25 results on '"Pfaff, L."'
Search Results
2. Nonclassical estrogen receptor [alpha] signaling mediates negative feedback in the female mouse reproductive axis
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Glidewell-Kenney, C., Hurley, L.A., Pfaff, L., Weiss, J., Levine, J.E., and Jameson, J.L.
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Gonadotropin releasing hormone -- Research ,Neuroendocrinology -- Research ,Reproduction -- Research ,Estrogen -- Receptors ,Estrogen -- Research ,Science and technology - Abstract
Ovarian estrogen exerts both positive and negative feedback control over luteinizing hormone (LH) secretion during the ovulatory cycle. Estrogen receptor (ER) [alpha] but not ER[beta] knockout mice lack estrogen feedback. Thus, estrogen feedback appears to be primarily mediated by ER[alpha]. However, it is now recognized that, in addition to binding to estrogen response elements (EREs) in DNA to alter target gene transcription, ER[alpha] signals through ERE-independent or nonclassical pathways, and the relative contributions of these pathways in conveying estrogen feedback remain unknown. Previously we created a knockin mouse model expressing a mutant form of ER[alpha] (AA) with ablated ERE-dependent but intact ERE-independent activity. Breeding this allele onto the ER[alpha]-null (-/-) background, we examine the ability of ERE-independent ER[alpha] signaling pathways to convey estrogen feedback regulation of the female hypothalamic-pituitary axis in vivo. ER[[alpha].sup.-/AA] exhibited 69.9% lower serum LH levels compared with ER[[alpha].sup.-/-] mice. Additionally, like wild type, ER[[alpha].sup.-/AA] mice exhibited elevated LH after ovariectomy (OVX). Furthermore, the post-OVX rise in serum LH was significantly suppressed by estrogen treatment in OVX ERa-/AA mice. However, unlike wild type, both ER[[alpha].sup.-/AA] and ER[[alpha].sup.-/-] mice failed to exhibit estrous cyclicity, spontaneous ovulation, or an afternoon LH surge response to estrogen. These results indicate that ERE-independent ER[alpha] signaling is sufficient to convey a major portion of estrogen's negative feedback actions, whereas positive feedback and spontaneous ovulatory cyclicity require ERE-dependent ER[alpha] signaling. neuroendocrine | reproduction
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- 2007
3. Neoadjuvante Chemotherapie (NACT) beim frühen Mammakarzinom: retrospektive Analyse von 346 Fällen bezüglich pathologischer Komplettremission (pCR)
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Ritter, B, additional, Pfaff, L, additional, Sauer, G, additional, Ott, G, additional, Aulitzky, WE, additional, and Gerteis, A, additional
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- 2018
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4. Maturity effects on chemical composition, silage fermentation and digestibility of whole plant grain sorghum and soya-bean silages fed to beef cattle
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Esmail, S.H.M., primary, Bolsen, K.K., additional, and Pfaff, L., additional
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- 1991
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5. "OUR OWN COUNTRY CANADA," BEING AN ACCOUNT OF THE NATIONAL ASPIRATIONS OF THE PRINCIPAL LANDSCAPE ARTISTS IN MONTREAL AND TORONTO 1860–1980 Dennis Reid
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Pfaff, L. R.
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- 1984
6. System des ungarischen Privatrechtes Carl Putz
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Pfaff, L.
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- 1871
7. der Legalisirungszwang bei Tabularurtunden Horaz Krasnopolski
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Pfaff, L.
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- 1880
8. Force Tests on a Separable-Nose Crew Escape Capsule in Proximity to the Parent Fuselage with Cold Flow Rocket Plume Simulation at Mach Numbers 2 through 5.
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ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFS TN, Jones, Jerry H., Pfaff, L. J., ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFS TN, Jones, Jerry H., and Pfaff, L. J.
