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1.
Proc Biol Sci ; 291(2026): 20240804, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38955230

RESUMO

The evolution of nuptial gifts has traditionally been considered a harmonious affair, providing benefits to both mating partners. There is growing evidence, however, that receiving a nuptial gift can be actively detrimental to the female. In decorated crickets (Gryllodes sigillatus), males produce a gelatinous spermatophylax that enhances sperm transfer but provides little nutritional benefit and hinders female post-copulatory mate choice. Here, we examine the sexually antagonistic coevolution of the spermatophylax and the female feeding response to this gift in G. sigillatus maintained in experimental populations with either a male-biased or female-biased adult sex ratio. After 25 generations, males evolving in male-biased populations produced heavier spermatophylaxes with a more manipulative combination of free amino acids than those evolving in female-biased populations. Moreover, when the spermatophylax originated from the same selection regime, females evolving in male-biased populations always had shorter feeding durations than those evolving in female-biased populations, indicating the evolution of greater resistance. Across populations, female feeding duration increased with the mass and manipulative combination of free amino acids in the spermatophylax, suggesting sexually antagonistic coevolution. Collectively, our work demonstrates a key role for interlocus sexual conflict and sexually antagonistic coevolution in the mating system of G. sigillatus.


Assuntos
Comportamento Alimentar , Gryllidae , Comportamento Sexual Animal , Animais , Gryllidae/fisiologia , Masculino , Feminino , Coevolução Biológica , Evolução Biológica , Razão de Masculinidade
2.
Proc Biol Sci ; 290(1991): 20222068, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36651049

RESUMO

In a variety of aposematic species, the conspicuousness of an individual's warning signal and the quantity of its chemical defence are positively correlated. This apparent honest signalling is predicted by resource competition models which assume that the production and maintenance of aposematic defences compete for access to antioxidant molecules that have dual functions as pigments and in protecting against oxidative damage. To test for such trade-offs, we raised monarch butterflies (Danaus plexippus) on different species of their milkweed host plants (Apocynaceae) that vary in quantities of cardenolides to test whether (i) the sequestration of cardenolides as a secondary defence is associated with costs in the form of oxidative lipid damage and reduced antioxidant defences; and (ii) lower oxidative state is associated with a reduced capacity to produce aposematic displays. In male monarchs conspicuousness was explained by an interaction between oxidative damage and sequestration: males with high levels of oxidative damage became less conspicuous with increased sequestration of cardenolides, whereas those with low oxidative damage became more conspicuous with increased levels of cardenolides. There was no significant effect of oxidative damage or concentration of sequestered cardenolides on female conspicuousness. Our results demonstrate a physiological linkage between the production of coloration and oxidative state, and differential costs of sequestration and signalling in monarch butterflies.


Assuntos
Asclepias , Borboletas , Toxinas Biológicas , Animais , Masculino , Borboletas/fisiologia , Larva/fisiologia , Antioxidantes , Asclepias/química , Cardenolídeos , Estresse Oxidativo
3.
J Evol Biol ; 36(9): 1266-1281, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37534753

RESUMO

Although many theoretical models of male sexual trait evolution assume that sexual selection is countered by natural selection, direct empirical tests of this assumption are relatively uncommon. Cuticular hydrocarbons (CHCs) are known to play an important role not only in restricting evaporative water loss but also in sexual signalling in most terrestrial arthropods. Insects adjusting their CHC layer for optimal desiccation resistance is often thought to come at the expense of successful sexual attraction, suggesting that natural and sexual selection are in opposition for this trait. In this study, we sampled the CHCs of male black field crickets (Teleogryllus commodus) using solid-phase microextraction and then either measured their evaporative water loss or mating success. We then used multivariate selection analysis to quantify the strength and form of natural and sexual selection targeting male CHCs. Both natural and sexual selection imposed significant linear and stabilizing selection on male CHCs, although for very different combinations. Natural selection largely favoured an increase in the total abundance of CHCs, especially those with a longer chain length. In contrast, mating success peaked at a lower total abundance of CHCs and declined as CHC abundance increased. However, mating success did improve with an increase in a number of specific CHC components that also increased evaporative water loss. Importantly, this resulted in the combination of male CHCs favoured by natural selection and sexual selection being strongly opposing. Our findings suggest that the balance between natural and sexual selection is likely to play an important role in the evolution of male CHCs in T. commodus and may help explain why CHCs are so divergent across populations and species.


