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1.
Proc Natl Acad Sci U S A ; 117(45): 28140-28149, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33093203

RESUMO

Land-use intensification can increase provisioning ecosystem services, such as food and timber production, but it also drives changes in ecosystem functioning and biodiversity loss, which may ultimately compromise human wellbeing. To understand how changes in land-use intensity affect the relationships between biodiversity, ecosystem functions, and services, we built networks from correlations between the species richness of 16 trophic groups, 10 ecosystem functions, and 15 ecosystem services. We evaluated how the properties of these networks varied across land-use intensity gradients for 150 forests and 150 grasslands. Land-use intensity significantly affected network structure in both habitats. Changes in connectance were larger in forests, while changes in modularity and evenness were more evident in grasslands. Our results show that increasing land-use intensity leads to more homogeneous networks with less integration within modules in both habitats, driven by the belowground compartment in grasslands, while forest responses to land management were more complex. Land-use intensity strongly altered hub identity and module composition in both habitats, showing that the positive correlations of provisioning services with biodiversity and ecosystem functions found at low land-use intensity levels, decline at higher intensity levels. Our approach provides a comprehensive view of the relationships between multiple components of biodiversity, ecosystem functions, and ecosystem services and how they respond to land use. This can be used to identify overall changes in the ecosystem, to derive mechanistic hypotheses, and it can be readily applied to further global change drivers.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Modelos Biológicos , Florestas , Pradaria
2.
Biofouling ; 35(7): 805-817, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31538816

RESUMO

To avoid the negative impacts caused by biofouling development, aquaculture nets around the world are periodically cleaned using high-pressure washers. Net cleaning is labour-intense and costly, can damage antifouling coatings on the nets, and pose contamination as well as fish health and welfare risks. To support the environmental sustainability of the growing aquaculture sector, novel net cleaning methods are needed. This study examined low-pressure-, cavitation-, and suction-based cleaning technologies as alternatives to conventional high-pressure cleaning. Using field experiments, cleaning efficacy, cleaning waste generation, and the impact of cleaning on coating integrity and net strength were evaluated. Cavitation and high-pressure cleaning achieved considerably higher cleaning efficacy than low-pressure and suction cleaning. However, a single high-pressure treatment caused up to 53% coating degradation, compared to 2% for cavitation. All technologies produced similar cleaning waste and neither reduced net strength significantly. This study identifies cavitation cleaning as promising technology for biofouling control on aquaculture nets.


Assuntos
Aquicultura , Peixes , Animais , Incrustação Biológica , Tecnologia
3.
Nat Commun ; 9(1): 4839, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30446752

RESUMO

Trade-offs and synergies in the supply of forest ecosystem services are common but the drivers of these relationships are poorly understood. To guide management that seeks to promote multiple services, we investigated the relationships between 12 stand-level forest attributes, including structure, composition, heterogeneity and plant diversity, plus 4 environmental factors, and proxies for 14 ecosystem services in 150 temperate forest plots. Our results show that forest attributes are the best predictors of most ecosystem services and are also good predictors of several synergies and trade-offs between services. Environmental factors also play an important role, mostly in combination with forest attributes. Our study suggests that managing forests to increase structural heterogeneity, maintain large trees, and canopy gaps would promote the supply of multiple ecosystem services. These results highlight the potential for forest management to encourage multifunctional forests and suggest that a coordinated landscape-scale strategy could help to mitigate trade-offs in human-dominated landscapes.


Assuntos
Conservação dos Recursos Naturais/métodos , Agricultura Florestal/métodos , Florestas , Árvores/fisiologia , Ecossistema , Europa (Continente) , Agricultura Florestal/tendências , Humanos
4.
Ecol Lett ; 21(8): 1229-1236, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29938888

RESUMO

At the global scale, species diversity is known to strongly increase towards the equator for most taxa. According to theory, a higher resource specificity of consumers facilitates the coexistence of a larger number of species and has been suggested as an explanation for the latitudinal diversity gradient. However, only few studies support the predicted increase in specialisation or even showed opposite results. Surprisingly, analyses for detritivores are still missing. Therefore, we performed an analysis on the degree of trophic specialisation of dung beetles. We summarised 45 studies, covering the resource preferences of a total of 994503 individuals, to calculate the dung specificity in each study region. Our results highlighted a significant (4.3-fold) increase in the diversity of beetles attracted to vertebrate dung towards the equator. However, their resource specificity was low, unrelated to diversity and revealed a highly generalistic use of dung resources that remained similar along the latitudinal gradient.