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Static force tests were conducted on a separable-nose crew escape capsule in the presence of the forward section of the airplane fuselage. The capsule escape rocket jet plume was simulated with air heated to a total temperature of approximately 100F. Data were obtained at Mach numbers from 2 through 5 at capsule angles of attack from -15 to 25 deg and angles of sideslip from 0 to 15 deg for various positions of the capsule relative to the fuselage section. All testing was conducted at a fuselage angle of attack and angle of sideslip of zero. Reynolds number, based on a model length of 18.1 in., ranged from 5,700,000 to 12,300,000. Results are presented showing the effects of the fuselage section on the aerodynamic characteristics of the capsule, with and without simulation of the escape rocket exhaust plume. (Author), Prepared in cooperation with ARO, Inc., Tullahoma, Tenn.
- Published
- 1969
9. Lawren Harris and the International Exhibition of Modern Art
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Pfaff, L. R., primary
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- 1984
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10. Portraits by Lawren Harris: Salem Bland and Others
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Pfaff, L. R., primary
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- 1978
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11. Expansion, persistence, and efficacy of donor memory-like NK cells infused for posttransplant relapse.
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Shapiro, Roman M., Birch, Grace C., Guangan Hu, Cadavid, Juliana Vergara, Nikiforow, Sarah, Baginska, Joanna, Ali, Alaa K., Tarannum, Mubin, Sheffer, Michal, Abdulhamid, Yasmin Z., Rambaldi, Benedetta, Arihara, Yohei, Reynolds, Carol, Halpern, Max S., Rodig, Scott J., Cullen, Nicole, Wolff, Jacquelyn O., Pfaff, L., Lane, Andrew A., and Lindsley, R. Coleman
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HOMOGRAFTS , *INTERLEUKIN-2 , *KILLER cells , *DISEASE relapse , *RESEARCH funding , *HEMATOPOIETIC stem cell transplantation - Abstract
BackgroundResponses to conventional donor lymphocyte infusion for postallogeneic hematopoietic cell transplantation (HCT) relapse are typically poor. Natural killer (NK) cell-based therapy is a promising modality to treat post-HCT relapse.MethodsWe initiated this ongoing phase I trial of adoptively transferred cytokine-induced memory-like (CIML) NK cells in patients with myeloid malignancies who relapsed after haploidentical HCT. All patients received a donor-derived NK cell dose of 5 to 10 million cells/kg after lymphodepleting chemotherapy, followed by systemic IL-2 for 7 doses. High-resolution profiling with mass cytometry and single-cell RNA sequencing characterized the expanding and persistent NK cell subpopulations in a longitudinal manner after infusion.ResultsIn the first 6 enrolled patients on the trial, infusion of CIML NK cells led to a rapid 10- to 50-fold in vivo expansion that was sustained over months. The infusion was well tolerated, with fever and pancytopenia as the most common adverse events. Expansion of NK cells was distinct from IL-2 effects on endogenous post-HCT NK cells, and not dependent on CMV viremia. Immunophenotypic and transcriptional profiling revealed a dynamic evolution of the activated CIML NK cell phenotype, superimposed on the natural variation in donor NK cell repertoires.ConclusionGiven their rapid expansion and long-term persistence in an immune-compatible environment, CIML NK cells serve as a promising platform for the treatment of posttransplant relapse of myeloid disease. Further characterization of their unique in vivo biology and interaction with both T cells and tumor targets will lead to improvements in cell-based immunotherapies.Trial RegistrationClinicalTrials.gov NCT04024761.FundingDunkin' Donuts, NIH/National Cancer Institute, and the Leukemia and Lymphoma Society. [ABSTRACT FROM AUTHOR]
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- 2022
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12. Reviews
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Pfaff, L. R.
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- 1984
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13. Enhancing diffusion-weighted prostate MRI through self-supervised denoising and evaluation.
