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451.
Verena Baumann Madathumpady Abubaker Habeeb Muhammed Adam J. Blanch Priyanka Dey Jessica Rodríguez-Fernández 《Israel journal of chemistry》2016,56(4):195-213
Exerting control over the size, morphology, and complexity of metal and semiconductor nanoparticles and nanostructures is a requisite for exploring novel phenomena, and the potential applications of these nanomaterials. Bottom-up colloidal chemistry syntheses can benefit from using biomolecules as active elements to influence the formation of inorganic nanoparticles. In this review, we will discuss how three main biomolecule types, (namely DNA; amino acids, peptides, and proteins; and enzymes), can affect the growth of metal and semiconductor nanoparticles. We will present and discuss the templating and non-templating roles of those biomolecules, featuring key aspects and prospects of biomolecule-assisted metal and semiconductor nanoparticle growth. 相似文献
452.
Kyriaki Antoniadou Corinna Herz Nguyen Phan Khoi Le Verena Karolin Mittermeier-Kleßinger Nadja Frster Matthias Zander Christian Ulrichs Inga Mewis Thomas Hofmann Corinna Dawid Evelyn Lamy 《International journal of molecular sciences》2021,22(20)
Salix cortex-containing medicine is used against pain conditions, fever, headaches, and inflammation, which are partly mediated via arachidonic acid-derived prostaglandins (PGs). We used an activity-guided fractionation strategy, followed by structure elucidation experiments using LC-MS/MS, CD-spectroscopy, and 1D/2D NMR techniques, to identify the compounds relevant for the inhibition of PGE2 release from activated human peripheral blood mononuclear cells. Subsequent compound purification by means of preparative and semipreparative HPLC revealed 2′-O-acetylsalicortin (1), 3′-O-acetylsalicortin (2), 2′-O-acetylsalicin (3), 2′,6′-O-diacetylsalicortin (4), lasiandrin (5), tremulacin (6), and cinnamrutinose A (7). In contrast to 3 and 7, compounds 1, 2, 4, 5, and 6 showed inhibitory activity against PGE2 release with different potencies. Polyphenols were not relevant for the bioactivity of the Salix extract but salicylates, which degrade to, e.g., catechol, salicylic acid, salicin, and/or 1-hydroxy-6-oxo-2-cycohexenecarboxylate. Inflammation presents an important therapeutic target for pharmacological interventions; thus, the identification of relevant key drugs in Salix could provide new prospects for the improvement and standardization of existing clinical medicine. 相似文献
453.
Bertrand Matthus Anja Bonte Bernadette Sinning Zoubida Charrouf 《European Journal of Lipid Science and Technology》2019,121(12)
The aim of the present work is to identify and characterize the most important aroma active compounds of argan oil from unroasted and roasted argan almonds as well as roasted almonds obtained from goat‐digested fruits by dynamic headspace GC and GC‐olfactometry with aroma dilution analysis to classify samples from the market according to their processing. While fresh ground argan almonds are characterized by only seven aroma active compounds, in argan oil from unroasted and roasted almonds, 22 and 35 aroma active compounds are found, respectively. As a result of the roasting process, 14 aroma active compounds with dilution factors >64 are detected in the oil by GC‐olfactometry. 17 aroma active compounds show significant differences between the three different argan oil qualities. These compounds are used to differentiate the quality of argan oil from the market. Practical Application: Argan oil belongs to the high‐price oils on the market but sometimes the sensory quality of the oil contradicts the positive image that has been built up for oil by unpleasant cheese‐like and fusty sensory attributes. Although some information about the composition of the volatile compounds of cold‐pressed argan oil from unroasted and roasted kernels is available, the knowledge about compounds that are typical for the aroma of argan oil is important in order to develop analytical methods for the classification of different argan oil qualities. This reduces the work for a panel group that is often time and labor consuming and sometimes the results are not reliable. The present paper demonstrates which volatile compounds show significant differences between argan oil from unroasted and roasted argan almonds as well as roasted almonds obtained from goat‐digested fruits allowing a differentiation of these oils. 相似文献
454.
Breugelmans Seger M.; Ambadar Zara; Vaca Jesús B.; Poortinga Ype H.; Setiadi Bernadette; Widiyanto Priyo; Philippot Pierre 《Canadian Metallurgical Quarterly》2005,5(2):166
Cultural variations in the associations of 12 body sensations with 7 emotions were studied in 2 rural samples from northern Mexico (n = 61) and Java, Indonesia (n = 99), with low exposure to Western influences and in 3 university student samples from Belgium (n = 75), Indonesia (n = 85), and Mexico (n = 123). Both parametric and nonparametric analyses suggest that findings from previous studies with only student samples (K. R. Scherer & H. G. Wallbott, 1994) were generalizable to the 2 rural samples. Some notable cultural deviations from common profiles were also identified. Implications of the findings for explanations of body sensations experienced with emotions and the cross-cultural study of emotions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
455.
