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2.
PLoS One ; 15(7): e0234648, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645027

RESUMO

Adaptation of weeds to water stress could result in the broader distribution, and make weed control task increasingly difficult. Therefore, a clear understanding of the biology of weeds under water stress could assist in the development of sustainable weed management strategies. Avena fatua (wild oat) and A. ludoviciana (sterile oat) are problematic weeds in Australian winter crops. The objectives of this study were to determine the growth and reproductive behaviour of A. fatua and A. ludoviciana at different soil moisture levels [20, 40, 60, 80, and 100% water holding capacity (WHC)]. Results revealed that A. fatua did not survive and failed to produce seeds at 20 and 40% WHC. However, A. ludoviciana survived at 40% WHC and produced 54 seeds plant-1. A. fatua produced a higher number of seeds per plant than A. ludoviciana at 80 (474 vs 406 seeds plant-1) and 100% WHC (480 vs 417 seeds plant-1). Seed production for both species remained similar at 80 and 100% WHC; however, higher than 60% WHC. Seed production of A. fatua and A. ludoviciana was 235 and 282 seeds plant-1, respectively, at 60% WHC. The 60% WHC reduced seed production of A. fatua and A. ludoviciana by 51 and 32% respectively, compared to 100% WHC. The plant height, leaf weight, stem weight, and root weight per plant of A. fatua at 60% WHC reduced by 45, 27, 32, and 59%, respectively, as compared with 100% WHC. Similarly, the plant height, leaf weight, stem weight, and root weight per plant of A. ludoviciana at 60% WHC reduced by 45, 35, 47 and 76%, respectively, as compared with 100% WHC. Results indicate that A. ludoviciana can survive and produce seeds at 40% of WHC, indicating the adaptation of the species to dryland conditions. The results also suggest that A. ludoviciana is likely to be robust under water stress conditions, potentially reducing crop yield. The ability of A. fatua and A. ludoviciana to produce seeds under water-stressed conditions (60% WHC) necessitates integrated weed management strategies that suppress these weeds whilst taking into account the efficient utilization of stored moisture for winter crops.


Assuntos
Avena/crescimento & desenvolvimento , Solo/química , Controle de Plantas Daninhas/métodos , Austrália , Fenômenos Biológicos , Produtos Agrícolas/crescimento & desenvolvimento , Desidratação/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Plantas Daninhas/crescimento & desenvolvimento , Água/metabolismo
3.
Acta Crystallogr C Struct Chem ; 76(Pt 7): 673-680, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32624514

RESUMO

Four new picolinohydrazonamide derivatives, namely, 6-methyl-N'-(morpholine-4-carbonothioyl)picolinohydrazonamide, C12H17N5OS, 6-chloro-N'-(morpholine-4-carbonothioyl)picolinohydrazonamide methanol monosolvate, C11H14ClN5OS·CH3OH, 6-chloro-N'-(4-phenylpiperazine-1-carbonothioyl)picolinohydrazonamide, C17H19ClN6S, and 6-chloropicolinohydrazonamide, C6H7ClN4, have been synthesized and characterized by NMR spectroscopy and single-crystal low-temperature X-ray diffraction. In addition, their antibacterial and anti-yeast activities have been determined. The first three compounds adopt the zwitterionic form in the crystal structure regardless of the presence or absence of solvent molecules in the structure. They also adopt the same symmetry, i.e. P21/c (P21/n), unlike the fourth structure which is chiral and has the space group P212121. For all the studied cases, intermolecular N-H...O and N-H...N hydrogen bonds play an essential role in the formation of the structures.


