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1.
As part of an ongoing research program aiming at monitoring molecular changes in the tissues and metabolite trafficking in the hydrosphere of algae subjected to chemical stresses, we are discussing the various analytical techniques that have been employed to characterize, and sometimes to quantity these metabolites. High-field multinuclear and solid-state nuclear magnetic resonance (NMR) spectroscopies are powerful tools for metabolite characterization from extracts and in vivo, but quantification and kinetic aspects show some limitations. Modern MS (mass spectrometry) is extremely useful for fingerprinting samples against databases and when dealing with very low concentrations of metabolites, the limitations being set by the type of chromatographic separation and mode of detection coupled with the mass spectrometer. Regarding chemical communication, optimization in terms of resolution and efficiency of hydrosphere chemical analysis can theoretically be achieved in a system which integrates (i) a multiparametric incubation chamber, (ii) a gasphase or a liquid-phase separation system and (iii) mass spectrometer(s) equipped with one or two detectors responding to the analytical and quantitative needs. This text reviews some of the techniques that have been employed in various types of plant metabolic studies, which may serve as a basis towards an integrative analytical strategy directly applicable to the metabolomics of selected marine macrophytes.  相似文献   

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Anaerobic waste digestion in Germany – Status and recent developments   总被引:1,自引:0,他引:1  
Weiland P 《Biodegradation》2000,11(6):415-421
Anaerobic treatment processes are especially suited for the utilization of wet organic wastes from agriculture and industry as well as for the organic part of source-separated household wastes. The anaerobic degradation is a very cost-effective method for treating biogenic wastes because the formed biogas can be used for heat and electricity production and the digester residues can be recycled to agriculture as a secondary fertilizer. The anaerobic technology will be used today also for the common treatment of wastes together with renewable energy crops in order to reduce the CO2-emissions according the Kyoto protocol. Various process types are applied in Germany which differ in material, reaction conditions and in the form of the used reactor systems. The widespread introduction of anaerobic digestion in Germany has shown that biogenic organic wastes are a valuable source for energy and nutrients. Anaerobic waste treatment is done today in approx. 850 biogas plants on small farm scale as well as on large industrial scale with the best beneficial and economic outcome. Due to some new environmental protection acts which promote the recycling of wastes and their utilization for renewable energy formation it can be expected that several hundreds new biogas plants will be built per year in Germany. For using the synergetic effects of a combined fermentation of wastes and energy crops new process types must be developed in order to optimize the substrate combinations and the process conditions for maximum biodegradation.  相似文献   

3.
The therapeutic potential of interfering with dysregulated proteins by inducing its selective degradation has been pursued using different mechanisms. In the present article, we review representative examples of monovalent protein-degraders that, contrary to the proteolysis targeting chimeras, achieve target degradation without displaying recognition motifs for the recruitment of E3 ubiquitin ligases. We also highlight new technologies and assays that may brought to bear on the discovery of common elements that could predict and enable the selective degradation of pathogenic targets by monovalent protein-degraders. The successful application of these methods would pave the way to the advancement of new drugs with unique efficacy and tolerability properties.  相似文献   

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Last summer we officially launched the Journal of Ethnobiology and Ethnomedicine, published by BioMedCentral, with the aim of establishing a serious, peer-reviewed, open-access online journal that focuses on the multidisciplinary, interdisciplinary, and transdisciplinary fields of ethnobiology and ethnomedicine, drawing on approaches and methods from both the social and biological sciences. The strong start vindicates the widely held belief that the journal responds to a real need within the research community. The success of the journal has been most gratifying. The steady influx of submissions of high scientific standards illustrates the strong demand for a dynamic, proactive, and open-minded scientific journal in these research areas. Our aim has been to dedicate JEE to the "scientific communities" worldwide, particularly those in the developing countries.  相似文献   

