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41.
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Stanford Splitter Frederick R. Brown Jr. Roger W. Friskey Lois Grindle Laurance W. Kinsell 《The Western journal of medicine》1956,85(5):285-288
Of a group of 32 patients with diabetes, 26 had a favorable modification of the disease in response to administration of butyl-sulfonyl-urea. All but one of the patients who had good response were past the age of 38. All diabetic patients included in this group were those with little or no tendency to ketosis after cessation of insulin administration. No toxic manifestations were noted except for a slight decrease in leukocytes in one case. 相似文献
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In vitro fertilization has overcome infertility issues for many couples. However, achieving implantation of a viable embryo into the maternal endometrium remains a limiting step in optimizing pregnancy success. The molecular mechanisms which characterize the transient state of endometrial receptivity, critical in enabling embryo‐endometrial interactions, and proteins which underpin adhesion at the implantation interface, are limited in humans despite these temporally regulated processes fundamental to life. Hence, failure of implantation remains the “final frontier” in infertility. A human coculture model is utilized utilizing spheroids of a trophectoderm (trophoblast stem) cell line, derived from pre‐implantation human embryos, and primary human endometrial epithelial cells, to functionally identify “fertile” versus “infertile” endometrial epithelium based on adhesion between these cell types. Quantitative proteomics identified proteins associated with human endometrial epithelial receptivity (“epithelial receptome”) and trophectoderm adhesion (“adhesome”). As validation, key “epithelial receptome” proteins (MAGT‐1/CDA/LGMN/KYNU/PC4) localized to the epithelium of receptive phase (mid‐secretory) endometrium obtained from fertile, normally cycling women but is largely absent from non‐receptive (proliferative) phase tissues. Factors involved in embryo‐epithelium interaction in successive temporal stages of endometrial receptivity and implantation are demonstrated and potential targets for improving fertility are provided, enhancing potential to become pregnant either naturally or in a clinical setting. 相似文献
45.
Nicols A. Lois Leonardo Campagna Ulises Balza Michael J. Polito Klemens Pütz Juliana A. Vianna Annick Morgenthaler Esteban Frere Ricardo Senz‐Samaniego Andrea Raya Rey Bettina Mahler 《Ecology and evolution》2020,10(7):3346-3355
Population connectivity is driven by individual dispersal potential and modulated by natal philopatry. In seabirds, high vagility facilitates dispersal yet philopatry is also common, with foraging area overlap often correlated with population connectivity. We assess the interplay between these processes by studying past and current connectivity and foraging niche overlap among southern rockhopper penguin colonies of the coast of southern South America using genomic and stable isotope analyses. We found two distinct genetic clusters and detected low admixture between northern and southern colonies. Stable isotope analysis indicated niche variability between colonies, with Malvinas/Falklands colonies encompassing the species entire isotopic foraging niche, while the remaining colonies had smaller, nonoverlapping niches. A recently founded colony in continental Patagonia differed in isotopic niche width and position with Malvinas/Falklands colonies, its genetically identified founder population, suggesting the exploitation of novel foraging areas and/or prey items. Additionally, dispersing individuals found dead across the Patagonian shore in an unusual mortality event were also assigned to the northern cluster, suggesting northern individuals reach southern localities, but do not breed in these colonies. Facilitated by variability in foraging strategies, and especially during unfavorable conditions, the number of dispersing individuals may increase and enhance the probability of founding new colonies. Metapopulation demographic dynamics in seabirds should account for interannual variability in dispersal behavior and pay special attention to extreme climatic events, classically related to negative effects on population trends. 相似文献
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Positive species interactions such as facilitation are important for enabling species to persist, especially in stressful conditions, and the nature and strength of facilitation varies along physical and biological gradients. Expansion of coastal infrastructure is creating hotspots of invasive species which can spillover into natural habitats, but the role of positive species interactions associated with biological invasions remains understudied. Theory suggests that stronger biotic pressure in natural habitats inhibits invasion success. In space-limited marine systems, sessile organisms can overcome this limiting resource by settling as an epibiont on a substrate organism – basibiont. Using a series of spatially extensive surveys, we explored the role of invasive and native basibionts in providing habitat for other invasive and native epibionts, and tested whether environmental context (i.e. if the receiving habitat was natural or artificial), altered ecological outcomes. Overall, provision of space by basibionts was more important for invasive epibionts than for native epibionts but was dependent on the environmental context. Invasive basibionts facilitated invasive epibionts in natural habitats, and appeared to be more important for native epibionts in artificial habitats respectively. Native basibionts facilitated invasive, but not native epibionts in both natural and artificial habitats. These results advance our understanding of facilitation and highlight the idiosyncratic nature of biofouling and epibiosis, and the potentially important influence of environmental context. The degree to which native habitat-forming species versus invasive habitat-forming species either do or do not facilitate other native or non-native species is a rich area for investigation. Experimental work is required to disentangle the processes underpinning these patterns. 相似文献
