13 results on '"Björn Berg"'
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2. Dynamics of trace and rare earth elements during long-term (over 4 years) decomposition in Scots pine and Norway spruce forest stands, Southern Sweden
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Mukesh K. Gautam, Björn Berg, Kwang-Sik Lee, Torbjörn Nilsson, and Hyung Seon Shin
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litter decomposition ,trace elements ,rare earth elements ,Scots pine ,Norway spruce ,coniferous forest ,Environmental sciences ,GE1-350 - Abstract
The temporal dynamics of 33 major, trace, and rare earth elements (REEs) were studied in the litter samples containing Swedish Norway spruce (Picea abies) (NSL) and Scots pine (Pinus sylvestris) (SPL), with the aim to assess their release and accumulation dynamics. Litter bags (8 × 8 cm) were incubated in paired monoculture stands with both the species for up to 5 years from 1979 to 1984 according to a randomized block design comprising 25 blocks (1 × 1 m) within an area of 625 m2. The decomposition rate was slightly higher for Scots pine litter (k = 0.315) than for Norway spruce litter (k = 0.217). During litter decomposition, at ∼70% accumulated mass loss (AML), the concentration of trace elements increased by >50% in both litter types compared to initial concentrations. The concentration change took place in a non-linear pattern, and polynomial quadratic regression between concentration change and accumulated mass loss resulted in significant relationships (adj R2 = 0.20–0.97; p = 0.15–0.95). A general upward convexity in the dynamics suggests that if further incubated in the field, decomposing litter could have accumulated more REEs in the organic matter. The results of this study can be useful for future studies in other ecosystems including metal-contaminated sites or element-depleted sites. Plant litter accumulation, its decomposition, and build-up of humic substances in the decomposing organic matter can act as a sink for elements and can be used as a management tool for ecological amelioration of metal-contaminated sites as well as natural systems that are impoverished, especially recuperating sites. The study’s findings have implications beyond such sites and can be useful in any research that seeks to understand the patterns of accumulation and release related to decomposition in different ecosystems.
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- 2023
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3. Effects of Climate and Atmospheric Nitrogen Deposition on Early to Mid-Term Stage Litter Decomposition Across Biomes
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TaeOh Kwon, Hideaki Shibata, Sebastian Kepfer-Rojas, Inger K. Schmidt, Klaus S. Larsen, Claus Beier, Björn Berg, Kris Verheyen, Jean-Francois Lamarque, Frank Hagedorn, Nico Eisenhauer, Ika Djukic, TeaComposition Network, Inger Kappel Schmidt, Klaus Steenberg Larsen, Jean Francois Lamarque, Adriano Caliman, Alain Paquette, Alba Gutiérrez-Girón, Alessandro Petraglia, Algirdas Augustaitis, Amélie Saillard, Ana Carolina Ruiz-Fernández, Ana I. Sousa, Ana I. Lillebø, Anderson da Rocha Gripp, Andrea Lamprecht, Andreas Bohner, André-Jean Francez, Andrey Malyshev, Andrijana