Assuntos
Gryllidae , Preferência de Acasalamento Animal , Animais , Masculino , Seleção Sexual , Gryllidae/genética , Beleza , Hidrocarbonetos
4.
Int J Food Sci Nutr ; 74(1): 33-50, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36450698

RESUMO

Disruption of microvascular architecture is a common pathogenic mechanism in the progression of Alzheimer's disease (AD). Given the anti-angiogenic activity of berry (poly)phenols, we investigated whether long-term feeding of Rubus idaeus (raspberries) could ameliorate cerebral microvascular pathology and improve cognition in the APP/PS-1 mouse model of AD. Male C57Bl/6J mice (50 wild type, 50 APP/PS-1) aged 4-months were fed for 24-weeks, with a normal diet enriched with either 100 mg/day glucose (control diet) or supplemented with glucose and freeze-dried anthocyanin-rich (red) or -poor (yellow) raspberries (100 mg/day) and assessed/sampled post intervention. Cerebral microvascular architecture of wild-type mice was characterised by regularly spaced capillaries with uniform diameters, unlike APP/PS-1 transgenic mice which showed dysregulated microvascular architecture. Long-term feeding of raspberries demonstrated limited modulation of microbiota and no substantive effect on microvascular architecture or cognition in either mice model although changes were evident in endogenous cerebral and plasmatic metabolites.


Assuntos
Doença de Alzheimer , Rubus , Masculino , Camundongos , Animais , Frutas , Antocianinas , Camundongos Transgênicos , Suplementos Nutricionais , Cognição
5.
Appl Microbiol Biotechnol ; 106(18): 6003-6016, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35965289

RESUMO

Sophorolipids are glycolipid biosurfactants consisting of a carbohydrate sophorose head with a fatty acid tail and exist in either an acidic or lactonic form. Sophorolipids are gaining interest as potential cancer chemotherapeutics due to their inhibitory effects on a range of tumour cell lines. Currently, most anti-cancer studies reporting the effects of sophorolipids have focused on lactonic preparations with the effects of acidic sophorolipids yet to be elucidated. We produced a 94% pure acidic sophorolipid preparation which proved to be non-toxic to normal human colonic and lung cells. In contrast, we observed a dose-dependent reduction in viability of colorectal cancer lines treated with the same preparation. Acidic sophorolipids induced apoptosis and necrosis, reduced migration, and inhibited colony formation in all cancer cell lines tested. Furthermore, oral administration of 50 mg kg-1 acidic sophorolipids over 70 days to Apcmin+/- mice was well tolerated and resulted in an increased haematocrit, as well as reducing splenic size and red pulp area. Oral feeding did not affect tumour numbers or sizes in this model. This is the first study to show that acidic sophorolipids dose-dependently and specifically reduces colon cancer cell viability in addition to reducing tumour-associated bleeding in the Apcmin+/- mouse model. KEY POINTS: • Acidic sophorolipids are produced by yeast species such as Starmerella bombicola. • Acidic sophorolipids selectively killed colorectal cells with no effect on healthy gut epithelia. • Acidic sophorolipids reduced tumour-associated gut bleed in a colorectal mouse model.


Assuntos
Neoplasias Colorretais , Ácidos Oleicos , Animais , Neoplasias Colorretais/tratamento farmacológico , Glicolipídeos/farmacologia , Hematócrito , Humanos , Camundongos
6.
Med Humanit ; 48(2): 246-252, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34509992