Assuntos
Biodiversidade , Besouros , Cadeia Alimentar , Animais , Fezes , Estado Nutricional
5.
Artigo em Inglês | MEDLINE | ID: mdl-32832832

RESUMO

PURPOSE: Brain tumors have become the leading cause of cancer-related mortality in young patients. Novel effective therapies on the basis of the unique biology of each tumor are urgently needed. The goal of this study was to evaluate the feasibility, utility, and clinical impact of integrative clinical sequencing and genetic counseling in children and young adults with high-risk brain tumors. PATIENTS AND METHODS: Fifty-two children and young adults with brain tumors designated by the treating neuro-oncologist to be high risk (> 25% chance for treatment failure; mean age, 10.2 years; range, 0 to 39 years) were enrolled in a prospective, observational, consecutive case series, in which participants underwent integrative clinical exome (tumor and germline DNA) and transcriptome (tumor RNA) sequencing and genetic counseling. Results were discussed in a multi-institutional brain tumor precision medicine teleconference. RESULTS: Sequencing revealed a potentially actionable germline or tumor alteration in 25 (63%) of 40 tumors with adequate tissue, of which 21 (53%) resulted in an impact on treatment or change of diagnosis. Platelet-derived growth factor receptor or fibroblast growth factor receptor pathway alterations were seen in nine of 20 (45%) glial tumors. Eight (20%) sequenced tumors harbored an oncogenic fusion isolated on RNA sequencing. Seventeen of 20 patients (85%) with glial tumors were found to have a potentially actionable result, which resulted in change of therapy in 14 (70%) patients. Patients with recurrent brain tumors receiving targeted therapy had a median progression-free survival (from time on therapy) of 4 months. CONCLUSION: Selection of personalized agents for children and young adults with highrisk brain tumors on the basis of integrative clinical sequencing is feasible and resulted in a change in therapy in more than two thirds of children and young adults with high-risk glial tumors.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32832831

RESUMO

PURPOSE: Evidence-based guidelines inform treatment decisions for patients for whom germline genetic information is available. Our real-time tumor sequencing program, which makes precision treatment decisions for patients with cancer, produces matched germline information, providing a unique opportunity to efficiently implement pharmacogenetics and benefit patients. METHODS: The germline genetic database from the Michigan Oncology Sequencing (MI-Oncoseq) program was searched for 21 clinically actionable polymorphisms in five cancer-relevant genes: TPMT, DPYD, CYP2C19, CYP3A5, and UGT1A1. Residual germ line DNA was sent to an external Clinical Laboratory Improvement Amendments-approved laboratory for confirmatory genotyping. The medical records of MI-Oncoseq patients with actionable phenotypes were searched for receipt of relevant drugs and to determine whether having genetic information at the time of treatment would have led to a treatment recommendation. RESULTS: All nine variants in TPMT, DPYD, and CYP2C19 that were detected in MI-Oncoseq were confirmed by external genotyping. Genotype determinations could not be made for CYP3A5*3, UGT1A1*28, or UGT1A1*80. On the basis of retrospective assessment of 115 adult and pediatric patient records, 4.3% (n = 5) had a potentially clinically actionable phenotype for TPMT, DPYD, or CYP2C19 and received a relevant medication. After accounting for differences in adult and pediatric recommendations, three of these patients could have received a treatment recommendation at the time of prescribing. CONCLUSION: Germline genotype determinations for TPMT, DPYD, and CYP2C19 can be used to make evidence-based treatment recommendations in MI-Oncoseq patients. Although the proportion of patients for whom recommendations can be made is small, this added value to MI-Oncoseq and patient care comes at no additional genotyping cost. Pharmacogenetic assessment should be integrated into tumor sequencing programs that genotype matched germline DNA; however, the complexity and additional cost of implementing pharmacogenetics remain challenging.