Andrić, Angela Stanisci, Anita Zolles, Anna Avila, Anna-Maria Virkkala, Anne Probst, Annie Ouin, Anzar A. Khuroo, Arne Verstraeten, Artur Stefanski, Aurora Gaxiola, Bart Muys, Beatriz Gozalo, Bernd Ahrends, Bo Yang, Brigitta Erschbamer, Carmen Eugenia Rodríguez Ortíz, Casper T. Christiansen, Céline Meredieu, Cendrine Mony, Charles Nock, Chiao-Ping Wang, Christel Baum, Christian Rixen, Christine Delire, Christophe Piscart, Christopher Andrews, Corinna Rebmann, Cristina Branquinho, Dick Jan, Dirk Wundram, Dušanka Vujanović, E. Carol Adair, Eduardo Ordóñez-Regil, Edward R. Crawford, Elena F. Tropina, Elisabeth Hornung, Elli Groner, Eric Lucot, Esperança Gacia, Esther Lévesque, Evanilde Benedito, Evgeny A. Davydov, Fábio Padilha Bolzan, Fernando T. Maestre, Florence Maunoury-Danger, Florian Kitz, Florian Hofhansl, Flurin Sutter, Francisco de Almeida Lobo, Franco Leadro Souza, Franz Zehetner, Fulgence Kouamé Koffi, Georg Wohlfahrt, Giacomo Certini, Gisele Daiane Pinha, Grizelle González, Guylaine Canut, Harald Pauli, Héctor A. Bahamonde, Heike Feldhaar, Heinke Jäger, Helena Cristina Serrano, Hélène Verheyden, Helge Bruelheide, Henning Meesenburg, Hermann Jungkunst, Hervé Jactel, Hiroko Kurokawa, Ian Yesilonis, Inara Melece, Inge van Halder, Inmaculada García Quirós, István Fekete, Ivika Ostonen, Jana Borovská, Javier Roales, Jawad Hasan Shoqeir, Jean-Christophe Lata, Jean-Luc Probst, Jeyanny Vijayanathan, Jiri Dolezal, Joan-Albert Sanchez-Cabeza, Joël Merlet, John Loehr, Jonathan von Oppen, Jörg Löffler, José Luis Benito Alonso, José-Gilberto Cardoso-Mohedano, Josep Peñuelas, Joseph C. Morina, Juan Darío Quinde, Juan J. Jiménez, Juha M. Alatalo, Julia Seeber, Julia Kemppinen, Jutta Stadler, Kaie Kriiska, Karel Van den Meersche, Karibu Fukuzawa, Katalin Szlavecz, Katalin Juhos, Katarína Gerhátová, Kate Lajtha, Katie Jennings, Katja Tielbörger, Kazuhiko Hoshizaki, Ken Green, Klaus Steinbauer, Laryssa Pazianoto, Laura Dienstbach, Laura Yahdjian, Laura J. Williams, Laurel Brigham, Lee Hanna, Liesbeth van den Brink, Lindsey Rustad, Lourdes Morillas, Luciana Silva Carneiro, Luciano Di Martino, Luis Villar, Luísa Alícida Fernandes Tavares, Madison Morley, Manuela Winkler, Marc Lebouvier, Marcello Tomaselli, Marcus Schaub, Maria Glushkova, Maria Guadalupe Almazan Torres, Marie-Anne de Graaff, Marie-Noëlle Pons, Marijn Bauters, Marina Mazón, Mark Frenzel, Markus Wagner, Markus Didion, Maroof Hamid, Marta Lopes, Martha Apple, Martin Weih, Matej Mojses, Matteo Gualmini, Matthew Vadeboncoeur, Michael Bierbaumer, Michael Danger, Michael Scherer-Lorenzen, Michal Růžek, Michel Isabellon, Michele Di Musciano, Michele Carbognani, Miglena Zhiyanski, Mihai Puşcaş, Milan Barna, Mioko Ataka, Miska Luoto, Mohammed H. Alsafaran, Nadia Barsoum, Naoko Tokuchi, Nathalie Korboulewsky, Nicolas Lecomte, Nina Filippova, Norbert Hölzel, Olga Ferlian, Oscar Romero, Osvaldo Pinto-Jr, Pablo Peri, Pavel Dan Turtureanu, Peter Haase, Peter Macreadie, Peter B. Reich, Petr Petřík, Philippe Choler, Pierre Marmonier, Quentin Ponette, Rafael Dettogni Guariento, Rafaella Canessa, Ralf Kiese, Rebecca Hewitt, Robert Weigel, Róbert Kanka, Roberto Cazzolla Gatti, Rodrigo Lemes Martins, Romà Ogaya, Romain Georges, Rosario G. Gavilán, Sally Wittlinger, Sara Puijalon, Satoshi