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81.
Patent analysis with the help of the strategic mining of patents from databases is important and useful within the framework of application-oriented research and its commercialization. In the analysis reported here, we have mined cyanobacterial patents from the patent database of the United States Patent and Trademark Office (USPTO). In order to make an assessment of the commercial potentials of cyanobacteria, we conducted the patent search (from 1976 to April 2006) using certain generic terms and the 84 genera of cyanobacteria as keywords. The search was performed in two major ways – searching the abstracts and claims of the patents cumulatively and searching the entire patent documents by the mode of ‘all fields’ in USPTO. In the abstract- and claims-based search, 234 patents were obtained after the removal of overlapping patents among the keywords. An additional 31 patents were added following the ‘all fields’ search; these patents were not covered in the search that was based on abstracts and claims. The entire package of 265 patents, of which 244 were related to cyanobacteria, was then analyzed. Information derived from these patents identified five major areas of cyanobacterial utilization. Cyanobacteria have been patented as a source of a wide spectrum of products, for medical, agriculture and environmental applications, for gene-based products, for methods of cultivation and for methods of control. The chronological development in granting cyanobacterial patents was also traced. This study demonstrates that such strategic mining and analysis of patent data can be used as an index for future development.  相似文献   
82.
To synthesize and secrete heterologous proteins in an attenuated Vibrio anguillarum strain for potential multivalent live vaccine development, different antigen-delivery systems based on bacterial-originated secretion signal peptides (SPs) were designed and identified in this work. Four SPs were derived from hemolysin of Escherichia coli, RTX protein of V. cholerae, hemolysin of V. anguillarum, zinc-metalloprotease of V. anguillarum, respectively, and their abilities to support secretion of green fluorescent protein (GFP) in an attenuated V. anguillarum strain MVAV6203 were assayed. Immunodetection of GFP showed that the capability of the tested signal leaders to direct secretion of GFP varied greatly. Although all the four signal peptide-fused GFPs could be expressed correctly and trapped intracellularly in recombinant strains, only the EmpA signal peptide could confer efficient secretion to GFP. For the investigation of its potential application in live bacteria carrier vaccines, a heterologous protein EseB of Edwardsiella tarda was fused to the SP(empA) antigen-delivery system and introduced into the strain MVAV6203. Further analysis of EseB demonstrated that the constructed SP(empA) antigen-delivery system could be used to secrete foreign protein in attenuated V. anguillarum and be available for carrier vaccines development.  相似文献   
83.
Beckerman AP  Wieski K  Baird DJ 《Oecologia》2007,152(2):335-343
Predator-generated variation in prey energy intake remains the dominant explanation of adaptive response to predation risk in prey life history, morphology and physiology across a wide range of taxa. This "behavioural hypothesis" suggest that chemical or visual signals of predation risk reduce prey energy intake leading to a life history characterized by a small size and late age at maturity. However, size-selective predation can induce either smaller size-early age or large size-late age life history. The alternative "physiological hypothesis" suggests that size-selective cues decouple the relationship between energy and life history, acting instead directly on development. Here we use a series of experiments in a fish-daphnid predator-prey system to ask whether size-selective predator cues induce a physiological mediation of development, overshadowing behaviourally based changes in food intake. We found fish chemical cues reduce the net energy intake in Daphnia magna, suggesting a behaviourally mediated reduction in energy. Experimental manipulation of food levels show further that reductions in food lead to later but smaller size at maturity. However, in line with the physiological hypothesis, we show that D. magna matures earlier and at a smaller size when exposed to fish predation cues. Furthermore, our data shows that they do this by increasing their development rate (earlier maturity) for a given growth rate, resulting in a smaller size at maturity. Our data, from a classic size-selective predation system, indicate that predator-induced changes in this system are driven by physiological mediation of development rather than behavioural mediation of energy intake.  相似文献   
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Patient management in Idiopathic Pulmonary Fibrosis (IPF) is largely based on societal guidelines and recommendations. A recent update by the American Thoracic Society (ATS), European Respiratory Society (ERS), Japanese Respiratory Society (JRS) and Latin American Thoracic Association (ALAT) provided updated guidance on the diagnosis and management of IPF, along with recommendations on pharmacologic and non-pharmacologic approaches to patient management. The treatment guidance is based on GRADE criteria, which rates the quality of evidence according to previously published methodology. Here we discuss how to interpret the recent guideline updates and the implications of this guidance for clinical practice. In addition we discuss the assessment and recommendations for a number of pharmacological agents that have been the focus of clinical trials over the past years. Although no single pharmacological agent was recommended by the guidelines committee, we discuss how since then, more recent data have resulted in the approval of pirfenidone in Europe, and preliminary negative findings regarding the safety of a triple therapy regimen consisting of prednisone, azathioprine and N-acetylcysteine have raised the question of whether it is no longer a treatment option. As clinicians, we must interpret the available guidance and recommendations as we consider each individual patient and as we discuss the available clinical data and the patient’s own preferences in our approach to the management of this disease.  相似文献   
86.
