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91.
Richard Caldwell Lesley Liu-Bujalski Hui Qiu Igor Mochalkin Reinaldo Jones Constantin Neagu Andreas Goutopoulos Roland Grenningloh Theresa Johnson Brian Sherer Anna Gardberg Ariele Viacava Follis Federica Morandi Jared Head 《Bioorganic & medicinal chemistry letters》2018,28(21):3419-3424
Btk is an attractive target for the treatment of a range of Bcell malignancies as well as several autoimmune diseases such as murine lupus and rheumatoid arthritis. Several covalent irreversible inhibitors of Btk are currently in development including ibrutinib which was approved for treatment of B-cell malignancies. Herein, we describe our efforts using X-ray guided structure based design (SBD) to identify a novel chemical series of covalent Btk inhibitors. The resulting pyridine carboxamides were potent and selective inhibitors of Btk having excellent enzymatic and cellular inhibitory activity. 相似文献
92.
Maryory M. Turcios Margarita M. A. Jaramillo José F. do Vale Jr Philip M. Fearnside Reinaldo Imbrozio Barbosa 《Global Change Biology》2016,22(1):190-197
Forest fires (paleo + modern) have caused charcoal particles to accumulate in the soil vertical profile in Amazonia. This forest compartment is a long‐term carbon reservoir with an important role in global carbon balance. Estimates of stocks remain uncertain in forests that have not been altered by deforestation but that have been impacted by understory fires and selective logging. We estimated the stock of pyrogenic carbon derived from charcoal accumulated in the soil profile of seasonal forest fragments impacted by fire and selective logging in the northern portion of Brazilian Amazonia. Sixty‐nine soil cores to 1‐m depth were collected in 12 forest fragments of different sizes. Charcoal stocks averaged 3.45 ± 2.17 Mg ha?1 (2.24 ± 1.41 Mg C ha?1). Pyrogenic carbon was not directly related to the size of the forest fragments. This carbon is equivalent to 1.40% (0.25% to 4.04%) of the carbon stocked in aboveground live tree biomass in these fragments. The vertical distribution of pyrogenic carbon indicates an exponential model, where the 0–30 cm depth range has 60% of the total stored. The total area of Brazil's Amazonian seasonal forests and ecotones not altered by deforestation implies 65–286 Tg of pyrogenic carbon accumulated along the soil vertical profile. This is 1.2–2.3 times the total amount of residual pyrogenic carbon formed by biomass burning worldwide in 1 year. Our analysis suggests that the accumulated charcoal in the soil vertical profile in Amazonian forests is a substantial pyrogenic carbon pool that needs to be considered in global carbon models. 相似文献
93.
O C Briones L Hanna E Jawetz C R Dawson H B Ostler 《Journal of immunology (Baltimore, Md. : 1950)》1974,113(4):1262-1270
94.
Survival of Listeria monocytogenes in raw milk treated in a pilot plant size pasteurizer 总被引:6,自引:0,他引:6
J F Fernandez Garayzabal L Dominguez Rodriguez J A Vazquez Boland E F Rodriguez Ferri V Briones Dieste J L Blanco Cancelo G Suarez Fernandez 《The Journal of applied bacteriology》1987,63(6):533-537
The survival of Listeria monocytogenes in raw milk treated in a pilot plant size pasteurizer was investigated. Raw milk was inoculated with different initial concentrations of L. monocytogenes and heated at temperatures ranging from 69 degrees to 73 degrees C. Listerias were not isolated from any of the milk samples immediately after thermal treatment. They were isolated, however, from 46.6% of heated samples (none from samples heated at 73 degrees C) after variable periods at refrigeration temperature. The results suggest that a low number of listerias survive some thermal treatments, but a cold enrichment is necessary to repair the thermally injured cells and detect these organisms in milk. The importance of the isolation technique in the recovery of listerias from pasteurized milk samples is discussed. 相似文献
95.
Latency in human infections with TRIC agents 总被引:15,自引:0,他引:15
96.
