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41.
Ants are powerful model systems for the study of cooperation and sociality. In this review, we discuss how recent advances in ant genomics have contributed to our understanding of the evolution and organization of insect societies at the molecular level. 相似文献
42.
Hernández-Ledesma Ana Laura Rodríguez-Méndez Adriana Jheny Gallardo-Vidal Lilia Susana García-Gasca Teresa Alatorre-Cruz Julia María García-Solís Pablo López Reyes Julián Solís-Saínz Juan Carlos 《Molecular biology reports》2020,47(12):9667-9676
Molecular Biology Reports - Although cognitive impairment (CI) is classically associated with aging, it has been proposed that neurological pathologies may increase the risk to suffer CI. Despite... 相似文献
43.
Chiral sulfoxides/N‐oxides (R)‐ 1 and (R,R)‐ 2 are effective chiral promoters in the enantioselective allylation of α‐keto ester N‐benzoylhydrazone derivatives 3a , 3b , 3c , 3d , 3e , 3f , 3g to generate the corresponding N‐benzoylhydrazine derivatives 4a , 4b , 4c , 4d , 4e , 4f , 4g , with enantiomeric excesses as high as 98%. Representative hydrazine derivatives 4a , 4b were subsequently treated with SmI2, and the resulting amino esters 5a , 5b with LiOH to obtain quaternary α‐substituted α‐allyl α‐amino acids 6a , 6b , whose absolute configuration was assigned as (S), with fundament on chemical correlation and electronic circular dichroism (ECD) data. Chirality 25:529–540, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
44.
Jose-Luis Reyes Hernandez Gabriella Leung Derek M. McKay 《International journal for parasitology》2013,43(3-4):233-243
Helminth parasites are masters of immune regulation; a likely prerequisite for long-term survival by circumventing their hosts’ attempt to eradicate them. From a translational perspective, knowledge of immune events as a response to infection with a helminth parasite could be used to reduce the intensity of unwanted inflammatory reactions. Substantial data have accumulated showing that inflammatory reactions that promote a variety of auto-inflammatory diseases are dampened as a consequence of infection with helminth parasites, via either the mobilization of an anti-worm spectrum of immune events or by the direct effect of secretory/excretory bioactive immunomodulatory molecules released from the parasite. However, many issues are outstanding in the definition of the mechanism(s) by which infection with helminth parasites can affect the outcome, positively or negatively, of concomitant disease. We focus on a subgroup of this complex group of metazoan parasites, the cestodes, summarizing studies from rodent models that illustrate if, and by what mechanisms, infection with tapeworms ameliorate or exaggerate disease in their host. The ability of infection with cestodes, or other classes of helminth, to worsen a disease course or confer susceptibility to intracellular pathogens should be carefully considered in the context of ‘helminth therapy’. In addition, poorly characterised cestode extracts can regulate murine and human immunocyte function, yet the impact of these in the context of autoimmune or allergic diseases is poorly understood. Thus, studies with cestodes, as representative helminths, have helped cement the concept that infection with parasitic helminths can inhibit concomitant disease; however, issues relating to long-term effects, potential side-effects, mixed pathogen infections and purification of immunomodulatory molecules from the parasite remain as challenges that need to be addressed in order to achieve the use of helminths as anti-inflammatory agents for human diseases. 相似文献
45.
46.