Assuntos
Antibacterianos/farmacologia , Morfolinas/química , Antibacterianos/química , Fenômenos Biológicos , Cristalografia por Raios X , Ligação de Hidrogênio , Estrutura Molecular , Solventes/química
4.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(3): 324-329, 2020 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-32573143

RESUMO

Lysophosphatidic acid (LPA) is a small phospholipid that is present in all eukaryotic tissues and blood plasma. As an extracellular signaling molecule, LPA mediates many cellular functions by binding to six known G protein-coupled receptors and activating their downstream signaling pathways. These functions indicate that LPA may play important roles in many biological processes that include organismal development, wound healing, and carcinogenesis. Recently, many studies have found that LPA has various biological effects in different kinds of bone cells. These findings suggest that LPA is a potent regulator of bone development and remodeling and holds promising application potential in bone tissue engineering. Here, we review the recent progress on the biological regulatory function of LPA in bone tissue cells.


Assuntos
Fenômenos Biológicos , Receptores de Ácidos Lisofosfatídicos , Osso e Ossos , Lisofosfolipídeos
5.
Proc Natl Acad Sci U S A ; 117(27): 15748-15754, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571943

RESUMO

Trade-offs between growth, reproduction, and lifespan constrain animal life histories, leading to evolutionary diversification of life history cycles in different environments. In female mammals, gestation and lactation are expected to impose the major costs of reproduction, driving reproductive trade-offs, although mating also requires interactions with males that could themselves influence life history. Here we show that a male's presence by itself leads to lifelong alterations in life history in female mice. Housing C57BL/6J female mice with sterilized males early in life led to an increase in body weight, an effect that persisted across life even when females were later allowed to produce pups. We found that those females previously housed with sterile males also showed enhanced late-life offspring production when allowed to reproduce, indicating that earlier mating can influence subsequent fecundity. This effect was the opposite to that seen in females previously housed with intact males, which showed the expected trade-off between early-life and late-life reproduction. However, housing with a sterile male early in life came at a cost to lifespan, which was observed in the absence of females ever undergoing fertilization. Endocrinologically, mating also permanently reduced the concentration of circulating prolactin, a pituitary hormone influencing maternal care. Changes in hormone axes that influence reproduction could therefore help alter life history allocation in response to opposite-sex stimuli. Our results demonstrate that mating itself can increase growth and subsequent fecundity in mammals, and that responses to sexual stimuli could account for some lifespan trade-offs normally attributed to pregnancy and lactation.


Assuntos
Evolução Biológica , Fertilidade/fisiologia , Longevidade/fisiologia , Reprodução/fisiologia , Animais , Fenômenos Biológicos , Peso Corporal/genética , Peso Corporal/fisiologia , Comunicação Celular , Feminino , Fertilidade/genética , Infertilidade Masculina/genética , Lactação , Longevidade/genética , Masculino , Camundongos , Reprodução/genética , Comportamento Sexual Animal/fisiologia
6.
Environ Pollut ; 264: 114707, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32388307

RESUMO

Exposure to long-term ambient air pollution is believed to have adverse effects on human health. However, the mechanisms underlying these impacts are poorly understood. DNA methylation, a crucial epigenetic modification, is susceptible to environmental factors and likely involved in these processes. We conducted a whole-genome bisulfite sequencing study on 120 participants from a highly polluted region (HPR) and a less polluted region (LPR) in China, where the HPR had much higher concentrations of five air pollutants (PM2.5, PM10, SO2, NO2, and CO) (fold difference 1.6 to 6.6 times; P value 1.80E-07 to 3.19E-23). Genome-wide methylation analysis revealed 371 DMRs in subjects from the two areas and these DMRs were located primarily in gene regulatory elements such as promoters and enhancers. Gene enrichment analysis showed that DMR-related genes were significantly enriched in diseases related to pulmonary disorders and cancers and in biological processes related to mitochondrial assembly and cytokine production. Further, HPR participants showed a higher mtDNA copy number. Of those identified DMRs, 15 were significantly correlated with mtDNA copy number. Finally, cytokine assay indicated that an increased plasma interleukin-5 level was associated with greater air pollution. Taken together, our findings suggest that exposure to long-term ambient air pollution can lead to alterations in DNA methylation whose functions relate to mitochondria and immune responses.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Fenômenos Biológicos , China , Metilação de DNA , Exposição Ambiental/análise , Humanos , Mitocôndrias , Material Particulado/análise
7.
Sci Total Environ ; 731: 138386, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32417469

