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991.
992.
DNA vaccines consisted of tumor-associated antigen (TAA) are well suited for immunotherapy against tumor. The construct can
contain TAA fused to an appropriate molecule (biologic adjuvant) to improve the efficacy of anti-tumor immune response. Heat
shock protein 70 (HSP70) has been shown to be an excellent candidate, capable of cross-priming TAA by antigen presenting cells
leading to a robust T-cell response. However, the relationship between strong T-cell responses and tumor rejection is not
always mutually exclusive, for which TAA loss or activation of suppressive mechanisms may occur. HSP70 fused to downstream
of Her2/neu as DNA vaccine has been shown to be efficient against Her2-expressing tumors. In this study, we examined if N-terminally
fusion of Her2/neu to HSP70 could also improve efficiency of Her2/neu DNA vaccine. Therefore, mice with an established Her2/neu
expressing tumor were immunized with DNA vaccine consisting of extracellular and trans-membrane domain (EC+TM) of rat Her2/neu
alone or N-terminally fused to HSP70 and immune response was evaluated. Administration of rat Her2/neu led to partial control
of tumor progression. Surprisingly, fusion of HSP70 to N-terminal of rat Her2/neu led to tumor progression. Our result proposes
that fusion direction of biologic adjuvant is an important consideration when Her2/neu is used. 相似文献
993.
Veli-Matti Väänänen Petri Nummi Hannu Pöysä Martti Rask Kari Nyberg 《Hydrobiologia》2012,697(1):85-93
We studied the hypothesis that fish play an important role in lake use by ducks (pairs and broods) in boreal lakes. The study was based on densities of different duck and fish species in 28 boreal lakes in southern Finland. We focused on the three most common duck species (mallard Anas platyrhynchos, green-winged teal A. crecca and common goldeneye Bucephala clangula) and on the three most common fish species (perch Perca fluviatilis, roach Rutilus rutilus and pike Esox lucius) in the region. We considered both competitive and predatory interactions between ducks and fish, the perch and roach being potential competitors with ducks and the pike a potential predator of ducks. We found a negative association between green-winged teal brood density and total fish density, the other duck species having only a weak association with total fish density. When the three fish species were considered separately, a negative association, suggesting food competition, was found between perch, green-winged teal and goldeneye, whereas the role of roach as a food competitor seemed to be of minor importance. We did not find any clear signs of predatory effects of pike on ducks. Our results suggest that food competition is a more important factor than pike predation in affecting lake use by ducks in oligotrophic boreal environments in southern Finland. 相似文献
994.
995.
Atul A. Lohade Rajesh R. Jain Krishna Iyer Sushant K. Roy Hemant H. Shimpi Yogita Pawar M. G. R. Rajan Mala D. Menon 《AAPS PharmSciTech》2016,17(6):1298-1311
Targeted drug delivery systems for cancer improves anti-tumor efficacy and reduces systemic toxicity by restricting availability of cytotoxic drugs within tumors. Targeting moieties, such as natural ligands (folic acid, transferrin, and biotin) which are overexpressed on tumors, have been used to enhance liposome-encapsulated drug accumulation within tumors and resulted in better control. In this report, we explored the scope of targeting ligand folic acid, which is incorporated in liposome systems using folic acid-modified cholesterol (CPF), enabled highly selective tumor-targeted delivery of liposome-encapsulated doxorubicin and resulted in increased cytotoxicity within tumors. Folate-tagged poloxamer-coated liposomes (FDL) were found to have significantly higher cellular uptake than conventional poloxamer-coated liposomes (DL), as confirmed by fluorometric analysis in B16F10 melanoma cells. Biodistribution study of the radiolabeled liposomal system indicated the significantly higher tumor uptake of FDL as compared to DL. Anti-tumor activity of FDL against murine B16F10 melanoma tumor-bearing mice revealed that FDL inhibited tumor growth more efficiently than the DL. Taken together, the results demonstrated the significant potential of the folate-conjugated nanoliposomal system for drug delivery to tumors. 相似文献
996.
Ricardo Kriebel 《Brittonia》2012,64(1):6-14
A synopsis of the annual genus Poteranthera is presented here. Three species are recognized including the newly described Poteranthera windischii. Poteranthera is characterized by its annual life cycle, generally linear leaves that have conspicuous gland-tipped hairs on the lamina
margin, 5-merous flowers with a constriction at the level of the torus, one cycle of stamens reduced to staminodia or absent
altogether, three locular ovary, and reniform seeds with a foveolate testa. The flowers of the new species P. windischii are strongly heterandrous, where the usual set of stamens that bees harvest pollen from is reduced to staminodia and the
stamen set that deposits pollen on the bee has large yellow ventral appendages that possibly function as pollen mimics and
result in deceit pollination. This hypothesis is supported by experiments that have demonstrated innate preferences of female
bees for yellow, UV absorbing colors in flowers. Species of Poteranthera are extremely rare, known from very few specimens and possibly highly endangered. 相似文献
997.
