210 results on '"Wiesner J"'
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2. Intensive Longitudinal Social Sensing in Patients With Psychosis Spectrum Disorders: An Exploratory Pilot Study.
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von Heyden M, Grube P, Sack M, Wiesner J, Frank O, Becker K, Heintz S, Reinhard I, Hohmann S, Hirjak D, Meyer-Lindenberg A, and Braun U
- Abstract
Background: Psychosis spectrum disorders are characterized by significant alterations in social functioning, which is a major factor for patient recovery. Despite its importance, objectively quantifying the complex day-to-day social behavior in real-life settings has rarely been attempted. Here, we conducted a pilot study with wearable sensors that passively and continuously register interactions with other participants. We hypothesized that the amount and pattern of social interaction was associated with the severity of psychotic symptoms., Study Design: We recruited 7 patients with psychosis spectrum disorders and 18 team members from a Soteria-style ward. Each participant wore a radio frequency identification badge, sending and receiving signals from nearby badges, allowing passive quantification of social interactions. In addition, symptom severity was assessed weekly by the Positive and Negative Syndrome Scale (PANSS)., Study Results: During an 11-week period, we identified 17 970 interactions among patients and staff. On average, patients spent 2.6 h per day interacting, capturing relevant aspects of daily social life. Relative daily interaction time, average interaction duration, and clustering coefficient, a measure of local network integration, were significantly associated with lower PANSS scores. Self-reported interaction time did not correlate with measured interaction time or with PANSS, indicating the importance of objective markers., Conclusions: This pilot study demonstrates the feasibility of passively recording social interaction of patients and staff at high resolution and for a long observation period in a real-life setting in a psychiatric department. We show links between quantified social interaction and psychopathology that may facilitate development and personalization of targeted treatments., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.)
- Published
- 2024
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3. Revision of the genus Apterodela Rivalier, 1950 (Coleoptera, Cicindelidae).
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Matalin AV, Wiesner J, Xiong X, and Araki T
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- Animals, Animal Distribution, China, Coleoptera
- Abstract
A revision of the genus Apterodela Rivalier, 1950 is presented. The new subgenus Protoapterodela subgen. nov. with Apterodela shirakii (W. Horn, 1927) as its type species is established. The lectotype and the paralectotype of Cicindela ovipennis Bates, 1883 and Cicindela shirakii W. Horn, 1927 as well as the neotype of Cicindela lobipennis Bates, 1888 are designated. Apterodela (s. str.) bivirgulata (Fairmaire, 1889), stat. rest. is extracted from the synonym of Apterodela (s. str.) lobipennis (Bates, 1888) and is considered as a separate species. Two new species and one new subspecies from China are described as well: Apterodela (s. str.) alopecomma sp. nov.from Sichuan Province, Apterodela (s. str.) latissima sp. nov.from Yunnan Province, and Apterodela (s. str.) bivirgulata occidentalis ssp. nov.from Qinghai, Gansu, Shaanxi, Henan, Shanxi, Sichuan Provinces, and Inner Mongolia Autonomus Region. A key to identifying the species of the genus Apterodela is provided, and its taxonomic status is examined.
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- 2024
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4. Tiger beetles of the genus Tricondyla Latreille, 1822 (Coleoptera: Cicindelidae) of the Philippines, with some considerations of the taxonomy of the genus.
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Anichtchenko A and Wiesner J
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- Animals, Philippines, Animal Distribution, Coleoptera
- Abstract
The fully everted endophallus in the genus Tricondyla is studied and described for the first time. Also, the following new synonymies are established: Pseudotricondyla Naviaux, 2002 syn. nov. = Stenotricondyla Naviaux, 2002; T. (T.) aptera punctipennis Chevrolat, 1841 syn. nov. = T. (T.) aptera aptera (Olivier,1790); T. (T.) aptera lumawigi Wiesner, 1989 syn. nov. = T. (T.) ovicollis Motschulsky, 1864; T. (S.) cavifrons Schaum, 1862 syn. nov. = T. (S.) cyanipes Eschscholtz, 1829; T. (S.) gracilis Naviaux, 2002 syn. nov. = T. (S.) elongata Horn, 1906; T. (T.) huloti Naviaux, 2009 syn. nov. = T. (S.) cyanipes fuscilabris Mandl, 1964 = T. (S.) conicicollis Chaudoir, 1844. Tricondyla (S.) oblita Naviaux, 2002, syn. nov. = Tricondyla brunnipes Motschulsky, 1861. New subgeneric placement is proposed: T. (S.) elongata Horn, 1906; T. (S.) planiceps Schaum, 1862; T. (S.) gracilis Naviaux, 2002. One new species T. (T.) johnsoni sp. nov. is described from Mindanao. The taxonomic status of T. (S.) genieri Naviaux, 2008 is discussed. The species T. (S.) beccarii Gestro, 1874 is transferred from nominative subgenus to Stenotricondyla and together with T. (Stenotricondyla) doriai Gestro, 1874 excluded from the list of species of the Philippines. A key to the species is provided. Color photographs of the habitus, and diagnostic characters, including the variability of all species, are presented.
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- 2024
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5. A gender biased hidden curriculum of clinical vignettes in undergraduate medical training.
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Arsever S, Broers B, Cerutti B, Wiesner J, and Dao MD
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- Humans, Male, Female, Curriculum, Stereotyping, Education, Medical, Education, Medical, Undergraduate, Students, Medical
- Abstract
Objectives: Medical education relies extensively on clinical vignettes, yet little attention has been given to what hidden curriculum they might convey. Our research aimed to identify whether the clinical vignettes used in pre-graduate medical education transmit gender stereotypes or gender biases., Methods: We conducted a mixed quantitative and qualitative analysis of gender-related characteristics currently existing in clinical vignettes used for pre-graduate teaching and evaluation at the Geneva Faculty of Medicine., Results: 2359 vignettes were identified, of which 955 met inclusion criteria. Patients' professions and family caregiver roles showed a strongly gendered distribution, as did the healthcare professions where male physicians and female nurses were the norm. Qualitative results identified widespread stereotyped gender roles and gender expression., Conclusion: Our study reveals that the clinical vignettes used in education and evaluation materials in pre-graduate medical education in Geneva convey a gender-biased hidden curriculum, which could negatively impact patient care and undermine equal opportunity for men and women., Practice Implications: Active revision of the content and the form of clinical vignettes used in undergraduate medical education is needed using a gender lens. Based on rare gender neutral or gender transformative examples from our study, we propose guidelines for writing non-gender-biased vignettes., Competing Interests: Declaration of Competing Interest This study has been funded by the Department of Community Medicine and Primary Care (Fonds Mimosa) of the Faculty of Medicine at the University of Geneva, Switzerland. The funding source had no influence on the content or the results of this research. The authors declare no conflict of interest., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2023
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6. Philippine species of the genus Prothyma Hope, 1838 (Coleoptera: Cicindelidae). Part 2. Subgenus Symplecthyma Rivalier, 1964.
- Author
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Anichtchenko A and Wiesner J
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- Animals, Philippines, Animal Distribution, Coleoptera
- Abstract
The Philippine species of the subgenus Symplecthyma Rivalier, 1964 within the genus Prothyma Hope, 1838 are revised to include eight species. Prothyma (Symplecthyma) bella Dheurle & Colas, 2018 syn. nov. is synonymized with Prothyma (Symplecthyma) coerulea opacosericea Horn, 1929 comb. nov.; Prothyma (Symplecthyma) boholensis Dheurle, 2012 syn. nov. and P. (Symplecthyma) nitida Rivalier, 1964 syn. nov. are synonymized with Prothyma (Symplecthyma) aeneoparva Horn, 1934. Four new species from Mindanao are described: Prothyma (Symplecthyma) inopinata sp. nov., Prothyma (Symplecthyma) eureka sp. nov., Prothyma (Symplecthyma) sciakyi sp. nov. and Prothyma (Symplecthyma) kapuka sp. nov. Taxonomic problems in the subgenus Symplecthyma are discussed. Keys to species are provided. Color photographs of the habitus and diagnostic characters, including their variability among all species, are presented.
- Published
- 2023
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7. MicroCT data provide evidence correcting the previous misidentification of an Eocene amber beetle (Coleoptera, Cicindelidae) as an extant species.
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Schmidt J, Scholz S, Wiesner J, and Will K
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- Animals, Amber, X-Ray Microtomography, Extinction, Psychological, Fossils, Coleoptera
- Abstract
The fossil record suggests some insect species have a marked longevity. The oldest fossils purported to represent extant insect species are from the Oligocene and Eocene. One of the most cited fossils is the extant tiger beetle Tetracha carolina (Coleoptera: Cicindelidae) that was identified over a century ago by Walther Horn in Eocene Baltic amber. We examined this and compared it to the previously described cincindelid Baltic amber fossil Palaeoiresina cassolai using X-ray microscopy and 3D imaging techniques. We conclude that Horn's fossil tiger beetle specimen is conspecific with the Eocene P. cassolai and is a member of an extinct stem group lineage of Cicindelidae. Based on a review of all the tiger beetle fossils described from Cretaceous and Paleogene deposits, we found that the assignment of these fossil species to extant lineages is not supported. There are currently no synapomorphies known from fossils that can provide evidence for Cretaceous Manticorni or Megacephalini nor is there evidence for Eocene Iresina. We provide evidence that rejects the idea of a recent beetle species persisting since the Eocene period, which is crucial for using the currently known fossil Cicindelidae species to calibrate divergence dating of beetle phylogenies., (© 2023. Springer Nature Limited.)
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- 2023
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8. The Philippines species of the genus Prothyma Hope, 1838 (Coleoptera: Cicindelidae) Part 1: Subgenera Prothyma Hope, 1838, Genoprothyma Rivalier, 1964 and Parasymplecthyma subgen. nov.
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Wiesner J and Anichtchenko A
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- Animals, Philippines, Animal Distribution, Coleoptera
- Abstract
The Philippines species of Prothyma Hope, 1838 (Prothyma s.str., Genoprothyma Rivalier, 1964 and Parasymplecthyma subgen. nov.) are revised to include 12 species. Prothyma (Genoprothyma) rotundatocuprascens Horn, 1923, and Prothyma (Genoprothyma) confluenteangustata Horn, 1924, are elevated to species rank; Prothyma (Symplecthyma) claudinae Dheurle, 2012 is synonymized with Prothyma (Genoprothyma) tenuipenis Horn, 1934; and two species are described: Prothyma (Genoprothyma) masbateensis sp. nov. and Prothyma (Genoprothyma) miltonmedinai sp. nov. The subgenus Parasymplecthyma subgen. nov., its unique species Prothyma (Parasymplethyma) johnsoni sp. nov. are described. Keys to Prothyma subgenera and to the Philippines species are provided. Color photographs of the habitus and diagnostic characters, also showing their variability, are presented.
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- 2023
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9. Calochroa miroklichai sp. nov., a new species from Thailand with rectification of different concepts of Calochroa tritoma (Schmidt-Goebel) and comparisons to similar species. (Coleoptera: Cicindelidae).
