987 resultados para Invasive Plants
Resumo:
Plants produce a range of biopolymers for purposes such as maintenance of structural integrity, carbon storage, and defense against pathogens and desiccation. Several of these natural polymers are used by humans as food and materials, and increasingly as an energy carrier. In this review, we focus on plant biopolymers that are used as materials in bulk applications, such as plastics and elastomers, in the context of depleting resources and climate change, and consider technical and scientific bottlenecks in the production of novel or improved materials in transgenic or alternative crop plants. The biopolymers discussed are natural rubber and several polymers that are not naturally produced in plants, such as polyhydroxyalkanoates, fibrous proteins and poly-amino acids. In addition, monomers or precursors for the chemical synthesis of biopolymers, such as 4-hydroxybenzoate, itaconic acid, fructose and sorbitol, are discussed briefly
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BACKGROUND: Minimally invasive surgery (MIS) for late-presenting congenital diaphragmatic hernia (CDH) has been described previously, but few neonatal cases of CDH have been reported. This study aimed to report the multicenter experience of these rare cases and to compare the laparoscopic and thoracoscopic approaches. METHODS: Using MIS procedures, 30 patients (16 boys and 14 girls) from nine centers underwent surgery for CDH within the first month of life, 26 before day 5. Only one patient had associated malformations. There were 10 preterm patients (32-36 weeks of gestational age). Their weight at birth ranged from 1,800 to 3,800 g, with three patients weighing less than 2,600 g. Of the 30 patients, 18 were intubated at birth. RESULTS: The MIS procedures were performed in 18 cases by a thoracoscopic approach and in 12 cases by a laparoscopic approach. No severe complication was observed. For 20 patients, reduction of the intrathoracic contents was achieved easily with 15 thoracoscopies and 5 laparoscopies. In six cases, the reduction was difficult, proving to be impossible for the four remaining patients: one treated with thoracoscopy and three with laparoscopy. The reasons for the inability to reduce the thoracic contents were difficulty of liver mobilization (1 left CDH and 2 right CDH) and the presence of a dilated stomach in the thorax. Reductions were easier for cases of wide diaphragmatic defects using thoracoscopy. There were 10 conversions (5 laparoscopies and 5 thoracoscopies). The reported reasons for conversion were inability to reduce (n = 4), need for a patch (n = 5), lack of adequate vision (n = 4), narrow working space (n = 1), associated bowel malrotation (n = 1), and an anesthetic problem (n = 1). Five defects were too large for direct closure and had to be closed with a patch. Four required conversion, with one performed through video-assisted thoracic surgery. The recurrences were detected after two primer thoracoscopic closures, one of which was managed by successful reoperation using thoracoscopy. CONCLUSIONS: In the neonatal period, CDH can be safely closed using MIS procedures. The overall success rate in this study was 67%. The indication for MIS is not related to weeks of gestational age, to weight at birth (if >2,600 g), or to the extent of the immediate neonatal care. Patients with no associated anomaly who are hemodynamically stabilized can benefit from MIS procedures. Reduction of the herniated organs is easier using thoracoscopy. Right CDH, liver lobe herniation, and the need for a patch closure are the most frequent reasons for conversion.
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We investigate the interface between trade and invasive species (IS) risk, focusing on the existing tariff escalation in agro-forestry product markets and its implication for IS risk. Tariff escalation in processed agro-forestry products exacerbates the risk of IS by biasing trade flows toward increased trade of primary commodity flows and against processed-product trade. We show that reducing tariff escalation by lowering the tariff on processed goods increases allocative efficiency and reduces the IS externality, a win-win situation. We also identify policy menus for trade reforms involving tariffs on both raw input and processed goods, leading to winwin situations.
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This study reports the isolation and polymorphism characterization of four plastid indels and six nuclear microsatellite loci in the invasive plant Heracleum mantegazzianum. These markers were tested in 27 individuals from two distant H. mantegazzianum populations. Plastid indels revealed the presence of five chlorotypes while five nuclear microsatellite loci rendered polymorphism. Applications of these markers include population genetics and phylogeography of H. mantegazzianum. A very good transferability of markers to Heracleum sphondylium was demonstrated.
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The WHO classification of breast tumors distinguishes, besides invasive breast cancer 'of no special type' (former invasive ductal carcinoma, representing 60-70% of all breast cancers), 30 special types, of which invasive lobular carcinoma (ILC) is the most common (5-15%). We review the literature on (i) the specificity and heterogeneity of ILC biology as documented by various analytical techniques, including the results of molecular testing for risk of recurrence; (ii) the impact of lobular histology on prediction of prognosis and effect of systemic therapies in patients. Though it is generally admitted that ILC has a better prognosis than IDC, is endocrine responsive, and responds poorly to chemotherapy, currently available data do not unanimously support these assumptions. This review demonstrates some lack of specific data and a need for improving clinical research design to allow oncologists to make informed systemic therapy decisions in patients with ILC. Importantly, future studies should compare various endpoints in ILC breast cancer patients among the group of hormonosensitive breast cancer.