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Jonathan M. Behrendt David Nagel Evita Chundoo Lois M. Alexander Damien Dupin Anna V. Hine Mark Bradley Andrew J. Sutherland 《PloS one》2013,8(3)
The efficient transport of micron-sized beads into cells, via a non-endocytosis mediated mechanism, has only recently been described. As such there is considerable scope for optimization and exploitation of this procedure to enable imaging and sensing applications to be realized. Herein, we report the design, synthesis and characterization of fluorescent microsphere-based cellular delivery agents that can also carry biological cargoes. These core-shell polymer microspheres possess two distinct chemical environments; the core is hydrophobic and can be labeled with fluorescent dye, to permit visual tracking of the microsphere during and after cellular delivery, whilst the outer shell renders the external surfaces of the microspheres hydrophilic, thus facilitating both bioconjugation and cellular compatibility. Cross-linked core particles were prepared in a dispersion polymerization reaction employing styrene, divinylbenzene and a thiol-functionalized co-monomer. These core particles were then shelled in a seeded emulsion polymerization reaction, employing styrene, divinylbenzene and methacrylic acid, to generate orthogonally functionalized core-shell microspheres which were internally labeled via the core thiol moieties through reaction with a thiol reactive dye (DY630-maleimide). Following internal labeling, bioconjugation of green fluorescent protein (GFP) to their carboxyl-functionalized surfaces was successfully accomplished using standard coupling protocols. The resultant dual-labeled microspheres were visualized by both of the fully resolvable fluorescence emissions of their cores (DY630) and shells (GFP). In vitro cellular uptake of these microspheres by HeLa cells was demonstrated conventionally by fluorescence-based flow cytometry, whilst MTT assays demonstrated that 92% of HeLa cells remained viable after uptake. Due to their size and surface functionalities, these far-red-labeled microspheres are ideal candidates for in vitro, cellular delivery of proteins. 相似文献
48.
Jordi Morata Santi Béjar David Talavera Casandra Riera Sergio Lois Gemma Mas de Xaxars Xavier de la Cruz 《PloS one》2013,8(8)
At present we know that phenotypic differences between organisms arise from a variety of sources, like protein sequence divergence, regulatory sequence divergence, alternative splicing, etc. However, we do not have yet a complete view of how these sources are related. Here we address this problem, studying the relationship between protein divergence and the ability of genes to express multiple isoforms. We used three genome-wide datasets of human-mouse orthologs to study the relationship between isoform multiplicity co-occurrence between orthologs (the fact that two orthologs have more than one isoform) and protein divergence. In all cases our results showed that there was a monotonic dependence between these two properties. We could explain this relationship in terms of a more fundamental one, between exon number of the largest isoform and protein divergence. We found that this last relationship was present, although with variations, in other species (chimpanzee, cow, rat, chicken, zebrafish and fruit fly). In summary, we have identified a relationship between protein divergence and isoform multiplicity co-occurrence and explained its origin in terms of a simple gene-level property. Finally, we discuss the biological implications of these findings for our understanding of inter-species phenotypic differences. 相似文献
49.
York Hunt Ng Sophie Rome Audrey Jalabert Alexis Forterre Harmeet Singh Cassandra L. Hincks Lois A. Salamonsen 《PloS one》2013,8(3)
Exosomes are nanoparticles (∼100 nm diameter) released from cells, which can transfer small RNAs and mRNA via the extracellular environment to cells at distant sites. We hypothesised that exosomes or the slightly larger microvesicles (100–300 nm) are released from the endometrial epithelium into the uterine cavity, and that these contain specific micro (mi)RNA that could be transferred to either the trophectodermal cells of the blastocyst or to endometrial epithelial cells, to promote implantation. The aim of this study was to specifically identify and characterise exosomes/microvesicles (mv) released from endometrial epithelial cells and to determine whether exosomes/mv are present in uterine fluid. Immunostaining demonstrated that the tetraspanins, CD9 and CD63 used as cell surface markers of exosomes are present on the apical surfaces of endometrial epithelial cells in tissue sections taken across the menstrual cycle: CD63 showed cyclical regulation. Exosome/mv pellets were prepared from culture medium of endometrial epithelial cell (ECC1 cells) and from uterine fluid and its associated mucus by sequential ultracentifugation. Exosomes/mv were positively identified in all preparations by FACS and immunofluorescence staining following exosome binding to beads. Size particle analysis confirmed the predominance of particles of 50–150 nm in each of these fluids. MiRNA analysis of the ECC1 cells and their exosomes/mv demonstrated sorting of miRNA into exosomes/mv: 13 of the 227 miRNA were specific to exosomes/mv, while a further 5 were not present in these. The most abundant miRNA in exosomes/mv were hsa-miR-200c, hsa-miR-17 and hsa-miR-106a. Bioinformatic analysis showed that the exosome/mv-specific miRNAs have potential targets in biological pathways highly relevant for embryo implantation. Thus exosomes/mv containing specific miRNA are present in the microenvironment in which embryo implantation occurs and may contribute to the endometrial-embryo cross talk essential for this process. 相似文献
50.