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81.
Patricia Hirt-Minkowski Hans-Peter Marti Gideon Hönger Denis Grandgirard Stephen L. Leib Patrizia Amico Stefan Schaub 《Transplant immunology》2014,30(1):1-6
Progressive interstitial fibrosis and tubular atrophy (IF/TA) is a leading cause of chronic allograft dysfunction. Increased extracellular matrix remodeling regulated by matrix metalloproteases (MMPs) and their inhibitors (TIMPs) has been implicated in the development of IF/TA. The aim of this study was to investigate whether urinary/serum MMPs/TIMPs correlate with subclinical IF/TA detected in surveillance biopsies within the first 6 months post-transplant. We measured eight different MMPs/TIMPs simultaneously in urine and serum samples from patients classified as normal histology (n = 15), IF/TA 1 (n = 15) and IF/TA 2–3 (n = 10). There was no difference in urinary MMPs/TIMPs among the three groups, and only 1/8 serum MMPs/TIMPs (i.e. MMP-1) was significantly elevated in biopsies with IF/TA 2–3 (p = 0.01). In addition, urinary/serum MMPs/TIMPs were not different between surveillance biopsies demonstrating an early development of IF/TA (i.e. delta IF/TA ≥ 1 compared to a previous biopsy obtained three months before; n = 11) and stable grade of IF/TA (i.e. delta IF/TA = 0; n = 20). Next, we investigated whether urinary/serum MMP/TIMP levels are elevated during acute subclinical tubulitis in surveillance biopsies obtained within the first 6 months post-transplant (n = 25). Compared to biopsies with normal histology, serum MMPs/TIMPs were not different; however, all urinary MMP/TIMP levels were numerically higher during subclinical tubulitis (MMP-1, MMP-7, TIMP-1 with p ≤ 0.04). We conclude that urinary/serum MMPs/TIMPs do hardly correlate with existing or early developing IF/TA in surveillance biopsies obtained within the first 6 months post-transplant. This could be explained by the dynamic process of extracellular matrix remodeling, which seems to be active during acute tubulo-interstitial injury/inflammation, but not in quiescent IF/TA. 相似文献
82.
Male rabbits were injured by a single mechanical dilatation of the aorta and then injected with prednisone 2 mg/kg saline for 14 days or starved. Morphological studies and biochemical measurements of the collagen metabolism, the content of alpha-amino nitrogen, RNA, DNA, water and fat, and the aorta to serum ratio of 125I-albumin were performed on the intima-media layer of the descending thoracic aorta. Prednisone inhibited the intimal thickening. In the media the infiltration by mononuclear cells, the proliferation and regeneration of the smooth muscle cells and the calcification were reduced. Prednisone caused a decrease in 0.45 M NaCl soluble collagen as well as in the dialysable and non-dialysable 14C-hydroxyproline fractions. The total amount of collagen, elastin and alpha-amino nitrogen was unchanged, whereas the 14C-proline incorporation in the non-dialysable protein fraction was inhibited to a greater extent than the 14C-hydroxyproline synthesis. The findings indicate that prednisone inhibits the biosynthesis of collagen, which is inhibited to a greater extent than the general protein synthesis. Prednisone increased the dialysable to non-dialysable 14C-hydroxyproline ratio consistent with a relative increase in the catabolism of newly synthesized collagen. The aortic content of RNA and DNA was reduced consistent with the inhibition of protein synthesis and cell proliferation. Finally prednisone decreased the aortic content of water when related to the wet weight and increased the aortic content of fat. The aorta to serum ratio of 125I-albumin was not influenced by prednisone. It is concluded that administration of glucocorticoid for 14 days exerts an inhibitory action on the histological reaction to injury as well as on the biosynthesis of collagen of the repair processes in vascular connective tissue. A comparison with the effects of prednisone on undamaged rabbit aorta (Manthorpe et al. 1974) demonstrates that the metabolism of collagen of vascular connective tissue during repair is more sensitive to the antianabolic effects of prednisone than collagen in the non-injured aorta. Starvation caused an increase of the aortic percentage of water but otherwise had no influence on the repair processes in the vascular connective tissue. 相似文献
83.
