 2006; 144:45-59. [PMID: 16879815 DOI: 10.1016/j.chemphyslip.2006.06.016] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2005] [Accepted: 06/19/2006] [Indexed: 11/30/2022]
Abstract
The crystal structure of the epicuticular waxes of 35 plant species has been examined by electron diffraction and X-ray powder diffraction. The waxes include the most common morphological wax types such as platelets, tubules, films and rodlets. Most of them were prepared with a special mechanical isolation method, which preserves the original crystal structure. Solvent-extracted recrystallized plant waxes were compared with mechanically isolated samples. The waxes were found to occur in three different crystal structures. Most of the waxes exhibited an orthorhombic structure which is the most common for aliphatic compounds. Tubules containing mainly secondary alcohols showed diffraction reflections of a triclinic phase; broad reflection peaks indicated a significant disorder. Ketones, in particular beta-diketone tubules, displayed the reflections of a hexagonal structure. Mixtures of different phases could be identified. For most of the waxes, the 'long spacing' diffraction reflections indicated a layer structure with the characteristics of the major component. Others showed no 'long spacing' reflections indicating a strong disorder of the molecular layers.
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Miglarese MR, Wallace E, Woessner R, Allen S, Hans J, Lemieux C, Dewolf W, Lyssikatos J, Lee P, Koch K. ARRY-649, a member of a novel class of Eg5 kinesin inhibitors. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.13045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
13045 Background: Inhibitors of the Eg5 motor kinesin selectively disrupt mitotic spindles in dividing cells. This selective targeting of microtubule dynamics in dividing cells is expected to translate to broad-spectrum anti-tumor activity while avoiding neuropathic side effects caused by taxanes. To date, quinazolinone Eg5 inhibitors, exemplified by ispinesib, represent the only Eg5 inhibitors reported in clinical trials. Methods: We used X-ray crystallography, biochemical and cell-based assays, pharmacokinetic profiling and in vivo efficacy studies to identify and optimize a potent series of Eg5 inhibitors. Results: We have discovered a distinct series of potent Eg5 inhibitors, exemplified by ARRY-649. ARRY-649 inhibited Eg5 with an IC50 of 0.7 nM, blocked phosphorylation of histone H3 in HeLa cells with an IC50 of 0.3 nM and showed sub-nanomolar activity against a broad panel of human tumor cells lines in in vitro viability assays. Further evaluation of mechanism-of-action in tumor cell lines revealed that ARRY-649 induced a monopolar spindle phenotype and subsequent apoptosis characteristic of Eg5 inhibition. In contrast to paclitaxel, ARRY-649 retained potent activity against multi-drug resistant human tumor cells lines selected to overexpress P-glycoprotein. ARRY-649 demonstrated robust efficacy in the HT-29 human colon tumor xenograft model and was well-tolerated at efficacious doses and schedules. Durable complete- and partial-regressions were observed upon intraperitoneal administration on a 5 mg/kg q4dx3 schedule in the HT-29 model. Similar results were obtained using the HL-60 myelomonocytic xenograft model. Conclusions: ARRY-649 represents a distinct class of potent Eg5 inhibitors with robust activity in preclinical models of human cancer. Based on these observations, we have progressed novel Eg5 inhibitors toward clinical development. [Table: see text]
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Kunz RP, Koch K, Kreitner KF. Kardiale Funktionsanalyse mittels MRT und CT sowie MR-Flussmessung. ROFO-FORTSCHR RONTG 2006. [DOI: 10.1055/s-2006-940300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Koch K, Barthlott W, Koch S, Hommes A, Wandelt K, Mamdouh W, De-Feyter S, Broekmann P. Structural analysis of wheat wax (Triticum aestivum, c.v. 'Naturastar' L.): from the molecular level to three dimensional crystals. PLANTA 2006; 223:258-70. [PMID: 16133211 DOI: 10.1007/s00425-005-0081-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2005] [Accepted: 07/08/2005] [Indexed: 05/04/2023]