RESUMO

Vibrio parahaemolyticus is a kind of gram-negative marine pathogen, which usually adheres to stainless steel (SS), glass (GS) and other abiotic surfaces in aquaculture and food processing in the form of biofilm and causes the spread of gastrointestinal illness. However, the deeply survival adaptation mechanism of V. parahaemolyticus biofilm cells on these contact surface remained unclear. Here, proteomics was used to investigated the physiological response of the V. parahaemolyticus biofilms cells to different abiotic surfaces (SS, GS and polystyrene (PS)). In addition, the effect of contact materials on the physical-chemical properties of biofilms are also characterized. Results showed that the expression of proteins of biofilm cells established on the SS surface were mainly related to the alleviation of metal ion stress and toxicity. The up-regulated proteins in the biofilm cells formed on the GS surface were mainly involved in the biological processes of sugar uptake, protein synthesis and bacterial chemotaxis. Meanwhile, the significantly expressed proteins in the biofilm cells formed on the PS surface were mainly involved in the cellular physiological activity of aromatic compound metabolism, osmotic stress and nutrient transport. All functional proteins mentioned above were closely related to the interaction characteristics of the contact surface and biofilm. This study provided an in-depth comparison of V. parahaemolyticus biofilm formation on these three abiotic surfaces, and presented a model in first time for the adaptation behavior of biofilm cells on different surfaces as affected by metal ion stress, nutrition, osmotic stress, and sugar utilization, which could facilitate an efficient control strategy for biofilm formation in industrial field.


Assuntos
Fenômenos Biológicos , Vibrio parahaemolyticus , Biofilmes , Proteômica , Aço Inoxidável
8.
Bioresour Technol ; 311: 123568, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32467028

RESUMO

This review presents an emerging biorefinery platform for C2-5 bioalcohol production through chemical synthesis using the organic waste materials. Bioalcohols are the most commercialized carbon-neutral transportation fuels, compatible with existing an internal combustion (IC) engine. However, current bioalcohol fermentation processes have made from sugar-rich edible crops. Also, carbon loss from the fermentation process is substantial. To minimize carbon loss, volatile fatty acids (VFAs) can be utilized as a raw material for bioalcohol production. Thus, a two-step chemical upgrading of VFAs into C2-5 alcohols is summarized in comparison with current challenges of biological fermentation processes for bioalcohol production. This review also provides the prospect of the hybrid biological/chemical process, presenting the technical advantages of the system. Finally, economic viability of hybridized process for bioalcohol production is compared with the current biological process.


Assuntos
Fenômenos Biológicos , Ácidos Graxos Voláteis , Reatores Biológicos , Carboidratos , Fermentação , Esgotos , Resíduos
10.
Environ Pollut ; 263(Pt B): 114443, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32311622

RESUMO

We previously found bisphenol A (BPA) alternative, bisphenol F (BPF) upregulated Notch-related gene expression in intestines of the African clawed frog Xenopus laevis, suggesting an agonistic action on Notch signaling, a crucial signaling in multiple biological processes during development. Here, we aimed to confirm the actions of BPA and BPF on Notch signaling and to reveal their effects on intestinal development. Using X. laevis, an excellent model for developmental biology, we found that 10-1000 nM BPA and BPF significantly elevated Notch-related gene expression in a concentration-dependent manner. Subsequently, exceptional cell proliferation as well as intestinal histological changes were observed in treated intestines. Importantly, Notch inhibitor markedly suppressed the effects of BPA and BPF described above. Furthermore, we employed rat intestinal epithelium cells (IEC-6), an ideal in vitro model of intestinal epithelial cell differentiation, to confirm the effects of bisphenols. As expected, BPA and BPF upregulated Notch-related gene expression and induced the translocation of the Notch intracellular domain to the nucleus, followed by exceptional cell proliferation and differentiation, whereas Notch inhibitor antagonized the effects caused by BPA and BPF. All results strongly demonstrate that both BPA and BPF activate Notch signaling and subsequently disrupt intestinal development in vertebrates. Given its fundamental roles in multiple developmental processes, we propose that Notch signaling is an important and general target signaling of bisphenols in many developing tissues of vertebrates including humans.


