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Pilacinski W, Crawford A, Downey R, Harvey B, Huber S, Hunst P, Lahman L, MacIntosh S, Pohl M, Rickard C, Tagliani L, Weber N. Plants with genetically modified events combined by conventional breeding: An assessment of the need for additional regulatory data. Food Chem Toxicol 2011; 49:1-7. [DOI: 10.1016/j.fct.2010.11.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Revised: 10/29/2010] [Accepted: 11/03/2010] [Indexed: 10/18/2022]
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N'Gabou D, Magdeleinat P, Weber N, Raynaud C, Gossot D, Mechouek A, Stern JB. [Pleuropulmonary involvement leading to bilateral pneumothorax in a patient being treated for rheumatoid arthritis]. Rev Mal Respir 2010; 27:1119-23. [PMID: 21111289 DOI: 10.1016/j.rmr.2010.04.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Accepted: 04/17/2010] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Rheumatoid arthritis (RA) is a systemic illness where the development of pulmonary nodule has been described in from 4 to 20% of patients. Symptomatic pleural manifestations occur in 3 to 5% of cases. Rarely, pulmonary nodules become necrotic and lead to pleural complications. Bilateral pneumothorax has only rarely been described. CASE REPORT We report the case of a 64-year-old woman, who had been treated for RA for several years and presented with bilateral pneumothorax secondary to necrobiosis of one or several pulmonary rheumatoid nodules. The management of the pneumothorax was very prolonged and difficult, and despite surgical pleurodesis, the lung did not reexpand fully. Pathological examination of the pleura revealed a noncaseating granulomatous pattern. The diagnosis of a sarcoidosis like disease, possibly induced by anti-TNFα, or of pleural tuberculosis were suggested, but we concluded that the final diagnosis was of pleural rheumatoid involvement. CONCLUSION Bilateral pneumothorax secondary to rheumatoid nodule is a rare entity. The management of such a complication is difficult, particularly in patients who receive an immunosuppressant regimen. A granulomatous pattern has been described rarely in the pleural tissue of these patients. Specific RA pleural involvement has to be taken in consideration when other diagnoses are eliminated, especially tuberculosis or sarcoidosis-like disease.
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Weber N, Lee YS, Shanmugasundaram S, Jaffe M, Arinzeh T. Characterization and in vitro cytocompatibility of piezoelectric electrospun scaffolds. Acta Biomater 2010; 6:3550-6. [PMID: 20371302 DOI: 10.1016/j.actbio.2010.03.035] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 02/15/2010] [Accepted: 03/23/2010] [Indexed: 02/02/2023]
Abstract
Previous studies have shown that electrical charges influence cell behavior (e.g. enhancement of nerve regeneration, cell adhesion, cell morphology). Thus, piezoelectric scaffolds might be useful for various tissue engineering applications. Fibrous scaffolds were successfully fabricated from permanent piezoelectric poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) by the electrospinning technique. Scanning electron microscopy and capillary flow analyses verified that the fiber mats had an average fiber diameter of 970 +/- 480 nm and a mean pore diameter of 1.7 microm, respectively. Thermally stimulated depolarization current spectroscopy measurements confirmed the piezoelectric property of the PVDF-TrFE fibrous scaffolds by the generation of a spontaneous current with the increase in temperature in the absence of an electric field, which was not detected in the unprocessed PVDF-TrFE powder. Differential scanning calorimetry, thermogravimetric analysis, X-ray diffraction and Fourier transform infrared spectroscopy results showed that the electrospinning process increased the crystallinity and presence of the polar, beta-phase crystal compared with the unprocessed powder. Confocal fluorescence microscopy and a cell proliferation assay demonstrated spreading and increased cell numbers (human skin fibroblasts) over time on PVDF-TrFE scaffolds, which was comparable with tissue culture polystyrene. The relative quantity of gene expression for focal adhesion proteins (measured by real-time RT-PCR) increased in the following order: paxillin < vinculin < focal adhesion kinase < talin. However, no differences could be seen among the TCPS surface and the fibrous scaffolds. Future studies will focus on possible applications of these cytocompatible PVDF-TrFE scaffolds in the field of regenerative medicine.
