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1.
Current issues in research on health effects by polyphenols are addressed. As to the cardiovascular system, flow-mediated dilation (FMD), a functional biomarker, can be used as surrogate marker for cardiovascular risk. Acute short-term effects peaking at 2 h after ingestion of polyphenol-rich food items are distinguished from longer-term effects over days and weeks. The role of polyphenol metabolites as bioactives is presented, underlining that specific target enzymes such as NADPH oxidases or lipoxygenases provide a basis for molecular action of polyphenols, rather than unspecific direct antioxidant effects. Cautionary words are given for the use of non-compositional assays of ‘total antioxidant capacity’ (TAC) in blood plasma. Enhanced interest emerges for polyphenols in the gastrointestinal tract. Recommendations for health professionals and the public are summarized, as well as prospects and challenges for future research.  相似文献   

2.
Optical and spectroscopic methods for biofilmexamination and monitoring are reviewed.Biofilm examination techniques includemicroscopic methods, coupled with imageanalysis and with oligonucleotide ribosomal RNAprobing methods (fluorescence in situhybridization). Microscopic examinationtechniques are especially advantageous inextracting biofilm structural and architecturalparameters, as well as structure-functionrelationships of the biofilm microbialpopulation. Spectroscopic techniques are ableto elicit biofilm chemical and metabolicpatterns, as well as biofilm activity. They areof outstanding importance for on-line,non-invasive biofilm monitoring, especiallywhen coupled with chemometric algorithms forspectra calibration and pattern recognition.The paper emphasises the importance of thecombination of novel and established analyticaltechniques, as well as their integration withpowerful computational methods for theautomation of biofilm monitoring.  相似文献   

3.
Liquid and gaseous fuels from biotechnology: challenge and opportunities   总被引:3,自引:0,他引:3  
Abstract: This paper presents challenging opportunities for production of liquid and gaseous fuels by biotechnology. From the liquid fuels, ethyl alcohol production has been widely researched and implemented. The major obstacle for large scale production of ethanol for fuel is the cost, whereby the substrate represents one of the major cost components. Various scenarios will be presented for a critical assessment of cost distribution for production of ethanol from various substrates by conventional and high rate processes. The paper also focuses on recent advances in the research and application of biotechnological processes and methods for the production of liquid transportation fuels other than ethanol (other oxygenates; diesel fuel extenders and substitutes), as well as gaseous fuels (biogas, methane, reformed syngas). Potential uses of these biofuels are described, along with environmental concerns which accompany them. Emphasis is also put on microalgal lipids as diesel substitute and biogas/methane as a renewable alternative to natural gas. The capturing and use of landfill gases is also mentioned, as well as microbial coal liquefaction. Described is also the construction and performance of microbial fuel cells for the direct high-efficiency conversion of chemical fuel energy to electricity. Bacterial carbon dioxide recovery is briefly dealt with as an environmental issue associated with the use of fossil energy.  相似文献   

4.
Livestock and aquaculture production is under political and social pressure, especially in the European Union (EU), to decrease pollution and environmental damage arising due to animal agriculture. The EU has banned the use of antibiotics and other chemicals, which have been shown to be effective in promoting growth and reducing environment pollutants because of the risk caused to humans by chemical residues in food and by antibiotic resistance being passed on to human pathogens. As a result of this, scientists have intensified efforts in exploiting plants, plant extracts or natural plant compounds as potential natural alternatives for enhancing the livestock productivity. This paper discusses work on the effects of various phytochemicals and plant secondary metabolites in ruminant and fish species. The focus is on (i) plants such as Ananas comosus (pine apple), Momordica charantia (bitter gourd) and Azadirachta indica (neem) containing anthelmintic compounds and for their use for controlling internal parasites; (ii) plants containing polyphenols and their applications for protecting proteins from degradation in the rumen, increasing efficiency of microbial protein synthesis in rumen and decreasing methane emission; for using as antioxidants, antibacterial and antihelmintic agents; and for changing meat colour and for increasing n-3 fatty acids and conjugated linoleic acid in meat; (iii) saponin-rich plants such as quillaja, yucca and Sapindus saponaria for increasing the efficiency of rumen fermentation, decreasing methane emission and enhancing growth; for producing desired nutritional attributes such as lowering of cholesterol in monogastric animals; for increasing growth of fish (common carp and Nile tilapia) and for changing male to female ratio in tilapia; and for use as molluscicidal agents; (iv) Moringa oleifera leaves as a source of plant growth factor(s), antioxidants, beta-carotene, vitamin C, and various glucosinolates and their degraded products for possible use as antibacterial, antioxidant, anticarcinogenic and antipest agents; (v) Jatropha curcas toxic variety with high levels of various phytochemicals such as trypsin inhibitor, lectin, phytate and phorbol esters in seeds limiting the use of seed meal in fish and livestock diets; and the use of phorbol esters as bio-pesticidal agent; and (vi) lesser-known legumes such as Entada phaseoloides seeds containing high levels of trypsin inhibitor and saponins, Sesbania aculeate seeds rich in non-starch polysaccharides and Mucuna pruriens var. utilis seeds rich in l-3,4-dihydroxyphenylalanine and their potential as fish feed; Cassia fistula seeds as a source of antioxidants; and the use of Canavalia ensiformis, C. gladiata and C. virosa seeds containing high levels of trypsin inhinitor, lectins and canavanine. The paper also presents some challenges and future areas of work in this field.  相似文献   

