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Buhl M, Kloskowski T, Jundzill A, Szeliski K, Rasmus M, Dąbrowski P, Siedlecka N, Drewa T, Pokrywczynska M. Increased Expression of p63 Protein and Sonic Hedgehog Signaling Molecule in Buccal Epithelial Holoclones. Stem Cells Dev 2021; 30:1037-1048. [PMID: 34486385 DOI: 10.1089/scd.2021.0190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Construction of many tissues and organs de novo requires the use of external epithelial cell sources. In the present study, we optimized the isolation, expansion, and characterization of porcine oral epithelial cells from buccal tissue (Buccal Epithelial Cells, BECs). Additionally, we tested whether key markers [cytokeratin 14 (ck14), p63 protein, and sonic hedgehog molecule (shh)] expression profiles are correlated with three buccal epithelial clone types. Two digestion methods of BECs isolation [Method 1, M1 (collagenase IV/dispase and accutase) and Method 2, M2 (collagenase IV/dispase and trypsin/EDTA)] were compared. Cells obtained by more effective method were further cultured to the third passage and analyzed. Holoclone-, meroclone-, and paraclone-like colonies were identified based on BEC morphology. Immunofluorescent staining was performed to compare selected markers for the indicated buccal clone types. Comparative analysis demonstrated the advantage of isolation using M1 over M2. Cells from the third passage exhibited average 92.73% ± 2.27% presence of ck14. Real-time polymerase chain reaction confirmed expression of tested genes [cytokeratin 8 (ck8), ck14, integrin β1, and p63]. The highest level of ck14, shh and p63, was observed for holoclones. The comparable ck14 expression was observed in the mero- and paraclones. Meroclones expressed significantly lower levels of shh compared with paraclones. The weakest p63 expression was observed in the paraclone-like cells. It was demonstrated that holoclones are the richest in shh (+) and p63 (+) stem cells and these cells should appear to be a promising alternative for obtaining epithelial cells for tissue engineering purposes.
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Affiliation(s)
- Monika Buhl
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Tomasz Kloskowski
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Arkadiusz Jundzill
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland.,Department of Plastic, Reconstructive, and Esthetic Surgery, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Kamil Szeliski
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Marta Rasmus
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Paweł Dąbrowski
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Natalia Siedlecka
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Tomasz Drewa
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Marta Pokrywczynska
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
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Pokrywczynska M, Jundzill A, Tworkiewicz J, Buhl M, Balcerczyk D, Adamowicz J, Kloskowski T, Rasmus M, Mecinska-Jundzill K, Kasinski D, Frontczak-Baniewicz M, Holysz M, Skopinska-Wisniewska J, Bodnar M, Marszalek A, Antosik P, Grzanka D, Drewa T. Urinary bladder augmentation with acellular biologic scaffold-A preclinical study in a large animal model. J Biomed Mater Res B Appl Biomater 2021; 110:438-449. [PMID: 34323358 DOI: 10.1002/jbm.b.34920] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 07/05/2021] [Accepted: 07/18/2021] [Indexed: 12/12/2022]
Abstract
Current strategies in urinary bladder augmentation include use of gastrointestinal segments, however, the technique is associated with inevitable complications. An acellular biologic scaffold seems to be a promising option for urinary bladder augmentation. The aim of this study was to evaluate the utility of bladder acellular matrix (BAM) for reconstruction of clinically significant large urinary bladder wall defects in a long-term porcine model. Urinary bladders were harvested from 10 pig donors. Biological scaffolds were prepared by chemically removing all cellular components from urinary bladder tissue. A total of 10 female pigs underwent hemicystectomy and subsequent bladder reconstruction with BAM. The follow-up study was 6 months. Reconstructed bladders were subjected to radiological, macroscopic, histological, immunohistochemical, and molecular evaluations. Six out of ten animals survived the 6-month follow-up period. Four pigs died during observation due to mechanical failure of the scaffold, anastomotic dehiscence between the scaffold and native bladder tissue, or occluded catheter. Tissue engineered bladder function was normal without any signs of postvoid residual urine in the bladder or upper urinary tracts. Macroscopically, graft shrinkage was observed. Urothelium completely covered the luminal surface of the graft. Smooth muscle regeneration was observed mainly in the peripheral graft region and gradually decreased toward the center of the graft. Expression of urothelial, smooth muscle, blood vessel, and nerve markers were lower in the reconstructed bladder wall compared to the native bladder. BAM seems to be a promising biomaterial for reconstruction of large urinary bladder wall defects. Further research on cell-seeded BAM to enhance urinary bladder regeneration is required.
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Affiliation(s)
- Marta Pokrywczynska
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Arkadiusz Jundzill
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Jakub Tworkiewicz
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Monika Buhl
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Daria Balcerczyk
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Jan Adamowicz
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Tomasz Kloskowski
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Marta Rasmus
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Kaja Mecinska-Jundzill
- Department of Dermatology, Sexually Transmitted Diseases and Immunodermatology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Damian Kasinski
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | | | - Marcin Holysz
- Department of Biochemistry and Molecular Biology, K. Marcinkowski University of Medical Sciences, Poznan, Poland
| | | | - Magdalena Bodnar
- Department of Clinical Pathomorphology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Andrzej Marszalek
- Department of Tumor Pathology, Center of Oncology, Poznan University of Medical Sciences, Poznan, Poland
| | - Paulina Antosik
- Department of Clinical Pathomorphology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Dariusz Grzanka
- Department of Clinical Pathomorphology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
| | - Tomasz Drewa
- Chair of Urology and Andrology, Department of Regenerative Medicine, Cell and Tissue Bank, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Bydgoszcz, Poland
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Pokrywczynska M, Maj M, Kloskowski T, Buhl M, Balcerczyk D, Jundziłł A, Szeliski K, Rasmus M, Drewa T. Molecular Aspects of Adipose-Derived Stromal Cell Senescence in a Long-Term Culture: A Potential Role of Inflammatory Pathways. Cell Transplant 2021; 29:963689720917341. [PMID: 32314614 PMCID: PMC7586277 DOI: 10.1177/0963689720917341] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Long-term culture of mesenchymal stromal/stem cells in vitro leads to their senescence. It is very important to define the maximal passage to which the mesenchymal stromal/stem cells maintain their regenerative properties and can be used for cellular therapies and construction of neo-organs for clinical application. Adipose-derived stromal/stem cells were isolated from porcine adipose tissue. Immunophenotype, population doubling time, viability using bromodeoxyuridine assay, MTT assay, clonogencity, β-galactosidase activity, specific senescence-associated gene expression, apoptosis, and cell cycle of adipose-derived mesenchymal stromal/stem cells (AD-MSCs) were analyzed. All analyses were performed through 12 passages (P). Decreasing viability and proliferative potential of AD-MSCs with subsequent passages together with prolonged population doubling time were observed. Expression of β-galactosidase gradually increased after P6. Differentiation potential of AD-MSCs into adipogenic, chondrogenic, and osteogenic lineages decreased at the end of culture (P10). No changes in the cell cycle, the number of apoptotic cells and expression of specific AD-MSC markers during the long-term culture were revealed. Molecular analysis showed increased expression of genes involved in activation of inflammatory response. AD-MSCs can be cultured for in vivo applications without loss of their properties up to P6.