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Pfaff L, Darwish O, Wagner F, Thies M, Vysotskaya N, Hossbach J, Weiland E, Benkert T, Eichner C, Nickel D, Wuerfl T, and Maier A
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- Humans, Male, Prostate diagnostic imaging, Prostate pathology, Image Processing, Computer-Assisted methods, Algorithms, Diffusion Magnetic Resonance Imaging methods, Prostatic Neoplasms diagnostic imaging, Signal-To-Noise Ratio
- Abstract
Diffusion-weighted imaging (DWI) is a magnetic resonance imaging (MRI) technique that provides information about the Brownian motion of water molecules within biological tissues. DWI plays a crucial role in stroke imaging and oncology, but its diagnostic value can be compromised by the inherently low signal-to-noise ratio (SNR). Conventional supervised deep learning-based denoising techniques encounter challenges in this domain as they necessitate noise-free target images for training. This work presents a novel approach for denoising and evaluating DWI scans in a self-supervised manner, eliminating the need for ground-truth data. By leveraging an adapted version of Stein's unbiased risk estimator (SURE) and exploiting a phase-corrected combination of repeated acquisitions, we outperform both state-of-the-art self-supervised denoising methods and conventional non-learning-based approaches. Additionally, we demonstrate the applicability of our proposed approach in accelerating DWI scans by acquiring fewer image repetitions. To evaluate denoising performance, we introduce a self-supervised methodology that relies on analyzing the characteristics of the residual signal removed by the denoising approaches., (© 2024. The Author(s).)
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- 2024
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14. Evolutionary and functional characterization of lagomorph guanylate-binding proteins: a story of gain and loss and shedding light on expression, localization and innate immunity-related functions.
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Schelle L, Côrte-Real JV, Fayyaz S, Del Pozo Ben A, Shnipova M, Petersen M, Lotke R, Menon B, Matzek D, Pfaff L, Pinheiro A, Marques JP, Melo-Ferreira J, Popper B, Esteves PJ, Sauter D, Abrantes J, and Baldauf HM
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- Animals, Rabbits, Humans, Mice, Carrier Proteins, GTP-Binding Proteins genetics, GTP-Binding Proteins metabolism, Immunity, Innate genetics, Interferons metabolism, Lagomorpha metabolism
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Guanylate binding proteins (GBPs) are an evolutionarily ancient family of proteins that are widely distributed among eukaryotes. They belong to the dynamin superfamily of GTPases, and their expression can be partially induced by interferons (IFNs). GBPs are involved in the cell-autonomous innate immune response against bacterial, parasitic and viral infections. Evolutionary studies have shown that GBPs exhibit a pattern of gene gain and loss events, indicative for the birth-and-death model of evolution. Most species harbor large GBP gene clusters that encode multiple paralogs. Previous functional and in-depth evolutionary studies have mainly focused on murine and human GBPs. Since rabbits are another important model system for studying human diseases, we focus here on lagomorphs to broaden our understanding of the multifunctional GBP protein family by conducting evolutionary analyses and performing a molecular and functional characterization of rabbit GBPs. We observed that lagomorphs lack GBP3, 6 and 7 . Furthermore, Leporidae experienced a loss of GBP2 , a unique duplication of GBP5 and a massive expansion of GBP4 . Gene expression analysis by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) and transcriptome data revealed that leporid GBP expression varied across tissues. Overexpressed rabbit GBPs localized either uniformly and/or discretely to the cytoplasm and/or to the nucleus. Oryctolagus cuniculus (oc)GBP5L1 and rarely ocGBP5L2 were an exception, colocalizing with the trans-Golgi network (TGN). In addition, four ocGBPs were IFN-inducible and only ocGBP5L2 inhibited furin activity. In conclusion, from an evolutionary perspective, lagomorph GBPs experienced multiple gain and loss events, and the molecular and functional characteristics of ocGBP suggest a role in innate immunity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Schelle, Côrte-Real, Fayyaz, del Pozo Ben, Shnipova, Petersen, Lotke, Menon, Matzek, Pfaff, Pinheiro, Marques, Melo-Ferreira, Popper, Esteves, Sauter, Abrantes and Baldauf.)