7.
Sci Rep ; 7(1): 12141, 2017 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-28939910

RESUMO

At the basis of a trophic web, coprophagous animals like dung beetles (Scarabaeoidea) utilize resources that may have advantages (easy gain and handling) as well as drawbacks (formerly processed food). Several studies have characterized the nutrients, e.g. C/N ratios and organic matter content, for specific types of dung. However, a comparative approach across dung types and feeding guilds of dung producers, and relationships between dung nutrients and preferences by coprophages, have been missing. Hence, we analyzed water content, C/N ratio, amino acid, neutral lipid fatty acid, free fatty acid and sterol composition and concentrations in dung from 23 vertebrates, including carnivore, omnivore and herbivore species. Our analyses revealed significant differences among the three vertebrate feeding guilds for most nutritional parameters. Although formerly processed, dung grants sufficient amounts of essential nutrients for insects. We tested whether nutrients can explain the dung beetles' preferences in a field experiment, using 12 representative dung types in baits that were installed in 27 forests and 27 grasslands. Although consistent preferences for specific dung types were pronounced, the nutritional composition did not predict the variation in attractiveness of these dung diets, suggesting a primary role of dung volatiles irrespective of food quality.


Assuntos
Besouros/fisiologia , Comportamento Alimentar , Esterco/análise , Nutrientes/análise , Aminoácidos/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Lipídeos/análise , Esteróis/análise , Água/análise
8.
JAMA ; 314(9): 913-25, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26325560

RESUMO

IMPORTANCE: Cancer is caused by a diverse array of somatic and germline genomic aberrations. Advances in genomic sequencing technologies have improved the ability to detect these molecular aberrations with greater sensitivity. However, integrating them into clinical management in an individualized manner has proven challenging. OBJECTIVE: To evaluate the use of integrative clinical sequencing and genetic counseling in the assessment and treatment of children and young adults with cancer. DESIGN, SETTING, AND PARTICIPANTS: Single-site, observational, consecutive case series (May 2012-October 2014) involving 102 children and young adults (mean age, 10.6 years; median age, 11.5 years, range, 0-22 years) with relapsed, refractory, or rare cancer. EXPOSURES: Participants underwent integrative clinical exome (tumor and germline DNA) and transcriptome (tumor RNA) sequencing and genetic counseling. Results were discussed by a precision medicine tumor board, which made recommendations to families and their physicians. MAIN OUTCOMES AND MEASURES: Proportion of patients with potentially actionable findings, results of clinical actions based on integrative clinical sequencing, and estimated proportion of patients or their families at risk of future cancer. RESULTS: Of the 104 screened patients, 102 enrolled with 91 (89%) having adequate tumor tissue to complete sequencing. Only the 91 patients were included in all calculations, including 28 (31%) with hematological malignancies and 63 (69%) with solid tumors. Forty-two patients (46%) had actionable findings that changed their cancer management: 15 of 28 (54%) with hematological malignancies and 27 of 63 (43%) with solid tumors. Individualized actions were taken in 23 of the 91 (25%) based on actionable integrative clinical sequencing findings, including change in treatment for 14 patients (15%) and genetic counseling for future risk for 9 patients (10%). Nine of 91 (10%) of the personalized clinical interventions resulted in ongoing partial clinical remission of 8 to 16 months or helped sustain complete clinical remission of 6 to 21 months. All 9 patients and families with actionable incidental genetic findings agreed to genetic counseling and screening. CONCLUSIONS AND RELEVANCE: In this single-center case series involving young patients with relapsed or refractory cancer, incorporation of integrative clinical sequencing data into clinical management was feasible, revealed potentially actionable findings in 46% of patients, and was associated with change in treatment and family genetic counseling for a small proportion of patients. The lack of a control group limited assessing whether better clinical outcomes resulted from this approach than outcomes that would have occurred with standard care.


