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1.
Aphids (Hemiptera: Aphididae) are a group of phloemfeeding insects numbering more than 5 000 extant species(Favret, 2014a). Most species have complex life cycles that include both asexual (viviparous parthenogenesis)and sexual reproduction. They display a high degree of intraspecific polyphenism with multiple phenotypes froman identical genotype, and they have specialized associations with their host plants (Blackman & Eastop, 2000).Some aphid species are gall-makers and even have evolved sociality with division of labor (Aoki, 1977; Stern &Foster, 1996). Many aphid species are agricultural and forestry pests. They incur damage to plants and carryvector plant viruses (Blackman & Eastop, 2000). Due to their fascinating biological character and economic importance, aphids have long been popular animals for research in basic and applied biology, and are becominguseful research models for studying important questions in ecology and evolution, especially in the genomic era(Brisson & Stem, 2006; Huang & Qiao, 2006; Srinivasan & Brisson, 2012).  相似文献   

2.
Leukocyte rolling and adhesion are complex physiological processes that have received a great deal of attention over the past decade. Significant increases in the knowledge base related to how leukocytes adhere in shear flows have occurred as a result of the development of novel experimental and computational techniques. Micro- and nano-fabrication techniques have enabled the development of novel flow devices for studying leukocyte adhesion in simple and complex geometries. Improvements in computer technology have enabled simulations of complex flow processes to be developed. As a result of these advances in knowledge related to leukocyte adhesion, numerous novel devices have been developed that mimic the leukocyte rolling and adhesion process. Examples of these devices include cell separation and enrichment devices and targeted ultrasound contrast agents. Future advances related to leukocyte rolling and adhesion processes hold great promise for advancing our knowledge of disease processes as well as development of novel therapeutic devices.  相似文献   

3.
The aquatic ferns of the genus Azolla are nitrogen-fixing plants that have great potentials in agricultural production and environmental conservation. Azolla in many aspects is qualified to serve as a model organism for genomic studies because of its importance in agriculture, its unique position in plant evolution, its symbiotic relationship with the N2-fixing cyanobacterium, Anabaena azollae, and its moderate-sized genome. The goals of this genome project are not only to understand the biology of the Azolla genome to promote its applications in biological research and agriculture practice but also to gain critical insights about evolution of plant genomes. Together with the strategic and technical improvement as well as cost reduction of DNA sequencing, the deciphering of their genetic code is imminent.  相似文献   

4.
In recent years, research in life sciences has been remarkably revolutionized owing to the establishment, development and application of genome editing technologies. Genome editing has not only accelerated fundamental research but has also shown promising applications in agricultural breeding and therapy. In particular, the clustered, regularly interspaced, short palindromic repeat (CRISPR) technology has become an indispensable tool in molecular biology owing to its high efficacy and simplicity. Genome editing tools have also been established in silkworm (Bombyx mori), a model organism of Lepidoptera insects with high economic importance. This has remarkably improved the level and scope of silkworm research and could reveal new mechanisms or targets in basic entomology and pest management studies. In this review, we summarize the progress and potential of genome editing in silkworm and its applications in functional genomic studies for generating novel genetic materials.  相似文献   

5.
Forests have long been recognized as excellent model systems for studying insect ecology. The fact that many forests' ecosystems still function in a semi-natural state, with little influence from human disturbance, provides unique opportunities for understanding co-evolved community and population processes. Unfortunately the structural complexity of forests and the sheer size of trees often pose formidable problems when attempting to sample insects in forests. As such, any scientist embarking on a study of forest insect ecology would be well-advised to carefullv plan their sampling efforts.  相似文献   

6.
Plants can accumulate, constitutively and/or after induction, a wide variety of defense compounds in their tissues that confer resistance to herbivorous insects. The naturally occurring plant resistance gene pool can serve as an arsenal in pest management via transgenic approaches. As insect-plant interaction research rapidly advances, it has gradually become clear that the effects of plant defense compounds are determined not only by their toxicity toward target sites, but also by how insects respond to the challenge. Insect digestive tracts are not passive targets of plant defense, but often can adapt to dietary challenge and successfully deal with various plant toxins and anti-metabolites. This adaptive response has posed an obstacle to biotechnology-based pest control approaches, which underscores the importance of understanding insect adaptive mechanisms. Molecular studies on the impact of protease inhibitors on insect digestion have contributed significantly to our understanding of insect adaptation to plant defense. This review will focus on exposing how the insect responds to protease inhibitors by both qualitative and quantitative remodeling of their digestive proteases using the cowpea bruchid-soybean cysteine protease inhibitor N system.  相似文献   