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Baron C, Weber N, Neumayr A, Niebauer E, Häußinger K. Hausstaubmilben: Eine neue Methode zur Allergenreduktion. Pneumologie 2010. [DOI: 10.1055/s-0030-1251142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Daum J, Weber N, Hoelters J, Häußinger K. Sauerstoffgabe bei Alltagstätigkeit bei Patienten mit COPD im Stadium III und IV nach GOLD: Wirksamkeit in Abhängigkeit vom Stadium. Pneumologie 2010. [DOI: 10.1055/s-0030-1251178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Meyer T, Müllinger B, Sommerer K, Scheuch G, Brand P, Beckmann H, Häussinger K, Weber N, Siekmeier R. PULMONARY DEPOSITION OF MONODISPERSE AEROSOLS IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE. Exp Lung Res 2009; 29:475-84. [PMID: 14710439 DOI: 10.1080/01902140303775] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
In order to improve patient convenience and drug availability for patients with alpha 1-protease inhibitor deficiency, the administration via the inhalation route has been considered. This study investigated if it is possible to obtain high values of peripheral aerosol deposition by using optimized and controlled inhalation conditions. Therefore, peripheral deposition was studied in 10 patients with alpha 1-protease inhibitor deficiency (phenotype PiZ) and moderate to severe chronic obstructive pulmonary disease by measuring the 24-hour Clearance of radiolabeled inert iron oxide particles with diameters of 2 microns, 3 microns, and 4 microns. Patients inhaled a large volume of aerosol (1000 to 2000 cm3), which was normalized to the individual lung function, with a flow rate of 200 cm3/S. Due to this breathing pattern, peripheral deposition was for all particle sizes above 50% of the inhaled aerosol. The highest peripheral deposition (68%) was found for 3-microns particles.
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Hunger T, Schulze A, Meyer T, Weber N. Erhöhung des Erkenntnisgewinns durch Kombination von Fragebögen zur Geräteanwendung und zum Gesundheitszustand. Pneumologie 2009. [DOI: 10.1055/s-0029-1214105] [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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Esche B, Weber N, Geiseler J, Karg O. Praktische Schulung der Anwendung von Pulver-Inhalationshilfen bei Patienten mit COPD: Ist sie erfolgreich? Pneumologie 2009. [DOI: 10.1055/s-0029-1213901] [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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Möller W, Möller T, Heimbeck I, Weber N, Kempa A, Körner B, Kohlhäufl M. Fraktionierte Sammlung von Atemkondensat: Exhaliertes Wasserstoffperoxid (H2O2) stammt aus den Atemwegen. Pneumologie 2009. [DOI: 10.1055/s-0029-1214063] [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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Menn P, Weber N, Häußinger K, Holle R. Lebensqualität bei Patienten mit COPD während akuter Exazerbation: Vergleich von EQ-5D, SF-12 und SGRQ. Pneumologie 2009. [DOI: 10.1055/s-0029-1214106] [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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Möller W, Heimbeck I, Weber N, Kempa A, Körner B, Kohlhäufl M. Fraktionierte Sammlung von Atemkondensat: Exhaliertes Wasserstoffperoxid (H2O2) stammt aus den Atemwegen. Pneumologie 2009. [DOI: 10.1055/s-0029-1213598] [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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Vosmann K, Wiege B, Weitkamp P, Weber N. Preparation of lipophilic alkyl (hydroxy)benzoates by solvent-free lipase-catalyzed esterification and transesterification. Appl Microbiol Biotechnol 2008; 80:29-36. [PMID: 18542947 DOI: 10.1007/s00253-008-1534-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2007] [Revised: 05/06/2008] [Accepted: 05/06/2008] [Indexed: 11/28/2022]