Suzuki, Schädler Martin, Schmidt Anja, Sébastien Gogo, Silvio Schueler, Simon Drollinger, Simone Mereu, Sonja Wipf, Stacey Trevathan-Tackett, Stefan Stoll, Stefan Löfgren, Stefan Trogisch, Steffen Seitz, Stephan Glatzel, Susanna Venn, Sylvie Dousset, Taiki Mori, Takanori Sato, Takuo Hishi, Tatsuro Nakaji, Theurillat Jean-Paul, Thierry Camboulive, Thomas Spiegelberger, Thomas Scholten, Thomas J. Mozdzer, Till Kleinebecker, Tomáš Rusňák, Tshililo Ramaswiela, Tsutom Hiura, Tsutomu Enoki, Tudor-Mihai Ursu, Umberto Morra di Cella, Ute Hamer, Valentin Klaus, Valter Di Cecco, Vanessa Rego, Veronika Fontana, Veronika Piscová, Vincent Bretagnolle, Vincent Maire, Vinicius Farjalla, Vittoz Pascal, Wenjun Zhou, Wentao Luo, William Parker, Yasuhiro Utsumi, Yuji Kominami, Zsolt Kotroczó, and Zsolt Tóth
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tea bag ,Green tea ,Rooibos tea ,litter decomposition ,carbon turnover ,nitrogen deposition ,Forestry ,SD1-669.5 ,Environmental sciences ,GE1-350 - Abstract
Litter decomposition is a key process for carbon and nutrient cycling in terrestrial ecosystems and is mainly controlled by environmental conditions, substrate quantity and quality as well as microbial community abundance and composition. In particular, the effects of climate and atmospheric nitrogen (N) deposition on litter decomposition and its temporal dynamics are of significant importance, since their effects might change over the course of the decomposition process. Within the TeaComposition initiative, we incubated Green and Rooibos teas at 524 sites across nine biomes. We assessed how macroclimate and atmospheric inorganic N deposition under current and predicted scenarios (RCP 2.6, RCP 8.5) might affect litter mass loss measured after 3 and 12 months. Our study shows that the early to mid-term mass loss at the global scale was affected predominantly by litter quality (explaining 73% and 62% of the total variance after 3 and 12 months, respectively) followed by climate and N deposition. The effects of climate were not litter-specific and became increasingly significant as decomposition progressed, with MAP explaining 2% and MAT 4% of the variation after 12 months of incubation. The effect of N deposition was litter-specific, and significant only for 12-month decomposition of Rooibos tea at the global scale. However, in the temperate biome where atmospheric N deposition rates are relatively high, the 12-month mass loss of Green and Rooibos teas decreased significantly with increasing N deposition, explaining 9.5% and 1.1% of the variance, respectively. The expected changes in macroclimate and N deposition at the global scale by the end of this century are estimated to increase the 12-month mass loss of easily decomposable litter by 1.1–3.5% and of the more stable substrates by 3.8–10.6%, relative to current mass loss. In contrast, expected changes in atmospheric N deposition will decrease the mid-term mass loss of high-quality litter by 1.4–2.2% and that of low-quality litter by 0.9–1.5% in the temperate biome. Our results suggest that projected increases in N deposition may have the capacity to dampen the climate-driven increases in litter decomposition depending on the biome and decomposition stage of substrate.
