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51.
The term “conjugated linoleic acid” (CLA) refers to a group of positional and geometric isomers that are derived from linoleic
acid and are found primarily in meat and milk products from ruminant animals. Due to the array of putative benefits associated
with various forms of CLA, there has been recent interest in supplementing human diets with these fatty acids especially when
weight loss is desired. However, in many animal models, CLA has been shown to decrease milk fat production. There is some
concern, therefore, that maternal CLA supplementation during lactation might inadvertently decrease nutrient supply to the
nursing infant. However, there is only limited research on the effect of CLA consumption on milk fat content in women. Based
on previously published work from our laboratory, we hypothesized that CLA supplementation would reduce the milk fat percentage
in lactating women in a dose-dependent manner. Breastfeeding women (n = 12) were assigned randomly to treatments of 4 g/day safflower oil (SFO), 2 g/day CLA plus 2 g/day SFO, or 4 g/day CLA in
a double blind, 3 × 3 Latin square design. Conjugated linoleic acid supplements contained approximately equal amounts of cis9,trans11–18:2 and trans10,cis12–18:2; the two most common isoforms of CLA. Milk was collected by complete breast expression on the last day (day 5) of
each intervention period and analyzed for macronutrient and fatty acid composition. On day 4 of each intervention period,
infant milk consumption was estimated by 24 h weighing of the infant. Washout periods were 9 days in length. We observed a
dose-dependent increase in the concentrations of cis9,trans11–18:2 and trans10,cis12–18:2 in the milk fat. However, we detected neither a change in overall macronutrient composition nor infant milk consumption.
These data do not support those obtained from animal models or our previous human work suggesting that consumption of CLA
mixtures necessarily reduces milk fat. It is possible that either (1) the interpretation of our previously published data
should be reevaluated, and/or (2) there are important intra- and inter-species differences in this regard. 相似文献
52.
Substantial research suggests that the t10,c12–18:2, but not the c9,t11–18:2, isomer of conjugated linoleic acid (CLA) reduces milk fat synthesis in lactating bovine and rodent species. Because
fat is the major energy-yielding component in human milk, we were interested in whether this is true for women as well. Thus,
the effects of c9,t11–18:2 and t10,c12–18:2 on milk fat were examined in breast-feeding women (n = 12) in a double-blind, placebo-controlled, crossover study with latin-square design. The study was divided into six periods:
baseline (3 days), three intervention periods (5 days each), and two washout periods (9 days each). During each intervention
period, women consumed 750 mg/day of a supplement containing predominantly c9,t11–18:2, t10,c12–18:2, or 18:1 (olive oil placebo). Milk was collected by complete breast expression on the final day of each period. Infant
milk consumption was estimated by 24 h weighing on the penultimate day of each intervention and washout period, and maternal
adiposity (% body fat) was determined at baseline using dual energy X-ray absorptiometry. Milk c9,t11–18:2 and t10,c12–18:2 concentrations were greater (P < 0.05) during the corresponding CLA treatment periods as compared to the placebo period, providing strong evidence of subject
compliance. Both CLA isomers were transferred into milk fat at relatively high efficiency; average transfer efficiency was
estimated to be 23.3%. Compared to the placebo treatment, milk fat content was not reduced during either CLA treatment. Data
indicate that body fatness did not modify any putative effect of isomeric CLA consumption on milk fat concentration. The evidence
from this study suggests that the sensitivity of lactating women’s mammary tissue to an anti-lipogenic effect of the t10,c12–18:2 isoform of CLA may be less than previously hypothesized. 相似文献
53.
Sanghee Lee Theresa R. Mendoza Danielle N. Burner Michelle T. Muldong Christina C. N. Wu Catalina Arreola-Villanueva Abril Zuniga Olga Greenburg William Y. Zhu Jamillah Murtadha Evodie Koutouan Naomi Pineda Hao Pham Sung-Gu Kang Hyun Tae Kim Gabriel Pineda Kathleen M. Lennon Nicholas A. Cacalano Catriona H. M. Jamieson Christopher J. Kane Anna A. Kulidjian Terry Gaasterland Christina A. M. Jamieson 《International journal of molecular sciences》2022,23(6)
54.
Bruno Ribeiro Jefersson A. R. Corredor Laura Ardila Luis F. P. Santos Michelle L. Costa Mirabel C. Rezende Edson C. Botelho 《应用聚合物科学杂志》2020,137(5):48330
Vacuum filtration technique was employed in order to prepare multiwalled carbon nanotube buckypapers (MWCNT-BP) through a well-dispersed suspension of MWCNT/H2O with the aid of Triton X-100 surfactant. The obtained BP (buckypaper) was then infiltrated with a solution of poly (ether-imide) (PEI) under vacuum conditions. The visual inspection demonstrated the importance of the centrifugation procedure before the vacuum filtration of the suspension, revealing a smooth surface of the as-prepared buckypaper. Thermogravimetric experiments (TGA) and scanning electron microscopy analyses have demonstrated the role of isopropyl alcohol in the removal of Triton X-100 from the nanotube network. SEM observations of the cross-section view of the samples revealed a porous network of the fabricated BP, and an impregnated structure of the PEI/BP composite, suggesting a good interfacial bonding between MWCNT and PEI. Moreover, significant improvements were achieved in mechanical and thermal properties of PEI matrix by the incorporation of BP, as the increase of both the storage modulus (42%) and the T g (11 °C) for the PEI/BP composite. TGA have shown a significant increase in the onset decomposition temperature of the polymer by the incorporation of the BP. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48330. 相似文献
55.