7.
Insects are a group of arthropods and the largest group of animals on Earth,with over one million species described to date.Like other life forms,insects suffer from viruses that cause disease and death.Viruses that are pathogenic to beneficial insects cause dramatic economic losses on agriculture.In contrast,viruses that are pathogenic to insect pests can be exploited as attractive biological control agents.All of these factors have led to an explosion in the amount of research into insect viruses in recent years,generating impressive quantities of information on the molecular and cellular biology of these viruses.Due to the wide variety of insect viruses,a better understanding of these viruses will expand our overall knowledge of their virology.Here,we review studies of several newly discovered RNA insect viruses in China.  相似文献   

8.
<正>Plant behavioral actions have been one of the major topics of research in plant biology and agriculture. These actions from plants are determined by their instant structural and physical reactions to the circumstances(Bouwmeester et al.,2019). Upon sensing abiotic factors such as salinity, flooding,high temperature, drought, plants make suitable changes in their physiology and behavior to survive such harsh conditions. Likewise, the continuous attack by biotic stresses such as insects a...  相似文献   

9.
Recent regenerative medicine and tissue engineering strategies(using cells, scaffolds, medical devices and gene therapy) have led to fascinating progress of translation of basic research towards clinical applications. In the past decade, great deal of research has focused on developing various three dimensional(3D) organs, such as bone, skin, liver, kidney and ear,using such strategies in order to replace or regenerate damaged organs for the purpose of maintaining or restoring organs’ functions that may have been lost due to aging, accident or disease. The surface properties of a material or a device are key aspects in determining the success of the implant in biomedicine, as the majority of biological reactions in human body occur on surfaces or interfaces. Furthermore, it has been established in the literature that cell adhesion and proliferation are, to a great extent, influenced by the micro- and nanosurface characteristics of biomaterials and devices. In addition, it has been shown that the functions of stem cells, mesenchymal stem cells in particular, could be regulated through physical interaction with specific nanotopographical cues. Therefore, guided stem cell proliferation, differentiation and function are of great importance in the regeneration of 3D tissues and organs using tissue engineering strategies. This review will provide an update on the impact of nanotopography on mesenchymal stem cells for the purpose of developing laboratory-based 3D organs and tissues, as well as the most recent research and case studies on this topic.  相似文献   

10.
The relevance of retinal diseases, both in society’s economy and in the quality of people’s life who suffer with them, has made stem cell therapy an interesting topic forresearch. Embryonic stem cells(ESCs), induced pluripotent stem cells(i PSCs) and adipose derived mesenchymal stem cells(ADMSCs) are the focus in current endeavors as a source of different retinal cells, such as photoreceptors and retinal pigment epithelial cells. The aim is to apply them for cell replacement as an option for treating retinal diseases which so far are untreatable in their advanced stage. ESCs, despite the great potential for differentiation, have the dangerous risk of teratoma formation as well as ethical issues, which must be resolved before starting a clinical trial. i PSCs, like ESCs, are able to differentiate in to several types of retinal cells. However, the process to get them for personalized cell therapy has a high cost in terms of time and money. Researchers are working to resolve this since i PSCs seem to be a realistic option for treating retinal diseases. ADMSCs have the advantage that the procedures to obtain them are easier. Despite advancements in stem cell application, there are still several challenges that need to be overcome before transferring the research results to clinical application. This paper reviews recent research achievements of the applications of these three types of stem cells as well as clinical trials currently based on them.  相似文献   

11.
Sand dwelling Turbellaria from the Netherlands Delta area   总被引:2,自引:2,他引:0  
Sand dwelling Turbellaria from the Delta of the Rivers Rhine, Meuse and Scheldt have been investigated. Thirty-eight samples taken from littoral and sublittoral stations in the Grevelingen, Eastern and Western Scheldt have been analysed.Thirty-three species were recorded (Acoela were not considered); twenty-four of them are new for the area and seven new species are described.Density and diversity of Turbellaria were higher in the Eastern Scheldt than in the Western Scheldt or in the Lake Grevelingen. A maximum density of 82 ind./100 cm3 was noted. A tentative calculation on relative abundance of the representatives of the different Turbellaria orders is established. Proseriata seem to be dominant in the localities studied.Abbreviations acg : accessory glands - aco : accessory organ - ad : atrial diverticle - b : bursa - br : brain - cil : cilia - cm : circular muscle - cn : cnidosac - co : copulatory organ - cs : cuticular spines - css : cuticular stylet sheat - de : ejaculatory duct - di : ductus intervesicularis - ds : seminal duct - dsp : spermatic duct - en : enteron - fd : female duct - fp : femal pore - ga : genital atrium - gf : glands in female duct - gg : glands - gp : genital pore - hp : adhesive papillae - ivs : intra capsular seminal vesicle - lm : longitudinal muscle - m : mouth - mp : male pore - ov : ovary - p : proboscis - pg : proboscisglands - ph : pharynx - phg : pharyngial glands - r : retractor muscle - rh : rhabdites - rhg : rhabdite glands - rs : seminal receptacle - s : stylet - sta : statocyst - ut : uterus - t : testis - v : vagina - vg : prostate vesicle - vi : vitellary - vs : seminal vesicle  相似文献   