5.
Until relatively recently, in countries such as the U.S.A. and U.K., individuals could only opt for “single race” categories with which they identified. However, in the 2000 decennial census, respondents in the U.S. were able to choose more than one racial category, while in 2001, a “Mixed” box (with further subcategories) was provided in the England and Wales census for the first time. But the very success of this racial project in these countries has spawned a number of questions for policy-makers and academics who theorize, enumerate and study the experiences of multiracial people. With demographic changes such as generational change, who counts as multiracial or mixed race? This question has yet to receive significant attention. Although mixing is becoming more commonplace, the question of who counts as multiracial is far from straightforward, especially as we look down the generational pipeline.  相似文献   

6.
Biological surfaces are multifunctional interfaces between the organisms and their environment. Properties such as the wettability and adhesion of particles are linked to the micro- and nanostructures of their surfaces. In this study, we used plant and artificial surfaces covered with wax crystals to develop a low-cost replication technique with high resolution. The technique is applicable for fragile surface structures, as demonstrated for three-dimensional wax crystals, and is fast to prevent shrinking of the biological material by water loss during the molding process. Thermal evaporation of octacosan-1-ol has been used to create microstructured surfaces with small platelets as templates for molding. Epoxy resin as filling material provided the smallest deviations from the original surface structures and can be used for replication of nanostructures as small as 4.5 nm. Contact angle measurements of leaves and their replicas show that this technique can be used to develop biomimetic surfaces with similar wettability as in the plant surfaces.  相似文献   

7.
A simple and safe procedure has been described for the preparation of short-chain aliphatic hydroxamic acids in quantities as large as 1 mole and as small as 0.01 mole. The procedure is equally suitable for the preparation of isotopically labeled hydroxamates, as has been demonstrated in the case of 1-14C-acetohydroxamic acid and 3H-acetohydroxamic acid. Some physical and chemical characteristics, including infrared spectra of formo-, aceto-, propiono-, and isobutyro-hydroxamic acids prepared by this method have been described.  相似文献   

8.
Summary Progeny testing and selection of forage grasses by means of growing half-sib (HS) families from openpollination and polycross have been considered from theoretical and practical points of view. Special attention has been paid to the genetic variation within half-sib families, which is expected to be large as compared to the genetic variation between families. Based on observations of individual plants within plots, the environmental component of the variation is expected to be large and nonestimatable. The results of an experiment in meadow fescue (Festuca pratensis Huds.) are presented. In this experiment, randomly selected individual plants within HS families were cloned and laid out in randomized blocks. For the characters observed (earliness and raw matter yield) no significant variance component for dominance was found. The highly significant additive component estimated for earliness, as well as for yield, after each of three cuts and in total were about three times as large within as between families, as expected from the theoretical considerations. The estimated response to selection was much higher for a combination of between- and within-family selection as compared to free clone or family mean selection alone. It is suggested that a program for progeny testing and selection in a base population of perennial forage grasses should start with an experiment in which a large number of randomly selected parental clones and a fixed number of clones from each of the half-sib families derived from the mother genotypes are grown simultaneously. The selected clones within superior families could later on be further cloned, placed in a polycross field, and the new HS-families could be sown in ordinary field trials at various locations for further selection.  相似文献   

