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1.
Ecol Evol ; 14(2): e10973, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38343568

RESUMO

Polyphagous insect herbivores feed on multiple host-plant species and face a highly variable chemical landscape. Comparative studies of polyphagous herbivore metabolism across a range of plants is an ideal approach for exploring how intra- and interspecific chemical variation shapes species interactions. We used polyphagous caterpillars of Lymantria mathura (Erebidae, Lepidoptera) to explore mechanisms that may contribute to its ability to feed on various hosts. We focused on intraspecific variation in polyphenol metabolism, the fates of individual polyphenols, and the role of previous feeding experience on polyphenol metabolism and leaf consumption. We collected the caterpillars from Acer amoenum (Sapindaceae), Carpinus cordata (Betulaceae), and Quercus crispula (Fagaceae). We first fed the larvae with the leaves of their original host and characterized the polyphenol profiles in leaves and frass. We then transferred a subset of larvae to a different host species and quantified how host shifting affected their leaf consumption and polyphenol metabolism. There was high intraspecific variation in frass composition, even among caterpillars fed with one host. While polyphenols had various fates when ingested by the caterpillars, most of them were passively excreted. When we transferred the caterpillars to a new host, their previous experience influenced how they metabolized polyphenols. The one-host larvae metabolized a larger quantity of ingested polyphenols than two-host caterpillars. Some of these metabolites could have been sequestered, others were probably activated in the gut. One-host caterpillars retained more of the ingested leaf biomass than transferred caterpillars. The pronounced intraspecific variation in polyphenol metabolism, an ability to excrete ingested metabolites and potential dietary habituation are factors that may contribute to the ability of L. mathura to feed across multiple hosts. Further comparative studies can help identify if these mechanisms are related to differential host-choice and response to host-plant traits in specialist and generalist insect herbivores.

2.
Bioinspir Biomim ; 19(1)2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37939389

RESUMO

As one of the unique owl-wing morphologies, trailing-edge (TE) fringes are believed to play a critical role in the silent flight of owls and have been widely investigated using idealized single/tandem airfoils. However, the effect of TE fringes and associated mechanisms on the aeroacoustics of owl wings, which feature curved leading edges, wavy TEs, and several feather slots at the wingtips, have not yet been addressed. In this study, we constructed two 3D owl wing models, one with and one without TE fringes, based on the geometric characteristics of a real owl wing. Large-eddy simulations and the Ffowcs Williams‒Hawkings analogy were combined to resolve the aeroacoustic characteristics of the wing models. Comparisons of the computed aerodynamic forces and far-field acoustic pressure levels demonstrate that the fringes on owl wings can robustly suppress aerodynamic noise while sustaining aerodynamic performance comparable to that of a clean wing. By visualizing the near-field flow dynamics in terms of flow and vortex structures as well as flow fluctuations, the mechanisms of TE fringes in owl wing models are revealed. First, the TE fringes on owl wings are reconfirmed to robustly suppress flow fluctuations near the TE by breaking up large TE vortices. Second, the fringes are observed to effectively suppress the shedding of wingtip vortices by mitigating the flow interaction between feathers (feather-slot interaction). These complementary mechanisms synergize to enhance the robustness and effectiveness of the TE fringe effects in owl wing models, in terms of aerodynamic force production and noise suppression. This study thus deepens our understanding of the role of TE fringes in real owl flight gliding and points to the validity and feasibility of employing owl-inspired TE fringes in practical applications of low-noise fluid machinery.


Assuntos
Estrigiformes , Animais , Modelos Biológicos , Voo Animal , Asas de Animais , Plumas , Fenômenos Biomecânicos
3.
Plant Signal Behav ; 18(1): 2180159, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36800921