Assuntos
Aconselhamento Genético , Neoplasias/genética , Análise de Sequência de DNA/métodos , Adolescente , Criança , Pré-Escolar , Aberrações Cromossômicas , Família , Estudos de Viabilidade , Fusão Gênica , Neoplasias Hematológicas/genética , Humanos , Achados Incidentais , Lactente , Recém-Nascido , Terapia de Alvo Molecular/métodos , Recidiva Local de Neoplasia/genética , Neoplasias/terapia , Avaliação de Resultados em Cuidados de Saúde , Indução de Remissão , Adulto Jovem
9.
PLoS One ; 10(5): e0126140, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25938417

RESUMO

Most forests are exposed to anthropogenic management activities that affect tree species composition and natural ecosystem processes. Changes in ecosystem processes such as herbivory depend on management intensity, and on regional environmental conditions and species pools. Whereas influences of specific forest management measures have already been addressed for different herbivore taxa on a local scale, studies considering effects of different aspects of forest management across different regions are rare. We assessed the influence of tree species composition and intensity of harvesting activities on arthropod herbivores and herbivore-related damage to beech trees, Fagus sylvatica, in 48 forest plots in three regions of Germany. We found that herbivore abundance and damage to beech trees differed between regions and that - despite the regional differences - density of tree-associated arthropod taxa and herbivore damage were consistently affected by tree species composition and harvest intensity. Specifically, overall herbivore damage to beech trees increased with increasing dominance of beech trees - suggesting the action of associational resistance processes - and decreased with harvest intensity. The density of leaf chewers and mines was positively related to leaf damage, and several arthropod groups responded to beech dominance and harvest intensity. The distribution of damage patterns was consistent with a vertical shift of herbivores to higher crown layers during the season and with higher beech dominance. By linking quantitative data on arthropod herbivore abundance and herbivory with tree species composition and harvesting activity in a wide variety of beech forests, our study helps to better understand the influence of forest management on interactions between a naturally dominant deciduous forest tree and arthropod herbivores.


Assuntos
Ecossistema , Fagus , Herbivoria , Folhas de Planta , Árvores , Biodiversidade , Florestas , Alemanha
10.
Brain Res Bull ; 85(1-2): 58-63, 2011 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-21371538

RESUMO

Piracetam, a derivative of γ-aminobutyric acid, exerts memory-enhancing and mild anxiolytic effects in human and rodent studies. To examine the drug's behavioral profile further, we assessed its effects on behavioral and endocrine (cortisol) responses of adult zebrafish (Danio rerio)--a novel model species rapidly gaining popularity in neurobehavioral research. Overall, acute piracetam did not affect zebrafish novel tank and light-dark box behavior at mild doses (25-400mg/L), but produced nonspecific behavioral inhibition at 700mg/L. No effects on cortisol levels or inter-/intra-session habituation in the novel tank test were observed for acute or chronic mild non-sedative dose of 200mg/L. In contrast, fish exposed to chronic piracetam at this dose performed significantly better in the cued learning plus-maze test. This observation parallels clinical and rodent literature on the behavioral profile of piracetam, supporting the utility of zebrafish paradigms for testing nootropic agents.


Assuntos
Comportamento Animal/efeitos dos fármacos , Memória/efeitos dos fármacos , Nootrópicos/farmacologia , Piracetam/farmacologia , Peixe-Zebra/fisiologia , Animais , Feminino , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos
11.
Nat Protoc ; 5(11): 1786-99, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21030954

RESUMO

Several behavioral assays are currently used for high-throughput neurophenotyping and screening of genetic mutations and psychotropic drugs in zebrafish (Danio rerio). In this protocol, we describe a battery of two assays to characterize anxiety-related behavioral and endocrine phenotypes in adult zebrafish. Here, we detail how to use the 'novel tank' test to assess behavioral indices of anxiety (including reduced exploration, increased freezing behavior and erratic movement), which are quantifiable using manual registration and computer-aided video-tracking analyses. In addition, we describe how to analyze whole-body zebrafish cortisol concentrations that correspond to their behavior in the novel tank test. This protocol is an easy, inexpensive and effective alternative to other methods of measuring stress responses in zebrafish, thus enabling the rapid acquisition and analysis of large amounts of data. As will be shown here, fish anxiety-like behavior can be either attenuated or exaggerated depending on stress or drug exposure, with cortisol levels generally expected to parallel anxiety behaviors. This protocol can be completed over the course of 2 d, with a variable testing duration depending on the number of fish used.