12.
Summary Molecular species profiles were determined for both phosphatidylcholine (PC) and phosphatidylethanolamine (PE) of mitochondrial and microsomal membrane fractions from liver tissue of thermally-acclimated rainbow trout,Salmo gairdneri. The predominant molecular species of PC were 16:0/22:6, 16:0/18:1, 16:0/20:3 and 16:0/22:5, whereas predominant molecular species of PE were 18:1/20:4, 14:0/16:0, 18:0/22:6 and 18:1/22:6. PE possessed short chain saturates (primarily 14:0/16:0) and monoenes (primarily 14:0/16:1) not present in PC and larger proportions of polyunsaturated (18:0/22:6, 18:0/22:5 and 18:1/22:6. and diunsaturated molecular species than PC. Differences between membrane fractions were most evident in warm (20°C)-acclimated trout. Mitochondria contained higher proportions of long-chain, polyunsaturated molecular species of PE, but less of the corresponding species of PC than other membrane fractions. Rankings based on unsaturation index were accordingly: mitochondria heavy microsomes>light microsomes for PE, but heavy microsomes>light microsomes>-mitochondria for PC. Mitochondria were notable for high proportions of diunsaturated molecular species of both phosphatides. Growth at cold temperatures (5°C) was generally associated with a replacement of shorter chain mono- and dienoic molecular species (16:0/18:1, 16:1/18:1, 14:0/16:2 and 18:1/18:1 in the case of PC and 14:0/16:1, 14:0/16:2 and 16:1/18:1 for PE), and occasionally saturates, with long-chain, polyunsaturated molecular species (for PC, C36–38: 16:0/22:6, 16:1/22:6, 16:0/20:3 and 16:0/20:5; for PE, C38–40: 18:1/20:4, 16:1/22:6, 18:0/20:5, 18:2/20:4, 18:0/22:5 and 18:0/22:6). However, compositions of mitochondrial PE and PC from heavy microsomes were not significantly influenced by acclimation temperature. The role of phospholipase A2, in addition to other metabolic processes, in mediating these changes is discussed.Abbreviations ACL average chain length - UI unsaturation index  相似文献   

13.
The specificity of human plasma lecithin-cholesterol acyltransferase for molecular species of phosphatidylcholine (PC) was studied by determining the molecular species composition of whole plasma before and after incubation at 37 degrees C. Since the disappearance of PC under the conditions employed is entirely due to the activity of lecithin-cholesterol acyltransferase, its specificity can be determined from the decrease in the concentration of each species after the reaction. The selectivity factor for each species was calculated by dividing its observed contribution by its concentration at zero time. The major species contributing to cholesterol esterification in whole plasma were 16:0-18:2 (46%), 18:0-18:2 (16%), 16:0-18:1 (15%), 16:0-20:4 (10%), 18:0-20:4 (5%) and 18:1-18:2 (5%). The specificity, as determined from the selectivity factors for whole plasma, was in the order: 16:0-18:2 greater than 18:1-18:2 greater than 16:0-18:1 greater than 18:0-18:2 greater than 16:0-22:6 greater than 18:0-20:4 greater than 16:0-20:4. The high-density lipoproteins (HDL) contained a significantly higher percentage of 16:0-20:4 and 18:0-20:4 and a lower percentage of 16:0-18:1 and 18:0-18:1 compared to the very-low and low-density lipoproteins. These differences disappeared after incubation of the plasma for 24 h. Using selectivity factors for HDL PCs only, the specificity of the enzyme was found to be in the order: 16:0-18:2 greater than 18:1-18:2 greater than 18:1-18:1 greater than 16:0-22:6 greater than 18:0-18:2 greater than 16:0-18:1 greater than 16:0-20:4. These results indicate that in native plasma, lecithin-cholesterol acyltransferase prefers 16:0 greater than 18:1 greater than 18:0 at the 1-position and 18:2 greater than 18:1 greater than 22:6 greater than 20:4 at the 2-position of PC.  相似文献   

