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991.
Assessing the outcomes of interventions in mental health care is both important and challenging. The aim of this paper is to advance the field of outcomes research by proposing a taxonomy of the decisions that clinicians and researchers need to consider when evaluating outcomes. Our taxonomy has eight components, framed as decisions: Whose outcome will be considered? Which scientific stage is being investigated? What outcome domain(s) matter? What level of assessment will be used? Will clinical and/or recovery outcomes be assessed? Whose perspective will be considered? Will deficits and/or strengths be the focus? Will invariant or individualized measures be preferred? We propose a future focus on understanding what matters most to people using mental health services, and on the use of measures rated by service users as the primary approach to evaluating outcome. 相似文献
992.
993.
Reduced maximal inhibition in phenotypic susceptibility assays indicates that viral strains resistant to the CCR5 antagonist maraviroc utilize inhibitor-bound receptor for entry 下载免费PDF全文
Westby M Smith-Burchnell C Mori J Lewis M Mosley M Stockdale M Dorr P Ciaramella G Perros M 《Journal of virology》2007,81(5):2359-2371
Maraviroc is a CCR5 antagonist in clinical development as one of a new class of antiretrovirals targeting human immunodeficiency virus type 1 (HIV-1) coreceptor binding. We investigated the mechanism of HIV resistance to maraviroc by using in vitro sequential passage and site-directed mutagenesis. Serial passage through increasing maraviroc concentrations failed to select maraviroc-resistant variants from some laboratory-adapted and clinical isolates of HIV-1. However, high-level resistance to maraviroc was selected from three of six primary isolates passaged in peripheral blood lymphocytes (PBL). The SF162 strain acquired resistance to maraviroc in both treated and control cultures; all resistant variants were able to use CXCR4 as a coreceptor. In contrast, maraviroc-resistant virus derived from isolates CC1/85 and RU570 remained CCR5 tropic, as evidenced by susceptibility to the CCR5 antagonist SCH-C, resistance to the CXCR4 antagonist AMD3100, and an inability to replicate in CCR5 Delta32/Delta32 PBL. Strain-specific mutations were identified in the V3 loop of maraviroc-resistant CC1/85 and RU570. The envelope-encoding region of maraviroc-resistant CC1/85 was inserted into an NL4-3 background. This recombinant virus was completely resistant to maraviroc but retained susceptibility to aplaviroc. Reverse mutation of gp120 residues 316 and 323 in the V3 loop (numbering from HXB2) to their original sequence restored wild-type susceptibility to maraviroc, while reversion of either mutation resulted in a partially sensitive virus with reduced maximal inhibition (plateau). The plateaus are consistent with the virus having acquired the ability to utilize maraviroc-bound receptor for entry. This hypothesis was further corroborated by the observation that a high concentration of maraviroc blocks the activity of aplaviroc against maraviroc-resistant virus. 相似文献
994.
Value estimates of ecosystem goods and services are useful to justify the allocation of resources towards conservation, but inconclusive estimates risk unsustainable resource allocations. Here we present replacement costs as a more accurate value estimate of insect pollination as an ecosystem service, although this method could also be applied to other services. The importance of insect pollination to agriculture is unequivocal. However, whether this service is largely provided by wild pollinators (genuine ecosystem service) or managed pollinators (commercial service), and which of these requires immediate action amidst reports of pollinator decline, remains contested. If crop pollination is used to argue for biodiversity conservation, clear distinction should be made between values of managed- and wild pollination services. Current methods either under-estimate or over-estimate the pollination service value, and make use of criticised general insect and managed pollinator dependence factors. We apply the theoretical concept of ascribing a value to a service by calculating the cost to replace it, as a novel way of valuing wild and managed pollination services. Adjusted insect and managed pollinator dependence factors were used to estimate the cost of replacing insect- and managed pollination services for the Western Cape deciduous fruit industry of South Africa. Using pollen dusting and hand pollination as suitable replacements, we value pollination services significantly higher than current market prices for commercial pollination, although lower than traditional proportional estimates. The complexity associated with inclusive value estimation of pollination services required several defendable assumptions, but made estimates more inclusive than previous attempts. Consequently this study provides the basis for continued improvement in context specific pollination service value estimates. 相似文献
995.