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Affiliation(s)
- Marta Pokrywczynska
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland.,Both the authors contributed equally to this article
| | - Małgorzata Maj
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland.,Department of Tissue Engineering, Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland.,Both the authors contributed equally to this article
| | - Tomasz Kloskowski
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Monika Buhl
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Daria Balcerczyk
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Arkadiusz Jundziłł
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland.,Department of Plastic, Reconstructive and Aesthetic Surgery, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Kamil Szeliski
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Marta Rasmus
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Tomasz Drewa
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland.,Department of Tissue Engineering, Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
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Adamowicz J, Kloskowski T, Stopel M, Gniadek M, Rasmus M, Balcerczyk D, Buhl M, Gagat M, Antosik P, Grzanka D, Sionkowska A, Drewa T, Pokrywczynska M. The development of marine biomaterial derived from decellularized squid mantle for potential application as tissue engineered urinary conduit. Mater Sci Eng C Mater Biol Appl 2020; 119:111579. [PMID: 33321625 DOI: 10.1016/j.msec.2020.111579] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/12/2020] [Accepted: 09/24/2020] [Indexed: 11/26/2022]
Abstract
Tissue engineering is focusing research effort on search for new biomaterials that might be applied to create artificial urinary conduit. Nevertheless, the demanding biomechanical characteristics necessary for proper conduit function is difficult to be replicated. In this study, we are introducing novel marine biomaterial obtained by decellularization of squid mantle derived from Loligo vulgaris. Squid mantles underwent decellularization according to developed dynamic flow two-staged procedure. Efficacy of the method was confirmed by computational dynamic flow analysis. Subsequently Decellularized Squid Mantle (DSM) underwent extensive histological analysis and mechanical evaluation. Based on gained biomechanical data the computational modelling using finite element method was utilized to simulate behavior of DSM used as a urinary conduit. Taking into account potential application in reconstructive urology, the DSM was then evaluated as a scaffold for urothelial and smooth muscle cells derived from porcine urinary bladder. Conducted analysis showed that DSM created favorable environment for cells growth. In addition, due to polarized structure and natural external polysaccharide layer, it protected seeded cells from urine.
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Affiliation(s)
- J Adamowicz
- Chair of Urology, Department of Regenerative Medicine, Collegium Medicum, Nicolaus Copernicus University, Curie-Skłodowskiej 9, 85-094 Bydgoszcz, Poland; Reconstructive Urology Working Group, Young Academic Urologists, European Association of Urology, the Netherlands.
| | - T Kloskowski
- Chair of Urology, Department of Regenerative Medicine, Collegium Medicum, Nicolaus Copernicus University, Curie-Skłodowskiej 9, 85-094 Bydgoszcz, Poland
| | - M Stopel
- Department of Mechanics and Computer Methods, University of Science and Technology, Kaliskiego 7, 85-796 Bydgoszcz, Poland
| | - M Gniadek
- Department of Fundamentals of Machine Design and Biomedical Engineering, University of Science and Technology, Kaliskiego 7, 85-796 Bydgoszcz, Poland
| | - M Rasmus
- Chair of Urology, Department of Regenerative Medicine, Collegium Medicum, Nicolaus Copernicus University, Curie-Skłodowskiej 9, 85-094 Bydgoszcz, Poland
| | - D Balcerczyk
- Chair of Urology, Department of Regenerative Medicine, Collegium Medicum, Nicolaus Copernicus University, Curie-Skłodowskiej 9, 85-094 Bydgoszcz, Poland
| | - M Buhl
- Chair of Urology, Department of Regenerative Medicine, Collegium Medicum, Nicolaus Copernicus University, Curie-Skłodowskiej 9, 85-094 Bydgoszcz, Poland
| | - M Gagat
- Department of Histology and Embryology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz Curie-Skłodowskiej 9, 85-094 Bydgoszcz, Poland
| | - P Antosik
- Department of Clinical Pathomorphology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz Curie-Skłodowskiej 9, 85-094 Bydgoszcz, Poland
| | - D Grzanka
- Department of Clinical Pathomorphology, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz Curie-Skłodowskiej 9, 85-094 Bydgoszcz, Poland
| | - A Sionkowska
- Department of Chemistry of Biomaterials and Cosmetics, Nicolaus Copernicus University, Gagarina 11, 87-100 Torun, Poland
| | - T Drewa
- Chair of Urology, Department of Regenerative Medicine, Collegium Medicum, Nicolaus Copernicus University, Curie-Skłodowskiej 9, 85-094 Bydgoszcz, Poland
| | - M Pokrywczynska
- Chair of Urology, Department of Regenerative Medicine, Collegium Medicum, Nicolaus Copernicus University, Curie-Skłodowskiej 9, 85-094 Bydgoszcz, Poland
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Konowalczyk S, Buhl M, Moon J, Mello ZR. THE PAST, PRESENT, AND FUTURE ALL MATTER: HOW TIME PERSPECTIVE IS ASSOCIATED WITH OPTIMISM AND SENSATION SEEKING AMONG YOUNG ADULTS. Research in Human Development 2019. [DOI: 10.1080/15427609.2019.1662709] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Buhl M, Kloskowski T, Jundzill A, Gagat M, Balcerczyk D, Adamowicz J, Grzanka A, Nowacki M, Drewa G, Olszewska-Słonina D, Drewa T, Pokrywczynska M. The different expression of key markers on urothelial holoclonal, meroclonal, and paraclonal cells in in vitro culture. Cell Biol Int 2019; 43:456-465. [PMID: 30729622 DOI: 10.1002/cbin.11109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 02/02/2019] [Indexed: 12/13/2022]
Abstract
Urothelial cell populations which differ in morphology and proliferation capacities can be isolated from the urinary bladder. The goal of this study was to analyze a clonal, proliferative, and self-renewing potential of porcine urothelial cells and to compare expression of selected adhesion and tight junction molecules, urothelial and stem cell markers for the urothelial clone types. Urothelial cells were isolated from 10 porcine urinary bladders. Three different clone types: holoclone-, meroclone-and paraclone-like colonies were identified based on their morphology. To characterize and compare the urothelial clones the immunofluorescent stains were performed. Expression of pancytokeratin (PanCK), Ki-67 and p63 was higher for holoclone- like cells compared to meroclone-and paraclone-like cells (P < 0.05). Meroclone-like cells expressed higher levels of p63 compared to paraclone- like cells (P < 0.05). The level of Ki-67 and PanCK for meroclone- and paraclone- like cells was comparable (P > 0.05). β1 and β4 integrins were not expressed. Expression of zonula occludens-1 (ZO-1) in cell-cell junctions for paraclone-, meroclone-and holoclone-like cells was 17.6 ± 0.6, 14.7 ± 0.5, and 16.1 ± 0.4, respectively. The results of actin filaments (F-actin) expression were 253,634 ± 6,920 for meroclone-like cells, 198,512 ± 7,977 for paraclone-like cells and 133,544 ± 3,169 for holoclone-like cells. Three urothelial cell types with differing features can be isolated from the bladder. Holoclone-like cells are the richest in stem cells and should be used in further studies for construction of neo-bladder or neo-conduit using tissue engineering methods.