Assuntos
Compostos Benzidrílicos , Fenômenos Biológicos , Animais , Humanos , Intestinos , Fenóis , Ratos
11.
PLoS One ; 15(4): e0230944, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267857

RESUMO

A new species of encyrtid wasp, Metaphycus macadamiae Polaszek & Noyes sp. n., (Hymenoptera: Encyrtidae: Encyrtinae) is described as a solitary endoparasitoid of the invasive macadamia felted coccid, Acanthococcus ironsidei (Hemiptera: Eriococcidae) in Hawaii. This parasitoid is native to Australia, and the species description is based on material collected from a Macadamia integrifolia Maiden & Betche (Proteaceae) plantation in New South Wales, Australia, the native region of the host tree and insect. It is described here because it is a potential biological control agent against this pest where it has recently invaded Hawaii and South Africa.


Assuntos
Hemípteros/efeitos dos fármacos , Macadamia/química , Animais , Austrália , Fenômenos Biológicos/efeitos dos fármacos , Hawaii , Himenópteros/efeitos dos fármacos , New South Wales , Controle Biológico de Vetores/métodos , África do Sul , Vespas/efeitos dos fármacos
12.
Nat Commun ; 11(1): 1493, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32198352

RESUMO

Quantifying the extent to which points are clustered in single-molecule localization microscopy data is vital to understanding the spatial relationships between molecules in the underlying sample. Many existing computational approaches are limited in their ability to process large-scale data sets, to deal effectively with sample heterogeneity, or require subjective user-defined analysis parameters. Here, we develop a supervised machine-learning approach to cluster analysis which is fast and accurate. Trained on a variety of simulated clustered data, the neural network can classify millions of points from a typical single-molecule localization microscopy data set, with the potential to include additional classifiers to describe different subtypes of clusters. The output can be further refined for the measurement of cluster area, shape, and point-density. We demonstrate this approach on simulated data and experimental data of the kinase Csk and the adaptor PAG in primary human T cell immunological synapses.


Assuntos
Fenômenos Biológicos , Análise por Conglomerados , Aprendizado de Máquina , Microscopia/métodos , Humanos , Redes Neurais de Computação , Imagem Óptica/métodos , Imagem Individual de Molécula , Software , Fluxo de Trabalho
13.
PLoS One ; 15(3): e0230218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32191739

RESUMO

Water is essential for living organisms. Terrestrial organisms are incessantly exposed to the stress of losing water, desiccation stress. Avoiding the mortality caused by desiccation stress, many organisms acquired molecular mechanisms to tolerate desiccation. Larvae of the African midge, Polypedilum vanderplanki, and its embryonic cell line Pv11 tolerate desiccation stress by entering an ametabolic state, anhydrobiosis, and return to active life after rehydration. The genes related to desiccation tolerance have been comprehensively analyzed, but transcriptional regulatory mechanisms to induce these genes after desiccation or rehydration remain unclear. Here, we comprehensively analyzed the gene regulatory network in Pv11 cells and compared it with that of Drosophila melanogaster, a desiccation sensitive species. We demonstrated that nuclear transcription factor Y subunit gamma-like, which is important for drought stress tolerance in plants, and its transcriptional regulation of downstream positive feedback loops have a pivotal role in regulating various anhydrobiosis-related genes. This study provides an initial insight into the systemic mechanism of desiccation tolerance.


