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491.
Shima Zamanian Samira Mohammadi-Yeganeh Vahid Kia 《Preparative biochemistry & biotechnology》2017,47(9):847-851
During the purification of human recombinant erythropoietin (rEPO) from host cells, residual DNA may remain in final products. This contamination is a risk factor for patients and may result in the inactivation of some tumor suppressor genes or activation of oncogenes if its concentration is more than the standard defined by WHO. Based on WHO’s criteria, acceptable level of residual DNA in biopharmaceuticals is less than 10–100?pg/dose. In this study, we have designed a sensitive and specific quantitative real-time polymerase chain reaction (PCR) assay for the detection of residual DNA in human rEPO products. All reported sequences of CHO’s GAPDH gene were retrieved from GenBank, and a multiple alignment was performed using Mega 6 software to find conserved regions of the gene. Primers and probe were designed by AlleleID7 software for the highly conserved region. Quantitative real-time PCR showed an R2 value more than 0.99 and the efficiency equal to 101% indicating a highly accurate and efficiency of the reaction, respectively. Based on the standard curve, the limit of detection of the assay was determined to be 10?copies/µL (0.00967?fg/µL). In addition, the inter- and intra-assay of the test were determined to be 1.14% and 0.65%, respectively, which are in acceptable range according to the WHO’s guidelines. 相似文献
492.
493.
Laís Samira Correia Nunes Cristiane Akemi Umetsu Antonio Fernando Monteiro Camargo 《Freshwater Biology》2020,65(11):1894-1905
- The coastal rivers of the São Paulo State in SE Brazil have different lengths and seawater influence. We evaluated whether: (1) environmental heterogeneity (EH) is associated with the species and life-form richness of aquatic macrophytes; and (2) EH and geographical distance influence species composition in these coastal rivers.
- We recorded the macrophyte species and life form occurrence and collected explanatory variables characterising the water, sediment, and river channel at 100 sampling sites over 8 rivers. We applied a principal component analysis to the explanatory variables and calculated the rivers' EH using the range of principal component 1 scores. We also determined the position of each river mouth along the coastline to measure the distance between the rivers. We used quasi-Poisson generalised linear models to evaluate the effects of EH on richness of species and life forms. To determine the effect of EH and geographical distance (Euclidean distance matrices) on the variation in species composition (Jaccard dissimilarity matrix) among the rivers, we applied multiple regressions on distance matrices.
- The most heterogeneous river had heterogeneity score about five times greater than the least heterogeneous river. Sediment salinity, river width, total phosphorus concentration of water and distance from river mouth were the most important variables contributing to the rivers' EH. We found that EH did not explain variation in species richness; however, it had a significant positive relationship with life-form richness. The effect of EH was greater than that of the geographical distance on the variation in species composition among the rivers. The pairs of rivers with the most similar EH were the most similar in species composition, but not all of them were geographically close.
- We conclude that EH influences life-form richness but does not influence species richness of aquatic macrophytes in the coastal rivers we studied; however, EH does influence species composition regardless of geographical distance among rivers.
494.
Laila Ben Said Jean-Guillaume Emond-Rheault Samira Soltani Sofiane Telhig Séverine Zirah Sylvie Rebuffat Moussa Sory Diarra Lawrence Goodridge Roger C. Levesque Ismail Fliss 《Environmental microbiology》2020,22(7):2907-2920
In livestock production, antibiotics are used to promote animal growth, control infections and thereby increase profitability. This practice has led to the emergence of multiresistant bacteria such as Salmonella, of which some serovars are disseminated in the environment. The objective of this study is to evaluate microcin J25 as an inhibitor of Salmonella enterica serovars of various origins including human, livestock and food. Among the 116 isolates tested, 37 (31.8%) were found resistant to at least one antibiotic, and 28 were multiresistant with 19 expressing the penta-resistant phenotype ACSSuT. Microcin J25 inhibited all isolates, with minimal inhibitory concentration values ranging from 0.06 μg/ml (28.4 nM) to 400 μg/ml (189 μM). Interestingly, no cross-resistance was found between microcin J25 and antibiotics. Multiple sequence alignments of genes encoding for the different proteins involved in the recognition and transport of microcin J25 showed that only ferric-hydroxamate uptake is an essential determinant for susceptibility of S. enterica to microcin J25. Examination of Salmonella strains exposed to microcin J25 by transmission electronic microscopy showed for the first-time involvement of a pore formation mechanism. Microcin J25 was a strong inhibitor of several multiresistant isolates of Salmonella and may have a great potential as an alternative to antibiotics. 相似文献
495.