Abstract
Long-chain alkyl benzoates, e.g., lauryl 4-hydroxybenzoate, palmityl 4-hydroxybenzoate, and oleyl 4-hydroxy-3-methoxybenzoate, are formed in high to moderate conversion by lipase-catalyzed transesterification of the corresponding short-chain alkyl benzoates (0.3 to 1 mmol) with fatty alcohols in an equimolar ratio. The substrates are reacted in vacuo in the absence of solvents and drying agents in the reaction mixture. Immobilized lipase B from Candida antarctica (Novozym 435) demonstrates higher activity for the transesterification of various methyl (hydroxy)benzoates with long-chain alcohols than for the corresponding esterification reactions. For example, transesterification activity is around 25-fold higher than esterification activity for the preparation of oleyl 4-hydroxybenzoate. The relative transesterification activities of methoxy- and hydroxy-substituted methyl benzoates found for Novozym 435 are as follows: 2-methoxybenzoate approximately 3-methoxybenzoate > 4-methoxybenzoate > 3-hydroxybenzoate approximately 2-hydroxybenzoate > 4-hydroxybenzoate approximately 4-hydroxy-3-methoxybenzoate approximately 3-hydroxy-4-methoxybenzoate > > 3,4-dihydroxybenzoate. With respect to the position of the substituents at the phenyl moiety of methyl benzoates, transesterification activity of Novozym 435 increases in the order ortho approximately meta > para. Compounds with inverse chemical structure, e.g., (methoxy)benzyl alkanoates, are formed in much higher rates both by esterification and transesterification than the analogous alkyl benzoates. Purification by deacidification, crystallization, or vacuum distillation yielded 74% to 89% of the reaction products.
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Esche B, Weber N, Geiseler J, Karg O. Inhalationssysteme: Welche sind die häufigsten Fehler bei der Anwendung? Pneumologie 2008. [DOI: 10.1055/s-2008-1074329] [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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Weber N, Daum J, Hoelters J, Häußinger K. Sauerstoffgabe bei Alltagstätigkeit bei Patienten mit COPD: Ist sie hilfreich? Pneumologie 2008. [DOI: 10.1055/s-2008-1074120] [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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Kim JT, Weber N, Shin GH, Huang Q, Liu SX. The study of beta-lactoglobulin adsorption on polyethersulfone thin film surface using QCM-D and AFM. J Food Sci 2008; 72:E214-21. [PMID: 17995774 DOI: 10.1111/j.1750-3841.2007.00344.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The adsorption process of beta-lactoglobulin on the polyethersulfone-coated surface has been investigated using a quartz crystal microbalance with dissipation monitoring (QCM-D), which allowed simultaneous measurements of frequency and energy dissipation changes caused by the formation of a beta-lactoglobulin layer during the protein adsorption process. The results showed that the protein adsorption on the spin-coated polyethersulfone surface consisted of reversible and irreversible adsorption processes, and the irreversible adsorption was the principal factor to cause the permanent protein adsorption onto the polymer surface. The amount of irreversible adsorption of beta-lactoglobulin increased significantly, from 380.5 +/- 23.2 to 745.5 +/- 29.7 ng/cm2, when the concentration of beta-lactoglobulin solution varied from 0.1% to 2.0% (w/v). The pH also played an important role in the protein adsorption. When the pH of the solution varied from 7.0 to 3.0, the amount of irreversible adsorption of beta-lactoglobulin increased from 427.1 +/- 80.7 to 741.2 +/- 135.1 ng/cm2.