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Affiliation(s)
- Monika Buhl
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Poland
| | - Tomasz Kloskowski
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Poland
| | - Arkadiusz Jundzill
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Poland
| | - Maciej Gagat
- Department of Embriology and Histology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Poland
| | - Daria Balcerczyk
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Poland
| | - Jan Adamowicz
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Poland
| | - Alina Grzanka
- Department of Embriology and Histology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Poland
| | - Maciej Nowacki
- Chair and Department of Surgical Oncology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Poland
| | | | - Dorota Olszewska-Słonina
- Department of Pathobiochemistry and Clinical Chemistry, Nicolaus Copernicus University University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Poland
| | - Tomasz Drewa
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Poland
| | - Marta Pokrywczynska
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Poland
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Pokrywczynska M, Jundzill A, Rasmus M, Adamowicz J, Balcerczyk D, Buhl M, Warda K, Buchholz L, Gagat M, Grzanka D, Drewa T. Understanding the role of mesenchymal stem cells in urinary bladder regeneration-a preclinical study on a porcine model. Stem Cell Res Ther 2018; 9:328. [PMID: 30486856 PMCID: PMC6260700 DOI: 10.1186/s13287-018-1070-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 10/20/2018] [Accepted: 11/08/2018] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The tissue engineering of urinary bladder advances rapidly reflecting clinical need for a new kind of therapeutic solution for patients requiring urinary bladder replacement. Majority of the bladder augmentation studies have been performed in small rodent or rabbit models. Insufficient number of studies examining regenerative capacity of tissue-engineered graft in urinary bladder augmentation in a large animal model does not allow for successful translation of this technology to the clinical setting. The aim of this study was to evaluate the role of adipose-derived stem cells (ADSCs) in regeneration of clinically significant urinary bladder wall defect in a large animal model. METHODS ADSCs isolated from a superficial abdominal Camper's fascia were labeled with PKH-26 tracking dye and subsequently seeded into bladder acellular matrix (BAM) grafts. Pigs underwent hemicystectomy followed by augmentation cystoplasty with BAM only (n = 10) or BAM seeded with autologous ADSCs (n = 10). Reconstructed bladders were subjected to macroscopic, histological, immunofluoresence, molecular, and radiological evaluations at 3 months post-augmentation. RESULTS Sixteen animals (n = 8 for each group) survived the 3-month follow-up without serious complications. Tissue-engineered bladder function was normal without any signs of post-voiding urine residual in bladders and in the upper urinary tracts. ADSCs enhanced regeneration of tissue-engineered urinary bladder but the process was incomplete in the central graft region. Only a small percentage of implanted ADSCs survived and differentiated into smooth muscle and endothelial cells. CONCLUSIONS The data demonstrate that ADSCs support regeneration of large defects of the urinary bladder wall but the process is incomplete in the central graft region. Stem cells enhance urinary bladder regeneration indirectly through paracrine effect.
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Affiliation(s)
- Marta Pokrywczynska
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Marii Sklodowskiej Curie 9 Street, 85-094 Bydgoszcz, Poland
| | - Arkadiusz Jundzill
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Marii Sklodowskiej Curie 9 Street, 85-094 Bydgoszcz, Poland
| | - Marta Rasmus
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Marii Sklodowskiej Curie 9 Street, 85-094 Bydgoszcz, Poland
| | - Jan Adamowicz
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Marii Sklodowskiej Curie 9 Street, 85-094 Bydgoszcz, Poland
| | - Daria Balcerczyk
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Marii Sklodowskiej Curie 9 Street, 85-094 Bydgoszcz, Poland
| | - Monika Buhl
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Marii Sklodowskiej Curie 9 Street, 85-094 Bydgoszcz, Poland
| | - Karolina Warda
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Marii Sklodowskiej Curie 9 Street, 85-094 Bydgoszcz, Poland
| | - Lukasz Buchholz
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Marii Sklodowskiej Curie 9 Street, 85-094 Bydgoszcz, Poland
| | - Maciej Gagat
- Department of Embryology and Histology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, 85-092 Bydgoszcz, Poland
| | - Dariusz Grzanka
- Department of Clinical Pathomorphology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, 85-094 Bydgoszcz, Poland
| | - Tomasz Drewa
- Department of Regenerative Medicine, Cell and Tissue Bank, Chair of Urology, Nicolaus Copernicus University in Torun, Ludwik Rydygier Medical College in Bydgoszcz, Marii Sklodowskiej Curie 9 Street, 85-094 Bydgoszcz, Poland
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Pokrywczyńska M, Kloskowski T, Balcerczyk D, Buhl M, Jundziłł A, Nowacki M, Męcińska‐Jundziłł K, Drewa T. Stem cells and differentiated cells differ in their sensitivity to urine in vitro. J Cell Biochem 2017; 119:2307-2319. [DOI: 10.1002/jcb.26393] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/30/2017] [Indexed: 11/10/2022]
Affiliation(s)
- Marta Pokrywczyńska
- Chair of Urology, Department of Regenerative Medicine, Cell and Tissue Bank, Ludwik Rydygier's Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland
| | - Tomasz Kloskowski
- Chair of Urology, Department of Regenerative Medicine, Cell and Tissue Bank, Ludwik Rydygier's Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland
| | - Daria Balcerczyk
- Chair of Urology, Department of Regenerative Medicine, Cell and Tissue Bank, Ludwik Rydygier's Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland
| | - Monika Buhl
- Chair of Urology, Department of Regenerative Medicine, Cell and Tissue Bank, Ludwik Rydygier's Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland
| | - Arkadiusz Jundziłł
- Chair of Urology, Department of Regenerative Medicine, Cell and Tissue Bank, Ludwik Rydygier's Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland
- Department of Plastic, Reconstructive and Aesthetic Surgery, Collegium MedicumNicolaus Copernicus UniversityBydgoszczPoland
| | - Maciej Nowacki
- Chair and Department of Surgical Oncology, Ludwik Rydygier's Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in TorunFranciszek Łukaszczyk Memorial HospitalBydgoszczPoland
| | - Kaja Męcińska‐Jundziłł
- Chair of Urology, Department of Regenerative Medicine, Cell and Tissue Bank, Ludwik Rydygier's Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland
| | - Tomasz Drewa
- Chair of Urology, Department of Regenerative Medicine, Cell and Tissue Bank, Ludwik Rydygier's Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland
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9
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Buhl M, Erbe A, Grebing J, Wintz S, Raabe J, Fassbender J. Lateral spin transfer torque induced magnetic switching at room temperature demonstrated by x-ray microscopy. Sci Rep 2013; 3:2945. [PMID: 24126435 PMCID: PMC3796737 DOI: 10.1038/srep02945] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 09/05/2013] [Indexed: 11/29/2022] Open
Abstract
Changing and detecting the orientation of nanomagnetic structures, which can be used for durable information storage, needs to be developed towards true nanoscale dimensions for keeping up the miniaturization speed of modern nanoelectronic components. Therefore, new concepts for controlling the state of nanomagnets are currently in the focus of research in the field of nanoelectronics. Here, we demonstrate reproducible switching of a purely metallic nanopillar placed on a lead that conducts a spin-polarized current at room temperature. Spin diffusion across the metal-metal (Cu to CoFe) interface between the pillar and the lead causes spin accumulation in the pillar, which may then be used to set the magnetic orientation of the pillar. In our experiments, the detection of the magnetic state of the nanopillar is performed by direct imaging via scanning transmission x-ray microscopy (STXM).
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Affiliation(s)
- M Buhl
- 1] Helmholtz-Zentrum Dresden-Rossendorf [2] Technische Universität Dresden
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10
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Gjedsted J, Buhl M, Nielsen S, Schmitz O, Vestergaard ET, Tønnesen E, Møller N. Effects of adrenaline on lactate, glucose, lipid and protein metabolism in the placebo controlled bilaterally perfused human leg. Acta Physiol (Oxf) 2011; 202:641-8. [PMID: 21624100 DOI: 10.1111/j.1748-1716.2011.02316.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIM Adrenaline has widespread metabolic actions, including stimulation of lipolysis and induction of insulin resistance and hyperlactatemia. Systemic adrenaline administration, however, generates a very complex hormonal and metabolic scenario. No studies employing regional, placebo controlled and adrenaline infusion exist. Our study was designed to test the hypothesis that local placebo controlled leg perfusion with adrenaline directly increases local lactate release, stimulates lipolysis, induces insulin resistance and leaves protein metabolism unaffected. METHODS We studied seven healthy volunteers with bilateral femoral vein and artery catheters during 3-h basal and 3-h hyperinsulinemic (0.6 mU kg(-1) min(-1) ) euglycemic clamp conditions. One femoral artery was perfused with saline and the other with adrenaline (0.4 μg min m(-2) ). Lipid metabolism was quantified with [9,10-(3) H] palmitate and amino acid metabolism with (15) N-phenylalanine and lactate and glucose by raw arterio-venous differences. RESULTS Femoral vein plasma adrenaline increased ≈eightfold in the perfused leg with unaltered blood flows. Adrenaline perfusion significantly increased local leg lactate release from 0.01 to 0.25 mmol min(-1) per leg, palmitate release in the basal state 11.5-16.9 μmol min(-1) per leg and during the clamp 2.62-8.44 μmol min(-1) per leg. Glucose uptake decreased during the clamp from ≈180 to 30 μmol min(-1) per leg. Phenylalanine kinetics was not affected by adrenaline. CONCLUSION Adrenaline directly increases lactate release and lipolysis and inhibits insulin-stimulated glucose uptake in the perfused human leg. Adrenaline has no direct effects on peripheral amino acid metabolism. Adrenaline-induced lactate release from striated muscle may be an important mechanism underlying hyperlactatemia in the critically ill.