ADENOSINE TRIPHOSPHATASE ACTIVITY IN THE MEMBRANES OF THE SQUID NERVE FIBER 总被引:5,自引:4,他引:1 下载免费PDF全文
María Teresa Sabatini Reinaldo Dipolo Raimundo Villegas 《The Journal of cell biology》1968,38(1):176-183
This investigation deals with the localization of sites of ATPase activity, especially of transport ATPase, in nerve fibers of the squid Doryteuthis plei, at the subcellular level. Splitting of ATP liberates inorganic phosphate which reacts with lead to form a precipitate in the tissue. The reaction was made on nerve fibers fixed with glutaraldehyde. Frozen slices were incubated in Wachstein-Meisel medium containing ATP and Pb(NO3)2. Deposits of reaction product were found in the axolemma (towards its axoplasmic side), Schwann cell membranes (mainly at the channels crossing the layer), and mitochondria. Control experiments revealed that no deposits were observed in nerve fibers fixed in osmium tetroxide prior to incubation in the medium containing ATP, or in nerve fibers incubated without substrate or with adenosine monophosphate, adenosine diphosphate, glycerophosphate, or guanosine triphosphate as substrate. For evaluation of transport ATPase activity, these findings were compared with results obtained with nerve fibers treated with G-strophanthin or K-strophanthoside before or after glutaraldehyde fixation. The cardiac glycosides produced a disappearance or diminution of the deposits. The largest inhibitory effect was observed in the axolemma. The findings indicate that the highest ATPase activity is localized in the axolemma and may be due primarily to transport ATPase. 相似文献
97.
Role of potassium tellurite and brain heart infusion in expression of the hemolytic phenotype of Listeria spp. on agar plates. 下载免费PDF全文
J F Fernandez-Garayzabal C Delgado M Blanco J A Vazquez-Boland V Briones G Suarez L Dominguez 《Applied microbiology》1992,58(1):434-438
The influence of potassium tellurite (PT) and brain heart infusion agar (Difco), two components of modified Listeria selective agar medium (LSAMm), on the hemolytic phenotype of Listeria spp. was studied. L. monocytogenes and L. ivanovii displayed bigger zones of hemolysis on brain heart intusion agar compared with on Columbia agar base. The addition of PT increased the sizes of zones of hemolysis displayed by L. monocytogenes. This effect seemed to be produced by the enhancement of the cytolytic effect of listeriolysin O. PT decreased the hemolysis produced by L. ivanovii, and this effect seemed to be due to an inhibition of the sphingomyelinase C produced by this species. 相似文献
98.
A. Valiente-Banuet A. Bolongaro-Crevenna O. Briones E. Ezcurra M. Rosas H. Nunez G. Barnard E. Vazquez 《植被学杂志》1991,2(1):15-20
Abstract. The Zapotitlán de las Salinas valley, central Mexico, harbours a high diversity of cacti. Pattern analysis indicated that the establishment of two columnar cacti, Neobuxbaumia tetetzo and Cephalocereus hoppenstedtii, and of three small globose cacti, Coryphantapallida, Mammillaria colina andM casoi, is aggregated and associated with perennial nurse shrubs. Some nurse species, Castela tortuosa, Caesalpinia melanadenia and Eupatorium spinosarum have a higher number of cacti beneath their canopies than would be expected by chance. A replacement pattern was found between the columnar cacti and their nurses, an aspect which was not found with the globose cacti. Following the assumption that protection against excessive radiation is the main factor determining the nurse effect, the azimuth orientation of the cacti with respect to their nurses was evaluated. Only Coryphanta pallida presented a non-random distribution with a tendency towards the North and West. The difference in maximum temperature between the soil surface under the different nurse species and of open spaces, which is reached at midday, was 16 °C. No significant differences were found in beneath-canopy temperatures for the three nurse species considered. Soil nitrogen levels were significantly lower beneath the different nurse plants than in open spaces. This result suggests that soil fertility is not an important factor in the nurse-plant phenomenon in Zapotitlán. 相似文献
99.
100.
A membrane fraction enriched in axolemma was obtained from optic nerves of the squid (Sepiotheutis sepioidea) by differential centrifugation and density gradient fractionation. The preparation showed an oligomycin- and NaN3-insensitive (Ca2+ + Mg2+)-ATPase activity. The dependence of the ATPase activity on calcium concentration revealed the presence of two saturable components. One had a high affinity for calcium () and the second had a comparatively low affinity (). Only the high-affinity component was specifically inhibited by vanadate (K1 = 35 μM). Calmodulin (12.5 μ/ml) stimulated the (Ca2+ + Mg2+)-ATPase by approx. 50%, and this stimulation was abolished by trifluoperazine (10 μM). Further treatment of the membrane fraction with 1% Nonidet P-40 resulted in a partial purification of the ATPase about 15-fold compared to the initial homogenate. This (Ca2+ + Mg2+)-ATPase from squid optic nerve displays some properties similar to those of the uncoupled Ca2+-pump described in internally dialyzed squid axons, suggesting that it could be its enzymatic basis. 相似文献