- Author
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Moravec J, Dheurle C, and Wiesner J
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- Animals, Thailand, Animal Distribution, Ecosystem, Coleoptera
- Abstract
A new species of the genus Calochroa Hope, 1838 is described as new to science from Thailand. Two different concepts of Calochroa tritoma (Schmidt-Goebel, 1846) are rectified here, stating that the correct concept of C. tritoma (fully corresponding to the holotype in NMPC) is that presented by Naviaux (1991), Naviaux & Pinratana (2004) and Klícha & Ďuríček (2021), while C. tritoma sensu Pearson et al. (2020) is described here as Calochroa miroklichai sp. nov. Accordingly, C. tritoma sensu Acciavatti & Pearson (1989) represents a different, probably an undescribed species. C. anometallescens (W. Horn, 1893) and Calochroa laurae (Gestro, 1893), as well as the new species, have been partly misidentified as C. tritoma in collections. The occurrence of C. tritoma is newly restricted to Thailand and Myanmar only. The above-mentioned species, as well as Calochroa fumikoae Wiesner & Phyu, 2019 are compared to C. miroklichai sp. nov. Calochroa goebeli (W. Horn, 1895), treated in literature either as a "variety" or junior synonym of C. anometallescens (or confused with C. tritoma), proved to represent a separate species. Some other taxa and discrepancies within the genus are discussed. Habitats and characters of several species versus their relations to the genus Cosmodela Rivalier, 1961 also are annotated. Habitus and diagnostic characters are illustrated in colour photographs, and photographs of the habitus and labels of type specimens of C. tritoma, C. laurae and C. goebeli are presented here for the first time.
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- 2023
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10. Revision of the Therates fruhstorferi complex (Coleoptera, Cicindelidae).
- Author
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Matalin AV and Wiesner J
- Subjects
- Animals, Animal Distribution, Coleoptera
- Abstract
The taxonomic structure of the Therates fruhstorferi species complex (sensu lato) within the batesi-species group is revised. The lectotypes and paralectotypes of Therates fruhstorferi W. Horn, 1902 and Therates fruhstorferi sauteri W. Horn, 1912 are designated. Therates biserratus Tan, Mo, Liang, 1991 and T. vitalisi ida Mandl, 1954 are restored from the synonyms of T. vitalisi W. Horn, 1913 as the separate species and subspecies, respectively while T. sauteri is considered as a separate species, but not as a subspecies of T. fruhstorferi. Three species and two subspecies are described as new: T. fruhstorferi australis ssp. n.-from southern Vietnam; T. pseudovitalisi sp. n.-from northern Laos; T. pseudovitalisi tibetana ssp. n.-from eastern Tibet, China; T. hunanensis sp. n.-from the Chinese Province Hunan; T. ziyardamensis sp. n.-from northern Myanmar. An identification key and distribution map of the species of Therates fruhstorferi complex are provided.
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- 2023
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11. Optimized Method of 3D Scaffold Seeding, Cell Cultivation, and Monitoring Cell Status for Bone Tissue Engineering.
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Krolinski A, Sommer K, Wiesner J, Friedrich O, and Vielreicher M
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- Osteogenesis, Cell Differentiation, Bone and Bones, Cell Proliferation, Printing, Three-Dimensional, Tissue Engineering methods, Tissue Scaffolds
- Abstract
The cultivation of cells in 3D systems is commonly regarded to be more physiological than in 2D as it comes much closer to the natural situation in tissues in many different aspects. However, 3D cell culture is much more complex. Cells within the pores of a printed 3D scaffold face a special situation concerning cell-material interaction and cell adhesion, cell proliferation, and supply of medium and oxygen into the core of the scaffolds. Biological assays (for cell proliferation, viability, and activity) have been validated primarily for 2D cell cultures and need to be adapted for 3D cultures. Likewise, in imaging, a number of points need to be taken into account in order to get a clear picture of the cells in 3D scaffolds, preferably with the method of multiphoton microscopy. Here, we describe a method for pretreatment and cell seeding of porous inorganic composite scaffolds (α-TCP/HA) for bone tissue engineering and for cultivation of the cell-scaffold constructs. The analytical methods described are the cell proliferation assay and the ALP activity assay. A step-by-step protocol is provided here that safely tackles typical difficulties that arise with this 3D cell-scaffold setting. In addition, MPM imaging of cells is described both with and without labeling. The combination of biochemical assays and imaging provides valuable insights into the possibilities of analysis with this 3D cell-scaffold system., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2023
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12. Stromal remodeling regulates dendritic cell abundance and activity in the tumor microenvironment.
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Papadas A, Deb G, Cicala A, Officer A, Hope C, Pagenkopf A, Flietner E, Morrow ZT, Emmerich P, Wiesner J, Arauz G, Bansal V, Esbona K, Capitini CM, Matkowskyj KA, Deming DA, Politi K, Abrams SI, Harismendy O, and Asimakopoulos F
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- CD8-Positive T-Lymphocytes metabolism, Dendritic Cells metabolism, Humans, Immunity, Innate, Lymphocytes metabolism, Versicans metabolism, Neoplasms pathology, Tumor Microenvironment
- Abstract
Stimulatory type 1 conventional dendritic cells (cDC1s) engage in productive interactions with CD8
+ effectors along tumor-stroma boundaries. The paradoxical accumulation of "poised" cDC1s within stromal sheets is unlikely to simply reflect passive exclusion from tumor cores. Drawing parallels with embryonic morphogenesis, we hypothesized that invasive margin stromal remodeling generates developmentally conserved cell fate cues that regulate cDC1 behavior. We find that, in human T cell-inflamed tumors, CD8+ T cells penetrate tumor nests, whereas cDC1s are confined within adjacent stroma that recurrently displays site-specific proteolysis of the matrix proteoglycan versican (VCAN), an essential organ-sculpting modification in development. VCAN is necessary, and its proteolytic fragment (matrikine) versikine is sufficient for cDC1 accumulation. Versikine does not influence tumor-seeding pre-DC differentiation; rather, it orchestrates a distinctive cDC1 activation program conferring exquisite sensitivity to DNA sensing, supported by atypical innate lymphoid cells. Thus, peritumoral stroma mimicking embryonic provisional matrix remodeling regulates cDC1 abundance and activity to elicit T cell-inflamed tumor microenvironments., Competing Interests: Declaration of interests F.A. and C.H. are listed as inventors on US patent US20170258898A1: “Versikine for inducing or potentiating an immune response.”, (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)- Published
- 2022
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13. New or rare Madagascar tiger beetles26. A new species of the genus Pogonostoma Klug from northwestern Madagascar and a revised key to the Pogonostoma (P.) srnkai species-group (Coleoptera: Cicindelidae).
- Author
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Moravec JI, Wiesner J, and Jocque M
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- Animal Distribution, Animals, Madagascar, Coleoptera
- Abstract
A new species of the genus Pogonostoma Klug, 1835, P. (Pogonostoma) mahimborondrense Moravec Wiesner sp. nov. is described as new to science from the Mahimborondro protected area in Northern Highlands, northwestern Madagascar. By its unique complex of diagnostic characters, the new species is incomparable to any other species within the genus. It is placed here into the Pogonostoma (P.) srnkai species-group (in the concept presented in the monograph of the genus by Moravec 2007). A revised key to species of the species-group is presented in order to supplement the key in the monograph. Habitus and diagnostic characters of the new species are illustrated in colour photographs. Maps and photos of the occurrence of the new species in Mahimborondro are also presented.
- Published
- 2022
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14. Ponatinib sensitizes myeloma cells to MEK inhibition in the high-risk VQ model.
- Author
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Flietner E, Wen Z, Rajagopalan A, Jung O, Watkins L, Wiesner J, You X, Zhou Y, Sun Y, Kingstad-Bakke B, Callander NS, Rapraeger A, Suresh M, Asimakopoulos F, and Zhang J
- Subjects
- Animals, Apoptosis, CD8-Positive T-Lymphocytes, Cell Line, Tumor, Imidazoles, Mice, Mitogen-Activated Protein Kinase Kinases, Protein Kinase Inhibitors pharmacology, Protein Kinase Inhibitors therapeutic use, Pyridazines, Antineoplastic Agents pharmacology, Antineoplastic Agents therapeutic use, Multiple Myeloma pathology
- Abstract
Multiple myeloma (MM) is a malignant plasma cell cancer. Mutations in RAS pathway genes are prevalent in advanced and proteasome inhibitor (PI) refractory MM. As such, we recently developed a VQ MM mouse model recapitulating human advanced/high-risk MM. Using VQ MM cell lines we conducted a repurposing screen of 147 FDA-approved anti-cancer drugs with or without trametinib (Tra), a MEK inhibitor. Consistent with its high-risk molecular feature, VQ MM displayed reduced responses to PIs and de novo resistance to the BCL2 inhibitor, venetoclax. Ponatinib (Pon) is the only tyrosine kinase inhibitor that showed moderate MM killing activity as a single agent and strong synergism with Tra in vitro. Combined Tra and Pon treatment significantly prolonged the survival of VQ MM mice regardless of treatment schemes. However, this survival benefit was moderate compared to that of Tra alone. Further testing of Tra and Pon on cytotoxic CD8
+ T cells showed that Pon, but not Tra, blocked T cell function in vitro, suggesting that the negative impact of Pon on T cells may partially counteract its MM-killing synergism with Tra in vivo. Our study provides strong rational to comprehensively evaluate agents on both MM cells and anti-MM immune cells during therapy development., (© 2022. The Author(s).)- Published
- 2022
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15. Novel Insights into Pyrrolizidine Alkaloid Toxicity and Implications for Risk Assessment: Occurrence, Genotoxicity, Toxicokinetics, Risk Assessment-A Workshop Report.
- Author
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Schrenk D, Fahrer J, Allemang A, Fu P, Lin G, Mahony C, Mulder PPJ, Peijnenburg A, Pfuhler S, Rietjens IMCM, Sachse B, Steinhoff B, These A, Troutman J, and Wiesner J
- Subjects
- Animals, Food Contamination analysis, Risk Assessment, Toxicokinetics, Pyrrolizidine Alkaloids toxicity, Teas, Herbal
- Abstract
This paper reports on the major contributions and results of the 2nd International Workshop of Pyrrolizidine Alkaloids held in September 2020 in Kaiserslautern, Germany. Pyrrolizidine alkaloids are among the most relevant plant toxins contaminating food, feed, and medicinal products of plant origin. Hundreds of PA congeners with widespread occurrence are known, and thousands of plants are assumed to contain PAs. Due to certain PAs' pronounced liver toxicity and carcinogenicity, their occurrence in food, feed, and phytomedicines has raised serious human health concerns. This is particularly true for herbal teas, certain food supplements, honey, and certain phytomedicinal drugs. Due to the limited availability of animal data, broader use of in vitro data appears warranted to improve the risk assessment of a large number of relevant, 1,2-unsaturated PAs. This is true, for example, for the derivation of both toxicokinetic and toxicodynamic data. These efforts aim to understand better the modes of action, uptake, metabolism, elimination, toxicity, and genotoxicity of PAs to enable a detailed dose-response analysis and ultimately quantify differing toxic potencies between relevant PAs. Accordingly, risk-limiting measures comprising production, marketing, and regulation of food, feed, and medicinal products are discussed., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)
- Published
- 2022
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16. Regulatory Perspectives of Pyrrolizidine Alkaloid Contamination in Herbal Medicinal Products.