RESUMO

In 1930, the Bermondsey Public Health Department made the rather unusual decision to establish the first municipal foot clinic in Britain. This pioneering and popular clinic was founded at a time when the aims of public health were being renegotiated. Historical discussion of the reconceptualisation of public health in the interwar period typically depicts a paradigm shift in which public health was no longer focused solely on sanitising the physical environment, but was characterised by an additional, separate aim: the development of hygienic behaviour within patients. While this narrative has proved helpful in explaining the emergence of health education between the wars, Bermondsey's foot clinic challenges it somewhat. In essence, the foot clinic was an inventive and multifaceted attempt to treat Bermondsey's rampant poverty. Chiefly, the clinic sought to improve the occupational fitness of the population in an area where most jobs required workers to be stood up all day. In addition, the foot clinic was expected to provoke physiological and spiritual renewal by freeing patients to move more naturally, according to specific contemporary modernist theories of movement. Finally, the architecture of the building which housed the foot clinic was designed to encourage its patients to adopt more hygienic ways of living in their own homes. Thus, the clinic's aims are difficult to compartmentalise into either sanitisation of the lived environment or health education, since it sought to achieve both goals simultaneously. Fundamentally, this integrated approach to public health was rooted in a concept of health that upheld the interconnectedness of individual, communal and environmental well-being.


Assuntos
Pobreza , , Humanos , Saúde Pública
7.
J Proteome Res ; 20(9): 4566-4577, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34428048

RESUMO

Nonreceptor tyrosine kinases (NRTKs) represent an important class of signaling molecules driving diverse cellular pathways. Aberrant expression and hyperphosphorylation of TNK2, an NRTK, have been implicated in multiple cancers. However, the exact proteins and cellular events that mediate phenotypic changes downstream of TNK2 are unclear. Biological systems that employ proximity-dependent biotinylation methods, such as BioID, are being increasingly used to map protein-protein interactions, as they provide increased sensitivity in discovering interaction partners. In this study, we employed stable isotope labeling with amino acids in cell culture and BioID coupled to the biotinylation site identification technology (BioSITe) method that we recently developed to quantitatively explore the interactome of TNK2. By performing a controlled comparative analysis between full-length TNK2 and its truncated counterpart, we were able to not only identify site-level biotinylation of previously well-established TNK2 binders and substrates including NCK1, NCK2, CTTN, and STAT3, but also discover several novel TNK2 interacting partners. We also performed co-immunoprecipitation and immunofluorescence analysis to validate the interaction between TNK2 and CLINT1, a novel TNK2 interacting protein. Overall, this work reveals the power of the BioSITe method coupled to BioID and highlights several molecules that warrant further exploration to assess their functional significance in TNK2-mediated signaling.


Assuntos
Proteínas Tirosina Quinases , Transdução de Sinais , Biotinilação , Ligação Proteica , Proteínas Tirosina Quinases/genética
8.
Genome Res ; 27(10): 1769-1781, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28877962

RESUMO

MicroRNAs are short RNAs that serve as regulators of gene expression and are essential components of normal development as well as modulators of disease. MicroRNAs generally act cell-autonomously, and thus their localization to specific cell types is needed to guide our understanding of microRNA activity. Current tissue-level data have caused considerable confusion, and comprehensive cell-level data do not yet exist. Here, we establish the landscape of human cell-specific microRNA expression. This project evaluated 8 billion small RNA-seq reads from 46 primary cell types, 42 cancer or immortalized cell lines, and 26 tissues. It identified both specific and ubiquitous patterns of expression that strongly correlate with adjacent superenhancer activity. Analysis of unaligned RNA reads uncovered 207 unknown minor strand (passenger) microRNAs of known microRNA loci and 495 novel putative microRNA loci. Although cancer cell lines generally recapitulated the expression patterns of matched primary cells, their isomiR sequence families exhibited increased disorder, suggesting DROSHA- and DICER1-dependent microRNA processing variability. Cell-specific patterns of microRNA expression were used to de-convolute variable cellular composition of colon and adipose tissue samples, highlighting one use of these cell-specific microRNA expression data. Characterization of cellular microRNA expression across a wide variety of cell types provides a new understanding of this critical regulatory RNA species.


Assuntos
MicroRNAs/biossíntese , MicroRNAs/genética , Processamento Pós-Transcricional do RNA/fisiologia , Adulto , Linhagem Celular Transformada , Linhagem Celular Tumoral , Humanos , Masculino , Especificidade de Órgãos
9.
Genome Res ; 27(1): 133-144, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28003436