RESUMO

Partial mycoheterotrophic i.e., mixotrophic, plants are the species which partially depend on mycorrhizal fungi for its nutrients. Although some of these plants are known to show plasticity in the degree of fungal dependence induced by the changes in light condition, the genetic background of this plasticity is largely unsolved. Here, we investigated the relationships between environmental conditions and nutrient sources based on 13C and 15N enrichment in mixotrophic orchid Cymbidium goeringii. We also shaded them for 2 months and evaluated the effect of light condition on the nutrient sources based on the abundance of 13C and 15N and the gene expressions by RNA-seq based de novo assembly. The shading had no effect on isotope enrichment, possibly because of the translocation of carbon and nitrogen from the storage organs. Gene expression analysis showed the upregulation of genes involved in jasmonic acid response in leaves of the shaded plants, which suggests that the jasmonic acid played an important role in regulation of degree of dependence against the mycorrhizal fungi. Our results suggest that mixotrophic plants might be controlling their dependency against the mycorrhizal fungi by a common mechanism with the autotrophic plants.


Assuntos
Micorrizas , Orchidaceae , Simbiose/genética , Micorrizas/fisiologia , Ciclopentanos/metabolismo , Orchidaceae/microbiologia , Expressão Gênica
4.
Mol Ecol ; 31(11): 3083-3097, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35364616

RESUMO

Herbivorous insects have evolved counteradaptations to overcome the chemical defences of their host plants. Several of these counteradaptations have been elucidated at the molecular level, in particular for insects specialized on cruciferous host plants. While the importance of these counteradaptations for host plant colonization is well established, little is known about their microevolutionary dynamics in the field. In particular, it is not known whether and how host plant diversity shapes diversity in insect counteradaptations. In this study, we examine patterns of host plant use and insect counteradaptation in three Pieris butterfly species across Japan. The larvae of these butterflies express nitrile-specifier protein (NSP) and its paralogue major allergen (MA) in their gut to overcome the highly diversified glucosinolate-myrosinase defence system of their cruciferous host plants. Pieris napi and Pieris melete colonize wild Brassicaceae whereas Pieris rapae typically uses cultivated Brassica as a host, regardless of the local composition of wild crucifers. As expected, NSP and MA diversity was independent of the local composition of wild Brassicaceae in P. rapae. In contrast, NSP diversity correlated with local host plant diversity in both species that preferred wild Brassicaceae. Both P. melete and P. napi revealed two distinct major NSP alleles, which shaped diversity among local populations, albeit with different evolutionary trajectories. In comparison, MA showed no indication for local adaptation. Altogether, MA appeared to be evolutionary more conserved than NSP, suggesting that both genes play different roles in diverting host plant chemical defence.


Assuntos
Brassicaceae , Borboletas , Ericaceae , Animais , Brassicaceae/química , Borboletas/genética , Glucosinolatos/genética , Insetos , Larva/genética
5.
Ecol Evol ; 11(11): 6962-6976, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34141268

RESUMO

Latitude is correlated with environmental components that determine the distribution of biodiversity. In combination with geographic factors, latitude-associated environmental variables are expected to influence speciation, but empirical evidence on how those factors interplay is scarce. We evaluated the genetic and environmental variation among populations in the pair of sister species Dioon sonorense-D. vovidesii, two cycads distributed along a latitudinal environmental gradient in northwestern Mexico, to reveal their demographic histories and the environmental factors involved in their divergence. Using genome-wide loci data, we determined the species delimitation, estimated the gene flow, and compared multiple demographic scenarios of divergence. Also, we estimated the variation of climatic variables among populations and used ecological niche models to test niche overlap between species. The effect of geographic and environmental variables on the genetic variation among populations was evaluated using linear models. Our results suggest the existence of a widespread ancestral population that split into the two species ~829 ky ago. The geographic delimitation along the environmental gradient occurs in the absence of major geographic barriers, near the 28th parallel north, where a zonation of environmental seasonality exists. The northern species, D. vovidesii, occurs in more seasonal environments but retains the same niche of the southern species, D. sonorense. The genetic variation throughout populations cannot be solely explained by stochastic processes; the latitudinal-associated seasonality has been an additive factor that strengthened the species divergence. This study represents an example of how speciation can be achieved by the effect of the latitude-associated factors on the genetic divergence among populations.

