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101.
B. Gopal Reddy Dr. Jonathan D. Silk Dr. Mariolina Salio Dr. Rengarajan Balamurugan Dr. Dawn Shepherd Gerd Ritter Dr. Vincenzo Cerundolo Prof. Dr. Richard R. Schmidt Prof. Dr. 《ChemMedChem》2009,4(2):171-175
Based on the crystal structures of human α‐GalCer–CD1d and iNKT–α‐GalCer–CD1d complexes, nonglycosidic analogues of α‐GalCer were synthesized. They activate iNKT cells resulting in dendritic cell maturation and the priming of antigen‐specific T and B cells. Therefore, they are attractive adjuvants in vaccination strategies for cancer and infectious diseases.
102.
Axial concentration profiles of O2, CO2 and SO2 have been measured at different radial positions in a coal-fired fluidized bed combustor. The profiles show some spatial inhomogeneity in the bed, the degree of which depends on fluidizing velocity and amount of excess air. Comparison of SO2- with CO2-concentration profiles reveals that SO2 is formed in proportion to CO2 only with anthracite as fuel. With bituminous coals, SO2 is preferentially formed near the coal feed point. These results are discussed with regard to characteristic times of mixing and chemical reaction in fluidized beds, and SO2-formation characteristics of the employed coals obtained in a thermobalance. 相似文献
103.
Burning profiles and SO2-formation profiles were measured simultaneously for four different coals by slowly heating coal samples in a flow of air in a thermobalance. The profiles of weight loss and SO2 formation have the same shape with anthracite combustion. The SO2-formation profiles of bituminous coals usually display two peaks that approximately correspond to the release of volatile matter and combustion of char in the burning profiles. No correlations could be found between either the types of sulphur present in the raw coals or the ratio of volatile matter to fixed carbon and the shape of the SO2-formation profiles for the bituminous coals. 相似文献
104.
Zhiying Zhang Elaine Lanza Penny M. Kris-Etherton Nancy H. Colburn Deborah Bagshaw Michael J. Rovine Jan S. Ulbrecht Gerd Bobe Robert S. Chapkin Terryl J. Hartman 《Lipids》2010,45(9):765-775
Clinical studies have shown that fiber consumption facilitates weight loss and improves lipid profiles; however, the beneficial
effects of high fermentable fiber low glycemic index (GI) diets under conditions of weight maintenance are unclear. In the
Legume Inflammation Feeding Experiment, a randomized controlled cross-over feeding study, 64 middle-aged men who had undergone
colonoscopies within the previous 2 years received both a healthy American (HA) diet (no legume consumption, fiber consumption = 9 g/1,000 kcal,
and GI = 69) and a legume enriched (1.5 servings/1,000 kcal), high fiber (21 g/1,000 kcal), low GI (GI = 38) diet (LG) in
random order. Diets were isocaloric and controlled for macronutrients including saturated fat; they were consumed each for
4 weeks with a 2–4 week break separating dietary treatments. Compared to the HA diet, the LG diet led to greater declines
in both fasting serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) (P < 0.001 and P < 0.01, respectively). Insulin-resistant (IR) subjects had greater reductions in high density lipoprotein cholesterol (HDL-C;
P < 0.01), and triglycerides (TAG)/HDL-C (P = 0.02) after the LG diet, compared to the HA diet. Insulin-sensitive (IS) subjects had greater reductions in TC (P < 0.001), LDL-C (P < 0.01), TC/HDL-C (P < 0.01), and LDL-C/HDL-C (P = 0.02) after the LG diet, compared to the HA diet. In conclusion, a high legume, high fiber, low GI diet improves serum
lipid profiles in men, compared to a healthy American diet. However, IR individuals do not achieve the full benefits of the
same diet on cardiovascular disease (CVD) lipid risk factors. 相似文献
105.