Quantification of Anti‐Addictive Alkaloids Ibogaine and Voacangine in In Vivo‐ and In Vitro‐Grown Plants of Two Mexican Tabernaemontana Species 下载免费PDF全文
Felix Krengel Josefina Herrera Santoyo Teresa de Jesús Olivera Flores Víctor M. Chávez Ávila Francisco J. Pérez Flores Ricardo Reyes Chilpa 《化学与生物多样性》2016,13(12):1730-1737
Tabernaemontana alba and Tabernaemontana arborea are Apocynaceae species used in Mexican traditional medicine for which little phytochemical information exists. In this study, preliminary gas chromatography/mass spectrometry analyses of different organs obtained from wild plants of both species identified a total of 10 monoterpenoid indole alkaloids (MIAs) and one simple indole alkaloid, nine of which were reported for the first time in these species. Furthermore, callus cultures were established from T. alba leaf explants and regeneration of whole plants was accomplished via somatic embryogenesis. The anti‐addictive MIAs ibogaine and voacangine were then quantified by gas chromatography with flame ionization detection in wild plants of both species, as well as greenhouse‐grown plants, in vitro‐grown plantlets and embryogenic callus of T. alba. Ibogaine and voacangine were present in most samples taken from the whole plants of both species, with stem and root barks showing the highest concentrations. No alkaloids were detected in callus samples. It was concluded that T. alba and T. arborea are potentially viable sources of ibogaine and voacangine, and that these MIAs can be produced through somatic embryogenesis and whole plant regeneration of T. alba. Approaches to increase MIA yields in whole plants and to achieve alkaloid production directly in cell cultures are discussed. 相似文献
47.
High‐fat diet exacerbates pain‐like behaviors and periarticular bone loss in mice with CFA‐induced knee arthritis 下载免费PDF全文
Aleyda A. Loredo‐Pérez Carlos E. Montalvo‐Blanco Luis I. Hernández‐González Maricruz Anaya‐Reyes Cecilia Fernández del Valle‐Laisequilla Juan G. Reyes‐García Rosa I. Acosta‐González Arisai Martínez‐Martínez Jaira C. Villarreal‐Salcido Virginia M. Vargas‐Muñoz Enriqueta Muñoz‐Islas Martha B. Ramírez‐Rosas Juan M. Jiménez‐Andrade 《Obesity (Silver Spring, Md.)》2016,24(5):1106-1115
48.
Nicole Porz Simon Habegger Raphael Meier Rajeev Verma Astrid Jilch Jens Fichtner Urspeter Knecht Christian Radina Philippe Schucht Jürgen Beck Andreas Raabe Johannes Slotboom Mauricio Reyes Roland Wiest 《PloS one》2016,11(11)
ObjectiveComparison of a fully-automated segmentation method that uses compartmental volume information to a semi-automatic user-guided and FDA-approved segmentation technique.MethodsNineteen patients with a recently diagnosed and histologically confirmed glioblastoma (GBM) were included and MR images were acquired with a 1.5 T MR scanner. Manual segmentation for volumetric analyses was performed using the open source software 3D Slicer version 4.2.2.3 (www.slicer.org). Semi-automatic segmentation was done by four independent neurosurgeons and neuroradiologists using the computer-assisted segmentation tool SmartBrush® (referred to as SB), a semi-automatic user-guided and FDA-approved tumor-outlining program that uses contour expansion. Fully automatic segmentations were performed with the Brain Tumor Image Analysis (BraTumIA, referred to as BT) software. We compared manual (ground truth, referred to as GT), computer-assisted (SB) and fully-automated (BT) segmentations with regard to: (1) products of two maximum diameters for 2D measurements, (2) the Dice coefficient, (3) the positive predictive value, (4) the sensitivity and (5) the volume error.ResultsSegmentations by the four expert raters resulted in a mean Dice coefficient between 0.72 and 0.77 using SB. BT achieved a mean Dice coefficient of 0.68. Significant differences were found for intermodal (BT vs. SB) and for intramodal (four SB expert raters) performances. The BT and SB segmentations of the contrast-enhancing volumes achieved a high correlation with the GT. Pearson correlation was 0.8 for BT; however, there were a few discrepancies between raters (BT and SB 1 only). Additional non-enhancing tumor tissue extending the SB volumes was found with BT in 16/19 cases. The clinically motivated sum of products of diameters measure (SPD) revealed neither significant intermodal nor intramodal variations. The analysis time for the four expert raters was faster (1 minute and 47 seconds to 3 minutes and 39 seconds) than with BT (5 minutes).ConclusionBT and SB provide comparable segmentation results in a clinical setting. SB provided similar SPD measures to BT and GT, but differed in the volume analysis in one of the four clinical raters. A major strength of BT may its independence from human interactions, it can thus be employed to handle large datasets and to associate tumor volumes with clinical and/or molecular datasets ("-omics") as well as for clinical analyses of brain tumor compartment volumes as baseline outcome parameters. Due to its multi-compartment segmentation it may provide information about GBM subcompartment compositions that may be subjected to clinical studies to investigate the delineation of the target volumes for adjuvant therapies in the future. 相似文献
49.