6.
Nat Chem ; 13(3): 226-230, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33589784

RESUMO

All superheavy elements (SHEs), with atomic numbers (Z) ≥104, have been artificially synthesized one atom at a time and their chemical properties are largely unknown. Because these heavy nuclei have short lifetimes as well as extremely low production rates, chemical experiments need to be carried out on single atoms and have mostly been limited to adsorption and extraction. We have now investigated the precipitation properties of the SHE Rf (Z = 104). A co-precipitation method with samarium hydroxide had previously established that the co-precipitation behaviour of a range of elements reflected these elements' tendency to form hydroxide precipitates and/or ammine complex ions. Here we investigated co-precipitation of Rf in basic solutions containing NH3 or NaOH. Comparisons between the behaviour of Rf with that of Zr and Hf (lighter homologues of Rf) and actinide Th (a pseudo-homologue of Rf) showed that Rf does not coordinate strongly with NH3, but forms a hydroxide (co)precipitate that is expected to be Rf(OH)4.

7.
New Phytol ; 227(6): 1872-1884, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32392621

RESUMO

Niche conservatism is the tendency of lineages to retain the same niche as their ancestors. It constrains biological groups and prevents ecological divergence. However, theory predicts that niche conservatism can hinder gene flow, strengthen drift and increase local adaptation: does it mean that it also can facilitate speciation? Why does this happen? We aim to answer these questions. We examined the variation of chloroplast DNA, genome-wide single nucleotide polymorphisms, morphological traits and environmental variables across the Dioon merolae cycad populations. We tested geographical structure, scenarios of demographic history, and niche conservatism between population groups. Lineage divergence is associated with the presence of a geographical barrier consisting of unsuitable habitats for cycads. There is a clear genetic and morphological distinction between the geographical groups, suggesting allopatric divergence. However, even in contrasting available environmental conditions, groups retain their ancestral niche, supporting niche conservatism. Niche conservatism is a process that can promote speciation. In D. merolae, lineage divergence occurred because unsuitable habitats represented a barrier against gene flow, incurring populations to experience isolated demographic histories and disparate environmental conditions. This study explains why cycads, despite their ancient lineage origin and biological stasis, have been able to diversify into modern ecosystems worldwide.


Assuntos
Zamiaceae , Ecossistema , Especiação Genética , Geografia , México , Filogenia
8.
Ecology ; 101(8): e03064, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32274791

RESUMO

Networks of direct and indirect biotic interactions underpin the complex dynamics and stability of ecological systems, yet experimental and theoretical studies often yield conflicting evidence regarding the direction (positive or negative) or magnitude of these interactions. We revisited pioneering data sets collected at the deciduous forested Horonai Stream and conducted ecosystem-level syntheses to demonstrate that the direction of direct and indirect interactions can change depending on the timescale of observation. Prior experimental studies showed that terrestrial prey that enter the stream from the adjacent forest caused positive indirect effects on aquatic invertebrates during summer by diverting fish consumption. Seasonal and annual estimates of secondary production and organic matter flows along food web pathways demonstrate that this seasonal input of terrestrial invertebrate prey increases production of certain fish species, reversing the indirect effect on aquatic invertebrates from positive at the seasonal timescale to negative at the annual timescale. Even though terrestrial invertebrate prey contributed 54% of the annual organic matter flux to fishes, primarily during summer, fish still consumed 98% of the aquatic invertebrate annual production, leading to top-down control that is not revealed in short-term experiments and demonstrating that aquatic prey may be a limiting resource for fishes. Changes in the direction or magnitude of interactions may be a key factor creating nonlinear or stabilizing feedbacks in complex systems, and these dynamics can be revealed by merging experimental and comparative approaches at different scales.


Assuntos
Ecossistema , Rios , Animais , Cadeia Alimentar , Florestas , Invertebrados
9.
J Clin Biochem Nutr ; 66(2): 158-162, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32231413