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Affiliation(s)
- J Gjedsted
- Department of Anaesthesia and Intensive Care Medicine, Aarhus University Hospital, Denmark.
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11
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Loewenhardt B, Rathjen T, Buhl M, Hessmann M, Gries A, Greim C, Manke C, Bernhard M. Strahlenbelastung durch die Ganzkörper-CT in der Polytraumadiagnostik - Einsparpotential durch Lagerungshilfen und -maßnahmen? ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1279135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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12
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Abstract
In this study, the authors report on the development of English and German versions of the Adolescent Time Attitude Scale (ATAS). The ATAS consists of six subscales assessing Past Positive, Past Negative, Present Positive, Present Negative, Future Positive, and Future Negative time attitudes. The authors describe the development of the scales and present data on the reliability and structural validity of ATAS scores in samples of American ( N = 300) and German ( N = 316) adolescents. Internal consistency estimates for scores on the English and German versions of the ATAS were in the .70 to .80 range. Confirmatory factor analyses indicated that a six-factor structure yielded the best fit for scores and that the scores were invariant across samples.
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Affiliation(s)
| | | | - Monika Buhl
- Heidelberg University, Heidelberg, Germany
- German Institute for International Educational Research, Frankfurt, Germany
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13
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Buhl M, Gjedsted J, Granfeldt A, Larsen PØ, Schmitz O, Tønnesen E, Møller N. Metabolic effects of free fatty acids during endotoxaemia in a porcine model--free fatty acid inhibition of growth hormone secretion as a potential catabolic feedback mechanism. Horm Metab Res 2010; 42:348-52. [PMID: 20195947 DOI: 10.1055/s-0030-1248297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Critical illness and severe inflammation are catabolic states characterised by breakdown of tissue and protein stores, by increased levels of free fatty acids, and by insulin resistance. These metabolic features contribute to morbidity and mortality. Growth hormone and insulin are the two major anabolic hormones. The present study was designed to test whether increased levels of free fatty acids (i) inhibit growth hormone secretion and (ii) induce insulin resistance during acute endotoxin exposure in a porcine model of critical illness. We studied 20 pigs for 6 h during combined anaesthesia and endotoxin infusion and a hyperinsulinaemic glucose clamp to control glucose, insulin, and free fatty acid concentrations. Pigs were randomised to two different continuous infusion rates of Intralipid resulting in different, sustained, and elevated free fatty acid concentrations (1.63 mmol l(-1) vs. 0.58 mmol l(-1), p=0.0002). Concomitantly, we observed reduced growth hormone concentrations in the group with high free fatty acid concentrations (3.5 ng ml(-1) vs. 6.6 ng ml(-1), p<0.003). No difference in insulin sensitivity, measured as the glucose infusion rate necessary to maintain euglycaemia, was observed. We conclude that high levels of free fatty acids reduce circulating growth hormone concentrations in porcine endotoxaemia; this probably constitutes a negative feedback mechanism whereby growth hormone induced-stimulation of free fatty acids release inhibit growth hormone secretion. This mechanism may further contribute to protein loss in critical illness. We found no evidence that the increment of plasma free fatty acids between groups contribute to insulin resistance in critical illness.
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Affiliation(s)
- M Buhl
- Medical Department M (Endocrinology and Diabetes), Aarhus University Hospital, Aarhus, Denmark.
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14
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Gjedsted J, Gormsen L, Buhl M, Nørrelund H, Schmitz O, Keiding S, Tønnesen E, Møller N. Forearm and leg amino acid metabolism in the basal state and during combined insulin and amino acid stimulation after a 3-day fast. Acta Physiol (Oxf) 2009; 197:197-205. [PMID: 19508406 DOI: 10.1111/j.1748-1716.2009.02009.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
AIM Fasting is characterized by a progressive loss of protein, but data on protein kinetics are unclear and few have studied the effects of re-feeding. The present study was designed to test the hypothesis that a combined infusion of insulin and amino acids after fasting would induce compensatory increases in protein synthesis and reductions in protein breakdown at the whole body level and in muscle. METHODS We included 10 healthy male volunteers and studied them twice: (1) in the post-absorptive state and (2) after 72 h of fasting. Amino acid kinetics was measured using labelled phenylalanine and tyrosine, whole body energy expenditure was assessed and urea nitrogen synthesis rates were calculated. RESULTS After fasting we observed an increase in arterial blood concentration of branched chain amino acids and a decrease in gluconeogenic amino acids (P < 0.05). Isotopically determined whole body, forearm and leg phenylalanine fluxes were unaltered apart from a 30% decrease in phenylalanine-to-tyrosine conversion (2.0 vs. 1.4 mumol kg(-1) h(-1), P < 0.01). During infusion of insulin and amino acids, amino acid concentrations increased. CONCLUSION Our data indicate that after a 72-h fast basal and insulin/amino acid-stimulated regional phenylalanine fluxes in leg and forearm muscle are unaltered. During fasting concentrations of gluconeogenic amino acids decrease and hepatic and/or renal phenylalanine-to-tyrosine conversion decreases. Thus, as opposed to glucose and lipid metabolism, fasting does not induce insulin resistance as regards amino acid metabolism.
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Affiliation(s)
- J Gjedsted
- Department of Anaesthesia and Intensive Care, Aarhus University Hospital, Aarhus, Denmark.
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15
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Gniewosz B, Noack P, Buhl M. Political alienation in adolescence: Associations with parental role models, parenting styles, and classroom climate. International Journal of Behavioral Development 2009. [DOI: 10.1177/0165025409103137] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The present study examined how parental political attitudes, parenting styles, and classroom characteristics predict adolescents' political alienation, as feelings about the individual's ability to affect the political system's performance at the individual level. Participants were 463 families that included mothers, fathers, and their adolescent children in 6th, 8th, and 10th grades. Teachers reported on the classroom context. Multilevel analyses indicated several findings: parental and adolescent political attitudes supported a parent—adolescent transmission process, adolescents' perceptions of parental attitudes mediated the transmission process, authoritarian parenting style positively predicted adolescent political alienation, and classrooms comprised of teachers with clear educational goals were negatively related to adolescent political alienation. Results are discussed in terms of learning political alienation within family by parent—child transmission. Associations among adolescent political alienation, parenting style, and classroom climate are considered as interaction characteristics with authorities shaping adolescents' political attitudes.
