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951.
Hua Lin Christelle Doebelin Rémi Patouret Ruben D. Garcia-Ordonez Venkatasubramanian Dharmarajan Claudia Ruiz Bayona Michael D. Cameron Patrick R. Griffin Theodore M. Kamenecka 《Bioorganic & medicinal chemistry letters》2018,28(8):1313-1319
Herein we report the design and synthesis of a series of simple phenol amide ERRγ agonists based on a hydrazone lead molecule. Our structure activity relationship studies in this series revealed the phenol portion of the molecule to be required for activity. Attempts to replace the hydrazone with more suitable chemotypes led to a simple amide as a viable alternative. Differential hydrogen-deuterium exchange experiments were used to help understand the structural basis for binding to ERRγ and aid in the development of more potent ligands. 相似文献
952.
Griffin Kevin L. Bashkin Michael A. Thomas Richard B. Strain Boyd R. 《Plant and Soil》1997,190(1):11-18
We measured CO2 efflux from intact root/rhizosphere systems of 155 day old loblolly (Pinus taeda L.) and ponderosa (Pinus ponderosa Dougl. ex Laws.) pine seedlings in order to study the effects of elevated atmospheric CO2 on the below-ground carbon balance of coniferous tree seedlings. Seedlings were grown in sterilized sand culture, watered daily with either 1, 3.5 or 7 mt M NH
4
+
, and maintained in an atmosphere of either 35 or 70 Pa CO2. Carbon dioxide efflux (mol CO2 plant–1 s–1) from the root/rhizosphere system of both species significantly increased when seedlings were grown in elevated CO2, primarily due to large increases in root mass. Specific CO2 efflux (mol CO2 g root–1 s–1) responded to CO2 only under conditions of adequate soil nitrogen availability (3.5 mt M). Under these conditions, CO2 efflux rates from loblolly pine increased 70% from 0.0089 to 0.0151 mol g–1 s–1 with elevated CO2 while ponderosa pine responded with a 59% decrease, from 0.0187 to 0.0077 mol g–1 s–1. Although below ground CO2 efflux from seedlings grown in either sub-optimal (1 mt M) or supra-optimal (7 mt M) nitrogen availability did not respond to CO2, there was a significant nitrogen treatment effect. Seedlings grown in supra-optimal soil nitrogen had significantly increased specific CO2 efflux rates, and significantly lower total biomass compared to either of the other two nitrogen treatments. These results indicate that carbon losses from the root/rhizosphere systems are responsive to environmental resource availability, that the magnitude and direction of these responses are species dependent, and may lead to significantly different effects on whole plant carbon balance of these two forest tree species. 相似文献
953.
D. Henry L. L. Lim L. A. Garcia Rodriguez S. Perez Gutthann J. L. Carson M. Griffin R. Savage R. Logan Y. Moride C. Hawkey S. Hill J. T. Fries 《BMJ (Clinical research ed.)》1996,312(7046):1563-1566
OBJECTIVE--To compare the relative risks of serious gastrointestinal complications reported with individual non-steroidal anti-inflammatory drugs. DESIGN--Systematic review of controlled epidemiological studies that found a relation between use of the drugs and admission to hospital for haemorrhage or perforation. SETTING--Hospital and community based case-control and cohort studies. MAIN OUTCOME MEASURES--(a) Estimated relative risks of gastrointestinal complications with use of individual drugs, exposure to ibuprofen being used as reference; (b) a ranking that best summarised the sequence of relative risks observed in the studies. RESULTS--12 studies met the inclusion criteria. 11 provided comparative data on ibuprofen and other drugs. Ibuprofen ranked lowest or equal lowest for risk in 10 of the 11 studies. Pooled relative risks calculated with exposure to ibuprofen used as reference were all significantly greater than 1.0 (interval of point estimates 1.6 to 9.2). Overall, ibuprofen was associated with the lowest relative risk, followed by diclofenac. Azapropazone, tolmetin, ketoprofen, and piroxicam ranked highest for risk and indomethacin, naproxen, sulindac, and aspirin occupied intermediate positions. Higher doses of ibuprofen were associated with relative risks similar to those with naproxen and indomethacin. CONCLUSIONS--The low risk of serious gastrointestinal complications with ibuprofen seems to be attributable mainly to the low doses of the drug used in clinical practice. In higher doses ibuprofen is associated with a similar risk to other non-steroidal anti-inflammatory drugs. Use of low risk drugs in low dosage as first line treatment would substantially reduce the morbidity and mortality due to serious gastrointestinal toxicity from these drugs. 相似文献
954.