RESUMO

Non-steroidal anti-inflammatory drugs (NSAIDs) or low-dose aspirin (LDA) are the most common causes of drug-induced gastroduodenal ulcer and We investigated preventive treatment with use of concomitant anti-ulcer drugs and the clinical features of gastroduodenal ulcer in cases treated with these drugs. Patients with gastroduodenal ulcer and patients with bleeding were classified into 3 groups: LDA, non-aspirin NSAIDs, and those taking neither aspirin nor NSAIDs. Chronological changes over the past 16 years (1st-5th period) were investigated. The status of prevention of ulcer and clinical features were examined. From January 2002 to December 2018, the ratio of all patients taking NSAIDs and LDA increased significantly until 3rd period (p<0.05), but then started to decrease in 4th period; and the percentage of all patients taking NSAIDs and LDA decreased significantly (p<0.05) until 5th period. Among the 292 patients with gastroduodenal ulcer and the 121 patients with a bleeding ulcer taking NSAIDs and LDA, 16 (5.5%) and 9 (7.4%), respectively, were receiving preventive treatment with concomitant anti-ulcer drugs. The percentages of patients taking LDA and other antiplatelet drugs in patients with bleeding gastroduodenal ulcer were significantly higher than those in patients with non-bleeding. In conclusion, although the percentages of patients with gastroduodenal ulcer taking NSAIDs or LDA have not recently increased in real-world practice, preventive treatment in these patients is still low. This low rate of prevention suggests the need to enlighten physicians about preventive treatment because drug withdrawal of LDA has a high risk of cardiovasculr and cerebrovascular events.

10.
Ecol Evol ; 10(24): 14137-14151, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33732431

RESUMO

Assemblages of insect herbivores are structured by plant traits such as nutrient content, secondary metabolites, physical traits, and phenology. Many of these traits are phylogenetically conserved, implying a decrease in trait similarity with increasing phylogenetic distance of the host plant taxa. Thus, a metric of phylogenetic distances and relationships can be considered a proxy for phylogenetically conserved plant traits and used to predict variation in herbivorous insect assemblages among co-occurring plant species.Using a Holarctic dataset of exposed-feeding and shelter-building caterpillars, we aimed at showing how phylogenetic relationships among host plants explain compositional changes and characteristics of herbivore assemblages.Our plant-caterpillar network data derived from plot-based samplings at three different continents included >28,000 individual caterpillar-plant interactions. We tested whether increasing phylogenetic distance of the host plants leads to a decrease in caterpillar assemblage overlap. We further investigated to what degree phylogenetic isolation of a host tree species within the local community explains abundance, density, richness, and mean specialization of its associated caterpillar assemblage.The overlap of caterpillar assemblages decreased with increasing phylogenetic distance among the host tree species. Phylogenetic isolation of a host plant within the local plant community was correlated with lower richness and mean specialization of the associated caterpillar assemblages. Phylogenetic isolation had no effect on caterpillar abundance or density. The effects of plant phylogeny were consistent across exposed-feeding and shelter-building caterpillars.Our study reveals that distance metrics obtained from host plant phylogeny are useful predictors to explain compositional turnover among hosts and host-specific variations in richness and mean specialization of associated insect herbivore assemblages in temperate broadleaf forests. As phylogenetic information of plant communities is becoming increasingly available, further large-scale studies are needed to investigate to what degree plant phylogeny structures herbivore assemblages in other biomes and ecosystems.

11.
PeerJ ; 8: e10625, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33391886

RESUMO

Herbivorous insects are thought to have evolved counteradaptations to conquer chemical defenses in their host plants in a stepwise co-evolutionary process. Papilio butterflies use CYP6B gene family members to metabolize furanocoumarins in their Rutaceae or Apiaceae host plants. CYP6Bs have functionally diverged among Papilio species to be able to metabolite diverse types of furanocoumarins in their host plants. In this study, we examined the diversification and selection patterns of CYP6B among nine Papilio species in Japan (eight Rutaceae specialists and one Apiaceae specialist) and their association with host plant spectra and furanocoumarin profiles. We compared host plant spectrum of eight Rutaceae feeding Papilio species and also performed a furanocoumarin profiling of their host plants. In addition, we reconstructed CYP6B gene phylogeny and performed selection analysis based on the transcriptome data of those nine Papilio species. Among Rutaceae-feeding Papilio species, host plant spectrum differences were correlated with their furanocoumarin profiles. However, all tested Papilio species had similar duplicated sets of CYP6B, with no apparent lineage-specific or host plant-specific pattern of CYP6B diversification. Selection analysis showed a signature of positive selection on a CYP6B branch. The positively selected sites located at predicted substrate recognition sites and we also found that these CYP6B genes were observed only in Rutaceae-feeding species. These findings indicate that most CYP6B diversification occurred in ancestral species of these Papilio species, possibly in association with specific host plant chemical defenses and subsequent gene loss due to host specialization. These processes would have shaped the complex diversification patterns of the CYP6B gene family in Papilio butterflies. Our results also show potentially important CYP6B clades among Papilio species which likely to have diverged functions and associated with host plant phytochemicals in ancestral Papilio species.