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Inorganic phosphate (Pi) and zinc (Zn) are two essential nutrients for plant growth. In soils, these two minerals are either present in low amounts or are poorly available to plants. Consequently, worldwide agriculture has become dependent on external sources of Pi and Zn fertilizers to increase crop yields. However, this strategy is neither economically nor ecologically sustainable in the long term, particularly for Pi, which is a non-renewable resource. To date, research has emphasized the analysis of mineral nutrition considering each nutrient individually, and showed that Pi and Zn homeostasis is highly regulated in a complex process. Interestingly, numerous observations point to an unexpected interconnection between the homeostasis of the two nutrients. Nevertheless, despite their fundamental importance, the molecular bases and biological significance of these interactions remain largely unknown. Such interconnections can account for shortcomings of current agronomic models that typically focus on improving the assimilation of individual elements. Here, current knowledge on the regulation of the transport and signalling of Pi and Zn individually is reviewed, and then insights are provided on the recent progress made towards a better understanding of the Zn-Pi homeostasis interaction in plants.
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Invasive opportunistic fungal diseases (IFDs) are important causes of morbidity and mortality in paediatric patients with cancer and those who have had an allogeneic haemopoietic stem-cell transplantation (HSCT). Apart from differences in underlying disorders and comorbidities relative to those of adults, IFDs in infants, children, and adolescents are unique with respect to their epidemiology, the usefulness of diagnostic methods, the pharmacology and dosing of antifungal agents, and the absence of interventional phase 3 clinical trials for guidance of evidence-based decisions. To better define the state of knowledge on IFDs in paediatric patients with cancer and allogeneic HSCT and to improve IFD diagnosis, prevention, and management, the Fourth European Conference on Infections in Leukaemia (ECIL-4) in 2011 convened a group that reviewed the scientific literature on IFDs and graded the available quality of evidence according to the Infectious Diseases Society of America grading system. The final considerations and recommendations of the group are summarised in this manuscript.
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Traits that mediate species interactions are evolutionarily shaped by biotic and abiotic drivers, yet we know relatively little about the relative importance of these factors. Herbivore pressure, along with resource availability and third-party' mutualists, are hypothesized to play a major role in the evolution of plant defence traits. Here, we used the model system Plantago lanceolata, which grows along steep elevation gradients in the Swiss Alps, to investigate the effect of elevation, herbivore pressure, mycorrhizal inoculation and temperature on plant resistance. Over a 1200 m elevation gradient, the levels of herbivory and iridoid glycosides (IGs) declined with increasing elevation. By planting seedlings at three different elevations, we further showed that both low-elevation growing conditions and mycorrhizal inoculation resulted in increased plant resistance to herbivores. Finally, using a temperature-controlled experiment comparing high- and low-elevation ecotypes, we showed that high-elevation ecotypes are less resistant to herbivory, and that lower temperatures impair IGs deployment after herbivore attack. We thus propose that both lower herbivore pressure, and colder temperatures relax the defense syndrome of high elevation plants.
What is "clinical data"? Why and how can they be collected during field surveys on medicinal plants?
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ETHNOPHARMACOLOGICAL RELEVANCE: "Reverse pharmacology", also called "bedside-to-bench" or "field to pharmacy" approach, is a research process starting with documentation of clinical outcome as observed by patients with different therapeutic regimens. The treatment most significantly associated with cure is selected for future studies: first, clinical safety and efficacy; then in vivo and vitro studies. Some clinical data, i.e. details on patient status and progress, can be collected during ethnobotanical surveys; they will help clinical researchers and, once effectiveness and safety are established, will also help users of traditional medicine make safer and more effective choices. To gather clinical data successfully, ethnopharmacologists need to be backed by an appropriate team of specialists in medicine and epidemiology. Ethnopharmacologists can also gather important data on traditional medicine safety. MATERIALS AND METHODS: The first step is to create a consensus on the meaning of "clinical data", their interest and importance. An understanding of why "a cure is not a proof of effectiveness" is a starting point to avoid faulty interpretation of the clinical observations. RESULTS: Experience showed that, with the "bedside-to-bench" approach, a treatment derived from traditional recipe can be scientifically validated (in terms of safety and effectiveness) with a cost of less than a million euros, thus providing an end-product that is affordable, available and sustainable. CONCLUSIONS: With rigorous clinical study results, medicinal plant users gain the possibility to refine heath strategies. The field surveyor may gain a better relationship with the population, once she/he is seen as bringing information useful for the quality of care in the community.
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We analyze the linkage between protectionism and invasive species (IS) hazard in the context of two-way trade and multilateral trade integration, two major features of real-world agricultural trade. Multilateral integration includes the joint reduction of tariffs and trade costs among trading partners. Multilateral trade integration is more likely to increase damages from IS than predicted by unilateral trade opening under the classic Heckscher-Ohlin-Samuelson (HOS) framework because domestic production (the base susceptible to damages) is likely to increase with expanding export markets. A country integrating its trade with a partner characterized by relatively higher tariff and trade costs is also more likely to experience increased IS damages via expanded domestic production for the same reason. We illustrate our analytical results with a stylized model of the world wheat market.