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- 2024
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15. Self-supervised MRI denoising: leveraging Stein's unbiased risk estimator and spatially resolved noise maps.
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Pfaff L, Hossbach J, Preuhs E, Wagner F, Arroyo Camejo S, Kannengiesser S, Nickel D, Wuerfl T, and Maier A
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Thermal noise caused by the imaged object is an intrinsic limitation in magnetic resonance imaging (MRI), resulting in an impaired clinical value of the acquisitions. Recently, deep learning (DL)-based denoising methods achieved promising results by extracting complex feature representations from large data sets. Most approaches are trained in a supervised manner by directly mapping noisy to noise-free ground-truth data and, therefore, require extensive paired data sets, which can be expensive or infeasible to obtain for medical imaging applications. In this work, a DL-based denoising approach is investigated which operates on complex-valued reconstructed magnetic resonance (MR) images without noise-free target data. An extension of Stein's unbiased risk estimator (SURE) and spatially resolved noise maps quantifying the noise level with pixel accuracy were employed during the training process. Competitive denoising performance was achieved compared to supervised training with mean squared error (MSE) despite optimizing the model without noise-free target images. The proposed DL-based method can be applied for MR image enhancement without requiring noise-free target data for training. Integrating the noise maps as an additional input channel further enables the regulation of the desired level of denoising to adjust to the preference of the radiologist., (© 2023. The Author(s).)
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- 2023
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16. Rapid depolymerization of poly(ethylene terephthalate) thin films by a dual-enzyme system and its impact on material properties.
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Tarazona NA, Wei R, Brott S, Pfaff L, Bornscheuer UT, Lendlein A, and Machatschek R
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Enzymatic hydrolysis holds great promise for plastic waste recycling and upcycling. The interfacial catalysis mode, and the variability of polymer specimen properties under different degradation conditions, add to the complexity and difficulty of understanding polymer cleavage and engineering better biocatalysts. We present a systemic approach to studying the enzyme-catalyzed surface erosion of poly(ethylene terephthalate) (PET) while monitoring/controlling operating conditions in real time with simultaneous detection of mass loss and changes in viscoelastic behavior. PET nanofilms placed on water showed a porous morphology and a thickness-dependent glass transition temperature ( T
g ) between 40°C and 44°C, which is >20°C lower than the Tg of bulk amorphous PET. Hydrolysis by a dual-enzyme system containing thermostabilized variants of Ideonella sakaiensis PETase and MHETase resulted in a maximum depolymerization of 70% in 1 h at 50°C. We demonstrate that increased accessible surface area, amorphization, and Tg reduction speed up PET degradation while simultaneously lowering the threshold for degradation-induced crystallization., Competing Interests: The authors declare no competing interests., (© 2022 The Author(s).)- Published
- 2022
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17. Trainable joint bilateral filters for enhanced prediction stability in low-dose CT.
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Wagner F, Thies M, Denzinger F, Gu M, Patwari M, Ploner S, Maul N, Pfaff L, Huang Y, and Maier A
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- Humans, Reproducibility of Results, Neural Networks, Computer, Algorithms, Signal-To-Noise Ratio, Image Processing, Computer-Assisted methods, Tomography, X-Ray Computed methods
- Abstract
Low-dose computed tomography (CT) denoising algorithms aim to enable reduced patient dose in routine CT acquisitions while maintaining high image quality. Recently, deep learning (DL)-based methods were introduced, outperforming conventional denoising algorithms on this task due to their high model capacity. However, for the transition of DL-based denoising to clinical practice, these data-driven approaches must generalize robustly beyond the seen training data. We, therefore, propose a hybrid denoising approach consisting of a set of trainable joint bilateral filters (JBFs) combined with a convolutional DL-based denoising network to predict the guidance image. Our proposed denoising pipeline combines the high model capacity enabled by DL-based feature extraction with the reliability of the conventional JBF. The pipeline's ability to generalize is demonstrated by training on abdomen CT scans without metal implants and testing on abdomen scans with metal implants as well as on head CT data. When embedding RED-CNN/QAE, two well-established DL-based denoisers in our pipeline, the denoising performance is improved by 10%/82% (RMSE) and 3%/81% (PSNR) in regions containing metal and by 6%/78% (RMSE) and 2%/4% (PSNR) on head CT data, compared to the respective vanilla model. Concluding, the proposed trainable JBFs limit the error bound of deep neural networks to facilitate the applicability of DL-based denoisers in low-dose CT pipelines., (© 2022. The Author(s).)