Hans-Peter Welzel Gerhard Kossmehl Gunnar Engelmann Barbara Neumann Ulla Wollenberger Frieder Scheller Werner Schrder 《Macromolecular chemistry and physics.》1996,197(10):3355-3363
Electrocopolymerization of 3-thiopheneacetic acid ( 1 ) and 3-methylthiophene ( 2 ) under various conditions produces poly{(3-methylthiophene-2,5-diyl)-co-[3-(carboxymethyl)thiophene-2,5-diyl]} ( 3 ). By activation of the carboxy groups with dicyclohexylcarbodiimide (DCC) lactate oxidase (LOD) is covalently bonded to the surface of the electrode. In this way a lactate sensor was formed which is applicable for the determination of lactate in micromolar concentrations. 相似文献
84.
Yusuf A. Rajabally MD FRCP H. Stephan Goedee MD PhD Shahram Attarian MD PhD Hans-Peter Hartung MD PhD FRCP 《Muscle & nerve》2020,62(1):34-40
Since March 2020, the COVID-19 pandemic has led to the need to re-think the delivery of services to patients with chronic dysimmune neuropathies. Telephone/video consultations have become widespread but have compounded concerns about objective evaluation. Therapeutic decisions need, more than ever before, to be considered in the best interests of both patients, and society, while not denying function-preserving/restoring treatment. Immunoglobulin therapy and plasma exchange, for those treated outside of the home, expose patients to the hazards of hospital or outpatient infusion centers. Steroid therapy initiation and continuation pose increased infectious risk. Immunosuppressant therapy similarly becomes highly problematic, with the risks of treatment continuation enhanced by uncertainties regarding duration of the pandemic. The required processes necessitate considerable time and effort especially as resources and staff are re-deployed to face the pandemic, but are essential for protecting this group of patients and as an integral part of wider public health actions. 相似文献
85.
Zumel-Marne Angela Kundi Michael Castaño-Vinyals Gemma Alguacil Juan Petridou Eleni Th Georgakis Marios K. Morales-Suárez-Varela Maria Sadetzki Siegal Piro Sara Nagrani Rajini Filippini Graziella Hutter Hans-Peter Dikshit Rajesh Woehrer Adelheid Maule Milena Weinmann Tobias Krewski Daniel ′t Mannetje Andrea Momoli Franco Lacour Brigitte Mattioli Stefano Spinelli John J. Ritvo Paul Remen Thomas Kojimahara Noriko Eng Amanda Thurston Angela Lim Hyungryul Ha Mina Yamaguchi Naohito Mohipp Charmaine Bouka Evdoxia Eastman Chelsea Vermeulen Roel Kromhout Hans Cardis Elisabeth 《Journal of neuro-oncology》2020,147(2):427-440
Journal of Neuro-Oncology - We used data from MOBI-Kids, a 14-country international collaborative case–control study of brain tumors (BTs), to study clinical characteristics of the tumors in... 相似文献
86.
87.
