419 results on '"Ralf Westenfeld"'
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402. Cardiovascular complications - 2
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Vakur Akkaya, Erik Mistrik, Toshio Shimada, Carolyn van Eps, Sharam Taheri, Nobuyuki Oyake, Dimitrios Memmos, Yukinao Sakai, Shirin Karimi, Shuzo Kobayashi, Vanda Jorgetti, Igor Nikolov, Giusy Chiarelli, Alexander Lukasz, Genevieve Brin, Baki Yagci, Ralf Westenfeld, Young-Tai Shin, Kazuo Munakata, Aikaterini Papagianni, Kenichi Amitani, Ligia Petrescu, Georgios Efstratiadis, Ki Ryang Na, Jürgen Floege, Hidekazu Moriya, Elizabeta Srbinovska-Kostovska, Noemie Jourde Chiche, José Sampol, Sygliti-Errieta Pelidou, Seichi Kawata, Brian Haluska, Katia R. Neves, Ailong Huang, Satoshi Umemura, Terumasa Hayashi, Tadashi Kuji, Seiichi Kawata, Simonetta Genovesi, C. Klein, Daniela Pogliani, John Moorhead, Jaroslav Racek, Lada Malanova, Keiichi Fukudome, E. Rus, Xanthi Zikou, Tomonori Kimura, Bang-Gee Hsu, Efthimia Zafeiriadou, Jaromír Eiselt, Shuji Ono, Ali Basci, Dimitirios Memmos, Vladimir Blaha, M.J. Jardine, Andrzej Ksiazek, Beti Zafirova-Ivanovska, Grzegorz Wystrychowski, Hermann Haller, Shouichi Fujimoto, Yu-Hsien Lai, William Smith, Juan Jesus Carrero, Monica Beaulieu, Hideyuki Ochiai, Àngel Argilés, Marilena Gregorini, F. Guerrero, Shinji Hirawa, Dimitrios Kirmizis, Stéphane Robert, Machiko Oka, Gen Yasuda, Graham Smith, Mojgan Mortazavi Najafabadi, M.A. Roberts, Daniel Rajdl, C. Barbulescu, Ki Hyun Kim, Eleni Liakou, Adrian Covic, Xiong Ruan, Abdel-Bassit El-Shaarawy, Suhas Lele, James Chabu, Te-Chao Fang, Claire Cerini, Samuel Omotoye, Despina Karasavvidou, Mai Yanagi, Chrysostomos Dimitriadis, Sylvie Dusilová-Sulková, Thomas Marwick, Qing-Feng Han, Fellype C. Barreto, Asif Ansari, Sumi Hidaka, Ljubica Georgievska-Ismail, Lubos Sobotka, I. Lopez, Volker Kliem, Ralf Schindler, Sonja Trojacanec-Piponska, Anna Tankovics, H.J. Lambers Heerspink, Rieko Eriguchi, Eleonora Galbiati, Tomoyuki Murakami, Mariko Tatsumoto, Sanae Saka, Georg Schlieper, Kostas Katopodis, Stuart M. Cobbe, Umapati Hegde, Guerman Molostvov, Beyza Akdag, Tao Wang, Jolanta Szeliga-Król, Spyros Dovas, Seong Eun Kim, Yoshiyuki Toya, Shiva Seyrafian, Daniel Zehnder, Huseyin Oflaz, Esat Memisoglu, Rosemary Bland, Anna-Maria Belechri, Ai-Hua Zhang, C. Sintimbreanu, Kunihiro Ishioka, Sung-Hyun Son, Kang Wook Lee, Sascha David, Misao Tsukada, Asim Jagga, Maria Eugênia Fernandes Canziani, Saso Gelev, Teresa Rampino, Piyaporn Laouthaiwattana, Philippe Charpiot, Kazuhiro Yamada, T. Ninomiya, Rafael Ponikvar, Ko-Lin Kuo, Tushar Malavade, A. Cass, Shuichi Hisanaga, Daniela V. Barreto, Tsu-Wang Shen, Raymond Calaf, Pasquale Esposito, Szu-Chun Hung, Harald P. Kühl, Savas Tepe, Philipp Kümpers, Kostas C. Siamopoulos, Li-Tao Cheng, Takayasu Ohtake, Alaattin Yildiz, Simona Stancu, Dai Ohno, Won-Suk An, Ashraf El-Saeed, Hamdi Pusuroglu, Milan Korotvicka, Francoise Dignat George, Rajan K. Patel, Syuji Ono, Maryam Ghassami, Laurence Camoin Jau, Mariano Rodriguez, Fen Yang, Paul Taylor, Arben Asani, Kazuo Kitamura, Michael Boehme, Yuzuru Sato, Suneet Singh, Peter Stenvinkel, Simon Fletcher, F.J. Mendoza, Patrick B. Mark, Dan-Xia Zheng, Antonio Dal Canton, Adrian Zugravu, Takuya Ono, Keiko Suzuki, Chih-Hsien Wang, Kazuhiko Shibata, R. Martinescu, Keiko Yasuda, Naoki Kimata, Aleksandar Sikole, Stephen H. Powis, Karolina Kublickiene, Gabriel Mircescu, Jamal El-Kheshen, Kosaku Nitta, Kyoko Maesato, Alan G. Jardine, Adelheid Wilde, Ji-Yoon Jung, E. Aguilera-Tejero, Władysław Grzeszczak, Yoshitsugu Obi, Angela J. Woodiwiss, Asuka Aoki, Ali Poormoghadas, Halil Yazici, Kathy Nicholls, Eui-Sic Kim, David W. Mudge, Ryota Ikee, Kazuaki Tanabe, Jan T. Kielstein, Kalpesh Gohel, Der-Cherng Tarng, Rosa M.A. Moysés, Yukie Moriyama, Mirja Neizel, Han Lei, Nikola Stojcev, Shahid Anwar, Yoshihiro Takeda, Rigas Kalaitzidis, Leanid Luksha, Steven C. Campbell, Magda Samara, Hyun-Seung Yoo, Leanne Jeffries, Lemonia Skoura, Naoko Miwa, Michal Vostry, Kan Kikuchi, Naoaki Koguchi, Jadranka Buturović-Ponikvar, Kenjiro Honda, Banibrata Mukhopadhyay, Pavlina