The Miro GTPases represent an unusual subgroup of the Ras superfamily and have recently emerged as important mediators of mitochondrial dynamics and for maintaining neuronal health. It is now well-established that these enzymes act as essential components of a Ca2+-sensitive motor complex, facilitating the transport of mitochondria along microtubules in several cell types, including dopaminergic neurons. The Miros appear to be critical for both anterograde and retrograde mitochondrial transport in axons and dendrites, both of which are considered essential for neuronal health. Furthermore, the Miros may be significantly involved in the development of several serious pathological processes, including the development of neurodegenerative and psychiatric disorders. In this review, we discuss the molecular structure and known mitochondrial functions of the Miro GTPases in humans and other organisms, in the context of neurodegenerative disease. Finally, we consider the potential human Miros hold as novel therapeutic targets for the treatment of such disease.  相似文献   
87.
The genomes of Vibrio cholerae O1 Matlab variant MJ-1236, Mozambique O1 El Tor variant B33, and altered O1 El Tor CIRS101 were sequenced. All three strains were found to belong to the phylocore group 1 clade of V. cholerae, which includes the 7th-pandemic O1 El Tor and serogroup O139 isolates, despite displaying certain characteristics of the classical biotype. All three strains were found to harbor a hybrid variant of CTXΦ and an integrative conjugative element (ICE), leading to their establishment as successful clinical clones and the displacement of prototypical O1 El Tor. The absence of strain- and group-specific genomic islands, some of which appear to be prophages and phage-like elements, seems to be the most likely factor in the recent establishment of dominance of V. cholerae CIRS101 over the other two hybrid strains.Vibrio cholerae, a bacterium autochthonous to the aquatic environment, is the causative agent of cholera, a life-threatening disease that causes severe, watery diarrhea. Cholera bacteria are serogrouped based on their somatic O antigens, with more than 200 serogroups identified to date (6). Only toxigenic strains of serogroups O1 and O139 have been identified as agents of cholera epidemics and pandemics; serogroups other than O1 and O139 have the potential to cause mild gastroenteritis or, rarely, local outbreaks. Genes coding for cholera toxin (CTX), ctxAB, and other virulence factors have been shown to reside in bacteriophages and various mobile genetic elements. In addition, V. cholerae serogroup O1 is differentiated into two biotypes, classical and El Tor, by a combination of biochemical traits, by sensitivity to biotype-specific bacteriophages, and more recently by nucleotide sequencing of specific genes and by molecular typing (5, 17, 19).There have been seven pandemics of cholera recorded throughout human history. The seventh and current pandemic began in 1961 in the Indonesian island of Sulawesi and subsequently spread to Asia, Africa, and Latin America; the six previous pandemics are believed to have originated in the Indian subcontinent. Isolates of the sixth pandemic were almost exclusively of the O1 classical biotype, whereas the current (seventh) pandemic is dominated by the V. cholerae O1 El Tor biotype as the causative agent, a transition occurring between 1923 and 1961. Today, the disease continues to remain a scourge in developing countries, confounded by the fact that V. cholerae is native to estuaries and river systems throughout the world (8).Over the past 20 years, several new epidemic lineages of V. cholerae O1 El Tor have emerged (or reemerged). For example, in 1992, a new serogroup, namely, O139 of V. cholerae, was identified as the cause of epidemic cholera in India and Bangladesh (25). The initial concern was that a new pandemic was beginning; however, the geographic range of V. cholerae O139 is currently restricted to Asia. Additionally, V. cholerae O1 hybrids and altered El Tor variants have been isolated repeatedly in Bangladesh (Matlab) (23, 24) and Mozambique (1). Altered V. cholerae O1 El Tor isolates produce cholera