Abstract
In order to elucidate the self assembly process of plant epicuticular waxes, and the molecular arrangement within the crystals, re-crystallisation of wax platelets was studied on biological and non-biological surfaces. Wax platelets were extracted from the leaf blades of wheat (Triticum aestivum L., c.v. 'Naturastar', Poaceae). Waxes were analysed by gas chromatography (GC) and mass spectrometry (MS). Octacosan-1-ol was found to be the most abundant chemical component of the wax mixture (66 m%) and also the determining compound for the shape of the wax platelets. The electron diffraction pattern showed that both the wax mixture and pure octacosan-1-ol are crystalline. The re-crystallisation of the natural wax mixture and the pure octacosan-1-ol were studied by scanning tunnelling microscopy (STM), atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Crystallisation of wheat waxes and pure octacosano-1-ol on the non polar highly ordered pyrolytic graphite (HOPG) led to the formation of platelet structures similar to those found on the plant surface. In contrast, irregular wax morphologies and flat lying plates were formed on glass, silicon, salt crystals (NaCl) and mica surfaces. Movement of wheat wax through isolated Convallaria majalis cuticles led to typical wax platelets of wheat, arranged in the complex patterns typical for C. majalis. STM of pure octacosan-1-ol monolayers on HOPG showed that the arrangement of the molecules strictly followed the hexagonal structure of the substrate crystal. Re-crystallisation of wheat waxes on non-polar crystalline HOPG substrate showed that technical surfaces could be used to generate microstructured, biomimetic surfaces. AFM and SEM studies proved that a template effect of the substrate determined the orientation of the re-grown crystals. These effects of the structure and polarity of the substrate on the morphology of the epicuticular waxes are relevant for understanding interactions between biological as well as technical surfaces and waxes.
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Kunz RP, Gössler F, Herber S, Kramm T, von Bardeleben RS, Koch K, Pitton B, Düber C, Kreitner KF. Nicht-invasive Abschätzung des pulmonalarteriellen Mitteldrucks bei CTEPH-Patienten mittels Phasenkontrast-Flussmessungen. ROFO-FORTSCHR RONTG 2006. [DOI: 10.1055/s-2006-940715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Koch K, Suhling F. Do behavioural and life-history traits vary with mate-guarding intensity in libellulid odonates? CAN J ZOOL 2005. [DOI: 10.1139/z05-163] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
It has been demonstrated that in libellulid dragonflies the distribution of eggs during oviposition and the offspring size vary with the type of mate guarding during oviposition (non-contact guarding and contact guarding). In this study, we investigated the hypothesis that oviposition behaviour and life-history traits also differ between these two guarding types. Therefore, we studied oviposition behaviour and life-history traits in six species of a dragonfly assemblage of the Namib Desert. Among the oviposition behaviours, oviposition duration and number of pond changes differed significantly between the guarding types. Clutch size did not differ between the guarding types, whereas some offspring characters, namely egg width, temperature sum to hatch, and larval head width, differed between the guarding types. Eggs of tandem species (those performing contact guarding) were larger, which might explain differences in all other offspring characters studied; bigger eggs need a lower temperature sum for egg development, result in bigger larvae, and have a faster growth rate, all traits that might be seen as an adapation to temporary waters, which are major habitats of the tandem species. This observation is discussed in the light of different dispersal strategies between the species performing different guarding types.