Dzekova, Andrea Stella, Henry J. Dargie, Takashi Akiba, Natallia Luksha, Andreja Marn Pernat, Sarah Chung, Gjulsen Selim, Malte Kelm, Pravin Manga, V. Perkovic, Anna-Maria Bellechri, Mehmet Batmazoglu, Wojciech Załuska, Leena Ong-Ajyooth, Daisaku Ando, Florence Sabatier, Kriengsak Vareesangthip, Hidehisa Satta, Nicole M. Isbel, Tsuneo Murasawa, Folke Hammarqvist, Daniel Zickler, Irena Rambabova-Busletic, Christoph Fischer, Tomoyuki Ohtsuka, Paolo Fabbrini, Dae-Eun Choi, Carmelo Libetta, Naadiya Docrat, Olaf Boenisch, Koichi Sasaki, Danilo Fliser, Antonio Vincenti, Thilo Krüger, Sishir Gang, Simin Rota, Yvon Berland, Eva Dounousi, Ladislav Trefil, Philippe Brunet, Efstathios Alexopoulos, Valentina Portalupi, Anna Bednarek-Skublewska, Fabiana Rodrigues Hernandes, Konstantinos Tsinoglou, Pınar Çakmak, Giulia Fantini, Mohan Rajapurkar, Manthan Kansara, Janine Jeffries, Carmel M. Hawley, Yuji Sato, Adeera Levin, David W. Johnson, Laura Cosmai, Yoshiyuki Nagai, Saraladevi Naicker, Laetitia Dou, Giuseppe Bonforte, Zeynab Alipoor, Christos Bantis, Alison Grieve, Aluizio B. Carvalho, Zac Varghese, Belda Dursun, Yaxi Chen, Gavin R. Norton, Stefano Severi, S. Zoungas, Olivera Stojceva-Taneva, Ewa Zukowska-Szczechowska, Tamio Iwamoto, and Abeed Jamal
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Transplantation ,medicine.medical_specialty ,Nephrology ,business.industry ,medicine ,Intensive care medicine ,business - Published
- 2009
403. Experimental pathology - 2
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Antonio C. Cordeiro, Dave Martin, Ralf Westenfeld, Maria Pia Rastaldi, Giuseppe Grandaliano, D. van der Giezen, Monique Kerroch, Laura Giardino, Xiaomei Li, Heidi Hedman, Mariarosa Arra, Hans J. Baelde, O. van Oostrom, Hung-Chun Chen, Vasiliki Mavroeidi, Vittoria Esposito, Kojiro Nagai, Giuseppe Remuzzi, Miriam Galbusera, Djurdjica Jovovic, Gianluigi Forloni, Anna Granqvist, Ryota Shirai, Jack F.M. Wetzels, Hidenori Arai, Tetsuhiro Tanaka, R. Goldschmeding, Vivette D. D'Agati, Sabine Leh, Caroline Le Van Kim, Ram Sharma, Benedicte Y. De Winter, Kerstin Ebefors, Alessandro Corbelli, Enrica Tosetto, Takanori Kumagai, Carla Zoja, Samih H. Nasr, Nicoletta Serpieri, Alain C. Borczuk, Karl F. Hilgers, Noemi Maggi, Mariadelfina Molinaro, Yongxi Chen, J.W. Leeuwis, Helmut Geiger, Oliver Jung, Jer-Ming Chang, Fieke Mooren, Irene L. Noronha, Garyfalia Perysinaki, Akira Mima, Piergiorgio Messa, Lei Qu, C. Migotto, Makoto Araki, Toru Kita, Georg Schlieper, Angela D'Angelo, Raghu Kalluri, Hanae Wakabayashi, Dimitrios Moisiades, Ikumi Sato, Monica Ceol, Aineng Liao, Marcus J. Moeller, A. Dendooven, Eduardo Barbosa-Sicard, Kostas Stylianou, Margarete Goppelt-Struebe, Young Sook Lee, Akiko Fujita, Toshio Miyata, Dino Martini, Luigi Villa, Bruce D. Hammock, Daniela Croci, Alireza Showraki, Fabio Sallustio, Ji Dong, Atsushi Fukatsu, Ioannis Petrakis, Tarak Srivastava, J. Joles, Virginia J. Savin, Qiuhua Huang, Antonio Dal Canton, Giuseppe Castellano, Masaomi Nangaku, Toshiro Fujita, Fatemmeh Emamghorashi, Luca De Benedictis, Weiming Wang, Alexandre C. Santana, Dorella Del Prete, Sanja Citlucanin, Filippo Mangione, Christian Ott, Vincenzo Costantino, Ciro Esposito, Toshio Doi, Annika Lindskog, Thilo Krueger, Bart Smeets, Pierre-Louis Tharaux, Lydia Nakopoulou, Gianluigi Zaza, Caroline A.J. Horvath, Cécile Rahuel, Paola Simonini, Sandra Uhlig, Juergen Floege, Kostas Perakis, Osamu Yokosuka, Bjarne M. Iversen, Marzia Pesaresi, Kristien J. Ledeganck, Masami Ikehata, Motoko Yanagita, Francesco Paolo Schena, Zoran Miloradovic, Nan Chen, Marina Morigi, Glen Markovitz, Novella Calvaresi, Astrid Fuss, Eugene Daphnis, Makoto Ogawa, Hiroshi Nishi, Franca Anglani, Sara Gastoldi, Markus P. Schlaich, Jin Huang, Naoki Morito, Roland E. Schmieder, Jeff Hodgin, Jean-Claude Dussaule, Christina Kastrinaki, Anne A. Filipe, Christos Chatziantoniou, Yuki Hamano, Kunihiro Yamagata, Wim Verelst, Satoru Takahashi, Johannes Bogers, Christian Delles, Zhangsuo Liu, Silvia Berra, Mukut Sharma, Nevena Mihailovic-Stanojevic, Ellen T. McCarthy, Sven Kroening, Markus Ketteler, Fernanda Cobuci, Enrico