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Fehling E, Klein E, Vosmann K, Bergander K, Weber N. Linear copolymeric poly(thia-alkanedioates) by lipase-catalyzed esterification and transesterification of 3,3′-thiodipropionic acid and its dimethyl ester with α,ω-alkanediols. Biotechnol Bioeng 2008; 99:1074-84. [DOI: 10.1002/bit.21704] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Devillière M, Ingen-Housz-Oro S, Weber N, Cordoliani F, Vignon-Pennamen MD, Manciet JR, Sigal-Grinberg M. Élastome perforant serpigineux induit par D-pénicillamine. Ann Dermatol Venereol 2007; 134:799-800. [DOI: 10.1016/s0151-9638(07)92548-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Cavailhes A, Ingen-Housz-Oro S, Djennane S, Rafaa M, Fiszenson-Albala F, Weber N, Sigal-Grinberg M. Survenue d’un psoriasis au cours d’un traitement par infliximab pour fasciite de Shulman. Ann Dermatol Venereol 2007; 134:363-7. [PMID: 17483757 DOI: 10.1016/s0151-9638(07)89192-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Anti-TNFalpha drugs are used in certain rheumatologic and gastrointestinal inflammatory diseases and are also effective in cutaneous psoriasis. Several case reports have recently been published concerning induction of paradoxical psoriasis during the course of anti-TNF therapy. We report a new case involving infliximab used to treat Shulman fasciitis. CASE REPORT A 39-year-old woman was treated with infliximab for corticoid-dependent Shulman fasciitis. No personal or familial cutaneous psoriasis was noted in her history. Two months after the third infusion, she developed psoriasis vulgaris and pustular palmoplantar psoriasis which improved under topical corticosteroids. Her psoriatic lesions worsened one month after the first maintenance infusion. Since the Shulman fasciitis was not under control, infliximab was withdrawn and replaced with azathioprine. Six months later, her psoriasis was in remission and the Shulman fasciitis was under control. DISCUSSION TNFalpha plays an important role in the physiopathology of psoriasis through its action on inflammatory infiltrate, angiogenesis and keratinocyte proliferation. Several studies have reported the efficiency of TNFalpha inhibitors in moderate to severe cutaneous psoriasis. However, fourteen cases of induction or worsening of psoriasis have been reported with these drugs, suggesting a class effect. We report a new case of cutaneous psoriasis induced by infliximab in a patient presenting corticoid-dependent Shulman fasciitis, and we discuss the possible immunological mechanisms responsible for this paradoxical side effect. Other cutaneous lesions have been reported during treatment with TNFalpha inhibitors. The benefits of this treatment on the underlying inflammatory disease must be balanced against the potential cutaneous side effects when deciding whether to continue with anti-TNFalpha treatment.
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Wegerle S, Markus A, Weber N, Steffen H, King B, Eder W, Philipp E, Morresi-Hauff A, Häussinger K, Hoffmann H. [Pulmonary nocardiosis with trimethoprime/sulphamethoxazole-resistant Nocardia paucivorans in a patient with no signs of immunosuppression]. Pneumologie 2007; 61:46-51. [PMID: 17253210 DOI: 10.1055/s-2006-944276] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This is so far the first published case report of a Nocardia paucivorans infection in an immunocompetent patient. A 54-year-old farmer was hospitalised with a history of coughing and fever for a period of five months. There was no indicator of either primary of secondary immunodeficiency in the prior medical history. A chest X-ray showed pneumonic infiltrates in the right middle und lower lobes, which progressed despite of antibiotic therapy with macrolides. A transbronchial biopsy revealed unspecific granulomatous inflammation of soft tissues. N. paucivorans - grew in cultures of sputum, bronchoalveolar lavage, and transbronchial biopsy. Oral antibiotic therapy was started with trimethoprime-sulphamethoxazole (TMP/SMX) and amoxicillin plus clavulanic acid. Susceptibility testing revealed high level resistance to TMP/SMX, which was consequently replaced by ciprofloxacin. Six months later, infiltrates had completely resolved and the patient did not report any residual clinical symptoms. The present case showed once again that nocardiosis is not limited to patients with immunodeficiencies. However, conservative combination therapy with oral antibiotics seems to be sufficiently effective for nocardiosis in the immunocompetent patient. For cases of suspected nocardiosis, a step-wise, risk-based diagnostic and therapeutic procedure is proposed.