José L. Reyes Maria R. Fernando Fernando Lopes Gabriella Leung Nicole L. Mancini Chelsea E. Matisz Arthur Wang Derek M. McKay 《PLoS pathogens》2016,12(4)
Interleukin (IL)-22, an immune cell-derived cytokine whose receptor expression is restricted to non-immune cells (e.g. epithelial cells), can be anti-inflammatory and pro-inflammatory. Mice infected with the tapeworm Hymenolepis diminuta are protected from dinitrobenzene sulphonic acid (DNBS)-induced colitis. Here we assessed expulsion of H. diminuta, the concomitant immune response and the outcome of DNBS-induced colitis in wild-type (WT) and IL-22 deficient mice (IL-22-/-) ± infection. Interleukin-22-/- mice had a mildly impaired ability to expel the worm and this correlated with reduced or delayed induction of TH2 immunity as measured by splenic and mesenteric lymph node production of IL-4, IL-5 and IL-13 and intestinal Muc-2 mRNA and goblet cell hyperplasia; in contrast, IL-25 increased in the small intestine of IL-22-/- mice 8 and 12 days post-infection compared to WT mice. In vitro experiments revealed that H. diminuta directly evoked epithelial production of IL-25 that was inhibited by recombinant IL-22. Also, IL-10 and markers of regulatory T cells were increased in IL-22-/- mice that displayed less DNBS (3 mg, ir. 72h)-induced colitis. Wild-type mice infected with H. diminuta were protected from colitis, as were infected IL-22-/- mice and the latter to a degree that they were almost indistinguishable from control, non-DNBS treated mice. Finally, treatment with anti-IL-25 antibodies exaggerated DNBS-induced colitis in IL-22-/- mice and blocked the anti-colitic effect of infection with H. diminuta. Thus, IL-22 is identified as an endogenous brake on helminth-elicited TH2 immunity, reducing the efficacy of expulsion of H. diminuta and limiting the effectiveness of the anti-colitic events mobilized following infection with H. diminuta in a non-permissive host. 相似文献
50.
Charmaine B. Mendoza Dan Jethro M. Masacupan Dessa Camille R. Batoctoy Eizadora T. Yu Arturo O. Lluisma Lilibeth A. Salvador‐Reyes 《Journal of peptide science》2019,25(7)
Two conomarphins were purified as the major component of the venom of Conus eburneus. Conomarphins Eb1 and Eb2 showed biological activity in the mollusk Pomacea padulosa, causing sluggishness and retraction of siphon, foot, and cephalic tentacles. To further probe the effects of conserved amino acids and posttranslational modifications in conomarphins, we prepared four synthetic analogues: conomarphin Eb1 Hyp10Pro, Hyp10Ala, d ‐Phe13Ala, and l ‐Phe13 variants. Structure‐activity relationship analysis indicated that d ‐Phe13 is critical to the biological activity of conomarphins. In contrast, amino acid changes at position 10 and removal of posttranslational modification in Hyp10Pro can be tolerated. The high expression level and observed mollusk activity of conomarphins may suggest their potential role as defensive arsenal of Conoidean snails against other predatory gastropods. 相似文献