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991.
Takashi Saitoh Jun Osawa Toshikazu Takanishi Shintaro Hayakashi Masaaki Ohmori Toshio Morita Shigeru Uemura Jon Olav Vik Nils Chr. Stenseth Koji Maekawa 《Population Ecology》2007,49(3):249-256
The effects of the abundance of acorns of the oak, Quercus crispula, on the population dynamics of three rodent species (Apodemus speciosus, A. argenteus, and Clethrionomys rufocanus) were analyzed using time series data (1992–2006). The data were obtained in a forest in northern Hokkaido, Japan, by live
trapping rodents and directly counting acorns on the ground. Apodemus speciosus generally increased in abundance following acorn masting. However, the clear effect of acorn abundance was not detected for
the other two rodent species. Acorns of Q. crispula contain tannins, which potentially have detrimental effects on herbivores. Apodemus speciosus may reduce the damage caused by acorn tannins with tannin-binding salivary proteins and tannase-producing bacteria, whereas
such physiological tolerance to tannins is not known in the other two rodent species. The differences in the effects of acorns
between the three species may be due to differences in their physiological tolerance to tannins. 相似文献
992.
Strategic mining of cyanobacterial patents from the USPTO patent database and analysis of their scope and implications 总被引:2,自引:0,他引:2
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
993.
The current treatment strategies, chemotherapy and radiation therapy being used for the management of cancer are deficient
in targeted approach leading to treatment related toxicities and relapse. Contrarily, fusion toxins exhibit remarkable tumor
specificity thus emerging as an alternative therapy for the treatment of cancer. Diphtheria toxin-HN-1 peptide (DT/HN-1) is
a fusion toxin designed to target the head and neck squamous cell carcinoma (HNSCC). The aim of this study was to construct,
characterize, and evaluate the cytotoxicity and specificity of DT/HN-1 fusion toxin against the HNSCC cells. The purified
DT/HN-1 fusion toxin was characterized by SDS-PAGE and western blotting. Refolding of purified fusion toxins was monitored
by fluorescence spectra and circular dichroism spectra. The activity of DT/HN-1 fusion toxin was demonstrated on various HNSCC
cell lines by cell viability assay, cell proliferation assay, protein synthesis inhibition assay, apoptosis and cell cycle
analysis. The fusion toxin DT/HN-1 demonstrated remarkably high degree of cytotoxicity specific to the HNSCC cells. The IC50 of DT/HN-1 fusion toxin was ~1 to 5 nM in all the three HNSCC cell lines. The percentage apoptotic cells in DT/HN-1 treated
UMB-SCC-745 cells are 16% compared to 4% in untreated. To further demonstrate the specific toxicity of DT/HN-1 fusion toxin
towards the HNSCC cells we constructed, characterized and evaluated the efficacy of DT protein. The DT protein coding for
only a fragment of diphtheria toxin without its native receptor binding domain failed to exhibit any cytotoxicity on all the
cell lines used in this study thus establishing the importance of a ligand in achieving targeted toxicity. To evaluate the
translocation ability of HN-1 peptide, an additional construct DTΔT/HN-1 was constructed, characterized and evaluated for
its cytotoxic activity. The fusion toxin DTΔT/HN-1 deficient of the translocation domain of diphtheria toxin showed no cytotoxicity
on all the cell lines clearly indicating the inability of HN-1 peptide to translocate catalytic domain of the toxin into the
cytosol. 相似文献
994.
Neuroglia is critically important for controlling the brain homeostasis and for mounting the brain defence against pathological
insults. Here, we overview recent data about the role of neuroglia in various types of neurodegenerative diseases (Alzheimer’s
disease, Parkinson’s disease, fronto-temporal dementia, Wernicke encephalopathy, amyotrophic lateral sclerosis and immunodeficiency
virus-1-associated dementia). In all these forms of neurodegeneration, astroglia undergoes complex morphological and functional
changes. The early and mid-term stages of neurodegenerative processes, and specifically of Alzheimer’s disease, are associated
with generalised atrophy of astroglia, whereas the later stages are characterised with an astrogliosis and microglial activation
linked to neuropathological lesions such as senile plaques. Atrophic changes in astroglia may contribute to the initial cognitive
deficits due to reduced glial synaptic coverage and decreased neuroprotection. 相似文献
995.
Carlo Paribello Leeping Tao Anthony Folino Elizabeth Berry-Kravis Michael Tranfaglia Iryna M Ethell Douglas W Ethell 《BMC neurology》2010,10(1):91
Background
Fragile X syndrome (FXS) is a disorder characterized by a variety of disabilities, including cognitive deficits, attention-deficit/hyperactivity disorder, autism, and other socio-emotional problems. It is hypothesized that the absence of the fragile X mental retardation protein (FMRP) leads to higher levels of matrix metallo-proteinase-9 activity (MMP-9) in the brain. Minocycline inhibits MMP-9 activity, and alleviates behavioural and synapse abnormalities in fmr1 knockout mice, an established model for FXS. This open-label add-on pilot trial was conducted to evaluate safety and efficacy of minocycline in treating behavioural abnormalities that occur in humans with FXS. 相似文献996.
Zhou L Liu Q Wang Q Ma Y Xu Y Yang Z Zhao Y Zhang Y 《Applied microbiology and biotechnology》2008,79(6):1027-1034
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
997.
Jae Yeon Park Yang Hee Kim Andrew Seong Young Je Yoo 《Biotechnology and Bioprocess Engineering》2008,13(4):431-435
An amperometric glucose biosensor was designed for the detection of glucose in blood, urine, beverages, and fermentation systems.