Molaei Ramsheh Samira Erfanian Omidvar Maryam Tabasinezhad Maryam Alipoor Behnam Salmani Tayyeb Ali Ghaedi Hamid 《Molecular biology reports》2020,47(12):9699-9714
Molecular Biology Reports - The mitochondrial encephalomyopathies represent a clinically heterogeneous group of neurodegenerative disorders. The clinical phenotype of patients could be explained by... 相似文献
496.
Amir Biranvand Oldřich Nedvĕd Samira Karimi Hassanali Vahedi Shahram Hesami Hossein Lotfalizadeh 《法国昆虫学会纪事》2020,56(2):106-114
Summary Over the past few decades, many records of the parasitoids parasitizing Coccinellidae have been reported from Iran. Some of them, presented in hard to access conference proceedings, theses, older books and journal articles, were then inaccurately quoted in other papers. Furthermore, some other records were subsequently considered misidentifications and the corrected identity of the parasitoids was proposed in later published papers. Due to the accumulation of that misleading information, we decided to gather and critically evaluate all available Iranian data on the parasitoids of Coccinellidae. To the review presented here we also added new data on the parasitism of Coccinella septempunctata L. by a braconid Dinocampus coccinellae (Schrank) in the Lorestan province and on the parasitism of Hyperaspis pseudopustulata Mulsant by an encyrtid Homalotylus flaminius (Dalman) in the Kermanshah province. Hyperaspis pseudopustulata is a new host for H. flaminius, and is also a species new to the fauna of Iran. Altogether, our review revealed one species of dipteran and 16 species of hymenopteran parasitoids associated with Coccinellidae in Iran. The identity of some of those species, however, seems uncertain and should be re-examined. 相似文献
497.
Riadh Hammami Abdelmajid Zouhir Karim Naghmouchi Jeannette Ben Hamida Ismail Fliss 《BMC bioinformatics》2008,9(1):121
Background
The exponential growth of research in molecular biology has brought concomitant proliferation of databases for stocking its findings. A variety of protein sequence databases exist. While all of these strive for completeness, the range of user interests is often beyond their scope. Large databases covering a broad range of domains tend to offer less detailed information than smaller, more specialized resources, often creating a need to combine data from many sources in order to obtain a complete picture. Scientific researchers are continually developing new specific databases to enhance their understanding of biological processes. 相似文献498.
Azrag Abdelmutalab G. A. Ndlela Shepard Mkiga Abdullah M. Mohamed Samira Abuelgasim 《Journal of Insect Behavior》2021,34(5-6):319-333
Journal of Insect Behavior - Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is a polyphagous insect pest native to sub-Saharan Africa. The larvae burrow into the fruit and... 相似文献
499.
Marianne Lucas-Hourani Daniel Dauzonne Pierre Jorda Ga?lle Cousin Alexandru Lupan Olivier Helynck Grégory Caignard Geneviève Janvier Gwéna?lle André-Leroux Samira Khiar Nicolas Escriou Philippe Desprès Yves Jacob Hélène Munier-Lehmann Frédéric Tangy Pierre-Olivier Vidalain 《PLoS pathogens》2013,9(10)
500.
Bruno H. Saranholi Karen G. Rodriguez-Castro Carolina S. Carvalho Samira Chahad-Ehlers Carla C. Gestich Sónia C. S. Andrade Patrícia D. Freitas Pedro M. Galetti Jr 《Molecular ecology resources》2023,23(8):1790-1799
Ingested-derived DNA (iDNA) from insects represents a powerful tool for assessing vertebrate diversity because insects are easy to sample, have a diverse diet and are widely distributed. Because of these advantages, the use of iDNA for detecting mammals has gained increasing attention. Here we aimed to compare the effectiveness of mosquitoes and flies to detect mammals with a small sampling effort in a semi-controlled area, a zoo that houses native and non-native species. We compared mosquitoes and flies regarding the number of mammal species detected, the amount of mammal sequence reads recovered, and the flight distance range for detecting mammals. We also verified if the combination of two mini-barcodes (12SrRNA and 16SrRNA) would perform better than either mini-barcode alone to inform local mammal biodiversity from iDNA. To capture mosquitoes and flies, we distributed insect traps in eight sampling points during 5 days. We identified 43 Operational Taxonomic Units from 10 orders, from the iDNA of 17 mosquitoes and 46 flies. There was no difference in the number of species recovered per individual insect between mosquitoes and flies, but the number of flies captured was higher, resulting in more mammal species recovered by flies. Eight species were recorded exclusively by mosquitoes and 20 by flies, suggesting that using both samplers would allow a more comprehensive screening of the biodiversity. The maximum distance recorded was 337 m for flies and 289 m for mosquitoes, but the average range distance did not differ between insect groups. Our assay proved to be efficient for mammal detection, considering the high number of species detected with a reduced sampling effort. 相似文献