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Affiliation(s)
| | | | - Monika Buhl
- German Institute for International Educational Research,
Germany
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16
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Buhl M, v. Borzeszkowski HH, Chrobok T. Approximate Foldy-Wouthuysen transformation of the Dirac Hamiltonian in general spacetimes. Int J Clin Exp Med 2008. [DOI: 10.1103/physrevd.78.104022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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17
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Rudolph G, Buhl M, Pietschmann M, Priglinger SG, Boergen KP, Kampik A. Frühgeborenen-Retinopathie (ROP). Klinische Aspekte und Ergebnisse nach Dioden-Laserkoagulation. Klin Monbl Augenheilkd 2006. [DOI: 10.1055/s-2006-948244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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18
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Rudolph G, Buhl M, Pietschmann M, Wolf A, Priglinger S, Boergen KP, Kampik A. [Clinical aspects of retinopathy of prematurity. Results following diode laser coagulation]. Klin Monbl Augenheilkd 2006; 223:528-33. [PMID: 16804824 DOI: 10.1055/s-2005-859020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Retinopathy of prematurity (ROP) represents a disease of the immature retina of preterm infants due to irregular vascularisation. The present article gives information about different parameters of the newborns (gestational age, birth weight, need of oxygen, stage of ROP) and shows the results concerning anatomical and functional aspects following diode laser treatment in 61 prematurely born babies, diagnosed and treated in a period of 5S years in the Hospital of the Ludwig Maximilians University. The mean +/- SD gestational age was 24.9 (+/- 1.59) weeks, the mean +/- SD birth weight was 683 (+/- 174) grams. Diode laser treatment was performed at a mean +/- SD age of 36.14 (+/- 2.04) weeks. Stage 3 retinopathy with "plus disease" was diagnosed in 95.5 % of the infants. In comparison to term born babies or preterm infants without ROP, the diode laser-treated newborns showed a higher incidence of myopia (59 %). An unfavourable outcome in term of the anatomic situation was seen in 9.8 % of these babies.
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Affiliation(s)
- G Rudolph
- Augenklinik der Ludwig-Maximilians-Universität, München, Strabismologie, Kinderophthalmologie und Ophthalmogenetik.
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19
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Brakemeier S, Si H, Gollasch M, Höffler D, Buhl M, Köhler R, Hoyer J, Eichler I. Dents disease: identification of a novel mutation in the renal chloride channel CLCN5. Clin Nephrol 2004; 62:387-90. [PMID: 15571186 DOI: 10.5414/cnp62387] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dent's disease is an inherited tubulopathy caused by a mutation in the CLCN5 chloride channel gene. It is characterized by low-molecular weight proteinuria, hypercalciuria, nephrolithiasis or nephrocalcinosis, rickets and eventual-progressive renal failure. Onset of clinical symptoms show a great variability, making a diagnosis at an early stage of the disease often difficult. Given the variably clinical picture, genetic analysis can provide a reliable method to confirm the diagnosis. Here, we report on the case of a patient with progressive renal failure showing signs of a tubular lesion and symptoms of Dent's disease. Although this rare disease was suspected by means of the clinical features, it was genetic analysis that confirmed the diagnosis and revealed a novel mutation in the CLCN5 gene.
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Affiliation(s)
- S Brakemeier
- Department of Nephrology--Charité, Universitätsmedizin Berlin, Germany
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20
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Lewis CT, Abarbanel HD, Kennel MB, Buhl M, Illing L. Synchronization of chaotic oscillations in doped fiber ring lasers. Phys Rev E Stat Nonlin Soft Matter Phys 2001; 63:016215. [PMID: 11304343 DOI: 10.1103/physreve.63.016215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/1999] [Revised: 08/15/2000] [Indexed: 05/23/2023]
Abstract
The synchronization of chaotic rare-earth-doped fiber ring lasers is analyzed. The lasers are first coupled by transmitting a fraction c of the circulating electric field in the transmitter and injecting it into the optical cavity of the receiver. A coupling strategy which relies on modulation of the intensity of the light alone is also examined. Synchronization is studied as a function of the coupling strength, and we see excellent synchronization, even with very small c. We prove that in an open loop configuration (c=1) synchronization is guaranteed due to the particular structure of our equations and of the injection method we use. The generalized synchronization of these model lasers is examined when there is parameter mismatch between the transmitter and receiver lasers. The synchronization is found to be insensitive to a wide range of mismatch in laser parameters, but it is sensitive to other parameters, in particular those associated with the phase and the polarization of the circulating electric field. Communicating information between the transmitter and receiver lasers is also addressed. We investigate a scheme for modulating information onto the chaotic electric field and then demodulating and detecting the information embedded in the chaotic signal passed down the communications channel. We show full recovery with very low error for a wide range of coupling strengths.
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Affiliation(s)
- C T Lewis
- Institute for Nonlinear Science, University of California-San Diego, La Jolla, CA 92093-0402, USA.
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21
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Moeller T, Buhl M, Schorr U, Distler A, Sharma AM. Salt intake and hypertension in renal transplant patients. Clin Nephrol 2000; 53:159-63. [PMID: 10749292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
BACKGROUND Dietary salt restriction is currently widely recommended as an important non-pharmacological measure for the treatment of hypertension. However, the relationship between dietary salt intake and post-transplant hypertension has not been extensively investigated. PATIENTS AND METHODS We examined the relationship between dietary salt intake and the prevalence of hypertension in 129 renal transplant patients with stable allograft function (serum creatinine < 400 micromol/l, variation in serum creatinine during the preceding two months < 20%). Salt intake was assessed by measuring 24-hour urinary excretion of sodium on an unrestricted diet. Hypertension was defined based on the prescription of antihypertensive medication, and the number of antihypertensive drugs was considered a surrogate marker for severity of hypertension. Patients were divided into tertiles based on urinary sodium excretion and analyzed by chi2-testing. RESULTS The prevalence of hypertension was 74% and the mean sodium excretion was 178 mmol/d (range: 56 to 603). There was no statistical difference in the frequency of antihypertensive medication between patients with low (76%, UNa = 107 mmol/d), medium (73%, UNa = 178 mmol/d), or high sodium (73%, UNa = 272 mmol/d) excretion. Furthermore, the number of antihypertensive drugs (in treated patients) was similar between the tertiles. There was also no correlation between urinary sodium excretion and systolic (r = -0.05) or diastolic (r = 0.08) blood pressure levels. CONCLUSION We conclude that dietary salt intake in transplant patients with stable allograft function is higher than currently recommended. There is, however, no relationship between salt intake and the prevalence of hypertension in these patients. These data do not support the hypothesis that the prevalence or severity of post-transplant hypertension is markedly affected by dietary salt intake.
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Affiliation(s)
- T Moeller
- Department of Internal Medicine, Universitätsklinikum Benjamin Franklin, Berlin, Germany
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22
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Abstract
UNLABELLED Efficacy and complications of intravitreally injected tissue plasminogen activator (rt-PA) and sulfahexafluoride gas (SF6) in submacular hemorrhage are demonstrated. PATIENTS AND METHODS Fifty-three patients with submacular hemorrhage were treated (27 women, 26 men, mean age 79 +/- 1 years). Causes of hemorrhage were a choroidal neovascularization in 47 patients and macroaneurysm in 6 patients. After i.v. administration of 500 mg acetazolamide and disinfection of the conjunctiva, 50 micrograms rt-PA in 0.1 ml (BSS) and 0.5 ml SF6 were injected intravitreally. The patient was positioned prone for 24 h. RESULTS In 23 patients with choroidal neovascularization visual acuity improved by 2 lines and more; in 12 patients vision remained unchanged. In 12 patients visual acuity deteriorated. In 5 of 6 patients with a macroaneurysm vision improved from less than 0.1 to 0.1-0.5. Postoperative complications were four cases of vitreous hemorrhage and one case of endophthalmitis. CONCLUSION The intravitreal injection of rt-PA and SF6 is an alternative method for treatment of submacular hemorrhage.
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Affiliation(s)
- M Buhl
- Universitäts-Augenklinik München
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23
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Abstract
In order to gain a better understanding of the healing processes after plate fixation and indirect reduction, Baumgaertel designed a reproducible fracture model for the sheep femur in 1992 so that the differences between anatomical (rigid) and biological (bridging) fixation could be investigated. It was demonstrated that indirect reduction and bridge plating was superior to direct fragment reduction and anatomical fixation in respect to radiology, biomechanics and microangiography. In this study, it was shown that bony bridging of the fracture gap and mineralization of callus occurred faster and more efficiently after indirect than after direct and anatomical reduction. Bone healing was identified as beginning in the 2.-3. week after indirect and only in the sixth week after direct reduction. The increased breaking strength of the indirectly reduced femora at 8 weeks can be attributed to this process. In addition, the consequences of applying the PC-Fix for biological plating were investigated. The values for bone healing were improved by applying a plate with only point contact to the bone, thus conserving the periosteal blood supply.