Assuntos
Proteínas de Insetos/genética , Fatores de Transcrição/genética , Animais , Fenômenos Biológicos/genética , Linhagem Celular , Chironomidae/genética , Desidratação/genética , Dessecação/métodos , Drosophila melanogaster/genética , Regulação da Expressão Gênica/genética , Larva/genética , Estresse Fisiológico/genética
14.
Chemistry ; 26(33): 7479-7485, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32181923

RESUMO

Specific molecular recognition of γ-cyclodextrin (γ-CD) by the cationic hexanuclear niobium [Nb6 Cl12 (H2 O)6 ]2+ cluster complex in aqueous solutions results in a 1:1 supramolecular assembly {[Nb6 Cl12 (H2 O)6 ]@γ-CD}2+ . NMR spectroscopy, isothermal titration calorimetry (ITC), and ESI-MS were used to study the interaction between the inorganic cluster and the organic macrocycle. Such molecular association affects the biological activity of [Nb6 Cl12 (H2 O)6 ]2+ , decreasing its cytotoxicity despite enhanced cellular uptake. The 1:1 stoichiometry is maintained in solution over a large window of the reagents' ratio, but crystallization by slow evaporation produces a 1:2 host-guest complex [Nb6 Cl12 (H2 O)6 @(γ-CD)2 ]Cl2 ⋅20 H2 O featuring the cluster encapsulated between two molecules of γ-CD. The 1:2 complex was characterized by XRD, elemental analysis, IR spectroscopy, and thermogravimetric analysis (TGA). Quantum chemical calculations were performed to model host-guest interaction.


Assuntos
Nióbio/química , gama-Ciclodextrinas/química , Fenômenos Biológicos , Calorimetria , Espectroscopia de Ressonância Magnética , Água/química
15.
PLoS Comput Biol ; 16(2): e1007652, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32069277

RESUMO

English Wikipedia, containing more than five millions articles, has approximately eleven thousands web pages devoted to proteins or genes most of which were generated by the Gene Wiki project. These pages contain information about interactions between proteins and their functional relationships. At the same time, they are interconnected with other Wikipedia pages describing biological functions, diseases, drugs and other topics curated by independent, not coordinated collective efforts. Therefore, Wikipedia contains a directed network of protein functional relations or physical interactions embedded into the global network of the encyclopedia terms, which defines hidden (indirect) functional proximity between proteins. We applied the recently developed reduced Google Matrix (REGOMAX) algorithm in order to extract the network of hidden functional connections between proteins in Wikipedia. In this network we discovered tight communities which reflect areas of interest in molecular biology or medicine and can be considered as definitions of biological functions shaped by collective intelligence. Moreover, by comparing two snapshots of Wikipedia graph (from years 2013 and 2017), we studied the evolution of the network of direct and hidden protein connections. We concluded that the hidden connections are more dynamic compared to the direct ones and that the size of the hidden interaction communities grows with time. We recapitulate the results of Wikipedia protein community analysis and annotation in the form of an interactive online map, which can serve as a portal to the Gene Wiki project.


Assuntos
Fenômenos Biológicos , Biologia Computacional/métodos , Mapeamento de Interação de Proteínas , Proteínas/química , Ferramenta de Busca , Algoritmos , Análise por Conglomerados , Bases de Dados Genéticas , Internet , Cadeias de Markov , Probabilidade
16.
Chemistry ; 26(26): 5770-5773, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32027764

RESUMO

X-ray structures of homopolymeric human L-ferritin and horse spleen ferritin were solved by freezing protein crystals at different time intervals after exposure to a ferric salt and revealed the growth of an octa-nuclear iron cluster on the inner surface of the protein cage with a key role played by some glutamate residues. An atomic resolution view of how the cluster formation develops starting from a (µ3 -oxo)tris[(µ2 -glutamato-κO:κO')](glutamato-κO)(diaquo)triiron(III) seed is provided. The results support the idea that iron biomineralization in ferritin is a process initiating at the level of the protein surface, capable of contributing coordination bonds and electrostatic guidance.