12.
Mol Ecol ; 28(22): 4958-4970, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31597214

RESUMO

Adaptive traits that enable organisms to conquer novel niches and experience subsequent diversification are ecologically and evolutionarily important. The larvae of Pieris butterflies express nitrile-specifier proteins (NSPs), a key innovation for overcoming the glucosinolate (GLS)-myrosinase-based defence system of their Brassicales host plants. Nitrile-specifier proteins are a member of the NSP-like gene family, which includes the major allergen (MA) protein, a paralog of NSP with a GLS-disarming function, and a single domain major allergen (SDMA) protein, whose function is unknown. The arms-race between GLS-based defences and the NSP-like gene family is suggested to mediate diversification in both Pierid butterflies and Brassicales plants. Here, we tested whether the expected strong selection on NSP-like gene family correlates with shifts in host plant spectra among Pierid butterflies. We combined feeding experiments using 25 Brassicaceae plants and five Pieris species with larval transcriptome data to investigate the patterns of selection acting on NSP-like gene family members. Although we observed significantly elevated nonsynonymous to synonymous substitution rate ratios in NSPs on branches associated with changes in patterns of host plant usage, no such pattern was observed in MAs or SDMAs. Furthermore, we found evidence for positive selection of NSP at a phylogenetic branch which reflects different host plant spectra. Our data indicate that the NSP-related gene members have evolved differently: NSPs have accumulated more amino acid changes in response to shifting preferences for host plants, whereas MAs and SDMAs appear to be more conserved. Further detailed functional assays of these genes would provide important insights to understand their role in the chemical arms-race between Pieris butterflies and their Brassicales host plants.


Assuntos
Borboletas/genética , Interações Hospedeiro-Parasita/genética , Animais , Evolução Biológica , Brassicaceae/genética , Brassicaceae/parasitologia , Glucosinolatos/genética , Proteínas de Insetos/genética , Larva/genética , Filogenia , Transcriptoma/genética
13.
PLoS One ; 14(10): e0222119, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644586

RESUMO

Research on canopy arthropods has progressed from species inventories to the study of their interactions and networks, enhancing our understanding of how hyper-diverse communities are maintained. Previous studies often focused on sampling individual tree species, individual trees or their parts. We argue that such selective sampling is not ideal when analyzing interaction network structure, and may lead to erroneous conclusions. We developed practical and reproducible sampling guidelines for the plot-based analysis of arthropod interaction networks in forest canopies. Our sampling protocol focused on insect herbivores (leaf-chewing insect larvae, miners and gallers) and non-flying invertebrate predators (spiders and ants). We quantitatively sampled the focal arthropods from felled trees, or from trees accessed by canopy cranes or cherry pickers in 53 0.1 ha forest plots in five biogeographic regions, comprising 6,280 trees in total. All three methods required a similar sampling effort and provided good foliage accessibility. Furthermore, we compared interaction networks derived from plot-based data to interaction networks derived from simulated non-plot-based data focusing either on common tree species or a representative selection of tree families. All types of non-plot-based data showed highly biased network structure towards higher connectance, higher web asymmetry, and higher nestedness temperature when compared with plot-based data. Furthermore, some types of non-plot-based data showed biased diversity of the associated herbivore species and specificity of their interactions. Plot-based sampling thus appears to be the most rigorous approach for reconstructing realistic, quantitative plant-arthropod interaction networks that are comparable across sites and regions. Studies of plant interactions have greatly benefited from a plot-based approach and we argue that studies of arthropod interactions would benefit in the same way. We conclude that plot-based studies on canopy arthropods would yield important insights into the processes of interaction network assembly and dynamics, which could be maximised via a coordinated network of plot-based study sites.