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- 2022
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18. Molecular and Biochemical Differences of the Tandem and Cold-Adapted PET Hydrolases Ple628 and Ple629, Isolated From a Marine Microbial Consortium.
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Meyer Cifuentes IE, Wu P, Zhao Y, Liu W, Neumann-Schaal M, Pfaff L, Barys J, Li Z, Gao J, Han X, Bornscheuer UT, Wei R, and Öztürk B
- Abstract
Polybutylene adipate terephthalate (PBAT) is a biodegradable alternative to polyethylene and can be broadly used in various applications. These polymers can be degraded by hydrolases of terrestrial and aquatic origin. In a previous study, we identified tandem PETase-like hydrolases (Ples) from the marine microbial consortium I1 that were highly expressed when a PBAT blend was supplied as the only carbon source. In this study, the tandem Ples, Ple628 and Ple629, were recombinantly expressed and characterized. Both enzymes are mesophilic and active on a wide range of oligomers. The activities of the Ples differed greatly when model substrates, PBAT-modified polymers or PET nanoparticles were supplied. Ple629 was always more active than Ple628. Crystal structures of Ple628 and Ple629 revealed a structural similarity to other PETases and can be classified as member of the PETases IIa subclass, α/β hydrolase superfamily. Our results show that the predicted functions of Ple628 and Ple629 agree with the bioinformatic predictions, and these enzymes play a significant role in the plastic degradation by the consortium., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Meyer Cifuentes, Wu, Zhao, Liu, Neumann-Schaal, Pfaff, Barys, Li, Gao, Han, Bornscheuer, Wei and Öztürk.)
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- 2022
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19. Biosensor and chemo-enzymatic one-pot cascade applications to detect and transform PET-derived terephthalic acid in living cells.
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Bayer T, Pfaff L, Branson Y, Becker A, Wu S, Bornscheuer UT, and Wei R
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Plastic waste imposes a serious problem to the environment and society. Hence, strategies for a circular plastic economy are demanded. One strategy is the engineering of polyester hydrolases toward higher activity for the biotechnological recycling of polyethylene terephthalate (PET). To provide tools for the rapid characterization of PET hydrolases and the detection of degradation products like terephthalic acid (TPA), we coupled a carboxylic acid reductase (CAR) and the luciferase LuxAB. CAR converted TPA into the corresponding aldehydes in Escherichia coli , which yielded bioluminescence that not only semiquantitatively reflected amounts of TPA in hydrolysis samples but is suitable as a high-throughput screening assay to assess PET hydrolase activity. Furthermore, the CAR-catalyzed synthesis of terephthalaldehyde was combined with a reductive amination cascade in a one-pot setup yielding the corresponding diamine, suggesting a new strategy for the transformation of TPA as a product obtained from PET biodegradation., Competing Interests: The authors declare no competing interests., (© 2022 The Authors.)
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- 2022
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20. Engineering and evaluation of thermostable Is PETase variants for PET degradation.