RESUMO

Complementing genome sequence with deep transcriptome and proteome data could enable more accurate assembly and annotation of newly sequenced genomes. Here, we provide a proof-of-concept of an integrated approach for analysis of the genome and proteome of Anopheles stephensi, which is one of the most important vectors of the malaria parasite. To achieve broad coverage of genes, we carried out transcriptome sequencing and deep proteome profiling of multiple anatomically distinct sites. Based on transcriptomic data alone, we identified and corrected 535 events of incomplete genome assembly involving 1196 scaffolds and 868 protein-coding gene models. This proteogenomic approach enabled us to add 365 genes that were missed during genome annotation and identify 917 gene correction events through discovery of 151 novel exons, 297 protein extensions, 231 exon extensions, 192 novel protein start sites, 19 novel translational frames, 28 events of joining of exons, and 76 events of joining of adjacent genes as a single gene. Incorporation of proteomic evidence allowed us to change the designation of more than 87 predicted "noncoding RNAs" to conventional mRNAs coded by protein-coding genes. Importantly, extension of the newly corrected genome assemblies and gene models to 15 other newly assembled Anopheline genomes led to the discovery of a large number of apparent discrepancies in assembly and annotation of these genomes. Our data provide a framework for how future genome sequencing efforts should incorporate transcriptomic and proteomic analysis in combination with simultaneous manual curation to achieve near complete assembly and accurate annotation of genomes.


Assuntos
Genoma/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Anotação de Sequência Molecular , Transcriptoma/genética , Animais , Anopheles/genética , Éxons/genética , Perfilação da Expressão Gênica , Proteoma/genética , Proteômica
10.
J Evol Biol ; 33(7): 990-1005, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32281707

RESUMO

A major challenge for studying the role of sexual selection in divergence and speciation is understanding the relative influence of different sexually selected signals on those processes in both intra- and interspecific contexts. Different signals may be more or less susceptible to co-option for species identification depending on the balance of sexual and ecological selection acting upon them. To examine this, we tested three predictions to explain geographic variation in long- versus short-range sexual signals across a 3,500 + km transect of two related Australian field cricket species (Teleogryllus spp.): (a) selection for species recognition, (b) environmental adaptation and (c) stochastic divergence. We measured male calling song and male and female cuticular hydrocarbons (CHCs) in offspring derived from wild populations, reared under common garden conditions. Song clearly differentiated the species, and no hybrids were observed suggesting that hybridization is rare or absent. Spatial variation in song was not predicted by geography, genetics or climatic factors in either species. In contrast, CHC divergence was strongly associated with an environmental gradient supporting the idea that the climatic environment selects more directly upon these chemical signals. In light of recently advocated models of diversification via ecological selection on secondary sexual traits, the different environmental associations we found for song and CHCs suggest that the impact of ecological selection on population divergence, and how that influences speciation, might be different for acoustic versus chemical signals.


Assuntos
Comunicação Animal , Gryllidae/genética , Isolamento Reprodutivo , Comportamento Sexual Animal , Seleção Sexual , Adaptação Biológica , Animais , Clima , Feminino , Gryllidae/química , Hidrocarbonetos/química , Masculino , Especificidade da Espécie
11.
J Evol Biol ; 32(3): 243-258, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30485577

RESUMO

Speciation research dissects the genetics and evolution of reproductive barriers between parental species. Hybrids are the "gatekeepers" of gene flow, so it is also important to understand the behavioural mechanisms and genetics of any potential isolation from their parental species. We tested the role of multiple behavioural barriers in reproductive isolation among closely related field crickets and their hybrids (Teleogryllus oceanicus and Teleogryllus commodus). These species hybridize in the laboratory, but the behaviour of hybrids is unusual and there is little evidence for gene flow in the wild. We found that heterospecific pairs exhibited reduced rates of courtship behaviour due to discrimination by both sexes, and that this behavioural isolation was symmetrical. However, hybrids were not sexually selected against and exhibited high rates of courtship behaviour even though hybrid females are sterile. Using reciprocal hybrid crosses, we characterized patterns of interspecific divergence and inheritance in key sexual traits that might underlie the mating patterns we found: calling song, courtship song and cuticular hydrocarbons (CHCs). Song traits exhibited both sex linkage and transgressive segregation, whereas CHCs exhibited only the latter. Calculations of the strength of isolation exerted by these sexual traits suggest that close-range signals are as important as long-distance signals in contributing to interspecific sexual isolation. The surprisingly weak mating barriers observed between hybrids and parental species highlight the need to examine reproductive isolating mechanisms and their genetic bases across different potential stages of introgressive hybridization.