Assuntos
Artrópodes/fisiologia , Interações Hospedeiro-Parasita , Plantas/parasitologia , Animais , Florestas , Larva/fisiologia , Árvores/parasitologia
14.
J Insect Sci ; 19(3)2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31039584

RESUMO

The tremendous diversity of plants and herbivores has arisen from a coevolutionary relationship characterized by plant defense and herbivore counter adaptation. Pierid butterfly species feed on Brassicales plants that produce glucosinolates as a chemical deterrent against herbivory. In turn, the larvae of pierids have nitrile specifier proteins (NSPs) that are expressed in their gut and disarm glucosinolates. Pierid butterflies are known to have diversified in response to glucosinolate diversification in Brassicales. Therefore, each pierid species is expected to have a spectrum of host plants characterized by specific glucosinolate profiles. In this study, we tested whether the larval performance of different Pieris species, a genus in Pieridae (Lepidoptera: Pieridae), was associated with plant defense traits of putative host plants. We conducted feeding assays using larvae of three Pieris species and 10 species of the Brassicaceae family possessing different leaf physical traits and glucosinolate profile measurements. The larvae of Pieris rapae responded differently in the feeding assays compared with the other two Pieris species. This difference was associated with differences in glucosinolate profiles but not with variations in physical traits of the host plants. This result suggests that individual Pieris species are adapted to a subset of glucosinolate profiles within the Brassicaceae. Our results support the idea that the host ranges of Pieris species depend on larval responses to glucosinolate diversification in the host species, supporting the hypothesis of coevolution between butterflies and host plants mediated by the chemical arms race.


Assuntos
Brassica/química , Borboletas/crescimento & desenvolvimento , Cardamine/química , Glucosinolatos , Herbivoria , Adaptação Biológica , Animais , Brassica/anatomia & histologia , Cardamine/anatomia & histologia , Feminino , Larva/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Folhas de Planta/química , Especificidade da Espécie
15.
Sci Rep ; 9(1): 7256, 2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-31076616

RESUMO

Specialist herbivores have often evolved highly sophisticated mechanisms to counteract defenses mediated by major plant secondary-metabolites. Plant species of the herbivore host range often display high chemical diversity and it is not well understood how specialist herbivores respond to this chemical diversity. Pieris larvae overcome toxic products from glucosinolate hydrolysis, the major chemical defense of their Brassicaceae hosts, by expressing nitrile-specifier proteins (NSP) in their gut. Furthermore, Pieris butterflies possess so-called major allergen (MA) proteins, which are multi-domain variants of a single domain major allergen (SDMA) protein expressed in the guts of Lepidopteran larvae. Here we show that Pieris larvae fine-tune NSP and MA gene expression depending on the glucosinolate profiles of their Brassicaceae hosts. Although the role of MA is not yet fully understood, the expression levels of NSP and MA in larvae that fed on plants whose glucosinolate composition varied was dramatically changed, whereas levels of SDMA expression remained unchanged. In addition, we found a similar regulation pattern among these genes in larvae feeding on Arabidopsis mutants with different glucosinolate profiles. Our results demonstrate that Pieris larvae appear to use different host plant adaptive genes to overcome a wide range of glucosinolate profiles in their host plants.


Assuntos
Adaptação Biológica/genética , Borboletas/genética , Ericaceae/genética , Glucosinolatos/genética , Alérgenos/genética , Animais , Arabidopsis/genética , Genes de Plantas/genética , Larva/genética
16.
Sci Rep ; 8(1): 6691, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29703935

RESUMO

The effects of the Japanese horned beetle larvae on the transfer of 137Cs from a contaminated leaf litter to the leaf vegetable, komatsuna (Brassica rapa var. perviridis) was studied. Feces of the larvae which were fed 137Cs-contaminated leaf litter were added to a potting mix in which komatsuna plants were cultivated. The presence of feces increased the harvest yield of komatsuna, suggesting that feces provided nutrients for the plant growth. In addition, the amount of exchangeable 137Cs in leaf litter was experimentally confirmed to be enhanced by the presence of feces which were excreted by larvae feeding. However, there was no difference in the soil-to-plant transfer factor of 137Cs for the presence and absence of feces. Interactions between clay minerals and exchangeable 137Cs in the soil beneath the litter layer may diminish the root uptake of 137Cs. From these results, it was concluded that the effect of exchangeable 137Cs released from feces was limited for the transfer of 137Cs to plants if plant roots were not present in litter layers.