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Koch K, Wagner G, von Consbruch K, Nenadic I, Schultz CC, Ehle C, Reichenbach JR, Sauer H, Schlösser R. Differential temporal dynamics of cognitive learning processes in patients with schizophrenia: An event-related fMRI study. PHARMACOPSYCHIATRY 2005. [DOI: 10.1055/s-2005-918745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Salmassi A, Schmutzler AG, Schaefer S, Koch K, Hedderich J, Jonat W, Mettler L. Is granulocyte colony-stimulating factor level predictive for human IVF outcome? Hum Reprod 2005; 20:2434-40. [PMID: 15890733 DOI: 10.1093/humrep/dei071] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND We investigated granulocyte colony-stimulating factor (G-CSF) in human reproduction. METHODS From a total sample of 93 patients, we analysed in group 1 (n = 82) the level of G-CSF and estradiol (E(2)) in serum and follicular fluid (FF) on day of follicular puncture (FP). Furthermore, in response to ovarian stimulation, G-CSF levels in serum were compared between low (n = 11), moderate (n = 53) and high (n = 18) response patients. In group 2 (n = 23) serum for G-CSF assessment was collected throughout menstrual cycle until gestation. Group 3 (n = 11) patients with endometriosis were assessed for G-CSF in serum and FF on day of FP without further differentiation. RESULTS G-CSF in FF was higher than in serum (P < 0.01). G-CSF in serum increased from low through moderate to high response (P < 0.001); pregnancy rates were 0, 24.5 and 33.5% respectively. G-CSF in serum increased throughout stimulation, reached a peak with ovulation induction (P = 0.01) and decreased until embryo transfer (P=0.001). G-CSF level only in pregnant patients (n = 11) increased from embryo transfer to implantation to gestation (P = 0.005). In endometriosis patients G-CSF in serum and FF was lower than in non-endometriosis patients (P < or = 0.03) and corresponded with low response patients. CONCLUSIONS G-CSF is involved in follicle development and may be a predictor of IVF outcome.
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Koch K, Oellig F, Kunz P, Bender P, Oberholzer K, Mildenberger P, Hake U, Kreitner KF, Thelen M. [Assessment of global and regional left ventricular function with a 16-slice spiral-CT using two different software tools for quantitative functional analysis and qualitative evaluation of wall motion changes in comparison with magnetic resonance imaging]. ROFO-FORTSCHR RONTG 2005; 176:1786-93. [PMID: 15573290 DOI: 10.1055/s-2004-813730] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
PURPOSE To determine global and regional left ventricular (LV) function from retrospectively gated multidetector row computed tomography (CT) by using two different semiautomated analysis tools and to correlate the results with those of magnetic resonance imaging (MRI). MATERIALS AND METHODS Nineteen patients (5 females, 14 males, mean age 69 years) underwent 16-slice spiral-CT (MS-CT) with standard technique without administration of beta-blockers for a decrease in the cardiac rate. Ten series of images were reconstructed at every 10 % of the RR-interval. With commercially available software capable of semiautomated contour detection, end-diastolic and end-systolic LV volumes (EDV and ESV) were determined from short-axis multiplanar CT reformations (MPR). Axial images of the end-systolic and end-diastolic cardiac phase were transformed to 3D volumes (3D) to determine EDV and ESV by using a threshold-supported reconstruction algorithm dependent on the contrast enhancement of the left ventricle. Steady-state free-precession cine MR images were acquired in short-axis orientation on the same day in all but one patient. Regional wall motion was assessed qualitatively in 17 left ventricular segments and classified as normo-, hypo-, a- or dyskinetic. Bland-Altman analysis was performed to calculate limits of agreement and systematic errors between CT and MRI. RESULTS For MPR/3D, mean end-diastolic (144.4/142.8 mL +/- 67.5/67.1) and end-systolic (66.4/68.7 mL +/- 52.1/49.9) LV volumes as determined with MS-CT correlated well with MRI measurements (147.6 mL +/- 67.6 [ r = 0.98/0.96] and 73.3 mL +/- 55.5 [ r = 0.98/0.98], respectively [ p <.001]). LV stroke volume (77.6/74.1 +/- 19.2/23.4 mL for CT vs. 74.4 mL +/- 18.4 for MRI, r = 0.92/0.74) and LV ejection fraction (58.6/55.9 % +/- 13.5/13.7 for CT vs. 55.6 % +/- 13.5 for MRI, r = 0.95/0.91) also showed good correlation (p <.001). Regional wall motion analysis revealed agreement between CT and MRI in 316/323 (97.8 %) myocardial segments. CONCLUSION Semiautomated analysis of 16-detector row CT data sets enables global and regional volumetric and functional analysis. The CT results correlate well with MRI findings for short axis MPR and for 3D volume reconstructions, with a higher statistical spread for the 3D method. The underestimation of end-systolic and end-diastolic volumes with CT may be caused by partial volume averaging due to the lower temporal resolution as compared with MRI.