toxin of the classical biotype but can be biotyped as El Tor by conventional phenotypic assays, whereas V. cholerae O1 hybrid variants cannot be biotyped based on phenotypic tests and can produce cholera toxin of either biotype. These new variants have subsequently replaced the prototype seventh-pandemic V. cholerae O1 El Tor strains in Asia and Africa, with respect to frequency of isolation from clinical cases of cholera (27).Here, we report the genome sequence of three V. cholerae O1 variants, MJ-1236, a Matlab type I hybrid variant from Bangladesh that cannot be biotyped by conventional methods, CIRS101, an altered O1 El Tor isolate from Bangladesh which harbors ctxB of classical origin, and B33, an altered O1 El Tor isolate from Mozambique which harbors classical CTXΦ, and we compare their genomes with prototype El Tor and classical genomes. From an epidemiological viewpoint, among the three variants characterized in this study, V. cholerae CIRS101 is currently the most “successful” in that strains belonging to this type have virtually replaced the prototype El Tor in Asia and many parts of Africa, notably East Africa. This study, therefore, gives us a unique opportunity to understand why V. cholerae CIRS101 is currently the most successful El Tor variant.  相似文献   
88.
89.
Although superhydrophobic materials have attracted much research interest in anti-icing,some controversy still exists.In this research,we report a cost-effective method used to verify the contribution of area fraction to ice adhesion strength.We tried to partially-embed siliea nanopnarticles into microscale fabrics of a commercial polyamide mesh.Then,the area fraction could be determined by altering the mesh size.Generally,the ice adhesion strength decreases as the area fraction decreases.An ice adhesion strength of~1.9 kPa and a delayed freezing time of~1048 s can be obtained.We attribute the low ice adhesion strength to the combination of superhydro-phobicity and stress concentration.The superhydrophobicity prohibits the water from penetrating into the voids of the meshes,and the small actual contact area leads to stress concentration which promotes interfacial crack propagation.Moreover,our superhydrophobic mesh simultaneously exhibis a micro-nano hierarchical structure and a partally-cmbedded structure.Therefore,the as-prepared superhydrophobic mesh retained the ieephobicity after 20 icingldeicing cycles,and maintained its superhydrophobicity even afier 60 sandpaper-abrasion cycles and a 220"C thermal treatment.  相似文献   
90.
Systems biology and its potential role in radiobiology   总被引:1,自引:0,他引:1  
About a century ago, Conrad Röentgen discovered X-rays, and Henri Becquerel discovered a new phenomenon, which Marie and Pierre Curie later coined as radio-activity. Since their seminal work, we have learned much about the physical properties of radiation and its effects on living matter. Alas, the more we discover, the more we appreciate the complexity of the biological processes that are triggered by radiation exposure and eventually lead (or do not lead) to disease. Equipped with modern biological methods of high-throughput experimentation, imaging, and vastly increased computational prowess, we are now entering an era where we can piece some of the multifold aspects of radiation exposure and its sequelae together, and develop a more systemic understanding of radiogenic effects such as radio-carcinogenesis than has been possible in the past. It is evident from the complexity of even the known processes that such an understanding can only be gained if it is supported by mathematical models. At this point, the construction of comprehensive models is hampered both by technical inadequacies and a paucity of appropriate data. Nonetheless, some initial steps have been taken already and the generally increased interest in systems biology may be expected to speed up future progress. In this context, we discuss in this article examples of relatively small, yet very useful models that elucidate selected aspects of the effects of exposure to ionizing radiation and may shine a light on the path before us.  相似文献   
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