996.
Wing-yiu Lee Peter Hampson Lydia Coulthard Farrah Ali Mike Salmon Janet M. Lord Dagmar Scheel-Toellner 《The Journal of biological chemistry》2010,285(31):23889-23898
Members of the protein kinase C (PKC) family of serine-threonine kinases are important regulators of immune cell survival. Ingenol 3-angelate (PEP005) activates a broad range of PKC isoforms and induces apoptosis in acute myeloid leukemia cells by activating the PKC isoform PKCδ. We show here that, in contrast to its effect on leukemic cells, PEP005 provides a strong survival signal to resting and activated human T cells. The antiapoptotic effect depends upon the activation of PKCθ. This PKC isoform is expressed in T cells but is absent in myeloid cells. Further studies of the mechanism involved in this process showed that PEP005 inhibited activated CD8+ T cell apoptosis through the activation of NFκB downstream of PKCθ, leading to increased expression of the antiapoptotic proteins Mcl-1 and Bcl-xL. Transfection of CD8+ T cells with dominant-negative PKCθ diminished the prosurvival effect of PEP005 significantly. Ectopic expression of PKCθ in the acute myeloid leukemia cell line NB4 turned their response to PEP005 from an increased to decreased rate of apoptosis. Therefore, in contrast to myeloid leukemia cells, PEP005 provides a strong survival signal to T cells, and the expression of functional PKCθ influences whether PKC activation leads to an anti- or proapoptotic outcome in the cell types tested. 相似文献
997.
Marcel Gubler Sung Min Park Mike Jetten Gregory Stephanopoulos Anthony J. Sinskey 《Applied microbiology and biotechnology》1994,40(6):857-863
The phosphoenol pyruvate carboxylase gene (ppc) of lysine-producing Corynebacterium glutamicum and C. lactofermentum strains was inactivated by marker exchange mutagenesis. The mutants lacked completely phosphoenol pyruvate carboxylase (PEP carboxylase) activity, but grew in minimal medium containing glucose as the sole carbon source. In addition, the ppc
– strains produced equivalent titers of lysine in shake flasks and in 10-l fermentation experiments as their parent strains. To address the question of how ppc
–
Corynebacterium strains generate oxaloacetate (OAA) for their own metabolism as well as for high-level lysine production, we measured the activities of enzymes leading to OAA synthesis. Whereas pyruvate carboxylase activity was not detected in any of the strains, phosphoenol pyruvate carboxykinase (PEP carboxykinase) activity was found to be significantly higher in C. glutamicum ppc mutants compared to the parent strains. On the other hand, PEP carboxykinase activity in C. lactofermentum was essentially absent. As glyxylate cycle enzymes are strongly repressed by glucose, they are not likely to compensate for the lack of PEP carboxylase activity. PEP carboxykinase, among several candidates, could play this role.
Correspondence to: M. Gubler 相似文献
998.
