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11.
Marianna Małek Bożena Bogusz Paulina Mrowiec Mariusz Szuta Maciej Opach Iwona Skiba-Kurek Paweł Nowak Karolina Klesiewicz Alicja Budak Elżbieta Karczewska 《Revista iberoamericana de micología》2018,35(3):140-146
Background
Fungal rhinosinusitis has become an increasingly recognized disease, being Aspergillus species responsible for most of the cases. Its diagnosis is quite difficult because of the non-specific symptoms and low sensitivity of the current diagnostic methods.Aims
An Aspergillus-specific nested polymerase chain reaction (PCR) assay using biopsy specimens taken from the maxillary sinuses was performed in order to assess its usefulness. Conventional diagnostic methods (histology and culture) were also carried out.Methods
A case–control study was performed in the Institute of Stomatology, Jagiellonian University in Kraków, between 2011 and 2014. The case group consisted of 21 patients with suspected rhinosinusal mycetoma while the control group included 46 patients with no suspicion of fungal rhinosinusitis. The two-step PCR assay amplified an Aspergillus specific portion of the 18S rRNA gene. Interval estimation of sensitivity, specificity, positive (PPV) and negative (NPV) predictive values were calculated to assess the diagnostic test performance. The agreement between the PCR and the other tests was evaluated using the Kappa coefficient (k).Results
Ninety percent of the samples obtained from patients diagnosed with mycetoma yielded positive PCR results. The PCR showed almost perfect concordance with histology (k = 0.88). Sensitivity, specificity, PPV and NPV estimates were 90%; 95% CI: (55.5–99.7%), 98.3%; 95% CI: (90.9–100%), 90%; 95% CI: (55.5–99.7%) and 98.3%; 95% CI: (90.9–100%), respectively. One clinical sample showed growth of Aspergillus fumigatus and positive PCR despite the negative histological examination.Conclusions
Nested PCR assay is a promising diagnostic tool to evaluate the presence of Aspergillus in the tissue of maxillary sinus from patients with suspicion of sinus aspergillosis. 相似文献12.
Priscilla Y. L. Tng Leonela Z. Carabajal Paladino Michelle A. E. Anderson Zach N. Adelman Rennos Fragkoudis Rob Noad Luke Alphey 《PLoS neglected tropical diseases》2022,16(6)
Aedes aegypti and Ae. albopictus are the main vectors of mosquito-borne viruses of medical and veterinary significance. Many of these viruses have RNA genomes. Exogenously provided, e.g. transgene encoded, small RNAs could be used to inhibit virus replication, breaking the transmission cycle. We tested, in Ae. aegypti and Ae. albopictus cell lines, reporter-based strategies for assessing the ability of two types of small RNAs to inhibit a chikungunya virus (CHIKV) derived target. Both types of small RNAs use a Drosophila melanogaster pre-miRNA-1 based hairpin for their expression, either with perfect base-pairing in the stem region (shRNA-like) or containing two mismatches (miRNA-like). The pre-miRNA-1 stem loop structure was encoded within an intron; this allows co-expression of one or more proteins, e.g. a fluorescent protein marker tracking the temporal and spatial expression of the small RNAs in vivo. Three reporter-based systems were used to assess the relative silencing efficiency of ten shRNA-like siRNAs and corresponding miRNA-like designs. Two systems used a luciferase reporter RNA with CHIKV RNA inserted either in the coding sequence or within the 3’ UTR. A third reporter used a CHIKV derived split replication system. All three reporters demonstrated that while silencing could be achieved with both miRNA-like and shRNA-like designs, the latter were substantially more effective. Dcr-2 was required for the shRNA-like siRNAs as demonstrated by loss of inhibition of the reporters in Dcr-2 deficient cell lines. These positive results in cell culture are encouraging for the potential use of this pre-miRNA-1-based system in transgenic mosquitoes. 相似文献