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- 2021
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4. Anatomy-guided resections for paralimbic tumors in the temporo-insular region: combining tumor and epilepsy surgery concepts
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Emad Alkassm, Alexander Grote, Björn Berger, Friedrich G. Woermann, Tunc Faik Ersoy, Roland Coras, Thilo Kalbhenn, and Matthias Simon
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paralimbic ,temporo-mesial ,insula ,supramarginal resection ,epilepsy surgery ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
ObjectTumors in the temporo-mesial region often extend into the insula and vice versa. The present study investigated the results of a surgical strategy that combines principles of tumor and epilepsy surgery.MethodsWe retrospectively analyzed 157 consecutive patients with intrinsic brain tumors in the temporo-mesial region, with varying degrees of extensions into the insula (44 patients, 28.0%). The surgical strategy utilized “anatomy-guided resection,” targeting specific anatomical compartments infiltrated by the tumor (e.g., temporal pole, anterior temporo-mesial region = uncus and hippocampal head, posterior temporo-mesial, insula) rather than treating the tumor as a single mass.ResultsThe most frequent histologies were ganglioglioma CNS WHO grade 1 (55 patients, 35.0%) and IDH1 wildtype glioblastoma (36 patients, 22.9%). Tumor infiltration was most commonly found in the anterior temporo-mesial compartment (145 patients, 92.4%). An anterior temporal lobectomy was part of the surgical strategy in 131 cases (83.4%). Seventy-six patients (48.4%) with drug-resistant epilepsy underwent a formal presurgical epilepsy work-up, including depth electrode placement in three cases. Complete resections were achieved in 117 patients (74.5%), with supramarginal resections performed in 89 cases (56.7%). Four patients experienced non-temporary neurological complications (CTCAE grade 3–5). At 6 months, 127 of 147 assessable patients (86.4%) were free from seizures or auras (ILAE class 1), excluding early postoperative seizures (
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- 2024
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5. Cofactors of drug hypersensitivity—A monocenter retrospective analysis
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Johanna Kühl, Björn Bergh, Matthias Laudes, Silke Szymczak, and Guido Heine
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drug allergy ,drug hypersensitivity reaction ,antibiotic ,beta-lactam ,nonopioid analgesic ,cofactor ,Immunologic diseases. Allergy ,RC581-607 - Abstract
BackgroundDrug hypersensitivity reactions (DHRs) are major medical problems that influence the treatment of patients by both under- and overdiagnosis. Still, little is known about the role of predisposing or protecting cofactors of DHR.ObjectiveThis study aims to determine drug-specific cofactors in patients with DHR.MethodsRetrospective file chart analysis of inpatients with suspected DHR in our department between 2015 and 2020 was performed. Descriptive statistics and multiple logistic regression were conducted for the estimation and statistical interference.ResultsDHRs were suspected in 393 patients with 678 culprit drugs. In 183 cases, drug hypersensitivities were confirmed, mostly against nonopioid analgesic drugs and antibiotics. Multiple logistic regression analysis identified a positive association of antibiotic hypersensitivity with obesity [odds ratio (OR) 5.75, average marginal effect (AME) +24.4%] and age and a negative association with arterial hypertension, female sex, elevated immunoglobulin E (IgE), and allergic rhinitis. Hypersensitivity to nonopioid analgesics was associated with atopic dermatitis (OR 10.28, AME +28.5%), elevated IgE, and arterial hypertension.ConclusionsDrug-specific cofactors of DHR include obesity for antibiotics and atopic dermatitis for nonopioid analgesics, the knowledge of which may improve the risk calculation for drug provocation tests.
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- 2023
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6. Endoscopic removal of a massive trichobezoar in a pediatric patient by using a variceal ligator cap: A case report and literature review
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Dan Lu, Björn Berglund, Yi Xia, Ajay Jain, Qing Gu, and Feng Ji
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endoscopy ,removal ,trichobezoar ,pediatric ,case report ,Medicine (General) ,R5-920 - Abstract
A trichobezoar is commonly formed in the gastrointestinal tract by ingestion of an individual’s own hair. A trichobezoar formed by hair and artificial materials constitutes a rare etiology scarcely reported in the current literature. A mixture with hair-like synthetic fibers not only increases the risk for trichobezoar formation but also makes it more difficult for endoscopic removal. Herein, we report on a case in which a trichobezoar, caused by the consumption of human hair and synthetic yarn, was successfully removed endoscopically with a variceal ligator cap without further complications for the patient. This case report aims to raise awareness among endoscopists that using a variceal ligator cap may be a suitable option in the management of large trichobezoars containing synthetic fibers.