Assuntos
Brassica rapa/parasitologia , Besouros/fisiologia , Interações Hospedeiro-Parasita , Larva/fisiologia , Animais , Radioisótopos de Césio/análise , Fezes/química , Marcação por Isótopo
17.
Inflamm Bowel Dis ; 24(5): 1035-1044, 2018 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-29688473

RESUMO

Background: Dysbiosis, especially a reduced Clostridium subcluster XIVa (XIVa), has been reported in several gastrointestinal diseases. Since XIVa is thought to be the main bacterial cluster that metabolizes bile acids (BAs) in the human intestine, we hypothesized that the BA profile in feces, and possibly in serum, could be a convenient biomarker for intestinal XIVa activity. Methods: First, blood and feces were collected from 26 healthy controls and 20 patients with gastrointestinal diseases, and the relationships among fecal microbiomes and fecal and serum BA compositions were studied. Second, serum BA compositions of 30 healthy controls and the remission and exacerbation states of 14 Crohn's disease (CD) and 12 ulcerative colitis (UC) patients were compared. Fecal microbiomes were analyzed by terminal restriction fragment length polymorphism analysis, and BA compositions were quantified by HPLC-MS/MS. Results: The highest positive correlation was observed between the fecal XIVa proportion and fecal unconjugated deoxycholic acid (DCA)/(DCA+unconjugated cholic acid [CA]) (r = 0.77, P < 0.0001) or serum DCA/(DCA+CA) (r = 0.52, P < 0.001). Diurnal variation in serum XIVa candidate markers also showed that DCA/(DCA+CA) was most stable and not affected by the contraction of the gallbladder. Serum DCA/(DCA+CA) was not significantly different between remission and exacerbation states in either CD or UC patients, but was significantly reduced in those in the remission state of CD and the remission and exacerbation states of UC compared with healthy controls (P < 0.05). Conclusions: Decreased XIVa exhibits a strong correlation with reduced intestinal BA metabolism. Fecal and serum DCA/(DCA+CA) could be useful surrogate markers for the intestinal proportion of XIVa.


Assuntos
Ácidos e Sais Biliares/análise , Colite Ulcerativa/diagnóstico , Doença de Crohn/diagnóstico , Disbiose/diagnóstico , Microbioma Gastrointestinal , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão , Clostridium/metabolismo , Colite Ulcerativa/microbiologia , Doença de Crohn/microbiologia , Disbiose/microbiologia , Fezes/química , Feminino , Humanos , Intestinos/microbiologia , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem , Adulto Jovem
18.
Intern Med ; 57(3): 339-342, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29093413

RESUMO

A 66-year-old Japanese male with a history of Behçet disease exhibited oral and genital ulcers, and a round deep ileocecal ulcer. He was treated with a combination of mesalazine and 20 mg/day of prednisolone (PSL), but was only partially responsive to PSL and we were not able to reduce the steroid dosage. Adalimumab was also administered. However, the ulcer was not completely responsive, and weaning the patient off PSL remained impossible. In contrast, additional treatment with clarithromycin completely healed the refractory active ulcer and left only a scar. Furthermore, the ulcer has since maintained the scar stage despite successfully weaning the patient from PSL.