Pertile, Seyed Mohammad Owji, Jasmina Markovic-Lipkovski, Ji Young Han, Takashi Okude, Sandrine Placier, C. Snijckers, Reiko Inagi, Marianne C. Verhaar, Yves Colin, Genyang Cheng, Rita de Cássia Cavaglieri, Stavros Stratakis, Daniela Rottoli, Jenny Nyström, Takeshi Matsubara, Willi Jahnen-Dechent, Börje Haraldsson, Fabrizio Grosjean, Noriyuki Iehara, Anna Pezzotta, Ya Li, Silvia Armelloni, Keigyou Yoh, Shiro Ueda, T.Q. Nguyen, Marina Noris, Chiara Pagani, Francesca Castoldi, Ralf P. Brandes, Yoshihiko Ueda, Federica Mezzabotta, Markus P. Schneider, Michael Hultström, Emilia Tiralongo, Jürgen Floege, Deborah Mattinzoli, Ichiro Kojima, Jiansheng Li, Mohammad Moatamedfard, Monica Locatelli, Yu Wang, Dominique Guerrot, E.J. Robertson, Simona Buelli, Il Soo Ha, Christophe Morriseau, Felix Jansen, Min Li, Ju Hyung Kang, Peter Boor, Kazuo Torikoshi, Vincent Brandenburg, Antonia Loverre, Gert A. Verpooten, Liqiang Meng, and Kerstin Amann
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010309 optics ,Transplantation ,Pathology ,medicine.medical_specialty ,Nephrology ,business.industry ,010401 analytical chemistry ,0103 physical sciences ,medicine ,Experimental pathology ,business ,01 natural sciences ,0104 chemical sciences - Published
- 2009
404. Sympathetic hyperactivity influences chemosensor function in patients with end-stage renal disease
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Thomas Lauer, Tienush Rassaf, M Hennersdorf, Patrick Schauerte, Jan Balzer, Ralf Westenfeld, Malte Kelm, Christian Meyer, Schueller Po, and S Steiner
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Male ,medicine.medical_specialty ,Sympathetic nervous system ,Sympathetic Nervous System ,lcsh:Medicine ,End stage renal disease ,Internal medicine ,Reflex ,Heart rate ,medicine ,Humans ,Heart rate variability ,Aged ,Oxygen saturation (medicine) ,end-stage renal disease ,business.industry ,Research ,lcsh:R ,nervous system ,General Medicine ,Middle Aged ,sympathetic ,Crossover study ,Chemoreceptor Cells ,medicine.anatomical_structure ,Endocrinology ,Blood pressure ,Catecholamine ,Kidney Failure, Chronic ,Female ,business ,chemoreflexes ,medicine.drug - Abstract
Background Autonomic neuropathy is common in patients suffering from end-stage renal disease (ESRD). This may in part explain the high cardiovascular mortality in these patients. Chemosensory function is involved in autonomic cardiovascular control and is mechanistically linked to the sympathetic tone. Objective The aim of the present study was to assess whether sympathetic hyperactivity contributes to an altered chemosensory function in ESRD. Materials and methods In a randomized, double-masked, placebo controlled crossover design we studied the impact of chemosensory deactivation on heart rate, blood pressure and oxygen saturation in 10 ESRD patients and 10 age and gender matched controls. The difference in the R-R intervals divided by the difference in the oxygen pressures before and after deactivation of the chemoreceptors by 5-min inhalation of 7 L oxygen was calculated as the hyperoxic chemoreflex sensitivity (CHRS). Placebo consisted of breathing room air. Baseline sympathetic activity was characterized by plasma catecholamine levels and 24-h time-domain heart rate variability (HRV) parameters. Results Plasma norepinephrine levels were increased (1.6 ± 0.4 vs. 5.8 ± 0.6; P < 0.05) while the SDNN (standard deviation of all normal R-R intervals: 126.4 ± 19 vs. 100.2 ± 12 ms), the RMSSD (square root of the mean of the squared differences between adjacent normal R-R intervals: 27.1 ± 8 vs. 15.7 ± 2 ms), and the 24-h triangular index (33.6 ± 4 vs. 25.7 ± 3; each P < 0.05) were decreased in ESRD patients as compared to controls. CHRS was impaired in ESRD patients (2.9 ± 0.9 ms/mmHg, P < 0.05) as compared to controls (7.9 ± 1.4 ms/mmHg). On multiple regression analysis 24 h-Triangular index, RMSSD, and plasma norepinephrine levels were independent predictors of an impaired hyperoxic CHRS. Conclusion Sympathetic hyperactivity influences chemosensory function in ESRD resulting in an impaired hyperoxic CHRS.