- Author
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Wiesner J
- Subjects
- Animals, Drug Contamination, Herbal Medicine, Phytotherapy, Plants, Medicinal, Pyrrolizidine Alkaloids toxicity
- Abstract
The toxicity of plants containing certain pyrrolizidine alkaloids has long been recognized in grazing animals and humans. Genotoxicity and carcinogenicity data from in vitro and in vivo (animal) studies were published over the last few decades for some of the 1,2-unsaturated pyrrolizidine alkaloids, leading to regulatory action on herbal medicinal products with pyrrolizidine alkaloid-containing plants more than 30 years ago. In recent years, it has become evident that in addition to herbal medicinal products containing pyrrolizidine alkaloid-containing plants, these products may also contain pyrrolizidine alkaloids without actually including pyrrolizidine alkaloid-containing plants. This is explained by contamination by accessory herbs (weeds). The national competent authorities of the European member states and the European Medicines Agency, in this case, the Committee on Herbal Medicinal Products, reacted to these findings by setting limits for all herbal medicinal products. This review article will briefly discuss the data leading to the establishment of thresholds and the regulatory developments and consequences, as well as the current discussions and research in this area., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)
- Published
- 2022
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17. Automated mass spectrometry multi-attribute method analyses for process development and characterization of mAbs.
- Author
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Song YE, Dubois H, Hoffmann M, D Eri S, Fromentin Y, Wiesner J, Pfenninger A, Clavier S, Pieper A, Duhau L, and Roth U
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- Animals, CHO Cells, Cricetinae, Cricetulus, Hydrophobic and Hydrophilic Interactions, Research Design, Antibodies, Monoclonal analysis, Antibodies, Monoclonal chemistry, Antibodies, Monoclonal isolation & purification, Antibodies, Monoclonal metabolism, Automation methods, Chromatography, Liquid methods, Mass Spectrometry methods
- Abstract
More than 370 biotherapeutics drug products have been approved by regulatory agencies on the US and EU markets and this industry continues to expand. Process change and optimization is necessary to develop new effective biologics in a cost effective and productive way. Consequently, improvement of analytical techniques is required for better product characterization according to Quality by Design (QbD) approach recommended by regulatory agencies. Recently, multi-attribute method (MAM) has emerged to meet such demands using mass spectrometry coupled to liquid chromatography (LC-MS). However, traditional sample preparation or data processing would not be suitable to guide process development, because one of the common challenges during development of analytical platforms is instrument or method variability which can cause deviation in results. Here, we show a new automated analytical platform for MAM implemented on 3 different sites: the components of MAM platform include automated sample preparation, LC-MS based MAM, and data treatment automation. To our knowledge, this is the first study to show global harmonization on automated MAM platforms and the inter-sites comparability including the automated sample preparation and LC-MS instrument. Also, we demonstrate the applicability of MAM to support cell line development, cell culture process development and downstream process development. We expect that this MAM platform will effectively guide process development across multiple projects., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2021
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18. Tiger beetles (Coleoptera, Cicindelidae) of Northern Mindanao region (Philippines): checklist, distributional maps, and habitats.
- Author
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Acal DAP, Wiesner J, Nuñeza OM, and Jaskuła R
- Abstract
The knowledge about tiger beetle fauna of the Northern Mindanao region (Philippines) is summarized based on literature data and new records. Thirty species classified in ten genera ( Tricondyla , Neocollyris , Protocollyris , Therates , Prothyma , Heptodonta , Thopeutica , Lophyra , Calomera , and Cylindera ) were documented from the area (56% of tiger beetle fauna of Mindanao and 21% of Philippine species). Twelve species were noted from Northern Mindanao region for the first time, including five taxa, Neocollyris speciosa , Calomera angulata , Cylindera minuta , Lophyra striolata tenuiscripta , and Thopeutica virginea , not recorded from Mindanao before. Distribution maps for all recorded species and the first photographs of habitats for some species in Mindanao and/or in the Philippines are provided. Eight species (27% of recorded fauna) were noted from riverine habitats while 18 tiger beetles (60%) were typical forest taxa; in the case of four species, their habitats in Northern Mindanao region are not known., (Dale Ann P. Acal, Jürgen Wiesner, Olga M. Nuñeza, Radomir Jaskuła.)
- Published
- 2021
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19. Alien and native tree species having extrafloral nectaries as favorite hunting area for arboreal endemic Philippine tiger beetles (Coleoptera: Cicindelidae) in human-disturbed habitat in Lanao del Sur Province, Mindanao, Philippines.
- Author
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Marohomsalic JS, Macas Nuñeza O, Michalski M, Wiesner J, and Jaskuła R
- Abstract
To document a relation between abundance of arboreal, predatory tiger beetles, their ant prey, and extrafloral nectaries attracting the ants, we gathered data from more than 10 species of native and introduced trees and large, tree-like perennial plants in Lanao del Sur Province, Mindanao, Philippines. All specimens of tiger beetles (two Tricondyla and two Neocollyris species, all endemic to the country) were noted on five tree species characterized by presence of extrafloral nectaries, including three alien/invasive and two native ones. Invasive Spathodea campanulata and native Hibiscus tiliaceus were the most inhabited ones (respectively, 56% and 19% of beetles). Presence of tiger beetles on these trees most probably depends on high abundance of ants, which are typical prey for arboreal Cicindelidae, while occurrence of ants can result from presence of extrafloral nectaries on different parts of the plants. This suggests a new mutualistic insect-plant interaction between native and invasive species., Competing Interests: All authors declare no conflict of interest including any financial, personal, or other relationships with other people or organizations within 3 years of beginning the submitted work that could inappropriately influence, or be perceived to influence, their work., (© 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)
- Published
- 2021
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20. Versican and Versican-matrikines in Cancer Progression, Inflammation, and Immunity.
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Papadas A, Arauz G, Cicala A, Wiesner J, and Asimakopoulos F
- Subjects
- Extracellular Matrix immunology, Extracellular Matrix pathology, Humans, Neoplasms pathology, Disease Progression, Extracellular Matrix Proteins immunology, Immunity immunology, Inflammation immunology, Neoplasms immunology
- Abstract
Versican is an extracellular matrix proteoglycan with key roles in multiple facets of cancer development, ranging from proliferative signaling, evasion of growth-suppressor pathways, regulation of cell death, promotion of neoangiogenesis, and tissue invasion and metastasis. Multiple lines of evidence implicate versican and its bioactive proteolytic fragments (matrikines) in the regulation of cancer inflammation and antitumor immune responses. The understanding of the dynamics of versican deposition/accumulation and its proteolytic turnover holds potential for the development of novel immune biomarkers as well as approaches to reset the immune thermostat of tumors, thus promoting efficacy of modern immunotherapies. This article summarizes work from several laboratories, including ours, on the role of this central matrix proteoglycan in tumor progression as well as tumor-immune cell cross-talk.
- Published
- 2020
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21. Diagnostic Characteristics of 3-Parameter and 2-Parameter Equations for the Calculation of a Combined Indicator of Vitamin B12 Status to Predict Cobalamin Deficiency in a Large Mixed Patient Population.
- Author
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Campos AJ, Risch L, Nydegger U, Wiesner J, Dyck MVV, Seger C, Stanga Z, Renz H, and Risch M
- Subjects
- Biomarkers, Homocysteine, Humans, Methylmalonic Acid, ROC Curve, Transcobalamins, Vitamin B 12, Vitamin B 12 Deficiency diagnosis
- Abstract
Background: A combined indicator for the determination of vitamin B12 status (4cB12) that employs four markers of vitamin B12 status (i.e., holotranscobalamin, HoloTC; vitamin B12, B12; methyl malonic acid, MMA; and homocysteine, Hcy) has been proposed for the comprehensive assessment of B12 status. We aimed to compare recently published 2- (2cB12) and 3-parameter (3cB12) cB12 equations missing one or two markers of B12 status with the established four-parameter cB12 (4cB12)., Methods: In 3,614 routine samples in which HoloTC, B12, MMA, Hcy and serum folate were measured, cB12 was assessed with 4cB12, as well as with four 3cB12 and six 2cB12 equations. Diagnostic accuracy (AUC) curves were calculated by receiver operating characteristic (ROC) curve analysis with the four-parameter equation (4cB12) as an index. Furthermore, we investigated whether calculating cB12 in addition to a 2-step algorithm employing the same parameters would add diagnostic value for the diagnosis of vitamin B12 deficiency., Results: HoloTC showed the highest diagnostic accuracy among the single markers (AUC = 0.94). The cB12 equation using HoloTC and MMA (2cB12HoloTC/MMA) had the highest AUC among the 2-parameter equations (0.98). Among the 3-parameter equations, 3cB12HoloTC/MMA/Hcy and 3cB12HoloTC/B12/MMA revealed an AUC of 0.99, which was significantly higher than that of 2cB12HoloTC/MMA (p < 0.01). Calculating 2cB12HoloTC/MMA in addition to using a stepwise algorithm employing HoloTC and MMA for diagnosis of vitamin B12 deficiency increased the positive likelihood ratio from 12.1 to 42.6., Conclusions: cB12 calculated with two or three markers of B12 status provides a good approximation of the 4cB12 equation. A 2cB12 equation employing the same parameters improved diagnostic accuracy compared to the use of a 2-step diagnostic algorithm alone. Our results suggest, that laboratories should consider enriching their reports by additionally reporting a corresponding 2cB12 or 3cB12 to results obtained in stepwise diagnostic algorithms.
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- 2020
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22. Antimicrobial Peptides from Rat-Tailed Maggots of the Drone Fly Eristalis tenax Show Potent Activity against Multidrug-Resistant Gram-Negative Bacteria.
