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This study describes a method for fabricating a superhydrophobic surface on glass via a colloidal deposition technique based on solvent evaporation-induced aggregation. Silica nanoparticles with a low grafting density of long-chain poly(cyclohexyl methacrylate) (PCH) were dispersed in a binary solvent system consisting of tetrahydrofuran (THF) and methanol (MeOH) with an azeotropic point and the nonfluorinated and hydrophobic PCHMA having a solubility parameter similar to that of THF. In the early stages of evaporation, the binary mixtures tend to induce the aggregation of PCH-NP due to the azeotropic point of the solvent components, leading to the formation of surface structures ranging from smooth to rough on the substrate. By adjusting the initial ratio of the binary solvents, a superhydrophobic coating with a water contact angle of 154 ± 2° and a sliding angle of less than 10° was achieved at a THF content of 60 wt %. This facile approach using azeotropes successfully shows that changes in the solvent composition of the binary solvent system during evaporation can be used to prepare superhydrophobic coatings with well-controlled surface structures.
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The repeated evolution of herbicide resistance has been cited as an example of genetic parallelism, wherein separate species or genetic lineages utilize the same genetic solution in response to selection. However, most studies that investigate the genetic basis of herbicide resistance examine the potential for changes in the protein targeted by the herbicide rather than considering genome-wide changes. We used a population genomics screen and targeted exome re-sequencing to uncover the potential genetic basis of glyphosate resistance in the common morning glory, Ipomoea purpurea, and to determine if genetic parallelism underlies the repeated evolution of resistance across replicate resistant populations. We found no evidence for changes in 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), glyphosate's target protein, that were associated with resistance, and instead identified five genomic regions that showed evidence of selection. Within these regions, genes involved in herbicide detoxification-cytochrome P450s, ABC transporters, and glycosyltransferases-are enriched and exhibit signs of selective sweeps. One region under selection shows parallel changes across all assayed resistant populations whereas other regions exhibit signs of divergence. Thus, while it appears that the physiological mechanism of resistance in this species is likely the same among resistant populations, we find patterns of both similar and divergent selection across separate resistant populations at particular loci.
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Genoma de Planta/genética , Glicina/análogos & derivados , Herbicidas/farmacologia , Ipomoea/genética , Plantas Daninhas/genética , 3-Fosfoshikimato 1-Carboxiviniltransferase/antagonistas & inibidores , 3-Fosfoshikimato 1-Carboxiviniltransferase/genética , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Evolução Molecular , Exoma/genética , Glicina/farmacologia , Resistência a Herbicidas/genética , Ipomoea/efeitos dos fármacos , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/genética , Plantas Daninhas/efeitos dos fármacos , Sementes/efeitos dos fármacos , Sementes/genética , Seleção Genética , Análise de Sequência de DNA , GlifosatoRESUMO
Examining how the landscape may influence gene flow is at the forefront of understanding population differentiation and adaptation. Such understanding is crucial in light of ongoing environmental changes and the elevated risk of ecosystems alteration. In particular, knowledge of how humans may influence population structure is imperative to allow for informed decisions in management and conservation as well as to gain a better understanding of anthropogenic impacts on the interplay between gene flow, genetic drift, and selection. Here, we use genome-wide molecular markers to characterize the population genetic structure and connectivity of Ipomoea purpurea (Convolvulaceae), a noxious invasive weed. We, likewise, assess the interaction between natural and human-driven influences on genetic differentiation among populations. Our analyses find that human population density is an important predictor of pairwise population differentiation, suggesting that the agricultural and/or horticultural trade may be involved in maintaining some level of connectivity across distant agricultural fields. Climatic variation appears as an additional predictor of genetic connectivity in this species. We discuss the implications of these results and highlight future research needed to disentangle the mechanistic processes underlying population connectivity of weeds.