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- 2009
405. THE IMPACT OF FETUIN-A, PHOSPHATE AND UREMIA ON THE INDUCTION OF EXTRAOSSEOUS CALCIFICATION IN MICE
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Vincent Brandenburg, Markus Ketteler, Ralf Smeets, Juergen Floege, Ralf Westenfeld, Cora Schaefer, and Willi Jahnen-Dechent
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medicine.medical_specialty ,business.industry ,General Medicine ,Phosphate ,medicine.disease ,Extraosseous Calcification ,Fetuin ,Uremia ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,Endocrinology ,chemistry ,Internal medicine ,medicine ,Cardiology and Cardiovascular Medicine ,business - Published
- 2004
406. Author Index/Subject Index Proceedings
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Gerhard Lonnemann, Marcelo Mazza do Nascimento, Ken Okumura, Jenny Cross, Roberto Pecoits-Filho, Willi Jahnen-Dechent, Jürgen Floege, Machteld M. Zweers, Raymond T. Krediet, Hiroshi Osawa, Dirk G. Struijk, Cees Vermeer, Hideaki Yamabe, Miguel C. Riella, Kerstin Amann, Sadie van Esch, Vera Krane, Peter Stenvinkel, Hirofumi Tomita, Matthias Girndt, Tilman B. Drüeke, Karin Tyralla, Tomohiro Osanai, Christoph Wanner, Naoto Fujiwara, Masayuki Nakamura, Marja M. Ho-dac-Pannekeet, Raymond Vanholder, Satoko Sasaki, Masayuki Saitoh, Bengt Lindholm, Markus Ketteler, Ralf Westenfeld, Wieneke M. Michels, Véronique Witko-Sarsat, Watske Smit, Ziad A. Massy, Paul Jungers, Peter J. Ratcliffe, W. Van Biesen, Béatrice Descamps-Latscha, and Carmine Zoccali
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Index (economics) ,Nephrology ,Statistics ,Subject (documents) ,Hematology ,General Medicine ,Psychology - Published
- 2002
407. Author Index Abstracts
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Hirofumi Tomita, Hideaki Yamabe, Watske Smit, Naoto Fujiwara, Tomohiro Osanai, Ken Okumura, Bengt Lindholm, Vera Krane, Sadie van Esch, Christoph Wanner, Masayuki Nakamura, Satoko Sasaki, Raymond Vanholder, Karin Tyralla, Gerhard Lonnemann, Carmine Zoccali, Markus Ketteler, W. Van Biesen, Peter Stenvinkel, Matthias Girndt, Kerstin Amann, Marja M. Ho-dac-Pannekeet, Hiroshi Osawa, Dirk G. Struijk, Jenny Cross, Béatrice Descamps-Latscha, Marcelo Mazza do Nascimento, Machteld M. Zweers, Roberto Pecoits-Filho, Willi Jahnen-Dechent, Tilman B. Drüeke, Wieneke M. Michels, Ziad A. Massy, Peter J. Ratcliffe, Ralf Westenfeld, Masayuki Saitoh, Véronique Witko-Sarsat, Cees Vermeer, Miguel C. Riella, Raymond T. Krediet, Jürgen Floege, and Paul Jungers
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Index (economics) ,Nephrology ,Statistics ,Hematology ,General Medicine ,Mathematics - Published
- 2002
408. Do not be misguided by guidelines: the calcium phosphate product can be a Trojan horse.
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Markus Ketteler, Vincent Brandenburg, Willi Jahnen-Dechent, and Ralf Westenfeld
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- 2005
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409. Underestimated complications in thrombotic thrombocytopenic purpura—haemolytic uraemic syndrome.