Jessica L. Braun Mia S. Geromella Sophie I. Hamstra Holt N. Messner Val A. Fajardo 《International journal of molecular sciences》2021,22(21)
It is well established that microgravity exposure causes significant muscle weakness and atrophy via muscle unloading. On Earth, muscle unloading leads to a disproportionate loss in muscle force and size with the loss in muscle force occurring at a faster rate. Although the exact mechanisms are unknown, a role for Ca2+ dysregulation has been suggested. The sarco(endo)plasmic reticulum Ca2+ ATPase (SERCA) pump actively brings cytosolic Ca2+ into the SR, eliciting muscle relaxation and maintaining low intracellular Ca2+ ([Ca2+]i). SERCA dysfunction contributes to elevations in [Ca2+]i, leading to cellular damage, and may contribute to the muscle weakness and atrophy observed with spaceflight. Here, we investigated SERCA function, SERCA regulatory protein content, and reactive oxygen/nitrogen species (RONS) protein adduction in murine skeletal muscle after 35–37 days of spaceflight. In male and female soleus muscles, spaceflight led to drastic impairments in Ca2+ uptake despite significant increases in SERCA1a protein content. We attribute this impairment to an increase in RONS production and elevated total protein tyrosine (T) nitration and cysteine (S) nitrosylation. Contrarily, in the tibialis anterior (TA), we observed an enhancement in Ca2+ uptake, which we attribute to a shift towards a faster muscle fiber type (i.e., increased myosin heavy chain IIb and SERCA1a) without elevated total protein T-nitration and S-nitrosylation. Thus, spaceflight affects SERCA function differently between the soleus and TA. 相似文献
106.
Eduardo J. M. Nascimento Brooke Norwood Allan Parker Ralph Braun Eloi Kpamegan Hansi J. Dean 《International journal of molecular sciences》2021,22(21)
Antibodies capable of activating the complement system (CS) when bound with antigen are referred to as “complement-fixing antibodies” and are involved in protection against Flaviviruses. A complement-fixing antibody test has been used in the past to measure the ability of dengue virus (DENV)-specific serum antibodies to activate the CS. As originally developed, the test is time-consuming, cumbersome, and has limited sensitivity for DENV diagnosis. Here, we developed and characterized a novel multiplex anti-DENV complement-fixing assay based on the Luminex platform to quantitate serum antibodies against all four serotypes (DENV1-4) that activate the CS based on their ability to fix the complement component 1q (C1q). The assay demonstrated good reproducibility and showed equivalent performance to a DENV microneutralization assay that has been used to determine DENV serostatus. In non-human primates, antibodies produced in response to primary DENV1-4 infection induced C1q fixation on homologous and heterologous serotypes. Inter-serotype cross-reactivity was associated with homology of the envelope protein. Interestingly, the antibodies produced following vaccination against Zika virus fixed C1q on DENV. The anti-DENV complement fixing antibody assay represents an alternative approach to determine the quality of functional antibodies produced following DENV natural infection or vaccination and a biomarker for dengue serostatus, while providing insights about immunological cross-reactivity among different Flaviviruses. 相似文献
107.
Isabela C.L. Leocadio Christianne V. Miana Silvana Braun Martin Schmal 《Applied catalysis. B, Environmental》2008,84(3-4):843-849
The literature reported different studies of soot combustion reaction under very distinct experimental conditions, which can include different values of catalyst:soot weight ratios, gas flow and heating rates. Therefore, avoiding screening of innumerable catalysts or empirical experiments, this work aims to present a general methodology based on a statistical experimental design of experiments with soot combustion, evaluating different reaction conditions and parameters that can be used for any other similar study. In this way, the effect of experimental conditions on the parameters used for evaluating the performance of Mo/Al2O3, a promising system previously studied, and Pt/Al2O3, a notorious catalytic system, were studied by a complete factorial experimental design. The results have shown that the experimental conditions strongly interfere with the parameters used for evaluating the catalytic performance and then it may generate incorrect conclusions.The effects of interaction between different conditions on the activity and mainly on the selectivity of CO2 permitted to explain the performance of catalysts on soot combustion and to distinguish different pathways of catalytic and non-catalytic reactions under specific reaction conditions.The most appropriate conditions for studying soot combustion seem to be high cat:soot ratios, low heating rates and high gas flow rates, which, according to this work, must be equal to: 95:1, 2 K min−1 and 115 mL min−1, respectively. 相似文献
108.
