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941.
Jaime A. Teixeira da Silva 《In vitro cellular & developmental biology. Plant》2013,49(6):690-698
Cryopreservation can be a stable, long-term method of germplasm conservation, but successful application can be challenging for tropical material. To optimize survival and re-growth from cryopreserved tissues derived from protocorm-like bodies (PLBs) of hybrid Cymbidium Twilight Moon ‘Day Light’, the effects of explant type (intact PLBs, half-PLBs, or PLB longitudinal thin cell layers) and various explant treatments were studied. Encapsulation in alginate beads was essential, and intact PLBs were best for cryopreservation, based on survival and ability to form neo-PLBs and/or percentage re-growth. Osmotic hydration of intact PLBs in 2% sucrose for 24 h increased neo-PLB formation and re-growth, with the best responses seen when PLBs were excised from alginate beads prior to re-growth after cryopreservation. Both non-transgenic and transgenic PLBs were amenable to cryopreservation for up to 1 year using these methods. This optimized protocol will improve the viability of hybrid Cymbidium germplasm after long-term cryopreservation. 相似文献
942.
Elinor K Karlsson Snaevar Sigurdsson Emma Ivansson Rachael Thomas Ingegerd Elvers Jason Wright Cedric Howald Noriko Tonomura Michele Perloski Ross Swofford Tara Biagi Sarah Fryc Nathan Anderson Celine Courtay-Cahen Lisa Youell Sally L Ricketts Sarah Mandlebaum Patricio Rivera Henrik von Euler William C Kisseberth Cheryl A London Eric S Lander Guillermo Couto Kenine Comstock Mike P Starkey Jaime F Modiano Matthew Breen Kerstin Lindblad-Toh 《Genome biology》2013,14(12):1-16
Background
Canine osteosarcoma is clinically nearly identical to the human disease, but is common and highly heritable, making genetic dissection feasible.Results
Through genome-wide association analyses in three breeds (greyhounds, Rottweilers, and Irish wolfhounds), we identify 33 inherited risk loci explaining 55% to 85% of phenotype variance in each breed. The greyhound locus exhibiting the strongest association, located 150 kilobases upstream of the genes CDKN2A/B, is also the most rearranged locus in canine osteosarcoma tumors. The top germline candidate variant is found at a >90% frequency in Rottweilers and Irish wolfhounds, and alters an evolutionarily constrained element that we show has strong enhancer activity in human osteosarcoma cells. In all three breeds, osteosarcoma-associated loci and regions of reduced heterozygosity are enriched for genes in pathways connected to bone differentiation and growth. Several pathways, including one of genes regulated by miR124, are also enriched for somatic copy-number changes in tumors.Conclusions
Mapping a complex cancer in multiple dog breeds reveals a polygenic spectrum of germline risk factors pointing to specific pathways as drivers of disease. 相似文献943.
944.
Environmental Biology of Fishes - Orestias ascotanensis Parenti is a critically endangered endemic species of the Chilean high Andean systems, found only in the springs of the Ascotán saltpan.... 相似文献
945.
Maria M. C. da Silva Jos B. de Araújo-Neto Ana C. J. de Araújo Priscilla R. Freitas Cícera D. de M. Oliveira-Tintino Iêda M. Begnini Ricardo A. Rebelo Luiz E. da Silva Sandro L. Mireski Michele C. Nasato Maria I. L. Krautler Jaime Ribeiro-Filho Henrique D. M. Coutinho Saulo R. Tintino 《Indian journal of microbiology》2021,61(1):100
This study aimed to evaluate the intrinsic antibacterial activity and antibiotic-enhancing effect of an arylamino methylene derivative (MAD) in association with fluoroquinolones. The antibacterial activity against multiresistant Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli was analyzed by determining the minimum inhibitory concentration (MIC) using the broth micro dilution method. A reduction in the MIC of the fluoroquinolones against strains treated simultaneously with the MAD was interpreted as an enhanced antibiotic activity. While the MAD exhibited no clinically effective action (MIC ≥ 1.024 µg/mL), it was found to significantly potentiate the activity of norfloxacin, ofloxacin and lomefloxacin against all the strains, which may be related to structural similarities between the MAD and quinolones. Our findings suggest that Meldrum’s acid arylamino derivatives may represent promising molecules in the elaboration of new drugs to reverse resistance to fluoroquinolones. 相似文献
946.
Nina M van Sorge Daniel A Bonsor Liwen Deng Erik Lindahl Verena Schmitt Mykola Lyndin Alexej Schmidt Olof R Nilsson Jaime Brizuela Elena Boero Eric J Sundberg Jos A G van Strijp Kelly S Doran Bernhard B Singer Gunnar Lindahl Alex J McCarthy 《The EMBO journal》2021,40(7)
Streptococcus agalactiae, also known as group B Streptococcus (GBS), is the major cause of neonatal sepsis in humans. A critical step to infection is adhesion of bacteria to epithelial surfaces. GBS adhesins have been identified to bind extracellular matrix components and cellular receptors. However, several putative adhesins have no host binding partner characterised. We report here that surface‐expressed β protein of GBS binds to human CEACAM1 and CEACAM5 receptors. A crystal structure of the complex showed that an IgSF domain in β represents a novel Ig‐fold subtype called IgI3, in which unique features allow binding to CEACAM1. Bioinformatic assessment revealed that this newly identified IgI3 fold is not exclusively present in GBS but is predicted to be present in adhesins from other clinically important human pathogens. In agreement with this prediction, we found that CEACAM1 binds to an IgI3 domain found in an adhesin from a different streptococcal species. Overall, our results indicate that the IgI3 fold could provide a broadly applied mechanism for bacteria to target CEACAMs. 相似文献
947.