5.
Acute kidney injury is common in patients with liver disease and associated with significant morbidity and mortality. Besides bacterial infections, fluid loss, and use of nephrotoxic drugs AKI in liver disease may be triggered by tubular toxicity of cholephiles. Cholemic nephropathy, also known as bile cast nephropathy, supposedly represents a widely underestimated but important cause of renal dysfunction in cholestasic or advanced liver diseases with jaundice. Cholemic nephropathy describes impaired renal function along with characteristic histomorphological changes consisting of intratubular cast formation and tubular epithelial cell injury directed towards distal nephron segments. The underlying pathophysiologic mechanisms are not entirely understood and clear defined diagnostic criteria are still missing.This review aims to summarize (i) the present knowledge on clinical and morphological characteristics of cholemic nephropathy, (ii) available preclinical models, (iii) potential pathomechanisms especially the potential role of bile acids, and (iv) future diagnostic and therapeutic strategies for cholemic nephropathy. This article is part of a Special Issue entitled: Cholangiocytes in Health and Disease edited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.  相似文献   

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Origins of Life and Evolution of Biospheres - Syntheses under shock in nitrogen bubbled samples of the water – formamide – bicarbonate – sodium hydroxide system at...  相似文献   

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Plant-associated microorganisms fulfill important functions for plant growth and health. Direct plant growth promotion by microbes is based on improved nutrient acquisition and hormonal stimulation. Diverse mechanisms are involved in the suppression of plant pathogens, which is often indirectly connected with plant growth. Whereas members of the bacterial genera Azospirillum and Rhizobium are well-studied examples for plant growth promotion, Bacillus, Pseudomonas, Serratia, Stenotrophomonas, and Streptomyces and the fungal genera Ampelomyces, Coniothyrium, and Trichoderma are model organisms to demonstrate influence on plant health. Based on these beneficial plant–microbe interactions, it is possible to develop microbial inoculants for use in agricultural biotechnology. Dependent on their mode of action and effects, these products can be used as biofertilizers, plant strengtheners, phytostimulators, and biopesticides. There is a strong growing market for microbial inoculants worldwide with an annual growth rate of approximately 10%. The use of genomic technologies leads to products with more predictable and consistent effects. The future success of the biological control industry will benefit from interdisciplinary research, e.g., on mass production, formulation, interactions, and signaling with the environment, as well as on innovative business management, product marketing, and education. Altogether, the use of microorganisms and the exploitation of beneficial plant–microbe interactions offer promising and environmentally friendly strategies for conventional and organic agriculture worldwide.  相似文献   

10.
This article emphasizes on the present urgent need to think in “Holistic Dimensions” to achieve a sustainable agro-ecosystem. In this respect, the complex network of dynamic interactions in the agro-ecosystem soil at spatiotemporal dimensions holds crucial importance. It reflects the inherent tendency of dynamic ecosystems to achieve a more efficient state successively through improved interactions. The short-sighted and inefficient agro-management during Green Revolution decades has been detrimental to these interactions in agricultural soils, which is widely evident by its boomerang effects (i.e. declining efficiency, productivity and multi-functionality). It jeopardized the internal regulation in our agro-ecosystem's functioning by erosion of efficiency building interactions among biotic and abiotic components. Therefore, a bottom-up as well as top-down approach in the soil management is required to restore and sustain the unaccounted but indispensible ecological subsidies for sustainable agriculture and development, globally. We propose a “commercial ecological agriculture” which should be an amalgamation of sustainable agricultural practices and supported by a progressive co-ordination among all the stakeholders via participatory learning and adaptation with time. It should be least-disturbing, resilience-building, resource (i.e. energy and nutrient) use efficient, site-specific, labor and skill-intensive, low-input, diversified and integrated, and intimately harmonized with nature. It may potentially provide us agricultural sustainability with time in real sense. It would be primarily based on management of interactions indirectly through identification of integrative variables as surrogate, which may help to achieve internal regulation or self-reliance in agroecosystems. Further, it would be helpful to eliminate the widening socio-economic divide and in mitigation of global change in environment (i.e. air, water and soil) and climate. Additionally, it would improve and restore the multifaceted potential of soil, thus quality and productivity, through improved internal regulation on resource-use efficiency.  相似文献   