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Hirsch R, Wiesner J, Bauer A, Marker A, Vogel H, Hammann PE, and Vilcinskas A
- Abstract
The spread of multidrug-resistant Gram-negative bacteria is an increasing threat to human health, because novel compound classes for the development of antibiotics have not been discovered for decades. Antimicrobial peptides (AMPs) may provide a much-needed breakthrough because these immunity-related defense molecules protect many eukaryotes against Gram-negative pathogens. Recent concepts in evolutionary immunology predict the presence of potent AMPs in insects that have adapted to survive in habitats with extreme microbial contamination. For example, the saprophagous and coprophagous maggots of the drone fly Eristalis tenax (Diptera) can flourish in polluted aquatic habitats, such as sewage tanks and farmyard liquid manure storage pits. We used next-generation sequencing to screen the E. tenax immunity-related transcriptome for AMPs that are synthesized in response to the injection of bacterial lipopolysaccharide. We identified 22 AMPs and selected nine for larger-scale synthesis to test their activity against a broad spectrum of pathogens, including multidrug-resistant Gram-negative bacteria. Two cecropin-like peptides (EtCec1-a and EtCec2-a) and a diptericin-like peptide (EtDip) displayed strong activity against the pathogens, even under simulated physiological conditions, and also achieved a good therapeutic window. Therefore, these AMPs could be used as leads for the development of novel antibiotics., Competing Interests: The authors declare no conflict of interest
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- 2020
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23. Diagnostic Accuracy of Holotranscobalamin, Vitamin B12, Methylmalonic Acid, and Homocysteine in Detecting B12 Deficiency in a Large, Mixed Patient Population.
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Jarquin Campos A, Risch L, Nydegger U, Wiesner J, Vazquez Van Dyck M, Renz H, Stanga Z, and Risch M
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- Adult, Aged, Biomarkers metabolism, Cohort Studies, Female, Humans, Male, Middle Aged, ROC Curve, Retrospective Studies, Sensitivity and Specificity, Vitamin B 12 Deficiency metabolism, Homocysteine metabolism, Methylmalonic Acid metabolism, Transcobalamins metabolism, Vitamin B 12 metabolism, Vitamin B 12 Deficiency diagnosis
- Abstract
Four biomarkers are commonly employed to diagnose B12 deficiency: vitamin B12 (B12), holotranscobalamin (HoloTC), methylmalonic acid (MMA), and homocysteine (Hcy). 4cB12, a combined index of the B12 status, has been suggested to improve the recognition of B12 deficiency. We aimed to evaluate the four different markers for detecting B12 deficiency, as determined by 4cB12. Within a large, mixed patient population, 11,833 samples had concurrent measurements of B12, HoloTC, MMA, and Hcy. 4cB12 was calculated according to the methods described by Fedosov. Diagnostic cutoffs as well as diagnostic accuracy for the detection of B12 deficiency were assessed with receiver operating characteristic (ROC) analysis. The median age was 56 years, and women accounted for 58.8% of the samples. Overall, the area under the curve (AUC) for the detection of subclinical B12 deficiency was highest for HoloTC (0.92), followed by MMA (0.91), B12 (0.9) and Hcy (0.78). The difference between HoloTC and B12 was driven by a significantly higher AUC for HoloTC (0.93) than for B12 (0.89), MMA (0.91), and Hcy in women 50 years and older (0.79; p < 0.05 for all). In the detection of subclinical B12 deficiency, there were no significant differences in the AUCs of HoloTC, B12, and MMA among men and women <50 years. In conclusion, in women < 50 years and in men, HoloTC, MMA, or Hcy do not appear superior to B12 for the detection of B12 deficiency. For women 50 years and older, HoloTC seems to be the preferred first-line marker for the detection of subclinical B12 deficiency., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2020 Araceli Jarquin Campos et al.)
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- 2020
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24. Biological Profiling of Coleoptericins and Coleoptericin-Like Antimicrobial Peptides from the Invasive Harlequin Ladybird Harmonia axyridis.
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Hirsch R, Wiesner J, Marker A, Bauer A, Hammann PE, and Vilcinskas A
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- Animals, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents pharmacology, Humans, Insect Proteins pharmacology, Microbial Sensitivity Tests, Antimicrobial Cationic Peptides pharmacology, Coleoptera chemistry, Gram-Negative Bacteria drug effects
- Abstract
The spread of antibiotic-resistant human pathogens and the declining number of novel antibiotics in the development pipeline is a global challenge that has fueled the demand for alternative options. The search for novel drug candidates has expanded to include not only antibiotics but also adjuvants capable of restoring antibiotic susceptibility in multidrug-resistant (MDR) pathogens. Insect-derived antimicrobial peptides (AMPs) can potentially fulfil both of these functions. We tested two coleoptericins and one coleoptericin-like peptides from the invasive harlequin ladybird Harmonia axyridis against a panel of human pathogens. The AMPs displayed little or no activity when tested alone but were active even against clinical MDR isolates of the Gram-negative ESKAPE strains when tested in combination with polymyxin derivatives, such as the reserve antibiotic colistin, at levels below the minimal inhibitory concentration. Assuming intracellular targets of the AMPs, our data indicate that colistin potentiates the activity of the AMPs. All three AMPs achieved good in vitro therapeutic indices and high intrahepatic stability but low plasma stability, suggesting they could be developed as adjuvants for topical delivery or administration by inhalation for anti-infective therapy to reduce the necessary dose of colistin (and thus its side effects) or to prevent development of colistin resistance in MDR pathogens.
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- 2019
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25. Profiling antimicrobial peptides from the medical maggot Lucilia sericata as potential antibiotics for MDR Gram-negative bacteria.
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Hirsch R, Wiesner J, Marker A, Pfeifer Y, Bauer A, Hammann PE, and Vilcinskas A
- Subjects
- Animals, Anti-Infective Agents adverse effects, Anti-Infective Agents isolation & purification, Antimicrobial Cationic Peptides adverse effects, Antimicrobial Cationic Peptides isolation & purification, Drug-Related Side Effects and Adverse Reactions pathology, Male, Mice, Anti-Infective Agents pharmacology, Antimicrobial Cationic Peptides pharmacology, Diptera chemistry, Drug Resistance, Multiple, Bacterial, Gram-Negative Bacteria drug effects, Larva chemistry
- Abstract
Background: The ability of MDR Gram-negative bacteria to evade even antibiotics of last resort is a severe global challenge. The development pipeline for conventional antibiotics cannot address this issue, but antimicrobial peptides (AMPs) offer an alternative solution., Objectives: Two insect-derived AMPs (LS-sarcotoxin and LS-stomoxyn) were profiled to assess their suitability for systemic application in humans., Methods: The peptides were tested against an extended panel of 114 clinical MDR Gram-negative bacterial isolates followed by time-kill analysis, interaction studies and assays to determine the likelihood of emerging resistance. In further in vitro studies we addressed cytotoxicity, cardiotoxicity and off-target interactions. In addition, an in vivo tolerability and pharmacokinetic study in mice was performed., Results: LS-sarcotoxin and LS-stomoxyn showed potent and selective activity against Gram-negative bacteria and no cross-resistance with carbapenems, fluoroquinolones or aminoglycosides. Peptide concentrations of 4 or 8 mg/L inhibited 90% of the clinical MDR isolates of Escherichia coli, Enterobacter cloacae, Acinetobacter baumannii and Salmonella enterica isolates tested. The 'all-d' homologues of the peptides displayed markedly reduced activity, indicating a chiral target. Pharmacological profiling revealed a good in vitro therapeutic index, no cytotoxicity or cardiotoxicity, an inconspicuous broad-panel off-target profile, and no acute toxicity in mice at 10 mg/kg. In mouse pharmacokinetic experiments LS-sarcotoxin and LS-stomoxyn plasma levels above the lower limit of quantification (1 and 0.25 mg/mL, respectively) were detected after 5 and 15 min, respectively., Conclusions: LS-sarcotoxin and LS-stomoxyn are suitable as lead candidates for the development of novel antibiotics; however, their pharmacokinetic properties need to be improved for systemic administration.
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- 2019
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26. Glycine Amidinotransferase (GATM), Renal Fanconi Syndrome, and Kidney Failure.
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Reichold M, Klootwijk ED, Reinders J, Otto EA, Milani M, Broeker C, Laing C, Wiesner J, Devi S, Zhou W, Schmitt R, Tegtmeier I, Sterner C, Doellerer H, Renner K, Oefner PJ, Dettmer K, Simbuerger JM, Witzgall R, Stanescu HC, Dumitriu S, Iancu D, Patel V, Mozere M, Tekman M, Jaureguiberry G, Issler N, Kesselheim A, Walsh SB, Gale DP, Howie AJ, Martins JR, Hall AM, Kasgharian M, O'Brien K, Ferreira CR, Atwal PS, Jain M, Hammers A, Charles-Edwards G, Choe CU, Isbrandt D, Cebrian-Serrano A, Davies B, Sandford RN, Pugh C, Konecki DS, Povey S, Bockenhauer D, Lichter-Konecki U, Gahl WA, Unwin RJ, Warth R, and Kleta R
- Subjects
- Aged, Amidinotransferases metabolism, Animals, Computer Simulation, Fanconi Syndrome complications, Fanconi Syndrome metabolism, Fanconi Syndrome pathology, Female, Heterozygote, Humans, Infant, Inflammasomes metabolism, Kidney Failure, Chronic etiology, Kidney Failure, Chronic metabolism, Kidney Failure, Chronic pathology, Male, Mice, Mice, Knockout, Molecular Conformation, Mutation, Mutation, Missense, Pedigree, Reactive Oxygen Species metabolism, Sequence Analysis, DNA, Young Adult, Amidinotransferases genetics, Fanconi Syndrome genetics, Kidney Failure, Chronic genetics, Mitochondria metabolism, Mitochondria pathology
- Abstract
Background For many patients with kidney failure, the cause and underlying defect remain unknown. Here, we describe a novel mechanism of a genetic order characterized by renal Fanconi syndrome and kidney failure. Methods We clinically and genetically characterized members of five families with autosomal dominant renal Fanconi syndrome and kidney failure. We performed genome-wide linkage analysis, sequencing, and expression studies in kidney biopsy specimens and renal cells along with knockout mouse studies and evaluations of mitochondrial morphology and function. Structural studies examined the effects of recognized mutations. Results The renal disease in these patients resulted from monoallelic mutations in the gene encoding glycine amidinotransferase (GATM), a renal proximal tubular enzyme in the creatine biosynthetic pathway that is otherwise associated with a recessive disorder of creatine deficiency. In silico analysis showed that the particular GATM mutations, identified in 28 members of the five families, create an additional interaction interface within the GATM protein and likely cause the linear aggregation of GATM observed in patient biopsy specimens and cultured proximal tubule cells. GATM aggregates-containing mitochondria were elongated and associated with increased ROS production, activation of the NLRP3 inflammasome, enhanced expression of the profibrotic cytokine IL-18, and increased cell death. Conclusions In this novel genetic disorder, fully penetrant heterozygous missense mutations in GATM trigger intramitochondrial fibrillary deposition of GATM and lead to elongated and abnormal mitochondria. We speculate that this renal proximal tubular mitochondrial pathology initiates a response from the inflammasome, with subsequent development of kidney fibrosis., (Copyright © 2018 by the American Society of Nephrology.)
- Published
- 2018
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27. Strategies for the construction of insect P450 fusion enzymes.