Julia Torabi Juan P. Rocca Krystina Choinski Katherine Lorenzen Camille Yongue Michelle L. Lubetzsky Melvon E. Herbert Attasit Chokechanachaisakul Maria Ajaimy Layla Kamal Enver Akalin Milan Kinkhabwala Jay A. Graham 《Clinical transplantation》2018,32(1)
Background
We analyze our outcomes utilizing imported allografts as a strategy to shorten wait list time for pancreas transplantation.Methods
This is an observational retrospective cohort of 26 recipients who received either a locally procured (n = 16) or an imported pancreas graft (n = 10) at our center between January 2014 and May 2017. Wait list times of this cohort were compared to UNOS Region 9 (New York State and Western Vermont). Hospital financial data were also reviewed to analyze the cost‐effectiveness of this strategy.Results
Imported pancreas grafts had significantly increased cold ischemia times (CIT) and peak lipase (PL) levels compared to locally procured grafts (CIT 827 vs 497 minutes; P = .001, PL 563 vs 157 u/L; P = .023, respectively). There were no differences in graft or patient survival. The median wait time was significantly lower for simultaneous kidney‐pancreas transplants at our center (518 days, n = 21) compared to Region 9 (1001 days, n = 65) P = .038. Despite financial concerns, the cost of transport for imported grafts was offset by lower standard acquisition costs.Conclusions
Imported pancreas grafts may be a cost‐effective strategy to increase organ utilization and shorten wait times in regions with longer waiting times. 相似文献88.
Alex D. Sheftel Oliver Stehling Antonio J. Pierik Hans-Peter Els?sser Ulrich Mühlenhoff Holger Webert Anna Hobler Frank Hannemann Rita Bernhardt Roland Lill 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(26):11775-11780
Mammalian adrenodoxin (ferredoxin 1; Fdx1) is essential for the synthesis of various steroid hormones in adrenal glands. As a member of the [2Fe-2S] cluster-containing ferredoxin family, Fdx1 reduces mitochondrial cytochrome P450 enzymes, which then catalyze; e.g., the conversion of cholesterol to pregnenolone, aldosterone, and cortisol. The high protein sequence similarity between Fdx1 and its yeast adrenodoxin homologue (Yah1) suggested that Fdx1, like Yah1, may be involved in the biosynthesis of heme A and Fe/S clusters, two versatile and essential protein cofactors. Our study, employing RNAi technology to deplete human Fdx1, did not confirm this expectation. Instead, we identified a Fdx1-related mitochondrial protein, designated ferredoxin 2 (Fdx2) and found it to be essential for heme A and Fe/S protein biosynthesis. Unlike Fdx1, Fdx2 was unable to efficiently reduce mitochondrial cytochromes P450 and convert steroids, indicating that the two ferredoxin isoforms are highly specific for their substrates in distinct biochemical pathways. Moreover, Fdx2 deficiency had a severe impact, via impaired Fe/S protein biogenesis, on cellular iron homeostasis, leading to increased cellular iron uptake and iron accumulation in mitochondria. We conclude that mammals depend on two distinct mitochondrial ferredoxins for the specific production of either steroid hormones or heme A and Fe/S proteins. 相似文献
89.
Alexander René Schrott Monik Jimenez Jae-Woong Hwang Joseph Fiorellini Hans-Peter Weber 《Clinical oral implants research》2009,20(10):1170-1177
Background: The question of the importance of keratinized mucosa around dental implants for the prevention of peri-implant disease could not be answered in the relevant literature so far.
Objective: To investigate the influence of peri-implant keratinized mucosa on long-term peri-implant soft-tissue health and stability over a period of 5 years.
Material and methods: A total of 386 mandibular dental implants were placed in 73 completely edentulous patients, and subsequently restored with fixed full-arch prostheses. At prosthesis delivery (baseline) and after 3, 6, 12, 18, 24, 36, 48 and 60 months, modified plaque index (mPlI), modified sulcus bleeding index (mBI), distance between implant shoulder and mucosal margin (DIM) and width of peri-implant keratinized mucosa (KM) were recorded. Statistical analysis included multivariate logistic regression, multivariate ordinal logistic regression, generalized estimating equations and Bonferroni's correction.
