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71.
Anna C. Giddens Swarna A. Gamage Jackie D. Kendall Woo-Jeong Lee Bruce C. Baguley Christina M. Buchanan Stephen M.F. Jamieson James M.J. Dickson Peter R. Shepherd William A. Denny Gordon W. Rewcastle 《Bioorganic & medicinal chemistry》2019,27(8):1529-1545
Replacing one of the morpholine groups of the phosphatidylinositol 3-kinase (PI3K) inhibitor ZSTK474 with a variety of sulfonamide-linked solubilizing substituents produced a new class of active and potent PI3Kα inhibitors, with several derivatives demonstrating high PI3Kα enzyme potency and good cellular potency in two human derived cell lines. The overall results suggest a preference for linear and somewhat flexible solubilizing functions. From this series, compound 16, also known as SN32976, was selected for advanced preclinical evaluation. 相似文献
72.
This study contrasts the actual conservation spending and the Australian public’s demand for conservation funding for two
Australian mammal species, the koala and the northern hairy-nosed wombat. It involves a survey of 204 members of the Australian
public. Willingness to fund conservation action to protect the northern hairy-nosed wombat was found to be higher than that
for the koala despite the koala’s immense popularity. The critically endangered status of the northern-hairy nosed wombat
and the more secure conservation status of the koala is a factor likely to have influenced the comparative willingness-to-pay
decisions. Actual annual conservation expenditure for both species is lower than the estimated aggregate willingness-to-pay
for their conservation. Furthermore, conservation funding for the koala is much more than that for the northern hairy-nosed
wombat even though the estimated public willingness-to-pay (demand) for funding koala conservation was less than for this
wombat species. Reasons for this are suggested. They may also help to explain misalignment between demand for conservation
funding of other species involving differences in charisma and endangerment. 相似文献
73.
The future of the orangutan (Pongo spp.) is far from secure despite the species’ high profile and media attention. The traditional threat to the orangutan has
been widespread logging, but the continuing conversion of remaining habitat for oil palm (Elaeis guineensis) cultivation is hastening its extinction in the wild. This situation is driven by a robust global market for palm oil as
a vegetable oil and biofuel. In tackling this conservation problem, therefore, economic factors cannot be overlooked. This
article analyses these factors and how they curtail effective orangutan conservation. Of significance are the high opportunity
costs of orangutan conservation and market failures associated with the public-goods nature of the orangutan’s forest habitat.
Conservationists should consider these constraints when formulating remedial action. This article assesses strategies that
reduce the opportunity cost of conserving habitat (via supply-side approaches that divert oil palm cultivation away from forests)
and enhance the realisable value of orangutan habitat (by capitalising on the demand for non-market values such as carbon
storage). It is concluded that the former group of strategies are likely to have limited effect on curtailing deforestation,
but with the right institutional policies in place they can act as stopgaps while strategies involving carbon financing and
payments for biodiversity develop sufficiently to render habitat retention financially competitive.
相似文献
Clem TisdellEmail: |
74.
Swarna A. Gamage Darby G. Brooke Sanjeev Redkar Jharna Datta Samson T. Jacob William A. Denny 《Bioorganic & medicinal chemistry》2013,21(11):3147-3153
A series of 4-anilinoquinoline derivatives related to the known inhibitor SGI-1027, containing side chains of varying pKa, were prepared by acid-catalysed coupling of the pre-formed side chains with 4-chloroquinolines. The compounds were evaluated for their ability to reduce the level of DNMT1 protein in HCT116 human colon carcinoma cells by Western blotting. With a very strongly basic N-methylpyridinium side chain, only NHCO-linked compounds were effective, whereas less strongly basic ((diaminomethylene)hydrazono)ethyl or 3-methylpyrimidine-2,4-diamine side chains allowed both NHCO- and CONH-linked compounds to show activity. In contrast, the pKa of the quinoline unit had little apparent influence on activity. 相似文献
75.
Patagar Dayanand Uttarkar Akshay Patra Swarna M. Patil Jagadish H. Kusanur Raviraj Niranjan Vidya Kumar H. G. Ashok 《Russian Journal of Bioorganic Chemistry》2021,47(2):390-398
Russian Journal of Bioorganic Chemistry - 1,5-Benzodiazepines are one of the important class of tranquilizers. The fusion of heterocyclic systems like coumarins and indolines with the... 相似文献
76.