Thaiany Quevedo Melo Sjef J. C. V. M. Copray Merari F. R. Ferrari 《Neurochemical research》2018,43(12):2212-2223
Parkinson’s disease (PD) is characterized by the presence of insoluble protein clusters containing α-synuclein. Impairment of mitochondria, endoplasmic reticulum, autophagy and intracellular trafficking proper function has been suggested to be caused by α-synuclein toxicity, which is also associated with the higher levels of ROS found in the aged brain and in PD. Oxidative stress leads to protein oligomerization and aggregation that impair autophagy and mitochondrial dynamics leading to a vicious cycle of organelles damage and neurodegeneration. In this review we focused on the role of α-synuclein dysfunction as a cellular stressor that impairs mitochondria, endoplasmic reticulum, autophagy and cellular dynamics culminating with dopaminergic depletion and the pathogenesis of PD. 相似文献
998.
Tropical forests are paramount in regulating the global carbon cycle due to the storage of large amounts of carbon in their biomass. Using repeat censuses of permanent plots located at 15 sites in the Andes Mountains of northwest Colombia, we evaluate: (1) the relationship between aboveground biomass (AGB) stocks, AGB dynamics (mortality, productivity, and net change), and changes in temperature across a ca. 3000-m elevational gradient (≈?16.1 °C); (2) how AGB mortality and AGB productivity interact to determine net AGB change; and (3) the extent to which either fine-grain (0.04-ha) or coarse-grain (1-ha) processes determine the AGB dynamics of these forests. We did not find a significant relationship between elevation/temperature and biomass stocks. The net AGB sequestered each year by these forests (2.21?±?0.51 Mg ha?1 year?1), equivalent to approximately 1.09% of initial AGB, was primarily determined by tree growth. Both forest structural properties and global warming influenced AGB mortality and net change. AGB productivity increases with greater inequality of tree sizes, a pattern characteristic of forest patches recovering from disturbances. Overall, we find that global warming is triggering directional changes in species composition by thermophilization via increased tree mortality of species in the lower portions of their thermal ranges and that the inclusion of small-scale forest structural changes can effectively account for endogenous processes such as changes in forest structure. The inclusion of fine-grain processes in assessments of AGB dynamics could provide additional insights about the effects that ongoing climate change has on the functioning of tropical montane forests. 相似文献
999.
The endoplasmic reticulum (ER) plays essential roles indispensable for cellular activity and survival, including functions such as protein synthesis, secretory and membrane protein folding, and Ca2+ release in cells. The ER is sensitive to stresses that can lead to the aggregation and accumulation of misfolded proteins, which eventually triggers cellular dysfunction; severe or prolonged ER stress eventually induces apoptosis. ER stress-induced apoptosis causes several devastating diseases such as atherosclerosis, neurodegenerative diseases, and diabetes. In addition, the production of biopharmaceuticals such as monoclonal antibodies requires the maintenance of normal ER functions to achieve and maintain the production of high-quality products in good quantities. Therefore, it is necessary to develop methods to efficiently relieve ER stress and protect cells from ER stress-induced apoptosis. The silkworm storage protein 1 (SP1) has anti-apoptotic activities that inhibit the intrinsic mitochondrial apoptotic pathway. However, the role of SP1 in controlling ER stress and ER stress-induced apoptosis has not been investigated. In this paper, we demonstrate that SP1 can inhibit apoptosis induced by a well-known ER stress inducer, thapsigargin, by alleviating the decrease in cell viability and mitochondrial membrane potential. Interestingly, SP1 significantly blocked increases in CHOP and GRP78 expression as well as ER Ca2+ leakage into the cytosol following ER stress induction. This indicates that SP1 protects cells from ER stressinduced apoptosis by functioning as an upstream inhibitor of apoptosis. Therefore, studying SP1 function can offer new insights into protecting cells against ER stress-induced apoptosis for future applications in the biopharmaceutical and medicine industries. 相似文献
1000.
Hee Jin Park Hyeong Cheol Park Sang Yeol Lee Hans J. Bohnert Dae-Jin Yun 《Journal of Plant Biology》2011,54(5):275-285
Posttranslational modifications of proteins by small polypeptides including ubiquitination, neddylation (related to ubiquitin
(RUB) conjugation), and sumoylation are implicated in plant growth and development, and they regulate protein degradation,
location, and interaction with other proteins. Ubiquitination mediates the selective degradation of proteins by the ubiquitin
(Ub)/proteasome pathway. The ubiquitin-like protein RUB is conjugated to cullins, which are part of a ubiquitin E3 ligase
complex that is involved in auxin hormonal signaling. Sumoylation, by contrast, is known for its involvement in guiding protein
interactions related to abiotic and biotic stresses and in the regulation of flowering time. ATG8/ATG12-mediated autophagy
influences degradation and recycling of cellular components. Other ubiquitin-like modifiers (ULPs) such as homology to Ub-1,
ubiquitin-fold modifier 1, and membrane-anchored Ub-fold are also found in Arabidopsis. ULPs share similar three-dimensional structures and a conjugation system, including E1 activating enzymes, E2 conjugation
enzymes, and E3 ligases, as well as proteases for deconjugation and recycling of the tags. However, each of the ULP posttranslational
modifications possesses its own specific enzymes and modifies its specific targets selectively. This review discusses recent
findings on ubiquitination and ubiquitin-like modifier processes and their roles in the posttranslational modification of
proteins in Arabidopsis. 相似文献