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- 2022
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7. Dissemination of blaNDM-5 and mcr-8.1 in carbapenem-resistant Klebsiella pneumoniae and Klebsiella quasipneumoniae in an animal breeding area in Eastern China
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Chengxia Yang, Jingyi Han, Björn Berglund, Huiyun Zou, Congcong Gu, Ling Zhao, Chen Meng, Hui Zhang, Xianjun Ma, and Xuewen Li
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carbapenem-resistant Klebsiella spp. ,animal breeding area ,blaNDM-5 ,mcr-8.1 ,plasmid ,clonal expansion ,Microbiology ,QR1-502 - Abstract
Animal farms have become one of the most important reservoirs of carbapenem-resistant Klebsiella spp. (CRK) owing to the wide usage of veterinary antibiotics. “One Health”-studies observing animals, the environment, and humans are necessary to understand the dissemination of CRK in animal breeding areas. Based on the concept of “One-Health,” 263 samples of animal feces, wastewater, well water, and human feces from 60 livestock and poultry farms in Shandong province, China were screened for CRK. Five carbapenem-resistant Klebsiella pneumoniae (CRKP) and three carbapenem-resistant Klebsiella quasipneumoniae (CRKQ) strains were isolated from animal feces, human feces, and well water. The eight strains were characterized by antimicrobial susceptibility testing, plasmid conjugation assays, whole-genome sequencing, and bioinformatics analysis. All strains carried the carbapenemase-encoding gene blaNDM-5, which was flanked by the same core genetic structure (IS5-blaNDM-5-bleMBL-trpF-dsbD-IS26-ISKox3) and was located on highly related conjugative IncX3 plasmids. The colistin resistance gene mcr-8.1 was carried by three CRKP and located on self-transmissible IncFII(K)/IncFIA(HI1) and IncFII(pKP91)/IncFIA(HI1) plasmids. The genetic context of mcr-8.1 consisted of IS903-orf-mcr-8.1-copR-baeS-dgkA-orf-IS903 in three strains. Single nucleotide polymorphism (SNP) analysis confirmed the clonal spread of CRKP carrying-blaNDM-5 and mcr-8.1 between two human workers in the same chicken farm. Additionally, the SNP analysis showed clonal expansion of CRKP and CRKQ strains from well water in different farms, and the clonal CRKP was clonally related to isolates from animal farms and a wastewater treatment plant collected in other studies in the same province. These findings suggest that CRKP and CRKQ are capable of disseminating via horizontal gene transfer and clonal expansion and may pose a significant threat to public health unless preventative measures are taken.
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- 2022
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8. Comprehensive Evaluation of Anti-PD-1, Anti-PD-L1, Anti-CTLA-4 and Their Combined Immunotherapy in Clinical Trials: A Systematic Review and Meta-analysis
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Ze Xiang, Jiayuan Li, Zhengyu Zhang, Chao Cen, Wei Chen, Bin Jiang, Yiling Meng, Ying Wang, Björn Berglund, Guanghua Zhai, and Jian Wu
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immune checkpoint inhibitor ,cancer immunotherapy ,programmed death-1 (PD-1) ,programmed death-ligand-1 (PD-L1) ,cytotoxic T lymphocyte antigen-4 (CTLA-4) ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Immunotherapy with immune checkpoint inhibitor (ICI) drugs is gradually becoming a hot topic in cancer treatment. To comprehensively evaluate the safety and efficacy of ICI drugs, we employed the Bayesian model and conducted a network meta-analysis in terms of progression-free survival (PFS), overall survival (OS) and severe adverse events (AEs). Our study found that treatment with ipilimumab was significantly worse than standard therapies in terms of PFS, whereas treatment with cemiplimab significantly improved PFS. The results also indicated that cemiplimab was the best choice for PFS. Treatment with nivolumab, pembrolizumab and nivolumab plus ipilimumab significantly improved OS compared to standard therapies. In terms of OS, cemiplimab was found to be the best choice, whereas avelumab was the worst. In terms of severe AEs, atezolizumab, avelumab, durvalumab, nivolumab, and pembrolizumab all significantly reduced the risk of grade 3 or higher AEs compared to standard therapy. The least likely to be associated with severe AEs were as follows: cemiplimab, avelumab, nivolumab, atezolizumab, and camrelizumab, with nivolumab plus ipilimumab to be the worst. Therefore, different ICI drug therapies may pose different risks in terms of PFS, OS and severe AEs. Our study may provide new insights and strategies for the clinical practice of ICI drugs.