14.
15.
From data obtained by differential scanning calorimetry phase diagrams were constructed, using a thermodynamically based fitting method. The following binary mixtures of phosphatidylcholines in water were studied: 14:0/14:0-glycerophosphocholine/16:0/16:0-glucerophosphocholine, 14:0/14:0-glycerophosphocholine/18:0/18:0-glycerophosphocholine, 12:0/12:0-glycerophosphocholine/16:0/16:0-glycerophosphocholine, 18:1t/18:1t-glycerophosphocholine/14:0/14:0-glycerophosphocholine and 18:1t/18:1t-glycerophosphocholine/16:0/16:0-glycerophosphocholine. A comparison is made of the present results with those obtained using probe techniques and the differences are discussed.  相似文献   

16.
Analyses of Pneumocystis Fatty Acids   总被引:2,自引:0,他引:2  
The major ester-linked fatty acids of the total lipids extracted from Pneumocystis carinii isolated from the lungs of corticosteroid-trcaicd rats were 16:0. 18:0, 18:1, 18:2 and 20:4. Others detected included 14:0, 16:1 and 22:4. The major sphingolipid fatty acids were 16:0, 18:0,22:0,24:0 and 24:1; others included 14:0, 18:1, 20:0, 23:0, 24:2 and 26:0. The total lipid fatty acid compositions of preparations from appropriate lung controls were similar to those of the organism.  相似文献   

17.
18.
The linear growth of Botrytis cinerea, Fusarium caeruleum and Phoma foveata in culture was reduced in the presence of vapour from any of the three isomers of tetrachloronitrobenzene. The isomers were fungistatic but not fungicidal.
Differences in activity were observed amongst the isomers. The 2:3:4:6 isomer was the most active against all three test fungi. 2:3:5:6-TCNB (tecnazene) was more active than 2:3:4:5-TCNB against Botrytis cinerea , but less active against Fusarium caeruleum and Phoma foveata . Two strains of Fusarium caeruleum resistant to the 2:3:5:6 isomer were not resistant to the other two isomers, although they were more resistant than their 2:3:5:6-TCNB sensitive parent strains.
Sporulation and sclerotial production by Botrytis cinerea were completely suppressed by 2:3:5:6-TCNB and 2:3:4:6-TCNB but not by the 2:3:4:5: isomer.  相似文献   

19.
Ovary maturation, oocyte differentiation, and embryonic development in shrimp are highly dependent on nutritional lipids taken up by female broodstocks. These lipids are important as energy sources as well as for cell signaling. In this study, we report on the compositions of major lipids, i.e. phosphatidylcholines (PCs), triacylglycerols (TAGs), and fatty acids (FAs), in the ovaries of the banana shrimp, Penaeus merguiensis, during ovarian maturation. Thin-layer chromatography analysis showed that the total PC and TAG signal intensities increased during ovarian maturation. Further, by using gas chromatography, we found that (1) FAs 14:0, 16:1, 18:1, 18:2, 20:1, and 22:6 proportionally increased as ovarian development progressed to more mature stages; (2) FAs 16:0, 18:0, 20:4, and 20:5 proportionally decreased; and (3) FAs 15:0, 17:0, and 20:2 remained unchanged. By using imaging mass spectrometry, we found that PC 16:0/16:1 and TAG 18:1/18:2/22:6 were detected in oocytes stages 1 and 2. PCs 16:1/20:4, 16:0/22:6, 18:3/22:6, 18:1/22:6, 20:5/22:6, and 22:6/22:6 and TAGs 16:0/16:1/18:3, 16:0/18:1/18:3, 16:0/18:1/18:1, and 16:0/18:2/22:6 were present in all stages of oocytes. In contrast, the PC- and TAG-associated FAs 20:4, 20:5, and 22:6 showed high signal intensities in stage 3 and 4 oocytes. These FAs may act as nutrition sources as well as signaling molecules for developing embryos and the hatching process. Knowledge of lipid compositions and localization could be helpful for formulating the diet for female broodstocks to promote fecundity and larval production.  相似文献   

20.
分析磷脂酰肌醇循环(PI cycle)的磷脂组分常采用双向薄层层析法.建立了一个简单快速的单向薄层层析分离肌醇磷脂方法.首先采用不同的有机溶剂体系分别提取非多磷酸肌醇磷脂和多磷酸肌醇磷脂,然后用不同的层析展开体系,对两部分磷脂进行单向薄层层析分离.采用无载体 32P标记实验对该方法分离效果进行了观察.此法适用于同位素标记和非标记样品中肌醇磷脂组分的比较分析及多磷酸肌醇磷脂的提取、纯化和定量.  相似文献   

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