William L Duax Jane F Griffin Debashis Ghosh 《Current opinion in structural biology》1996,6(6):813-823
Enzymes that modulate the level of circulating steroid hormone can be used to combat steroid-dependent disorders. Members of the NADPH-dependent short chain dehydrogenase/reductase (SDR) family control blood pressure, fertility, and natural and neoplastic growth. Despite the fact that only one amino acid residue is strictly conserved in the 60 known members of the family, all appear to have the dinucleotide-binding Rossmann fold and homologous catalytic residues containing the conserved tyrosine. Variation in the amino acid composition of the substrate binding pocket creates specificity of binding for steroids, prostaglandins, sugars and alcohols. Licorice induces high blood pressure by inhibiting an SDR in the kidney, and appears to combat ulcers by inhibiting another in the stomach. Detailed X-ray analyses of various members of the family should allow the design of potent, tissue-specific, highly selective inhibitors. 相似文献
955.
Utility of alkaline protease from marine shipworm bacterium in industrial cleansing applications 总被引:2,自引:0,他引:2
Summary An alkaline protease, previously isolated from a symbiotic bacterium found in the gland of Deshayes of marine shipworm, was evaluated as a cleansing additive. The protease nearly doubled the cleaning power of a standard phosphate detergent at temperatures up to 50°C as determined by fabric swatch assays. The enzyme was, however, ineffective at 70°C. In both fresh and seawater, it was also an efficient presoak. The cleaning power of a non-phosphate detergent was significantly improved by added protease, independent of the pH range 10 to 12. The enzyme degraded lysozyme, the major protein contaminant of contact lenses, more extensively than subtilisin and was effective in solutions containing hydrogen peroxide, often employed to sterilize lenses. The protease was unusually stable in sodium perborate, as well as hydrogen peroxide, and retained good activity in the presence of sodium hypochloride. 相似文献
956.
Development of a PCR protocol for sensitive detection of Cryptosporidium oocysts in water samples. 总被引:18,自引:4,他引:14
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D W Johnson N J Pieniazek D W Griffin L Misener J B Rose 《Applied microbiology》1995,61(11):3849-3855
The development of a reliable method of using PCR for detection of Cryptosporidium oocysts in environmental samples with oligonucleotide primers which amplify a portion of the sequence encoding the small (18S) subunit of rRNA producing a 435-bp product was demonstrated. The PCR assay was found to provide highly genus-specific detection of Cryptosporidium spp. after release of nucleic acids from oocysts by a simple freeze-thaw procedure. The assay routinely detected 1 to 10 oocysts in purified oocyst preparations, as shown by direct microscopic counts and by an immunofluorescence assay. The sensitivity of the PCR assay in some seeded environmental water samples was up to 1,000-fold lower. However, this interference was eliminated by either flow cytometry or magnetic-antibody capture. Sensitivity was also improved 10- to 1,000-fold by probing of the PCR product on dot blots with an oligonucleotide probe detected by chemiluminescence. Confirmation of the presence of Cryptosporidium oocysts in water samples from the outbreak in Milwaukee, Wis., was obtained with this technique, and PCR was found to be as sensitive as immunofluorescence for detection of oocysts in wastewater concentrates. 相似文献
957.