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Dauendorffer JN, Ingen-Housz-Oro S, Levy P, Weber N, Fiszenson-Albala F, Sigal-Grinberg M. [Pancreatic panniculitis revealing a pancreaticportal fistula and portal thrombosis]. Ann Dermatol Venereol 2007; 134:249-52. [PMID: 17389850 DOI: 10.1016/s0151-9638(07)91818-9] [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: 11/29/2022]
Abstract
BACKGROUND Pancreatic panniculitis is a rare condition that usually occurs in association with acute or chronic pancreatitis or pancreatic carcinoma. We report a case of pancreatic panniculitis revealing a pancreaticportal fistula and portal thrombosis. CASE REPORT A 79-year-old man was admitted for nodular panniculitis of the lower extremities without any digestive symptoms. Laboratory tests revealed very high plasma levels of amylase and lipase. A skin biopsy showed lobular panniculitis with ghost cells characteristic of pancreatic panniculitis. Rare pancreatic calcifications and portal thrombosis were seen on an abdominal CT scan and on endoscopic ultrasound examination of the pancreas. A pancreaticportal fistula was detected by endoscopic retrograde pancreatography. Finally, an endoscopic pancreatic prothesis was inserted in Wirsung's canal after failure of medical treatment (parenteral nutrition and octreotide). Skin lesions resolved and plasma pancreatic enzymes normalized. DISCUSSION This case report is interesting because of the lack of gastrointestinal symptoms associated with pancreatic panniculitis and the discovery of a chronic pancreatitis of uncertain etiology. This case highlights the need to screen for pancreaticportal fistula and portal thrombosis, which are often associated with pancreatic panniculitis.
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Akoglu B, Kindl P, Weber N, Trojan J, Caspary WF, Faust D. Polymorphisms in the methylenetetrahydrofolate reductase gene are determinant for vascular complications after liver transplantation. Eur J Clin Nutr 2007; 62:430-5. [PMID: 17311050 DOI: 10.1038/sj.ejcn.1602699] [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: 01/14/2023]
Abstract
OBJECTIVE The aim of this study was to evaluate the role of the C677T-MTHFR (methylenetetrahydrofolate reductase)-polymorphism (CC, CT and TT) for vascular complications in liver transplant recipients. DESIGN Retrospective study. SETTING Hepatology-Transplantation-Unit, Johann Wolfgang Goethe-University, Frankfurt am Main. SUBJECTS 48 liver transplant recipients were included, no dropouts. METHODS MTHFR polymorphism was detected by PCR amplification and digestion with Hinfl restriction enzyme. Vascular complications after liver transplantation were detected from the patients' records. The total serum homocysteine (HCY) was analyzed with high-pressure liquid chromatography. RESULTS In the wild-type group (CC), the HCY levels were slightly high (14.0+/-1 micro M). Among the patients with the CT polymorphism, the HCY values were elevated (22.5+/-3 micro M). In the homozygous TT group, there was a significant increase (31.2+/-6 micro M, P<0.01) of the HCY values. The percentage of vascular complications was higher in the heterozygous CT (47%) and homozygous TT (62.5%) group compared with wild-type CC (21%). Patients with a homozygous TT genotype of the MTHFR polymorphism with a vascular complication had a highly significant elevated HCY level compared to the other genotype groups, both with and without any vascular complications (P<0.001). Recipients with an elevated HCY and the TT polymorphism have a higher probability of developing a vascular complication after transplantation (odds ratio: 4.3 and 11.0; 95% confidence interval: 1.15, 12.25 and 1.41, 85.24). CONCLUSIONS The C677T polymorphism in the MTHFR gene and subsequent elevation of the total serum HCY is significantly associated with an increased incidence of vascular complications in liver transplant recipients.