Assuntos
Adalimumab/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Síndrome de Behçet/tratamento farmacológico , Doenças do Ceco/tratamento farmacológico , Claritromicina/uso terapêutico , Doenças do Íleo/tratamento farmacológico , Úlcera/tratamento farmacológico , Idoso , Quimioterapia Combinada , Humanos , Masculino , Mesalamina/uso terapêutico , Prednisolona/uso terapêutico
19.
Stem Cell Res Ther ; 8(1): 61, 2017 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-28279187

RESUMO

BACKGROUND: Experiments have previously demonstrated the therapeutic potential of mobilized dental pulp stem cells (MDPSCs) for complete pulp regeneration. The aim of the present pilot clinical study is to assess the safety, potential efficacy, and feasibility of autologous transplantation of MDPSCs in pulpectomized teeth. METHODS: Five patients with irreversible pulpitis were enrolled and monitored for up to 24 weeks following MDPSC transplantation. The MDPSCs were isolated from discarded teeth and expanded based on good manufacturing practice (GMP). The quality of the MDPSCs at passages 9 or 10 was ascertained by karyotype analyses. The MDPSCs were transplanted with granulocyte colony-stimulating factor (G-CSF) in atelocollagen into pulpectomized teeth. RESULTS: The clinical and laboratory evaluations demonstrated no adverse events or toxicity. The electric pulp test (EPT) of the pulp at 4 weeks demonstrated a robust positive response. The signal intensity of magnetic resonance imaging (MRI) of the regenerated tissue in the root canal after 24 weeks was similar to that of normal dental pulp in the untreated control. Finally, cone beam computed tomography demonstrated functional dentin formation in three of the five patients. CONCLUSIONS: Human MDPSCs are safe and efficacious for complete pulp regeneration in humans in this pilot clinical study.


Assuntos
Polpa Dentária/crescimento & desenvolvimento , Pulpite/terapia , Regeneração/genética , Transplante de Células-Tronco , Dente/crescimento & desenvolvimento , Adulto , Diferenciação Celular/genética , Proliferação de Células/genética , Polpa Dentária/diagnóstico por imagem , Polpa Dentária/patologia , Feminino , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pulpite/patologia , Pulpite/cirurgia , Células-Tronco/citologia , Dente/diagnóstico por imagem , Dente/patologia , Dente/cirurgia
20.
J Anim Ecol ; 86(3): 556-565, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28146344

RESUMO

Insects tend to feed on related hosts. The phylogenetic composition of host plant communities thus plays a prominent role in determining insect specialization, food web structure, and diversity. Previous studies showed a high preference of insect herbivores for congeneric and confamilial hosts suggesting that some levels of host plant relationships may play more prominent role that others. We aim to quantify the effects of host phylogeny on the structure of quantitative plant-herbivore food webs. Further, we identify specific patterns in three insect guilds with different life histories and discuss the role of host plant phylogeny in maintaining their diversity. We studied herbivore assemblages in three temperate forests in Japan and the Czech Republic. Sampling from a canopy crane, a cherry picker and felled trees allowed a complete census of plant-herbivore interactions within three 0·1 ha plots for leaf chewing larvae, miners, and gallers. We analyzed the effects of host phylogeny by comparing the observed food webs with randomized models of host selection. Larval leaf chewers exhibited high generality at all three sites, whereas gallers and miners were almost exclusively monophagous. Leaf chewer generality dropped rapidly when older host lineages (5-80 myr) were collated into a single lineage but only decreased slightly when the most closely related congeneric hosts were collated. This shows that leaf chewer generality has been maintained by feeding on confamilial hosts while only a few herbivores were shared between more distant plant lineages and, surprisingly, between some congeneric hosts. In contrast, miner and galler generality was maintained mainly by the terminal nodes of the host phylogeny and dropped immediately after collating congeneric hosts into single lineages. We show that not all levels of host plant phylogeny are equal in their effect on structuring plant-herbivore food webs. In the case of generalist guilds, it is the phylogeny of deeper plant lineages that drives the food web structure whereas the terminal relationships play minor roles. In contrast, the specialization and abundance of monophagous guilds are affected mainly by the terminal parts of the plant phylogeny and do not generally reflect deeper host phylogeny.


Assuntos
Cadeia Alimentar , Florestas , Herbivoria , Insetos/fisiologia , Magnoliopsida/classificação , Filogenia , Animais , República Tcheca , Insetos/crescimento & desenvolvimento , Japão , Larva/fisiologia , Folhas de Planta/fisiologia
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