This is the 1st study to examine the effects of individual- and program-level characteristics on treatment attrition within a prison-based setting. The sample of 1,446 men and women were from 19 programs. Differences were found in both individual- and program-level predictors of disciplinary discharges and dropouts. Dropouts were more likely to be women and enter treatment with lower levels of motivation. Individuals who were disciplinary discharges from treatment were more likely to be young, have a history of violence, and have a diagnosis of antisocial personality. Only 1 program factor--an emphasis on disciplinary discharge for violation of program rules--was associated with disciplinary discharge. The clinical implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
456.
Deissler V Rüger R Frank W Fahr A Kaiser WA Hilger I 《Small (Weinheim an der Bergstrasse, Germany)》2008,4(8):1240-1246
This study assesses if specially designed fluorescent liposomes can be used as contrast agent for near-infrared fluorescence (NIRF) optical imaging of cultured macrophages in vitro and for NIRF imaging of inflammatory processes, like edema, in an in vivo mouse model. Fluorescent liposomes are prepared by the film hydration and extrusion method using cholesterol, L-phosphatidylcholine, and the NIR fluorescent dye DY-676-C(18) ester. Photon correlation spectroscopy and flow cytometry reveal that fluorescent liposomes are structurally stable for up to 133 days. Distinct uptake/labeling of cultured murine J774 macrophages is demonstrated by confocal laser scanning microscopy (CLSM), flow cytometry, and macroscopic NIRF imaging system at wavelengths >670 nm. Moreover, CLSM analysis reveals fluorescence signals within intracellular compartments. Ear edema is induced in mice (n = 16) by subcutaneous injection of zymosan A. Whole-body NIRF imaging is performed after intravenous injection (0-24 h) of fluorescent liposomes (55 nmol dye per kg body weight). Distinctly higher fluorescence intensities (1613.6 +/- 61.7 a.u.) are detected at inflamed areas of diseased mice as compared to controls (892.8 +/- 19.4 a.u.). Furthermore, cell isolated from ear lavage reveals the presence of labeled F4/80 positive tissue macrophages. Taken together, the results indicate both that mouse macrophages labeled with fluorescent liposomes can be detected in vitro with fluoro-optical methods and that in vivo optical imaging of inflammatory processes with fluorescent liposomes as contrast agent is feasible. Possibly, early stages of other inflammatory diseases could also be detected by the proposed diagnostic tool in the long term. 相似文献
457.
Out of the complex influences of event, narrative and listener characteristics on narrative emotions, this paper focuses on event severity, narrative perspectives, mood, and dispositions for emotion regulation and empathy. Event severity and perspective representation were systematically varied in sad autobiographical narratives to study their influence on quantity and quality of readers' emotional response. Each of three stories were manipulated to contain elaborated perspectives, only the past protagonists' perspective (dramatic narration), and very little perspectives at all (impersonal narration). We predicted that event severity influences the quantity of emotional response, while degree of perspective representation influences plausibility and whether emotional responses are sympathetic or interactional, that is, directed against the narrator. Hypotheses were confirmed except for plausibility, and perspective representation had an effect only on anger against and dislike of the narrator. In a second study, impersonal narration evoked anger at and negative evaluations of the narrator which were related to blaming the narrator for showing too little emotional involvement. The generalizability of findings across emotions and implications for sharing of emotions in everyday and clinical settings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
458.