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Vincent M. Brandenburg, Sören Gaertner, Katharina Lindemann-Docter, Jan R. Ortlepp, Ralf Westerhuis, Markus Ketteler, Ralf Westenfeld, and Jürgen Floege
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- 2004
410. Nitric oxide synthase isoform expression in acute versus chronic anti-Thy 1 nephritis
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Martin Paul, Alexander Gawlik, Sebastian Bachmann, Ralf Westenfeld, Armin Distler, Emile De Heer, Gilbert Schönfelder, Markus Ketteler, and Alexander Frey
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medicine.medical_specialty ,Nitric Oxide Synthase Type II ,Nitric Oxide Synthase Type I ,urologic and male genital diseases ,albuminuria ,Nitric oxide ,chemistry.chemical_compound ,plasma renin activity ,Isoantibodies ,Internal medicine ,medicine ,Animals ,RNA, Messenger ,mesangioproliferative glomerulonephritis ,endothelial nitric oxide synthase ,Nephritis ,biology ,business.industry ,urogenital system ,Glomerulosclerosis ,Glomerulonephritis ,medicine.disease ,Rats ,macrophages ,Nitric oxide synthase ,Endocrinology ,chemistry ,Rats, Inbred Lew ,Nephrology ,Acute Disease ,Chronic Disease ,biology.protein ,Albuminuria ,Mesangial proliferative glomerulonephritis ,Nitric Oxide Synthase ,medicine.symptom ,business ,Kidney disease - Abstract
Nitric oxide synthase isoform expression in acute versus chronic anti-Thy 1 nephritis.BackgroundTwo inbred Lewis rat substrains (LEW/Moe, LEW/Maa) were identified responding differently to induction of anti-Thy 1 glomerulonephritis (aThy 1-GN). LEW/Moe rats show an acute mesangioproliferative glomerulonephritis with rapid healing of glomerular lesions within four weeks, while LEW/Maa rats develop severe glomerular injury followed by chronic glomerular sclerosis and persistent albuminuria. We investigated whether the glomerular expression pattern of nitric oxide synthase (NOS) isoforms could explain these substrain-related differences.MethodsRats (N = 5 to 7 per group) were investigated in a time course experiment. Severity of aThy 1-GN was determined by albuminuria measurements, glomerular matrix score and microaneurysm formation. Glomerular gene expression of NOS isoforms was determined by semiquantitative RT-PCR. Inducible NOS (iNOS) activity was determined in cultured glomeruli and peritoneal macrophages. Neuronal NOS (nNOS) protein expression was detected by Western blotting and enzyme histochemistry. Plasma renin activity (PRA) was measured by RIA.ResultsInduction of iNOS expression and activity was found significantly increased and sustained in LEW/Maa vs. LEW/Moe rats associated with an increased number of infiltrating macrophages and with an increased capacity of iNOS-expression and iNOS-activation by isolated macrophages in LEW/Maa rats. Glomerular nNOS mRNA and nNOS protein expression were constitutively increased in LEW/Maa rats. Renal nNOS localization was restricted to the macula densa region in both substrains and associated with increased PRA in LEW/Maa rats. No difference in glomerular endothelial NOS-mRNA expression between the substrains was observed.ConclusionsIncreased glomerular iNOS and nNOS expression were associated with chronic anti-Thy 1 glomerulonephritis in LEW/Maa rats and may contribute to glomerular damage by separate mechanisms.
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411. Vascular access calcification predicts mortality in hemodialysis patients
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Ralf Westenfeld, Diana C. Grootendorst, Tatjana Damjanovic, Nada Dimkovic, Leon J. Schurgers, Jürgen Floege, Georg Schlieper, Markus Ketteler, Thilo Krüger, Natasa Markovic, Zivka Djuric, Sinisa Dimkovic, Friedo W. Dekker, and Vincent Brandenburg
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medicine.medical_specialty ,hemodialysis patients ,medicine.medical_treatment ,Arteriovenous fistula ,Logistic regression ,Catheterization ,AV fistula ,Predictive Value of Tests ,Renal Dialysis ,Risk Factors ,Internal medicine ,Diabetes mellitus ,medicine ,Humans ,Risk factor ,calcification inhibitors ,Dialysis ,Aged ,Analysis of Variance ,Proportional hazards model ,business.industry ,Calcinosis ,Middle Aged ,medicine.disease ,mortality ,Nephrology ,vascular calcification ,Cardiology ,Kidney Failure, Chronic ,Hemodialysis ,business ,Calcification - Abstract
Vascular calcification is a recognized risk factor for cardiovascular mortality in patients with end-stage renal disease. The aim of this study was to identify risk factors for vascular access calcification and to determine if patients with this disorder are at increased risk of death. Vascular access calcification was found in 49 of 212 hemodialysis patients as measured by plain X-ray (arteriovenous fistula or synthetic graft) in two dimensions. Male gender, diabetes mellitus, and length of time on dialysis were independent predictors for access calcification determined by logistic regression multivariate analysis. Serum parameters were not independently related to access calcification. Kaplan-Meier analysis showed an increased mortality risk, and Cox regression analysis confirmed that vascular access calcification was an independent mortality predictor. Our study suggests that detection of vascular access calcification is a cost-effective method to identify patients at increased mortality risk.
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412. Deficiencies of calcium-regulatory proteins in dialysis patients: A novel concept of cardiovascular calcification in uremia
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Ralf Westenfeld, Philipp Bongartz, Markus Ketteler, Cees Vermeer, Willi Jahnen-Dechent, Thomas Metzger, Jürgen Floege, Christoph Wanner, Ulrich Gladziwa, and Leon J. Schurgers
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medicine.medical_specialty ,Population ,calcium-regulatory proteins ,Pathogenesis ,Hyperphosphatemia ,uremia ,Cardiovascular calcification ,Renal Dialysis ,Internal medicine ,Matrix gla protein ,Animals ,Humans ,Medicine ,cardiovascular calcification ,education ,AHSG/Fetuin ,Extracellular Matrix Proteins ,education.field_of_study ,biology ,business.industry ,Calcium-Binding Proteins ,Calcinosis ,MGP ,medicine.disease ,Fetuin ,Uremia ,Endocrinology ,Cardiovascular Diseases ,Nephrology ,biology.protein ,Kidney Failure, Chronic ,Calcium ,business ,Calcification - Abstract
Deficiencies of calcium-regulatory proteins in dialysis patients: A novel concept of cardiovascular calcification in uremia. Dialysis patients suffer a manifold increase in cardiovascular mortality when compared to a nonuremic population, while this phenomenon is not sufficiently explained by an increased prevalence of traditional risk factors, such as hypercholesterolemia and hypertension. The presence of hyperphosphatemia, of an increased calcium x phosphate product, as well as the magnitude of vascular and valvular calcifications, were recently identified as specific major risk factors of cardiovascular mortality in the uremic population. Furthermore, hyperphosphatemia and an increased calcium x phosphate product could be quantitatively linked to the burden of coronary artery calcification in young dialysis patients, suggesting the correction of hyperphosphatemia as the central target for preventive therapeutic intervention. Recent studies in knockout mice, however, point to the alternative possibility that deficiencies in calcium-regulatory proteins may represent important pathomechanisms leading to extraosseous calcifications. α 2 -Heremans Schmid glycoprotein (Ahsg/fetuin) and matrix Gla protein (MGP) are strong inhibitors of calcification in vivo. Novel evidence that deficiencies of such proteins may be involved in the pathogenesis of cardiovascular calcifications in dialysis patients will be discussed.