Assuntos
Comunicação Animal , Gryllidae , Hibridização Genética , Isolamento Reprodutivo , Comportamento Sexual Animal , Animais , Feminino , Gryllidae/genética , Masculino
12.
J Chem Ecol ; 45(9): 798-807, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31422515

RESUMO

The koala is a specialist feeder with a diet consisting almost exclusively of potentially toxic eucalypt leaves. Monoterpenes, an abundant class of plant secondary metabolites in eucalypts, are highly lipophilic. Chronic absorption and systemic exposure can be anticipated for the koala, causing health effects in various ways when consumed in high amounts, but particularly causing alterations in immune function in this species. Therefore, careful leaf selection, efficient detoxification pathways, and other specialist adaptations are required to protect animals from acute intoxication. This is the first paper providing insight into the systemic exposure of koalas to these compounds. Profiles of six selected major monoterpenes were investigated in the ingesta of deceased koalas from four different regions of NSW and South-East Queensland. Concentrations of the same compounds were measured in lymphoid tissues of deceased koalas and in the blood of live koalas from other regions of NSW. Analytical methods included liquid extraction and solid-phase micro-extraction, followed by gas-chromatography/ mass-spectrometry. Concentrations in the ingesta of individual animals vary remarkably, though the average proportions of individual monoterpenes in the ingesta of animals from the four different regions are highly comparable. Blood concentrations of the selected monoterpenes also varied considerably. The highest blood concentrations were found for 1,8-cineole, up to 971 ng/ml. There was similarity between circulating monoterpene profiles and ingesta profiles. Based on the observed lack of similarity between blood and lymph tissue concentrations, individual monoterpenes either exhibit different affinities for lymphatic tissue compared to blood or their accumulation in blood and lymph tissue differs temporally. In general, blood monoterpene concentrations found in koalas were low compared to those reported in other marsupial eucalypt feeders, but significant concentrations of monoterpenes were detected in all samples analysed. This data on blood and lymphatic tissue monoterpene concentrations builds the fundamental groundwork for future research into the effects of dietary monoterpenes on various biological processes of specialist herbivores and into the significance of these animals' metabolic and behavioural strategies for coping with these compounds. We have shown that the systemic exposure of koalas to potentially anti-inflammatory eucalypt monoterpenes is continuous, and we provide data on physiological concentrations which will allow realistic future studies of the effects of monoterpenes on immune cell function.


Assuntos
Eucalyptus/química , Monoterpenos/química , Phascolarctidae/metabolismo , Folhas de Planta/química , Animais , Austrália , Comportamento Alimentar , Monoterpenos/metabolismo , Phascolarctidae/fisiologia
13.
Mol Cell Proteomics ; 15(8): 2829-38, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27231314

RESUMO

Quantitative mass spectrometry data necessitates an analytical pipeline that captures the accuracy and comprehensiveness of the experiments. Currently, data analysis is often coupled to specific software packages, which restricts the analysis to a given workflow and precludes a more thorough characterization of the data by other complementary tools. To address this, we have developed PyQuant, a cross-platform mass spectrometry data quantification application that is compatible with existing frameworks and can be used as a stand-alone quantification tool. PyQuant supports most types of quantitative mass spectrometry data including SILAC, NeuCode, (15)N, (13)C, or (18)O and chemical methods such as iTRAQ or TMT and provides the option of adding custom labeling strategies. In addition, PyQuant can perform specialized analyses such as quantifying isotopically labeled samples where the label has been metabolized into other amino acids and targeted quantification of selected ions independent of spectral assignment. PyQuant is capable of quantifying search results from popular proteomic frameworks such as MaxQuant, Proteome Discoverer, and the Trans-Proteomic Pipeline in addition to several standalone search engines. We have found that PyQuant routinely quantifies a greater proportion of spectral assignments, with increases ranging from 25-45% in this study. Finally, PyQuant is capable of complementing spectral assignments between replicates to quantify ions missed because of lack of MS/MS fragmentation or that were omitted because of issues such as spectra quality or false discovery rates. This results in an increase of biologically useful data available for interpretation. In summary, PyQuant is a flexible mass spectrometry data quantification platform that is capable of interfacing with a variety of existing formats and is highly customizable, which permits easy configuration for custom analysis.