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Affiliation(s)
- F Baumgaertel
- Unfallchirurgisch-Orthopädische Klinik, Städtische Kliniken Fulda
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24
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Buhl M, Liesenhoff O, Kampik A. [Pathogenesis and therapy of central serous retinopathy]. Ophthalmologe 1994; 91:741-4. [PMID: 7849425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
UNLABELLED There is no consensus in the literature on the etiology and therapy of central serous retinopathy. We conducted a retrospective study to find out whether patients treated with argon laser coagulation (ALK) experienced long-term visual acuity improvement. We were also concerned to find whether choroidal perfusion was involved in the etiology. PATIENTS In all, 28 patients (4 women/24 men) with RCS confirmed by angiography were analyzed. All patients were followed up from 1988 to 1992. Patients with chronic recurrent RCS were not considered. Angiography was performed to examine the type and localization of the leakage and also the choroidal perfusion. Patients who were treated with ALK were compared with patients who were not. RESULTS Only 9 patients were treated with carefully directed ALK. Their mean visual acuity was 0.5 (STD 0.09) before therapy. After treatment the mean visual acuity was improved to an average of 0.8 (0.23). The follow-up time was up to 56 weeks. The patients without ALK had an initial visual acuity of 0.6 (0.21) which improved to 0.8 (0.22) during an observation period of 60 weeks. By the end of the study the visual acuity was the same in both groups. In 46% of all patients delayed choroidal perfusion was seen on angiography. CONCLUSION There was no difference in visual acuity between patients treated with and without ALK. The angiographic examinations suggest general changes in choroidal perfusion in patients with RCS.
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Affiliation(s)
- M Buhl
- Augenklinik, Universität München
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25
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Affiliation(s)
- S B Mohan
- Department of Anaesthesia & Intensive Care, Sultan Qaboos University Hospital, Sultanate of Oman
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26
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Abstract
Adrenocortical adenomas (ACA) are frequently discovered at autopsy. Nowadays, modern radiologic techniques incidentally uncover the usually silent ACA during lifetime. On the basis of various reports and the results of endocrine tests, i.e. dexamethasone suppression (DST) and CRH response, we characterize 3 major types of functioning ACA. Type I ACA (cortisol < 100 nmol/l after 1 mg dexamethasone (DXM)) comprises the majority of the so-called 'nonfunctioning' adrenocortical adenomas. However, these adenomas may not be 'truly nonfunctioning' ACA, as their mean FMAX/ACTHMAX-ratio after CRH is significantly higher than in controls without ACA. Also, 19-iodocholesterol adrenal scan has shown persistent adrenal uptake despite DXM administration in some patients with normal DST. Type II ACA ('pre-Cushing's') is comparable to the euthyroid autonomous adenoma. The results of function tests suggest the existence of an ACTH-hyperresponsive subtype. Finally, type III ACA are associated with overt hypercortisolism. An ACTH-responsive and an ACTH-unresponsive form can be characterized. A continuous functional spectrum and the transition between the different types of adenomas is discussed.
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Affiliation(s)
- J Hensen
- Department of Medicine, Freie Universität Berlin, Germany
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27
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Abstract
The hypothesis that blood rheology is of prognostic value in patients with arteriosclerotic diseases was tested in a prospective study of 843 patients at a rehabilitation clinic. They were tested for blood serum and plasma viscosity, hematocrit, fibrinogen, red cell aggregation and deformability, erythrocyte sedimentation rate, white cell count, cholesterol, and triglycerides. End points were defined as a second stroke or myocardial infarction or cardiovascular death within two years of the initial examination. Patients suffering such end points as compared with matched pairs (n = 74; matching criteria: identical manifestation of arteriosclerosis, identical sex and similar age and risk factors) had significantly higher native blood viscosity (p = 0.002), red cell aggregation (p = 0.01), serum viscosity (p = 0.01), fibrinogen (p = 0.02), and cholesterol (p = 0.01). It is concluded that rheologic factors are associated with the prognosis in patients with arteriosclerotic diseases.
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Affiliation(s)
- K L Resch
- Department of Physical Medicine, University of Munich, FRG
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28
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Abstract
The hypothesis that blood rheology is of prognostic value in stroke patients was tested in a prospective study. A total of 523 patients in the rehabilitation phase of stroke (outside the acute phase reaction after stroke) were tested for blood, serum and plasma viscosity, haematocrit, fibrinogen, red cell aggregation and deformability, ESR, white cell count, cholesterol and triglycerides. Endpoints were defined as a second stroke (lethal or not) within 2 years after the initial examination. Patients suffering such endpoints exhibit elevated blood viscosity, red cell aggregation, plasma and serum viscosity, fibrinogen and cholesterol levels, compared to patients without endpoints. It is concluded that rheological factors are associated with the prognosis after a first stroke.
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Affiliation(s)
- E Ernst
- Department of Physical Medicine and Rehabilitation, University of Vienna, Austria
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29
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Hensen J, Buhl M, Bähr V, Oelkers W. Endocrine activity of the "silent" adrenocortical adenoma is uncovered by response to corticotropin-releasing hormone. Klin Wochenschr 1990; 68:608-14. [PMID: 2165544 DOI: 10.1007/bf01660959] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The purpose of this study was to ascertain whether the pituitary-adrenal responses to human corticotropin-releasing hormone (hCRH) in "non-functioning" adrenocortical adenoma would uncover a functional activity in these adrenal nodules. Eleven patients with incidentally discovered "silent" adrenocortical adenoma and eleven controls were studied. The initial clinical and laboratory examination, including an overnight 1 mg dexamethasone suppression test, revealed no abnormalities in any of the subjects. IR-ACTH and serum steroids (F, S, P, 17OHP, 18OHB, and aldosterone) were normal in both controls and patients. After pulse IV injection of 100 micrograms hCRH, the cortisol response was significantly exaggerated (P = 0.01). Stimulated plasma ACTH levels were, however, significantly lower in patients than in controls (P = 0.01), indicating counter-feedback regulation of cortisol. The peak cortisol/peak ACTH ratio (Fmax/ACTHmax) in the patients was significantly elevated (26.8 +/- 4.37 nmol/ng vs. 14.6 +/- 2.16 nmol/ng, P = 0.02). Two further patients with incidentally discovered "pre-Cushing's" adrenocortical adenoma displayed an even higher ratio (43.5 and 45.5 nmol/ng). In established Cushing's syndrome due to an autonomous adrenocortical adenoma, suppression of ACTH and of the ACTH response to hCRH occurs with a very high basal cortisol/basal ACTH ratio. Our findings suggest some functional activity even in clinically "silent" adrenocortical adenoma. Response to hCRH uncovers a continuous spectrum between adrenocortical adenoma, "pre-Cushing's", and Cushing's syndrome.
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Affiliation(s)
- J Hensen
- Endokrinologische Abteilung, Universitätsklinikum Steglitz, Freie Universität Berlin
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30
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Abstract
We analysed cumulative disease frequencies in the first 231 adult Danish AIDS patients with life tables. There was a certain hierarchical pattern in the occurrence of complicating diseases. Herpes zoster, Kaposi's sarcoma and Pneumocystis carinii pneumonia were early manifestations, whereas diseases caused by cytomegalovirus and atypical mycobacteria tended to occur later in the course of AIDS. Compared with all other AIDS patients, homosexual men were more likely to develop Kaposi's sarcoma, cytomegalovirus chorioretinitis and mucocutaneous herpes simplex virus infection. The proportion of patients who developed particular diseases changed with calendar time. Most striking was a three to fourfold decrease in diseases caused by cytomegalovirus. In conclusion, the study showed that disease frequencies in patients with AIDS may vary with the patients risk behaviour and duration of AIDS, and that the frequencies of particular diseases may change with calendar time.