Helene Bohnert Max Maurer Philip C. Calder Johann Pratschke Paul Thul Verena Müller 《Nutrition journal》2018,17(1):113
Background
Data on the use of lipid emulsions containing fish-oil (FO) derived n-3 polyunsaturated fatty acids (n-3 PUFAs) in addition to medium- and long-chain triglycerides (MCT/LCT) for long-term home parenteral nutrition (HPN) are limited. This study aimed to compare HPN regimens containing either MCT/LCT/FO-derived n-3 PUFAs (test group) or MCT/LCT (control group) with respect to efficacy and safety during 8?weeks of HPN using a non-inferiority trial design with change of body mass index (BMI) as primary endpoint.Methods
This prospective, randomized, double-blind study was conducted at the Charité, Berlin, Germany, from 02/2008 until 01/2014. Adult patients (n?=?42; aged 18 to 80?years) requiring HPN for at least 8?weeks were randomly assigned to the test or control group. Assessments included weight, height, physical examination (cardiovascular system, abdomen, respiratory tract, liver, spleen, kidney, urine tract, skin, mucous membrane, neurology, psyche, musculoskeletal system, lymph nodes), bio impedance analysis, calorimetry, blood samplings (haematology, biochemistry, fatty acid analysis) and quality of life questionnaire.Results
BMI increased in both groups with 8?weeks of HPN (ΔBMI(test group)?=?1.3?±?1.1?kg/m2; ΔBMI(control group)?=?0.6?±?0.9?kg/m2) demonstrating non-inferiority of the test regimen regarding nutritional efficacy. Assessment of secondary efficacy endpoints revealed that after 8?weeks of HPN with the test regimen, the proportion of n-3 PUFAs in serum, platelet and red blood cell phospholipids significantly increased, while the proportion of n-6 PUFAs decreased. The fatty acid pattern in the control group remained mostly stable. No statistically significant differences were detected between groups regarding inflammatory markers or quality of life. Laboratory parameters reflecting the safety endpoints liver function, bone metabolism, renal function, metabolic activity, lipid metabolism, coagulation and haematology were stable in both groups and no group differences were detected regarding (serious) adverse events.Conclusions
The HPN regimen prepared with MCT/LCT/FO-derived n-3 PUFAs was at least as efficient in maintaining or even improving nutritional status during HPN as the control MCT/LCT regimen. Administration of FO-derived n-3 PUFAs for 8?weeks altered the fatty acid pattern of serum, platelet and red blood cell phospholipids. Both regimens were safe and well tolerated.Trial registration
www.clinicaltrials.gov, registration number: NCT00530738.459.
The use of alginate as a coating material for packaging applications is currently limited due to its difficult processability and high moisture sensitivity. Therefore, this study addresses the crosslinking and scale‐up to a continuous application. Three different crosslinking agents were applied: CaCl2 with ethylene diamine tetraacetic acid and two low soluble salts (CaHPO4 and CaCO3). Those were incorporated by internal setting in an alginate matrix with varying Ca2+ concentration ( ) and ratio. With the addition of Ca2+, the tensile strength and elongation at break of the cast alginate films increased. This was optimal for a of 0.010–0.015 g (g alginate)?1 dependent on the crosslinking agent. The decrease in water vapor and oxygen permeability due to crosslinking was independent of the crosslinking agent. However, the optimal aiming to decrease permeability was different for the crosslinking agents: CaHPO4 showed best results at a of 0.010 g (g alginate)?1, CaCl2 at 0.012 g (g alginate)?1, and CaCO3 at 0.027 g (g alginate)?1. Upon all analyzed properties CaHPO4 was the most promising crosslinking agent for alginate. Moreover, selected alginate formulations were successfully processed in a continuous lacquering plant. The produced two‐layer systems have very low oxygen permeabilities which can be further reduced by crosslinking. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45754. 相似文献
460.
Morise A Combe N Boué C Legrand P Catheline D Delplanque B Fénart E Weill P Hermier D 《Lipids》2004,39(4):325-334
If an increased consumption of α-linolenic acid (ALA) is to be promoted in parallel with that of n−3 long-chain-rich food,
it is necessary to consider to what extent dietary ALA can be absorbed, transported, stored, and converted into long-chain
derivatives. We investigated these processes in male hamsters, over a broad range of supply as linseed oil (0.37, 3.5, 6.9,
and 14.6% energy). Linoleic acid (LA) was kept constant (8.5% energy), and the LA/ALA ratio was varied from 22.5 to 0.6. The
apparent absorption of individual FA was very high (>96%), and that of ALA remained almost maximum even at the largest supply
(99.5%). The capacity for ALA transport and storage had no limitation over the chosen range of dietary intake. Indeed, ALA
intake was significantly correlated with ALA level not only in cholesteryl esters (from 0.3 to 9.7% of total FA) but also
in plasma phospholipids and red blood cells (RBC), which makes blood components extremely reliable as biomarkers of ALA consumption.
Similarly, ALA storage in adipose tissue increased from 0.85 to 14% of total FA and was highly correlated with ALA intake.
As for bioconversion, dietary ALA failed to increase 22∶6n−3, decreased 20∶4n−6, and efficiently increased 20∶5n−3 (EPA) in
RBC and cardiomyocytes. EPA accumulation did not tend to plateau, in accordance with identical activities of Δ5- and Δ6-desaturases
in all groups. Dietary supply of ALA was therefore a very efficient means of improving the 20∶4n−6 to 20∶5n−3 balance. 相似文献