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Brott S, Pfaff L, Schuricht J, Schwarz JN, Böttcher D, Badenhorst CPS, Wei R, and Bornscheuer UT
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Polyethylene terephthalate (PET) is a mass-produced petroleum-based synthetic polymer. Enzymatic PET degradation using, for example, Ideonella sakaiensis PETase ( Is PETase) can be a more environmentally friendly and energy-saving alternative to the chemical recycling of PET. However, Is PETase is a mesophilic enzyme with an optimal reaction temperature lower than the glass transition temperature ( T
g ) of PET, where the amorphous polymers can be readily accessed for enzymatic breakdown. In this study, we used error-prone PCR to generate a mutant library based on a thermostable triple mutant (TM) of Is PETase. The library was screened against the commercially available polyester-polyurethane Impranil DLN W 50 for more thermostable Is PETase variants, yielding four variants with higher melting points. The most promising Is PETaseTMK95N/F201I variant had a 5.0°C higher melting point than Is PETaseTM. Although this variant showed a slightly lower activity on PET at lower incubation temperatures, its increased thermostability makes it a more active PET hydrolase at higher reaction temperatures up to 60°C. Several other variants were compared and combined with selected previously published Is PETase mutants in terms of thermostability and hydrolytic activity against PET nanoparticles and amorphous PET films. Our findings indicate that thermostability is one of the most important characteristics of an effective PET hydrolase., Competing Interests: The authors declare no conflict of interest. No experiments involving animals or humans were performed in the context of this study., (© 2021 The Authors. Engineering in Life Sciences published by Wiley‐VCH GmbH.)- Published
- 2021
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21. Emotional experience is increased and emotion recognition decreased in multiple sclerosis.
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Pfaff L, Gounot D, Chanson JB, de Seze J, and Blanc F
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- Adult, Affective Symptoms etiology, Affective Symptoms psychology, Case-Control Studies, Cognition, Facial Recognition, Female, Humans, Middle Aged, Multiple Sclerosis, Relapsing-Remitting complications, Neuropsychological Tests, Recognition, Psychology, Emotions, Multiple Sclerosis, Relapsing-Remitting psychology
- Abstract
Emotional disorders in multiple sclerosis (MS) are frequently described as difficulties in recognizing facial expressions, rarely in the experience dimension. Moreover, interaction between emotional disorders and cognitive or psychological disorders remains little documented. The aim of this study is to explore emotions in MS in emotion recognition and emotional experience and compare these data with cognitive, psychological, and disease aspects. Twenty-five women with MS (MS group) and 27 healthy controls (control group) matched for age, sex, and education were assessed for emotion recognition (Florida Affect Battery) and emotional experience (International Affective Picture System Photographs). Participants were also assessed for cognitive and psychological aspects. Compared to the control group, the MS group had more difficulty in recognizing emotions, and their subjective evaluations when presented IAPS pictures were more scattered, globally increased. Emotional dimensions were each correlated with executive functions but neither correlated with alexithymia, depression, anxiety, or MS characteristics. In conclusion, MS patients present difficulties in identifying emotion and their emotional experience appears to be increased. These disorders are correlated with cognition but remain independent of psychological or disease aspects. Considering the implications that emotional disorders may have, it seems essential to take these aspects into account in clinical practice., (© 2021. The Author(s).)
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- 2021
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22. Animal Models of Neointimal Hyperplasia and Restenosis: Species-Specific Differences and Implications for Translational Research.