Annika Vaksmaa Simon Guerrero-Cruz Theo A. van Alen Geert Cremers Katharina F. Ettwig Claudia Lke Mike S. M. Jetten 《Applied microbiology and biotechnology》2017,101(18):7075-7084
Paddy fields are a significant source of methane and contribute up to 20% of total methane emissions from wetland ecosystems. These inundated, anoxic soils featuring abundant nitrogen compounds and methane are an ideal niche for nitrate-dependent anaerobic methanotrophs. After 2 years of enrichment with a continuous supply of methane and nitrate as the sole electron donor and acceptor, a stable enrichment dominated by ‘Candidatus Methanoperedens nitroreducens’ archaea and ‘Candidatus Methylomirabilis oxyfera’ NC10 phylum bacteria was achieved. In this community, the methanotrophic archaea supplied the NC10 phylum bacteria with the necessary nitrite through nitrate reduction coupled to methane oxidation. The results of qPCR quantification of 16S ribosomal RNA (rRNA) gene copies, analysis of metagenomic 16S rRNA reads, and fluorescence in situ hybridization (FISH) correlated well and showed that after 2 years, ‘Candidatus Methanoperedens nitroreducens’ had the highest abundance of (2.2 ± 0.4 × 108) 16S rRNA copies per milliliter and constituted approximately 22% of the total microbial community. Phylogenetic analysis showed that the 16S rRNA genes of the dominant microorganisms clustered with previously described ‘Candidatus Methanoperedens nitroreducens ANME2D’ (96% identity) and ‘Candidatus Methylomirabilis oxyfera’ (99% identity) strains. The pooled metagenomic sequences resulted in a high-quality draft genome assembly of ‘Candidatus Methanoperedens nitroreducens Vercelli’ that contained all key functional genes for the reverse methanogenesis pathway and nitrate reduction. The diagnostic mcrA gene was 96% similar to ‘Candidatus Methanoperedens nitroreducens ANME2D’ (WP_048089615.1) at the protein level. The ‘Candidatus Methylomirabilis oxyfera’ draft genome contained the marker genes pmoCAB, mdh, and nirS and putative NO dismutase genes. Whole-reactor anaerobic activity measurements with methane and nitrate revealed an average methane oxidation rate of 0.012 mmol/h/L, with cell-specific methane oxidation rates up to 0.57 fmol/cell/day for ‘Candidatus Methanoperedens nitroreducens’. In summary, this study describes the first enrichment and draft genome of methanotrophic archaea from paddy field soil, where these organisms can contribute significantly to the mitigation of methane emissions. 相似文献
999.
Perlson E Hanz S Medzihradszky KF Burlingame AL Fainzilber M 《Journal of neurobiology》2004,58(2):287-294
The cell body of a lesioned neuron must receive accurate and timely information on the site and extent of axonal damage, in order to mount an appropriate response. Specific mechanisms must therefore exist to transmit such information along the length of the axon from the lesion site to the cell body. Three distinct types of signals have been postulated to underlie this process, starting with injury-induced discharge of axon potentials, and continuing with two distinct types of retrogradely transported macromolecular signals. The latter include, on the one hand, an interruption of the normal supply of retrogradely transported trophic factors from the target; and on the other hand activated proteins emanating from the injury site. These activated proteins are termed "positive injury signals", and are thought to be endogenous axoplasmic proteins that undergo post-translational modifications at the lesion site upon axotomy, which then target them to the retrograde transport system for trafficking to the cell body. Here, we summarize the work to date supporting the positive retrograde injury signal hypothesis, and provide some new and emerging proteomic data on the system. We propose that the retrograde positive injury signals form part of a complex that is assembled by a combination of different processes, including post-translational modifications such as phosphorylation, regulated and transient proteolysis, and local axonal protein synthesis. 相似文献
1000.
Lugg H Sammons RL Marquis PM Hewitt CJ Yong P Paterson-Beedle M Redwood MD Stamboulis A Kashani M Jenkins M Macaskie LE 《Biotechnology letters》2008,30(3):481-491
A strain of Serratia sp. showed intracellular electron-transparent inclusion bodies when incubated in the presence of citrate and glycerol 2-phosphate
without nitrogen source following pre-growth under carbon-limitation in continuous culture. About 1.3 mmol citrate were consumed
per 450 mg biomass, giving a calculated yield of maximally 55% of stored material per g of biomass dry wt. The inclusion bodies
were stained with Sudan Black and Nile Red (NR), suggesting a lipid material, which was confirmed as polyhydroxybutyrate (PHB)
by analysis of molecular fragments by GC and by FTIR spectroscopy of isolated bio-PHB in comparison with reference material.
Multi-parameter flow cytometry in conjunction with NR fluorescence, and electron microscopy, showed that not all cells contained
heavy PHB bodies, suggesting the potential for increasing the overall yield. The economic attractiveness is enhanced by the
co-production of nanoscale hydroxyapatite (HA), a possible high-value precursor for bone replacement materials. 相似文献