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Talmann L, Wiesner J, and Vilcinskas A
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- Animals, Biocatalysis, Biotechnology methods, Cytochrome P-450 Enzyme System genetics, Escherichia coli genetics, Insect Proteins genetics, Insecta genetics, NADP metabolism, NADPH-Ferrihemoprotein Reductase genetics, NADPH-Ferrihemoprotein Reductase metabolism, Recombinant Fusion Proteins genetics, Substrate Specificity, Cytochrome P-450 Enzyme System metabolism, Insect Proteins metabolism, Insecta enzymology, Recombinant Fusion Proteins metabolism
- Abstract
Cytochrome P450 monooxygenases (P450s) are ubiquitous enzymes with a broad substrate spectrum. Insect P450s are known to catalyze reactions such as the detoxification of insecticides and the synthesis of hydrocarbons, which makes them useful for many industrial processes. Unfortunately, it is difficult to utilize P450s effectively because they must be paired with cytochrome P450 reductases (CPRs) to facilitate electron transfer from reduced nicotinamide adenine dinucleotide phosphate (NADPH). Furthermore, eukaryotic P450s and CPRs are membrane-anchored proteins, which means they are insoluble and therefore difficult to purify when expressed in their native state. Both challenges can be addressed by creating fusion proteins that combine the P450 and CPR functions while eliminating membrane anchors, allowing the production and purification of soluble multifunctional polypeptides suitable for industrial applications. Here we discuss several strategies for the construction of fusion enzymes combining insect P450 with CPRs.
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- 2017
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28. Herbal medicinal products in pregnancy - which data are available?
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Wiesner J and Knöss W
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- Animals, Female, Humans, Phytotherapy, Pregnancy, Maternal-Fetal Exchange, Plant Preparations therapeutic use
- Abstract
This review aims to highlight recent approaches concerning usage of (traditional) herbal medicinal products in pregnancy and to discuss appropriate strategies to handle limited information. Therefore, published monographs of the Committee on Herbal Medicinal products (HMPC) and selected publicly funded webpages, medicinal handbooks, publications and industry and health care organisations webpages were evaluated. While within the monographs of the HMPC a rather conservative approach could be found (mainly because of lacking nonclinical and/or clinical studies), all other sources display a wide variety of information or assessments, thereby often giving contradictory recommendations. However, some experience with the usage of herbal substances/preparations exists in daily clinical practise without clinical trials or observational studies and some herbal substances/preparations are also used as food/food supplements/cosmetics/medical devices. Discussions should be started how to use that knowledge and experience to adjust regulatory decisions on a case-by-case basis, if possible., (Copyright © 2017 Elsevier Inc. All rights reserved.)
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- 2017
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29. In Vitro Antimicrobial Efficacy of Tobramycin Against Staphylococcus aureus Biofilms in Combination With or Without DNase I and/or Dispersin B: A Preliminary Investigation.
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Waryah CB, Wells K, Ulluwishewa D, Chen-Tan N, Gogoi-Tiwari J, Ravensdale J, Costantino P, Gökçen A, Vilcinskas A, Wiesner J, and Mukkur T
- Subjects
- DNA, Bacterial genetics, Microbial Sensitivity Tests methods, Staphylococcus aureus metabolism, Anti-Bacterial Agents pharmacology, Bacterial Proteins metabolism, Biofilms drug effects, Deoxyribonuclease I metabolism, Staphylococcus aureus drug effects, Tobramycin pharmacology
- Abstract
Staphylococcus aureus in biofilms is highly resistant to the treatment with antibiotics, to which the planktonic cells are susceptible. This is likely to be due to the biofilm creating a protective barrier that prevents antibiotics from accessing the live pathogens buried in the biofilm. S. aureus biofilms consist of an extracellular matrix comprising, but not limited to, extracellular bacterial DNA (eDNA) and poly-β-1, 6-N-acetyl-d-glucosamine (PNAG). Our study revealed that despite inferiority of dispersin B (an enzyme that degrades PNAG) to DNase I that cleaves eDNA, in dispersing the biofilm of S. aureus, both enzymes were equally efficient in enhancing the antibacterial efficiency of tobramycin, a relatively narrow-spectrum antibiotic against infections caused by gram-positive and gram-negative pathogens, including S. aureus, used in this investigation. However, a combination of these two biofilm-degrading enzymes was found to be significantly less effective in enhancing the antimicrobial efficacy of tobramycin than the individual application of the enzymes. These findings indicate that combinations of different biofilm-degrading enzymes may compromise the antimicrobial efficacy of antibiotics and need to be carefully assessed in vitro before being used for treating medical devices or in pharmaceutical formulations for use in the treatment of chronic ear or respiratory infections.
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- 2017
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30. Re-evaluation of guar gum (E 412) as a food additive.
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Mortensen A, Aguilar F, Crebelli R, Di Domenico A, Frutos MJ, Galtier P, Gott D, Gundert-Remy U, Lambré C, Leblanc JC, Lindtner O, Moldeus P, Mosesso P, Oskarsson A, Parent-Massin D, Stankovic I, Waalkens-Berendsen I, Woutersen RA, Wright M, Younes M, Brimer L, Peters P, Wiesner J, Christodoulidou A, Lodi F, Tard A, and Dusemund B
- Abstract
The Panel on Food Additives and Nutrient Sources added to Food (ANS) provides a scientific opinion re-evaluating the safety of guar gum (E 412) as a food additive. In the EU, guar gum was evaluated by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 1970, 1974 and 1975, who allocated an acceptable daily intake (ADI) 'not specified'. Guar gum has been also evaluated by the Scientific Committee for Food (SCF) in 1977 who endorsed the ADI 'not specified' allocated by JECFA. Following the conceptual framework for the risk assessment of certain food additives re-evaluated under Commission Regulation (EU) No 257/2010, the Panel considered that adequate exposure and toxicity data were available. Guar gum is practically undigested, not absorbed intact, but significantly fermented by enteric bacteria in humans. No adverse effects were reported in subchronic and carcinogenicity studies at the highest dose tested; no concern with respect to the genotoxicity. Oral intake of guar gum was well tolerated in adults. The Panel concluded that there is no need for a numerical ADI for guar gum (E 412), and there is no safety concern for the general population at the refined exposure assessment of guar gum (E 412) as a food additive. The Panel considered that for uses of guar gum in foods intended for infants and young children the occurrence of abdominal discomfort should be monitored and if this effect is observed doses should be identified as a basis for further risk assessment. The Panel considered that no adequate specific studies addressing the safety of use of guar gum (E 412) in food categories 13.1.5.1 and 13.1.5.2 were available. Therefore, the Panel concluded that the available data do not allow an adequate assessment of the safety of guar gum (E 412) in infants and young children consuming these foods for special medical purposes., (© 2017 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)
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- 2017
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31. Re-evaluation of locust bean gum (E 410) as a food additive.
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Mortensen A, Aguilar F, Crebelli R, Di Domenico A, Frutos MJ, Galtier P, Gott D, Gundert-Remy U, Lambré C, Leblanc JC, Lindtner O, Moldeus P, Mosesso P, Oskarsson A, Parent-Massin D, Stankovic I, Waalkens-Berendsen I, Woutersen RA, Wright M, Younes M, Brimer L, Peters P, Wiesner J, Christodoulidou A, Lodi F, Tard A, and Dusemund B
- Abstract
Following a request from European Commission, the EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS) provides a scientific opinion re-evaluating the safety of locust bean gum (E 410) as a food additive. Locust bean gum (E 410) is an authorised food additive in the EU. Locust bean gum (E 410) as specified in the Commission Regulation (EU) No 231/2012 is derived from the ground endosperm of the seeds of the strains of carob tree, Ceratonia siliqua (L.) Taub. (Family Leguminosae). An acceptable daily intake (ADI) 'not specified' was allocated by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (JECFA) in 1981. Although not evaluated by the Scientific Committee for Food (SCF), it was accepted by the SCF in 1991 for use in weaning food, and in 1994, in infant formulae for special medical purposes. Locust bean gum is practically undigested, not absorbed intact, but significantly fermented by enteric bacteria in humans. No adverse effects were reported in 90-day toxicity and carcinogenicity studies in rodents at the highest doses tested and there was no concern with respect to the genotoxicity and to reproductive and developmental toxicity of locust bean gum (E 410). The Panel concluded that there is no need for a numerical ADI for locust bean gum (E 410), and that there is no safety concern for the general population at the refined exposure assessment for its reported uses as a food additive. However, infants and young children consuming foods for special medical purposes may show a higher susceptibility to gastrointestinal effects of locust bean gum due to their underlying medical condition. The Panel concluded that the available data do not allow an adequate assessment of the safety of locust bean gum (E 410) in these foods for infants and young children., (© 2017 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)
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- 2017
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32. FR-900098, an antimalarial development candidate that inhibits the non-mevalonate isoprenoid biosynthesis pathway, shows no evidence of acute toxicity and genotoxicity.
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Wiesner J, Ziemann C, Hintz M, Reichenberg A, Ortmann R, Schlitzer M, Fuhst R, Timmesfeld N, Vilcinskas A, and Jomaa H
- Subjects
- Administration, Intravenous, Animals, Antimalarials administration & dosage, Drug Discovery, Erythrocytes drug effects, Fosfomycin administration & dosage, Fosfomycin toxicity, Male, Mice, Mutagenicity Tests, Rats, Salmonella typhimurium drug effects, Salmonella typhimurium genetics, Antimalarials toxicity, DNA Damage, Fosfomycin analogs & derivatives
- Abstract
FR-900098 is an inhibitor of 1-deoxy-d-xylulose-5-phosphate (DXP) reductoisomerase, the second enzyme in the non-mevalonate isoprenoid biosynthesis pathway. In previous studies, FR-900098 was shown to possess potent antimalarial activity in vitro and in a murine malaria model. In order to provide a basis for further preclinical and clinical development, we studied the acute toxicity and genotoxicity of FR-900098. We observed no acute toxicity in rats, i.e. there were no clinical signs of toxicity and no substance-related deaths after the administration of a single dose of 3000 mg/kg body weight orally or 400 mg/kg body weight intravenously. No mutagenic potential was detected in the Salmonella typhimurium reverse mutation assay (Ames test) or an in vitro mammalian cell gene mutation test using mouse lymphoma L5178Y/TK(+/-) cells (clone 3.7.2C), both with and without metabolic activation. In addition, FR-900098 demonstrated no clastogenic or aneugenic capability or significant adverse effects on blood formation in an in vivo micronucleus test with bone marrow erythrocytes from NMRI mice. We conclude that FR-900098 lacks acute toxicity and genotoxicity, supporting its further development as an antimalarial drug.
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- 2016
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33. Expression and characterization of a recombinant i-type lysozyme from the harlequin ladybird beetle Harmonia axyridis.