Assuntos
Proteômica/métodos , Espectrometria de Massas/métodos , Software
14.
Angiogenesis ; 20(4): 567-580, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28741167

RESUMO

Cerebral and systemic organ microvascular pathologies coexist with human Alzheimer's disease (AD) neuropathology. In this study, we hypothesised that both cerebral and systemic microvascular pathologies exist in 4- to 5-month-old male APPswe/PS1dE9 (APP/PS1) transgenic mice prior to the onset of cognitive impairment. To assess this we examined recognition memory in both wild-type and APP/PS1 mice using the object recognition task (ORT; n = 11 per group) and counted thioflavin-S-positive plaques in brain (n = 6 per group). Vascular casts of brain, liver, spleen and kidneys were examined using scanning electron microscopy (n = 6 per group), and the urinary albumin-to-creatinine ratio (uACR; n = 5 per group) was measured as an index of glomerular permeability. Murine recognition memory was intact, as demonstrated by a significant preference for the novel object in the ORT paradigm. Brain sections of wild-type mice were devoid of thioflavin-S positivity, whereas age-matched APP/PS1 mice had an average of 0.88 ± 0.22 thioflavin-S-positive plaques in the cortex, 0.42 ± 0.17 plaques in the dentate gyrus and 0.30 ± 0.07 plaques in the cornus ammonis 1 region. The profiles of casted cerebral capillaries of wild-type mice were smooth and regular in contrast to those of APP/PS1 mice which demonstrate characteristic (0.5-4.6 µm) 'tags'. APP/PS1 mice also had a significantly reduced hepatic vessel number (p = 0.0002) and an increase in the number of splenic microvascular pillars (p = 0.0231), in the absence of changes in either splenic microvascular density (p = 0.3746) or glomerular ultrastructure. The highly significant reduction in uACR in APP/PS1 mice compared to wild-type (p = 0.0079) is consistent with glomerular microvascular dysfunction. These findings highlight early microvascular pathologies in 4- to 5-month-old APP/PS1 transgenic mice and may indicate an amenable target for pharmacological intervention in AD.


Assuntos
Doença de Alzheimer/patologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Microvasos/ultraestrutura , Animais , Benzotiazóis , Capilares/ultraestrutura , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/patologia , Disfunção Cognitiva/complicações , Modelos Animais de Doenças , Comportamento Exploratório , Intussuscepção/complicações , Intussuscepção/patologia , Glomérulos Renais/patologia , Glomérulos Renais/ultraestrutura , Fígado/irrigação sanguínea , Fígado/patologia , Masculino , Memória de Curto Prazo , Camundongos Transgênicos , Microvasos/patologia , Placa Amiloide/patologia , Baço/irrigação sanguínea , Baço/patologia , Tiazóis/metabolismo
15.
Artigo em Inglês | MEDLINE | ID: mdl-28242666

RESUMO

The sophorolipid class of biosurfactants is finding increasing use in personal care as well as pharmaceutical products and has the potential to disrupt biofilm formation and inhibit the growth of a variety of clinically relevant organisms. In order to investigate potential biomedical applications of sophorolipids derived from nonpathogenic organisms, we fractionated and purified glycolipid biosurfactant sophorolipids produced by the yeast Starmerella bombicola, which yielded nonacetylated acidic C18:1 congeners that were essentially free from other contaminants (>95% purity). These acidic sophorolipids have antimicrobial activities against the nosocomial infective agents Enterococcus faecalis and Pseudomonas aeruginosa, with significant reductions in CFU at concentrations of as low as 5 mg ml-1 In addition, the sophorolipid showed similar effects against the same two bacterial strains when combined with kanamycin or cefotaxime. As a potential use of these sophorolipids is as a component of topically applied creams for the treatment of wound infections, it is clear that they must have no demonstrable adverse effect on wound healing. To assess this, we evaluated mammalian cell toxicity in vitro using viability tests, which revealed no adverse effect on either endothelial or keratinocyte-derived cell lines with sophorolipid concentrations of < 0.5 mg ml-1 In addition, in vivo experiments using a mouse skin wounding assay revealed that the time course of healing wounds was unaffected by the application of sophorolipid-containing creams, and histological examination of regenerated skin tissue confirmed that the healing process was similar to that observed for control animals, with no evidence of inflammation. These results are consistent with the suggestion that acidic sophorolipids can be used as a component of antimicrobial creams to reduce the risk of wound infection during healing.