413. Selective cyclooxygenase-2 inhibition impairs glomerular capillary healing in experimental glomerulonephritis
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Uta Kunter, Frank Eitner, Ulf Janssen, Katsuyuki Matsui, Ralf Westenfeld, Tammo Ostendorf, Masashi Kitahara, Jürgen Floege, and Dontscho Kerjaschki
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medicine.medical_specialty ,Glomerulonephritis, Membranoproliferative ,Renal glomerulus ,urologic and male genital diseases ,Statistics, Nonparametric ,Immunoenzyme Techniques ,Lactones ,Type IV collagen ,Internal medicine ,medicine ,Animals ,Cyclooxygenase Inhibitors ,Sulfones ,Rofecoxib ,Sulfonamides ,Kidney ,biology ,business.industry ,Hemodynamics ,Glomerulonephritis ,General Medicine ,medicine.disease ,Glomerular Mesangium ,Rats ,Microscopy, Electron ,medicine.anatomical_structure ,Endocrinology ,Mesangiolysis ,Celecoxib ,Nephrology ,biology.protein ,Albuminuria ,Pyrazoles ,Cyclooxygenase ,medicine.symptom ,business ,medicine.drug - Abstract
Selective cyclooxygenase-2 (COX-2) inhibitors have anti-inflammatory activity and reduce proteinuria in experimental membranous glomerulonephritis. Antiangiogenic properties of COX-2 inhibitors were recently reported. Whether these properties are relevant to the glomerular healing process in inflammatory glomerular diseases was investigated. For evaluation of the effects of selective COX-2 inhibitors on the glomerular healing process in a rat model of mesangioproliferative glomerulonephritis (induced by anti-Thy 1.1 antibody), a selective COX-2 inhibitor (rofecoxib or celecoxib) or vehicle was administered daily from day 1 after disease induction until euthanasia on day 6. Additional nephritic rats were treated with rofecoxib or vehicle from day 1 to day 10 and were monitored until day 28. Selective COX-2 inhibition led to significant increases in mesangiolysis (up to +71%) on days 2 and 6 and in albuminuria (up to 3.1-fold) on day 6. This augmentation of glomerular capillary damage was associated with rarefaction of glomerular endothelial cells, whereas the proliferation and activation of mesangial cells were not affected. No significant effects on the glomerular influx of polymorphonuclear neutrophils or the infiltration and proliferation of monocytes/macrophages at day 2 were noted. These effects were independent of systemic hemodynamic features, because rofecoxib did not affect systolic BP on day 2 or 5. Nephritic rats treated with rofecoxib for 10 d demonstrated persistent glomerular injury at day 28, as indicated by increased albuminuria (10-fold) and mesangial type IV collagen deposition (+24%). In normal rats, 5-d administration of rofecoxib failed to induce albuminuria or morphologic renal damage. In conclusion, selective COX-2 inhibitors impair glomerular capillary repair after mesangiolysis in rats with anti-Thy 1.1 glomerulonephritis. These data suggest that selective COX-2 inhibitors should be used with caution among patients with inflammatory endocapillary glomerular disorders.
414. Liver function during mechanical circulatory support: from witness to prognostic determinant
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Ralf Westenfeld, Christian Jung, and Malte Kelm
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,030204 cardiovascular system & hematology ,Critical Care and Intensive Care Medicine ,Extracorporeal ,03 medical and health sciences ,0302 clinical medicine ,Extracorporeal Membrane Oxygenation ,Liver Function Tests ,Diabetes mellitus ,medicine ,Extracorporeal membrane oxygenation ,Humans ,Intensive care medicine ,Heart Failure ,medicine.diagnostic_test ,business.industry ,030208 emergency & critical care medicine ,medicine.disease ,Prognosis ,Liver ,Life support ,Heart failure ,Circulatory system ,Commentary ,Female ,Liver function ,Liver function tests ,business - Abstract
In recent years, the treatment options for patients with severe cardiorespiratory failure have been extended by the implementation of mechanical circulatory support (MCS). Identification of patients that benefit most from this cost-intensive treatment modality is of central importance, but is also challenging. Previous studies unravelled certain patient characteristics that should be taken into account, such as age, weight, and underlying pathology, and also the delay until MCS implementation as well as tissue hypoxia as prognostic factors. Relevant comorbidities included neurologic, renal, and hepatic disorders. Of note, baseline liver function tests predicted outcome in patients on extracorporeal life support (ECLS), including short-term and long-term mortality. Most strikingly, increased levels of alkaline phosphatase and total bilirubin indicated unfavourable short-term and long-term survival even after adjustment for age, gender, left ventricular function, and relevant known comorbidities such as impaired renal function and diabetes. Therefore, the assessment of liver function tests may be regarded as another piece in the complex puzzle of our efforts perceiving the ideal ECLS candidate with positive long-term outcome.