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Adaptação Fisiológica/genética , Ipomoea/genética , Plantas Daninhas/genética , Seleção Genética/genética , Agricultura , Ecossistema , Fluxo Gênico/genética , Deriva Genética , Variação Genética/genética , Genética Populacional , Humanos , Espécies Introduzidas , Densidade DemográficaRESUMO
Evolutionary biologists remain puzzled by the often dramatic variation of mating strategies within single species. Of particular interest is the extent to which environmental conditions shape patterns of variation of mating system components within mixed mating species, and how widespread anthropogenic manipulations may influence these associations. Here, we address this question in the common morning glory (Ipomoea purpurea) by combining a dataset of floral traits, estimates of the mating system, and relevant environmental factors compiled for 22 populations of this species distributed along a wide range of environments from the Southeastern and Midwestern United States. We identify a disparate set of environmental factors to influence population-level variation in selfing, inbreeding, and flower morphology. Although floral traits are primarily associated with climatic variation, the outcrossing rate and inbreeding coefficient are primarily influenced by the level of herbicide resistance. Furthermore, we find that populations with higher levels of herbicide resistance exhibit a stronger correlation between mating system-floral traits and mating system estimates (outcrossing rate and inbreeding coefficient). Altogether, these results demonstrate the dominant role that herbicide application plays in the determination of I. purpurea's mating system, and more generally uncover the complex and unforeseen evolutionary consequences of anthropogenic manipulations in natural systems.
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Flores/fisiologia , Ipomoea/fisiologia , Evolução Biológica , Flores/genética , Variação Genética/efeitos dos fármacos , Herbicidas/farmacologia , Endogamia , Ipomoea/efeitos dos fármacos , Ipomoea/genética , Reprodução/efeitos dos fármacosRESUMO
Human-mediated selection can strongly influence the evolutionary response of natural organisms within ecological timescales. But what traits allow for, or even facilitate, adaptation to the strong selection humans impose on natural systems? Using a combination of laboratory and greenhouse studies of 32 natural populations of the common agricultural weed, Ipomoea purpurea, we show that herbicide-resistant populations self-fertilise more than susceptible populations. We likewise show that anther-stigma distance, a floral trait associated with self-fertilisation in this species, exhibits a nonlinear relationship with resistance such that the most and least resistant populations exhibit lower anther-stigma separation compared to populations with moderate levels of resistance. Overall, our results extend the general finding that plant mating can be impacted by human-mediated agents of selection to that of the extreme selection of the agricultural system. This work highlights the influence of human-mediated selection on rapid responses of natural populations that can lead to unexpected long-term evolutionary consequences.
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Evolução Biológica , Resistência a Herbicidas , Ipomoea/fisiologia , Seleção Genética , Autofertilização , Flores/fisiologia , Glicina/análogos & derivados , Glicina/farmacologia , Herbicidas/farmacologia , Ipomoea/efeitos dos fármacos , Ipomoea/genética , Estados Unidos , GlifosatoRESUMO
PREMISE OF THE STUDY: Abiotic environmental factors are often considered to be important in the distribution and maintenance of variation in sexual systems in flowering plants. Associations between sexes and abiotic factors are well documented in dioecious systems, but much less is known about this relationship in other sexually polymorphic systems. Species that are highly variable in sexual expression and habitat distribution can provide insights into the role of abiotic factors in maintaining variation in sexual expression. METHODS: Focusing on a sexually polymorphic species, Geranium transversale, we measured sexual expression at both the flower and the plant level and examined vegetative and floral traits, pollen deposition, and reproductive success. We also tested for correlations between sexual expression and other traits and examined whether and how these traits covaried with abiotic environmental conditions. KEY RESULTS: We identified unique variation of sexual expression in G. transversale. There are four sexual morphs that display different combinations of the three flower types (pistillate, staminate, and perfect). Sexual morphs that are phenotypically more female (i.e., female and gynomonoecious morphs) are found in wetter and milder environments, and flower earlier than morphs that are more male (i.e., hermaphroditic and andromonoecious morphs). Additionally, floral organ size and reproductive success are influenced not only by the flower type but also by the sexual morph of the plant. CONCLUSIONS: Environmental conditions are likely to cause some of the variation in sexual expression found in G. transversale. Both genetic and ecological factors likely contribute to the maintenance of sexual variation in this species.