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Koch K, Burgert R, Stösser G, Schnöckel H. Understanding of the structure, bonding, formation and decomposition of metalloid aluminum clusters--a Fourier transform ion cyclotron resonance study of solid AlCp*. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2005; 11:469-74. [PMID: 16322652 DOI: 10.1255/ejms.739] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The investigation of the tetrahedral Al4Cp*4 cluster with Fourier transform ion cyclotron resonance mass spectrometry using laser desorption /ionization as the ionization method results in a couple of aluminum cluster compounds AlxCp*+y (x > y) with up to eight aluminum atoms. MS(n) experiments are performed in order to understand the formation and reactivity of the different species. Quantum chemical calculations of the structure and energy for all compounds identified complete this study.
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Koch K, Oellig F, Oberholzer K, Bender P, Kunz P, Mildenberger P, Hake U, Kreitner KF, Thelen M. Assessment of right ventricular function by 16-detector-row CT: comparison with magnetic resonance imaging. Eur Radiol 2004; 15:312-8. [PMID: 15565315 DOI: 10.1007/s00330-004-2543-6] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2004] [Revised: 10/04/2004] [Accepted: 10/07/2004] [Indexed: 01/31/2023]
Abstract
The purpose of this study was to determine right ventricular (RV) function from 16-detector-row CT by using two different software tools in comparison with MRI. Nineteen patients underwent cardiac CT. (1) With semiautomated contour detection software end-diastolic and end-systolic RV volumes were determined from short-axis CT reformations (MPR) created at every 10% of the RR-interval. (2) End-systolic and end-diastolic axial images were transformed to 3D to determine the volumes by using a threshold-supported reconstruction algorithm. Steady-state free-precession cine-MRI of the heart was done in short-axis orientation. RV function could not be analyzed in one patient because of sternal wire artifacts in MRI. Mean end-diastolic (155.4+/-54.6 ml) and end-systolic (79.1+/-37.0 ml) RV volumes determined with MPR correlated well with MRI [151.9+/-53.7 ml (r=0.98) and 75.0+/-36.0 ml (r=0.96), respectively (P<0.001)]. RV stroke volume (76.2+/-20.2 ml for MPR-CT, 76.9+/-20.7 ml for MRI, r=0.93) showed a good correlation and RV ejection fraction (50.8+/-8.4% for MPR-CT, 51.9+/-7.4% for MRI, r=0.74) only a moderate one. Threshold supported 3D reconstructions revealed insufficient correlations with MRI (r=0.31-0.59). MPR-based semiautomated analysis of cardiac 16 detector-row CT allows for RV functional analysis. The results correlate well with MRI findings. Threshold value-supported 3D reconstructions did not show satisfying results because of inhomogeneities of RV contrast enhancement.
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Rudorf WD, Koch K, Augustin M. Reaktionen von Malonsäureethylesteraniliden mit Heterokumulenen. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/prac.19813230416] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Lakhai WS, Beijnen JH, Den Boer SS, Westermann AM, Versola M, Koch K, Ho P, Pandite L, Richel DJ, Schellens J. Phase I trial to determine the safety and tolerability of GW572016 in combination with oxaliplatin (OX)/5-fluorouracil (5-FU)/leucovorin (LV) [FOLFOX4] in patients with solid tumors. J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.2044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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