ABSTRACT: BACKGROUND: The parathyroid hormone (PTH)-family consists of a group of structurally related factors that regulate calcium and bone homeostasis and are also involved in development of organs such as the heart, mammary gland and immune system. They interact with specific members of family 2 B1 G-protein coupled receptors (GPCRs), which have been characterised in teleosts and mammals. Two PTH/PTHrP receptors, PTH1R and PTH2R exist in mammals and in teleost fish a further receptor PTH3R has also been identified. Recently in chicken, PTHfamily members involved in calcium transport were characterized and specific PTHRs are suggested to exist although they have not yet been isolated or functionally characterized. The aim of this study is to further explore the evolution and function of the vertebrate PTH/PTHrP system through the isolation, phylogenetic analysis and functional characterization of the chicken receptors. RESULTS: Two PTHRs were isolated in chicken and sequence comparison and phylogenetic analysis indicate that the chicken receptors correspond to PTH1R and PTH3R, which emerged prior to the teleost/tetrapod divergence since they are present in cartilaginous fish. The vertebrate PTH2R receptor and its ligand TIP39 have been lost from bird genomes. Chicken PTH1R and PTH3R have a divergent and widespread tissue expression and are also evident in very early embryonic stages of development. Receptor stimulation studies using HEK293 cells stably expressing the chicken PTH1R and PTH3R and monitoring cAMP production revealed they are activated by chicken 1-34 N-terminal PTH-family peptides in a dose dependent manner. PTH-L and PTHrP were the most effective peptides in activating PTH1R (EC50 = 7.7 nM and EC50 = 22.7 nM, respectively). In contrast, PTH-L (100 nM) produced a small cAMP accumulation on activation of PTH3R but PTHrP and PTH (EC50 = 2.5 nM and EC50 = 22.1 nM, respectively) readily activated the receptor. PTHrP also stimulated intracellular Ca2+ accumulation on activation of PTH1R but not PTH3R. CONCLUSION: Two PTHR homologues of the vertebrate PTH1R and PTH3R were isolated and functionally characterized in chicken. Their distinct pattern of expression during embryo development and in adult tissues, together with their ligand preference, suggests that they have acquired specific functions, which have contributed to their maintenance in the genome. PTH2R and its activating ligand, TIP39, are absent from bird genomes. Nonetheless identification of putative PTH2R and TIP39 in the genome of an ancient agnathan, lamprey, suggests the PTH/PTHrP ligand and receptor family was already present in an early basal paraphyletic group of vertebrates and during the vertebrate radiation diverged via gene/genome duplication and deletion events. Knowledge of the role PTH/PTHrP system in early vertebrates will help to establish evolution of function. 相似文献
77.
Marjolein?Helder David?PBTB?StrikEmail author Hubertus?VM?Hamelers Cees?JN?Buisman 《Biotechnology for biofuels》2012,5(1):70
Due to a growing world population and increasing welfare, energy demand worldwide is increasing. To meet the increasing energy demand in a sustainable way, new technologies are needed. The Plant-Microbial Fuel Cell (P-MFC) is a technology that could produce sustainable bio-electricity and help meeting the increasing energy demand. Power output of the P-MFC, however, needs to be increased to make it attractive as a renewable and sustainable energy source. To increase power output of the P-MFC internal resistances need to be reduced. With a flat-plate P-MFC design we tried to minimize internal resistances compared to the previously used tubular P-MFC design. With the flat-plate design current and power density per geometric planting area were increased (from 0.15 A/m2 to 1.6 A/m2 and from 0.22 W/m2 to and 0.44 W/m2)as were current and power output per volume (from 7.5 A/m3 to 122 A/m3 and from 1.3 W/m3 to 5.8 W/m3). Internal resistances times volume were decreased, even though internal resistances times membrane surface area were not. Since the membrane in the flat-plate design is placed vertically, membrane surface area per geometric planting area is increased, which allows for lower internal resistances times volume while not decreasing internal resistances times membrane surface area. Anode was split into three different sections on different depths of the system, allowing to calculate internal resistances on different depths. Most electricity was produced where internal resistances were lowest and where most roots were present; in the top section of the system. By measuring electricity production on different depths in the system, electricity production could be linked to root growth. This link offers opportunities for material-reduction in new designs. Concurrent reduction in material use and increase in power output brings the P-MFC a step closer to usable energy density and economic feasibility. 相似文献
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79.
Vitamin E has been used for more than 50 years in experimental and clinical dermatology. While a large number of case reports were published in this time, there is still a lack of controlled clinical studies providing a rationale for well defined dosages and clinical indications. In contrast, advances in basic research on the physiology, mechanism of action, penetration, bioconversion and photoprotection of vitamin E in human skin has led to the development of numerous new formulations for use in cosmetics and skin care products. This article reviews basic mechanisms and possible cosmetic as well as clinical implications of the recent advances in cutaneous vitamin E research. Experimental evidence suggests that topical and oral vitamin E has antitumorigenic, photoprotective, and skin barrier stabilizing properties. While the current use of vitamin E is largely limited to cosmetics, controlled clinical studies for indications such as atopic dermatitis or preventions of photocarcinogenesis are needed to evaluate the clinical benefit of vitamin E. 相似文献
80.
Mandali SL Stoecker BJ Maxwell CV de Rodas BZ Arquitt AB 《Biological trace element research》2002,88(2):145-151
Endotoxin, a product of bacterial infections, was used to investigate the effects acute infections on chromium (Cr) uptake in early weaned (14 d of age) pigs. At d 18, pigs were anesthetized, and a 2-mm silastic jugular catheter was inserted and passed subcutaneously to a dorsal position behind the ear. At d 21, pigs were deprived of food for 7 h and injected intraperitoneally with saline or 25 microg endotoxin (lipopolysaccharide from Escherichia coli serotype 0111:B4) per kg body wt suspended in 9 g/L saline. One hour after dosing, an oral dose of 0.7 mCi of 51CrCl3 was given by micropipet. Blood was sampled from the catheter at intervals until necropsy at 8 h after the 51CrCl3 dose. Blood and tissue samples were counted in a gamma counter. 51Cr in blood was significantly lower at 3, 4, 5, 6, and at 8 h after dosing in endotoxin-injected pigs compared to controls. Eight hours after 51CrCl3 dosing, 51Cr retention was significantly lower in the liver, heart, and kidney in endotoxin-treated pigs and tended to be lower in spleen (p<0.06) and in urine (p<0.16) with endotoxin treatment. These data suggest that during acute infection, there might be decreased Cr uptake and retention. 相似文献