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Aim: We asked whether myocardial flow reserve (MFR) by Rb-82 cardiac PET improve the selection of patients eligible for invasive coronary angiography (ICA). Material and Methods: We enrolled 26 consecutive patients with suspected or known coronary artery disease who performed dynamic Rb-82 PET/CT and (ICA) within 60 days; 4 patients who underwent revascularization or had any cardiovascular events between PET and ICA were excluded. Myocardial blood flow at rest (rMBF), at stress with adenosine (sMBF) and myocardial flow reserve (MFR=sMBF/rMBF) were estimated using the 1-compartment Lortie model (FlowQuant) for each coronary arteries territories. Stenosis severity was assessed using computer-based automated edge detection (QCA). MFR was divided in 3 groups: G1:MFR<1.5, G2:1.5≤MFR<2 and G3:2≤MFR. Stenosis severity was graded as non-significant (<50% or FFR ≥0.8), intermediate (50%≤stenosis<70%) and severe (≥70%). Correlation between MFR and percentage of stenosis were assessed using a non-parametric Spearman test. Results: In G1 (44 vessels), 17 vessels (39%) had a severe stenosis, 11 (25%) an intermediate one, and 16 (36%) no significant stenosis. In G2 (13 vessels), 2 (15%) vessels presented a severe stenosis, 7 (54%) an intermediate one, and 4 (31%) no significant stenosis. In G3 (9 vessels), 0 vessel presented a severe stenosis, 1 (11%) an intermediate one, and 8 (89%) no significant stenosis. Of note, among 11 patients with 3-vessel low MFR<1.5 (G1), 9/11 (82%) had at least one severe stenosis and 2/11 (18%) had at least one intermediate stenosis. There was a significant inverse correlation between stenosis severity and MFR among all 66 territories analyzed (rho= -0.38, p=0.002). Conclusion: Patients with MFR>2 could avoid ICA. Low MFR (G1, G2) on a vessel-based analysis seems to be a poor predictor of severe stenosis severity. Patients with 3-vessel low MFR would benefit from ICA as they are likely to present a significant stenosis in at least one vessel.
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Wounded leaves communicate their damage status to one another through a poorly understood process of long-distance signalling. This stimulates the distal production of jasmonates, potent regulators of defence responses. Using non-invasive electrodes we mapped surface potential changes in Arabidopsis thaliana after wounding leaf eight and found that membrane depolarizations correlated with jasmonate signalling domains in undamaged leaves. Furthermore, current injection elicited jasmonoyl-isoleucine accumulation, resulting in a transcriptome enriched in RNAs encoding key jasmonate signalling regulators. From among 34 screened membrane protein mutant lines, mutations in several clade 3 GLUTAMATE RECEPTOR-LIKE genes (GLRs 3.2, 3.3 and 3.6) attenuated wound-induced surface potential changes. Jasmonate-response gene expression in leaves distal to wounds was reduced in a glr3.3 glr3.6 double mutant. This work provides a genetic basis for investigating mechanisms of long-distance wound signalling in plants and indicates that plant genes related to those important for synaptic activity in animals function in organ-to-organ wound signalling.
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Objective To explore beliefs, values and practices related to the use of medicinal plants among low-income black families. Method The research method was ethnography and the participant observation process was done in a low-income community in the peripheral area of the City of São Paulo. Twenty black women were interviewed. Results Two cultural sub-themes, I do use medicines that I learned to make with my mother and with religious practitioners to care for diseases and Home medicines are to treat problems that are not serious, and the cultural theme I do use home medicines to treat simple diseases because I always have them at my disposal, they are free and I don’t need a medical prescription represent beliefs, values, and practices related to the use of medicinal plants among low-income black families. Conclusion The development of such practices, which can hide ethnic and social vulnerability, reveals the resilience of low-income black women in the process of confronting problems during the health-illness process.
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Mountain ranges are biodiversity hotspots worldwide and provide refuge to many organisms under contemporary climate change. Gathering field information on mountain biodiversity over time is of primary importance to understand the response of biotic communities to climate changes. For plants, several long-term observation sites and networks of mountain biodiversity are emerging worldwide to gather field data and monitor altitudinal range shifts and community composition changes under contemporary climate change. Most of these monitoring sites, however, focus on alpine ecosystems and mountain summits, such as the global observation research initiative in alpine environments (GLORIA). Here we describe the Alps Vegetation Database, a comprehensive community level archive (GIVD ID EU-00-014) which aims at compiling all available geo-referenced vegetation plots from lowland forests to alpine grasslands across the greatest mountain range in Europe: the Alps. This research initiative was funded between 2008 and 2011 by the Danish Council for Independent Research and was part of a larger project to compare cross-scale plant community structure between the Alps and the Scandes. The Alps Vegetation Database currently harbours 35,731 geo-referenced vegetation plots and 5,023 valid taxa across Mediterranean, temperate and alpine environments. The data are mainly used by the main contributors of the Alps Vegetation Database in an ecoinformatics approach to test hypotheses related to plant macroecology and biogeography, but external proposals for joint collaborations are welcome.