Suzana Vieira Rabêlo Fernanda Granja da Silva Oliveira Michele Miriam Calixto de Lira Livia Macedo Dutra Adilson Sartoratto Marta Cristina Teixeira Duarte Maria Claudia dos Santos Luciano Maria Francilene Souza Silva Cláudia do Ó Pessoa Manoel Odorico de Moraes Filho Emmanoel Vilaça Costa Jackson Roberto Guedes da Silva Almeida 《Phyton》2021,90(3):921-931
This study aimed to identify the chemical composition of essential oil from fruits (EOAF) and the hexanic crude
extract from aerial parts (At-Hex) of atemoya (Annona cherimola x Annona squamosa), a hybrid belonging to the
Annonaceae family. Cytotoxic and antimicrobial activity was also evaluated. OEAF was obtained by hydrodistillation using a Clevenger apparatus, and their composition was analyzed by gas chromatography-mass spectrometry
(GC-MS) analyses. Cytotoxicity was tested against human tumor cell lines HCT-116 (colon carcinoma), SF-295
(glioblastoma), OVCAR-8 (ovarian carcinoma) and HL60 (leukemia) using 3-(4,5-dimethyl-2-thiazolyl)-2,5-
diphenyl-2H-tetrazolium bromide (MTT) assay, while antimicrobial activity was conducted by bioauthography
method against eleven microorganisms strains. Twenty-four compounds were identified in the EOAF and
twenty-nine in At-Hex. The monoterpenes linalool (25.70%), α-pinene (10.38%), β-pinene (9.12%), transocimene (7.43%), and the sesquiterpene bicyclogermacrene (12.58%) were the major constituents of EOAF,
whereas the sesquiterpene spathulenol (13.91%) was the main compound of At-Hex. At-Hex showed a high
cytotoxicity against SF-295 (glioblastoma). These findings show an important chemotaxonomic contribution
for the Annonaceae family, mainly for the Annona genus. Atemoya proved to be a promising source of substances
with potential cytotoxic activity. 相似文献
948.
949.
Jomaa A Stewart G Martín-Benito J Zielke R Campbell TL Maddock JR Brown ED Ortega J 《RNA (New York, N.Y.)》2011,17(4):697-709
Four decades after early in vitro assembly studies demonstrated that ribosome assembly is a controlled process, our understanding of ribosome assembly is still incomplete. Just as structure determination has been so important to understanding ribosome function, so too will it be critical to sorting out the assembly process. Here, we used a viable deletion in the yjeQ gene, a recognized ribosome assembly factor, to isolate and structurally characterize immature 30S subunits assembled in vivo. These small ribosome subunits contained unprocessed 17S rRNA and lacked some late ribosomal proteins. Cryo-electron microscopy reconstructions revealed that the presence of precursor sequences in the rRNA induces a severe distortion in the 3' minor domain of the subunit involved in the decoding of mRNA and interaction with the large ribosome subunit. These findings suggest that rRNA processing events induce key local conformational changes directing the structure toward the mature assembly. We concluded that rRNA processing, folding, and the entry of tertiary r-proteins are interdependent events in the late stages of 30S subunit assembly. In addition, we demonstrate how studies of emerging assembly factors in ribosome biogenesis can help to elucidate the path of subunit assembly in vivo. 相似文献
950.
Mónica E. Riojas‐López Eric Mellink Francis Raoul Jaime Luévano Amélie Vaniscotte Patrick Giraudoux 《Diversity & distributions》2011,17(4):739-747
Aim The Llanos de Ojuelos in Mexico’s Central High Plateau supports unique Opuntia scrublands and the southernmost Chihuahuan grasslands. Although human activities have modified strongly its landscape and impacted its biodiversity at an unknown scale, such impacts are poorly known. We aimed at understanding how nocturnal rodent species distributed across the landscape and formed assemblages and on the role and integration of the different habitats at the landscape level. Location The study was carried out at 43 sites in a study area of approximately 3350 km2 in the Llanos de Ojuelos. Methods During the Spring of 2008, we surveyed nocturnal rodents, through live‐trapping. We redefined habitat classes based on log‐linear multinomial regressions of rodent captures. Species rarefaction curves and true alpha, beta and gamma diversities were calculated for the different habitat classes. A map of the different habitats was constructed based on Landsat imagery. Results We captured 458 individuals of 20 rodent species. Multinomial regressions caused the merger of 11 a priori defined habitat classes into 7. Leguminous scrub and mixed nopaleras, both secondary habitats, had the highest alpha and gamma diversity values. Closed arboreal nopaleras and grasslands had the highest within‐habitat variability (1Dβ) and the lowest area coverage. Within‐habitat 1Dβ was larger than landscape 1Dβ, because of the great overlap in rodent assemblage composition between the habitats. Main conclusions There are no ‘typical’ rodent assemblages per habitat class, but they are organized loosely and have fuzzy borders. Rodent community organization was highly species‐centred. At the landscape level, secondary habitats have a profound effect on rodent diversity and should be included in management schemes for biological conservation. The most endangered habitats seem to be the closed arboreal nopaleras and grasslands. Any conservation efforts must consider their conservation and an increase in the size of remaining patches. 相似文献