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Flores/anatomia & histologia , Geranium/fisiologia , Sementes/crescimento & desenvolvimento , Flores/fisiologia , Polinização , Reprodução/fisiologia , SoloRESUMO
Despite the negative economic and ecological impact of weeds, relatively little is known about the evolutionary mechanisms that influence their persistence in agricultural fields. Here, we use a resurrection approach to examine the potential for genotypic and phenotypic evolution in Ipomoea purpurea, an agricultural weed that is resistant to glyphosate, the most widely used herbicide in current-day agriculture. We found striking reductions in allelic diversity between cohorts sampled nine years apart (2003 vs. 2012), suggesting that populations of this species sampled from agricultural fields have experienced genetic bottleneck events that have led to lower neutral genetic diversity. Heterozygosity excess tests indicate that these bottlenecks may have occurred prior to 2003. A greenhouse assay of individuals sampled from the field as seed found that populations of this species, on average, exhibited modest increases in herbicide resistance over time. However, populations differed significantly between sampling years for resistance: some populations maintained high resistance between the sampling years whereas others exhibited increased or decreased resistance. Our results show that populations of this noxious weed, capable of adapting to strong selection imparted by herbicide application, may lose genetic variation as a result of this or other environmental factors. We probably uncovered only modest increases in resistance on average between sampling cohorts due to a strong and previously identified fitness cost of resistance in this species, along with the potential that nonresistant migrants germinate from the seed bank.
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Evolução Molecular , Genética Populacional , Resistência a Herbicidas/genética , Ipomoea/genética , Plantas Daninhas/genética , Agricultura , Produtos Agrícolas , Variação Genética , North Carolina , South Carolina , TennesseeRESUMO
PREMISE OF THE STUDY: Pollen size varies greatly among flowering plant species and has been shown to influence the delivery of sperm cells to the eggs. Relatively little is known, however, about the functional significance of within-species genetic variation in pollen size. This study tests whether pollen size influences the relative siring success of a pollen donor during in vivo pollen competition experiments. METHODS: We used two groups of Ipomoea purpurea plants genetically divergent in their pollen sizes and applied equal number of pollen grains from one large-pollen and one small-pollen donor onto the same stigma. Using microsatellite genetic markers, we identified the pollen parent of each of the resulting progeny to determine the relative siring success of the competing donors. Competitions between donors of equal-sized pollen served as a control. KEY RESULTS: Differences in pollen size significantly affected the relative siring success of a pollen donor; larger-grained individuals outcompeted smaller-grained competitors but not equal-sized competitors. Relative siring success, however, sometimes varied across different pollen recipients. CONCLUSIONS: Pollen size can influence the relative siring success of different individuals competing on the same stigma during postpollination processes. However, other factors, such as pollen-pistil interaction and environmental conditions, are likely to influence these competitions as well.
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Organismos Hermafroditas , Ipomoea/anatomia & histologia , Ipomoea/fisiologia , Pólen/anatomia & histologia , Pólen/fisiologia , Polinização , Tamanho do Órgão , Característica Quantitativa HerdávelRESUMO
BACKGROUND AND AIMS: Gynodioecy, the co-occurrence of female and hermaphroditic individuals, is thought to be an intermediate step between hermaphroditism and separate sexes, a major transition in flowering plants. Because retaining females in a population requires that they have increased seed fitness (to compensate for the lack of pollen fitness), factors that affect seed fitness are of great importance to the evolution of this mating system and have often been studied. However, factors negatively affecting female fitness are equally important and have been largely neglected. One such factor stems from female flowers being less attractive to insects than hermaphrodite flowers, thereby decreasing their relative fitness. METHODS: To test the severity and consequences of this type of pollinator discrimination in Geranium maculatum, experimental populations with the range of sex ratios observed in nature were created, ranging from 13 % to 42 % females. Pollinators were observed in order to measure the strength of discrimination, and pollen deposition and seed production of both sexes were measured to determine the fitness consequences of this discrimination. Additionally a comparison was made across the sex ratios to determine whether discrimination was frequency-dependent. KEY RESULTS: It was found that female flowers, on average, were visited at half of the rate of hermaphrodite flowers, which decreased their pollen receipt and seed production. Additionally, females were most discriminated against when rare, due to both changes in the pollinators' behaviour and a shift in pollinator composition. CONCLUSIONS: The results suggest that pollinator discrimination negatively affects females' relative fitness when they are rare. Thus, the initial spread of females in a population, the first step in the evolution of gynodioecy, may be made more difficult due to pollinator discrimination.