Assuntos
Apoferritinas/química , Ferritinas/química , Ferro/química , Animais , Apoferritinas/metabolismo , Fenômenos Biológicos , Cavalos , Humanos
17.
Sci Total Environ ; 704: 135271, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31791783

RESUMO

Warming and eutrophication can have varying effects on exotic species performance and their interactions. These effects can vary with trophic level, but are rarely investigated simultaneously on exotic species from multiple trophic levels. To address this, we manipulated temperature, nutrients, and plant origin (native vs. exotic) in snail invaded wetland communities. Warming increased exotic apple snail (Pomacea maculata) reproduction (4-fold increase in egg mass) and also number of egg clutches produced while warming slowed exotic snail growth, suggesting a trade-off between reproduction and growth in exotic snails influenced by warming and nutrients. However, exotic snail size varied with warming and nutrients. Additionally, warming reduced native plant mass with no effect on exotic plants while nutrients had greater positive effects on exotic plants biomass. In combination warming and nutrient enrichment will likely increase exotic snail growth, while nutrient enrichment alone will contribute to exotic plant dominance. In conclusion, the individual and interactive effects of warming and eutrophication vary with the trophic level of exotic species with trade-offs in exotic herbivores depending on environmental conditions, making it difficult to predict effects of multiple anthropogenic factors on co-occurring exotic plants and their effects on native communities.


Assuntos
Espécies Introduzidas , Caramujos , Áreas Alagadas , Animais , Fenômenos Biológicos , Biomassa , Eutrofização , Alimentos , Herbivoria , Plantas , Reprodução
18.
Bioresour Technol ; 297: 122416, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31786035

RESUMO

Wastes containing critical metals are generated in various fields, such as energy and computer manufacturing. Metal-bearing wastes are considered as secondary sources of critical metals. The conventional physicochemical methods of metals recovery are energy-intensive and cause further pollution. Low-cost and eco-friendly technologies including biosorbents, bioelectrochemical systems (BESs), bioleaching, and biomineralization, have become alternatives in the recovery of critical metals. However, a relatively low recovery rate and selectivity severely hinder their large-scale applications. Researchers have expanded their focus to exploit novel strain resources and strategies to improve the biorecovery efficiency. The mechanisms and potential applicability of modified biological techniques for improving the recovery of critical metals need more attention. Hence, this review summarize and compare the strategies that have been developed for critical metals recovery, and provides useful insights for energy-efficient recovery of critical metals in future industrial applications.


Assuntos
Fenômenos Biológicos , Metais
19.
Sci Total Environ ; 702: 134993, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31726336

RESUMO

Since the establishment of the whole-contact sediment toxicity test using Heterocypris incongruens in 2012, this user-friendly method has been widely used for the assessment of many kinds of solid samples, such as sediment, soil, compost, and sewage sludge. There are two endpoints for this method: mortality and growth inhibition. Currently, there is no standard toxicity threshold established for the endpoint of growth inhibition. However, there is evidence showing that the calcite saturation state of the overlying water, which might be different among various samples, influences the growth and survival of H. incongruens. Thus, it is necessary to characterize the influence of the calcite saturation state to ensure that the test results are reliable and comparable among different samples. In the present study, we created artificial sediments comprised of quartz sand and 0-20% calcite particulates to manipulate the calcite saturation state in the overlying water and performed the test using H. incongruens for 6 d. The results show that a low calcite saturation state inhibited the growth of H. incongruens but had no effect on survival rate. The growth of ostracods was linearly related to the calcite saturation index of the overlying water. Additionally, a formula for artificial sediment consisting of 10% calcite and 90% quartz sand for the H. incongruens toxicity test was proposed. This study helps to distinguish H. incongruens growth inhibition caused by calcite saturation from that caused by toxicity.


Assuntos
Carbonato de Cálcio/química , Crustáceos/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Fenômenos Biológicos , Sedimentos Geológicos/química , Esgotos , Solo , Testes de Toxicidade , Poluentes Químicos da Água/normas
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