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Beckert A, Wiesner J, Schmidtberg H, Lehmann R, Baumann A, Vogel H, and Vilcinskas A
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- Amino Acid Sequence, Animals, Carbon-Nitrogen Lyases analysis, Coleoptera genetics, Coleoptera immunology, Immunity, Innate, Molecular Sequence Data, Muramidase genetics, Pichia, Coleoptera enzymology, Muramidase metabolism
- Abstract
Lysozymes are enzymes that destroy bacterial cell walls by hydrolysing the polysaccharide component of peptidoglycan. In insects, there are two classes of lysozymes, the c-type with muramidase activity and the i-type whose prototypical members from annelids and molluscs possess both muramidase and isopeptidase activities. Many insect genes encoding c-type and i-type lysozymes have been identified during genome and transcriptome analyses, but only c-type lysozymes have been functionally characterized at the protein level. Here we produced one of five i-type lysozymes represented in the immunity-related transcriptome of the invasive harlequin ladybird beetle Harmonia axyridis as recombinant protein. This was the only one containing the serine and histidine residues that are thought to be required for isopeptidase activity. This i-type lysozyme was recombinantly expressed in the yeast Pichia pastoris, but the purified protein was inactive in both muramidase and isopeptidase assays. Transcription and immunofluorescence analysis revealed that this i-type lysozyme is produced in the fat body but is not inducible by immune challenge. These data suggest that i-type lysozymes in insects may have acquired novel and as yet undetermined functions in the course of evolution., (© 2016 The Royal Entomological Society.)
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- 2016
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34. A Jonah-like chymotrypsin from the therapeutic maggot Lucilia sericata plays a role in wound debridement and coagulation.
- Author
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Pöppel AK, Kahl M, Baumann A, Wiesner J, Gökçen A, Beckert A, Preissner KT, Vilcinskas A, and Franta Z
- Subjects
- Amino Acid Sequence, Animals, Chromatography, Affinity, Chymotrypsin chemistry, Chymotrypsin genetics, Drosophila melanogaster genetics, Humans, Molecular Sequence Data, Recombinant Proteins chemistry, Recombinant Proteins genetics, Recombinant Proteins metabolism, Blood Coagulation, Chymotrypsin metabolism, Debridement methods, Larva enzymology
- Abstract
Lucilia sericata larvae are used in maggot debridement therapy, a traditional wound healing approach that has recently been approved for the treatment of chronic wounds. Maggot excretion products (MEP) contain many different proteases that promote disinfection, debridement and the acceleration of wound healing, e.g. by activating the host contact phase/intrinsic pathway of coagulation. In order to characterise relevant procoagulant proteases, we analysed MEP and identified a chymotrypsin-like serine protease with similarities to Jonah proteases from Drosophila melanogaster and a chymotrypsin from Lucilia cuprina. A recombinant form of the L. sericata Jonah chymotrypsin was produced in Escherichia coli. The activated enzyme (Jonahm) had a pH optimum of 8.0 and a temperature optimum of 37 °C, based on the cleavage of the chromogenic peptide s-7388 and casein. Jonahm reduced the clotting time of human plasma even in the absence of the endogenous protease kallikrein, factor XI or factor XII and digested the extracellular matrix proteins fibronectin, laminin and collagen IV, suggesting a potential mechanism of wound debridement. Based on these characteristics, the novel L. sericata chymotrypsin-like serine protease appears to be an ideal candidate for the development of topical drugs for wound healing applications., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
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- 2016
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35. Molecular mechanism of thermosensory function of human heat shock transcription factor Hsf1.
- Author
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Hentze N, Le Breton L, Wiesner J, Kempf G, and Mayer MP
- Subjects
- Heat Shock Transcription Factors, Humans, Kinetics, Mass Spectrometry, Protein Conformation radiation effects, Protein Folding radiation effects, DNA-Binding Proteins chemistry, DNA-Binding Proteins metabolism, Protein Multimerization radiation effects, Temperature, Transcription Factors chemistry, Transcription Factors metabolism
- Abstract
The heat shock response is a universal homeostatic cell autonomous reaction of organisms to cope with adverse environmental conditions. In mammalian cells, this response is mediated by the heat shock transcription factor Hsf1, which is monomeric in unstressed cells and upon activation trimerizes, and binds to promoters of heat shock genes. To understand the basic principle of Hsf1 activation we analyzed temperature-induced alterations in the conformational dynamics of Hsf1 by hydrogen exchange mass spectrometry. We found a temperature-dependent unfolding of Hsf1 in the regulatory region happening concomitant to tighter packing in the trimerization region. The transition to the active DNA binding-competent state occurred highly cooperative and was concentration dependent. Surprisingly, Hsp90, known to inhibit Hsf1 activation, lowered the midpoint temperature of trimerization and reduced cooperativity of the process thus widening the response window. Based on our data we propose a kinetic model of Hsf1 trimerization.
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- 2016
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36. Maggot excretion products from the blowfly Lucilia sericata contain contact phase/intrinsic pathway-like proteases with procoagulant functions.
- Author
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Kahl M, Gökçen A, Fischer S, Bäumer M, Wiesner J, Lochnit G, Wygrecka M, Vilcinskas A, and Preissner KT
- Subjects
- Animals, Blood Coagulation Factors drug effects, Blood Coagulation Factors metabolism, Blood Coagulation Tests, Complement C1 Inhibitor Protein metabolism, Complement C1 Inhibitor Protein pharmacology, Debridement, Diptera growth & development, Enzyme Activation drug effects, Factor XIIa biosynthesis, Feces, Insect Proteins isolation & purification, Kallikreins blood, Larva enzymology, Nephelometry and Turbidimetry, Platelet Aggregation drug effects, Protease Inhibitors pharmacology, Serine Proteases isolation & purification, Thrombelastography, Wound Healing, Blood Coagulation drug effects, Diptera enzymology, Insect Proteins pharmacology, Serine Proteases pharmacology
- Abstract
For centuries, maggots have been used for the treatment of wounds by a variety of ancient cultures, as part of their traditional medicine. With increasing appearance of antimicrobial resistance and in association with diabetic ulcers, maggot therapy was revisited in the 1980s. Three mechanisms by which sterile maggots of the green bottle fly Lucilia sericata may improve healing of chronic wounds have been proposed: Biosurgical debridement, disinfecting properties, and stimulation of the wound healing process. However, the influence of maggot excretion products (MEP) on blood coagulation as part of the wound healing process has not been studied in detail. Here, we demonstrate that specific MEP-derived serine proteases from Lucilia sericata induce clotting of human plasma and whole blood, particularly by activating contact phase proteins factor XII and kininogen as well as factor IX, thereby providing kallikrein-bypassing and factor XIa-like activities, both in plasma and in isolated systems. In plasma samples deficient in contact phase proteins, MEP restored full clotting activity, whereas in plasma deficient in either factor VII, IX, X or II no effect was seen. The observed procoagulant/intrinsic pathway-like activity was mediated by (chymo-) trypsin-like proteases in total MEP, which were significantly blocked by C1-esterase inhibitor or other contact phase-specific protease inhibitors. No significant influence of MEP on platelet activation or fibrinolysis was noted. Together, MEP provides contact phase bypassing procoagulant activity and thereby induces blood clotting in the context of wound healing. Further characterisation of the active serine protease(s) may offer new perspectives for biosurgical treatment of chronic wounds.
- Published
- 2015
- Full Text
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37. Insect antimicrobial peptides show potentiating functional interactions against Gram-negative bacteria.
- Author
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Rahnamaeian M, Cytryńska M, Zdybicka-Barabas A, Dobslaff K, Wiesner J, Twyman RM, Zuchner T, Sadd BM, Regoes RR, Schmid-Hempel P, and Vilcinskas A
- Subjects
- Amino Acid Sequence, Animals, Antimicrobial Cationic Peptides metabolism, Escherichia coli metabolism, Insect Proteins metabolism, Sequence Alignment, Species Specificity, Anti-Infective Agents metabolism, Antimicrobial Cationic Peptides genetics, Bees immunology, Bees microbiology, Insect Proteins genetics
- Abstract
Antimicrobial peptides (AMPs) and proteins are important components of innate immunity against pathogens in insects. The production of AMPs is costly owing to resource-based trade-offs, and strategies maximizing the efficacy of AMPs at low concentrations are therefore likely to be advantageous. Here, we show the potentiating functional interaction of co-occurring insect AMPs (the bumblebee linear peptides hymenoptaecin and abaecin) resulting in more potent antimicrobial effects at low concentrations. Abaecin displayed no detectable activity against Escherichia coli when tested alone at concentrations of up to 200 μM, whereas hymenoptaecin affected bacterial cell growth and viability but only at concentrations greater than 2 μM. In combination, as little as 1.25 μM abaecin enhanced the bactericidal effects of hymenoptaecin. To understand these potentiating functional interactions, we investigated their mechanisms of action using atomic force microscopy and fluorescence resonance energy transfer-based quenching assays. Abaecin was found to reduce the minimal inhibitory concentration of hymenoptaecin and to interact with the bacterial chaperone DnaK (an evolutionarily conserved central organizer of the bacterial chaperone network) when the membrane was compromised by hymenoptaecin. These naturally occurring potentiating interactions suggest that combinations of AMPs could be used therapeutically against Gram-negative bacterial pathogens that have acquired resistance to common antibiotics.
- Published
- 2015
- Full Text
- View/download PDF
38. Antimicrobial peptides expressed in medicinal maggots of the blow fly Lucilia sericata show combinatorial activity against bacteria.
- Author
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Pöppel AK, Vogel H, Wiesner J, and Vilcinskas A
- Subjects
- Animals, Anti-Bacterial Agents chemistry, Anti-Infective Agents chemistry, Anti-Infective Agents metabolism, Escherichia coli drug effects, Larva genetics, Larva metabolism, Microbial Sensitivity Tests, Micrococcus luteus drug effects, Molecular Sequence Data, Peptides chemistry, Peptides genetics, Peptides pharmacology, Proteus vulgaris drug effects, Pseudomonas aeruginosa drug effects, Anti-Bacterial Agents metabolism, Anti-Bacterial Agents pharmacology, Anti-Infective Agents pharmacology, Diptera genetics, Diptera metabolism
- Abstract
The larvae of the common green bottle fly (Lucilia sericata) produce antibacterial secretions that have a therapeutic effect on chronic and nonhealing wounds. Recent developments in insect biotechnology have made it possible to use these larvae as a source of novel anti-infectives. Here, we report the application of next-generation RNA sequencing (RNA-Seq) to characterize the transcriptomes of the larval glands, crop, and gut, which contribute to the synthesis of antimicrobial peptides (AMPs) and proteins secreted into wounds. Our data confirm that L. sericata larvae have adapted in order to colonize microbially contaminated habitats, such as carrion and necrotic wounds, and are protected against infection by a diverse spectrum of AMPs. L. sericata AMPs include not only lucifensin and lucimycin but also novel attacins, cecropins, diptericins, proline-rich peptides, and sarcotoxins. We identified 47 genes encoding putative AMPs and produced 23 as synthetic analogs, among which some displayed activities against a broad spectrum of microbial pathogens, including Pseudomonas aeruginosa, Proteus vulgaris, and Enterococcus faecalis. Against Escherichia coli (Gram negative) and Micrococcus luteus (Gram positive), we found mostly additive effects but also synergistic activity when selected AMPs were tested in combination. The AMPs that are easy to synthesize are currently being produced in bulk to allow their evaluation as novel anti-infectives that can be formulated in hydrogels to produce therapeutic wound dressings and adhesive bandages., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)