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Abelhas/fisiologia , Geranium/fisiologia , Óvulo Vegetal/fisiologia , Polinização/fisiologia , Animais , Geranium/anatomia & histologia , Óvulo Vegetal/anatomia & histologia , Pólen/fisiologia , Reprodução , Razão de MasculinidadeRESUMO
BACKGROUND: The aim of this study was to determine the influence of inflammation on acute phase protein and epithelial-mesenchymal transition (EMT) in buccal cancer. METHODS: Western blotting was carried out to investigate the expression of haptoglobin and epithelial-mesenchymal transition in oral cancer cell lines with or without IL-6 stimulation. We studied patients with buccal cancer patients without distant metastasis at diagnosis. Correlation between cellular haptoglobin, EMT, and clinical characteristics of buccal cancer was analyzed to assess the prognostic value of cellular haptoglobin level and EMT. The relationship of haptoglobin, and EMT expression with survival was assessed using Cox proportional hazard models. RESULTS: Western blotting analysis showed that increased haptoglobin protein was associated with overexpression of vimentin. Under IL-6 stimulation, overexpression of haptoglobin, EMT-associated motile phenotype was noted in OC2 cell lines. Overexpression of haptoglobin was also associated with an increased risk for locoregional recurrence [hazard ratio (HR) 1.04; p=0.011] after adjusting for age, gender, disease site, stage, and treatment modality. CONCLUSIONS: Increased cellular expression of haptoglobin is associated with EMT in oral cancer cell lines and this phenomenon could be exaggerated with IL-6. Cellular expression of haptoglobin is related to locoregional recurrence rate in buccal cancer patients.
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Transição Epitelial-Mesenquimal , Haptoglobinas/biossíntese , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Movimento Celular , Bochecha/patologia , Feminino , Humanos , Imuno-Histoquímica , Interleucina-6/farmacologia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Vimentina/biossínteseRESUMO
Premise: Petal color is an ecologically important trait, and uncovering color variation over a geographic range, particularly in species with large distributions and/or short bloom times, requires extensive fieldwork. We have developed an alternative method that segments images from citizen science repositories using Python and k-means clustering in the hue-saturation-value (HSV) color space. Methods: Our method uses k-means clustering to aggregate like-color pixels in sample images to generate the HSV color space encapsulating the color range of petals. Using the HSV values, our method isolates photographs containing clusters in that range and bins them into a classification scheme based on user-defined categories. Results: We demonstrate the application of this method using two species: one with a continuous range of variation of pink-purple petals in Geranium maculatum, and one with a binary classification of white versus blue in Linanthus parryae. We demonstrate results that are repeatable and accurate. Discussion: This method provides a flexible, robust, and easily adjustable approach for the classification of color images from citizen science repositories. By using color to classify images, this pipeline sidesteps many of the issues encountered using more traditional computer vision applications. This approach provides a tool for making use of large citizen scientist data sets.
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Contemporary anthropogenic changes in climate and landscape form a complex set of selective pressures acting on natural systems, yet, in many systems, we lack information about both whether and how organisms may adapt to these changes. In plants, research has focused on climate-induced changes in phenology and the resultant potential for disruption of plant-pollinator interactions, however, there remains a paucity of knowledge regarding how other pollinator-mediated traits may be involved in the adaptive response. Here, we use resurrection experiments to investigate the phenotypic basis of adaptation in a mixed-mating system plant, the common morning glory (Ipomoea purpurea). Specifically, we measure temporal and spatial changes in traits grouped into three categories relevant to plant-pollinator interactions - floral morphology, floral rewards, and floral phenology. We show a significant temporal increase in corolla size and shift to earlier flowering times, as well as a potential for increased investment in floral rewards, all of which are driven primarily by populations at more northern latitudes. Additionally, we find evidence for directional selection on floral morphology and phenology and evidence of balancing selection acting on anther-stigma distance. Overall, these results show an adaptive response in line with greater investment in pollinator attraction rather than self-pollination and fine-scale spatial differences in adaptive potential.
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This study aimed to investigate the mechanical performance of early-strength carbon fiber-reinforced concrete (ECFRC) by incorporating original carbon fiber (OCF), recycled carbon fiber (RCF), and sizing-removed carbon fiber (SCF). Compressive, flexural, and splitting tensile strength were tested under three fiber-to-cement weight ratios (5‱, 10‱, and 15‱). The RCF was produced from waste bicycle parts made of carbon fiber-reinforced polymer (CFRP) through microwave-assisted pyrolysis (MAP). The sizing-removed fiber was obtained through a heat-treatment method applied to the OCF. The results of scanning electron microscopy (SEM) analysis with energy dispersive X-ray spectrometry (EDS) indicated the successful removal of sizing and impurities from the surface of the RCF and SCF. The mechanical test results showed that ECFRC with a 10‱ fiber-to-cement weight ratio of carbon fiber had the greatest improvement in its mechanical strengths. Moreover, the ECFRC with 10‱ RCF exhibited higher compressive, flexural, and splitting tensile strength than that of benchmark specimen by 14.2%, 56.5%, and 22.5%, respectively. The ECFRC specimens with a 10‱ fiber-to-cement weight ratio were used to analyze their impact resistance under various impact energies in the impact test. At 50 joules of impact energy, the impact number of the ECFRC with SCF was over 23 times that of the benchmark specimen (early-strength concrete without fiber) and was also greater than that of ECFRC with OCF and RCF.