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In a cohort study among 2751 members (71.5% females) of the German and Swiss RLS patient organizations changes in restless legs syndrome (RLS) severity over time was assessed and the impact on quality of life, sleep quality and depressive symptoms was analysed. A standard set of scales (RLS severity scale IRLS, SF-36, Pittsburgh Sleep Quality Index and the Centre for Epidemiologic Studies Depression Scale) in mailed questionnaires was repeatedly used to assess RLS severity and health status over time and a 7-day diary once to assess short-term variations. A clinically relevant change of the RLS severity was defined by a change of at least 5 points on the IRLS scale. During 36 months follow-up minimal improvement of RLS severity between assessments was observed. Men consistently reported higher severity scores. RLS severity increased with age reaching a plateau in the age group 45–54 years. During 3 years 60.2% of the participants had no relevant (±5 points) change in RLS severity. RLS worsening was significantly related to an increase in depressive symptoms and a decrease in sleep quality and quality of life. The short-term variation showed distinctive circadian patterns with rhythm magnitudes strongly related to RLS severity. The majority of participants had a stable course of severe RLS over three years. An increase in RLS severity was accompanied by a small to moderate negative, a decrease by a small positive influence on quality of life, depressive symptoms and sleep quality.  相似文献   

12.
Over the past few decades, a considerable attention has been focused on the microbial polyhydroxyalkanoates (PHAs) owing to its multifaceted properties, i.e. biodegradability, biocompatibility, non-toxicity and thermo-plasticity. This article presents a critical review of the foregoing research, current trends and future perspectives on the value added applications of PHAs in the biomedical, environmental and industrial domains of life.  相似文献   

13.
A critical assessment of the data recently put forward in favour of a ‘Mesolithic agriculture’ for Central and Northern Europe is presented. The archaeobotanical record is quite clear: hundreds of excavations of early Neolithic sites, whether from Linearbandkeramik or Trichterbecher (funnel beaker) settlements have produced remains of cultivated plants in large numbers. In contrast to this, all Mesolithic sites excavated so far have not revealed even one macroscopic find of crop plants. The ‘Mesolithic agriculture’ as assumed by several authors, is based solely on single pre-Neolithic pollen grains of the Cerealia-type that occur in pollen diagrams. It is shown that absolute distinction of pollen from wild grasses and cereals is impossible. There is a certain overlapping of both types that must not be neglected. Because of the large pollen sums in modern pollen diagrams, even very scarce grains of Cerealia-type pollen are encountered. Most of these single pre-Neolithic grains must derive from native wild grasses, while others come by long-distance transport etc. Another important feature is the scattered occurrence of Cerealia-type pollen grains from the early Holocene (or even Pleistocene) to the start of the Neolithic. They do not occur in synchronous phases and even in neighbouring sites they do not agree in age. As long as there are no well-dated macro-remains of crop plants of pre-Neolithic age, there is no evidence of Mesolithic agriculture.  相似文献   

14.
2-Azahypoxanthine (AHX, 1) and imidazole-4-carboxamide (ICA, 2) were isolated from a fairy-ring forming fungus Lepista sordida. AHX was converted into a metabolite, 2-aza-8-oxohypoxanthine (AOH, 3), in plants. Afterward, it turned out that these three compounds, fairy chemicals (FSc), endogenously exist in plants and are biosynthesized via a new purine metabolic pathway. Furthermore, FCs increased the yields of rice, wheat and other crops in the filled experiments.  相似文献   

15.

Background

Little is known about how parental socioeconomic status affects offspring asthma risk in the general population, or its relation to healthcare and medication use among diagnosed children.

Methods

This register-based cohort study included 211,520 children born between April 2006 and December 2008 followed until December 2010. Asthma diagnoses were retrieved from the National Patient Register, and dispensed asthma medications from the Prescribed Drug Register. Parental socioeconomic status (income and education) were retrieved from Statistics Sweden. The associations between parental socioeconomic status and outcomes were estimated by Cox proportional hazard regression.