In typical glucose biosensors that employ enzymes, mediators are used for efficient electron transfer between the enzymes
and the electrode. However, some of these mediators are known to be toxic to the enzymes and also must be immobilized on the
surface of the electrode. We propose a mediator-free glucose biosensor that uses a glucose oxidase immobilized on a tin oxide
electrode. Direct electron transfer is possible in this system because the tin oxide has redox properties similar to those
of mediators. The method for immobilization of the glucose oxidase onto the tin oxide is also very simple. Tin oxide was prepared
by the anodization and annealing of pure tin, and this provides a large surface area for the immobilization step because of
its porosity. Glucose oxidase was immobilized onto the tin oxide using the membrane entrapment method. The proposed method
provides a simple process for fabricating the enzyme electrode. Glucose oxidase immobilized onto the tin oxide, prepared in
accordance with this method, has a relatively large current response when comparedto those of other glucose biosensors. The
sensitivity of the biosensor was 19.55 μA/mM, and a linear response was observed between 0∼3 mM glucose. This biosensor demonstrated
good reproducibility and stability. 相似文献
998.
Analysis of individual cells identifies cell‐to‐cell variability following induction of cellular senescence
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Christopher D. Wiley James M. Flynn Christapher Morrissey Ronald Lebofsky Joe Shuga Xiao Dong Marc A. Unger Jan Vijg Simon Melov Judith Campisi 《Aging cell》2017,16(5):1043-1050
Senescent cells play important roles in both physiological and pathological processes, including cancer and aging. In all cases, however, senescent cells comprise only a small fraction of tissues. Senescent phenotypes have been studied largely in relatively homogeneous populations of cultured cells. In vivo, senescent cells are generally identified by a small number of markers, but whether and how these markers vary among individual cells is unknown. We therefore utilized a combination of single‐cell isolation and a nanofluidic PCR platform to determine the contributions of individual cells to the overall gene expression profile of senescent human fibroblast populations. Individual senescent cells were surprisingly heterogeneous in their gene expression signatures. This cell‐to‐cell variability resulted in a loss of correlation among the expression of several senescence‐associated genes. Many genes encoding senescence‐associated secretory phenotype (SASP) factors, a major contributor to the effects of senescent cells in vivo, showed marked variability with a subset of highly induced genes accounting for the increases observed at the population level. Inflammatory genes in clustered genomic loci showed a greater correlation with senescence compared to nonclustered loci, suggesting that these genes are coregulated by genomic location. Together, these data offer new insights into how genes are regulated in senescent cells and suggest that single markers are inadequate to identify senescent cells in vivo. 相似文献
999.
Tao Chen Yu Wu Yuzi Wang Jigao Zhu Haiying Chu Li Kong Liangwei Yin Haiying Ma 《Neurochemical research》2017,42(11):3073-3083
Brain-derived neurotrophic factor (BDNF) plays an important role in promoting the growth, differentiation, survival and synaptic stability of neurons. Presently, the transplantation of neural stem cells (NSCs) is known to induce neural repair to some extent after injury or disease. In this study, to investigate whether NSCs genetically modified to encode the BDNF gene (BDNF/NSCs) would further enhance synaptogenesis, BDNF/NSCs or naive NSCs were directly engrafted into lesions in a rat model of traumatic brain injury (TBI). Immunohistochemistry, western blotting and RT-PCR were performed to detect synaptic proteins, BDNF-TrkB and its downstream signaling pathways, at 1, 2, 3 or 4 weeks after transplantation. Our results showed that BDNF significantly increased the expression levels of the TrkB receptor gene and the phosphorylation of the TrkB protein in the lesions. The expression levels of Ras, phosphorylated Erk1/2 and postsynaptic density protein-95 were elevated in the BDNF/NSCs-transplanted groups compared with those in the NSCs-transplanted groups throughout the experimental period. Moreover, the nuclear factor (erythroid-derived 2)-like 2/Thioredoxin (Nrf2/Trx) axis, which is a specific therapeutic target for the treatment of injury or cell death, was upregulated by BDNF overexpression. Therefore, we determined that the increased synaptic proteins level implicated in synaptogenesis might be associated with the activation of the MAPK/Erk1/2 signaling pathway and the upregulation of the antioxidant agent Trx modified by BDNF-TrkB following the BDNF/NSCs transplantation after TBI. 相似文献
1000.
Can Yuan Wenjuan Zhong Fangsheng Mou Yiyun Gong Deqiang Pu Peicheng Ji Haiyan Huang Zehu Yang Chao Zhang 《Physiology and Molecular Biology of Plants》2017,23(1):35-41
Chloroplast genome sequences are very useful for species identification and phylogenetics. Chuanminshen (Chuanminshen violaceum Sheh et Shan) is an important traditional Chinese medicinal plant, for which the phylogenetic position is still controversial. In this study, the complete chloroplast genome of Chuanminshen violaceum Sheh et Shan was determined. The total size of Chuanminshen chloroplast genome was 154,529 bp with 37.8% GC content. It has the typical quadripartite structure, a large single copy (17,800 bp) and a small single copy (84,171 bp) and a pair of inverted repeats (26,279 bp). The whole genome harbors 132 genes, which includes 85 protein coding genes, 37 tRNA genes, eight rRNA genes, and two pseudogenes. Thirty-nine SSR loci, 32 tandem repeats and 49 dispersed repeats were found. Phylogenetic analyses results with the help of MEGA showed a new insight for the Chuanminshen phylogenetic relationship with the reported chloroplast genomes in Apiales plants. 相似文献