56.
Tania Michelle Roberts Hans-Michael Kaltenbach Fabian Rudolf 《Yeast (Chichester, England)》2020,37(5-6):336-347
Saccharomyces cerevisiae cells grown in a small volume of chemically defined media neither reach the desired cell density nor grow at a fast enough rate to scale down the volume and increase the sample number of classical biochemical assays, as the detection limit of the readout often requires a high number of cells as an input. To ameliorate this problem, we developed and optimised a new high cell density (HCD) medium for S. cerevisiae. Starting from a widely used synthetic medium composition, we systematically varied the concentrations of all components without the addition of other compounds. We used response surface methodology to develop and optimise the five components of the medium: glucose, yeast nitrogen base, amino acids, monosodium glutamate, and inositol. We monitored growth, cell number, and cell size to ensure that the optimisation was towards a greater density of cells rather than just towards an increase in biomass (i.e., larger cells). Cells grown in the final medium, HCD, exhibit growth more similar to the complex medium yeast extract peptone dextrose (YPD) than to the synthetic defined (SD) medium. Whereas the final cell density of HCD prior to the diauxic shift is increased compared with YPD and SD about threefold and tenfold, respectively. We found normal cell-cycle behaviour throughout the growth phases by monitoring DNA content and protein expression using fluorescent reporters. We also ensured that HCD media could be used with a variety of strains and that they allow selection for all common yeast auxotrophic markers. 相似文献
57.
Evangelos Pavlakis Michelle Neumann Thorsten Stiewe 《International journal of molecular sciences》2020,21(24)
Tumor progression to a metastatic and ultimately lethal stage relies on a tumor-supporting microenvironment that is generated by reciprocal communication between tumor and stromal host cells. The tumor–stroma crosstalk is instructed by the genetic alterations of the tumor cells—the most frequent being mutations in the gene Tumor protein p53 (TP53) that are clinically correlated with metastasis, drug resistance and poor patient survival. The crucial mediators of tumor–stroma communication are tumor-derived extracellular vesicles (EVs), in particular exosomes, which operate both locally within the primary tumor and in distant organs, at pre-metastatic niches as the future sites of metastasis. Here, we review how wild-type and mutant p53 proteins control the secretion, size, and especially the RNA and protein cargo of tumor-derived EVs. We highlight how EVs extend the cell-autonomous tumor suppressive activity of wild-type p53 into the tumor microenvironment (TME), and how mutant p53 proteins switch EVs into oncogenic messengers that reprogram tumor–host communication within the entire organism so as to promote metastatic tumor cell dissemination. 相似文献
58.
Ryan S. Hippman Ivan Pavlinov Qiwen Gao Michelle K. Mavlyanova Erica M. Gerlach Prof. Leslie N. Aldrich 《Chembiochem : a European journal of chemical biology》2020,21(21):3137-3145
A systematic, diversity-oriented synthesis approach was employed to access a natural product-inspired flavonoid library with diverse chemical features, including chemical properties, scaffold, stereochemistry, and appendages. Using Cell Painting, the effects of these diversity elements were evaluated, and multiple chemical features that predict biological performance diversity were identified. Scaffold identity appears to be the dominant predictor of performance diversity, but stereochemistry and appendages also contribute to a lesser degree. In addition, the diversity of chemical properties contributed to performance diversity, and the driving chemical property was dependent on the scaffold. These results highlight the importance of key chemical features that may inform the creation of small-molecule, performance-diverse libraries to improve the efficiency and success of high-throughput screening campaigns. 相似文献
59.
Those who have been convicted of crimes are subjected to a stigma that affects many aspects of their social lives. The “felon” label brings collateral consequences that make it difficult to obtain basic human needs, including housing. This study uses the audit method to examine the effects of race, gender, and criminal history on housing outcomes. Testers, exhibiting characteristics suggestive of race and gender and disclosing one of three offenses, placed phone calls to rental property owners across the Midwest to inquire about renting a property. We found powerful negative effects for those with a criminal record seeking apartments, regardless of whether the offense was sexual or drug-related. However, we found no differences between minority and non-minority testers. We explain these findings in the context of housing as an essential resource for formerly incarcerated individuals. 相似文献
60.
Scientometrics - Axiomatic characterisation of a bibliometric index provides insight into the properties that the index satisfies and facilitates the comparison of different indices. A geometric... 相似文献