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Affiliation(s)
- C Pedersen
- Department of Infectious Diseases, Hvidovre Hospital, University of Copenhagen, Denmark
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31
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Teglbjaerg LL, Mathiesen LR, Søeberg B, Nielsen L, Thorsen B, Buhl M, Pedersen C, Bonnevie O, Nielsen C, Vestergaard BF. Zidovudine treatment of AIDS and ARC in Denmark 1987. Scand J Infect Dis 1989; 21:367-73. [PMID: 2685984 DOI: 10.3109/00365548909167439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In 1987, a total of 138 Danish patients (94 AIDS and 44 ARC) received treatment with zidovudine, a total observation period of 572 treatment months. 15 AIDS and 1 ARC patient died after a median of 70 days (range 2-295). In the ARC group 4 patients developed AIDS (3 Pneumocystis carinii pneumonia, 1 Kaposi's sarcoma). Among the AIDS patients 38 new opportunistic infections were reported. 24 of these opportunistic infections occurred within 6 weeks after treatment initiation. 79 patients were observed for more than 3 months, 25 of these had their daily dose zidovudine reduced, usually from 1,200 mg to 600 mg, 9 others were temporarily off drug. HIV antigen was analyzed in serum samples from 93 patients. Of these, 28 (52%) of 54 initially HIV antigen-positive became antigen-negative, 7 (18%) of 39 initially HIV antigen-negative became antigen-positive within the first 8 weeks of zidovudine treatment. In 57 patients the total count of CD4+ cells were evaluated. A significant increase in the number of CD4+ cells was observed during treatment. In nearly all patients an increase in MCV and a decrease in neutrophil count was observed. 44 of the patients received a total of 307 blood transfusions on 94 occasions and 19 (14%) patients required multiple transfusions. The mortality among the AIDS patients was significantly lower compared to historical controls. In our experience zidovudine treatment is reasonably well tolerated and the side effects are manageable.
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Affiliation(s)
- L L Teglbjaerg
- Department of Infectious Diseases, Hvidovre Hospital, Copenhagen, Denmark
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32
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Møller Rasmussen J, Teisner B, Jepsen HH, Svehag SE, Knudsen F, Kirstein H, Buhl M. Three cases of factor I deficiency: the effect of treatment with plasma. Clin Exp Immunol 1988; 74:131-6. [PMID: 3219799 PMCID: PMC1541714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Three patients with congenital factor I deficiency associated with different clinical manifestations are described. Case 1 had one single episode of meningococcal disease, case 2 experienced four episodes of meningococcal disease and several other severe infections, whereas case 3, without known predisposition for infections, died from a subacute immune-complex mediated syndrome, resembling polyarteritis nodosa. Family studies in cases 1 and 2 revealed healthy individuals with factor I concentrations below the lower reference limit, indicating heterozygous carriers. The pedigree analyses were consistent with autosomal codominant inheritance. The estimated minimal frequency of the deficient gene was 0.002. Pedigree analysis was not performed in case 3 but the father and sister was found to be probable heterozygous carriers. Cases 2 and 3 were treated with infusions of freshly frozen plasma (FFP) (40 and 27 ml/kg bodyweight) during acute illness and the immunochemical complement profile was monitored. Following plasma infusion factor I was cleared from the circulation with a half-life of 29-45 h. The plasma infusions induced generation of C3d and C4d, increase in native factor B and C3 concentrations and disappearance of Ba split products. Native C3 and C4 increased to normal concentrations and remained normal till 16 days after the plasma infusions, whereas native factor B decreased to preinfusion levels 8 days after plasma infusion. It is concluded, that congenital factor I deficiency can present with different clinical manifestations and may be more prevalent than hitherto anticipated. Furthermore, infusion of blood products containing small amounts of functional factor I can partly normalize the complement profile, with a more prolonged effect on C3 and C4 than on factor B metabolism.
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33
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Bro S, Buhl M, Jørgensen PJ, Kristensen T, Hørder M. Serum zinc in homosexual men with antibodies against human immunodeficiency virus. Clin Chem 1988; 34:1929-30. [PMID: 3416468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- S Bro
- Dept. of Clin. Chem., Odense University Hospital, Denmark
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34
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Affiliation(s)
- S Bro
- Dept. of Clin. Chem., Odense University Hospital, Denmark
| | - M Buhl
- Dept. of Clin. Chem., Odense University Hospital, Denmark
| | - P J Jørgensen
- Dept. of Clin. Chem., Odense University Hospital, Denmark
| | - T Kristensen
- Dept. of Clin. Chem., Odense University Hospital, Denmark
| | - M Hørder
- Dept. of Clin. Chem., Odense University Hospital, Denmark
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35
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Espersen JO, Klaerke A, Buhl M, Eriksen EF, Fode K, Krøyer L, Lindeberg H, Madsen CB, Strange P, Wohlert L. Treatment of cervical disc disease using Cloward's technique. Part V. The effect of reoperations. Acta Neurochir (Wien) 1987; 88:34-8. [PMID: 3425411 DOI: 10.1007/bf01400512] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Among 1,106 patients with cervical disc disease in whom Cloward's operation had been performed over a fifteen-year period, 145 patients were reoperated upon with a new Cloward procedure. In the 1st year after the first operation 3/4 of the patients were operated upon on the previous level, whereas reoperations performed later mainly were done on new levels. The effect of the reoperation was poorer than the effect of the 1st operation. Early reoperations--which were due to: an initially unsatisfactory clinical course, postoperative complications or graft problems--had a poor result, but late reoperations--which were caused by relapses--showed a result corresponding to the first operation. The frequency of relapses leading to a 2nd Cloward operation was 8.8% in the first year falling to 0.2% in the following years of observation.
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Affiliation(s)
- J O Espersen
- Department of Neurosurgery, University Hospital, Aarhus, Denmark
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36
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Petersen OF, Buhl M, Eriksen EF, Fode K, Klaerke A, Krøyer L, Lindeberg H, Madsen CB, Miletic T, Strange P. The significance of preoperative radiological examinations in patients treated with Cloward's operation. Acta Neurochir (Wien) 1987; 88:39-45. [PMID: 3425412 DOI: 10.1007/bf01400513] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
During a fifteen-year period 1,106 patients with symptoms and signs of cervical disc disease underwent Cloward's operation. Plain x-rays were performed in 94%, but the severity and extension of degenerative changes had no prognostic value. In 91% of the patients myelography was performed and in recent years mainly metrizamide was used as it was found to be more accurate. The findings on the myelograms were correlated according to age, severity and number of affected disc levels, but were independent of the duration of symptoms. Patients with medullary symptoms were found more often than not to have an anterior indentation into the spinal canal whereas most patients with radicular symptoms had wide cervical root sleeves or lateral compression. The best outcome was found among patients with monosegmental symptoms and signs and one affected disc level on the myelogram underlining that the indication for surgery in cervical disc disease should be based on both clinical and radiological findings.
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Affiliation(s)
- O F Petersen
- Department of Neurosurgery, University Hospital, Aarhus, Denmark
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37
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Yomtovian R, Ceynar J, Kepner JL, Buhl M. Predeposit autologous blood transfusion: an analysis of donor attitudes and attributes. QRB Qual Rev Bull 1987; 13:45-50. [PMID: 3104857 DOI: 10.1016/s0097-5990(16)30104-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Predeposit autologous blood transfusion now accounts for 11% of the total transfusion volume at Saint Cloud Hospital in Minnesota. This hospitalwide program represents a major positive quality assurance/risk management change in transfusion practice. To understand the factors responsible for the success of the program, a questionnaire was sent to 224 patients donating during a 26-month period ending July 1, 1985. Factors important in the increasing utilization of the program include donor acceptance, clinician referrals, and perceived lack of conflict with the homologous donation process.