Assuntos
Antibacterianos/farmacologia , Enterococcus faecalis/crescimento & desenvolvimento , Glicolipídeos/farmacologia , Pseudomonas aeruginosa/crescimento & desenvolvimento , Cicatrização/efeitos dos fármacos , Adjuvantes Farmacêuticos/farmacologia , Animais , Cefotaxima/farmacologia , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana , Humanos , Canamicina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Saccharomycetales/metabolismo , Tensoativos/farmacologia
16.
Methods ; 104: 93-100, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-26845462

RESUMO

Mass spectrometry imaging (MSI) is a powerful tool for the study of intact tissue sections. The use of matrix-assisted laser desorption/ionisation (MALDI) MSI for the study of the distribution and effect of emollient treatment on sections of reconstructed living skin equivalents during their development and maturation is described. Living skin equivalent (LSE) samples were obtained at 14days development, re-suspended in maintenance medium and incubated for 24h after delivery. The medium was changed, the LSE treated with either Physiogel A.I.® or Oilatum Junior® emollients and then re-incubated and samples taken at 4, 6 and 24h time points. Mass spectra and mass spectral images were recorded from 12µm sections of the LSE taken at each time point for comparison using MALDI mass spectrometry (MS). It was possible to detect ions characteristic of each emollient in the LSE. In addition a number of lipid species previously reported as being significant in the maturation of the LSE were observable. At the 24h time point, the images revealed what appeared to be differences in the organisation of the skin cells observed across the Physiogel A.I.® treatment group tissue sections when directly compared to the untreated tissue group.


Assuntos
Etanolaminas/química , Lipídeos/isolamento & purificação , Ácidos Palmíticos/química , Pele/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Amidas , Emolientes/efeitos adversos , Emolientes/farmacologia , Etanolaminas/metabolismo , Humanos , Lipídeos/química , Ácidos Palmíticos/metabolismo , Pele/efeitos dos fármacos
17.
Bull Math Biol ; 79(8): 1846-1869, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28620881

RESUMO

When using mathematics to study epidemics, oftentimes the goal is to determine when an infection can invade and persist within a population. The most common way to do so uses threshold quantities called reproductive numbers. An infection's basic reproductive number (BRN), typically denoted [Formula: see text], measures the infection's initial ability to reproduce in a naive population and is tied mathematically to the stability of the disease-free equilibrium. Next-generation methods have long been used to derive [Formula: see text] for autonomous continuous-time systems; however, many diseases exhibit seasonal behavior. Incorporating seasonality into models may improve accuracy in important ways, but the resulting non-autonomous systems are much more difficult to analyze. In the literature, two principal methods have been used to derive BRNs for periodic epidemic models. One, based on time-averages, is simple to apply but does not always describe the correct threshold behavior. The other, based on linear operator theory, is more general but also more complicated, and no detailed explanations of the necessary computations have yet been laid out. This paper reconciles the two methods by laying out an explicit procedure for the second and then identifying conditions (and some important classes of models) under which the two methods agree. This allows the use of the simpler method, which yields interpretable closed-form expressions, when appropriate, and illustrates in detail the simplest possible case where they disagree. Results show that seasonality alone cannot affect disease persistence, but must act in conjunction with non-hierarchical heterogeneity in the infected population, in order to do so.


Assuntos
Epidemias , Modelos Teóricos , Humanos
18.
Genomics ; 108(1): 37-45, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26778813

RESUMO

Long non-coding RNAs (lncRNAs) have been shown to possess a wide range of functions in both cellular and developmental processes including cancers. Although some of the lncRNAs have been implicated in the regulation of the immune response, the exact function of the large majority of lncRNAs still remains unknown. In this study, we characterized the lncRNAs in human primary monocytes, an essential component of the innate immune system. We performed RNA sequencing of monocytes from four individuals and combined our data with eleven other publicly available datasets. Our analysis led to identification of ~8000 lncRNAs of which >1000 have not been previously reported in monocytes. PCR-based validation of a subset of the identified novel long intergenic noncoding RNAs (lincRNAs) revealed distinct expression patterns. Our study provides a landscape of lncRNAs in monocytes, which could facilitate future experimental studies to characterize the functions of these molecules in the innate immune system.