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To improve the arachidonic acid (ARA) accumulation in Mortierella alpina, a mixed B-group vitamin addition strategy was developed. The ARA titer reached up to 10.0 g/L, 1.7-fold of the control. At the same time, the highest specific activities of key enzymes involved in ARA biosynthesis, including malic enzyme, glucose-6-phosphate dehydrogenase and ATP: citrate lyase, were 63.3, 38.6 and 53.7% higher than the control, respectively. The possible vitamin triggered improved ARA accumulation mechanism was thus elucidated that B-group vitamins could function as the cofactors of the key enzymes involved in ARA biosynthesis, or precursors for the formation of NADPH and acetyl-CoA which were crucial for ARA synthesis, and strengthened the related metabolic flux.
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Ácido Araquidônico/biossíntese , Mortierella/metabolismo , Complexo Vitamínico B/farmacologia , Trifosfato de Adenosina/biossíntese , Proteínas Fúngicas/biossíntese , Glucosefosfato Desidrogenase/biossíntese , Complexos Multienzimáticos/biossíntese , Oxo-Ácido-Liases/biossínteseRESUMO
Protein microarray chips are composed of three components, these are pre-treatment substrates, surface chemical modification, and immobilizing protein on substrate surfaces. In this study, self-assembly monolayers are used for surface chemical modification. Using this method, silanization on a glass and silicon chip is achieved, forming the terminal group substrates. Modification of the substrate surface to provide COOH and NH2 terminal functional groups provides a mechanism to proteins to immobilize on the substrate surface. To observe immobilized proteins on the substrate surface, they are first labeled with Cy5 fluorescent dye before analysis using a GenePix 4000B Microarray Scanner. The scanner induces fluorescence in the labelling dye and the resulting light is analyzed to provide information concerning both the quantity of immobilized protein, and the orientation of attachment. The antigen of the HSV-1 virus, a common human virus, was used in this study, performing an antigen-antibody analysis to determine the efficacy of the method under test for clinical diagnosis.
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Análise Serial de Proteínas , Proteínas , Antígenos , Corantes Fluorescentes , Humanos , Análise Serial de Proteínas/métodos , Silício , Propriedades de SuperfícieRESUMO
Spinel structured aluminates TAl2O4 (T = Mg, Zn, and Cu) were synthesized by a facile hydrothermal method. The resultant enhancement in the electrochemical behavior was achieved due to the covalent synergism among the elements coexisting together. Structural and morphological characterizations were performed by X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, and field emission scanning electron microscopy. MgAl2O4, ZnAl2O4 and CuAl2O4 has displayed same space group Fd3m of Laue class lattice type of the cubic structure as they were synthesized at same temperature (600 °C). CuAl2O4 spinel structure displayed a nanoneedle like structure along with the small sized cylindrical particles alongside to which CuAl2O4 spinel is combined with activated carbon (CuAl/C) and was applied to develop a facile sensor for the electrochemical detection of Acetaminophen (ACAP) using cyclic voltammetry (CV) and differential pulse voltammetry (DPV), which exhibited maximum conductivity, and a substantial electroactive surface area. Finally, the defect-rich composite, CuAl/C, showed excellent sensor performance towards DPV with 21.5 nM limit of detection (LOD) in a wide linear working range of 0.199 µM-165.88 µM ACAP concentration, with a high sensitivity of 19.1221 µA µM-1cm2. Additionally, the sensor showed excellent recovery results in real-time analysis for environmental aquatic samples like industrial wastewater and Tuna Fish.