Anna Adamczyk Yeping Xu Bernadeta Walaszek Frank Roelofs Tal Pery Karin Pelzer Karine Philippot Bruno Chaudret Hans-Heinrich Limbach Hergen Breitzke Gerd Buntkowsky 《Topics in Catalysis》2008,48(1-4):75-83
In the current study two new classes of stabile, catalytic active nanomaterials are investigated. The first class of nanoparticles consists of an inner metal core. To stabilize their structure the metal core is surrounded by organic ligands or embedded in a polymer. The second class consists of catalysts immobilized on mesoporous silica supports of SBA-3 type silica. Employing a combination of 1H, 2H, 13C and 29Si-solid state NMR spectroscopy the structure of the catalysts is analyzed. As a simple model for the catalytic properties of the particles, the activation of 2H2 gas on the surface of the particles is studied. Employing 1H and 2H gas phase NMR the kinetics of simple catalytic model reactions is studied. Employing 2H-NMR solid state NMR spectroscopy, the interaction of the metal surface with the substrate is characterized and kinetic data, which characterize the mobility of the deuterium on the surface, are extracted. For the interpretation of these data, parallel NMR studies of model η2-bound transition metal complexes are employed, which allow, owing to their simpler geometry and higher sensitivity, a quantitative modeling of the spin dynamics in the NMR experiment. 相似文献
109.
Douglas L. Schulz Robert A. Sailer Chris Braun Andrew Wagner Natalie Klaverkamp Kevin Mattson Joseph Sandstrom David Bunzow Scott Payne Jie He Jun Li Bret Chisholm 《Progress in Organic Coatings》2008
A trimethylsilane-based coating was investigated as a pretreatment for Al-2024 T3 in a novel Mg-rich primer corrosion prevention system. SiC-based thin films were deposited onto Al substrates by plasma-enhanced chemical vapor deposition (PECVD). A screening study of the pressure (P) dependence of films deposited at 350 °C showed an increase in growth rate from 0.6 to 1.9 Torr. A second screening study where P was fixed at 1.9 Torr and temperature (T) was varied from 125 to 550 °C showed decreasing growth rates with increasing temperature with an apparent transition around 300 °C. Electrochemical impedance spectroscopy (EIS) of the SiC-based films on Al-2024 after exposure to a corrosive environment (i.e., dilute Harrison solution) indicated that samples coated using SiC-based films exhibit higher low frequency impedance (i.e., 100–1000× higher) than bare Al-2024 with open circuit potential remaining 0.1 V higher for the former suggesting the SiC-based films slow the corrosion process. A Mg-rich primer was coated onto the SiC on Al-2024 with the galvanic function of the system determined by EIS. As compared to SiC on Al-2024, a similar behavior for the low frequency impedance was observed for the Mg-rich primer-coated samples with some films exhibiting 1E + 8 Ω at 0.1 Hz indicating a strong barrier property. Initial gas jet erosion using acrylic media indicates the Mg-rich primer coatings are removed in preference to the Si–C films—the first step toward demonstrating a permanent pretreatment. When successfully developed and optimized, the value of such a hard, protective coating is the reduction of a three-component coatings system (i.e., pretreatment, primer, and topcoat) to a two-component system (i.e., primer and topcoat). 相似文献
110.
Pankaj G Vashi Kristen Trukova Carolyn A Lammersfeld Donald P Braun Digant Gupta 《Nutrition journal》2010,9(1):60