- Published
- 2015
- Full Text
- View/download PDF
39. Two c-type lysozymes boost the innate immune system of the invasive ladybird Harmonia axyridis.
- Author
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Beckert A, Wiesner J, Baumann A, Pöppel AK, Vogel H, and Vilcinskas A
- Subjects
- Amino Acid Sequence, Animals, Antimicrobial Cationic Peptides genetics, Calcium metabolism, Coleoptera genetics, Gastrointestinal Tract enzymology, Gene Expression genetics, Gene Expression immunology, Hemolymph enzymology, Hemolymph metabolism, Immunity, Innate, Microbial Sensitivity Tests, Muramidase genetics, Muramidase metabolism, Pichia enzymology, Pichia metabolism, Recombinant Proteins pharmacology, Sequence Alignment, Sequence Analysis, DNA, Up-Regulation, Anti-Bacterial Agents metabolism, Bacillus subtilis drug effects, Coleoptera immunology, Gastrointestinal Tract immunology, Muramidase immunology
- Abstract
The invasive ladybird beetle Harmonia axyridis has a two-layered immune system, featuring the constitutive production of the low-molecular-mass antimicrobial compound harmonine and the inducible production of a broad range of antimicrobial peptides (AMPs). Here we show that the immune system also features two c-type lysozymes, the acidic c-lys3 (pI = 5.46) and the basic c-lys4 (pI = 8.18). The injection of bacteria into H.axyridis boosted c-lys4 gene expression 8-fold in the gut, whereas the c-lys3 gene was expressed at comparable levels in both naïve and challenged beetles. Both c-lys3 and c-lys4 were expressed in Pichia pastoris and the bacteriolytic activity of the recombinant proteins was found to be calcium-dependent with pH maxima of 6.0 and 6.5, respectively. In a Bacillus subtilis growth inhibition assay, the antimicrobial activity of harmonine and two highly-inducible H.axyridis AMPs (coleoptericins) was potentiated in the presence of c-lys4 but not c-lys3, resulting in 4-fold (harmonine) and up to 16-fold (AMP) lower minimum inhibitory concentrations. Our results suggest that two structurally and functionally distinct lysozymes contribute to innate immune responses of H.axyridis and augment the harmonine and AMP components of the immune response., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2015
- Full Text
- View/download PDF
40. Advanced mass spectrometry workflows for analyzing disulfide bonds in biologics.
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Wiesner J, Resemann A, Evans C, Suckau D, and Jabs W
- Subjects
- Humans, Proteins therapeutic use, Recombinant Proteins chemistry, Recombinant Proteins therapeutic use, Disulfides chemistry, Mass Spectrometry methods, Proteins chemistry
- Abstract
Proteins are an important class of biologics. Their higher-order structures and therefore their functions are fundamentally determined by the correct formation of disulfide bonds (DSBs), making DSB analysis a central part of their development and production. Mass spectrometry-based bottom-up approaches are most widely used and are further classified according to different methods applied for DSB cleavage. Despite the importance of DSB analysis and the wide range of available methodologies, it is often a challenging and time consuming task. However, due to the current increase in biosimilar development in which animal and clinical trials can be reduced by extensive analytical comparability studies, increased efforts are being made to simplify DSB analysis. As an example of these developments, a matrix-assisted laser desorption/ionization time-of-flight (TOF)/TOF workflow for the automated profiling and identification of DSBs is presented. Furthermore, mass spectrometry based methodologies, which do not identify DSBs directly but measure their influence on the higher-order structure, are also considered.
- Published
- 2015
- Full Text
- View/download PDF
41. Challenges of safety evaluation.
- Author
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Wiesner J
- Subjects
- Drug Approval legislation & jurisprudence, European Union, Humans, Medicine, Traditional standards, Phytotherapy standards, Plant Preparations standards, Legislation, Drug, Medicine, Traditional adverse effects, Phytotherapy adverse effects, Plant Preparations adverse effects
- Abstract
Each application for authorisation of a medicinal product must be accompanied by the particulars and documents referred to in Directive 2001/83/EC on the Community code relating to medicinal products for human use. Details on the documentation needed for traditional herbal medicinal products (THMP) are given in article 16c of the above mentioned Directive. It is pointed out that a bibliographic review of safety data together with an expert report and additional data, if necessary, are required. The Committee on Herbal Medicinal Products (HMPC) provides in its "Guideline on the use of the CTD format in the preparation of a registration application for traditional herbal medicinal products" (EMA/HMPC/71049/2007 Rev. 1) guidance on how to present the information and the dossier needed for an application. There, in agreement with the Directive 2001/83/EC, a bibliographical review of safety data is required within the "Non-clinical Overview". However, it is assumable that for such products, with a long tradition of usage bibliographical information relating to non-clinical safety are available, even if incomplete or not in accordance with today׳s state of the art. In the "Guideline on non-clinical documentation for herbal medicinal products in applications for marketing authorisation (bibliographical and mixed applications) and in applications for simplified registration" (EMEA/HMPC/32116/2005) it is reflected how to deal with such an incomplete set of data for traditional herbal medicinal products and crucial information are highlighted. This article will focus on the explanation of the requirements needed for the non-clinical safety evaluation of THMPs and some detailed explanations of the performance and interpretation of the mutagenicity studies., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
42. Future visions for traditional and herbal medicinal products--a global practice for evaluation and regulation?
- Author
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Wiesner J and Knöss W
- Subjects
- Humans, International Cooperation, Medicine, Traditional trends, Phytotherapy trends, Plant Preparations standards, Risk Management methods, Terminology as Topic, Legislation, Drug, Medicine, Traditional standards, Phytotherapy standards
- Abstract
Medicinal plants and traditional medicines have been used worldwide since ancient times. Currently, there is neither a globally consented terminology nor a harmonized regulatory approach. Nevertheless, it is common sense that quality, efficacy and safety should be assessed following scientific standards, addressing particulars and considering an adequate level of risk management. A global market for traditional medicines is emerging, if not already existing. Therefore, a constructive communication about regulatory systems for herbal and traditional medicinal products should be enforced. Best practice standards might be developed according to current scientific knowledge in order to improve mutual acceptance of data, sets of monographs and assessments. Overall, a convergence of the diverse regulatory systems might save resources and lead to an adequate availability of herbal and traditional medicinal products to the patients without neglecting public health., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
43. Assessment of genotoxicity of herbal medicinal products: application of the "bracketing and matrixing" concept using the example of Valerianae radix (valerian root).
- Author
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Kelber O, Wegener T, Steinhoff B, Staiger C, Wiesner J, Knöss W, and Kraft K
- Subjects
- DNA Damage, Herbal Medicine methods, Humans, Medicine, Traditional, Mutagenicity Tests, Plant Roots chemistry, Plants, Medicinal, Quality Control, Consumer Product Safety standards, Phytotherapy standards, Plant Preparations standards, Valerian chemistry
- Abstract
An assessment of genotoxicity is a precondition for marketing authorization respectively registration of herbal medicinal products (HMPs), as well as for inclusion into the 'Community list of herbal substances, preparations and combinations thereof for use in traditional herbal medicinal products' established by the European Commission in accordance with Directive 2001/83/EC as amended, and based on proposals from the Committee on Herbal Medicinal Products (HMPC). In the 'Guideline on the assessment of genotoxicity of herbal substances/preparations' (EMEA/HMPC/107079/2007) HMPC has described a stepwise approach for genotoxicity testing, according to which the Ames test is a sufficient base for the assessment of genotoxicity in case of an unequivocally negative result. For reducing efforts for testing of individual herbal substances/preparations, HMPC has also developed the 'guideline on selection of test materials for genotoxicity testing for traditional herbal medicinal products/herbal medicinal products' (EMEA/HMPC/67644/2009) with the aim to allow testing of a standard range of test materials which could be considered representative of the commonly used preparations from a specific herbal drug according to a 'bracketing/matrixing' approach. The purpose of this paper is to provide data on the practical application of this bracketing and matrixing concept using the example of Valerianae radix, with the intention of facilitating its inclusion in the "Community list". Five extraction solvents, representing the extremes of the polarity range and including also mid-range extraction solvents, were used, covering the entire spectrum of phytochemical constituents of Valerianae radix, thereby including polar and non-polar constituents. Extracts were tested in the Ames test according to all relevant guidelines. Results were unequivocally negative for all extracts. A review of the literature showed that this result is in accordance with the available data, thus demonstrating the lack of a genotoxic potential. In conclusion the two guidelines on genotoxicity provide a practically applicable concept. Valerianae radix has no genotoxic potential, supporting its use in HMPs and its inclusion in the Community list., (Copyright © 2014 The Authors. Published by Elsevier GmbH.. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
44. Lucimycin, an antifungal peptide from the therapeutic maggot of the common green bottle fly Lucilia sericata.
- Author
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Pöppel AK, Koch A, Kogel KH, Vogel H, Kollewe C, Wiesner J, and Vilcinskas A
- Subjects
- Animals, Larva, Sequence Analysis, Protein, Antifungal Agents metabolism, Lucensomycin metabolism, Peptides metabolism
- Abstract
We report the identification, cloning, heterologous expression and functional characterization of a novel antifungal peptide named lucimycin from the common green bottle fly Lucilia sericata. The lucimycin cDNA was isolated from a library of genes induced during the innate immune response in L. sericata larvae, which are used as therapeutic maggots. The peptide comprises 77 amino acid residues with a molecular mass of 8.2 kDa and a pI of 6.6. It is predicted to contain a zinc-binding motif and to form a random coil, lacking β-sheets or other secondary structures. Lucimycin was active against fungi from the phyla Ascomycota, Basidiomycota and Zygomycota, in addition to the oomycete Phytophtora parasitica, but it was inactive against bacteria. A mutant version of lucimycin, lacking the four C-terminal amino acid residues, displayed 40-fold lower activity. The activity of lucimycin against a number of highly-destructive plant pathogens could be exploited to produce transgenic crops that are resistant against fungal diseases.