Assuntos
Comportamento Animal , Neurociências/métodos , Peixe-Zebra/fisiologia , Animais , Hidrocortisona/análise , Modelos Animais , Estresse Fisiológico
12.
Brain Res ; 1348: 209-15, 2010 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-20547142

RESUMO

Larval zebrafish (Danio rerio) have recently been suggested as a high-throughput experimental model of epilepsy-related pathogenetic states. Here we use adult zebrafish to study behavioral symptoms associated with drug-evoked seizures. Experimental epilepsy-like states were evoked in zebrafish by exposure for 20min to three chemoconvulsant drugs: caffeine (250mg/L; 1.3mM), pentylenetetrazole (1.5g/L; 11.0mM) and picrotoxin (100mg/L; 0.17mM). Fish behavior was analyzed using manual and video-tracking methods (Noldus Ethovision XT7). Compared to their respective controls, all three drug-treated groups showed robust seizure-like responses (hyperactivity bouts, spasms, circular and corkscrew swimming) accompanied by elevated whole-body cortisol levels (assessed by ELISA). In contrast, control fish did not display seizure-like behaviors and had significantly lower cortisol levels. Paralleling behavioral and endocrine phenotypes observed in clinical and rodent studies, our data implicates adult zebrafish as an emerging experimental model for epilepsy research.


Assuntos
Comportamento Animal/fisiologia , Modelos Animais de Doenças , Hidrocortisona/metabolismo , Fenótipo , Convulsões/metabolismo , Convulsões/fisiopatologia , Animais , Comportamento Animal/efeitos dos fármacos , Cafeína , Ensaio de Imunoadsorção Enzimática , Feminino , Locomoção/efeitos dos fármacos , Masculino , Análise Numérica Assistida por Computador , Pentilenotetrazol , Picrotoxina , Tempo de Reação/efeitos dos fármacos , Convulsões/induzido quimicamente , Estatísticas não Paramétricas , Peixe-Zebra
13.
J Econ Entomol ; 100(1): 136-47, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17370821

RESUMO

A 2-yr study was conducted to document the influence of selected buffalograss, Buchloë dactyloides (Nuttall) Engelmann, management practices (three mowing heights and five nitrogen levels) on the seasonal abundance of the western chinch bug, Blissus occiduus Barber (Heteroptera: Lygaeidae), and its beneficial arthropods. Vacuum, pitfall, and sticky traps samples were collected every 14 d from the middle of May through October from western chinch bug-resistant ('Prestige') and -susceptible ('378') buffalograss management plots. In total, 27,374 and 108,908 western chinch bugs were collected in vacuum and pitfall traps, respectively. More than 78% of all western chinch bugs were collected from the highly susceptible buffalograss 378. Significantly more bigeyed bugs (Geocoridae: Geocoris spp.) were collected from the 378 buffalograsss management plots than the Prestige plots. In contrast, buffalograss cultivar had little influence on the abundance of other beneficial arthropods collected. Statistically, western chinch bugs were least abundant at the lowest mowing height (2.5 cm) and increased in abundance with increasing fertility. Numerically, however, differences among management levels on western chinch bug abundance were minimal. Numerous beneficial arthropods were collected from buffalograss management plots, including spiders, predatory ants, ground beetles (Carabidae), rove beetles (Staphylinidae), bigeyed bugs, and several species of hymenopterous parasitoids. In general, beneficial arthropods were essentially unaffected by either mowing height or nitrogen level. Scelionid wasps represented 66.3% of the total parasitoids collected. The total number of scelionid wasps collected among the three mowing heights and five nitrogen levels were approximately equal.


Assuntos
Heterópteros/fisiologia , Poaceae/fisiologia , Animais , Formigas/fisiologia , Besouros/fisiologia , Ecossistema , Fertilizantes , Nitrogênio/metabolismo , Densidade Demográfica , Estações do Ano , Aranhas/fisiologia , Fatores de Tempo , Vespas/fisiologia
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