Results

Compared to the highest parental income level, children exposed to all other levels had increased risk of asthma during their first year of life (e.g. hazard ratio, HR 1.19, 95% confidence interval, CI 1.09–1.31 for diagnosis and HR 1.17, 95% CI 1.08–1.26 for medications for the lowest quintile) and the risk was decreased after the first year, especially among children from the lowest parental income quintile (HR 0.84, 95% CI 0.77–0.92 for diagnosis, and HR 0.80, 95% CI 0.74–0.86 for medications). Further, compared to children with college-educated parents, those whose parents had lower education had increased risk of childhood asthma regardless of age. Children with the lowest parental education had increased risk of an inpatient (HR 2.07, 95% CI 1.61–2.65) and outpatient (HR 1.32, 95% CI 1.18–1.47) asthma diagnosis. Among diagnosed children, those from families with lower education used fewer controller medications than those whose parents were college graduates.

Conclusions

Our findings indicate an age-varying association between parental income and childhood asthma and consistent inverse association regardless of age between parental education and asthma incidence, dispensed controller medications and inpatient care which should be further investigated and remedied.  相似文献   

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Water is vital for plant growth, development and productivity. Permanent or temporary water deficit stress limits the growth and distribution of natural and artificial vegetation and the performance of cultivated plants (crops) more than any other environmental factor. Productive and sustainable agriculture necessitates growing plants (crops) in arid and semiarid regions with less input of precious resources such as fresh water. For a better understanding and rapid improvement of soil–water stress tolerance in these regions, especially in the water-wind eroded crossing region, it is very important to link physiological and biochemical studies to molecular work in genetically tractable model plants and important native plants, and further extending them to practical ecological restoration and efficient crop production. Although basic studies and practices aimed at improving soil water stress resistance and plant water use efficiency have been carried out for many years, the mechanisms involved at different scales are still not clear. Further understanding and manipulating soil–plant water relationships and soil–water stress tolerance at the scales of ecology, physiology and molecular biology can significantly improve plant productivity and environmental quality. Currently, post-genomics and metabolomics are very important in exploring anti-drought gene resources in various life forms, but modern agriculturally sustainable development must be combined with plant physiological measures in the field, on the basis of which post-genomics and metabolomics have further practical prospects. In this review, we discuss physiological and molecular insights and effects in basic plant metabolism, drought tolerance strategies under drought conditions in higher plants for sustainable agriculture and ecoenvironments in arid and semiarid areas of the world. We conclude that biological measures are the bases for the solutions to the issues relating to the different types of sustainable development.  相似文献   

18.
Neolithic and Bronze Age topsoil relicts revealed enhanced extractable phosphorus (P) and plant available inorganic P fractions, thus raising the question whether there was targeted soil amelioration in prehistoric times. This study aimed (i) at assessing the overall nutrient status and the soil organic matter content of these arable topsoil relicts, and (ii) at tracing ancient soil fertilizing practices by respective stable isotope and biomarker analyses. Prehistoric arable topsoils were preserved in archaeological pit fillings, whereas adjacent subsoils served as controls. One Early Weichselian humic zone represented the soil status before the introduction of agriculture. Recent topsoils served as an additional reference. The applied multi-proxy approach comprised total P and micronutrient contents, stable N isotope ratios, amino acid, steroid, and black carbon analyses as well as soil color measurements. Total contents of P and selected micronutrients (I, Cu, Mn, Mo, Se, Zn) of the arable soil relicts were above the limits for which nutrient deficiencies could be assumed. All pit fillings exhibited elevated δ15N values close to those of recent topsoils (δ15N>6 to 7‰), giving first hints for prehistoric organic N-input. Ancient legume cultivation as a potential source for N input could not be verified by means of amino acid analysis. In contrast, bile acids as markers for faecal input exhibited larger concentrations in the pit fillings compared with the reference and control soils indicating faeces (i.e. manure) input to Neolithic arable topsoils. Also black carbon contents were elevated, amounting up to 38% of soil organic carbon, therewith explaining the dark soil color in the pit fillings and pointing to inputs of burned biomass. The combination of different geochemical analyses revealed a sufficient nutrient status of prehistoric arable soils, as well as signs of amelioration (inputs of organic material like charcoal and faeces-containing manure).  相似文献   

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