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Ebert MLA, Schmidt VF, Pfaff L, von Thaden A, Kimm MA, and Wildgruber M
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The process of restenosis is based on the interplay of various mechanical and biological processes triggered by angioplasty-induced vascular trauma. Early arterial recoil, negative vascular remodeling, and neointimal formation therefore limit the long-term patency of interventional recanalization procedures. The most serious of these processes is neointimal hyperplasia, which can be traced back to 4 main mechanisms: endothelial damage and activation; monocyte accumulation in the subintimal space; fibroblast migration; and the transformation of vascular smooth muscle cells. A wide variety of animal models exists to investigate the underlying pathophysiology. Although mouse models, with their ease of genetic manipulation, enable cell- and molecular-focused fundamental research, and rats provide the opportunity to use stent and balloon models with high throughput, both rodents lack a lipid metabolism comparable to humans. Rabbits instead build a bridge to close the gap between basic and clinical research due to their human-like lipid metabolism, as well as their size being accessible for clinical angioplasty procedures. Every different combination of animal, dietary, and injury model has various advantages and disadvantages, and the decision for a proper model requires awareness of species-specific biological properties reaching from vessel morphology to distinct cellular and molecular features., Competing Interests: Dr Wildgruber was supported by a grant from the Deutsche Forschungsgemeinschaft DFG (WI 3686/7-1)., (© 2021 The Authors.)
- Published
- 2021
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23. Platelet-RBC interaction mediated by FasL/FasR induces procoagulant activity important for thrombosis.
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Klatt C, Krüger I, Zey S, Krott KJ, Spelleken M, Gowert NS, Oberhuber A, Pfaff L, Lückstädt W, Jurk K, Schaller M, Al-Hasani H, Schrader J, Massberg S, Stark K, Schelzig H, Kelm M, and Elvers M
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- Aged, Aged, 80 and over, Anemia blood, Animals, Blood Platelets ultrastructure, Cell Communication physiology, Disease Models, Animal, Erythrocytes ultrastructure, Fas Ligand Protein deficiency, Fas Ligand Protein genetics, Female, Hemorheology physiology, Hemostasis physiology, Humans, In Vitro Techniques, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Microscopy, Electron, Transmission, Middle Aged, Phosphatidylserines blood, Platelet Activation physiology, Thrombosis etiology, Thrombosis pathology, Blood Platelets physiology, Erythrocytes physiology, Fas Ligand Protein blood, Thrombosis blood, fas Receptor blood
- Abstract
Red blood cells (RBCs) influence rheology, and release ADP, ATP, and nitric oxide, suggesting a role for RBCs in hemostasis and thrombosis. Here, we provide evidence for a significant contribution of RBCs to thrombus formation. Anemic mice showed enhanced occlusion times upon injury of the carotid artery. A small population of RBCs was located to platelet thrombi and enhanced platelet activation by a direct cell contact via the FasL/FasR (CD95) pathway known to induce apoptosis. Activation of platelets in the presence of RBCs led to platelet FasL exposure that activated FasR on RBCs responsible for externalization of phosphatidylserine (PS) on the RBC membrane. Inhibition or genetic deletion of either FasL or FasR resulted in reduced PS exposure of RBCs and platelets, decreased thrombin generation, and reduced thrombus formation in vitro and protection against arterial thrombosis in vivo. Direct cell contacts between platelets and RBCs via FasL/FasR were shown after ligation of the inferior vena cava (IVC) and in surgical specimens of patients after thrombectomy. In a flow restriction model of the IVC, reduced thrombus formation was observed in FasL-/- mice. Taken together, our data reveal a significant contribution of RBCs to thrombosis by the FasL/FasR pathway.
- Published
- 2018
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24. Online advertising as a public health and recruitment tool: comparison of different media campaigns to increase demand for smoking cessation interventions.