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38
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Buhl M, Wetzel WE, Ehret B. [Epidemiological findings on the incidence of caries in the deciduous teeth of young children]. Dtsch Zahnarztl Z 1986; 41:1038-42. [PMID: 3469073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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39
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Kay L, Buhl M, Dichmann O. [Solitary malignant schwannoma]. Ugeskr Laeger 1984; 146:2786. [PMID: 6515902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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40
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Eriksen EF, Buhl M, Fode K, Klaerke A, Krøyer L, Lindeberg H, Madsen CB, Strange P, Wohlert L, Espersen JO. Treatment of cervical disc disease using Cloward's technique. The prognostic value of clinical preoperative data in 1,106 patients. Acta Neurochir (Wien) 1984; 70:181-97. [PMID: 6711363 DOI: 10.1007/bf01406648] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
During a fifteen-year period 1,106 patients underwent Cloward's operation due to cervical disc disease. An analysis of the clinical features showed that the diseases had a very complex pattern of symptoms and signs. In young patients a syndrome of herniated disc predominated whereas a clinical picture of "cervical spondylosis" was found more often in the elderly. It was demonstrated that best results were obtained in young patients, patients with slight symptoms and patients with monoradicular symptoms. A short duration of symptoms is essential for a good outcome, and, on the basis of the data presented, operation is recommended 3 months after the onset of symptoms of cervical disc disease, if previous conservative treatment has failed.
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41
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Voldby B, Petersen OF, Buhl M, Jakobsen P, Ostergaard R. Reversal of cerebral arterial spasm by intrathecal administration of a calcium antagonist (nimodipine). Acta Neurochir (Wien) 1984; 70:243-54. [PMID: 6546832 DOI: 10.1007/bf01406653] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Specific antagonists to the influx of calcium, necessary for the excitation-contraction coupling process in arterial smooth muscle, are potentially useful in the treatment of cerebral vasospasm but systemic hypotension might limit their clinical applicability. We studied the effect of the calcium antagonist nimodipine (BAY e 9736) on cerebral arterial spasm, intraventricular pressure and blood pressure (BP), when administered into the cerebral ventricles of the dog. Cerebral vasospasm was produced by the injection of autologous blood into the cisterna magna. In a group of 8 dogs, 100 micrograms of nimodipine was injected into the lateral ventricle. The effect of the drug on the basilar artery was monitored angiographically. Nimodipine always relieved spasm, and often the relaxation surpassed the resting vessel diameter. In a control group, the injection of placebo did not relax the spastic arteries. Determinations using gas chromatography of nimodipine in CSF and blood demonstrated that a concentration of 1 microgram/ml in cisternal CSF was sufficient to reduce spasm while concomitant plasma concentrations of 0.004 micrograms/ml did not result in significant BP reduction.
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42
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Strange P, Buhl M, Eriksen EF, Fode K, Klaerke A, Krøyer L, Lindeberg H, Madsen CB, Wohlert L, Espersen JO. [Cervical disk disease treated by the Cloward method. A study of 1106 patients]. Ugeskr Laeger 1984; 146:1919-24. [PMID: 6506285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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43
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Espersen JO, Buhl M, Eriksen EF, Fode K, Klaerke A, Krøyer L, Lindeberg H, Madsen CB, Strange P, Wohlert L. Treatment of cervical disc disease using Cloward's technique. I. General results, effect of different operative methods and complications in 1,106 patients. Acta Neurochir (Wien) 1984; 70:97-114. [PMID: 6377837 DOI: 10.1007/bf01406047] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
During the period from April, 1965, to October, 1979, 1,106 patients with symptoms or signs of cervical disc disease were operated on using Cloward's technique. 94% of the patients alive filled in a questionnaire forwarded on October, 1980. The study revealed that 81% experienced an immediate effect of the operation, and 63% were in a better condition than preoperatively at the time of the questionnaire. It appeared that the effect of the operation 1 year postoperatively was independent of age and observation time, but the functional result and postoperative working capacity were very significantly better in young patients, but still independent of observation time. The result was independent of the number of primarily inserted grafts, cutting of the posterior spinal ligament or the finding of a free herniated disc. Use of calf bone grafts resulted in more reoperations. Primary complications were registered in 13% of the patients, reduced to 5% after 3 months. 3 patients developed a severe tetraplegia, and 6 patients died within 3 months of the operation.
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44
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Wohlert L, Buhl M, Eriksen EF, Fode K, Klaerke A, Krøyer L, Lindeberg H, Madsen CB, Strange P, Espersen JO. Treatment of cervical disc disease using Cloward's technique. III. Evaluation of cervical spondylotic myelopathy in 138 cases. Acta Neurochir (Wien) 1984; 71:121-31. [PMID: 6731054 DOI: 10.1007/bf01401157] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Among 1,106 patients with cervical disc disease treated with Cloward's operation over a fifteen-year period, 138 patients had symptoms and signs of spinal cord involvement. The median symptom duration was one year. Nearly all had gait disturbances, 63% had spasticity of the lower extremities and 11% had various degrees of tetraplegia. Three months after surgery 78% of the patients were found to have some symptoms, but only 5% had no symptoms at all. At the time of the questionnaire (average 7.7 years postoperatively) 46% of the patients stated they were still affected by the operation. The duration of preoperative symptoms was of significance to the outcome, but age, sex, and severity of myelopathy were not. It was demonstrated that patients with medullary involvement had a higher annual mortality rate than patients with radicular symptoms, and that this rate depended on the severity of the spinal cord symptoms.
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Abstract
Previous reports concerning the treatment of symptoms deriving from prolapsed lumbar disc with systemic administration of the potent steroid dexamethasone, have shown favourable results. The present clinical study includes 39 patients with symptoms of prolapsed lumbar disc, treated in a controlled double-blind investigation with dexamethasone or placebo. Twenty patients had provable effect of the treatment, 19 had no effect. Nineteen patients received dexamethasone (13 + effect), 20 received placebo (7 + effect). The groups were fully comparable, and the difference is not statistically significant. During a period of 3 months 50% of the patients who improved by the treatment of either group had recurrences leading to operation. It is concluded that the effect of dexamethasone given intramuscularly does not seem to exceed that of placebo in the treatment of prolapsed lumbar disc.
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46
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Buhl M. [Steroid therapy for persistent pain after lumbar prolapse surgery]. Ugeskr Laeger 1979; 141:2746-7. [PMID: 531964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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47
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Buhl M, Charles P, Jensen FT. Elimination of scalp blood flow by headband during dynamic brain scintigraphy. J Nucl Med 1975; 16:679-81. [PMID: 1151492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The effect of the application of a headband during brain scintigraphy was investigated in 11 healthy volunteers. In each person, extracranial recording of a bolus of 99mTc-pertechnetate injected intravenously was done on two occasions during a scintillation camera. On one occasion a narrow sphygmomanometer cuff encircling the head from brow to occiput and inflated to 300 mmHg was applied during measurements; another time, the procedure was identical except for the headband. A comparison between counting rates under the derived time-activity curves showed significantly lower values on headband application (p less than 0.01). Static scintigrams consisting of the first 300,000 counts recorded after bolus release with and without headband application show a clear delineation of the headband position with prevention of "halo" appearance about the cranial cavity. It has thus been possible by simple means to reduce the irrelevant radionuclide distribution which, especially during dynamic investigations of cerebral circulation, constitutes a source of error.
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48
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Olivarius BD, Buhl M, Hansen HH. Letter: Forecasting subarachnoid haemorrhage. Br Med J 1975; 1:91. [PMID: 1109669 PMCID: PMC1672219 DOI: 10.1136/bmj.1.5949.91-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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50
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Buhl M. [Herpes simplex encephalitis. Acute necrotizing encephalitis and benign herpes simplex encephalitis]. Ugeskr Laeger 1974; 136:815-21. [PMID: 4363988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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