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The unprecedented increase of the power conversion efficiency of metal‐halide perovskite solar cells has significantly outpaced the understanding of their fundamental properties. One of the biggest puzzles of perovskites has been the exciton binding energy, which has proved to be difficult to determine experimentally. Many contradictory reports can be found in the literature with values of the exciton binding energy from a few meV to a few tens of meV. In this review the results of the last few years of intense investigation of the exciton physic in perovskite materials are summarized. In particular a critical overview of the different experimental approaches used to determine exciton binding energy is provided. The problem of exciton binding energy in the context of the polar nature of perovskite crystals and related polaron effects which have been neglected to date in most of work is discussed. It is shown that polaron effects can reconcile at least some of the experimental observations and controversy present in the literature. Finally, the current status of the exciton fine structure in perovskite materials is summarized. The peculiar carrier–phonon coupling can help to understand the intriguing efficiency of light emission from metal‐halide perovskites. 相似文献
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Ariana M. Chao Thomas A. Wadden Robert I. Berkowitz George Blackburn Paula Bolin Jeanne M. Clark Mace Coday Jeffrey M. Curtis Linda M. Delahanty Gareth R. Dutton Mary Evans Linda J. Ewing John P. Foreyt Linda J. Gay Edward W. Gregg Helen P. Hazuda James O. Hill Edward S. Horton Denise K. Houston John M. Jakicic Robert W. Jeffery Karen C. Johnson Steven E. Kahn William C. Knowler Anne Kure Katherine L. Michalski Maria G. Montez Rebecca H. Neiberg Jennifer Patricio Anne Peters Xavier Pi‐Sunyer Henry Pownall David Reboussin Bruce Redmon W. Jack Rejeski Helmut Steinburg Martha Walker Donald A. Williamson Rena R. Wing Holly Wyatt Susan Z. Yanovski Ping Zhang 《Obesity (Silver Spring, Md.)》2020,28(5):893-901
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Dovgan Barbara Miklavčič Damijan Knežević Miomir Zupan Janja Barlič Ariana 《Cytotechnology》2021,73(3):391-411
Cytotechnology - Trehalose is a nontoxic disaccharide and a promising cryoprotection agent for medically applicable cells. In this study, the efficiency of combining trehalose with reversible... 相似文献
19.
Amy R. Sweeny Melanie Clerc Paulina A. Pontifes Saudamini Venkatesan Simon A. Babayan Amy B. Pedersen 《Proceedings. Biological sciences / The Royal Society》2021,288(1943)
Gastrointestinal (GI) helminths are common parasites of humans, wildlife, and livestock, causing chronic infections. In humans and wildlife, poor nutrition or limited resources can compromise an individual''s immune response, predisposing them to higher helminth burdens. This relationship has been tested in laboratory models by investigating infection outcomes following reductions of specific nutrients. However, much less is known about how diet supplementation can impact susceptibility to infection, acquisition of immunity, and drug efficacy in natural host–helminth systems. We experimentally supplemented the diet of wood mice (Apodemus sylvaticus) with high-quality nutrition and measured resistance to the common GI nematode Heligmosomoides polygyrus. To test whether diet can enhance immunity to reinfection, we also administered anthelmintic treatment in both natural and captive populations. Supplemented wood mice were more resistant to H. polygyrus infection, cleared worms more efficiently after treatment, avoided a post-treatment infection rebound, produced stronger general and parasite-specific antibody responses, and maintained better body condition. In addition, when applied in conjunction with anthelmintic treatment, supplemented nutrition significantly reduced H. polygyrus transmission potential. These results show the rapid and extensive benefits of a well-balanced diet and have important implications for both disease control and wildlife health under changing environmental conditions. 相似文献
20.
Bobby G. Ng Paulina Sosicka François Fenaille Annie Harroche Sandrine Vuillaumier-Barrot Mindy Porterfield Zhi-Jie Xia Shannon Wagner Michael J. Bamshad Marie-Christine Vergnes-Boiteux Sophie Cholet Stephen Dalton Anne Dell Thierry Dupré Mathieu Fiore Stuart M. Haslam Yohann Huguenin Tadahiro Kumagai Hudson H. Freeze 《American journal of human genetics》2021,108(6):1040-1052