Abutilon theophrasti (C3) and Amaranthus retroflexus (C4), were grown from seed at four partial pressures of CO2: 15 Pa (below Pleistocene minimum), 27 Pa (pre-industrial), 35 Pa (current), and 70 Pa (future) in the Duke Phytotron under high light, high nutrient, and wellwatered conditions to evaluate their photosynthetic response to historic and future levels of CO2. Net photosynthesis at growth CO2 partial pressures increased with increasing CO2 for C3 plants, but not C4 plants. Net photosynthesis of Abutilon at 15 Pa CO2 was 70% less than that of plants grown at 35 Pa CO2, due to greater stomatal and biochemical limitations at 15 Pa CO2. Relative stomatal limitation (RSL) of Abutilon at 15 Pa CO2 was nearly 3 times greater than at 35 Pa CO2. A photosynthesis model was used to estimate ribulose-1,5-bisphosphate carboxylase (rubisco) activity (Vcmax), electron transport mediated RuBP regeneration capacity (J
max), and phosphate regeneration capacity (PiRC) in Abutilon from net photosynthesis versus intercellular CO2 (A–C
i) curves. All three component processes decreased by approximately 25% in Abutilon grown at 15 Pa compared with 35 Pa CO2. Abutilon grown at 15 Pa CO2 had significant reductions in total rubisco activity (25%), rubisco content (30%), activation state (29%), chlorophyll content (39%), N content (32%), and starch content (68%) compared with plants grown at 35 Pa CO2. Greater allocation to rubisco relative to light reaction components and concomitant decreases in J
max and PiRC suggest co-regulation of biochemical processes occurred in Abutilon grown at 15 Pa CO2. There were no significant differences in photosynthesis or leaf properties in Abutilon grown at 27 Pa CO2 compared with 35 Pa CO2, suggesting that the rise in CO2 since the beginning of the industrial age has had little effect on the photosynthetic performance of Abutilon. For Amaranthus, limitations of photosynthesis were balanced between stomatal and biochemical factors such that net photosynthesis was similar in all CO2 treatments. Differences in photosynthetic response to growth over a wide range of CO2 partial pressures suggest changes in the relative performance of C3 and C4 annuals as atmospheric CO2 has fluctuated over geologic time. 相似文献
958.
Direct and Indirect Effects of Atmospheric Carbon Dioxide Enrichment on Leaf Respiration of Glycine max (L.) Merr 总被引:11,自引:2,他引:9
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![点击此处可从《Plant physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Long-term and short-term effects of CO2 enrichment on dark respiration were investigated using soybean (Glycine max [L.] Merr.) plants grown at either 35.5 or 71.0 Pa CO2. Indirect effects, or effects of growth in elevated CO2, were examined using a functional model that partitioned respiration into growth and maintenance components. Direct effects, or immediate effects of a short-term change in CO2, were examined by measuring dark respiration, first, at the CO2 partial pressure at which plants were grown, and second, after equilibration in the reciprocal CO2 partial pressure. The functional component model indicated that the maintenance coefficient of respiration increased 34% with elevated CO2, whereas the growth coefficient was not significantly affected. Changes in maintenance respiration were correlated with a 33% increase in leaf total nonstructural carbohydrate concentration, but leaf nitrogen content of soybean leaves was not affected by CO2 enrichment. Thus, increased maintenance respiration may be a consequence of increased nonstructural carbohydrate accumulation. When whole soybean plants were switched from low CO2 to high CO2 for a brief period, leaf respiration was always reduced. However, this direct effect of CO2 partial pressure was approximately 50% less in plants grown in elevated CO2. We conclude from this study that there are potentially important effects of CO2 enrichment on plant respiration but that the effects are different for plants given a short-term increase in CO2 partial pressure versus plants grown in elevated CO2. 相似文献
959.
P. J. Canfield N. Quartararo D. L. Griffin G. N. Tsoukalas S. E. Cocaro 《Journal of fish biology》1994,44(5):849-856
Reference values for common haematological and biochemical tests were established for 64 captive Australian snapper, Pagrus auratus (Bloch & Schneider). Fish were bled from caudal vertebral sinuses after benzocaine anaesthesia. Haematological results were extremely variable for total leucocytes and types of leucocytes. There was no correlation between leucocyte counts and teucocrit values (R2 =0·37). Thrombocytes were not determined by direct cell counting due to problem of aggregation. Polychromasia was common but did not correlate with reticulocyte counts (R2 =0·08). Biochemical results were extremely variable for creatine kinase and aspartate transaminase but this was considered a direct result of muscle damage during collection. 相似文献