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Fehling E, Klein E, Weber N, Demes C, Vosmann K. Chemo-enzymatic preparation of copolymeric polythioesters containing branched-chain thioether groups. Appl Microbiol Biotechnol 2007; 74:357-65. [PMID: 17103159 DOI: 10.1007/s00253-006-0677-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2006] [Revised: 09/11/2006] [Accepted: 09/12/2006] [Indexed: 11/24/2022]
Abstract
Branched-chain copolymeric polythioesters (PTE) were formed in good yield (approximately 87%) by chemoenzymatic reactions including thiyl radical-induced addition of 1,6-hexanedithiol to the >C=C< double bond of dimethyl 1,18-octadec-9-enedioate and transthioesterification of polyfunctional dimethyl 1,18-octadec-9-enedioate with bifunctional 1,6-hexanedithiol catalyzed by immobilized lipase from Rhizomucor miehei. The reactions were performed in vacuo at 80 degrees C without a solvent. PTE was extracted from the reaction mixture using methyl-t-butylether and precipitated from i-hexane. The polymer structure of the i-hexane-insoluble PTE precipitate was elucidated by GPC/SEC showing an average molecular mass (Mw) of 1,857 Da corresponding to a molecular weight range of up to 24,000 Da and a maximum degree of polymerization of up to 50 monomer units. Chemical derivatization with TMSH demonstrated the formation of up to approximately 58 mol% of a branched-chain thio(S)ether, i.e., dimethyl S-9-(6-mercaptohexylthio)-1,18-octadecanedioate, and small proportions (approximately 8 mol%) of a dimeric disulfide formed therefrom. The chemical structures of various low-molecular weight (<900 Da) reaction products formed by transthioesterification, addition reaction or disulfide formation of the reactants or reaction intermediates, e.g., 1,18-octadec-9-enedioic acid methyl(O)ester 6'-S-mercaptohexyl thio(S)ester, dimethyl S-9-(6-mercaptohexylthio)-1,18-octadecanedioate, were elucidated by GC-MS. Similarly, dimethyl S-9-(6-S-methylthiohexylthio)-1,18-octadecanedioate and dimethyl 11,18,19,26-tetrathia-10,27-di-(7-carboxymethyl-heptyl)hexatriacontane-1,36-dioate were detected in the reaction mixtures after derivatization with trimethylsulfonium hydroxide.
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Wätjen W, Weber N, Lou YJ, Wang ZQ, Chovolou Y, Kampkötter A, Kahl R, Proksch P. Prenylation enhances cytotoxicity of apigenin and liquiritigenin in rat H4IIE hepatoma and C6 glioma cells. Food Chem Toxicol 2007; 45:119-24. [PMID: 17045382 DOI: 10.1016/j.fct.2006.08.008] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2006] [Revised: 07/21/2006] [Accepted: 08/14/2006] [Indexed: 10/24/2022]
Abstract
Antioxidative as well as cytotoxic effects of the prenylated flavonoids licoflavone C (8-prenylapigenin) and isobavachin (8-prenylliquiritigenin) were investigated in comparison to the corresponding non-prenylated flavonoids (apigenin, liquiritigenin) and vitexin (apigenin-C8-glucoside) using metabolically active H4IIE hepatoma and metabolically poorly active C6 glioma cells. None of the substances showed radical scavenging activities in the 2,2-diphenyl-1-picrylhydrazyl (DPPH)-assay nor were they effective in protection against H2O2-induced intracellular 2',7'-dichlorodihydrofluorescein (H2DCF) oxidation (fluorescent probe for oxidative stress) in H4IIE and C6 cells. When the intrinsic effects of the substances were investigated, licoflavone C and isobavachin exerted a pronounced toxicity in both H4IIE (IC50 values of 42+/-5 and 96+/-19 micromol/L) and C6 cells (IC50 values of 37+/-6 and 69+/-3 micromol/L) while the non-prenylated analogues as well as the glycosylated derivate vitexin showed almost no cytotoxic effect up to 250 micromol/L. In H4IIE cells the induction of apoptotic cell death by licoflavone C and icobavachin was detected as an activation of caspase 3/7 (6- and 3.3-fold, respectively). Based on these experiments we suggest that C8-prenylation of a flavonoid enhances the cytotoxicity inducing an apoptotic cell death in H4IIE cells without affecting antioxidative properties.
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Wegerle S, Weber N, Häußinger K, Hoffmann H. Risiko-stratifizierte Therapie der Nokardiose in West-Europa. Pneumologie 2007. [DOI: 10.1055/s-2007-973352] [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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Weber N, Daum J, Jakob M, Morresi-Hauf A, Stanzel F, Häußinger K. Kontralaterale hiläre und mediastinale Lymphknoten bei Z.n. Pneumonektomie wegen Plattenepithelkarzinom: Metastasen oder ...? Pneumologie 2007. [DOI: 10.1055/s-2007-973177] [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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