Results: Fifty-eight patients with 307 implants completed the 5-year study. Statistically significantly higher plaque accumulation on lingual sites (mean mPlI 0.67, SD 0.85), bleeding tendencies on lingual sites (mean mBI 0.22, SD 0.53) and larger soft-tissue recession on buccal sites (mean DIM −0.69 mm, SD 1.11 mm) were found when the width of KM was <2 mm, compared to sites with≥2 mm of KM (mean mPlI 0.40, SD 0.68, P =0.001; mean mBI 0.13, SD 0.41, P <0.01; mean DIM −0.08 mm, SD 0.86 mm, P <0.001). The width of keratinized mucosa had no effect on bleeding tendency or plaque accumulation on buccal sites ( P >0.05).
Conclusion: In patients exercising good oral hygiene and receiving regular implant maintenance therapy, implants with a reduced width of <2 mm of peri-implant keratinized mucosa were more prone to lingual plaque accumulation and bleeding as well as buccal soft-tissue recession over a period of 5 years. 相似文献
Objective: To investigate the influence of peri-implant keratinized mucosa on long-term peri-implant soft-tissue health and stability over a period of 5 years.
Material and methods: A total of 386 mandibular dental implants were placed in 73 completely edentulous patients, and subsequently restored with fixed full-arch prostheses. At prosthesis delivery (baseline) and after 3, 6, 12, 18, 24, 36, 48 and 60 months, modified plaque index (mPlI), modified sulcus bleeding index (mBI), distance between implant shoulder and mucosal margin (DIM) and width of peri-implant keratinized mucosa (KM) were recorded. Statistical analysis included multivariate logistic regression, multivariate ordinal logistic regression, generalized estimating equations and Bonferroni's correction.
Results: Fifty-eight patients with 307 implants completed the 5-year study. Statistically significantly higher plaque accumulation on lingual sites (mean mPlI 0.67, SD 0.85), bleeding tendencies on lingual sites (mean mBI 0.22, SD 0.53) and larger soft-tissue recession on buccal sites (mean DIM −0.69 mm, SD 1.11 mm) were found when the width of KM was <2 mm, compared to sites with≥2 mm of KM (mean mPlI 0.40, SD 0.68, P =0.001; mean mBI 0.13, SD 0.41, P <0.01; mean DIM −0.08 mm, SD 0.86 mm, P <0.001). The width of keratinized mucosa had no effect on bleeding tendency or plaque accumulation on buccal sites ( P >0.05).
Conclusion: In patients exercising good oral hygiene and receiving regular implant maintenance therapy, implants with a reduced width of <2 mm of peri-implant keratinized mucosa were more prone to lingual plaque accumulation and bleeding as well as buccal soft-tissue recession over a period of 5 years. 相似文献
90.
Pattern of serum autoantibodies allows accurate distinction between a tumor and pathologies of the same organ 总被引:1,自引:0,他引:1
Nicole Ludwig Andreas Keller Nicole Comtesse Stefanie Rheinheimer Christian Pallasch Ulrike Fischer Klaus Fassbender Wolf Ingo Steudel Hans-Peter Lenhof Eckart Meese 《Clinical cancer research》2008,14(15):4767-4774
PURPOSE: Recent studies impressively showed the diagnostic potential of seroreactivity patterns for different tumor types, offering the prospect for low-cost screening of numerous tumor types simultaneously. One of the major challenges toward this goal is to prove that seroreactivity profiles do not only allow for identifying a tumor but also allow for distinguishing tumors from other pathologies of the same organ. EXPERIMENTAL DESIGN: We chose glioma as a model system and tested 325 sera (88 glioma, 95 intracranial tumors, 60 other brain pathologies, and 82 healthy controls) for seroreactivity on a panel of 35 antigens. RESULTS: We were able to discriminate between glioma and all other sera with cross-validated specificity of 86.1%, sensitivity of 85.2%, and accuracy of 85.8%. We obtained comparably good results for the separation of glioma versus nontumor brain pathologies and glioma versus other intracranial tumors. CONCLUSION: Our study provides first evidence that seroreactivity patterns allow for an accurate discrimination between a tumor and pathologies of the same organ even between different tumor types of the same organ. 相似文献