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- 2022
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9. Extraction of Fish Bones Embedded in the Esophagus via Endoscopic Submucosal Dissection: Two Case Reports and Literature Review
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Dan Lu, Lu Lv, Qing Gu, Ajay Jain, Björn Berglund, and Feng Ji
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foreign body ,esophagus ,migration ,endoscopic submucosal dissection ,case report ,Medicine (General) ,R5-920 - Abstract
Foreign body ingestion is a common problem encountered at gastroenterology clinics and emergency rooms which can cause serious complications. Usually, foreign bodies are directly visible with flexible endoscopes and can be readily removed. However, when foreign bodies migrate into the deeper tissue of the esophagus, surgery is typically required. There is currently no consensus regarding the best treatment. In this report, we present two cases in which fish bones embedded in the submucosal and muscularis propria of the esophagus were successfully removed via endoscopic submucosal dissection (ESD). Both patients were discharged without any complications.
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- 2021
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10. Probiotic Gastrointestinal Transit and Colonization After Oral Administration: A Long Journey
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Shengyi Han, Yanmeng Lu, Jiaojiao Xie, Yiqiu Fei, Guiwen Zheng, Ziyuan Wang, Jie Liu, Longxian Lv, Zongxin Ling, Björn Berglund, Mingfei Yao, and Lanjuan Li
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probiotics ,colonization ,adhesion ,colonization resistance ,gut microbiota ,Microbiology ,QR1-502 - Abstract
Orally administered probiotics encounter various challenges on their journey through the mouth, stomach, intestine and colon. The health benefits of probiotics are diminished mainly due to the substantial reduction of viable probiotic bacteria under the harsh conditions in the gastrointestinal tract and the colonization resistance caused by commensal bacteria. In this review, we illustrate the factors affecting probiotic viability and their mucoadhesive properties through their journey in the gastrointestinal tract, including a discussion on various mucosadhesion-related proteins on the probiotic cell surface which facilitate colonization.
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- 2021
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11. Serotype Is Associated With High Rate of Colistin Resistance Among Clinical Isolates of Salmonella
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Qixia Luo, Yuan Wang, Hao Fu, Xiao Yu, Beiwen Zheng, Yunbo Chen, Björn Berglund, and Yonghong Xiao
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Salmonella enterica ,serotype ,colistin susceptibility ,clinical isolates ,phylogenetic analysis ,pmr genes ,Microbiology ,QR1-502 - Abstract
To investigate the prevalence, probable mechanisms and serotype correlation of colistin resistance in clinical isolates of Salmonella from patients in China, Salmonella isolates were collected from fecal and blood samples of patients. In this study, 42.8% (136/318) clinical isolated Salmonella were resistant to colistin. MIC distribution for colistin at serotype level among the two most prevalent serotypes originating from humans in China indicated that Salmonella Enteritidis (83.9% resistance, 125/149) were significantly less susceptible than Salmonella Typhimurium (15.3% resistance, 9/59, P < 0.01). mcr genes and mutations in PmrAB confer little for rate of colistin resistant Salmonella isolated from human patients. Phylogenetic tree based on core-genome single nucleotide polymorphisms (SNPs) was separately by the serotypes and implied a diffused distribution of MICs in the same serotype isolates. Relatvie expression levels of colistin resistant related pmr genes were significantly higher in non-mcr colistin resistant S. Typhimurium than in colistin sensitive S. Typhimurium, but no discernable differences between colistin resistant and sensitive S. Enteritidis, indicating a different mechanism between colistin resistant S. Typhimurium and S. Enteritidis. In conclusion, colistin susceptibility and colistin resistant mechanism of clinical isolated Salmonella were closely associated with specific serotypes, at least in the two most prevalent serotype Enteritidis and Typhimurium. We suggest clinical microbiology laboratory interpreting Salmonella colistin MIC results in the serotype level.