9.
Efforts to improve the clinical management of several cancers include finding better methods for the quantitative and qualitative analysis of circulating tumor cells (CTCs). However, detection and isolation of CTCs from the blood circulation is not a trivial task given their scarcity and the lack of reliable markers to identify these cells. With a variety of emerging technologies, a thorough review of the exploited principles and techniques as well as the trends observed in the development of these technologies can assist researchers to recognize the potential improvements and alternative approaches. To help better understand the related biological concepts, a simplified framework explaining cancer formation and its spread to other organs as well as how CTCs contribute to this process has been presented first. Then, based on their basic working-principles, the existing methods for detection and isolation of CTCs have been classified and reviewed as nucleic acid-based, physical properties-based and antibody-based methods. The review of literature suggests that antibody-based methods, particularly in conjunction with a microfluidic lab-on-a-chip setting, offer the highest overall performance for detection and isolation of CTCs. Further biological and engineering-related research is required to improve the existing methods. These include finding more specific markers for CTCs as well as enhancing the throughput, sensitivity, and analytic functionality of current devices.  相似文献   

10.
Synthesis and applications of cyclopeptides and depsipeptides   总被引:1,自引:0,他引:1  
A solid phase protocol has been devised for the synthesis of linearprecursors to cyclic depsipeptide analogues of dolastatin D.t-Butyldimethylsilyl groups were used for hydroxy group protection, withdeprotection being carried out by t-butyl ammonium fluoride. HATU and PyBropwere successful in coupling highly hindered residues and in depside bondformation. Cyclic peptide analogues, cyclo[Arg-Gly-Asp-d-Phe-Lys(or Tyr)]have been synthesised and modified for use as carrier molecules for thetransport of radio isotopes (111In and 125I)into blood platelets as prototypes for medical imaging.  相似文献   

11.
Elevation of the level of intracellular reactive oxygen species (ROS) has immense implication in the biological system. On the one hand, ROS promote the signaling cascades for the maintenance of normal physiological functions, the phenomenon referred to as redox biology, and on the other hand increased ROS can cause damages to the cellular macromolecules as well as genetic material, the process known as oxidative stress. Oxidative stress acts as an etiological factor for wide varieties of pathologies, cancer being one of them. ROS is regarded as a “double-edged sword” with respect to oncogenesis. It can suppress as well as promote the malignant progression depending on the type of signaling pathway it uses. Moreover, the attribution of ROS in promoting phenotypic plasticity as well as acquisition of stemness during neoplasia has become a wide area of research. The current review discussed all the aspects of ROS in the perspective of tumor biology with special reference to epithelial-mesenchymal transition (EMT) and cancer stem cells.  相似文献   

12.
For many years, the role of internal radiotherapy has remained limited to certain historical indications such as thyroid cancers or to academic medical research. However, the recent recognition of theranostics and targeted therapies as one of the cornerstones of the modern concept of personalized medicine, has participated in the promotion of new developments for beta and alpha radiotherapy. In this paper, we will review the emerging radionuclides, radiopharmaceutical developments and advances, as well as the clinical successes that have been made in past few years. The results obtained, for some very promising, could herald in a new era for nuclear medicine. However, as presented in this review, in order to fully exploit its potential, and not to remain static as a promising or emerging therapy, the entire field of nuclear medicine must invest in the implementation of well-designed prospective and comparative studies for targeted radiotherapy.  相似文献   

13.
The essentiality of vitamin D for normal growth and development has been recognized for over 80 years, and vitamin D fortification programs have been in place in the United States for more than 70 years. Despite the above, vitamin D deficiency continues to be a common finding in certain population groups. Vitamin D deficiency has been suggested as a potential risk factor for the development of preeclampsia, and vitamin D deficiency during infancy and early childhood is associated with an increased risk for numerous skeletal disorders, as well as immunological and vascular abnormalities. Vitamin D deficiency can occur through multiple mechanisms including the consumption of diets low in this vitamin and inadequate exposure to environmental ultraviolet B rays. The potential value of vitamin D supplementation in high‐risk pregnancies and during infancy and early childhood is discussed. Currently, there is vigorous debate concerning what constitutes appropriate vitamin D intakes during early development as exemplified by differing recommendations from the Institute of Medicine Dietary Reference Intake report and recent recommendations by the Endocrine Society. As is discussed, a major issue that needs to be resolved is what key biological endpoint should be used when making vitamin D recommendations for the pregnant woman and her offspring. Birth Defects Research (Part C) 99:24–44, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

14.
Plants are important sources of food and plant products are essential for modern human life. Plants are increasingly gaining importance as drug and fuel resources, bioremediation tools and as tools for recombinant technology. Considering these applications, database infrastructure for plant model systems deserves much more attention. Study of plant biological pathways, the interconnection between these pathways and plant systems biology on the whole has in general lagged behind human systems biology. In this article we review plant pathway databases and the resources that are currently available. We lay out trends and challenges in the ongoing efforts to integrate plant pathway databases and the applications of database integration. We also discuss how progress in non-plant communities can serve as an example for the improvement of the plant pathway database landscape and thereby allow quantitative modeling of plant biosystems. We propose Good Database Practice as a possible model for collaboration and to ease future integration efforts.  相似文献   