- Published
- 2014
- Full Text
- View/download PDF
45. Biofilm-degrading enzymes from Lysobacter gummosus.
- Author
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Gökçen A, Vilcinskas A, and Wiesner J
- Subjects
- Mass Spectrometry, Peptide Hydrolases chemistry, Peptide Hydrolases isolation & purification, Staphylococcus epidermidis growth & development, Antibiosis, Biofilms drug effects, Biofilms growth & development, Lysobacter enzymology, Peptide Hydrolases metabolism, Staphylococcus epidermidis drug effects, Staphylococcus epidermidis physiology
- Abstract
Biofilm-degrading enzymes could be used for the gentle cleaning of industrial and medical devices and the manufacture of biofilm-resistant materials. We therefore investigated 20 species and strains of the bacterial genus Lysobacter for their ability to degrade experimental biofilms formed by Staphylococcus epidermidis, a common nosocomial pathogen typically associated with device-related infections. The highest biofilm-degradation activity was achieved by L. gummosus. The corresponding enzymes were identified by sequencing the L. gummosus genome. Partial purification of the biofilm-degrading activity from an extract of extracellular material followed by peptide mass fingerprinting resulted in the identification of two peptidases (α-lytic protease and β-lytic metalloendopeptidase) that were predicted to degrade bacterial cell walls. In addition, we identified two isoforms of a lysyl endopeptidase and an enzyme similar to metalloproteases from Vibrio spp. Potential peptidoglycan-binding C-terminal fragments of two OmpA-like proteins also co-purified with the biofilm-degrading activity. The L. gummosus genome was found to encode five isoenzymes of α-lytic protease and three isoenzymes of lysyl endopeptidase. These results indicated that the extracellular digestion of biofilms by L. gummosus depends on multiple bacteriolytic and proteolytic enzymes, which could now be exploited for biofilm control.
- Published
- 2014
- Full Text
- View/download PDF
46. Structure of the (E)-4-hydroxy-3-methyl-but-2-enyl-diphosphate reductase from Plasmodium falciparum.
- Author
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Rekittke I, Olkhova E, Wiesner J, Demmer U, Warkentin E, Jomaa H, and Ermler U
- Subjects
- Catalytic Domain, Crystallography, X-Ray, Escherichia coli enzymology, Escherichia coli metabolism, Ferredoxins metabolism, Models, Molecular, Molecular Docking Simulation, Plasmodium falciparum metabolism, Protein Binding, Protein Conformation, Protein Folding, Protozoan Proteins chemistry, Protozoan Proteins metabolism, Organophosphorus Compounds metabolism, Oxidoreductases chemistry, Oxidoreductases metabolism, Plasmodium falciparum enzymology
- Abstract
Terpenoid precursor biosynthesis occurs in human and many pathogenic organisms via the mevalonate and 2-C-methyl-d-erythritol-4-phosphate (MEP) pathways, respectively. We determined the X-ray structure of the Fe/S containing (E)-4-hydroxy-3-methyl-but-2-enyl-diphosphate reductase (LytB) of the pathogenic protozoa Plasmodium falciparum which catalyzes the terminal step of the MEP pathway. The cloverleaf fold and the active site of P. falciparum LytB corresponds to those of the Aquifex aeolicus and Escherichia coli enzymes. Its distinct electron donor [2Fe-2S] ferredoxin was modeled to its binding site by docking calculations. The presented structural data provide a platform for a rational search of anti-malarian drugs., (© 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.)
- Published
- 2013
- Full Text
- View/download PDF
47. Changes in the transcriptome of the malaria parasite Plasmodium falciparum during the initial phase of transmission from the human to the mosquito.
- Author
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Ngwa CJ, Scheuermayer M, Mair GR, Kern S, Brügl T, Wirth CC, Aminake MN, Wiesner J, Fischer R, Vilcinskas A, and Pradel G
- Subjects
- Animals, Gene Expression Regulation, Gene Library, Genes, Protozoan genetics, Humans, Insect Vectors genetics, Protozoan Proteins genetics, Gametogenesis genetics, Malaria, Falciparum transmission, Plasmodium falciparum genetics, Protozoan Proteins biosynthesis, Transcriptome
- Abstract
Background: The transmission of the malaria parasite Plasmodium falciparum from the human to the mosquito is mediated by dormant sexual precursor cells, the gametocytes, which become activated in the mosquito midgut. Because gametocytes are the only parasite stages able to establish an infection in the mosquito, they play a crucial role in spreading the tropical disease. The human-to-mosquito transmission triggers important molecular changes in the gametocytes, which initiate gametogenesis and prepare the parasite for life-cycle progression in the insect vector., Results: To better understand gene regulations during the initial phase of malaria parasite transmission, we focused on the transcriptome changes that occur within the first half hour of parasite development in the mosquito. Comparison of mRNA levels of P. falciparum gametocytes before and 30 min following activation using suppression subtractive hybridization (SSH) identified 126 genes, which changed in expression during gametogenesis. Among these, 17.5% had putative functions in signaling, 14.3% were assigned to cell cycle and gene expression, 8.7% were linked to the cytoskeleton or inner membrane complex, 7.9% were involved in proteostasis and 6.4% in metabolism, 12.7% were cell surface-associated proteins, 11.9% were assigned to other functions, and 20.6% represented genes of unknown function. For 40% of the identified genes there has as yet not been any protein evidence.For a subset of 27 genes, transcript changes during gametogenesis were studied in detail by real-time RT-PCR. Of these, 22 genes were expressed in gametocytes, and for 15 genes transcript expression in gametocytes was increased compared to asexual blood stage parasites. Transcript levels of seven genes were particularly high in activated gametocytes, pointing at functions downstream of gametocyte transmission to the mosquito. For selected genes, a regulated expression during gametogenesis was confirmed on the protein level, using quantitative confocal microscopy., Conclusions: The obtained transcriptome data demonstrate the regulations of gene expression immediately following malaria parasite transmission to the mosquito. Our findings support the identification of proteins important for sexual reproduction and further development of the mosquito midgut stages and provide insights into the genetic basis of the rapid adaption of Plasmodium to the insect vector.
- Published
- 2013
- Full Text
- View/download PDF
48. Methods to identify enzymes that degrade the main extracellular polysaccharide component of Staphylococcus epidermidis biofilms.
- Author
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Gökçen A, Vilcinskas A, and Wiesner J
- Subjects
- Chromatography, Ion Exchange instrumentation, Glycoside Hydrolases metabolism, Polysaccharides metabolism, Spectrometry, Mass, Electrospray Ionization instrumentation, Staphylococcus epidermidis chemistry, Biofilms, Chromatography, Ion Exchange methods, Glycoside Hydrolases chemistry, Polysaccharides chemistry, Spectrometry, Mass, Electrospray Ionization methods, Staphylococcus epidermidis metabolism
- Abstract
The production of extracellular poly-β-1,6-N-acetyl-D-glucosamine (PNAG) by Staphylococcus epidermidis is the principal determinant of biofilm formation on indwelling medical devices. Enzymes that degrade PNAG therefore provide an attractive strategy for biofilm removal and for the manufacture of biofilm-resistant coatings. Here we present methods that allow the identification of PNAG-degrading enzymes with the ability to detach biofilms. Our protocol includes the preparation of soluble PNAG from S. epidermidis cultures, the incubation of soluble PNAG with candidate enzymes and assays that detect the release of N-acetyl-D-glucosamine using high-pH anion-exchange chromatography (HPAEC) followed in parallel by pulsed amperometric detection (PAD) and online electrospray ionization mass spectrometry (ESI-MS). We validated our procedures using dispersin B, which is currently the only known PNAG-degrading enzyme.
- Published
- 2013
- Full Text
- View/download PDF
49. Thujone and thujone-containing herbal medicinal and botanical products: toxicological assessment.
- Author
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Pelkonen O, Abass K, and Wiesner J
- Subjects
- Animals, Bicyclic Monoterpenes, Dose-Response Relationship, Drug, GABA-A Receptor Antagonists administration & dosage, GABA-A Receptor Antagonists pharmacokinetics, Humans, Monoterpenes administration & dosage, Monoterpenes pharmacokinetics, Neurotoxicity Syndromes etiology, Pharmacogenetics, Plant Preparations chemistry, Rats, Risk Assessment, Species Specificity, Toxicity Tests, Acute, Toxicity Tests, Chronic, GABA-A Receptor Antagonists adverse effects, Monoterpenes adverse effects, Plant Preparations adverse effects
- Abstract
Thujone, a major component of the notoriously famous absinthe drink, is neurotoxic, although the current view rather downgrades its risk to humans. In animal studies, thujone inhibits the gamma-aminobutyric acid A (GABA(A)) receptor causing excitation and convulsions in a dose-dependent manner, although there are uncertainties about the doses required in humans. Toxicity of thujone has been extensively studied. Neurotoxicity is the principal toxic outcome in acute and chronic studies. There is some equivocal evidence of carcinogenicity in rats. Metabolism of thujone has been elucidated both in vitro and in vivo in several species and in vitro in human liver preparations. CYP2A6 is the principal metabolic enzyme, followed by CYP3A4 and, to a lesser extent, CYP2B6. CYP-associated metabolism may give rise to some potential pharmacogenetic and metabolic interaction consequences. Although the data base for determining exposure limits is of variable usefulness, the best estimates for allowable daily intakes via herbal preparations and diet are of the order of 3-7 mg/day. There are still important gaps in the knowledge required to assess thujone toxicity, the most important ones being human dose-concentration-effect relationships including the elucidation of bioavailability, and the actual toxicological consequences of potential pharmacogenetic variations and environmental factors., (Copyright © 2012 Elsevier Inc. All rights reserved.)
- Published
- 2013
- Full Text
- View/download PDF
50. Electromyographic assessment of muscle activity between genders during unilateral weight-bearing tasks using adjusted distances.
- Author
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Bouillon LE, Wilhelm J, Eisel P, Wiesner J, Rachow M, and Hatteberg L
- Abstract
Purpose/background: Researchers have observed differences in muscle activity patterns between males and females during functional exercises. The research methods employed have used various step heights and lunge distances to assess functional exercise making gender comparisons difficult. The purpose of this study was to examine core and lower extremity muscle activity between genders during single-limb exercises using adjusted distances and step heights based on a percentage of the participant's height., Methods: Twenty men and 20 women who were recreationally active and healthy participated in the study. Two-dimensional video and surface electromyography (SEMG) were used to assess performance during three exercise maneuvers (step down, forward lunge, and side-step lunge). Eight muscles were assessed using SEMG (rectus abdominus, external oblique, erector spinae, rectus femoris, tensor fascia latae, gluteus medius, gluteus maximus, biceps femoris). Maximal voluntary isometric contractions (MVIC) were used for each muscle and expressed as %MVIC to normalize SEMG to account for body mass differences. Exercises were randomized and distances were normalized to the participant's lower limb length. Descriptive statistics, mixed-model ANOVA, and ICCs with 95% confidence intervals were calculated., Results: Males were taller, heavier, and had longer leg length when compared to the females. No differences in %MVIC activity were found between genders by task across the eight muscles. For both males and females, the step down task resulted in higher %MVIC for gluteus maximus compared to lunge, (p=0.002). Step down exercise produced higher %MVIC for gluteus medius than lunge (p=0.002) and side step (p=0.006). ICC(3,3) ranged from moderate to high (0.74 to 0.97) for the three tasks., Conclusions: Muscle activation among the eight muscles was similar between females and males during the lunge, side-step, and step down tasks, with distances adjusted to leg length. Both males and females elicited higher muscle activity for gluteus maximus and gluteus medius as compared to the trunk, hip flexors, or hamstring muscles. However these values were well below the recruitment levels necessary for strengthening in both genders., Level of Evidence: 4.
- Published
- 2012
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