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415. T2-Mapping CMR increases the diagnostic sensitivity for detection of myocardial inflammation in patients with possible myocarditis - a prospective endomyocardial biopsy-controlled study
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Patrick J. Horn, B. Stanske, Ulrich Flögel, Florian Bönner, Maximilian Spieker, Malte Kelm, Mirja Neizel-Wittke, Sebastian M. Haberkorn, Ralf Westenfeld, Britta Butzbach, and Felix T Range
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Medicine(all) ,medicine.medical_specialty ,Ejection fraction ,Myocarditis ,Radiological and Ultrasound Technology ,business.industry ,T2 mapping ,H&E stain ,Dilated cardiomyopathy ,medicine.disease ,Sudden cardiac death ,Endomyocardial biopsy ,Internal medicine ,Poster Presentation ,medicine ,Cardiology ,cardiovascular system ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Cardiology and Cardiovascular Medicine ,business ,Angiology - Abstract
Myocarditis has been reported in up to 20% of sudden cardiac death in young adults and is a frequent precursor of dilated cardiomyopathy. Unfortunately, the diagnostic tools for detection of myocarditis are still imperfect: Sensitivity of endomyocardial biopsy (EMB) is reduced largely due to the inherent sampling error. Cardiac magnetic resonance (CMR) offers the advantage of analysing the whole myocardium, but contrast-enhanced as well as T2weighted CMR exhibit inadequate sensitivity, especially during early stages of inflammation. Our hypothesis was that quantitative T2 relaxation mapping increases diagnostic sensitivity in CMR-based diagnosis of myocarditis. Methods We carried out a prospective observational study in patients with probable acute myocarditis characterized by clinical presentation, new global or regional wall abnormalities or arrhythmias or hsTNT-elevation. Of the 55 patients screened, two patients did not undergo CMR (1 pacemaker, 1 ECLS-support) and 16 patients refused EMB. The remaining 37 patients underwent EMB and CMR examination (1.5 T, Archieva, Philips) within 36h. Histological evaluation was performed by two independent pathologists (hematoxylin eosin staining, picrosirius red, IH CD68, CD45R0 and CD3) and by molecular analysis for viral replication/genome. CMR data were analysed blinded with respect to ventricular volumes and ejection fraction as well as T2, LGE and Strain Encoded (SENC)Imaging. A GRASE sequence (15 Echoes separated by 10ms, res: 2x2x10 mm2, 3 short axis slices) was used for localized T2 mapping. Age-matched volunteers (37) served as controls for ROC curve analysis in terms of quantitative T2-mapping. Results were compared by two-sided t-Test; p
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416. Predictors of low circulating endothelial progenitor cell numbers in haemodialysis patients.
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Georg Schlieper, Mihail Hristov, Vincent Brandenburg, Thilo Krüger, Ralf Westenfeld, Andreas H. Mahnken, Eray Yagmur, Georg Boecker, Nicole Heussen, Ulrich Gladziwa, Markus Ketteler, Christian Weber, and Jürgen Floege
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HEMODIALYSIS patients ,CHRONIC kidney failure ,CARDIOVASCULAR disease related mortality ,KIDNEY diseases ,CALCIFICATION ,FLOW cytometry ,CORONARY arteries ,PATIENTS - Abstract
Background. End-stage renal disease (ESRD) patients exhibit increased cardiovascular mortality associated with cardiovascular calcifications and endothelial dysfunction. As circulating endothelial progenitor cells (EPCs) harbour vascular regenerative potential and are altered in uraemia, we examined clinical and biochemical factors influencing EPC levels as well as the relation between EPC numbers and function and uraemic cardiovascular calcifications. Methods. Sixty-five haemodialysis patients were investigated. Cardiovascular calcifications were assessed by multi-slice spiral CT (MSCT, n = 44) with the calculation of coronary Agatston scores and indirectly by carotid-femoral pulse wave velocity (PWV, n = 61). EPCs were quantified in peripheral blood (CD34+/KDR+) and at day 7 after ex vivo cultivation (ac-LDL+/lectin+) by flow cytometry. In addition, colony-forming units (CFUs), migratory activity, adhesion and viability of isolated EPCs were analysed. Results. EPC numbers were reduced (P < 0.001) compared to 27 healthy controls (−64%) or 81 patients with documented coronary artery disease and normal renal function (−58%). Coronary calcifications did not exhibit a significant association with the numbers of circulating CD34+/KDR+ or isolated ac-LDL+/lectin+ EPCs. No difference in EPC functions was observed between the 10 patients with the lowest Agatston scores (range 0–41) versus those with the highest scores (range 1181–3736). Multivariate analysis revealed low fetuin-A serum levels to be a positive predictor, while haematocrit and reticulocytes were negative predictors of reduced ac-LDL+/lectin+ EPC numbers. Conclusions. EPC numbers and function did not correlate with the degree of coronary calcifications in haemodialysis patients. Rather they appear to be related to serum fetuin-A levels, haematocrit and reticulocytes. [ABSTRACT FROM AUTHOR]
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- 2008
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417. Fetuin-A (AHSG) prevents extraosseous calcification induced by uraemia and phosphate challenge in mice.