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Graham AL, Milner P, Saul JE, and Pfaff L
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- Adolescent, Cost-Benefit Analysis, Electronic Mail statistics & numerical data, Feasibility Studies, Female, Humans, Male, New Jersey, Patient Selection, Therapy, Computer-Assisted economics, Young Adult, Advertising, Internet, Marketing methods, Online Systems, Public Health, Smoking Cessation methods, Therapy, Computer-Assisted methods
- Abstract
Background: To improve the overall impact (reach x efficacy) of cessation treatments and to reduce the population prevalence of smoking, innovative strategies are needed that increase consumer demand for and use of cessation treatments. Given that 12 million people search for smoking cessation information each year, online advertising may represent a cost-efficient approach to reach and recruit online smokers to treatment. Online ads can be implemented in many forms, and surveys consistently show that consumers are receptive. Few studies have examined the potential of online advertising to recruit smokers to cessation treatments., Objective: The aims of the study were to (1) demonstrate the feasibility of online advertising as a strategy to increase consumer demand for cessation treatments, (2) illustrate the tools that can be used to track and evaluate the impact of online advertising on treatment utilization, and (3) highlight some of the methodological challenges and future directions for researchers., Methods: An observational design was used to examine the impact of online advertising compared to traditional recruitment approaches (billboards, television and radio ads, outdoor advertising, direct mail, and physician detailing) on several dependent variables: (1) number of individuals who enrolled in Web- or telephone-based cessation treatment, (2) the demographic, smoking, and treatment utilization characteristics of smokers recruited to treatment, and (3) the cost to enroll smokers. Several creative approaches to online ads (banner ads, paid search) were tested on national and local websites and search engines. The comparison group was comprised of individuals who registered for Web-based cessation treatment in response to traditional advertising during the same time period., Results: A total of 130,214 individuals responded to advertising during the study period: 23,923 (18.4%) responded to traditional recruitment approaches and 106,291 (81.6%) to online ads. Of those who clicked on an online ad, 9655 (9.1%) registered for cessation treatment: 6.8% (n = 7268) for Web only, 1.1% (n = 1119) for phone only, and 1.2% (n = 1268) for Web and phone. Compared to traditional recruitment approaches, online ads recruited a higher percentage of males, young adults, racial/ethnic minorities, those with a high school education or less, and dependent smokers. Cost-effectiveness analyses compare favorably to traditional recruitment strategies, with costs as low as US $5-$8 per enrolled smoker., Conclusions: Developing and evaluating new ways to increase consumer demand for evidence-based cessation services is critical to cost-efficiently reduce population smoking prevalence. Results suggest that online advertising is a promising approach to recruit smokers to Web- and telephone-based cessation interventions. The enrollment rate of 9.1% exceeds most studies of traditional recruitment approaches. The powerful targeting capabilities of online advertising present new opportunities to reach subgroups of smokers who may not respond to other forms of advertising. Online advertising also provides unique evaluation opportunities and challenges to determine rigorously its impact and value., Competing Interests: Conflicts of Interest: None declared.
- Published
- 2008
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25. Quantitative autoradiographic study of labeled RNA in rabbit optic nerve after intraocular injection of (3H)uridine.
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Gambetti P, Autilio-Gambetti L, Shafer B, and Pfaff LD
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- Animals, Autoradiography, Axons metabolism, Eye, Injections, Microscopy, Electron, Myelin Sheath metabolism, Neuroglia metabolism, RNA biosynthesis, Rabbits, Tritium, Optic Nerve metabolism, RNA metabolism, Uridine administration & dosage
- Abstract
The distribution of labeled RNA in the optic nerve of the rabbit was studied by quantitative ultrastructural autoradiography after the intraocular injection of [(3)H]uridine. The highest density of silver grains related to [(3)H]RNA (27-40 grains/100 microm(2)) was found in glial cell perikarya; a slightly lower density was present in the glial nuclei (19-20 grains/100 microm(2)). Axons (4-5 grains/100 microm(2)) and myelin (2-3 grains/100 microm(2)) had the lowest grain densities. 74-83% of all counted grains were located outside the axons. By comparing the grain density distribution over the axon with that expected in the case of an exclusive labeling of the surrounding myelin and glial cell processes, it was concluded that the axons contained a number of grains representing [(3)H]RNA significantly higher than that expected to scatter from myelin and glial processes. Most of these grains were concentrated at the periphery of the axon and were not related to axonal mitochondria.
- Published
- 1973
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