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- 2020
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12. Hypervirulence Markers Among Non-ST11 Strains of Carbapenem- and Multidrug-Resistant Klebsiella pneumoniae Isolated From Patients With Bloodstream Infections
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Ping Shen, Björn Berglund, Yong Chen, Yanzi Zhou, Tingting Xiao, Yonghong Xiao, and Kai Zhou
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bloodstream infection ,multidrug resistance ,carbapenem resistance ,Klebsiella pneumoniae ,hypervirulence ,Microbiology ,QR1-502 - Abstract
Multidrug-resistant Klebsiella pneumoniae and hypervirulent K. pneumoniae (hvKP) have traditionally been considered two individual populations; however, strains displaying both phenotypes have emerged during the recent decade. Understanding the genotypic and phenotypic basis of the convergence could be of clinical importance. In this study, we aimed to evaluate the pathogenicity associated with different combinations of genotypes (i.e., sequence types, virulence factors, and capsular serotypes) and phenotypes (i.e., hypermucoviscosity and drug susceptibility) in K. pneumoniae. A total of 11 K. pneumoniae isolates causing bloodstream infections were included in the study, and they were assigned to seven STs (ST23, ST15, ST268, ST660, ST86, ST65, and ST1660) and carried various K-loci (KL1, KL2, KL16, KL20, and KL24). Hypermucoviscosity was observed for six isolates. blaKPC–2 was detected in six carbapenem-resistant isolates, and the remaining ones were either multidrug-resistant or resistant to two types of antibiotics. Aerobactin- and yersiniabactin-encoding genes were detected in all isolates. Although rmpA2 was detected in all isolates, most contained frameshift mutations (82%). Genes encoding salmochelin, RmpA, and PEG344 were detected in seven isolates. Colibactin-encoding genes were carried by six isolates. Discrepancies among measured virulence in Galleria mellonella and the serum-killing assay, and genotypes and phenotypes were detected. The results illustrate the complexity and difficulty with the current knowledge of hypervirulence to predict the phenotype by using genetic and phenotypic markers. Additionally, the emergence of carbapenem resistance in two isolates of KPC-2-producing hvKP of different sequence types emphasizes the urgency with which reliable clinical diagnostics for hvKP is needed.
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- 2020
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13. Characterization of Clinically Relevant Strains of Extended-Spectrum β-Lactamase-Producing Klebsiella pneumoniae Occurring in Environmental Sources in a Rural Area of China by Using Whole-Genome Sequencing
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Xiaohui Chi, Björn Berglund, Huiyun Zou, Beiwen Zheng, Stefan Börjesson, Xiang Ji, Jakob Ottoson, Cecilia Stålsby Lundborg, Xuewen Li, and Lennart E. Nilsson
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Klebsiella pneumoniae ,extended-spectrum β-lactamase ,environment ,feces ,water ,multilocus sequence typing ,Microbiology ,QR1-502 - Abstract
Klebsiella pneumoniae is a gram-negative, opportunistic pathogen, and a common cause of healthcare-associated infections such as pneumonia, septicemia, and urinary tract infection. The purpose of this study was to survey the occurrence of and characterize K. pneumoniae in different environmental sources in a rural area of Shandong province, China. Two hundred and thirty-one samples from different environmental sources in 12 villages were screened for extended-spectrum β-lactamase-(ESBL)-producing K. pneumoniae, and 14 (6%) samples were positive. All isolates were multidrug-resistant and a few of them belonged to clinically relevant strains which are known to cause hospital outbreaks worldwide. Serotypes, virulence genes, serum survival, and phagocytosis survival were analyzed and the results showed the presence of virulence factors associated with highly virulent clones and a high degree of phagocytosis survivability, indicating the potential virulence of these isolates. These results emphasize the need for further studies designed to elucidate the role of the environment in transmission and dissemination of ESBL-producing K. pneumoniae and the potential risk posed to human and environmental health.
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- 2019
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