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Ralf Westenfeld, Cora Schäfer, Ralf Smeets, Vincent M. Brandenburg, Jürgen Floege, Markus Ketteler, and Willi Jahnen-Dechent
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KIDNEY diseases , *ALPHA fetoproteins , *CALCIFICATION , *BIOMINERALIZATION - Abstract
Background. Chronic kidney disease (CKD) is associated with vascular and tissue calcification. The extent of vascular calcification has been identified as an independent risk factor of cardiovascular death in patients on haemodialysis. Methods. We studied the role of fetuin-A in CKD-associated calcification using a mouse model of graded renal insufficiency generated by nephrectomy and high phosphate diet. We used wild-type and fetuin-A-deficient mice on the calcification resistant genetic background C57BL/6 to study the influence on calcification of CKD, dietary phosphate and fetuin deficiency. Hyperphosphataemia, elevated BUN, hyperparathyroidism and von Kossa histochemistry served as indicators of calcification disease. The expression of osteopontin, a marker of osteoblast-like cell differentiation was analyzed by realtime PCR and immunohistechemistry. Results. We detected tissue and genotype-specific susceptibility for calcification. Fetuin-A-deficient mice with CKD and high phosphate diet had only a moderately elevated serum calcium phosphate product (6.9â±â1.4âmmol2/l2), but suffered severe calcification of kidney, heart and lung. In contrast, wild-type mice under the same conditions developed renal calcinosis only despite an elevated serum calcium phosphate product (9.6â±â0.9âmmol2/l2). Calcification was preceded by the local induction of osteopontin, a marker for osteoblast-like cell differentiation. Conclusion. Fetuin-A deficiency, CKD and high phosphate diet act synergistically in the pathogenesis of extraosseous calcification. [ABSTRACT FROM AUTHOR]
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- 2007
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418. Optimal C-arm angulation during transcatheter aortic valve replacement: Accuracy of a rotational C-arm computed tomography based three dimensional heart model.
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Veulemans V, Mollus S, Saalbach A, Pietsch M, Hellhammer K, Zeus T, Westenfeld R, Weese J, Kelm M, and Balzer J
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Aim: To investigate the accuracy of a rotational C-arm CT-based 3D heart model to predict an optimal C-arm configuration during transcatheter aortic valve replacement (TAVR)., Methods: Rotational C-arm CT (RCT) under rapid ventricular pacing was performed in 57 consecutive patients with severe aortic stenosis as part of the pre-procedural cardiac catheterization. With prototype software each RCT data set was segmented using a 3D heart model. From that the line of perpendicularity curve was obtained that generates a perpendicular view of the aortic annulus according to the right-cusp rule. To evaluate the accuracy of a model-based overlay we compared model- and expert-derived aortic root diameters., Results: For all 57 patients in the RCT cohort diameter measurements were obtained from two independent operators and were compared to the model-based measurements. The inter-observer variability was measured to be in the range of 0°-12.96° of angular C-arm displacement for two independent operators. The model-to-operator agreement was 0°-13.82°. The model-based and expert measurements of aortic root diameters evaluated at the aortic annulus ( r = 0.79, P < 0.01), the aortic sinus ( r = 0.93, P < 0.01) and the sino-tubular junction ( r = 0.92, P < 0.01) correlated on a high level and the Bland-Altman analysis showed good agreement. The interobserver measurements did not show a significant bias., Conclusion: Automatic segmentation of the aortic root using an anatomical model can accurately predict an optimal C-arm configuration, potentially simplifying current clinical workflows before and during TAVR., Competing Interests: Conflict-of-interest statement: Tobias Z and Verena V receive honoraria from St. Jude Medical for lectures. Philips Healthcare and the University Hospital Duesseldorf have a master research agreement. All authors take responsibility for all aspects of the reliability and freedom from bias of the data presented and their discussed interpretation.
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- 2016
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419. Red cell distribution width in anemic patients undergoing transcatheter aortic valve implantation.
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Hellhammer K, Zeus T, Verde PE, Veulemanns V, Kahlstadt L, Wolff G, Erkens R, Westenfeld R, Navarese EP, Merx MW, Rassaf T, and Kelm M
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Aim: To determine the impact of red blood cell distribution width on outcome in anemic patients undergoing transcatheter aortic valve implantation (TAVI)., Methods: In a retrospective single center cohort study we determined the impact of baseline red cell distribution width (RDW) and anemia on outcome in 376 patients with aortic stenosis undergoing TAVI. All patients were discussed in the institutional heart team and declined for surgical aortic valve replacement due to high operative risk. Collected data included patient characteristics, imaging findings, periprocedural in hospital data, laboratory results and follow up data. Blood samples for hematology and biochemistry analysis were taken from every patient before and at fixed intervals up to 72 h after TAVI including blood count and creatinine. Descriptive statistics were used for patient's characteristics. Kaplan-Meier survival curves were used for time to event outcomes. A recursive partitioning regression and classification was used to investigate the association between potential risk factors and outcome variables., Results: Mean age in our study population was 81 ± 6.1 years. Anemia was prevalent in 63.6% (n = 239) of our patients. Age and creatinine were identified as risk factors for anemia. In our study population, anemia per se did influence 30-d mortality but did not predict longterm mortality. In contrast, a RDW > 14% showed to be highly predictable for a reduced short- and longterm survival in patients with aortic valve disease after TAVI procedure., Conclusion: Age and kidney function determine the degree of anemia. The anisocytosis of red blood cells in anemic patients supplements prognostic information in addition to that derived from the WHO-based definition of anemia.
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- 2016
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