15.
Solid tumors require blood vessels for growth and dissemination, and lymphatic vessels as additional conduits for metastatic spread. The identification of growth factor receptor pathways regulating angiogenesis has led to the clinical approval of the first antiangiogenic molecules targeted against the vascular endothelial growth factor (VEGF)-VEGF receptor (VEGFR)-2 pathway. However, in many cases resistance to anti-VEGF-VEGFR therapy occurs, and thus far the clinical benefit has been limited to only modest improvements in overall survival. Therefore, novel treatment modalities are required. Here, we discuss the members of the VEGF-VEGFR family as well as the angiopoietin growth factors and their Tie receptors as potential novel targets for antiangiogenic and antilymphangiogenic therapies.  相似文献   

16.
Microdialysis sampling has become an important method for the continuous monitoring from an in vivo environment. This technique has been used to monitor many endogenous molecules, such as neurotransmitters, as well as exogenous species such as drug substances. Microdialysis samples have traditionally been analyzed by liquid chromatographic (LC) methods to gain resolution and quantification of the molecules of interest. However, LC separations have a relatively large injection volume requirement which, as a consequence, increases microdialysis sampling times. Capillary electrophoresis (CE), with its very small sample volume requirements and high resolving power, has therefore gained popularity as an alternative to LC. Reviewed here are many of the technologies currently available for CE and examples of how this technique has been effectively applied to the analysis of microdialysis samples.  相似文献   

17.
Baker E  Michel E 《ZooKeys》2011,(150):167-176
The International Commission of Zoological Nomenclature has used the Scratchpads platform (currently being developed and maintained by ViBRANT) as the foundation for its redesigned website and as a platform for engaging with its users. The existing Scratchpad tools, with extensions to provide additional functions, have allowed for a major transformation in presentation of linked nomenclatural tools. Continued development of the new website will act as a springboard for the ICZN to participate more fully in the wider community of biodiversity informatics.  相似文献   

18.
Neutrophils and immunity: challenges and opportunities   总被引:1,自引:0,他引:1  
Scientists who study neutrophils often have backgrounds in cell biology, biochemistry, haematology, rheumatology or infectious disease. Paradoxically, immunologists seem to have a harder time incorporating these host-defence cells into the framework of their discipline. The recent literature discussed here indicates that it is appropriate for immunologists to take as much interest in neutrophils as in their lymphohaematopoietic cousins with smooth nuclei. Neutrophils inform and shape immune responses, contribute to the repair of tissue as well as its breakdown, use killing mechanisms that enrich our concepts of specificity, and offer exciting opportunities for the treatment of neoplastic, autoinflammatory and autoimmune disorders.  相似文献   

19.
There are three native Portuguese horse breeds: Lusitano, Sorraia and Garrano. This study compares diversity patterns of 17 protein and 12 microsatellite markers in these three as well as 30 other breeds to infer relationships among the breeds and to compare levels of polymorphism of these breeds for use in conservation efforts. The Garrano and the Lusitano showed a high level of genetic diversity, similar to that observed for most of the other analysed breeds, while the Sorraia and Friesian breeds showed low levels of variation for both genetic marker types. The combined protein and microsatellite data produced a tree that fit historical records well and with greater confidence levels than those for either data set alone. The combined genetic diversity and relationship information provides important baseline data for future breed conservation efforts, especially for a critically endangered breed such as the Sorraia.  相似文献   

20.
《Anthrozo?s》2013,26(4):369-372
ABSTRACT

Although there is a substantial body of research on inter-human empathy and inter-animal empathy, there is a dearth of research comparing humans' empathic reactions to humans and animals. To address this issue, three experiments were conducted in which participants read a scenario about a human or animal abuse victim in need of medical attention, and indicated the degree of empathy they had on an emotional response scale. In Experiment 1, women had significantly more empathy for animals than for humans, whereas men tended to express more empathy for humans than for animals. In Experiment 2, adult women expressed the same degree of empathy for a child as for a puppy. Similarly, in Experiment 3, adult men and women expressed the same degree of empathy for a baby as for a puppy. Overall, results indicated that people feel at least as much empathy for animals as for humans. We suggest that an animal target elicits a great deal of empathy partly because it is perceived as not being responsible for having caused the need situation. Future research will show whether empathy for animals translates to prosocial behavior toward them as well.  相似文献   

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