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Óxido de Alumínio , Técnicas Eletroquímicas , Animais , Técnicas Eletroquímicas/métodos , Eletrodos , Óxido de Magnésio , ZincoRESUMO
Medication nonadherence is associated with an increased risk of complications in hypertensive patients. We investigated behavioral factors associated with medication nonadherence in hypertensive patients in southern Taiwan. Using questionnaires, we collected data regarding clinicodemographic characteristics and nonadherence behaviors from 238 hypertensive patients. We assessed the self-reported prevalence of specific behaviors of medication nonadherence and investigated factors associated with each behavior using multivariable logistic regression analysis. The most common behavior of medication nonadherence was forgetting to take medication (28.6%), followed by discontinuing medication (9.2%) and reducing the medication dose (8.8%). Age ≥ 65 years (adjusted odds ratio [aOR] = 0.32, 95% confidence interval [CI] = 0.15-0.69) and male sex (aOR = 2.61, CI = 1.31-5.19) were associated with forgetting to take medication. The presence of comorbidities (diabetes, kidney disease, or both) and insomnia (aOR = 3.97, 95% CI = 1.30-12.1) was associated with reducing the medication dose. The use of diet supplements was associated with discontinuing the medication (aOR = 4.82, 95% CI = 1.50-15.5). Compliance with a low oil/sugar/sodium diet was a protective factor against discontinuing medication (aOR = 0.14; 95% CI = 0.03-0.75). The most pervasive behavior associated with medication nonadherence among hypertensive patients was forgetting to take medication. Age <65 years, male sex, comorbidities, insomnia, noncompliance with diet, and the use of dietary supplements were specifically associated with medication nonadherence.
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Hipertensão , Adesão à Medicação , Idoso , Comorbidade , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Masculino , Razão de Chances , AutorrelatoRESUMO
The rapid development of metal nanoparticles capped by an organic monolayer offers the possibility to create a whole new variety of products with novel characteristic, functions and applications. Among these, nanoparticles covered with carbohydrates (glyconanoparticles) constitute a good bio-mimetic model of carbohydrate presentation at the cell surface and are currently centered on many glycobiological and biomedical applications. In this study, a series of novel D-xylose gold nanoparticles (AuNPs) with linkages of alkyl or polyethylene glycol have been synthesized via D-xylosethiols, forming self-assembled monolayers on gold nanoparticles. The nano-gold solution, two carbohydrate derivatives and modified nano-gold solution were tested for cytotoxicity to check the biocompatibility. The MTT assay on NIH 3T3 cell lines confirmed that all the test materials showed no toxicity with the more than 90 % of cell viability in both low concentration (1 µM) and high concentration (100 µM), compared with the control.
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Populations containing both females and hermaphrodites (dimorphic) are generally found in drier sites than those with only hermaphrodites (monomorphic). The sex-differential plasticity hypothesis (SDP) suggests that this is caused by hermaphrodites reducing allocation to seeds in harsh environments, allowing female establishment. We proposed that a similar process could explain sex distribution within populations. We compared light availability and soil moisture between sites of three monomorphic and three dimorphic populations of Geranium maculatum and between microsites occupied by females and hermaphrodites within populations. We also correlated seed production in dimorphic populations with environmental measures. We found that dimorphic and monomorphic populations occurred in sites with similar soil moisture but within two dimorphic populations females occurred in drier microsites than hermaphrodites, as predicted by the SDP hypothesis. Contrary to the predictions, hermaphrodites' seed production was not influenced by the environment. Rather, females' seed production was correlated with environmental conditions in two populations, although the direction of the correlation differed between populations. Our results suggest that in this species, the SDP hypothesis does not explain sex distribution among or within populations. However, microsite environments may influence the distribution of sexes within a population and potentially aid in maintaining gynodioecy.
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Meio Ambiente , Geranium/fisiologia , Caracteres Sexuais , Flores/fisiologia , Luz , Modelos Biológicos , Dinâmica Populacional , Análise de Regressão , Estações do Ano , Sementes/crescimento & desenvolvimento , SoloRESUMO
Granular cell tumor (GCT) of the thyroid is rare. Before this report, only four cases of thyroid GCT have been reported, none of which presented a cytopathological examination. In this paper, we report the fine needle aspiration cytology and pathological analysis of a thyroid GCT from a 12-year-old girl who presented with a painless neck mass. The tumor cells were single, in syncytial clusters, or pseudofollicles, contained small round, oval, or spindle nuclei, indistinct nucleoli, and a large amount of grayish, granular fragile cytoplasm. The background contained granular debris and naked nuclei. A differential diagnosis of thyroid GCT with more frequent thyroid lesions containing cytoplasmic granules, including Hurthle cells, macrophages, follicular cells, and cells of black thyroid syndrome, was also performed.