Assuntos
Perfilação da Expressão Gênica/métodos , Monócitos/metabolismo , RNA Longo não Codificante/genética , Análise de Sequência de RNA/métodos , Transcriptoma , Linfócitos B/metabolismo , Sequência de Bases , Mapeamento Cromossômico , Genoma Humano/genética , Humanos , Modelos Genéticos , RNA Longo não Codificante/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/metabolismo , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos T Reguladores/metabolismo
19.
J Urol ; 196(3): 763-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27131463

RESUMO

PURPOSE: We sought to determine perioperative patterns of narcotic use and the prevalence of postoperative doctor shopping among patients with nephrolithiasis requiring operative management. MATERIALS AND METHODS: We retrospectively reviewed the records of consecutive patients residing in Tennessee who required ureteroscopy with laser lithotripsy for nephrolithiasis at a single institution from January to December 2013. Using the Tennessee CSMD (Controlled Substances Medication Database) patients were categorized by the number of postoperative narcotic providers. Doctor shopping behavior was identified as any patient seeking more than 1 narcotic provider within 3 months of surgery. Demographic and clinical characteristics associated with doctor shopping behavior were identified. RESULTS: During the study period 200 eligible patients underwent ureteroscopy with laser lithotripsy for nephrolithiasis, of whom 48 (24%) were prescribed narcotics by more than 1 provider after surgery. Compared to those receiving narcotics from a single provider, patients with multiple narcotic providers were younger (48.1 vs 54.2 years, p <0.001), less educated (high school education or less in 83.3% vs 58.7%, p = 0.014), more likely to have a history of mental illness (37.5% vs 16%, p <0.01) and more likely to have undergone prior stone procedures (66% vs 42%, p <0.01). Additionally, these patients demonstrated more frequent preoperative narcotic use (87.5% vs 63.2%), longer postoperative narcotic use (39.1 vs 6.0 days) and a higher morphine equivalent dose per prescription (44.7 vs 35.2 dose per day, each p <0.001). CONCLUSIONS: Postoperative doctor shopping is common among patients with nephrolithiasis who require operative management. Urologists should be aware of available registry data to decrease the likelihood of redundant narcotic prescribing.


Assuntos
Cálculos Renais/cirurgia , Entorpecentes/uso terapêutico , Manejo da Dor/métodos , Dor Pós-Operatória/tratamento farmacológico , Segurança do Paciente , Médicos , Procedimentos Cirúrgicos Urológicos/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
Blood ; 124(9): 1434-44, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-24957142

RESUMO

Recent genomic studies have provided a refined genetic map of acute lymphoblastic leukemia (ALL) and increased the number of potential prognostic markers. Therefore, we integrated copy-number alteration data from the 8 most commonly deleted genes, subordinately, with established chromosomal abnormalities to derive a 2-tier genetic classification. The classification was developed using 809 ALL97/99 patients and validated using 742 United Kingdom (UK)ALL2003 patients. Good-risk (GR) genetic features included ETV6-RUNX1, high hyperdiploidy, normal copy-number status for all 8 genes, isolated deletions affecting ETV6/PAX5/BTG1, and ETV6 deletions with a single additional deletion of BTG1/PAX5/CDKN2A/B. All other genetic features were classified as poor risk (PR). Three-quarters of UKALL2003 patients had a GR genetic profile and a significantly improved event-free survival (EFS) (94%) compared with patients with a PR genetic profile (79%). This difference was driven by a lower relapse rate (4% vs 17%), was seen across all patient subgroups, and was independent of other risk factors. Even genetic GR patients with minimal residual disease (>0.01%) at day 29 had an EFS in excess of 90%. In conclusion, the integration of genomic and cytogenetic data defines 2 subgroups with distinct responses to treatment and identifies a large subset of children suitable for treatment deintensification.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Análise Citogenética , Feminino , Deleção de Genes , Dosagem de Genes , Genes p16 , Genômica , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Fator de Transcrição PAX5/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/classificação , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Prognóstico , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Repressoras/genética , Fatores de Risco , Variante 6 da Proteína do Fator de Translocação ETS
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